Prognostic Meteorological Discussion
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FXUS02 KWBC 310526
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
125 AM EDT THU JUL 31 2014

VALID 12Z SUN AUG 03 2014 - 12Z THU AUG 07 2014

...OVERVIEW AND GUIDANCE PREFERENCES...

THE WELL-FORECAST AMPLIFIED PATTERN WILL SOON COME TO AN END OVER
THE CONUS... BUT THE RIDGING WILL STAY IN THE PAC NW WHILE
TROUGHING SHOULD LINGER OVER THE CENTRAL/EASTERN STATES. THE
GUIDANCE AND ENSEMBLES HAVE BEEN SHOWING THIS FOR SEVERAL
CYCLES... BUT THE SPECIFICS... AND HOW WE GET THERE... ARE FUZZY.
FIRST PART OF THE PERIOD... SUN-TUE... WILL FEATURE THE LINGERING
BOUNDARY ALONG THE GULF AND EAST COASTS WHILE NORTHERN STREAM
ENERGY PUSHES THROUGH ONTARIO AND QUEBEC... PUSHING A COLD FRONT
SOUTHWARD AND EASTWARD THROUGH THE PLAINS AND OH VALLEY INTO THE
NORTHEAST. HEIGHTS SHOULD GRADUALLY LOWER OVER THE SW STATES AND
CENTRAL/SOUTHERN PLAINS AS INITIALLY WEAK ENERGY MEANDERS OUT OF
SW CANADA BEFORE DROPPING SOUTHEASTWARD INTO THE UPPER MIDWEST AND
GREAT LAKES REGION. THE ECMWF CONTINUES TO BE MORE AGGRESSIVE WITH
DEVELOPING THIS VORT MAX INTO SOMETHING MORE ORGANIZED/CLOSED OFF
IN VARIOUS RUNS WHILE THE GFS HAS BEEN WEAKER AND MORE
PROGRESSIVE. THE CANADIAN MAY WANT TO HAVE IT BOTH WAYS -- A BIT
STRONGER BUT STILL PROGRESSIVE. THE ENSEMBLES SHOW ANYTHING AND
EVERYTHING IN BETWEEN THE GFS/ECMWF... AND BEYOND... SO HAVE OPTED
TO SPLIT THAT DIFFERENCE FOR NOW.


...SENSIBLE WEATHER HIGHLIGHTS...

THE RECORD WARM/COLD OF THE PAST COUPLE OF WEEKS SHOULD SUBSIDE AS
THE PROJECTED TEMPERATURE ANOMALIES SHOULD BE IN THE +/- 5-12F
RANGE RATHER THAN THE 15-25F RANGE. AREAS ALONG AND EAST OF THE
ROCKIES SHOULD BE NEAR TO BELOW AVERAGE WHILE THE PAC NW STAYS A
BIT ABOVE AVERAGE. PRECIPITATION SHOULD FOCUS ALONG THE STALLED
FRONTAL BOUNDARY EARLY IN THE PERIOD BEFORE IT DISSIPATES.
MONSOONAL MOISTURE SHOULD BE LESS PLENTIFUL BY MIDWEEK AS THE
RIDGE WEAKENS AND SHIFTS OUT OF THE FOUR CORNERS AND INTO NW
MEXICO. TO THE NORTH... THERE SHOULD BE SOME PRECIP WITH THE
HEIGHT FALLS IN THE CENTRAL/NORTHERN PLAINS INTO THE UPPER MIDWEST
WED-THU... BUT AMOUNTS AND ORIENTATION ARE CONTINGENT ON THE YET
UNKNOWN SPEED/AMPLITUDE OF THE SHORTWAVE AND ANY SFC REFLECTION.


FRACASSO

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