FXUS63 KOAX 200808
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
308 AM CDT WED JUL 20 2011
.DISCUSSION...
UPPER RIDGE THAT HAS BEEN IN PLACE OVER THE CENTRAL PART OF THE
COUNTRY THE PAST FEW DAYS FLATTENS ACROSS THE NORTHERN PLAINS
TODAY AS SHARP TROUGH OVER THE NORTHERN ROCKIES THIS MORNING
TRACKS TOWARD SOUTH CENTARL CANADA.
LATEST MODELS CONTINUE TO DROP A WEAK COLD FRONT INTO EASTERN
NEBRASKA BY LATE THIS AFTERNOON THEN STALL THE BOUNDARY NEAR THE
SOUTHEAST NEBRASKA BORDER TONIGHT AND THURSDAY. THIS BOUNDARY THEN
WASHES OUT THURSDAY NIGHT AS A SURFACE TROUGH DEVELOPS OVER THE
WESTERN HIGH PLAINS AHEAD OF THE NEXT UPPER TROUGH OVER THE
PACIFIC NORTHWEST. THIS BOUNDARY WILL MAKE FORECAST FOR THE AREA
SOMEWHAT UNCERTAIN DEPENDING ON ACTUAL LOCATION AND ITS ABILITY TO
FOCUS CONVECTION WITH A SHARP GRADIENT IN TEMPERATURE EXPECTED IN
ITS VICINITY.
PLAN AT THIS TIME TO LET CURRENT HEADLINE FOR HEAT END AT 00Z WITH
LATEST DATA SHOWING TEMPERATURES DROPPING BELOW CRITERIA TONIGHT AS
FRONT AND CONVECTION MOVE INTO THE AREA. HEAT ADVISORY MAY BE
NEEDED IN AREAS SOUTH OF THE FRONT ON THURSDAY AFTERNOON BUT SOME
UNCERTAINTY AT THIS TIME REGARDING ACTUAL POSITION OF THE FRONT
AND EXTENT AND IMPACT OF CONVECTION SO WILL WAIT AND SEE HOW
THINGS DEVELOP OVERNIGHT. CHANCE POPS CONTINUED FOR MOST OF THE
AREA TONIGHT THROUGH THURSDAY NIGHT. HOT TEMPERATURES RETURN ON
FRIDAY WITH WARM FRONT DEVELOPING NORTH OF THE AREA ACROSS SOUTH
DAKOTA AS THE NEXT UPPER WAVE HEADS TOWARD THE NORTHERN PLAINS AND
SOUTH CENTRAL CANADA.
EXTENDED PART OF THE FORECAST SOMEWHAT UNCERTAIN AT THIS TIME WITH
PATTERN REMAINING RATHER ACTIVE AS SERIES OF WAVES CONTINUE TO
TRACK ACROSS THE NORTHERN PLAINS AND HELP SUPPRESS RIDGING. NO
CHANGES AT THIS TIME WITH CHANCE OF MORE STORMS THIS WEEKEND AS
NEXT WEATHER SYSTEM TRACKS EAST ALONG THE CANADIAN BORDER EARLY
IN THE PERIOD BRINGING ANOTHER COLD FRONT INTO THE AREA SATURDAY
AND SATURDAY NIGHT THEN STALLING OUT NEAR THE SOUTHERN BORDER
AREA AGAIN ON SUNDAY.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
VFR CONDITIONS SHOULD GENERALLY PREVAIL THROUGH THE PERIOD. WEAK
COLD FRONT WILL APPROACH KOFK BY EARLY EVENING AND POSSIBLY REACH
THE KOMA AND KLNK AREA AFTER 06Z. THIS WILL BRING A WIND SHIFT.
SOME SCATTERED THUNDERSTORMS WILL BE POSSIBLE AFTER 00Z...BUT
PROBABILITIES ARE TOO LOW TO MENTION AT THIS TIME.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT THIS EVENING FOR NEZ011-
012-015>018-030>034-042>045-050>053-065>068-078-088>093.
IA...EXCESSIVE HEAT WARNING UNTIL 7 PM CDT THIS EVENING FOR IAZ043-
055-056-069-079-080-090-091.
&&
$$
FOBERT/MILLER