Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS63 KOAX 280444 AFDOAX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 1144 PM CDT FRI MAR 27 2015 .SHORT TERM...(TONIGHT THROUGH MONDAY) ISSUED AT 242 PM CDT FRI MAR 27 2015 ONE MORE SHOT AT RAIN/SNOW MIX OR SNOW TONIGHT...BEFORE MILDER WEATHER RETURNS FOR THE WEEKEND AND BEYOND. SUBJECTIVE 12Z UPPER AIR ANALYSIS INDICATES DIGGING UPPER-LEVEL TROUGH OVER THE EASTERN US...WITH 500MB HEIGHT FALLS FROM MI TO KS AND EASTWARD...AND AN UPPER-LEVEL RIDGE ACROSS THE WESTERN US...WITH 500MB HEIGHT RISES ALONG THE HIGH PLAINS. UPPER-LEVEL JET WAS STRONGEST AHEAD OF THE TROUGH...WITH UP TO 130KT WINDS IN THE MID-ATLANTIC...BUT WITH A 125KT JET STREAK NOSING FROM THE DAKOTAS INTO KS/CENTRAL OK. 850MB COLD POCKET CENTERED IN THE GREAT LAKES HAS BROUGHT SUB-0C TEMPERATURES FROM THE MO RIVER VALLEY/DAKOTAS THROUGH THE OHIO RIVER VALLEY AND EASTWARD. SURFACE RIDGE AXIS AT 19Z EXTENDED FROM WESTERN LAKE SUPERIOR THROUGH CENTRAL IA/NORTHWEST MO/CENTRAL OK...WITH SURFACE LOW IN NORTHWEST ND. WATER VAPOR IMAGERY INDICATED A WEAK SHORTWAVE TROUGH PUSHING SOUTHWARD OUT OF ND THROUGH WESTERN MN...AND AN AREA OF ASSOCIATED PRECIPITATION WAS NOTED IN EASTERN ND/EASTERN SD DIVING SOUTH-SOUTHEASTWARD. MAIN FORECAST CONCERNS ARE POTENTIAL FOR LIGHT PRECIPITATION TONIGHT...PRECIPITATION WITH A FRONTAL PASSAGE ON LATE SATURDAY NIGHT...AND WARMING EARLY NEXT WEEK. NARROW BAND OF LIFT WILL SKIRT MAINLY THE MO RIVER AND EASTWARD...WITH LIFT OVERCOMING DRY LOW LEVELS AROUND 00Z OR LATER AND SLIDING SOUTHEASTWARD THROUGH THE NIGHT. PRECIP AMOUNTS SHOULD REMAIN LIGHT...WITH UNDER A TENTH OF QPF AND JUST A COUPLE TENTHS OF SNOW IN WESTERN IOWA...TAPERING QUICKLY TO LITTLE OR NO PRECIPITATION ON THE NEBRASKA SIDE. IN WAKE OF THE SYSTEM...SHOULD SEE RETURN TO SOUTHEASTERLY SURFACE FLOW BY SATURDAY AFTERNOON...ALONG WITH MID-LEVEL WARM AIR ADVECTION BEGINNING...RESULTING IN MILDER TEMPERATURES THAN THE LAST FEW DAYS. NEXT SHORTWAVE TROUGH IN THE CYCLONIC FLOW IS PROGGED TO SLIDE THROUGH ON SATURDAY NIGHT...WITH A COLD FRONTAL PASSAGE BRINGING ANOTHER POTENTIAL FOR RAIN. THE WAVE/FRONT SEEM FAST-MOVING...AND THINK ANY PRECIPITATION WILL BE SHORT-LIVED AND WILL EXIT QUICKLY IN THE MORNING HOURS ON SUNDAY. HAVE SPED TIMING OF PRECIPITATION EXITING THE AREA ON SUNDAY...BUT DID INCREASE POPS ON LATE SATURDAY NIGHT. RETURN FLOW ONCE AGAIN COMMENCES SUNDAY NIGHT AS UPPER-LEVEL RIDGING OVERCOMES NORTHWESTERLY FLOW...WITH SURFACE AND MID-LEVEL SOUTHWESTERLY FLOW ON MONDAY. WITH POTENTIAL FOR STRONG MIXING...ALONG WITH FAIRLY DRY MID-LEVELS...COULD SEE RH ON THE LOW SIDE AND BREEZY WINDS ON MONDAY. WILL CONTINUE TO MONITOR CONDITIONS FOR ANY FIRE WEATHER POTENTIAL...BUT FOR NOW...THE COMBINATION WILL AT LEAST RESULT IN TEMPERATURES IN THE 70S. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 242 PM CDT FRI MAR 27 2015 SURFACE FLOW LIKELY WEAKENS ON TUESDAY COMPARED TO MONDAY AS A WEAK RIDGE AMBLES NEAR THE CWA...BUT TEMPERATURES SHOULD REMAIN MILD AS 850MB WARM AIR ADVECTION CONTINUES. 850MB MOISTURE SHOULD INCREASE ON TUESDAY NIGHT INTO WEDNESDAY AS FLOW TRAJECTORY TAKES MOISTURE UP FROM THE GULF OF MEXICO...AND A SHORTWAVE TROUGH IS PROGGED TO MOVE ACROSS THE NORTHERN PLAINS BY WEDNESDAY...DRAGGING A COLD FRONT THROUGH THE CENTRAL PLAINS WITH IT. AGREEMENT AMONG MODELS IS BETTER TODAY REGARDING BOTH TIMING AND MOISTURE RETURN...AND HAVE INCREASED POPS ON WEDNESDAY ASSOCIATED WITH FRONTAL PASSAGE. MODELS DO INDICATE SOME INSTABILITY IN THE AREA GIVEN MOISTENING AND WARM LOWER- TO MID-LEVELS...AND HAVE INCLUDED THUNDER MENTION. FORECAST BECOMES MUCH MORE UNCERTAIN BEHIND THE FRONT AS SOLUTIONS DIVERGE. GFS REMAINS DRY AND BRINGS IN COOLER AIR QUICKLY BEHIND THE FRONT...WHILE ECMWF IS SLOWER WITH DRAGGING COLD AIR DOWN AS IT MOVES A SOUTHERN STREAM LOW ACROSS THE SOUTHERN/CENTRAL PLAINS...WITH WIDESPREAD PRECIPITATION. KEPT A MODEL BLENDED PRECIPITATION IN THE FORECAST FOR THURSDAY NIGHT/FRIDAY...BUT HAVE VERY LOW CONFIDENCE IN ACTUAL PATTERN EVOLUTION EXCEPT THAT TEMPERATURES WILL TREND TOWARD AT LEAST SOMEWHAT COOLER READINGS. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1129 PM CDT FRI MAR 27 2015 VFR CONDITIONS ARE FORECAST THROUGH SATURDAY EVENING. CIGS BETWEEN FL050 AND FL120 WILL PERSIST INTO MID MORNING. THEN SCATTERED HIGH CLOUDS ARE EXPECTED. SOUTHEAST WINDS NEAR 10KT OVERNIGHT WILL INCREASE INTO THE 15 TO 25KT RANGE AROUND 18Z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...MAYES LONG TERM...MAYES AVIATION...DERGAN

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