Area Forecast Discussion
Issued by NWS Goodland, KS

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000
FXUS63 KGLD 132330
AFDGLD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GOODLAND KS
530 PM MDT SAT SEP 13 2014

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 127 PM MDT SAT SEP 13 2014

UPPER FLOW WILL BE WESTERLY TONIGHT AND SUNDAY.  SURFACE HIGH
PRESSURE WILL CONTINUE OVER THE CENTRAL PLAINS TONIGHT AND DRIFT
EAST SUNDAY AS A SURFACE TROUGH MOVES INTO EASTERN COLORADO.

THE WEATHER WILL REMAIN DRY TONIGHT AND SUNDAY WITH SUBSIDENCE OVER
THE AREA. SOME DYNAMICS FROM A WEAK SHORTWAVE WILL APPROACH THE
EASTERN ZONES LATE SUNDAY AFTERNOON. POPS WILL BE NIL TONIGHT AND
SUNDAY MORNING WITH SOME SILENT POPS IN EASTERN COLORADO SUNDAY
AFTERNOON.

BOUNDARY LAYER RH INCREASES AGAIN LATER TONIGHT INTO SUNDAY MORNING.
PLAN TO INTRODUCE SOME STRATUS ACROSS THE WESTERN 2 TIERS OF THE
NORTHWEST KANSAS ZONES. SINCE RH IS UNDER 90 PERCENT WILL LEAVE
OUT PATCHY FOG.

MIN TEMPERATURES TONIGHT WILL NOT BE AS COLD WITH READINGS IN THE
MID 40S. MAX TEMPERATURES SUNDAY SHOULD RISE TO THE MID/UPPER 70S
WITH AROUND 80 POSSIBLE IN THE SOUTHWEST PORTION OF THE FA.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 155 PM MDT SAT SEP 13 2014

FORECAST CONCERNS WILL BE CHANCE OF PRECIPITATION SUNDAY NIGHT
INTO MONDAY AND HIGH TEMPERATURES MONDAY AND TUESDAY. SATELLITE
SHOWING AN AMPLIFIED PATTERN FROM THE EASTERN PACIFIC INTO WESTERN
NORTH AMERICA. THIS TRANSITIONS INTO A MORE BROAD/PROGRESSIVE FLOW
OVER THE REST OF THE COUNTRY INTO THE EASTERN ATLANTIC.

MODELS LOOKED TO START OUT FINE AT MID AND UPPER LEVELS. HOWEVER
AT MID LEVELS...THE GFS...CANADIAN AND UKMET WERE DOING A LITTLE
BETTER. THE ECMWF...SREF AND NAM WERE DOING THE BEST ON THE
SURFACE WIND AND PRESSURE FIELD. MODELS WERE HAVING TROUBLE ON THE
LOW LEVEL TEMPERATURES AND TENDED TO BE TOO WARM. THE GFS...CANADIAN
AND ECMWF WERE DOING THE BEST AT THIS TIME.

SUNDAY NIGHT...MODELS HAVE THEIR DIFFERENCES BUT A MAJORITY OF
THEM ARE INDICATING A RIGHT REAR QUADRANT OVER THE NORTHERN AND
CENTRAL PORTION OF THE AREA FROM LATE IN THE EVENING THROUGH THE
REST OF THE NIGHT. THIS LIFT TRANSLATES SLOWLY NORTH TO SOUTH
DURING THIS TIME. SO WILL ACTUALLY BE IN SUBSIDENCE FROM THE JET.

ALSO MODELS CONTINUE TO KEEP THE MID LEVELS DRY. NEW MODEL RUN IS
FURTHER NORTH AND SLOWER WITH THE MID LEVEL LIFT. SO KEPT POPS OUT
UNTIL MID EVENING WITH THE HIGHEST POPS AFTER MIDNIGHT. HIGHEST
POPS WILL BE IN THE NORTHEAST THIRD. THERE IS A LOT OF ELEVATED
CAPE BUT INHIBITION IS RATHER HIGH TOO. STORMS COULD POSSIBLY GET
STRONG DURING THIS TIME.

MODELS STILL SHOW FRONT MOVING THROUGH THE ENTIRE AREA BY THE END
OF THE NIGHT. MODELS ALSO SHOW AN EXTENSIVE STRATUS DECK FOLLOWING
BEHIND IT. MODELS INDICATING FOG...ESPECIALLY ALONG THE FRONT AND
LOCALLY DENSE AS WELL. SO INCREASED CLOUD COVER AFTER MIDNIGHT AND
REINTRODUCED FOG.

MONDAY/MONDAY NIGHT...CONTINUED THE TREND ON POPS FROM THE PREVIOUS
PERIOD. HIGHEST POPS SHOULD CONTINUE TO BE IN THE NORTH AND
EAST...AND IN THE MORNING...AS SHORTWAVE TROUGH MOVES THROUGH.
THERE COULD BE SOME LINGERING PRECIPITATION IN THE FAR EAST IN THE
EARLY AFTERNOON.

MODELS CONTINUE TO SHOW A THICK LOW LEVEL CLOUD DECK WITH SOME FOG
THROUGH THE MORNING HOURS. AM VERY CONCERNED WITH HIGH TEMPERATURES
BEING TOO WARM BECAUSE OF THIS AND THE POSSIBILITY OF THE MODELS
CLEARING THE CLOUDS OUT TOO FAST BECAUSE OF THE UPSLOPE FLOW.
COMBINE THAT WITH THE FACT THAT THERE LOOKS TO BE LINGERING
PRECIPITATION IN THE MORNING. THIS COMBINED WITH THE UPSLOPE WINDS
AND COOLER LOW LEVEL TEMPERATURES WILL KEEP HIGH TEMPERATURES
COOLER THAN WHAT THE PREVIOUS GRIDS HAD. SO LOWERED THEM ABOUT 3
DEGREES. HOWEVER...THIS IS HIGHLY DEPENDENT ON WHEN THE CLOUD
COVER BREAKS UP...WHICH THE MODELS RECENTLY HAVE BEEN UNDERDOING
AND CLEARING OUT TOO FAST IN THE DAY.

AS HAS BEEN REALITY THE LAST FEW NIGHTS...MODELS ARE DEPICTING
STRATUS AND FOG RETURNING TO THE AREA AS THE RETURN FLOW SETS UP
OVER THE WESTERN PORTION OF THE AREA, WILL HAVE TO MAKE SURE CLOUD
COVER IS INCREASED APPROPRIATELY AND HAVE ALSO INTRODUCED FOG
SINCE THIS HAS BEEN THE PATTERN LATELY. THE FAR EASTERN PORTION OF
THE AREA LOOKS TO HAVE MUCH LESS CLOUD COVER AND LIGHTER WINDS. SO
MADE THEIR MINS COOLER THAN IN THE WEST WHICH WILL HAVE STRATUS BY
LATE IN THE NIGHT.

TUESDAY...ONCE AGAIN HIGH TEMPERATURES WILL BE DETERMINED BY HOW
LONG THE STRATUS HOLDS ON. MOST OF THE CLOUD COVER WILL STAY IN
THE WEST WITH A MAJORITY OF THE CLOUD COVER TO BE GONE BY LATE IN
THE MORNING. TENDED TO TOWARD THE COOLER FORECAST MAXES DUE TO
RECENT TRENDS AND EXPECTED 850 MB TEMPERATURES.

TUESDAY NIGHT THROUGH SATURDAY...

ONCE AGAIN MODELS START WITH DIFFERENCES IN REGARDS TO HOW THEY
HANDLE THE RIDGE THAT IS FORECAST TO MOVE/BUILD INTO THE AREA. THIS
IS AFFECTED BY HOW THEY HANDLE THE TROUGHINESS ALONG THE WEST COAST.
DETERMINISTIC AND ENSEMBLE MODEL SPREAD GETS EXTREMELY WIDE THE
LAST TWO DAYS OF THIS FORECAST. FORECAST ALSO MADE MORE COMPLICATED
DUE TO THE POSSIBILITY OF THE REMNANTS OF A TROPICAL STORM MOVING
INTO/GETTING INVOLVED WITH FLOW FROM THE SOUTHWEST.

THE 00Z ECMWF AND CANADIAN WERE MORE IN LINE WITH EACH OTHER. BY THE
END OF THE PERIOD...THE 00Z ECMWF AND THE NEWEST GFS WERE COMPLETELY
OUT OF PHASE. THE 00Z ECMWF WAS SHOWING A CUTOFF LOW DEVELOPING FROM
700 TO 500 MB FROM CENTRAL COLORADO INTO WESTERN KANSAS. ENSEMBLES
DO SUPPORT TROUGHINESS MOVING INTO THE REGION BUT NOT TO THE DEGREE
THAT THE 00Z ECMWF WAS DOING.

HOWEVER...THE 12Z ECMWF HAS DONE ALMOST A COMPLETE REVERSAL WITH
A MUCH STRONGER RIDGE OVER THE AREA BY THE END OF THE PERIOD NO
SIGN OF ANY CUTOFF CLOSE. IN FACT THE 12Z ECMWF IS COMPLETELY OUT
OF PHASE WITH THE 00Z ECMWF WHICH LOWERS CONFIDENCE DRAMATICALLY.
THE LATEST GEFS OUTPUT MAKES THE NEW ECMWF AN OUTLIER AND ADDS
SUPPORT TO THE GFS. THIS MAKES THE END OF THE EXTENDED HIGHLY
UNCERTAIN AND PROBLEMATIC TO RESOLVE THIS FAR OUT.

BASED ON REASONING ABOVE AND COLLABORATION WITH MY
NEIGHBORS...CHOSE TO NOT ONLY LEAVE THE POPS FROM FRIDAY INTO
SATURDAY ALONE BUT ALSO ALL THE CRH_INIT GAVE ME. THE POPS ARE
PRETTY HIGH FOR SEVEN DAYS OUT. AT THIS TIME THEY GET AS HIGH AS
HIGH CHANCE TO LOW LIKELY. STAY TUNED TO HOW THIS TURNS OUT.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 530 PM MDT SAT SEP 13 2014

VFR CONDITIONS SHOULD PREVAIL DURING THE FIRST 6 HR OF THE TAF
PERIOD AT BOTH KGLD AND KMCK. LESS CERTAINTY AFTER 06Z AS GOOD
RADIATIONAL CONDITIONS MAY LEAD TO SATURATION OF THE LOWER LEVELS
AND STRATUS/FOG DEVELOPMENT...THOUGH LATEST STATISTICAL GUIDANCE
DOES NOT SHOW THIS. THERE MAY BE JUST ENOUGH BL MIXING TO SUPPORT
MORE OF A STRATUS EVENT...THOUGH NAM AND LATEST SHORT RANGE
GUIDANCE ARE SHOWING IFR/LIFR VIS OVER PARTS OF SW NEBRASKA. THIS
MAY BE END UP BEING MAINLY TO THE RIVER VALLEYS...AND COULD IMPACT
KMCK. I WAS NOT CONFIDENT ENOUGH TO INTRODUCE MORE THAN MVFR
CIG/VIS GROUPS TO KGLD/KMCK SUNDAY MORNING. IMPROVEMENT SHOULD
OCCUR BY MID MORNING SUNDAY WITH DAYTIME HEATING.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&

$$

SHORT TERM...FS
LONG TERM...BULLER
AVIATION...DR



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