Area Forecast Discussion
Issued by NWS Des Moines, IA

Current Version | Previous Version | Graphics & Text | 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 45 46 47 48 49 50

000
FXUS63 KDMX 151138
AFDDMX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
638 AM CDT WED APR 15 2015

.SHORT TERM /TODAY/...
ISSUED AT 352 AM CDT WED APR 15 2015

A LARGE SURFACE HIGH PRESSURE CENTER ENTRENCHED OVER THE GREAT LAKES
WILL DOMINATE THE REGION TODAY...EVEN AS A 500 MB SHORTWAVE
APPROACHES FROM THE SOUTHWEST. THE BROAD BUT MODEST ASCENT REGION
ASSOCIATED WITH THE APPROACHING WAVE HAS BEEN GENERATING LIGHT
SHOWERS ACROSS NORTHERN MISSOURI OVERNIGHT...BUT THESE HAVE SO FAR
STRUGGLED TO REACH OUR FORECAST AREA DUE TO THE LOW LEVEL DRY AIR
FLOWING OUT OF THE SURFACE HIGH TO OUR EAST. RADAR TRENDS AND HIGH
RESOLUTION MODELS INDICATE THAT THESE SHOWERS WILL BE ABLE TO
PENETRATE OUR SOUTHERN AND SOUTHWESTERN AREAS EARLY THIS
MORNING...HOWEVER AS DAYTIME MIXING KICKS IN BY LATE MORNING THE DRY
AIR AND SUBSIDENCE SHOULD GAIN THE UPPER HAND RESULTING IN A GRADUAL
DISSIPATION OF THE SHOWERS. HAVE TRENDED POPS IN THIS
DIRECTION...WITH SOLID CHANCES EARLY THIS MORNING DECREASING TO
SLIGHT CHANCES BY THE AFTERNOON AND EVERYWHERE CONFINED TO THE SOUTH
AND SOUTHWEST. IN ANY EVENT...THE SHOWERS WILL BE OF MINIMAL IMPACT
AS THUNDER IS NOT EXPECTED AND RAINFALL WILL NOT AMOUNT TO MUCH. THE
RAIN AND ASSOCIATED CLOUDS WILL HOLD TEMPERATURES DOWN IN THE
SOUTHWEST AS WELL...BUT IN OUR NORTHERN AND EASTERN COUNTIES WE
SHOULD BE ABLE TO WARM INTO THE MID TO UPPER 60S DESPITE CIRRUS
CLOUDS OVERHEAD. RELATIVE HUMIDITY WILL DROP INTO THE 20 TO 25 MPH
RANGE IN OUR NORTHEAST THIS AFTERNOON BUT EXPECTED WINDS OF 15 TO 20
MPH ARE INSUFFICIENT FOR A FIRE WEATHER HEADLINE AT THIS TIME.

.LONG TERM /TONIGHT THROUGH TUESDAY/...
ISSUED AT 352 AM CDT WED APR 15 2015

A VIGOROUS UPPER LEVEL SYSTEM OVER UTAH EARLY THIS MORNING IS
CLOSING OFF...WILL DIG SOUTH INTO ARIZONA AND NEW MEXICO TONIGHT
AND THURSDAY. AS EXPECTED THE PREVIOUS NIGHT...THE SOLUTIONS ARE
TRENDING TOWARD THE SLOWER AND MORE PERSISTENT ECMWF/GEM SOLUTIONS
THROUGH INTO THE WEEKEND. AN ISOLATED LIGHT SHOWER OR TWO MAY
LINGER INTO THE EVENING OTHERWISE THE AREA IS EXPECTED TO REMAIN
DRY. THE SHIFT OF THE UPPER LOW SOUTH INTO THURSDAY WILL HELP
PRODUCE A DEFAULT WEAK UPPER RIDGE INTO IOWA INTO FRIDAY. A FEW
FRAGMENTS OF ENERGY ARE EXPECTED TO BREAK OFF THE UPPER LOW AND
LIFT INTO THE MIDWEST INTO FRIDAY. A FEW SHOWERS AND ISOLATED
THUNDERSTORMS WILL BE POSSIBLE MAINLY OVER THE FAR WEST TO
SOUTHWEST BOTH DAY WITH MOST LOCATIONS REMAINING DRY WITH BROAD
SFC HIGH PRESSURE IN PLACE OVER MUCH OF THE NORTHERN PLAINS AND
GREAT LAKES REGION.. THE PRIMARY FOCUS FOR PRECIPITATION DURING
THIS PERIOD WILL BE TO THE WEST IN NEBRASKA WHERE BETTER UPPER
LEVEL DIFFLUENCE WILL BE LOCATED. THE BEST CHANCE FOR
PRECIPITATION THROUGH THE PERIOD REMAINS SATURDAY NIGHT THROUGH
SUNDAY NIGHT AS THE UPPER LEVEL SYSTEM LIFTS NORTHEAST AND INTO
THE REGION. CERTAINLY WILL HAVE THE POTENTIAL FOR THUNDERSTORMS
THOUGH THE OVERALL DYNAMICS AND THERMAL PROFILES DO NOT LOOK
FAVORABLE FOR SEVERE WEATHER.

ANOTHER UPPER LOW SYSTEM WILL DROP INTO THE NORTHERN PLAINS EARLY
NEXT WEEK AND WILL BECOME THE DOMINANT WEATHER FEATURE FOR THE
REMAINDER OF THE EXTENDED. THE SYSTEM WILL BRING A TRANSITION TO
BROAD CYCLONIC FLOW AND COOLER WEATHER TO THE STATE.

&&

.AVIATION...15/12Z
ISSUED AT 638 AM CDT WED APR 15 2015

VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. A FEW LIGHT
SHOWERS ARE POSSIBLE AT DSM AND OTM THIS MORNING...BUT PROBABILITY
IS LOW AND ANY IMPACTS WOULD BE NEGLIGIBLE SO HAVE NOT INCLUDED IN
THE 12Z TAFS. ESE WINDS WILL PICK UP LATER THIS MORNING WITH SOME
GUSTS BY AFTERNOON...THEN DROP OFF AGAIN WITH SUNSET TONIGHT.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...LEE
LONG TERM...DONAVON
AVIATION...LEE



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