FXUS63 KOAX 010820
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
320 AM CDT FRI JUL 1 2011
.DISCUSSION...
MAIN FORECAST CONCERNS ARE HIGH TEMPERATURES TODAY AND THUNDERSTORM
CHANCES THE NEXT FEW DAYS.
THE UPPER AIR CHARTS FROM 00Z LAST EVENING SHOWED THE FOLLOWING. AT
850 MB...A WEDGE OF VERY WARM AIR (TEMPERATURES GREATER THAN 30 C)
EXTENDED FROM THE DESERT SOUTHWEST INTO WESTERN KANSAS. THIS BUBBLE
OF WARM AIR ALOFT WAS ALSO PRESENT AT 700 MB. AT 500 MB...A VIGOROUS
AND COMPACT CLOSED LOW WAS OVER WESTERN COLORADO. THE TEMPERATURE
AT 500 MB OVER GRAND JUNCTION WAS -14 C AND A 12 HOUR HEIGHT FALL OF
60 METERS WAS NOTED. WATER VAPOR LOOP SHOWED THAT THIS FEATURE HAD
MOVED TO NORTHERN COLORADO AS OF 08 UTC. IT SHOULD CONTINUE TO LIFT
NORTHEAST INTO WESTERN MINNESOTA BY THIS EVENING. SURFACE ANALYSIS
AT 08Z WAS A BIT MESSY...DUE TO THE OUTFLOW FROM EARLIER STORMS
ACROSS WESTERN AND NORTHERN NEBRASKA INTO SOUTH DAKOTA. WINDS HAD
SHIFTED TO THE NORTHWEST IN PARTS OF NORTHEAST NEBRASKA FROM THE
OUTFLOW BUT SYNOPTIC SCALE FRONT APPEARED TO BE FARTHER WEST. THIS
FRONT WILL PUSH INTO OUR FORECAST AREA...BUT VERY WARM OR HOT
CONDITIONS ARE EXPECTED AGAIN TODAY AHEAD OF THE FRONT. AT THIS
POINT...IT APPEARS THAT DEWPOINTS WILL BE LOW ENOUGH TO NOT ISSUE A
HEAT ADVISORY. MAIN THUNDERSTORM CHANCES THROUGH MID AFTERNOON
SHOULD BE ALONG OR BEHIND THE COLD FRONT. STORMS LATE THIS AFTERNOON
COULD DEVELOP ALONG OR AHEAD OF THE FRONT AS THE CAP WEAKENS. WILL
MENTION POTENTIAL FOR SEVERE STORMS MAINLY LATE AFTERNOON AND EARLY
EVENING. SHEAR AND INSTABILITY SEEM ADEQUATE FOR AT LEAST A FEW
SUPERCELLS.
TONIGHT...THE COLD FRONT SHOULD PUSH SOUTHWARD INTO MISSOURI AND
KANSAS WHERE IT WILL STALL. CURRENTLY HAVE PRECIPITATION CHANCES
LESS THAN 20 PERCENT FOR SATURDAY...AND TEMPERATURES WILL BE COOLER.
PRECIPITATION CHANCES WILL INCREASE BY SATURDAY NIGHT AS SOUTHERLY
LOW LEVEL WINDS RETURN AND MOISTURE IS LIFTED UP OVER THE FRONT.
THIS APPEARS TO BE A SETUP WHERE LOCALLY HEAVY RAIN AMOUNTS MAY
OCCUR SATURDAY NIGHT INTO SUNDAY MORNING. INCREASED THUNDERSTORM
CHANCES TO AROUND 50 PERCENT AFTER 06Z SATURDAY NIGHT AND KEPT
CHANCES 30-40 PERCENT THROUGH SUNDAY MORNING. HIGHS SUNDAY SHOULD
REACH 85 TO 90 F...THEN 90-95 F MONDAY.
MADE ONLY MINOR CHANGES TO THE FORECAST BEYOND MONDAY.
&&
.AVIATION...
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
WINDS WILL BE THE INITIAL CONCERN...THEN SCATTERED THUNDERSTORMS
ALONG AND BEHIND A COLD FRONT THIS AFTERNOON AND TONIGHT.
KOFK IS BEING AFFECTED BY OUTFLOW FROM THUNDERSTORMS EARLY...BUT
SHOULD SETTLE BACK TO THE SOUTHWEST AHEAD OF A COLD FRONT. LOW
LEVEL WIND SHEAR FROM THE SOUTHWEST AT 45 TO 55 KT IS EXPECTED AT
ALL THREE SITES THROUGH 13-15Z. THIS MORNING SURFACE WINDS FROM
THE SOUTH OR SOUTHWEST SHOULD BE AROUND 10 TO 14 KTS AND INCREASE
TO 14 TO 20 KT WITH GUSTS 20 TO 25 KTS. THE COLD FRONT TAKES A
WHILE TO PUSH THRU. AT OFK THE WINDS WILL SWITCH AROUND TO THE
NORTHWEST BETWEEN 18-21Z AND AT KOMA/KLNK AROUND 00-02Z. WHEN THE
WINDS DO COME AROUND THEY SHOULD INCREAST TO 10 TO 20 KTS.
THUNDERSTORMS...SOME STRONG TO SEVERE ARE EXPECTED TO DEVELOP
ALONG AND BEHIND THE FRONT. SOME OF THESE STORM MAY PRODUCE HIGH
WIND GUSTS. CIGS SHOULD MAINLY BE VFR...HOWEVER MVFR/IFR CIGS MAY
AFFECT THE SITES WHEN THUNDERSTORMS ARE PASSING THRU.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
DISCUSSION...MILLER
AVIATION...ZAPOTOCNY