Area Forecast Discussion
Issued by NWS Des Moines, IA

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FXUS63 KDMX 160859
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
359 AM CDT WED APR 16 2014

.SYNOPSIS...
ISSUED AT 325 AM CDT WED APR 16 2014

LOW PRESSURE OVER SOUTHERN SD WILL MOVE TO NRN IA THIS EVENING AND
TO EASTERN LAKE SUPERIOR BY LATE THU. HIGH PRESSURE WILL BUILD
INTO THE AREA FRIDAY AND FRIDAY NIGHT. THE NEXT WEATHER SYSTEM
WILL MOVE THROUGH THE UPPER MIDWEST SATURDAY THROUGH SUNDAY.

&&

.SHORT TERM /TODAY/...
ISSUED AT 325 AM CDT WED APR 16 2014

THERE IS A LOT TO CONSIDER TODAY.  AS PREVIOUSLY DISCUSSED A SURFACE
LOW IS DEVELOPING OVER SOUTH DAKOTA AND A WARM FRONT WILL EXTEND
FROM THE LOW ACROSS NORTHERN IOWA/SOUTHERN MO.  SOUNDING ARE SHOWING
STRONG WARM AIR ADVECTION WITH THIS AND I BELIEVE THE MODELS ARE
UNDER-DOING THE WINDS.  WE ARE ALREADY SEEING REPORTED OF 20G30 MPH
OUT WEST AND AS THE LOW MOVES ACROSS TODAY...AIDED BY A DECENT SHORT
WAVE WINDS WILL INCREASE.  I HAVE TWEAKED WINDS AS MUCH AS I COULD
WHILE STILL STAYING IN COLLABORATION WITH NEIGHBORS AND CLOUD COVER
TODAY WILL DEFINITELY HAMPER MIXING...AT LEAST A LITTLE BUT IF WE
GET MORE SUN THERE WILL BE BETTER MIXING AND THE WIND ADVISORY I
CURRENTLY HAVE FOR SOUTHERN IOWA MAY NEED TO BE EXPANDED NORTHWARD.
GIVEN THE STRONG WARM ADVECTION I ALSO NUDGED HIGHS ABOVE GUIDANCE.
WINDS WILL DROP BELOW CRITERIA AROUND 00Z SO I HAVE ENDED THE WIND
ADVISORY AROUND THAT TIME.  WHILE THERE IS SOME FORCING WITH THIS
SYSTEM MOST OF IT STAYS NORTH.  POPS WERE TRIMMED SOUTH AS A RESULT.
ACROSS THE NORTH THE BEST CHANCE FOR PRECIP COME AS THE SHORTWAVE
SHIFTS ACROSS THE AREA...DURING THE AFTERNOON HOURS AND MAINLY NORTH
OF HIGHWAY 20.  QPF SHOULD BE LIGHT SO NOT EXPECTING ISSUES WITH
RAINFALL.

.LONG TERM /TONIGHT THROUGH TUESDAY/...
ISSUED AT 325 AM CDT WED APR 16 2014

MOISTURE BEING QUITE LIMITED WILL ALSO LIMIT THE PRECIP AS THE
ATTENDANT COLD FRONT FROM THE LOW IN NRN IA TONIGHT MOVES THROUGH.
SOME LIGHT SHOWER ACTIVITY IS POSSIBLE...MAINLY FAR NORTH. MIXING
WITH SNOW IS POSSIBLE OVER THE FAR NORTHWEST PART OF THE CWA.
CLEARING WILL SPREAD OVER THE AREA THU WITH HIGH PRESSURE BUILDING
INTO THE STATE.

STRONG WAA WILL TAKE PLACE FRI AND FRI NIGHT. IN SPITE OF DECENT
THETA-E ADVECTION...MOISTURE WILL ONCE AGAIN BE LIMITED DURING
THIS PHASE OF THE SYSTEM WARM FRONT WILL LIFT NORTH ON SAT. BY
LATER SAT NIGHT AND SUNDAY...ENOUGH MOISTURE WILL WORK INTO THE
SYSTEM FOR SHOWERS AND ISOLATED THUNDERSTORMS TO DEVELOP. A
DECENT S/WV IN THE SRN STREAM WILL MOVE INTO THE CENTRAL U.S. ON
EASTER SUNDAY. THIS WILL LIKELY PRODUCE WIDESPREAD SHOWER ACTIVITY
THROUGH THE DAY. SOME DISCREPANCY IN THE MODELS WITH THE ECMWF
MUCH SLOWER IN MOVING THE PRECIP OUT. WILL LEAN TOWARD A
COMPROMISE BLEND FOR NOW AND AWAIT ALL OF THE ENSEMBLES AND NEXT
RUN TO DETERMINE THAT BETTER. WARMER WEATHER WILL MOVE IN AS WE
MOVE INTO NEXT WEEK WITH THE NEXT WEATHER PRODUCER BEYOND THE DAY
SEVEN TIME FRAME.

&&

.AVIATION...16/06Z
ISSUED AT 1202 AM CDT WED APR 16 2014

SOME LOW VFR AND MID CLOUDS ACROSS THE CWA...WITH CLOUD COVER TO
INCREASE THROUGH THE NIGHT. SOUTHEASTERLY TO SOUTHERLY WINDS TO
INCREASE THROUGH THE NIGHT AND PICK UP EVEN MORE DURING THE DAY
WEDNESDAY WITH BREEZY TO WINDY CONDITIONS EXPECTED. COLD FRONT TO
PASS THROUGH THE CWA ALLOWING WINDS TO SHIFT TO THE SOUTHWEST AND
THEN NORTHWEST THROUGH THE PERIOD.


&&

.DMX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON TODAY TO 6 PM CDT THIS EVENING FOR
ADAIR-ADAMS-APPANOOSE-AUDUBON-CASS-CLARKE-DALLAS-DAVIS-DECATUR-
GUTHRIE-JASPER-LUCAS-MADISON-MAHASKA-MARION-MONROE-POLK-
POWESHIEK-RINGGOLD-TAYLOR-UNION-WAPELLO-WARREN-WAYNE.

WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM CDT THIS EVENING
FOR ADAIR-ADAMS-AUDUBON-CASS-CLARKE-DALLAS-DECATUR-GUTHRIE-LUCAS-
MADISON-RINGGOLD-TAYLOR-UNION-WARREN-WAYNE.

WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 6 PM CDT THIS EVENING
FOR APPANOOSE-BLACK HAWK-BOONE-DAVIS-GRUNDY-HAMILTON-HARDIN-
JASPER-MAHASKA-MARION-MARSHALL-MONROE-POLK-POWESHIEK-STORY-TAMA-
WAPELLO.

&&

$$

SYNOPSIS...MS APR 14
SHORT TERM...FAB
LONG TERM...MS APR 14
AVIATION...BEERENDS



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