Area Forecast Discussion Issued by NWS Goodland, KS
000
FXUS63 KGLD 241751
AFDGLD
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GOODLAND KS
1151 AM MDT FRI MAY 24 2013
.UPDATE...
ISSUED AT 819 AM MDT FRI MAY 24 2013
MADE A FEW CHANGES TO THE FORECAST FOR TODAY. THE FIRST BEING
TO INCREASE THE WINDS FOR TODAY...ESPECIALLY DURING THE MORNING.
WINDS HAVE BEEN VARYING QUITE A BIT OVER THE PAST COUPLE OF HOURS.
HAVE BEEN CONTEMPLATING A WIND ADVISORY FOR THE WESTERN 2/3S OF
THE AREA. BIGGEST UNCERTAINTY IS WILL THE SUSTAINED WINDS REMAIN
AT 30 MPH OR CONTINUE TO VARY. IN ADDITION THE WINDS MAY
STRENGTHEN DURING THE AFTERNOON BEHIND THE WARM FRONT. AT THIS
POINT WILL ONLY INCREASE THE SUSTAINED WINDS TO JUST UNDER 30 MPH
FOR THE REST OF THE DAY FOR THE MAJORITY OF THE AREA...WHICH IS
JUST UNDER WIND ADVISORY CRITERIA. IF CRITERIA IS REACHED AM
CONFIDENT IT WILL BE VERY LOW END.
ALSO REMOVED THE MENTION OF FOG FOR ALL BUT EAST CENTRAL COLORADO
THIS MORNING. WEB CAMS AT FIRST VIEW AND GENOA BOTH SHOW
VISIBILITIES OF LESS THAN A MILE. DUE TO THE RATHER SMALL AREA
BEING AFFECTED AND SINCE THE FOG WILL BEGIN TO LIFT IN THE NEXT
HOUR OR SO...WILL NOT BE ISSUING ANY FOG RELATED HAZARDS.
DID DROP THE CHANCES FOR PRECIP. DOWN SOME THIS MORNING OVER THE
EAST. MODELS DO SHOW A MINOR UPPER LEVEL SHORT WAVE TROUGH MOVING
THROUGH...HOWEVER SOUNDINGS DO NOT LOOK VERY FAVORABLE FOR STORM
DEVELOPMENT THIS MORNING. WILL LEAVE A SLIGHT CHANCE IN...BUT THIS
MAY BE TOO MUCH FOR THE MORNING.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 434 AM MDT FRI MAY 24 2013
FORECAST PROBLEMS WILL BE NUMEROUS THROUGH THE WEEKEND. SATELLITE
SHOWING A FASTER/MORE PROGRESSIVE FLOW OVER THE PACIFIC WHICH THEN
TRANSITIONS TO A SLOWER AND MORE AMPLIFIED FLOW OVER NORTH AMERICA.
THE RIDGE OVER THE CENTRAL PORTION OF THE COUNTRY HAS INCREASED IN
AMPLITUDE OVER THE LAST 24 HOURS. UPPER LOW OVER THE PACIFIC
NORTHWEST HAS MOVED LITTLE IN THE LAST 24 HOURS. FRONT THAT MOVED
THROUGH YESTERDAY REMAINS DRAPED WELL SOUTH AND WEST OF THE AREA AT
THIS TIME.
THE SREF...NAM AND CANADIAN INITIALIZED BEST ON THE JET LEVEL WINDS
OVER OUR AREA. MODELS HAVING A LITTLE TROUBLE WITH THE DETAILS AT
MID LEVELS. OVERALL THE SREF AND NAM WERE DOING SLIGHTLY BETTER THAN
THE GFS...CANADIAN AND CANADIAN. THE NAM LOOKED LIKE IT WAS CATCHING
THE MINOR SHORTWAVE TROUGH TO OUR SOUTHWEST THE BEST. THE GFS WAS
DOING SLIGHTLY BETTER THAN THE ECMWF ON THE LOW LEVEL THERMAL FIELD.
THE GFS WAS TOO AGGRESSIVE WITH THE LOW LEVEL MOISTURE RETURN WITH
THE NAM DOING A LITTLE BETTER. MODELS DO NOT QUITE HAVE THE BOUNDARY
TO OUR SOUTH QUITE FAR ENOUGH SOUTH. THE NAM WAS DOING A LITTLE
BETTER HERE. ALSO MODELS HAD QPF TOO FAR NORTH BY 06Z WITH THE GFS...
CANADIAN AND THE SREF THE WORST OFFENDERS. AGAIN THE NAM WAS DOING
BETTER HERE.
TODAY/TONIGHT...MOST OF THE MODEL OUTPUT SHOWS A WEAK LEFT FRONT
QUADRANT OVER THE AREA BEGINNING NEAR 12Z AND MAINLY AFFECTING THE
SOUTHEAST HALF. A SMALL CLUSTER OF THUNDERSTORMS HAD DEVELOPED OVER
NORTHEAST NEW MEXICO AND THE PANHANDLE AREA. THIS LOOKS TO BE IN
RESPONSE TO SHORTWAVE TROUGH AND THE WEAK LEFT FRONT QUADRANT OF THE
JET. HOWEVER THAT DISSIPATED WITH ISOLATED THUNDERSTORMS DEVELOPING
OVER/NEAR THE EASTERN PORTION OF THE AREA.
THE NAM FOR THE MOST PART HAS THIS AREA DEPICTED WELL...ESPECIALLY
FOR THE JET. SO GOING BY THAT...WILL HAVE A SLIGHT CHANCE TO CHANCE
OF THUNDERSTORMS THROUGH MAINLY THE MORNING WITH IT POSSIBLY
LINGERING INTO EARLY AFTERNOON IN THE FAR EAST. STRATUS IS MOSTLY
OCCURRING OVER THE AREA AT THIS TIME WITH THE FOG CONFINED TO EASTERN
COLORADO. THIS MAKES SENSE WITH THIS BEING THE MAIN AREA OF LOW LEVEL
TRANSPORT OF MOISTURE AT THIS TIME. THE HRRR AND NAM INDICATE THE
BEST CHANCE OF FOG OVER THE WESTERN HALF OF THE AREA. A FEW SPOTS
ALSO REPORTING DRIZZLE AND SOUNDINGS WOULD INDICATE THAT WILL
CONTINUE INTO THIS MORNING. SO WILL HAVE AREAS OF FOG WITH PATCHY
DRIZZLE IN THE WESTERN HALF AND PATCHY FOG FURTHER EAST.
SOUTHERLY WINDS INCREASE INTO THE WINDY CATEGORY. GRADIENT DEFINITELY
SUPPORTS NEAR ADVISORY CRITERIA IN THE WEST BUT THERE THE 3 HOUR
PRESSURE FALLS ARE NOT THAT HIGH. GLD VWP DEFINITELY WOULD
SUPPORT WINDY. WILL RAISE WINDS TO NEAR ADVISORY IN THE FAR WEST.
NOW FOR THE PRECIPITATION CHANCES DURING THE AFTERNOON AND NIGHT.
SUBSIDENCE/DRYING OCCURS OUT EAST RATHER QUICKLY AFTER FIRST
SHORTWAVE. INSTABILITY AXIS...BEST HEATING...MID/UPPER LEVEL LIFT
AND SURFACE CONVERGENCE DEVELOPS NEAR OR OVER THE WESTERN PORTION OF
THE AREA. SO WILL GRADUALLY RAMP UP POPS DURING THE AFTERNOON. BEST
LIFT AND MOISTURE LOOK TO RESIDE OVER THE NORTH DURING THE NIGHT
AND HAVE INCREASED POPS OVER THE NORTH WITH LOWER POPS FURTHER
SOUTH. THUNDERSTORMS LOOK TO BE DONE BY 12Z. LOW LEVEL MOISTURE
INCREASES OVER THE EASTERN HALF TO TWO THIRDS AFTER 06Z. AT THIS TIME
MODELS INDICATING MOSTLY STRATUS. WILL INSERT FOG WITH THE GREATEST
CHANCE IN THE FAR EAST.
NOT A GOOD FEEL ON THE MAXES WITH THEM BEING DETERMINED BY THE
EXTENT OF THE STRATUS AND HOW LONG IT TAKES TO BURN OFF. IT IS
POSSIBLE THAT THICK CLOUD COVER WILL NOT BREAK UP UNTIL LATE
MORNING. SO TRENDED THE FORECAST COOLER.
SATURDAY/SATURDAY NIGHT...FOG WILL CLEAR OUT DURING THE MORNING.
MODELS NOT AGREEING WHERE DRY LINE ENDS UP...WHERE THE INSTABILITY
AXIS ENDS UP...WHERE THE CAP IS THE LEAST...AND SHORTWAVE DETAILS.
AT THIS TIME IT LOOKS LIKE THE DRY LINE ENDS UP NEAR OR A LITTLE
WEST OF THE COLORADO BORDER. ONE SHORTWAVE TROUGH EXITS THE EASTERN
PORTION OF THE AREA EARLY IN THE AFTERNOON WITH ANOTHER ONE
APPROACHING LATE IN THE AFTERNOON WITH THE BRUNT OF ITS LIFT COMING
THROUGH DURING THE NIGHT. MODELS ARE GENERATING QPF WHERE THERE IS
A STRONG CAP.
AS IT LOOKS NOW THE MAIN TIME FOR PRECIPITATION WILL WAIT TO BEGIN
UNTIL MID TO LATE EVENING. THE BEST CHANCE FOR THUNDERSTORMS WILL
BE EAST OF THE COLORADO BORDER...AND ESPECIALLY IN THE FAR EAST.
LOW LEVEL THERMAL FIELD IS MUCH WARMER THAN TODAYS. HOWEVER...IF
STRATUS/FOG LAST LONGER OR THE LEE TROUGH IS STRONGER/FURTHER WEST...
THE WINDS WILL BE MORE FROM AN EASTERLY DIRECTION AND NOT ALLOW FOR
AS BIG A WARM UP. KEPT THE WESTERN AREAS WARMER WITH COOLER MAXES
FURTHER EAST.
IN REGARDS TO FIRE...THE LOWEST RHS LOOK TO BE IN COLORADO AT THIS
TIME. HOWEVER...THAT IS WHERE THE LIGHTEST WIND FIELD IS. DUE TO A
LOT OF UNCERTAINTY...WAS NOT CONFIDENT ENOUGH TO THROW OUT A WATCH.
WILL HIGHLIGHT IN THE FIRE WEATHER FORECAST AND HWO.
SUNDAY/SUNDAY NIGHT...A LOT MORE DISAGREEMENT IN DETAILS SHOW UP IN
THIS PERIOD. CURRENT MODEL OUTPUT SUPPORTED THE GOING PRECIPITATION
FORECAST FOR THIS PERIOD AND LEFT IT ALONE. ALSO ONLY MADE SLIGHT
ADJUSTMENTS TO THE TEMPERATURE FORECAST AS WELL. P
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 235 AM MDT FRI MAY 24 2013
MEDIUM RANGE MODEL DIFFERENCES EMERGE EARLY IN THE EXTENDED
PERIOD...PARTICULARLY WITH REGARD TO AMPLITUDE OF UPPER FLOW
PATTERN. THE ECMWF IS MORE AMPLIFIED ON MONDAY WITH BOTH THE UPPER
RIDGE POSITIONED TO OUR EAST AND ALSO THE WESTERN CONUS UPPER
TROUGH. THE POSITION OF THESE FEATURES WILL PLACE OUR AREA IN
SOUTHWESTERLY FLOW ALOFT WITH THE LIKELIHOOD OF WEAK EMBEDDED
DIFFICULT TO TIME SHORTWAVES THAT COULD POTENTIALLY ENHANCE
PRECIPITATION DEVELOPMENT. BY TUESDAY THE PATTERN AMPLIFIES
FURTHER AND ECMWF CLOSES OFF AN UPPER LOW OVER THE SOUTHWEST
CONUS. GFS MAINTAINS AN OPEN WAVE AND SHIFTS IT EASTWARD WITH
NOTICEABLE HEIGHT FALLS OVER OUR AREA BY LATE TUESDAY AND
ESPECIALLY WEDNESDAY. THE NEW 00Z ECMWF HAS TRENDED THE DIRECTION
OF THE MORE PROGRESSIVE GFS AND OPENS UP THE SOUTHWEST CONUS UPPER
LOW RATHER THAN KEEP IT CLOSED AND SLOWLY MOVING IT EAST AS THE
12Z ECMWF INDICATED. STILL THE ECMWF IS CONSIDERABLY SLOWER THAN
THE GFS WITH THE EASTWARD PROGRESSION OF THIS TROUGH. THIS LEADS
TO A LOW CONFIDENCE FORECAST NEXT WEEK. GFS WOULD FAVOR A
POTENTIALLY WIDESPREAD PRECIPITATION / ORGANIZED CONVECTIVE EVENT
WEDNESDAY WHILE THE ECMWF SOLUTION WOULD SUPPORT A SIMILAR
SITUATION BY LATE WEDNESDAY / WEDNESDAY NIGHT INTO THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1142 AM MDT FRI MAY 24 2013
MVFR TO VFR CONDITIONS ARE FORECAST FOR THE 18Z TAFS. VISIBLE
SATELLITE IMAGERY SHOWS LOW CLOUDS DEPARTING THE AREA. EXPECT KMCK
TO BE OUT OF THE LOW CLOUDS SHORTLY AFTER TAF ISSUANCE. AS THE
CLOUDS CLEAR WINDS HAVE NOT STRENGTHENED MUCH AT ALL SO FAR...SO
AM EXPECTING THIS TO CONTINUE. HOWEVER WINDS WILL REMAIN BREEZY
THROUGH THE EVENING BEFORE SLOWING DURING THE OVERNIGHT HOURS.
LATER THIS AFTERNOON/EARLY EVENING THUNDERSTORMS WILL DEVELOP OVER
EASTERN COLORADO AND DEVELOP/PROGRESS EASTWARD. THE BEST CHANCE
FOR STORMS NEAR KGLD WILL BE AROUND 0Z...WITH STORMS DISSIPATING
AFTER A FEW HOURS. STRONG TO SEVERE WIND GUSTS WILL BE POSSIBLE
THROUGH THE EARLY EVENING WITH ANY STORMS THAT DEVELOP. FOR KMCK THE BEST
CHANCE WILL BE AROUND 6Z WITH STORMS MOVING EAST OF THE SITE BY
10Z. THERE MIGHT BE SOME FOG DEVELOPMENT AT KMCK LATE TONIGHT.
HOWEVER CURRENT DATA SUGGESTS ONLY A REDUCTION TO MVFR AT
BEST...SO WILL HOLD OFF PLACING A MENTION OF FOG IN FOR KMCK FOR
THIS TAF ISSUANCE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...BRB
AVIATION...JTL