FXUS63 KGID 010522

AFDGID



AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE HASTINGS 

1220 AM CDT SUN AUG 1 2010



.AVIATION...06Z TAF. VFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE 

PERIOD. THERE MAY BE BRIEF REDUCTION IN VISIBILITY DUE TO FOG 

BETWEEN 10Z AND 14Z. HIGH PRESSURE WILL CONTINUE TO DRIFT 

EAST...KEEPING WINDS FROM THE SOUTH. GRADIENT TIGHTENS A BIT THIS 

AFTERNOON...SO WILL SEE SOME GUSTS TO NEAR 20 KTS. OTHERWISE..MOSTLY 

CIRRUS/HIGH LEVEL CLOUDS THROUGH THE PERIOD. 



&&



.PREV DISCUSSION... /ISSUED 310 PM CDT SAT JUL 31 2010/ 



SHORT TERM...TONIGHT THROUGH SUNRISE MONDAY. MAIN CONCERN WILL BE 

TEMPERATURES ALONG WITH SMALL CHANCES FOR TSTMS ESPECIALLY SUNDAY 

NIGHT. 



SATELLITE WATER VAPOR IMAGERY...UPPER AIR ANALYSIS AND WIND PROFILER 

NETWORK SHOWING UPPER LOW HAS MOVED INTO THE PACIFIC NW COAST WITH 

JET ACROSS THE NORTHERN PLAINS AND THEN DIVING SOUTHEAST INTO THE 

OHIO RIVER VALLEY. WEAK RIDGING FROM THE ROCKIES TO THE CENTRAL 

PLAINS WITH SEVERAL SUBTLE SHORTWAVES MOVING THROUGH THE FLOW. 

SURFACE ANALYSIS HAS HIGH PRESSURE OVER OUR CWA...ODX TO GRI AT 18Z. 

SOME LOCATIONS HAVE MIXED OUT WITH DEWPOINTS IN THE LOWER 60S WHILE 

OTHER SPOTS STILL AROUND 70. TEMPERATURES RUNNING SIMILAR TO 

YESTERDAY AND EXPECT HIGHS TO RANGE FROM THE MID/UPPER 90S SOUTH TO 

THE LOW 90S NORTH. WEAK SURFACE BOUNDARY THAT MOVED THROUGH EARLY 

FRIDAY IS NOW LOCATED ACROSS NORTHERN OK. TSTMS HAD ALREADY 

DEVELOPED OVER EASTERN CO. 



AFTER LOOKING AT FORECAST SOUNDINGS...PROGGED 850 TEMPS...MOS 

GUIDANCE...ETC THINK SUNDAY WILL BE SLIGHTLY WARMER THAN TODAY. LOWS 

TONIGHT SHOULD BE NEAR 70 GIVE OR TAKE A COUPLE OF DEGREES AND THEN 

A DEGREE OR TWO WARMER SUNDAY NIGHT. 



TSTM CHANCES CONTINUE TO BE A CHALLENGE. CONVECTION BROKE EARLY THIS 

MORNING JUST TO THE SOUTH OF OUR CWA. WITH BOUNDARY A LITTLE FURTHER 

SOUTH THINK WE SHOULD REMAIN DRY BUT ONE CONCERN IS HOW FAR THE 

ACTIVITY IN EASTERN CO WILL PROGRESS OUR WAY. 4KM WRF SHOWS THIS 

REMAINING WELL TO OUR WEST WITH BETTER UPSLOPE.  BETTER CHANCES LOOK 

TO BE SUNDAY NIGHT AS CONVECTION FIRES TO THE NORTH FROM SDAK INTO 

NORTHERN NEB ALONG THE SURFACE TROUGH AND THEN WORKS ESE OVERNIGHT. 

WILL BOOST POPS INTO CHANCE CATEGORY IN THE NORTH AND THEN TAPER 

BACK ACROSS THE SOUTH. 



LONG TERM...12Z MONDAY THROUGH SATURDAY. THUNDERSTORM CHANCES POSE 

THE MAIN CHALLENGE THROUGH THE EXTENDED PERIOD. OTHER AREA OF FOCUS 

IS HOT/HUMID CONDITIONS MONDAY...LINGERING INTO TUESDAY ACROSS NORTH 

CENTRAL KS. 



OVERALL...A FAIRLY TYPICAL SUMMER PATTERN LOOKS TO MAINTAIN A GRIP 

ON THE AREA THROUGH THE EXTENDED PERIOD...AS MID/UPPER LEVEL

RIDGING CONTINUES TO DOMINATE THE SOUTHERN TWO THIRDS OF THE

CONUS. THE CWA WILL REMAIN TOWARD THE NORTHERN PERIPHERY OF THE

UPPER RIDGING...ENOUGH UNDER ITS GRASP TO KEEP TEMPERATURES NEAR

OR ABOVE AVERAGE...BUT ALSO STILL IN THE PATH OF MID/UPPER

DISTURBANCES AND POCKETS OF MONSOON MOISTURE PIVOTING AROUND THE

RIDGE TO KEEP THUNDERSTORM CHANCES IN PLAY. SOME OF THE MORE

INTERESTING WEATHER LOOKS TO COME EARLY IN THE PERIOD AS A

SHORTWAVE RIDING EAST ALONG THE US/CANADIAN BORDER WILL PUSH A

COLD FRONT SOUTH INTO THE AREA LATE MONDAY AFTERNOON OR MONDAY

EVENING. STILL SOME TIMING DIFFERENCES BETWEEN MODELS AS THE GFS

HOLDS THE FRONT BACK UNTIL EVENING WHILE THE NAM AND ECMWF BRING

IT IN DURING THE AFTERNOON. FORECAST FOLLOWS THE NAM/ECMWF QUICKER

ARRIVAL...INTRODUCING THUNDERSTORM CHANCES DURING THE AFTERNOON

ACCORDINGLY. AHEAD OF THE FRONT...IT WILL BE VERY HOT AND HUMID AS

SOUTH/SOUTHWEST WINDS ADVECT H85 TEMPS AROUND +30C INTO THE AREA.

SURFACE DEWPOINTS IN THE UPPER 60S TO MID 70S WILL COMBINE WITH

THE HOT AIRMASS TO MAKE FOR A MUGGY DAY. EXPECT HIGH TEMPS TO

RANGE FROM AROUND 90F IN THE NORTH BEHIND THE EARLIER FRONTAL

PASSAGE TO AROUND 103F IN THE SOUTHWEST...WITH HEAT INDICES

REACHING 100F OR HIGHER ACROSS THE SOUTHEAST HALF TO TWO THIRDS OF

THE CWA. NEEDLESS TO SAY GIVEN THIS WARM/HUMID AIRMASS...PLENTY OF

INSTABILITY WILL BE AVAILABLE FOR THE FRONT TO ACT ON. IN

FACT...0-1KM MLCAPES ARE PROGGED TO REACH OVER 3000 OR 3500 J/KG.

DEEP LAYER SHEAR IS WEAK AHEAD OF THE FRONT...BUT IS ACTUALLY

PRETTY DECENT AT 30-35 KTS ALONG AND BEHIND IT. THIS COMBINATION

OF SHEAR AND INSTABILITY WILL SUPPORT SOME RISK FOR SEVERE WEATHER

LATE MONDAY AFTERNOON INTO MONDAY EVENING...WHICH THE HWO AND SPC

DAY 3 OUTLOOK ALREADY HAVE WELL IN HAND. COULD ALSO SEE SOME

LOCALLY HEAVY RAINFALL AS PRECIPITABLE WATERS CLIMB TO AROUND 2

INCHES. THE NOCTURNAL LLJ NOSES INTO THE AREA MONDAY

EVENING...WHICH SHOULD ENHANCE THUNDERSTORM CHANCES...BEFORE

VEERING LATER MONDAY NIGHT AND TAKING BETTER CONVECTIVE CHANCES

EASTWARD WITH IT.



THE FRONT LOSES SOME OF ITS PUSH AND HANGS UP ACROSS OR NEAR THE 

SOUTHEAST CWA THROUGH MUCH OF THE DAY ON TUESDAY. FORCING IS NOT AS 

FOCUSED AS ON MONDAY WHEN THE FRONT WAS PUSHING THROUGH...HOWEVER 

PLENTY OF MOISTURE WILL STILL BE AROUND AS LIGHT NORTHEAST FLOW 

NORTH OF THE FRONT KEEPS RICH BOUNDARY LAYER MOISTURE POOLED OVER 

THE AREA...WHILE SOME MID/UPPER LEVEL MONSOON MOISTURE GETS ROTATED 

OVER THE AREA ON NORTHERN PERIPHERY OF MID/UPPER RIDGE. AVAILABLE 

MOISTURE/RESULTANT INSTABILITY...PROXIMITY OF BOUNDARY...AND WEAK 

SHORTWAVE RIPPLES LIKELY TRANSLATING THROUGH THE FLOW WILL BRING 

MORE THUNDERSTORM CHANCES TUESDAY INTO TUESDAY NIGHT...WITH 

CONVECTION LIFTING OUT OF THE HIGH PLAINS ALSO COMING INTO PLAY BY 

TUESDAY NIGHT. COULD SEE A COUPLE STRONG STORMS TUESDAY 

AFTERNOON/EVENING CONSIDERING AVAILABLE INSTABILITY AND ALSO 

POSSIBLY SOME LOCALLY HEAVY RAIN AS PRECIPITABLE WATERS REMAIN 

AROUND 2 INCHES. WILL SEE SOME RELIEF FROM THE HEAT NORTH OF THE 

FRONT /ALTHOUGH IT WILL REMAIN HUMID/...BUT KS ZONES LOOK TO CLIMB 

INTO THE UPPER 90S FOR HIGHS AS THEY REMAIN NEAR OR AHEAD OF THE 

FRONT THROUGH MUCH OF THE DAY. 



CONFIDENCE IN PRECIP CHANCES DWINDLES WITH TIME AS WOULD BE EXPECTED 

IN THIS TYPE OF PATTERN WHERE CHANCES HINGE LARGELY ON SMALL SCALE 

FEATURES THAT BECOME INHERENTLY LESS PREDICTABLE WITH TIME. THAT 

BEING SAID...WILL MAINTAIN SOME THUNDERSTORM CHANCES WEDNESDAY AND 

WEDNESDAY NIGHT EVEN THOUGH FRONT IS SOUTH OF THE AREA BY THIS 

TIME...DUE TO MOISTURE PLUME STILL EXTENDING EASTWARD ACROSS THE 

AREA ON EDGE OF UPPER RIDGE AND HINTS OF MID-LEVEL RIPPLES STILL 

IMPACTING THE AREA. WEDNESDAY NIGHT WILL FEATURE A LITTLE BETTER 

CHANCE AS HIGH PLAINS CONVECTION MAY PROPAGATE EAST/NORTHEAST

ALONG EDGE OF LLJ/H85 FRONTAL ZONE...WITH ADDITIONAL DEVELOPMENT

FARTHER EAST ALONG THIS ZONE POSSIBLE AS WELL. WILL TRY TO KEEP

THURSDAY DRY FOR THE TIME BEING AS PLUME OF MOISTURE TRIES TO SLIP

EAST BY THIS TIME...ALTHOUGH A LITTLE MORE PRONOUNCED SHORTWAVE

WILL BRING PRECIP CHANCES BACK TO AT LEAST NORTHWEST PORTIONS OF

THE AREA THURSDAY NIGHT. THIS SHOULD SLIDE EAST/NORTHEAST BY

FRIDAY...AND WILL MAINTAIN A DRY FORECAST FOR FRIDAY AND SATURDAY

WITH NOTHING TOO SOLID TO LATCH ONTO AT THIS POINT. TEMPS WILL BE

ON THE RISE ONCE AGAIN FRIDAY AND SATURDAY AS SOUTHERLY LOW-LEVEL

FLOW RETURNS AND MID/UPPER FLOW BECOMES MORE SOUTHWESTERLY.



&&



.GID WATCHES/WARNINGS/ADVISORIES...

NE...NONE.

KS...NONE.

&&



$$

AVIATION...EDDY