Southeast Flooding

The flood risk is high across the Southeast to wrap up February. The storm track, which has been just north of the Southeast, will shift south allowing for several wet storms to move from the Mississippi Valley towards the east and north. As the storm track moves south this upcoming week, several disturbances will move across the Southeast. Each one creating enough lift to generate rain. Periodically, stalled frontal boundaries will be located across this region, which will act to enhance rainfall–increasing the flood threat.

It is difficult to pinpoint exactly which area will see the heaviest rainfall but at this time it appears widespread 3-6″ will fall from Louisiana east through Mississippi, Alabama, Georgia and north into parts of Tennessee and Kentucky this week with isolated 5-10″ amounts (see Fig. 1). The heavy rain axis will also extend farther east in north into Virginia and the Carolinas.

Fig. 1: Rainfall forecast through next week

The soil is saturated in this region from above average precipitation during the cool season. This, paired with a lack of foliage due to the cold season, will allow for quick runoff into area streams, creeks and rivers this upcoming week. Please remain alert of your surroundings. And, as always, TURN AROUND, DON’T DROWN!

Tropical Update: Harvey and Hurricane Safety

Hurricane Harvey, now 115 miles southeast of Corpus Christi Texas, has seen the maximum sustained winds increase to 110 this morning, just shy of major hurricane status. The minimum central pressure has dropped 947 Millibars. Harvey is expected to become a major hurricane today with winds increasing further to 120 mph. As of this 11 AM EDT, the following watches and warnings are in effect.

A Hurricane Warning is in effect from Port Mansfield to Sargent Texas. Hurricane conditions will be occurring in these areas within the next 12-24 hours.

A Tropical Storm Warning is in effect from south of Port Mansfield to the Mouth of the Rio Grande River and from North of Sargent to High Island Texas

A Tropical Storm Watch is in effect for South of the mouth of the Rio Grande to Boca de Catan Mexico

A Storm Surge Warning is in effect from Port Mansfield to High Island Texas. A Storm Surge Warning means there is a danger of life-threatening inundation from rising water moving inland from the coastline in the indicated locations. This is a life-threatening situation. Persons located within these areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions. Promptly follow evacuation and other instructions from local officials.

A Storm Surge Watch is in effect from south of Port Mansfield to the Mouth of the Rio Grande. A Storm Surge watch means there is a possibility of life-threatening inundation from rising water moving inland. Persons located within these areas should take all necessary actions to protect life and property and be on the look out for rising seas.

Forecast Information

Harvey

Hurricane Harvey continues to increase in strength this morning and is now approaching major hurricane status. Harvey is expected to be a category 3 storm when he moves ashore in Texas. Sustained winds are expected to be between 120 and 130 miles per hour with higher gusts. Harvey will be bringing life-threatening storm surge, rainfall, and wind hazards to portions of the Texas coast. Preparations to protect life and property should be completed this morning, as tropical storm force winds will first arrive in the hurricane and storm surge warning areas later today.

Life-threatening storm surge flooding could reach heights of 6 to 12 feet above ground level at the coast between the north entrance of the Padre Island National Seashore and Sargent. Devastating and life-threatening flooding is expected across the middle and upper Texas coast from heavy rainfall of 15 to 25 inches, with isolated amounts as high as 35 inches, from today through next
Wednesday.

Harvey will hug the coast after he moves inland, which could help prevent the quick weakening associated with land falling hurricanes. While Harvey will still weaken, it may be a slower process and he could maintain Tropical Storm strength longer than usual. Harvey is forecast to impact this area for several days.

Hurricane Harvey Hazards

Storm Surge and Storm Tide

Storm Surge and large waves are the greatest threats to life and property along the coast. A storm surge is an abnormal rise of water generated by a storm’s winds. Many will remember the surge from Hurrican Ike is 2008. Storm Surge with Harvey is expected to be as high as 12 feet in some locations (was 20 feet in Ike). Please check your local media sources for the exact surge totals expected for your area. Surge related flooding will be dependent on the exact timing and the tide and can vary greatly over short distances. Large waves will also be a factor at the coast. Based on the tide charts, Harvey should hit as tides are moving out and close to low tide, but onshore winds are possible during several tidal cycles.

Tornadoes

Hurricanes frequently produce tornadoes, usually in the embedded thunderstorms in the rain bands now beginning to hit the Texas coast line. They can also be associated with the eye wall. Tornadoes produced by these systems are usually weak and short lived, but they can be a threat to where they hit. A Tornado watch is expected to be posted for coastal areas of Texas and Louisiana later today.

Winds

It goes without saying that winds are a major issue with Hurricanes. Sustained winds with Harvey are expected to reach up to 120 mph with gusts reaching as high as 150 mph with some locally higher gusts. Harvey is forecast to be a major Hurricane at landfall.

Rainfall

Forecasts for Harvey have indicated significant rainfall is possible, with some models showing over 30 inches of rain. This will be a very long duration event and flooding and flash flooding will bea major issue for many areas.

Hurricane Safety

Evacuations

Many areas in Texas have had evacuation orders given, for those who are evacuating, you will need to determine a safe evacuation route inland. While evacuating, you’ll want to monitor the latest information to ensure that you will be evacuating to a location that is not also under a risk. Public services in these areas will already be strained and adding many evacuees will only cause more strain for everyone. Learning the location of official shelters will be helpful both in the event that you evacuate as well as for those who do not evacuate. Areas that are not under evacuation orders should also have shelters for the residents who end up in trouble due to hurricane hazards. Tornadoes, lightning, power outages, and property damage due to falling trees can force residents from their homes, even if a mass evacuation isn’t needed. The good news is that a quick check of traffic in this region doesn’t show any, so many heeded these orders in advance.

When evacuating, put together a go-bag. Include a disaster supply kit, including a flashlight, batteries, cash, first aid supplies, medications, and copies of your critical information if you need to evacuate. Snacks and stuff to drink will also be good for longer evacuations, especially with children. While you may stop for gas, many others are also evacuating with you so its possible that many supplies will be sold out along your route. If you haven’t already, fill up your gas tank in your local area, gas supplies may also be strained along your route. Cell phones should be charged before you leave. Have one member of your family turn their phone off while travelling together. This will ensure that if one phone does run out of battery, you will have another phone to turn on and use. All family members should have all numbers for your phones and know to call multiple numbers if they can’t get a hold of you.

You should also inform someone of your plans. If you fail to arrive at your destination due to a car accident, your contact can alert the authorities. Having them know the route you planned to take is essential in locating you.

Stay tuned to local news outlets as you travel. Conditions may change and areas you were heading to that were going to be safe may not be anymore. Harvey is brining a large area of rain to Texas and the location you were heading for may end up under a flood warning when it wasn’t before. Always ensure that the safety of your location is the top priority.

Staying at home

For those of you who are not leaving home, I would first implore you to heed local evacuations if you are under them. Evacuation orders are given for a reason. If you are under those orders it is absolutely not safe where you are. While I do realize that some properties remain even in massively damaged areas, you only put yourself and those who would need to rescue you in the event of an emergency in danger by taking that gamble. It is never just your survival on the line.

If you have not been ordered to evacuate, there are several things you should plan for. First, as I mentioned above, have a plan to be able to evacuate to a local shelter if your house if one of the unfortunate locations that falls victim to one of the more local hurricane hazards. Lighting occurs frequently within a hurricane and can strike even in areas where hurricane conditions are not occurring. You should also have a plan for any pets you may have. Not all shelters accept pets so ensure the one you may go to does.

What to bring to the shelter

You will need to make sure that you have everything you need at the shelter. While the shelter will have supplies, they don’t usually carry specific medications or your specific brand of baby food. Ensure that you have a first aid kit with all the medications taken by your family. If you are running low, see if your local pharmacy can give you more. Baby food and diapers will be needed. Your baby should be prepared for a multiple day stay at the shelter. Bring things to do as well. Books, games for children, headphones and a source of music (we all know some of you still have a Walkman) will all be desired. The shelter is not exactly a fun place to be. Bring your toiletries and blankets. The shelter will have some but we all prefer our own. Flashlights and batteries are good to have in case the power goes out at the shelter as well. Also ensure you bring identification, cash and credit cards as well as copies of your essential documentation like proof of insurance.

Protecting your home

Be aware that Hurricane winds can cause trees and branches to fall, so before a hurricane trim or remove damaged trees and limbs to keep you and your property safe.
Secure loose rain gutters and downspouts and clear any clogged areas or debris to prevent water damage to your property. When it comes to repairing your rain gutters, it’s as easy as checking out sites such as https://www.aluminiumwarehouse.co.uk/, finding the right materials and replacing your damaged/old gutters. This will help protect your property, which is what you need to consider, especially after weather conditions like thunderstorms and heavy rain. This can also help keep them lighter and not fall under the weight of all the rain. Reduce property damage by retrofitting to secure and reinforce the roof, windows and doors, including the garage doors. Plywood over windows or close storm shutters if your house has them, this can protect them from wind and debris. If you are construction inclined, hurricane clips can be installed in your attic to help secure your roof to the house. You may also want to get in touch with a home improvement service similar to Mastershield Atl that may be able to provide support for homeowners who are looking for a way to protect their roof from water damage. While it is certainly too late to hire a contractor to do this for Harvey, other storms will come along and this can be done for future storms. You can also brace your garage door and doors that lead outside with planks to keep it from blowing in. You should also close all interior doors to compartmentalize the house. This way, if a window does break in one area, the remaining areas will have protection against the elements coming in. Purchasing a portable generator or installing a generator for use during power outages is also a good idea. Remember to keep generators and other alternate power/heat sources outside, at least 20 feet away from windows and doors and protected from moisture. You should never try to power the house wiring by plugging a generator into a wall outlet. If power does go out, use a flashlight. Candles are a fire hazard.

Keeping food and water safe

The most important thing when it comes to food is to buy nonperishable goods and to store water. You do not need to buy multiple gallons of water for activities like brushing your teeth. Simply refill an old milk or water bottle with tap water and use it. You can do the same thing for bath water, pre-filling your tub is also recommended. Tap water storage can be done with any container from large pots used for cooking to old bottles and even any large plastic container. Always remember to keep using the tap water until it goes out, you don’t want to needlessly use up your supply and not be able to replenish it. For any cold food you do have, turn your refrigerator and freezer to their maximum cold settings and open them as little as possible. This will help keep things cold. Try to use up any chilled foods first so that keeping things cold becomes unnecessary and have a supply of ice on hand to keep things cold longer. While you can buy ice at the store, you can also just use ice cubes. Simply dump your tray into a plastic bag and refill the trays. Dump new ice cubes as they form and keep refilling the trays. You will be able to continue this process for as long as you have power or tap water. This also creates an emergency water supply should you run out of water. Simply melt the ice. You can also use rain water if you have a safe way to get a bucket outside to collect some. You should always try to keep a lid on your water supply. This will keep dust and bugs out of it.

After the Storm

It will be tempting to go outside after the storm has passed or during the calm period in the eye. This should be avoided. The eye is only temporary and hurricane conditions can start very quickly. After the storm, there will be a lot of damage in the region. Floods could still be occurring and the water could be contaminated. You also can’t see what’s in the water. Animals and hazards in the water could be potentially dangerous to your health. The water could even be electrically charged from downed power lines.

We here at Firsthand will do our utmost to keep you up to date with the latest information. Our thoughts go out to those in the areas affected by Harvey. Stay safe everyone.

Robert Millette

Incident Meteorologist

Braintree Emergency Management Agency

Severe weather moves from the Plains towards the Mid-Atlantic

Severe weather is a risk over the next couple of days from the Plains and Gulf Coast regions into the Appalachians towards the Mid-Atlantic.  While there is a low risk for tornadoes, there are significant risks for widespread damaging winds and  large hail.

A stationary front has been the focus for strong to severe thunderstorms over the Plains in recent days bringing over 900 reports of severe hail and wind from Texas to Wisconsin.  This front is interacting with a strong, fast moving cold front that will create the lift needed for a large area of showers and thunderstorms.  Some of these storms could be intense this morning as remnants of a Mesoscale convective system died out overnight across the Plains persists.  The severe weather moves on into the Appalachians by Sunday, and on to the Mid-Atlantic up into New England for Monday.

Saturday

The cold front, along with a strengthening low pressure system, will continue to progress southeastward from Central Iowa into Central Kansas.  The air ahead of this front remains warm and unstable with plenty of moisture.

Storms are likely to begin over Iowa and northern Kansas before spreading East from Michigan down into Missouri.  These thunderstorms are expected to form into linear squall lines over time due to weak low level shear yielding outflow dominant storms.    Any storms should begin to weaken after nightfall as they move east, where lapse rates will be lower.

Sunday

Scattered thunderstorms, with a primary risk of damaging winds, are expected from the Great Lakes into Northeast Texas.  The low pressure from Saturday will move from the Great Lakes into Canada but the cold front will remain across the Ohio Valley into the Southern Plains.

From the Great Lakes down through Tennessee, early remnants from overnight storms should clear with a moisture rich warm air-mass in place to meet the weakening cold front.  The ongoing wind regime should allow for strong multi-cluster cells to form.  Hail may also fall but will only be locally severe.

Further south, storms will be more isolated from the Texoma region into Arkansas.  Lift in this region will be weaker but the cold front will be a focus point for thunderstorms due to an elevated mixed layer and moist low level conditions.  These will form a very unstable boundary layer that could see the convective available potential energy (CAPE) approach 4000 Joules per kilogram.

In Mississippi and Alabama, scattered thunderstorms will develop during the daytime heating period.  Seasonably warm and moist air will become more unstable under conditions that have very little convective inhibition.  Strong to severe cells that do form will likely have marginally severe hail and localized damaging winds.

All southern storms should begin to weaken during the evening hours as daytime heating fades.

Starting off the work week, the Northeast and Mid-Atlantic are looking at pending severe weather as the cold front pushes east into more warm moist air Monday afternoon into the overnight hours effecting all the major metropolitan areas.

Rob

 

 

Significant storms impact both coasts

Active Pattern leads to a significant storms early next week:

Significant Storms are set to take place in an active pattern across the United States will bring severe weather to the Gulf Coast and Widespread rain with heavy mountain snow to the West.  These frequent West Coast fronts will eventually lead to a strong system developing in the south and moving off the coast of the Northeast.

Significant Storms

Showers and thunderstorms are expected to be widespread tonight in association with an upper level disturbance from portions of the Gulf Coast and Southeast to the Ohio valley and portions of the Great Lakes.   An evolving cluster of thunderstorms bring the risk for potentially damaging wind gusts, and perhaps a tornado or two, across southeastern Alabama and portions of the western Florida Panhandle by late this evening.  An increasingly organized convective system is forecast across the region and extends the Severe risk into West Central and Southwestern Georgia overnight, but this system will continue to be just disorganized enough to only cause a few severe storms.  Issuance of a watch is not likely at this time.  Rain will spread northeast on Friday across portions of the Mid-Atlantic and lower Great Lakes. Farther south, another round of showers and thunderstorms is expected to develop during the afternoon and evening along the Gulf Coast, some of which could once again become severe across the lower Mississippi Valley and adjacent Gulf coastal areas.  Primary convective development may occur in response to strengthening low-level warm advection on the leading edge of the deeper/more favorable low-level moisture return.  This is expected across parts of the northwestern Gulf of Mexico/upper Texas and Louisiana coastal areas Friday evening, northeastward through portions of southern Louisiana and central Mississippi Friday night, primarily as a risk for severe hail.  By late Friday night, forcing for ascent may become strong enough southward toward southeast Louisiana/Mississippi/Alabama coastal areas, to overcome inhibition and support increasing convective development.  In the presence of increasing boundary layer based instability, the risk for supercells with potential for tornadoes, in addition to large hail and damaging winds, may increase by or shortly after Saturday morning.

Meanwhile, A Pacific frontal system will move onshore along the West coast tonight, bringing widespread rain and mountain snow.  As the system moves inland, snow will spread into portions of the Great Basin and Four Corners region on Friday as this system becomes one of the significant storms expected to impact the states.  Winter Storm Warnings are in effect and some of the higher elevations could see as much as 4 feet of snow fall as this system passes through.    For lower elevations, rain and wind will be the issue with many counties under High Wind Warnings.    Some areas in this region have already seen as much as 6 inches of rain over the last few days and flooding is an issue.   Scattered convective development appears possible during the day Friday, in the presence of lower/mid tropospheric warm advection. The convective layer may be sufficient for low topped supercells, with a risk for strong surface gusts and perhaps a tornado.  The severe threat dies out overnight Friday but heavy snow will be possible through Saturday morning for the mountains in California as well as areas from the Mogollon Rim to the central and southern Rockies.  By late Saturday into Saturday night, rain and mountain snow will begin to increase once again from central California northward along the coast as another frontal system approaches from the Northwest.  Rain and snow will start first in Washington and Oregon before shifting south across California and the Rockies.   Winter Storm Watches are already beginning to go into effect for this system with the forecast calling for an additional 1 to 3 feet in the higher elevations.

 

On Saturday, widespread showers and thunderstorms are once again expected from the Gulf Coast and lower Mississippi valley to the Southeast along and ahead of a developing warm front.  Some storms could become severe by Saturday night and Sunday morning as the trough that’s currently moving onto the west coast shifts east across the Southern Plains by Saturday evening.  Any storms that form here will do so in an environment with steep midlevel lapse rates, moderate buoyancy, and sufficient deep-layer shear for supercells capable of producing large hail (potentially some very large) and damaging winds.  The stronger low-level wind profiles are expected farther east and overnight in association with a lead speed max progressing inland from the Gulf.  Enhancement to low-level shear from south and southeast AL into the FL Panhandle and southwest GA will favor supercells with damaging winds and potentially some tornado risk, depending on the details on the low-level shear and near-ground lapse rates inland.  The Storm Prediction Center has given this area a slight risk at this time but I expect that this will increase as the forecast period gets closer.

Model guidance continues to show a fair amount of uncertainty with the significant storms at the end of this weekend.   The system will be lifting from the Lower Mississippi Valley to the Northeast early next week and could potentially become a significant east coast storm, bringing severe weather to the Southeast and heavy precipitation through New England as the next system moves on shore from the pacific.   The timing and strength of the significant storms has below average confidence at this time, but that will improve as we get a better look at the storm systems involved as they move over land.  There is likely to be a large number of people who will see rain or snow to start next week.

 

Rob

 

2 storm chances for East Coast

The Southern Storm is the big story with winter weather expected to impact from Texas to the Eastern Seaboard, leaving the first storm expected to form off the coast of the Carolina’s pretty much no attention attention.

 

This weak system is expected to slide up the coast and bring some rain to Eastern North Carolina with light snow from areas of Nebraska into Kentucky to Delaware and New Jersey ahead of the Southern Storm.  Matt has posted a handy map of the Winter Weather Advisories that are currently in place as this weak system moves across the country toward the coast.   This system will combine with the low shown above and slowly intensify as it moves to the Southeast of New England.  This system will bring snow into Southeastern New England with light accumulations during the early morning hours of Friday into Friday afternoon.    Early activity will likely be in the form of snow showers which may limit to coverage area of overall snowfall but the biggest problem to accumulating snow will be the warmth of the ground.   Any snow that does manage to stick will have a difficult time remaining in place for long, with the one thing that may save some areas from an instant melt being the cold temperatures on the way following this system.

Southern Storm

For the main event, which have been covered well by Chris and Matt for the Southern areas that’s will be impacted, the Southern storm looks like it’ll be wide right for many of our readers.  As seen in the previous articles, the system forms in the South and slides off the coast of the Carolina’s, leaving the heavier snow totals expected for that region.  the uncertainty in the speed and exact track of this system is causing some forecast issues, but aside from some lake effect snows  caused by the general flow pattern in the Great Lakes region, this second system looks to leave readers across most of Kentucky, West Virginia, Western and Central Pennsylvania back towards Ohio high and dry.

Southern Storm

The above model data is for 1 PM Saturday.   It shows the storm after it has left Georgia and areas further west and does not indicate that it will not snow there at all.  Just that it will not be snowing there at this particular point in time.

Watching the strength and track

The key question to the track of this system will be the strength of the lows and the energy brought into the pattern.  A strong set up will include more of the Eastern portions of the U.S while a weaker pattern will deprive even New England of any snowfall.  Despite the impressive moisture associated with this system, guidance is now really strengthening these lows very much.   For anyone along the Mid-Atlantic and Northeast, please read the articles Matt and Chris put out about the south to stay informed about this system.   The information they have will be invaluable for track this system up the coast over time.   I’ll be around to keep you up to dat on all the latest for this system and its impacts for this region.   So keep an eye on both facebook and the website for further details.

 

Robert Millette

Firsthand Weather

Matthew downgraded to Post Tropical Storm

Satellite and radar imagery show that Matthew has continued to degrade and is now a Post Tropical Storm.  Matthew’s center is now exposed to the wind shear that has begun affecting him with no deep convection near the center.  Despite this, strong winds continue across Eastern North Carolina this morning with winds just southwest of the center still sustained at hurricane force.

A motion toward the east-northeast or east is expected for the next couple of days. On the forecast track, the center of Matthew will move farther offshore of the coast of the North Carolina Outer Banks today and tonight.  Maximum sustained winds are near 75 mph with higher gusts. Hurricane-force winds extend outward up to 70 miles, mainly to the southwest of the center, and tropical-storm-force winds extend outward up to 240 miles. A sustained wind of 61 mph and a gust to 79 mph were recently measured by a National Ocean Service instrument at Duck, North Carolina. A wind gust to 90 mph (127 km/h) was measured at an elevated private weather station near Nags Head, North Carolina and a wind gust to 70 mph (113 km/h) has been observed at Dare County Airport near Manteo, North Carolina. . The estimated minimum central pressure is 984 mb (29.06 inches).

matthew

Hurricane Hunters

An air force reserve reconnaissance mission completed this morning continues to indicate hurricane force winds were occurring, but not over land.

Surface observations indicate that the cold front should overtake Matthew shortly and push Matthew east with no loop occurring towards Florida.  Matthew should undergo his extra tropical transition when this occurs before he dissipates.

 

Watches and Warnings:

A Hurricane Watch is in effect for North of Surf City to Duck North Carolina including the Pamlico and Albemarle Sounds

A Tropical Storm Warning is in effect for Cape Fear to Duck North Carolina including the Pamlico and Albemarle Sounds

Flood Warnings and High Wind Advisories are in effect for most of North Carolina and Southeast Virginia.

 

As Matthew’s structure changes, the system’s strongest winds continue to shift to the west side of the circulation. The winds are expected to increase significantly over the coastal areas of eastern North Carolina during the next several hours, and during the next 6 to 12 hours there is the possibility of near-hurricane force winds over the North Carolina Outer Banks, as well as the Pamlico and Albemarle Sounds. There is also an increased threat of storm surge in these areas.

Matthew Hazards:

 

WIND: Tropical storm conditions are expected to continue over the warning area through early this afternoon, and then gradually diminish by this evening. Hurricane-force wind gusts should continue through this morning over the North Carolina Outer Banks.

STORM SURGE: The combination of a dangerous storm surge, the tide, and large and destructive waves will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water could reach the following heights above ground if the peak surge occurs at the time of high tide Surf City to Duck, North Carolina, including portions of the Pamlico and Albemarle Sounds could see surge tides of 3 to 5 ft

The deepest water will occur along the immediate coast in areas of onshore winds. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances. Large waves generated by Matthew will cause water rises to occur well in advance of and well away from the track of the center. There is a danger of life-threatening inundation during the next 36 hours along the coast from Surf City to Duck, North Carolina, including portions of the Pamlico and Albemarle Sounds.

RAINFALL: Matthew is expected to produce additional rainfall accumulations of 1 to 3 inches across southeast Virginia and extreme eastern North Carolina through this morning. Storm total rainfall of 6 to 12 inches, with isolated amounts up to 20 inches, continues to result in life-threatening flooding and flash flooding across the region.

SURF: Swells generated by Matthew will continue to affect much of the southeastern and Mid-Atlantic coasts of the United States during the next couple of days. These swells will likely cause life-threatening surf and rip current conditions.

 

Robert Millette

Severe weather to strike again in Northeast

The severe weather simply refuses to quite down in the Northeast as we move into what we expect to be our third day of severe weather in 4 days.  The past week has seen New England experience 4 Tornadoes in New Hampshire and Maine, though all were thankfully weak and In mostly uninhabited regions.

Currently, a shortwave trough moving through Ontario is expected to move into Southern Quebec by Monday.  A mid-level disturbance is moving around the bottom of this shortwave and the disturbance will induce height falls at the 500 millibar level through Monday afternoon into Monday night, increasing the overall instability of the region.  A cold front associated with the trough will move through the Great Lakes region into New England with the trailing southern portion extending through the Ohio River Valley back into Arkansas and Oklahoma.

image

Severe Summary

Southwesterly flow ahead of the trough and cold front has been working to moisten the air across Pennsylvania and New York.  This moist air is spreading into the Hudson River Valley and will expand across much of Western and Southern New England through Monday afternoon.  Dew points are expected to climb well into the 60s at the surface with some locations approaching 70 degrees.  There will be an elevated mixed layer between 700 and 500 millibars that should spread east atop this moist air which should allow for cumulonimbus clouds to build to very high heights for this area, especially across Central and Eastern New York, Northeast Pennsylvania and Western areas of New England.

There may be some limiting factors to overall destabilization if some early period convection and cloudiness occurs to limit day time heating, but moderate to high mid to upper-level cape (convective available potential energy) and strong forcing from the cold front is expected to help overcome any deficiencies that may occur from areas of limited heating.  Strengthening deep layer shear is also going to be a factor and the increasing shear conditions over New York and Northern Pennsylvania as well as Western and Central New England should bring higher severe weather risks.

Strengthening westerly winds with height suggest organized storms will be possible, with some splitting of storms occurring.  Damaging winds will be the primary threat though some hail cannot be ruled out.

 

Robert Millette

Staff Meteorologist

Firsthand Weather

 

Sunday Severe Storms

Showers and thunderstorms are ongoing across parts of Oklahoma and northern Texas this morning. This activity will continue to progress towards the east throughout the morning hours before new activity ignites. A cool front is slowly pushing into central Oklahoma this morning, coupled with a shortwave trough rapidly approaching the area; this will be the focus for new thunderstorm development this afternoon.
Slide02
HRRR Simulated Radar For This Afternoon

Some of these storms will likely be strong to severe and the Storm Prediction Center has a slight risk for severe thunderstorms for most of eastern Oklahoma. Damaging winds, large hail, very heavy rainfall, and frequent lighting will be possible with any thunderstorm.
Slide04
SPC Thunderstorm Forecast (Yellow Area: Slight Risk)

The heaviest rainfall will be along and east of I-35. These areas will see .5-1″ of rainfall with amounts as high as 2-4″ towards northeastern Oklahoma.
Slide03
HRRR Rainfall Forecast

If you’re on area lakes today, please remain on high alert in case a thunderstorm approaches your area. Regardless of thunderstorm chances, temperatures will be extremely hot. Heat indices will exceed 100, so stay hydrated out there. Another chance for thunderstorms exists for you 4th of July across parts of Texas and Oklahoma. I’ll have an update on this later this evening.

Southern Plains Storms

Shower and thunderstorm chances will continue across much of Kansas, northern Oklahoma, and the Texas Panhandle over the next few days. Isolated thunderstorms are ongoing across parts of the Southern Plains this evening, but more widespread activity is expected to develop in eastern Colorado/western Kansas and propagate towards northern Oklahoma tonight into early Thursday.

By Thursday evening a weak cool front will advance into Kansas and north of I-40 (in Oklahoma) by Friday morning. This boundary will be the focus for several rounds of showers and storms for Kansas as well as northern and central Oklahoma. Heavy rainfall is likely during this setup; most areas north of I-40 will see 1-2″ with isolated 3-6″ possible. This could create flash flooding for localized areas during the day on Friday. Isolated damaging winds and large hail is possible with any storm over the next few days, and lightning will be a major concern for those who have outdoor plans.
Slide02
Potential Rainfall Totals (Next 5 Days)

It is important to note that the area will see a northerly flow aloft, so some of the thunderstorms that develop in northern/central Oklahoma may move further south than the models indicate. This will keep scattered rain chances in the forecast for southern Oklahoma as well as northern Texas, but the greatest coverage will be north of I-40.

Rain chances will subside for northern Texas and much of Oklahoma on Saturday, but appear to return later in the weekend. These rain chances will be bumped up a few notches on Sunday into Monday due to the upper-level ridge weakening. Temperatures will top out in the 80’s and 90’s the rest of this week so make sure you’re staying hydrated! I’ll have more details on the Monday (4th of July) forecast in the next day or two.

California’s Water Issues Solved?

There has been much talk over the past several years about the severe drought conditions across California. There was a glimmer of hope due to the strong El Nino during the winter, but the pattern failed to deliver beneficial rainfall to California.
Slide02
Current California Drought Monitor (Maroon:Exceptional, Red:Extreme, Orange:Severe): Courtesy of the United States Drought Monitor

However, there’s a new glimmer of hope as of this week. Stanford University announced the aquifers below the surface of California have substantially more freshwater than previously believed. This report shows as much as three times more freshwater is located in these deep aquifers–equivalent to 2,700 cubic kilometers of groundwater.

This is great news because there has been much worry about the growing drought conditions, paired with the large and increasing population of the State, as well as the massive agriculture production of the State. There are some concerns, however, about the findings from Standford.

The quality of the water is questioned, and the water is at a very deep depth. These aquifers are between 1000 to 3000 feet underground. This makes the extraction of the water very pricey. One other concern is the sinking of the ground that could occur due to the extraction of the groundwater; sinkholes could also develop in the vicinity above the aquifer. Even with these questions, this is ‘cool’ news during a hot Summer!