High-impact storms to create tricky holiday travel

Travelers will be heavily impacted by Mother Nature this week across a large part of the country (see Fig. 1). A potent storm system is taking shape across the Pacific right now and will move into northern California & southern Oregon late Tuesday night, eventually impacting most of the western United States. To give you an idea of the forecast intensity of this storm, it is expected to rapidly deepen and pack winds up to 80 mph (that’s the wind strength of a Category 1 Hurricane).

Fig. 1: Storm threats through Thursday


This storm will move inland Tuesday into Wednesday aiding in heavy mountain snow, valley flash flooding and damaging wind gusts across parts of the West. The California Sierra-Nevadas will be walloped with heavy, wet snow through Thanksgiving. 2-3′ are possible within the higher elevations. Snow levels will drop to 4,000′ as the system begins to depart. The valleys will also receive heavy precipitation. This precipitation will fall in the form of rain. 1-4″ are possible with flash flooding a real threat in the valleys. The greatest flash flood threat, and mudslide threat, exists near burn scars. 


National Weather Service offices have issued numerous winter weather products (Watches, Warnings and Advisories) for the region (see Fig. 2). Oregon, California, Nevada, Utah and Idaho will all see impacts from this storm. As the storm ejects toward the east, impacts will be felt across New Mexico, Arizona and Colorado by late week. New Mexico will see a double punch as moisture off of the Pacific will generate a wintry mixture by Wednesday. This wintry mixture will spread into the Texas & Oklahoma Panhandles. 

Fig. 2: Current western winter weather alerts


The West isn’t the only part of the country dealing with high-impact weather that will impact travel. The Rockies east into the Plains will see moderate to heavy snow accumulations through mid-week as a low develops on the east side of the Rockies. A heavy swatch of snow will occur on the north side of this low extending from Colorado east into Nebraska, southern Nebraska & northern Kansas. Eventually, Iowa, Minnesota & Wisconsin will get in on the action. Widespread 6-12″ are expected in this region with isolated 1-2′ amounts near the Rockies and close to Lake Superior. As this storm intensifies, winds may gust between 40 to 70 mph, which would greatly reduce visibility. Winter weather alerts are in place for part of the Rockies and Plains (see Fig. 3).

Fig. 3: Current Plains winter weather alerts

2019-20 Winter Forecast: A State-By-State Breakdown

Introduction

Each fall, Firsthand Weather releases a winter forecast to explain the large-scale atmospheric and oceanic features that could drive temperature and precipitation patterns during the winter months across the United States. Our goal is to provide you with an overview of what you should expect conditions to be on average. Thus, temperature and precipitation could vary greatly over the three-month winter season, depending on your location. We don’t predict exact snowfall/rainfall totals in our seasonal products. We simply want to inform our viewers if our analysis suggests their region will have anomalous conditions (e.g. above average temperatures, above-average snowfall, etc.). Due to the nature of seasonal forecasting, we may eventually have to modify our original winter forecast for some regions. If that occurs, we will thoroughly explain which aspects of the forecast were wrong and why. Though we have put much time and effort into this winter forecast, we want any errors that we make to be a learning experience for all of you and for us, as well.

Firsthand Weather’s official 2019-20 Winter Forecast

Technical discussion about analog selection

Before writing any seasonal forecast product, we perform an analysis to select previous winters that appear to be similar to the upcoming one. We refer to those similar winter seasons as analogs. One method that we use to accomplish this task is to select similar years based on sea surface temperatures (SST) anomalies in the north Atlantic and Pacific Oceans. An anomaly is simply a departure from average of some value (e.g. temperature, precipitation, etc.) at a given time or over some specified period. Some years, moderate to strong El Niño or La Niña conditions are evident, which makes it a bit easier to find years that had similar oceanic and atmospheric conditions. But as shown by SST anomalies over the last month, there really is no strong El Niño or La Niña signal (Figure 1). Strictly based on oceanic conditions, there are some hints of an El Niño Modoki, represented by above average SSTs across the central equatorial Pacific. The most noteworthy feature is the ‘warm blob’ that has persisted south of the Gulf of Alaska, reminiscent of a feature present during the 2013-14 and 2014-15 winters. Also, sea ice extent has recently been at record lows across the Chukchi Sea between Alaska and Russia. Though climate change likely increases the odds of such events occurring, we cannot ignore atmospheric and oceanic conditions elsewhere that could have forced low sea ice extent in the region relative to recent years. We care about Pacific oceanic and atmospheric conditions because those conditions can strongly impact temperature and precipitation patterns over the United States. 

Figure 1: Latest monthly-averaged SST anomalies

For a few sentences, we’re about to get a little technical, but we’ll attempt to explain this as clearly as possible. We decided to deconstruct SST anomalies using empirical orthogonal functions (EOFs) to identify modes of SST anomaly variability. When we’re talking about SST variability, we’re simply referring to how much SSTs vary over some period of time. El Niño and La Niña explain one mode of SST variability in the Pacific. However, some modes of variability may be difficult to identify without using a statistical method like EOFs to pull them out, which we can then use to find years that had similar SST patterns. A more obscure mode of variability in the Pacific is represented by the ‘warm blob’ over the northeast Pacific. When the warm blob exists, SSTs are usually above average across the west-central equatorial Pacific, as well. We can actually outline this signature in the monthly SST anomalies in the first figure. Since we know that conditions along the equatorial Pacific can affect atmospheric conditions in the U.S. and that the warm blob may be connected to the equatorial Pacific, we simply can’t ignore the relatively high SSTs in the northeast Pacific. Furthermore, if the warm blob persists throughout the winter, it’s not unreasonable to suggest that it could strengthen large-scale ridging over the region; thus, having an even greater effect on U.S. winter conditions. We’ll provide a follow-up article or video to break down our methods further in a couple of weeks.

If the last paragraph was a bit too technical for your liking, we promise that we’re finally going to share our analog years, which will lead into the actual forecast. We initially pinpointed three winters where the northeast Pacific warm blob persisted through most of the winter (1956-57, 1967-68, 2013-14). The issue with using the 1956-57 winter as an analog was that there was a ring of cooler SSTs extended from the Bering Sea to the Gulf of Alaska/West Coast and over to Hawaii (Figure 2). Although the northeast Pacific warm pool existed that winter, another mode of SST/atmospheric variability, known as the Pacific Decadal Oscillation (PDO), was negative. Thus, Southeast ridging dominated that winter, causing temperatures to remain well-above average across the Southeast and Southern Plains. On the other hand, the Pacific Northwest and the northern Great Plains had below average temperatures. At least based on current projections, there’s no reason to believe that the PDO will go into a negative phase this winter, which only leaves us with the 1967-68 and 2013-14 winters (Figure 3) as analogs.

Figure 2: A composite of SST anomalies during the 1956-57 winter
Figure 3: A composite of SST anomalies during the 2013-14 winter

We really needed more analog years to go by since a sample size of two is simply too small. Since current evidence suggested that the Pacific warm blob will persist through the winter, we decided to pull the top five February’s that had a northeast Pacific warm pool and a neutral or positive PDO. We didn’t eyeball this. We used EOFs and principal component time series to select those cases. Those five Februarys included: 1963, 2014, 1968, 2015, and 1930. When making a composite of SST anomalies of those five winters from December-February, we found that anomalous warming existed over the northeast Pacific, along with no evident PDO signature (Figure 4). Of course, the reality is that SSTs are considerably higher today across the North Pacific compared to some of our analog years, but given the nature of this science, we have to work with what we’ve got and learn from there!

Figure 4: A composite of SST anomalies during five analog years

We made a 500mb anomaly height field composite using our five analogs years to identify the large-scale characteristics most prominent during those winters (Figure 5). It appears that ridging likely existed along the West Coast and extended into Alaska and the Bering Sea. If we take those same years and plot surface temperature anomaly composites, we find that those winters were characterized by widespread cold across the eastern two-thirds of the nation and above average temperatures across the southwestern U.S and Alaska (Figure 6 & 7). We can’t discount the possibility that the spatial distribution of SST anomalies in the North Pacific will change markedly throughout this winter. However, our current findings, assuming that SST anomalies in the North Pacific remain similar throughout this winter, suggest that we could experience a winter similar to 2013-14. If sudden changes in Pacific SSTs do occur, the likelihood of our winter forecast verifying in some regions will greatly decrease.

Figure 5: A composite of 500mb height anomalies during five analog years
Figure 6: A composite of 2m (surface) temperature anomalies during five analog years
Figure 7: Same as Figure 6 except focused over the Lower 48

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2019-20 Winter Forecast Regional Breakdown

California, Nevada: Drought conditions have already begun to develop across most of California and Nevada, except for the extreme northern part of each state. Although the Pacific and subtropical jets should remain active through early December, the upcoming uptick in rainfall and mountain snow for the northern half of these states will likely not persist through January and February. Throughout the winter, large-scale ridging should become a dominant feature along and just off the West Coast and into Alaska. Therefore, this should keep the primary storm track well to the north of the region. Furthermore, temperatures should end up above average for the region, even despite the possibility of early-season cold air intrusions. Concerns remain that the lack of precipitation this winter could result in an ongoing and increased wildfire threat this spring.

Washington, Oregon, Idaho, Montana: Although the active Pacific jet could usher in a few noteworthy storm systems early in the season, the placement of the ridge should eventually prevent most systems from moving into Washington and Oregon in a west-to-east fashion. Instead, the ridge will result in shortwaves dropping down into Montana in a northwest-to-southeast fashion. Now, here’s a disclaimer. If the ridge builds farther offshore or is more zonal in nature, then the pattern would be much more active across the Pacific Northwest. However, our current findings do not suggest this will occur. We expect temperatures to be average to above average across Washington, Oregon, and Idaho. Precipitation should remain below-average for most of the winter across the three states, and the Cascades and northern Rockies will have below-average snowfall for the season. The eastern two-thirds of Montana will likely be the exception to the rule. We expect precipitation/snowfall, east of the Rockies, to be around average for that part of the state, and temperatures to be average to below-average.     

Wyoming, Utah, Colorado: Temperatures will generally run above average to the west of the Rockies, while temperatures will be average to below average along and east of the Rockies. Although we expect the early winter to start off more active than the middle and end will be, snowfall totals will be slightly above average along and east of the Rockies, including for Denver, CO and Cheyenne, WY. The mean axis of the western ridge will likely remain positioned far enough west to prevent conditions from drying out too much later in the season from the Rockies eastward. Thus, we don’t expect a situation similar to the 2014-15 winter when large-scale ridging was positioned just too far east over the West to allow for a really good ski season over the Rockies. However, a lack of precipitation will exacerbate already-existing drought conditions west of the Rockies, especially over Utah. We expect snowfall totals to run below-average across Salt Lake City, UT and for most of the state.

Arizona, New Mexico: Drought conditions still exist over both states, with some regions at severe or even extreme drought. Despite the tendency for ridging over the West, a split-flow pattern likely will allow storm systems to pass through and strengthen over the region early in the winter. However, the winter should progressively get drier from mid-to-late season, worsening drought conditions for most. We expect precipitation to be average to below average, except across the northern half of New Mexico. Snowfall totals across the Rockies and outside of the mountains into eastern New Mexico should run around average or even slightly above average. Temperatures will generally run around average to slightly above average across the rest of New Mexico, while they will run mostly above average across Arizona.

Missouri, Illinois, Indiana, Ohio, Kentucky: Almost this entire region will experience temperatures either below average or well-below average. Large-scale troughing will become a dominant feature over the area this winter, allowing numerous rounds of Arctic air to flow into the region. Early in the season, a tendency for ridging across the Southeast and an active subtropical jet will provide a few opportunities for heavy precipitation events (rain and/or snow). Unlike last year, Southeast ridging will likely not build as strongly into the region; thus, temperatures will not have the tendency to run above average for long periods of time. Snowfall totals for the winter should at least end up around average with many areas experiencing above average snowfall. Overall, this winter will be characterized as active and consistently cold (relative to average) across these states. Conditions will be especially frigid over places like Chicago, IL.

Arkansas, Louisiana, Tennessee, Mississippi, Alabama, Georgia, North Carolina, South Carolina, Florida: Many in this region will have their first opportunity in several winters to experience at least several weeks of anomalous cold weather, if not a bit longer. Although early-season Southeast ridging could make it challenging for many areas outside of the Appalachians to receive frozen precipitation at first, that should begin to change either in late December or early January. The primary storm track early in the season should remain west and north of the region, allowing for several periods of rainy conditions. Thus, there will be alternating periods of cool/wet and cold/dry conditions during that time. As the season progresses, a tendency for large-scale troughing over the eastern U.S. will allow several rounds of Arctic air to intrude into the region. Temperatures should run below-average across most of this area, except over the Florida peninsula around and south of Orlando. For most regions that experience frozen precipitation every few years or more often, snowfall and/or ice accumulations should run average to above average. The Appalachians will likely experience above-average snowfall.

North Dakota, South Dakota, Nebraska, Iowa, Minnesota, Wisconsin, Michigan: Although it generally goes without saying that the northern Great Plains, Midwest, and Great Lakes will have a cold winter, these regions will experience conditions much colder than average. The Great Lakes region will especially experience dangerous cold and will probably end up with the largest departure from average temperatures when all is said and done. The pattern will support ample lake-effect snow, especially early in the season when the lakes contain less ice-cover. Early on, the primary storm track will be oriented from the middle Great Plains to the Great Lakes, which will place most of these states on the snowy side of any system that passes through the region. Eventually, large-scale troughing will become a dominate feature, and the mean trough axis should position this region to receive snow relatively often from northern stream systems. Thus, snowfall totals should at least reach average levels, if not above average. Those locations prone to lake-effect snowfall should have above-average snowfall this season.

Kansas, Oklahoma, Texas: The panhandles of Texas and Oklahoma, along with most of Kansas will have several good opportunities to receive snowfall early in the season, and such an early start to winter may allow that region to end up with above average snowfall for the winter. Multiple intrusions of Arctic cold should make it into the area at the beginning of the season, and colder conditions should persist through most of the winter, even if temperatures move back closer to average later in the winter. Yes, that includes the entire state of Texas. Areas closer to the Red River, including regions as far south as Dallas, TX, could have a couple of really good shots at receiving accumulating snow/ice later this season. Thus, we expect average to above-average snowfall across much of Oklahoma and for areas along a line that extends as far south as Dallas, even if liquid-equivalent precipitation remains around average.

West Virginia, Virginia, Maryland, Delaware, New Jersey: This region will have a decent shot at snowfall this year, and conditions should remain consistently colder than average due to large-scale troughing. We don’t expect southeast ridging to be as strong as last winter; thus, expect numerous intrusions of bitter cold to make it into the region this winter. Interior regions closer to the mountains will experience snowfall early this year, primarily due to the likelihood of northwest flow events. Early on, the storm track will orient itself from the Great Plains to the Great Lakes/New England region, which could hurt snow chances at the beginning of the season. However, by the end of the season, snowfall totals should at least approach average values for most locations. In order for the Mid-Atlantic coastal regions to experience well-above average snowfall totals, blocking (ridging) generally needs to occur over Greenland for an extended period of time (e.g. 2009-10 winter). Unfortunately, predicting such a block remains challenging and is something we’ll have to monitor throughout the winter.

Pennsylvania, New York, Connecticut, Massachusetts, Rhode Island, Vermont, New Hampshire, Maine: We expect this entire region to experience temperatures below average this winter; however, the largest departures from average will likely occur closer to the Great Lakes in New York and Pennsylvania. Regions prone to lake-effect snow will experience above average snowfall this winter, with the bulk of the lake-effect snow falling early in the season when the lakes will be mostly ice-free. Although liquid-equivalent precipitation may end up closer to average for most locations, the cumulative effect of storm systems passing through the region from the Great Plains early in the season, along with northern stream systems bringing additional snow, should allow snowfall totals to reach above-average levels for interior regions. Closer to the coast from around Philadelphia to New York City to Boston, snowfall totals will come closer to average; however, temperatures will still end up below average due to persistent troughing over the region.  

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Thanksgiving Weather Forecast

With Thanksgiving around a week away, it’s time to begin taking a stab at the forecast. Over the next seven days, a parade of storm systems will ride along an active Pacific jet stream into the Pacific Northwest. These various shortwaves will dig southeastward into the Rockies, inducing the development of a couple of surface low pressure systems that will deepen over the Plains next week. Such a scenario will help maintain a trough over the western half of the U.S., while ridging will attempt to build across the eastern third of the U.S. downstream of the trough around Thanksgiving.

Confidence is relatively high that an active pattern will persist across the Pacific Northwest before and during the Thanksgiving holiday. This pattern will favor snowy conditions across the Cascades and the Rockies next week. On Thanksgiving Day or the day before, the Sierra Nevada Mountains may have accumulating snowfall thanks to a shortwave that could manage to dig as far south as Northern California. Overall, the pattern will favor snow falling as far south as the mountainous regions of Arizona and New Mexico. Cities just outside of the Rockies like Denver, CO and Cheyenne, WY will receive accumulations, as well. In other words, if you’re wanting to have at least a couple decent shots at seeing snow around Thanksgiving, head west!

Ridging will likely try to hang on across the Southeast and along the eastern U.S. coast. Thus, any storm system moving in from the West will trek northeastward across the Great Plains before reaching the Great Lakes region. This will leave the southeastern U.S. and East coast with wet conditions ahead any cold front that moves through the region. I don’t anticipate any frozen precipitation falling south of a line that extends from northern Oklahoma/Texas Panhandle to Kansas/Missouri. The Dakotas, Nebraska, the Midwest, and Great Lakes will be fair game for heavy winter precipitation next week. Illinois, Indiana, and Ohio should expect an active pattern throughout Thanksgiving week, but uncertainty remains low in regard to how much frozen precipitation will occur across those states. I will address those probabilities on a system-by-system basis next week.  

Temperatures across the Mid-south, Southeast, Mid-Atlantic, and even New England will likely be quite volatile over Thanksgiving week due to the storm track. Although a couple of cold fronts will likely move through most of these regions, warm air advection will occur ahead of any storm system that treks across the Great Plains and Great Lakes region. Mostly, conditions will alternate between cool/wet and seasonably cold/dry. In other words, the pattern will remain active during Thanksgiving week across these regions, and I currently can’t guarantee that many won’t experience cloudy and wet weather on Thanksgiving Day.

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The featured image used in this article is courtesy of @thesmartease.

Arctic cold front to shatter records & aid in wintry precipitation

A large dip in the jet stream will send an Arctic cold front deep into southern parts of the country by early this upcoming week (Fig. 1). The cold front will move through the Southern Plains late Sunday night (tonight) into Monday; followed by the front rapidly advancing into the South & Southeast Monday night through Tuesday. The airmass behind this front is extremely cold for this time of the year and will be the coldest air of the season. Millions of people will experience below-freezing temperatures, including down the the Gulf of Mexico, and many records are at risk of being shattered (see Fig. 2). Temperatures will be 10-30 degrees below average.

Fig. 1: Big dip in jet stream early week
Fig. 2: Record cold temperatures for millions possible

Southern Plains

The Arctic cold front will push south Sunday night (tonight) into early Monday morning for Oklahoma and northern Texas. Temperatures will rapidly fall below freezing behind the cold front as northerly winds of 30-45 mph usher in the cold air. Wind chills by Tuesday morning will fall into the teens & 20s for a good part of Oklahoma and Texas (see Fig. 3). High temperatures will struggle in the 30s & 40s with lows in the teens & 20s through mid-week. Along with the cold temperatures & wind, post-frontal precipitation will occur. Some of this post-frontal precipitation will fall in the form of freezing drizzle & sleet Sunday night, and eventually some light snow by Monday across the Texas Panhandle, central & northern Oklahoma and northern Arkansas (see Fig. 4 & 5). Minimal accumulations are expected but a few slick spots may develop along I-40 from the Texas Panhandle east into northern Arkansas.

Fig. 3: Wind chills Tuesday morning
Fig. 4: Future radar 10:30 am Monday
Fig. 5: Future radar 1:30 pm Monday

As the cold airmass moves south & east late Monday into early Tuesday, some of the post-frontal precipitation may briefly change into a wintry mixture for parts of central Texas & the Texas Hill County (see Fig. 6 & 7). Right now, minor accumulations are expected but a few slick spots may develop.

Fig. 6: Future radar 12:00 am Tuesday
Fig. 7: Future radar 8:00 am Tuesday

Southeast

The South & Southeast will get in on the cold airmass by Tuesday. This will knock high temperatures into the 30s & 40s through mid-week with lows in the 20s & 30s. A very brief period for light freezing drizzle or sleet may occur late Monday night into early Tuesday morning across northern Mississippi, northern Alabama and northwest Georgia (see Fig. 8, 9 & 10). The window for freezing/frozen precipitation is short for Mississippi, Alabama and Georgia and most areas should not see accumulations. Farther north into Tennessee, a longer duration & colder temperatures will allow for light to moderate snow accumulations (see Fig. 11). By Wednesday morning, wind chills will be in the teens & 20s for a large part of the South & Southeast (see Fig. 12).

Fig. 8: Future radar 11:30 pm Monday
Fig. 9: Future radar 3:00 am Tuesday
Fig. 10: Future radar 5:00 am Tuesday
Fig. 11: Snow accumulation forecast through Tuesday
Fig. 12: Wind chills Wednesday morning

A response to questions about snow next week

Many of you have heard rumors of snow. Let’s talk about that. We’re over 3 weeks away from the start of meteorological winter, yet next week’s setup is very impressive for this time of year. In my opinion, the real story will be the cold. Most regions along and east of the Rockies will experience temperatures that would be expected during the winter.

Projected temperatures at 7am ET on Nov. 13 2019
Projected temperatures at 7am ET on Nov. 14 2019

Our first frontal passage is moving across the country now. If you check out current U.S. temperatures, you can see the cold front quite nicely. All of the snow talk is about the second cold front moving through early next week. That’s going to bring the real cold.

Basically, a strong mid-to-upper level trough is going to become oriented from southwest to northeast, extending as far south as Texas and Mexico. A strong cold front will be associated with the trough, and a surface low will likely develop to the east of the trough axis. It’s very possible that this surface low will track along the Gulf Coast states, exit off the Southeast coast and skirt parts of the East Coast.

There should be the development of precipitation along and ahead of the cold front. Due to the potency of the air mass moving in behind the cold front, most model guidance shows a transition from a cold rain to snow and sleet on the backside of the precipitation shield. As shown by the European model, you will notice accumulations occurring unusually far to the south. Other models have shown this as well.

Projected snowfall accumulations early next week, a forecast that will likely change significantly between now and then
Projected snowfall accumulations early next week, a forecast that will likely change significantly between now and then

When I’m looking for decent snow accumulations to occur farther south, I like to see a well-developed surface low pressure system. When a trough is oriented from southwest to northeast, the surface low generally remains weak. Thus, any frozen precipitation basically has to occur along a frontal boundary without any well-defined low. It does happen, but a setup like this doesn’t usually produce a big winter storm. Remember when Firsthand Weather busted horribly on a winter storm forecast last year? We expected accumulating snowfall to occur along a strong cold front without a well-developed surface low. We blew the forecast.

I’m a bit more concerned about temperatures dropping rapidly while roads are still wet. Oftentimes, roads are able to dry before temperatures reach freezing, but again, the air mass behind next week’s front is potent. Remember, temperatures will be at levels that we’d typically experience during winter. Some of the model guidance strengthens the surface low off the Southeast coast; thus, I’m not willing to discount accumulations being depicted across parts of North Carolina, Virginia, and northward along the coast just yet.

My hope is that many of you will get to experience a little snow. I suspect that accumulations won’t occur anywhere south of a line that runs from Oklahoma, central Arkansas, Tennessee, and North Carolina. Again, any concerns south of that line would likely be due to black ice, which can be quite dangerous.

I’ll post a more in-depth forecast on the site, if needed. I believe we need to watch everything a couple more days before we put out any detailed forecasts.

Several cold blasts on the way

November is off to a cool start for much of the northern-half of the country and more cold weather is in the forecast. Numerical guidance continues to indicate much of central & eastern parts of the country will remain below average through mid-November.

The upper-level pattern will favor cold shots of air from the Arctic down into the United States as the jet stream takes a deep equatorial dive. This big dip in the jet stream will allow the cold air to seep farther south and southeast by late this week week into the weekend. High temperatures will be 10 to 30 degrees below average for the aforementioned areas. A good part of the Southeast will see highs fall into the 40s & 50s with lows in the 30s from Friday through Sunday.

Fig. 1: Dip in the jet stream

At this time, guidance is indicating another strong push of cold air will dive into central and eastern parts of the country early next week. This airmass looks to be even colder than the late-week surge. It is too early to determine just how cold it will get and where the brunt of the cold air will move but all indications are for a chilly airmass impacting a good part of the country east of the Rockies. It appears the Southeast will see pretty chilly air with highs possibly in the 40s & lows in the 20s.

The Climate Prediction Center indicates much of the eastern and central United States will see high probabilities of below average temperatures for days 6 through 10 and days 8 through 14.

Fig. 2: 6-10 day temperature outlook
Fig. 2: 8-14 day temperature outlook

Check back tomorrow for a detailed update from Matthew on the big cool down!