FXUS63 KAPX 141422
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1022 AM EDT SUN MAR 14 2010
.SYNOPSIS.../ISSUED AT 323 AM/
LOW PRESSURE OFF THE MID-ATLANTIC COAST WILL GRADUALLY LESSEN ITS
INFLUENCE OVER THE REGION TODAY AND TONIGHT...WITH CLEARING SKIES
AND DIMINISHING BREEZES. BALMY HIGH PRESSURE WILL BUILD IN THIS
WEEK...DELIVERING ANOTHER EXTENDED STRETCH OF BEAUTIFUL SPRING WX
AND MUCH WARMER THAN NORMAL TEMPS. THE NEXT CHANCE OF APPRECIABLE
PRECIPITATION WILL NOT ARRIVE UNTIL NEXT WEEKEND. A STRONG COLORADO
LOW IS EXPECTED TO BRING THE RECENT ENJOYABLE WX TO AN ABRUPT END.
JH
&&
.SHORT TERM.../ISSUED AT 1022 AM/...THIS AFTERNOON
GOING FCST LOOKS PRETTY GOOD HEADING THRU THE AFTN...WITH MAIN FOCUS
CLOUD COVER/TEMPS/PRECIP CHANCES. MID MORNING QUICK ANALYSIS SHOWS
EXPANSIVE MID LEVEL CLOSED LOW MEANDERING OVR THE MID ATLANTIC
STATES...WITH ELONGATED TROWAL FEATURE/PERSISTENT UPGLIDE AND
MOISTURE ADVECTION SUPPORTING A RATHER LARGE AXIS OF RAIN ACRS MUCH
OF SOUTHEAST ONTARIO/SOUTHERN QUEBEC. REMNANTS OF THIS HAVE BEEN
SCRAPING FAR SOUTHEAST PORTIONS OF THE CWA ALONG THE LAKE HURON
COAST...POSSIBLY HELPED ALONG (SIMILAR TO YESTERDAY) BY LOCALIZED
LOW LEVEL JET ENHANCEMENT ABOVE STABLE MARINE LAYER ACRS THE
LAKE...ALSO LIKELY ACTING TO HELP LOWER CEILINGS AS SAID STRONGER
FLOW BANKS UP ACRS THE HIGHER TERRAIN. MEANWHILE...INFLUX OF
PRONOUNCED DRIER AIR AT THE SFC (DEWPOINTS FALLING OFF INTO THE
LOW/MID 20S IN SPOTS) HAS HELPED TO SIGNIFICANTLY CUT DOWN ON
DRIZZLE POTENTIAL THAT EARLIER REARED ITS HEAD OVR THE HIGH SPOTS.
FOR THE REMAINDER OF THE DAY...APPEARS OVERALL CLOUDY CONDITIONS
WILL REMAIN INTACT ACRS MUCH OF THE CWA AS LOW LEVEL (900-800MB) RH
PLUME CONTINUES TO SLOWLY PIVOT WESTWARD...THOUGH UNDOUBTEDLY WE
WILL EVENTUALLY SEE SOME BREAKS OPEN UP VIA PERSISTENT DOWNSLOPE
FLOW INTO NORTHWEST LOWER. MEANWHILE...EASTERN UPR IS A PESKY
MESS...AS INITIAL THOUGHTS OF MAINLY CLEAR CONDITIONS UP THAT WAY
NOT WORKING OUT WELL JUST YET...AS THICK MID/HIGH LEVEL CLOUD SHIELD
HAS TAKEN OVER. ALSO...PER RECENT VISIBLE SATELLITE TRENDS...LOW
LEVEL RH PLUME RAPID PIVOTING WESTWARD ACRS SOUTHERN ONTARIO...AN IN
LINE WITH INCOMING 12Z NAM...FEEL THAT MORE CLOUDY CONDITIONS MAY
END UP PREVAILING. AS SUCH...TEMPS RATHER TRICKY FOR THE AFTN...BUT
WILL LOWER READINGS ACRS THE NORTH WHERE LOWER CLOUDS MAY CAUSE
ISSUES INTO THE AFTN...WHILE GOING READINGS MAINLY MID 40S SOUTH
LOOK JUST FINE. WITH THAT SAID...OF COURSE ANY ADDED SUN WILL QUICK
WRECK THE TEMP FCST. AS FAR AS PRECIP...APPEARS THE MAJORITY OF RAIN
IS NOW DONE WITH WANING FORCING...THOUGH MAY STILL SEE SOME SPITS OF
LIGHT RAIN/DRIZZLE ACRS THE SOUTHEAST INTO LATE AFTN. HAVE ALSO
RAISED WIND GUSTS MOST SPOTS A FEW MPH AS COOLER PLUME OF H85 TEMPS
ROTATES NORTH INTO THE AFTN...SUPPORTING A STEEPENING OF 1000-850MB
LAPSE RATES HELPING TAP INTO QUITE GUSTY FLOW JUST OFF THE DECK.
LAWRENCE
&&
.LONG TERM.../ISSUED AT 323 AM/...SUNDAY AND BEYOND
GENERALLY QUIET WX ON TAP. WILL STILL BE DEALING WITH CYCLONIC FLOW
AND MOISTURE BELOW 700MB IN PARTS OF NORTHERN LOWER MI TONIGHT AND
EVEN PART OF MONDAY...AS THE MID-ATLANTIC COASTAL STORM CONTINUES.
500MB RIDGING ARRIVES LATE MONDAY AND MONDAY NIGHT...IN ADVANCE OF
AN UPPER TROF DROPPING INTO MN/ND. THIS TROF WILL MOVE SSE-WARD...
WITH MOST OF THE SENSIBLE WX TO OUR WEST. THUS...CLOUDS AND TEMPS
ARE THE MAIN ISSUES.
MODELS...MODELS DIFFER AS TO HOW CLOSE A CALL THE NEXT UPPER TROF ON
TUESDAY WILL BE. THE NAM AND GFS WOULD BOTH BRING A CHANCE OF PRECIP
RATHER CLOSE TO THIS FORECAST AREA. THE 12Z ECMWF...WHICH IS
PREFERRED BY HPC...IS CONSIDERABLY FURTHER WEST...AND WOULD KEEP
PRECIP A LONG LONG WAY AWAY. IT/S GOING TO BE A DRY FORECAST EITHER
WAY (FOR NOW)...BUT WE/LL SEE HOW MODEL TRENDS EVOLVE.
TONIGHT...AS MENTIONED ABOVE...MOISTURE AND CYCLONICALLY CURVED FLOW
WILL CONTINUE TO BE A NUISANCE. SOMEWHAT DRIER AIR WILL EVENTUALLY
BE ENTRAINED INTO A GOOD CHUNK OF NORTHERN LOWER MI...ESPECIALLY
AFTER MIDNIGHT. WARM ADVECTION (WITHOUT MOIST ADVECTION TO ACCOMPANY
IT) WILL LOWER RH LEVELS AND START TO BREAK UP THE CLOUDS IN NW AND
PARTS OF N CENTRAL LOWER MI. HOWEVER...NE LOWER MI (ESPECIALLY FROM
APN SOUTHWARD) WILL REMAIN CLOUDY. MEANWHILE...EASTERN UPPER MI WILL
REMAIN MOSTLY CLEAR. MIN TEMPS IN THE 30S.
MONDAY...THE SE WILL STILL HAVE CLOUDS IN THE MORNING. BUT THE
IMPENDING ARRIVAL OF A SHARP 500MB RIDGE AXIS...AND DIMINISHING OF
LOW LEVEL CYCLONIC CURVATURE...WILL FINALLY BUT THE KIBOSH ON THAT
AS THE DAY PROGRESSES. WE ARE STILL ON TAP FOR A MAINLY SUNNY DAY
ELSEWHERE. MAX TEMPS WILL BE IN THE 50S...A BIT COOLER WHERE THE
SYNOPTIC NORTH SURFACE WINDS ARE ONSHORE.
MONDAY NIGHT/TUESDAY...THE BROAD HIGH PRESSURE ANCHORED TO OUR WEST
AND NORTH WILL FINALLY START TO BUILD SOUTH TOWARD SUPERIOR BY LATE
TUESDAY. BUT OVER TOP OF THAT...AN UPPER TROF WILL BE DIGGING INTO
THE N CENTRAL STATES AND/OR WESTERN LAKES. AS MENTIONED ABOVE...THE
MODELS STILL DIFFER GREATLY AS TO WHERE THIS ENERGY WILL DIG. THE
ECMWF HAS BEEN BOTH THE MOST CONSISTENT AND THE FURTHEST WEST
SOLUTION...CLOSING OFF A 500MB LOW OVER IOWA LATE TUESDAY...WITH
ONLY A WEAK SHORTWAVE OVER SUPERIOR. THIS WILL FAVOR SOME PATCHY MID
AND HIGH CLOUDS INTO NW LOWER AND EASTERN UPPER MI DURING THE DAY ON
TUESDAY. STILL NOT ENOUGH ENOUGH TO INTERFERE WITH A PARTLY SUNNY
FORECAST YET...THOUGH EASTERN UPPER MAY PERHAPS EDGE TOWARD MOSTLY
CLOUDY BY THE END OF THE DAY. THIS AFTER A MOSTLY CLEAR MONDAY
NIGHT...WITH MIN TEMPS IN THE MID 20S TO LOWER 30S. MAX TEMPS
TUESDAY NEAR 50 TO THE MID 50S.
JZ
REST OF THE FORECAST...FLOW TURNS WNW WITH HEIGHT FALLS OVER ERN
CANADA WED. COLD FRONT GRADUALLY SINKS S WED-THU WITH WARM
SECTOR/RETURN FLOW DEVELOPING. +1 STANDARD DEVIATION (SD) WARMTH
EXPECTED THU AS THERMAL RIDGE SURGES LOW PRES MOVING EWD ALONG COLD
FRONT. ECMWF/GGEM CONTINUE THE WARMEST OFFERING MID 60S...BUT EVEN
THE MORE CONSERVATIVE GFS AND ITS ENSEMBLE MEAN SUPPORT MAX TEMPS
AROUND 60F. CPC TOOLS SHOW THAT GFS HAS VERIFIED 2-4 DEG TOO COOL
OVER THE PAST MONTH. NUDGED TEMPS UP AND BELIEVE WE'LL NEED TO GO
MORE. OVERALL BEAUTIFUL STRETCH OF SPRING WX CONTINUES. THIS COULD
END FRI...BUT UNSURE. THE ECMWF CONTINUES THE MOST POTENT W/ HEIGHT
FALLS OVR ERN CANADA. THE GGEM IS NOW ON BOARD. THIS SCENARIO WOULD
DROP COLD FRONT INTO THE FCST AREA. FRI COULD STILL SNEAK IN VERY
WARM. DETERMINISTIC MODELS AND ENSEMBLES IN GOOD AGREEMENT ON TROF
APPROACHING THE PLAINS FRI. LOW PRES WILL DEVELOP OVER COLORADO.
MAIN ? HEADING INTO SAT: WILL COLD FRONT BECOME STATIONARY OR LIFT
BACK NWD WITH APPROACH OF THE POTENT LOW. INTENSITY OF LOW SUGGESTS
POSSIBLE GALES ON THE LAKES.
PAST SEVERAL CYCLES OF GFS ENSEMBLES CONTINUE TO ADVERTISE A MAJOR
PATTERN CHANGE FOR NOAM AND IT'S LOOKING MUCH COLDER HERE BEGINNING
MON 3/21. PERSISTENT +2 STANDARD DEVIATION (SD) HEIGHT ANOMALY /H558
JAMES BAY/ OVER ERN CANADA WILL BREAK DOWN AS RIDGE BUILDS OVER AK.
THIS WILL INDUCE HEIGHT FALLS OVER CANADA...ALLOWING THE POLAR
VORTEX TO DROP INTO ITS CLIMO POSITION NEAR HUDSON BAY. BY 3/21...-1
SD HEIGHT ANOMALY IS FCST OVER THE GREAT LAKES.
JH
&&
.MARINE.../ISSUED AT 323 AM/
IN DEFERENCE TO AN EARLY THAW AND THE UPCOMING OPENING OF THE SAULT
LOCKS...NEARSHORE FORECASTS FOR ALL NORTHERN MI WATERS WILL RESUME
THIS MORNING.
WITH THAT IN MIND...A NUMBER OF SMALL CRAFT ADVISORIES NEED TO BE
HOISTED. BLUSTERY E/NE WINDS CONTINUE...NORTH OF AN ELONGATING LOW
PRESSURE AREA IN THE NORTHERN OHIO VALLEY. WINDS WILL TEND TO SLOWLY
DIMINISH TODAY INTO TONIGHT...BUT RESIDUAL WAVE ACTION WILL LINGER.
ON THE LAKE MI SIDE...ADVISORIES SOUTH OF SLEEPING BEAR WILL BE
EXTENDED THRU LATE AFTERNOON. LAKE HURON SOUTH OF BRIDGE WILL ALSO
NEED ADVISORIES...THRU THIS EVENING DOWN TO PRESQUE ISLE LT...THRU
TONIGHT SOUTH OF THERE.
JZ
&&
.AVIATION.../ISSUED AT 650 AM/...VALID FOR 12Z TAFS
MOIST EAST TO NORTHEAST LOW LEVEL FLOW WILL CONTINUE TO PROVIDE
CLOUDY SKIES THRU THIS EVENING AT THE TAF SITES...THOUGH VFR CIGS
ARE ANTICIPATED AT THE TAF SITES. SOME RAIN WILL BE JUST SOUTH OF
APN THIS MORNING...BUT ONLY A FEW DROPS AT MOST ARE EXPECTED AT THE
FIELD. THE WINDS WILL REMAIN RATHER BLUSTERY...AND LLWS WILL BE
ISSUE AT TIMES AT THE TAF SITES...ESPECIALLY THIS EVENING. PARTIAL
CLEARING WILL WORK IN LATE TONIGHT.
JZ
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ345-
346.
LH...SMALL CRAFT ADVISORY UNTIL 5 AM EDT MONDAY FOR LHZ348-349.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LHZ347.
LS...NONE.
&&
$$
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