Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
309 AM EDT Mon Oct 23 2017

Valid 12Z Mon Oct 23 2017 - 12Z Wed Oct 25 2017

...Large storm system to affect the eastern half of the nation...

A strong autumn storm system is now in the progress of becoming better
organized as two separate low pressure systems consolidate over the Great
Lakes through early Tuesday.  Potent shortwave energy aloft over the Deep
South is forecast to phase with an approaching upper level trough from the
Upper Midwest, and fueling the development of a large and occluded surface
low that will track from the Great Lakes to Ontario and Quebec.  A strong
cold front will trail southward from this low, and bring a swath of
moderate to heavy rain along with embedded thunderstorms towards the East
Coast by Monday night.  The heaviest rainfall is likely to materialize
across southern Michigan in conjunction with the main surface low, and
also for central New England as deep moisture ahead of the front leads to
1 to 3 inch rainfall amounts.  Some instances of flash flooding will be
possible given the atmospheric set-up.

Elsewhere across the continental U.S., fire weather concerns will continue
across parts of California over the next few days with very dry conditions
and gusty winds expected.  A big heat wave is also in the forecast for
southern California, with widespread 90s and 100s expected through Tuesday
with excessive heat warnings in effect.  Cool and dry conditions will
prevail across the Plains and the Intermountain West with surface high
pressure that is large and in charge.

D. Hamrick



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