Quantitative Precipitation Forecast
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925
FOUS30 KWBC 250800
QPFERD

EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
357 AM EDT MON JUL 25 2016

...VALID 12Z MON JUL 25 2016 - 12Z TUE JUL 26 2016...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...


SOUTHERN HIGH PLAINS
~~~~~~~~~~~~~~~~~~~~
SOMEWHAT ANOMALOUS MOISTURE ACROSS THE REGION (1-2 SIGMAS ABOVE
THE MEAN FOR LATE JULY) ALONG WITH DAYTIME HEATING ARE EXPECTED TO
HELP FIRE AFTERNOON AND EVENING CONVECTION.  THUNDERSTORMS ROLLING
OUT OF NORTHEAST NM INTO THE TX PANHANDLE COULD BECOME
PROBLEMATIC.  LOW-LEVEL INFLOW INCREASES TO 25+ KTS WHILE
PRECIPITABLE WATER VALUES (ADJUSTED FOR SEA LEVEL >= 1.5") AND
CAPES/INSTABILITY (2000+ J/KG) REMAIN SUFFICIENT FOR BROADER SCALE
HEAVY RAIN ISSUES.  THE MESOSCALE GUIDANCE HAS A GOOD SIGNAL FOR
LOCAL AMOUNTS IN THE 3-5" RANGE.  RECENT CONVECTION OVERNIGHT IS
EXPECTED TO SOMEWHAT LOWER FLASH FLOOD GUIDANCE VALUES/PARTIALLY
SATURATE SOILS.  THE LIMITING FACTOR FOR A BROAD SCALE THREAT IS
THE QUICK VEERING AND THEN WEAKENING OF THE LOW-LEVEL INFLOW SEEN
IN THE GUIDANCE BY THE END OF THE PERIOD -- TUESDAY 12Z.  THE 00Z
ECMWF THREW A MONKEY WRENCH IN THE SITUATION BY NOT HAVING THIS
POTENTIAL THUNDERSTORM COMPLEX, INCREASING UNCERTAINTY.  THOUGHT
IT PRUDENT TO HAVE A SEE TEXT/MARGINAL AREA FOR NORTHEAST NM AS
WELL AS THE TX/OK PANHANDLES AND POSSIBLY WESTERN OK.


NEW ENGLAND
~~~~~~~~~~~
THUNDERSTORMS ARE EXPECTED NEAR AND AHEAD OF A PROGRESSIVE COLD
FRONT.  SHOWERS AND THUNDERSTORMS ACROSS SOUTHEAST ONTARIO ARE
SLATED TO MOVE EASTWARD INTO NY WITH NEW ACTIVITY FORMING PORTIONS
OF NEW ENGLAND WITH TIME.  MOISTURE ANOMALIES ARE AROUND TWO
SIGMAS ABOVE THE MEAN FOR LATE JULY ACROSS NEW ENGLAND.  COMBINE
THIS WITH NEARLY UNIDIRECTIONAL WESTERLY FLOW AND DAYTIME HEATING
WHICH SHOULD PUSH CAPES INTO THE 1500-2000 J/KG RANGE, SHORT BOUTS
OF CELL TRAINING ARE POSSIBLE WITH HOURLY RAIN RATES UP TO 2".
THE MESOSCALE GUIDANCE ADVERTISES LOCAL AMOUNTS IN THE 2-4" RANGE,
MAINLY ACROSS NORTHERN AND SOUTHERN NEW ENGLAND.  CONSIDERING MORE
FAVORABLE THAN UNFAVORABLE FACTORS FOR HEAVY RAINFALL HERE,
FIGURED A SEE TEXT/MARGINAL AREA WAS THE BEST COURSE OF ACTION.

ROTH
$$





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