Today Through the Fourth Friday (22 to 28 days) Weather Outlook for the U.S. and a Six-Day Forecast for the World: posted September 3, 2024
This article focuses on what we are paying attention to in the next 48 to 72 hours. The article also includes weather maps for longer-term U.S. outlooks and a six-day World weather outlook which can be very useful for travelers.
First the NWS Short Range Forecast. The afternoon NWS text update can be found here after about 4 p.m. New York time but it is unlikely to have changed very much from the morning update. The images in this article automatically update.
Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Tue Sep 03 2024
Valid 12Z Tue Sep 03 2024 – 12Z Thu Sep 05 2024…Areas of heavy rain and the potential for flash flooding continue in
Texas and along the Gulf Coast the next couple of days……One more day of late-Summer heat for the north-central U.S. Tuesday
before focus shifts to a building heat wave in the West Wednesday…Thunderstorms capable of producing heavy rainfall will persist across
portions of Texas and along the Gulf and southeastern Atlantic Coasts this
week as very moist Gulf air pools around a quasi-stationary frontal
boundary lingering through the region. A passing upper-level disturbance
will lead to more widespread storms once again today (Tuesday) over
portions of central Texas where a locally greater threat for some flash
flooding will exist, with a Slight Risk of Excessive Rainfall (level 2/4)
outlooked for the region. Further east along the central Texas Gulf Coast,
very moist, onshore flow aided by a stubborn coastal low and continued
rounds of storms moving inland will bring further heavy downpours that
could lead to several inches of rainfall. A Slight Risk of Excessive
Rainfall has been included here as well as wet antecedent conditions from
rainfall over the past few days will increase the threat for some
additional instances of flash flooding in the area. The upper-level
disturbance will lift northeastward on Wednesday, increasing storm
coverage over the central Gulf Coast and possibly north into the Lower
Mississippi Valley. Another Slight Risk of Excessive Rainfall is in place
given the threat for heavy downpours and scattered flash flooding. Storms
will also increase along the southeastern Atlantic Coast by Wednesday, and
daily thunderstorm chances will continue for the Florida Peninsula.Further north, an upper-level trough and associated surface cold front
will bring showers and thunderstorms to the northern Rockies today. Some
locally heavy downpours will be possible with an isolated threat of flash
flooding over central Idaho and southwestern Montana. Ahead of this
system, an upper-level ridge over the northern/central High Plains will
lead to another day of well above average, hot late-Summer temperatures,
particularly over the northern High Plains. Forecast highs are into the
90s, with some upper 90s possible for the western Dakotas. The approaching
system from the west will help to bring temperatures back down to average
Wednesday, with highs in the low to mid-80s. Showers and storms are
expected with the passage of the system, particularly over the central
High Plains. Storms chances will also spread into the Upper Midwest as the
system continues east Wednesday night.Attention in the mid- to late week will turn to a building heatwave over
the West. A strong ridge will settle in over the West Coast following the
passage of the upper-trough over the northern tier, with highs on Tuesday
already beginning to climb into the upper-90s and low 100s over interior
California and 100s to 110s in the Desert Southwest. Then, on Wednesday,
temperatures will soar into the low 100s over interior California and into
the 90s in the Pacific Northwest. While not as hot, much above average
temperatures are expected for coastal areas too, with highs into the low
80s for some locations. Heat-related warnings and advisories have been
issued for the Desert Southwest and central/southern California outside of
the immediate coast given a heightened risk for heat-related illness,
especially for those without access to effective air conditioning.
Elsewhere, most of the eastern U.S. outside of the the South will be dry
with generally mild temperatures. Early Fall-like highs in the 70s are
expected throughout New England, the Mid-Atlantic, and Carolinas.