Forecast and Severe Outlook: Sunday, May 1st

Today’s forecast brings rain to the East Coast and another risk of severe weather to the Gulf Coast.  Heavy rain will bring several Texas waterways back into moderate to major flood stage for a short time with the risk for flooding now spreading into Louisiana.

The current Surface Analysis

Surface map us

 

Today’s National Forecast

Weather Forecast map

A front extending from the Lower Great Lakes to the Western Gulf Coast will become quasi-stationary with the boundary inching to New England Coast southwestward to the Lower Mississippi Valley by Monday evening. The system will develop showers and thunderstorms from the Ohio Valley to the Lower Mississippi Valley that will move to the Northern Mid-Atlantic Coast to the Lower Mississippi Valley and Western Gulf Coast by Monday evening.  Rain will develop over parts of the Central Plains eastward to the Great Lakes and parts of the Northeast as well as parts of the Northern Mid-Atlantic.  The rain will come to an end over the Central Plains and Middle Mississippi Valley by Monday morning and over the Great Lakes by Monday evening.  The rain will move into Northern New England by Sunday evening.

 

Current Model Analysis

6 hour model

On Sunday, thunderstorms will continue across the Appalachian region. Storms will not be as severe as they have been over the past several days but severe weather will continue to be a threat.  The low bringing this risk to the mountains is very broad, and continues to have rain and snow across Nebraska, Wyoming and Colorado this morning.

Dual disturbances in the Southeast continue to bring showers and some storms to the 4 corners region.

While rain won’t be a big factor in the Northeast early this morning, it will be by this afternoon and most of the East Coast, from Northern Florida up through Pennsylvania and New Jersey will begin to see rain by this morning.

18 hour model

Sunday afternoon, the rain shifts east and is now impacting the East coast from Florida to Maine within this broad circulation.

Rain and snow will begin to let up during the afternoon over the Rockies of Colorado, Wyoming and Nebraska.

A low over Arizona will begin to bring rain and snow to the 4 Corners region as a weak and moisture starved low moves into California with nothin to show for it.

36 hour model

By early Monday, High pressure dominates the West with only the remnants of a cold front draped across the Country from Massachusetts to Texas. A weakening low pressure system will set the stage for what looks to be a very wet week along the East coast.

 

Current Severe Weather Outlook

Fire Weather Update

Fire Weather

No Critical Fire Weather areas

Severe Weather Analysis

Summary

Scattered Strong to severe thunderstorms are possible across Southern and Central Texas and the Central Gulf Coast Region as well as in the Ohio Valley and Central Appalachians.

Severe Outlook

Day 1 Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
MARGINAL 309,811 43,672,165 Houston, TX…San Antonio, TX…Indianapolis, IN…Columbus, OH…Austin, TX…

Analysis

With moderate destabilization forecast from the Ohio Valley to the Central Appalachians, strengthening mid to upper level wind fields will allow for marginally conducive conditions for severe storms.  Deep layer sheer will be strong and supportive of supercells, but lower level wind shear is forecast to me weak.  This will minimize tornadic potential in this area but severe hail and strong surface gusts are forecast in the strongest storms.  These storms are expected to be widely scattered this afternoon and evening.

Along the Gulf Coast, Upper level flow is forecast to be moderately strong between the divergent jet streams. Instability will be high ahead of the advancing frontal boundary which could lead to severe weather development.  While some storms are forecast near Upper Texas and Louisiana Coastal areas, most storms will develop near the higher terrain of the Rio Grande River late this afternoon and evening.

This Week’s Flood Risk

Flood Risk

Yesterday’s Storm Reports

storm reports 2

Robert Millette

Staff Meteorologist

Firsthand Weather