Prognostic Meteorological Discussion
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000
FXUS01 KWBC 281855
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
255 PM EDT FRI APR 28 2017

VALID 00Z SAT APR 29 2017 - 00Z MON MAY 01 2017

...SEVERE THUNDERSTORMS AND FLASH FLOODING POSSIBLE FROM PORTIONS
OF THE SOUTHERN PLAINS TO THE OHIO VALLEY...

...HEAVY SNOW POSSIBLE FOR PORTIONS OF THE ROCKIES AND THE
ADJACENT HIGH PLAINS...

...ABOVE AVERAGE TEMPERATURES EXPECTED FOR MUCH OF THE EASTERN
U.S...

SEVERAL TYPES OF WEATHER HAZARDS ARE EXPECTED OVER THE NEXT FEW
DAYS, ESPECIALLY FOR SOUTHERN AND CENTRAL PORTIONS OF THE U.S, AS
AN ACTIVE PATTERN PERSISTS. A FRONTAL BOUNDARY IS FORECAST TO
LINGER FROM THE SOUTHERN PLAINS TO THE MID-MISSISSIPPI AND OHIO
VALLEYS AS MULTIPLE WAVES OF LOW PRESSURE TRAVERSE THE BOUNDARY. A
DEEPENING UPPER-LEVEL LOW MOVING FROM THE ROCKIES INTO THE
SOUTHERN PLAINS WILL KEEP DEEP SOUTHERLY FLOW IN PLACE ACROSS THE
CENTRAL U.S., TRANSPORTING ABUNDANT MOISTURE NORTHWARD FOR
PRECIPITATION. HEAVY SNOW IS POSSIBLE FOR SOME AREAS IN THE
CENTRAL AND NORTHERN ROCKIES AS WELL AS THE ADJACENT HIGH PLAINS.
AS COLDER AIR SPREADS SOUTH ON SATURDAY, RAIN IS EXPECTED TO
CHANGE TO SNOW ACROSS THE SOUTHERN ROCKIES AS WELL AS PORTIONS OF
THE SOUTHERN HIGH PLAINS, WITH HEAVY SNOW ONCE AGAIN POSSIBLE FOR
SOME AREAS.

A VAST AREA, SPANNING FROM THE SOUTHERN/CENTRAL PLAINS THROUGH THE
MIDWEST/MISSISSIPPI VALLEY AND INTO PORTIONS OF TENNESSEE AND OHIO
VALLEYS, IS FORECAST TO HAVE NUMEROUS SHOWERS AND THUNDERSTORMS.
THE STORM PREDICTION CENTER HAS ISSUED SLIGHT AND ENHANCED RISKS
FOR SEVERE THUNDERSTORMS THIS AFTERNOON THROUGH EARLY SUNDAY
MORNING. REFER TO SPC`S WEBPAGE FOR FURTHER DETAILS ON THE SEVERE
WEATHER THREAT. ADDITIONALLY, EMBEDDED HEAVY RAINFALL WILL LIKELY
IMPACT THE SAME REGION THROUGH THE WEEKEND. AREAL AVERAGES OF 2 TO
5 INCHES ARE FORECAST ACROSS THE CENTRAL U.S. ISOLATED AREAS MAY
EXCEED 7 INCHES. RAPID RUNOFF OF EXCESSIVE RAIN CAN LEAD TO FLASH
FLOODING, AS WELL AS, RIVER FLOODING. THIS REGION HAS ALREADY
RECEIVED AROUND 400% OR MORE OF NORMAL MOISTURE IN THE LAST WEEK
AND WILL BE HIGHLY SENSITIVE TO ADDITIONAL RAINFALL.

IN GENERAL, MUCH OF THE EAST WILL RELATIVELY DRY AS HIGH PRESSURE
REMAINS IN PLACE AT THE MID AND UPPER LEVELS OF THE ATMOSPHERE. IN
TURN, TEMPERATURES WILL AVERAGE 10 TO 20 DEGREES WARMER FOR LATE
APRIL FOR SOME LOCATIONS.
SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE FOR PORTIONS
OF THE MID-ATLANTIC REGION SATURDAY AFTERNOON INTO SUNDAY AS A
COLD FRONT APPROACHES.

CAMPBELL/RYAN


GRAPHICS AVAILABLE AT WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_WBG.PHP

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