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000
FXUS63 KDMX 282123
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
323 PM CST WED JAN 28 2015

.SHORT TERM /TONIGHT/...
ISSUED AT 323 PM CST WED JAN 28 2015

LOW PRESSURE OVER EASTERN NEBRASKA WILL MOVE EAST AND PASS EAST
OF THE CWA BY LATER TONIGHT. STRONG NWLY WINDS WILL OVERSPREAD THE
STATE TONIGHT AS THE ISALLOBARIC COUPLET MOVES THROUGH. WILL
BEGIN WITH A WIND ADVISORY OVER THE WEST PART OF THE CWA AROUND
06Z...WITH IT REACHING THE EASTERN PART BEFORE 11Z. PRECIP WILL BE
LIMITED WITH LIMITED MOISTURE...BUT TO EXPECT SOME LIGHT PRECIP
OVER THE NORTHEAST...WITH PATCHY DRIZZLE OVER THE CENTRAL
COUNTIES. FEEL THE DRIZZLE THREAT WILL END BEFORE THE SUB-
FREEZING TEMPS GET INTO THE CENTRAL COUNTIES AND DID NOT PLAY WITH
ANY FREEZING PRECIP OTHER THAN THE NORTHEAST. EVEN SO...DO NOT
EXPECT THERE TO BE ENOUGH TO CAUSE MAJOR ISSUES.

.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 323 PM CST WED JAN 28 2015

MODEL SOUNDINGS CONTINUE TO INDICATE LOW END ADVISORY GUST
POTENTIAL THROUGH MID MORNING THURSDAY WITH 42-48KTS AT TOP OF
MIXED LAYER IN FORECAST SOUNDINGS IN MUCH OF CENTRAL IOWA.
HOWEVER...THE BIGGEST PUSH OF COLD AIR AND STRONGEST WINDS OFF THE
SURFACE WILL OCCUR NEAR 12Z WITH WINDS WEAKENING SLOWLY THROUGH
THE DAY. WITH THE POTENTIAL GUSTS LOWERING THROUGH THE MORNING AND
A GRADUAL DECLINE IN SUSTAINED WINDS...WILL LET THE ADVISORY GO AT
15Z. CLOUDS ALSO LOOK TO REMAIN IN PLACE FOR MUCH OF THE MORNING
ALTHOUGH DRYING IN THE SOUNDINGS OCCURS BY AFTERNOON WITH SOME
PARTLY SUNNY CONDITIONS AFTER MIDDAY IN MANY LOCATIONS.

FOCUS REALLY THEN SHIFTS TO THE WEEKEND SYSTEM AND ASSOCIATED
PRECIPITATION POTENTIAL. 00Z/06Z MODEL RUNS WERE EXTREMELY BULLISH
WITH THIS SYSTEM IN REGARDS TO HEAVY PRECIPITATION THIS WEEKEND.
THE CONCERN WITH THIS SYSTEM IS THE STRENGTH OF THE NORTHERN
SYSTEM AND THE PHASING WITH LARGE UPPER LOW IN THE SOUTHWESTERN
UNITED STATES. THE OLDER RUNS WERE STRONGER WITH THIS NORTHERN
SYSTEM AND WITH THE SUBSEQUENT PHASING AS WELL. THIS PULLED MUCH
MORE MOISTURE NORTHWARD ALONG AND INVERTED TROF AND PRODUCED A
LARGE AMOUNT OF SNOWFALL ACROSS IOWA.  IN CONTRAST...THE CURRENT
12Z RUNS HAVE A QUICKER NORTHERN WAVE WITH LITTLE PHASING AND
SUBSEQUENTLY A MUCH DRIER SOLUTION IN IOWA. THERE STILL EXISTS A
LARGE SPREAD IN GFS ENSEMBLE MEMBERS AND THEREFORE UNCERTAINTY
REMAINS HIGH. HAVE CUT BACK ON POPS SUBSTANTIALLY DURING THE DAY
SATURDAY AND KEPT THE HIGHEST POPS IN THE SOUTH AND EAST ON
SATURDAY NIGHT INTO SUNDAY. AT THIS POINT...LIGHT ACCUMULATIONS
ARE ANTICIPATED BEFORE THE SNOW ENDS ON SUNDAY. THEREAFTER...MUCH
COLDER AIR OVERSPREAD THE STATE WITH READINGS BELOW NORMAL INTO
NEXT WEEK. THERE WILL ALSO BE LOW CHANCES FOR POPS RETURNING FROM
TIME TO TIME AS WEAK SYSTEM PASS THROUGH THE FAST NORTHWEST FLOW.

&&

.AVIATION...28/18Z
ISSUED AT 1125 AM CST WED JAN 28 2015

LOW PRESSURE OVER NORTH CENTRAL KS WILL MOVE ACROSS IA THIS
EVENING. LOW CLOUDS WILL HOLD IN THE KMCW AREA AND KFOD AREAS...WITH
VFR ELSEWHERE. AS LOW PASSES EAST...MVFR CIGS WILL MOVE SOUTH WITH
STRONG NWLY WINDS

OUTLOOK...STRONG NWLY WINS WILL CONTINUE THURSDAY AFTERNOON WITH
CIGS RISING TO VFR AND THEN CLEARING. VFR CONDITIONS EXPECTED
WITH HIGH PRESSURE FRIDAY INTO SAT. A WEATHER SYSTEM OVER THE
WEEKEND IS LIKELY TO AFFECT MOST OF NOT ALL THE TAF SITES WITH
STRATUS AND SNOW.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...WIND ADVISORY FROM 4 AM TO 9 AM
CST THURSDAY FOR BUTLER-CERRO GORDO-CLARKE-DECATUR-FRANKLIN-GRUNDY-
HARDIN-JASPER-LUCAS-MADISON-MARION-MARSHALL-POLK-RINGGOLD-STORY-
UNION-WARREN-WORTH.

WIND ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST THURSDAY FOR ADAIR-
ADAMS-AUDUBON-BOONE-CALHOUN-CARROLL-CASS-CRAWFORD-DALLAS-EMMET-
GREENE-GUTHRIE-HAMILTON-HANCOCK-HUMBOLDT-KOSSUTH-PALO ALTO-
POCAHONTAS-SAC-TAYLOR-WEBSTER-WINNEBAGO-WRIGHT.

&&

$$

SHORT TERM...MS
LONG TERM...COGIL
AVIATION...MS JAN 15