Area Forecast Discussion
Issued by NWS Des Moines, IA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

000
FXUS63 KDMX 161734
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
1234 PM CDT WED APR 16 2014

.UPDATE...
ISSUED AT 933 AM CDT WED APR 16 2014

EXPANDED BOTH THE WIND ADVISORY AND RED FLAG WARNING INTO THE
HIGHWAY 30 CORRIDOR AFTER WATCHING OBS TRENDS AND CHECKING NEW
FORECAST SOUNDINGS.

&&

.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...16/18Z
ISSUED AT 1234 PM CDT WED APR 16 2014

STRONG SSW WINDS WILL PERSIST THROUGH THIS AFTN...RESULTING IN
CROSSWINDS OF 20 TO 25 KT OR GREATER AT TIMES ON E-W RUNWAYS.
MEANWHILE A COLD FRONT WILL APPROACH FROM THE NW...MOVING ACROSS
THE AREA THIS EVE AND EARLY TONIGHT WITH WINDS GRADUALLY
DIMINISHING THEN SWINGING AROUND TO NW. LOW CLOUDS WILL ACCOMPANY
THE FRONT...WITH MVFR CIGS AND BRIEF -RA POSSIBLE ESP AT
KFOD/KMCW/KALO. AFTER ABT 14Z THURS EXPECT CLEARING SKIES AND VFR
CONDITIONS.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 6 PM CDT THIS EVENING FOR ADAIR-ADAMS-
APPANOOSE-AUDUBON-BOONE-CARROLL-CASS-CLARKE-CRAWFORD-DALLAS-
DAVIS-DECATUR-GREENE-GUTHRIE-JASPER-LUCAS-MADISON-MAHASKA-MARION-
MARSHALL-MONROE-POLK-POWESHIEK-RINGGOLD-STORY-TAMA-TAYLOR-UNION-
WAPELLO-WARREN-WAYNE.

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

WIND ADVISORY UNTIL 6 PM CDT THIS EVENING FOR ADAIR-ADAMS-
AUDUBON-CARROLL-CASS-CLARKE-CRAWFORD-DALLAS-DECATUR-GREENE-
GUTHRIE-LUCAS-MADISON-RINGGOLD-TAYLOR-UNION-WARREN-WAYNE.

&&

$$

UPDATE...LEE
SHORT TERM...FAB
LONG TERM...MS APR 14
AVIATION...LEE



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.