363 FXUS63 KDDC 030807 AFDDDC AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DODGE CITY KS 307 AM CDT THU MAY 3 2001 FORECAST CHALLENGE IS CONCERN FOR FLASH FLOODING PERIODS 2 AND 3. 03/00Z UPPER AIR ANALYSIS PLACED 5H LOW OVER CENTRAL UTAH. 7H BAROCLINIC ZONE WAS POSITIONED FROM SOUTHWEST CO TO SOUTHWEST NE TO NORTHERN MN. 8H BAROCLINIC ZONE WAS POSITIONED FROM CENTRAL NM TO JUST SOUTH OF AMA THEN NORTHEAST TO JUST WEST OF TOP AND THEN NORTHEAST THROUGH CENTRAL WISCONSIN. 03/06Z SFC ANALYSIS PLACED A 1010 MB SFC OVER HUT ICT WITH A SFC FRONT EXTENDING SOUTH FROM THIS LOW TO THE RED RIVER VALLEY AND THEN WEST INTO NEW MEXICO. AND ALSO NORTHEAST TO JUST NORTH OF MCI. OF THE AVN/ETA/NGM SOLUTIONS FOR 03/06Z...ONLY THE ETA HINTED OF THERE BEING A CLOSED LOW ALONG THE TROUGH AXIS OVER KS...BUT HAD IT POSITIONED CLOSER TO THE OK/KS LINE. GIVEN THIS THOUGH...WILL PREFER THE ETA/S SOLUTION TODAY FOR THE SFC LOW/FRONTAL POSITION AND SUBSEQUENT COLD AIR ADVECTION PATTERN IN THE SOUTHEAST PORTION OF THE FORECAST AREA. AVN/ETA/NGM MODEL GUIDANCE IS IN GOOD AGREEMENT OF DROPPING THE 5H LOW SLOWLY DUE SOUTH INTO NORTHERN NM BY 04/00Z. GIVEN THAT THE BEST HEIGHT FALLS ARE TO THE SOUTH AND SOUTHWEST OF THE LOW CENTER...AND A 100-110 KT JET WAS UPSTREAM OF THE LOW FROM CENTRAL BRITISH COLUMBIA INTO NORTHERN NEVADA...THESE SOLUTIONS APPEAR REASONABLE. HEIGHT CONTOURS WERE HANDLED BEST BY THE ETA WITH THE AVN AND NGM PROGRESSIVELY SLIGHTLY TOO HIGH ON HEIGHTS ACROSS KANSAS. THE MODELS WERE MIXED AS FAR AS INITIALIZATION OF TEMPERATURES GO. THE NGM/ETA DID FAIRLY WELL WITH TEMPS ACROSS KS/NE...BUT WERE UP TO 3 DEG C TOO COOL OVER THE TEXAS PANHANDLE. THE AVN WAS 2 DEG C TOO COOL OVER KS...BUT WAS RIGHT ON CONCERNING TEMPS OVER THE TEXAS PANHANDLE. MODEL SOLUTIONS ARE IN GOOD AGREEMENT OF THE GENERATION OF OVERRUNNING PRECIP TODAY. ON BOTH 295 AND 300K SFCS...CONSENSUS AMONG THE MODELS IS FOR ROUGHLY 4 TO 7 MB/HR PRESSURE ADVECTION THROUGH COMPLETELY SATURATED AIR. THE FOCUS FOR THE BEST OF THESE TWO FEATURES IS TARGETED OVER THE AREAS CLOSEST TO THE CO BORDER. CURRENTLY A 5H VORTMAX PASSING ACROSS THE AREA IS HELPING TO SPAWN SOME ISOLATED THUNDERSTORMS. THIS FEATURE IS PROGGED TO BE OVER MY EASTERN COUNTIES STILL BY 03/18Z AND THEN BE NORTHEAST OF THE AREA BY 04/00Z. GIVEN THIS...WILL CONFINE THUNDERSTORM WORDING TO THE EASTERN THIRD OF THE AREA WITH RAIN MENTIONED CENTRAL AND WEST. WILL GO CATEGORICAL WITH POPS TODAY ALL LOCATIONS. FOR TEMPS...PER DISCUSSION IN THE FIRST PARAGRAPH...WILL FAVOR THE COOLER FAN GUIDANCE FOR TODAY PARTICULARY IN THE SOUTHEAST WHERE FRONTAL POSITION AND WIND DIRECTION WILL BE KEY. FOR TONIGHT...YET ANOTHER 5H VORTMAX IS SCHEDULED TO HEAD NORTHEAST ACROSS THE CWA. WITH LITTLE CHANGE IN THE OVERALL LOW LEVEL ENVIRONMENT...THUNDERSTORMS LOOK PROMISING. SOME SEVERE HAILERS COULD BE POSSIBLE GIVEN THE MOISTENING OF THE COLUMN IN GENERAL AND A CONTINUED EXPECTED LOW WET BULB ZERO HEIGHT AROUND 11000 FT ASL. WILL CONTINUE WITH CATEGORICAL POPS. PRESSURE ADVECTION PER THE PREFERRED ETA JUMPS TO 10-12 MB/HR IN THE WEST WITH 3-5 IN THE EAST THROUGH A 80-100 RH LAYER AT THE 300K LEVEL AND TO 12-16 MB/HR ACROSS THE CWA AT THE 295K LEVEL. IN FACT...THIS PATTERN FOR TONIGHT IS EXPECTED THROUGHOUT THE ENTIRE COLUMN OF THE LOWER AND MID TROPOSPHERE. CONCERNED A BIT FOR THE POTENTIAL FOR FLASH FLOODING...NOT SO MUCH FOR THE STATOFORM RAIN...BUT THIS RAIN COMBINED WITH ISOLATED HEAVIER CONVECTIVE RAINS FROM THUNDERSTORMS. IF I WERE TO PLACE A WATCH ATTM...I WOULD FOCUS ON THE SOUTHEAST PORTION OF THE CWA IN THE VICINITY OF THE SFC FRONT. BUT FOR NOW...WILL HOLD OFF ON THIS. DAY SHIFT WILL HAVE THE BENEFIT OF KNOWING RAINFALL TOTALS DURING THURSDAY AND WILL BE ABLE TO BETTER JUDGE WHEN/IF/WHERE A FLASH FLOOD WATCH IS NEEDED. LOW TEMPERATURES SHOULD BE A LITTLE HIGHER THAN THOSE EXPECTED THIS MORNING. FOR FRIDAY...THE NEW MEXICO CLOSED LOW IS PROGGED TO BEGIN SLOWLY LIFTING NORTHEAST. THIS SHOULD HAVE THE EFFECT OF HELPING OUR PESKY SFC FRONT LIFT NORTH AS A WARM FRONT. THIS WOULD ALSO PLACE THE FOCUS FOR THE BEST PRECIP CHANCES NORTH OF THE FORECAST AREA WITH PERHAPS EVEN MY SOUTHWEST COUNTIES BECOMING DRY-SLOTTED BY LATE AFTERNOON. HOWEVER...MUCH OF THE DAY FRIDAY THE AREA SHOULD EXPERIENCE WEATHER SIMILAR OF THAT EXPECTED TONIGHT WITH HEAVY RAINFALL STILL A POSSIBILITY. FOR SAKE OF CONTINUITY WILL CONTINUE TO FAVOR THE FAN GUIDANCE. AGAIN IF FLASH FLOODING POTENTIAL IS THERE FOR THURSDAY NIGHT...THE CONCERN WILL THEN TRANSLATE INTO FRIDAY. EXTENDED DISCUSSION... GOING EXTENDED FORECAST IS ON TRACK FOR THE EARLY PERIODS AS THE UPPER LOW OVER THE SOUTHWEST CONUS IS FINALLY PROGGED TO LIFT OUT BY SUNDAY. AFTER THAT THE MODELS WANDER OFF IN MANY DIFFERENT DIRECTIONS AND CONFIDENCE IN ANY OF THEIR SOLUTIONS IS LOW. WILL CHANGE NOTHING IN THE EARLY PERIODS AND WILL HOLD MY HAND OVER MY EYES FOR THE LATER PERIODS. PRELIMINARY GUIDANCE FOR COORDINATION ONLY. OFFICIAL FORECASTS ARE CONTAINED WITHIN THE DODGE CITY ZONE FORECAST. DDC 056/052 067/056 070 +++ GCK 054/051 064/055 067 +++ EHA 052/048 062/052 065 +++ LBL 056/052 066/056 069 +++ HYS 056/052 066/056 069 +++ P28 064/060 070/064 073 +++ .DDC...NONE. SLEIGHTER/JOHNSON  363 FXUS63 KDDC 030807 AFDDDC AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DODGE CITY KS 307 AM CDT THU MAY 3 2001 FORECAST CHALLENGE IS CONCERN FOR FLASH FLOODING PERIODS 2 AND 3. 03/00Z UPPER AIR ANALYSIS PLACED 5H LOW OVER CENTRAL UTAH. 7H BAROCLINIC ZONE WAS POSITIONED FROM SOUTHWEST CO TO SOUTHWEST NE TO NORTHERN MN. 8H BAROCLINIC ZONE WAS POSITIONED FROM CENTRAL NM TO JUST SOUTH OF AMA THEN NORTHEAST TO JUST WEST OF TOP AND THEN NORTHEAST THROUGH CENTRAL WISCONSIN. 03/06Z SFC ANALYSIS PLACED A 1010 MB SFC OVER HUT ICT WITH A SFC FRONT EXTENDING SOUTH FROM THIS LOW TO THE RED RIVER VALLEY AND THEN WEST INTO NEW MEXICO. AND ALSO NORTHEAST TO JUST NORTH OF MCI. OF THE AVN/ETA/NGM SOLUTIONS FOR 03/06Z...ONLY THE ETA HINTED OF THERE BEING A CLOSED LOW ALONG THE TROUGH AXIS OVER KS...BUT HAD IT POSITIONED CLOSER TO THE OK/KS LINE. GIVEN THIS THOUGH...WILL PREFER THE ETA/S SOLUTION TODAY FOR THE SFC LOW/FRONTAL POSITION AND SUBSEQUENT COLD AIR ADVECTION PATTERN IN THE SOUTHEAST PORTION OF THE FORECAST AREA. AVN/ETA/NGM MODEL GUIDANCE IS IN GOOD AGREEMENT OF DROPPING THE 5H LOW SLOWLY DUE SOUTH INTO NORTHERN NM BY 04/00Z. GIVEN THAT THE BEST HEIGHT FALLS ARE TO THE SOUTH AND SOUTHWEST OF THE LOW CENTER...AND A 100-110 KT JET WAS UPSTREAM OF THE LOW FROM CENTRAL BRITISH COLUMBIA INTO NORTHERN NEVADA...THESE SOLUTIONS APPEAR REASONABLE. HEIGHT CONTOURS WERE HANDLED BEST BY THE ETA WITH THE AVN AND NGM PROGRESSIVELY SLIGHTLY TOO HIGH ON HEIGHTS ACROSS KANSAS. THE MODELS WERE MIXED AS FAR AS INITIALIZATION OF TEMPERATURES GO. THE NGM/ETA DID FAIRLY WELL WITH TEMPS ACROSS KS/NE...BUT WERE UP TO 3 DEG C TOO COOL OVER THE TEXAS PANHANDLE. THE AVN WAS 2 DEG C TOO COOL OVER KS...BUT WAS RIGHT ON CONCERNING TEMPS OVER THE TEXAS PANHANDLE. MODEL SOLUTIONS ARE IN GOOD AGREEMENT OF THE GENERATION OF OVERRUNNING PRECIP TODAY. ON BOTH 295 AND 300K SFCS...CONSENSUS AMONG THE MODELS IS FOR ROUGHLY 4 TO 7 MB/HR PRESSURE ADVECTION THROUGH COMPLETELY SATURATED AIR. THE FOCUS FOR THE BEST OF THESE TWO FEATURES IS TARGETED OVER THE AREAS CLOSEST TO THE CO BORDER. CURRENTLY A 5H VORTMAX PASSING ACROSS THE AREA IS HELPING TO SPAWN SOME ISOLATED THUNDERSTORMS. THIS FEATURE IS PROGGED TO BE OVER MY EASTERN COUNTIES STILL BY 03/18Z AND THEN BE NORTHEAST OF THE AREA BY 04/00Z. GIVEN THIS...WILL CONFINE THUNDERSTORM WORDING TO THE EASTERN THIRD OF THE AREA WITH RAIN MENTIONED CENTRAL AND WEST. WILL GO CATEGORICAL WITH POPS TODAY ALL LOCATIONS. FOR TEMPS...PER DISCUSSION IN THE FIRST PARAGRAPH...WILL FAVOR THE COOLER FAN GUIDANCE FOR TODAY PARTICULARY IN THE SOUTHEAST WHERE FRONTAL POSITION AND WIND DIRECTION WILL BE KEY. FOR TONIGHT...YET ANOTHER 5H VORTMAX IS SCHEDULED TO HEAD NORTHEAST ACROSS THE CWA. WITH LITTLE CHANGE IN THE OVERALL LOW LEVEL ENVIRONMENT...THUNDERSTORMS LOOK PROMISING. SOME SEVERE HAILERS COULD BE POSSIBLE GIVEN THE MOISTENING OF THE COLUMN IN GENERAL AND A CONTINUED EXPECTED LOW WET BULB ZERO HEIGHT AROUND 11000 FT ASL. WILL CONTINUE WITH CATEGORICAL POPS. PRESSURE ADVECTION PER THE PREFERRED ETA JUMPS TO 10-12 MB/HR IN THE WEST WITH 3-5 IN THE EAST THROUGH A 80-100 RH LAYER AT THE 300K LEVEL AND TO 12-16 MB/HR ACROSS THE CWA AT THE 295K LEVEL. IN FACT...THIS PATTERN FOR TONIGHT IS EXPECTED THROUGHOUT THE ENTIRE COLUMN OF THE LOWER AND MID TROPOSPHERE. CONCERNED A BIT FOR THE POTENTIAL FOR FLASH FLOODING...NOT SO MUCH FOR THE STATOFORM RAIN...BUT THIS RAIN COMBINED WITH ISOLATED HEAVIER CONVECTIVE RAINS FROM THUNDERSTORMS. IF I WERE TO PLACE A WATCH ATTM...I WOULD FOCUS ON THE SOUTHEAST PORTION OF THE CWA IN THE VICINITY OF THE SFC FRONT. BUT FOR NOW...WILL HOLD OFF ON THIS. DAY SHIFT WILL HAVE THE BENEFIT OF KNOWING RAINFALL TOTALS DURING THURSDAY AND WILL BE ABLE TO BETTER JUDGE WHEN/IF/WHERE A FLASH FLOOD WATCH IS NEEDED. LOW TEMPERATURES SHOULD BE A LITTLE HIGHER THAN THOSE EXPECTED THIS MORNING. FOR FRIDAY...THE NEW MEXICO CLOSED LOW IS PROGGED TO BEGIN SLOWLY LIFTING NORTHEAST. THIS SHOULD HAVE THE EFFECT OF HELPING OUR PESKY SFC FRONT LIFT NORTH AS A WARM FRONT. THIS WOULD ALSO PLACE THE FOCUS FOR THE BEST PRECIP CHANCES NORTH OF THE FORECAST AREA WITH PERHAPS EVEN MY SOUTHWEST COUNTIES BECOMING DRY-SLOTTED BY LATE AFTERNOON. HOWEVER...MUCH OF THE DAY FRIDAY THE AREA SHOULD EXPERIENCE WEATHER SIMILAR OF THAT EXPECTED TONIGHT WITH HEAVY RAINFALL STILL A POSSIBILITY. FOR SAKE OF CONTINUITY WILL CONTINUE TO FAVOR THE FAN GUIDANCE. AGAIN IF FLASH FLOODING POTENTIAL IS THERE FOR THURSDAY NIGHT...THE CONCERN WILL THEN TRANSLATE INTO FRIDAY. EXTENDED DISCUSSION... GOING EXTENDED FORECAST IS ON TRACK FOR THE EARLY PERIODS AS THE UPPER LOW OVER THE SOUTHWEST CONUS IS FINALLY PROGGED TO LIFT OUT BY SUNDAY. AFTER THAT THE MODELS WANDER OFF IN MANY DIFFERENT DIRECTIONS AND CONFIDENCE IN ANY OF THEIR SOLUTIONS IS LOW. WILL CHANGE NOTHING IN THE EARLY PERIODS AND WILL HOLD MY HAND OVER MY EYES FOR THE LATER PERIODS. PRELIMINARY GUIDANCE FOR COORDINATION ONLY. OFFICIAL FORECASTS ARE CONTAINED WITHIN THE DODGE CITY ZONE FORECAST. DDC 056/052 067/056 070 +++ GCK 054/051 064/055 067 +++ EHA 052/048 062/052 065 +++ LBL 056/052 066/056 069 +++ HYS 056/052 066/056 069 +++ P28 064/060 070/064 073 +++ .DDC...NONE. SLEIGHTER/JOHNSON