081
FXUS63 KGLD 091126
AFDGLD
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GOODLAND KS
425 AM MST TUE FEB 9 2010
DISCUSSION
235 AM MST TUE FEB 9 2010
FORECAST PROBLEMS WILL BE HOW COLD TO MAKE TODAY...HOW MUCH TO WARM
UP TEMPERATURES THROUGH THURSDAY...ESPECIALLY THURSDAY...AND THE
POSSIBILITIES OF STRATUS/FOG. SATELLITE CONTINUING TO SHOW A
COMPLICATED/SPLIT FLOW INTO THE WESTERN PORTION OF NORTH AMERICA.
THE FLOW HAS BECOME RATHER AMPLIFIED OVER THE LAST 24 HOURS FROM THE
PACIFIC INTO THE WESTERN ATLANTIC. UPPER LOW THAT BROUGHT US LIGHT
YESTERDAY AND USHERED IN THE COLDER TEMPERATURES IS MOVING SLOWLY
SOUTHEAST. UPPER RIDGE TO OUR WEST HAS A LOT OF SHORTWAVE TROUGHS
EMBEDDED IN IT.
JET LEVEL...MODELS DO NOT HAVE WEAK JET AXIS BEHIND UPPER SYSTEM FAR
ENOUGH SOUTH AND WEST. MID LEVELS...THROUGH 06Z THE MODELS ARE NOT
FAR ENOUGH SOUTH AND STRONG ENOUGH WITH THE SYSTEM DIGGING ALONG
THE WEST COAST OF CALIFORNIA. MODELS IN GENERAL WERE A LITTLE FAR
EAST WITH THE HEIGHT FIELD...ESPECIALLY OUT WEST. OVERALL THE NAM
AND ECWMF WERE DOING THE BEST. HOWEVER...MODELS WERE NOT QUITE
COLD ENOUGH ALOFT ON TOP OF US AND TO THE NORTH. LOW LEVELS...NAM AND
ECMWF WERE DOING BEST ON THE LOW LEVEL THERMAL AND WIND FIELD.
NAM LOOKS TO BE AFFECTED BY WHERE IT THINGS THE SNOW COVER. ALSO
MODEL DIFFERENCES IN HOW THEY HANDLE LOW LEVEL MOISTURE AND HOW FAR
EAST THEY PUSH THE WARM AIR. THIS ALL MAKES FOR A PROBLEMATIC
TEMPERATURE FORECAST...ESPECIALLY ON WEDNESDAY AND THURSDAY.
TODAY/TONIGHT...AM A LITTLE CONCERNED THAT THE MODELS MAY BE MOVING
THE UPPER LOW TO OUR NORTHEAST TOO FAST...SUPPORTED SOME BY THE
UPPER AIR ANALYSIS. ALL THE MODELS WANT TO MOVE IT THE SAME.
HOWEVER...STRONG RIDGE BEHIND THE SYSTEM AND ALSO IN FRONT OF IT.
SO BELIEVE MODELS WILL BE A LITTLE WARM TODAY. ALSO WEAK JET BEHIND
THIS UPPER SYSTEM MAY END UP CREATING SOME CLOUD COVER. ALSO MIXING
WILL BE LIMITED DUE TO THE LIGHT WIND FIELD DUE TO THE SURFACE
RIDGE PUSHING IN. ALSO CONSIDERING THE COLD START IN SOME PLACES...
WILL BE GOING TOWARD THE COOLER GUIDANCE.
ALSO A LOT OF MID AND ESPECIALLY LOW LEVEL MOISTURE IS TRAPPED/BANKED
UP ALONG THE HIGHER TERRAIN OF THE WESTERN HIGH PLAINS TO OUR
SOUTHEAST. THE NAM AND TO A LESSER EXTENT THE GFS CAPTURE THIS.
BOTH OF THEM THEN SURGE THE MOISTURE NORTH AFTER 00Z...AND ARE VERY
CLOSE TO WHERE THEY PUT THE AXIS OF HIGH BOUNDARY LAYER RH. WENT
CLOSER TO THE NAM DUE TO THE BETTER WIND/PRESSURE FIELD. DEFINITELY
WILL HAVE STRATUS BUT BELIEVE FOG WILL MOVE IN ESPECIALLY IN THE
WEST WHERE I INCREASED THE COVERAGE OF THE FOG.
WEDNESDAY/WEDNESDAY NIGHT...FUNCTION OF HOW WARM DOES IT GET WILL
DEPEND ON THE CLOUD COVER. MODELS VERY SIMILAR IN HANDLING THE
STRATUS/HIGH BLYR RH FIELD DURING THE DAY WITH THE SOUTHERN AND
EASTERN COUNTIES POSSIBLY GETTING SOCKED IN THROUGH MOST OF THE
DAY. SOME HIGH CLOUDS WILL ALSO BE AROUND. WESTERN LOCATIONS...
ESPECIALLY THE NORTHWEST WILL SEE THE MOST SUN. WILL PROBABLY HAVE
A TIGHT GRADIENT IN TEMPERATURE. WILL DEFINITELY GO COOLER WHERE
EXPECT MORE CLOUDS. MINS WILL STAY UP DUE TO WHERE THERE IS CLOUD
COVER IN THE EAST. WEST WINDS LOOK TO PUSH INTO THE WESTERN HALF TO
KEEP THE CLOUDS/FOG OUT. LOOKS LIKE THERE COULD BE FOG BUT A LITTLE
MORE IFFY ON THE LOCATION SO WILL LEAVE IT OUT FOR NOW.
THURSDAY/THURSDAY NIGHT...WEST NORTHWEST FLOW ALOFT IN PLACE OVER
THE AREA. MODELS DIFFER A LOT ON THEIR WIND FIELD AND DIFFER ON HOW
FAR EAST THEY PUSH A WEAK SURFACE TROUGH THROUGH. LOCATIONS TO THE
WEST OF THE TROUGH...EVEN THOUGH THERE MAY NOT BE A STRONG
DOWNSLOPE COMPONENT...LOOK TO HAVE MORE SUN. HOWEVER...HIGHER LOW
LEVEL MOISTURE WILL REMAIN IN PLACE TO THE EAST OF THIS BOUNDARY
AND THE CLOUDS WILL HAMPER THE WARMING. WILL AGAIN WILL HAVE A TIGHT
WEST TO EAST GRADIENT ON TEMPERATURES. VERY PROBLEMATIC FORECAST
SINCE ANY SUBTLE CHANGES IN BOUNDARY POSITION AND WIND DIRECTION.
THANKS TO ALL FOR COLLABORATION.
BULLER
AVIATION
425 AM MST TUE FEB 9 2010
VFR CONDITIONS WILL CONTINUE THROUGH THE EVENING HOURS AT THE
GLD AND MCK TAF SITES AS HIGH PRESSURE CONTINUES TO PERSIST THROUGH
THE DAY. FOG/LOW STRATUS WILL BEGIN TO DEVELOP OVER GLD AFTER 10Z
TONIGHT. LIFR CONDITIONS MAY BE POSSIBLE BY 12Z...BUT I HAVE KEPT
THE FORECAST IFR OR NOW SINCE THERE ARE STILL SOME UNCERTAINTIES IN
REGARDS TO LOW LEVEL MOISTURE ADVECTING IN FROM THE SOUTHWEST. LOW
STRATUS WILL LIKELY HOLD OUT OF THE MCK TERMINAL AREA THROUGH THE
TAF PERIOD...ALTHOUGH MVFR CEILINGS ARE POSSIBLE TOWARDS THE END OF
THE TAF PERIOD. WIND SPEEDS WILL DECREASE AND TURN FROM NORTH
NORTHWEST TO SOUTH SOUTHEAST WITH THE RETURN FLOW AROUND THE HIGH
PRESSURE CENTER THIS AFTERNOON AND EVENING. WINDS WILL BEGIN TO
TURN TO THE SOUTH SOUTHWEST AFTER MIDNIGHT OVER GLD.
DJR
GLD WATCHES/WARNINGS/ADVISORIES
KS...NONE.
NE...NONE.
CO...NONE.
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