Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
344 AM EDT Thu Sep 19 2019

Valid 12Z Thu Sep 19 2019 - 12Z Sat Sep 21 2019

...Tropical Depression Imelda producing extreme rainfall for parts of
Texas...

...Above average temperatures over the Plains and Midwest and cool for the
West...

The overall weather pattern across the continental U.S. will be rather
amplified aloft through the end of the week with an upper level ridge
encompassing the eastern half of the nation, a closed low off the East
Coast, and a big upper level trough over the western U.S., along with a
strong cold front crossing the Intermountain West.

The upper level ridge is expected to result in temperatures on the order
of 10 to 20 degrees above average from the western High Plains to the
Great Lakes region. The western U.S. trough should keep below average
temperatures in place from the West Coast to the Rockies, with snow likely
for portions of the northern Rockies as the upper level trough axis moves
across that region. For the Mid-Atlantic and Northeast, a high quality
airmass is anchored in over the region as a strong surface high from
Canada governs the overall weather pattern, making it feel more like
autumn compared to last week with lower dewpoints and cooler temperatures.

Tropical Depression Imelda continues to make weather headlines across
eastern Texas.  Extremely persistent thunderstorms on the southern flank
of the system are producing prolific rainfall and dangerous flash flooding
across portions of southeast Texas Thursday morning. A High Risk for
excessive rainfall and flash flooding is in effect for parts of these
areas on Thursday, with the potential for an additional 6 to 12 inches of
rain with isolated higher amounts possible. Storm total rainfall could be
in excess of two feet for some areas before the weather finally begins to
improve!

D. Hamrick


Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php