Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/26/14
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
803 PM MST TUE FEB 25 2014
.UPDATE...
ISSUED AT 803 PM MST TUE FEB 25 2014
SNOTELS IN THE NORTHERN MOUNTAINS INDICATED ACCUMULATIONS HAD
ENDED AT MOST LOCATIONS AND ONLY BUFFALO PARK HAD PICKED UP ANY
MEASURABLE ACCUMULATION IN THE PAST COUPLE OF HOURS. SATELLITE
INDICATED THAT THE TROUGH AXIS HAD EXITED THE ADVISORY AREA.
CONSEQUENTLY...CONFIDENT SHORT RANGE MODELS ARE CORRECT IN
PRODUCING LITTLE TO NO ADDITIONAL SNOWFALL IN THE ELKHEAD AND PARK
RANGES. THEREFORE...WENT AHEAD AND CANCELLED THE WINTER WEATHER
ADVISORY WHICH WAS IN EFFECT FOR THE AREA THROUGH WEDNESDAY
MORNING.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 252 PM MST TUE FEB 25 2014
SHORT TERM FORECAST THROUGH THIS EVENING IS BASED ON RAP MODEL TRENDS
THAT SNOW WILL EXPAND SOUTHWARD OVER ROUTT COUNTY EARLY THIS
AFTERNOON. AS OF 21Z...STEAMBOAT LAKE WEB CAM INDICATE THAT SNOW
HAS REACHED HAHNS PEAK VICINITY...BUT NO MOUNTAIN TOP OBSCURATION
NEAR STEAMBOAT SPRINGS. EXPECT THIS TO CHANGE WITHIN THE NEXT
COUPLE OF HOURS AS LEADING EDGE OF BAROCLINIC ZONE AND DECENT
GRADIENT NORTHWEST FLOW LEADS TO OROGRAPHIC SNOW OVER THE MT
ZIRKEL WILDERNESS AREA AND THE PARK RANGE. RAP MODEL INDICATES
RAIN/SNOW BAND MAY EXTEND AS FAR WEST AS MAYBELL AND MEEKER LATE
THIS AFTERNOON AS THE MOISTURE BAND SLIDES SOUTH AND EAST.
PRIMARY CONCERN IS THAT THE AMPLIFYING UPSTREAM RIDGE AXIS HAS
PINCHED OFF THE PACIFIC MOISTURE STREAM INTO NORTHWEST COLORADO...
THIS IS EVIDENT ON THE SATELLITE IMAGES. NOT SURE WHETHER THE
FORECASTED SNOW AMOUNTS FOR THE PARK RANGE WILL REACH THE UPPER
RANGE OF AROUND 7 INCHES...BUT RAP QPF STILL INDICATE THAT A FEW
INCHES OF SNOW REMAIN POSSIBLE. WITH SNOW OBSERVED AT RIVERTON
AND LANDER IN WEST CENTRAL WYOMING...GIVING CREDENCE THAT THE SNOW
IS ON THE WAY. LESSER AMOUNTS OF SNOW IS ANTICIPATED FOR THE FLAT
TOP MOUNTAINS AND GORE RANGE (VAIL PASS)...DO NOT THINK THAT AN
EXPANSION OF THE WINTER WEATHER ADVISORY IS NECESSARY. MOISTURE
STREAM SLIDES EAST AFTER MIDNIGHT WITH MID LEVEL DRY STABLE AIR
ADVECTING INTO NORTHWEST COLORADO...THIS WILL SHUT DOWN OROGRAPHIC
SNOW FAIRLY QUICKLY LATE TONIGHT.
FOR THE SERN HALF OF THE FORECAST AREA THROUGH TONIGHT...CLEAR AND
DRY WEATHER IS EXPECTED FOR THE NEXT 12 TO 18 HOURS.
WEST COAST RIDGE SHIFTS INLAND ON WEDNESDAY BUT BROAD ISENTROPIC
UPGLIDE WILL RESULT IN AN INCREASE OF MID/HIGH LEVEL CLOUDS FROM
THE SOUTHWEST. NAM AND GFS SHOWING HINTS OF MOUNTAIN TOP SPOTTY
SNOW WEDNESDAY AFTERNOON AND NIGHT. SOMETIMES THIS IS OVERDONE BUT
THE TREND WILL BE FOR INCREASING CLOUDS WITH CIRROSTRATUS EVOLVING
INTO ALTOSTRATUS. WITH THE INCREASED CLOUD COVER...EXPECT
RELATIVELY MILD CONDITIONS WEDNESDAY NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 252 PM MST TUE FEB 25 2014
THE FORECAST AREA COMES UNDER THE INFLUENCE OF THE SUBTROPICAL JET
THROUGH THE WEEKEND. THIS TYPICALLY BRINGS BETTER MOISTURE BUT
MILDER TEMPERATURES WITH ASSOCIATED STORMS. BREEZY TO WINDY
CONDITIONS ARE EXPECTED IN THE MTNS AND HIGH VALLEYS...INTO THE
LOWER VALLEYS WITH SHOWERS.
THURSDAY...A TRANSIENT RIDGE PASSES IN THE EARLY AFTERNOON WITH
DEEPENING MOISTURE IN SW FLOW. 700MB SPECIFIC HUMIDITIES CLIMB TO
4 G/KG IN THE AFTERNOON. THERE IS SOME MODEL DISAGREEMENT ON
TEMPERATURES AND SNOW LEVELS. A COMPROMISE PUTS THE SNOW LEVELS
AROUND 7500FT/8500FT NORTH/SOUTH. THE DEEPEST MOISTURE IS IN THE
SOUTHERN-CENTRAL MTNS. MARGINAL INSTABILITY PRODUCES AREAS OF
STRONGER SHOWERS AND BRIEFLY LOWER SNOW LEVELS.
THURSDAY NIGHT...THE BEST FORCING OCCURS AS THE SUBTROPICAL JET
PUSHES INTO THE SOUTH THEN LIFTS INTO THE CENTRAL ZONES. SNOW
LEVELS LOWER INTO THE NORTHERN VALLEYS...TO 7500FT SOUTH.
FRIDAY IS A BRIEF BREAK UNDER AS A LOCAL RIDGE IS AMPLIFIED AHEAD
OF THE NEXT STRONG STORM BRINGING WARM ADVECTION. MOISTURE REMAINS
AT 4 G/KG SO SHOWERS INCREASE INTO THE AFTERNOON.
FRIDAY NIGHT-SATURDAY NIGHT...THE NEXT SUBTROPICAL JET STREAK LIFTS
THE EASTERN UTAH FRIDAY NIGHT THEN ACROSS WESTERN COLORADO ON
SATURDAY. AGAIN THERE IS A CONVECTIVE COMPONENT FRIDAY NIGHT INTO
SATURDAY. THERE IS AGAIN A CONVECTIVE COMPONENT TO THIS STORM.
SNOWFALL WILL FAVOR THE SOUTHERN AND CENTRAL MTNS. SNOW LEVELS
AROUND 7000FT. SATURDAY NIGHT IS TROUGH PASSAGE WITH NW FLOW
DEVELOPING. SNOW LEVEL DROPS TO AROUND 5000FT BUT WILL FAVOR THE
NW-FACING SLOPES OF THE COLORADO MTNS.
SUNDAY-TUESDAY...ARE NOW A FLAT ZONAL FLOW WITH THE POLAR FRONT
JET SETTLING INTO WYOMING THEN RAKING THE NORTH ON MONDAY. EXPECT
COOLER TEMPERATURES THROUGH THESE PERIODS WITH THE BEST SNOWFALL
FAVORING THE NORTHERN MTNS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 252 PM MST TUE FEB 25 2014
VFR PREVAILS AT ALL TAF SITES THROUGH THE PERIOD. THERE IS A 10 TO 20
PERCENT CHANCE OF -SN AT KASE AND KEGE BETWEEN 00Z AND 12Z
TONIGHT.
WIDESPREAD LIGHT SNOW IS EXPECTED EAST OF A LINE FROM DWX-KSBS-10E
KEGE-10E KASE FROM 20Z THIS AFTERNOON THROUGH 06Z THIS EVENING.
EXPECT MOUNTAIN OBSCURATIONS WITH LOW CIGS/VIS FROM LIGHT SNOW AND
FOG. SLOW IMPROVEMENT IS EXPECTED AFTER 06Z WITH NO MOUNTAIN
OBSCURATIONS AFTER 15Z.
MID/HIGH LEVEL CLOUDS INCREASE ON WEDNESDAY WITH ISOLATED MOUNTAIN
TOP FLURRIES. THIS SHOULD HAVE NO IMPACT AT MOUNTAIN AIRPORT
SITES.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...NL
SHORT TERM...PF
LONG TERM...JOE
AVIATION...PF
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1025 AM MST MON FEB 24 2014
.UPDATE...
&&
.SHORT TERM...FOG HAS BEEN STEADILY DISSIPATING ACROSS THE
NORTHEAST PLAINS...WITH INCREASED VISIBILITIES. STILL A WEAK
CYCLONE NORTH OF DENVER KEEPING LOW CLOUDS AND FOG IN AN AREA FROM
NORTH OF BOULDER TO FORT COLLINS EASTWARD ACROSS CENTRAL WELD AND
MORGAN COUNTIES. VISIBILITIES IN THIS AREA AROUND A MILE. ALLOWED
THE DENSE FOG ADVISORY TO EXPIRE AT 9AM. FOG WILL GRADUALLY
DISSIPATE THROUGH THE MORNING AS WEST NORTHWEST FLOW ALOFT MIXES
TO THE SURFACE WITH GUSTY WINDS SPREADING OFF THE FOOTHILLS.
LATEST MODELS SHOW THE NEXT FRONTAL SURGE MOVING ACROSS THE
PLAINS AFTER 20Z...REACHING DENVER AROUND 23Z WITH A SHIFT IN THE
WINDS TO THE NORTHEAST. FRONT LOOKS TO BE NEAR CASPER AT THIS
TIME. CURRENT FORECASTS HAVE SIMILAR THINKING THOUGH MAY DELAY THE
WIND SHIFT AN HOUR OR TWO. LOW CLOUDS AND STRATUS LOOK TO DEVELOP
AROUND 00Z. CHANCE FOR SNOW ACROSS THE MOUNTAINS THIS EVENING WITH
APPROACHING TROUGH AND LIFT. WON`T CHANGE MUCH TO ONGOING
FORECASTS AT THIS TIME. WILL BOOST TEMPERATURES A BIT ACROSS THE
DENVER AREA BASED ON CURRENT READINGS.
.AVIATION...WESTERLY WINDS OFF FOOTHILLS HAVE PUSHED ACROSS THE
DENVER AREA WITH GUSTS TO 26 KTS. LATEST RAP AND HRRR SHOW THE
WINDS SHIFTING TO THE NORTHWEST AT 18Z. MAY DELAY THIS WIND SHIFT
AN HOUR BASED ON CURRENT CONDITIONS. OTHERWISE CURRENT TAF TRENDS
SEEM ON TRACK. FRONT LOOKS TO MOVE ACROSS THE DENVER AREA AROUND
23Z...WILL DELAY THIS WIND SHIFT AN HOUR. IFR CONDITIONS TO
DEVELOP BY 01Z BEHIND THE FRONT WITH SNOW POSSIBLE LATE TUESDAY
MORNING...CONTINUING THROUGH THE AFTERNOON. AT THIS TIME...IT
LOOKS LIKE AROUND AN INCH OF ACCUMULATION BY TUESDAY EVENING.
&&
.PREV DISCUSSION... /ISSUED 400 AM MST MON FEB 24 2014/
SHORT TERM...SHALLOW FOG/STRATUS LAYER COVERS THE PLAINS EXCEPT
FOR A LITTLE HOLE IN DOWNSLOPE OVER DOUGLAS AND ELBERT COUNTIES.
SOME SIGNS OF STIRRING IN THIS LAYER AS WINDS ON THE PLAINS
INCREASE...SURFACE VISIBILITIES HAVE STARTED TO COME UP IN SOME
AREAS THIS LAST HOUR. HOWEVER A WEAK DENVER CYCLONE REMAINS IN
PLACE WITH LIGHT WINDS IN THE SOUTH PLATTE VALLEY AND WEST TOWARD
THE FOOTHILLS. NO REAL CLEARING FROM THE WEST YET...WEST WINDS ARE
CREEPING INTO THE LOWER FOOTHILLS SOUTH OF BOULDER...BUT MAKING
LESS PROGRESS FURTHER NORTH PROBABLY DUE TO SOME HELP FROM THE
CYCLONE CIRCULATION AND THE SE GRADIENT ON THE PLAINS. ALREADY
DELAYED CLEARING IN THE DENVER AREA A COUPLE OF HOURS. EXTENDED
THE DENSE FOG ADVISORY UNTIL 9 AM...THINGS WILL PROBABLY BE BETTER
IN DENVER A COUPLE HOURS EARLIER...BUT NOT SURE THERE WILL BE MUCH
IMPROVEMENT IN FORT COLLINS/LONGMONT/GREELEY TRIANGLE.
COMPLICATED SCENARIO FOR THE REST OF THE DAY AS WELL...AND LOW
CONFIDENCE THAT THE MODELS HAVE A GOOD HANDLE ON ALL THINGS
HAPPENING NEAR THE SURFACE. PLAINS SOUTHERLIES WILL TRY TO
MAINTAIN THE CURRENT SITUATION UNDER A STRONG INVERSION. MEANWHILE
WESTERLIES IN A WEAK MOUNTAIN WAVE WILL BE TRYING TO BREAK THROUGH
THE WEST EDGE OF THE COLD AIR. STILL THINK THE WESTERLIES WILL
PUSH OFF THE FOOTHILLS...AT LEAST INTO DENVER BUT AGAIN LESS
CERTAINTY FURTHER NORTH. WE MAY WIND UP WITH TWO OR THREE AREAS OF
CHANNELED WESTERLIES WITH COLD AIR IN THE VALLEYS IN BETWEEN. THEN
A FEATURE THAT IS NOT WELL REPRESENTED IN THE MODELS NOW ACROSS
SOUTHERN WYOMING SHOULD MOVE OVER DENVER AROUND MIDDAY. THIS WILL
LIKELY BRING A SHIFT TO A MORE NW WIND DIRECTION IN THE WARMER AIR
AND BRING SLIGHT COOLING. IT MAY ALSO INITIATE A PREFRONTAL
SOUTHWESTWARD SURGE IN THE COLD AIR. THEN THE REAL FRONT WILL PUSH
SOUTH LATER IN THE AFTERNOON. THIS APPEARS TO HAVE A PRETTY GOOD
PRESSURE WAVE BUILDING UP...WE WILL NOT HAVE THE NEAR ZERO AIR
THAT IS BEHIND THE BOUNDARY NOW...BUT STILL A PRETTY STOUT LITTLE
WAVE OF WIND AND TEMPERATURE GRADIENT WILL COME THROUGH IN THE
LATE AFTERNOON AND EARLY EVENING. THEN BACK TO LIGHTER EASTERLY
WINDS BY MIDNIGHT OR SO.
TOO MUCH TO TRY TO PIN DOWN ALL THESE LITTLE DETAILS EXACTLY...BUT
EVEN THE WARM AIR SHOULD NOT BE QUITE AS WARM AS WE EXPECTED AND
THE EARLIER SURGE AND SLIGHTLY EARLIER TIMING OF THE REAL FRONT
MEANS I NEED TO TRIM TEMPERATURES FOR TODAY. I SUBTRACTED A FEW
DEGREES IN THE WARMER AIR...AND MOVED THE NORTH/SOUTH GRADIENT
SOUTHWARD AS WELL...THEN SHOWED A BIT MORE COOLING LATE IN THE
DAY. WITH THE DRY AIR ALOFT SIGNIFICANT SNOW DOES NOT LOOK
LIKELY...BUT THE STRATUS WILL RETURN WITH THE FRONT AND THERE
COULD BE SOME FLURRIES WITH IT...AT THIS POINT THE EXISTING POPS
SEEM ALRIGHT.
LONG TERM...AN UPPER LEVEL TROUGH WILL MOVE ACROSS NRN CO TUE AFTN
INTO TUE EVENING. MEANWHILE A STG CDFNT WILL MOVE ACROSS NERN CO
BY MIDDAY ENHANCING UPSLOPE FLOW. CROSS-SECTIONS SHOW DECENT
MOISTURE IN THE MTNS TUE AFTN INTO EARLY TUE EVENING WITH DECENT
OROGRAPHICS SO SHOULD SEE A PERIOD OF SNOW WITH CLOSE TO ADVISORY
AMOUNTS IN SOME AREAS. OVER NERN CO COMBINATION OF INCREASING
UPSLOPE FLOW...SOME MDT MID LVL QG ASCENT AND POTENTIAL CSI SHOULD
LEAD TO A GOOD CHANCE OF SNOW BY EARLY TUE AFTN NR THE WY-NE
BORDER WHICH WILL SPREAD SOUTHWARD ACROSS THE PLAINS BY LATE AFTN.
APPEARS SNOW SHOULD GRADUALLY END BY EARLY TUE EVENING FM NORTH TO
SOUTH AS AS UPSLOPE FLOW WEAKENS AND DRIER AIR SPREADS ACROSS.
OVERALL AMOUNTS WILL BE IN THE 1 TO 3 INCH RANGE ALTHOUGH BANDED
PCPN COULD LEAD TO SOME 2 TO 4 INCH AMOUNTS IN SOME PLACES. HIGHS
ON TUE WILL OCCUR IN THE MORNING AND THEN STEADILY DROP IN THE
AFTN AS COLDER AIR MOVES IN BEHIND COLD FNT.
FOR WED MAINLY DRY WNW FLOW ALOFT WILL BE OVER THE AREA WITH ONLY A
SLIGHT CHC OF SNOW IN THE MTNS. HIGHS SHOULD MODERATE SOME OVER
NERN CO ALTHOUGH SNOW COVER COULD ALTER READINGS IN SOME AREAS
ESPECIALLY OVER THE FAR NERN CORNER. WILL KEEP HIGHS IN THE MID TO
UPPER 40S ALONG THE FRONT RANGE WITH UPPER 30S OVER THE FAR NERN
CORNER. BY THU THE FLOW ALOFT WILL BECOME MORE WLY AS A WEAK UPPER
LEVEL TROUGH MOVES ACROSS BY THU AFTN INTO THU NIGHT. CROSS-
SECTIONS SHOW MOISTURE INCREASING OVER THE AREA WHICH SHOULD LEAD TO
A GOOD CHANCE OF SNOW IN THE MTNS. AT LOWER ELEVATIONS SFC LOW PRES
WILL EXTEND FM SCNTRL WY INTO SERN CO WITH INCREASING SELY LOW LVL
FLOW OVER NERN CO AS COLDER AIR TRIES TO BACKDOOR INTO THE FAR NERN
CORNER. AS THE WK UPPER LEVEL TROUGH MOVES ACROSS THU NIGHT THERE
COULD BE A CHC OF SNOW ESPECIALLY OVER THE FAR NERN PLAINS. HIGHS
ON THU MAY RISE INTO THE LOWER 50S NEAR DENVER HOWEVER OVER THE
FAR NERN CORNER READINGS MAY HOLD IN THE 30S.
BY FRI THE FLOW ALOFT WILL BE WLY WITH CROSS-SECTIONS SHOWING
LIMITED MOISTURE OVER THE AREA SO WILL JUST MENTION A CHC OF LIGHT
SNOW IN THE MTNS. AT LOWER ELEVATIONS BOTH THE ECMWF AND GFS SHOW A
CDFNT BACKDOORING ACROSS MOST OF NERN CO BY AFTN WITH READINGS ONLY
IN THE LOWER 30S ALONG THE WY-NE BORDER. CLOSER TO THE FOOTHILLS
TEMP FCST WILL BE MORE DIFFICULT AS SHALLOW LYR OF COLD AIR BATTLES
DOWNSLOPE WLY FLOW COMING OFF THE HIGHER TERRAIN. FOR NOW WILL KEEP
READINGS IN THE LOWER TO MID 40S OVER DENVER. AS FOR PRECIP WILL
MENTION A SLIGHT CHANCE OF SNOW ALONG THE WY-NE BORDER PUT KEEP THE
REST OF THE PLAINS DRY.
FOR SAT INTO SAT NIGHT AN UPPER LEVEL TROUGH MAY MOVE ACROSS THE
AREA IN WLY FLOW ALOFT LEADING TO A GOOD CHANCE OF SNOW IN THE
MTNS. AT LOWER ELEVATIONS THE LOW LEVEL FLOW EAST OF THE MTNS IS
FCST TO BE SELY AS COLD SFC HIGH PRES SLIDES FM THE NRN ROCKIES
INTO THE CNTRL PLAINS. IF THE FLOW IS SELY THAT WOULD KEEP THE
BEST CHC OF SNOW NR THE WY-NE BORDER. HOWEVER IF THE FLOW ENDS UP
MORE ELY THEN THAT WOULD ENHANCE PCPN CHANCES FURTHER SOUTH. FOR
NOW WILL KEEP CHC POPS NEAR THE WY-NE BORDER WITH LOWER POPS
FURTHER SOUTH. AS FOR HIGHS WILL HAVE READINGS IN THE LOWER TO MID
30S AROUND DENVER WITH ONLY LOWER TO MID 20S OVER THE FAR NERN
CORNER.
AVIATION...VISIBILITIES WILL CONTINUE TO IMPROVE OVER THE NEXT
COUPLE HOURS WITH STRATUS DRIFTING OUT OF THE DENVER AREA BY 14Z.
VFR CONDITIONS EXPECTED MOST OF THE DAY...THEN MVFR/IFR
CONDITIONS REDEVELOPING BEHIND A COLD FRONT BETWEEN 22Z AND 02Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RPK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1026 PM MST SUN FEB 23 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 300 PM MST SUN FEB 23 2014
CURRENTLY...LOW STRATUS HAS SLOWLY ERODED TO LEAVE SUNNY SKIES
ACROSS SOUTHERN COLORADO THIS AFTERNOON. TEMPERATURES HAVE BEEN
HIGHLY DEPENDENT ON WIND...WHERE ITS WESTERLY...TEMPERATURES HAVE
WARMED INTO THE 40S TO LOW 50S...WHERE ITS EASTERLY THEY HAVE
REMAINED IN THE 30S. EXPECT A COUPLE OF MORE DEGREES OF WARMING FOR
MOST AREAS...WITH THE EXCEPTION OF THE I-25 CORRIDOR...WHERE RAPID
WARM UPS ARE POSSIBLE AS WESTERLIES TRY AND MAKE IT EAST.
TONIGHT...BROAD NORTHWEST FLOW WILL ENCOMPASS THE REGION THROUGH THE
SHORT TERM. THE MAIN QUESTION WILL BE THE DEGREE OF LOW STRATUS
SLOSHING BACK WEST ACROSS THE PLAINS TONIGHT. FOLLOWED THE HRRR AND
LOCAL WRF...WHICH KEEPS STRATUS OUT ALONG THE KANSAS BORDER WITH
LITTLE PROGRESSION WEST. THE CAVEAT WILL BE HOW QUICKLY LEE TROUGH
DEVELOPS AND LOW LEVEL WESTERLY FLOW. BOTH THE HRRR AND WRF HAVE
WESTERLIES PICKING UP BY MIDNIGHT AND SHIFTING CLEAR OUT TO THE
KANSAS BORDER BY 10-11Z. THIS SHOULD ALLOW FOR RAPID CLEARING OF
ANY STRATUS OUT EAST BY DAYBREAK. IF THE LEE TROUGHING IS SLOWER TO
DEVELOP THAN MODELS PROJECT...STRATUS COULD MAKE IT MUCH FURTHER
WEST AND IMPACT THE WARMING EXPECTED BY SUNRISE. OVERNIGHT LOWS
WILL GENERALLY BE IN THE 20S ACROSS THE REGION...WITH SOME LOWER 30S
FOR THE BANANA BELT.
MONDAY...BROAD NORTHWEST FLOW ALOFT CONTINUES WITH DRY CONDITIONS
FOR SOUTHERN COLORADO. THE MAIN CONCERNS WILL BE BREEZY AFTERNOON
WINDS LEADING TO AREAS OF BLOWING DUST AND ELEVATED FIRE WEATHER
CONCERNS. STRONG MIXING BY THE AFTERNOON WILL BRING WIDESPREAD WIND
GUSTS TO NEAR 30 MPH ALONG THE LEE SLOPES...EAST INTO THE I-25
CORRIDOR. THESE GUSTY WINDS WILL LIKELY PRODUCE AREAS OF BLOWING
DUST...ESPECIALLY IN DUST PRONE AREAS SOUTH AND NORTH OF
PUEBLO...CREATING HAZARDOUS DRIVING CONDITIONS. IN
ADDITION...HUMIDITY VALUES ARE EXPECTED TO FALL INTO THE 10-15
PERCENT RANGE...AND WHEN COMBINED WITH THE GUSTY WINDS...WILL
PRODUCE DANGEROUS FIRE WEATHER CONDITIONS...PARTICULARLY ALONG THE
SOUTHERN I-25 CORRIDOR. EXPECT THE MIXING TO HELP BOOST
TEMPERATURES FOR TOMORROW WITH HIGHS TOPPING OUT IN THE LOWER TO MID
60S FOR THE LOWER ELEVATIONS. MOZLEY
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 300 PM MST SUN FEB 23 2014
...ACTIVE WX PATTERN AS PACIFIC STORMS BEGIN TO AFFECT THE REGION...
MON NITE-INTO WED...
CANADIAN HIGH PRESSURE WILL AFFECT THE HI PLAINS DURING THIS TIME
PERIOD WITH PERSISTENT UPSLOPE FLOW OVER THE PLAINS. A SHORTWAVE
ALOFT IN THE NW FLOW WILL MOVE ACROSS TUE
AFTERNOON/EVENING...AND THIS DISTURBANCE WILL BRING A CHANCE OF
RAIN AND SNOW TO THE PLAINS. FOR NOW PAINTED POPS IN THE HIGH
ISOLATED/LOW END SCATTERED CATEGORY. WITH THE MOIST UPSLOPE FLOW
EXPECT AN EXTENDED PERIOD OF CLOUDINESS TO AFFECT THE PLAINS. BY
LATER WED...SFC FLOW WILL TRANSITION TO SOUTHERLY AND THIS
SHOULD DECREASE THE CLOUDINESS. THE ONLY POSSIBLE EXCEPTION WILL
BE THE COS AREA WHERE THE SOUTHERLY FLOW MAY KEEP THE CLOUDS IN
PLACE UNTIL LATE MORNING. PERSISTENT SNOW SHOWERS WILL BE POSSIBLE
ACROSS THE C MTNS FROM MON NITE-EARLY WED
THURSDAY...
THE FIRST IN A SERIES OF PACIFIC WEATHER SYSTEMS WILL BEGIN TO
AFFECT THE REGION. VALLEY RAIN SHOWERS AND SNOW IN THE MTNS WILL
AFFECT THE CONTDVD BY THU LATE MORNING OR EARLY AFTERNOON AND
INCREASE THU AFTERNOON AND NITE. GIVEN THE QUALITY
MOISTURE...INSTABILITY...UPSLOPE FLOW AND FORCING...WE WILL LIKELY
SEE SNOWFALL AMOUNTS REQUIRING HILITES (WINTER STORM WARNING?) FOR
THE CONTDVD.
LATE THU NITE INTO FRIDAY...
UPSLOPE FLOW DEVELOPS ON THE PLAINS AND WE WILL SEE COOLER
WX...CLOUDINESS AND A CHANCE OF SOME PRECIP RETURNING TO THE LOWER
ELEVATIONS.
WEEKEND...
FRI NITE INTO EARLY SATURDAY A BRIEF RIDGE WILL BUILD ALOFT
DECREASING THE CLOUDS AND ENDING THE PRECIP...BUT ANOTHER STRONGER
PACIFIC STORM WILL BE QUICKLY MOVING IN. AS THIS PACIFIC STORM MOVES
TOWARDS THE CONTDVD...ANOTHER REINFORCING CANADIAN HIGH PRESSURE
SYSTEM WILL BE MOVING DOWN THE PLAINS...AND WILL BE AFFECTING THE
LOWER ELEVATIONS BY LATER SATURDAY MORNING. SNOW WILL DEVELOP ONCE
AGAIN OVER THE MTNS DURING THE DAY SATURDAY WITH PRECIP DEVELOPING
ON THE PLAINS LATE SAT AFTERNOON/EVENING. GUIDANCE AT THIS TIME IS
FAVORING THE PALMER DVD BUT I WOULD NOT BE TOO SURPRISED IF ALL OF
THE PLAINS RECEIVE SOME PRECIP SAT NITE INTO SUNDAY AS THE MIDLVL
TROUGH MOVES OVER THE REGION. OVERALL METEOROLOGICAL CONDITIONS
FOR THIS WEEKENDS STORM LOOK PRETTY GOOD GIVEN THAT THE COLD AIR
WILL ALREADY BE IN PLACE AS THE DYNAMICS MOVE OVER THE REGION. FOR
NOW I GOT TEMPS IN THE 30S AND 40S FOR THE WEEKEND WITH SLIGHT/LOW
END SCT POPS FOR THE AREA. I WOULD NOT BE TOO SURPRISED IF THE
TEMPS ARE LOWERED AND THE POPS ARE INCREASED AS WE GET CLOSER TO
THIS EVENT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1019 PM MST SUN FEB 23 2014
MVFR TO IFR STRATUS IS WORKING ITS WAY WESTWARD ACROSS SOUTHEAST
CO TONIGHT. FORECAST MODELS TYPICALLY HAVE A TOUGH TIME
FORECASTING WESTWARD EXTENT AND BASED ON TRENDS IN LATEST SATELLITE FOG
PRODUCT AND IN RAP13...HAVE PUT A TEMPO GROUP FOR BKN010 AT
KCOS...AND A PREVAILING MVFR CIG (BKN015) AT KPUB. ITS POSSIBLE
STRATUS DECK COULD STALL OUT TO THE EAST OF THE KCOS
TERMINAL...AND GIVEN THE UNCERTAINTY DECIDED TO KEEP IT IN A TEMPO
GROUP FOR NOW. ONCE WINDS SHIFT OUT OF THE NORTH...THAT SHOULD
ERODE IT AWAY FROM KCOS FAIRLY EARLY MONDAY MORNING (10Z)...AND
AN HOUR OR SO LATER (11Z) AT KPUB. GUSTY WEST TO NORTHWEST WINDS
WILL KICK IN AT KPUB AROUND 18Z ON MONDAY WITH WINDS REMAINING A
LITTLE LIGHTER FOR KCOS. A COLD FRONT WILL MOVE THROUGH SE CO
MONDAY EVENING AND HAVE IT TIMED TO PASS THROUGH KCOS AROUND 04Z
AND KPUB AROUND 05Z BRINGING A PERIOD OF GUSTY NORTHEAST WINDS.
KALS WILL REMAIN VFR WITH WIND SPEEDS 10 KTS OR LESS THROUGH THE
NEXT 24 HOURS. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM 10 AM MST MONDAY THROUGH MONDAY
AFTERNOON FOR COZ228>230.
&&
$$
SHORT TERM...MOZLEY
LONG TERM...HODANISH
AVIATION...KT
AREA FORECAST DISCUSSION
NWS ALBANY NY
424 PM EST MON FEB 24 2014
.SYNOPSIS...
AN ARCTIC AIR MASS WILL BE IN PLACE THIS WEEK WITH BELOW NORMAL
TEMPERATURES. A SERIES OF DISTURBANCES ASSOCIATED WITH AN UPPER
LEVEL LOW WILL PRODUCE SCATTERED SNOW SHOWERS AND FLURRIES INTO THE
MID WEEK. A CLIPPER LOW ON WEDNESDAY WILL PRODUCE MORE WIDESPREAD
SNOW SHOWERS...AS IT PASSES ACROSS THE SOUTHERN QUEBEC AND NORTHERN
NEW YORK BORDER...WITH A REINFORCING SHOT OF ARCTIC AIR.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
AS OF 423 PM EST...A BROAD H500 UPPER LEVEL LOW WILL IMPACT THE
NORTHEAST THROUGH THE WEEK WITH SEVERAL SURGES OF ARCTIC AIR. THE
UPPER LEVEL TROUGH IS AN EXTENSION OF THE POLAR VORTEX. ONE CLOSED
H500 CIRCULATION IS OVER N-CNTRL QUEBEC. ANOTHER POTENT SHORT-WAVE
MOVING S/SE IN THE TROUGH IS APPROACHING FROM NEAR ND/NW MN BASED
ON THE LATEST WV LOOP. SOME OF THE SHORT-WAVE ENERGY FROM THE
DISTURBANCE WILL BE THE CLIPPER FOR LATE TUE NIGHT INTO WED TO
IMPACT THE REGION.
CYCLONIC FLOW ALOFT WILL DOMINATE WITH SEVERAL SFC TROUGHS MOVING
THROUGH THE LONGWAVE TROUGH. ONE MOVED THROUGH THE REGION THIS
AFTERNOON WITH MAINLY DIFFUSE ACTIVITY DUE TO THE STEEP MID LEVEL
LAPSE RATES...AS H500 TEMPS ARE IN THE -35C TO -37C RANGE. THERE
WAS AN ORGANIZED BAND OF SNOW SHOWERS THAT WAS IMPACTING THE WRN
MOHAWK VALLEY THAT BROKE UP AS IT MOVED EAST.
THE LAKE EFFECT SNOW ADVISORY WAS CANCELLED FOR NRN HERKIMER
CTY...SINCE THE BEST ORGANIZED LAKE BAND LATE THIS AFTERNOON AND
TONIGHT LOOKS TO IMPACT SRN HERKIMER CTY. THE INVERSION HEIGHTS ARE
MARGINAL UPSTREAM AT KSYR/KRME/KUCA AT 6-7 KFT AGL WITH A 280-290
DEG LOW-LEVEL TRAJ. THE INSTABILITY CLASS IS CONDITIONAL TO
MODERATE WITH THE POSSIBILITY OF A LAKE BAND EXTENDING DOWNSTREAM
INTO SRN HERKIMER SUPPORTED BY THE LOCAL HIRESWRF COLUMNAR REF
PRODUCT BTWN 21Z-03Z. THE LATEST HRRR 3-KM REF PRODUCT ALSO KEYS
INTO THIS AREA. AN ADDITIONAL 2 TO 6 INCHES IS POSSIBLE FOR
PORTIONS OF SOUTHERN HERKIMER CTY...WITH TOTALS OF 3 TO 8 INCHES
MENTIONED IN THE STATEMENT. ONLY AN ADDITIONAL INCH OR TWO IS
POSSIBLE FOR THE WRN DACKS...AND MOSTLY OF THE OPEN CELLULAR SNOW
SHOWER ACTIVITY. GENERALLY...SLIGHT TO LOW CHC POPS HAVE BEEN USED
PRIOR TO MIDNIGHT NORTH AND WEST OF THE MID HUDSON VALLEY AND NW
CT...WITH THE BEST CHCS OF SNOW SHOWERS WEST OF THE HUDSON RIVER
VALLEY AFTER MIDNIGHT.
H850 TEMPS WILL BE IN THE -17C TO -20C RANGE WITH THE COLD
ADVECTION IN THE WAKE OF THE SFC TROUGH. EXPECT LOWS TO BE IN THE
UPPER SINGLE DIGITS AND TEENS FROM THE CAPITAL DISTRICT SOUTH AND
EAST...WITH SINGLE DIGITS TO A FEW BELOW ZERO READINGS /SRN DACKS/ OVER
THE NRN TIER. BRISK W/NW WINDS WILL GENERATE WIND CHILLS 10 TO 15
BELOW ZERO OVER THE SRN DACKS...AND GENERALLY 5 BELOW TO 5 ABOVE
IN MOST OTHER LOCATIONS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
TUESDAY...ANY ORGANIZED LAKE EFFECT ACTIVITY DIMINISHES DUE TO THE
LOWERING INVERSION. HOWEVER...LAKE MOISTURE WILL STILL BE
UTILIZED...AS A WEAK MID LEVEL DISTURBANCE MAY FOCUS ISOLATED TO
SCATTERED SNOW SHOWERS AGAIN DURING DURING THE MORNING INTO THE
AFTERNOON...WITH THE BETTER CHANCE OF SNOWFALL IN THE AFTERNOON
ALONG THE WRN SPINE OF THE WRN DACKS...SRN GREENS...NRN-CNTRL
TACONICS AND BERKSHIRES. THE WESTERLY UPSLOPE SNOW SHOWERS AND
FLURRIES MAY PRODUCE LIGHT SNOW AMOUNTS OF A COATING TO AN INCH OR
TWO. H850 TEMPS WILL BE RUNNING 1 TO 2 STANDARD DEVIATIONS BELOW
NORMAL ACCORDING TO THE LATEST GEFS. TEMPS WILL STILL RUN ABOUT 10
DEGREES OR SO BELOW NORMAL. OUR FORECAST FAVORS THE COLD NAM MOS
MAX TEMPS WITH TEENS OVER THE SRN DACKS. LOWER TO M20S OVER THE
REST OF THE FCST AREA...EXCEPT U20S OVER THE MID HUDSON
VALLEY...SRN TACONICS...AND NW CT.
TUE NIGHT...A CLIPPER LOW APPROACHES FROM THE NRN GREAT LAKES
REGION...AND SE ONTARIO. THIS CLIPPER WILL TAP SOME LAKE EFFECT
MOISTURE...AS THE FLOW BACKS TO SOUTHWEST. THERE IS SOME SYNOPTIC
LIFT WITH THIS SYSTEM. OROGRAPHIC AND LOW-LEVEL CONVERGENCE MAY
PROMOTE A PERIOD OF LIGHT SNOW ESPECIALLY NORTH AND WEST OF THE
CAPITAL REGION. A BURST OF LAKE EFFECT OR LAKE ENHANCED SNOWFALL
MAY OCCUR OVER THE WRN DACKS/WRN MOHAWK VALLEY AROUND MIDNIGHT AND
THEREAFTER. 1-4 INCHES OF SNOWFALL MAY BE POSSIBLE...ESPECIALLY
OVER THE WRN DACKS BY WED MORNING. WITH THE WEAK THERMAL
ADVECTION...SLIGHT OR LOW CHANCES OF SNOW SHOWERS SPREAD EASTWARD
ACROSS THE FCST AREA AFTER MIDNIGHT. LOWS WILL RANGE FROM THE
SINGLE DIGITS OVER THE NW PORTION OF THE FCST AREA TO TEENS FROM
THE MOHAWK VALLEY/CAPITAL REGION SOUTH AND EAST.
WED-WED NIGHT...THE CLIPPER MOVES N/NE OF NRN NY OVER SRN QUEBEC
BY NOON. ANOTHER LOW PRESSURE SYSTEM FORMS WELL OFF THE MID
ATLANTIC COAST. A PERIOD OF SNOW SHOWERS OR LIGHT SNOW WILL IMPACT
THE REGION DURING THE MORNING INTO THE EARLY PM AHEAD OF THE
ARCTIC FRONT. CHC POPS WERE USED FOR THE ENTIRE AREA. SNOW ACCUMS
OF A COATING TO AN INCH WILL BE POSSIBLE. ARCTIC AIR POURS BACK
INTO THE REGION WITH H850 TEMPS FALLING TO -19C TO -23C OVER THE
FCST AREA...AND THE GEFS INDICATE THESE VALUES WILL BE 2 TO 3
STANDARD DEVIATIONS BELOW NORMAL. THE STRONG COLD ADVECTION SWEEPS
THROUGH BEFORE NIGHTFALL. AFTER HIGHS IN THE TEENS AND 20S WITH
BLUSTERY CONDITIONS...LOWS WILL BE ZERO TO 5 BELOW OVER THE SRN
DACKS AND PARTS OF THE LAKE GEORGE REGION....AND SINGLE DIGITS
ELSEWHERE. UPSLOPE AND LAKE EFFECT SNOW SHOWERS WILL CONTINUE IN
THE AFTERNOON...AND THEN TAPER SNOW SHOWERS NORTH AND WEST OF THE
TRI CITIES WITH ANOTHER DISTURBANCE APPROACHING FROM THE UPPER
GREAT LAKES REGION. WIND CHILLS VALUES MAY NOT HIT ADVISORY LEVELS
WED NIGHT DUE TO A WEAKENING WIND FIELD...BUT MAY HIT ADVISORY
LEVELS OVER SOME OF THE MTN ZONES THU NIGHT/FRI MORNING.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
A SERIES OF EMBEDDED SHORTWAVES WILL MOVE ABOUT THE BASE OF A LARGE
UPPER LEVEL TROUGH THAT WILL PROVIDE CHANCES OF SOME PRECIPITATION
THROUGHOUT THE EXTENDED PERIOD. THE UPPER LEVEL FLOW PATTERN WILL
BEGIN TO SLOWLY TRANSITION INTO A ZONAL PATTERN WITH COLD AIR STILL
IN PLACE AS WE GO THE THE END OF THE EXTENDED PERIOD.
THURSDAY INTO FRIDAY...COLD NORTHWESTERLY FLOW WITH BELOW AVERAGE
TEMPERATURES WITH T850 BETWEEN -20C TO -24C AND T925 TEMPS BETWEEN
-16C AND -20C WILL BE LOCKED INTO THE REGION. A NEGATIVE TILTED
SHORTWAVE TROUGH WITHIN THE UPPER LEVEL FLOW WITH THE AXIS OVER THE
NY/CANADA BORDER WILL PROVIDE THE CHANCE OF SNOW SHOWERS ESPECIALLY
AREAS NORTH AND WEST OF THE IMMEDIATE CAPITAL REGION NEAR THE UPPER
LEVEL TROUGH AS WE GO THURSDAY NIGHT INTO FRIDAY MORNING. A STEEP
GRADIENT IN ISOBARS WILL ALSO PRODUCE GUSTY NORTHWEST WINDS
WITH GUSTS NEAR 30 MPH POSSIBLE ESPECIALLY IN THE HIGHEST TERRAIN.
TEMPERATURES ON THURSDAY WILL RANGE FROM THE LOWER 20S TO UPPER 20S
WHICH WILL FALL TO LOWER TEENS IN THE HIGH TERRAIN TO NEAR 20 IN
VALLEY LOCATIONS ON FRIDAY. LOW TEMPERATURES ON THURSDAY WILL BE
VERY COLD WITH VALUES RANGING FROM 10 BELOW TO NEAR ZERO IN THE HIGH
TERRAIN TO AROUND ZERO TO 5 ABOVE FOR THE VALLEY AREAS.
FRIDAY NIGHT THROUGH MONDAY...COLD AIR FROM CANADA WITH
NORTHWESTERLY WINDS WILL CONTINUE WITH SERIES OF UPPER LEVEL TROUGHS
CONTINUING TO MOVE WEST TO EAST ACROSS OUR AREA WITH AREAS OF WEAK
HIGH PRESSURE IN BETWEEN THE PASSING DISTURBANCES AS THE UPPER LEVEL
WAVE OSCILLATES AROUND THE LARGE UPPER LEVEL LOW IN NORTHERN QUEBEC.
THE NEXT CHANCE OF SNOW SHOWERS ACCORDING TO THE LATEST 12Z MODELS
AND NUMERICAL GUIDANCE WILL BE DURING THE DAY ON SATURDAY AS ANOTHER
WAVE OF LOW PRESSURE MOVES RIGHT OVER OUR REGION ACCORDING TO THE
LATEST TRENDS. CHANCE OF SNOW SHOWERS WILL BE IN THE FORECAST AT
THIS TIME AS THE TRACK AND INTENSITY AGREEMENT BETWEEN THE MODELS
SHOW LOW CONFIDENCE AT THIS TIME. A SURFACE HIGH PRESSURE WILL WORK
INTO THE AREA ON SUNDAY GIVING TRANQUIL WEATHER CONDITIONS. AS WE GO
INTO MONDAY...THE MODELS DO DIFFER IN OUR NEXT WEATHER SYSTEM WITH
ITS TRACK AND INTENSITY. THIS WILL HAVE TO BE MONITORED WITH FUTURE
UPDATES TO THE FORECAST. HIGH TEMPERATURES FROM SATURDAY INTO MONDAY
WILL REMAIN BELOW AVERAGE WITH TEMPERATURES RANGING FROM THE MID
TEENS TO MID 20S. LOW TEMPERATURES WILL ALSO BE VERY COLD FOR THIS
TIME OF YEAR WITH TEMPERATURE 10 BELOW ZERO TO NEAR ZERO FOR THE
LAKE GEORGE SARATOGA REGION POINTS NORTH AND WEST AND ALSO IN THE
HIGH TERRAIN OF NEW ENGLAND AND WITH LOW TEMPERATURES OF 0 TO 5 IN
THE IMMEDIATE CAPITAL REGION AND VALLEY LOCATIONS.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
SOME LAKE EFFECT/ENHANCED SNOW SHOWERS/FLURRIES MAY REACH
KGFL/KALB/KPSF AT TIMES THIS AFTERNOON. MAINLY VFR CONDITIONS ARE
EXPECTED...BUT ANY SNOW SHOWER ACTIVITY COULD PRODUCE BRIEF PERIODS
OF MVFR/IFR...ESP FOR VSBYS. THE SNOW SHOWER THREAT SHOULD END AT
KGFL THIS EVENING. THE SCATTERED SNOW SHOWER THREAT SHOULD CONTINUE
AT KALB AND KPSF THROUGH TONIGHT DUE TO THE WIND DIRECTION NEARLY
PARALLELING THE MOHAWK VALLEY AND INTO THE BERKSHIRES...OSCILLATING
NORTH AND SOUTH WITH SUBTLE WIND SHIFTS. STILL...VFR CONDITIONS
SHOULD DOMINATE ALL TAF SITES THROUGH TOMORROW MORNING OUTSIDE OF
ANY BRIEF SNOW SHOWERS.
WEST TO NORTHWEST WINDS AT 13-18 KT WITH GUSTS OF 20-30 KT ARE
EXPECTED THIS AFTERNOON. THE STRONGEST GUSTS ARE EXPECTED FROM
KALB-KPSF IN THE FAVORED W-NW FLOW. THESE BRISK WINDS WILL PERSIST
THROUGH EARLY MONDAY EVENING...BEFORE GRADUALLY DIMINISHING AFTER
05Z-08Z/TUE TO 5-10 KT. WEST WINDS SHOULD CONTINUE TOMORROW MORNING
AT AROUND 10 KT.
OUTLOOK...
TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
WEDNESDAY: MODERATE OPERATIONAL IMPACT.WINDY WITH A CHANCE OF
SHSN.
WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF SHSN.
THURSDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
&&
.HYDROLOGY...
AN ARCTIC AIR MASS WILL REMAIN ACROSS THE HYDRO SERVICE AREA FOR
THE ENTIRE WEEK WHICH WILL ALLOW ICE TO REFORM...THICKEN...AND
STRENGTHEN ON AREA RIVERS AND LAKES THROUGH THE WEEK. LIGHT
PRECIPITATION IS EXPECTED DURING THE WEEK...AND ANY THAT DOES
OCCUR WILL BE IN THE FORM OF SNOW SHOWERS OR LIGHT SNOW. NO HYDRO
IMPACTS ARE EXPECTED ON THE MAIN STEM RIVERS THE NEXT 5 DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 6 AM EST TUESDAY FOR NYZ038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...11/WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...LFM
AVIATION...NAS
HYDROLOGY...11/WASULA
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1242 PM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT WAS EXITING THE REGION EARLY THIS MORNING...
BRINGING PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND.
MAINLY DRY CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE
MOVES ACROSS. ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING
SNOWFALL FOR WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW
ENGLAND. ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1240 PM UPDATE...
DECENT COVERAGE OF STRATO CU ACROSS SNE EXCEPT FOR FAR SE MA AND
CAPE/ISLANDS. LOW AND MID LEVEL MOISTURE COMBINED WITH STEEP LOW
LEVEL LAPSE RATES RESPONSIBLE FOR THE CLOUDS. HIRES MODELS
CONTINUE TO SHOW POTENTIAL FOR A FEW SNOW SHOWERS ACROSS NORTHERN
ZONES THIS AFTERNOON ALTHOUGH LOW DEWPOINTS WILL LIMIT AREAL
COVERAGE. NEAR STEADY TEMPS WITH GUSTY WINDS.
PREVIOUS DISCUSSION...
POST FRONTAL STRATO-CU FILLING BACK IN ACROSS THE INTERIOR AS LOW
AND MID LEVEL MOISTURE FROM THE N SPILLS INTO THE REGION AND
EXPECT SCT-BKN CU TO DEVELOP IN THE COASTAL PLAIN. STEEP LOW LEVEL
LAPSE RATES AND LOW LEVEL MOISTURE SUPPORT A FEW FLURRIES OR SNOW
SHOWERS...ESPECIALLY N OF THE PIKE WHERE HRRR IS TARGETING. STRONG
COLD AIR ADVECTION WILL RESULT IN TEMPS REMAINING NEARLY STEADY OR
PERHAPS FALLING A FEW DEGREES ALONG WITH GUSTY W/NW WINDS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
NOT TOO MUCH CHANGE FROM THE DAY AS CYCLONIC CURVATURE...DECENT
SFC PRES GRADIENT AND TRAPPED MID LVL MOISTURE REMAIN IN PLAY
ACROSS THE AREA. THEREFORE..EXPECT AT LEAST SOME CLOUDS AND WINDS
TO REMAIN THROUGH THE OVERNIGHT HOURS. WHILE THIS WILL LIMIT THE
ABILITY TO RADIATE...NORMAL DIURNAL TRENDS SHOULD STILL ALLOW MINS
INTO THE LOW TEENS AND 20S. WITH WINDS OF AROUND 10 MPH STILL
POSSIBLE...THIS WOULD YIELD SOME WIND CHILLS BELOW ZERO FOR
PORTIONS OF THE INTERIOR AND IN THE SINGLE DIGITS CLOSER TO THE
SHORELINES.
TUESDAY...
A COLD AND BRISK START IS EXPECTED AS WINDS CONTINUE TO GUST UP TO
ABOUT 20 MPH AFTER SUNRISE AND MIXING SETS UP. ANOTHER ROUND OF
PARTLY CLOUDY CONDITIONS AND HIGHER SUN ANGLES SHOULD ALLOW HIGHS
TO INCREASE INTO THE MID 20S TO LOW 30S DESPITE THIS COOLER START
BUT WITH WIND CHILL VALUES IN THE TEENS TO LOW 20S. MAINLY DRIER
WX AS NOSE OF HIGH PRES BEGINS TO BUILD OVER FROM THE
SW...LIMITING THE POTENTIAL FOR MORE FLURRY ACTIVITY IN COMPARISON
TO MON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* JANUARY-LIKE TEMPERATURES THIS WEEK AND AS WE ENTER MARCH NEXT
WEEKEND
* RISK FOR ACCUMULATING SNOW WED AND AGAIN NEXT WEEKEND
* OTHERWISE MAINLY DRY CONDITIONS PREVAIL
SYNOPTIC OVERVIEW...
NOT MUCH CHANGE IN THE FORECAST FROM PREVIOUS DAYS. HIGH AMPLITUDE
NORTHERN STREAM PATTERN DEVELOPS WITH POLAR VORTEX BEING DISPLACED
SOUTHWARD INTO ONTARIO BY THU. THIS RESULTS IN A STEADY STREAM OF
ARCTIC AIR INTO SOUTHERN NEW ENGLAND THIS WEEK AND INTO NEXT
WEEKEND. THAT/S THE EASY PART OF THE FORECAST. WHAT BECOMES
DIFFICULT TO NAIL DOWN AT THIS TIME RANGE IS THE INTENSITY AND TRACK
OF ANY EAST CYCLOGENESIS...AS ARCTIC SHORT WAVES PIVOT AROUND THE
SOUTHERN BASE OF THE POLAR VORTEX. FURTHER COMPLICATING THE FORECAST
IS IF PACIFIC ENERGY UNDERCUTTING THE WESTERN RIDGE INTERACTS
/PHASING VS UNPHASED/ WITH ARCTIC SHORT WAVE TROUGHS ALONG THE EAST
COAST.
MODEL PREFERENCES AND SENSIBLE WEATHER...
WEDNESDAY...00Z DETERMINISTIC GFS AND ECMWF IN AGREEMENT ON AN
UNPHASED SOLUTION WITH NORTHERN STREAM LOW MOVING ACROSS SOUTHEAST
CANADA AND EAST COAST CYCLOGENESIS TRACKING WELL SOUTHEAST OF
40N/70W BENCHMARK. HOWEVER APPEARS THERE WILL BE ENOUGH MID LEVEL
LIFT TO INDUCE AN INVERTED SURFACE TROUGH BETWEEN THESE TWO LOWS TO
GENERATE A FEW TENTHS OF QPF OVER SOUTHERN NEW ENGLAND. THUS A LOW
TO MODERATE RISK OF A FEW FLUFFY INCHES OF SNOW...WITH HIGHEST RISK
OVER SOUTHEAST MA.
HOWEVER CAN/T COMPLETELY RULE OUT A STRONGER/PHASED SOLUTION AS
ARCTIC SHORT WAVE/PV ANOMALY THAT INDUCES EAST COAST CYCLOGENESIS
IS CURRENTLY MOVING ACROSS NORTHWEST CANADA EARLY THIS MORNING.
MODELS LIKELY NOT SAMPLING THIS PACKET OF JET ENERGY VERY WELL
GIVEN THIS IS A DATA SPARSE AREA. THUS WILL HAVE TO WAIT UNTIL
THIS FEATURE ENTERS SOUTHERN CANADA BEFORE MODELS BEGIN BETTER
SAMPLING OF THIS JET ENERGY. IF THIS SHORT WAVE TROUGH IS MORE
AMPLIFIED THAN MODELS CURRENTLY SIMULATE...A TRACK CLOSER TO THE
COAST IS PLAUSIBLE. THEREFORE ITS STILL TOO EARLY TO LOCK INTO A
SINGLE SCENARIO. HOWEVER FOR THE MOMENT WILL PLAY THE MOST LIKELY
SCENARIO...A LOW TO MODERATE RISK OF A FEW INCHES OF FLUFFY SNOW.
THURSDAY THRU SUNDAY...ANOTHER ARCTIC FRONT MOVES ACROSS THE AREA
THU OR FRI WITH GEFS AND ECENS ENSEMBLE POST FRONTAL 850 MEAN TEMPS
VARYING FROM -15C TO -20C ACROSS SOUTHERN NEW ENGLAND. THUS COLDER
THAN NORMAL TEMPS HOWEVER ANY RECORD BREAKING COLD SHOULD REMAIN
WEST OF NEW ENGLAND ACROSS THE GREAT LAKES GIVEN PROXIMITY OF COLD
AIR CORE. WILL ALSO HAVE TO WATCH FOR POTENTIAL SNOW SQUALLS ALONG
AND AHEAD OF FRONTAL BOUNDARY...AS INCREASING SUN ANGLE /SAT MAR
1ST/ AND COLD AIR ALOFT WILL YIELD STEEP LOW LEVEL LAPSE RATES.
THEN NEXT WEEKEND THE FOCUS WILL BE ON PACIFIC ENERGY MARCHING
ACROSS THE SOUTHERN STATES AND ITS POSSIBLE INTERACTION/PHASING WITH
THE NORTHERN STREAM OVER THE NORTHEAST. THE 00Z GEFS AND ECENS
ENSEMBLE MEAN ARE WELL OFFSHORE WITH ANY CYCLOGENESIS...AS WELL AS
THE 00Z GFS. THE 00Z ECMWF IS MUCH CLOSER TO THE COAST BUT ALSO
WEAKER. GIVEN THE UNCERTAINTY WILL CONTINUE WITH CHANCE POPS FOR
NEXT WEEKEND.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY NIGHT/...
HIGH CONFIDENCE. MAINLY VFR THROUGH THE PERIOD WITH OCCASIONAL
CIGS 040-080. A FEW LIGHT SNOW SHOWERS POSSIBLE THIS AFTERNOON
NORTH OF THE PIKE AND AGAIN TUE AFTERNOON. W/NW WIND GUSTS TO 25
KT THIS AFTERNOON DIMINISHING TONIGHT...THEN 20-25 KT TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
VFR ALONG WITH GUSTY WNW WINDS. THE EXCEPTION WILL BE WED WHEN WINDS
WILL BRIEFLY RELAX. HOWEVER A PERIOD OF SNOW IS POSSIBLE WED WITH
MVFR CONDITIONS. HIGHEST PROBABILITY OF SNOW AND MVFR CONDITIONS IS
ACROSS SOUTHEAST MA WED.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TUESDAY...HIGH CONFIDENCE.
W-NW WINDS WILL BE INCREASING THROUGH THE DAY TODAY WITH GUSTS
WIDESPREAD 25-30 KT EXPECTED. A FEW GUSTS MAY APPROACH GALE
FORCE...BUT THE MAJORITY SHOULD REMAIN BELOW. THESE WINDS WILL
MAINTAIN THROUGH THE OVERNIGHT HOURS TONIGHT...ONLY DIMINISHING
INTO THE MORNING HOURS FOR TUE THEN DROPPING BELOW SMALL CRAFT
THRESHOLDS BY THE LATE DAY TUE.
WITH INCREASING WINDS EXPECT SEAS TO BUILD AS WELL...REACHING
5-7FT AT TIMES MAINLY ON THE OCEAN WATERS.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
GUSTY WNW WINDS AND PERIODS OF FREEZING SPRAY ARE EXPECTED AS ARCTIC
AIR OVERSPREADS THE REGION. WINDS BRIEFLY RELAX WED AS ONE AREA OF
LOW PRES TRACKS ACROSS SOUTHEAST CANADA AND A POTENTIAL GALE CENTER
PASSES SOUTHEAST OF 40N/70W BENCHMARK. A PERIOD OF SNOW WITH REDUCED
VSBY IS LIKELY WED ESPECIALLY OVER THE WATERS SOUTHEAST OF
NANTUCKET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST TUESDAY FOR ANZ230>237-251.
SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...NOCERA/DOODY
NEAR TERM...KJC
SHORT TERM...DOODY
LONG TERM...NOCERA
AVIATION...KJC/NOCERA
MARINE...NOCERA/DOODY
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1018 AM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT WAS EXITING THE REGION EARLY THIS MORNING...
BRINGING PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND.
MAINLY DRY CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE
MOVES ACROSS. ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING
SNOWFALL FOR WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW
ENGLAND. ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1015 AM UPDATE...
POST FRONTAL STRATO-CU FILLING BACK IN ACROSS THE INTERIOR AS LOW
AND MID LEVEL MOISTURE FROM THE N SPILLS INTO THE REGION AND
EXPECT SCT-BKN CU TO DEVELOP IN THE COASTAL PLAIN. STEEP LOW
LEVEL LAPSE RATES AND LOW LEVEL MOISTURE SUPPORT A FEW FLURRIES
OR SNOW SHOWERS...ESPECIALLY N OF THE PIKE WHERE HRRR IS
TARGETING. STRONG COLD AIR ADVECTION WILL RESULT IN TEMPS
REMAINING NEARLY STEADY OR PERHAPS FALLING A FEW DEGREES ALONG
WITH GUSTY W/NW WINDS.
PREVIOUS DISCUSSION...
OTHERWISE TODAY...AFTER THE FRONT/PRECIP BAND SHIFTS
OFFSHORE...STRONG COLD ADVECTION WILL DEFINE THE WX. H85
TEMPERATURES WILL BE DECLINING FROM AN AVERAGE OF ABOUT -5C TO
ABOUT -16C BY THE OVERNIGHT HOURS TONIGHT. DRY AIR WILL ALSO BE
RAPIDLY MOVING IN WITH TIME AS WELL. THEREFORE...EXPECT HIGH TEMPS
TO OCCUR BY LATE THIS MORNING WITH COOLING EXPECTED THROUGH THE
AFTERNOON HOURS...WITH RANGES FROM THE LOW TO UPPER 30S. THE
COMBINATION OF STRONG CYCLONIC CURVATURE ALOFT WITH A SHORTWAVE
MOVING ACROSS THE AREA...STEEP SFC-H9 LAPSE RATES ON THE ORDER OF
8C/KM AND A BIT OF TRAPPED MID LVL MOISTURE BENEATH A BUILDING
SUBSIDENCE INVERSION WILL LIKELY YIELD WIDESPREAD CU-STRATOCU
ACROSS THE AREA DURING PEAK HEATING. THE DEEP NEAR SFC UNSTABLE
LAYER MAY ALSO BE ENOUGH TO INDUCE SOME LOCALIZED FLURRY ACTIVITY
ESPECIALLY IN THE W WHERE CAA WILL BE MAXIMIZED. HAVE ADDED SOME
SLIGHT CHANCE POPS TO THE FORECAST ALONG WITH THE INCREASING
CLOUDS. OCEAN EFFECT CLOUDS ARE ALSO POSSIBLE ACROSS PORTIONS OF
CAPE COD GIVEN THE WIND TRAJECTORY AND OCEAN BL INSTABILITY.
ALSO...WITH THIS DEEP LAYER MIXING...MUCH OF THE MOMENTUM IN A
NEARLY 40 KT LLJ SHOULD BE TAPPED. THEREFORE...EXPECT BRISK NW
WINDS GUSTING 30-35 MPH AT TIMES THROUGH THE DAY. THIS WILL MAKE
FOR WIND CHILL VALUES IN THE 20S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
NOT TOO MUCH CHANGE FROM THE DAY AS CYCLONIC CURVATURE...DECENT
SFC PRES GRADIENT AND TRAPPED MID LVL MOISTURE REMAIN IN PLAY
ACROSS THE AREA. THEREFORE..EXPECT AT LEAST SOME CLOUDS AND WINDS
TO REMAIN THROUGH THE OVERNIGHT HOURS. WHILE THIS WILL LIMIT THE
ABILITY TO RADIATE...NORMAL DIURNAL TRENDS SHOULD STILL ALLOW MINS
INTO THE LOW TEENS AND 20S. WITH WINDS OF AROUND 10 MPH STILL
POSSIBLE...THIS WOULD YIELD SOME WIND CHILLS BELOW ZERO FOR
PORTIONS OF THE INTERIOR AND IN THE SINGLE DIGITS CLOSER TO THE
SHORELINES.
TUESDAY...
A COLD AND BRISK START IS EXPECTED AS WINDS CONTINUE TO GUST UP TO
ABOUT 20 MPH AFTER SUNRISE AND MIXING SETS UP. ANOTHER ROUND OF
PARTLY CLOUDY CONDITIONS AND HIGHER SUN ANGLES SHOULD ALLOW HIGHS
TO INCREASE INTO THE MID 20S TO LOW 30S DESPITE THIS COOLER START
BUT WITH WIND CHILL VALUES IN THE TEENS TO LOW 20S. MAINLY DRIER
WX AS NOSE OF HIGH PRES BEGINS TO BUILD OVER FROM THE
SW...LIMITING THE POTENTIAL FOR MORE FLURRY ACTIVITY IN COMPARISON
TO MON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* JANUARY-LIKE TEMPERATURES THIS WEEK AND AS WE ENTER MARCH NEXT
WEEKEND
* RISK FOR ACCUMULATING SNOW WED AND AGAIN NEXT WEEKEND
* OTHERWISE MAINLY DRY CONDITIONS PREVAIL
SYNOPTIC OVERVIEW...
NOT MUCH CHANGE IN THE FORECAST FROM PREVIOUS DAYS. HIGH AMPLITUDE
NORTHERN STREAM PATTERN DEVELOPS WITH POLAR VORTEX BEING DISPLACED
SOUTHWARD INTO ONTARIO BY THU. THIS RESULTS IN A STEADY STREAM OF
ARCTIC AIR INTO SOUTHERN NEW ENGLAND THIS WEEK AND INTO NEXT
WEEKEND. THAT/S THE EASY PART OF THE FORECAST. WHAT BECOMES
DIFFICULT TO NAIL DOWN AT THIS TIME RANGE IS THE INTENSITY AND TRACK
OF ANY EAST CYCLOGENESIS...AS ARCTIC SHORT WAVES PIVOT AROUND THE
SOUTHERN BASE OF THE POLAR VORTEX. FURTHER COMPLICATING THE FORECAST
IS IF PACIFIC ENERGY UNDERCUTTING THE WESTERN RIDGE INTERACTS
/PHASING VS UNPHASED/ WITH ARCTIC SHORT WAVE TROUGHS ALONG THE EAST
COAST.
MODEL PREFERENCES AND SENSIBLE WEATHER...
WEDNESDAY...00Z DETERMINISTIC GFS AND ECMWF IN AGREEMENT ON AN
UNPHASED SOLUTION WITH NORTHERN STREAM LOW MOVING ACROSS SOUTHEAST
CANADA AND EAST COAST CYCLOGENESIS TRACKING WELL SOUTHEAST OF
40N/70W BENCHMARK. HOWEVER APPEARS THERE WILL BE ENOUGH MID LEVEL
LIFT TO INDUCE AN INVERTED SURFACE TROUGH BETWEEN THESE TWO LOWS TO
GENERATE A FEW TENTHS OF QPF OVER SOUTHERN NEW ENGLAND. THUS A LOW
TO MODERATE RISK OF A FEW FLUFFY INCHES OF SNOW...WITH HIGHEST RISK
OVER SOUTHEAST MA.
HOWEVER CAN/T COMPLETELY RULE OUT A STRONGER/PHASED SOLUTION AS
ARCTIC SHORT WAVE/PV ANOMALY THAT INDUCES EAST COAST CYCLOGENESIS
IS CURRENTLY MOVING ACROSS NORTHWEST CANADA EARLY THIS MORNING.
MODELS LIKELY NOT SAMPLING THIS PACKET OF JET ENERGY VERY WELL
GIVEN THIS IS A DATA SPARSE AREA. THUS WILL HAVE TO WAIT UNTIL
THIS FEATURE ENTERS SOUTHERN CANADA BEFORE MODELS BEGIN BETTER
SAMPLING OF THIS JET ENERGY. IF THIS SHORT WAVE TROUGH IS MORE
AMPLIFIED THAN MODELS CURRENTLY SIMULATE...A TRACK CLOSER TO THE
COAST IS PLAUSIBLE. THEREFORE ITS STILL TOO EARLY TO LOCK INTO A
SINGLE SCENARIO. HOWEVER FOR THE MOMENT WILL PLAY THE MOST LIKELY
SCENARIO...A LOW TO MODERATE RISK OF A FEW INCHES OF FLUFFY SNOW.
THURSDAY THRU SUNDAY...ANOTHER ARCTIC FRONT MOVES ACROSS THE AREA
THU OR FRI WITH GEFS AND ECENS ENSEMBLE POST FRONTAL 850 MEAN TEMPS
VARYING FROM -15C TO -20C ACROSS SOUTHERN NEW ENGLAND. THUS COLDER
THAN NORMAL TEMPS HOWEVER ANY RECORD BREAKING COLD SHOULD REMAIN
WEST OF NEW ENGLAND ACROSS THE GREAT LAKES GIVEN PROXIMITY OF COLD
AIR CORE. WILL ALSO HAVE TO WATCH FOR POTENTIAL SNOW SQUALLS ALONG
AND AHEAD OF FRONTAL BOUNDARY...AS INCREASING SUN ANGLE /SAT MAR
1ST/ AND COLD AIR ALOFT WILL YIELD STEEP LOW LEVEL LAPSE RATES.
THEN NEXT WEEKEND THE FOCUS WILL BE ON PACIFIC ENERGY MARCHING
ACROSS THE SOUTHERN STATES AND ITS POSSIBLE INTERACTION/PHASING WITH
THE NORTHERN STREAM OVER THE NORTHEAST. THE 00Z GEFS AND ECENS
ENSEMBLE MEAN ARE WELL OFFSHORE WITH ANY CYCLOGENESIS...AS WELL AS
THE 00Z GFS. THE 00Z ECMWF IS MUCH CLOSER TO THE COAST BUT ALSO
WEAKER. GIVEN THE UNCERTAINTY WILL CONTINUE WITH CHANCE POPS FOR
NEXT WEEKEND.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
7 AM UPDATE...
NO MAJOR CHANGES FROM PREVIOUS 06Z TAFS.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
TODAY AND TUESDAY...HIGH CONFIDENCE. MAINLY VFR THROUGH THE
PERIOD...BUT SOME LOW CU BETWEEN 030-060 POSSIBLE THROUGH DAYLIGHT
HOURS ALONG WITH SOME LIGHT SNOW SHOWERS POSSIBLE MAINLY W OF A
IJD-ORH-EEN LINE TODAY. NW WINDS GUSTING 25-30 KT AT TIMES
TODAY...W WINDS GUST 20-25 KT ON TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
VFR ALONG WITH GUSTY WNW WINDS. THE EXCEPTION WILL BE WED WHEN WINDS
WILL BRIEFLY RELAX. HOWEVER A PERIOD OF SNOW IS POSSIBLE WED WITH
MVFR CONDITIONS. HIGHEST PROBABILITY OF SNOW AND MVFR CONDITIONS IS
ACROSS SOUTHEAST MA WED.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TUESDAY...HIGH CONFIDENCE.
W-NW WINDS WILL BE INCREASING THROUGH THE DAY TODAY WITH GUSTS
WIDESPREAD 25-30 KT EXPECTED. A FEW GUSTS MAY APPROACH GALE
FORCE...BUT THE MAJORITY SHOULD REMAIN BELOW. THESE WINDS WILL
MAINTAIN THROUGH THE OVERNIGHT HOURS TONIGHT...ONLY DIMINISHING
INTO THE MORNING HOURS FOR TUE THEN DROPPING BELOW SMALL CRAFT
THRESHOLDS BY THE LATE DAY TUE.
WITH INCREASING WINDS EXPECT SEAS TO BUILD AS WELL...REACHING
5-7FT AT TIMES MAINLY ON THE OCEAN WATERS.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
GUSTY WNW WINDS AND PERIODS OF FREEZING SPRAY ARE EXPECTED AS ARCTIC
AIR OVERSPREADS THE REGION. WINDS BRIEFLY RELAX WED AS ONE AREA OF
LOW PRES TRACKS ACROSS SOUTHEAST CANADA AND A POTENTIAL GALE CENTER
PASSES SOUTHEAST OF 40N/70W BENCHMARK. A PERIOD OF SNOW WITH REDUCED
VSBY IS LIKELY WED ESPECIALLY OVER THE WATERS SOUTHEAST OF
NANTUCKET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST TUESDAY FOR ANZ230>237-251.
SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...NOCERA/DOODY
NEAR TERM...KJC/DOODY
SHORT TERM...DOODY
LONG TERM...NOCERA
AVIATION...NOCERA/DOODY
MARINE...NOCERA/DOODY
AREA FORECAST DISCUSSION
NWS TAUNTON MA
713 AM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT WAS EXITING THE REGION EARLY THIS MORNING...
BRINGING PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND.
MAINLY DRY CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE
MOVES ACROSS. ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING
SNOWFALL FOR WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW
ENGLAND. ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
7 AM UPDATE...
COLD FRONT NOW OVER NANTUCKET WILL MOVE OFFSHORE SHORTLY. STRONG
COLD AIR ADVECTION BEHIND THE FRONT WITH SURFACE DEW PTS ALREADY
FALLING INTO THE SINGLE DIGITS ACROSS NORTHEAST MA. CLOUD SHIELD
OVER SOUTHEAST MA ASSOCIATED WITH THE FRONT WILL MOVE OFFSHORE
LATER THIS MORNING. HOWEVER POST FRONTAL CLOUDS WILL FILL BACK IN
AS COLD AIR ALOFT COMBINES WITH DIURNAL HEATING TO YIELD STEEP LOW
LEVEL LAPSE RATES. THIS COUPLED WITH CYCLONIC FLOW ALOFT MAY YIELD
SCT SNOW SHOWERS THIS AFTERNOON...ESPECIALLY OVER THE HIGHER
TERRAIN WHERE UPSLOPE FLOW WILL PROVIDE ADDITIONAL LIFT. HOWEVER DRY
LOW LEVELS MAY ONLY YIELD SOME FLURRIES OR VIRGA. PREVIOUS
FORECAST CAPTURES THESE DETAILS NICELY...THUS NO MAJOR CHANGES
WITH THIS FORECAST UPDATE. EARLIER DISCUSSION BELOW.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A COMBINATION OF BOTH OBS AND MSAS SUGGEST SFC COLD FRONT HAS
MOVED OFFSHORE OF ALL SRN NEW ENGLAND COASTLINES SAVE FOR THE
CAPE/ISLANDS AS OF 0830Z. NOW IN CLOSE ASSOCIATION WITH THIS FRONT
IS A BAND OF WSR-88D ECHOS OF 25-30 DBZ WHICH ALSO CONTINUE TO
GRADUALLY SLIDE OFF THE S COAST AND SHOULD BE OFFSHORE OF
EVERYWHERE BY 10-12Z BASED ON CURRENT SPEED AND TIMING. DESPITE
THE ECHOS...PRECIP HAS REALLY STRUGGLED TO REACH THE SFC THANKS TO
10-15F DWPT DEPRESSIONS ACROSS THE REGION. EVEN THEN...WITH SFC
TEMPS ABOVE FREEZING AND A LACK OF HEAVY PRECIP TO FORCE THE NEAR
SFC LAYER TO WET-BULB...ANY PRECIP THAT HAS REACHED THE SFC HAS
BEEN IN THE FORM OF LIGHT RAIN. BASED EARLY MORNING POPS ON THE
LATEST RAP WHICH CONTINUES TO FOLLOW THIS BAND WELL BUT CAPPED ANY
POPS AT CHANCE.
OTHERWISE TODAY...AFTER THE FRONT/PRECIP BAND SHIFTS
OFFSHORE...STRONG COLD ADVECTION WILL DEFINE THE WX. H85
TEMPERATURES WILL BE DECLINING FROM AN AVERAGE OF ABOUT -5C TO
ABOUT -16C BY THE OVERNIGHT HOURS TONIGHT. DRY AIR WILL ALSO BE
RAPIDLY MOVING IN WITH TIME AS WELL. THEREFORE...EXPECT HIGH TEMPS
TO OCCUR BY LATE THIS MORNING WITH COOLING EXPECTED THROUGH THE
AFTERNOON HOURS...WITH RANGES FROM THE LOW TO UPPER 30S. THE
COMBINATION OF STRONG CYCLONIC CURVATURE ALOFT WITH A SHORTWAVE
MOVING ACROSS THE AREA...STEEP SFC-H9 LAPSE RATES ON THE ORDER OF
8C/KM AND A BIT OF TRAPPED MID LVL MOISTURE BENEATH A BUILDING
SUBSIDENCE INVERSION WILL LIKELY YIELD WIDESPREAD CU-STRATOCU
ACROSS THE AREA DURING PEAK HEATING. THE DEEP NEAR SFC UNSTABLE
LAYER MAY ALSO BE ENOUGH TO INDUCE SOME LOCALIZED FLURRY ACTIVITY
ESPECIALLY IN THE W WHERE CAA WILL BE MAXIMIZED. HAVE ADDED SOME
SLIGHT CHANCE POPS TO THE FORECAST ALONG WITH THE INCREASING
CLOUDS. OCEAN EFFECT CLOUDS ARE ALSO POSSIBLE ACROSS PORTIONS OF
CAPE COD GIVEN THE WIND TRAJECTORY AND OCEAN BL INSTABILITY.
ALSO...WITH THIS DEEP LAYER MIXING...MUCH OF THE MOMENTUM IN A
NEARLY 40 KT LLJ SHOULD BE TAPPED. THEREFORE...EXPECT BRISK NW
WINDS GUSTING 30-35 MPH AT TIMES THROUGH THE DAY. THIS WILL MAKE
FOR WIND CHILL VALUES IN THE 20S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
NOT TOO MUCH CHANGE FROM THE DAY AS CYCLONIC CURVATURE...DECENT
SFC PRES GRADIENT AND TRAPPED MID LVL MOISTURE REMAIN IN PLAY
ACROSS THE AREA. THEREFORE..EXPECT AT LEAST SOME CLOUDS AND WINDS
TO REMAIN THROUGH THE OVERNIGHT HOURS. WHILE THIS WILL LIMIT THE
ABILITY TO RADIATE...NORMAL DIURNAL TRENDS SHOULD STILL ALLOW MINS
INTO THE LOW TEENS AND 20S. WITH WINDS OF AROUND 10 MPH STILL
POSSIBLE...THIS WOULD YIELD SOME WIND CHILLS BELOW ZERO FOR
PORTIONS OF THE INTERIOR AND IN THE SINGLE DIGITS CLOSER TO THE
SHORELINES.
TUESDAY...
A COLD AND BRISK START IS EXPECTED AS WINDS CONTINUE TO GUST UP TO
ABOUT 20 MPH AFTER SUNRISE AND MIXING SETS UP. ANOTHER ROUND OF
PARTLY CLOUDY CONDITIONS AND HIGHER SUN ANGLES SHOULD ALLOW HIGHS
TO INCREASE INTO THE MID 20S TO LOW 30S DESPITE THIS COOLER START
BUT WITH WIND CHILL VALUES IN THE TEENS TO LOW 20S. MAINLY DRIER
WX AS NOSE OF HIGH PRES BEGINS TO BUILD OVER FROM THE
SW...LIMITING THE POTENTIAL FOR MORE FLURRY ACTIVITY IN COMPARISON
TO MON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* JANUARY-LIKE TEMPERATURES THIS WEEK AND AS WE ENTER MARCH NEXT
WEEKEND
* RISK FOR ACCUMULATING SNOW WED AND AGAIN NEXT WEEKEND
* OTHERWISE MAINLY DRY CONDITIONS PREVAIL
SYNOPTIC OVERVIEW...
NOT MUCH CHANGE IN THE FORECAST FROM PREVIOUS DAYS. HIGH AMPLITUDE
NORTHERN STREAM PATTERN DEVELOPS WITH POLAR VORTEX BEING DISPLACED
SOUTHWARD INTO ONTARIO BY THU. THIS RESULTS IN A STEADY STREAM OF
ARCTIC AIR INTO SOUTHERN NEW ENGLAND THIS WEEK AND INTO NEXT
WEEKEND. THAT/S THE EASY PART OF THE FORECAST. WHAT BECOMES
DIFFICULT TO NAIL DOWN AT THIS TIME RANGE IS THE INTENSITY AND TRACK
OF ANY EAST CYCLOGENESIS...AS ARCTIC SHORT WAVES PIVOT AROUND THE
SOUTHERN BASE OF THE POLAR VORTEX. FURTHER COMPLICATING THE FORECAST
IS IF PACIFIC ENERGY UNDERCUTTING THE WESTERN RIDGE INTERACTS
/PHASING VS UNPHASED/ WITH ARCTIC SHORT WAVE TROUGHS ALONG THE EAST
COAST.
MODEL PREFERENCES AND SENSIBLE WEATHER...
WEDNESDAY...00Z DETERMINISTIC GFS AND ECMWF IN AGREEMENT ON AN
UNPHASED SOLUTION WITH NORTHERN STREAM LOW MOVING ACROSS SOUTHEAST
CANADA AND EAST COAST CYCLOGENESIS TRACKING WELL SOUTHEAST OF
40N/70W BENCHMARK. HOWEVER APPEARS THERE WILL BE ENOUGH MID LEVEL
LIFT TO INDUCE AN INVERTED SURFACE TROUGH BETWEEN THESE TWO LOWS TO
GENERATE A FEW TENTHS OF QPF OVER SOUTHERN NEW ENGLAND. THUS A LOW
TO MODERATE RISK OF A FEW FLUFFY INCHES OF SNOW...WITH HIGHEST RISK
OVER SOUTHEAST MA.
HOWEVER CAN/T COMPLETELY RULE OUT A STRONGER/PHASED SOLUTION AS
ARCTIC SHORT WAVE/PV ANOMALY THAT INDUCES EAST COAST CYCLOGENESIS
IS CURRENTLY MOVING ACROSS NORTHWEST CANADA EARLY THIS MORNING.
MODELS LIKELY NOT SAMPLING THIS PACKET OF JET ENERGY VERY WELL
GIVEN THIS IS A DATA SPARSE AREA. THUS WILL HAVE TO WAIT UNTIL
THIS FEATURE ENTERS SOUTHERN CANADA BEFORE MODELS BEGIN BETTER
SAMPLING OF THIS JET ENERGY. IF THIS SHORT WAVE TROUGH IS MORE
AMPLIFIED THAN MODELS CURRENTLY SIMULATE...A TRACK CLOSER TO THE
COAST IS PLAUSIBLE. THEREFORE ITS STILL TOO EARLY TO LOCK INTO A
SINGLE SCENARIO. HOWEVER FOR THE MOMENT WILL PLAY THE MOST LIKELY
SCENARIO...A LOW TO MODERATE RISK OF A FEW INCHES OF FLUFFY SNOW.
THURSDAY THRU SUNDAY...ANOTHER ARCTIC FRONT MOVES ACROSS THE AREA
THU OR FRI WITH GEFS AND ECENS ENSEMBLE POST FRONTAL 850 MEAN TEMPS
VARYING FROM -15C TO -20C ACROSS SOUTHERN NEW ENGLAND. THUS COLDER
THAN NORMAL TEMPS HOWEVER ANY RECORD BREAKING COLD SHOULD REMAIN
WEST OF NEW ENGLAND ACROSS THE GREAT LAKES GIVEN PROXIMITY OF COLD
AIR CORE. WILL ALSO HAVE TO WATCH FOR POTENTIAL SNOW SQUALLS ALONG
AND AHEAD OF FRONTAL BOUNDARY...AS INCREASING SUN ANGLE /SAT MAR
1ST/ AND COLD AIR ALOFT WILL YIELD STEEP LOW LEVEL LAPSE RATES.
THEN NEXT WEEKEND THE FOCUS WILL BE ON PACIFIC ENERGY MARCHING
ACROSS THE SOUTHERN STATES AND ITS POSSIBLE INTERACTION/PHASING WITH
THE NORTHERN STREAM OVER THE NORTHEAST. THE 00Z GEFS AND ECENS
ENSEMBLE MEAN ARE WELL OFFSHORE WITH ANY CYCLOGENESIS...AS WELL AS
THE 00Z GFS. THE 00Z ECMWF IS MUCH CLOSER TO THE COAST BUT ALSO
WEAKER. GIVEN THE UNCERTAINTY WILL CONTINUE WITH CHANCE POPS FOR
NEXT WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
7 AM UPDATE...
NO MAJOR CHANGES FROM PREVIOUS 06Z TAFS.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
TODAY AND TUESDAY...HIGH CONFIDENCE. MAINLY VFR THROUGH THE
PERIOD...BUT SOME LOW CU BETWEEN 030-060 POSSIBLE THROUGH DAYLIGHT
HOURS ALONG WITH SOME LIGHT SNOW SHOWERS POSSIBLE MAINLY W OF A
IJD-ORH-EEN LINE TODAY. NW WINDS GUSTING 25-30 KT AT TIMES
TODAY...W WINDS GUST 20-25 KT ON TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
VFR ALONG WITH GUSTY WNW WINDS. THE EXCEPTION WILL BE WED WHEN WINDS
WILL BRIEFLY RELAX. HOWEVER A PERIOD OF SNOW IS POSSIBLE WED WITH
MVFR CONDITIONS. HIGHEST PROBABILITY OF SNOW AND MVFR CONDITIONS IS
ACROSS SOUTHEAST MA WED.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TUESDAY...HIGH CONFIDENCE.
W-NW WINDS WILL BE INCREASING THROUGH THE DAY TODAY WITH GUSTS
WIDESPREAD 25-30 KT EXPECTED. A FEW GUSTS MAY APPROACH GALE
FORCE...BUT THE MAJORITY SHOULD REMAIN BELOW. THESE WINDS WILL
MAINTAIN THROUGH THE OVERNIGHT HOURS TONIGHT...ONLY DIMINISHING
INTO THE MORNING HOURS FOR TUE THEN DROPPING BELOW SMALL CRAFT
THRESHOLDS BY THE LATE DAY TUE.
WITH INCREASING WINDS EXPECT SEAS TO BUILD AS WELL...REACHING
5-7FT AT TIMES MAINLY ON THE OCEAN WATERS.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
GUSTY WNW WINDS AND PERIODS OF FREEZING SPRAY ARE EXPECTED AS ARCTIC
AIR OVERSPREADS THE REGION. WINDS BRIEFLY RELAX WED AS ONE AREA OF
LOW PRES TRACKS ACROSS SOUTHEAST CANADA AND A POTENTIAL GALE CENTER
PASSES SOUTHEAST OF 40N/70W BENCHMARK. A PERIOD OF SNOW WITH REDUCED
VSBY IS LIKELY WED ESPECIALLY OVER THE WATERS SOUTHEAST OF
NANTUCKET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EST TUESDAY FOR ANZ230>237-251.
SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...NOCERA/DOODY
NEAR TERM...NOCERA/DOODY
SHORT TERM...DOODY
LONG TERM...NOCERA
AVIATION...NOCERA/DOODY
MARINE...NOCERA/DOODY
AREA FORECAST DISCUSSION
NWS TAUNTON MA
357 AM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT CROSSES THE REGION TONIGHT...BRINGING
PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND. MAINLY DRY
CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE MOVES ACROSS.
ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING SNOWFALL FOR
WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW ENGLAND.
ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A COMBINATION OF BOTH OBS AND MSAS SUGGEST SFC COLD FRONT HAS
MOVED OFFSHORE OF ALL SRN NEW ENGLAND COASTLINES SAVE FOR THE
CAPE/ISLANDS AS OF 0830Z. NOW IN CLOSE ASSOCIATION WITH THIS FRONT
IS A BAND OF WSR-88D ECHOS OF 25-30 DBZ WHICH ALSO CONTINUE TO
GRADUALLY SLIDE OFF THE S COAST AND SHOULD BE OFFSHORE OF
EVERYWHERE BY 10-12Z BASED ON CURRENT SPEED AND TIMING. DESPITE
THE ECHOS...PRECIP HAS REALLY STRUGGLED TO REACH THE SFC THANKS TO
10-15F DWPT DEPRESSIONS ACROSS THE REGION. EVEN THEN...WITH SFC
TEMPS ABOVE FREEZING AND A LACK OF HEAVY PRECIP TO FORCE THE NEAR
SFC LAYER TO WET-BULB...ANY PRECIP THAT HAS REACHED THE SFC HAS
BEEN IN THE FORM OF LIGHT RAIN. BASED EARLY MORNING POPS ON THE
LATEST RAP WHICH CONTINUES TO FOLLOW THIS BAND WELL BUT CAPPED ANY
POPS AT CHANCE.
OTHERWISE TODAY...AFTER THE FRONT/PRECIP BAND SHIFTS
OFFSHORE...STRONG COLD ADVECTION WILL DEFINE THE WX. H85
TEMPERATURES WILL BE DECLINING FROM AN AVERAGE OF ABOUT -5C TO
ABOUT -16C BY THE OVERNIGHT HOURS TONIGHT. DRY AIR WILL ALSO BE
RAPIDLY MOVING IN WITH TIME AS WELL. THEREFORE...EXPECT HIGH TEMPS
TO OCCUR BY LATE THIS MORNING WITH COOLING EXPECTED THROUGH THE
AFTERNOON HOURS...WITH RANGES FROM THE LOW TO UPPER 30S. THE
COMBINATION OF STRONG CYCLONIC CURVATURE ALOFT WITH A SHORTWAVE
MOVING ACROSS THE AREA...STEEP SFC-H9 LAPSE RATES ON THE ORDER OF
8C/KM AND A BIT OF TRAPPED MID LVL MOISTURE BENEATH A BUILDING
SUBSIDENCE INVERSION WILL LIKELY YIELD WIDESPREAD CU-STRATOCU
ACROSS THE AREA DURING PEAK HEATING. THE DEEP NEAR SFC UNSTABLE
LAYER MAY ALSO BE ENOUGH TO INDUCE SOME LOCALIZED FLURRY ACTIVITY
ESPECIALLY IN THE W WHERE CAA WILL BE MAXIMIZED. HAVE ADDED SOME
SLIGHT CHANCE POPS TO THE FORECAST ALONG WITH THE INCREASING
CLOUDS. OCEAN EFFECT CLOUDS ARE ALSO POSSIBLE ACROSS PORTIONS OF
CAPE COD GIVEN THE WIND TRAJECTORY AND OCEAN BL INSTABILITY.
ALSO...WITH THIS DEEP LAYER MIXING...MUCH OF THE MOMENTUM IN A
NEARLY 40 KT LLJ SHOULD BE TAPPED. THEREFORE...EXPECT BRISK NW
WINDS GUSTING 30-35 MPH AT TIMES THROUGH THE DAY. THIS WILL MAKE
FOR WIND CHILL VALUES IN THE 20S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
TONIGHT...
NOT TOO MUCH CHANGE FROM THE DAY AS CYCLONIC CURVATURE...DECENT
SFC PRES GRADIENT AND TRAPPED MID LVL MOISTURE REMAIN IN PLAY
ACROSS THE AREA. THEREFORE..EXPECT AT LEAST SOME CLOUDS AND WINDS
TO REMAIN THROUGH THE OVERNIGHT HOURS. WHILE THIS WILL LIMIT THE
ABILITY TO RADIATE...NORMAL DIURNAL TRENDS SHOULD STILL ALLOW MINS
INTO THE LOW TEENS AND 20S. WITH WINDS OF AROUND 10 MPH STILL
POSSIBLE...THIS WOULD YIELD SOME WIND CHILLS BELOW ZERO FOR
PORTIONS OF THE INTERIOR AND IN THE SINGLE DIGITS CLOSER TO THE
SHORELINES.
TUESDAY...
A COLD AND BRISK START IS EXPECTED AS WINDS CONTINUE TO GUST UP TO
ABOUT 20 MPH AFTER SUNRISE AND MIXING SETS UP. ANOTHER ROUND OF
PARTLY CLOUDY CONDITIONS AND HIGHER SUN ANGLES SHOULD ALLOW HIGHS
TO INCREASE INTO THE MID 20S TO LOW 30S DESPITE THIS COOLER START
BUT WITH WIND CHILL VALUES IN THE TEENS TO LOW 20S. MAINLY DRIER
WX AS NOSE OF HIGH PRES BEGINS TO BUILD OVER FROM THE
SW...LIMITING THE POTENTIAL FOR MORE FLURRY ACTIVITY IN COMPARISON
TO MON.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* JANUARY-LIKE TEMPERATURES THIS WEEK AND AS WE ENTER MARCH NEXT
WEEKEND
* RISK FOR ACCUMULATING SNOW WED AND AGAIN NEXT WEEKEND
* OTHERWISE MAINLY DRY CONDITIONS PREVAIL
SYNOPTIC OVERVIEW...
NOT MUCH CHANGE IN THE FORECAST FROM PREVIOUS DAYS. HIGH AMPLITUDE
NORTHERN STREAM PATTERN DEVELOPS WITH POLAR VORTEX BEING DISPLACED
SOUTHWARD INTO ONTARIO BY THU. THIS RESULTS IN A STEADY STREAM OF
ARCTIC AIR INTO SOUTHERN NEW ENGLAND THIS WEEK AND INTO NEXT
WEEKEND. THAT/S THE EASY PART OF THE FORECAST. WHAT BECOMES
DIFFICULT TO NAIL DOWN AT THIS TIME RANGE IS THE INTENSITY AND TRACK
OF ANY EAST CYCLOGENESIS...AS ARCTIC SHORT WAVES PIVOT AROUND THE
SOUTHERN BASE OF THE POLAR VORTEX. FURTHER COMPLICATING THE FORECAST
IS IF PACIFIC ENERGY UNDERCUTTING THE WESTERN RIDGE INTERACTS
/PHASING VS UNPHASED/ WITH ARCTIC SHORT WAVE TROUGHS ALONG THE EAST
COAST.
MODEL PREFERENCES AND SENSIBLE WEATHER...
WEDNESDAY...00Z DETERMINISTIC GFS AND ECMWF IN AGREEMENT ON AN
UNPHASED SOLUTION WITH NORTHERN STREAM LOW MOVING ACROSS SOUTHEAST
CANADA AND EAST COAST CYCLOGENESIS TRACKING WELL SOUTHEAST OF
40N/70W BENCHMARK. HOWEVER APPEARS THERE WILL BE ENOUGH MID LEVEL
LIFT TO INDUCE AN INVERTED SURFACE TROUGH BETWEEN THESE TWO LOWS TO
GENERATE A FEW TENTHS OF QPF OVER SOUTHERN NEW ENGLAND. THUS A LOW
TO MODERATE RISK OF A FEW FLUFFY INCHES OF SNOW...WITH HIGHEST RISK
OVER SOUTHEAST MA.
HOWEVER CAN/T COMPLETELY RULE OUT A STRONGER/PHASED SOLUTION AS
ARCTIC SHORT WAVE/PV ANOMALY THAT INDUCES EAST COAST CYCLOGENESIS
IS CURRENTLY MOVING ACROSS NORTHWEST CANADA EARLY THIS MORNING.
MODELS LIKELY NOT SAMPLING THIS PACKET OF JET ENERGY VERY WELL
GIVEN THIS IS A DATA SPARSE AREA. THUS WILL HAVE TO WAIT UNTIL
THIS FEATURE ENTERS SOUTHERN CANADA BEFORE MODELS BEGIN BETTER
SAMPLING OF THIS JET ENERGY. IF THIS SHORT WAVE TROUGH IS MORE
AMPLIFIED THAN MODELS CURRENTLY SIMULATE...A TRACK CLOSER TO THE
COAST IS PLAUSIBLE. THEREFORE ITS STILL TOO EARLY TO LOCK INTO A
SINGLE SCENARIO. HOWEVER FOR THE MOMENT WILL PLAY THE MOST LIKELY
SCENARIO...A LOW TO MODERATE RISK OF A FEW INCHES OF FLUFFY SNOW.
THURSDAY THRU SUNDAY...ANOTHER ARCTIC FRONT MOVES ACROSS THE AREA
THU OR FRI WITH GEFS AND ECENS ENSEMBLE POST FRONTAL 850 MEAN TEMPS
VARYING FROM -15C TO -20C ACROSS SOUTHERN NEW ENGLAND. THUS COLDER
THAN NORMAL TEMPS HOWEVER ANY RECORD BREAKING COLD SHOULD REMAIN
WEST OF NEW ENGLAND ACROSS THE GREAT LAKES GIVEN PROXIMITY OF COLD
AIR CORE. WILL ALSO HAVE TO WATCH FOR POTENTIAL SNOW SQUALLS ALONG
AND AHEAD OF FRONTAL BOUNDARY...AS INCREASING SUN ANGLE /SAT MAR
1ST/ AND COLD AIR ALOFT WILL YIELD STEEP LOW LEVEL LAPSE RATES.
THEN NEXT WEEKEND THE FOCUS WILL BE ON PACIFIC ENERGY MARCHING
ACROSS THE SOUTHERN STATES AND ITS POSSIBLE INTERACTION/PHASING WITH
THE NORTHERN STREAM OVER THE NORTHEAST. THE 00Z GEFS AND ECENS
ENSEMBLE MEAN ARE WELL OFFSHORE WITH ANY CYCLOGENESIS...AS WELL AS
THE 00Z GFS. THE 00Z ECMWF IS MUCH CLOSER TO THE COAST BUT ALSO
WEAKER. GIVEN THE UNCERTAINTY WILL CONTINUE WITH CHANCE POPS FOR
NEXT WEEKEND.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
THROUGH 12Z...MODERATE CONFIDENCE.
A FEW LIGHT SNOW/RAIN SHOWERS WILL SKIRT CT/RI/SE MA TERMINALS.
LITTLE IF ANY ACCUMULATION IS EXPECTED...BUT THE BEST CHANCE WILL
BE ACROSS SE MA. MAINLY VFR...BUT A SHORT PERIOD OF MVFR
CONDITIONS ARE POSSIBLE IN ANY SHOWERS.
TODAY AND TUESDAY...HIGH CONFIDENCE.
MAINLY VFR THROUGH THE PERIOD...BUT SOME LOW CU BETWEEN 030-060
POSSIBLE THROUGH DAYLIGHT HOURS ALONG WITH SOME LIGHT SNOW
SHOWERS POSSIBLE MAINLY W OF A IJD-ORH-EEN LINE TODAY. NW WINDS
GUSTING 25-30 KT AT TIMES TODAY...W WINDS GUST 20-25 KT ON TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
VFR ALONG WITH GUSTY WNW WINDS. THE EXCEPTION WILL BE WED WHEN WINDS
WILL BRIEFLY RELAX. HOWEVER A PERIOD OF SNOW IS POSSIBLE WED WITH
MVFR CONDITIONS. HIGHEST PROBABILITY OF SNOW AND MVFR CONDITIONS IS
ACROSS SOUTHEAST MA WED.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TUESDAY...HIGH CONFIDENCE.
W-NW WINDS WILL BE INCREASING THROUGH THE DAY TODAY WITH GUSTS
WIDESPREAD 25-30 KT EXPECTED. A FEW GUSTS MAY APPROACH GALE
FORCE...BUT THE MAJORITY SHOULD REMAIN BELOW. THESE WINDS WILL
MAINTAIN THROUGH THE OVERNIGHT HOURS TONIGHT...ONLY DIMINISHING
INTO THE MORNING HOURS FOR TUE THEN DROPPING BELOW SMALL CRAFT
THRESHOLDS BY THE LATE DAY TUE.
WITH INCREASING WINDS EXPECT SEAS TO BUILD AS WELL...REACHING
5-7FT AT TIMES MAINLY ON THE OCEAN WATERS.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
GUSTY WNW WINDS AND PERIODS OF FREEZING SPRAY ARE EXPECTED AS ARCTIC
AIR OVERSPREADS THE REGION. WINDS BRIEFLY RELAX WED AS ONE AREA OF
LOW PRES TRACKS ACROSS SOUTHEAST CANADA AND A POTENTIAL GALE CENTER
PASSES SOUTHEAST OF 40N/70W BENCHMARK. A PERIOD OF SNOW WITH REDUCED
VSBY IS LIKELY WED ESPECIALLY OVER THE WATERS SOUTHEAST OF
NANTUCKET.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 1 PM EST
TUESDAY FOR ANZ230>237-251.
SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST
TUESDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...NOCERA/DOODY
NEAR TERM...DOODY
SHORT TERM...DOODY
LONG TERM...NOCERA
AVIATION...NOCERA/DOODY
MARINE...NOCERA/DOODY
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1241 AM EST MON FEB 24 2014
.SYNOPSIS...
A STRONG COLD FRONT CROSSES THE REGION TONIGHT...BRINGING
PROGRESSIVELY COLDER CONDITIONS THROUGH NEXT WEEKEND. MAINLY DRY
CONDITIONS WILL BE IN PLACE AS LARGE HIGH PRESSURE MOVES ACROSS.
ONE EXCEPTION WILL BE FOR THE RISK OF ACCUMULATING SNOWFALL FOR
WEDNESDAY AS LOW PRESSURE DEVELOPS WELL SOUTH OF NEW ENGLAND.
ANOTHER LOW MAY BRING SOME SNOWFALL NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
1 AM UPDATE...
BAND OF PRECIP CONTINUES TO WORK INTO CT AROUND MIDNIGHT WITH SOME
25-30 DBZ RETURNS APPARENT. HOWEVER...WITH DWPT DEPRESSIONS
REMAINING IN THE 10-15F RANGE...THESE ECHOS ARE LIKELY NOT
REACHING THE GROUND FOR THE MOST PART. OBS SITES ACROSS SRN NY DO
SHOW SOME LIGHT RAINFALL...BUT IT WILL LIKELY TAKE A BIT LONGER TO
CREEP INTO SRN NY. CURRENT HRRR SEEMS TO BE HANDLING THE PRECIP
CHANCES BEST SO POPS WERE TRENDED TOWARD ITS THINKING...SUGGESTING
A LIGHT BAND OF SN/RA MOVES ACROSS CT/RI/SE MA THROUGH ABOUT 12Z.
SHOULD PRECIP REMAIN LIGHT...MANY LOCATIONS MAY START AS RAIN OR
NEVER CHANGE OVER AT ALL...BUT CONTINUE SUGGEST SOME SNOWFALL IF
THE HIGHER DBZ ECHOS ARE ACTUALLY REACHING THE GROUND.
MEANWHILE THE COLD FRONT IS IN CENTRAL CT VALLEY AND THROUGH SRN
NH. SO IT IS CATCHING UP WITH THE PRECIP BAND. INCREASING THE
LIKELIHOOD FOR ENHANCED PRECIP AS THE NEAR SFC LIFT WILL BE
STRENGTHENED. IT WILL LIKELY FOLLOW THE FRONT OFFSHORE THROUGH 12Z
PER LATEST HRRR.
PREVIOUS DISCUSSION...
A STRONG COLD FRONT CROSSES THE REGION TONIGHT...BRINGING A
RETURN TO COLDER WEATHER. AT THE SAME TIME...A SHORTWAVE WILL
APPROACH FROM THE SOUTHWEST. THIS MAY BRING A BRIEF PERIOD OF
LIGHT PRECIP LATE TONIGHT...TO THE SOUTH OF THE MA TURNPIKE. THIS
DISTURBANCE ONLY CONTAINS A NARROW AXIS OF DEEP MOISTURE AND IS
FAIRLY PROGRESSIVE. THEREFORE...EXPECT PRECIP AMOUNTS TO BE QUITE
LIGHT. IN FACT...BOUNDARY LAYER IS INITIALLY WARM ENOUGH TO
SUPPORT LIGHT RAIN AT THE ONSET IN SOME AREAS BEFORE A CHANGE TO
LIGHT SNOW.
WITH ALL THAT SAID...A DUSTING TO MAINLY LESS THAN 1 INCH OF SNOW
IS POSSIBLE TO THE SOUTH OF THE MA TURNPIKE LATE TONIGHT. ANY
LIGHT SNOW WILL BE PRETTY MUCH DONE BY DAYBREAK...BUT A FEW SLICK
SPOTS WILL BE POSSIBLE FOR THE AM RUSH. LOW TEMPS BY DAYBREAK
MONDAY WILL MAINLY BE IN THE 20S...TO PERHAPS SOME LOWER 30S
ALONG THE FAR SOUTHEAST NEW ENGLAND COAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
***MUCH COLDER AND WINDY WEATHER RETURNS ON MONDAY***
MONDAY...
A MUCH COLDER AND WINDY DAY FOLLOWS TONIGHT/S COLD FRONTAL PASSAGE.
HIGH TEMPS WILL ONLY RECOVER INTO THE UPPER 20S TO MIDDLE 30S...AS
NORTHWEST WINDS GUST TO BETWEEN 25 AND 35 MPH LATE IN THE
MORNING/AFTERNOON. WHILE A FAIR AMOUNT OF SUNSHINE IS EXPECTED
ALONG THE COASTAL PLAIN EARLY...A DECK OF SCATTERED TO BROKEN
DIURNAL CUMULUS CLOUDS WILL WORK ACROSS THE REGION FROM THE WEST AS
THE DAY WEARS ON. A BRIEF PASSING FLURRY/SNOW SHOWER OR TWO WILL
ALSO BE POSSIBLE...BUT THE INFILTRATION OF DRIER AIR WILL PROBABLY
PREVENT LOCALIZED HEAVIER SNOW SHOWERS/SQUALLS.
MONDAY NIGHT...
DRY...BUT COLD AND BLUSTERY WEATHER CONTINUES ACROSS SOUTHERN NEW
ENGLAND. NORTHWEST FLOW AND COLD ADVECTION WILL RESULT IN MOST
LOCATIONS BOTTOMING OUT IN THE TEENS BY DAYBREAK TUESDAY. WIND
CHILLS WILL DIP INTO THE SINGLE DIGITS ACROSS MOST OF THE REGION.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
HIGHLIGHTS...
* TEMPERATURES WILL STEADILY FALL AS ARCTIC AIR WORKS INTO THE
REGION THROUGH NEXT WEEKEND
* LOW PRESSURE PASSING SOUTH OF NEW ENGLAND WILL INCREASE CHANCES
FOR ACCUMULATING SNOWS WEDNESDAY
* ANOTHER LOW IS POSSIBLE DURING NEXT WEEKEND WHICH COULD BRING SOME
ACCUMULATING SNOW
OVERVIEW AND MODEL PREFERENCES...
MEDIUM RANGE MODELS AND ENSEMBLES CONTINUE TO SIGNAL DEVELOPMENT
OF LONGITUDINAL RIDGING ACROSS THE EASTERN PACIFIC TO ALASKA...
WHICH IN RETURN WILL BRING ANOTHER ROUND OF ARCTIC AIR FROM THE
NORTH POLE AND NORTHERN CANADA TOWARD THE CENTRAL AND EASTERN U.S.
WITH CUTOFF H5 LOW TAKING UP RESIDENCE NEAR HUDSON AND JAMES BAYS.
PRIOR TO THIS SETTING UP...NOTING A GOOD SHORT WAVE IN THIS FLOW
MOVING OUT OF SASKATCHEWAN AND MANITOBA EARLY TUE. THIS WILL CARVE
OUT A GOOD LONG WAVE TROUGH PROGRESSING E LATER TUE AND WED. AT
THE SURFACE...WILL SEE DEVELOPING LOW PRES CROSSING THE GREAT
LAKES WHILE ANOTHER SYSTEM WILL MOVE OUT OF THE NORTHERN GULF OF
MEXICO BY LATE TUE. THE SYSTEM REMAINS PROGRESSIVE...THOUGH WITH
THE COLD AIR IN PLACE...THERE IS A GOOD RISK FOR ACCUMULATING
SNOWS. SOME MODEL SPREAD NOTED ESPECIALLY WITH QPF VALUES AND HOW
FAR NORTH THESE PROGRESS. ALSO UNCERTAIN WHETHER THESE SYSTEMS
PHASE...THOUGH LAST SEVERAL RUNS HAVE SUGGESTED THEY REMAIN
SEPARATE WITH THE SOUTHERN LOW PASSING WELL SE OF THE 40N/70W
BENCHMARK.
BEYOND MID WEEK...HEART OF ARCTIC AIR SLOWLY WORKS S OUT OF
CENTRAL AND EASTERN CANADA...THOUGH COLDEST AIR DOES NOT LOOK TO
ARRIVE UNTIL LATE NEXT WEEK. H85 TEMPS PROGRESSIVELY DROP THROUGH
THE END OF THIS WEEK...AS LOW AS -15C TO -20C LATE THU AND FRI.
THIS TRANSLATES TO DAYTIME HIGHS STRUGGLING TO REACH FREEZING INTO
NEXT WEEKEND.
NOTING ANOTHER LOW WORKING OUT OF THE SOUTHERN PLAINS STATES LATE
NEXT WEEK THAT WILL TRY TO MOVE NE WHILE ANOTHER H5 SHORT WAVE
MOVES ACROSS THE GREAT LAKES DURING THIS WEEKEND. RATHER WIDE
MODEL SPREAD IN HOW THIS EVOLVES ALONG THE EASTERN SEABOARD. MAY
SEE ANOTHER ROUND OF PRECIP SOMETIME DURING THIS TIMEFRAME. THIS
LOOKS TO LEAD INTO NEAR RECORD LEVEL TEMPS FOR NEXT SUNDAY INTO
EARLY NEXT WEEK.
BASED ON THE MODEL TRENDS FOR COLDER CONDITIONS...USED THE COLDER
HPC GUIDANCE FOR TEMPS/DEWPTS FOR THE MID-LATE WEEK. MOS GUIDANCE
TENDS TO RUN CLOSER TO CLIMO THIS FAR OUT. AS FOR POPS...LEANED
TOWARD A GENERAL BLEND OF THE 00Z GFS/12Z AND 00Z EC ALONG WITH
THEIR ENSEMBLES.
DETAILS...
TUESDAY...DRY CONDITIONS BETWEEN SYSTEMS EXPECTED DURING THE DAY
TUE...THOUGH CLOUDS WILL INCREASE. EXPECT CHANCE POPS TO MOVE INTO
THE CT VALLEY AND S COAST WELL AFTER MIDNIGHT.
WEDNESDAY...LOW PRES PASSES WELL SE OF BENCHMARK WHILE WEAK
REFLECTION TO UPPER SYSTEM MOVES ALONG THE CANADIAN BORDER.
QUESTION IS HOW MUCH QPF WORKS N FROM THE SOUTHERN STREAM SYSTEM.
ECMWF LOOKS TO BE VERY BULLISH ON THIS...WHILE NAM IS WEAKEST.
WENT WITH A MIDDLE OF THE ROAD SOLUTION...WITH QPF VALUES OF 0.1
INCHES ACROSS S NH TO 0.25 TO 0.4 INCHES ALONG THE S COAST...CAPE
COD AND THE ISLANDS. LOOKS LIKE TEMPS AND THERMAL PROFILES FAVOR
ALL SNOW...SO COULD SEE DECENT ACCUMULATING SNOWFALL ALONG THE S
COAST. SOMETHING TO MONITOR CLOSELY...ESPECIALLY IF MORE QPF WORKS
NW FROM THE SOUTHERN LOW. DOES LOOK LIKE THE PRECIP SHOULD BE
PROGRESSIVE...SO PRECIP SHOULD EXIT WED NIGHT. W-NW WINDS BECOME
GUSTY LATE WED NIGHT AS LOW EXITS
THURSDAY AND FRIDAY...LARGE HIGH PRES BUILDS OUT OF CENTRAL AND
WESTERN CANADA...BRINGING FIRST BATCH OF ARCTIC AIR TO THE REGION.
EXPECT DRY AND COLD CONDITIONS. BRISK NW WINDS IN PLACE...GUSTS UP
TO 25 TO 30 MPH ALONG THE COAST AND ESPECIALLY CAPE COD AND THE
ISLANDS.
SATURDAY-SUNDAY...MODEL SPREAD LENDS TO LOW CONFIDENCE WITH THE
POSSIBLE APPROACH OF LOW PRES OUT OF THE SE U.S. LOW CHANCE OF
MORE ACCUMULATING SNOWS DURING THIS TIMEFRAME. ANOTHER SHOT OF
NEAR RECORD COLD AIR FOR EARLY MARCH IS ALSO POSSIBLE.
&&
.AVIATION /05Z MONDAY THROUGH FRIDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH TUESDAY/...
THROUGH 12Z...MODERATE CONFIDENCE.
A FEW LIGHT SNOW/RAIN SHOWERS WILL SKIRT CT/RI/SE MA TERMINALS.
LITTLE IF ANY ACCUMULATION IS EXPECTED...BUT THE BEST CHANCE WILL
BE ACROSS SE MA. MAINLY VFR...BUT A SHORT PERIOD OF MVFR
CONDITIONS ARE POSSIBLE IN ANY SHOWERS.
TODAY AND TUESDAY...HIGH CONFIDENCE.
MAINLY VFR THROUGH THE PERIOD...BUT SOME LOW CU BETWEEN 030-060
POSSIBLE THROUGH DAYLIGHT HOURS ALONG WITH SOME LIGHT SNOW
SHOWERS POSSIBLE MAINLY W OF A IJD-ORH-EEN LINE TODAY. NW WINDS
GUSTING 25-30 KT AT TIMES TODAY...W WINDS GUST 20-25 KT ON TUE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...TUESDAY NIGHT THROUGH FRIDAY...
WEDNESDAY...AREAS OF MVFR-IFR CONDITIONS IN SNOW DURING THE DAY.
EXPECT IMPROVING CONDITIONS FROM W-E LATE WED INTO EARLY WED
NIGHT. VFR LATE. GUSTY W-NW WINDS DURING WED NIGHT...HIGHEST ALONG
COAST.
THURSDAY...VFR CONDITIONS. GUSTY NW WINDS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
TONIGHT...HIGH CONFIDENCE. SOUTHWEST WINDS SHIFT TO THE NORTHWEST
BEHIND A COLD FRONT. GUSTS UP TO 25 KNOTS MAY DEVELOP TOWARDS 12Z
AS COLD AIR ADVECTION GETS UNDERWAY. MAY ALSO SEE VISIBILITIES
REDUCED BRIEFLY TO BETWEEN 1 AND 3 MILES BETWEEN 6Z AND 12Z IN A
PERIOD OF LIGHT RAIN/SNOW SHOWERS.
MONDAY AND MONDAY NIGHT....HIGH CONFIDENCE. NORTHWEST WIND GUSTS OF
25 TO 30 KNOTS EXPECTED UNDER STRONG COLD ADVECTION YIELDING
EXCELLENT MIXING OVER THE OPEN WATERS. LOW PROBABILITY THAT A FEW
AREAS BRIEFLY SEE GUSTS NEAR 35 KNOTS...BUT IT WOULD BE TOO BRIEF
AND NOT WIDESPREAD ENOUGH FOR GALES. HOWEVER...SCA ADVISORIES ARE
POSTED FOR ALL WATERS MONDAY AND MONDAY NIGHT. LIGHT FREEZING
SPRAY IS EXPECTED TO DEVELOP MONDAY NIGHT UNDER STRONG COLD
ADVECTION.
OUTLOOK...TUESDAY THROUGH FRIDAY...
TUESDAY...W-NW WINDS GUSTING TO 25-30 KT WITH SEAS AOA 5
FT...DIMINISHING TUE NIGHT. VSBYS LOWER ON SOUTHERN WATERS AFTER
MIDNIGHT IN SNOW.
WEDNESDAY...NW WINDS INCREASE...GUSTING UP TO 30 KT ON THE OUTER
WATERS. SEAS BUILD UP TO 7 FT. LIGHT TO MODERATE FREEZING SPRAY
LIKELY WED NIGHT. VSBY RESTRICTIONS IN SNOW AND PATCHY FOG.
THURSDAY...NW WINDS GUSTING UP TO 30 KT THU...THEN SLOWLY DIMINISH
THU NIGHT. SEAS UP TO 8 FT WITH LIGHT TO MODERATE FREEZING SPRAY
LIKELY INTO THU NIGHT.
FRIDAY...WINDS AND SEAS DIMINISH.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 5 AM EST
TUESDAY FOR ANZ230>237-250-251-254>256.
&&
$$
SYNOPSIS...FRANK/EVT
NEAR TERM...FRANK/DOODY
SHORT TERM...FRANK
LONG TERM...EVT
AVIATION...DOODY/EVT
MARINE...FRANK/EVT
AREA FORECAST DISCUSSION
NWS MIAMI FL
246 PM EST MON FEB 24 2014
.DISCUSSION...
A WEAK COLD FRONT CURRENTLY DRAPED ACROSS NORTHERN FLORIDA IS
EXPECTED TO SLOWLY PUSH TO THE SOUTH THROUGH THE AFTERNOON AND
EVENING. AS IT DOES...A FEW SHOWERS AND POSSIBLY AN ISOLATED
THUNDERSTORM OR TWO MAY DEVELOP ACROSS MAINLY THE EAST COASTAL AREAS
ENHANCED BY A WEAK SEA BREEZE THAT MAY DEVELOP. LATEST HRRR WINDS
DEPICT A WEAK SEA BREEZE ALONG MAINLY THE BROWARD AND PALM BEACH
COUNTY COASTS.
MODELS DEPICT THE COLD FRONT AND ACCOMPANYING DEEPER MOISTURE FIELD
TO BECOME NEARLY STATIONARY ACROSS SOUTH FLORIDA THROUGH TUESDAY
WITH RAIN CHANCES REMAINING ALONG WITH LIGHT AND VARIABLE WINDS.
KEPT SLIGHT CHANCES FOR THUNDERSTORMS TUESDAY AFTERNOON ALONG THE
NORTHERN INTERIOR AND EAST COAST AS WELL WITH THE LINGERING BOUNDARY
IN THE AREA. BY TUESDAY NIGHT INTO EARLY WEDNESDAY...THE FRONT IS
EXPECTED TO BASICALLY WASH OUT IN PLACE. FLOW WILL THEN QUICKLY
BECOME SOUTHWEST AND INCREASE LATE WEDNESDAY OUT AHEAD OF ANOTHER
COLD FRONT POSITIONED ACROSS THE NORTHERN GULF OF MEXICO. THIS FRONT
LOOKS TO BE A BIT STRONGER THAN THE LAST ONE AND SHOULD PUSH THROUGH
SOUTH FLORIDA BY EARLY THURSDAY MORNING WITH BETTER CHANCES FOR
SHOWERS. DID NOT INCLUDE A THUNDER MENTION AT THIS TIME DUE TO THE
TIMING OF THE FRONT BEING DURING THE EARLY MORNING HOURS...ACCORDING
TO THE ECMWF. THE GFS SOLUTION IS A BIT SLOWER BRINGING THE FRONT
INTO SOUTH FLORIDA LATER IN THE AFTERNOON. IF THIS SOLUTION PANS
OUT...THE COMBINATION OF FRONTAL FORCING AND DAYTIME HEATING WOULD
YIELD THUNDERSTORM DEVELOPMENT. WILL NEED TO WATCH SUBSEQUENT MODEL
RUNS CLOSELY FOR TIMING CHANGES.
SHOWERS WILL LINGER THROUGH FRIDAY BEFORE DRY WEATHER RETURNS FOR
THE WEEKEND. UPPER RIDGING WILL THEN BUILD ACROSS THE AREA FROM THE
SOUTH KEEPING TEMPERATURES ABOVE NORMAL.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST ALTHOUGH THERE
COULD BE A BRIEF MVFR CIG/VSBY IN A FAST MOVING SHOWER AFT 20Z
THROUGH THIS EVENING. A COLD FRONT NORTH OF LAKE OKEECHOBEE WILL
KEEP SOUTH FLORIDA IN A GENERAL SW-W SURFACE WIND AND IT APPEARS
THE FLOW IS TOO STRONG TO ALLOW A SEA BREEZE TO DEVELOP ALONG THE
EAST COAST. SURFACE WIND BECOME L/V AFT 03Z.
&&
.MARINE...
WINDS OF 10 KNOTS OR LESS ARE EXPECTED TO CONTINUE ACROSS THE
REGIONAL WATERS WITH SEAS OF 2 FEET OR LESS. A COLD FRONT IS
FORECAST TO AFFECT THE REGIONAL WATERS EARLY THURSDAY WITH AN
INCREASE IN WINDS AND SEAS EXPECTED. HOWEVER...HAZARDOUS SEAS ARE
NOT FORECAST FOR THIS PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 67 81 63 82 / 20 30 10 20
FORT LAUDERDALE 69 82 66 82 / 20 30 10 20
MIAMI 69 83 67 83 / 20 30 10 20
NAPLES 64 79 62 80 / 10 20 - 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...10/CD
AVIATION/RADAR...30/KOB
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1013 PM EST TUE FEB 25 2014
.SYNOPSIS...
A GULF COAST LOW PRESSURE SYSTEM WILL MOVE EAST THROUGH GEORGIA
AND FLORIDA TONIGHT INTO WEDNESDAY BRINGING A CHANCE OF RAIN TO
OUR AREA. DRY AND COOLER WEATHER IS EXPECTED THURSDAY AND FRIDAY
WITH ANOTHER CHANCE OF RAIN EARLY SATURDAY WITH A FAST MOVING
SYSTEM.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
UPDATE...FORECAST REMAINS ON TRACK AS FRONT APPROACHES FROM THE
WEST. HAVE ADJUSTED POPS AND CLOUDS TO BETTER REPRESENT CURRENT
OBSERVATIONS WITH INCREASING CLOUDS AND CHANCES OF RAIN OVER THE
NEXT SEVERAL HOURS. BEST CHANCES OF RAIN WILL BE OVER THE SOUTHERN
MIDLANDS AND CSRA OVERNIGHT WITH RAIN SPREADING INTO THE CENTRAL
MIDLANDS DURING THE EARLY MORNING HOURS. RAINFALL AMOUNTS THROUGH
DAYBREAK ARE EXPECTED TO BE TWO TENTHS OF AN INCH OR LESS.
TEMPERATURES REMAIN ON TRACK FOR LOWER 40S FOR THE NORTHERN AND
WESTERN MIDLANDS WITH MID 40S TO AROUND 50 ELSEWHERE.
PREVIOUS DISCUSSION...CHANCES OF RAIN INCREASE LATE TONIGHT AS
BROAD UPPER TROUGH SINKS ACROSS THE GREAT LAKES AND OHIO VALLEY
REGION DRIVING A COLD FRONT THROUGH THE FORECAST AREA EARLY
WEDNESDAY MORNING BEFORE HIGH PRESSURE BUILDS IN AT THE SURFACE
BEHIND THE FRONT WEDNESDAY AFTERNOON. WESTERLY LOW LEVEL FLOW
AHEAD OF THE SHORTWAVE AND FRONT IS FORECAST TO BACK MORE
SOUTHWESTERLY THIS EVENING ALLOWING FOR ATMOSPHERIC MOISTURE TO
INCREASE WITH FLOW OFF THE WESTERN GULF OF MEXICO. HOWEVER...THE
TIME FRAME FOR SIGNIFICANT MOISTURE TO MOVE INTO THE REGION BEFORE
THE FRONT ARRIVES IS SHORT AND A LIMITING FACTOR DESPITE MODERATE
UPPER DYNAMICS ARRIVING AROUND THE 12Z TIME FRAME AS THE NORTHERN
AND SOUTHERN STREAM JETS COUPLE TO PROVIDE STRONG OMEGA AND UPWARD
VERTICAL MOTION OVER THE FORECAST AREA.
HAVE INCREASED POPS SLIGHTLY FROM PREVIOUS FORECAST...HIGHEST POPS
FROM THE CSRA ACROSS THE SOUTHEAST MIDLANDS LATE TONIGHT INTO
WEDNESDAY MORNING WITH A GRADIENT TO LOWER POPS TO THE NORTHWEST
WHERE MOISTURE WILL NOT BE AS GREAT. STILL FIGURE THE BEST TIME
FRAME FOR HIGHEST POPS WILL BE FROM 09Z-15Z WITH CHANCES OF RAIN
DECREASING FROM NORTHWEST TO SOUTHEAST THROUGH THE DAY WEDNESDAY.
LATEST 12Z NAM SOUNDINGS SUGGEST A MIX OF SNOW/RAIN POSSIBLE
ACROSS THE NORTHERN MIDLANDS WEDNESDAY MORNING WITH DEEP MOISTURE
INTO SNOW GROWTH ZONE AND NEAR SURFACE TEMPERATURES LIKELY IN THE
30S. CONFIDENCE IS LOW HOWEVER WITH LITTLE SUPPORT FROM
GFS...I.E. NO MOISTURE IN SNOW GROWTH ZONE. STILL THINK HIGHER
POPS WILL BE SOUTH OF THE NORTHERN MIDLANDS...BUT WILL INCLUDE
CHANCE SNOW/RAIN SHOWERS ACROSS NORTHERN LANCASTER COUNTY WHERE
PARTIAL THICKNESS SCHEMES FAVOR MIX.
CLOUDINESS LATE TONIGHT SHOULD KEEP TEMPERATURES FROM FALLING
SOMEWHAT...FAVOR WARMER MAV GUIDANCE. TEMPERATURES WILL BE MUCH
COOLER WEDNESDAY COMPARED TO TODAY WITH COLD ADVECTION TAKING
PLACE DURING THE DAY DESPITE SOME CLEARING SKIES BY AFTERNOON.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
WEDNESDAY NIGHT...THE LOW PRESSURE SYSTEM AND ALL ASSOCIATED
PRECIPITATION WILL BE WELL OFFSHORE BY WEDNESDAY NIGHT. COLD AIR
ADVECTION AND DECENT RADIATIONAL COOLING CONDITIONS WILL LEAD TO
BELOW NORMAL OVERNIGHT LOW TEMPERATURES...IN THE UPPER 20S NORTH
TO LOWER 30S SOUTH.
THURSDAY THROUGH THURSDAY NIGHT...A BROAD UPPER TROUGH WILL MOVE
OVER THE EASTERN CONUS ON THURSDAY PROMOTING WEST-NORTHWESTERLY
FLOW ALOFT. AT THE SURFACE...LOW PRESSURE OVER THE GREAT LAKES
REGION WILL BRING A DRY COLD FRONT THROUGH THE AREA. TEMPERATURES
WILL MAX OUT IN THE MID 50S TO NEAR 60 UNDER SUNNY SKIES. SURFACE
HIGH PRESSURE WILL SHIFT INTO THE OHIO VALLEY THURSDAY NIGHT
ALLOWING SURFACE WINDS TO ROTATE FROM WESTERLY TO NORTHEASTERLY.
MOSTLY CLEAR SKIES OVERNIGHT WILL SET THE STAGE FOR ANOTHER CHILLY
NIGHT WITH LOWS IN THE UPPER 20S TO NEAR 30.
FRIDAY THROUGH FRIDAY NIGHT...THE UPPER TROUGH WILL BE OFF THE
COAST BY FRIDAY WITH UPPER FLOW BECOMING ZONAL. SURFACE HIGH
PRESSURE WILL SHIFT OVER THE MID-ATLANTIC AND WEDGE INTO THE
FORECAST AREA FOR FRIDAY. TEMPERATURES WILL MAX OUT IN THE UPPER
40S NORTH TO MID 50S SOUTH. A WEAK SHORTWAVE TROUGH WILL BRING A
CHANCE OF PRECIPITATION FRIDAY NIGHT INTO EARLY SATURDAY. MOSTLY
CLOUDY SKIES OVERNIGHT WITH LOW TEMPERATURES ABOVE FREEZING IN THE
LOWER 30S TO NEAR 40.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
SHORTWAVE TROUGH WILL SHIFT EAST SATURDAY MORNING AS AN UPPER
RIDGE BUILDS OVER THE SOUTHEAST CONUS THROUGH SUNDAY WITH DRY
WEATHER EXPECTED. THE UPPER RIDGE WILL SHIFT EAST MONDAY AS A
TROUGH BUILDS OVER THE WESTERN CONUS. SIGNIFICANT TIMING
DIFFERENCES BETWEEN THE ECMWF AND GFS WITH THE NEXT SYSTEM
ARRIVING DURING THE MONDAY/TUESDAY TIME FRAME. THE ECMWF IS
A BIT QUICKER BRINGING THE SYSTEM THROUGH THAN THE GFS. BELOW
NORMAL MAX TEMPERATURES ON SATURDAY BUT OTHERWISE NEAR NORMAL
HIGHS IN THE 60S FOR THE REST OF THE EXTENDED. LATEST GUIDANCE HAS
CONTINUED TO TREND UP WITH TEMPERATURES FOR SUNDAY AND MONDAY.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD BUT CONFIDENCE IS
NOT HIGH.
A COLD FRONT WILL SINK SOUTHWARD AND THROUGH THE AREA TONIGHT.
NORTHERLY WINDS WILL DEVELOP BEHIND THE FRONT DURING THE EARLY
MORNING HOURS. EXPECT AN INCREASE IN CLOUDINESS AND THE DEVELOPMENT
OF RAIN OVER MOST OF THE AREA DURING THE EARLY MORNING HOURS MAINLY
ASSOCIATED WITH A COUPLED H25 JET PATTERN. THE LATEST HRRR SHOWED
COVERAGE UPSTREAM INCREASING AND MOVING INTO THE FORECAST AREA
AROUND 10Z. CONFIDENCE IS LOW WITH THE CEILING AND VISIBILITY
FORECAST BECAUSE OF MODEL INCONSISTENCY. THE NAM MOS INDICATED MVFR
OR IFR CEILINGS. THE GFS MOS AND LAMP PLUS SREF GUIDANCE INDICATED
CONTINUED VFR CEILINGS AND VISIBILITIES. THE 22Z HRRR INDICATED
MAINLY VFR CONDITIONS THROUGH 13Z. WE LEANED TOWARD THE MORE
OPTIMISTIC GUIDANCE BECAUSE OF THE H85 WESTERLY FLOW AND THE INITIAL
DRYNESS. ALSO...A LACK OF SIGNIFICANT ISENTROPIC LIFT SHOULD HELP
KEEP RAIN MAINLY LIGHT AND LIMIT ITS RESTRICTION TO VISIBILITY. THE
NAM AND GFS SHOW UPPER-LEVEL LIFT SHIFTING EAST OF THE AREA BETWEEN
16 AND 18Z. RAIN AND LINGERING LOWER CLOUDINESS SHOULD DIMINISH
DURING THIS TIME.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
828 PM MST TUE FEB 25 2014
.UPDATE...
ISSUED AT 811 PM MST TUE FEB 25 2014
JUST COMPLETED ANOTHER UPDATE. BAND OF SNOW IS HOLDING TOGETHER
VERY WELL DESPITE WHAT EARLIER MODEL OUTPUT SAID. STRONG MID LEVEL
FRONTOGENESIS AND UPPER LEVEL DEFORMATION IS WORKING ITS WAY
ACROSS. SNOW IS LIGHT PROBABLY DUE TO THE VERY POOR THETA-E LAPSE
RATES BUT STILL IT IS GOING TO SNOW. SO RAISED POPS TO 100 PERCENT
FOR THE REST OF THE EVENING AS THIS BAND WORKS ITS WAY SOUTH. WITH
THE SLOWER PROGRESSION OF THE BAND AND LINGERING DYNAMICS...HAVE
KEPT THE POPS GOING FOR A FEW HOURS AFTER 06Z. OTHERWISE MADE
SLIGHT ADJUSTMENTS IN THE TEMPERATURES.
UPDATE ISSUED AT 604 PM MST TUE FEB 25 2014
NICE BAND OF SNOW STILL OVER THE FAR NORTH AT THIS TIME WITH A
SLOW SHIFT SOUTH. SOME UNCERTAINTY HOW FAR SOUTH THIS BAND WILL
GET AND HOW FAST IT WILL DO IT. MESOSCALE GUIDANCE IS INDICATING
THAT THIS BAND WILL THIN AND WEAKEN AS IT MOVES SOUTH. DO HAVE A
RIGHT REAR QUADRANT OF JET AND STRONG PV ANOMALY MOVING IN FROM
THE NORTHWEST. SO AM THINKING THE BAND WILL HOLD TOGETHER.
SO UPPED UP POPS TO DEFINITE IN THE NORTH AND INCREASED THE
REMAINING PORTION OF THE AREA SLIGHTLY. ALSO MADE A SLIGHT
ADJUSTMENT TO THE WINDS BASED ON THE HRRR. LOOKS LIKE THERE WILL
BE A QUICK AND DRAMATIC CLEARING TREND AFTER THE SNOW ENDS. WINDS
WILL BE LIGHT FOR A LITTLE WHILE BEFORE PICKING UP LATER IN THE
NIGHT. AM THINKING THAT WE HAVE THE POTENTIAL TO BE MUCH COLDER
THAN CURRENTLY INDICATED. SO DID MAKE A SLIGHT ADJUSTMENT COLDER
FOR THE NIGHT AND WILL CONTINUE TO WATCH THE TRENDS CLOSELY AND
SEE WHAT THE NEWER GUIDANCE WILL TELL ME.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 113 PM MST TUE FEB 25 2014
MAIN FOCUS IN THE SHORT TERM WAS TEMPERATURES TODAY THROUGH
TOMORROW AND PRECIPITATION THIS AFTERNOON AND OVERNIGHT. HIGH
TEMPERATURES THIS AFTERNOON WERE ADJUSTED SINCE SOME LOCATIONS
REACHED THEIR HIGHS AROUND 18/19Z. AFTER 18Z COLDER AIR MOVED INTO
NORTHERN LOCATIONS WHERE TEMPERATURES HAVE REMAINED FAIRLY
STAGNANT OR INCREASED BY A DEGREE OR TWO. PORTIONS OF NORTHWEST
KANSAS AND EASTERN COLORADO ALONG AND SOUTH OF I-70 HAVE SEEN
TEMPERATURES IN THE UPPER TEENS TO MID 20S...BUT THIS APPEARS TO
BE THE PEAK OF TODAY`S HIGH TEMPERATURES AS THE COLDER AIR BEGINS
TO MOVE IN. SNOW HAS DEVELOPED OVER SOUTHWEST NEBRASKA AND IS
MOVING INTO NORTHWEST KANSAS ASSOCIATED WITH A FAIRLY STRONG AREA
OF FRONTOGENESIS. AS THE SHORTWAVE TROUGH IN MONTANA CONTINUES TO
PUSH SOUTHEAST AND THE STRONG AREA OF FRONTOGENESIS MOVES
SOUTHEAST AND THEN SOUTH...SNOWFALL WILL CONTINUE THROUGH THE
EVENING OVER MOST OF THE TRI-STATE REGION. THIS WILL BE A QUICK
MOVING WAVE AND THE GFS...NAM...AND RAP ALL SHOW PRECIPITATION OUT
OF THE FORECAST AREA BY 06Z. SINCE THE SYSTEM MOVES QUICKLY...SNOW
ACCUMULATIONS WILL ONLY BE AROUND HALF AN INCH SOUTH AND EAST TO 2
INCHES NORTH AND NORTHWEST. CLOUD COVER WILL STICK AROUND A LITTLE
AFTER 06Z...WITH MOST OF THE CWA BEING CLEAR BY 15Z. LOWS TONIGHT
WILL DROP DOWN INTO THE SINGLE DIGITS AS HIGH PRESSURE SETTLES
INTO THE CWA. NORTHERN AREAS WILL SEE LOWS AROUND 1 DEGREE ABOVE
ZERO TO NEAR ZERO WHILE AREAS FURTHER SOUTH AND WEST WILL SEE LOWS
AROUND 5 TO 10 ABOVE ZERO.
AS SURFACE HIGH PRESSURE SLIDES EAST-SOUTHEAST...ANOTHER SHORTWAVE
TROUGH WILL MOVE THROUGH. NO PRECIPITATION IS EXPECTED WITH THE
NEXT TROUGH SINCE DRIER AIR MOVES IN SO HAVE KEPT THE FORECAST DRY
FOR TOMORROW. TEMPERATURES WILL BE DIVIDED WITH HIGHS OVER THE
NORTHERN HALF OF THE TRI-STATE REGION IN THE UPPER 30S TO NEAR 40
AND THE SOUTHERN HALF/SOUTH-SOUTHWEST PORTION OF THE TRI-STATE
REGION IN THE LOW TO MID 40S. MODELS MAY HAVE BEEN PICKING UP ON
THE SNOW COVER IN THE NORTHERN AREA OF THE CWA WHICH IS WHY THE
TEMPERATURES THERE ARE A BIT LOWER. USED A COMBINATION OF CONSALL
AND SREF FOR TOMORROW`S TEMPERATURES TO TREND THEM DOWNWARD IN THE
SOUTHERN PORTIONS OF THE CWA SINCE THEY SEEMED TO BE TOO HIGH TO
ACCOUNT FOR ANY SNOWFALL THOSE AREAS MIGHT RECEIVE TONIGHT. WEST
TO SOUTHWEST WINDS TOMORROW COULD ALSO BECOME BREEZY AROUND 18Z AS
THE SHORTWAVE TROUGH PASSES THROUGH AND DAYTIME MIXING
INCREASES...BUT ONLY HAVE SUSTAINED WINDS AROUND 10 TO 20 MPH
WITH GUSTS AROUND 25 TO 30 MPH.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 224 AM MST TUE FEB 25 2014
WEDNESDAY NIGHT-THURSDAY...PROGRESSIVE SHORTWAVE RIDGE SHOULD HELP
KEEP DRY CONDITIONS IN PLACE THROUGH THESE PERIODS...WITH A SLIGHT
MODERATION OF THE AIR MASS OVER OUR CWA AS STATIONARY FRONT ALONG
FRONT RANGE LIFTS EAST WITH LEE TROUGH DEVELOPMENT. HIGH TEMPS
THURSDAY SHOULD BE NEAR NORMAL FOR WESTERN LOCATIONS (MID 40S TO
NEAR 50F)...WITH COOLER TEMPS IN THE MID/UPPER 30S FURTHER
NORTHEAST.
THURSDAY NIGHT-FRIDAY...NEXT IN A SERIES OF QUICK MOVING SHORTWAVE
TROUGHS WILL MOVE ACROSS THE REGION WITH ARCTIC AIR MASS DROPPING
BACK OVER WESTERN KS. BEST CHANCE FOR MEASURABLE SNOW APPEARS TO BE
LATE THURSDAY NIGHT THROUGH FRIDAY MORNING...WHEN MODELS ARE
ADVERTISING BETTER LARGE SCALE ASCENT. TIMING OF COLD FRONT IS A
LITTLE SLOWER WITH MAIN CAA FRIDAY AFTERNOON...WHICH MAY RESULT IN
QUITE A GRADIENT FROM THE NORTH-SOUTH OVER OUR CWA (LIKELY FALLING
TEMPS ACROSS THE NORTH).
FRIDAY NIGHT-TUESDAY...DESPITE DIFFERENCES IN THE LARGE SALE PATTERN
THROUGH THE EXTENDED PERIODS...MODELS HAVE COME INTO BETTER
AGREEMENT ON STUBBORN ARCTIC AIR MASS REMAINING IN PLACE OVER OUR
CWA...WITH ECMWF NOW TRENDING EVEN COLDER THAN THE LAST 3 RUNS OF
THE GFS. REGARDING LARGE SCALE PATTERN...ECMWF SHOWS MORE OF A
QUASI-ZONAL PATTERN WITH LOWER HEIGHTS SHIFTED SOUTH...WHILE GFS
SHOWS MORE OF A SPLIT FLOW PATTERN WITH THE NORTHERN STREAM HOLDING
MORE INFLUENCE OVER OUR CWA. EITHER SOLUTION FAVORS REINFORCING SHOTS
OF COLD ARCTIC AND AND PROLONGED BELOW NORMAL TEMPERATURES THROUGH AT
LEAST EARLY NEXT WEEK...ALONG WITH A SERIES OF QUICK MOVING
SHORTWAVES PASSING THROUGH THE REGION.
I TRENDED HIGH/LOW TEMPS DOWN TO ACCOUNT FOR THE COLDER PATTERN
CURRENT MODEL RUNS ARE ZEROING IN ON. EXPECTED CLOUD COVER
COMPLICATING HIGHS/LOWS...AND THERE ARE STILL DIFFERENCES BETWEEN
MODELS ON MAGNITUDE OF COOLING...SO I DID NOT FAVOR THE COLDEST
GUIDANCE DURING THIS UPDATE. THE TYPE OF AIR MASS CURRENTLY
ADVERTISED BY EVEN THE "WARMER" GFS WOULD SUPPORT OVERNIGHT LOWS IN
THE SINGLE DIGITS BELOW ZERO OVER PARTS OF OUR CWA DESPITE CLOUD
COVER (AND IF WE CLEAR OUT MUCH COLDER THAN THIS). CLOUDS COULD
LIMIT DAYTIME WARMING...AND ONGOING FORECAST OF TEENS-LOW 20S FOR
HIGHS MAY BE OPTIMISTIC. REGARDING PRECIP CHANCES...MANY OF THE
PERIODS IN THE EXTENDED HAVE SLIGHT CHANCE-CHANCE POPS...AND I DIDNT
SEE THE NEED TO REMOVE THESE BASED ON THE ACTIVE PATTERN ALOFT...AND
LINGERING BAROCLINIC ZONE ACROSS EASTERN COLORADO. BEST CHANCE FOR
MEASURABLE SNOW IN THESE PERIODS DOES APPEAR TO BE SAT-SAT NIGHT
WHEN A SLIGHTLY STRONGER SHORTWAVE TROUGH MOVES OUT OF THE SW US
ACROSS THE SOUTHERN PLAINS. THERE IS LITTLE IN THE WAY OF MOISTURE
RETURN/MOISTURE ADVECTION...SO ANY SNOWFALL WE SEE THROUGH THESE
PERIODS SHOULD BE ON THE LIGHT SIDE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 449 PM MST TUE FEB 25 2014
CURRENTLY LIGHT SNOW IS FALLING AT BOTH SITES. THIS IS A PART OF A
RATHER WIDE BAND WITH LOCAL/SMALL SCALE ENHANCED AREAS OF MODERATE
SNOWFALL EMBEDDED WITH THIS BIG BAND. FOR KMCK...IFR VISIBILITIES
TO MVFR CEILINGS WILL IMPROVE BY AROUND 02Z. AFTER THAT CONDITIONS
WILL BECOME VFR WITH LITTLE TO NO CLOUD COVER EXPECTED BY 05Z. AT
KGLD...THE SNOW IS JUST BEGINNING WHERE IT HAS STARTED TO END AT
KMCK. BY 02Z...IFR CONDITIONS WILL BE IN PLACE UNTIL AROUND 05Z.
CONDITIONS WILL TRANSITION FROM MVFR THEN VFR BY 08Z WITH LITTLE
TO NO CLOUD COVER AFTER THAT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...ALW/JSL
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
613 PM MST TUE FEB 25 2014
.UPDATE...
ISSUED AT 604 PM MST TUE FEB 25 2014
NICE BAND OF SNOW STILL OVER THE FAR NORTH AT THIS TIME WITH A
SLOW SHIFT SOUTH. SOME UNCERTAINTY HOW FAR SOUTH THIS BAND WILL
GET AND HOW FAST IT WILL DO IT. MESOSCALE GUIDANCE IS INDICATING
THAT THIS BAND WILL THIN AND WEAKEN AS IT MOVES SOUTH. DO HAVE A
RIGHT REAR QUADRANT OF JET AND STRONG PV ANOMALY MOVING IN FROM
THE NORTHWEST. SO AM THINKING THE BAND WILL HOLD TOGETHER.
SO UPPED UP POPS TO DEFINITE IN THE NORTH AND INCREASED THE
REMAINING PORTION OF THE AREA SLIGHTLY. ALSO MADE A SLIGHT
ADJUSTMENT TO THE WINDS BASED ON THE HRRR. LOOKS LIKE THERE WILL
BE A QUICK AND DRAMATIC CLEARING TREND AFTER THE SNOW ENDS. WINDS
WILL BE LIGHT FOR A LITTLE WHILE BEFORE PICKING UP LATER IN THE
NIGHT. AM THINKING THAT WE HAVE THE POTENTIAL TO BE MUCH COLDER
THAN CURRENTLY INDICATED. SO DID MAKE A SLIGHT ADJUSTMENT COLDER
FOR THE NIGHT AND WILL CONTINUE TO WATCH THE TRENDS CLOSELY AND
SEE WHAT THE NEWER GUIDANCE WILL TELL ME.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 113 PM MST TUE FEB 25 2014
MAIN FOCUS IN THE SHORT TERM WAS TEMPERATURES TODAY THROUGH
TOMORROW AND PRECIPITATION THIS AFTERNOON AND OVERNIGHT. HIGH
TEMPERATURES THIS AFTERNOON WERE ADJUSTED SINCE SOME LOCATIONS
REACHED THEIR HIGHS AROUND 18/19Z. AFTER 18Z COLDER AIR MOVED INTO
NORTHERN LOCATIONS WHERE TEMPERATURES HAVE REMAINED FAIRLY
STAGNANT OR INCREASED BY A DEGREE OR TWO. PORTIONS OF NORTHWEST
KANSAS AND EASTERN COLORADO ALONG AND SOUTH OF I-70 HAVE SEEN
TEMPERATURES IN THE UPPER TEENS TO MID 20S...BUT THIS APPEARS TO
BE THE PEAK OF TODAY`S HIGH TEMPERATURES AS THE COLDER AIR BEGINS
TO MOVE IN. SNOW HAS DEVELOPED OVER SOUTHWEST NEBRASKA AND IS
MOVING INTO NORTHWEST KANSAS ASSOCIATED WITH A FAIRLY STRONG AREA
OF FRONTOGENESIS. AS THE SHORTWAVE TROUGH IN MONTANA CONTINUES TO
PUSH SOUTHEAST AND THE STRONG AREA OF FRONTOGENESIS MOVES
SOUTHEAST AND THEN SOUTH...SNOWFALL WILL CONTINUE THROUGH THE
EVENING OVER MOST OF THE TRI-STATE REGION. THIS WILL BE A QUICK
MOVING WAVE AND THE GFS...NAM...AND RAP ALL SHOW PRECIPITATION OUT
OF THE FORECAST AREA BY 06Z. SINCE THE SYSTEM MOVES QUICKLY...SNOW
ACCUMULATIONS WILL ONLY BE AROUND HALF AN INCH SOUTH AND EAST TO 2
INCHES NORTH AND NORTHWEST. CLOUD COVER WILL STICK AROUND A LITTLE
AFTER 06Z...WITH MOST OF THE CWA BEING CLEAR BY 15Z. LOWS TONIGHT
WILL DROP DOWN INTO THE SINGLE DIGITS AS HIGH PRESSURE SETTLES
INTO THE CWA. NORTHERN AREAS WILL SEE LOWS AROUND 1 DEGREE ABOVE
ZERO TO NEAR ZERO WHILE AREAS FURTHER SOUTH AND WEST WILL SEE LOWS
AROUND 5 TO 10 ABOVE ZERO.
AS SURFACE HIGH PRESSURE SLIDES EAST-SOUTHEAST...ANOTHER SHORTWAVE
TROUGH WILL MOVE THROUGH. NO PRECIPITATION IS EXPECTED WITH THE
NEXT TROUGH SINCE DRIER AIR MOVES IN SO HAVE KEPT THE FORECAST DRY
FOR TOMORROW. TEMPERATURES WILL BE DIVIDED WITH HIGHS OVER THE
NORTHERN HALF OF THE TRI-STATE REGION IN THE UPPER 30S TO NEAR 40
AND THE SOUTHERN HALF/SOUTH-SOUTHWEST PORTION OF THE TRI-STATE
REGION IN THE LOW TO MID 40S. MODELS MAY HAVE BEEN PICKING UP ON
THE SNOW COVER IN THE NORTHERN AREA OF THE CWA WHICH IS WHY THE
TEMPERATURES THERE ARE A BIT LOWER. USED A COMBINATION OF CONSALL
AND SREF FOR TOMORROW`S TEMPERATURES TO TREND THEM DOWNWARD IN THE
SOUTHERN PORTIONS OF THE CWA SINCE THEY SEEMED TO BE TOO HIGH TO
ACCOUNT FOR ANY SNOWFALL THOSE AREAS MIGHT RECEIVE TONIGHT. WEST
TO SOUTHWEST WINDS TOMORROW COULD ALSO BECOME BREEZY AROUND 18Z AS
THE SHORTWAVE TROUGH PASSES THROUGH AND DAYTIME MIXING
INCREASES...BUT ONLY HAVE SUSTAINED WINDS AROUND 10 TO 20 MPH
WITH GUSTS AROUND 25 TO 30 MPH.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 224 AM MST TUE FEB 25 2014
WEDNESDAY NIGHT-THURSDAY...PROGRESSIVE SHORTWAVE RIDGE SHOULD HELP
KEEP DRY CONDITIONS IN PLACE THROUGH THESE PERIODS...WITH A SLIGHT
MODERATION OF THE AIR MASS OVER OUR CWA AS STATIONARY FRONT ALONG
FRONT RANGE LIFTS EAST WITH LEE TROUGH DEVELOPMENT. HIGH TEMPS
THURSDAY SHOULD BE NEAR NORMAL FOR WESTERN LOCATIONS (MID 40S TO
NEAR 50F)...WITH COOLER TEMPS IN THE MID/UPPER 30S FURTHER
NORTHEAST.
THURSDAY NIGHT-FRIDAY...NEXT IN A SERIES OF QUICK MOVING SHORTWAVE
TROUGHS WILL MOVE ACROSS THE REGION WITH ARCTIC AIR MASS DROPPING
BACK OVER WESTERN KS. BEST CHANCE FOR MEASURABLE SNOW APPEARS TO BE
LATE THURSDAY NIGHT THROUGH FRIDAY MORNING...WHEN MODELS ARE
ADVERTISING BETTER LARGE SCALE ASCENT. TIMING OF COLD FRONT IS A
LITTLE SLOWER WITH MAIN CAA FRIDAY AFTERNOON...WHICH MAY RESULT IN
QUITE A GRADIENT FROM THE NORTH-SOUTH OVER OUR CWA (LIKELY FALLING
TEMPS ACROSS THE NORTH).
FRIDAY NIGHT-TUESDAY...DESPITE DIFFERENCES IN THE LARGE SALE PATTERN
THROUGH THE EXTENDED PERIODS...MODELS HAVE COME INTO BETTER
AGREEMENT ON STUBBORN ARCTIC AIR MASS REMAINING IN PLACE OVER OUR
CWA...WITH ECMWF NOW TRENDING EVEN COLDER THAN THE LAST 3 RUNS OF
THE GFS. REGARDING LARGE SCALE PATTERN...ECMWF SHOWS MORE OF A
QUASI-ZONAL PATTERN WITH LOWER HEIGHTS SHIFTED SOUTH...WHILE GFS
SHOWS MORE OF A SPLIT FLOW PATTERN WITH THE NORTHERN STREAM HOLDING
MORE INFLUENCE OVER OUR CWA. EITHER SOLUTION FAVORS REINFORCING SHOTS
OF COLD ARCTIC AND AND PROLONGED BELOW NORMAL TEMPERATURES THROUGH AT
LEAST EARLY NEXT WEEK...ALONG WITH A SERIES OF QUICK MOVING
SHORTWAVES PASSING THROUGH THE REGION.
I TRENDED HIGH/LOW TEMPS DOWN TO ACCOUNT FOR THE COLDER PATTERN
CURRENT MODEL RUNS ARE ZEROING IN ON. EXPECTED CLOUD COVER
COMPLICATING HIGHS/LOWS...AND THERE ARE STILL DIFFERENCES BETWEEN
MODELS ON MAGNITUDE OF COOLING...SO I DID NOT FAVOR THE COLDEST
GUIDANCE DURING THIS UPDATE. THE TYPE OF AIR MASS CURRENTLY
ADVERTISED BY EVEN THE "WARMER" GFS WOULD SUPPORT OVERNIGHT LOWS IN
THE SINGLE DIGITS BELOW ZERO OVER PARTS OF OUR CWA DESPITE CLOUD
COVER (AND IF WE CLEAR OUT MUCH COLDER THAN THIS). CLOUDS COULD
LIMIT DAYTIME WARMING...AND ONGOING FORECAST OF TEENS-LOW 20S FOR
HIGHS MAY BE OPTIMISTIC. REGARDING PRECIP CHANCES...MANY OF THE
PERIODS IN THE EXTENDED HAVE SLIGHT CHANCE-CHANCE POPS...AND I DIDNT
SEE THE NEED TO REMOVE THESE BASED ON THE ACTIVE PATTERN ALOFT...AND
LINGERING BAROCLINIC ZONE ACROSS EASTERN COLORADO. BEST CHANCE FOR
MEASURABLE SNOW IN THESE PERIODS DOES APPEAR TO BE SAT-SAT NIGHT
WHEN A SLIGHTLY STRONGER SHORTWAVE TROUGH MOVES OUT OF THE SW US
ACROSS THE SOUTHERN PLAINS. THERE IS LITTLE IN THE WAY OF MOISTURE
RETURN/MOISTURE ADVECTION...SO ANY SNOWFALL WE SEE THROUGH THESE
PERIODS SHOULD BE ON THE LIGHT SIDE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 449 PM MST TUE FEB 25 2014
CURRENTLY LIGHT SNOW IS FALLING AT BOTH SITES. THIS IS A PART OF A
RATHER WIDE BAND WITH LOCAL/SMALL SCALE ENHANCED AREAS OF MODERATE
SNOWFALL EMBEDDED WITH THIS BIG BAND. FOR KMCK...IFR VISIBILITIES
TO MVFR CEILINGS WILL IMPROVE BY AROUND 02Z. AFTER THAT CONDITIONS
WILL BECOME VFR WITH LITTLE TO NO CLOUD COVER EXPECTED BY 05Z. AT
KGLD...THE SNOW IS JUST BEGINNING WHERE IT HAS STARTED TO END AT
KMCK. BY 02Z...IFR CONDITIONS WILL BE IN PLACE UNTIL AROUND 05Z.
CONDITIONS WILL TRANSITION FROM MVFR THEN VFR BY 08Z WITH LITTLE
TO NO CLOUD COVER AFTER THAT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...ALW/JSL
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
457 PM MST TUE FEB 25 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 113 PM MST TUE FEB 25 2014
MAIN FOCUS IN THE SHORT TERM WAS TEMPERATURES TODAY THROUGH
TOMORROW AND PRECIPITATION THIS AFTERNOON AND OVERNIGHT. HIGH
TEMPERATURES THIS AFTERNOON WERE ADJUSTED SINCE SOME LOCATIONS
REACHED THEIR HIGHS AROUND 18/19Z. AFTER 18Z COLDER AIR MOVED INTO
NORTHERN LOCATIONS WHERE TEMPERATURES HAVE REMAINED FAIRLY
STAGNANT OR INCREASED BY A DEGREE OR TWO. PORTIONS OF NORTHWEST
KANSAS AND EASTERN COLORADO ALONG AND SOUTH OF I-70 HAVE SEEN
TEMPERATURES IN THE UPPER TEENS TO MID 20S...BUT THIS APPEARS TO
BE THE PEAK OF TODAY`S HIGH TEMPERATURES AS THE COLDER AIR BEGINS
TO MOVE IN. SNOW HAS DEVELOPED OVER SOUTHWEST NEBRASKA AND IS
MOVING INTO NORTHWEST KANSAS ASSOCIATED WITH A FAIRLY STRONG AREA
OF FRONTOGENESIS. AS THE SHORTWAVE TROUGH IN MONTANA CONTINUES TO
PUSH SOUTHEAST AND THE STRONG AREA OF FRONTOGENESIS MOVES
SOUTHEAST AND THEN SOUTH...SNOWFALL WILL CONTINUE THROUGH THE
EVENING OVER MOST OF THE TRI-STATE REGION. THIS WILL BE A QUICK
MOVING WAVE AND THE GFS...NAM...AND RAP ALL SHOW PRECIPITATION OUT
OF THE FORECAST AREA BY 06Z. SINCE THE SYSTEM MOVES QUICKLY...SNOW
ACCUMULATIONS WILL ONLY BE AROUND HALF AN INCH SOUTH AND EAST TO 2
INCHES NORTH AND NORTHWEST. CLOUD COVER WILL STICK AROUND A LITTLE
AFTER 06Z...WITH MOST OF THE CWA BEING CLEAR BY 15Z. LOWS TONIGHT
WILL DROP DOWN INTO THE SINGLE DIGITS AS HIGH PRESSURE SETTLES
INTO THE CWA. NORTHERN AREAS WILL SEE LOWS AROUND 1 DEGREE ABOVE
ZERO TO NEAR ZERO WHILE AREAS FURTHER SOUTH AND WEST WILL SEE LOWS
AROUND 5 TO 10 ABOVE ZERO.
AS SURFACE HIGH PRESSURE SLIDES EAST-SOUTHEAST...ANOTHER SHORTWAVE
TROUGH WILL MOVE THROUGH. NO PRECIPITATION IS EXPECTED WITH THE
NEXT TROUGH SINCE DRIER AIR MOVES IN SO HAVE KEPT THE FORECAST DRY
FOR TOMORROW. TEMPERATURES WILL BE DIVIDED WITH HIGHS OVER THE
NORTHERN HALF OF THE TRI-STATE REGION IN THE UPPER 30S TO NEAR 40
AND THE SOUTHERN HALF/SOUTH-SOUTHWEST PORTION OF THE TRI-STATE
REGION IN THE LOW TO MID 40S. MODELS MAY HAVE BEEN PICKING UP ON
THE SNOW COVER IN THE NORTHERN AREA OF THE CWA WHICH IS WHY THE
TEMPERATURES THERE ARE A BIT LOWER. USED A COMBINATION OF CONSALL
AND SREF FOR TOMORROW`S TEMPERATURES TO TREND THEM DOWNWARD IN THE
SOUTHERN PORTIONS OF THE CWA SINCE THEY SEEMED TO BE TOO HIGH TO
ACCOUNT FOR ANY SNOWFALL THOSE AREAS MIGHT RECEIVE TONIGHT. WEST
TO SOUTHWEST WINDS TOMORROW COULD ALSO BECOME BREEZY AROUND 18Z AS
THE SHORTWAVE TROUGH PASSES THROUGH AND DAYTIME MIXING
INCREASES...BUT ONLY HAVE SUSTAINED WINDS AROUND 10 TO 20 MPH
WITH GUSTS AROUND 25 TO 30 MPH.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 224 AM MST TUE FEB 25 2014
WEDNESDAY NIGHT-THURSDAY...PROGRESSIVE SHORTWAVE RIDGE SHOULD HELP
KEEP DRY CONDITIONS IN PLACE THROUGH THESE PERIODS...WITH A SLIGHT
MODERATION OF THE AIR MASS OVER OUR CWA AS STATIONARY FRONT ALONG
FRONT RANGE LIFTS EAST WITH LEE TROUGH DEVELOPMENT. HIGH TEMPS
THURSDAY SHOULD BE NEAR NORMAL FOR WESTERN LOCATIONS (MID 40S TO
NEAR 50F)...WITH COOLER TEMPS IN THE MID/UPPER 30S FURTHER
NORTHEAST.
THURSDAY NIGHT-FRIDAY...NEXT IN A SERIES OF QUICK MOVING SHORTWAVE
TROUGHS WILL MOVE ACROSS THE REGION WITH ARCTIC AIR MASS DROPPING
BACK OVER WESTERN KS. BEST CHANCE FOR MEASURABLE SNOW APPEARS TO BE
LATE THURSDAY NIGHT THROUGH FRIDAY MORNING...WHEN MODELS ARE
ADVERTISING BETTER LARGE SCALE ASCENT. TIMING OF COLD FRONT IS A
LITTLE SLOWER WITH MAIN CAA FRIDAY AFTERNOON...WHICH MAY RESULT IN
QUITE A GRADIENT FROM THE NORTH-SOUTH OVER OUR CWA (LIKELY FALLING
TEMPS ACROSS THE NORTH).
FRIDAY NIGHT-TUESDAY...DESPITE DIFFERENCES IN THE LARGE SALE PATTERN
THROUGH THE EXTENDED PERIODS...MODELS HAVE COME INTO BETTER
AGREEMENT ON STUBBORN ARCTIC AIR MASS REMAINING IN PLACE OVER OUR
CWA...WITH ECMWF NOW TRENDING EVEN COLDER THAN THE LAST 3 RUNS OF
THE GFS. REGARDING LARGE SCALE PATTERN...ECMWF SHOWS MORE OF A
QUASI-ZONAL PATTERN WITH LOWER HEIGHTS SHIFTED SOUTH...WHILE GFS
SHOWS MORE OF A SPLIT FLOW PATTERN WITH THE NORTHERN STREAM HOLDING
MORE INFLUENCE OVER OUR CWA. EITHER SOLUTION FAVORS REINFORCING SHOTS
OF COLD ARCTIC AND AND PROLONGED BELOW NORMAL TEMPERATURES THROUGH AT
LEAST EARLY NEXT WEEK...ALONG WITH A SERIES OF QUICK MOVING
SHORTWAVES PASSING THROUGH THE REGION.
I TRENDED HIGH/LOW TEMPS DOWN TO ACCOUNT FOR THE COLDER PATTERN
CURRENT MODEL RUNS ARE ZEROING IN ON. EXPECTED CLOUD COVER
COMPLICATING HIGHS/LOWS...AND THERE ARE STILL DIFFERENCES BETWEEN
MODELS ON MAGNITUDE OF COOLING...SO I DID NOT FAVOR THE COLDEST
GUIDANCE DURING THIS UPDATE. THE TYPE OF AIR MASS CURRENTLY
ADVERTISED BY EVEN THE "WARMER" GFS WOULD SUPPORT OVERNIGHT LOWS IN
THE SINGLE DIGITS BELOW ZERO OVER PARTS OF OUR CWA DESPITE CLOUD
COVER (AND IF WE CLEAR OUT MUCH COLDER THAN THIS). CLOUDS COULD
LIMIT DAYTIME WARMING...AND ONGOING FORECAST OF TEENS-LOW 20S FOR
HIGHS MAY BE OPTIMISTIC. REGARDING PRECIP CHANCES...MANY OF THE
PERIODS IN THE EXTENDED HAVE SLIGHT CHANCE-CHANCE POPS...AND I DIDNT
SEE THE NEED TO REMOVE THESE BASED ON THE ACTIVE PATTERN ALOFT...AND
LINGERING BAROCLINIC ZONE ACROSS EASTERN COLORADO. BEST CHANCE FOR
MEASURABLE SNOW IN THESE PERIODS DOES APPEAR TO BE SAT-SAT NIGHT
WHEN A SLIGHTLY STRONGER SHORTWAVE TROUGH MOVES OUT OF THE SW US
ACROSS THE SOUTHERN PLAINS. THERE IS LITTLE IN THE WAY OF MOISTURE
RETURN/MOISTURE ADVECTION...SO ANY SNOWFALL WE SEE THROUGH THESE
PERIODS SHOULD BE ON THE LIGHT SIDE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 449 PM MST TUE FEB 25 2014
CURRENTLY LIGHT SNOW IS FALLING AT BOTH SITES. THIS IS A PART OF A
RATHER WIDE BAND WITH LOCAL/SMALL SCALE ENHANCED AREAS OF MODERATE
SNOWFALL EMBEDDED WITH THIS BIG BAND. FOR KMCK...IFR VISIBILITIES
TO MVFR CEILINGS WILL IMPROVE BY AROUND 02Z. AFTER THAT CONDITIONS
WILL BECOME VFR WITH LITTLE TO NO CLOUD COVER EXPECTED BY 05Z. AT
KGLD...THE SNOW IS JUST BEGINNING WHERE IT HAS STARTED TO END AT
KMCK. BY 02Z...IFR CONDITIONS WILL BE IN PLACE UNTIL AROUND 05Z.
CONDITIONS WILL TRANSITION FROM MVFR THEN VFR BY 08Z WITH LITTLE
TO NO CLOUD COVER AFTER THAT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...ALW/JSL
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
946 PM EST Tue Feb 25 2014
...Forecast Update...
Issued at 945 PM EST Tue Feb 25 2014
Certainly a challenging overnight forecast. Our expected upper-level
system is currently organizing across the Middle Mississippi Valley.
It will advect eastward through the overnight hours, with light snow
developing across the forecast area. The big issue is where the
heaviest snow will fall. The 18Z GFS develops the snow band from
Meade county eastward to Fayette and Clark counties. The 00Z NAM is
a little farther south by about one or two counties and produces the
heaviest snow farther east. The 00Z NAM seems to have shifted ever
so slightly northward when compared to it`s 18Z run. The latest RAP
(23Z at time of this writing) aligns pretty well with the GFS as far
as location. However, the RAP has been hit-and-miss on producing
accumulating snow until just the last few hourly cycles. The amounts
are certainly less than the GFS by about half. This is reasonable
given the current dewpoints across the area, as well as some dry air
aloft. Dewpoints in the middle to upper teens are common, with a few
sites at 20. Actual temperatures are ranging from the upper 20s to
lower 30s. So, there is some dry air to overcome, but the current
cloud deck overhead is working on that with some virga noticeable in
the radar returns and light snow just to our northwest in Illinois.
With all of this information, here is the current thinking. Believe
the likely area for snow accumulation of around an inch would be
along the Jefferson-Bullitt-Spencer county lines eastward to Fayette
and Clark counties. The Blue Grass region still stands the best
chance of accumulations at or slightly greater than one inch. The
21Z SREF probabilities of accumulations generally at or greater than
one inch supports this current thinking. Although these SREF probs
are fairly low, which likely means accumulations greater than an
inch will be localized.
This current thinking does not mean any adjustments to the advisory
are warranted at this time. The greatest accumulations still fall
within the advisory, and our Indiana counties are on tap to saturate
first (evident in upstream obs). The question remains if it will
snow long enough across our Indiana counties for adequate accums.
Still a tough call, but certainly not worth dropping the advisory at
this time since the snow is yet to fall. The next issue is whether
Meade and Hardin (perhaps Perry IN, Hancock, Breckinridge, and Larue
counties) should be added. Here, the NAM and RAP are currently
preferred. Some accumulation is possible, yet still believe the
totals closer to advisory criteria will be farther to the east. So,
the bottom line is the advisory will remain as is until at least
snow begins to fall and a better consensus can be made as to where
the main band will become established.
.SHORT TERM (Now through Wednesday Night)...
Issued at 230 PM EST Tue Feb 25 2014
Fast-moving upper disturbance diving out of the Upper Midwest will
be our main weather player in the near term, with the biggest
challenge being the southward extent and actual impact of
accumulating snows overnight.
Mid-level dry layer will erode quickly this evening, allowing snow
to break out mainly along the I-64 corridor before midnight. Models
are in uncanny agreement, all showing high-end chance POPs, but
given that this system could have impacts with just a trace of
liquid, will bump POPs into the likely category across southern IN
and the northern two thirds of KY. With a weak surface reflection,
this will be a quick-hitting system with a fairly narrow time window
to produce snow accumulations. Expect this system to traverse the
area between 03Z and 11Z Wednesday. QPF is quite modest, but temps
dropping quickly into the lower/mid-20s will support healthy snow to
liquid ratios. At this point the best chance for an inch of snow
appears to be along and north of a line from near Jasper, IN to
Bardstown to Richmond, KY. Given that temps will be cold enough to
limit the effectiveness of some road treatments, and travel impacts
will linger into the morning commute, will go with a low-end Winter
Weather Advisory for these areas.
Snow should exit the Bluegrass region just before daybreak on
Wednesday, giving way to clearing and cold conditions as Arctic high
pressure builds from the Upper Midwest. The window of strongest NW
winds appears to be narrowing, so wind chill values are not looking
quite as cold as previously advertised. Still could see a couple
hours of wind chills near zero along and north of I-64, with the
best chance of subzero chill factors over southern Indiana.
Afternoon temps will struggle into the mid/upper 20s, with some bust
potential across northern sections depending on how much snow falls
overnight.
This pattern is very progressive, so temps will not have a chance to
really bottom out Wednesday night as WSW return flow develops ahead
of the next reinforcing cold front.
.LONG TERM (Thursday through Tuesday)...
Issued at 250 PM EST Tue Feb 25 2014
A number of questions remain concerning temperatures and
precipitation types for the latter portion of the weekend, leading
to a quite challenging forecast.
The blocking ridge over our west coast will break down Thursday as a
deep longwave trough will finally undercut 500mb ridging over the Pacific
Northwest and bring widespread beneficial rains to California. This
energy will then cross the desert Southwest Friday and Saturday, and
will bring several bouts of precipitation to the Lower Ohio Valley
this weekend and Monday of next week.
Thursday through early Saturday...
Arctic air will build south of the Ohio River during the day
Thursday, in the wake of a cold front associated with a surface low
moving across the Great Lakes. Due to antecedent dry air, expect
only a few clouds, giving a mostly sunny day Thursday. Northwest
winds will pick up during the morning hours, bring pretty raw and
blustery conditions during the day. Highs Thursday may actually stay
cooler than Wednesday and will range from the lower 20s across
southern Indiana to the upper 20s near Tennessee.
Thursday night may become bitterly cold, and will likely be the
coldest night left in this "winter of our discontent". High pressure
centered over Indiana may provide light winds and clear skies, which
are optimal for good radiational cooling. Should these conditions
develop, lows will easily reach the single digits across southern
Indiana and the mid teens near Tennessee.
An initial flat disturbance will eject eastwards of the southern
plains and bring light precipitation to the area late Friday into
early Saturday. Both the GFS and NAM develop an inverted surface
trough that will extend from weak low pressure over the Texas
Panhandle along the Ohio River. Isentropic lift along and just north
of this feature will bring snow, or a rain snow mix to southern
Indiana and north central Kentucky, ending Saturday morning. Even
where precipitation is all snow, substantial accumulations are
unlikely with the expected light QPF.
Saturday through Monday...
The main upper level trough across the desert southwest will eject
into the Southern Plains late Sunday. A sharp inverted trough is
still expected to lie somewhere along the Ohio River and will
separate arctic air across the Great Lakes from a warm moist
spring-like airmass across the Tennessee Valley. Also, both surface
and 500mb ridging near Florida will ensure that rich Gulf moisture
will move north and east along this trough. After a cloudy and
seasonably cool day Saturday, widespread soaking precipitation will
spread northeast along this inverted trough towards the Commonwealth
by Sunday afternoon. A very sharp temperatures gradient will develop
along this trough, possibly right along or near the Ohio River. Highs
Sunday could easily vary from the mid 50s near Bowling Green to near
30 at Indianapolis. Substantial snow or a wintry mix is likely over
parts of Indiana while rain is now looking likely over much of the
Commonwealth. However, any rain/snow line will highly depend on
where exactly this surface trough ends up and may change in later
forecasts. Currently, the GFS operational model has rain as far
north as far southern Indiana, while the much colder 12z Tuesday
Canadian and the ECMWF models have snow all the way to just south of
the Ohio.
In any case, widespread precipitation will continue for much of
Sunday night, sagging to the southeast towards central Tennessee and
eastern Kentucky by early Monday. Many areas may receive an inch or
more of QPF with this system. It is also possible that initial rain
over Kentucky may change to snow early Monday as colder air filters
in on the back edge of any precipitation.
Monday night and Tuesday...
Arctic high pressure will build south once again late Monday,
bringing dry but cold temperatures Monday night and Tuesday.
&&
.AVIATION (00Z TAF Update)...
Updated at 637 PM EST Tue Feb 25 2014
A fast-moving upper wave will push across the Ohio Valley overnight,
and will be enough to squeeze out some light snow. Best chance is
04Z-08Z at SDF and 05Z-09Z at LEX. The latest data and upstream obs
indicate VFR conditions will prevail, however, the cig and vis may
drop to high-end MVFR on a temporary basis. With this snow band
expected to develop right over the region and varying guidance,
pin-pointing the timing of reduced conditions remains a bit
difficult. Northwest winds will increase to 10-15 knots during the
snow. As the system departs the area prior to daybreak Wednesday,
skies will become mostly clear/clear and northerly winds will
diminishing with the Arctic high building in.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY until 6 AM EST Wednesday FOR KYZ029>043-
045>049-056-057.
IN...WINTER WEATHER ADVISORY until 6 AM EST /5 AM CST/ Wednesday FOR
INZ076>079-083-084-090>092.
&&
$$
Update.........MJP
Short Term.....RAS
Long Term......JSD
Aviation.......MJP
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
338 PM EST MON FEB 24 2014
.SYNOPSIS...
HIGH PRESSURE BUILDS ACROSS THE AREA TONIGHT INTO TUESDAY. LOW
PRESSURE MOVES NORTHEAST ALONG THE MID ATLANTIC COAST LATE TUESDAY
NIGHT INTO WEDNESDAY. HIGH PRESSURE RETURNS FOR LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
LATEST SFC ANALYSIS REVEALS ~1029 MB LO PRES CENTERED OVR THE
MIDWEST AND A COLD FRNT PUSHING WELL OFF THE MID ATLANTIC CST.
TIGHT PRES GRADIENT BETWEEN THESE TWO FEATURES HAS LED TO WNW
WINDS GUSTING TO 20-30 MPH OVR THE MID ATLANTIC. THESE WINDS WILL
DIMINISH FOLLOWING SUNSET WHILE HI PRES BLDS IN FRM THE WEST.
EXPECT SOME INCREASING CLOUDS TNGT DUE TO INCREASING LO-LEVEL WAA
AND MOISTURE ADVECTION WITHIN THE PROGRESSIVE WLY FLOW ALOFT.
TEMPS WILL BE SLGTLY BLO NORMAL...WITH LOWS IN THE MID 20S TO LWR
30S.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
SHORT TERM PERIOD WILL FEATURE UPR-LEVEL LO PRES CENTERED ACROSS
CNTRL/ERN CANADA WITH CYCLONIC FLOW OVR THE ERN CONUS. APPROACHING
MID-LEVEL SHORTWAVE TROF AND INCREASING MOISTURE WILL LEAD TO
20-30% POPS OVR FAR NRN AREAS TUE. BEST FORCING ASSOCIATED WITH
THE TROF WILL PASS NORTH OF THE AREA. MODEL THICKNESSES AND SFC
TEMPS SUPPORT A RAIN/SNOW MIX...WITH JUST SNOW OVR NRN EDGES OF
THE FA. NO ACCUMULATIONS EXPECTED. OTHERWISE...EXPECT LGT WINDS
WITH A MSTLY CLOUDY SKY AND HIGH TEMPS RANGING FRM THE LO/MID 40S
NORTH TO UPR 40S/LWR 50S SOUTH.
FOR TUE NGT...ATTENTION TURNS TO AN APPROACHING (STRONGER)
SHORTWAVE TROF. COMBO OF DECENT MID/UPR-LEVEL FORCING AND MOISTURE
INCREASE WILL LEAD TO ANOTHER CHANCE FOR PRECIP ACROSS THE MID
ATLANTIC. LO TEMPS NEAR/BLO FREEZING IN MANY SPOTS AND CRASHING
THICKNESSES WILL ALLOW FOR THE CHANCE OF SNOW OVR MOST OF THE
AREA. DO THINK THAT SOME RAIN WILL BE MIXING IN OVR THE MID
SECTION OF THE FA...WITH MSTLY A RAIN EVENT FOR THE TIDEWATER/NE
NC. WITH THIS EVENT BEING SHORT IN DURATION AND TEMPS BEING
MARGINAL (I.E. MELTING ISSUES)...ONLY EXPECTING ACCUMULATIONS FOR
AREAS MAINLY NORTH OF RIC...THE NRN NECK AND THE LWR ERN SHORE. A
COATING TO ONE INCH IS PSBL. THE BULK OF THE PRECIP WILL FALL FRM
9-15Z WED...WITH CONDITIONS QUICKLY DRYING OUT FRM WEST TO EAST
WED AFTN AS SFC LO PRES DEVELOPS OFFSHORE AND PUSHES EWRD. HIGH
TEMPS IN THE MID 30S TO LWR 40S.
SFC HI PRES BLDS OVR THE SE US WED NGT. WITH CLEARING SKIES AND
LGT WINDS...TEMPS WILL FALL INTO THE UPR TEENS TO LWR 20S. BLO
NORMAL TEMPS CONTINUE INTO THU WITH A SUNNY SKY...HIGHS ONLY IN
THE 40S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
COLDER WITH BELOW NORMAL TEMPS. A SPLIT FLOW WILL LEAD TO QUICK
SYSTM MOVEMENTS AND PERIODIC PCPN CHCS THRU PRD. LEANED TOWARD THE
ECMWF WITH RESPECT TO SFC FEATURES.
CANADIAN HIGH PRESSURE KEEPS IT DRY BUT COLD FRIDAY. LOWS THURS
NIGHT IN THE L-M20S XCPT A FEW UPR TEENS NRMLY COLDER SPOTS. HIGHS
FRI M30S-L40S. NEXT IN A SERIES OF SRN STREAM S/W`S PROGGED TO TRACK
ACROSS THE SOUTHERN MID ATLNTC REGION FRI NIGHT AND SAT. LATEST MODEL
GUIDANCE WANTS TO SHEAR THE PCPN OUT AS IT CROSSES THE MTS FRI NIGHT
WHILE TRACKING AN AREA OF MSTR FROM SRN VA ACROSS THE CAROLINAS LATE
FRI NITE AND SAT MORN. UPSHOT HERE WILL BE YET ANTHR SYSTM WITH LGT
AMOUNTS OF QPF. P-TYPE ISSUES ARISE GIVEN SFC TMPS AOB FREEZING AND
CRITICAL THICKNESSES. WILL CARRY LOW CHC POPS FOR SNOW NWRN HALF OF
FA...A BUFFER ZONE OF SNOW/SLEET DOWN TO VA/NC BORDER WITH A RAIN
SLEET MIX ACROSS NC LATE FRI NITE. LOWS M20S-L30S. CHC LIQUID POPS
ACROSS SERN SCTNS OF FA WITH A BUFFER ZONE OF MIXED RAIN/SNOW FRTHR
NW SAT MORNING. PCPN ENDS MOST AREAS ARND NOON XCPT SOME LINGERING
RAIN CHCS AT THE COAST SAT AFTRN. HIGHS IN THE 40S.
ANTHR CANADIAN HIGH PRESSURE BUILDS INTO THE AREA SAT NIGHT THROUGH
SUNDAY NITE. DRY AND COLD WITH LOWS SAT NITE UPR TEENS-M20S. HIGHS
SUN M-U30S. LOWS SUN NIGHT IN THE 20S.
MODELS INDCTG ANTHR COMPLICATED SYSTM POISED TO MAKE A BEELINE FOR
THE MID ATLNTC RGN MONDAY. HIGH PRS TO THE NORTH ALLOWS FOR A WEDGE
TO SET UP AHEAD OF A MOISTURE LADEN SYSTM DVLPNG ACROSS THE DEEP
SOUTH. THE LOW PROGGED TO LIFT NORTH ACROSS THE RGN LATE MONDAY
ALONG WITH A COLD FRONTAL PASSAGE. MOISTURE PROGGED TO RIDE UP OVER
THE WEDGE PRODUCING A VARIETY OF WX ACROSS THE RGN SUN NITE AND MON
MORN WITH PCPN BCMG RAIN OVR ERN HALF OF FA MON. TO ERLY TO GET
SPECIFIC...BUT THIS SYSTM DOES BEAR WATCHING FOR THE PTNTL OF A
WINTER MIX OF PCPN SUNDAY NIGHT THROUGH MONDAY MORN. LOWS SUN NITE
25-30. HIGHS MON IN THE 30S AND 40S.
&&
.AVIATION /20Z MONDAY THROUGH SATURDAY/...
NW WIND SHOULD AVERAGE 8-12KT...WITH GUSTS TO AROUND 20KT AT
RIC/SBY. HIGH PRESSURE BUILDS ACROSS THE REGION TONIGHT AND MOVES
OFFSHORE TUESDAY.
A LOW PRESSURE SYSTEM DEVELOPS OFF THE MID ATLANTIC COAST TUESDAY
NIGHT AND WEDNESDAY. THIS HAS THE POTENTIAL TO BRING REDUCED
CIGS/VSBY IN A PERIOD OF -SN AT RIC/SBY AND A MIX OF -RA/SN AT
PHF/ORF/ECG...BEFORE POSSIBLY ENDING AS -SN AS FAR SE AS ECG.
ADDITIONALLY...A GUSTY NW WIND IS EXPECTED...ESPECIALLY NEAR THE
COAST. HIGH PRESSURE RETURNS WEDNESDAY AFTERNOON THROUGH FRIDAY.
&&
.MARINE...
WINDS STILL GUSTING TO ARND 25 KTS ACROSS NRN CSTL WTRS SO WILL KEEP
CURRENT SCA HEADLINE UP EXPECTING THE WINDS WILL DIMINISH THRU THE
EVE HOURS. RUC INDCTG A WEAK NRTH SURGE DOWN THE BAY THIS EVE BUT
EXPECT WINDS TO REMAIN BLO 20 KTS. OTW...HIGH PRESSURE BUILDS ACROSS
THE MARINE AREA TUE WITH A NORTH WIND BCMG SE AT SPEEDS BLO SCA LVLS.
LOW PRESSURE EXITS MOVES OFF THE CAROLINA COAST ERLY WED. STRONG CAA
BEHIND THIS SYSTM WILL LIKELY LEAD TO A PRD OF SCA`S FOR WINDS WED
AFTRN AND EVE. FLOW THEN BECOMES SW THURSDAY AS WEAK HIGH PRESSURE
MOVES OFF THE COAST. CANADIAN HIGH PRESSURE BUILDS SOUTH ACROSS THE
AREA FRI. DATA SUGGESTS ANTHR CAA SURGE ERLY FRI.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST TUESDAY FOR ANZ650.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR ANZ652.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MAS
SHORT TERM...MAS
LONG TERM...MPR
AVIATION...AJZ/DAP
MARINE...MPR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
636 PM EST TUE FEB 25 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 400 PM EST TUE FEB 25 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A FAMILIAR PATTERN
FEATURING A DEEP UPR TROF OVER ERN NAMERICA DOWNSTREAM OF A RDG
ALONG THE W COAST. SHRTWV EMBEDDED IN THE NW FLOW IS STREAKING SEWD
THRU ONTARIO JUST N OF LK SUP. COLD FNT ASSOCIATED WITH THIS
DISTURBANCE HAS PASSED THRU THE CWA...AND H85 TEMPS AS LO AS -25C TO
-28C ARE PUSHING INTO UPR MI IN THE LLVL W FLOW. ALTHOUGH THERE IS A
GOOD DEAL OF ICE ON LK SUP...AREAS OF OPEN WATER OVER THE FAR WRN LK
AND OVER THE SCENTRAL E OF THE KEWEENAW HAVE ALLOWED A GOOD DEAL OF
LK CLD/SOME -SHSN TO FORM IN THE LLVL CAD. THE LK CLDS/SHSN APPEAR
TO BE MOST WDSPRD OVER THE NE HALF OF THE AREA CLOSER TO THE SHRTWV
PASSING THRU ONTARIO/ACCOMANPANYING DYNAMIC SUPPORT AND DEEPER MSTR.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE LK EFFECT CLD/SHSN
TRENDS AND TEMPS/NEED FOR WIND CHILL HEADLINES.
LATE THIS AFTN/TNGT...AS THE H925 FLOW VEERS MORE TO THE NW THRU 00Z
IN THE WAKE OF SHRTWV PASSING BY TO THE N...EXPECT LK EFFECT
CLDS/SHSN TO SPREAD FARTHER TO THE S AND INLAND IN THE PRESENCE OF
LENGTHENING DAYTIME HEATING DESPITE DNVA/DEEP LYR QVECTOR DVGC IN
THE WAKE OF THE SHRTWV PASSAGE. H85 THERMAL TROF WITH TEMPS DOWN TO
-28/-29C IS FCST TO SHIFT THRU THE CWA BTWN 06Z-12Z AS THE LLVL FLOW
BACKS TO THE W BTWN SFC HI PRES SINKING TOWARD THE MID MS RIVER
VALLEY AND NEXT VIGOROUS SHRTWV DROPPING SEWD THRU SCENTRAL CANADA.
WITH A PERIOD OF LARGER SCALE QVECTOR DVGC...EXPECT CLRG OVER THE
INTERIOR...ALLOWING SFC TEMPS TO FALL WELL BLO ZERO AND INTO THE
TEENS BLO ZERO AT SOME PLACES UNDER DRY AIRMASS WITH PWAT UNDER 0.10
INCH. ALTHOUGH THERE ARE QUESTIONS AS TO WHETHER SFC WINDS WL
CONSISTENTLY SATISFY THE 10 MPH SPEED THRESHOLD FOR A WIND CHILL
ADVY...PLAN TO ISSUE AN ADVY FOR THE COLDER NW HALF OF THE CWA WITH
FAIRLY SHARP PRES GRADIENT/H925 WINDS IN THE 20-30KT RANGE UNDER H85
THERMAL TROF ENHANCING MIXING. LK EFFECT CLDS/-SHSN WL SHIFT FM THE
NW WIND SN BELTS BACK INTO AREAS IMPACTED BY W WINDS LATE TNGT.
ABSENCE OF DGZ WITHIN VERY COLD AIRMASS AND ICE COVER WL LIMIT SN
ACCUMS.
WED...AREA OF DEEP LYR QVECTOR CNVGC IN ADVANCE OF SHRTWV/SFC LO
DIGGING SEWD THRU NW ONTARIO WL OVERSPREAD UPR MI NW-SE BY EARLY
AFTN. IN THE ABSENCE OF ANY SGNFT MSTR INFLOW...SUSPECT DRYNESS OF
ANTECEDENT AIRMASS WL BE A SGNFT IMPEDIMENT TO OUTBRREAK OF PCPN. AS
THE FLOW SHIFTS TO THE SW...THERE IS POTENTIAL FOR SOME LK
MOISTENING/ENHANCEMENT OFF OF LK MI. BUT EXTENSIVE/GROWING ICE COVER
OVER THE N HALF OF LK MI WL TEND TO MITIGATE THIS IMPACT. TENDED
TOWARD THE HIER CHC/LIKELY POPS OVER THE NE HALF OF THE CWA TOWARD
SHARPER ISENTROPIC ASCENT ON THE 270K SFC /NEAR H7/ AND ALSO LATE IN
THE DAY OVER THE W WITH EXPECTED ARRIVAL OF ENHANCED LLVL CNVGC
ASSOCIATED WITH COLD FNT ATTENDANT TO CLIPPER LO REACHING NE LK SUP
BY 00Z THU.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 409 PM EST TUE FEB 25 2014
ANOTHER WAVE FROM THE TROUGH OVER EASTERN CANADA WILL BE QUICKLY
DIVING SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION ON WEDNESDAY
EVENING. A 1000MB LOW WILL BE DROPPING SOUTHEAST ACROSS
NORTHEASTERN LAKE SUPERIOR AND THEN INTENSIFYING TO 995MB AS IT
MOVES OVER THE GEORGIAN BAY BY 12Z THURSDAY. MODELS CONTINUE TO BE
FAIRLY CONSISTENT WITH THE TRACK/INTENSITY/TIMING OF THE
LOW...WHICH LENDS CONFIDENCE TO THE FORECAST...ESPECIALLY WITH THE
WINDS. THE COMBINATION OF COLD AIR ADVECTION AND STRONG PRESSURE
RISES (10MB/6HR) BEHIND THE LOW BETWEEN 06Z AND 15Z THURSDAY SHOULD
LEAD TO A PERIOD OF GUSTY WINDS ACROSS MUCH OF UPPER MICHIGAN. THE
WORST CONDITIONS WILL BE IN THE EXPOSED AREAS NEAR LAKE SUPERIOR
FROM ONTONAGON EASTWARD. OVER THE KEWEENAW AND THEN AREAS FROM
MARQUETTE EASTWARD...MODELS ARE SHOWING 925MB WINDS IN THE 35-45KT
RANGE WITH THE HIGHEST VALUES FROM THE TIP OF THE KEWEENAW TO ALGER
COUNTY. WITH THE PASSAGE OF THE COLD FRONT ON WEDNESDAY
EVENING...THINK THERE WILL BE A PERIOD OF LIGHT SNOW BUT
ACCUMULATIONS SHOULD BE LESS THAN .5IN IN MOST AREAS. ALTHOUGH THIS
WON/T AMOUNT TO MUCH...IT WILL LEAD TO SOME BLOWING/DRIFTING SNOW.
THE WORST CONDITIONS WILL AGAIN BE OVER THE KEWEENAW...WHICH
ALREADY HAS LARGE MOUNDS/DRIFTS ON THE EDGES OF ROADWAYS THAT SHOULD
EASILY REDEVELOP OVER THE ROADS WITH THE STRONG WINDS AND A LITTLE
BIT OF SNOW. FARTHER EAST...THERE HAS BEEN SOME LIGHT LAKE EFFECT
AND WITH ICE REDEVELOPING EAST OF THE KEWEENAW THERE SHOULD BE AN
OPEN/FLAT AREA FOR THE SNOW TO MOVE ACROSS AND IMPACT ALGER COUNTY.
WITH M-28 EXPOSED TO THE LAKE EAST AND BETTER ICE COVERAGE EAST OF
SHOT POINT...THINK THERE WILL BE A GOOD POTENTIAL FOR
BLOWING/DRIFTING SNOW CAUSING ISSUES ON THE ROAD THROUGH MUNISING.
THE COLD AIR RECENTLY HAS LEAD TO ICE SPREADING OVER THE OPEN AREAS
THE DEVELOPED A COUPLE DAYS AGO AND FORTUNATELY...THINK THIS WILL
LIMIT THE AMOUNT OF LAKE EFFECT WITH THE NORTHWEST WINDS BEHIND THE
LOW WED NIGHT INTO THURSDAY. ALSO...WITH A HIGH PRESSURE RIDGE
QUICKLY MOVING IN TO THE U.P. FROM WEST TO EAST THURSDAY MORNING
INTO THURSDAY AFTERNOON...IT SHOULD DO TWO THINGS. BRING DRIER AIR
AND LIMIT THE ANY LAKE EFFECT INTENSITY AND ALSO LEAD TO QUICKLY
WEAKENING WINDS.
WITH THE PRECIPITATION...WIND...AND ALSO COLD
TEMPERATURES...HEADLINES WILL LIKELY BE NEEDED OVER ALL OF UPPER
MICHIGAN WEDNESDAY NIGHT INTO THURSDAY MORNING. WIND CHILL
TEMPERATURES ARE CURRENTLY FORECAST IN THE -25 TO -40 DEGREE RANGE
AND PUTS SOME NORTHERN AREAS ON BORDERLINE WIND CHILL WARNING
CRITERIA. OTHERWISE...THINK THE ENTIRE U.P. WOULD NEED A WIND CHILL
ADVISORY. SECOND...WITH THE REDUCED VISIBILITIES NEAR LAKE SUPERIOR
FROM FALLING/BLOWING/DRIFTING SNOW...WILL LIKELY NEED AT LEAST A
WINTER WEATHER ADVISORY FOR THE KEWEENAW PENINSULA AND ALGER COUNTY.
THE WINDS AND VISIBILITIES WILL LIKELY PRODUCE BRIEF PERIODS OF
BLIZZARD CONDITIONS IN THE KEWEENAW...BUT WITH THE MODELS ONLY
SHOWING A PEAK PERIOD OF 6HRS OF THE WORST WINDS AND IT LARGELY
BEING OVERNIGHT BEFORE QUICKLY DIMINISHING...FEEL IMPACT WON/T
BE AS BAD AS PREVIOUS EVENT AND WON/T ISSUE A BLIZZARD WATCH. WINDS
WILL LIKELY BE WORSE OVER ALGER COUNTY...BUT THERE IS MORE
UNCERTAINTY WITH THE VISIBILITY ASPECT OF THE CRITERIA WITH THE
LIMITED SNOWFALL SINCE THE RA/FZRA FROM LAST THURSDAY NIGHT (ALONG
WITH GENERALLY NEW ICE UPSTREAM ON LAKE SUPERIOR AND LIMITED SNOW
COVER). THUS...THINK ANY BLIZZARD CONDITIONS WOULD BE PATCHY AND
WOULD SUPPORT MORE OF A WINTER WX ADVISORY.
STILL LOOKS TO BE A RECORD BREAKING COLD DAY ON THURSDAY...WITH
MODELS KEEPING MUCH OF THE AREA AROUND OR BELOW FREEZING FOR HIGHS.
THAT SEEMS PRETTY REASONABLE WITH THE POCKET OF COLD 850MB TEMPS
(-30C) DIRECTLY OVER THE AREA. THIS IS SIMILAR TO 850MB TEMPS FROM
JANUARY 27TH AND HIGHS THAT DAY WERE IN THE SINGLE DIGITS BELOW
ZERO OVER THE WEST AND AT OR JUST ABOVE FREEZING OVER THE EAST. AS
MENTIONED YESTERDAY...ALL-TIME COLDEST HIGH TEMP RECORDS FOR FEB
27TH ARE GENERALLY IN THE MID SINGLE DIGITS ABOVE ZERO (WITH AT
LEAST 6 DATING BACK BEFORE 1925). WITH COLD AIR IN PLACE AND A HIGH
PRESSURE RIDGE PRODUCING LIGHT WINDS...EXPECT A VERY COLD NIGHT
THURSDAY NIGHT AND WILL CONTINUE TO GO WITH THE LOW END OF GUIDANCE
WHICH PLACES MUCH OF THE AREA BETWEEN -15 AND -30 BELOW. THIS
ALSO HAS THE POTENTIAL FOR BEING RECORD LOWS AT SEVERAL
LOCATIONS...AS LONG AS THE HIGH CLOUDS DON/T COME IN TOO QUICKLY
FROM THE SOUTHWEST.
THE HIGH PRESSURE RIDGE WILL SLIDE EAST ON FRIDAY AS ANOTHER
SHORTWAVE ROUNDING THE EASTERN CANADA TROUGH APPROACHES. A WEAK
INVERTED TROUGH (FROM A LOW IN THE SOUTHERN PLAINS) WILL SLIDE
ACROSS THE AREA ON FRIDAY EVENING AND BRING THE POTENTIAL FOR LIGHT
SNOW. IT DOES APPEAR TO BE OUT AHEAD OF THE MAIN FORCING FROM THE
SHORTWAVE...SO UPPER LEVEL SUPPORT WILL BE LIMITED AND KEEP SNOW
ACCUMULATIONS GENERALLY UNDER AN INCH. MODELS VARY ON HOW MUCH COLD
AIR SPILLS IN BEHIND THIS TROUGH...BUT IT STILL LOOKS LIKE HIGHS ON
SATURDAY WILL BE WELL BELOW NORMAL AND AT OR JUST ABOVE ZERO. THERE
IS ALSO CONCERN FOR LAKE EFFECT SNOW WITH THE COLD AIR PRESENT...BUT
WOULD EXPECT MUCH OF THE LAKE TO BE FROZEN OVER WITH THE COLD AIR
OVER THE PREVIOUS COUPLE OF DAYS AND LIGHT WINDS THURSDAY NIGHT.
THEREFORE...WILL KEEP POPS FOR SATURDAY IN THE SLIGHT CHANCE AND LOW
END CHANCE CATEGORY FOR LOCATIONS NEAR LAKE SUPERIOR. HIGH PRESSURE
BUILDING IN SATURDAY NIGHT AND REMAINING INTO SUNDAY SHOULD LEAD TO
DRY CONDITIONS.
FOR THE FIRST PART OF NEXT WEEK...THE UPPER TROUGH IN EASTERN
CANADA DOES LOOK TO WEAKEN SOME AND BEGIN TO PULL NORTHEAST TOWARDS
THE END OF THE WORK WEEK. OUR CLOSE PROXIMITY TO THIS TROUGH WILL
KEEP THE MAIN STORM TRACK AND WARMER AIR WELL TO THE SOUTH OF THE
AREA...BUT WE COULD STILL SEE WEAK WAVES SLIDING THROUGH. WOULD
EXPECT LAKE SUPERIOR TO BE NEARLY ICE COVERED...SO WILL LIMIT ANY
MENTION OF LAKE EFFECT POPS TO SLIGHT CHANCES AT MOST. AS FOR
TEMPS...SHOULD SEE A SLOW/GRADUAL WARMING TREND THROUGH THE WORK
WEEK...BUT TEMPS WILL STILL BE WELL BELOW NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 634 PM EST TUE FEB 25 2014
WINDS BEGINNING TO ABATE SLIGHTLY AT ALL THREE TAF SITES THIS
EVENING. WINDS ARE TO GRADUALLY DIMINISH OVERNIGHT AS THEY BACK TO
THE SSW/SW BY DAYBREAK...AND THEN WILL PICK UP AS THE MORNING
PROGRESSES...WITH GUSTS TO 22-23KTS COMMON DURING THE LATE MORNING
AND AFTERNOON HOURS. AT KCMX...LIFR/IFR VISIBILITIES DUE TO BRIEF
LES SNOW BANDS AND GUSTY WINDS CHANNELED THROUGH THE TERRAIN THERE
WILL EVENTUALLY IMPROVE AFTER 6Z AS WINDS DIMINISH AND DRIER AIR
WORKING IN FROM THE WEST DIMINISHES LES. OTHERWISE...MVFR/VFR
CONDITIONS PREVAIL AT KIWD AND KSAW WITH MVFR DEVELOPING AT KCMX BY
9Z...AND WILL CONTINUE THROUGH THE FORECAST. IFR VISIBILITY
CONDITIONS MAY REDEVELOP AT KCMX WEDNESDAY AFTERNOON AS WINDS SHIFT
BACK TO THE WEST AND PICK UP AND LES REDEVELOPS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 PM EST TUE FEB 25 2014
NW WINDS UP TO 25-30 KTS LATE TODAY UNDER SHARP PRES GRADIENT
BETWEEN SFC HI OVER THE NCENTRAL PLAINS AND LO PRES IN EASTERN
ONTARIO WILL SLOWLY BACK TO THE SW ON WED AS THE HI MOVES INTO THE
MID MS RIVER VALLEY AND ANOTHER LO PRES SYSTEM DIVES SE INTO NW
ONTARIO. THERE MAY BE SOME GALE FORCE GUSTS TO 35 KTS OVER THE W
HALF OF THE LAKE WHERE FUNNELING OF THIS FLOW RESULTS IN SPEED
ENHANCEMENT. ONCE THE LO SHIFTS TO THE E OF THE LAKE ON WED NIGHT
AS THE PRES GRADIENT TIGHTENS AGAIN E OF HI PRES MOVING INTO THE
NORTHERN PLAINS...N GALES UP TO 35-45 KTS WILL DEVELOP OVER THE
ENTIRE LAKE. THE CLOSER APPROACH OF THE HI CENTER AND WEAKER PRES
GRADIENT WILL CAUSE THE GALES TO DIMINISH W TO E ON THU. ISSUED A
GALE WATCH FOR THE ENTIRE LAKE. EXPECT WINDS UNDER 25 KTS THE REST
OF THE FORECAST PERIOD WITH A RELATIVELY WEAK PRES GRADIENT
DOMINATING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY FROM MIDNIGHT EST /11 PM CST/ TONIGHT TO 10
AM EST /9 AM CST/ WEDNESDAY FOR MIZ001>005-009>011-084.
LAKE SUPERIOR...
GALE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY AFTERNOON
FOR LSZ243>245-248>251-264>267.
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR
LSZ162-240>242-263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...RJT
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
407 PM EST MON FEB 24 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 357 PM EST MON FEB 24 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PERSISTENT...COLD
NW FLOW DOMINATING THE GREAT LKS BTWN RDG ALONG THE W COAST AND
CLOSED LO OVER QUEBEC/TROF IN ERN NAMERICA. COMBINATION OF SHRTWV
EMBEDDED IN NW FLOW ALF...DEEPER MSTR SHOWN ON THE 12Z INL RAOB...
H85 TEMPS IN THE -18C TO -21C RANGE AND SOME OPEN WATER ON LK SUP
HAS RESULTED IN SOME GENERALLY LGT LES IN AREAS FAVORED BY THE LLVL
WNW FLOW. OVER THE INTERIOR...SOME DIURNAL CU/SC HAVE DVLPD IN
RATHER MOIST AIRMASS WITH INCRSG SUN ANGLE CAUSING SOME LLVL
DESTABILIZATION. BTWN THE SHRTWV MOVING THRU THE UPR LKS EARLY THIS
AFTN AND ANOTHER STRONGER DISTURBANCE STRETCHING FM NEAR LK WINNIPEG
INTO THE NRN PLAINS/ACCOMPANYING -SN MOVING THRU THE DAKOTAS...
SHRTWV RDG/AXIS OF DRIER MID LVL AIR IS BRINGING GENERALLY MOSUNNY
WX TO MUCH OF MN EXCEPT THE ARROWHEAD. YET ANOTHER SHRTWV IS
DROPPING SWD FM THE NW TERRITORIES OF CANADA INTO NRN SASKATCHEWAN/
MANITOBA.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE LES TRENDS AND TEMPS
ASSOCIATED WITH THE STEADY PARADE OF DISTURBANCES EMBEDDED IN NW
FLOW ALF.
TNGT...WITH APRCH AND PASSAGE OF SHRTWV RDG LATER THIS AFTN AND THIS
EVNG/ACCOMPANYING DEEP LYR QVECTOR DVGC AND SUBSIDENCE...EXPECT
LINGERING LES TO AT LEAST DIMINISH IN INTENSITY/COVERAGE FOR A TIME.
BUT AS SHRTWV NOW MOVING INTO THE NRN PLAINS SHIFTS TO THE SE
TNGT...AREA OF ACCOMPANYING DEEP LYR QVECTOR CNVGC/MORE MSTR AND SFC
COLD FNT ARE FCST TO IMPACT THE AREA MAINLY AFT MIDNGT. ALTHOUGH ALL
MODELS SHOW THE ACCOMPANYING SYNOPTIC SCALE PCPN PASSING TO THE S OF
THE CWA CLOSER TO CORE OF UPR DVGC ON CYC SIDE OF H3 JET MAX...
EXPECT AN INCRS IN LES COVERAGE NEAR LK SUP OVERNGT. TEMPS COULD
FALL OFF QUICKLY THIS EVNG OVER AT LEAST THE INTERIOR NEAR THE WI
BORDER AS AXIS OF DRIER AIR AT LEAST BRIEFLY MOVES OVHD BEFORE
THICKER CLDS ASSOCIATED WITH DISTURBANCE NEAR LK WINNIPEG ARRIVE
LATER.
TUE...WHILE THERE MAY BE SOME MID LVL DRYING/SUBSIDENCE EARLY ON TUE
WITH A PERIOD OF QVECTOR DVGC FOLLOWING THE DEPARTING DISTURBANCE...
SHRTWV NOW DROPPING S INTO SASKATCHEWAN/MANITOBA IS FCST TO BRING A
RETRUN OF MORE DYNAMIC SUPPORT/SOME DEEPER MSTR BY THE AFTN...
ESPECIALLY OVER THE NE HALF OF THE CWA. SO EXPECT INCRSG LES POPS
AGAIN IN THE WNW WIND SN BELTS NEAR THE LK. GIVEN H85 TEMPS FALLING
AOB -25C BY LATE IN THE DAY CAUSING THE NEAR ELIMINATION OF THE DGZ
AS WELL AS CONSIDERABLE ICE COVER OVER LK SUP...EXPECT SN AMOUNTS TO
BE RELATIVELY LIGHT. TUE WL BE ANOTHER UNSEASONABLY COLD DAY. TENDED
TOWARD THE LO END OF GUIDANCE FOR MAX TEMPS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 406 PM EST MON FEB 24 2014
THE FIRST IN A SERIES OF UPPER LEVEL DISTURBANCES THAT WILL BRING
COLDER AIR TO THE AREA WILL BE SWEEPING ACROSS UPPER MICHIGAN
TUESDAY AFTERNOON AND EARLY TUESDAY EVENING. THIS SHORTWAVE WILL
USHER IN SLIGHTLY COLDER 850MB TEMPS ON TUESDAY NIGHT (-28C) AND
WITH WINDS OUT OF THE NORTHWEST...WOULD EXPECT AT LEAST A BRIEF
PERIOD OF LIGHT TO MODERATE LAKE EFFECT SNOW IN THE NORTHWEST WINDS
SNOW BELTS DURING THE EVENING. BUT MODELS ARE SHOWING DRY AIR ABOVE
850MB MOVING IN QUICKLY AFTER 06Z WEDNESDAY...SO THAT SHOULD CUT OUT
THE INTENSITY HEADING INTO THE OVERNIGHT HOURS. GETTING A GOOD
HANDLE ON ICE COVER OVER THE WESTERN LAKE TODAY...WITH OPEN WATER
GENERALLY NORTHWEST OF A LINE FROM THE APOSTLE ISLANDS TO TERRACE
BAY ONTARIO. THAT GAP OF 30-40MI IS PLENTY TO SUPPORT LAKE EFFECT
CLOUDS AND SNOW...WHICH HAS BEEN SEEN THIS MORNING OVER WESTERN
UPPER MICHIGAN. THEREFORE...WILL CONTINUE TO SHOW LIKELY POPS IN
THE NORTHWEST WIND AREAS OVER THE WEST IN THE EVENING AND DIMINISH
SLIGHTLY OVERNIGHT WITH THE INCREASING DRY AIR AND BACKING WINDS
ASSOCIATED WITH A WEAK HIGH PRESSURE RIDGE. THE EAST IS A LITTLE
MORE COMPLICATED...SINCE THE ONLY POCKET OF OPEN WATER IS THE AREA
TO THE EAST OF THE KEWEENAW PENINSULA AND SOUTH TO MARQUETTE. WITH
THE NORTHWEST WINDS...THAT WOULD SUPPORT THE HIGHEST POPS/AMOUNTS
OVER ALGER COUNTY AND THINK FARTHER EAST INTO LUCE COUNTY (EVEN THE
EASTERN THIRD OF ALGER COUNTY) WOULD SEE LESS ACCUMULATION AND MORE
SCATTERED SNOW SHOWERS WITH THE AMOUNT OF ICE THE BANDS ORIGINATING
NORTHEAST OF ISLE ROYALE WOULD HAVE TO PASS OVER.
THE WEAK HIGH PRESSURE WILL SLIDE ACROSS THE U.P. LATE TUESDAY
NIGHT AND WEDNESDAY MORNING...AS THE NEXT SHORTWAVE AND LOW
PRESSURE SYSTEM DIVE SOUTHEAST OUT OF WESTERN ONTARIO WEDNESDAY
AFTERNOON AND ACROSS LAKE SUPERIOR AT 998MB ON WEDNESDAY EVENING.
THE BEST SNOW ASSOCIATED WITH THIS LOW AND SHORTWAVE WILL LIKELY BE
NEAR THE SURFACE LOW WITH THE LOWER LEVEL DRY AIR BEING PULL
NORTHEAST ACROSS UPPER MICHIGAN. ANY SYNOPTIC SNOW SHOULD BE LIGHT
AND ONLY CREATE A LIGHT DUSTING...MAINLY NEAR LAKE SUPERIOR. BUT
BEHIND THE LOW...EXPECT ANOTHER OPPORTUNITY FOR LAKE EFFECT SNOW IN
NORTHWEST TO NORTH-NORTHWEST WIND AREAS. THE 925MB WINDS WILL BE
FAIRLY STRONG (35KTS) BEHIND THE FRONT AND WILL LIKELY LIMIT THE
RESIDENCE TIME OVER THE 30-40MI STRETCH OF OPEN WATER. WOULD EXPECT
THIS TO LIMIT SNOWFALL AMOUNTS EVEN THOUGH DELTA-T VALUES ARE
NEARING 30-32 AND INVERSION HEIGHTS ARE BETWEEN 10-14KFT. ALTHOUGH
SNOW AMOUNTS MAY NOT BE TOO SIGNIFICANT...THINK THE PERIOD OF VERY
GUSTY NORTHWEST WINDS ON THE BACK SIDE OF THE LOW (GUSTS NEAR LAKE
SUPERIOR OF 30-40KTS NEAR LAKE SUPERIOR FROM ONTONAGON TO WHITEFISH
POINT) WILL CREATE A SIGNIFICANT CONCERN FOR WIDESPREAD BLOWING AND
DRIFTING SNOW. HAVE TRENDED WINDS UP 5-10KTS FOR THIS PERIOD WITH
THE CONSISTENCY IN THE MODELS ON THIS WINDY IDEA. WILL ALSO ADD A
MENTION OF THE POTENTIAL FOR CONSIDERABLE BLOWING AND DRIFTING SNOW
NEAR LAKE SUPERIOR IN THE HWO THAT WILL DEVELOP WEDNESDAY NIGHT
AND CONTINUE INTO THURSDAY MORNING. ADD FINE FLAKE SNOW FALLING WITH
THE BLOWING SNOW SHOULD EASILY CREATE VISIBILITIES OF 1/2MI OR
LESS IN THE KEWEENAW. THE GUSTY WINDS WILL COMBINE WITH TEMPERATURES
BELOW ZERO ON THURSDAY MORNING TO ALSO CREATE A CONCERN FOR WIND
CHILL HEADLINES FOR A GOOD PORTION OF UPPER MICHIGAN. CURRENT
FORECAST HAS WIND CHILL VALUES OF -25 TO -35 DEGREES AND WITH THE
POTENTIAL FOR BLOWING SNOW IT COULD EVENTUALLY BE TIED TOGETHER WITH
A WINTER WX ADVISORY.
ONCE AGAIN...A HIGH PRESSURE RIDGE (FROM A HIGH MOVING INTO THE
UPPER MISSISSIPPI VALLEY) WILL QUICKLY MOVE OVER UPPER MICHIGAN ON
THURSDAY AFTERNOON INTO THURSDAY NIGHT. THIS SHOULD RAPIDLY
DIMINISH WINDS OVER THE AREA DURING THE AFTERNOON. MODELS CONTINUE
TO SHOW HIGHS ONLY REACHING AROUND 0 DEGREES ON THURSDAY...WHICH
WOULD PUT SEVERAL COLD HIGH TEMPERATURE RECORDS IN JEOPARDY SINCE
MOST ARE IN THE MID SINGLE DIGITS ABOVE ZERO. FOR THE LONG PERIOD OF
RECORD SITES...MOST OF THOSE RECORDS DATE BACK TO THE LATE 1800S AND
EARLY 1900S. WOULD EXPECT SKIES TO CLEAR OUT AWAY FROM ANY LAKE
EFFECT NEAR LAKE SUPERIOR THURSDAY AFTERNOON AND CONTINUE INTO
THURSDAY NIGHT. THINK THIS WILL LEAD TO A VERY COLD NIGHT ACROSS THE
AREA AND WILL CONTINUE TO SHOW LOWS IN THE 10S TO MID 20S BELOW ZERO
(COLDEST INTERIOR COLD SPOTS).
ANOTHER SHORTWAVE WILL ROUND THE EASTERN CANADA UPPER TROUGH ON
FRIDAY AND DIVE SOUTHEAST ACROSS UPPER MICHIGAN FRIDAY NIGHT. THE
COLD AIR ASSOCIATED WITH THIS WAVE WILL LEAD TO ANOTHER DAY OF
HIGHS ABOUT 30 DEGREES BELOW NORMAL ON SATURDAY. LAKE EFFECT
POTENTIAL CONTINUES FRIDAY NIGHT INTO SATURDAY...BUT WORRIED THAT
THE VERY COLD TEMPS AND LIGHT WINDS ON THURSDAY NIGHT INTO FRIDAY
WILL LEAD TO A FAST ICE UP OF THE OPEN AREAS AND CUT OFF LAKE
EFFECT. WILL GO WITH SLIGHT AND LOW CHANCE POPS AT THIS POINT DUE TO
THE UNCERTAINTY. EXTENDED MODELS ARE SHOWING A TREND TOWARDS MORE
ZONAL FLOW AND GRADUALLY WARMING TEMPERATURES SUNDAY AND HEADING
INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1222 PM EST MON FEB 24 2014
AS A WEAK SFC HI PRES RDG/DRIER AIR MOVE IN LATE THIS AFTN/EVNG...
EXPECT IMPROVING CONDITIONS AT ALL 3 TAF SITES...TO MVFR AT IWD/CMX
AND VFR AT SAW. BUT ANOTHER DISTURBANCE WL BRING AN UPTICK IN LK
EFFECT SHSN AND BLSN AT IWD/CMX LATER TNGT...WITH VSBYS FALLING INTO
THE IFR RANGE. DOWNSLOPE WIND COMPONENT INTO SAW SHOULD MAINTAIN VFR
WX THERE. ALTHOUGH SOME DRYING IN THE WAKE OF THIS DISTURBANCE MIGHT
CAUSE AN IMPROVEMENT TO MVFR AT IWD ON TUE...DAYTIME HEATING WL
LIKELY RESULT IN AN MVFR CIG AT SAW WITH THE ARRIVAL OF MORE
UNSTABLE AIR. IFR CONDITIONS ARE LIKELY TO PLAGUE THE EXPOSED CMX
LOCATION THRU 18Z TUE UNDER THIS AXIS OF COLDER AIR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 406 PM EST MON FEB 24 2014
WEST TO NORTHWEST WINDS OF 15-25KTS WILL CONTINUE TONIGHT THROUGH
TUESDAY NIGHT...BUT THEN BACK ON WEDNESDAY MORNING AHEAD OF AN
APPROACHING LOW PRESSURE SYSTEM. A TIGHTENING GRADIENT AHEAD OF
THAT LOW COULD LEAD TO A FEW GALE FORCE GUSTS TO 35KTS AROUND
MID-DAY WEDNESDAY. THEN AS THE LOW DROPS SOUTHEAST ACROSS EASTERN
LAKE SUPERIOR ON WEDNESDAY EVENING...EXPECT A RAPID SWITCH AND
INCREASE IN THE WINDS FROM THE NORTHWEST AND CURRENT THOUGHT IS
THAT MUCH OF THE LAKE WILL SEE GALE FORCE GUSTS TO 35-40KTS. A HIGH
PRESSURE RIDGE WILL QUICKLY MOVE OVER THE AREA THURSDAY
AFTERNOON/NIGHT AND WEAKEN THE WINDS. ANOTHER TROUGH MOVING THROUGH
ON FRIDAY NIGHT WILL INCREASE WINDS BACK TO 15-25KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
357 PM EST MON FEB 24 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 357 PM EST MON FEB 24 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PERSISTENT...COLD
NW FLOW DOMINATING THE GREAT LKS BTWN RDG ALONG THE W COAST AND
CLOSED LO OVER QUEBEC/TROF IN ERN NAMERICA. COMBINATION OF SHRTWV
EMBEDDED IN NW FLOW ALF...DEEPER MSTR SHOWN ON THE 12Z INL RAOB...
H85 TEMPS IN THE -18C TO -21C RANGE AND SOME OPEN WATER ON LK SUP
HAS RESULTED IN SOME GENERALLY LGT LES IN AREAS FAVORED BY THE LLVL
WNW FLOW. OVER THE INTERIOR...SOME DIURNAL CU/SC HAVE DVLPD IN
RATHER MOIST AIRMASS WITH INCRSG SUN ANGLE CAUSING SOME LLVL
DESTABILIZATION. BTWN THE SHRTWV MOVING THRU THE UPR LKS EARLY THIS
AFTN AND ANOTHER STRONGER DISTURBANCE STRETCHING FM NEAR LK WINNIPEG
INTO THE NRN PLAINS/ACCOMPANYING -SN MOVING THRU THE DAKOTAS...
SHRTWV RDG/AXIS OF DRIER MID LVL AIR IS BRINGING GENERALLY MOSUNNY
WX TO MUCH OF MN EXCEPT THE ARROWHEAD. YET ANOTHER SHRTWV IS
DROPPING SWD FM THE NW TERRITORIES OF CANADA INTO NRN SASKATCHEWAN/
MANITOBA.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE LES TRENDS AND TEMPS
ASSOCIATED WITH THE STEADY PARADE OF DISTURBANCES EMBEDDED IN NW
FLOW ALF.
TNGT...WITH APRCH AND PASSAGE OF SHRTWV RDG LATER THIS AFTN AND THIS
EVNG/ACCOMPANYING DEEP LYR QVECTOR DVGC AND SUBSIDENCE...EXPECT
LINGERING LES TO AT LEAST DIMINISH IN INTENSITY/COVERAGE FOR A TIME.
BUT AS SHRTWV NOW MOVING INTO THE NRN PLAINS SHIFTS TO THE SE
TNGT...AREA OF ACCOMPANYING DEEP LYR QVECTOR CNVGC/MORE MSTR AND SFC
COLD FNT ARE FCST TO IMPACT THE AREA MAINLY AFT MIDNGT. ALTHOUGH ALL
MODELS SHOW THE ACCOMPANYING SYNOPTIC SCALE PCPN PASSING TO THE S OF
THE CWA CLOSER TO CORE OF UPR DVGC ON CYC SIDE OF H3 JET MAX...
EXPECT AN INCRS IN LES COVERAGE NEAR LK SUP OVERNGT. TEMPS COULD
FALL OFF QUICKLY THIS EVNG OVER AT LEAST THE INTERIOR NEAR THE WI
BORDER AS AXIS OF DRIER AIR AT LEAST BRIEFLY MOVES OVHD BEFORE
THICKER CLDS ASSOCIATED WITH DISTURBANCE NEAR LK WINNIPEG ARRIVE
LATER.
TUE...WHILE THERE MAY BE SOME MID LVL DRYING/SUBSIDENCE EARLY ON TUE
WITH A PERIOD OF QVECTOR DVGC FOLLOWING THE DEPARTING DISTURBANCE...
SHRTWV NOW DROPPING S INTO SASKATCHEWAN/MANITOBA IS FCST TO BRING A
RETRUN OF MORE DYNAMIC SUPPORT/SOME DEEPER MSTR BY THE AFTN...
ESPECIALLY OVER THE NE HALF OF THE CWA. SO EXPECT INCRSG LES POPS
AGAIN IN THE WNW WIND SN BELTS NEAR THE LK. GIVEN H85 TEMPS FALLING
AOB -25C BY LATE IN THE DAY CAUSING THE NEAR ELIMINATION OF THE DGZ
AS WELL AS CONSIDERABLE ICE COVER OVER LK SUP...EXPECT SN AMOUNTS TO
BE RELATIVELY LIGHT. TUE WL BE ANOTHER UNSEASONABLY COLD DAY. TENDED
TOWARD THE LO END OF GUIDANCE FOR MAX TEMPS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 347 AM EST MON FEB 24 2014
THE 500MB TROUGH WILL LINGER ACROSS E CANADA/E U.S. THROUGH THE
PERIOD. STARTING TUESDAY THE MAIN 500MB LOW SET UP ACROSS HUDSON BAY
WILL EXTEND A LARGE TROUGH FROM SASKATCHEWAN THROUGH THE CENTRAL
PLAINS AND E U.S. EXPECT THE APEX OF THE 500MB TROUGH TO BE ACROSS
THE CWA AT 00Z WEDNESDAY AS THE MAIN LOW SLOWLY SINKS S INTO ONTARIO
AND THE ONTARIO/QUEBEC BORDER THURSDAY. THE CLOSEST THE 500MB LOW
WILL BE TO THE CWA WILL BE WEDNESDAY NIGHT. 500MB TEMPS OF -50C NEAR
THE CENTER OF THE LOW WILL REMAIN TO OUR NE. WHILE SNOW SHOWERS WILL
BE POSSIBLE...MAINLY ALONG LAKE SUPERIOR THROUGH THURSDAY...MUCH OF
THE DISCUSSION BELOW WILL FOCUS ON THE EXTREMELY COLD TEMPERATURES.
COOL NW FLOW WILL BE THE RULE BEHIND THE SFC LOW SWEEPING FROM
NW/CENTRAL ONTARIO AT 18Z WEDNESDAY TO CENTRAL AND NE LAKE SUPERIOR
BY 00Z THURSDAY AND SE QUEBEC EARLY THURSDAY MORNING. THIS WILL
ALLOW THE ARCTIC AIRMASS TO SINK IN AND LINGER THROUGH THE 1ST HALF
OF THE UPCOMING WEEKEND. 850MB TEMPS DURING THIS TIME WILL RANGE
FROM -28 TO -32C. SFC TEMPS WILL GREATLY DEPEND ON CLOUD COVER AND
OPEN WATER ACROSS LAKE SUPERIOR.
COLDEST SFC TEMPS LOOK TO OCCUR FRIDAY MORNING. 2M TEMPS OFF THE
24/00Z GFS SHOW MIN TEMPS OVER N MN AND CENTRAL WI OF -20 TO -30F
/BUT ONLY -5 TO -15F ACROSS UPPER MI/. WITH HIGH PRESSURE NEARLY
OVERHEAD AND WINDS UNDER 5KTS...CONTINUED TO GO ON THE LOW END OF
GUIDANCE. WIND CHILL VALUES WILL NOT BE MUCH LOWER THAN THE ACTUAL
TEMPS THANKS TO THE LIGHT WINDS.
LOW WIND CHILLS ARE INEVITABLE EACH OVERNIGHT/MORNING THROUGH
THURSDAY MORNING. THE LOWEST WIND CHILLS WILL BE LIKELY THURSDAY
MORNING AS UPPER MI RESIDES BETWEEN THE DEEPENED LOW LOVER SE
ONTARIO AND LARGE STRONG HIGH STRETCHING FROM MN TO NW CANADA. A NW
PUFF OF 8-10KTS /STRONGER FROM THE KEWEENAW PENINSULA ALONG THE LAKE
SUPERIOR SHORELINES/ WILL HELP WIND CHILLS FALL TO -20 TO NEARLY
-35F OVER MUCH OF W AND CENTRAL UPPER MI...LOWEST ALONG THE WI
BORDER.
GIVEN ALL THE DISCUSSION ABOUT TEMPERATURES...BELIEVE IT OR
NOT...NORMAL HIGH TEMPS THIS TIME OF YEAR ARE IN THE UPPER 20S AND
LOW 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1222 PM EST MON FEB 24 2014
AS A WEAK SFC HI PRES RDG/DRIER AIR MOVE IN LATE THIS AFTN/EVNG...
EXPECT IMPROVING CONDITIONS AT ALL 3 TAF SITES...TO MVFR AT IWD/CMX
AND VFR AT SAW. BUT ANOTHER DISTURBANCE WL BRING AN UPTICK IN LK
EFFECT SHSN AND BLSN AT IWD/CMX LATER TNGT...WITH VSBYS FALLING INTO
THE IFR RANGE. DOWNSLOPE WIND COMPONENT INTO SAW SHOULD MAINTAIN VFR
WX THERE. ALTHOUGH SOME DRYING IN THE WAKE OF THIS DISTURBANCE MIGHT
CAUSE AN IMPROVEMENT TO MVFR AT IWD ON TUE...DAYTIME HEATING WL
LIKELY RESULT IN AN MVFR CIG AT SAW WITH THE ARRIVAL OF MORE
UNSTABLE AIR. IFR CONDITIONS ARE LIKELY TO PLAGUE THE EXPOSED CMX
LOCATION THRU 18Z TUE UNDER THIS AXIS OF COLDER AIR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 323 AM EST MON FEB 24 2014
NO GALES ARE EXPECTED...BUT SOME HEAVY FREEZING SPRAY IS POSSIBLE IN
ANY OPEN WATERS ON WEDNESDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1203 AM EST MON FEB 24 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 435 PM EST SUN FEB 23 2014
THE UPPER GREAT LAKES REGION IS UNDER THE INFLUENCE OF A UPPER
LOW SPINNING OVER EASTERN ONTARIO AT THIS TIME. THIS UPPER LOW HAS
BEEN ROTATING MID LEVEL MOISTURE SOUTHEAST ACROSS THE REGION TODAY
AS SEEN IN WATER VAPOR IMAGERY AND REPRESENTED ON THE 12Z KINL
SOUNDING. WITH THE OPEN WATER OVER PORTIONS OF WESTERN LAKE
SUPERIOR...MOISTURE FROM THE UPPER LOW...AND RAP ANALYZED 850MB
TEMPS AROUND -22C...HAVE BEEN SEEING LAKE CLOUDS AND LIGHT SNOW
SHOWERS ON WEBCAMS AND SATELLITE OVER NORTHERN ONTONAGON...HOUGHTON
AND KEWEENAW COUNTIES. THERE WAS ONE STRONGER BAND THAT STRETCHED
FROM NORTHERN HOUGHTON COUNTY TO JUST NORTH OF GRAND MARAIS. WHERE
THE RADAR CAN SAMPLE IT IT WAS INDICATING SNOWFALL RATES AROUND
0.5-1 INCH AN HOUR SOUTH EAST OF STANNARD ROCK WHERE IT HAS BEEN
AIDED BY ANOTHER AREA OF OPEN WATER. AS WINDS HAVE BEEN SLOWLY
SHIFTING TO THE NORTHWEST...THIS BAND HAS BEEN SHIFTING SOUTH
THROUGH THE DAY...BUT DID GET A REPORT FROM WHITEFISH POINT OF AN
ESTIMATED 6-8 INCHES OF SNOW. WOULD EXPECT AMOUNTS THAT HIGH IN
NORTHERN LUCE COUNTY WITH THE MOVEMENT BUT THINK AMOUNTS IN THE 1-3
INCH RANGE ARE REASONABLE SINCE THIS MORNING.
AS THE UPPER TROUGH AND SURFACE LOW SHIFT EAST TONIGHT...IT WILL
SWEEP A WEAK SHORTWAVE AND SFC-850MB TROUGH SOUTHEAST ACROSS LAKE
SUPERIOR. THESE TROUGHS WILL ACT TO PROVIDE MORE LOW LEVEL MOISTURE
OVER THE REGION TONIGHT INTO MONDAY MORNING AND TURN THE LOW LEVEL
WINDS TO THE NORTHWEST. 850MB TEMPS OF -23C WILL LEAD TO PLENTY OF
OVER THE LAKE INSTABILITY WHERE THERE IS OPEN WATER (INVERSION
HEIGHTS TO 6-7KFT). THERE IS A LITTLE BIT OF AN UNCERTAINTY ON
THE ICE COVERAGE...BUT BASED OFF YESTERDAY/S MODIS IMAGE AND
LOCATION OF LAKE CLOUDS TODAY...IT APPEARS THERE IS DECENT OPEN
WATER FROM TWO HARBORS MINNESOTA TO ISLE ROYALE...THEN
EAST-NORTHEAST OF ISLE ROYALE TO NORTHERN LAKE SUPERIOR AND ALSO TO
THE EAST OF THE KEWEENAW AND TOWARDS MARQUETTE. WHERE ICE CAN BE
MADE OUT...THERE HAS BEEN DECENT MOVEMENT WITH THE WEST-NORTHWEST
WINDS OF 20-30KTS. WITH WEAKENING WINDS INCREASING THE RESIDENCE
TIME OVER THE 20-30MI AREA OF OPEN WATER OVER THE WEST
TONIGHT...THINK THAT WILL BE ENOUGH FOR LIGHT AND OCCASIONALLY
MODERATE LAKE EFFECT SNOWS TO OCCUR FROM CALUMET SOUTHWEST TO
IRONWOOD AND WILL CONTINUE TO SHOW LIKELY AND LOW DEFINITE POPS
FOR THOSE AREAS TONIGHT. NORTH OF CALUMET IS A LITTLE UNCERTAIN ONCE
WINDS TURN TO THE NORTHWEST DUE TO MORE ICE BETWEEN ISLE ROYALE AND
THUNDER BAY AND SMALLER GAPS IN THE FIRST 10-15MI SOUTHEAST FROM
ISLE ROYALE. THEREFORE...WILL HAVE THE POPS LOWER INTO THE LOW END
LIKELY CATEGORY ONCE THE WINDS TURN TO THE NORTHWEST.
OVERALL...SNOWFALL AMOUNTS SHOULD BE LIGHT AND IN THE 1-4 INCH
RANGE. GUSTY THIS EVENING (TO 35MPH)...BUT WITH THE LOW WEAKENING
AND SHIFTING EAST TONIGHT...SHOULD SEE A GRADUAL DIMINISHING TREND
TO THE WINDS. THIS WILL LEADING TO IMPROVING VISIBILITIES FROM THE
BLOWING SNOW OVER THE KEWEENAW PENINSULA. SINCE WE ARE STILL
GETTING REPORTS FROM OBS/WEBCAMS/SPOTTERS OF VISIBILITIES BELOW
1/2MI AT TIMES...DECIDED TO EXTEND THE ADVISORY UNTIL MIDNIGHT.
THIS WILL COVER THE EVENING TRAVEL PERIOD BEFORE THE WINDS DIMINISH
OVERNIGHT.
FARTHER EAST...THE MAIN AREA OF CONCERN WILL BE OVER NORTHERN
LUCE AND THEN TRANSITIONING INTO ALGER COUNTY DUE TO THE FAVORABLE
FETCH ACROSS THE OPEN WATER THAT LIKELY COVERS A DECENT PORTION OF
LSZ265. WITH NORTHWEST WINDS AND PROBABLY SOME LAND BREEZE
INFLUENCE...WOULD THINK THERE WOULD BE SOME ENHANCED LAKE EFFECT
BAND AFFECTING THE COUNTY AND GRADUALLY TRANSITIONED THE BAND
SOUTHWEST THIS EVENING TO AROUND AND JUST EAST OF MUNISING AREA
OVERNIGHT. WITH A POTENTIAL FETCH OF 80MI AND SOME UPSTREAM
MOISTENING OVER THE WESTERN LAKE...WOULDN/T BE SURPRISED IF THERE
ARE SOME LOCALIZED 4 INCH AMOUNTS ESPECIALLY IF THE BAND STALLS IN
AN AREA FOR A FEW HOURS. EAST OF THERE...THE AMOUNT OF ICE COVERAGE
WILL LIKELY LIMIT AMOUNTS AND ONLY HAVE VALUES IN THE 1 TO MAYBE 2
INCH RANGE.
WILL START TO SEE THE AFFECT OF RIDGING UPSTREAM THROUGH THE DAY
TOMORROW AS THE UPPER LOW SHIFTS EAST. THIS WILL LEAD TO INCREASING
850MB TEMPERATURES (ALONG WITH SOME DRYING AND BACKING WINDS) FROM
WEST TO EAST...ESPECIALLY IN THE AFTERNOON. THUS...WILL FOLLOW THAT
TREND FOR POPS AND SNOWFALL AMOUNTS THROUGH THE DAY. HIGHS TOMORROW
WILL BE IN THE LOW-MID TEENS OVER MUCH OF THE AREA. THIS LOOKS TO
BE THE WARMEST HIGHS FOR THE REST OF THE WORK WEEK.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 435 PM EST SUN FEB 23 2014
THE CWA WILL BE DOMINATED BY LOW WIND CHILLS...AND LIGHT TO MODERATE
LES FOR AREAS DOWNWIND OF W TO NW FLOW OVER GAPS IN THE CONSIDERABLE
LAKE ICE COVER.
MON NIGHT...THE STRONGEST 850-500 MB QVECTOR CONV AND
LOWER LEVEL WAA/ISENTROPIC LIFT ASSOCIATED WITH THE FIRST IN A SERIES
OF SHORTWAVE TROUGHS IS EXPECTED TO REMAIN WELL TO THE SOUTH THROUGH
IA INTO SRN WI AND NRN IL. WRLY FLOW LES BANDS WILL SHIFT SLIGHTLY AS
WINDS VEER TO WNW BEHIND A WEAK SFC TROUGH. WITH CONTINUED
UNCERTAINTY ON THE EXTENT OF OPEN WATER AND INVERSION HEIGHTS ONLY
AROUND 5K FT...MENTIONED LIKELY POPS BUT WITH FCST SNOWFALL AMOUNTS
ONLY OF AROUND AN INCH OR TWO.
TUE INTO TUE NIGHT...THE MODELS SUGGEST ANOTHER SHRTWV WITH AN ARCTIC
FRONT BRINGING IN EVEN COLDER AIR WILL MOVE THROUGH BY LATE TUE INTO
TUE NIGHT. WINDS WILL VEER TO THE NW PUSHING THE LIGHT LES OVER A
GRATER PORTION OF THE ERN CWA. WITH MIN TEMPS DROPPING INTO THE -4F
TO -14F RANGE...WIND CHILLS SHOULD ALSO FALL INTO THE -20 TO -30
RANGE.
WED-FRI...A STRONGER SHRTWV WILL MOVE THROUGH THE NRN LAKES AS THE
POLAR TROUGH MOVES INTO NRN ONTARIO. WINDS ARE EXPECTED TO VEER TO
THE NW TO NNW BEHIND THIS FEATURE AS 850 MB TEMPS DROP TO AROUND
-31C THU. WITH THE STRONGER NW WINDS...THE LOWEST WIND CHILLS ARE
EXPECTED THU MORNING INTO THE -25 TO -35 RANGE EVEN THOUGH THERE MAY
SOME MODIFICATION OVER THE MOSTLY FROZEN LAKE. WITH LIGHTER WINDS
AND FEW CLOUDS BY FRI AS THE ARCTIC HIGH SETTLES OVER THE
AREA...TEMPS SHOULD DROP AT LEAST INTO THE -15 TO -25 RANGE OVER
MUCH OF THE CWA...WITH SOME -30S EVEN POSSIBLE FOR TRADITIONAL COLD
SPOTS.
SAT-SUN...THERE IS GREATER UNCERTAINTY WITH ANY INDIVIDUAL SHRTWVS
BUT WITH THE POLAR TROUGH LINGERING NEAR JAMES BAY...ANOTHER BOUT OF
LOWER 850 MB TEMPS AND HIGHER WINDS MAY MOVE IN BY SAT WITH
DIMINISHING WINDS AND CONTINUED COLD ON SUN WITH THE ARCTIC RIDGE
DOMINATING THE NRN LAKES. BY THE WEEKEND...THE ICE COVER IS LIKELY
TO SOLIDIFY...REDUCING LES CHANCES/AMOUNTS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1203 AM EST MON FEB 24 2014
WITH LIGHTER NW WINDS AND LESS BLSN...EXPECT MVFR CONDITIONS TO
PREVAIL THRU THE FCST PERIOD AT KCMX. HOWEVER...WITH OCNL LAKE
EFFECT -SHSN...THERE WILL LIKELY BE SOME PERIODS OF IFR CONDITIONS
AS WELL. DISTURBANCE CROSSING THE AREA THIS EVENING COULD BRING MORE
SUSTAINED IFR VIS.
AT KIWD...LAKE EFFECT -SHSN AND IFR CONDITIONS HAVE DEVELOPED AS
EXPECTED DUE TO WINDS VEERING MORE TO THE NW. IFR CONDITIONS SHOULD
PREVAIL OVERNIGHT INTO THE EARLY MORNING. THEREAFTER...THERE SHOULD
BE SOME IMPROVEMENT BACK TO MVFR BY LATE MORNING AS DEEPER MOISTURE
EXITS. CONDITIONS MAY IMPROVE TO VFR AT TIMES DURING THE
AFTN/EVENING.
AT KSAW...DOWNSLOPE NATURE OF THE W TO NW FLOW HAS RESULTED IN
CONDITIONS REMAINING VFR. HOWEVER...WITH INCREASE IN LOW-LEVEL
MOISTURE...HIGH MVFR CIGS SHOULD STILL DEVELOP OVERNIGHT...THEN LIFT
TO VFR THIS AFTN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 PM EST SUN FEB 23 2014
THE WEAKENING LOW NEAR HUDSON BAY WILL COMBINE WITH A HIGH PRESSURE
RIDGE MOVING THROUGH THE NORTHERN PLAINS AND MID MISSISSIPPI VALLEY
TO LEAD TO GRADUALLY DECREASING WEST TO NORTHWEST WINDS OVER LAKE
SUPERIOR TONIGHT THROUGH MONDAY NIGHT. HAVE BEEN SEEING THE GALES
PERSISTING OVER THE EASTERN PART OF LAKE SUPERIOR ON THE STANNARD
ROCK AND GRANITE ISLAND OBS THIS AFTERNOON...BUT WITH UPSTREAM OBS
GENERALLY IN THE 30KT RANGE...WOULD EXPECT THE EASTERN SITES TO
COME DOWN SHORTLY. THUS...WILL ALLOW THE GALE WARNING OVER THE
EASTERN LAKE TO EXPIRE AT 00Z AND HAVE ALREADY CANCELLED THE
WESTERN LAKE. EVEN WITH THIS DIMINISHMENT...THERE WILL LIKELY BE
ENOUGH OF A GRADIENT TO KEEP WINDS IN THE 15 TO 30KT RANGE FOR MUCH
OF THE FORECAST PERIOD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
515 PM CST TUE FEB 25 2014
.UPDATE...QUICK UPDATE HERE TO TOUCH ON SOME RECENT TRENDS FOR
THIS EVENING/OVERNIGHT. THE MAIN CONCERN WILL BE FOR SOME DECENT
RAINFALL AMOUNTS ACROSS THE SOUTHERN PARTS OF THE CWA. LATEST HI-RES
NCEP MODELS...LOCAL WRF AND HRRR INDICATE LOCATIONS ALONG AND SOUTH
OF THE HWY 84 CORRIDOR COULD SEE 1-2 INCHES. IF MULTIPLE STORMS
OCCUR (WHICH IS A POSSIBILITY) THEN SOME LOCALIZED AREAS COULD SEE
HIGHER TOTALS WHICH COULD CAUSE SOME FLOODING ISSUES. WE WILL
CONTINUE TO MONITOR THIS AND ADD HAZARDS TO THE HWO IF CONFIDENCE
INCREASES IN THE FLOODING POTENTIAL. ADDITIONALLY...DURING THE
INITIAL ONSET OF CONVECTION ACROSS THE SW...THERE LOOKS TO EXIST
JUST ENOUGH ELEVATED INSTABILITY (FROM STEEP LAPSE RATES) TO SUPPORT
SOME SMALL HAIL OF PENNY SIZED OR LESS. THIS WOULD ONLY BE POSSIBLE
ACROSS THE FAR SW ZONES AND BETWEEN 6-8 PM. /CME/
&&
.PREV DISCUSSION... /ISSUED 353 PM CST TUE FEB 25 2014/
SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...RAIN WILL BE
SPREADING ACROSS THE REGION TONIGHT AS A SHORTWAVE AND ASSOCIATED
COLD FRONT MOVES THROUGH THE REGION. LATEST MODELS INDICATE THAT
SOME SLEET COULD MIX IN LATER TONIGHT ALONG AND NORTH OF THE HIGHWAY
82 CORRIDOR AS COLDER AIR MOVES IN BEHIND THE FRONT. TEMPERATURES
SHOULD REMAIN ABOVE FREEZING SO NO WINTRY MIX ACCUMULATION IS
EXPECTED. GUSTY NORTH WINDS WILL DEVELOP TONIGHT INTO WEDNESDAY
MORNING BEHIND THE FRONT WHICH COULD RESULT IN WIND CHILLS FALLING
INTO THE LOWER 20S AT LOCATIONS ALONG THE HIGHWAY 82 CORRIDOR. RAIN
CHANCES WILL GRADUALLY BE ENDING FROM WEST TO EAST WEDNESDAY AS
DRIER AIR SURGES INTO THE REGION AND STRONG HIGH PRESSURE BUILDS
SOUTH. SKIES WILL GRADUALLY CLEAR FROM THE NORTH WEDNESDAY. HIGHS
WEDNESDAY AFTERNOON WILL NOT CLIMB OUT OF THE 30S AT SOME LOCATIONS
IN THE NORTH. THE SHORTWAVE AXIS WILL SHIFT EAST OF OUR CWA BY
WEDNESDAY NIGHT BUT SURFACE RIDGING WILL SHIFT OVER OUR CWA. THIS
WILL SET UP THE COLDEST NIGHT OF THE FORECAST PERIOD WITH MUCH OF
THE AREA BOTTOMING OUT IN THE LOWER 20S AND THE REMAINDER OF THE
AREA IN THE MID TO UPPER 20S. A BROAD UPPER TROUGH WILL KEEP THE
ARKLAMISS REGION DRY WITH BELOW NORMAL TEMPERATURES THROUGH THURSDAY
NIGHT. /27/22/
LONG TERM...FRIDAY THROUGH TUESDAY...AS WE GO INTO FRIDAY AND INTO
THE WEEKEND...THE PATTERN WILL BECOME MORE ZONAL AS MILDER PACIFIC
AIR PUSHES TEMPS BACK TO NEAR NORMAL. COLD AIR ADVECTION WILL HOLD
TEMPS INTO THE 50S ON THURSDAY AS A REINFORCING FRONT PUSHES THROUGH
THE REGION. THE ASSOCIATED SURFACE HIGH WILL SHIFT EAST OF OUR CWA
FRIDAY AFTERNOON. DRY WEATHER WILL CONTINUE THURSDAY INTO FRIDAY BUT
A WEAK DISTURBANCE WILL DROP OVER THE SOUTHERN PLAINS THURSDAY AND
HELP DEVELOP A WEAK SURFACE LOW. WARM AIR ADVECTION AHEAD OF THIS
SYSTEM WILL BRING SOME LIGHT RAIN BACK INTO ARKLAMISS ON FRIDAY NIGHT
AS A WEAK WARM FRONT PUSHES INTO THE REGION. THE GFS...EURO AND
NAVGEM WERE PRETTY LIGHT WITH THE RAINFALL FOR FRIDAY NIGHT. THE
SYSTEM WILL EXIT EAST ON SATURDAY AS FLAT UPPER RIDGING PUSHES ACROSS
THE REGION. HIGHS WILL RISE INTO THE 50S NORTH TO AROUND 70 SOUTH FOR
SATURDAY AS WELL AS 60S AND 70S ON SUNDAY. LOWS WILL BE IN THE 40S.
AS WE GO INTO SUNDAY NIGHT ANOTHER WAVE WILL APPROACH FROM THE WEST.
A STRONGER WARM FRONT WILL PUSH INTO THE REGION SUNDAY NIGHT INTO
MONDAY. INSTABILITY WILL BUILD ACROSS THE REGION FOR SUNDAY NIGHT
WITH A CHANCE OF THUNDERSTORMS. AS WE GO INTO MONDAY MOISTURE
CONVERGENCE WILL INCREASE...AS WELL AS SOME JET DYNAMICS AND ASCENT
ACROSS THE REGION. THE CIPS MODEL SHOWS SOME LIMITED SEVERE POTENTIAL
WITH THIS SYSTEM...AS A STRONG UPPER TROUGH PUSHES THROUGH THE PLAINS
FOR EARLY NEXT WEEK. ALSO PWATS WILL BE AROUND 1.7 WHICH IS THE MAX
PERCENTILE FOR THIS TIME OF YEAR FOR SOME LOCALLY HEAVY RAINFALL
POTENTIAL. THERE WERE SOME MODEL DISCREPANCIES WITH THIS SYSTEM THE
GFS...NAVGEM AND GFS ENSEMBLES BRING THE COLD FRONT THROUGH MONDAY
NIGHT INTO EARLY TUESDAY...WHILE THE EURO BROUGHT THE FRONT THROUGH
ON SUNDAY NIGHT. BEING THIS FAR OUT WILL GO WITH THE SLOWER GFS
SOLUTION AND WILL WATCH THE STRONG STORM POTENTIAL...BUT NOT MENTION
IT IN THE HWO BEING A WEEK AWAY.
AS FAR AS TEMPS ARE CONCERN MADE SOME SLIGHT ADJUSTMENTS TO MEX
GUIDANCE TOWARD GMOS...HPC AND SOME MEN ENSEMBLES DURING THE
PERIOD. AS FAR AS POPS ARE CONCERN WENT WITH A BLEND OF MEX AND MEN
ENSEMBLES. /17/
&&
.AVIATION...
A COLD FRONT EXTENDS ACROSS THE CENTRAL PORTIONS OF THE
STATE THIS AFTERNOON AND IS SLOWLY MOVING SOUTH. A FEW LIGHT
RAINSHOWERS WERE NOTED ALONG THE FRONT. MOSTLY VFR CEILINGS ARE
OCCURRING NORTH OF THE BOUNDARY WHILE A MIX OF MVFR/VFR CEILINGS ARE
OCCURRING SOUTH. RAIN WILL BE ON THE INCREASE THIS EVENING INTO THE
OVERNIGHT HOURS AND EXPECT A RETURN TO MVFR AND IFR CONDITIONS LATER
TONIGHT OVER MOST SITES. LIGHT SLEET MAY MIX WITH THE RAIN 09Z-13Z
WED AT GLH-GWO-GTR. CONDITIONS WILL GRADUALLY IMPROVE FROM THE NORTH
WED.
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 36 42 24 55 / 100 45 10 4
MERIDIAN 39 44 23 56 / 91 53 9 4
VICKSBURG 37 41 24 55 / 100 34 10 4
HATTIESBURG 45 46 30 57 / 100 81 14 5
NATCHEZ 38 41 26 54 / 100 81 13 8
GREENVILLE 33 40 24 51 / 90 21 6 2
GREENWOOD 34 40 21 54 / 86 21 6 3
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
CME/27/17
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1153 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST MON FEB 24 2014
1038 MB ARCTIC HIGH PRESSURE ACROSS SRN ALBERTA AND SRN
SASKATCHEWAN WILL MOVE INTO SOUTH DAKOTA BY 12Z TUESDAY MORNING.
AN ARCTIC FRONT ACROSS NRN MT IS EXPECTED TO MOVE INTO THE FCST
AREA BY LATE AFTN AND BE THROUGH THE FCST AREA AND ACROSS KS BY
TUESDAY MORNING. LOWS IN THE SINGLE DIGITS ARE EXPECTED TONIGHT
WITH WIND CHILL READINGS AROUND 10 BELOW TO PERHAPS 15 BELOW ZERO
ACROSS NORTHERN NEB.
THE MODEL CONSENSUS SUGGESTS A PERIOD OF LIGHT SNOW
DEVELOPING...MAINLY ACROSS WRN NEBRASKA...AS THE FRONT MOVES
THROUGH. SNOWFALL AMOUNTS SHOULD BE LESS THAN AN INCH AND MAINLY
A DUSTING.
THERE IS QUITE A VARIETY OF MAX TEMPERATURE FORECASTS TO CHOOSE
FROM TODAY. THE FORECAST FOLLOWS A BLEND OF NAM...GEM REG...ECM
AND MET PLUS BIAS CORRECTION FOR HIGHS IN THE UPPER 20S NORTH TO
UPPER 30S SOUTH. THE NAM IS ACTUALLY FORECASTING MID 40S AT NORTH
PLATTE WHILE THE RAP SHOWS UPPER 20S AND THE ECM MID 30S. THIS IS
A FUNCTION OF THE SKY COVER INDICATED IN THE MODELS AND SOME
SOLNS SHOW A PERIOD OF CLEARING AHEAD OF THE ARCTIC FRONT. THE
MODEL CONSENSUS SUGGESTS CLEARING ACROSS WRN/SWRN
NEB...KAIA-KOGA-KIML AS A RESULT OF SOME SOUTHWEST WINDS
DEVELOPING. EAST OF THAT AREA IT LOOKS LIKE ARCTIC DRAPE SHOULD
CONTINUE WITH SOUTH WINDS.
THE LIGHT TO MODERATE SNOW ON RADAR EARLY THIS MORNING ACROSS
NCNTL NEB IS MOVING RAPIDLY EAST AND SHOULD BE REPLACED BY A
SECOND AREA OF SNOW LATER THIS MORNING A BIT FARTHER NORTH AND
EAST. THIS SNOW IS CURRENTLY SHOWING ON THE KUNR RADAR ACROSS WRN
SD. THE MODELS GENERATE A THIRD AREA OF SNOW THIS AFTERNOON BUT
THIS SHOULD PASS MOSTLY NORTH AND EAST OF THE FORECAST AREA. THIS
AREA OF SNOW IS CURRENTLY ACROSS SERN MT.
BEST SNOWFALL IS EXPECTED ACROSS BOYD COUNTY WITH QPF RANGES FROM
LESS THAN 0.10 INCHES IN THE UKMET...GEF AND GFS TO 0.30 INCHES
IN THE NMM WEST. THIS IS A WIDE RANGE AND THE CONSENSUS IS AROUND
0.15 INCHES. A 15 TO 20 TO 1 SNOW RATIO WAS USED BASED ON THE
COBB METHODOLOGY. OBSERVED SNOWFALL SUNDAY AFTN AND SUNDAY NIGHT
WAS IN THIS RANGE. THE NAM CONTINUES TO ADVERTISE POCKETS OF
STRONG FRONTOGENESIS WHICH COULD LEAD TO BANDED SNOW DEVELOPMENT.
THIS HAS BEEN THE OPERATIVE MODE IN MANY INSTANCES OVER THE PAST
36 HOURS HOWEVER THE NAM...ARF AND NMM MODELS HAVE SHOWN POOR
SKILL FORECASTING THE LOCATION OF THESE BANDS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM CST MON FEB 24 2014
TEMPS FOR THE END OF FEBRUARY AND INTO MARCH WILL BE DOMINATED BY
COLD ARCTIC AIR WITH WELL BELOW NORMAL READINGS. WEDNESDAY LOOKS
TO BE THE ONLY DAY WE MAY BE WITHIN 10 DEGREES OF NORMAL FOR
HIGHS INTO THE NEXT WEEKEND. ALSO WILL SEE AN ACTIVE PERIOD WITH
SEVERAL CHANCES FOR SNOW THROUGHOUT THE WEEK AND INTO THE
WEEKEND.
TUESDAY WILL SEE ANOTHER DISTURBANCE DRIFTING ACROSS THE SW
PORTIONS OF THE CWA. BATTLE WILL BE BETWEEN RADIATION OF A HIGHER
LATE FEBRUARY SUN ANGLE AND SNOWFALL RATES...ON TOP OF A SNOW
PACK. PLOWED ROADS TODAY FOR THE MOST PART BECAME WET AND IN SOME
AREAS EVEN PARTIALLY DRIED...DESPITE CLOUDY SKIES. THINK CLOUDS
WILL BE THICKER LIMITING SOLAR IMPACT...HOWEVER MODELS ARE ONLY
PRODUCING LIGHT SNOW. DAYTIME SNOW OF A HALF INCH TO 1.5 INCHES
FOR THE MOST PART WITH A 15 TO 1 RATIO...HIGHEST ACROSS THE
SOUTHEASTERN PAN HANDLE AND SW NEB.
BY TUESDAY NIGHT ARCTIC HIGH PRESSURE WILL BE DRIFTING OVERHEAD.
CENTER CROSSES OVER THE CWA BETWEEN 04Z AND 09Z. BY 12Z THE HIGH
WILL BE TO THE SE WITH SOUTHWESTERLY WINDS TO BE ON THE
INCREASING...ALONG WITH WAA. LOWS INITIALLY EXPECTED WITH THE
CENTER OF THE HIGH OVERHEAD...EARLY IN THE NIGHT...HOWEVER WITH
THE EXPECTED SNOW PACK...DECOUPLING WILL KEEP WINDS FROM MIXING TO
THE GROUND UNTIL SUNRISE OR LATER. THIS MAY ALLOW A COUPLE OF
DEGREES FURTHER OF A DROP AFTER CENTER PASSES. EITHER
WAY...EXPECT LOWS TO FALL TO A FEW DEGREES ON EITHER SIDE OF ZERO.
WITH THE WAA FOR WED...HIGHS WILL REBOUND ABOVE FREEZING. WARMEST
GUIDANCE IS INTO THE 40S...HOWEVER THINK SNOW PACK WILL HOLD HIGHS
IN THE 30S.
NEXT COLD FRONT ARRIVES FOR THURSDAY WITH TEMPS TO TAKE A
DOWNWARD TREND. A COUPLE OF REINFORCING COLD FRONT WILL CONTINUE
TO TAKE TEMPS LOWER INTO THE WEEKEND. THIS WILL BE COUPLED WITH
SEVERAL DISTURBANCE TO RIDE ACROSS THE HIGH PLAINS WITH SEVERAL
CHANCES FOR SNOW. SNOW IS NOT EXPECTED TO BE CONSTANT...HOWEVER
CHANCES FOR AT LEAST LIGHT SNOW IN ANY 12 HOURS PERIOD WILL
RESULT IN MANY PERIODS WITH SNOW IN THE FORECAST.
NORMAL HIGHS THIS TIME OF YEAR SHOULD BE INTO THE 40S WITH LOWS
IN THE TEENS. MODELS ARE IN GOOD AGREEMENT WITH HIGHS ONLY IN THE
10S AND 20S FROM FRIDAY THROUGH THE WEEKEND AS THE COLD AIR
BLANKETS MUCH OF THE CONUS. COLDEST GUIDANCE IS THE EC WITH MANY
LOCATIONS NOT WARMING ABOVE SINGLE DIGITS FOR THE WEEKEND. THIS
IS NEARLY 40 DEGREES BELOW NORMAL. SUN ANGLE CONTINUES TO
INCREASE...AND RECORD LOW MAXES ARE IN THE SINGLE DIGITS...SO DO
NOT WANT TO GO WITH THE RECORD COLD FROM THE EC YET...THUS
FORECAST IS FAVORING A SLIGHTLY WARMER GFS AT THIS TIME. HOWEVER
WILL CONTINUE TO KEEP AN EYE ON THIS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1153 AM CST MON FEB 24 2014
THE MAIN CONCERN OVER THE NEXT 24 HOURS IS THE PASSAGE OF A COLD
FRONT THROUGH WESTERN NEBRASKA. WINDS WILL RAPIDLY SWITCH TO
NORTHWEST AND INCREASE IN SPEED LATE THIS AFTERNOON. SNOW SHOWERS
MAY ACCOMPANY THE FRONT...ESPECIALLY ACROSS NORTHERN NEBRASKA
INCLUDING THE KVTN TERMINAL. CEILINGS SHOULD RAISE TO VFR OVERNIGHT
BEHIND THE FRONT AS WINDS STAY STRONG ENOUGH TO PREVENT FOG FORMATION.
STRATUS WILL WORK INTO SOUTHWEST NEBRASKA AGAIN TUESDAY
MORNING...BUT THE PRECIPITATION SHOULD HOLD OFF UNTIL AFTER 25/18Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...SNIVELY/TAYLOR
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
532 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST MON FEB 24 2014
1038 MB ARCTIC HIGH PRESSURE ACROSS SRN ALBERTA AND SRN
SASKATCHEWAN WILL MOVE INTO SOUTH DAKOTA BY 12Z TUESDAY MORNING.
AN ARCTIC FRONT ACROSS NRN MT IS EXPECTED TO MOVE INTO THE FCST
AREA BY LATE AFTN AND BE THROUGH THE FCST AREA AND ACROSS KS BY
TUESDAY MORNING. LOWS IN THE SINGLE DIGITS ARE EXPECTED TONIGHT
WITH WIND CHILL READINGS AROUND 10 BELOW TO PERHAPS 15 BELOW ZERO
ACROSS NORTHERN NEB.
THE MODEL CONSENSUS SUGGESTS A PERIOD OF LIGHT SNOW
DEVELOPING...MAINLY ACROSS WRN NEBRASKA...AS THE FRONT MOVES
THROUGH. SNOWFALL AMOUNTS SHOULD BE LESS THAN AN INCH AND MAINLY
A DUSTING.
THERE IS QUITE A VARIETY OF MAX TEMPERATURE FORECASTS TO CHOOSE
FROM TODAY. THE FORECAST FOLLOWS A BLEND OF NAM...GEM REG...ECM
AND MET PLUS BIAS CORRECTION FOR HIGHS IN THE UPPER 20S NORTH TO
UPPER 30S SOUTH. THE NAM IS ACTUALLY FORECASTING MID 40S AT NORTH
PLATTE WHILE THE RAP SHOWS UPPER 20S AND THE ECM MID 30S. THIS IS
A FUNCTION OF THE SKY COVER INDICATED IN THE MODELS AND SOME
SOLNS SHOW A PERIOD OF CLEARING AHEAD OF THE ARCTIC FRONT. THE
MODEL CONSENSUS SUGGESTS CLEARING ACROSS WRN/SWRN
NEB...KAIA-KOGA-KIML AS A RESULT OF SOME SOUTHWEST WINDS
DEVELOPING. EAST OF THAT AREA IT LOOKS LIKE ARCTIC DRAPE SHOULD
CONTINUE WITH SOUTH WINDS.
THE LIGHT TO MODERATE SNOW ON RADAR EARLY THIS MORNING ACROSS
NCNTL NEB IS MOVING RAPIDLY EAST AND SHOULD BE REPLACED BY A
SECOND AREA OF SNOW LATER THIS MORNING A BIT FARTHER NORTH AND
EAST. THIS SNOW IS CURRENTLY SHOWING ON THE KUNR RADAR ACROSS WRN
SD. THE MODELS GENERATE A THIRD AREA OF SNOW THIS AFTERNOON BUT
THIS SHOULD PASS MOSTLY NORTH AND EAST OF THE FORECAST AREA. THIS
AREA OF SNOW IS CURRENTLY ACROSS SERN MT.
BEST SNOWFALL IS EXPECTED ACROSS BOYD COUNTY WITH QPF RANGES FROM
LESS THAN 0.10 INCHES IN THE UKMET...GEF AND GFS TO 0.30 INCHES
IN THE NMM WEST. THIS IS A WIDE RANGE AND THE CONSENSUS IS AROUND
0.15 INCHES. A 15 TO 20 TO 1 SNOW RATIO WAS USED BASED ON THE
COBB METHODOLOGY. OBSERVED SNOWFALL SUNDAY AFTN AND SUNDAY NIGHT
WAS IN THIS RANGE. THE NAM CONTINUES TO ADVERTISE POCKETS OF
STRONG FRONTOGENESIS WHICH COULD LEAD TO BANDED SNOW DEVELOPMENT.
THIS HAS BEEN THE OPERATIVE MODE IN MANY INSTANCES OVER THE PAST
36 HOURS HOWEVER THE NAM...ARF AND NMM MODELS HAVE SHOWN POOR
SKILL FORECASTING THE LOCATION OF THESE BANDS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM CST MON FEB 24 2014
TEMPS FOR THE END OF FEBRUARY AND INTO MARCH WILL BE DOMINATED BY
COLD ARCTIC AIR WITH WELL BELOW NORMAL READINGS. WEDNESDAY LOOKS
TO BE THE ONLY DAY WE MAY BE WITHIN 10 DEGREES OF NORMAL FOR
HIGHS INTO THE NEXT WEEKEND. ALSO WILL SEE AN ACTIVE PERIOD WITH
SEVERAL CHANCES FOR SNOW THROUGHOUT THE WEEK AND INTO THE
WEEKEND.
TUESDAY WILL SEE ANOTHER DISTURBANCE DRIFTING ACROSS THE SW
PORTIONS OF THE CWA. BATTLE WILL BE BETWEEN RADIATION OF A HIGHER
LATE FEBRUARY SUN ANGLE AND SNOWFALL RATES...ON TOP OF A SNOW
PACK. PLOWED ROADS TODAY FOR THE MOST PART BECAME WET AND IN SOME
AREAS EVEN PARTIALLY DRIED...DESPITE CLOUDY SKIES. THINK CLOUDS
WILL BE THICKER LIMITING SOLAR IMPACT...HOWEVER MODELS ARE ONLY
PRODUCING LIGHT SNOW. DAYTIME SNOW OF A HALF INCH TO 1.5 INCHES
FOR THE MOST PART WITH A 15 TO 1 RATIO...HIGHEST ACROSS THE
SOUTHEASTERN PAN HANDLE AND SW NEB.
BY TUESDAY NIGHT ARCTIC HIGH PRESSURE WILL BE DRIFTING OVERHEAD.
CENTER CROSSES OVER THE CWA BETWEEN 04Z AND 09Z. BY 12Z THE HIGH
WILL BE TO THE SE WITH SOUTHWESTERLY WINDS TO BE ON THE
INCREASING...ALONG WITH WAA. LOWS INITIALLY EXPECTED WITH THE
CENTER OF THE HIGH OVERHEAD...EARLY IN THE NIGHT...HOWEVER WITH
THE EXPECTED SNOW PACK...DECOUPLING WILL KEEP WINDS FROM MIXING TO
THE GROUND UNTIL SUNRISE OR LATER. THIS MAY ALLOW A COUPLE OF
DEGREES FURTHER OF A DROP AFTER CENTER PASSES. EITHER
WAY...EXPECT LOWS TO FALL TO A FEW DEGREES ON EITHER SIDE OF ZERO.
WITH THE WAA FOR WED...HIGHS WILL REBOUND ABOVE FREEZING. WARMEST
GUIDANCE IS INTO THE 40S...HOWEVER THINK SNOW PACK WILL HOLD HIGHS
IN THE 30S.
NEXT COLD FRONT ARRIVES FOR THURSDAY WITH TEMPS TO TAKE A
DOWNWARD TREND. A COUPLE OF REINFORCING COLD FRONT WILL CONTINUE
TO TAKE TEMPS LOWER INTO THE WEEKEND. THIS WILL BE COUPLED WITH
SEVERAL DISTURBANCE TO RIDE ACROSS THE HIGH PLAINS WITH SEVERAL
CHANCES FOR SNOW. SNOW IS NOT EXPECTED TO BE CONSTANT...HOWEVER
CHANCES FOR AT LEAST LIGHT SNOW IN ANY 12 HOURS PERIOD WILL
RESULT IN MANY PERIODS WITH SNOW IN THE FORECAST.
NORMAL HIGHS THIS TIME OF YEAR SHOULD BE INTO THE 40S WITH LOWS
IN THE TEENS. MODELS ARE IN GOOD AGREEMENT WITH HIGHS ONLY IN THE
10S AND 20S FROM FRIDAY THROUGH THE WEEKEND AS THE COLD AIR
BLANKETS MUCH OF THE CONUS. COLDEST GUIDANCE IS THE EC WITH MANY
LOCATIONS NOT WARMING ABOVE SINGLE DIGITS FOR THE WEEKEND. THIS
IS NEARLY 40 DEGREES BELOW NORMAL. SUN ANGLE CONTINUES TO
INCREASE...AND RECORD LOW MAXES ARE IN THE SINGLE DIGITS...SO DO
NOT WANT TO GO WITH THE RECORD COLD FROM THE EC YET...THUS
FORECAST IS FAVORING A SLIGHTLY WARMER GFS AT THIS TIME. HOWEVER
WILL CONTINUE TO KEEP AN EYE ON THIS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 531 AM CST MON FEB 24 2014
MIXED LOCAL LIFR/IFR/MVFR/LOCAL VFR THIS MORNING ARE EXPECTED TO
IMPROVE TO MVFR/VFR THIS AFTERNOON AND TONIGHT.
LOW CIGS AND VSBY ACROSS WRN NEB ARE EXPECTED TO IMPROVE TO VFR
THIS AFTERNOON AS THE RESULT OF A CLEARING LINE THAT IS EXPECTED
TO DEVELOP. THE CLEARING LINE COULD MOVE TO KIEN- KTIF- KLBF
BEFORE AN ARCTIC FRONT SWEEPS IN THIS AFTERNOON AND LOWERS CIGS TO
MVFR. A BAND OF LIGHT SNOW AND MVFR CIGS/VSBY IS EXPECTED TO
DEVELOP LATE THIS AFTERNOON AND THIS EVENING...MAINLY ACROSS WRN
NEB. THIS IS ASSOCIATED WITH THE PASSAGE OF THE ARCTIC FRONT.
SNOW AND MVFR/IFR CIGS ARE EXPECTED TO DEVELOP TODAY...GENERALLY
FROM KIEN-KTIF-KONL NORTHWARD WITH FLIGHT CONDITIONS WORSENING
NORTHWARD. FLIGHT CONDITIONS SHOULD IMPROVE WEST TO EAST LATE THIS
AFTERNOON AS THE DISTURBANCE TRACKING THROUGH SD MOVES EAST OF THE
AREA.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
350 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CST MON FEB 24 2014
1038 MB ARCTIC HIGH PRESSURE ACROSS SRN ALBERTA AND SRN
SASKATCHEWAN WILL MOVE INTO SOUTH DAKOTA BY 12Z TUESDAY MORNING.
AN ARCTIC FRONT ACROSS NRN MT IS EXPECTED TO MOVE INTO THE FCST
AREA BY LATE AFTN AND BE THROUGH THE FCST AREA AND ACROSS KS BY
TUESDAY MORNING. LOWS IN THE SINGLE DIGITS ARE EXPECTED TONIGHT
WITH WIND CHILL READINGS AROUND 10 BELOW TO PERHAPS 15 BELOW ZERO
ACROSS NORTHERN NEB.
THE MODEL CONSENSUS SUGGESTS A PERIOD OF LIGHT SNOW
DEVELOPING...MAINLY ACROSS WRN NEBRASKA...AS THE FRONT MOVES
THROUGH. SNOWFALL AMOUNTS SHOULD BE LESS THAN AN INCH AND MAINLY
A DUSTING.
THERE IS QUITE A VARIETY OF MAX TEMPERATURE FORECASTS TO CHOOSE
FROM TODAY. THE FORECAST FOLLOWS A BLEND OF NAM...GEM REG...ECM
AND MET PLUS BIAS CORRECTION FOR HIGHS IN THE UPPER 20S NORTH TO
UPPER 30S SOUTH. THE NAM IS ACTUALLY FORECASTING MID 40S AT NORTH
PLATTE WHILE THE RAP SHOWS UPPER 20S AND THE ECM MID 30S. THIS IS
A FUNCTION OF THE SKY COVER INDICATED IN THE MODELS AND SOME
SOLNS SHOW A PERIOD OF CLEARING AHEAD OF THE ARCTIC FRONT. THE
MODEL CONSENSUS SUGGESTS CLEARING ACROSS WRN/SWRN
NEB...KAIA-KOGA-KIML AS A RESULT OF SOME SOUTHWEST WINDS
DEVELOPING. EAST OF THAT AREA IT LOOKS LIKE ARCTIC DRAPE SHOULD
CONTINUE WITH SOUTH WINDS.
THE LIGHT TO MODERATE SNOW ON RADAR EARLY THIS MORNING ACROSS
NCNTL NEB IS MOVING RAPIDLY EAST AND SHOULD BE REPLACED BY A
SECOND AREA OF SNOW LATER THIS MORNING A BIT FARTHER NORTH AND
EAST. THIS SNOW IS CURRENTLY SHOWING ON THE KUNR RADAR ACROSS WRN
SD. THE MODELS GENERATE A THIRD AREA OF SNOW THIS AFTERNOON BUT
THIS SHOULD PASS MOSTLY NORTH AND EAST OF THE FORECAST AREA. THIS
AREA OF SNOW IS CURRENTLY ACROSS SERN MT.
BEST SNOWFALL IS EXPECTED ACROSS BOYD COUNTY WITH QPF RANGES FROM
LESS THAN 0.10 INCHES IN THE UKMET...GEF AND GFS TO 0.30 INCHES
IN THE NMM WEST. THIS IS A WIDE RANGE AND THE CONSENSUS IS AROUND
0.15 INCHES. A 15 TO 20 TO 1 SNOW RATIO WAS USED BASED ON THE
COBB METHODOLOGY. OBSERVED SNOWFALL SUNDAY AFTN AND SUNDAY NIGHT
WAS IN THIS RANGE. THE NAM CONTINUES TO ADVERTISE POCKETS OF
STRONG FRONTOGENESIS WHICH COULD LEAD TO BANDED SNOW DEVELOPMENT.
THIS HAS BEEN THE OPERATIVE MODE IN MANY INSTANCES OVER THE PAST
36 HOURS HOWEVER THE NAM...ARF AND NMM MODELS HAVE SHOWN POOR
SKILL FORECASTING THE LOCATION OF THESE BANDS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM CST MON FEB 24 2014
TEMPS FOR THE END OF FEBRUARY AND INTO MARCH WILL BE DOMINATED BY
COLD ARCTIC AIR WITH WELL BELOW NORMAL READINGS. WEDNESDAY LOOKS
TO BE THE ONLY DAY WE MAY BE WITHIN 10 DEGREES OF NORMAL FOR
HIGHS INTO THE NEXT WEEKEND. ALSO WILL SEE AN ACTIVE PERIOD WITH
SEVERAL CHANCES FOR SNOW THROUGHOUT THE WEEK AND INTO THE
WEEKEND.
TUESDAY WILL SEE ANOTHER DISTURBANCE DRIFTING ACROSS THE SW
PORTIONS OF THE CWA. BATTLE WILL BE BETWEEN RADIATION OF A HIGHER
LATE FEBRUARY SUN ANGLE AND SNOWFALL RATES...ON TOP OF A SNOW
PACK. PLOWED ROADS TODAY FOR THE MOST PART BECAME WET AND IN SOME
AREAS EVEN PARTIALLY DRIED...DESPITE CLOUDY SKIES. THINK CLOUDS
WILL BE THICKER LIMITING SOLAR IMPACT...HOWEVER MODELS ARE ONLY
PRODUCING LIGHT SNOW. DAYTIME SNOW OF A HALF INCH TO 1.5 INCHES
FOR THE MOST PART WITH A 15 TO 1 RATIO...HIGHEST ACROSS THE
SOUTHEASTERN PAN HANDLE AND SW NEB.
BY TUESDAY NIGHT ARCTIC HIGH PRESSURE WILL BE DRIFTING OVERHEAD.
CENTER CROSSES OVER THE CWA BETWEEN 04Z AND 09Z. BY 12Z THE HIGH
WILL BE TO THE SE WITH SOUTHWESTERLY WINDS TO BE ON THE
INCREASING...ALONG WITH WAA. LOWS INITIALLY EXPECTED WITH THE
CENTER OF THE HIGH OVERHEAD...EARLY IN THE NIGHT...HOWEVER WITH
THE EXPECTED SNOW PACK...DECOUPLING WILL KEEP WINDS FROM MIXING TO
THE GROUND UNTIL SUNRISE OR LATER. THIS MAY ALLOW A COUPLE OF
DEGREES FURTHER OF A DROP AFTER CENTER PASSES. EITHER
WAY...EXPECT LOWS TO FALL TO A FEW DEGREES ON EITHER SIDE OF ZERO.
WITH THE WAA FOR WED...HIGHS WILL REBOUND ABOVE FREEZING. WARMEST
GUIDANCE IS INTO THE 40S...HOWEVER THINK SNOW PACK WILL HOLD HIGHS
IN THE 30S.
NEXT COLD FRONT ARRIVES FOR THURSDAY WITH TEMPS TO TAKE A
DOWNWARD TREND. A COUPLE OF REINFORCING COLD FRONT WILL CONTINUE
TO TAKE TEMPS LOWER INTO THE WEEKEND. THIS WILL BE COUPLED WITH
SEVERAL DISTURBANCE TO RIDE ACROSS THE HIGH PLAINS WITH SEVERAL
CHANCES FOR SNOW. SNOW IS NOT EXPECTED TO BE CONSTANT...HOWEVER
CHANCES FOR AT LEAST LIGHT SNOW IN ANY 12 HOURS PERIOD WILL
RESULT IN MANY PERIODS WITH SNOW IN THE FORECAST.
NORMAL HIGHS THIS TIME OF YEAR SHOULD BE INTO THE 40S WITH LOWS
IN THE TEENS. MODELS ARE IN GOOD AGREEMENT WITH HIGHS ONLY IN THE
10S AND 20S FROM FRIDAY THROUGH THE WEEKEND AS THE COLD AIR
BLANKETS MUCH OF THE CONUS. COLDEST GUIDANCE IS THE EC WITH MANY
LOCATIONS NOT WARMING ABOVE SINGLE DIGITS FOR THE WEEKEND. THIS
IS NEARLY 40 DEGREES BELOW NORMAL. SUN ANGLE CONTINUES TO
INCREASE...AND RECORD LOW MAXES ARE IN THE SINGLE DIGITS...SO DO
NOT WANT TO GO WITH THE RECORD COLD FROM THE EC YET...THUS
FORECAST IS FAVORING A SLIGHTLY WARMER GFS AT THIS TIME. HOWEVER
WILL CONTINUE TO KEEP AN EYE ON THIS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1127 PM CST SUN FEB 23 2014
SURFACE WIND AND THE FIRST 1000M ABOVE THE SURFACE SHOW SOUTHEAST
WIND WHICH IS UPSLOPE. THE RESULT IS STRATUS WITH CEILING 1000
FEET AGL OR LOWER. THERE IS SOME UNCERTAINTY REGARDING HOW FAR
EAST IT WILL SPREAD. THE TERRAIN WOULD INDICATE THAT THE LOW
CEILINGS WOULD REACH TO JUST WEST OF VTN-TIF-LBF. STILL...IT WILL
BE CLOSE ENOUGH TO THOSE SITES TO JUSTIFY INCLUDING AT LEAST AN
INTERMITTENT CONDITION OF CEILING BELOW 1000 FEET AGL.
THE SNOW BANDS INDICATED ON RADAR ARE LIKELY TO STAY BETWEEN VTN
AND LBF. HOWEVER...THE HEAVIER SNOW WILL CONTINUE AT TIF...MHN AND
BBW UNTIL ABOUT 10Z WHEN THE CONDITIONS BECOME LESS FAVORABLE FOR
BANDED MODERATE TO HEAVY SNOW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1135 PM CST SUN FEB 23 2014
.UPDATE...
ISSUED AT 1135 PM CST SUN FEB 23 2014
NO CHANGES PLANNED TO LATE EVENING UPDATE. FORECAST LOOKS IN GOOD
SHAPE FOR EARLIER DECISION OF DELAYING WIND CHILL HEADLINES UNTIL
12 AM CST. DVL BASIN AREA NOW WELL WITHIN CRITERIA...WITH THE
NORTHERN VALLEY NEARING 25 BELOW. LAKE OF THE WOODS STILL QUITE
WARM BUT CLOUD COVER OVER AREA EXPECTED TO MOVE EAST IN THE 06Z TO
08Z TIMEFRAME.
UPDATE ISSUED AT 955 PM CST SUN FEB 23 2014
MAIN CHALLENGE FOR TONIGHT IS INHERITED WIND CHILL HEADLINES.
WARMEST TEMPS AS OF RIGHT NOW ARE OVER SOUTHEASTERN ND...AND
MODELS SHOWING RANSOM/SARGENT HAVING LIGHTEST WINDS TONIGHT AS
WELL (ALREADY AROUND 5KTS). WILL REMOVE THESE TWO COUNTIES FROM
ADVISORY AS WIND CHILLS ARE NOT EXPECTED TO REACH CRITERIA.
FOR THE REST OF THE AREA...WIND CHILLS NEARING CRITERIA WHERE
BREEZY WINDS ARE STILL GOING OVER NORTHEASTERN ND. EXPECT APPARENT
TEMPS IN THIS AREA TO WARM UP A BIT AS WINDS DIE DOWN...THEN BEGIN
FALLING AGAIN IN THE 06Z TO 09Z TIMEFRAME ALONG WITH THE REST OF
THE CWA. DELAYED COUNTIES OUTSIDE OF NORTHEASTER ND/NORTHERN RRV
UNTIL 12 AM BUT 3 AM IS THE MORE LIKELY TIMEFRAME FOR MEETING
ADVISORY CRITERIA. THIS WILL MATCH UP NICELY WITH NEIGHBORING WFOS
TO THE EAST AND SOUTH. NO OTHER CHANGES MADE TO THIS FCST.
FOR TOMORROW...THE LATEST NAM AND RUC CONTINUE TO BRING PRECIP
INTO THE SOUTHWESTERN ZONES AFTER NOON TIMEFRAME...WITH THE RUC
HAVING DRIER QPFS. LOOKS LIKE MOST SNOW SHOULD BE SOUTH OF THE HWY
200 CORRIDOR OR PERHAPS EVEN THE I 94 CORRIDOR. NO CHANGES TO POPS MADE.
UPDATE ISSUED AT 656 PM CST SUN FEB 23 2014
CLEAR SKIES ACROSS CWA TONIGHT...WITH WINDS STILL IN THE 15 TO 25
MPH RANGE FOR MUCH OF THE AREA. OVER THE NEXT COUPLE OF
HOURS...WINDS SHOULD BEGIN TO DIE OFF ENOUGH TO ALLOW TEMPS TO
BEGIN TO FALL YET HIGH ENOUGH TO BRING WIND CHILLS IN THE 25 BELOW
TO 35 BELOW RANGE. NO PLANNED CHANGES TO HEADLINES TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 325 PM CST SUN FEB 23 2014
CHALLENGES INCLUDE WIND CHILLS TONIGHT AND LOW PRECIPITATION
CHANCES TOMORROW. GLOBAL MODELS ARE IN GOOD AGREEMENT AND WILL USE
A BLENDED SOLUTION.
FOR TONIGHT...SCT-BKN CLOUD COVER WILL REMAIN CONFINED TO THE
NORTHEAST FORECAST AREA AS CLOUD DECK AROUND JAMES BAY LOW
CONTINUES TO PIVOT TO THE SOUTH. ALL OTHER AREAS WILL REMAIN
MOSTLY CLEAR AS SURFACE RIDGE BUILDS ACROSS EASTERN ND INTO
SOUTHWEST MN. CURRENT TEMPERATURES UNDER THIS RIDGE ARE IN THE
SINGLE DIGITS BELOW ZERO ACROSS ALBERTA AND SOUTHERN SASKATCHEWAN
AND THIS COLDER AIR MASS WILL BEGIN TO SAG SOUTHWARD OVERNIGHT.
NORTHWEST WIND WILL REMAIN ELEVATED BETWEEN 5 AND 10 MPH...BUT
TEMPERATURE GUIDANCE IN FAIR AGREEMENT SHOWING OVERNIGHT LOWS
DROPPING INTO THE LOW TEENS BELOW ZERO. AIR TEMPERATURES AND WINDS
WILL RESULT IN WIND CHILL VALUES FROM 25 TO 35 BELOW...SO WILL
ISSUE A CWA-WIDE WIND CHILL ADVISORY FROM 04 UTC TONIGHT UNTIL 16
UTC MONDAY.
SURFACE LOW WILL DIVE SOUTH ALONG THE LEE OF THE ROCKIES ON MONDAY
WITH WARM AIR ADVECTION SNOW DEVELOPING MAINLY ACROSS SD. NORTHERN
EXTENT OF THIS SNOW SHIELD MAY CLIP THE SOUTHERN FORECAST AREA...
SO WILL KEEP CHANCE POPS MAINLY ALONG AND SOUTH OF THE I-94/HWY 10
CORRIDOR. WAS ABLE TO REMOVE POPS MONDAY MORNING WITH SLOWER
FORWARD PROGRESSION IN THE MODELS. ANY ACCUMULATION WILL BE
MINIMAL...AROUND A HALF INCH OR LESS. TEMPERATURES TO BE A BIT
COOLER THAN TODAY...BUT STILL ABOVE ZERO WITH NORTHWEST WIND
BETWEEN 5 AND 15 MPH.
LINGERING SNOW SHOWERS POSSIBLE ACROSS SOUTHEAST FORECAST AREA
MONDAY NIGHT...WITH ALL OTHER AREAS DRY. MOSTLY CLEAR SKIES...
TEMPERATURES BELOW ZERO AND WIND AROUND 10 MPH WILL LIKELY
NECESSITATE ANOTHER WIND CHILL ADVISORY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 325 PM CST SUN FEB 23 2014
MORE OF THE SAME FOR TUESDAY AND WEDNESDAY AS 1035 TO 1040 HPA
SURFACE HIGH DROPS SOUTH FROM CANADA AND MOVES ACROSS THE NORTHERN
PLAINS. EXPECT MORE SUN THAN CLOUDS WITH PERSISTENT BREEZY
CONDITIONS FROM THE WEST-NORTHWEST. HIGH TEMPERATURES TUESDAY
AROUND THE ZERO MARK WILL WARM SLIGHTLY BY WEDNESDAY INTO THE
SINGLE DIGITS TO MID TEENS ABOVE ZERO. THE SEEMINGLY ENDLESS
STREAM OF WIND CHILL ADVISORIES WILL MOST LIKELY CONTINUE BOTH
TUESDAY AND WEDNESDAY NIGHT.
LONG RANGE MODELS CONTINUE TO ADVERTISE THE COLD POOL OF AIR SITTING
OVER CENTRAL CANADA INTO HUDSON BAY REGION DOWN INTO THE NORTH
CENTRAL UNITED STATES. SURFACE HIGH REMAINS FROM NORTH DAKOTA
INTO SASK. THUS FOR THE THURSDAY THROUGH SUNDAY PERIOD EXPECTING
WELL BELOW NORMAL TEMPERATURES BUT DRY CONDITIONS. MAY BE A LITTLE
LOW ON THURSDAY FEATURING RIDICULOUSLY COLD MAX TEMPS BUT LET RIDE
FOR NOW. ADDED A COUPLE OF DEGREES TO WEEKEND TEMPS...IF ECMWF IS
CORRECT IT WILL BE COLDER THOUGH AS IT ROTATES COLD POOL FROM
NORTHERN MANITOBA THROUGH WINNIPEG INTO MINNESOTA. FORECAST STILL
BARREN WITH RESPECT TO PRECIPITATION THROUGH SATURDAY WITH A SOUTH
TRACKING SYSTEM OFFERING SCANT POPS ACROSS THE FAR SOUTHWEST
BRIEFLY ON SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1135 PM CST SUN FEB 23 2014
VFR CONDS ACROSS AREA THROUGH 06Z TAF PERIOD...WITH EXCEPTION OF
FAR. MAY SEE SOME MVFR CIGS AND LIGHT SNOW IN THE LATE AFTN TO
EARLY EVENING HOURS TOMORROW. DID MENTION LIGHT SNOW AFT 22Z AS
MODELS HAVE CONSISTENTLY BROUGHT PRECIP ALONG AND SOUTH OF I 94
CORRIDOR. HAVE MAINTAINED LOW VFR CIGS AT DVL AND GFK BUT REMOVED
CIGS FROM TVF AND BJI AS SWATH OF CLOUDS SHOULD DROP SOUTH AS THEY
DRIFT EAST.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NDZ038-039-053.
WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR NDZ006>008-
014>016-024-026>030-054.
MN...WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR MNZ003-005-006-
008-009-013>017-022>024-027>032-040.
WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR MNZ001-002-004-
007.
&&
$$
UPDATE...SPEICHER
SHORT TERM...ROGERS
LONG TERM...ROGERS/WJB
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
930 PM CST TUE FEB 25 2014
.DISCUSSION...
CURRENT FORECAST IS IN GOOD SHAPE. NO UPDATE IS PLANNED FOR THE
OVERNIGHT HOURS. WILL WAIT FOR ALL OF THE 00Z MODELS TO ARRIVE
BEFORE ANY SIGNIFICANT CHANGES ARE MADE TO OUR RAIN CHANCES...WINDS
AND TEMPERATURES.
COLD FRONT IS SLOWLY WORKING ITS WAY THROUGH SOUTHEAST TEXAS THIS
EVENING...APPROACHING THE I-10 CORRIDOR AT AROUND 9 PM. AREAS OF
RAIN WITH EMBEDDED SHOWERS AND THUNDERSTORMS ARE DEVELOPING ACROSS
THE AREA...AND MODELS INDICATE THIS SHOULD CONTINUE OVERNIGHT AND
ON INTO TOMORROW MORNING (SOME SPOTS WITH THE HEAVIER STORMS HAVE
ALREADY RECEIVED 1 TO 2 INCHES). TEMPERATURES ARE IN THE LOW TO
MID 50S BEHIND THE FRONT UP NORTH...AND EXPECT THIS COOLER AIR TO
WORK ITS WAY TOWARD THE COAST OVERNIGHT. 42
&&
.PREV DISCUSSION... /ISSUED 609 PM CST TUE FEB 25 2014/
DISCUSSION...
00Z AVIATION DISCUSSION BELOW.
AVIATION...
THE SHORT TERM FORECAST...OR THROUGH THE EARLY WEDNESDAY MORNING
HOURS...WILL BE FOR INTERMITTENT SHOWERS WITH A ISOLATED STORM
AND STRENGTHENED NORTH WIND BEHIND AN EVENING COLD FRONTAL PASSAGE.
THE MAIN IMPULSE DRIVING THIS ONGOING WIDELY SCATTERED -SHRA (ISO
-TSRA) IS TRAVELING ACROSS NORTHERN TEXAS THIS EVENING WITH THE
ONLY TRIGGERS LEFT OVER IN THIS HIGHLY-MOIST ENVIRONMENT FOR
REPEAT PRECIPITATION BEING ANOTHER EASTERN PASSING SHORTWAVE
RIPPLE WITHIN THE WESTERLY FLOW AND/OR THE ENHANCED POST-FRONTAL
ISENTROPIC UPGLIDE AS SOUTHWESTERLY MID-UPPER FLOW RIDES UP AND
OVER A PUMPED UP NORTH-NORTHEAST LOWER LEVEL WIND. BETTER UPPER
DIFFULENCE BY TOMORROW AFTERNOON AS SE TX FALLS UNDER AN EXITING
RRQ JET. CONSIDERING THE ABOVE ELEMENTS AND...EVEN WITH NWP
MODELING NOT PROVIDING MUCH GUIDANCE UP TO NOW...STILL BELIEVE
THAT ALL WILL COME IN-LINE FOR BETTER OVERALL (LIGHT) RAIN
COVERAGE. PROBABLY NOT AN ALL-DAY RAIN EVENT...BUT GT 50% OF THE
TIME THERE WILL BE THAT PASSING SHOWER...BRIEF MODERATE RAINFALL
ASSOCIATED WITH STRONGER CELLS WEDNESDAY AFTERNOON...BUT THERE
WILL ALSO BE LONGER PERIODS OF A JUST A LIGHT MIST AND/OR DRIZZLE
ALONG WITH THOSE PESKY FLUCTUATING DECKS FROM IFR TO MVFR AND VICE
VERSA. 31
PREV DISCUSSION... /ISSUED 333 PM CST TUE FEB 25 2014/
DISCUSSION...
FRONT IS NOW PUSHING INTO NRN PORTIONS OF SE TX. SHOULD BE BETWEEN
I-10 AND THE COAST AROUND MIDNIGHT AND OFF THE BEACHES BY 4AM
(EFFECTIVELY ENDING SEA FOG ISSUES FOR A FEW DAYS). STARTING TO
SEE SOME SCT PRECIP DEVELOP ACROSS S PARTS OF THE AREA AND EXPECT
IT TO GRADUALLY INCREASE IN COVERAGE AHEAD OF, AND ESPECIALLY
BEHIND, THE FRONT. HRRR MODEL AND TO A DEGREE NAM12 HAS DONE
FAIRLY WELL WITH RAINFALL DEPICTION (OR LACK THEREOF) SO FAR TODAY
AND SHORT TERM FCST WAS TRENDED THAT WAY. GFS/ECMWF HAVE BEEN
HORRIBLY OVERDONE BOTH IN COVERAGE & AMOUNTS UP TO THIS TIME.
PERIODS OF PRECIP WILL LIKELY CONTINUE THRU WED IN ASSOCIATION
WITH H85 FRONT AND UPPER IMPULSES RIDING FURTHER OVERHEAD IN THE
WRLY FLOW ALOFT. CONSIDERING STRONG CAA...CLOUDINESS AND PRECIP
THE HIGHS FOR THE 24 HOUR PERIOD WILL OCCUR AROUND MIDNIGHT
FOLLOWED BY FALLING AND/OR STEADY TEMPS IN THE 40S WED. RAIN
SHOULD TAPER OFF WED EVENING.
COOL WX CONTINUES THURS BUT ONSHORE WIND WILL BE RESUMING AS HIGH
PRES MOVES EAST AND NEXT SHORTWAVE STARTS DIGGING SEWD DOWN THE
4-CORNERS AREA. THIS DISTURBANCE ISN`T AS IMPRESSIVE AS PREVIOUS
DAYS AND DON`T ANTICIPATE MUCH OF AN IMPACT HERE AS IT MOVES ALONG
THE RED RIVER FRIDAY...AS BEST ENERGY WILL BE WELL NORTH AND A
CAP SHOULD BE IN PLACE. FURTHER LOWERED POPS.
WARMING TREND CONTINUES THRU THE WEEKEND WITH ONSHORE FLOW IN
PLACE. APPEARS THAT WE`LL PROBABLY HAVE ANOTHER COASTAL FOG EVENT
BUT LOOKS LIKE MARDI GRAS PARADES SHOULD OTHERWISE BE DRY PRIOR TO
MID TO LATE SUNDAY AFTN. NEXT STORM SYSTEM APPROACHES FROM THE
WEST LATE IN THE WEEKEND AND KEPT 20-40% POPS IN PLACE SUN AFTN/NIGHT
AHEAD OF THE NEXT FRONT THAT`LL BE MOVING THRU SUNDAY NIGHT OR
MONDAY. KNOCKED TEMPS DOWN EARLY NEXT WEEK (MAYBE NOT ENOUGH) AS
1040+MB HIGH DROPS INTO THE PLAINS. 47
MARINE...
SEA FOG WILL CONTINUE OVER THE GULF WATERS THIS AFTERNOON. AM
EXPECTING THE FOG TO REDEVELOP AND BECOME DENSE OVER THE BAYS LATER
THIS AFTERNOON AND EVENING. THE FOG WILL CLEAR OUT BETWEEN MIDNIGHT
AND SUNRISE AS A COLD FRONT PUSHES THROUGH THE BAYS AND OFF THE
COAST. THE MODELS HAVE BEEN FAIRLY CONSISTENT THE PAST FEW DAYS AND
AM FAIRLY CONFIDENT ON THE TIMING. EXPECT THE FRONT TO MOVE THROUGH
THE BAYS BY AROUND 3 AM AND THEN BEYOND 20 NM OFFSHORE BY 4 AM. THE
12Z MODEL RUN AND GUIDANCE FROM THIS MORNING FORECASTED SLIGHTLY
HIGHER WINDS...INDICATING THAT SMALL CRAFT ADVISORIES ARE LIKELY FOR
THE GULF WATERS AND MATAGORDA BAY. WOULD NOT BE SURPRISED IF WINDS
INCREASE TO BETWEEN 20 AND 25 KNOTS FOR AT LEAST MOST OF THE LOWER
PART OF GALVESTON BAY...ALSO. EXPECT THE NORTHEASTERLY WINDS TO
DIMINISH WEDNESDAY NIGHT AND THURSDAY. ANOTHER FOG EVENT MAY DEVELOP
BY LATE THIS WEEK AS ONSHORE REDEVELOPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 43 33 57 42 / 70 60 20 10 10
HOUSTON (IAH) 49 49 36 59 43 / 70 70 30 10 10
GALVESTON (GLS) 54 54 42 55 53 / 70 60 40 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 4 AM CST WEDNESDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 6 AM TO NOON CST WEDNESDAY FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT SHOULD EXERCISE CAUTION WEDNESDAY AFTERNOON FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM CST WEDNESDAY FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM WEDNESDAY EVENING
THROUGH LATE WEDNESDAY NIGHT FOR THE FOLLOWING ZONES:
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20
NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 6 AM WEDNESDAY TO MIDNIGHT CST
WEDNESDAY NIGHT FOR THE FOLLOWING ZONES: WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...
WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION LATE WEDNESDAY NIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...42
AVIATION/MARINE...31
AREA FORECAST DISCUSSION...UPDATED
NWS HOUSTON/GALVESTON TX
609 PM CST TUE FEB 25 2014
.DISCUSSION...
00Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
THE SHORT TERM FORECAST...OR THROUGH THE EARLY WEDNESDAY MORNING
HOURS...WILL BE FOR INTERMITTENT SHOWERS WITH A ISOLATED STORM
AND STRENGTHENED NORTH WIND BEHIND AN EVENING COLD FRONTAL PASSAGE.
THE MAIN IMPULSE DRIVING THIS ONGOING WIDELY SCATTERED -SHRA (ISO
-TSRA) IS TRAVELING ACROSS NORTHERN TEXAS THIS EVENING WITH THE
ONLY TRIGGERS LEFT OVER IN THIS HIGHLY-MOIST ENVIRONMENT FOR
REPEAT PRECIPITATION BEING ANOTHER EASTERN PASSING SHORTWAVE
RIPPLE WITHIN THE WESTERLY FLOW AND/OR THE ENHANCED POST-FRONTAL
ISENTROPIC UPGLIDE AS SOUTHWESTERLY MID-UPPER FLOW RIDES UP AND
OVER A PUMPED UP NORTH-NORTHEAST LOWER LEVEL WIND. BETTER UPPER
DIFFULENCE BY TOMORROW AFTERNOON AS SE TX FALLS UNDER AN EXITING
RRQ JET. CONSIDERING THE ABOVE ELEMENTS AND...EVEN WITH NWP
MODELING NOT PROVIDING MUCH GUIDANCE UP TO NOW...STILL BELIEVE
THAT ALL WILL COME IN-LINE FOR BETTER OVERALL (LIGHT) RAIN
COVERAGE. PROBABLY NOT AN ALL-DAY RAIN EVENT...BUT GT 50% OF THE
TIME THERE WILL BE THAT PASSING SHOWER...BRIEF MODERATE RAINFALL
ASSOCIATED WITH STRONGER CELLS WEDNESDAY AFTERNOON...BUT THERE
WILL ALSO BE LONGER PERIODS OF A JUST A LIGHT MIST AND/OR DRIZZLE
ALONG WITH THOSE PESKY FLUCTUATING DECKS FROM IFR TO MVFR AND VICE
VERSA. 31
&&
.PREV DISCUSSION... /ISSUED 333 PM CST TUE FEB 25 2014/
DISCUSSION...
FRONT IS NOW PUSHING INTO NRN PORTIONS OF SE TX. SHOULD BE BETWEEN
I-10 AND THE COAST AROUND MIDNIGHT AND OFF THE BEACHES BY 4AM
(EFFECTIVELY ENDING SEA FOG ISSUES FOR A FEW DAYS). STARTING TO
SEE SOME SCT PRECIP DEVELOP ACROSS S PARTS OF THE AREA AND EXPECT
IT TO GRADUALLY INCREASE IN COVERAGE AHEAD OF, AND ESPECIALLY
BEHIND, THE FRONT. HRRR MODEL AND TO A DEGREE NAM12 HAS DONE
FAIRLY WELL WITH RAINFALL DEPICTION (OR LACK THEREOF) SO FAR TODAY
AND SHORT TERM FCST WAS TRENDED THAT WAY. GFS/ECMWF HAVE BEEN
HORRIBLY OVERDONE BOTH IN COVERAGE & AMOUNTS UP TO THIS TIME.
PERIODS OF PRECIP WILL LIKELY CONTINUE THRU WED IN ASSOCIATION
WITH H85 FRONT AND UPPER IMPULSES RIDING FURTHER OVERHEAD IN THE
WRLY FLOW ALOFT. CONSIDERING STRONG CAA...CLOUDINESS AND PRECIP
THE HIGHS FOR THE 24 HOUR PERIOD WILL OCCUR AROUND MIDNIGHT
FOLLOWED BY FALLING AND/OR STEADY TEMPS IN THE 40S WED. RAIN
SHOULD TAPER OFF WED EVENING.
COOL WX CONTINUES THURS BUT ONSHORE WIND WILL BE RESUMING AS HIGH
PRES MOVES EAST AND NEXT SHORTWAVE STARTS DIGGING SEWD DOWN THE
4-CORNERS AREA. THIS DISTURBANCE ISN`T AS IMPRESSIVE AS PREVIOUS
DAYS AND DON`T ANTICIPATE MUCH OF AN IMPACT HERE AS IT MOVES ALONG
THE RED RIVER FRIDAY...AS BEST ENERGY WILL BE WELL NORTH AND A
CAP SHOULD BE IN PLACE. FURTHER LOWERED POPS.
WARMING TREND CONTINUES THRU THE WEEKEND WITH ONSHORE FLOW IN
PLACE. APPEARS THAT WE`LL PROBABLY HAVE ANOTHER COASTAL FOG EVENT
BUT LOOKS LIKE MARDI GRAS PARADES SHOULD OTHERWISE BE DRY PRIOR TO
MID TO LATE SUNDAY AFTN. NEXT STORM SYSTEM APPROACHES FROM THE
WEST LATE IN THE WEEKEND AND KEPT 20-40% POPS IN PLACE SUN AFTN/NIGHT
AHEAD OF THE NEXT FRONT THAT`LL BE MOVING THRU SUNDAY NIGHT OR
MONDAY. KNOCKED TEMPS DOWN EARLY NEXT WEEK (MAYBE NOT ENOUGH) AS
1040+MB HIGH DROPS INTO THE PLAINS. 47
&&
MARINE...
SEA FOG WILL CONTINUE OVER THE GULF WATERS THIS AFTERNOON. AM
EXPECTING THE FOG TO REDEVELOP AND BECOME DENSE OVER THE BAYS LATER
THIS AFTERNOON AND EVENING. THE FOG WILL CLEAR OUT BETWEEN MIDNIGHT
AND SUNRISE AS A COLD FRONT PUSHES THROUGH THE BAYS AND OFF THE
COAST. THE MODELS HAVE BEEN FAIRLY CONSISTENT THE PAST FEW DAYS AND
AM FAIRLY CONFIDENT ON THE TIMING. EXPECT THE FRONT TO MOVE THROUGH
THE BAYS BY AROUND 3 AM AND THEN BEYOND 20 NM OFFSHORE BY 4 AM. THE
12Z MODEL RUN AND GUIDANCE FROM THIS MORNING FORECASTED SLIGHTLY
HIGHER WINDS...INDICATING THAT SMALL CRAFT ADVISORIES ARE LIKELY FOR
THE GULF WATERS AND MATAGORDA BAY. WOULD NOT BE SURPRISED IF WINDS
INCREASE TO BETWEEN 20 AND 25 KNOTS FOR AT LEAST MOST OF THE LOWER
PART OF GALVESTON BAY...ALSO. EXPECT THE NORTHEASTERLY WINDS TO
DIMINISH WEDNESDAY NIGHT AND THURSDAY. ANOTHER FOG EVENT MAY DEVELOP
BY LATE THIS WEEK AS ONSHORE REDEVELOPS. 40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 43 33 57 42 / 70 60 20 10 10
HOUSTON (IAH) 49 49 36 59 43 / 70 70 30 10 10
GALVESTON (GLS) 54 54 42 55 53 / 70 60 40 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 4 AM CST WEDNESDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20
TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...42
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1023 PM PST Sun Feb 23 2014
.SYNOPSIS...
Periods of snow will continue tonight. Snow showers will linger
through Monday, mainly over the Cascades, Blue Mountains, and the
Idaho Panhandle. A subtle warming trend is expected Tuesday
through Thursday with temperatures near average for the second
half of the work week. Next weekend has the potential to be colder
with a chance of more snow.
&&
.DISCUSSION...
Ended some of the winter weather advisories, decreased pops in
those same areas, and slightly cooled forecast low temperatures
tonight with a late evening update. Radar and HRRR runs suggest
the back edge of the exiting swath of snowfall is slowly moving to
the southeast and exited those area to the north. Some light
precipitation may still fall on those locations but since no
further significant accumulations were expected tonight those
highlights were ended. Locations to the south and east near the
Palouse and down to the Camas Prairie are still susceptible to the
northwest to southeast trajectory of exit associated with this
disturbances so those advisories along with the winter storm
warning for the Idaho Central Panhandle Mountains have been
maintained with some slight modification to the accumulation
amounts and more wording to reference the very slick road
conditions when pavement temperatures dropped below freezing near
and shortly after sundown today. Additionally some fog was added
to the forecast earlier on, primarily as it appeared in proximity
to the more intense snow of this evening but right now it seems to
have gone and mostly low stratus has taken its place. /Pelatti
&&
.AVIATION...
06Z TAFS: Slow exit to the southeast of a weather disturbance
bringing mostly snow to majority of aviation areas allows for
primarily IFR ceilings to linger as most of the intense snowfall has
already occurred and/or moving out of the area to the southeast. Fog
has accompanied the snow at times. A weak frontal may very well
allow snow to intensify near the Palouse early Monday morning
ahead of yet another weather system coming up from the south which
will allow a good part of the time interval after 03Z Tuesday down
south to become wet as well with more rain/snow. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 20 31 18 32 19 39 / 20 10 10 0 0 0
Coeur d`Alene 18 30 16 33 14 38 / 40 10 10 0 0 0
Pullman 27 33 25 39 25 42 / 80 50 40 20 10 10
Lewiston 33 40 29 43 29 47 / 90 40 50 20 10 10
Colville 16 32 16 37 12 40 / 20 10 10 0 0 0
Sandpoint 14 28 14 31 11 35 / 20 10 10 0 0 0
Kellogg 16 29 17 34 13 39 / 100 40 30 10 0 0
Moses Lake 27 38 26 41 23 43 / 20 10 20 10 10 0
Wenatchee 27 35 25 38 24 40 / 50 40 30 10 10 10
Omak 21 33 22 36 18 38 / 20 20 10 0 0 0
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 10 AM PST Monday for Idaho Palouse.
Winter Storm Warning until 10 AM PST Monday for Central
Panhandle Mountains.
Winter Weather Advisory until 10 AM PST Monday for Lewis and
Southern Nez Perce Counties.
WA...Winter Weather Advisory until 4 AM PST Monday for East Slopes
Northern Cascades.
Winter Weather Advisory until 10 AM PST Monday for Washington
Palouse.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1131 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CST MON FEB 24 2014
...CURRENTLY AS OF 09Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING ALONG
THE U.S. WEST COAST NORTHWARD THROUGH ALASKA...WHILE TROUGHING
DOMINATED FROM THE NORTH POLE SOUTHWARD THROUGH MUCH OF CANADA AND
THE NORTHERN TIER OF THE U.S.. WITHIN THIS TROUGHING...THERE ARE 3
IMPORTANT SHORTWAVE TROUGHS OF NOTE FOR THE FORECAST...
1. OVER SOUTHERN SASKATCHEWAN INTO NORTHWEST MONTANA...EXPECTED
TO BRING THE SNOW LATE TODAY INTO TONIGHT. DPVA AND ISENTROPIC
LIFT AHEAD OF THIS SHORTWAVE HAS SUPPORTED LIGHT SNOW ACROSS MUCH
OF MONTANA SOUTHEAST INTO NEBRASKA.
2. ALONG THE NUNAVUT/NORTHWEST TERRITORIES BORDER IN CANADA...
EXPECTED TO BRING THE ARCTIC COLD SHOT TO THE AREA TUESDAY NIGHT.
IN ITS WAKE SURFACE TEMPERATURES RANGE FROM A BITTER 20 TO 30
BELOW ZERO.
3. RIGHT NEAR THE NORTH POLE...SPECIFICALLY 84 N / 130 W...EXPECTED
TO BRING THE ARCTIC AIR FOR THURSDAY INTO THE WEEKEND. IN ITS
WAKE... 925MB TEMPS RANGE FROM -28 TO -34C PER GFS ANALYSIS.
OVER THE FORECAST AREA...SKIES REMAIN CLEAR DUE TO PLENTY OF DRY AIR
AS SEEN ON THE 00Z MPX SOUNDING. SOME CIRRUS IS BEGINNING TO
ENCROACH FROM THE WEST...THOUGH. TEMPERATURES HAVE SLOWLY COOLED
THROUGH THE NIGHT RESULTING FROM A WESTERLY BREEZE...WITH READINGS
IN THE LOWER SINGLE DIGITS.
... FORECAST ...
MODELS ARE IN GOOD AGREEMENT MARCHING THE FIRST SHORTWAVE TROUGH
INTO THE EASTERN DAKOTAS BY 00Z...OVER THE FORECAST AREA BY 06Z AND
INTO LOWER MICHIGAN BY 12Z TUE. 275-280K ISENTROPIC LIFT PROGS
SUGGEST THAT TO GET THE SNOW OVER MONTANA AND NEBRASKA INTO THE
FORECAST AREA...WE HAVE TO WAIT FOR THE SHORTWAVE TROUGH TO ARRIVE.
THIS IS WHY MODELS SLOWED DOWN OVER THE PAST FEW DAYS OF BRINGING
SNOW TO THE AREA. THE BEST LIFT...ALBEIT WEAK...IS PROGGED OVER THE
SOUTHWESTERN HALF OF THE FORECAST AREA BETWEEN 01-06Z...THEN SHIFTS
TO FAR SOUTHWEST WI BETWEEN 06-09Z BEFORE EXITING. PRECIPITATION
CHANCES HAVE BEEN ADJUSTED TO FIT THE TIMING OF THE LIFT SIGNAL.
STILL DOES NOT LOOK LIKE THERE WILL BE MUCH SNOW GIVEN THE WEAK
NATURE OF THE LIFT...PRECIPITABLE WATER ONLY 0.1-0.2 OF AN
INCH...AND THE SNOW RUNNING INTO THE DRY AIRMASS CURRENTLY IN PLACE.
ANY LIFT TOO IS MOSTLY ABOVE THE DENDRITIC GROWTH ZONE. PREVIOUS
FORECAST AMOUNTS OF LESS THAN 1 INCH SEEM REASONABLE.
REGARDING TEMPERATURES. 925MB READINGS AT 18Z TODAY ARE SIMILAR TO
YESTERDAY AT 18Z...BETWEEN -13 AND -16C. ONLY DIFFERENCES BETWEEN
TODAY AND YESTERDAY IS MORE CLOUD COVER AND STARTING OFF COLDER...
WHICH SHOULD KEEP HIGHS A LITTLE COOLER. IN THE WAKE OF THE
SHORTWAVE TROUGH PASSAGE TONIGHT...925MB TEMPS COOL TO -14 TO -19C.
A NORTHWEST BREEZE COMBINED WITH CLOUDS SHOULD HELP TO HOLD LOWS UP
SOMEWHAT...BUT READINGS SHOULD FALL INTO THE SINGLE DIGITS ABOVE AND
BELOW ZERO THROUGH ADVECTION...COLDEST OVER THE NORTHWEST HALF OF
THE FORECAST AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 300 AM CST MON FEB 24 2014
THE BIG IMPACT STORY HERE IS THE COLD...
SHORTWAVE TROUGH CURRENTLY OVER THE NUNAVUT/NORTHWEST TERRITORIES
REGION IS PROGGED TO DROP THROUGH THE FORECAST AREA LATE
TUESDAY...USHERING IN THE FIRST SURGE OF BITTER COLD ARCTIC AIR.
TROUGH SHOULD GO THROUGH PRECIP FREE WITH JUST SOME CLOUDS. 925MB
TEMPS PLUMMET TO -21 TO -24C BY 06Z WEDNESDAY...SENDING SURFACE
TEMPERATURES DOWN BELOW ZERO. WITH THE COLD AIR FIRMLY ENTRENCHED
FOR 06-12Z...TEMPERATURES SHOULD IN MOST LOCATIONS DIP INTO TEENS
BELOW ZERO. MOS GUIDANCE WIND FORECASTS SUGGEST THE TYPICAL COLD
SPOTS COULD DECOUPLE...THUS HAVE THEM APPROACHING 20 BELOW. A WIND
CHILL ADVISORY IS A GIVEN FOR TUESDAY NIGHT INTO WEDNESDAY MORNING.
A BRIEF BREAK IN THE COLD AIR COMES WEDNESDAY AFTERNOON AS WESTERLY
WINDS INCREASE AND PULL IN SOME DOWNSLOPED AIR OFF THE ROCKIES. THIS
INCREASE IS A RESULT OF THE NEXT SHORTWAVE TROUGH NEAR THE NORTH
POLE DROPPING INTO THE MN ARROWHEAD. 925MB WINDS APPROACH 45-50 KT
AT 00Z THURSDAY WEST OF THE MISSISSIPPI RIVER...BRINGING UP CONCERN
OF A POSSIBLE WIND ADVISORY. HOWEVER...A STRONG INVERSION LOOKS TO
DEVELOP TO PRECLUDE MIXING THOSE HIGHER WINDS DOWN. IT STILL WILL BE
BRISK...THOUGH...AND STRONG ENOUGH TO RESULT IN SOME BLOWING AND
DRIFTING OF SNOW IN OPEN AREAS.
NEXT ARCTIC COLD SHOT WHICH IS MUCH MORE IMPRESSIVE COMES IN LATE
WEDNESDAY NIGHT. THE AFOREMENTIONED NORTH POLE SHORTWAVE CROSSES
UPPER MICHIGAN WEDNESDAY NIGHT...DRAGGING AN ARCTIC COLD FRONT
THROUGH THE FORECAST AREA. A STRONG PRESSURE RISE IS PROGGED BEHIND
THIS FRONT WHICH SHOULD RESULT IN A PERIOD OF BRISK NORTHWEST WINDS.
THEN 925MB TEMPS PLUMMET TO -23 TO -27C AT 12Z THURSDAY. DID NOT GO
AS COLD AS THESE WOULD SUGGEST GIVEN THE LATE ARRIVAL OF THE COLD
AIR AND PLENTY OF WIND. STILL...THE WIND CHILLS ARE PLENTY LOW
ENOUGH FOR AN ADVISORY.
THURSDAY AND THURSDAY NIGHT LOOK DOWNRIGHT COLD. 850MB TEMP
ANOMALIES ARE PROGGED BETWEEN 2.5-3 STANDARD DEVIATIONS BELOW
NORMAL...SUGGESTING RECORD TERRITORY. IN ADDITION...HIGH PRESSURE
SETTLES OVERHEAD THURSDAY NIGHT...SETTING UP POTENTIAL FOR
TEMPERATURES TO TANK. ONLY CAVEAT WILL BE SOME INCREASING MID/HIGH
CLOUDS LATER THURSDAY NIGHT. SOME WISCONSIN COLD SPOTS COULD DIP TO
30 BELOW OR COLDER...AS INDICATED BY THE MEX GUIDANCE.
FOR FRIDAY THROUGH MONDAY...THE FORECAST AREA WILL BE IN-BETWEEN
ARCTIC COLD UPPER TROUGHING ENCOMPASSING MUCH OF SOUTHERN CANADA AND
SHORTWAVE TROUGHS TRAVERSING THE SOUTHERN 2/3 OF THE U.S.. AT THE
SAME TIME AT THE SURFACE...ARCTIC HIGH PRESSURE SHOULD BE IN PLACE
FOR MUCH OF THE TIME. ONE SHORTWAVE MAY BRING SOME LIGHT SNOW TO
LOCATIONS SOUTH OF I-90 ON FRIDAY...IF IT CAN MAKE IT THROUGH THE
DRY AIR. ONLY KEPT 20 PERCENT CHANCES IN FOR THIS TIME PERIOD. SAME
HOLDS TRUE FOR ANOTHER SHORTWAVE TROUGH GOING BY SATURDAY NIGHT INTO
SUNDAY...THOUGH THE TRACK IS A BIT FARTHER NORTH SO CHANCES ARE A
LITTLE HIGHER. TEMPERATURES WILL STAY WELL BELOW NORMAL BEING UNDER
THE INFLUENCE OF THE ARCTIC SURFACE HIGH...THOUGH SOME GRADUAL
MODERATION SHOULD TAKE PLACE AS THE EARLY MARCH SUN WORKS ON THE
AIR. MORE WIND CHILL ADVISORIES ARE LIKELY...THOUGH...ESPECIALLY
FRIDAY NIGHT INTO SATURDAY MORNING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1131 AM CST MON FEB 24 2014
WEATHER SYSTEM TO TRACK SOUTHWEST OF THE TAF SITES THIS
EVENING...AND WILL LIKELY SPREAD LIGHT SNOW ACROSS KRST/KLSE AS IT
PASSES. TIMING WISE...LOOK FOR THE HEART OF THE FALLING SNOW TO BE
CENTERED AROUND 03Z...AND SHOULD ONLY LAST 2-4 HOURS AT EITHER
LOCATION. IFR VISIBILITIES EXPECTED AT KRST...WHERE THE BETTER
FORCING AND SATURATION WILL EXIST. AT KLSE...SIGNIFICANT AMOUNT OF
DRY AIR IN PLACE COUPLED WITH WEAKER FORCING SHOULD LIMIT
RESTRICTIONS. CEILINGS LIKELY TO REMAIN AT OR ABOVE 2000 FT
THROUGH THE PERIOD. ONCE THE SYSTEM DEPARTS OVERNIGHT...LINGERING
MOISTURE TRAPPED UNDER A LOW LEVEL INVERSION WILL KEEP CLOUDS IN
PLACE THROUGH 12Z. FINALLY...PUSH OF DRIER TUESDAY MORNING WILL
SCATTER REMAINING CLOUDS OUT AND MIXING UP TO 925 MB SHOULD MAKE
FOR SOME LATE MORNING / AFTERNOON GUSTS UP TO 20-22 KTS AT KRST.
&&
.CLIMATE...
ISSUED AT 300 AM CST MON FEB 24 2014
GIVEN ALL THE COLD AIR TO ROUND OUT THE MONTH OF FEBRUARY...HERE IS
HOW FEBRUARY AND THE WINTER OVERALL WOULD STACK UP COMPARED TO
RECORDS BASED ON THE CURRENT FORECAST...
...FOR THE MONTH OF FEBRUARY...
LA CROSSE... 9.3 AVERAGE TEMPERATURE...3RD COLDEST
COLDER FEBRUARYS...
1873... 3.9
1936... 4.3
ROCHESTER... 6.7 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1936... 0.5
1979... 5.7
1917... 6.0
...FOR THE WINTER...DECEMBER THROUGH FEBRUARY...
LA CROSSE... 11.5 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1872-1873... 8.4
1874-1875... 10.5
1977-1978... 11.4
1935-1936... 11.4
ROCHESTER... 8.8 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1978-1979... 5.6
1886-1887... 5.9
1935-1936... 8.1
1977-1978... 8.7
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION...ZT
CLIMATE......AJ/RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
605 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CST MON FEB 24 2014
...CURRENTLY AS OF 09Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING ALONG
THE U.S. WEST COAST NORTHWARD THROUGH ALASKA...WHILE TROUGHING
DOMINATED FROM THE NORTH POLE SOUTHWARD THROUGH MUCH OF CANADA AND
THE NORTHERN TIER OF THE U.S.. WITHIN THIS TROUGHING...THERE ARE 3
IMPORTANT SHORTWAVE TROUGHS OF NOTE FOR THE FORECAST...
1. OVER SOUTHERN SASKATCHEWAN INTO NORTHWEST MONTANA...EXPECTED
TO BRING THE SNOW LATE TODAY INTO TONIGHT. DPVA AND ISENTROPIC
LIFT AHEAD OF THIS SHORTWAVE HAS SUPPORTED LIGHT SNOW ACROSS MUCH
OF MONTANA SOUTHEAST INTO NEBRASKA.
2. ALONG THE NUNAVUT/NORTHWEST TERRITORIES BORDER IN CANADA...
EXPECTED TO BRING THE ARCTIC COLD SHOT TO THE AREA TUESDAY NIGHT.
IN ITS WAKE SURFACE TEMPERATURES RANGE FROM A BITTER 20 TO 30
BELOW ZERO.
3. RIGHT NEAR THE NORTH POLE...SPECIFICALLY 84 N / 130 W...EXPECTED
TO BRING THE ARCTIC AIR FOR THURSDAY INTO THE WEEKEND. IN ITS
WAKE... 925MB TEMPS RANGE FROM -28 TO -34C PER GFS ANALYSIS.
OVER THE FORECAST AREA...SKIES REMAIN CLEAR DUE TO PLENTY OF DRY AIR
AS SEEN ON THE 00Z MPX SOUNDING. SOME CIRRUS IS BEGINNING TO
ENCROACH FROM THE WEST...THOUGH. TEMPERATURES HAVE SLOWLY COOLED
THROUGH THE NIGHT RESULTING FROM A WESTERLY BREEZE...WITH READINGS
IN THE LOWER SINGLE DIGITS.
... FORECAST ...
MODELS ARE IN GOOD AGREEMENT MARCHING THE FIRST SHORTWAVE TROUGH
INTO THE EASTERN DAKOTAS BY 00Z...OVER THE FORECAST AREA BY 06Z AND
INTO LOWER MICHIGAN BY 12Z TUE. 275-280K ISENTROPIC LIFT PROGS
SUGGEST THAT TO GET THE SNOW OVER MONTANA AND NEBRASKA INTO THE
FORECAST AREA...WE HAVE TO WAIT FOR THE SHORTWAVE TROUGH TO ARRIVE.
THIS IS WHY MODELS SLOWED DOWN OVER THE PAST FEW DAYS OF BRINGING
SNOW TO THE AREA. THE BEST LIFT...ALBEIT WEAK...IS PROGGED OVER THE
SOUTHWESTERN HALF OF THE FORECAST AREA BETWEEN 01-06Z...THEN SHIFTS
TO FAR SOUTHWEST WI BETWEEN 06-09Z BEFORE EXITING. PRECIPITATION
CHANCES HAVE BEEN ADJUSTED TO FIT THE TIMING OF THE LIFT SIGNAL.
STILL DOES NOT LOOK LIKE THERE WILL BE MUCH SNOW GIVEN THE WEAK
NATURE OF THE LIFT...PRECIPITABLE WATER ONLY 0.1-0.2 OF AN
INCH...AND THE SNOW RUNNING INTO THE DRY AIRMASS CURRENTLY IN PLACE.
ANY LIFT TOO IS MOSTLY ABOVE THE DENDRITIC GROWTH ZONE. PREVIOUS
FORECAST AMOUNTS OF LESS THAN 1 INCH SEEM REASONABLE.
REGARDING TEMPERATURES. 925MB READINGS AT 18Z TODAY ARE SIMILAR TO
YESTERDAY AT 18Z...BETWEEN -13 AND -16C. ONLY DIFFERENCES BETWEEN
TODAY AND YESTERDAY IS MORE CLOUD COVER AND STARTING OFF COLDER...
WHICH SHOULD KEEP HIGHS A LITTLE COOLER. IN THE WAKE OF THE
SHORTWAVE TROUGH PASSAGE TONIGHT...925MB TEMPS COOL TO -14 TO -19C.
A NORTHWEST BREEZE COMBINED WITH CLOUDS SHOULD HELP TO HOLD LOWS UP
SOMEWHAT...BUT READINGS SHOULD FALL INTO THE SINGLE DIGITS ABOVE AND
BELOW ZERO THROUGH ADVECTION...COLDEST OVER THE NORTHWEST HALF OF
THE FORECAST AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 300 AM CST MON FEB 24 2014
THE BIG IMPACT STORY HERE IS THE COLD...
SHORTWAVE TROUGH CURRENTLY OVER THE NUNAVUT/NORTHWEST TERRITORIES
REGION IS PROGGED TO DROP THROUGH THE FORECAST AREA LATE
TUESDAY...USHERING IN THE FIRST SURGE OF BITTER COLD ARCTIC AIR.
TROUGH SHOULD GO THROUGH PRECIP FREE WITH JUST SOME CLOUDS. 925MB
TEMPS PLUMMET TO -21 TO -24C BY 06Z WEDNESDAY...SENDING SURFACE
TEMPERATURES DOWN BELOW ZERO. WITH THE COLD AIR FIRMLY ENTRENCHED
FOR 06-12Z...TEMPERATURES SHOULD IN MOST LOCATIONS DIP INTO TEENS
BELOW ZERO. MOS GUIDANCE WIND FORECASTS SUGGEST THE TYPICAL COLD
SPOTS COULD DECOUPLE...THUS HAVE THEM APPROACHING 20 BELOW. A WIND
CHILL ADVISORY IS A GIVEN FOR TUESDAY NIGHT INTO WEDNESDAY MORNING.
A BRIEF BREAK IN THE COLD AIR COMES WEDNESDAY AFTERNOON AS WESTERLY
WINDS INCREASE AND PULL IN SOME DOWNSLOPED AIR OFF THE ROCKIES. THIS
INCREASE IS A RESULT OF THE NEXT SHORTWAVE TROUGH NEAR THE NORTH
POLE DROPPING INTO THE MN ARROWHEAD. 925MB WINDS APPROACH 45-50 KT
AT 00Z THURSDAY WEST OF THE MISSISSIPPI RIVER...BRINGING UP CONCERN
OF A POSSIBLE WIND ADVISORY. HOWEVER...A STRONG INVERSION LOOKS TO
DEVELOP TO PRECLUDE MIXING THOSE HIGHER WINDS DOWN. IT STILL WILL BE
BRISK...THOUGH...AND STRONG ENOUGH TO RESULT IN SOME BLOWING AND
DRIFTING OF SNOW IN OPEN AREAS.
NEXT ARCTIC COLD SHOT WHICH IS MUCH MORE IMPRESSIVE COMES IN LATE
WEDNESDAY NIGHT. THE AFOREMENTIONED NORTH POLE SHORTWAVE CROSSES
UPPER MICHIGAN WEDNESDAY NIGHT...DRAGGING AN ARCTIC COLD FRONT
THROUGH THE FORECAST AREA. A STRONG PRESSURE RISE IS PROGGED BEHIND
THIS FRONT WHICH SHOULD RESULT IN A PERIOD OF BRISK NORTHWEST WINDS.
THEN 925MB TEMPS PLUMMET TO -23 TO -27C AT 12Z THURSDAY. DID NOT GO
AS COLD AS THESE WOULD SUGGEST GIVEN THE LATE ARRIVAL OF THE COLD
AIR AND PLENTY OF WIND. STILL...THE WIND CHILLS ARE PLENTY LOW
ENOUGH FOR AN ADVISORY.
THURSDAY AND THURSDAY NIGHT LOOK DOWNRIGHT COLD. 850MB TEMP
ANOMALIES ARE PROGGED BETWEEN 2.5-3 STANDARD DEVIATIONS BELOW
NORMAL...SUGGESTING RECORD TERRITORY. IN ADDITION...HIGH PRESSURE
SETTLES OVERHEAD THURSDAY NIGHT...SETTING UP POTENTIAL FOR
TEMPERATURES TO TANK. ONLY CAVEAT WILL BE SOME INCREASING MID/HIGH
CLOUDS LATER THURSDAY NIGHT. SOME WISCONSIN COLD SPOTS COULD DIP TO
30 BELOW OR COLDER...AS INDICATED BY THE MEX GUIDANCE.
FOR FRIDAY THROUGH MONDAY...THE FORECAST AREA WILL BE IN-BETWEEN
ARCTIC COLD UPPER TROUGHING ENCOMPASSING MUCH OF SOUTHERN CANADA AND
SHORTWAVE TROUGHS TRAVERSING THE SOUTHERN 2/3 OF THE U.S.. AT THE
SAME TIME AT THE SURFACE...ARCTIC HIGH PRESSURE SHOULD BE IN PLACE
FOR MUCH OF THE TIME. ONE SHORTWAVE MAY BRING SOME LIGHT SNOW TO
LOCATIONS SOUTH OF I-90 ON FRIDAY...IF IT CAN MAKE IT THROUGH THE
DRY AIR. ONLY KEPT 20 PERCENT CHANCES IN FOR THIS TIME PERIOD. SAME
HOLDS TRUE FOR ANOTHER SHORTWAVE TROUGH GOING BY SATURDAY NIGHT INTO
SUNDAY...THOUGH THE TRACK IS A BIT FARTHER NORTH SO CHANCES ARE A
LITTLE HIGHER. TEMPERATURES WILL STAY WELL BELOW NORMAL BEING UNDER
THE INFLUENCE OF THE ARCTIC SURFACE HIGH...THOUGH SOME GRADUAL
MODERATION SHOULD TAKE PLACE AS THE EARLY MARCH SUN WORKS ON THE
AIR. MORE WIND CHILL ADVISORIES ARE LIKELY...THOUGH...ESPECIALLY
FRIDAY NIGHT INTO SATURDAY MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 605 AM CST MON FEB 24 2014
VFR CONDITIONS WILL CONTINUE TODAY AS COLD...DRY CANADIAN HIGH
PRESSURE REMAINS OVER THE AREA. A SHORTWAVE TROUGH DROPPING ACROSS
THE DAKOTAS TODAY WILL SPREAD INCREASING/LOWERING CLOUDS INTO THE
AREA LATE THIS AFTERNOON BUT CIGS WILL REMAIN AOA 10K FT. THE TROUGH
WILL SLIDE ACROSS THE AREA THIS EVENING. LIFT WITH THIS FEATURE WILL
BE ON THE WEAK SIDE AND THE QUESTION REMAINS WILL THE LIFT BE ENOUGH
TO OVERCOME THE DRIER LOW LEVEL AND PRODUCE SOME -SN AT THE TAF
SITES. MODEL CONSENSUS HAS THE LIFT OVERCOMING THE DRY AIR AT KRST
WITH A PERIOD OF MVFR/IFR CIGS/VSBYS IN -SN AS THE TROUGH MOVES BY.
KLSE REMAINS ON THE EDGE OF WHERE LIFT APPEARS TO BE ENOUGH TO
OVERCOME THE DRY AIR AND ONLY INCLUDED A PERIOD OF P6SM -SN AT KLSE.
MODEL SOUNDINGS SHOWING SOME MOISTURE/SATURATION TO LINGER ACROSS
THE AREA LATER TONIGHT...TRAPPED UNDER AN INVERSION NEAR 925MB.
CARRIED BKN CIGS IN THE 2K-3K RANGE AT THE TAF SITES AFTER THE -SN
MOVES OUT.
&&
.CLIMATE...
ISSUED AT 300 AM CST MON FEB 24 2014
GIVEN ALL THE COLD AIR TO ROUND OUT THE MONTH OF FEBRUARY...HERE IS
HOW FEBRUARY AND THE WINTER OVERALL WOULD STACK UP COMPARED TO
RECORDS BASED ON THE CURRENT FORECAST...
...FOR THE MONTH OF FEBRUARY...
LA CROSSE... 9.3 AVERAGE TEMPERATURE...3RD COLDEST
COLDER FEBRUARYS...
1873... 3.9
1936... 4.3
ROCHESTER... 6.7 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1936... 0.5
1979... 5.7
1917... 6.0
...FOR THE WINTER...DECEMBER THROUGH FEBRUARY...
LA CROSSE... 11.5 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1872-1873... 8.4
1874-1875... 10.5
1977-1978... 11.4
1935-1936... 11.4
ROCHESTER... 8.8 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1978-1979... 5.6
1886-1887... 5.9
1935-1936... 8.1
1977-1978... 8.7
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RRS
CLIMATE......AJ/RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
300 AM CST MON FEB 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CST MON FEB 24 2014
...CURRENTLY AS OF 09Z...
WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING ALONG
THE U.S. WEST COAST NORTHWARD THROUGH ALASKA...WHILE TROUGHING
DOMINATED FROM THE NORTH POLE SOUTHWARD THROUGH MUCH OF CANADA AND
THE NORTHERN TIER OF THE U.S.. WITHIN THIS TROUGHING...THERE ARE 3
IMPORTANT SHORTWAVE TROUGHS OF NOTE FOR THE FORECAST...
1. OVER SOUTHERN SASKATCHEWAN INTO NORTHWEST MONTANA...EXPECTED
TO BRING THE SNOW LATE TODAY INTO TONIGHT. DPVA AND ISENTROPIC
LIFT AHEAD OF THIS SHORTWAVE HAS SUPPORTED LIGHT SNOW ACROSS MUCH
OF MONTANA SOUTHEAST INTO NEBRASKA.
2. ALONG THE NUNAVUT/NORTHWEST TERRITORIES BORDER IN CANADA...
EXPECTED TO BRING THE ARCTIC COLD SHOT TO THE AREA TUESDAY NIGHT.
IN ITS WAKE SURFACE TEMPERATURES RANGE FROM A BITTER 20 TO 30
BELOW ZERO.
3. RIGHT NEAR THE NORTH POLE...SPECIFICALLY 84 N / 130 W...EXPECTED
TO BRING THE ARCTIC AIR FOR THURSDAY INTO THE WEEKEND. IN ITS
WAKE... 925MB TEMPS RANGE FROM -28 TO -34C PER GFS ANALYSIS.
OVER THE FORECAST AREA...SKIES REMAIN CLEAR DUE TO PLENTY OF DRY AIR
AS SEEN ON THE 00Z MPX SOUNDING. SOME CIRRUS IS BEGINNING TO
ENCROACH FROM THE WEST...THOUGH. TEMPERATURES HAVE SLOWLY COOLED
THROUGH THE NIGHT RESULTING FROM A WESTERLY BREEZE...WITH READINGS
IN THE LOWER SINGLE DIGITS.
... FORECAST ...
MODELS ARE IN GOOD AGREEMENT MARCHING THE FIRST SHORTWAVE TROUGH
INTO THE EASTERN DAKOTAS BY 00Z...OVER THE FORECAST AREA BY 06Z AND
INTO LOWER MICHIGAN BY 12Z TUE. 275-280K ISENTROPIC LIFT PROGS
SUGGEST THAT TO GET THE SNOW OVER MONTANA AND NEBRASKA INTO THE
FORECAST AREA...WE HAVE TO WAIT FOR THE SHORTWAVE TROUGH TO ARRIVE.
THIS IS WHY MODELS SLOWED DOWN OVER THE PAST FEW DAYS OF BRINGING
SNOW TO THE AREA. THE BEST LIFT...ALBEIT WEAK...IS PROGGED OVER THE
SOUTHWESTERN HALF OF THE FORECAST AREA BETWEEN 01-06Z...THEN SHIFTS
TO FAR SOUTHWEST WI BETWEEN 06-09Z BEFORE EXITING. PRECIPITATION
CHANCES HAVE BEEN ADJUSTED TO FIT THE TIMING OF THE LIFT SIGNAL.
STILL DOES NOT LOOK LIKE THERE WILL BE MUCH SNOW GIVEN THE WEAK
NATURE OF THE LIFT...PRECIPITABLE WATER ONLY 0.1-0.2 OF AN
INCH...AND THE SNOW RUNNING INTO THE DRY AIRMASS CURRENTLY IN PLACE.
ANY LIFT TOO IS MOSTLY ABOVE THE DENDRITIC GROWTH ZONE. PREVIOUS
FORECAST AMOUNTS OF LESS THAN 1 INCH SEEM REASONABLE.
REGARDING TEMPERATURES. 925MB READINGS AT 18Z TODAY ARE SIMILAR TO
YESTERDAY AT 18Z...BETWEEN -13 AND -16C. ONLY DIFFERENCES BETWEEN
TODAY AND YESTERDAY IS MORE CLOUD COVER AND STARTING OFF COLDER...
WHICH SHOULD KEEP HIGHS A LITTLE COOLER. IN THE WAKE OF THE
SHORTWAVE TROUGH PASSAGE TONIGHT...925MB TEMPS COOL TO -14 TO -19C.
A NORTHWEST BREEZE COMBINED WITH CLOUDS SHOULD HELP TO HOLD LOWS UP
SOMEWHAT...BUT READINGS SHOULD FALL INTO THE SINGLE DIGITS ABOVE AND
BELOW ZERO THROUGH ADVECTION...COLDEST OVER THE NORTHWEST HALF OF
THE FORECAST AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 300 AM CST MON FEB 24 2014
THE BIG IMPACT STORY HERE IS THE COLD...
SHORTWAVE TROUGH CURRENTLY OVER THE NUNAVUT/NORTHWEST TERRITORIES
REGION IS PROGGED TO DROP THROUGH THE FORECAST AREA LATE
TUESDAY...USHERING IN THE FIRST SURGE OF BITTER COLD ARCTIC AIR.
TROUGH SHOULD GO THROUGH PRECIP FREE WITH JUST SOME CLOUDS. 925MB
TEMPS PLUMMET TO -21 TO -24C BY 06Z WEDNESDAY...SENDING SURFACE
TEMPERATURES DOWN BELOW ZERO. WITH THE COLD AIR FIRMLY ENTRENCHED
FOR 06-12Z...TEMPERATURES SHOULD IN MOST LOCATIONS DIP INTO TEENS
BELOW ZERO. MOS GUIDANCE WIND FORECASTS SUGGEST THE TYPICAL COLD
SPOTS COULD DECOUPLE...THUS HAVE THEM APPROACHING 20 BELOW. A WIND
CHILL ADVISORY IS A GIVEN FOR TUESDAY NIGHT INTO WEDNESDAY MORNING.
A BRIEF BREAK IN THE COLD AIR COMES WEDNESDAY AFTERNOON AS WESTERLY
WINDS INCREASE AND PULL IN SOME DOWNSLOPED AIR OFF THE ROCKIES. THIS
INCREASE IS A RESULT OF THE NEXT SHORTWAVE TROUGH NEAR THE NORTH
POLE DROPPING INTO THE MN ARROWHEAD. 925MB WINDS APPROACH 45-50 KT
AT 00Z THURSDAY WEST OF THE MISSISSIPPI RIVER...BRINGING UP CONCERN
OF A POSSIBLE WIND ADVISORY. HOWEVER...A STRONG INVERSION LOOKS TO
DEVELOP TO PRECLUDE MIXING THOSE HIGHER WINDS DOWN. IT STILL WILL BE
BRISK...THOUGH...AND STRONG ENOUGH TO RESULT IN SOME BLOWING AND
DRIFTING OF SNOW IN OPEN AREAS.
NEXT ARCTIC COLD SHOT WHICH IS MUCH MORE IMPRESSIVE COMES IN LATE
WEDNESDAY NIGHT. THE AFOREMENTIONED NORTH POLE SHORTWAVE CROSSES
UPPER MICHIGAN WEDNESDAY NIGHT...DRAGGING AN ARCTIC COLD FRONT
THROUGH THE FORECAST AREA. A STRONG PRESSURE RISE IS PROGGED BEHIND
THIS FRONT WHICH SHOULD RESULT IN A PERIOD OF BRISK NORTHWEST WINDS.
THEN 925MB TEMPS PLUMMET TO -23 TO -27C AT 12Z THURSDAY. DID NOT GO
AS COLD AS THESE WOULD SUGGEST GIVEN THE LATE ARRIVAL OF THE COLD
AIR AND PLENTY OF WIND. STILL...THE WIND CHILLS ARE PLENTY LOW
ENOUGH FOR AN ADVISORY.
THURSDAY AND THURSDAY NIGHT LOOK DOWNRIGHT COLD. 850MB TEMP
ANOMALIES ARE PROGGED BETWEEN 2.5-3 STANDARD DEVIATIONS BELOW
NORMAL...SUGGESTING RECORD TERRITORY. IN ADDITION...HIGH PRESSURE
SETTLES OVERHEAD THURSDAY NIGHT...SETTING UP POTENTIAL FOR
TEMPERATURES TO TANK. ONLY CAVEAT WILL BE SOME INCREASING MID/HIGH
CLOUDS LATER THURSDAY NIGHT. SOME WISCONSIN COLD SPOTS COULD DIP TO
30 BELOW OR COLDER...AS INDICATED BY THE MEX GUIDANCE.
FOR FRIDAY THROUGH MONDAY...THE FORECAST AREA WILL BE IN-BETWEEN
ARCTIC COLD UPPER TROUGHING ENCOMPASSING MUCH OF SOUTHERN CANADA AND
SHORTWAVE TROUGHS TRAVERSING THE SOUTHERN 2/3 OF THE U.S.. AT THE
SAME TIME AT THE SURFACE...ARCTIC HIGH PRESSURE SHOULD BE IN PLACE
FOR MUCH OF THE TIME. ONE SHORTWAVE MAY BRING SOME LIGHT SNOW TO
LOCATIONS SOUTH OF I-90 ON FRIDAY...IF IT CAN MAKE IT THROUGH THE
DRY AIR. ONLY KEPT 20 PERCENT CHANCES IN FOR THIS TIME PERIOD. SAME
HOLDS TRUE FOR ANOTHER SHORTWAVE TROUGH GOING BY SATURDAY NIGHT INTO
SUNDAY...THOUGH THE TRACK IS A BIT FARTHER NORTH SO CHANCES ARE A
LITTLE HIGHER. TEMPERATURES WILL STAY WELL BELOW NORMAL BEING UNDER
THE INFLUENCE OF THE ARCTIC SURFACE HIGH...THOUGH SOME GRADUAL
MODERATION SHOULD TAKE PLACE AS THE EARLY MARCH SUN WORKS ON THE
AIR. MORE WIND CHILL ADVISORIES ARE LIKELY...THOUGH...ESPECIALLY
FRIDAY NIGHT INTO SATURDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1130 PM CST SUN FEB 23 2014
VFR CONDITIONS TO CONTINUE THROUGH MONDAY AS HIGH PRESSURE SINKS
SLOWLY INTO MONTANA WHILE KEEPING THE RIDGE EXTENDING FROM THE
HIGH OVER IOWA INTO ILLINOIS. A SHORT WAVE TROUGH APPROACHING FROM
THE NORTHWEST WILL START TO SPREAD HIGH AND MID LEVEL CLOUDS OVER
THE AREA THROUGH THE AFTERNOON WITH GRADUALLY LOWER CEILINGS. THE
FORCING FROM THE WAVE WILL START TO MOVE IN MONDAY EVENING AND THE
CONCERN BECOMES WHETHER THE FORCING WILL BE STRONG ENOUGH TO
PRODUCE SATURATION OR NOT. THE 24.00Z NAM SUGGEST THE BEST
ISENTROPIC UP GLIDE ON THE 275K SURFACE WILL STAY SOUTH OF THE
AREA WITH AROUND 30 MB NEEDED TO OBTAIN SATURATION. IF THIS
OCCURS...WOULD NOT EXPECT MUCH MORE THAN FLURRIES TO OCCUR. THE
24.00Z GFS ALSO SHOWS THE BEST ISENTROPIC UP GLIDE STAYING SOUTH
BUT IS STRONGER THAN THE NAM FOR WHAT IT DOES BRING ACROSS THE
AREA...BETWEEN 2 AND 3 UBAR/S. THE GFS DOES SATURATE AND WOULD
BRING LIGHT SNOW INTO KRST DURING THE EVENING AND TO KLSE AFTER
25.06Z. THE 23.21Z SREF WOULD SUGGEST THE BEST VISIBILITY REDUCING
SNOW WILL STAY SOUTH WITH THE BETTER FORCING...BUT DOES SHOW
PRETTY DECENT PROBABILITIES OF A VISIBILITY OF 3 MILES OR LESS AT
KRST. HAVE THUS BROUGHT IN MVFR CONDITIONS WITH LIGHT SNOW TO KRST
FOR MONDAY EVENING.
&&
.CLIMATE...
ISSUED AT 300 AM CST MON FEB 24 2014
GIVEN ALL THE COLD AIR TO ROUND OUT THE MONTH OF FEBRUARY...HERE IS
HOW FEBRUARY AND THE WINTER OVERALL WOULD STACK UP COMPARED TO
RECORDS BASED ON THE CURRENT FORECAST...
...FOR THE MONTH OF FEBRUARY...
LA CROSSE... 9.3 AVERAGE TEMPERATURE...3RD COLDEST
COLDER FEBRUARYS...
1873... 3.9
1936... 4.3
ROCHESTER... 6.7 AVERAGE TEMPERATURE...4TH COLDEST
COLDER FEBRUARYS...
1936... 0.5
1979... 5.7
1917... 6.0
...FOR THE WINTER...DECEMBER THROUGH FEBRUARY...
LA CROSSE... 11.5 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1872-1873... 8.4
1874-1875... 10.5
1977-1978... 11.4
1935-1936... 11.4
ROCHESTER... 8.8 AVERAGE TEMPERATURE...5TH COLDEST
COLDER WINTERS...
1978-1979... 5.6
1886-1887... 5.9
1935-1936... 8.1
1977-1978... 8.7
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
CLIMATE...AJ/RRS
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1000 PM MST TUE FEB 25 2014
.UPDATE...
ISSUED AT 803 PM MST TUE FEB 25 2014
SNOTELS IN THE NORTHERN MOUNTAINS INDICATED ACCUMULATIONS HAD
ENDED AT MOST LOCATIONS AND ONLY BUFFALO PARK HAD PICKED UP ANY
MEASURABLE ACCUMULATION IN THE PAST COUPLE OF HOURS. SATELLITE
INDICATED THAT THE TROUGH AXIS HAD EXITED THE ADVISORY AREA.
CONSEQUENTLY...CONFIDENT SHORT RANGE MODELS ARE CORRECT IN
PRODUCING LITTLE TO NO ADDITIONAL SNOWFALL IN THE ELKHEAD AND PARK
RANGES. THEREFORE...WENT AHEAD AND CANCELLED THE WINTER WEATHER
ADVISORY WHICH WAS IN EFFECT FOR THE AREA THROUGH WEDNESDAY
MORNING.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 252 PM MST TUE FEB 25 2014
SHORT TERM FORECAST THROUGH THIS EVENING IS BASED ON RAP MODEL TRENDS
THAT SNOW WILL EXPAND SOUTHWARD OVER ROUTT COUNTY EARLY THIS
AFTERNOON. AS OF 21Z...STEAMBOAT LAKE WEB CAM INDICATE THAT SNOW
HAS REACHED HAHNS PEAK VICINITY...BUT NO MOUNTAIN TOP OBSCURATION
NEAR STEAMBOAT SPRINGS. EXPECT THIS TO CHANGE WITHIN THE NEXT
COUPLE OF HOURS AS LEADING EDGE OF BAROCLINIC ZONE AND DECENT
GRADIENT NORTHWEST FLOW LEADS TO OROGRAPHIC SNOW OVER THE MT
ZIRKEL WILDERNESS AREA AND THE PARK RANGE. RAP MODEL INDICATES
RAIN/SNOW BAND MAY EXTEND AS FAR WEST AS MAYBELL AND MEEKER LATE
THIS AFTERNOON AS THE MOISTURE BAND SLIDES SOUTH AND EAST.
PRIMARY CONCERN IS THAT THE AMPLIFYING UPSTREAM RIDGE AXIS HAS
PINCHED OFF THE PACIFIC MOISTURE STREAM INTO NORTHWEST COLORADO...
THIS IS EVIDENT ON THE SATELLITE IMAGES. NOT SURE WHETHER THE
FORECASTED SNOW AMOUNTS FOR THE PARK RANGE WILL REACH THE UPPER
RANGE OF AROUND 7 INCHES...BUT RAP QPF STILL INDICATE THAT A FEW
INCHES OF SNOW REMAIN POSSIBLE. WITH SNOW OBSERVED AT RIVERTON
AND LANDER IN WEST CENTRAL WYOMING...GIVING CREDENCE THAT THE SNOW
IS ON THE WAY. LESSER AMOUNTS OF SNOW IS ANTICIPATED FOR THE FLAT
TOP MOUNTAINS AND GORE RANGE (VAIL PASS)...DO NOT THINK THAT AN
EXPANSION OF THE WINTER WEATHER ADVISORY IS NECESSARY. MOISTURE
STREAM SLIDES EAST AFTER MIDNIGHT WITH MID LEVEL DRY STABLE AIR
ADVECTING INTO NORTHWEST COLORADO...THIS WILL SHUT DOWN OROGRAPHIC
SNOW FAIRLY QUICKLY LATE TONIGHT.
FOR THE SERN HALF OF THE FORECAST AREA THROUGH TONIGHT...CLEAR AND
DRY WEATHER IS EXPECTED FOR THE NEXT 12 TO 18 HOURS.
WEST COAST RIDGE SHIFTS INLAND ON WEDNESDAY BUT BROAD ISENTROPIC
UPGLIDE WILL RESULT IN AN INCREASE OF MID/HIGH LEVEL CLOUDS FROM
THE SOUTHWEST. NAM AND GFS SHOWING HINTS OF MOUNTAIN TOP SPOTTY
SNOW WEDNESDAY AFTERNOON AND NIGHT. SOMETIMES THIS IS OVERDONE BUT
THE TREND WILL BE FOR INCREASING CLOUDS WITH CIRROSTRATUS EVOLVING
INTO ALTOSTRATUS. WITH THE INCREASED CLOUD COVER...EXPECT
RELATIVELY MILD CONDITIONS WEDNESDAY NIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 252 PM MST TUE FEB 25 2014
THE FORECAST AREA COMES UNDER THE INFLUENCE OF THE SUBTROPICAL JET
THROUGH THE WEEKEND. THIS TYPICALLY BRINGS BETTER MOISTURE BUT
MILDER TEMPERATURES WITH ASSOCIATED STORMS. BREEZY TO WINDY
CONDITIONS ARE EXPECTED IN THE MTNS AND HIGH VALLEYS...INTO THE
LOWER VALLEYS WITH SHOWERS.
THURSDAY...A TRANSIENT RIDGE PASSES IN THE EARLY AFTERNOON WITH
DEEPENING MOISTURE IN SW FLOW. 700MB SPECIFIC HUMIDITIES CLIMB TO
4 G/KG IN THE AFTERNOON. THERE IS SOME MODEL DISAGREEMENT ON
TEMPERATURES AND SNOW LEVELS. A COMPROMISE PUTS THE SNOW LEVELS
AROUND 7500FT/8500FT NORTH/SOUTH. THE DEEPEST MOISTURE IS IN THE
SOUTHERN-CENTRAL MTNS. MARGINAL INSTABILITY PRODUCES AREAS OF
STRONGER SHOWERS AND BRIEFLY LOWER SNOW LEVELS.
THURSDAY NIGHT...THE BEST FORCING OCCURS AS THE SUBTROPICAL JET
PUSHES INTO THE SOUTH THEN LIFTS INTO THE CENTRAL ZONES. SNOW
LEVELS LOWER INTO THE NORTHERN VALLEYS...TO 7500FT SOUTH.
FRIDAY IS A BRIEF BREAK UNDER AS A LOCAL RIDGE IS AMPLIFIED AHEAD
OF THE NEXT STRONG STORM BRINGING WARM ADVECTION. MOISTURE REMAINS
AT 4 G/KG SO SHOWERS INCREASE INTO THE AFTERNOON.
FRIDAY NIGHT-SATURDAY NIGHT...THE NEXT SUBTROPICAL JET STREAK LIFTS
THE EASTERN UTAH FRIDAY NIGHT THEN ACROSS WESTERN COLORADO ON
SATURDAY. AGAIN THERE IS A CONVECTIVE COMPONENT FRIDAY NIGHT INTO
SATURDAY. THERE IS AGAIN A CONVECTIVE COMPONENT TO THIS STORM.
SNOWFALL WILL FAVOR THE SOUTHERN AND CENTRAL MTNS. SNOW LEVELS
AROUND 7000FT. SATURDAY NIGHT IS TROUGH PASSAGE WITH NW FLOW
DEVELOPING. SNOW LEVEL DROPS TO AROUND 5000FT BUT WILL FAVOR THE
NW-FACING SLOPES OF THE COLORADO MTNS.
SUNDAY-TUESDAY...ARE NOW A FLAT ZONAL FLOW WITH THE POLAR FRONT
JET SETTLING INTO WYOMING THEN RAKING THE NORTH ON MONDAY. EXPECT
COOLER TEMPERATURES THROUGH THESE PERIODS WITH THE BEST SNOWFALL
FAVORING THE NORTHERN MTNS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 958 PM MST TUE FEB 25 2014
VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH 06Z THU...BUT
LOW CLOUDS MAY BE PROBLEM FOR THE ERN UINTA MOUNTAINS AND NRN CO
MOUNTAINS INCLUDING KHDN/KSBS THROUGH MID-MORNING.
AN UPPER DISTURBANCE CROSSING NE CO PUSHED A COLD FRONT ACROSS NW CO
TO ABOUT THE I-70 CORRIDOR BEFORE CURVING BACK ACROSS NE UT. FRONT
SHOULD STALL OVERNIGHT. A BAND OF LOW-MID LEVEL CLOUDS EXTENDED FROM
THE CENTRAL DIVIDE AREA BACK ACROSS NW CO AND SW WY AND SHOULD
PERSIST UNTIL 12Z-15Z WED WITH MOUNTAIN TOPS OCCASIONALLY OBSCURED
IN CLOUDS/-SN FROM KASE/VAIL PASS NORTHWARD TO K3MW.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...NL
SHORT TERM...PF
LONG TERM...JOE
AVIATION...JAD
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
411 AM EST Wed Feb 26 2014
.Near Term [Through Today]...
At 09z, a surface cold front extended from a weak low in SC,
southwest to near Albany GA, to near Destin FL, and then along much
of the rest of the LA-TX Gulf coast. Regional radars showed a fairly
large area of rain along and to the north of the surface cold front
from near the AL-GA state line westward to SE TX. The placement of
the rain relative to the surface front was suggestive of an anafront
structure, with rearward sloping ascent along the cold front through
the vertical. This is confirmed by WSW flow on area radar VWPs in
the 900-700mb layer, and from a glance at RAP isentropic charts.
Given the isentropic ascent in the lowest levels of the troposphere,
but a general lack of significant forcing aloft, it`s likely that
rain will continue to be forced in a shallow layer just above the
surface through the remainder of the day. Models are in fairly good
agreement on the timing of the best isentropic ascent and QPF. We
leaned towards the consensus of recent local and NCEP WRF runs. With
widespread rain expected, PoPs were raised to 100% for today pretty
much everywhere across the forecast area. The rain should be most
widespread (and heaviest) in the morning, with it tapering off and
clearing from NW-SE in the afternoon and early evening.
Looking at GOES blended precipitable water product, there is a large
plume of PWATS >150% of normal extending from the western parts of
our forecast area west into Texas. This deeper moisture will
continue to advect into the area today, and could support some
locally heavier rain. This will be especially true near the Gulf
coast - closer to the surface cold front as the strongest forcing
for ascent arrives this morning after sunrise. Maximum QPF from
convection allowing models (CAM) is focused around Gulf and Franklin
counties and is on the order of 2-3 inches. With the heaviest rain
likely to fall in the lower portions of river basins, and average
rainfall generally between 0.50 and 1.00 inches, we don`t anticipate
any significant flooding issues. Instability should be limited
enough to only support some general thunderstorms - updrafts should
be too weak to pose much of a severe weather concern.
.Short Term [Tonight Through Friday]...
Rain will taper off from north to south this evening, but may not
clear completely from our Southeast FL Big Bend zones until Thursday
morning. As skies clear behind the rain, temps will tumble into the
30s except for coastal and southeastern sections of the Big Bend. A
light freeze is forecast along and north of an Albany to Dothan to
Crestview line. Maximum freeze durations in Coffee County AL will be
about 5 hours. Max temps will be about 10 degrees below normal on
Thursday and range from the mid 50s far northwest to Around 60
southeast. This will set the stage for a widespread light freeze
Thursday night that will impact most inland areas. Coastal locations
will hold at 40. Temps will moderate to within a few degrees of
normal on Friday with max temps ranging from the lower 60s north to
the mid to upper 60s southeast.
.Long Term [Friday Night Through Wednesday]...
On Friday NIGHT, a shortwave will be moving across the Mid
Atlantic states. Further to the west, a disturbance will be moving
onshore into central California. A vort max located over the Rockies
will propagate eastward in zonal flow bringing slight PoP chances
on Saturday, however this forcing appears to be weak and displaced
more to the north of our CWA. From here on the GFS and Euro really
diverge in their handling of the upcoming pattern. The GFS is more
aggressive in phasing a shortwave over western Mexico with a
shortwave rounding the base of a trough over Idaho. This combination
pushes a surface front through our area late Monday night into
Tuesday but quickly exits the area. The Euro meanwhile remains
less amplified keeping the flow aloft more zonal and bringing a
series of vort maxes through the area early next week. This will
cause a stalling of a surface front over our CWA, and with each
passing upper-level vort max another round of rain. Both agree
that Tuesday morning should be pretty wet but given the
uncertainty with which this front will exit we have tentatively
gone with 40 PoPs for Tuesday afternoon.
&&
.Aviation...
[Through 06Z Thursday] Rain will quickly spread into the area in the
early morning hours - affecting all terminals. -RA should first
arrive at DHN/ECP around 09z, eventually reaching VLD around 12z. We
expect IFR CIGS to develop at all terminals prior to 14z, except ABY
where low end MVFR CIGS are expected. Some +RA with TS will be
possible closer to the Gulf coast, particularly at ECP and TLH. Some
of the +RA could reduce visibilities to around 1-3SM at times. Rain
will gradually clear out in the afternoon from NW-SE, with CIGS
gradually lifting through MVFR to VFR range by the evening.
&&
.Marine...
A cold front will slip south across the waters today shifting winds
to offshore. Wind speeds behind the front will reach marginal small
craft advisory criteria across the western legs by midday. Advisory
conditions will be possible across the eastern zones tonight. Winds
will then drop below cautionary levels by midday Thursday as high
pressure builds toward the waters. Winds will remain below headline
criteria through the weekend as they gradually veer to the east and
then southeast.
&&
.Fire Weather...
Widespread wetting rains are expected today, which will leave fuel
moisture rather high on Thursday. Some of the finer (smaller) fuels
(measured by 10-hr fuel moisture) could dry out as a much drier air
mass arrives for Thursday, but should not be sufficiently dry in
Florida or Georgia to create red flag conditions. In southeast
Alabama, red flag criteria includes 4+ hr durations of RH < 25%.
This looks achievable, but the wet fuels would likely preclude any
sort of critical fire weather conditions. For now, we will maintain
the Fire Weather Watch. It`s possible durations could be met again
on Friday in southeast Alabama, and by then smaller fuels would have
likely dried more substantially.
&&
.Hydrology...
Periods of moderate rain today and tonight across the forecast
area will result in slight to modest rises on area rivers. The
Choctawhatchee River at Bruce is forecast to crest right at flood
stage from Thursday into Saturday. The Apalachicola River at
Blountstown is at its crest and is forecast to fall below flood
stage Thursday evening. The Aucilla River at Lamont is forecast to
reach flood stage Thursday night and crest Friday night. Storm
total rainfall through Thursday morning is forecast to be less
than an inch north of I-10 with a maximum of near two inches over
coastal sections of Gulf and Franklin Counties. With the greatest
totals falling in the lower stretches of the river basins, rises
will be confined mainly to FL.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 60 39 60 29 65 / 100 50 10 0 0
Panama City 60 39 58 36 62 / 100 50 10 0 0
Dothan 54 31 57 31 62 / 100 30 0 0 0
Albany 54 32 58 29 62 / 100 20 0 0 0
Valdosta 58 37 59 30 64 / 100 50 0 0 0
Cross City 65 44 61 30 67 / 100 60 20 0 0
Apalachicola 64 41 58 35 61 / 100 60 10 0 0
&&
.TAE Watches/Warnings/Advisories...
FL...None.
GA...None.
AL...Fire Weather Watch from Thursday morning through Thursday
afternoon for Coffee-Dale-Geneva-Henry-Houston.
GM...Small Craft Advisory from 11 AM this morning to 10 AM EST
Thursday for Coastal waters from Apalachicola to Destin FL
out 20 NM-Waters from Apalachicola to Destin FL from 20 to
60 NM.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...WOOL
LONG TERM...
AVIATION...LAMERS
MARINE...WOOL
FIRE WEATHER...LAMERS
HYDROLOGY...BARRY/WOOL
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
236 AM EST WED FEB 26 2014
.SYNOPSIS...
A FRONT AND UPPER ENERGY WILL PROVIDE A CHANCE OF RAIN TODAY...THEN
FAIR...DRIER AND COOLER WEATHER EXPECTED THROUGH LATE WEEK. AN UPPER
DISTURBANCE WILL BRING A CHANCE OF SHOWERS FRIDAY NIGHT AND
SATURDAY. THE NEXT FRONT WILL AFFECT OUR REGION EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
SURFACE FRONT GENERALLY STRETCHED ACROSS THE CENTRAL FORECAST
AREA...STRETCHING WESTWARD INTO THE LOWER MISS VALLEY. THIS ALONG
WITH A SERIES OF SOUTHERN STREAM UPPER IMPULSES...AHEAD OF A
NORTHERN STREAM UPPER IMPULSE THAT WILL DIVE FROM THE CENTRAL PLAINS
INTO THE SE US TODAY...WILL PROMOTE SOME RAIN. LATEST HIGH
RESOLUTION MODELS INDICATE RAIN AREA TO OUR WEST WILL SHIFT
EAST...REACHING THE CSRA BEFORE DAYBREAK AND SPREADING EAST ACROSS
MOST OF THE FA THIS MORNING...MOVING OUT OF THE FA DURING THE
AFTERNOON. SLIGHT CHANCE THAT A LITTLE MELTING SNOW COULD MIX
WITH RAIN ACROSS THE NORTHERN FA...BUT CHANCES OF THAT APPEAR TOO
LOW TO INCLUDE IN THE FORECAST...PLUS ANY SNOW WOULD MELT ON
IMPACT WITH NO ACCUM.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
EXPECT CLEARING SKIES BY EARLY EVENING. A SECONDARY DRY FRONT WILL
MOVE SOUTH THROUGH THE REGION TONIGHT...FOLLOWED BY ANOTHER DRY
FRONT ROLLING THROUGH THURSDAY NIGHT...MAINTAINING A CONTINUED
INFLUX OF COOLER AND DRIER AIR. HIGH PRESSURE CENTER WILL BUILD IN
FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A WEAK SHORTWAVE TROUGH WILL BRING A CHANCE OF PRECIPITATION FRIDAY
NIGHT INTO EARLY SATURDAY. SHORTWAVE TROUGH WILL SHIFT EAST SATURDAY
MORNING AS AN UPPER RIDGE BUILDS OVER THE SOUTHEAST CONUS THROUGH
SUNDAY WITH DRY WEATHER EXPECTED. THE UPPER RIDGE WILL SHIFT EAST
MONDAY AS A TROUGH BUILDS OVER THE WESTERN CONUS. SOME MODEL
DIFFERNCES CONTINUE...BUT ECMWF AND GFS GENERALLY SUGGEST NEXT FRONT
WITH AVAILABLE ATMOSPHERIC MOISTURE TO AFFECT OUR REGION IN THE
MONDAY/TUESDAY TIME FRAME. GENERALLY BLENDED LATEST GUIDANCE WITH
ONGOING FORECAST.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. HOWEVER...MODEL
INCONSISTENCIES LOWER THE CONFIDENCE AND THERE IS THE POSSIBILITY OF
A PERIOD OF MVFR CONDITIONS WEDNESDAY MORNING.
A COLD FRONT WILL SINK SOUTHWARD AND THROUGH THE AREA OVERNIGHT.
NORTHERLY WINDS WILL DEVELOP BEHIND THE FRONT DURING THE EARLY
MORNING HOURS. EXPECT AN INCREASE IN CLOUDINESS AND THE DEVELOPMENT
OF RAIN OVER MOST OF THE AREA DURING THE EARLY MORNING HOURS MAINLY
ASSOCIATED WITH A COUPLED H25 JET PATTERN. THE LATEST HRRR SHOWED
COVERAGE UPSTREAM INCREASING AND MOVING INTO THE FORECAST AREA
AROUND 10-12Z. 88D REGIONAL COMPOSITE ALREADY SHOWS SOME AREAS OF
LIGHT RAIN AS FAR EAST AT ALABAMA. CONFIDENCE IS LOW WITH THE
CEILING AND VISIBILITY FORECAST BECAUSE OF MODEL INCONSISTENCY. THE
NAM MOS INDICATED MVFR OR IFR CEILINGS. THE GFS MOS AND LAMP PLUS
SREF GUIDANCE INDICATED CONTINUED VFR CEILINGS AND VISIBILITIES. THE
22Z HRRR INDICATED MAINLY VFR CONDITIONS THROUGH 13Z. LEANED TOWARD
THE MORE OPTIMISTIC GUIDANCE BECAUSE OF THE H85 WESTERLY FLOW AND
THE INITIAL DRYNESS. ALSO...LOOKING BACK AT UPSTREAM OBS THEY ARE
MAINLY IN THE VFR CATEGORY. ALSO...A LACK OF SIGNIFICANT ISENTROPIC
LIFT SHOULD HELP KEEP RAIN MAINLY LIGHT AND LIMIT ITS RESTRICTION TO
VISIBILITY. THE NAM AND GFS SHOW UPPER-LEVEL LIFT SHIFTING EAST OF
THE AREA BETWEEN 16 AND 18Z. RAIN AND LINGERING LOWER CLOUDINESS
SHOULD DIMINISH DURING THIS TIME. AFTER 18Z...CLOUDINESS WILL
GRADUALLY BECOME BROKEN THEN SCATTERED BY 00Z. AFTER 00Z...WINDS
WILL BE GENERALLY REMAIN LIGHT WITH SOME SCATTERED HIGH CLOUDS.
EXTENDED AVIATION OUTLOOK...WITH HIGH PRESSURE OVER THE AREA THROUGH
THE REMAINDER OF THE WEEK...NOT SIGNIFICANT IMPACTS EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1242 AM EST WED FEB 26 2014
.SYNOPSIS...
A GULF COAST LOW PRESSURE SYSTEM WILL MOVE EAST THROUGH GEORGIA
AND FLORIDA TONIGHT INTO WEDNESDAY BRINGING A CHANCE OF RAIN TO
OUR AREA. DRY AND COOLER WEATHER IS EXPECTED THURSDAY AND FRIDAY
WITH ANOTHER CHANCE OF RAIN EARLY SATURDAY WITH A FAST MOVING
SYSTEM.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
UPDATE...FORECAST REMAINS ON TRACK AS FRONT APPROACHES FROM THE
WEST. HAVE ADJUSTED POPS AND CLOUDS TO BETTER REPRESENT CURRENT
OBSERVATIONS WITH INCREASING CLOUDS AND CHANCES OF RAIN OVER THE
NEXT SEVERAL HOURS. BEST CHANCES OF RAIN WILL BE OVER THE SOUTHERN
MIDLANDS AND CSRA OVERNIGHT WITH RAIN SPREADING INTO THE CENTRAL
MIDLANDS DURING THE EARLY MORNING HOURS. RAINFALL AMOUNTS THROUGH
DAYBREAK ARE EXPECTED TO BE TWO TENTHS OF AN INCH OR LESS.
TEMPERATURES REMAIN ON TRACK FOR LOWER 40S FOR THE NORTHERN AND
WESTERN MIDLANDS WITH MID 40S TO AROUND 50 ELSEWHERE.
PREVIOUS DISCUSSION...CHANCES OF RAIN INCREASE LATE TONIGHT AS
BROAD UPPER TROUGH SINKS ACROSS THE GREAT LAKES AND OHIO VALLEY
REGION DRIVING A COLD FRONT THROUGH THE FORECAST AREA EARLY
WEDNESDAY MORNING BEFORE HIGH PRESSURE BUILDS IN AT THE SURFACE
BEHIND THE FRONT WEDNESDAY AFTERNOON. WESTERLY LOW LEVEL FLOW
AHEAD OF THE SHORTWAVE AND FRONT IS FORECAST TO BACK MORE
SOUTHWESTERLY THIS EVENING ALLOWING FOR ATMOSPHERIC MOISTURE TO
INCREASE WITH FLOW OFF THE WESTERN GULF OF MEXICO. HOWEVER...THE
TIME FRAME FOR SIGNIFICANT MOISTURE TO MOVE INTO THE REGION BEFORE
THE FRONT ARRIVES IS SHORT AND A LIMITING FACTOR DESPITE MODERATE
UPPER DYNAMICS ARRIVING AROUND THE 12Z TIME FRAME AS THE NORTHERN
AND SOUTHERN STREAM JETS COUPLE TO PROVIDE STRONG OMEGA AND UPWARD
VERTICAL MOTION OVER THE FORECAST AREA.
HAVE INCREASED POPS SLIGHTLY FROM PREVIOUS FORECAST...HIGHEST POPS
FROM THE CSRA ACROSS THE SOUTHEAST MIDLANDS LATE TONIGHT INTO
WEDNESDAY MORNING WITH A GRADIENT TO LOWER POPS TO THE NORTHWEST
WHERE MOISTURE WILL NOT BE AS GREAT. STILL FIGURE THE BEST TIME
FRAME FOR HIGHEST POPS WILL BE FROM 09Z-15Z WITH CHANCES OF RAIN
DECREASING FROM NORTHWEST TO SOUTHEAST THROUGH THE DAY WEDNESDAY.
LATEST 12Z NAM SOUNDINGS SUGGEST A MIX OF SNOW/RAIN POSSIBLE
ACROSS THE NORTHERN MIDLANDS WEDNESDAY MORNING WITH DEEP MOISTURE
INTO SNOW GROWTH ZONE AND NEAR SURFACE TEMPERATURES LIKELY IN THE
30S. CONFIDENCE IS LOW HOWEVER WITH LITTLE SUPPORT FROM
GFS...I.E. NO MOISTURE IN SNOW GROWTH ZONE. STILL THINK HIGHER
POPS WILL BE SOUTH OF THE NORTHERN MIDLANDS...BUT WILL INCLUDE
CHANCE SNOW/RAIN SHOWERS ACROSS NORTHERN LANCASTER COUNTY WHERE
PARTIAL THICKNESS SCHEMES FAVOR MIX.
CLOUDINESS LATE TONIGHT SHOULD KEEP TEMPERATURES FROM FALLING
SOMEWHAT...FAVOR WARMER MAV GUIDANCE. TEMPERATURES WILL BE MUCH
COOLER WEDNESDAY COMPARED TO TODAY WITH COLD ADVECTION TAKING
PLACE DURING THE DAY DESPITE SOME CLEARING SKIES BY AFTERNOON.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
WEDNESDAY NIGHT...THE LOW PRESSURE SYSTEM AND ALL ASSOCIATED
PRECIPITATION WILL BE WELL OFFSHORE BY WEDNESDAY NIGHT. COLD AIR
ADVECTION AND DECENT RADIATIONAL COOLING CONDITIONS WILL LEAD TO
BELOW NORMAL OVERNIGHT LOW TEMPERATURES...IN THE UPPER 20S NORTH
TO LOWER 30S SOUTH.
THURSDAY THROUGH THURSDAY NIGHT...A BROAD UPPER TROUGH WILL MOVE
OVER THE EASTERN CONUS ON THURSDAY PROMOTING WEST-NORTHWESTERLY
FLOW ALOFT. AT THE SURFACE...LOW PRESSURE OVER THE GREAT LAKES
REGION WILL BRING A DRY COLD FRONT THROUGH THE AREA. TEMPERATURES
WILL MAX OUT IN THE MID 50S TO NEAR 60 UNDER SUNNY SKIES. SURFACE
HIGH PRESSURE WILL SHIFT INTO THE OHIO VALLEY THURSDAY NIGHT
ALLOWING SURFACE WINDS TO ROTATE FROM WESTERLY TO NORTHEASTERLY.
MOSTLY CLEAR SKIES OVERNIGHT WILL SET THE STAGE FOR ANOTHER CHILLY
NIGHT WITH LOWS IN THE UPPER 20S TO NEAR 30.
FRIDAY THROUGH FRIDAY NIGHT...THE UPPER TROUGH WILL BE OFF THE
COAST BY FRIDAY WITH UPPER FLOW BECOMING ZONAL. SURFACE HIGH
PRESSURE WILL SHIFT OVER THE MID-ATLANTIC AND WEDGE INTO THE
FORECAST AREA FOR FRIDAY. TEMPERATURES WILL MAX OUT IN THE UPPER
40S NORTH TO MID 50S SOUTH. A WEAK SHORTWAVE TROUGH WILL BRING A
CHANCE OF PRECIPITATION FRIDAY NIGHT INTO EARLY SATURDAY. MOSTLY
CLOUDY SKIES OVERNIGHT WITH LOW TEMPERATURES ABOVE FREEZING IN THE
LOWER 30S TO NEAR 40.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
SHORTWAVE TROUGH WILL SHIFT EAST SATURDAY MORNING AS AN UPPER
RIDGE BUILDS OVER THE SOUTHEAST CONUS THROUGH SUNDAY WITH DRY
WEATHER EXPECTED. THE UPPER RIDGE WILL SHIFT EAST MONDAY AS A
TROUGH BUILDS OVER THE WESTERN CONUS. SIGNIFICANT TIMING
DIFFERENCES BETWEEN THE ECMWF AND GFS WITH THE NEXT SYSTEM
ARRIVING DURING THE MONDAY/TUESDAY TIME FRAME. THE ECMWF IS
A BIT QUICKER BRINGING THE SYSTEM THROUGH THAN THE GFS. BELOW
NORMAL MAX TEMPERATURES ON SATURDAY BUT OTHERWISE NEAR NORMAL
HIGHS IN THE 60S FOR THE REST OF THE EXTENDED. LATEST GUIDANCE HAS
CONTINUED TO TREND UP WITH TEMPERATURES FOR SUNDAY AND MONDAY.
&&
.AVIATION /06Z WEDNESDAY THROUGH MONDAY/...
EXPECT MAINLY VFR CONDITIONS DURING THE TAF PERIOD. HOWEVER...MODEL
INCONSISTENCIES LOWER THE CONFIDENCE AND THERE IS THE POSSIBILITY OF
A PERIOD OF MVFR CONDITIONS WEDNESDAY MORNING.
A COLD FRONT WILL SINK SOUTHWARD AND THROUGH THE AREA OVERNIGHT.
NORTHERLY WINDS WILL DEVELOP BEHIND THE FRONT DURING THE EARLY
MORNING HOURS. EXPECT AN INCREASE IN CLOUDINESS AND THE DEVELOPMENT
OF RAIN OVER MOST OF THE AREA DURING THE EARLY MORNING HOURS MAINLY
ASSOCIATED WITH A COUPLED H25 JET PATTERN. THE LATEST HRRR SHOWED
COVERAGE UPSTREAM INCREASING AND MOVING INTO THE FORECAST AREA
AROUND 10-12Z. 88D REGIONAL COMPOSITE ALREADY SHOWS SOME AREAS OF
LIGHT RAIN AS FAR EAST AT ALABAMA. CONFIDENCE IS LOW WITH THE
CEILING AND VISIBILITY FORECAST BECAUSE OF MODEL INCONSISTENCY. THE
NAM MOS INDICATED MVFR OR IFR CEILINGS. THE GFS MOS AND LAMP PLUS
SREF GUIDANCE INDICATED CONTINUED VFR CEILINGS AND VISIBILITIES. THE
22Z HRRR INDICATED MAINLY VFR CONDITIONS THROUGH 13Z. LEANED TOWARD
THE MORE OPTIMISTIC GUIDANCE BECAUSE OF THE H85 WESTERLY FLOW AND
THE INITIAL DRYNESS. ALSO...LOOKING BACK AT UPSTREAM OBS THEY ARE
MAINLY IN THE VFR CATEGORY. ALSO...A LACK OF SIGNIFICANT ISENTROPIC
LIFT SHOULD HELP KEEP RAIN MAINLY LIGHT AND LIMIT ITS RESTRICTION TO
VISIBILITY. THE NAM AND GFS SHOW UPPER-LEVEL LIFT SHIFTING EAST OF
THE AREA BETWEEN 16 AND 18Z. RAIN AND LINGERING LOWER CLOUDINESS
SHOULD DIMINISH DURING THIS TIME. AFTER 18Z...CLOUDINESS WILL
GRADUALLY BECOME BROKEN THEN SCATTERED BY 00Z. AFTER 00Z...WINDS
WILL BE GENERALLY REMAIN LIGHT WITH SOME SCATTERED HIGH CLOUDS.
EXTENDED AVIATION OUTLOOK...WITH HIGH PRESSURE OVER THE AREA THROUGH
THE REMAINDER OF THE WEEK...NOT SIGNIFICANT IMPACTS EXPECTED.
&&
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1055 PM MST TUE FEB 25 2014
.UPDATE...
ISSUED AT 1048 PM MST TUE FEB 25 2014
SNOW IS MOVING SOUTH AND DECREASING IN IN COVERAGE AND INTENSITY.
DRAMATIC CLEARING IS OCCURRING BEHIND THE SNOW BAND. SO LOWERED
MINS MORE.
UPDATE ISSUED AT 811 PM MST TUE FEB 25 2014
JUST COMPLETED ANOTHER UPDATE. BAND OF SNOW IS HOLDING TOGETHER
VERY WELL DESPITE WHAT EARLIER MODEL OUTPUT SAID. STRONG MID LEVEL
FRONTOGENESIS AND UPPER LEVEL DEFORMATION IS WORKING ITS WAY
ACROSS. SNOW IS LIGHT PROBABLY DUE TO THE VERY POOR THETA-E LAPSE
RATES BUT STILL IT IS GOING TO SNOW. SO RAISED POPS TO 100 PERCENT
FOR THE REST OF THE EVENING AS THIS BAND WORKS ITS WAY SOUTH. WITH
THE SLOWER PROGRESSION OF THE BAND AND LINGERING DYNAMICS...HAVE
KEPT THE POPS GOING FOR A FEW HOURS AFTER 06Z. OTHERWISE MADE
SLIGHT ADJUSTMENTS IN THE TEMPERATURES.
UPDATE ISSUED AT 604 PM MST TUE FEB 25 2014
NICE BAND OF SNOW STILL OVER THE FAR NORTH AT THIS TIME WITH A
SLOW SHIFT SOUTH. SOME UNCERTAINTY HOW FAR SOUTH THIS BAND WILL
GET AND HOW FAST IT WILL DO IT. MESOSCALE GUIDANCE IS INDICATING
THAT THIS BAND WILL THIN AND WEAKEN AS IT MOVES SOUTH. DO HAVE A
RIGHT REAR QUADRANT OF JET AND STRONG PV ANOMALY MOVING IN FROM
THE NORTHWEST. SO AM THINKING THE BAND WILL HOLD TOGETHER.
SO UPPED UP POPS TO DEFINITE IN THE NORTH AND INCREASED THE
REMAINING PORTION OF THE AREA SLIGHTLY. ALSO MADE A SLIGHT
ADJUSTMENT TO THE WINDS BASED ON THE HRRR. LOOKS LIKE THERE WILL
BE A QUICK AND DRAMATIC CLEARING TREND AFTER THE SNOW ENDS. WINDS
WILL BE LIGHT FOR A LITTLE WHILE BEFORE PICKING UP LATER IN THE
NIGHT. AM THINKING THAT WE HAVE THE POTENTIAL TO BE MUCH COLDER
THAN CURRENTLY INDICATED. SO DID MAKE A SLIGHT ADJUSTMENT COLDER
FOR THE NIGHT AND WILL CONTINUE TO WATCH THE TRENDS CLOSELY AND
SEE WHAT THE NEWER GUIDANCE WILL TELL ME.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 113 PM MST TUE FEB 25 2014
MAIN FOCUS IN THE SHORT TERM WAS TEMPERATURES TODAY THROUGH
TOMORROW AND PRECIPITATION THIS AFTERNOON AND OVERNIGHT. HIGH
TEMPERATURES THIS AFTERNOON WERE ADJUSTED SINCE SOME LOCATIONS
REACHED THEIR HIGHS AROUND 18/19Z. AFTER 18Z COLDER AIR MOVED INTO
NORTHERN LOCATIONS WHERE TEMPERATURES HAVE REMAINED FAIRLY
STAGNANT OR INCREASED BY A DEGREE OR TWO. PORTIONS OF NORTHWEST
KANSAS AND EASTERN COLORADO ALONG AND SOUTH OF I-70 HAVE SEEN
TEMPERATURES IN THE UPPER TEENS TO MID 20S...BUT THIS APPEARS TO
BE THE PEAK OF TODAY`S HIGH TEMPERATURES AS THE COLDER AIR BEGINS
TO MOVE IN. SNOW HAS DEVELOPED OVER SOUTHWEST NEBRASKA AND IS
MOVING INTO NORTHWEST KANSAS ASSOCIATED WITH A FAIRLY STRONG AREA
OF FRONTOGENESIS. AS THE SHORTWAVE TROUGH IN MONTANA CONTINUES TO
PUSH SOUTHEAST AND THE STRONG AREA OF FRONTOGENESIS MOVES
SOUTHEAST AND THEN SOUTH...SNOWFALL WILL CONTINUE THROUGH THE
EVENING OVER MOST OF THE TRI-STATE REGION. THIS WILL BE A QUICK
MOVING WAVE AND THE GFS...NAM...AND RAP ALL SHOW PRECIPITATION OUT
OF THE FORECAST AREA BY 06Z. SINCE THE SYSTEM MOVES QUICKLY...SNOW
ACCUMULATIONS WILL ONLY BE AROUND HALF AN INCH SOUTH AND EAST TO 2
INCHES NORTH AND NORTHWEST. CLOUD COVER WILL STICK AROUND A LITTLE
AFTER 06Z...WITH MOST OF THE CWA BEING CLEAR BY 15Z. LOWS TONIGHT
WILL DROP DOWN INTO THE SINGLE DIGITS AS HIGH PRESSURE SETTLES
INTO THE CWA. NORTHERN AREAS WILL SEE LOWS AROUND 1 DEGREE ABOVE
ZERO TO NEAR ZERO WHILE AREAS FURTHER SOUTH AND WEST WILL SEE LOWS
AROUND 5 TO 10 ABOVE ZERO.
AS SURFACE HIGH PRESSURE SLIDES EAST-SOUTHEAST...ANOTHER SHORTWAVE
TROUGH WILL MOVE THROUGH. NO PRECIPITATION IS EXPECTED WITH THE
NEXT TROUGH SINCE DRIER AIR MOVES IN SO HAVE KEPT THE FORECAST DRY
FOR TOMORROW. TEMPERATURES WILL BE DIVIDED WITH HIGHS OVER THE
NORTHERN HALF OF THE TRI-STATE REGION IN THE UPPER 30S TO NEAR 40
AND THE SOUTHERN HALF/SOUTH-SOUTHWEST PORTION OF THE TRI-STATE
REGION IN THE LOW TO MID 40S. MODELS MAY HAVE BEEN PICKING UP ON
THE SNOW COVER IN THE NORTHERN AREA OF THE CWA WHICH IS WHY THE
TEMPERATURES THERE ARE A BIT LOWER. USED A COMBINATION OF CONSALL
AND SREF FOR TOMORROW`S TEMPERATURES TO TREND THEM DOWNWARD IN THE
SOUTHERN PORTIONS OF THE CWA SINCE THEY SEEMED TO BE TOO HIGH TO
ACCOUNT FOR ANY SNOWFALL THOSE AREAS MIGHT RECEIVE TONIGHT. WEST
TO SOUTHWEST WINDS TOMORROW COULD ALSO BECOME BREEZY AROUND 18Z AS
THE SHORTWAVE TROUGH PASSES THROUGH AND DAYTIME MIXING
INCREASES...BUT ONLY HAVE SUSTAINED WINDS AROUND 10 TO 20 MPH
WITH GUSTS AROUND 25 TO 30 MPH.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 224 AM MST TUE FEB 25 2014
WEDNESDAY NIGHT-THURSDAY...PROGRESSIVE SHORTWAVE RIDGE SHOULD HELP
KEEP DRY CONDITIONS IN PLACE THROUGH THESE PERIODS...WITH A SLIGHT
MODERATION OF THE AIR MASS OVER OUR CWA AS STATIONARY FRONT ALONG
FRONT RANGE LIFTS EAST WITH LEE TROUGH DEVELOPMENT. HIGH TEMPS
THURSDAY SHOULD BE NEAR NORMAL FOR WESTERN LOCATIONS (MID 40S TO
NEAR 50F)...WITH COOLER TEMPS IN THE MID/UPPER 30S FURTHER
NORTHEAST.
THURSDAY NIGHT-FRIDAY...NEXT IN A SERIES OF QUICK MOVING SHORTWAVE
TROUGHS WILL MOVE ACROSS THE REGION WITH ARCTIC AIR MASS DROPPING
BACK OVER WESTERN KS. BEST CHANCE FOR MEASURABLE SNOW APPEARS TO BE
LATE THURSDAY NIGHT THROUGH FRIDAY MORNING...WHEN MODELS ARE
ADVERTISING BETTER LARGE SCALE ASCENT. TIMING OF COLD FRONT IS A
LITTLE SLOWER WITH MAIN CAA FRIDAY AFTERNOON...WHICH MAY RESULT IN
QUITE A GRADIENT FROM THE NORTH-SOUTH OVER OUR CWA (LIKELY FALLING
TEMPS ACROSS THE NORTH).
FRIDAY NIGHT-TUESDAY...DESPITE DIFFERENCES IN THE LARGE SALE PATTERN
THROUGH THE EXTENDED PERIODS...MODELS HAVE COME INTO BETTER
AGREEMENT ON STUBBORN ARCTIC AIR MASS REMAINING IN PLACE OVER OUR
CWA...WITH ECMWF NOW TRENDING EVEN COLDER THAN THE LAST 3 RUNS OF
THE GFS. REGARDING LARGE SCALE PATTERN...ECMWF SHOWS MORE OF A
QUASI-ZONAL PATTERN WITH LOWER HEIGHTS SHIFTED SOUTH...WHILE GFS
SHOWS MORE OF A SPLIT FLOW PATTERN WITH THE NORTHERN STREAM HOLDING
MORE INFLUENCE OVER OUR CWA. EITHER SOLUTION FAVORS REINFORCING SHOTS
OF COLD ARCTIC AND AND PROLONGED BELOW NORMAL TEMPERATURES THROUGH AT
LEAST EARLY NEXT WEEK...ALONG WITH A SERIES OF QUICK MOVING
SHORTWAVES PASSING THROUGH THE REGION.
I TRENDED HIGH/LOW TEMPS DOWN TO ACCOUNT FOR THE COLDER PATTERN
CURRENT MODEL RUNS ARE ZEROING IN ON. EXPECTED CLOUD COVER
COMPLICATING HIGHS/LOWS...AND THERE ARE STILL DIFFERENCES BETWEEN
MODELS ON MAGNITUDE OF COOLING...SO I DID NOT FAVOR THE COLDEST
GUIDANCE DURING THIS UPDATE. THE TYPE OF AIR MASS CURRENTLY
ADVERTISED BY EVEN THE "WARMER" GFS WOULD SUPPORT OVERNIGHT LOWS IN
THE SINGLE DIGITS BELOW ZERO OVER PARTS OF OUR CWA DESPITE CLOUD
COVER (AND IF WE CLEAR OUT MUCH COLDER THAN THIS). CLOUDS COULD
LIMIT DAYTIME WARMING...AND ONGOING FORECAST OF TEENS-LOW 20S FOR
HIGHS MAY BE OPTIMISTIC. REGARDING PRECIP CHANCES...MANY OF THE
PERIODS IN THE EXTENDED HAVE SLIGHT CHANCE-CHANCE POPS...AND I DIDNT
SEE THE NEED TO REMOVE THESE BASED ON THE ACTIVE PATTERN ALOFT...AND
LINGERING BAROCLINIC ZONE ACROSS EASTERN COLORADO. BEST CHANCE FOR
MEASURABLE SNOW IN THESE PERIODS DOES APPEAR TO BE SAT-SAT NIGHT
WHEN A SLIGHTLY STRONGER SHORTWAVE TROUGH MOVES OUT OF THE SW US
ACROSS THE SOUTHERN PLAINS. THERE IS LITTLE IN THE WAY OF MOISTURE
RETURN/MOISTURE ADVECTION...SO ANY SNOWFALL WE SEE THROUGH THESE
PERIODS SHOULD BE ON THE LIGHT SIDE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1048 PM MST TUE FEB 25 2014
SNOW HAS ENDED OR IS ABOUT READY TO END AT BOTH SITES. A CLEARING
TREND IS UNDERWAY. ALTHOUGH IT WILL BE POSSIBLE FOR THE FIRST FEW
HOURS AT KMCK TO HAVE A BRIEF MVFR CEILING. OTHERWISE VFR CEILINGS
CAN BE EXPECTED THROUGH THE REST OF THE PERIOD WITH SHIFTING WINDS
AT 12 KNOTS OR LESS...HIGHEST BETWEEN 18Z AND 00Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...ALW/JSL
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
400 AM EST WED FEB 26 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION THROUGH MIDDAY.
LOW PRESSURE OVER THE GREAT LAKES WILL USHER IN CANADIAN AIR TO
THE REGION THROUGH FRIDAY. A WEAK DISTURBANCE WILL SLIDE ACROSS THE
AREA SATURDAY BEFORE A MORE POTENT LOW PRESSURE SYSTEM BEGINS TO
AFFECT THE REGION EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 0830Z...NO SNOW REPORTED EAST OF THE ALLEGHENY FRONT...BUT
ECHOES ARE INCREASING AND THE CLOUD CEILING IS LOWERING LIKE A
BLANKET OVER THE AREA...PARTICULARLY EAST OF THE BLUE RIDGE. EXPECT
LIGHT TO MODERATE SNOW REPORTS TO BECOME COMMON 5-7AM WITH THE MOST
INTENSE RATES FROM 7-11AM BEFORE A QUICK CHANGEOVER TO SCATTERED
FLURRIES THROUGH MIDDAY...SOMEWHAT LIKE THE SNOW FROM TUESDAY (WITH
AN EARLIER ONSET AND MORE WIDESPREAD ACCUMULATIONS).
06Z HRRR HAS SHIFTED MAX OF SNOW (3-4") OVER WRN DC SUBURBS DOWN TO
RAPPAHANNOCK COUNTY. THE PREVIOUS SEVERAL RUNS HAD PUT A MAX OF 4+"
OVER CULPEPER COUNTY. ACCORDING TO THE 00Z GFS/ECMWF...THE JET
STREAM AXIS WILL BE OVER NRN SECTIONS OF THE CWA WITH THE SRN 2/3 IN
THE RIGHT ENTRANCE REGION THROUGH THE MORNING HOURS. UPPER TROUGH IS
STILL BROAD WITH NO DISCERNIBLE AXIS AT H5. NWLY FLOW IS EXPECTED TO
SPREAD OVER THE AREA MIDDAY THROUGH THE AFTERNOON WHICH WOULD
DOWNSLOPE AND LIMIT PRECIP TO SCATTERED FLURRIES.
TONIGHT...NLY FLOW AS SFC HIGH SPREADS IN ALONG MASON-DIXON LINE.
HOWEVER...A DEVELOPING LOW OVER THE GREAT LAKES BEGINS TO INFLUENCE
THE AREA BRINGING A SLY FLOW BY LATE TONIGHT. MIN TEMPS IN CLEAR
CONDITIONS GENERALLY MID TEENS.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
THE QUICK EXIT OF TODAY`S SYSTEM WILL ALLOW THE AREA TO CLEAR OUT
INTO EARLY THU. WINDS WILL ACTUALLY SWITCH BACK TO SLY FOR A BRIEF
PERIOD AS HIGH PRESSURE SQUEEZING IN BETWEEN THE EXITING SYSTEM AND
THE NEXT WAVE OF POLAR AIR. THE WED STORM SYSTEM WILL HAVE GRABBED
ESSENTIALLY ALL OF THE AVAILABLE MOISTURE FROM THE GULF
REGION...TAKING IT OFF THE COAST AHEAD OF THE APPROACHING UPPER VORT
FROM THE GREAT LAKES REGION.
WED NIGHT WILL BE A COLD NIGHT...BUT W/ THE ARRIVAL OF THIS LATEST
WAVE OF ARCTIC AIR...THU NIGHT WILL LIKELY BE A FEW DEG COLDER AND
SEVERAL DEG DRIER IN TERMS OF DEWPOINTS. A VERY DRY AIRMASS W/
DEWPOINTS BELOW ZERO ACROSS THE REGION AND ADEQUATE RADIATING TO
ALLOW TEMPS TO DROP WELL INTO THE TEENS AND SINGLE DIGITS. THE NIGHT
WILL ALSO START OFF W/ A STEADY NW BREEZE WHICH WILL ONLY FURTHER
DROP WIND CHILL VALUES INTO THE SINGLE DIGITS AND TOWARD ZERO. THIS
LATEST ANOMALOUSLY COLD AIRMASS THOUGH WILL BE ANOTHER QUICK-HITTER
W/ AN WELL ON ITS WAY TOWARD NEW ENGLAND THU NIGHT INTO EARLY FRI.
THE VORT`S EXIT WILL MEAN A SUBSTANTIAL DROP OFF IN WINDS ON
FRI...NEAR CALM EVEN DURING THE DAYTIME HRS. BUT THE ARCTIC AIRMASS
WILL HAVE LEFT SUCH DRY AIR IN ITS WAKE THE TEMPS WILL HAVE A TOUGH
TIME RECOVERING MUCH ABOVE THE M20S BY AFTN - EVEN UNDER AMPLE SUN.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
WHILE TEMPS MAKE A SLOW/STEADY RECOVERING HEADING INTO THE
WEEKEND...ZONAL UPPER FLOW WILL BE ANYTHING BUT SLOW IN BRINGING IN
THE NEXT COUPLE OF LOW PRESSURE WAVES. THE FIRST WILL BE A WEAKLY
ORGANIZED SHORTWAVE W/ LITTLE MOISTURE INVOLVED AND ONLY BRIEFLY
BRINGING THE CHANCE FOR SOME LIGHT PRECIP DURING THE DAY DURING
MOVING OFF THE COAST. ANY PRECIP FALLING DURING THE MRNG HRS ON SAT
MAY BE SNOW BUT TEMPS ARE EXPECTED TO GRADUALLY RISE INTO THE M-U30S
BY AFTN...SO LIQUID PRECIP WILL BE MORE LIKELY W/ ANY RESIDUAL
SHOWERS.
FOCUS THEN TURNS TO A LARGE SCALE AND POTENT STORM SYSTEM DEVELOPING
ACROSS A BULK OF THE CONUS. MULTIPLE WAVES OF ENERGY WILL COMBINE
OVER THE WRN HALF OF THE COUNTRY SAT INTO SUN...PUSHING INTO THE
PLAINS AND EVENTUALLY TOWARD THE EAST COAST LATE SUN INTO MON. THE
WARM FRONT WILL FOR A TIME EXTEND ALL THE WAY FROM THE ROCKIES TO
THE ATLC COAST...SETTLING ALONG AND NORTH OF THE MASON-DIXON LINE AS
THE SYSTEM APR ROACHES. THE FREEZING LINE WILL ALSO BE HOVERING
AROUND THIS AREA SUN AND MON W/ PERIODIC WAVES OF LIGHT PRECIP
SLIDING BY DURING THE TIME. WILL MONITOR LONG TERM GUIDANCE TRENDS
FOR THE BULK OF EXPECTED PRECIP TO PASS OVER THE REGION...00Z RUNS
LOOKING LIKE LATE SUN INTO MON...W/ SOME LINGERING PRECIP INTO
TUE. THE BACK EDGE OF THE PRECIP MAY BE A RAIN/SNOW MIX W/ SNOW IN
THE NW PERIPHERY OF THE AREA W/ CURRENT TRENDS.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
SNOW ONSET 9 TO 11Z ACROSS THE TERMINALS WITH LIGHT TO MODERATE SNOW
THEN UNTIL 15-17Z AND FLURRIES EARLY THIS AFTERNOON. IFR CONDS IN
HEAVIEST PERIOD WITH LIFR IN MODERATE SNOW BY DEFINITION. VFR WITH
NWLY FLOW GUSTING TO 25 KT THIS AFTERNOON. NLY FLOW THIS
EVENING...SWINGING AROUND TO SLY BY DAYBREAK THURSDAY.
A DEEP AND COLD UPPER TROUGH WILL ENCOMPASS THE EAST COAST DURING
THE MIDDLE OF THE WEEK...BRINGING GUSTY WINDS TO THE AREA WED AND
THU. ONLY A BRIEF PERIOD OF SNOW POSSIBLE WED MRNG AS ONE WAVE OF
THIS SYSTEM MOVES ACROSS THE AREA BUT ONLY LIGHT AMTNS EXPECTED. THE
AREA WILL CLEAR OUT LATER IN THE DAY WED...STAYING DRY AND QUIET
INTO THE WEEKEND.
&&
.MARINE...
LIGHT EAST FLOW EARLY THIS MORNING BECOMES WEST AND INTENSIFIES
LATER THIS MORNING...WITH STRONG NWLY FLOW THIS AFTERNOON. SCA FOR
ALL WATERS STARTS AT 8AM...BUT AREAS OF SNOW WILL KEEP WINDS DOWN
PROBABLY UNTIL THE LATE MORNING. NWLY GUSTS OF 25 KT EXPECTED THIS
AFTERNOON. SCA CONTINUES FOR ALL BUT THE WESTERN TRIBUTARIES THROUGH
THE EVENING FOR NLY CHANNELING FLOW WITH GUSTS AROUND 20 KT. FLOW
ACTUALLY BECOMES SLY AFTER MIDNIGHT AS HIGH PRESSURE SETS UP
OFFSHORE.
WINDS WILL PICK BACK UP ON THU BUT NOT AS INTENSE AS WED...THOUGH
SMALL CRAFT CONDITIONS WILL BE POSSIBLE - POTENTIALLY GALE. WINDS
WILL DROP OFF FRI AND INTO THE WEEKEND W/ ONLY SOME BRIEF
CHANNELING INTO EARLY NEXT WEEK.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR DCZ001.
MD...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 11 AM EST
THURSDAY FOR MDZ501.
WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR MDZ004>007-
009>011-013-014-016>018.
VA...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 11 AM EST
THURSDAY FOR VAZ503-504.
WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ037>040-
042-050>057-501-502.
WV...WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 11 AM EST
THURSDAY FOR WVZ501-503-505-506.
WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR WVZ501-505.
MARINE...SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR ANZ530>534-537-539>541-543.
SMALL CRAFT ADVISORY FROM 8 AM TO 6 PM EST THURSDAY FOR
ANZ530>543.
SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 6 PM EST THIS
EVENING FOR ANZ535-536-538-542.
&&
$$
SYNOPSIS...BAJ
NEAR TERM...BAJ
SHORT TERM...GMS
LONG TERM...GMS
AVIATION...BAJ/GMS
MARINE...BAJ/GMS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
246 AM EST WED FEB 26 2014
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION THROUGH MIDDAY.
LOW PRESSURE OVER THE GREAT LAKES WILL USHER IN CANADIAN AIR TO
THE REGION THROUGH FRIDAY. A WEAK DISTURBANCE WILL SLIDE ACROSS THE
AREA SATURDAY BEFORE A MORE POTENT LOW PRESSURE SYSTEM BEGINS TO
AFFECT THE REGION EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
QUICK UPDATE TO ADD GREENE AND ALBEMARLE TO THE ADVISORY. NO SNOW
REPORTED YET EAST OF THE ALLEGHENY FRONT THOUGH ECHOES SOUTH OF DC
ARE MOISTENING THE COLUMN. 05Z HRRR CONTINUES TREND OF RECENT HOUR
RUNS OF A SNOW MAX IN N-CNTRL VA CENTERED OVER CULPEPER COUNTY
LOCAL AMOUNTS OF 5 INCHES. IT DOES NOT TAKE MUCH IN A COLD AIRMASS
SUCH AS THIS TO GET SEVERAL INCHES FROM BANDS AND A WARNING MAY BE
NECESSARY IN THE NOWCAST PHASE. ELSEWHERE...DEPICTION IS
CONSISTENT OF A REDUCTION IN SNOW (LESS THAN AN INCH) BETWEEN THE
ALLEGHENY FRONT AND BLUE RIDGE AND 1-3 INCHES FROM THE CENTRAL VA
FOOTHILLS TO ACROSS THE BALTIMORE-WASHINGTON METRO AREA AND SRN
MD PRIMARILY BETWEEN 10 TO 16Z.
ADJUSTED BACK END OF PRECIP WITH FOR SCATTERED FLURRIES THAT
CONTINUE THROUGH THE EARLY AFTERNOON.
PREVIOUS...
LATEST ANALYSIS SHOWS SHORTWAVE ENERGY RACING THROUGH IN A ZONAL
FLOW ALOFT ACROSS THE MIDWEST INTO THE OHIO VALLEY. A STRONGER
SHORTWAVE OVER THE UPPER MIDWEST WILL QUICKLY DROP SOUTHEAST AND
SWING THROUGH OUR AREA LATE TONIGHT INTO WEDNESDAY MORNING. DEEP
SYNOPTIC LIFT IS EXPECTED IN THE RIGHT REAR ENTRANCE OF THE UPPER-
LEVEL JET...AND THIS CAN ALREADY BE SEEN IN THE INFRARED SATELLITE
IMAGERY WITH COOLING CLOUD TOPS ACROSS THE MIDWEST AND OHIO
VALLEY. RADAR TRENDS ARE ALSO INCREASING ACROSS THESE AREAS.
CLOUDS WILL LOWER AND THICKEN OVERNIGHT AND SNOW IS EXPECTED TO
OVERSPREAD THE AREA FROM WEST TO EAST AFTER MIDNIGHT. DESPITE
LIMITED MOISTURE...FORCING SHOULD BE STRONG ENOUGH FOR SNOWFALL
ACCUMULATIONS ACROSS MOST OF THE AREA. A WINTER WEATHER ADVISORY
REMAINS IN EFFECT FOR THE WASHINGTON AND BALTIMORE METROPOLITAN
AREAS AS WELL AS THE VIRGINIA PIEDMONT AND SOUTHERN MARYLAND.
LATEST GUIDANCE CONTINUES TO SHOW THAT THE BEST POTENTIAL FOR
MESOSCALE BANDING EXISTS ACROSS THESE AREAS WITH POTENT FN VECTOR
CONVERGENCE LINING UP WITH THE AREA OF MAXIMUM DENDRITIC SNOW
GROWTH AND SATURATED CONDITIONS. SNOWFALL ACCUMULATIONS WILL
AVERAGE BETWEEN ONE AND TWO INCHES ACROSS THESE AREAS...BUT
LOCALLY HIGHER AMOUNTS AROUND THREE INCHES ARE POSSIBLE DUE TO THE
POTENTIAL OF BANDING PRECIPITATION. TEMPS WILL BE PLENTY COLD FOR
SNOW...RANGING FROM THE TEENS IN THE MOUNTAINS TO THE 20S
ELSEWHERE EARLY WEDNESDAY MORNING. THEREFORE...SNOW COVERED ROADS
AND SLIPPERY CONDITIONS ARE EXPECTED DURING THE MORNING RUSH.
A WINTER WEATHER ADVISORY IS ALSO IN EFFECT FOR PORTIONS OF WEST
VIRGINIA ALONG AND WEST OF THE ALLEGHENY FRONT DUE TO AN UPSLOPE
COMPONENT TO THE LOW-LEVEL FLOW.
HIGH PRESSURE WILL APPROACH THE AREA WEDNESDAY AFTERNOON...BUT
BLUSTERY AND COLD CONDITIONS ARE EXPECTED AS NORTHWEST WINDS
INCREASE DUE TO A STRENGTHENING GRADIENT BETWEEN THE APPROACHING
HIGH AND LOW PRESSURE DEVELOPING WELL OF THE MID-ATLANTIC COAST.
FLURRIES ARE POSSIBLE WEDNESDAY AFTERNOON AS COLD ADVECTION
COMBINING WITH THE HIGHER SUN ANGLE CAUSES SOME INSTABILITY.
HOWEVER...NO ADDITIONAL SNOWFALL ACCUMULATION IS EXPECTED.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
COLD HIGH PRESSURE WILL BUILD INTO THE MIDDLE ATLANTIC REGION
WEDNESDAY NIGHT. GUSTY NORTHWEST WINDS WILL DIMINISH AND
TEMPERATURES WILL FALL BACK INTO THE TEENS IN MOST AREAS EXCEPT
0 TO 5 ABOVE ACROSS THE ALLEGHENY FRONT. HIGH TEMPERATURES WILL
AVERAGE WELL BELOW NORMAL THURSDAY AFTERNOON WITH ANOTHER COLD
FRONT BRINGING A REINFORCING SHOT OF ARCTIC AIR THURSDAY
AFTERNOON/EVENING. OVERNIGHT LOWS THURSDAY NIGHT WILL FALL BACK TO
THE LOWER TO MIDDLE TEENS AREA WIDE EXCEPT 0 ABOVE TO 5 BELOW ZERO
ACROSS THE ALLEGHENY FRONT. GUSTY NORTHWEST WINDS MAY LEAD TO A
PERIOD OF BELOW ZERO WIND CHILLS THURSDAY NIGHT OVER WESTERN
SECTIONS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL MOVE ACROSS THE REGION FRIDAY...MAKING IT TO THE
EAST COAST BY FRIDAY NIGHT. WINDS WILL BE LIGHT AND VARIABLE FRIDAY
THEN BECOME SOUTHERLY FRIDAY NIGHT. TEMPERATURES WILL BE ABOUT 15 TO
20 DEGREES BELOW NORMAL FRIDAY AND 5 TO 10 DEGREES BELOW NORMAL
FRIDAY NIGHT.
SOME UPPER LEVEL ENERGY WILL BRING A CHANCE FOR SOME RAIN OR SNOW
SHOWERS LATE FRIDAY NIGHT AND SATURDAY.
A STATIONARY FRONT WILL DEVELOP ALONG THE OHIO VALLEY AND INTO THE
MID-ATLANTIC REGION SUNDAY AND PERSIST INTO MONDAY. THIS FRONT WILL
BE THE FOCAL POINT OF RAIN OR SNOW...MAINLY SUNDAY NIGHT AND
MONDAY. THE EURO MODEL HAS A LOW PRESSURE SYSTEM FORMING ALONG
THIS FRONT AND MOVING NORTHEAST ALONG THE SHENANDOAH VALLEY TOWARD
PENNSYLVANIA AND NEW YORK. THE GFS MODEL HAS A LOW PRESSURE
SYSTEM FORMING ALONG THE FRONT...AS WELL...BUT TAKES THE LOW
FURTHER SOUTH AND EAST THAN THE ECMWF.
THESE DIFFERENCES MAKE IT DIFFICULT TO PINPOINT WHO WILL RECEIVE
RAIN AND WHO WILL RECEIVE SNOW. THERE IS AT LEAST A CHANCE OF EITHER
PRECIPITATION TYPE WITH A LIKELY POP OF RAIN OR SNOW MONDAY.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
CIGS/VSBYS WILL DETERIORATE EARLY WEDNESDAY MORNING AS BANDS OF
SNOW DEVELOP OVER THE TERMINALS. IFR CONDITIONS ARE EXPECTED
DURING THIS TIME. CIGS/VSBYS WILL IMPROVE LATE WEDNESDAY MORNING
AND AFTERNOON AS NORTHWEST WINDS USHER IN DRIER CONDITIONS.
HOWEVER...A FEW FLURRIES CANNOT BE RULED OUT WEDNESDAY AFTERNOON.
NORTHWEST WINDS WILL GUST AROUND 20 TO 25 KNOTS DURING THIS TIME.
VFR CONDITIONS EXPECTED WEDNESDAY NIGHT THROUGH THURSDAY NIGHT.
GUSTY NORTHWEST WINDS OF 15 TO 25 KTS WILL IMPACT THE TERMINALS
THURSDAY AFTERNOON INTO THE EVENING. WINDS WILL DIMINISH DURING
THE NIGHT.
VFR CONDITIONS FRIDAY. MVFR CONDITIONS CAN`T BE RULED OUT WITH A
CHANCE OF RAIN OR SNOW FRIDAY NIGHT THROUGH MONDAY. IF IFR
CONDITIONS DO EXIST...THERE IS A BETTER CHANCE SUNDAY NIGHT INTO
MONDAY ALONG A STATIONARY FRONT AND A DEVELOPING LOW PRESSURE
SYSTEM.
&&
.MARINE...
A SHORTWAVE WILL PASS THROUGH THE WATERS WEDNESDAY
MORNING...TRIGGERING A PERIOD OF SNOW. NW FLOW 15-20 KT SUSTAINED
BEHIND THE FRONT. SCA IN EFFECT FOR WED...CONTINUING FOR NLY FLOW
OVER ALL BUT THE WRN TRIBS WEDNESDAY EVENING.
A COLD FRONT WILL PUSH THROUGH THE WATERS ON THURSDAY BRINGING THE
LIKELIHOOD OF SCA CONDITIONS TO ALL OF THE WATERS. WINDS WILL FALL
BELOW SCA LEVELS BY THURSDAY NIGHT.
NO MARINE HAZARDS EXPECTED FRIDAY THROUGH SUNDAY. SMALL CRAFT
ADVISORIES SUNDAY NIGHT AND MONDAY WOULD DEPEND ON THE POSITION OF
A STATIONARY FRONT AND THE TRACK OF AN ATTACHED LOW PRESSURE
SYSTEM.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR DCZ001.
MD...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR MDZ004>007-
009>011-013-014-016>018.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ037>040-
042-050>057-501-502.
WV...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR WVZ501-505.
MARINE...SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 11 PM EST THIS
EVENING FOR ANZ530>534-537-539>541-543.
SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 6 PM EST THIS
EVENING FOR ANZ535-536-538-542.
&&
$$
UPDATE...JACKSON
PREVIOUS...BJL/KRW/KLW/HTS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
417 AM EST WED FEB 26 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 400 PM EST TUE FEB 25 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A FAMILIAR PATTERN
FEATURING A DEEP UPR TROF OVER ERN NAMERICA DOWNSTREAM OF A RDG
ALONG THE W COAST. SHRTWV EMBEDDED IN THE NW FLOW IS STREAKING SEWD
THRU ONTARIO JUST N OF LK SUP. COLD FNT ASSOCIATED WITH THIS
DISTURBANCE HAS PASSED THRU THE CWA...AND H85 TEMPS AS LO AS -25C TO
-28C ARE PUSHING INTO UPR MI IN THE LLVL W FLOW. ALTHOUGH THERE IS A
GOOD DEAL OF ICE ON LK SUP...AREAS OF OPEN WATER OVER THE FAR WRN LK
AND OVER THE SCENTRAL E OF THE KEWEENAW HAVE ALLOWED A GOOD DEAL OF
LK CLD/SOME -SHSN TO FORM IN THE LLVL CAD. THE LK CLDS/SHSN APPEAR
TO BE MOST WDSPRD OVER THE NE HALF OF THE AREA CLOSER TO THE SHRTWV
PASSING THRU ONTARIO/ACCOMANPANYING DYNAMIC SUPPORT AND DEEPER MSTR.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE LK EFFECT CLD/SHSN
TRENDS AND TEMPS/NEED FOR WIND CHILL HEADLINES.
LATE THIS AFTN/TNGT...AS THE H925 FLOW VEERS MORE TO THE NW THRU 00Z
IN THE WAKE OF SHRTWV PASSING BY TO THE N...EXPECT LK EFFECT
CLDS/SHSN TO SPREAD FARTHER TO THE S AND INLAND IN THE PRESENCE OF
LENGTHENING DAYTIME HEATING DESPITE DNVA/DEEP LYR QVECTOR DVGC IN
THE WAKE OF THE SHRTWV PASSAGE. H85 THERMAL TROF WITH TEMPS DOWN TO
-28/-29C IS FCST TO SHIFT THRU THE CWA BTWN 06Z-12Z AS THE LLVL FLOW
BACKS TO THE W BTWN SFC HI PRES SINKING TOWARD THE MID MS RIVER
VALLEY AND NEXT VIGOROUS SHRTWV DROPPING SEWD THRU SCENTRAL CANADA.
WITH A PERIOD OF LARGER SCALE QVECTOR DVGC...EXPECT CLRG OVER THE
INTERIOR...ALLOWING SFC TEMPS TO FALL WELL BLO ZERO AND INTO THE
TEENS BLO ZERO AT SOME PLACES UNDER DRY AIRMASS WITH PWAT UNDER 0.10
INCH. ALTHOUGH THERE ARE QUESTIONS AS TO WHETHER SFC WINDS WL
CONSISTENTLY SATISFY THE 10 MPH SPEED THRESHOLD FOR A WIND CHILL
ADVY...PLAN TO ISSUE AN ADVY FOR THE COLDER NW HALF OF THE CWA WITH
FAIRLY SHARP PRES GRADIENT/H925 WINDS IN THE 20-30KT RANGE UNDER H85
THERMAL TROF ENHANCING MIXING. LK EFFECT CLDS/-SHSN WL SHIFT FM THE
NW WIND SN BELTS BACK INTO AREAS IMPACTED BY W WINDS LATE TNGT.
ABSENCE OF DGZ WITHIN VERY COLD AIRMASS AND ICE COVER WL LIMIT SN
ACCUMS.
WED...AREA OF DEEP LYR QVECTOR CNVGC IN ADVANCE OF SHRTWV/SFC LO
DIGGING SEWD THRU NW ONTARIO WL OVERSPREAD UPR MI NW-SE BY EARLY
AFTN. IN THE ABSENCE OF ANY SGNFT MSTR INFLOW...SUSPECT DRYNESS OF
ANTECEDENT AIRMASS WL BE A SGNFT IMPEDIMENT TO OUTBRREAK OF PCPN. AS
THE FLOW SHIFTS TO THE SW...THERE IS POTENTIAL FOR SOME LK
MOISTENING/ENHANCEMENT OFF OF LK MI. BUT EXTENSIVE/GROWING ICE COVER
OVER THE N HALF OF LK MI WL TEND TO MITIGATE THIS IMPACT. TENDED
TOWARD THE HIER CHC/LIKELY POPS OVER THE NE HALF OF THE CWA TOWARD
SHARPER ISENTROPIC ASCENT ON THE 270K SFC /NEAR H7/ AND ALSO LATE IN
THE DAY OVER THE W WITH EXPECTED ARRIVAL OF ENHANCED LLVL CNVGC
ASSOCIATED WITH COLD FNT ATTENDANT TO CLIPPER LO REACHING NE LK SUP
BY 00Z THU.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 416 AM EST WED FEB 26 2014
AT 12Z THURSDAY THE MAIN 500MB LOW WILL BE SET UP FROM S HUDSON BAY
THROUGH N LAKE HURON...WITH QUICK NW FLOW AND SEVERAL ELONGATED
DISTURBANCES STILL MOVING THROUGH UPPER MI. THE STRONG WINDS THAT
WILL STILL BE AROUND AT DAYBREAK THURSDAY ARE STILL EXPECTED TO
DIMINISH PRETTY QUICKLY DURING THE DAY...WITH THE WEAKENING PRESSURE
GRADIENT AS THE SFC LOW PUSHES ACROSS THE S ONTARIO/QUEBEC BORDER BY
18Z...AND THE STRONG HIGH OVER THE DAKOTAS SHIFTS TO MN AND IA WHICH
WILL ALLOW FOR RIDGING OVER THE W HALF OF THE CWA. MOMENTUM TRANSFER
FALLS BELOW 25KTS AT IWD AROUND 15Z...CMX AT 18Z...1-2HRS LATER AT
SAW...AND AROUND 21Z AT P53. WIND CHILL WARNINGS/ADVISORIES WILL
CONTINUE UNTIL 17 OR 18Z.
CONFIDENCE IN HIGH SNOW AMOUNTS TO POST ANYTHING MORE THAN WINTER
WEATHER ADVISORIES IS LOW GIVEN THE SIGNIFICANT ICE ACROSS LAKE
SUPERIOR. HAS BEEN AMAZING TO SEE HOW QUICKLY NEW ICE HAS BEEN ABLE
TO FORM IN OUR COLD AIR OVER THE PAST 24HRS. WINTER WEATHER ADVISORY
WILL LINGER THROUGH MID-LATE MORNING ACROSS THE KEWEENAW
PENINSULA...AND MID AFTERNOON FOR ALGER/N. SCHOOLCRAFT/LUCE
COUNTIES. MAY NEED TO INCORPORATE FAR N AND E MQT COUNTY INTO WINTER
WEATHER ADVISORY FOR BLOWING/DRIFTING SNOW. THE WORST CONDITIONS ON
M-26 BETWEEN MQT AND MUNISING WILL LIKELY BE 10-18Z THURSDAY.
RECORD BREAKING LOW-HIGH TEMPERATURES THURSDAY STILL LOOK
REASONABLE. 850MB TEMPS OF -30 TO -33C WILL LINGER OVERHEAD THROUGH
THE DAY...WITH -36 TO -38C OVER CENTRAL ONTARIO. AS NOTED IN
PREVIOUS DAYS...THESE VALUES ACROSS THE CWA ARE SIMILAR TO 850MB
TEMPS FROM JANUARY 27TH AND HIGHS THAT DAY WERE IN THE SINGLE DIGITS
BELOW ZERO OVER THE WEST...AND AT OR JUST ABOVE FREEZING OVER THE
EAST. ALL-TIME COLDEST HIGH TEMP RECORDS FOR FEB 27TH ARE GENERALLY
IN THE MID SINGLE DIGITS ABOVE ZERO (WITH AT LEAST 6 DATING BACK
BEFORE 1925).
LOOK FOR EXTREMELY COLD TEMPERATURES THURSDAY NIGHT AS THE SFC HIGH
SINKS TO S WI AND IL BY 00Z...OVER LOWER MI THROUGH THE OHIO VALLEY
AT 06Z FRIDAY...AND FINALLY ACROSS THE LOWER GREAT LAKES/MID
ATLANTIC BY 12Z FRIDAY. WITH THE SFC RIDGE OVERHEAD MOST OF THE
NIGHT...EXPECT LIGHT WINDS. CLOUDS COULD KEEP TEMPS FROM FALLING TOO
LOW...PARTICULARLY OVER THE N HALF OF THE CWA. THE GFS AND NAM STILL
HAVE PLENTY OF LLV MOISTURE STUCK BELOW 850MB...WITH ADDITIONAL MID
CLOUDS LIKELY SLIDING IN OVERNIGHT FROM THE W OVER THE FAR N. THE
BAND OF MID CLOUDS S WILL LIKELY REMAIN JUST TO THE S THROUGH 12Z
FRIDAY. ALTHOUGH TEMPERATURES WILL BE VERY LOW /ONCE AGAIN POSSIBLY
RECORD BREAKING/...WIND CHILLS WILL NOT BE AS LOW...AND
WARNINGS/ADVISORIES WILL LIKELY NOT BE POSTED DUE TO THE LIGHT WINDS.
THE CHANCES FOR LIGHT SNOW WILL GREATLY DIMINISH THURSDAY NIGHT INTO
EARLY FRIDAY...BEFORE THE NEXT SYSTEM SLIDES IN FROM THE W-SW WITH
SCATTERED SNOW/SNOW SHOWERS DEVELOPING OVER MAINLY CENTRAL/E UPPER
MI DURING THE DAY FRIDAY. EXPECT S-SSW WINDS AHEAD OF THE LOW
SHIFTING FROM THE PLAINS STATES AT 12Z FRIDAY WILL DEEPEN SLIGHTLY
AS IT PUSHES ACROSS W UPPER MI/LAKE SUPERIOR AT 00Z SATURDAY...AND E
OF LAKE SUPERIOR/UPPER MI BY 12Z SATURDAY. THE S-SSW SHOULD RESULT
IN LAKE ENHANCED SNOW E OF ESC ALONG LAKE MI FRIDAY AFTERNOON/FRIDAY
EVENING. WILL NOT GO TOO HIGH WITH POPS AT THIS TIME...BUT POPS MAY
NEED TO BE INCREASED S CENTRAL AND E ALONG THE LAKE MI BORDER AS
FCST MODELS ARE STARTING TO ALIGN TO A COMMON THEME. LITTLE TO NO
SNOW IS EXPECTED FAR W.
STRONGER HIGH PRESSURE OVER S CENTRAL CANADA AND THE N PLAINS
SATURDAY WILL SLOWLY SLIDE OVER THE UPPER GREAT LAKES THROUGH MUCH
OF THE REST OF THE PERIOD. LAKE EFFECT SNOW SHOWERS ACROSS N UPPER
MI WILL GREATLY DEPEND ON THE AMOUNT OF ICE COVER...BUT WITH
SIGNIFICANT ICE LIKELY REMAINING...KEPT POPS MAINLY IN THE SLIGHT
CHANCE CAT THROUGH THE REST OF THE PERIOD. NO SIGNIFICANT WARM UP
EXPECTED TO NORMAL VALUES ANTICIPATED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 634 PM EST TUE FEB 25 2014
WINDS BEGINNING TO ABATE SLIGHTLY AT ALL THREE TAF SITES THIS
EVENING. WINDS ARE TO GRADUALLY DIMINISH OVERNIGHT AS THEY BACK TO
THE SSW/SW BY DAYBREAK...AND THEN WILL PICK UP AS THE MORNING
PROGRESSES...WITH GUSTS TO 22-23KTS COMMON DURING THE LATE MORNING
AND AFTERNOON HOURS. AT KCMX...LIFR/IFR VISIBILITIES DUE TO BRIEF
LES SNOW BANDS AND GUSTY WINDS CHANNELED THROUGH THE TERRAIN THERE
WILL EVENTUALLY IMPROVE AFTER 6Z AS WINDS DIMINISH AND DRIER AIR
WORKING IN FROM THE WEST DIMINISHES LES. OTHERWISE...MVFR/VFR
CONDITIONS PREVAIL AT KIWD AND KSAW WITH MVFR DEVELOPING AT KCMX BY
9Z...AND WILL CONTINUE THROUGH THE FORECAST. IFR VISIBILITY
CONDITIONS MAY REDEVELOP AT KCMX WEDNESDAY AFTERNOON AS WINDS SHIFT
BACK TO THE WEST AND PICK UP AND LES REDEVELOPS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 PM EST TUE FEB 25 2014
NW WINDS UP TO 25-30 KTS LATE TODAY UNDER SHARP PRES GRADIENT
BETWEEN SFC HI OVER THE NCENTRAL PLAINS AND LO PRES IN EASTERN
ONTARIO WILL SLOWLY BACK TO THE SW ON WED AS THE HI MOVES INTO THE
MID MS RIVER VALLEY AND ANOTHER LO PRES SYSTEM DIVES SE INTO NW
ONTARIO. THERE MAY BE SOME GALE FORCE GUSTS TO 35 KTS OVER THE W
HALF OF THE LAKE WHERE FUNNELING OF THIS FLOW RESULTS IN SPEED
ENHANCEMENT. ONCE THE LO SHIFTS TO THE E OF THE LAKE ON WED NIGHT
AS THE PRES GRADIENT TIGHTENS AGAIN E OF HI PRES MOVING INTO THE
NORTHERN PLAINS...N GALES UP TO 35-45 KTS WILL DEVELOP OVER THE
ENTIRE LAKE. THE CLOSER APPROACH OF THE HI CENTER AND WEAKER PRES
GRADIENT WILL CAUSE THE GALES TO DIMINISH W TO E ON THU. ISSUED A
GALE WATCH FOR THE ENTIRE LAKE. EXPECT WINDS UNDER 25 KTS THE REST
OF THE FORECAST PERIOD WITH A RELATIVELY WEAK PRES GRADIENT
DOMINATING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL WARNING FROM 3 AM EST /2 AM CST/ TO NOON EST /11 AM
CST/ THURSDAY FOR MIZ001>005-009>011-084.
WIND CHILL ADVISORY UNTIL 10 AM EST /9 AM CST/ THIS MORNING FOR
MIZ001>005-009>011-084.
WINTER WEATHER ADVISORY FROM 2 AM TO 3 PM EST THURSDAY FOR
MIZ006-007-085.
WIND CHILL ADVISORY FROM 6 AM EST /5 AM CST/ TO NOON EST /11 AM
CST/ THURSDAY FOR MIZ006-007-012>014-085.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EST
THURSDAY FOR MIZ001-003.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 1 PM EST THURSDAY FOR LSZ243>245-
248>251-264>267.
GALE WARNING FROM 11 PM EST /10 PM CST/ THIS EVENING TO 8 AM EST
/7 AM CST/ THURSDAY FOR LSZ240>242-263.
GALE WARNING FROM 7 PM EST /6 PM CST/ THIS EVENING TO 6 AM EST
/5 AM CST/ THURSDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...RJT
MARINE...KC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
349 AM EST WED FEB 26 2014
.SYNOPSIS...
A PROLONGED STRETCH OF COLD WEATHER...WITH TEMPERATURES RUNNING
10 TO 20 DEGREES BELOW AVERAGE...IS EXPECTED TO PERSIST THROUGH
EARLY NEXT WEEK. REINFORCING ARCTIC FRONTS MOVING FROM WEST TO
EAST ACROSS THE NORTH COUNTRY THIS MORNING AND AGAIN DURING THE
MIDDAY THROUGH AFTERNOON HOURS THURSDAY WILL BRING SCATTERED SNOW
SHOWERS AND SNOW SQUALLS. A QUICK DUSTING TO A COUPLE INCHES OF SNOW
IS POSSIBLE WITH THESE FRONTAL PASSAGES...ALONG WITH BRIEF PERIODS
OF VERY LOW VISIBILITY. HIGH TEMPERATURES TODAY WILL RANGE FROM
THE MID TEENS TO LOWER 20S...AND DEVELOPING WESTERLY WINDS OF 15
TO 25 MPH WILL RESULT IN WIND CHILL VALUES NEAR ZERO.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 342 AM EST WEDNESDAY...VARIABLE CLOUD COVER...WIND AND
WEATHER CONDITIONS TODAY WITH REINFORCING ARCTIC FRONTAL PASSAGE
FROM WEST-TO-EAST EXPECTED LATER THIS MORNING. EXCELLENT
CONVERGENCE NOTED ALONG APPROACHING SECONDARY/ARCTIC FRONT ACROSS
ERN LAKE ONTARIO AND WRN NY EARLY THIS AM. EARLY AM RUC MODEL
ANALYSIS INDICATES THE FRONT IS ASSOCIATED WITH STRONG SFC-925MB
FRONTOGENESIS WITH ACCOMPANYING ISALLOBARIC RISE/FALL
COUPLET...RESULTING IN ROBUST LINEAR FORCING. LAKE INDUCED
INSTABILITY UP TO 100 J/KG AND STRONG LOW-LEVEL FORCING FOR ASCENT
IS RESULTING IN NARROW CONVECTIVE BAND ALONG THE FRONT PRODUCING
SNOW SQUALL ACTIVITY WITH BRIEF PERIOD OF MODERATE TO HEAVY SNOW
(20-30 MINUTES). BTV SNOW SQUALL PARAMETER MAINTAINS SNOW SQUALL
POTENTIAL AS FRONT SHIFTS EWD CROSSING OUR REGION THIS
MORNING...BEFORE EXITING EAST OF THE CT RIVER VLY BY 18Z.
FAVORABLE FRONTOGENETIC FORCING AND LOW-LEVEL MOISTURE AND
INSTABILITY WILL BRING A BAND OF SNOW SHOWERS AND SQUALLS ACROSS
NRN NY THRU ABOUT 12-13Z. MAY SEE CONVECTIVE ACTIVITY WEAKEN
SLIGHTLY THRU THE CHAMPLAIN VALLEY WITH ABSENCE OF INSTABILITY
LOCALLY AND FLOW DISRUPTION ACROSS THE ADIRONDACK REGION.
INSTABILITY IS ACTUALLY BEST ACROSS NH/ME WITH INSOLATIONAL
HEATING IN ADVANCE OF THE BNDRY...SO AGAIN...ANTICIPATE
ORGANIZATION MAY WANE A BIT THRU THE CHAMPLAIN VLY...BUT INCREASE
AGAIN ACROSS ERN VT MIDDAY HRS BEFORE EXITING RAPIDLY EWD WITH
FROPA BY 17-18Z. SBCAPE VALUES REACH 100-150 J/KG IN NAM MODEL
SOUNDINGS ALONG THE CT RIVER BETWEEN 15-18Z TODAY JUST AHEAD OF
THE FRONTAL BNDRY. WE/LL SEE A QUICK DUSTING TO 2" IN SPOTS WITH
THESE SNOW SHOWERS AND SQUALLS...LIKELY HIGHEST IN NRN NY AND THEN
CENTRAL AND ERN VT. MAY RESULT IN SLOW TRAVEL FOR AN HOUR OR SO
DURING SQUALL PASSAGE. WE/LL CONTINUE TO HIGHLIGHT THIS POTL IN
THE HAZARDOUS WEATHER OUTLOOK AND THROUGH SOCIAL MEDIA.
OTHERWISE...LOOKING AT CONTINUED COLD TEMPS WITH HIGHS IN THE MID
TO UPPER 20S...EXCEPT LOW 20S IN FAR SERN SECTIONS. STEEP LOW-
LEVEL LAPSE RATES WILL CONTRIBUTE TO GUSTY S-SW WINDS IN ADVANCE
OF THE FRONT 15-25 MPH WITH POST- FRONTAL GUSTS TO 30
MPH...SHIFTING INTO THE WEST FOLLOWING FRONTAL PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 342 AM EST WEDNESDAY...SFC RIDGE BUILDS BRIEFLY ACROSS THE AREA
THIS EVENING AND OVERNIGHT...ALLOWING FOR DIMINISHING WIND AND A
PERIOD OF PARTIAL CLEARING. WITH ARCTIC AIR MASS IN PLACE (850MB
TEMPS -24C)...THE RADIATIONAL COOLING WILL RESULT IN COLD
OVERNIGHT LOWS RANGING FROM NEAR ZERO IN THE CHAMPLAIN VALLEY TO
AROUND 10 BELOW IN THE ADIRONDACKS AND NORTHEAST KINGDOM. TEMPS MAY
LEVEL OFF AFTER MIDNIGHT WITH SOME INCREASE IN CLOUDS IN ADVANCE OF
NEXT SYSTEM.
NEXT SHORTWAVE TROUGH ROTATING AROUND THE SRN PERIPHERY OF PARENT
UPPER LOW ANCHORED ACROSS JAMES BAY WILL TRANSLATE ACROSS THE ERN
GREAT LAKES AROUND 12Z THURSDAY...AND ACROSS THE NORTH COUNTRY
15-21Z TIME FRAME THURSDAY. THIS NEXT SHORTWAVE IS APPEARS VIGOROUS
IN WV IMAGERY AND IN NWP PROJECTIONS...SO QG ASCENT WILL BE
MODERATELY STRONG AS UPR TROUGH APPROACHES DURING THE DAY THURSDAY.
IT APPEARS SBCAPE VALUES WILL BE BETTER ACROSS MOST SECTIONS OF THE
NORTH COUNTRY WITH THIS SYSTEM TOMORROW (AS OPPOSED TO THE WEAKER
ONE TODAY)...WITH 06Z NAM INDICATING 100-150 J/KG ACROSS MUCH OF THE
NORTH COUNTRY. ALSO INTERESTING ARE PROGGED PBL HEIGHTS TO 600MB
WITH STEEP LAPSE RATES FROM THE SFC-12 KFT...A DEFAULT TROPOPAUSE IN
THE ARCTIC AIR REGIME. SO...GOOD CONVECTIVE SNOW POTENTIAL.
FRONTOGENETIC FORCING IS NOT AS WELL ORGANIZED AS WEDNESDAY...SO
WOULD ANTICIPATE SMALLER LINE SEGMENTS AND CONVECTIVE CELLS PRODUCING
BRIEF BURSTS OF HEAVIER SNOW SHOWERS AND POSSIBLE SQUALLS WITH
GUSTS 30-35 MPH. A QUICK 1-3" IS POSSIBLE IN SPOTS...AND WILL
AGAIN CAUSE SOME BRIEF TRANSPORTATION HAZARD DUE TO LOW VSBY AND
SNOW COVERED ROADS. MADE MENTION OF THIS AS WELL IN THE MORNING
HWO. HIGHS THURSDAY IN THE UPR TEENS TO LOW 20S. SYSTEM MOVES EAST
OF THE AREA THURSDAY NIGHT WITH JUST A FEW LINGERING MTN FLURRIES.
LOWS AGAIN ZERO TO -10F...BUT LOCALLY COLDER IN THE NRN
ADIRONDACKS IF PARTIAL CLEARING CAN OCCUR LATE.
FRIDAY LOOKS QUIET WITH LOW TO MID LEVEL RIDGING BUILDING INTO THE
REGION FROM THE WEST. SHOULD BE PARTLY TO MOSTLY SUNNY AND KEPT THE
FORECAST DRY. REINFORCED CAA BEHIND THURSDAY/S TROUGH KEEPS 850MB
TEMPS OF -23 TO -24C ACROSS THE REGION FOR FRIDAY. RATHER
INEFFECTIVE SUNSHINE WITH HIGHS IN THE LOW-MID TEENS...AND LOCALLY
8-9F IN THE NRN ADIRONDACK REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 330 AM EST WEDNESDAY...LITTLE CHANGE FROM PREVIOUS COUPLE OF
FCSTS WITH MID/UPPER LVL TROF PREVAILING ACRS THE NE CONUS AND
SEVERAL OPPORTUNITIES FOR ACCUMULATING SNOWFALL FROM SAT THRU NEXT
TUES. WEAK WARM FRNT FEATURE AND SFC LOW PRES TRACKING TO OUR
NORTH WL PRODUCE LIGHT SNOW SHOWERS ACRS OUR CWA ON SATURDAY.
TEMPS SHOULD WARM INTO THE TEENS AND 20S ON SATURDAY. A DUSTING TO
2 INCHES LOOKS LIKELY...WITH HIGHEST VALUES ACRS THE MTNS.
MEANWHILE...LATEST 00Z GUIDANCE IS TRENDING FURTHER SOUTH WITH
SYSTEM ON MONDAY/TUESDAY...AND STRONGER WITH SFC HIGH PRES ACRS
SOUTHERN CANADA. THIS WL PROVIDE CWA WITH COLD AND DRY NORTHERLY
WINDS SUNDAY INTO MONDAY ALONG WITH SUPPRESSING BETTER
MOISTURE/LIFT ACRS THE MID ATLANTIC STATES/SNE. HOWEVER...STILL
NOTICING A SHARP NORTH TO SOUTH LLVL THERMAL GRADIENT ACRS OUR
CWA...ALONG WITH SOME ENHANCED 850 TO 500MB RH MOVING FROM SW TO
NE ACRS OUR REGION. THIS MOISTURE COMBINED WITH SEVERAL EMBEDDED
5H VORT IN THE FAST CONFLUENT WESTERLY FLW ALOFT SHOULD BE ENOUGH
TO PRODUCE A LIGHT ACCUMULATING SNOWFALL ACRS THE REGION ON MONDAY
INTO TUESDAY. FURTHERMORE...STILL THINKING MODELS WL SHIFT BACK
NORTH WITH PROGGED SFC LOW PRES TRACK...ESPECIALLY AS
SYSTEM/ENERGY ALOFT ENTERS THE WESTERN CONUS THIS WEEKEND. WL CONT
TO MENTION HIGH CHC POPS FOR THIS TIME PERIOD AND WAIT UNTIL
BETTER AGREEMENT OCCURS IN GUIDANCE BEFORE INCREASING TO LIKELY
POPS. TEMPS WL CONT TO BE TRICKY...ESPECIALLY ASSOCIATED WITH LLVL
CAA ON SUNDAY INTO MONDAY. LATEST GFS IS SHOWING 925MB TEMPS
DROPPING BTWN -22C AND -26C WITH NORTHERLY WINDS. THIS COMBINED
WITH INCREASING HIGH CLOUDS FROM APPROACHING SOUTHERN STREAM
SYSTEM SUPPORTS HIGHS ONLY IN THE SINGLE DIGITS MTNS TO L/M TEEN
VALLEYS. HAVE UNCUT SUPERBLEND BY SEVERAL DEGREES FOR HIGHS...BUT
KEPT CLOSE WITH LOWS RANGING FROM -10F TO +10F...AND HIGHLY
VARIABLE BASED ON CLOUDS/WINDS. SLIGHTLY WARMER TEMPS ARE
ANTICIPATED FOR MONDAY NIGHT INTO TUESDAY...BEFORE ADDITIONAL
COOLING ARRIVES BY THE MID OF NEXT WEEK. OVERALL....TEMPS WL
REMAIN 10 TO 20 DEGREES BLW NORMAL THRU THE PERIOD.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 06Z THURSDAY...AVIATION CHALLENGE WL BE TIMING OF ARCTIC
BOUNDARY THIS MORNING AND ASSOCIATED SNOW SHOWERS AND POTENTIAL
SNOW SQUALL. CRNT SFC ANALYSIS SHOWS COLD FRNT APPROACHING THE
OTTAWA VALLEY AND EXTENDING SOUTH ACRS CENTRAL LAKE ONTARIO...WITH
A NARROW BAND OF ENHANCED SNOW SHOWER ACTIVITY WITH VIS <1/2SM.
USING THE DISTANCE TIME TOOL IN AWIPS AND LATEST HRRR/RAP DATA
SHOWS THIS BAND IMPACTING MSS BTWN 09Z-10Z...SLK BTWN 10-12Z...AND
INTO THE CPV BY 12Z. A BRIEF 20 TO 30 MINUTE WINDOW OF IFR/LIFR
CONDITIONS WITH VIS BLW 1SM IN SNOW SHOWERS WL OCCUR...ALONG WITH
A WIND SHIFT TO THE WEST...ESPECIALLY AT MSS. THINKING IFR
CONDITIONS ASSOCIATED WITH BOUNDARY WL OCCUR AFT 12Z AT BTV/MPV
AND RUTLAND. IN ADDITION...THE COMBINATION OF UPSLOPE FLW AND SOME
WEAK LAKE ENHANCED MOISTURE WL CONT TO PRODUCE ON AND OFF IFR VIS
IN LIGHT SNOW THRU 12Z THIS MORNING AT SLK. ALSO...CANNOT RULE OUT
POTENTIAL FOR -SHSN AT MPV WITH BRIEF PERIODS OF IFR/MVFR
CONDITIONS BEFORE FROPA THIS MORNING. SOUNDINGS SUPPORT GUSTY
WEST/NORTHWEST WINDS OF 10 TO 15 KNOTS WITH GUSTS 25 TO 30 KNOTS
DEVELOPING BEHIND FROPA TODAY BTWN 12Z-22Z TODAY. THESE WINDS WL
SLOWLY DISSIPATE BY SUNSET THIS EVENING.
OUTLOOK 06Z THURSDAY THROUGH SUNDAY...
MAINLY VFR CONDITIONS BTWN 06Z AND 12Z THURSDAY...BEFORE NEXT
CLIPPER SYSTEM WITH SNOW SHOWERS AND IFR/MVFR CONDITIONS DEVELOP
BTWN 15Z AND 21Z THURS. A BRIEF SNOW SQUALL WL ONCE AGAIN BE
POSSIBLE ON THURS ASSOCIATED WITH NEXT SURGE OF ARCTIC AIR.
LINGERING UPSLOPE MTN SNOW SHOWERS WL PREVAIL AT SLK/MPV INTO
EARLY FRIDAY MORNING WITH PERIODS OF IFR/MVFR POSSIBLE...ALONG
WITH GUSTY WEST/NORTHWEST WINDS. SFC HIGH PRES WITH VFR CONDITIONS
DEVELOP FRIDAY INTO SATURDAY...BEFORE NEXT SYSTEM ARRIVES ON SAT
AFTN INTO SUNDAY WITH ADDITIONAL LIGHT SNOW SHOWERS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
314 AM CST WED FEB 26 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CST WED FEB 26 2014
THERE ARE SEVERAL CONCERNS IN THE SHORT TERM PERIOD INCLUDING THE
WIND CHILL ADVISORY THIS MORNING...FOLLOWED BY WINDS FROM MID
MORNING INTO THE AFTERNOON.
EARLY MORNING SURFACE ANALYSIS PLACED HIGH PRESSURE FROM SOUTHERN
NORTH DAKOTA SOUTHWARD INTO THE CENTRAL PLAINS. A COLD FRONT IS
EXPECTED TO MOVE ACROSS THE FORECAST AREA TODAY...BRINGING AN
INCREASE IN NORTHWEST WINDS AS THE FRONT PASSES.
FIRST REGARDING THE WIND CHILL ADVISORY...THE HEADLINE LOOKS TO BE
WELL PLACED. WIND CHILLS SOUTH AND WEST OF THE MISSOURI RIVER HAVE
GENERALLY REMAINED WARMER THAN ADVISORY LEVELS DUE IN PART TO WEAKER
WINDS IN PROXIMITY TO THE SURFACE RIDGE AXIS. WILL LEAVE THE WIND
CHILL ADVISORY IN ITS CURRENT CONFIGURATION SINCE AREAS NORTH AND
EAST OF THE MISSOURI RIVER CONTINUE TO SEE WIND CHILLS OF 25 TO 35
BELOW.
WINDS SPEEDS WILL BE THE NEXT CONCERN AS LOW LEVEL COLD AIR
ADVECTION TAKES HOLD BEHIND THE COLD FRONT. THE STRONGEST
PRESSURE RISE / FALL COUPLET IS ACROSS MINNESOTA INTO EASTERN NORTH
DAKOTA...BUT CLIPS THE EASTERN PART OF THE FORECAST AREA. LOW
LEVEL LAPSE RATES ALSO BECOME STEEPEST FROM THE JAMES RIVER VALLEY
AND EAST. MOMENTUM TRANSFER FROM RAP BUFR SOUNDINGS SUGGEST AREAS
OUTSIDE OF THE ADVISORY COULD BRIEFLY APPROACH ADVISORY
LEVELS...BUT THAT APPEARS SHORT LIVED AND THINK THE HEART OF THE
STRONGEST WINDS SHOULD BE IN THE EASTERN PART OF THE FORECAST
AREA. WILL ONLY MAKE A SMALL ADJUSTMENT TO THE WIND ADVISORY BY
ADDING DICKEY COUNTY WHICH LINES UP WELL WITH SURROUNDING OFFICES.
WILL CONTINUE TO MENTION THE POSSIBILITY OF BLOWING SNOW AND
REDUCED VISIBILITIES...BUT DO NOT THINK VISIBILITIES SHOULD FALL TO
1/2SM OR BELOW...SO DID NOT GO WITH A WINTER WEATHER ADVISORY.
IT WILL BE COLD AGAIN TONIGHT WITH WIND CHILLS AGAIN POTENTIALLY
FALLING TO ADVISORY LEVELS NORTH AND EAST OF THE MISSOURI RIVER.
WITH MULTIPLE HEADLINES ALREADY IN PLACE...DID NOT PUT OUT A
HEADLINE FOR THE WIND CHILLS TONIGHT...BUT EXPECT LATER SHIFTS
WILL HAVE TO CONSIDER THAT POSSIBILITY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 314 AM CST WED FEB 26 2014
WELL BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE EXTENDED
WITH SNOW CHANCES STILL ON TAP FOR THIS WEEKEND.
SOUTHERLY RETURN FLOW WILL INCREASE THURSDAY AHEAD OF AN
APPROACHING COLD FRONT. NOT MUCH IN THE WAY OF WARM AIR ADVECTION
IS FORECAST WITH HIGHS FROM AROUND ZERO EAST TO THE LOW TEENS
WEST. THE COLD FRONT WILL PUSH THROUGH THE STATE FRIDAY MORNING
WITH BREEZY CONDITIONS EXPECTED TO DEVELOP IN ITS WAKE. THE MEDIUM
RANGE MODELS MAINTAIN A DRY FROPA.
WITH THE SURGE OF ARCTIC AIR...A BAROCLINIC ZONE IS STILL PROGGED
TO SET UP OVER SOUTHWESTERN NORTH DAKOTA FRIDAY AFTERNOON/NIGHT.
THIS SHOULD PROVIDE ENOUGH ELEVATED CONVERGENCE TO GENERATE A
CHANCE OF SNOW SOUTHWEST LATE FRIDAY INTO SATURDAY.
THE MEDIUM RANGE MODELS BEGIN TO DIVERGE WITH RESPECT TO THE
SYNOPTIC PATTERN OVER THE NORTHERN PLAINS SUNDAY THROUGH THE END
OF THE PERIOD. THE LATEST GFS IS DEEPER AND MORE PROGRESSIVE WITH
AN UPPER LOW OVER THE CANADIAN ROCKIES SATURDAY MOVING THROUGH THE
NORTHERN PLAINS SUNDAY. HOWEVER...THE LATEST ECMWF PINCHES OFF THE
UPPER LOW OVER THE CANADIAN ROCKIES WHERE IT BECOMES STATIONARY
THROUGH THE END OF THE PERIOD. GIVEN THE MODEL TO MODEL AND RUN TO
RUN INCONSISTENCIES...FORECAST A BLEND OF SOLUTIONS WITH SNOW
CHANCES SUNDAY...AND DRY CONDITIONS OVER WESTERN AND CENTRAL NORTH
DAKOTA MONDAY AND TUESDAY. REGARDLESS OF WHICH SOLUTION
VERIFIES...WELL BELOW TEMPERATURES ARE STILL FORECAST THROUGH THE
END OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 314 AM CST WED FEB 26 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD. THE MAIN
CONCERN WILL BE INCREASING WINDS AS NORTHWEST WINDS INCREASE BY
MID MORNING WEDNESDAY AND CONTINUE INTO THE AFTERNOON. CURRENTLY
IT LOOKS LIKE THE STRONGEST WINDS WILL PREVAIL FROM KMOT-
KJMS...THOUGH ALL LOCATIONS WILL SEE WINDS BECOME GUSTY. HELD ONTO
THE 6SM IN BLSN FOR KMOT AND KJMS ONCE THE WINDS INCREASE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR NDZ001>005-
009>013-021>023-025-035>037-046>048-050-051.
WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR NDZ004-005-012-013-022-023-025-037-048-051.
&&
$$
SHORT TERM...CK
LONG TERM...TM
AVIATION...CK
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1246 AM CST WED FEB 26 2014
.UPDATE...
HAVE ISSUED A DENSE FOG ADVISORY FOR COASTAL COUNTIES. NEW ZONES
OUT SHORTLY. 23
&&
.PREV DISCUSSION... /ISSUED 1147 PM CST TUE FEB 25 2014/
DISCUSSION...
06Z AVIATION DISCUSSION BELOW.
AVIATION...
PREVIOUS 00Z THINKING STILL HOLDS TRUE WITH THIS LATEST SET OF
TAFS. THAT BEING OF PRIMARILY VLIFR TO IFR DECKS WITH PERIODIC
SHOWERS AND STRENGTHENED NORTHERLIES...ANOTHER ROUND OR TWO OF
HIGHER AREAL PRECIPITATION COVERAGE IN THE PREDAWN HOURS AND LATER
WEDNESDAY AFTERNOON FROM THE PASSAGE OF WEAK WESTERLY IMPULSES. IN
BETWEEN THESE SHORTWAVES...A POST-FRONTAL ENVIRONMENT CONDUCIVE
TO THE DEVELOPMENT OF EITHER LIGHT RAIN/DRIZZLE/MIST AT THE TERMINAL
TO PASSING VICINITY SHOWERS WITHIN 10 NM OF MOST REGIONAL HUBS.
JUST KEPT IT RAIN THROUGH TOMORROW EVENING...WITH ANY CONVECTION
REMAINING ELEVATED...PER THE COOLING SURFACE AND WARMER ALOFT
PROFILES BROUGHT ON BY THE LOWER LEVEL COLD AIR ADVECTION. 31
PREV DISCUSSION... /ISSUED 930 PM CST TUE FEB 25 2014/
DISCUSSION...
CURRENT FORECAST IS IN GOOD SHAPE. NO UPDATE IS PLANNED FOR THE
OVERNIGHT HOURS. WILL WAIT FOR ALL OF THE 00Z MODELS TO ARRIVE
BEFORE ANY SIGNIFICANT CHANGES ARE MADE TO OUR RAIN CHANCES...WINDS
AND TEMPERATURES.
COLD FRONT IS SLOWLY WORKING ITS WAY THROUGH SOUTHEAST TEXAS THIS
EVENING...APPROACHING THE I-10 CORRIDOR AT AROUND 9 PM. AREAS OF
RAIN WITH EMBEDDED SHOWERS AND THUNDERSTORMS ARE DEVELOPING ACROSS
THE AREA...AND MODELS INDICATE THIS SHOULD CONTINUE OVERNIGHT AND
ON INTO TOMORROW MORNING (SOME SPOTS WITH THE HEAVIER STORMS HAVE
ALREADY RECEIVED 1 TO 2 INCHES). TEMPERATURES ARE IN THE LOW TO
MID 50S BEHIND THE FRONT UP NORTH...AND EXPECT THIS COOLER AIR TO
WORK ITS WAY TOWARD THE COAST OVERNIGHT. 42
PREV DISCUSSION... /ISSUED 609 PM CST TUE FEB 25 2014/
DISCUSSION...
00Z AVIATION DISCUSSION BELOW.
AVIATION...
THE SHORT TERM FORECAST...OR THROUGH THE EARLY WEDNESDAY MORNING
HOURS...WILL BE FOR INTERMITTENT SHOWERS WITH A ISOLATED STORM
AND STRENGTHENED NORTH WIND BEHIND AN EVENING COLD FRONTAL PASSAGE.
THE MAIN IMPULSE DRIVING THIS ONGOING WIDELY SCATTERED -SHRA (ISO
-TSRA) IS TRAVELING ACROSS NORTHERN TEXAS THIS EVENING WITH THE
ONLY TRIGGERS LEFT OVER IN THIS HIGHLY-MOIST ENVIRONMENT FOR
REPEAT PRECIPITATION BEING ANOTHER EASTERN PASSING SHORTWAVE
RIPPLE WITHIN THE WESTERLY FLOW AND/OR THE ENHANCED POST-FRONTAL
ISENTROPIC UPGLIDE AS SOUTHWESTERLY MID-UPPER FLOW RIDES UP AND
OVER A PUMPED UP NORTH-NORTHEAST LOWER LEVEL WIND. BETTER UPPER
DIFFULENCE BY TOMORROW AFTERNOON AS SE TX FALLS UNDER AN EXITING
RRQ JET. CONSIDERING THE ABOVE ELEMENTS AND...EVEN WITH NWP
MODELING NOT PROVIDING MUCH GUIDANCE UP TO NOW...STILL BELIEVE
THAT ALL WILL COME IN-LINE FOR BETTER OVERALL (LIGHT) RAIN
COVERAGE. PROBABLY NOT AN ALL-DAY RAIN EVENT...BUT GT 50% OF THE
TIME THERE WILL BE THAT PASSING SHOWER...BRIEF MODERATE RAINFALL
ASSOCIATED WITH STRONGER CELLS WEDNESDAY AFTERNOON...BUT THERE
WILL ALSO BE LONGER PERIODS OF A JUST A LIGHT MIST AND/OR DRIZZLE
ALONG WITH THOSE PESKY FLUCTUATING DECKS FROM IFR TO MVFR AND VICE
VERSA. 31
PREV DISCUSSION... /ISSUED 333 PM CST TUE FEB 25 2014/
DISCUSSION...
FRONT IS NOW PUSHING INTO NRN PORTIONS OF SE TX. SHOULD BE BETWEEN
I-10 AND THE COAST AROUND MIDNIGHT AND OFF THE BEACHES BY 4AM
(EFFECTIVELY ENDING SEA FOG ISSUES FOR A FEW DAYS). STARTING TO
SEE SOME SCT PRECIP DEVELOP ACROSS S PARTS OF THE AREA AND EXPECT
IT TO GRADUALLY INCREASE IN COVERAGE AHEAD OF, AND ESPECIALLY
BEHIND, THE FRONT. HRRR MODEL AND TO A DEGREE NAM12 HAS DONE
FAIRLY WELL WITH RAINFALL DEPICTION (OR LACK THEREOF) SO FAR TODAY
AND SHORT TERM FCST WAS TRENDED THAT WAY. GFS/ECMWF HAVE BEEN
HORRIBLY OVERDONE BOTH IN COVERAGE & AMOUNTS UP TO THIS TIME.
PERIODS OF PRECIP WILL LIKELY CONTINUE THRU WED IN ASSOCIATION
WITH H85 FRONT AND UPPER IMPULSES RIDING FURTHER OVERHEAD IN THE
WRLY FLOW ALOFT. CONSIDERING STRONG CAA...CLOUDINESS AND PRECIP
THE HIGHS FOR THE 24 HOUR PERIOD WILL OCCUR AROUND MIDNIGHT
FOLLOWED BY FALLING AND/OR STEADY TEMPS IN THE 40S WED. RAIN
SHOULD TAPER OFF WED EVENING.
COOL WX CONTINUES THURS BUT ONSHORE WIND WILL BE RESUMING AS HIGH
PRES MOVES EAST AND NEXT SHORTWAVE STARTS DIGGING SEWD DOWN THE
4-CORNERS AREA. THIS DISTURBANCE ISN`T AS IMPRESSIVE AS PREVIOUS
DAYS AND DON`T ANTICIPATE MUCH OF AN IMPACT HERE AS IT MOVES ALONG
THE RED RIVER FRIDAY...AS BEST ENERGY WILL BE WELL NORTH AND A
CAP SHOULD BE IN PLACE. FURTHER LOWERED POPS.
WARMING TREND CONTINUES THRU THE WEEKEND WITH ONSHORE FLOW IN
PLACE. APPEARS THAT WE`LL PROBABLY HAVE ANOTHER COASTAL FOG EVENT
BUT LOOKS LIKE MARDI GRAS PARADES SHOULD OTHERWISE BE DRY PRIOR TO
MID TO LATE SUNDAY AFTN. NEXT STORM SYSTEM APPROACHES FROM THE
WEST LATE IN THE WEEKEND AND KEPT 20-40% POPS IN PLACE SUN AFTN/NIGHT
AHEAD OF THE NEXT FRONT THAT`LL BE MOVING THRU SUNDAY NIGHT OR
MONDAY. KNOCKED TEMPS DOWN EARLY NEXT WEEK (MAYBE NOT ENOUGH) AS
1040+MB HIGH DROPS INTO THE PLAINS. 47
MARINE...
SEA FOG WILL CONTINUE OVER THE GULF WATERS THIS AFTERNOON. AM
EXPECTING THE FOG TO REDEVELOP AND BECOME DENSE OVER THE BAYS LATER
THIS AFTERNOON AND EVENING. THE FOG WILL CLEAR OUT BETWEEN MIDNIGHT
AND SUNRISE AS A COLD FRONT PUSHES THROUGH THE BAYS AND OFF THE
COAST. THE MODELS HAVE BEEN FAIRLY CONSISTENT THE PAST FEW DAYS AND
AM FAIRLY CONFIDENT ON THE TIMING. EXPECT THE FRONT TO MOVE THROUGH
THE BAYS BY AROUND 3 AM AND THEN BEYOND 20 NM OFFSHORE BY 4 AM. THE
12Z MODEL RUN AND GUIDANCE FROM THIS MORNING FORECASTED SLIGHTLY
HIGHER WINDS...INDICATING THAT SMALL CRAFT ADVISORIES ARE LIKELY FOR
THE GULF WATERS AND MATAGORDA BAY. WOULD NOT BE SURPRISED IF WINDS
INCREASE TO BETWEEN 20 AND 25 KNOTS FOR AT LEAST MOST OF THE LOWER
PART OF GALVESTON BAY...ALSO. EXPECT THE NORTHEASTERLY WINDS TO
DIMINISH WEDNESDAY NIGHT AND THURSDAY. ANOTHER FOG EVENT MAY DEVELOP
BY LATE THIS WEEK AS ONSHORE REDEVELOPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 33 57 42 70 / 60 20 10 10 10
HOUSTON (IAH) 49 36 59 43 69 / 70 30 10 10 10
GALVESTON (GLS) 54 42 55 53 66 / 60 40 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 4 AM CST EARLY THIS MORNING FOR THE
FOLLOWING ZONES: BRAZORIA...CHAMBERS...GALVESTON...
MATAGORDA.
GM...DENSE FOG ADVISORY UNTIL 4 AM CST EARLY THIS MORNING FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS
FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60
NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT
20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO NOON CST TODAY
FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM NOON CST TODAY THROUGH
THIS AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
MATAGORDA BAY.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 6 PM CST THIS
EVENING FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM THIS EVENING THROUGH
LATE TONIGHT FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO MIDNIGHT CST
TONIGHT FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
HIGH ISLAND TO FREEPORT 20 TO 60 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION LATE TONIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...23
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1147 PM CST TUE FEB 25 2014
.DISCUSSION...
06Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
PREVIOUS 00Z THINKING STILL HOLDS TRUE WITH THIS LATEST SET OF
TAFS. THAT BEING OF PRIMARILY VLIFR TO IFR DECKS WITH PERIODIC
SHOWERS AND STRENGTHENED NORTHERLIES...ANOTHER ROUND OR TWO OF
HIGHER AREAL PRECIPITATION COVERAGE IN THE PREDAWN HOURS AND LATER
WEDNESDAY AFTERNOON FROM THE PASSAGE OF WEAK WESTERLY IMPULSES. IN
BETWEEN THESE SHORTWAVES...A POST-FRONTAL ENVIRONMENT CONDUCIVE
TO THE DEVELOPMENT OF EITHER LIGHT RAIN/DRIZZLE/MIST AT THE TERMINAL
TO PASSING VICINITY SHOWERS WITHIN 10 NM OF MOST REGIONAL HUBS.
JUST KEPT IT RAIN THROUGH TOMORROW EVENING...WITH ANY CONVECTION
REMAINING ELEVATED...PER THE COOLING SURFACE AND WARMER ALOFT
PROFILES BROUGHT ON BY THE LOWER LEVEL COLD AIR ADVECTION. 31
&&
.PREV DISCUSSION... /ISSUED 930 PM CST TUE FEB 25 2014/
DISCUSSION...
CURRENT FORECAST IS IN GOOD SHAPE. NO UPDATE IS PLANNED FOR THE
OVERNIGHT HOURS. WILL WAIT FOR ALL OF THE 00Z MODELS TO ARRIVE
BEFORE ANY SIGNIFICANT CHANGES ARE MADE TO OUR RAIN CHANCES...WINDS
AND TEMPERATURES.
COLD FRONT IS SLOWLY WORKING ITS WAY THROUGH SOUTHEAST TEXAS THIS
EVENING...APPROACHING THE I-10 CORRIDOR AT AROUND 9 PM. AREAS OF
RAIN WITH EMBEDDED SHOWERS AND THUNDERSTORMS ARE DEVELOPING ACROSS
THE AREA...AND MODELS INDICATE THIS SHOULD CONTINUE OVERNIGHT AND
ON INTO TOMORROW MORNING (SOME SPOTS WITH THE HEAVIER STORMS HAVE
ALREADY RECEIVED 1 TO 2 INCHES). TEMPERATURES ARE IN THE LOW TO
MID 50S BEHIND THE FRONT UP NORTH...AND EXPECT THIS COOLER AIR TO
WORK ITS WAY TOWARD THE COAST OVERNIGHT. 42
&&
PREV DISCUSSION... /ISSUED 609 PM CST TUE FEB 25 2014/
DISCUSSION...
00Z AVIATION DISCUSSION BELOW.
AVIATION...
THE SHORT TERM FORECAST...OR THROUGH THE EARLY WEDNESDAY MORNING
HOURS...WILL BE FOR INTERMITTENT SHOWERS WITH A ISOLATED STORM
AND STRENGTHENED NORTH WIND BEHIND AN EVENING COLD FRONTAL PASSAGE.
THE MAIN IMPULSE DRIVING THIS ONGOING WIDELY SCATTERED -SHRA (ISO
-TSRA) IS TRAVELING ACROSS NORTHERN TEXAS THIS EVENING WITH THE
ONLY TRIGGERS LEFT OVER IN THIS HIGHLY-MOIST ENVIRONMENT FOR
REPEAT PRECIPITATION BEING ANOTHER EASTERN PASSING SHORTWAVE
RIPPLE WITHIN THE WESTERLY FLOW AND/OR THE ENHANCED POST-FRONTAL
ISENTROPIC UPGLIDE AS SOUTHWESTERLY MID-UPPER FLOW RIDES UP AND
OVER A PUMPED UP NORTH-NORTHEAST LOWER LEVEL WIND. BETTER UPPER
DIFFULENCE BY TOMORROW AFTERNOON AS SE TX FALLS UNDER AN EXITING
RRQ JET. CONSIDERING THE ABOVE ELEMENTS AND...EVEN WITH NWP
MODELING NOT PROVIDING MUCH GUIDANCE UP TO NOW...STILL BELIEVE
THAT ALL WILL COME IN-LINE FOR BETTER OVERALL (LIGHT) RAIN
COVERAGE. PROBABLY NOT AN ALL-DAY RAIN EVENT...BUT GT 50% OF THE
TIME THERE WILL BE THAT PASSING SHOWER...BRIEF MODERATE RAINFALL
ASSOCIATED WITH STRONGER CELLS WEDNESDAY AFTERNOON...BUT THERE
WILL ALSO BE LONGER PERIODS OF A JUST A LIGHT MIST AND/OR DRIZZLE
ALONG WITH THOSE PESKY FLUCTUATING DECKS FROM IFR TO MVFR AND VICE
VERSA. 31
PREV DISCUSSION... /ISSUED 333 PM CST TUE FEB 25 2014/
DISCUSSION...
FRONT IS NOW PUSHING INTO NRN PORTIONS OF SE TX. SHOULD BE BETWEEN
I-10 AND THE COAST AROUND MIDNIGHT AND OFF THE BEACHES BY 4AM
(EFFECTIVELY ENDING SEA FOG ISSUES FOR A FEW DAYS). STARTING TO
SEE SOME SCT PRECIP DEVELOP ACROSS S PARTS OF THE AREA AND EXPECT
IT TO GRADUALLY INCREASE IN COVERAGE AHEAD OF, AND ESPECIALLY
BEHIND, THE FRONT. HRRR MODEL AND TO A DEGREE NAM12 HAS DONE
FAIRLY WELL WITH RAINFALL DEPICTION (OR LACK THEREOF) SO FAR TODAY
AND SHORT TERM FCST WAS TRENDED THAT WAY. GFS/ECMWF HAVE BEEN
HORRIBLY OVERDONE BOTH IN COVERAGE & AMOUNTS UP TO THIS TIME.
PERIODS OF PRECIP WILL LIKELY CONTINUE THRU WED IN ASSOCIATION
WITH H85 FRONT AND UPPER IMPULSES RIDING FURTHER OVERHEAD IN THE
WRLY FLOW ALOFT. CONSIDERING STRONG CAA...CLOUDINESS AND PRECIP
THE HIGHS FOR THE 24 HOUR PERIOD WILL OCCUR AROUND MIDNIGHT
FOLLOWED BY FALLING AND/OR STEADY TEMPS IN THE 40S WED. RAIN
SHOULD TAPER OFF WED EVENING.
COOL WX CONTINUES THURS BUT ONSHORE WIND WILL BE RESUMING AS HIGH
PRES MOVES EAST AND NEXT SHORTWAVE STARTS DIGGING SEWD DOWN THE
4-CORNERS AREA. THIS DISTURBANCE ISN`T AS IMPRESSIVE AS PREVIOUS
DAYS AND DON`T ANTICIPATE MUCH OF AN IMPACT HERE AS IT MOVES ALONG
THE RED RIVER FRIDAY...AS BEST ENERGY WILL BE WELL NORTH AND A
CAP SHOULD BE IN PLACE. FURTHER LOWERED POPS.
WARMING TREND CONTINUES THRU THE WEEKEND WITH ONSHORE FLOW IN
PLACE. APPEARS THAT WE`LL PROBABLY HAVE ANOTHER COASTAL FOG EVENT
BUT LOOKS LIKE MARDI GRAS PARADES SHOULD OTHERWISE BE DRY PRIOR TO
MID TO LATE SUNDAY AFTN. NEXT STORM SYSTEM APPROACHES FROM THE
WEST LATE IN THE WEEKEND AND KEPT 20-40% POPS IN PLACE SUN AFTN/NIGHT
AHEAD OF THE NEXT FRONT THAT`LL BE MOVING THRU SUNDAY NIGHT OR
MONDAY. KNOCKED TEMPS DOWN EARLY NEXT WEEK (MAYBE NOT ENOUGH) AS
1040+MB HIGH DROPS INTO THE PLAINS. 47
MARINE...
SEA FOG WILL CONTINUE OVER THE GULF WATERS THIS AFTERNOON. AM
EXPECTING THE FOG TO REDEVELOP AND BECOME DENSE OVER THE BAYS LATER
THIS AFTERNOON AND EVENING. THE FOG WILL CLEAR OUT BETWEEN MIDNIGHT
AND SUNRISE AS A COLD FRONT PUSHES THROUGH THE BAYS AND OFF THE
COAST. THE MODELS HAVE BEEN FAIRLY CONSISTENT THE PAST FEW DAYS AND
AM FAIRLY CONFIDENT ON THE TIMING. EXPECT THE FRONT TO MOVE THROUGH
THE BAYS BY AROUND 3 AM AND THEN BEYOND 20 NM OFFSHORE BY 4 AM. THE
12Z MODEL RUN AND GUIDANCE FROM THIS MORNING FORECASTED SLIGHTLY
HIGHER WINDS...INDICATING THAT SMALL CRAFT ADVISORIES ARE LIKELY FOR
THE GULF WATERS AND MATAGORDA BAY. WOULD NOT BE SURPRISED IF WINDS
INCREASE TO BETWEEN 20 AND 25 KNOTS FOR AT LEAST MOST OF THE LOWER
PART OF GALVESTON BAY...ALSO. EXPECT THE NORTHEASTERLY WINDS TO
DIMINISH WEDNESDAY NIGHT AND THURSDAY. ANOTHER FOG EVENT MAY DEVELOP
BY LATE THIS WEEK AS ONSHORE REDEVELOPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 43 43 33 57 42 / 70 60 20 10 10
HOUSTON (IAH) 49 49 36 59 43 / 70 70 30 10 10
GALVESTON (GLS) 54 54 42 55 53 / 70 60 40 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 4 AM CST WEDNESDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 6 AM TO NOON CST WEDNESDAY FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT SHOULD EXERCISE CAUTION WEDNESDAY AFTERNOON FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM CST WEDNESDAY FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM WEDNESDAY EVENING
THROUGH LATE WEDNESDAY NIGHT FOR THE FOLLOWING ZONES:
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20
NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 6 AM WEDNESDAY TO MIDNIGHT CST
WEDNESDAY NIGHT FOR THE FOLLOWING ZONES: WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...
WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION LATE WEDNESDAY NIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...31
AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
936 AM EST Wed Feb 26 2014
.Update...The 12z KTAE sounding was nearly saturated up to 600mb
with deep west to southwest flow. The cold front as of 14z has
already advanced into SW GA and the Florida panhandle. Most
locations have already reached the max temp for today and temps
will either remain steady or slowly fall through this afternoon.
Rain continues to be widespread and PoPs were untouched. Thus far,
SCT TSTMS have stayed offshore so mention of TSTMS were removed
for all but the coastal areas and SE Big Bend.
.Prev Discussion [411 AM EST]...
.Near Term [Through Today]...
At 09z, a surface cold front extended from a weak low in SC,
southwest to near Albany GA, to near Destin FL, and then along much
of the rest of the LA-TX Gulf coast. Regional radars showed a fairly
large area of rain along and to the north of the surface cold front
from near the AL-GA state line westward to SE TX. The placement of
the rain relative to the surface front was suggestive of an anafront
structure, with rearward sloping ascent along the cold front through
the vertical. This is confirmed by WSW flow on area radar VWPs in
the 900-700mb layer, and from a glance at RAP isentropic charts.
Given the isentropic ascent in the lowest levels of the troposphere,
but a general lack of significant forcing aloft, it`s likely that
rain will continue to be forced in a shallow layer just above the
surface through the remainder of the day. Models are in fairly good
agreement on the timing of the best isentropic ascent and QPF. We
leaned towards the consensus of recent local and NCEP WRF runs. With
widespread rain expected, PoPs were raised to 100% for today pretty
much everywhere across the forecast area. The rain should be most
widespread (and heaviest) in the morning, with it tapering off and
clearing from NW-SE in the afternoon and early evening.
Looking at GOES blended precipitable water product, there is a large
plume of PWATS >150% of normal extending from the western parts of
our forecast area west into Texas. This deeper moisture will
continue to advect into the area today, and could support some
locally heavier rain. This will be especially true near the Gulf
coast - closer to the surface cold front as the strongest forcing
for ascent arrives this morning after sunrise. Maximum QPF from
convection allowing models (CAM) is focused around Gulf and Franklin
counties and is on the order of 2-3 inches. With the heaviest rain
likely to fall in the lower portions of river basins, and average
rainfall generally between 0.50 and 1.00 inches, we don`t anticipate
any significant flooding issues. Instability should be limited
enough to only support some general thunderstorms - updrafts should
be too weak to pose much of a severe weather concern.
&&
.Prev Discussion [411 AM EST]...
.Short Term [Tonight Through Friday]...
Rain will taper off from north to south this evening, but may not
clear completely from our Southeast FL Big Bend zones until Thursday
morning. As skies clear behind the rain, temps will tumble into the
30s except for coastal and southeastern sections of the Big Bend. A
light freeze is forecast along and north of an Albany to Dothan to
Crestview line. Maximum freeze durations in Coffee County AL will be
about 5 hours. Max temps will be about 10 degrees below normal on
Thursday and range from the mid 50s far northwest to Around 60
southeast. This will set the stage for a widespread light freeze
Thursday night that will impact most inland areas. Coastal locations
will hold at 40. Temps will moderate to within a few degrees of
normal on Friday with max temps ranging from the lower 60s north to
the mid to upper 60s southeast.
.Long Term [Friday Night Through Wednesday]...
On Friday NIGHT, a shortwave will be moving across the Mid
Atlantic states. Further to the west, a disturbance will be moving
onshore into central California. A vort max located over the Rockies
will propagate eastward in zonal flow bringing slight PoP chances
on Saturday, however this forcing appears to be weak and displaced
more to the north of our CWA. From here on the GFS and Euro really
diverge in their handling of the upcoming pattern. The GFS is more
aggressive in phasing a shortwave over western Mexico with a
shortwave rounding the base of a trough over Idaho. This combination
pushes a surface front through our area late Monday night into
Tuesday but quickly exits the area. The Euro meanwhile remains
less amplified keeping the flow aloft more zonal and bringing a
series of vort maxes through the area early next week. This will
cause a stalling of a surface front over our CWA, and with each
passing upper-level vort max another round of rain. Both agree
that Tuesday morning should be pretty wet but given the
uncertainty with which this front will exit we have tentatively
gone with 40 PoPs for Tuesday afternoon.
.Aviation...
[Through 12Z Thursday] We expect IFR CIGS at all terminals today
along with periods of mostly -RA. Some +RA with TS will be possible
closer to the Gulf coast, particularly at ECP and TLH. Some of the
+RA could reduce visibilities to around 1-3SM at times. Rain will
gradually clear out in the afternoon from NW-SE, with CIGS
gradually lifting through MVFR to VFR range by the evening and
continuing overnight.
.Marine...
A cold front will slip south across the waters today shifting winds
to offshore. Wind speeds behind the front will reach marginal small
craft advisory criteria across the western legs by midday. Advisory
conditions will be possible across the eastern zones tonight. Winds
will then drop below cautionary levels by midday Thursday as high
pressure builds toward the waters. Winds will remain below headline
criteria through the weekend as they gradually veer to the east and
then southeast.
.Fire Weather...
Widespread wetting rains are expected today, which will leave fuel
moisture rather high on Thursday. Some of the finer (smaller) fuels
(measured by 10-hr fuel moisture) could dry out as a much drier air
mass arrives for Thursday, but should not be sufficiently dry in
Florida or Georgia to create red flag conditions. In southeast
Alabama, red flag criteria includes 4+ hr durations of RH < 25%.
This looks achievable, but the wet fuels would likely preclude any
sort of critical fire weather conditions. For now, we will maintain
the Fire Weather Watch. It`s possible durations could be met again
on Friday in southeast Alabama, and by then smaller fuels would have
likely dried more substantially.
.Hydrology...
Periods of moderate rain today and tonight across the forecast
area will result in slight to modest rises on area rivers. The
Choctawhatchee River at Bruce is forecast to crest right at flood
stage from Thursday into Saturday. The Apalachicola River at
Blountstown is at its crest and is forecast to fall below flood
stage Thursday evening. The Aucilla River at Lamont is forecast to
reach flood stage Thursday night and crest Friday night. Storm
total rainfall through Thursday morning is forecast to be less
than an inch north of I-10 with a maximum of near two inches over
coastal sections of Gulf and Franklin Counties. With the greatest
totals falling in the lower stretches of the river basins, rises
will be confined mainly to FL.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 60 39 60 29 65 / 100 50 10 0 0
Panama City 63 39 58 36 62 / 100 50 10 0 0
Dothan 54 31 57 31 62 / 100 30 0 0 0
Albany 55 32 58 29 62 / 100 20 0 0 0
Valdosta 59 37 59 30 64 / 100 50 0 0 0
Cross City 65 44 61 30 67 / 100 60 20 0 0
Apalachicola 64 41 58 35 61 / 100 60 10 0 0
&&
.TAE Watches/Warnings/Advisories...
FL...None.
GA...None.
AL...Fire Weather Watch from Thursday morning through Thursday
afternoon for Coffee-Dale-Geneva-Henry-Houston.
GM...Small Craft Advisory until 10 AM EST Thursday for Coastal waters
from Apalachicola to Destin FL out 20 NM-Waters from
Apalachicola to Destin FL from 20 to 60 NM.
&&
$$
UPDATE...BARRY
NEAR TERM...LAMERS
SHORT TERM...WOOL
LONG TERM...BARRY/WALSH
AVIATION...LAMERS/BARRY
MARINE...WOOL FIRE
WEATHER...LAMERS
HYDROLOGY...WOOL
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
952 AM EST WED FEB 26 2014
.SYNOPSIS...
A PROLONGED STRETCH OF COLD WEATHER...WITH TEMPERATURES RUNNING
10 TO 20 DEGREES BELOW AVERAGE...IS EXPECTED TO PERSIST THROUGH
EARLY NEXT WEEK. REINFORCING ARCTIC FRONTS MOVING FROM WEST TO
EAST ACROSS THE NORTH COUNTRY THIS MORNING AND AGAIN DURING THE
MIDDAY THROUGH AFTERNOON HOURS THURSDAY WILL BRING SCATTERED SNOW
SHOWERS AND SNOW SQUALLS. A QUICK DUSTING TO A COUPLE INCHES OF
SNOW IS POSSIBLE WITH THESE FRONTAL PASSAGES...ALONG WITH BRIEF
PERIODS OF VERY LOW VISIBILITY. HIGH TEMPERATURES TODAY WILL
RANGE FROM THE MID TEENS TO LOWER 20S...AND DEVELOPING WESTERLY
WINDS OF 15 TO 25 MPH WILL RESULT IN WIND CHILL VALUES NEAR ZERO.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 928 AM EST WEDNESDAY...SNOW SQUALL ACTIVITY CURRENTLY
MOVING ACROSS THE NORTHERN CHAMPLAIN VALLEY. THINK THAT CURRENT
FORECAST IS IN GOOD SHAPE SO DID NOT ALTER POPS OR WX AT ALL.
THIS AREA OF SQUALLS WILL PUSH EASTWARD ACROSS VERMONT OVER THE
NEXT FEW HOURS AND THEN POPS DECREASE LATE THIS AFTERNOON AND
EVENING. PREVIOUS DISCUSSION FOLLOWS.
SNOW SHOWER ACTIVITY HAS LOST ORGANIZATION AND STRUCTURE 10-12Z
AS IT MOVED AWAY FROM THE LAKE INDUCED INSTABILITY NEAR LAKE
ONTARIO AND AS FRONTOGENETIC CIRCULATION HAS BEEN DISRUPTED BY
THE STEEP TERRAIN OF THE ADIRONDACKS. EXPECTATION - CONSISTENT
WITH 11Z RAP - IS THAT LIGHT SNOW SHOWERS WILL SHIFT THRU THE
CHAMPLAIN VALLEY NEXT 1-3 HOURS...AND THEN SHOW AN INCREASE IN
INTENSITY ACROSS CENTRAL AND ERN VT AFTER 15Z WITH DEVELOPMENT OF
STEEP LOW- LEVEL LAPSE RATES AND SBCAPE UP TO 100 J/KG. BEST
CHANCE FOR BRIEF MODERATE TO HEAVY SNOW WILL BE ACROSS THE CT
RIVER VALLEY BEFORE ACTIVITY SHIFTS EAST INTO NH. WE/LL SEE A
QUICK DUSTING TO 2" IN SPOTS...HIGHEST CENTRAL/ERN VT DURING THE
MIDDAY HRS. OTHERWISE...LOOKING AT CONTINUED COLD TEMPS WITH
HIGHS IN THE MID TO UPPER TEENS...EXCEPT LOW 20S IN FAR SERN
SECTIONS. INCREASED COLD ADVECTION THIS AFTN MAY ALLOW TEMPS TO
LEVEL OFF AFTER NOON EDT. STEEP LOW-LEVEL LAPSE RATES WILL
CONTRIBUTE TO GUSTY S-SW WINDS IN ADVANCE OF THE FRONT 15-25 MPH
WITH POST- FRONTAL GUSTS TO 30 MPH...SHIFTING INTO THE WEST
FOLLOWING FRONTAL PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 342 AM EST WEDNESDAY...SFC RIDGE BUILDS BRIEFLY ACROSS THE
AREA THIS EVENING AND OVERNIGHT...ALLOWING FOR DIMINISHING WIND
AND A PERIOD OF PARTIAL CLEARING. WITH ARCTIC AIR MASS IN PLACE
(850MB TEMPS -24C)...THE RADIATIONAL COOLING WILL RESULT IN COLD
OVERNIGHT LOWS RANGING FROM NEAR ZERO IN THE CHAMPLAIN VALLEY TO
AROUND 10 BELOW IN THE ADIRONDACKS AND NORTHEAST KINGDOM. TEMPS
MAY LEVEL OFF AFTER MIDNIGHT WITH SOME INCREASE IN CLOUDS IN
ADVANCE OF NEXT SYSTEM.
NEXT SHORTWAVE TROUGH ROTATING AROUND THE SRN PERIPHERY OF PARENT
UPPER LOW ANCHORED ACROSS JAMES BAY WILL TRANSLATE ACROSS THE ERN
GREAT LAKES AROUND 12Z THURSDAY...AND ACROSS THE NORTH COUNTRY
15-21Z TIME FRAME THURSDAY. THIS NEXT SHORTWAVE IS APPEARS
VIGOROUS IN WV IMAGERY AND IN NWP PROJECTIONS...SO QG ASCENT WILL
BE MODERATELY STRONG AS UPR TROUGH APPROACHES DURING THE DAY
THURSDAY. IT APPEARS SBCAPE VALUES WILL BE BETTER ACROSS MOST
SECTIONS OF THE NORTH COUNTRY WITH THIS SYSTEM TOMORROW (AS
OPPOSED TO THE WEAKER ONE TODAY)...WITH 06Z NAM INDICATING
100-150 J/KG ACROSS MUCH OF THE NORTH COUNTRY. ALSO INTERESTING
ARE PROGGED PBL HEIGHTS TO 600MB WITH STEEP LAPSE RATES FROM THE
SFC-12 KFT...A DEFAULT TROPOPAUSE IN THE ARCTIC AIR REGIME.
SO...GOOD CONVECTIVE SNOW POTENTIAL. FRONTOGENETIC FORCING IS NOT
AS WELL ORGANIZED AS WEDNESDAY...SO WOULD ANTICIPATE SMALLER LINE
SEGMENTS AND CONVECTIVE CELLS PRODUCING BRIEF BURSTS OF HEAVIER
SNOW SHOWERS AND POSSIBLE SQUALLS WITH GUSTS 30-35 MPH. A QUICK
1-3" IS POSSIBLE IN SPOTS...AND WILL AGAIN CAUSE SOME BRIEF
TRANSPORTATION HAZARD DUE TO LOW VSBY AND SNOW COVERED ROADS.
MADE MENTION OF THIS AS WELL IN THE MORNING HWO. HIGHS THURSDAY
IN THE UPR TEENS TO LOW 20S. SYSTEM MOVES EAST OF THE AREA
THURSDAY NIGHT WITH JUST A FEW LINGERING MTN FLURRIES. LOWS AGAIN
ZERO TO -10F...BUT LOCALLY COLDER IN THE NRN ADIRONDACKS IF
PARTIAL CLEARING CAN OCCUR LATE.
FRIDAY LOOKS QUIET WITH LOW TO MID LEVEL RIDGING BUILDING INTO
THE REGION FROM THE WEST. SHOULD BE PARTLY TO MOSTLY SUNNY AND
KEPT THE FORECAST DRY. REINFORCED CAA BEHIND THURSDAY/S TROUGH
KEEPS 850MB TEMPS OF -23 TO -24C ACROSS THE REGION FOR FRIDAY.
RATHER INEFFECTIVE SUNSHINE WITH HIGHS IN THE LOW-MID TEENS...AND
LOCALLY 8-9F IN THE NRN ADIRONDACK REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 330 AM EST WEDNESDAY...LITTLE CHANGE FROM PREVIOUS COUPLE
OF FCSTS WITH MID/UPPER LVL TROF PREVAILING ACRS THE NE CONUS AND
SEVERAL OPPORTUNITIES FOR ACCUMULATING SNOWFALL FROM SAT THRU
NEXT TUES. WEAK WARM FRNT FEATURE AND SFC LOW PRES TRACKING TO
OUR NORTH WL PRODUCE LIGHT SNOW SHOWERS ACRS OUR CWA ON SATURDAY.
TEMPS SHOULD WARM INTO THE TEENS AND 20S ON SATURDAY. A DUSTING
TO 2 INCHES LOOKS LIKELY...WITH HIGHEST VALUES ACRS THE MTNS.
MEANWHILE...LATEST 00Z GUIDANCE IS TRENDING FURTHER SOUTH WITH
SYSTEM ON MONDAY/TUESDAY...AND STRONGER WITH SFC HIGH PRES ACRS
SOUTHERN CANADA. THIS WL PROVIDE CWA WITH COLD AND DRY NORTHERLY
WINDS SUNDAY INTO MONDAY ALONG WITH SUPPRESSING BETTER
MOISTURE/LIFT ACRS THE MID ATLANTIC STATES/SNE. HOWEVER...STILL
NOTICING A SHARP NORTH TO SOUTH LLVL THERMAL GRADIENT ACRS OUR
CWA...ALONG WITH SOME ENHANCED 850 TO 500MB RH MOVING FROM SW TO
NE ACRS OUR REGION. THIS MOISTURE COMBINED WITH SEVERAL EMBEDDED
5H VORT IN THE FAST CONFLUENT WESTERLY FLW ALOFT SHOULD BE ENOUGH
TO PRODUCE A LIGHT ACCUMULATING SNOWFALL ACRS THE REGION ON
MONDAY INTO TUESDAY. FURTHERMORE...STILL THINKING MODELS WL SHIFT
BACK NORTH WITH PROGGED SFC LOW PRES TRACK...ESPECIALLY AS
SYSTEM/ENERGY ALOFT ENTERS THE WESTERN CONUS THIS WEEKEND. WL
CONT TO MENTION HIGH CHC POPS FOR THIS TIME PERIOD AND WAIT UNTIL
BETTER AGREEMENT OCCURS IN GUIDANCE BEFORE INCREASING TO LIKELY
POPS. TEMPS WL CONT TO BE TRICKY...ESPECIALLY ASSOCIATED WITH
LLVL CAA ON SUNDAY INTO MONDAY. LATEST GFS IS SHOWING 925MB TEMPS
DROPPING BTWN -22C AND -26C WITH NORTHERLY WINDS. THIS COMBINED
WITH INCREASING HIGH CLOUDS FROM APPROACHING SOUTHERN STREAM
SYSTEM SUPPORTS HIGHS ONLY IN THE SINGLE DIGITS MTNS TO L/M TEEN
VALLEYS. HAVE UNCUT SUPERBLEND BY SEVERAL DEGREES FOR HIGHS...BUT
KEPT CLOSE WITH LOWS RANGING FROM -10F TO +10F...AND HIGHLY
VARIABLE BASED ON CLOUDS/WINDS. SLIGHTLY WARMER TEMPS ARE
ANTICIPATED FOR MONDAY NIGHT INTO TUESDAY...BEFORE ADDITIONAL
COOLING ARRIVES BY THE MID OF NEXT WEEK. OVERALL....TEMPS WL
REMAIN 10 TO 20 DEGREES BLW NORMAL THRU THE PERIOD.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 06Z THURSDAY...AVIATION CHALLENGE WL BE TIMING OF ARCTIC
BOUNDARY THIS MORNING AND ASSOCIATED SNOW SHOWERS AND POTENTIAL
SNOW SQUALL. CRNT SFC ANALYSIS SHOWS COLD FRNT ACRS THE
SLV/WESTERN DACKS...WITH A NARROW BAND OF ENHANCED SNOW SHOWER
ACTIVITY WITH VIS <1SM. LATEST HRRR/RAP DATA SHOWS THIS BAND
ENTERING THE CPV BTWN 12-15Z THIS MORNING...BUT WEAKENING WITH
SOUTHWEST DOWNSLOPE FLW AND INTERACTION OFF THE DACKS. A BRIEF 20
TO 30 MINUTE WINDOW OF MVFR CONDITIONS WITH VIS AROUND 3SM IN
SNOW SHOWERS WL OCCUR...ALONG WITH A WIND SHIFT TO THE WEST AT
PBG/BTV. THINKING IFR CONDITIONS ASSOCIATED WITH BOUNDARY WL
OCCUR AFT 14Z AT MPV/RUTLAND. IN ADDITION...THE COMBINATION OF
UPSLOPE FLW AND SOME WEAK LAKE ENHANCED MOISTURE WL CONT TO
PRODUCE ON AND OFF IFR VIS IN LIGHT SNOW THRU 14Z THIS MORNING AT
SLK. SOUNDINGS SUPPORT GUSTY WEST/NORTHWEST WINDS OF 10 TO 15
KNOTS WITH GUSTS 25 TO 30 KNOTS DEVELOPING BEHIND FROPA TODAY
BTWN 14Z-22Z TODAY. THESE WINDS WL SLOWLY DISSIPATE BY SUNSET
THIS EVENING.
OUTLOOK 12Z THURSDAY THROUGH SUNDAY... MAINLY VFR CONDITIONS BTWN
06Z AND 12Z THURSDAY...BEFORE NEXT CLIPPER SYSTEM WITH SNOW
SHOWERS AND IFR/MVFR CONDITIONS DEVELOP BTWN 15Z AND 21Z THURS. A
BRIEF SNOW SQUALL WL ONCE AGAIN BE POSSIBLE ON THURS ASSOCIATED
WITH NEXT SURGE OF ARCTIC AIR. LINGERING UPSLOPE MTN SNOW SHOWERS
WL PREVAIL AT SLK/MPV INTO EARLY FRIDAY MORNING WITH PERIODS OF
IFR/MVFR POSSIBLE...ALONG WITH GUSTY WEST/NORTHWEST WINDS. SFC
HIGH PRES WITH VFR CONDITIONS DEVELOP FRIDAY INTO
SATURDAY...BEFORE NEXT SYSTEM ARRIVES ON SAT AFTN INTO SUNDAY WITH
ADDITIONAL LIGHT SNOW SHOWERS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/NEILES
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
737 AM EST WED FEB 26 2014
.SYNOPSIS...
A PROLONGED STRETCH OF COLD WEATHER...WITH TEMPERATURES RUNNING
10 TO 20 DEGREES BELOW AVERAGE...IS EXPECTED TO PERSIST THROUGH
EARLY NEXT WEEK. REINFORCING ARCTIC FRONTS MOVING FROM WEST TO
EAST ACROSS THE NORTH COUNTRY THIS MORNING AND AGAIN DURING THE
MIDDAY THROUGH AFTERNOON HOURS THURSDAY WILL BRING SCATTERED SNOW
SHOWERS AND SNOW SQUALLS. A QUICK DUSTING TO A COUPLE INCHES OF SNOW
IS POSSIBLE WITH THESE FRONTAL PASSAGES...ALONG WITH BRIEF PERIODS
OF VERY LOW VISIBILITY. HIGH TEMPERATURES TODAY WILL RANGE FROM
THE MID TEENS TO LOWER 20S...AND DEVELOPING WESTERLY WINDS OF 15
TO 25 MPH WILL RESULT IN WIND CHILL VALUES NEAR ZERO.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 732 AM EST WEDNESDAY...SNOW SHOWER ACTIVITY HAS LOST
ORGANIZATION AND STRUCTURE 10-12Z AS IT MOVED AWAY FROM THE LAKE INDUCED
INSTABILITY NEAR LAKE ONTARIO AND AS FRONTOGENETIC CIRCULATION HAS
BEEN DISRUPTED BY THE STEEP TERRAIN OF THE ADIRONDACKS.
EXPECTATION - CONSISTENT WITH 11Z RAP - IS THAT LIGHT SNOW SHOWERS
WILL SHIFT THRU THE CHAMPLAIN VALLEY NEXT 1-3 HOURS...AND THEN
SHOW AN INCREASE IN INTENSITY ACROSS CENTRAL AND ERN VT AFTER 15Z
WITH DEVELOPMENT OF STEEP LOW-LEVEL LAPSE RATES AND SBCAPE UP TO
100 J/KG. BEST CHANCE FOR BRIEF MODERATE TO HEAVY SNOW WILL BE
ACROSS THE CT RIVER VALLEY BEFORE ACTIVITY SHIFTS EAST INTO NH.
WE/LL SEE A QUICK DUSTING TO 2" IN SPOTS...HIGHEST CENTRAL/ERN VT
DURING THE MIDDAY HRS. OTHERWISE...LOOKING AT CONTINUED COLD TEMPS
WITH HIGHS IN THE MID TO UPPER TEENS...EXCEPT LOW 20S IN FAR SERN
SECTIONS. INCREASED COLD ADVECTION THIS AFTN MAY ALLOW TEMPS TO
LEVEL OFF AFTER NOON EDT. STEEP LOW-LEVEL LAPSE RATES WILL
CONTRIBUTE TO GUSTY S-SW WINDS IN ADVANCE OF THE FRONT 15-25 MPH
WITH POST- FRONTAL GUSTS TO 30 MPH...SHIFTING INTO THE WEST
FOLLOWING FRONTAL PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 342 AM EST WEDNESDAY...SFC RIDGE BUILDS BRIEFLY ACROSS THE AREA
THIS EVENING AND OVERNIGHT...ALLOWING FOR DIMINISHING WIND AND A
PERIOD OF PARTIAL CLEARING. WITH ARCTIC AIR MASS IN PLACE (850MB
TEMPS -24C)...THE RADIATIONAL COOLING WILL RESULT IN COLD
OVERNIGHT LOWS RANGING FROM NEAR ZERO IN THE CHAMPLAIN VALLEY TO
AROUND 10 BELOW IN THE ADIRONDACKS AND NORTHEAST KINGDOM. TEMPS MAY
LEVEL OFF AFTER MIDNIGHT WITH SOME INCREASE IN CLOUDS IN ADVANCE OF
NEXT SYSTEM.
NEXT SHORTWAVE TROUGH ROTATING AROUND THE SRN PERIPHERY OF PARENT
UPPER LOW ANCHORED ACROSS JAMES BAY WILL TRANSLATE ACROSS THE ERN
GREAT LAKES AROUND 12Z THURSDAY...AND ACROSS THE NORTH COUNTRY
15-21Z TIME FRAME THURSDAY. THIS NEXT SHORTWAVE IS APPEARS VIGOROUS
IN WV IMAGERY AND IN NWP PROJECTIONS...SO QG ASCENT WILL BE
MODERATELY STRONG AS UPR TROUGH APPROACHES DURING THE DAY THURSDAY.
IT APPEARS SBCAPE VALUES WILL BE BETTER ACROSS MOST SECTIONS OF THE
NORTH COUNTRY WITH THIS SYSTEM TOMORROW (AS OPPOSED TO THE WEAKER
ONE TODAY)...WITH 06Z NAM INDICATING 100-150 J/KG ACROSS MUCH OF THE
NORTH COUNTRY. ALSO INTERESTING ARE PROGGED PBL HEIGHTS TO 600MB
WITH STEEP LAPSE RATES FROM THE SFC-12 KFT...A DEFAULT TROPOPAUSE IN
THE ARCTIC AIR REGIME. SO...GOOD CONVECTIVE SNOW POTENTIAL.
FRONTOGENETIC FORCING IS NOT AS WELL ORGANIZED AS WEDNESDAY...SO
WOULD ANTICIPATE SMALLER LINE SEGMENTS AND CONVECTIVE CELLS PRODUCING
BRIEF BURSTS OF HEAVIER SNOW SHOWERS AND POSSIBLE SQUALLS WITH
GUSTS 30-35 MPH. A QUICK 1-3" IS POSSIBLE IN SPOTS...AND WILL
AGAIN CAUSE SOME BRIEF TRANSPORTATION HAZARD DUE TO LOW VSBY AND
SNOW COVERED ROADS. MADE MENTION OF THIS AS WELL IN THE MORNING
HWO. HIGHS THURSDAY IN THE UPR TEENS TO LOW 20S. SYSTEM MOVES EAST
OF THE AREA THURSDAY NIGHT WITH JUST A FEW LINGERING MTN FLURRIES.
LOWS AGAIN ZERO TO -10F...BUT LOCALLY COLDER IN THE NRN
ADIRONDACKS IF PARTIAL CLEARING CAN OCCUR LATE.
FRIDAY LOOKS QUIET WITH LOW TO MID LEVEL RIDGING BUILDING INTO THE
REGION FROM THE WEST. SHOULD BE PARTLY TO MOSTLY SUNNY AND KEPT THE
FORECAST DRY. REINFORCED CAA BEHIND THURSDAY/S TROUGH KEEPS 850MB
TEMPS OF -23 TO -24C ACROSS THE REGION FOR FRIDAY. RATHER
INEFFECTIVE SUNSHINE WITH HIGHS IN THE LOW-MID TEENS...AND LOCALLY
8-9F IN THE NRN ADIRONDACK REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 330 AM EST WEDNESDAY...LITTLE CHANGE FROM PREVIOUS COUPLE OF
FCSTS WITH MID/UPPER LVL TROF PREVAILING ACRS THE NE CONUS AND
SEVERAL OPPORTUNITIES FOR ACCUMULATING SNOWFALL FROM SAT THRU NEXT
TUES. WEAK WARM FRNT FEATURE AND SFC LOW PRES TRACKING TO OUR
NORTH WL PRODUCE LIGHT SNOW SHOWERS ACRS OUR CWA ON SATURDAY.
TEMPS SHOULD WARM INTO THE TEENS AND 20S ON SATURDAY. A DUSTING TO
2 INCHES LOOKS LIKELY...WITH HIGHEST VALUES ACRS THE MTNS.
MEANWHILE...LATEST 00Z GUIDANCE IS TRENDING FURTHER SOUTH WITH
SYSTEM ON MONDAY/TUESDAY...AND STRONGER WITH SFC HIGH PRES ACRS
SOUTHERN CANADA. THIS WL PROVIDE CWA WITH COLD AND DRY NORTHERLY
WINDS SUNDAY INTO MONDAY ALONG WITH SUPPRESSING BETTER
MOISTURE/LIFT ACRS THE MID ATLANTIC STATES/SNE. HOWEVER...STILL
NOTICING A SHARP NORTH TO SOUTH LLVL THERMAL GRADIENT ACRS OUR
CWA...ALONG WITH SOME ENHANCED 850 TO 500MB RH MOVING FROM SW TO
NE ACRS OUR REGION. THIS MOISTURE COMBINED WITH SEVERAL EMBEDDED
5H VORT IN THE FAST CONFLUENT WESTERLY FLW ALOFT SHOULD BE ENOUGH
TO PRODUCE A LIGHT ACCUMULATING SNOWFALL ACRS THE REGION ON MONDAY
INTO TUESDAY. FURTHERMORE...STILL THINKING MODELS WL SHIFT BACK
NORTH WITH PROGGED SFC LOW PRES TRACK...ESPECIALLY AS
SYSTEM/ENERGY ALOFT ENTERS THE WESTERN CONUS THIS WEEKEND. WL CONT
TO MENTION HIGH CHC POPS FOR THIS TIME PERIOD AND WAIT UNTIL
BETTER AGREEMENT OCCURS IN GUIDANCE BEFORE INCREASING TO LIKELY
POPS. TEMPS WL CONT TO BE TRICKY...ESPECIALLY ASSOCIATED WITH LLVL
CAA ON SUNDAY INTO MONDAY. LATEST GFS IS SHOWING 925MB TEMPS
DROPPING BTWN -22C AND -26C WITH NORTHERLY WINDS. THIS COMBINED
WITH INCREASING HIGH CLOUDS FROM APPROACHING SOUTHERN STREAM
SYSTEM SUPPORTS HIGHS ONLY IN THE SINGLE DIGITS MTNS TO L/M TEEN
VALLEYS. HAVE UNCUT SUPERBLEND BY SEVERAL DEGREES FOR HIGHS...BUT
KEPT CLOSE WITH LOWS RANGING FROM -10F TO +10F...AND HIGHLY
VARIABLE BASED ON CLOUDS/WINDS. SLIGHTLY WARMER TEMPS ARE
ANTICIPATED FOR MONDAY NIGHT INTO TUESDAY...BEFORE ADDITIONAL
COOLING ARRIVES BY THE MID OF NEXT WEEK. OVERALL....TEMPS WL
REMAIN 10 TO 20 DEGREES BLW NORMAL THRU THE PERIOD.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 06Z THURSDAY...AVIATION CHALLENGE WL BE TIMING OF ARCTIC
BOUNDARY THIS MORNING AND ASSOCIATED SNOW SHOWERS AND POTENTIAL
SNOW SQUALL. CRNT SFC ANALYSIS SHOWS COLD FRNT ACRS THE
SLV/WESTERN DACKS...WITH A NARROW BAND OF ENHANCED SNOW SHOWER
ACTIVITY WITH VIS <1SM. LATEST HRRR/RAP DATA SHOWS THIS BAND
ENTERING THE CPV BTWN 12-15Z THIS MORNING...BUT WEAKENING WITH
SOUTHWEST DOWNSLOPE FLW AND INTERACTION OFF THE DACKS. A BRIEF 20
TO 30 MINUTE WINDOW OF MVFR CONDITIONS WITH VIS AROUND 3SM IN SNOW
SHOWERS WL OCCUR...ALONG WITH A WIND SHIFT TO THE
WEST AT PBG/BTV. THINKING IFR CONDITIONS ASSOCIATED WITH BOUNDARY WL
OCCUR AFT 14Z AT MPV/RUTLAND. IN ADDITION...THE COMBINATION OF
UPSLOPE FLW AND SOME WEAK LAKE ENHANCED MOISTURE WL CONT TO
PRODUCE ON AND OFF IFR VIS IN LIGHT SNOW THRU 14Z THIS MORNING AT
SLK. SOUNDINGS SUPPORT GUSTY WEST/NORTHWEST WINDS OF 10 TO 15
KNOTS WITH GUSTS 25 TO 30 KNOTS DEVELOPING BEHIND FROPA TODAY BTWN
14Z-22Z TODAY. THESE WINDS WL SLOWLY DISSIPATE BY SUNSET THIS
EVENING.
OUTLOOK 12Z THURSDAY THROUGH SUNDAY... MAINLY VFR CONDITIONS BTWN
06Z AND 12Z THURSDAY...BEFORE NEXT CLIPPER SYSTEM WITH SNOW
SHOWERS AND IFR/MVFR CONDITIONS DEVELOP BTWN 15Z AND 21Z THURS. A
BRIEF SNOW SQUALL WL ONCE AGAIN BE POSSIBLE ON THURS ASSOCIATED
WITH NEXT SURGE OF ARCTIC AIR. LINGERING UPSLOPE MTN SNOW SHOWERS
WL PREVAIL AT SLK/MPV INTO EARLY FRIDAY MORNING WITH PERIODS OF
IFR/MVFR POSSIBLE...ALONG WITH GUSTY WEST/NORTHWEST WINDS. SFC
HIGH PRES WITH VFR CONDITIONS DEVELOP FRIDAY INTO
SATURDAY...BEFORE NEXT SYSTEM ARRIVES ON SAT AFTN INTO SUNDAY WITH
ADDITIONAL LIGHT SNOW SHOWERS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
632 AM EST WED FEB 26 2014
.SYNOPSIS...
A PROLONGED STRETCH OF COLD WEATHER...WITH TEMPERATURES RUNNING
10 TO 20 DEGREES BELOW AVERAGE...IS EXPECTED TO PERSIST THROUGH
EARLY NEXT WEEK. REINFORCING ARCTIC FRONTS MOVING FROM WEST TO
EAST ACROSS THE NORTH COUNTRY THIS MORNING AND AGAIN DURING THE
MIDDAY THROUGH AFTERNOON HOURS THURSDAY WILL BRING SCATTERED SNOW
SHOWERS AND SNOW SQUALLS. A QUICK DUSTING TO A COUPLE INCHES OF SNOW
IS POSSIBLE WITH THESE FRONTAL PASSAGES...ALONG WITH BRIEF PERIODS
OF VERY LOW VISIBILITY. HIGH TEMPERATURES TODAY WILL RANGE FROM
THE MID TEENS TO LOWER 20S...AND DEVELOPING WESTERLY WINDS OF 15
TO 25 MPH WILL RESULT IN WIND CHILL VALUES NEAR ZERO.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 342 AM EST WEDNESDAY...VARIABLE CLOUD COVER...WIND AND
WEATHER CONDITIONS TODAY WITH REINFORCING ARCTIC FRONTAL PASSAGE
FROM WEST-TO-EAST EXPECTED LATER THIS MORNING. EXCELLENT
CONVERGENCE NOTED ALONG APPROACHING SECONDARY/ARCTIC FRONT ACROSS
ERN LAKE ONTARIO AND WRN NY EARLY THIS AM. EARLY AM RUC MODEL
ANALYSIS INDICATES THE FRONT IS ASSOCIATED WITH STRONG SFC-925MB
FRONTOGENESIS WITH ACCOMPANYING ISALLOBARIC RISE/FALL
COUPLET...RESULTING IN ROBUST LINEAR FORCING. LAKE INDUCED
INSTABILITY UP TO 100 J/KG AND STRONG LOW-LEVEL FORCING FOR ASCENT
IS RESULTING IN NARROW CONVECTIVE BAND ALONG THE FRONT PRODUCING
SNOW SQUALL ACTIVITY WITH BRIEF PERIOD OF MODERATE TO HEAVY SNOW
(20-30 MINUTES). BTV SNOW SQUALL PARAMETER MAINTAINS SNOW SQUALL
POTENTIAL AS FRONT SHIFTS EWD CROSSING OUR REGION THIS
MORNING...BEFORE EXITING EAST OF THE CT RIVER VLY BY 18Z.
FAVORABLE FRONTOGENETIC FORCING AND LOW-LEVEL MOISTURE AND
INSTABILITY WILL BRING A BAND OF SNOW SHOWERS AND SQUALLS ACROSS
NRN NY THRU ABOUT 12-13Z. MAY SEE CONVECTIVE ACTIVITY WEAKEN
SLIGHTLY THRU THE CHAMPLAIN VALLEY WITH ABSENCE OF INSTABILITY
LOCALLY AND FLOW DISRUPTION ACROSS THE ADIRONDACK REGION.
INSTABILITY IS ACTUALLY BEST ACROSS NH/ME WITH INSOLATIONAL
HEATING IN ADVANCE OF THE BNDRY...SO AGAIN...ANTICIPATE
ORGANIZATION MAY WANE A BIT THRU THE CHAMPLAIN VLY...BUT INCREASE
AGAIN ACROSS ERN VT MIDDAY HRS BEFORE EXITING RAPIDLY EWD WITH
FROPA BY 17-18Z. SBCAPE VALUES REACH 100-150 J/KG IN NAM MODEL
SOUNDINGS ALONG THE CT RIVER BETWEEN 15-18Z TODAY JUST AHEAD OF
THE FRONTAL BNDRY. WE/LL SEE A QUICK DUSTING TO 2" IN SPOTS WITH
THESE SNOW SHOWERS AND SQUALLS...LIKELY HIGHEST IN NRN NY AND THEN
CENTRAL AND ERN VT. MAY RESULT IN SLOW TRAVEL FOR AN HOUR OR SO
DURING SQUALL PASSAGE. WE/LL CONTINUE TO HIGHLIGHT THIS POTL IN
THE HAZARDOUS WEATHER OUTLOOK AND THROUGH SOCIAL MEDIA.
OTHERWISE...LOOKING AT CONTINUED COLD TEMPS WITH HIGHS IN THE MID
TO UPPER 20S...EXCEPT LOW 20S IN FAR SERN SECTIONS. STEEP LOW-
LEVEL LAPSE RATES WILL CONTRIBUTE TO GUSTY S-SW WINDS IN ADVANCE
OF THE FRONT 15-25 MPH WITH POST- FRONTAL GUSTS TO 30
MPH...SHIFTING INTO THE WEST FOLLOWING FRONTAL PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 342 AM EST WEDNESDAY...SFC RIDGE BUILDS BRIEFLY ACROSS THE AREA
THIS EVENING AND OVERNIGHT...ALLOWING FOR DIMINISHING WIND AND A
PERIOD OF PARTIAL CLEARING. WITH ARCTIC AIR MASS IN PLACE (850MB
TEMPS -24C)...THE RADIATIONAL COOLING WILL RESULT IN COLD
OVERNIGHT LOWS RANGING FROM NEAR ZERO IN THE CHAMPLAIN VALLEY TO
AROUND 10 BELOW IN THE ADIRONDACKS AND NORTHEAST KINGDOM. TEMPS MAY
LEVEL OFF AFTER MIDNIGHT WITH SOME INCREASE IN CLOUDS IN ADVANCE OF
NEXT SYSTEM.
NEXT SHORTWAVE TROUGH ROTATING AROUND THE SRN PERIPHERY OF PARENT
UPPER LOW ANCHORED ACROSS JAMES BAY WILL TRANSLATE ACROSS THE ERN
GREAT LAKES AROUND 12Z THURSDAY...AND ACROSS THE NORTH COUNTRY
15-21Z TIME FRAME THURSDAY. THIS NEXT SHORTWAVE IS APPEARS VIGOROUS
IN WV IMAGERY AND IN NWP PROJECTIONS...SO QG ASCENT WILL BE
MODERATELY STRONG AS UPR TROUGH APPROACHES DURING THE DAY THURSDAY.
IT APPEARS SBCAPE VALUES WILL BE BETTER ACROSS MOST SECTIONS OF THE
NORTH COUNTRY WITH THIS SYSTEM TOMORROW (AS OPPOSED TO THE WEAKER
ONE TODAY)...WITH 06Z NAM INDICATING 100-150 J/KG ACROSS MUCH OF THE
NORTH COUNTRY. ALSO INTERESTING ARE PROGGED PBL HEIGHTS TO 600MB
WITH STEEP LAPSE RATES FROM THE SFC-12 KFT...A DEFAULT TROPOPAUSE IN
THE ARCTIC AIR REGIME. SO...GOOD CONVECTIVE SNOW POTENTIAL.
FRONTOGENETIC FORCING IS NOT AS WELL ORGANIZED AS WEDNESDAY...SO
WOULD ANTICIPATE SMALLER LINE SEGMENTS AND CONVECTIVE CELLS PRODUCING
BRIEF BURSTS OF HEAVIER SNOW SHOWERS AND POSSIBLE SQUALLS WITH
GUSTS 30-35 MPH. A QUICK 1-3" IS POSSIBLE IN SPOTS...AND WILL
AGAIN CAUSE SOME BRIEF TRANSPORTATION HAZARD DUE TO LOW VSBY AND
SNOW COVERED ROADS. MADE MENTION OF THIS AS WELL IN THE MORNING
HWO. HIGHS THURSDAY IN THE UPR TEENS TO LOW 20S. SYSTEM MOVES EAST
OF THE AREA THURSDAY NIGHT WITH JUST A FEW LINGERING MTN FLURRIES.
LOWS AGAIN ZERO TO -10F...BUT LOCALLY COLDER IN THE NRN
ADIRONDACKS IF PARTIAL CLEARING CAN OCCUR LATE.
FRIDAY LOOKS QUIET WITH LOW TO MID LEVEL RIDGING BUILDING INTO THE
REGION FROM THE WEST. SHOULD BE PARTLY TO MOSTLY SUNNY AND KEPT THE
FORECAST DRY. REINFORCED CAA BEHIND THURSDAY/S TROUGH KEEPS 850MB
TEMPS OF -23 TO -24C ACROSS THE REGION FOR FRIDAY. RATHER
INEFFECTIVE SUNSHINE WITH HIGHS IN THE LOW-MID TEENS...AND LOCALLY
8-9F IN THE NRN ADIRONDACK REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 330 AM EST WEDNESDAY...LITTLE CHANGE FROM PREVIOUS COUPLE OF
FCSTS WITH MID/UPPER LVL TROF PREVAILING ACRS THE NE CONUS AND
SEVERAL OPPORTUNITIES FOR ACCUMULATING SNOWFALL FROM SAT THRU NEXT
TUES. WEAK WARM FRNT FEATURE AND SFC LOW PRES TRACKING TO OUR
NORTH WL PRODUCE LIGHT SNOW SHOWERS ACRS OUR CWA ON SATURDAY.
TEMPS SHOULD WARM INTO THE TEENS AND 20S ON SATURDAY. A DUSTING TO
2 INCHES LOOKS LIKELY...WITH HIGHEST VALUES ACRS THE MTNS.
MEANWHILE...LATEST 00Z GUIDANCE IS TRENDING FURTHER SOUTH WITH
SYSTEM ON MONDAY/TUESDAY...AND STRONGER WITH SFC HIGH PRES ACRS
SOUTHERN CANADA. THIS WL PROVIDE CWA WITH COLD AND DRY NORTHERLY
WINDS SUNDAY INTO MONDAY ALONG WITH SUPPRESSING BETTER
MOISTURE/LIFT ACRS THE MID ATLANTIC STATES/SNE. HOWEVER...STILL
NOTICING A SHARP NORTH TO SOUTH LLVL THERMAL GRADIENT ACRS OUR
CWA...ALONG WITH SOME ENHANCED 850 TO 500MB RH MOVING FROM SW TO
NE ACRS OUR REGION. THIS MOISTURE COMBINED WITH SEVERAL EMBEDDED
5H VORT IN THE FAST CONFLUENT WESTERLY FLW ALOFT SHOULD BE ENOUGH
TO PRODUCE A LIGHT ACCUMULATING SNOWFALL ACRS THE REGION ON MONDAY
INTO TUESDAY. FURTHERMORE...STILL THINKING MODELS WL SHIFT BACK
NORTH WITH PROGGED SFC LOW PRES TRACK...ESPECIALLY AS
SYSTEM/ENERGY ALOFT ENTERS THE WESTERN CONUS THIS WEEKEND. WL CONT
TO MENTION HIGH CHC POPS FOR THIS TIME PERIOD AND WAIT UNTIL
BETTER AGREEMENT OCCURS IN GUIDANCE BEFORE INCREASING TO LIKELY
POPS. TEMPS WL CONT TO BE TRICKY...ESPECIALLY ASSOCIATED WITH LLVL
CAA ON SUNDAY INTO MONDAY. LATEST GFS IS SHOWING 925MB TEMPS
DROPPING BTWN -22C AND -26C WITH NORTHERLY WINDS. THIS COMBINED
WITH INCREASING HIGH CLOUDS FROM APPROACHING SOUTHERN STREAM
SYSTEM SUPPORTS HIGHS ONLY IN THE SINGLE DIGITS MTNS TO L/M TEEN
VALLEYS. HAVE UNCUT SUPERBLEND BY SEVERAL DEGREES FOR HIGHS...BUT
KEPT CLOSE WITH LOWS RANGING FROM -10F TO +10F...AND HIGHLY
VARIABLE BASED ON CLOUDS/WINDS. SLIGHTLY WARMER TEMPS ARE
ANTICIPATED FOR MONDAY NIGHT INTO TUESDAY...BEFORE ADDITIONAL
COOLING ARRIVES BY THE MID OF NEXT WEEK. OVERALL....TEMPS WL
REMAIN 10 TO 20 DEGREES BLW NORMAL THRU THE PERIOD.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 06Z THURSDAY...AVIATION CHALLENGE WL BE TIMING OF ARCTIC
BOUNDARY THIS MORNING AND ASSOCIATED SNOW SHOWERS AND POTENTIAL
SNOW SQUALL. CRNT SFC ANALYSIS SHOWS COLD FRNT ACRS THE
SLV/WESTERN DACKS...WITH A NARROW BAND OF ENHANCED SNOW SHOWER
ACTIVITY WITH VIS <1SM. LATEST HRRR/RAP DATA SHOWS THIS BAND
ENTERING THE CPV BTWN 12-15Z THIS MORNING...BUT WEAKENING WITH
SOUTHWEST DOWNSLOPE FLW AND INTERACTION OFF THE DACKS. A BRIEF 20
TO 30 MINUTE WINDOW OF MVFR CONDITIONS WITH VIS AROUND 3SM IN SNOW
SHOWERS WL OCCUR...ALONG WITH A WIND SHIFT TO THE
WEST AT PBG/BTV. THINKING IFR CONDITIONS ASSOCIATED WITH BOUNDARY WL
OCCUR AFT 14Z AT MPV/RUTLAND. IN ADDITION...THE COMBINATION OF
UPSLOPE FLW AND SOME WEAK LAKE ENHANCED MOISTURE WL CONT TO
PRODUCE ON AND OFF IFR VIS IN LIGHT SNOW THRU 14Z THIS MORNING AT
SLK. SOUNDINGS SUPPORT GUSTY WEST/NORTHWEST WINDS OF 10 TO 15
KNOTS WITH GUSTS 25 TO 30 KNOTS DEVELOPING BEHIND FROPA TODAY BTWN
14Z-22Z TODAY. THESE WINDS WL SLOWLY DISSIPATE BY SUNSET THIS
EVENING.
OUTLOOK 12Z THURSDAY THROUGH SUNDAY... MAINLY VFR CONDITIONS BTWN
06Z AND 12Z THURSDAY...BEFORE NEXT CLIPPER SYSTEM WITH SNOW
SHOWERS AND IFR/MVFR CONDITIONS DEVELOP BTWN 15Z AND 21Z THURS. A
BRIEF SNOW SQUALL WL ONCE AGAIN BE POSSIBLE ON THURS ASSOCIATED
WITH NEXT SURGE OF ARCTIC AIR. LINGERING UPSLOPE MTN SNOW SHOWERS
WL PREVAIL AT SLK/MPV INTO EARLY FRIDAY MORNING WITH PERIODS OF
IFR/MVFR POSSIBLE...ALONG WITH GUSTY WEST/NORTHWEST WINDS. SFC
HIGH PRES WITH VFR CONDITIONS DEVELOP FRIDAY INTO
SATURDAY...BEFORE NEXT SYSTEM ARRIVES ON SAT AFTN INTO SUNDAY WITH
ADDITIONAL LIGHT SNOW SHOWERS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
637 AM CST WED FEB 26 2014
.UPDATE...
ISSUED AT 637 AM CST WED FEB 26 2014
THE ONGOING WIND CHILL ADVISORY STILL LOOKS GOOD FOR THIS UPDATE.
IN ADDITION...INCREASING ISALLOBARIC WINDS STILL LOOK TO GENERATE
WINDS MEETING WIND ADVISORY CRITERIA EAST THIS AFTERNOON. AS A
RESULT...WILL LEAVE THE CURRENT HEADLINES AS IS FOR THIS UPDATE.
OTHERWISE...THE CURRENT FORECAST IS ON TRACK. NO MAJOR UPDATES WERE
REQUIRED. ONLY ADJUSTED THE HOURLY SENSIBLE WEATHER GRIDS BASED ON
CURRENT OBS/TRENDS. THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CST WED FEB 26 2014
THERE ARE SEVERAL CONCERNS IN THE SHORT TERM PERIOD INCLUDING THE
WIND CHILL ADVISORY THIS MORNING...FOLLOWED BY WINDS FROM MID
MORNING INTO THE AFTERNOON.
EARLY MORNING SURFACE ANALYSIS PLACED HIGH PRESSURE FROM SOUTHERN
NORTH DAKOTA SOUTHWARD INTO THE CENTRAL PLAINS. A COLD FRONT IS
EXPECTED TO MOVE ACROSS THE FORECAST AREA TODAY...BRINGING AN
INCREASE IN NORTHWEST WINDS AS THE FRONT PASSES.
FIRST REGARDING THE WIND CHILL ADVISORY...THE HEADLINE LOOKS TO BE
WELL PLACED. WIND CHILLS SOUTH AND WEST OF THE MISSOURI RIVER HAVE
GENERALLY REMAINED WARMER THAN ADVISORY LEVELS DUE IN PART TO WEAKER
WINDS IN PROXIMITY TO THE SURFACE RIDGE AXIS. WILL LEAVE THE WIND
CHILL ADVISORY IN ITS CURRENT CONFIGURATION SINCE AREAS NORTH AND
EAST OF THE MISSOURI RIVER CONTINUE TO SEE WIND CHILLS OF 25 TO 35
BELOW.
WINDS SPEEDS WILL BE THE NEXT CONCERN AS LOW LEVEL COLD AIR
ADVECTION TAKES HOLD BEHIND THE COLD FRONT. THE STRONGEST
PRESSURE RISE / FALL COUPLET IS ACROSS MINNESOTA INTO EASTERN NORTH
DAKOTA...BUT CLIPS THE EASTERN PART OF THE FORECAST AREA. LOW
LEVEL LAPSE RATES ALSO BECOME STEEPEST FROM THE JAMES RIVER VALLEY
AND EAST. MOMENTUM TRANSFER FROM RAP BUFR SOUNDINGS SUGGEST AREAS
OUTSIDE OF THE ADVISORY COULD BRIEFLY APPROACH ADVISORY
LEVELS...BUT THAT APPEARS SHORT LIVED AND THINK THE HEART OF THE
STRONGEST WINDS SHOULD BE IN THE EASTERN PART OF THE FORECAST
AREA. WILL ONLY MAKE A SMALL ADJUSTMENT TO THE WIND ADVISORY BY
ADDING DICKEY COUNTY WHICH LINES UP WELL WITH SURROUNDING OFFICES.
WILL CONTINUE TO MENTION THE POSSIBILITY OF BLOWING SNOW AND
REDUCED VISIBILITIES...BUT DO NOT THINK VISIBILITIES SHOULD FALL TO
1/2SM OR BELOW...SO DID NOT GO WITH A WINTER WEATHER ADVISORY.
IT WILL BE COLD AGAIN TONIGHT WITH WIND CHILLS AGAIN POTENTIALLY
FALLING TO ADVISORY LEVELS NORTH AND EAST OF THE MISSOURI RIVER.
WITH MULTIPLE HEADLINES ALREADY IN PLACE...DID NOT PUT OUT A
HEADLINE FOR THE WIND CHILLS TONIGHT...BUT EXPECT LATER SHIFTS
WILL HAVE TO CONSIDER THAT POSSIBILITY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 314 AM CST WED FEB 26 2014
WELL BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE EXTENDED
WITH SNOW CHANCES STILL ON TAP FOR THIS WEEKEND.
SOUTHERLY RETURN FLOW WILL INCREASE THURSDAY AHEAD OF AN
APPROACHING COLD FRONT. NOT MUCH IN THE WAY OF WARM AIR ADVECTION
IS FORECAST WITH HIGHS FROM AROUND ZERO EAST TO THE LOW TEENS
WEST. THE COLD FRONT WILL PUSH THROUGH THE STATE FRIDAY MORNING
WITH BREEZY CONDITIONS EXPECTED TO DEVELOP IN ITS WAKE. THE MEDIUM
RANGE MODELS MAINTAIN A DRY FROPA.
WITH THE SURGE OF ARCTIC AIR...A BAROCLINIC ZONE IS STILL PROGGED
TO SET UP OVER SOUTHWESTERN NORTH DAKOTA FRIDAY AFTERNOON/NIGHT.
THIS SHOULD PROVIDE ENOUGH ELEVATED CONVERGENCE TO GENERATE A
CHANCE OF SNOW SOUTHWEST LATE FRIDAY INTO SATURDAY.
THE MEDIUM RANGE MODELS BEGIN TO DIVERGE WITH RESPECT TO THE
SYNOPTIC PATTERN OVER THE NORTHERN PLAINS SUNDAY THROUGH THE END
OF THE PERIOD. THE LATEST GFS IS DEEPER AND MORE PROGRESSIVE WITH
AN UPPER LOW OVER THE CANADIAN ROCKIES SATURDAY MOVING THROUGH THE
NORTHERN PLAINS SUNDAY. HOWEVER...THE LATEST ECMWF PINCHES OFF THE
UPPER LOW OVER THE CANADIAN ROCKIES WHERE IT BECOMES STATIONARY
THROUGH THE END OF THE PERIOD. GIVEN THE MODEL TO MODEL AND RUN TO
RUN INCONSISTENCIES...FORECAST A BLEND OF SOLUTIONS WITH SNOW
CHANCES SUNDAY...AND DRY CONDITIONS OVER WESTERN AND CENTRAL NORTH
DAKOTA MONDAY AND TUESDAY. REGARDLESS OF WHICH SOLUTION
VERIFIES...WELL BELOW TEMPERATURES ARE STILL FORECAST THROUGH THE
END OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 637 AM CST WED FEB 26 2014
MAINLY CLEAR SKIES ARE EXPECTED AT THE TERMINAL LOCATIONS. THE MAIN
CONCERN WILL BE INCREASING WINDS AS A COLD FRONT MOVES ACROSS THE
REGION. WINDS WILL BECOME GUSTY FROM THE NORTHWEST...WITH THE
STRONGEST WINDS EXPECTED FROM KMOT TO KJMS. CONTINUED TO CARRY THE
6SM IN BLSN AT KMOT AND KJMS ONCE THE WINDS INCREASE. WINDS WILL
DIMINISH THIS WEDNESDAY EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY UNTIL 10 AM CST THIS MORNING FOR NDZ001>005-
009>013-021>023-025-035>037-046>048-050-051.
WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR NDZ004-005-012-013-022-023-025-037-048-051.
&&
$$
UPDATE...TM
SHORT TERM...CK
LONG TERM...TM
AVIATION...CK
AREA FORECAST DISCUSSION
NWS PORTLAND OR
218 AM PST WED FEB 26 2014
.SYNOPSIS...HIGH PRESSURE ALOFT WILL SHIFT EAST TODAY AS AN ELONGATED
FRONTAL SYSTEM MOVES CLOSER TO THE COAST. OFFSHORE LOW-LEVEL FLOW
CONTINUES TODAY...BUT WEAKENS IN THE AFTERNOON. A SERIES OF WEAK
IMPULSES WITHIN THE SOUTH FLOW ALOFT WILL TRAVERSE THE AREA TODAY FOR
A THREAT OF LIGHT RAIN...MAINLY OVER THE COAST AND COAST RANGE. THE
UPPER LOW ENTERS SW OREGON OVERNIGHT INCREASING THE RAIN THREAT OVER
THE AREA. A LOW PRESSURE AREA REMAINS PARKED OFF THE NRN CALIFORNIA
OR FAR SOUTH OREGON COAST THURSDAY. WEAK HIGH PRESSURE RETURNS
FRIDAY. IT LOOKS LIKE MUCH COOLER AIR WILL WORK ITS WAY INTO THE
WASHINGTON ZONES AND INTO THE COLUMBIA GORGE OVER THE WEEKEND. MILDER
WEST FLOW ALOFT RETURNS EARLY NEXT WEEK.
&&
.SHORT TERM...WEDNESDAY THROUGH FRIDAY...THE FORECAST AREA REMAINS
UNDER A LARGE-SCALE BLOCKING PATTERN EARLY THIS MORNING. WATER VAPOR
IMAGERY WITH 500 MB HEIGHT LINES SHOWS AN UPPER RIDGE AXIS FROM NEAR
VANCOUVER ISLAND THROUGH THE WASHINGTON CASCADES AND TO FAR SERN
OREGON. MEANWHILE...A SPLITTING UPPER TROUGH RESIDES OUT NEAR 140W
WITH THE MAIN ENERGY ALONG 40N. FINALLY...THE LARGE HUDSON BAY LOW IS
KEEPING EVERYTHING IN PLACE.
THE GFS AND 03Z HRRR BOTH INDICATE A BAND OF PRECIP MOVING INTO THE
SWRN PART OF THE AREA BETWEEN 15Z AND 18Z THIS MORNING. THE HRRR
SHOWS THIS LIGHT PRECIP ACTIVITY REACHING THE CENTRAL OREGON COAST
AND COAST RANGE AROUND 15Z...THEN DRIFTING E TO NE THROUGH THE
MORNING. TIME-HEIGHT...CROSS-SECTION AND MODEL SOUNDING ANALYSIS ALL
INDICATE MID-LEVEL MOISTURE...700-800 MB...REACHING THE CENTRAL COAST
BY SUNRISE. THE COLUMN CONTINUES TO SATURATE FROM THE TOP DOWN
THROUGH THE MORNING. THIS PRECIP ACTIVITY SHOULD NOT AMOUNT TO
MUCH...BUT WILL BE AIDED BY UPPER LEVEL DIVERGENCE. THIS PRECIP WILL
ENCOUNTER THE MODERATE OFFSHORE LOW-LEVEL FLOW AS IT DRIFTS N TOWARD
THE COLUMBIA RIVER. BEST CHANCES FOR PRECIP THIS AFTERNOON WILL BE
OVER THE FAR SOUTH AND ALSO ALONG THE CASCADES.
THE KTTD-KDLS GRADIENT WAS -9.3 MB AT 09Z. CORBETT GUSTING TO NEAR 55
MPH...WITH SEVERAL LOCATIONS IN THE EAST PORTLAND AND VANCOUVER METRO
AREA GUSING TO AT LEAST 35 MPH. PEAK OFFSHORE GRADIENT VIA THE LATEST
NAM LOOKS TO BE THIS MORNING. NAM DROPS THE KTTD-KDLS GRADIENT TO 4-5
MB BY 21Z. MAY NOT DROP QUITE THAT FAST...BUT THE AM CONFIDENT WIND
WILL EASE THIS AFTERNOON.
PATTERN CHANGES TONIGHT AND THU AS THE UPPER RIDGE AXIS FINALLY
SHIFTS TO THE EAST. GFS AND ECMWF SHOW A 500 MB LOW PRES AREA FORMING
NEAR 40N 127W BY 06Z THU. SOUTH DIFFLUENT FLOW ALOFT BECOMES MORE
PRONOUNCED THIS EVENING AS THE LOW MOVES CLOSER TO THE N CA AND FAR
SRN OREGON COAST. EXPECT PRECIP TO SPREAD NWD THIS EVENING AND
TONIGHT. MODELS CLEARLY SHOW A DEFORMATION BAND SETTING UP ACROSS THE
CENTRAL PORTION OF THE AREA AROUND MIDNIGHT THEN DRIFTING NWD
OVERNIGHT AND FINALLY MOVING INTO SW WA THU MORNING. MODELS TREAT THE
UPPER LOW A BIT DIFFERENT...BUT BOTH THE GFS AND ECMWF SHOW THE LOW
FILLING AND BECOMING AN OPEN TROUGH 18Z THU AS IT DRIFT N TO NE
THROUGH SWRN OREGON. EXPECT PRECIP TO SLOWLY WANE FROM S TO N THU
AFTERNOON AND EVENING. LARGE-SCALE PATTERN REVERTS TO SOMETHING CLOSE
TO WHAT IT IS NOW THU NIGHT. INTERESTING SYNOPTIC SITUATION SETS UP
LATE THU NIGHT AND FRI. MODELS SHOW A CLOSED LOW OUT NEAR 35N
130W...A PINCHED-OFF RIDGE IN THE GULF OF ALASKA AND A LARGE BUT COLD
CANADIAN TROUGH TRYING TO RETROGRADE TO THE WEST. GFS AND ECMWF
SUGGEST SOME OF THIS COLDER AIR MAY START TO FILTER IN CENTRAL
WASHINGTON FRI AND THEN SLIDE SOUTH ALONG THE CASCADES AND INTO THE
CENTRAL COLUMBIA GORGE BY 00Z SAT. WEISHAAR
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...MUCH OF THE EXCITEMENT
FOR THE EXTENDED OCCURS THIS UPCOMING WEEKEND AND MONDAY. THE COLD
AIR MENTIONED ABOVE IN THE SHORT-TERM SECTION BECOMES MORE
ESTABLISHED OVER THE WEEKEND. LOOKS TO BE A SIMILAR SCENARIO TO THIS
PAST SUNDAY AND MONDAY WITH A SNOW-THREAT FOR THE UPPER HOOD RIVER
VALLEY. THIS COLDER AIR WILL CONTINUE TO SPILL INTO THE COLUMBIA
GORGE THIS WEEKEND. MODELS HAVE MAJOR DIFFERENCES HANDLING THE COLD
AIR SUNDAY. GFS FORCES THE MILDER WESTERLIES INTO THE PAC NW SUN
WHILE THE ECMWF CONTINUES TO RETROGRADE THE COLD UPPER LOW INTO SRN
B.C....WITH A DISTINCT COLD AIR BOUNDARY ACROSS WRN WA. ECMWF ALSO
SHOWS SOME OVER-RUNNING PRECIP MOVING INTO WRN WA AND OREGON SUN.
THIS WOULD BE A PRIME POTENTIAL SNOW SITUATION FOR SWRN WA AND IN THE
COLUMBIA GORGE SHOULD THE ECMWF VERIFY. THE GEM IS MORE LIKE THE
GFS...SHUNTING THE COLD AIR FURTHER TO THE EAST SUN. MONDAY COULD
ALSO BE A GOOD SNOW SITUATION FOR SWRN WA AND AREAS NEAR THE COLUMBIA
GORGE IF THE ECMWF IS RIGHT. HOWEVER...THE GFS IS NEARLY 24-HRS
SLOWER COMPARED TO THE ECMWF. ALL IN ALL...FORECASTER CONFIDENCE IS
RATHER LOW SUNDAY AND BEYOND. WEISHAAR
&&
.AVIATION...EAST WINDS ARE THE MAIN AVIATION IMPACT TODAY. THESE
WINDS ARE STRONGEST IN THE NORTHERN PORTION OF THE FORECAST
AREA...WITH THE GREATEST IMPACTS FOR KTTD AND KPDX. EAST WINDS
GUSTY AT TIMES WILL PERSIST THROUGH THE MORNING...EASING IN THE
AFTERNOON. OTHERWISE VFR CONDITIONS WITH MAINLY THIN AND HIGH
CLOUDS. THE EAST WINDS HAVE DRIED THE LOWER LEVELS SOME...AND DO
NOT EXPECT ANY FOG THIS MORNING. A FRONT WILL BRING A CHANCE OF
RAIN FROM THE SOUTH EARLY THIS AFTERNOON THEN TO THE NORTH MAINLY
OVER THE CASCADES AND COAST RANGE LATER THIS AFTERNOON. CIGS WILL
LOWER AS THE FRONT NEARS BUT EXPECT CONDITIONS TO GENERALLY REMAIN
VFR. THERE WILL BE MORE WIDESPREAD RAIN WITH MVFR CONDITIONS LATE
TONIGHT INTO THU MORNING.
KPDX AND APPROACHES...VFR WITH EAST WINDS 10 TO 20 KT THROUGH
THIS MORNING. WINDS WILL EASE THIS AFTERNOON. CLOUDS WILL INCREASE
IN THE AFTERNOON AS A FRONT BUT EXPECT CONDITIONS TO REMAIN VFR.
THERE IS A SLIGHT CHANCE OF A FEW SPRINKLES AFT 22Z.THERE WILL BE
A GREATER CHANCE FOR RAIN AND MVFR CONDITIONS LATE TONIGHT INTO
THU MORNING. HARTLEY
&&
.MARINE...OFFSHORE WINDS CONTINUE MARGINAL SMALL CRAFT CONDITIONS
NORTH OF CANNON BEACH THIS MORNING. THE SURFACE PRESSURE GRADIENT
WILL RELAX LATER THIS MORNING AS THE HIGH PRESSURE INLAND WEAKENS
AND SHIFTS TO THE NE...AND THE WINDS WILL EASE. RELATIVELY LIGHT
E-SE WINDS WILL CONTINUE THROUGH THURSDAY NIGHT.
A COMPLEX LOW OFFSHORE HAS GENERATED A W-SW SWELL THAT WILL BUILD
IN THE WATERS TODAY. ALTHOUGH THE BUOYS THE PAST 12 HOURS HAVE
SHOWN THE SEAS TO BE A COUPLE OF FEET LOWER THAN GUIDANCE...THERE
IS SOME EVIDENCE THAT THE FORECAST SWELL IS ON THE WAY. A BUOY FAR
TO THE SE OF THE WATERS..46002 HAS BEEN REPORTING 14 TO 16 FT AT
15 SECONDS AS THE ENP FORECASTED. THE DIRECTION OF THIS BUOY FROM
46029 IS AROUND 230 DEGREES. SINCE THE EXPECTED SWELL IS 240
DEGREES THIS BUOY IS A GOOD INDICATOR OF WHAT IS TO COME OF THIS
SWELL. A SIMPLE DECAY TOOL SUGGEST THIS SWELL WILL BE 11 TO 13 FT
AT 16 SECONDS AS IT MOVES THROUGH THE NORTHERN OREGON WATERS LATER
THIS MORNING AND AFTERNOON. CONFIDENCE IS HIGHER THAT AT LEAST THE
SOUTHERN WATERS...SOUTH OF CASCADE HEAD...WILL HAVE SMALL CRAFT
SEAS...AND HAVE ISSUED AN ADVISORY. BUOY 46050 THE PAST COUPLE OF
HOURS HAS BEEN SHOWING INCREASING HEIGHTS WHICH IS ANOTHER
INDICATOR THAT THE WELL IS ON THE WAY. HARTLEY
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 6 AM PST EARLY THIS
MORNING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
CASCADE HEAD OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 10 AM THIS MORNING
TO 10 PM PST THIS EVENING FOR COASTAL WATERS FROM CASCADE HEAD
OR TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM NOON
TODAY TO 4 PM PST THIS AFTERNOON.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 2 AM TO
6 AM PST THURSDAY.
&&
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1003 AM EST WED FEB 26 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION THIS MORNING AND USHER IN COOLER
CANADIAN HIGH PRESSURE. THIS HIGH WILL BECOME REINFORCED FROM THE
NORTH ON FRIDAY AND LINGER INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM EST WEDNESDAY...LATEST RADAR IMAGERY CONTINUES TO
INDICATE SHOWER ACTIVITY SOUTH OF INTERSTATE 85 ASSOCIATED WITH
EARLIER WEAK FRONTAL BOUNDARY PASSAGE. MOST RECENT HIGHRES NEAR
TERM GUIDANCE SOLUTIONS YIELD DECREASING COVERAGE OVER THE NEXT 2-3
HOURS FOR THESE ZONES. ADDITIONALLY...CONFIDENCE CONTINUES TO
DECREASE ON ANY SNOW SHOWER ACTIVITY ALONG THE HIGH TERRAIN OF NC
ASSOCIATED WITH WEAK NORTHWEST FLOW THEREFORE DECIDED TO LOWER POPS
FURTHER WITH ALL MENTIONABLE POPS REMOVED BY 16Z ALONG THE TN
BORDER. OTHERWISE...FORECAST REMAINS ON TRACK AND ASIDE FROM TWEAKS
TO TEMPERATURES AND DEWPOINTS...NO OTHER SIGNIFICANT CHANGES MADE.
LOW RH AND INCREASING WINDS CONTINUE TO PRESENT MODEST FIRE WX
CONCERNS TOMORROW...ESPECIALLY IN THE HIGH TERRAIN OF NC. PLEASE
REFER TO FIRE WX SECTION OF AFD FOR DETAILS.
PREVIOUS DISCUSSION...
AS OF 615 AM EST...SHORTWAVE ROTATES THRU THE ERN CONUS UPPER TROUGH
THIS MORNING...WITH COLD FRONT USHERING IN HIGH PRESSURE AND A MUCH
COLDER AIRMASS OVER THE COURSE OF THE DAY. WESTERLY MIDLEVEL WINDS
PRIOR TO THE FRONT WILL PROVIDE SLIGHT WARM ADVECTION AND ASSOCIATED
LIFT...BUT MODELS SEEM TO RESPOND MORE TO INTERACTION OF FRONTAL
CONVERGENCE WITH INCUMBENT MOISTURE ACRS GA/SC.
MESO MODELS INCLUDING LATEST COUPLE HRRR RUNS CONFINE QPF RESPONSE
WELL SOUTH OF I-85. GFS AND SREF HOWEVER FAVOR MORE OF THE PRECIP
DEVELOPING ACRS THE UPSTATE. THIS IS NOT WELL SUPPORTED BY RADAR
TRENDS SO FAR THIS AM. BEST POPS STILL LOOK TO BE IN 12-15Z
TIMEFRAME AS THE FRONT ENTERS THE LOWER PIEDMONT. DESPITE LACK OF
MODEL RESPONSE...GIVEN THE SETUP IT IS REASONABLE TO INCLUDE SCHC
POPS A BIT FURTHER NORTH...WITH TIGHT THERMAL GRADIENT ACRS THE FA
IN EXIT REGION OF THE SHORTWAVE THRU THE MRNG. NW FLOW STILL LOOKS
TO HAVE SUFFICIENT ORIENTATION AND MOISTURE TO PRODUCE BRIEF LIGHT
SNOW IN THE MTNS...BUT LATEST GUIDANCE SUPPORTS ONLY CHC POPS AND
MINIMAL ACCUMS. IN FACT THIS MAY BE A BIT OPTIMISTIC GIVEN LACK OF
RADAR RETURNS OVER EAST TN.
CLEARING OF THE LOW-MID CLOUDS ASSOCIATED WITH THE FRONTAL ZONE IS
EXPECTED TO RAPIDLY OCCUR THRU MIDDAY LEAVING A MOSTLY SUNNY AFTN.
GIVEN THE COLD AND NEWLY ARRIVED AIR MASS BUT ALSO ABUNDANT SUNSHINE
AND SLIGHT DOWNSLOPING...A BLEND OF MOS AND RAW TEMPS IS APPROPRIATE
WHICH CONTINUES TO SUPPORT TEMPS A COUPLE CATEGORIES BELOW NORMAL
EXCEPT IN THE HIGH TERRAIN WHERE MANY AREAS WON/T RISE OUT OF THE
30S. TONIGHT...WINDS BECOME LIGHT AND SKIES REMAIN CLEAR AND LOWS
DROP INTO THE TEENS MTNS AND 20S PIEDMONT.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
AS OF 200 AM WEDNESDAY...A DRY COLD FRONT WILL CROSS THE REGION
DURING THE DAY ON THURSDAY...LOWERING DEWPOINTS EVEN FURTHER. WITH
BREEZY TO WINDY CONDITIONS OVER THE NC MTNS AND FOOTHILLS...THE
POTENTIAL EXITS FOR CRITICAL FIRE WEATHER CONDITIONS. PLEASE SEE THE
FIRE WEATHER PART OF THE DISCUSSION FOR MORE DETAILS.
OTHERWISE...DRY COLD AIR DAMMING WILL BECOME MORE PRONOUNCED OVER
THE REGION THURSDAY NIGHT AND FRIDAY. THE THICKNESS TROUGH IN THE
LEE SHOULD RESULT IN COLD CONDITIONS THU NIGHT AND WELL BELOW
NORMAL TEMPERATURES ON FRIDAY. THURSDAY WE SHOULD SEE CLEAR...BLUE
SKIES. SKIES REMAIN CLEAR THU NIGHT...BUT HIGH CLOUDS SHOULD BE ON
THE INCREASE DURING THE DAY ON FRIDAY. A FAST MOVING SHORT WAVE WILL
CROSS THE NC ZONES FRI NIGHT. MOST OF THE FORCING WITH THE WAVE
PASSES NORTH OF THE FORECAST AREA. HOWEVER...LLVL WARM ADVECTION
OVER THE WRN PIEDMONT MAY SUPPORT SOME PATCHY LIGHT PCPN OVER THE
ERN ZONES. THERE ALSO APPEARS TO BE SUFFICIENT FORCING ACROSS THE
MTNS TO SUPPORT CHANCE POPS AS WELL. I USED THE BOURGOUIN TECHNIQUE
WHICH STARTS PCPN AS RAIN EARLY FRIDAY NIGHT WITH A TRANSITION TO
SNOW AND THEN FREEZING RAIN OVER MOST OF THE NC ZONES. UNDERSTAND
THAT QPF IS VERY LIGHT WITH THIS EVENT AND POPS ARE GENERALLY IN THE
LOW CHANCE TO SLIGHT CHANCE RANGE. THAT/S TO SAY...THE WEATHER GRID
LOOKS SCARIER THAN THE REALITY OF THE SITUATION. STILL...WE COULD
SEE A LIGHT ACCUMULATION OF SNOW OR ICE NORTH OF I40 AND OVER PARTS
OF THE NC MTNS FRIDAY NIGHT...BUT THE PCPN IS SO LIGHT I DON/T EVEN
PLAN TO MENTION IT IN THE HWO ATTM.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AS OF 230 AM EST WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z
ON SUNDAY WITH WHATS LEFT OF AN UPPER SHORTWAVE MOVING OUT OVER THE
ATLANTIC AND UPPER RIDGING BUILDING OVER THE GULF OF MEXICO AND SE
CONUS. THE LONG RANGE MODELS ARE TRYING TO CLOSE OFF AN H5 LOW OVER
EXTREME SOUTHERN BRITISH COLUMBIA EARLY SUNDAY WITH THE NEWER RUN OF
THE GFS BEING MORE PRONOUNCED. AS WE MOVE INTO MONDAY...HEIGHTS
BEGIN TO LOWER AGAIN AS A COMPLEX UPPER TROF PATTERN MOVES SE ACROSS
THE FAR NORTHERN PLAINS AND INTO THE GREAT LAKES REGION. THE MODELS
INDICATE THAT THE MAIN TROF AXIS WILL LIKELY BE NORTH OF THE
CAROLINAS BY LATE TUES/EARLY WED AND PERSIST OVER THE REGION THRU
DAY 7. OVERALL...THE LONG RANGE MODELS APPEAR TO BE COMING INTO
BETTER AGREEMENT WRT THE PROGRESSION AND TIMING OF THIS UPPER TROF
SYSTEM...WITH THE GFS BEING MORE AMPLIFIED AND BRINGING THE SYSTEM
FARTHER SOUTH COMPARED TO THE ECMWF.
AT THE SFC...THE HIGH CENTERED OVER NEW ENGLAND HELPING TO PRODUCE A
COLD AIR WEDGE PATTERN OVER THE CAROLINAS WILL BE MOVING WELL OFF
THE COAST BY EARLY SUN. THE MODELS CONTINUE TO MAINTAIN ANOTHER
BERMUDA TYPE HIGH CENTERED TO OUR EAST ON SUN AND EARLY MON. THEY
ALSO SPIN UP A LOW OVER THE SOUTHERN MISS RIVER VALLEY EARLY MON AND
MOVE IT OVER THE CWFA BY MON AFTERNOON. WHAT HAPPENS OVER THE NEXT
24 TO 36HRS VARIES CONSIDERABLY BETWEEN THE GFS AND ECMWF. THE GFS
KEEPS THE LOW AND ITS ASSOCIATED REGION OF BROAD AND DEEP MOISTURE
OVER THE FCST AREA THRU TUES AFTERNOON BEFORE MOVING IT NE AND
OFFSHORE...WHILE THE ECMWF AND CMC MOVE IT OFFSHORE BY MON EVENING
WITH DRIER HIGH PRESSURE SPREADING OVER THE REGION IN ITS WAKE ON
TUES. BOTH MODELS AGREE THAT THE REMAINDER OF THE FCST SHOULD BE DRY
HIGH PRESSURE OVER THE AREA ON WED. TEMPS WILL START OUT WELL ABOVE
NORMAL FOR EARLY MARCH WITH HIGHS ON SUN IN THE MID 60S FOR THE
LOWER ELEVATIONS AND UPPER 50S TO LOW 60S FOR THE HIGHER TERRAIN. BY
THE END OF THE PERIOD...I ANTICIPATE THAT VALUES WILL COOL BACK DOWN
BELOW CLIMATOLOGY.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...LOW VFR CLOUDINESS LINGERS THIS MRNG IN WARM UPGLIDE PRIOR
TO ARRIVAL OF COLD FRONT. PRECIP CHANCES DUE TO THE UPGLIDE ARE
LOW...WITH SHORT TERM GUID KEEPING MOST OF THE RESPONSE WELL SOUTH.
A FEW SPRINKLES OR BRIEF -SHRA ARE POSSIBLE THRU MID MRNG...BUT
WITHOUT RESTRICTIONS. MAINLY NE WINDS PRIOR TO THE FROPA...POSSIBLY
KEPT CLOSER TO 090 DUE TO LEE TROUGHING. NW WINDS AND CLEARING SKIES
BY MIDDAY POST FROPA. SKC LIKELY OVERNIGHT...BUT NAM/GFS BOTH TRY TO
DEVELOP SOME SPOTTY LOW VFR CLOUDS DUE TO LLVL CONVERGENCE IN THE
LEE OF THE MTNS. THIS IS A BIT UNUSUAL AND IS NOT BACKED UP BY MOS
SO WILL NOT REFLECT IN TAF.
ELSEWHERE...PRECIP CHANCES THIS AM ARE TOO LOW TO MENTION EXCEPT AT
KAND...WHICH WILL BE NEARER THE BEST LIFT/MSTR ASSOCIATED WITH WARM
ADVECTION OVER THE DEEP SOUTH. CIGS LIKELY TO STAY LOW VFR AT
WORST...BUT WILL MONITOR UPSTREAM OBS FOR LOWER CIGS WHICH MIGHT BE
ASSOCIATED WITH PRECIP. NW FLOW INTO THE MTNS WILL PRODUCE A FEW
-SHSN BUT THESE SHOULD BE VERY LIGHT AND MAY NOT CAUSE SGFNT
REDUCTION IN VSBY. EXCEPT AT KAVL WHICH REMAINS NW...NELY WINDS WILL
PREVAIL UNTIL THE FRONT PASSES AND SKIES GRADUALLY CLEAR. POST FROPA
WINDS WILL MAINLY BE NW BEFORE VEERING TONIGHT.
OUTLOOK...DRY/VFR THU-FRI...BUT PRECIPITATION AND ASSOCIATED
RESTRICTIONS ARE POSSIBLE EARLY SAT.
CONFIDENCE TABLE...
15-21Z 21-03Z 03-09Z 09-15Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.FIRE WEATHER...
LAND MANAGEMENT PARTNERS SHOULD EXPECT COORDINATION THIS
AFTERNOON FOR POSSIBLE FIRE WEATHER WATCH OR FIRE DANGER
STATEMENTS FOR THURSDAY.
THERE IS LITTLE CHANGE IN THINKING FROM THE PREVIOUS FORECAST
CYCLE. THE PLANNING FORECAST HAS BEEN UPDATED THROUGH TOMORROW
BASED UPON THE LATEST FORECAST DATA...PRIMARILY FOR MINOR CHANGES
IN SMOKE MANAGEMENT PARAMETERS. RH HAS ALSO BEEN LOWERED SLIGHTLY
FOR THIS AFTERNOON...BUT MIN RH OF 25 PERCENT OR LESS IS EXPECTED
TO BE LOCALIZED AND BRIEF...WHILE WINDS SHOULD GRADUALLY DIMINISH
THROUGH THE AFTERNOON.
AS THE AIR MASS BEGINS TO WARM ON THURSDAY...RH IS EXPECTED TO FALL
BELOW 20 PERCENT IN MOST AREAS DURING THE AFTERNOON. IN ADDITION...
W/NW WINDS WILL BEGIN TO INCREASE AHEAD OF ANOTHER DRY COLD FRONT
DURING THE AFTERNOON. WINDS MAY GUST AS HIGH AS 30 MPH IN THE
MTNS...AND TO AROUND 20 MPH IN THE PIEDMONT. CRITICAL WIND AND RH
MAY OVERLAP FOR SEVERAL HOURS ACROSS THE MTNS AND NC FOOTHILLS THU
AFTERNOON.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...WIMBERLEY
SHORT TERM...MCAVOY
LONG TERM...JPT
AVIATION...WIMBERLEY
FIRE WEATHER...LANE
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
627 AM EST WED FEB 26 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION THIS MORNING AND USHER IN COOLER
CANADIAN HIGH PRESSURE. THIS HIGH WILL BECOME REINFORCED FROM THE
NORTH ON FRIDAY AND LINGER INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 615 AM EST...SHORTWAVE ROTATES THRU THE ERN CONUS UPPER TROUGH
THIS MORNING...WITH COLD FRONT USHERING IN HIGH PRESSURE AND A MUCH
COLDER AIRMASS OVER THE COURSE OF THE DAY. WESTERLY MIDLEVEL WINDS
PRIOR TO THE FRONT WILL PROVIDE SLIGHT WARM ADVECTION AND ASSOCIATED
LIFT...BUT MODELS SEEM TO RESPOND MORE TO INTERACTION OF FRONTAL
CONVERGENCE WITH INCUMBENT MOISTURE ACRS GA/SC.
MESO MODELS INCLUDING LATEST COUPLE HRRR RUNS CONFINE QPF RESPONSE
WELL SOUTH OF I-85. GFS AND SREF HOWEVER FAVOR MORE OF THE PRECIP
DEVELOPING ACRS THE UPSTATE. THIS IS NOT WELL SUPPORTED BY RADAR
TRENDS SO FAR THIS AM. BEST POPS STILL LOOK TO BE IN 12-15Z
TIMEFRAME AS THE FRONT ENTERS THE LOWER PIEDMONT. DESPITE LACK OF
MODEL RESPONSE...GIVEN THE SETUP IT IS REASONABLE TO INCLUDE SCHC
POPS A BIT FURTHER NORTH...WITH TIGHT THERMAL GRADIENT ACRS THE FA
IN EXIT REGION OF THE SHORTWAVE THRU THE MRNG. NW FLOW STILL LOOKS
TO HAVE SUFFICIENT ORIENTATION AND MOISTURE TO PRODUCE BRIEF LIGHT
SNOW IN THE MTNS...BUT LATEST GUIDANCE SUPPORTS ONLY CHC POPS AND
MINIMAL ACCUMS. IN FACT THIS MAY BE A BIT OPTIMISTIC GIVEN LACK OF
RADAR RETURNS OVER EAST TN.
CLEARING OF THE LOW-MID CLOUDS ASSOCIATED WITH THE FRONTAL ZONE IS
EXPECTED TO RAPIDLY OCCUR THRU MIDDAY LEAVING A MOSTLY SUNNY AFTN.
GIVEN THE COLD AND NEWLY ARRIVED AIR MASS BUT ALSO ABUNDANT SUNSHINE
AND SLIGHT DOWNSLOPING...A BLEND OF MOS AND RAW TEMPS IS APPROPRIATE
WHICH CONTINUES TO SUPPORT TEMPS A COUPLE CATEGORIES BELOW NORMAL
EXCEPT IN THE HIGH TERRAIN WHERE MANY AREAS WON/T RISE OUT OF THE
30S. TONIGHT...WINDS BECOME LIGHT AND SKIES REMAIN CLEAR AND LOWS
DROP INTO THE TEENS MTNS AND 20S PIEDMONT.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
AS OF 200 AM WEDNESDAY...A DRY COLD FRONT WILL CROSS THE REGION
DURING THE DAY ON THURSDAY...LOWERING DEWPOINTS EVEN FURTHER. WITH
BREEZY TO WINDY CONDITIONS OVER THE NC MTNS AND FOOTHILLS...THE
POTENTIAL EXITS FOR CRITICAL FIRE WEATHER CONDITIONS. PLEASE SEE THE
FIRE WEATHER PART OF THE DISCUSSION FOR MORE DETAILS.
OTHERWISE...DRY COLD AIR DAMMING WILL BECOME MORE PRONOUNCED OVER
THE REGION THURSDAY NIGHT AND FRIDAY. THE THICKNESS TROUGH IN THE
LEE SHOULD RESULT IN COLD CONDITIONS THU NIGHT AND WELL BELOW
NORMAL TEMPERATURES ON FRIDAY. THURSDAY WE SHOULD SEE CLEAR...BLUE
SKIES. SKIES REMAIN CLEAR THU NIGHT...BUT HIGH CLOUDS SHOULD BE ON
THE INCREASE DURING THE DAY ON FRIDAY. A FAST MOVING SHORT WAVE WILL
CROSS THE NC ZONES FRI NIGHT. MOST OF THE FORCING WITH THE WAVE
PASSES NORTH OF THE FORECAST AREA. HOWEVER...LLVL WARM ADVECTION
OVER THE WRN PIEDMONT MAY SUPPORT SOME PATCHY LIGHT PCPN OVER THE
ERN ZONES. THERE ALSO APPEARS TO BE SUFFICIENT FORCING ACROSS THE
MTNS TO SUPPORT CHANCE POPS AS WELL. I USED THE BOURGOUIN TECHNIQUE
WHICH STARTS PCPN AS RAIN EARLY FRIDAY NIGHT WITH A TRANSITION TO
SNOW AND THEN FREEZING RAIN OVER MOST OF THE NC ZONES. UNDERSTAND
THAT QPF IS VERY LIGHT WITH THIS EVENT AND POPS ARE GENERALLY IN THE
LOW CHANCE TO SLIGHT CHANCE RANGE. THAT/S TO SAY...THE WEATHER GRID
LOOKS SCARIER THAN THE REALITY OF THE SITUATION. STILL...WE COULD
SEE A LIGHT ACCUMULATION OF SNOW OR ICE NORTH OF I40 AND OVER PARTS
OF THE NC MTNS FRIDAY NIGHT...BUT THE PCPN IS SO LIGHT I DON/T EVEN
PLAN TO MENTION IT IN THE HWO ATTM.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AS OF 230 AM EST WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z
ON SUNDAY WITH WHATS LEFT OF AN UPPER SHORTWAVE MOVING OUT OVER THE
ATLANTIC AND UPPER RIDGING BUILDING OVER THE GULF OF MEXICO AND SE
CONUS. THE LONG RANGE MODELS ARE TRYING TO CLOSE OFF AN H5 LOW OVER
EXTREME SOUTHERN BRITISH COLUMBIA EARLY SUNDAY WITH THE NEWER RUN OF
THE GFS BEING MORE PRONOUNCED. AS WE MOVE INTO MONDAY...HEIGHTS
BEGIN TO LOWER AGAIN AS A COMPLEX UPPER TROF PATTERN MOVES SE ACROSS
THE FAR NORTHERN PLAINS AND INTO THE GREAT LAKES REGION. THE MODELS
INDICATE THAT THE MAIN TROF AXIS WILL LIKELY BE NORTH OF THE
CAROLINAS BY LATE TUES/EARLY WED AND PERSIST OVER THE REGION THRU
DAY 7. OVERALL...THE LONG RANGE MODELS APPEAR TO BE COMING INTO
BETTER AGREEMENT WRT THE PROGRESSION AND TIMING OF THIS UPPER TROF
SYSTEM...WITH THE GFS BEING MORE AMPLIFIED AND BRINGING THE SYSTEM
FARTHER SOUTH COMPARED TO THE ECMWF.
AT THE SFC...THE HIGH CENTERED OVER NEW ENGLAND HELPING TO PRODUCE A
COLD AIR WEDGE PATTERN OVER THE CAROLINAS WILL BE MOVING WELL OFF
THE COAST BY EARLY SUN. THE MODELS CONTINUE TO MAINTAIN ANOTHER
BERMUDA TYPE HIGH CENTERED TO OUR EAST ON SUN AND EARLY MON. THEY
ALSO SPIN UP A LOW OVER THE SOUTHERN MISS RIVER VALLEY EARLY MON AND
MOVE IT OVER THE CWFA BY MON AFTERNOON. WHAT HAPPENS OVER THE NEXT
24 TO 36HRS VARIES CONSIDERABLY BETWEEN THE GFS AND ECMWF. THE GFS
KEEPS THE LOW AND ITS ASSOCIATED REGION OF BROAD AND DEEP MOISTURE
OVER THE FCST AREA THRU TUES AFTERNOON BEFORE MOVING IT NE AND
OFFSHORE...WHILE THE ECMWF AND CMC MOVE IT OFFSHORE BY MON EVENING
WITH DRIER HIGH PRESSURE SPREADING OVER THE REGION IN ITS WAKE ON
TUES. BOTH MODELS AGREE THAT THE REMAINDER OF THE FCST SHOULD BE DRY
HIGH PRESSURE OVER THE AREA ON WED. TEMPS WILL START OUT WELL ABOVE
NORMAL FOR EARLY MARCH WITH HIGHS ON SUN IN THE MID 60S FOR THE
LOWER ELEVATIONS AND UPPER 50S TO LOW 60S FOR THE HIGHER TERRAIN. BY
THE END OF THE PERIOD...I ANTICIPATE THAT VALUES WILL COOL BACK DOWN
BELOW CLIMATOLOGY.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...LOW VFR CLOUDINESS LINGERS THIS MRNG IN WARM UPGLIDE PRIOR
TO ARRIVAL OF COLD FRONT. PRECIP CHANCES DUE TO THE UPGLIDE ARE
LOW...WITH SHORT TERM GUID KEEPING MOST OF THE RESPONSE WELL SOUTH.
A FEW SPRINKLES OR BRIEF -SHRA ARE POSSIBLE THRU MID MRNG...BUT
WITHOUT RESTRICTIONS. MAINLY NE WINDS PRIOR TO THE FROPA...POSSIBLY
KEPT CLOSER TO 090 DUE TO LEE TROUGHING. NW WINDS AND CLEARING SKIES
BY MIDDAY POST FROPA. SKC LIKELY OVERNIGHT...BUT NAM/GFS BOTH TRY TO
DEVELOP SOME SPOTTY LOW VFR CLOUDS DUE TO LLVL CONVERGENCE IN THE
LEE OF THE MTNS. THIS IS A BIT UNUSUAL AND IS NOT BACKED UP BY MOS
SO WILL NOT REFLECT IN TAF.
ELSEWHERE...PRECIP CHANCES THIS AM ARE TOO LOW TO MENTION EXCEPT AT
KAND...WHICH WILL BE NEARER THE BEST LIFT/MSTR ASSOCIATED WITH WARM
ADVECTION OVER THE DEEP SOUTH. CIGS LIKELY TO STAY LOW VFR AT
WORST...BUT WILL MONITOR UPSTREAM OBS FOR LOWER CIGS WHICH MIGHT BE
ASSOCIATED WITH PRECIP. NW FLOW INTO THE MTNS WILL PRODUCE A FEW
-SHSN BUT THESE SHOULD BE VERY LIGHT AND MAY NOT CAUSE SGFNT
REDUCTION IN VSBY. EXCEPT AT KAVL WHICH REMAINS NW...NELY WINDS WILL
PREVAIL UNTIL THE FRONT PASSES AND SKIES GRADUALLY CLEAR. POST FROPA
WINDS WILL MAINLY BE NW BEFORE VEERING TONIGHT.
OUTLOOK...DRY/VFR THU-FRI...BUT PRECIPITATION AND ASSOCIATED
RESTRICTIONS ARE POSSIBLE EARLY SAT.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-11Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.FIRE WEATHER...
A MODIFIED ARCTIC AIR MASS WILL RESULT IN DEWPOINTS IN THE SINGLE
DIGITS AND TEENS THIS AFTERNOON AND AGAIN THU AFTERNOON. WITH A
RELATIVELY COOL AIR MASS IN PLACE...RH IS EXPECTED TO DIP TO 25
PERCENT OR LESS ONLY BRIEFLY TODAY. MEANWHILE...GUSTY MORNING WINDS
SHOULD BEGIN TO DIMINISH BY AFTERNOON. AT THIS TIME...THE GUSTY
WINDS AND LOWEST RH ARE NOT EXPECTED TO OVERLAP TODAY.
HOWEVER...AS THE AIR MASS BEGINS TO WARM ON THURSDAY...RH IS
EXPECTED TO FALL BELOW 20 PERCENT IN MOST AREAS DURING THE
AFTERNOON. IN ADDITION... W/NW WINDS WILL BEGIN TO INCREASE AHEAD OF
ANOTHER DRY COLD FRONT DURING THE AFTERNOON. WINDS MAY GUST AS HIGH
AS 30 MPH IN THE MTNS...AND TO AROUND 20 MPH IN THE PIEDMONT.
CRITICAL WIND AND RH MAY OVERLAP FOR SEVERAL HOURS ACROSS THE MTNS
AND NC FOOTHILLS THU AFTERNOON.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...WIMBERLEY
SHORT TERM...MCAVOY
LONG TERM...JPT
AVIATION...WIMBERLEY
FIRE WEATHER...MCAVOY
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
536 AM CST WED FEB 26 2014
.DISCUSSION...
SEE 12Z AVIATION DISCUSSION.
&&
.AVIATION...
FIRST S/WV IS EXITING THE AREA AND WILL TAKE A BULK OF THE
RAINFALL WITH IT. A SECOND S/WV WILL BE APPROACHING THE AREA LATER
THIS MORNING BUT IT APPEARS THAT MOST OF THE PRECIP WILL TARGET
THE SOUTHERN TAF SITES. STILL SOME UNCERTAINTY WITH REGARD TO
REDEVELOPMENT AS THE RAP/NAM AND ECMWF ARE CONSIDERABLY DRIER THAN
THE GFS. MAINLY MVFR CIGS ARE EXPECTED TODAY WITH PERIODS OF IFR.
VFR CONDS EXPECTED TO DEVELOP OVERNIGHT WITH VFR CONDS EXPECTED ON
THURSDAY. WINDS WILL BE GUSTY THIS MORNING WITH SPEEDS DECREASING
IN THE AFTN AND DECOUPLING TO NEAR CALM OVERNIGHT. 43
&&
.PREV DISCUSSION... /ISSUED 453 AM CST WED FEB 26 2014/
DISCUSSION...
THE RADAR HAS FILLED IN NICELY THIS MORNING WITH SOME ISOLATED
THUNDER NORTH OF INTERSTATE 10. THIS RAINFALL IS THE RESULT OF A
PASSING SURFACE COLD FRONT IN COMBINATION WITH MULTIPLE UPPER
LEVEL DISTURBANCES MOVING ACROSS THE AREA. THE COLD FRONT HAS NOW
MOVED OFFSHORE WITH TEMPERATURES FALLING IN ITS WAKE. A HAND
ANALYSIS AT 250MB FROM 0Z THIS MORNING STILL SHOWS THE SUBTROPICALJET
WITH AN UNFAVORABLE ANTICYCLONIC CURVATURE TO IT. THE JET IS
FORECASTED TO FLATTEN THOUGH AND ALLOW SOUTHEAST TEXAS TO FALL
BRIEFLY INTO A RRQ THIS MORNING INTO EARLY AFTERNOON BEFORE
EXITING THE AREA THIS EVENING.
ANOTHER ROUND OF RAIN HAS STARTED TO FIRE OUT NEAR THE DEL RIO
AREA AND IS ALSO A RESULT OF A PASSING UPPER LEVEL DISTURBANCE.
THE DISTURBANCE IS FORECASTED TO MOVE TO THE EAST DURING THE DAY
TODAY AND BRING SOME MORE RAINFALL TO THE AREA THIS AFTERNOON. GFS
AND NAM OMEGA FIELDS HINT AT THE SOUTHERN HALF OF THE AREA TO BE
THE MOST LIKELY SPOT FOR THE RAINFALL THIS AFTERNOON. THE HRRR AND
TEXAS TECH WRF WOULD ALSO TEND TO AGREE WITH THIS. MODELS ARE ALSO
INDICATING THE POSSIBILITY OF SOME LIGHT STRATIFORM RAIN THROUGH
THE WASHINGTON... MONTGOMERY... SAN JACINTO COUNTY AREA. ONLY
CONCERN WITH THIS SOLUTION IS THAT BOTH GFS AND NAM MODEL
SOUNDINGS SHOW DRY AIR WORKING ITS WAY SOUTH IN THE 850 TO 700MB
LAYER.
TEMPERATURES WILL BE HOLDING STEADY OR DROPPING THROUGH
THE DAY TODAY AS SURFACE HIGH PRESSURE SETTLES OVERHEAD. MODELS
ARE ALSO HINTING AT THE CLOUDS TRYING TO BREAK BY THURSDAY
MORNING. THIS IN COMBINATION WITH LIGHT WINDS WILL MAKE THURSDAY
MORNING COLD. ON FRIDAY A SHORTWAVE WILL MOVE TO THE SOUTHEAST AND
CROSS THE TEXARKANA AREA FRIDAY AFTERNOON. BOTH GFS AND NAM
SOUNDINGS LOOK TO HAVE A SIZABLE CAP IN PLACE AROUND THIS TIME
WHICH WOULD TEND TO INHIBIT THUNDERSTORM DEVELOPMENT. ISOLATED
SHOWERS COULD BE POSSIBLE IN OUR NORTHEASTERN ZONES BUT CHANCES
LOOK LOW AS OF NOW.
AN UPPER LEVEL LOW WILL MOVE INTO SOUTHERN CALIFORNIA SATURDAY
AFTERNOON AND BEGIN TO SHEAR OUT AS IT PROGRESSES EASTWARDS. THE
ECMWF AND CANADIAN REMAIN MORE PROGRESSIVE WITH THE FEATURE WHILE
THE GFS HOLDS THE SHORTWAVE UP A BIT. IF THE GFS IS RIGHT A
SURFACE COLD FRONT WILL ALSO BE HELP UP UNTIL LATE MONDAY MORNING.
THE ECMWF AND CANADIAN FAVOR THE COLD FRONT MAKING IT LATE SUNDAY
EVENING OR EARLY MONDAY MORNING. GFS AND ECMWF SOUNDINGS BOTH
SUPPORT SHOWERS AND THUNDERSTORMS WITH THIS FRONT. FOR NOW HAVE
LEANED TOWARDS THE ECMWF AND CANADIAN SOLUTION. 23
MARINE...
SEA FOG HAS ERODED AS STRONG NORTH WINDS DEVELOP IN THE WAKE OF A
DEPARTING COLD FRONT. A TIGHT PRESSURE GRADIENT WILL PRODUCE STRONG
NORTH WINDS THROUGH THE DAY. WILL MAINTAIN AN SCA FOR ALL WATERS
THROUGH 18Z AND THEN THE GULF WATERS THROUGH 00Z. THE GRADIENT WILL
RELAX TONIGHT AS HIGH PRESSURE NEARS THE NORTHERN GULF COAST. THE
HIGH WILL DRIFT EAST AND ONSHORE WINDS WILL RETURN ON THURSDAY AND
PERSIST THROUGH THE WEEKEND. COULD BE ANOTHER BRIEF EPISODE OF SEA
FOG ON SUNDAY. THE NEXT COLD FRONT WILL CROSS THE COASTAL WATERS
LATE SUNDAY NIGHT OR EARLY MONDAY. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 44 32 57 43 70 / 50 20 10 10 10
HOUSTON (IAH) 49 35 59 44 69 / 50 30 10 10 10
GALVESTON (GLS) 54 41 55 53 66 / 60 40 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM NOON CST TODAY THROUGH
THIS AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
MATAGORDA BAY.
SMALL CRAFT ADVISORY UNTIL 6 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM THIS EVENING THROUGH
LATE TONIGHT FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION LATE TONIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...23
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
453 AM CST WED FEB 26 2014
.DISCUSSION...
THE RADAR HAS FILLED IN NICELY THIS MORNING WITH SOME ISOLATED
THUNDER NORTH OF INTERSTATE 10. THIS RAINFALL IS THE RESULT OF A
PASSING SURFACE COLD FRONT IN COMBINATION WITH MULTIPLE UPPER
LEVEL DISTURBANCES MOVING ACROSS THE AREA. THE COLD FRONT HAS NOW
MOVED OFFSHORE WITH TEMPERATURES FALLING IN ITS WAKE. A HAND
ANALYSIS AT 250MB FROM 0Z THIS MORNING STILL SHOWS THE SUBTOPICAL
JET WITH AN UNFAVORABLE ANTICYCLONIC CURVATURE TO IT. THE JET IS
FORECASTED TO FLATTEN THOUGH AND ALLOW SOUTHEAST TEXAS TO FALL
BRIEFLY INTO A RRQ THIS MORNING INTO EARLY AFTERNOON BEFORE
EXITING THE AREA THIS EVENING.
ANOTHER ROUND OF RAIN HAS STARTED TO FIRE OUT NEAR THE DEL RIO
AREA AND IS ALSO A RESULT OF A PASSING UPPER LEVEL DISTURBANCE.
THE DISTURBANCE IS FORECASTED TO MOVE TO THE EAST DURING THE DAY
TODAY AND BRING SOME MORE RAINFALL TO THE AREA THIS AFTERNOON. GFS
AND NAM OMEGA FIELDS HINT AT THE SOUTHERN HALF OF THE AREA TO BE
THE MOST LIKELY SPOT FOR THE RAINFALL THIS AFTERNOON. THE HRRR AND
TEXAS TECH WRF WOULD ALSO TEND TO AGREE WITH THIS. MODELS ARE ALSO
INDICATING THE POSSIBILITY OF SOME LIGHT STRATIFORM RAIN THROUGH
THE WASHINGTON... MONTGOMERY... SAN JACINTO COUNTY AREA. ONLY
CONCERN WITH THIS SOLUTION IS THAT BOTH GFS AND NAM MODEL
SOUNDINGS SHOW DRY AIR WORKING ITS WAY SOUTH IN THE 850 TO 700MB
LAYER.
TEMPERATURES WILL BE HOLDING STEADY OR DROPPING THROUGH
THE DAY TODAY AS SURFACE HIGH PRESSURE SETTLES OVERHEAD. MODELS
ARE ALSO HINTING AT THE CLOUDS TRYING TO BREAK BY THURSDAY
MORNING. THIS IN COMBINATION WITH LIGHT WINDS WILL MAKE THURSDAY
MORNING COLD. ON FRIDAY A SHORTWAVE WILL MOVE TO THE SOUTHEAST AND
CROSS THE TEXARKANA AREA FRIDAY AFTERNOON. BOTH GFS AND NAM
SOUNDINGS LOOK TO HAVE A SIZABLE CAP IN PLACE AROUND THIS TIME
WHICH WOULD TEND TO INHIBIT THUNDERSTORM DEVELOPMENT. ISOLATED
SHOWERS COULD BE POSSIBLE IN OUR NORTHEASTERN ZONES BUT CHANCES
LOOK LOW AS OF NOW.
AN UPPER LEVEL LOW WILL MOVE INTO SOUTHERN CALIFORNIA SATURDAY
AFTERNOON AND BEGIN TO SHEAR OUT AS IT PROGRESSES EASTWARDS. THE
ECMWF AND CANADIAN REMAIN MORE PROGRESSIVE WITH THE FEATURE WHILE
THE GFS HOLDS THE SHORTWAVE UP A BIT. IF THE GFS IS RIGHT A
SURFACE COLD FRONT WILL ALSO BE HELP UP UNTIL LATE MONDAY MORNING.
THE ECMWF AND CANADIAN FAVOR THE COLD FRONT MAKING IT LATE SUNDAY
EVENING OR EARLY MONDAY MORNING. GFS AND ECMWF SOUNDINGS BOTH
SUPPORT SHOWERS AND THUNDERSTORMS WITH THIS FRONT. FOR NOW HAVE
LEANED TOWARDS THE ECMWF AND CANADIAN SOLUTION. 23
&&
.MARINE...
SEA FOG HAS ERODED AS STRONG NORTH WINDS DEVELOP IN THE WAKE OF A
DEPARTING COLD FRONT. A TIGHT PRESSURE GRADIENT WILL PRODUCE STRONG
NORTH WINDS THROUGH THE DAY. WILL MAINTAIN AN SCA FOR ALL WATERS
THROUGH 18Z AND THEN THE GULF WATERS THROUGH 00Z. THE GRADIENT WILL
RELAX TONIGHT AS HIGH PRESSURE NEARS THE NORTHERN GULF COAST. THE
HIGH WILL DRIFT EAST AND ONSHORE WINDS WILL RETURN ON THURSDAY AND
PERSIST THROUGH THE WEEKEND. COULD BE ANOTHER BRIEF EPISODE OF SEA
FOG ON SUNDAY. THE NEXT COLD FRONT WILL CROSS THE COASTAL WATERS
LATE SUNDAY NIGHT OR EARLY MONDAY. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 44 32 57 43 70 / 50 20 10 10 10
HOUSTON (IAH) 49 35 59 44 69 / 50 30 10 10 10
GALVESTON (GLS) 54 41 55 53 66 / 60 40 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL NOON CST TODAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM NOON CST TODAY THROUGH
THIS AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
MATAGORDA BAY.
SMALL CRAFT ADVISORY UNTIL 6 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT
20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION FROM THIS EVENING THROUGH
LATE TONIGHT FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION LATE TONIGHT FOR THE
FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...23
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS SPOKANE WA
258 AM PST Wed Feb 26 2014
.SYNOPSIS...
Dry weather is expected today with a little bit of warming for
most locations. The dry lull in the weather will come to an end on
Thursday. With warmer temperatures expected, rain will be the
primary precipitation type. A return of colder weather is
expected Friday night into Saturday with a good chance of snow for
most locations. Meanwhile much colder air will return for the
weekend with Daytime temperatures this weekend with readings in
the teens to middle 20s. Breezy winds will make it feel even
colder especially over portions of the North Idaho Panhandle.
&&
.DISCUSSION...
Today through tonight...Latest satellite images would suggest we
are looking at a fairly quiet day as 500 mb ridge will remain
fixed over the region. The main focus will revolve around
negatively tilted trough axis and warm front currently pushing
through SW Oregon. The main impact this feature will have on our
forecast area today will be a slowly increasing cloud trend from
the southwest. Despite this increasing cloud trend, there really
is little of any threat of precipitation. The main weather story
will thus revolve around the tricky temperature forecast. The
region remains split between a cool and very dry air mass fixed
over the northern 2/3rds of Washington and most of the Idaho
Panhandle. Meanwhile...a warmer and more moisture laden atmosphere
lingers over extreme SE Washington and adjacent portions of the
Idaho Panhandle. These locations...including Lewiston and Pullman
were seeing dewpoints around 30 degrees with similarly mild
temperatures. Meanwhile the remainder of the forecast area was
seeing dewpoint readings in the mid teens to single digits and
cooler temperatures. The main challenge is will this milder air to
our south retake most of the forecast area through the day as the
front moves in from the south. Certainly the models are consistent
on bringing significant warming to the 850-700 mb layer...but will
this translate to the ground. Not confident it will as the surface
pressure gradients will likely keep most of the winds out of the
north to northeast...which isn`t real favorable for significant
warming....despite the warming aloft. If the winds were strong
enough this warming aloft would readily mix to the ground...but
surface wind guidance is generally fairly weak today. We will
hedge our forecasts toward the cooler guidance solutions by
generally keep highs a little warmer than what we experienced
yesterday.
For tonight...the shortwave trough and associated front continue
to drift across the forecast area from the southwest but it
weakens significantly as it does. Whether or not the front will
have enough juice and lifting by the time it moves into our region
is the question. Models are all over the board with this feature
as far as precipitation goes...however most would agree that if
precipitation were to occur the best chances would occur near the
Cascades due the proximity of the offshore trough. This would lead
to the best moisture availability as well as the best upslope flow
and isentropic ascent. If anything does occur it should be
light...with better chances arriving after sunrise Thursday. fx
Thursday through Tuesday: Fairly low confidence in the forecast.
By Thursday the ridge is breaking down with a closed low moving
into Southern Oregon. This will bring an increased chance of
precipitation across southern WA and central ID on Thursday.
Meanwhile an arctic front will be nearing north ID. By Friday it
will be the convergence of two systems. The moist system from the
south colliding with the arctic air from Canada. Models are differing
on precipitation location and amounts, and it could vary greatly
depending on where they converge. Have increased chance of precip
across southeastern WA and the southern ID Panhandle for now, but
higher chances of precip may need to be brought further north. Snow
levels will lower through the day. Looks like the northern zones
will start and remain as snow, and the southern zones starting out
with snow levels btwn 3-4k ft and then lowering down to near the
valley floors by late afternoon/early evening. Lets not forget the
winds either. By Friday afternoon we get a very strong northeast to
southwest gradient which will create breezy to windy northeast winds
for the Purcell Trench, the Spokane/COE area, and down into portions
of the Palouse and Columbia Basin through at least early Sunday
morning. This arctic front is quite different from "normal" dry
arctic intrusions we see. This one will have lots of moisture around
to keep at least a slight chance of snow in the forecast through the
weekend. Have lowered temperatures as well, but not going as cold as
we could possibly see because am expecting more cloud cover than
what we would normally see. The cold air will remain over the area
through Monday, though it will have moderated a bit by Monday.
Monday into Tuesday we get a broad ridge building into the area with
warmer temperatures inching towards us. There doesn`t seem to be
anything to really scour out the cold temps however so keep
temperatures well below average for this time of the year. /Nisbet
&&
.AVIATION...
12Z TAFS: Low clouds with MVFR cigs will likely persist through at
least through 19z and perhaps longer for PUW and LWS. Satellite
imagery shows clouds actually expanding which suggests they may last
longer than previously anticipated despite the light downslope east
winds. The latest HRRR clears the clouds after 19z...but this is a
typical diurnal trend the model has and typically does not handle
low level moisture all that well. We went with a clearing trend a
little later than model suggests but confidence is not high. The
other question is will these MVFR cigs make their way north to GEG
SFF and COE. Low level gradients out of the NE suggest they will
remain south of the airports...but this needs to be watched as the
cloud deck slowly expands into the wind. Other than these
issues...look for cloudy skies and slowly lowering cigs at all sites
through fcst period. Condtions will generally remain VFR though. fx
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 35 25 39 29 34 10 / 0 10 20 30 50 30
Coeur d`Alene 35 27 40 27 32 10 / 0 10 20 30 50 30
Pullman 40 32 42 33 39 17 / 0 10 40 50 60 50
Lewiston 46 35 47 37 46 27 / 10 20 50 60 50 50
Colville 39 25 42 29 39 15 / 0 10 10 20 30 20
Sandpoint 36 23 40 25 31 11 / 0 0 10 30 50 20
Kellogg 38 28 39 28 31 8 / 0 20 40 60 70 50
Moses Lake 41 28 45 33 43 23 / 0 10 20 30 30 20
Wenatchee 37 28 44 33 41 25 / 10 10 20 20 40 30
Omak 36 22 40 30 39 21 / 0 0 10 20 30 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
920 AM PST WED FEB 26 2014
.UPDATE...
LOWERED TEMPERATURES FOR TODAY.
&&
.SYNOPSIS...
AN UNSETTLED WEATHER PATTERN WILL CONTINUE. RAIN AND HIGHER
ELEVATION SNOW ARE EXPECTED AT TIMES THROUGH AT LEAST THE
WEEKEND. THE NEXT SYSTEM WILL MOVE INTO THE AREA ON FRIDAY AND
SATURDAY WITH BETTER CHANCES OF PRECIPITATION ACROSS THE REGION
AND EVEN A FEW THUNDERSTORMS.
&&
.DISCUSSION...
INCREASING CLOUDS WILL REDUCE HEATING TODAY. RAIN HAS REACHED
SOUTH BAKERSFIELD AT THIS TIME...AND THE RAIN WILL SUPPRESS THE
SOUTHERLY SURFACE FLOW. TEMPERATURES HAVE BEEN LOWERED OVER THE
REGION AND ARE NOW CLOSER TO 12Z GUIDANCE. POPS HAVE BEEN RAISED
FOR THE SOUTH END OF THE SAN JOAQUIN VALLEY DUE TO EARLIER ARRIVAL
OF PRECIPITATION.
&&
.AVIATION...
INCREASING CLOUDS WITH GRADUALLY LOWERING CEILINGS...AREAS OF MVFR
AND LOCAL IFR CONDITIONS DEVELOPING IN PRECIPITATION SPREADING IN
FROM THE WEST AFTER 18Z WEDNESDAY ACROSS THE CENTRAL CA INTERIOR.
&&
.PREV DISC... /ISSUED 846 AM PST WED FEB 26 2014/
DISCUSSION...125 KT JET THAT IS UNDERCUTTING OFFSHORE STORM IS
PUSHING COLD FRONT AND ASSOCIATED RAIN BAND MORE QUICKLY EASTWARD
THAN ORIGINALLY ANTICIPATED. THE GFS AND HRRR MODELS SEEM TO HAVE
A MUCH BETTER HANDLE ON THIS SO WILL USE THESE SOLUTIONS FOR GUIDANCE.
ALTHO SW WINDS HAVE DIMINISHED SOMEWHAT ON THE WEST SIDE OF THE SJ
VLY...THERE WILL BE LOCAL GUSTS TO 40 MPH FOR THE NEXT HR OR SO.
HOWEVER...THE ONSET OF RAIN WILL STABILIZE WINDS IN THIS PORTION
OF THE CWA TODAY. REMAINDER OF FORECAST LOOKS ON TRACK.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 02-26 83:1888 44:1962 53:1995 25:1971
KFAT 02-27 79:1992 45:1996 54:2006 26:1962
KFAT 02-28 79:1926 51:1971 59:1986 28:1962
KBFL 02-26 80:1992 43:1962 56:1968 30:1971
KBFL 02-27 83:1980 46:1962 58:1988 24:1893
KBFL 02-28 81:1926 49:1945 56:1968 22:1893
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 4 PM PST THURSDAY ABOVE 7000 FEET
FOR THE SOUTHERN SIERRA NEVADA FROM YOSEMITE TO THE KERN COUNTY
LINE /CAZ096-097/.
WINTER STORM WATCH FROM LATE THURSDAY NIGHT THROUGH LATE
SATURDAY NIGHT ABOVE 6000 FEET FOR THE SOUTHERN SIERRA NEVADA FROM
YOSEMITE TO THE KERN COUNTY LINE /CAZ096-097/.
HIGH WIND WATCH FROM THURSDAY EVENING THROUGH FRIDAY AFTERNOON FOR
THE KERN COUNTY MOUNTAINS...MAINLY NEAR THE GRAPEVINE /CAZ095/.
WIND ADVISORY UNTIL NOON PST TODAY FOR THE WEST SIDE OF THE SAN
JOAQUIN VALLEY /CAZ089-091/.
&&
$$
PUBLIC...SANGER
AVN/FW...DURFEE
PREV DISCUSSION...DURFEE
SYNOPSIS...BSO
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS ALBANY NY
1248 PM EST WED FEB 26 2014
.SYNOPSIS...
A CLIPPER LOW CONTINUES TO MOVE ACROSS SOUTHERN QUEBEC THIS
AFTERNOON...AS ITS COLD FRONT MOVES THROUGH NEW ENGLAND WITH A
REINFORCING SHOT OF ARCTIC AIR BEHIND IT. ANOTHER CLIPPER WILL BRING
A CHANCE OF MORE SNOW SHOWERS AND SNOW SQUALLS ON THURSDAY WITH SOME
BITTERLY COLD AIR FOR EASTERN NEW YORK AND WESTERN NEW ENGLAND
THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1233 PM EST...CLIPPER TYPE LOW CONTINUES TO MOVE ACROSS SRN
QUEBEC TOWARDS NRN ME AND NEW BRUNSWICK. THE COLD FRONT HAS MOVED
THROUGH WITH DIFFUSE SNOW SHOWERS AND FLURRIES...ASIDE FROM A LAKE
EFFECT SNOWBAND COMING OFF LAKE ONTARIO INTO THE TUG HILL PLATUEAU
INTO THE WRN DACKS AND MOST SPECIFICALLY NRN HERKIMER CO. THE
INLAND EXTENT HAS BEEN DIFFICULT DOWNSTREAM. THE LAKE EFFECT SNOW
ADVISORY REMAINS IN EFFECT FOR HERKIMER CO...BUT WE MAY DROP SRN
HERKIMER WITH THE NEXT UPDATE...AS THE 260-270 DEG TRAJECTORY
FAVORS NRN HERKIMER. THE LATEST HRRR GUIDANCE SHOWS THE BAND
WEAKENING BY THIS EVENING AND LIFTING NORTHWARD. WE ALSO LOWERED
AMOUNTS TO 3 TO 6 INCHES FOR THE AREA. MOST OF THE SCT SNOW
SHOWERS PRODUCED LESS THAN AN INCH OF SNOW. PLEASE SEE OUR LATEST
PNS...WITH ISOLD HIGHER AMOUNTS. TEMPS LOOKS ON TRACK WITH BRISK
CONDITIONS AND HIGHS A SOLID 10 TO 15 DEGREES BELOW NORMAL.
H850 TEMPS CRASH AGAIN TO -19C TO -22C OVER THE FCST AREA BY THE
LATE PM. IT WILL ALSO BECOME WINDY IN THE WAKE OF THE FRONT WITH
UPSLOPE SNOW SHOWERS POSSIBLE OVER THE TACONICS...BERKSHIRES...AND
SRN GREENS. IN ADDITION TO LAKE EFFECT SNOWS THERE IS THE
SLIGHT POSSIBILITY OF A WINDEX TYPE EVENT IN THE WAKE OF THE
ARCTIC FRONT AS RH VALUES IN THE LOWER LEVELS ARE GREATER THAN 70
PERCENT AND T1-T5 LAYER TEMPS DIFFER BY MORE THAN 10 C. IT WILL BE
VERY CHILLY TODAY WITH HIGHS ONLY RANGING FROM THE LOW TO MID
TEENS NORTHWEST TO THE LOW TO MID 20S SOUTHEAST.
TONIGHT....BLUSTERY CONDITIONS WILL PERSIST THROUGH THE EVENING
HOURS AND THE LAKE EFFECT BAND WILL COME TO AN END AS A WEAK RIDGE
OF HIGH PRESSURE BUILDS IN FROM THE SOUTH AHEAD OF THE NEXT
CLIPPER TYPE SYSTEM WHICH WILL ALREADY BE MOVING INTO THE SE
ONTARIO AND THE ERN GREAT LAKES REGION BY LATE TONIGHT. WIND CHILL
VALUES WILL BE CLOSE TO ADVISORY CRITERIA AND MAINLY ACROSS THE
WESTERN ADIRONDACKS. OVERNIGHT LOWS ARE EXPECTED TO RANGE FROM 10
BELOW TO 5 ABOVE ZERO.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
THU-THU NIGHT....THE SECOND CLIPPER TYPE SYSTEM IMPACTS THE FA AS
IT MOVES ACROSS SOUTHERN QUEBEC...NRN NY AND NRN NEW ENGLAND
SWINGING ANOTHER ARCTIC COLD FRONT THROUGH OUR REGION. THIS
SYSTEM IS EVEN STRONGER THAN THE FIRST CLIPPER TYPE SYSTEM AND
LOOKS TO SET UP A CLASSIC WINDEX EVENT IN THE WAKE OF THE COLD
FRONT WHICH WILL BE ENHANCED BY A SECONDARY TROUGH OF LOW PRESSURE.
THE BEST MOISTURE CONVERGENCE LOOKS LIKE IT WILL BE OVER THE WRN
DACKS AGAIN...WHERE A FEW INCHES OF SNOW LOOK LIKELY. MOST OTHER
LOCATIONS WILL RECEIVE A DUSTING TO AN TWO INCHES. THE WIND FIELDS
STRENGTHEN IN THE WAKE OF THE CLIPPER WITH SW WINDS SHIFTING TO
THE WEST WITH THE FRONTAL PASSAGE IN THE AFTERNOON. WEST WINDS OF
15 TO 25 MPH WITH SOME GUSTS TO 35 TO 40 MPH WILL BE POSSIBLE DUE
TO FUNNELING DOWN THE MOHAWK VALLEY INTO THE CAPITAL REGION INTO
THE CNTRL TACONICS...AND BERKSHIRES. THESE GUSTY WINDS ARE ALSO
EXPECTED IN THE ERN AND NRN CATSKILLS. HIGHS ON THURSDAY WILL
GENERALLY BE IN THE UPPER TEENS TO UPPER 20S. LOWS THURSDAY NIGHT
WILL BE IN THE 10 BELOW ZERO TO 5 ABOVE ZERO RANGE WITH WIND CHILL
VALUES REACHING ADVISORY CRITERIA ACROSS SOME OF THE HIGHER
TERRAIN.
FRIDAY AND FRIDAY NIGHT HIGH PRESSURE WILL PROVIDE PLENTY OF
SUNSHINE TO THE REGION ALTHOUGH IT WILL STILL BE VERY COLD AND
BLUSTERY. EXPECT HIGH ON FRIDAY TO BE IN THE TEENS TO AROUND 20
WITH PERHAPS ONLY SINGLE DIGITS ACROSS PORTIONS OF THE WESTERN
ADIRONDACKS. LOWS FRIDAY NIGHT WILL BE IN THE 10 BELOW TO 5 ABOVE
ZERO RANGE ONCE AGAIN.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
BELOW TO MUCH BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE
LONG TERM PORTION OF THE FORECAST. IN ADDITION...THE POTENTIAL FOR
STORMINESS WILL INCREASE...ESP BY SUN NT-MON...AS SHORTWAVE ENERGY
ORIGINATING OVER THE SOUTHWEST U.S. EJECTS RAPIDLY
NORTHEASTWARD...AHEAD OF A LONG WAVE TROUGH PIVOTING SLOWLY E/SE
ACROSS THE NORTHERN PLAINS.
OVERALL...MODELS HAVE TRENDED SLIGHTLY SOUTHWARD WITH REGARD TO
THEIR RESPECTIVE SURFACE FEATURES COMPARED TO 24 HOURS AGO /00Z 25
RUNS/.
TAKING A LOOK AT SOME PV TRACES...IT APPEARS THAT ENERGY CURRENTLY
DIGGING SOUTHWARD WELL SOUTHWEST OF THE ALEUTIAN ISLANDS WILL BE THE
MAIN DRIVER FOR EARLY NEXT WEEK...AS THIS PV ANOMALY POSSIBLY
REACHES SOUTHERN CA EARLY THIS WEEKEND...AS THE UPPER LEVEL
TROUGH/LOW CURRENTLY FURTHER EAST SPLITS INTO TWO PIECES...ONE
TRANSLATING NORTHWARD WELL OFF THE PACIFIC NW COAST...AND ANOTHER
PIECE TRANSLATES EAST AND WEAKENS...AFFECTING OUR REGION ON
SATURDAY. THE MODELS SEEM TO HANDLE THE DIGGING ENERGY
DIFFERENTLY...WITH THE 00Z/26 ECMWF A BIT FASTER IN PROGRESSING THIS
ENERGY OUT ACROSS THE SOUTHERN PLAINS AND EVENTUALLY OHIO VALLEY FOR
SUN-MON...AND ALSO KEEPING THE ENERGY IN TACT A BIT LONGER...WHILE
THE 00Z/26 GFS IS SLOWER...AND SEEMS TO WEAKEN/SHEAR THIS ENERGY
FASTER WITH A SOMEWHAT FLATTER WAVE FOR AFFECTING THE REGION FOR
LATE MON INTO TUE. HAVE SIDED CLOSER TO THE 00Z/26 WPC/ECMWF
SOLUTIONS.
EITHER WAY...IT APPEARS THAT WARM ADVECTION WELL AHEAD OF ANY SUCH
WAVE SHOULD ALLOW CLOUDS AND PRECIP TO DEVELOP SUN NT...AND INTO
MONDAY...BEFORE POSSIBLY TAPERING OFF LATE MON NT OR TUES. BASED ON
CURRENT 00Z/26 DETERMINISTIC AND ENSEMBLE GUIDANCE...SOUTHERN
PORTIONS OF THE FORECAST AREA APPEAR TO BE MOST FAVORED FOR MODERATE
OR GREATER AMOUNTS OF PRECIPITATION...BUT AGAIN...THIS SOUTHWARD
MODEL TREND STARTED WITHIN THE LAST 24 HOURS...AND WOULD NOT BE
SURPRISED TO ULTIMATELY SEE MODELS SOLUTIONS TREND BACK SLIGHTLY
NORTHWARD AGAIN OVER THE NEXT 1-3 DAYS WITH REGARD TO THIS POTENTIAL
STORM SYSTEM.
HERE ARE SOME MORE SPECIFICS...
SAT-SUN...THE FIRST WAVE IS EXPECTED TO WEAKEN...AND TRANSLATE
RAPIDLY EAST/NORTHEAST ON SAT. A SURGE OF WEAK WARM ADVECTION SHOULD
ALLOW FOR ABUNDANT CLOUDS AND SOME LIGHT SNOW/SNOW SHOWERS TO
OVERSPREAD THE REGION LATE SAT MORNING INTO THE
AFTERNOON...ESPECIALLY FOR AREAS NEAR AND WEST OF THE HUDSON RIVER.
THE SNOW SHOWERS ARE EXPECTED TO SINK SOUTHWARD SAT NT AND EARLY
SUNDAY...AS THE ASSOCIATED ARCTIC FRONTAL BOUNDARY ALSO DROPS SOUTH.
WILL THEREFORE INDICATE CHC POPS FOR MOST AREAS FROM ALBANY N AND
W...AND MAINLY SLIGHT CHC TO THE S/E THROUGH SAT...THEN CHC POPS ALL
AREAS FOR SAT NT INTO EARLY SUN...WITH SOME LIKELY POPS FOR NW
AREAS.
THERE IS A POSSIBILITY THAT SNOW SHOWERS AND/OR AREAS OF LIGHT SNOW
ACTUALLY TAPER OFF ACROSS NORTHERN AREAS SUNDAY
AFTERNOON/EVENING...AS THE FRONT AND ASSOCIATED MID LEVEL FORCING
SHIFTS FURTHER SOUTH. WILL THEREFORE TAPER POPS IN THE AFTERNOON FOR
NORTHERN AREAS INTO THE SLIGHT CHC RANGE...WITH CHC POPS REMAINING
FOR CENTRAL AND SOUTHERN AREAS.
SUN NT-MON...THE AFOREMENTIONED SECOND WAVE SHOULD EJECT OUT OF THE
SOUTHWEST U.S...AND WILL CONTINUE TRANSLATING E/NE...ALLOWING A
LARGE AREA OF ISENTROPIC LIFT TO DEVELOP ACROSS THE REGION. THIS
SHOULD ALLOW FOR SNOW TO OVERSPREAD THE REGION SUN NT...AND CONTINUE
THROUGH MONDAY. SNOW SHOULD BE THE MAIN P-TYPE FOR MOST AREAS. BASED
ON THE SLIGHT SOUTHWARD TREND OF THE 00Z/26 MODELS WITH REGARD TO
STRONGEST MID LEVEL FORCING AND MOISTURE...HAVE ADDED LIKELY POPS
ACROSS SOUTHERN AND EASTERN PORTIONS OF THE FORECAST AREA...WITH CHC
POPS ELSEWHERE.
TEMPS WILL REMAIN BELOW TO MUCH BELOW NORMAL THROUGH THE PERIOD. THE
MILDEST DAY SHOULD BE SATURDAY...AHEAD OF THE INCOMING ARCTIC
FRONTAL BOUNDARY...WITH MAX TEMPS REACHING THE LOWER 30S IN VALLEY
AREAS...AND 20S ACROSS MOST HIGHER ELEVATIONS. FOR SAT NT/SUN
AM...AS THE ARCTIC BOUNDARY SINKS SOUTHWARD...TEMPS SHOULD FALL INTO
THE TEENS IN MOST AREAS...EXCEPT FOR SINGLE DIGITS ACROSS PORTIONS
OF THE ADIRONDACKS. ON SUNDAY...MAX TEMPS SHOULD GENERALLY ONLY
REACH THE 20S IN VALLEYS WITH TEENS ACROSS THE ADIRONDACKS. TEMPS
SHOULD THEN FALL INTO THE SINGLE DIGITS TO MID TEENS SUN NT...AND
THEN ONLY RISE INTO THE TEENS AND 20S FOR MONDAY...ALTHOUGH THERE IS
THE POTENTIAL FOR EVEN COLDER MAX TEMPS IF ENOUGH LOW LEVEL ARCTIC
AIR SEEPS SOUTHWARD INTO THE REGION IN THE WAKE OF THE WEEKEND
WAVE...AND IF SNOW FALLS INTO THIS COLD AND RELATIVELY DRY LOW LEVEL
AIR. EXPECT SINGLE DIGITS AND TEENS AGAIN FOR MON NT/TUE AM...WITH
TUE MAXES MAINLY IN THE 20S IN VALLEYS...AND TEENS ACROSS HIGHER
ELEVATIONS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
PREDOMINATELY VFR CONDITIONS WILL PREVAIL THROUGHOUT THE TAF PERIOD
WITH SCATTERED SNOW SHOWERS DIMINISHING BY THIS EVENING.
THIS AFTERNOON...WIDELY SCATTERED SNOW SHOWERS ASSOCIATED WITH A
WEAK CLIPPER AND COLD FRONT WILL CONTINUE THROUGH THE AFTERNOON
HOURS...ESPECIALLY AT KGFL WHERE SOME LAKE MOISTURE WILL ALSO BE
TAPPED. HAVE INCLUDED A TEMPO GROUP AT KGFL UNTIL 20Z TO ACCOUNT FOR
ANY BRIEF IFR REDUCTIONS IN HEAVIER SNOW SHOWERS...AND VCSH AT THE
OTHER TAF SITES DUE TO WIDELY SCATTERED NATURE OF THE SHOWERS.
WESTERLY WINDS WILL BE GUSTY THIS AFTERNOON...GUSTING 20-25 KNOTS
EXCEPT AT KALB AND KPSF WHERE GUSTS AS HIGH AS 35 KNOTS WILL BE
POSSIBLE.
TONIGHT INTO THURSDAY...THE LOSS OF DAYTIME HEATING WILL HELP WINDS
SUBSIDE THIS EVENING ALONG WITH GRADUALLY CLEARING SKIES AS WEAK
HIGH PRESSURE BUILDS ACROSS THE REGION. MID CLOUDS WILL GRADUALLY
BUILD FROM WEST TO EAST ACROSS THE REGION AHEAD OF ANOTHER
APPROACHING CLIPPER SYSTEM WITH VCSH DEVELOPING BY THE END OF THE
TAF PERIOD...ESPECIALLY NORTH AND WEST.
WINDS WILL BE LIGHT AND VARIABLE TONIGHT GENERALLY LESS THAN 8 KNOTS
BEFORE INCREASING AFTER DAYBREAK THURSDAY OUT OF THE SOUTHWEST AT
10-15 KNOTS WITH GUSTS 20-25 KNOTS.
OUTLOOK...
THURSDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY SLIGHT CHANCE OF SHSN.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SUNDAY-MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN...SN.
&&
.HYDROLOGY...
NO HYDRO IMPACTS ARE EXPECTED ON THE MAIN STEM RIVERS THE NEXT 5
DAYS. AN ARCTIC AIR MASS WILL REMAIN ACROSS THE HYDRO SERVICE AREA
FOR THE ENTIRE WEEK WHICH WILL ALLOW ICE TO REFORM...THICKEN...AND
STRENGTHEN ON AREA RIVERS AND LAKES THROUGH THE WEEK.
LIGHT PRECIPITATION IS EXPECTED DURING THE WEEK...AND ANY THAT
DOES OCCUR WILL BE IN THE FORM OF SNOW SHOWERS OR LIGHT SNOW FROM
CLIPPER LOWS OR LAKE EFFECT.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
NYZ032-038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...11/WASULA
NEAR TERM...11/NAS/WASULA
SHORT TERM...11
LONG TERM...KL
AVIATION...IRL
HYDROLOGY...11/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1233 PM EST WED FEB 26 2014
.SYNOPSIS...
A CLIPPER LOW CONTINUES TO MOVE ACROSS SOUTHERN QUEBEC THIS
AFTERNOON...AS ITS COLD FRONT MOVES THROUGH NEW ENGLAND WITH A
REINFORCING SHOT OF ARCTIC AIR BEHIND IT. ANOTHER CLIPPER WILL BRING
A CHANCE OF MORE SNOW SHOWERS AND SNOW SQUALLS ON THURSDAY WITH SOME
BITTERLY COLD AIR FOR EASTERN NEW YORK AND WESTERN NEW ENGLAND
THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1233 PM EST...CLIPPER TYPE LOW CONTINUES TO MOVE ACROSS SRN
QUEBEC TOWARDS NRN ME AND NEW BRUNSWICK. THE COLD FRONT HAS MOVED
THROUGH WITH DIFFUSE SNOW SHOWERS AND FLURRIES...ASIDE FROM A LAKE
EFFECT SNOWBAND COMING OFF LAKE ONTARIO INTO THE TUG HILL PLATUEAU
INTO THE WRN DACKS AND MOST SPECIFICALLY NRN HERKIMER CO. THE
INLAND EXTENT HAS BEEN DIFFICULT DOWNSTREAM. THE LAKE EFFECT SNOW
ADVISORY REMAINS IN EFFECT FOR HERKIMER CO...BUT WE MAY DROP SRN
HERKIMER WITH THE NEXT UPDATE...AS THE 260-270 DEG TRAJECTORY
FAVORS NRN HERKIMER. THE LATEST HRRR GUIDANCE SHOWS THE BAND
WEAKENING BY THIS EVENING AND LIFTING NORTHWARD. WE ALSO LOWERED
AMOUNTS TO 3 TO 6 INCHES FOR THE AREA. MOST OF THE SCT SNOW
SHOWERS PRODUCED LESS THAN AN INCH OF SNOW. PLEASE SEE OUR LATEST
PNS...WITH ISOLD HIGHER AMOUNTS. TEMPS LOOKS ON TRACK WITH BRISK
CONDITIONS AND HIGHS A SOLID 10 TO 15 DEGREES BELOW NORMAL.
H850 TEMPS CRASH AGAIN TO -19C TO -22C OVER THE FCST AREA BY THE
LATE PM. IT WILL ALSO BECOME WINDY IN THE WAKE OF THE FRONT WITH
UPSLOPE SNOW SHOWERS POSSIBLE OVER THE TACONICS...BERKSHIRES...AND
SRN GREENS. IN ADDITION TO LAKE EFFECT SNOWS THERE IS THE
SLIGHT POSSIBILITY OF A WINDEX TYPE EVENT IN THE WAKE OF THE
ARCTIC FRONT AS RH VALUES IN THE LOWER LEVELS ARE GREATER THAN 70
PERCENT AND T1-T5 LAYER TEMPS DIFFER BY MORE THAN 10 C. IT WILL BE
VERY CHILLY TODAY WITH HIGHS ONLY RANGING FROM THE LOW TO MID
TEENS NORTHWEST TO THE LOW TO MID 20S SOUTHEAST.
TONIGHT....BLUSTERY CONDITIONS WILL PERSIST THROUGH THE EVENING
HOURS AND THE LAKE EFFECT BAND WILL COME TO AN END AS A WEAK RIDGE
OF HIGH PRESSURE BUILDS IN FROM THE SOUTH AHEAD OF THE NEXT
CLIPPER TYPE SYSTEM WHICH WILL ALREADY BE MOVING INTO THE SE
ONTARIO AND THE ERN GREAT LAKES REGION BY LATE TONIGHT. WIND CHILL
VALUES WILL BE CLOSE TO ADVISORY CRITERIA AND MAINLY ACROSS THE
WESTERN ADIRONDACKS. OVERNIGHT LOWS ARE EXPECTED TO RANGE FROM 10
BELOW TO 5 ABOVE ZERO.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
THU-THU NIGHT....THE SECOND CLIPPER TYPE SYSTEM IMPACTS THE FA AS
IT MOVES ACROSS SOUTHERN QUEBEC...NRN NY AND NRN NEW ENGLAND
SWINGING ANOTHER ARCTIC COLD FRONT THROUGH OUR REGION. THIS
SYSTEM IS EVEN STRONGER THAN THE FIRST CLIPPER TYPE SYSTEM AND
LOOKS TO SET UP A CLASSIC WINDEX EVENT IN THE WAKE OF THE COLD
FRONT WHICH WILL BE ENHANCED BY A SECONDARY TROUGH OF LOW PRESSURE.
THE BEST MOISTURE CONVERGENCE LOOKS LIKE IT WILL BE OVER THE WRN
DACKS AGAIN...WHERE A FEW INCHES OF SNOW LOOK LIKELY. MOST OTHER
LOCATIONS WILL RECEIVE A DUSTING TO AN TWO INCHES. THE WIND FIELDS
STRENGTHEN IN THE WAKE OF THE CLIPPER WITH SW WINDS SHIFTING TO
THE WEST WITH THE FRONTAL PASSAGE IN THE AFTERNOON. WEST WINDS OF
15 TO 25 MPH WITH SOME GUSTS TO 35 TO 40 MPH WILL BE POSSIBLE DUE
TO FUNNELING DOWN THE MOHAWK VALLEY INTO THE CAPITAL REGION INTO
THE CNTRL TACONICS...AND BERKSHIRES. THESE GUSTY WINDS ARE ALSO
EXPECTED IN THE ERN AND NRN CATSKILLS. HIGHS ON THURSDAY WILL
GENERALLY BE IN THE UPPER TEENS TO UPPER 20S. LOWS THURSDAY NIGHT
WILL BE IN THE 10 BELOW ZERO TO 5 ABOVE ZERO RANGE WITH WIND CHILL
VALUES REACHING ADVISORY CRITERIA ACROSS SOME OF THE HIGHER
TERRAIN.
FRIDAY AND FRIDAY NIGHT HIGH PRESSURE WILL PROVIDE PLENTY OF
SUNSHINE TO THE REGION ALTHOUGH IT WILL STILL BE VERY COLD AND
BLUSTERY. EXPECT HIGH ON FRIDAY TO BE IN THE TEENS TO AROUND 20
WITH PERHAPS ONLY SINGLE DIGITS ACROSS PORTIONS OF THE WESTERN
ADIRONDACKS. LOWS FRIDAY NIGHT WILL BE IN THE 10 BELOW TO 5 ABOVE
ZERO RANGE ONCE AGAIN.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
BELOW TO MUCH BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE
LONG TERM PORTION OF THE FORECAST. IN ADDITION...THE POTENTIAL FOR
STORMINESS WILL INCREASE...ESP BY SUN NT-MON...AS SHORTWAVE ENERGY
ORIGINATING OVER THE SOUTHWEST U.S. EJECTS RAPIDLY
NORTHEASTWARD...AHEAD OF A LONG WAVE TROUGH PIVOTING SLOWLY E/SE
ACROSS THE NORTHERN PLAINS.
OVERALL...MODELS HAVE TRENDED SLIGHTLY SOUTHWARD WITH REGARD TO
THEIR RESPECTIVE SURFACE FEATURES COMPARED TO 24 HOURS AGO /00Z 25
RUNS/.
TAKING A LOOK AT SOME PV TRACES...IT APPEARS THAT ENERGY CURRENTLY
DIGGING SOUTHWARD WELL SOUTHWEST OF THE ALEUTIAN ISLANDS WILL BE THE
MAIN DRIVER FOR EARLY NEXT WEEK...AS THIS PV ANOMALY POSSIBLY
REACHES SOUTHERN CA EARLY THIS WEEKEND...AS THE UPPER LEVEL
TROUGH/LOW CURRENTLY FURTHER EAST SPLITS INTO TWO PIECES...ONE
TRANSLATING NORTHWARD WELL OFF THE PACIFIC NW COAST...AND ANOTHER
PIECE TRANSLATES EAST AND WEAKENS...AFFECTING OUR REGION ON
SATURDAY. THE MODELS SEEM TO HANDLE THE DIGGING ENERGY
DIFFERENTLY...WITH THE 00Z/26 ECMWF A BIT FASTER IN PROGRESSING THIS
ENERGY OUT ACROSS THE SOUTHERN PLAINS AND EVENTUALLY OHIO VALLEY FOR
SUN-MON...AND ALSO KEEPING THE ENERGY IN TACT A BIT LONGER...WHILE
THE 00Z/26 GFS IS SLOWER...AND SEEMS TO WEAKEN/SHEAR THIS ENERGY
FASTER WITH A SOMEWHAT FLATTER WAVE FOR AFFECTING THE REGION FOR
LATE MON INTO TUE. HAVE SIDED CLOSER TO THE 00Z/26 WPC/ECMWF
SOLUTIONS.
EITHER WAY...IT APPEARS THAT WARM ADVECTION WELL AHEAD OF ANY SUCH
WAVE SHOULD ALLOW CLOUDS AND PRECIP TO DEVELOP SUN NT...AND INTO
MONDAY...BEFORE POSSIBLY TAPERING OFF LATE MON NT OR TUES. BASED ON
CURRENT 00Z/26 DETERMINISTIC AND ENSEMBLE GUIDANCE...SOUTHERN
PORTIONS OF THE FORECAST AREA APPEAR TO BE MOST FAVORED FOR MODERATE
OR GREATER AMOUNTS OF PRECIPITATION...BUT AGAIN...THIS SOUTHWARD
MODEL TREND STARTED WITHIN THE LAST 24 HOURS...AND WOULD NOT BE
SURPRISED TO ULTIMATELY SEE MODELS SOLUTIONS TREND BACK SLIGHTLY
NORTHWARD AGAIN OVER THE NEXT 1-3 DAYS WITH REGARD TO THIS POTENTIAL
STORM SYSTEM.
HERE ARE SOME MORE SPECIFICS...
SAT-SUN...THE FIRST WAVE IS EXPECTED TO WEAKEN...AND TRANSLATE
RAPIDLY EAST/NORTHEAST ON SAT. A SURGE OF WEAK WARM ADVECTION SHOULD
ALLOW FOR ABUNDANT CLOUDS AND SOME LIGHT SNOW/SNOW SHOWERS TO
OVERSPREAD THE REGION LATE SAT MORNING INTO THE
AFTERNOON...ESPECIALLY FOR AREAS NEAR AND WEST OF THE HUDSON RIVER.
THE SNOW SHOWERS ARE EXPECTED TO SINK SOUTHWARD SAT NT AND EARLY
SUNDAY...AS THE ASSOCIATED ARCTIC FRONTAL BOUNDARY ALSO DROPS SOUTH.
WILL THEREFORE INDICATE CHC POPS FOR MOST AREAS FROM ALBANY N AND
W...AND MAINLY SLIGHT CHC TO THE S/E THROUGH SAT...THEN CHC POPS ALL
AREAS FOR SAT NT INTO EARLY SUN...WITH SOME LIKELY POPS FOR NW
AREAS.
THERE IS A POSSIBILITY THAT SNOW SHOWERS AND/OR AREAS OF LIGHT SNOW
ACTUALLY TAPER OFF ACROSS NORTHERN AREAS SUNDAY
AFTERNOON/EVENING...AS THE FRONT AND ASSOCIATED MID LEVEL FORCING
SHIFTS FURTHER SOUTH. WILL THEREFORE TAPER POPS IN THE AFTERNOON FOR
NORTHERN AREAS INTO THE SLIGHT CHC RANGE...WITH CHC POPS REMAINING
FOR CENTRAL AND SOUTHERN AREAS.
SUN NT-MON...THE AFOREMENTIONED SECOND WAVE SHOULD EJECT OUT OF THE
SOUTHWEST U.S...AND WILL CONTINUE TRANSLATING E/NE...ALLOWING A
LARGE AREA OF ISENTROPIC LIFT TO DEVELOP ACROSS THE REGION. THIS
SHOULD ALLOW FOR SNOW TO OVERSPREAD THE REGION SUN NT...AND CONTINUE
THROUGH MONDAY. SNOW SHOULD BE THE MAIN P-TYPE FOR MOST AREAS. BASED
ON THE SLIGHT SOUTHWARD TREND OF THE 00Z/26 MODELS WITH REGARD TO
STRONGEST MID LEVEL FORCING AND MOISTURE...HAVE ADDED LIKELY POPS
ACROSS SOUTHERN AND EASTERN PORTIONS OF THE FORECAST AREA...WITH CHC
POPS ELSEWHERE.
TEMPS WILL REMAIN BELOW TO MUCH BELOW NORMAL THROUGH THE PERIOD. THE
MILDEST DAY SHOULD BE SATURDAY...AHEAD OF THE INCOMING ARCTIC
FRONTAL BOUNDARY...WITH MAX TEMPS REACHING THE LOWER 30S IN VALLEY
AREAS...AND 20S ACROSS MOST HIGHER ELEVATIONS. FOR SAT NT/SUN
AM...AS THE ARCTIC BOUNDARY SINKS SOUTHWARD...TEMPS SHOULD FALL INTO
THE TEENS IN MOST AREAS...EXCEPT FOR SINGLE DIGITS ACROSS PORTIONS
OF THE ADIRONDACKS. ON SUNDAY...MAX TEMPS SHOULD GENERALLY ONLY
REACH THE 20S IN VALLEYS WITH TEENS ACROSS THE ADIRONDACKS. TEMPS
SHOULD THEN FALL INTO THE SINGLE DIGITS TO MID TEENS SUN NT...AND
THEN ONLY RISE INTO THE TEENS AND 20S FOR MONDAY...ALTHOUGH THERE IS
THE POTENTIAL FOR EVEN COLDER MAX TEMPS IF ENOUGH LOW LEVEL ARCTIC
AIR SEEPS SOUTHWARD INTO THE REGION IN THE WAKE OF THE WEEKEND
WAVE...AND IF SNOW FALLS INTO THIS COLD AND RELATIVELY DRY LOW LEVEL
AIR. EXPECT SINGLE DIGITS AND TEENS AGAIN FOR MON NT/TUE AM...WITH
TUE MAXES MAINLY IN THE 20S IN VALLEYS...AND TEENS ACROSS HIGHER
ELEVATIONS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
WEAK LOW PRESSURE WILL TRACK ACROSS SOUTHEAST CANADA TODAY. A COLD
FRONT TRAILING FROM THIS LOW WILL PASS THROUGH THE TAF SITES DURING
THE MID TO LATE MORNING HOURS...PRECEDED AND ACCOMPANIED BY SNOW
SHOWERS. SOME LAKE EFFECT SNOWBANDS COULD CONTINUE INTO EARLY THIS
AFTERNOON...BEFORE HIGH PRESSURE BRINGS A PERIOD OF MAINLY CLEAR
SKIES AND DIMINISHING WINDS TO THE TAF SITES FOR TONIGHT.
THE AFOREMENTIONED COLD FRONT WILL APPROACH FROM THE WEST...AND PASS
THROUGH THE TAF SITES BETWEEN ROUGHLY 14Z-17Z/WED. A BAND...OR
PERHAPS MULTIPLE THIN BANDS OF SNOW SHOWERS SHOULD ACCOMPANY AND
PRECEDE THIS FRONT. FOR NOW...HAVE INDICATED VCSH DURING THIS TIME
PERIOD FOR MOST TAF SITES. HOWEVER...SHOULD ANY SNOW SHOWERS PASS
THROUGH...BRIEF VSBY REDUCTIONS INTO MVFR/IFR WILL BE POSSIBLE.
BEHIND THE FRONT...MAINLY VFR CONDITIONS ARE EXPECTED FOR THE
AFTERNOON/EARLY EVENING. HOWEVER...WILL HAVE TO WATCH FOR ANY
RESIDUAL LAKE ENHANCED/EFFECT SNOW SHOWERS OR SNOW BANDS...WHICH
COULD IMPACT KGFL/KALB/KPSF INTO LATE AFTERNOON...AGAIN POSSIBLY
PRODUCING BRIEF VSBY REDUCTIONS INTO MVFR/IFR. VFR CONDITIONS ARE
EXPECTED FROM SUNSET...THROUGH 12Z/THU.
WINDS WILL INCREASE FROM THE SOUTHWEST TO WEST AHEAD OF THE FRONT TO
8-12 KT BY MID MORNING...THEN SHIFT INTO THE WEST TO NORTHWEST
BEHIND THE FRONT AND INCREASE TO 10-16 KT...WITH SOME GUSTS OF 25-30
KT POSSIBLE...ESP AT KALB AND KPSF WHERE WINDS COULD BE FURTHER
ENHANCED DUE TO THE FUNNELING EFFECTS DOWN THE MOHAWK VALLEY. WINDS
WILL GRADUALLY DECREASE FROM THE WEST/NORTHWEST TO 5-10 KT BY LATE
EVENING...AND THEN BECOMING LIGHT/VARIABLE AFTER MIDNIGHT.
OUTLOOK...
THURSDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY SLIGHT CHANCE OF SHSN.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN...SN.
&&
.HYDROLOGY...
NO HYDRO IMPACTS ARE EXPECTED ON THE MAIN STEM RIVERS THE NEXT 5
DAYS. AN ARCTIC AIR MASS WILL REMAIN ACROSS THE HYDRO SERVICE AREA
FOR THE ENTIRE WEEK WHICH WILL ALLOW ICE TO REFORM...THICKEN...AND
STRENGTHEN ON AREA RIVERS AND LAKES THROUGH THE WEEK.
LIGHT PRECIPITATION IS EXPECTED DURING THE WEEK...AND ANY THAT
DOES OCCUR WILL BE IN THE FORM OF SNOW SHOWERS OR LIGHT SNOW FROM
CLIPPER LOWS OR LAKE EFFECT.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...LAKE EFFECT SNOW ADVISORY UNTIL 10 PM EST THIS EVENING FOR
NYZ032-038.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...11/WASULA
NEAR TERM...11/NAS/WASULA
SHORT TERM...11
LONG TERM...KL
AVIATION...KL
HYDROLOGY...11/WASULA
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
300 PM CST WED FEB 26 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 220 PM CST WED FEB 26 2014
MAIN FORECAST CONCERN IN THE SHORT TERM IS STRONG WINDS AND THE
RESULTING BLOWING/DRIFTING SNOW EXPECTED ACROSS THE AREA THROUGH
THIS EVENING. LATEST SURFACE ANALYSIS AND OBS SHOW THE COLD FRONT
MOVING THROUGH THE NORTH HALF OF THE FORECAST AREA AT THE CURRENT
TIME... WITH A NICE WIND SHIFT FROM SOUTHWEST TO NORTHWEST BEHIND
THE FRONT. WE/RE SEEING STRONG SOUTHWEST WINDS... SUSTAINED NEAR
20KT WITH GUSTS TO AROUND 30KT AHEAD OF THE FRONT... AND NORTHWEST
WINDS OF AROUND 25KT WITH GUSTS OF 35KT IMMEDIATELY BEHIND THE
FRONT. HOWEVER... FORECAST SOUNDINGS FROM THE RAP AND NAM CONTINUE
TO SUGGEST THE BEST MIXING WITH POST FRONTAL COLD ADVECTION AND
SUBSIDENCE WILL OCCUR DURING THE EARLY EVENING ACROSS MOST OF THE
AREA... WITH 00-05Z LOOKING LIKE PRIME TIME FOR STRONG WINDS AND
POTENTIAL BLIZZARD CONDITIONS. THE HOPWRF MATCHES UP WITH THIS
TIMING QUITE WELL... AND HAS ENSEMBLE MEAN SUSTAINED WINDS OF AROUND
30 MPH AND GUSTS WELL IN EXCESS OF 40 MPH FOR A PERIOD OF SEVERAL
HOURS. LOCATIONS WHICH WILL SEE THE GREATEST IMPACT STILL LOOK TO BE
THE OPEN AREAS OVER THE WESTERN AND SOUTHERN PART OF THE AREA...
WHERE THE COMBINATION OF DEEP SNOW... STRONG WINDS... AND FAVORABLE
TERRAIN SHOULD LEAD TO WIDESPREAD LOW VISIBILITY AND SIGNIFICANT
DRIFTING SNOW. SOME LIGHT SNOW AND FLURRIES WILL SLIP THROUGH THE
NORTH/NORTHEAST PORTION OF THE AREA THROUGH THIS EVENING... BUT ANY
ACCUMULATION WILL BE VERY MINOR GIVEN THE EXTREMELY LIMITED MOISTURE
AHEAD OF THE SHORTWAVE AND COLD FRONT. THE PRESSURE GRADIENT LOOKS
TO QUICKLY RELAX OVERNIGHT INTO THURSDAY MORNING... SO WE SHOULD SEE
THE BLOWING/DRIFTING SETTLE DOWN FAIRLY QUICKLY AFTER MIDNIGHT. WILL
KEEP THE GOING HEADLINES IN PLACE... AS WELL AS THE TIMING... WHICH
STILL LOOKS TO ENCAPSULATE THE ENTIRETY OF THE EVENT. HOWEVER...
WIND CHILLS WILL BE PLUMMETING OVERNIGHT AS COLDER AIR ARRIVES.
ALTHOUGH WINDS WILL BE DYING OFF... THEY WILL STILL BE SUFFICIENT TO
PRODUCE VERY COLD WIND CHILLS... WHICH WILL PERSIST INTO THE DAY ON
THURSDAY. THE NORTHERN COUNTIES LOOK LIKE THEY WILL SEE WIDESPREAD
WIND CHILLS OF -35 TO -45... WHILE THE CENTRAL AND SOUTHERN PORTION
OF THE AREA WILL MAINLY BE IN THE -25 TO -35 RANGE. SO... ALTHOUGH
THE HEADLINES FOR BLOWING/DRIFTING SNOW WILL END OVERNIGHT... THEY
WILL BE REPLACED BY WIND CHILL HEADLINES THROUGH THURSDAY MORNING.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 220 PM CST WED FEB 26 2014
LONGER TERM TRENDS CONTINUE TO REMAIN COLD. TEMPERATURES ARE
EXPECTED TO REMAIN FAR BELOW NORMAL THROUGH THE ENTIRE PERIOD.
STANDARDIZED ANOMALIES FROM THE NAM AND GEFS CONTINUE TO SHOW H85
TEMPERATURES AROUND 2 TO 3 STANDARD DEVIATIONS BELOW
NORMAL...WHICH SHOULD CONTINUE TO YIELD 30 TO 40 DEGREES BELOW
NORMAL THROUGH MOST OF THE PERIOD. SOME INDICATIONS AT THE END OF
THE PERIOD...INTO NEXT WEEK...THE UPPER FLOW PATTERN MAY FLATTEN A
BIT OVER THE NORTHERN CONUS...ALLOWING SOME MODIFIED PACIFIC TYPE
AIR TO INTRUDE ACROSS THE NORTHERN PLAINS. THAT IS PRETTY FAR IN
THE FUTURE AND THE 12Z ECMWF IS THE MODEL MOST PROMINENT WITH THIS
OVERALL DEVELOPMENT.
A COUPLE OF SNOW CHANCES COME INTO PLAY...NAMELY FRIDAY AND
SATURDAY/SATURDAY NIGHT. MODELS TREND AN INVERTED TROUGH EAST
ACROSS THE CWA ON FRIDAY. BEST FORCING IS FOUND OVER THE SOUTHERN
CWA. WILL CONTINUE TO MENTION LIKELY POPS FOR THE SOUTHERN
THIRD OF THE AREA THEN. WILL HAVE TO MONITOR FOR DEVELOPMENT ON
THE NORTH END OF THE TROUGH AS WELL...BUT CONTINUE CHANCE POPS
THERE. THIS WOULD GENERATE AN INCH OR TWO OF ACCUMULATION TO THE
SOUTH BY FRIDAY EVENING. SHOULD BE A FLUFFY SNOW AND WINDS DO
INCREASE SOME IN THE WAKE OF THE TROUGH. AT THE PRESENT TIME THEY
DO NOT APPEAR TO BE STRONG ENOUGH TO GENERATE SIGNIFICANT
BLOWING/DRIFTING SNOW CONCERNS.
THE NEXT SNOW THREAT ARRIVES FOR SATURDAY AND SATURDAY NIGHT.
MODELS IN SOME DISAGREEMENT AS TO HOW FAR AND SNOW THREAT WOULD
BE AS LARGE COLD ARCTIC HIGH BUILDS SOUTHEAST OVER THE AREA INTO HE
WEEKEND. AT THE MOMENT THE BEST AGREEMENT REMAINS OVER FAR SOUTHERN
MINNESOTA FOR MEASURABLE SNOW AND WILL MENTION LIKELY POPS IN THAT
AREA.
WIND CHILL CONCERNS WILL CONTINUE INTO THE WEEKEND BUT WINDS
SHOULD GRADUALLY DIMINISH AS THE ARCTIC HIGH SETTLES CLOSE TO THE
CWA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1118 AM CST WED FEB 26 2014
MAIN ISSUE OF CONCERN WILL BE STRONG WINDS AHEAD OF COLD FRONT
THROUGH MID AFTERNOON... THEN BEHIND THE FRONT WITH THE STRONG
COLD ADVECTION THROUGH THIS EVENING. BLOWING SNOW IS EXPECTED
GIVEN THE EXPECTATION FOR WIND GUSTS AOA 35KT... BUT WE/RE STILL
WAITING TO SEE HOW BAD THE BLOWING GETS SINCE MOST OF THE MORE
RECENT SNOWFALL IS STILL DOWNSTREAM OF WHERE CURRENT HIGHER WINDS
ARE OCCURRING. THERE ARE SOME SPOTTY MVFR CEILINGS NEAR THE
FRONTAL BOUNDARY... BUT THOSE AND THE MAIN CHANCE FOR ANY LIGHT
SNOW STILL LOOKS TO MAINLY IMPACT LOCATIONS NORTH/EAST OF THE
FORECAST AREA. HOWEVER... CONTINUED TO MENTION AT LEAST SOME
POSSIBILITY OF NEAR-MVFR CEILINGS FOR A BRIEF WINDOW OF TIME
ACROSS THE NORTHEAST TAF SITES. OTHERWISE... STUCK VERY CLOSE TO
THE PREVIOUS FORECAST... WHICH LOOKED TO HAVE A GOOD HANDLE ON THE
TIMING OF THE STRONGEST WINDS AND A BEST GUESS OF WHAT
VISIBILITIES WILL DO WITH THE BLOWING SNOW. SHOULD SEE THINGS
QUICKLY IMPROVE OVERNIGHT... WITH LIGHT WINDS BY MORNING.
KMSP...MAIN AREA OF UNCERTAINTY WITH THE TAF IS THE DEGREE OF
VISIBILITY REDUCTION WHEN WINDS PICK UP LATER THIS AFTERNOON INTO
THIS EVENING. STAYED SOMEWHAT OPTIMISTIC FOR NOW... BUT AMENDMENTS
COULD CERTAINLY OCCUR IF WE START TO SEE VISIBILITIES
SIGNIFICANTLY DROP IN UPSTREAM LOCATIONS. OTHERWISE... HAVE GOOD
CONFIDENCE OVERALL IN THE TIMING OF WIND SHIFT/SPEEDS AND THE
POTENTIAL WINDOW OF ANY NEAR-MVFR CEILINGS.
/OUTLOOK FOR KMSP/
THURSDAY NIGHT...VFR. SOUTHEAST WIND 5 TO 15 KT.
FRIDAY...MVFR CEILINGS AND VISIBILITIES POSSIBLE WITH A CHANCE OF
SNOW. SOUTHEAST WIND 5 TO 10 KT SHIFTING NORTHWEST.
FRIDAY NIGHT...MVFR CEILINGS POSSIBLE. NORTHWEST WIND 5 TO 10 KT.
SATURDAY AND SATURDAY NIGHT...VFR. NORTHWEST WIND 5 TO 15 KT
DECREASING TO LESS THAN 5 KT.
SUNDAY...VFR. NORTHWEST WIND 5 TO 15 KT.
SUNDAY NIGHT...MVFR CEILINGS POSSIBLE. NORTHWEST WIND 10 TO 15
KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND CHILL ADVISORY FROM 3 AM TO NOON CST THURSDAY FOR MNZ047-
048-054>070-073>078-082>085-091>093.
BLIZZARD WARNING UNTIL 3 AM CST THURSDAY FOR MNZ066>069-074>077-
082>085-091>093.
WIND CHILL WARNING FROM 3 AM TO NOON CST THURSDAY FOR MNZ041>045-
049>053.
BLIZZARD WARNING UNTIL 3 AM CST THURSDAY FOR MNZ041-042-048-049-
055>059-065-073.
WINTER WEATHER ADVISORY UNTIL 3 AM CST THURSDAY FOR MNZ043>045-
047-050-051-054-064.
WINTER WEATHER ADVISORY UNTIL 3 AM CST THURSDAY FOR MNZ052-053-
060>063-070-078.
WI...WIND CHILL ADVISORY FROM 3 AM TO NOON CST THURSDAY FOR
WIZ023>028.
WIND CHILL WARNING FROM 3 AM TO NOON CST THURSDAY FOR WIZ014>016.
WINTER WEATHER ADVISORY UNTIL 3 AM CST THURSDAY FOR WIZ014>016-
023>028.
&&
$$
SHORT TERM...TRH
LONG TERM...DWE
AVIATION...TRH
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
243 PM EST WED FEB 26 2014
.SYNOPSIS...
A PROLONGED STRETCH OF COLD WEATHER...WITH TEMPERATURES RUNNING
10 TO 20 DEGREES BELOW AVERAGE...IS EXPECTED TO PERSIST THROUGH
EARLY NEXT WEEK. REINFORCING ARCTIC FRONTS MOVING FROM WEST TO
EAST ACROSS THE NORTH COUNTRY THIS MORNING AND AGAIN DURING THE
MIDDAY THROUGH AFTERNOON HOURS THURSDAY WILL BRING SCATTERED SNOW
SHOWERS AND SNOW SQUALLS. A QUICK DUSTING TO A COUPLE INCHES OF
SNOW IS POSSIBLE WITH THESE FRONTAL PASSAGES...ALONG WITH BRIEF
PERIODS OF VERY LOW VISIBILITY. HIGH TEMPERATURES TODAY WILL
RANGE FROM THE MID TEENS TO LOWER 20S...AND DEVELOPING WESTERLY
WINDS OF 15 TO 25 MPH WILL RESULT IN WIND CHILL VALUES NEAR ZERO.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1222 PM EST WEDNESDAY...SNOW SQUALL ACTIVITY HAS MOSTLY
ENDED ACROSS EASTERN VERMONT AND HAVE ADJUSTED POPS/WX GRIDS
ACCORDINGLY. CLOUDS ARE VARIABLE ACROSS THE AREA WITH SOME BREAKS
HERE AND THERE...ESPECIALLY IN THE CHAMPLAIN VALLEY. HAVE
ADJUSTED SKY GRIDS TO ACCOUNT FOR THIS AS WELL. BRISK WESTERLY
WINDS CONTINUE WITH COLDER THAN NORMAL MAX TEMPS. PREVIOUS
DISCUSSIONS FOLLOW.
SNOW SQUALL ACTIVITY CURRENTLY MOVING ACROSS THE NORTHERN
CHAMPLAIN VALLEY. THINK THAT CURRENT FORECAST IS IN GOOD SHAPE SO
DID NOT ALTER POPS OR WX AT ALL. THIS AREA OF SQUALLS WILL PUSH
EASTWARD ACROSS VERMONT OVER THE NEXT FEW HOURS AND THEN POPS
DECREASE LATE THIS AFTERNOON AND EVENING. PREVIOUS DISCUSSION
FOLLOWS.
SNOW SHOWER ACTIVITY HAS LOST ORGANIZATION AND STRUCTURE 10-12Z
AS IT MOVED AWAY FROM THE LAKE INDUCED INSTABILITY NEAR LAKE
ONTARIO AND AS FRONTOGENESIS CIRCULATION HAS BEEN DISRUPTED BY
THE STEEP TERRAIN OF THE ADIRONDACKS. EXPECTATION - CONSISTENT
WITH 11Z RAP - IS THAT LIGHT SNOW SHOWERS WILL SHIFT THRU THE
CHAMPLAIN VALLEY NEXT 1-3 HOURS...AND THEN SHOW AN INCREASE IN
INTENSITY ACROSS CENTRAL AND ERN VT AFTER 15Z WITH DEVELOPMENT OF
STEEP LOW- LEVEL LAPSE RATES AND SBCAPE UP TO 100 J/KG. BEST
CHANCE FOR BRIEF MODERATE TO HEAVY SNOW WILL BE ACROSS THE CT
RIVER VALLEY BEFORE ACTIVITY SHIFTS EAST INTO NH. WE/LL SEE A
QUICK DUSTING TO 2" IN SPOTS...HIGHEST CENTRAL/ERN VT DURING THE
MIDDAY HRS. OTHERWISE...LOOKING AT CONTINUED COLD TEMPS WITH
HIGHS IN THE MID TO UPPER TEENS...EXCEPT LOW 20S IN FAR SERN
SECTIONS. INCREASED COLD ADVECTION THIS AFTN MAY ALLOW TEMPS TO
LEVEL OFF AFTER NOON EDT. STEEP LOW-LEVEL LAPSE RATES WILL
CONTRIBUTE TO GUSTY S-SW WINDS IN ADVANCE OF THE FRONT 15-25 MPH
WITH POST- FRONTAL GUSTS TO 30 MPH...SHIFTING INTO THE WEST
FOLLOWING FRONTAL PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY NIGHT/...
AS OF 342 AM EST WEDNESDAY...SFC RIDGE BUILDS BRIEFLY ACROSS THE
AREA THIS EVENING AND OVERNIGHT...ALLOWING FOR DIMINISHING WIND
AND A PERIOD OF PARTIAL CLEARING. WITH ARCTIC AIR MASS IN PLACE
(850MB TEMPS -24C)...THE RADIATIONAL COOLING WILL RESULT IN COLD
OVERNIGHT LOWS RANGING FROM NEAR ZERO IN THE CHAMPLAIN VALLEY TO
AROUND 10 BELOW IN THE ADIRONDACKS AND NORTHEAST KINGDOM. TEMPS
MAY LEVEL OFF AFTER MIDNIGHT WITH SOME INCREASE IN CLOUDS IN
ADVANCE OF NEXT SYSTEM.
NEXT SHORTWAVE TROUGH ROTATING AROUND THE SRN PERIPHERY OF PARENT
UPPER LOW ANCHORED ACROSS JAMES BAY WILL TRANSLATE ACROSS THE ERN
GREAT LAKES AROUND 12Z THURSDAY...AND ACROSS THE NORTH COUNTRY
15-21Z TIME FRAME THURSDAY. THIS NEXT SHORTWAVE IS APPEARS
VIGOROUS IN WV IMAGERY AND IN NWP PROJECTIONS...SO QG ASCENT WILL
BE MODERATELY STRONG AS UPR TROUGH APPROACHES DURING THE DAY
THURSDAY. IT APPEARS SBCAPE VALUES WILL BE BETTER ACROSS MOST
SECTIONS OF THE NORTH COUNTRY WITH THIS SYSTEM TOMORROW (AS
OPPOSED TO THE WEAKER ONE TODAY)...WITH 06Z NAM INDICATING
100-150 J/KG ACROSS MUCH OF THE NORTH COUNTRY. ALSO INTERESTING
ARE PROGGED PBL HEIGHTS TO 600MB WITH STEEP LAPSE RATES FROM THE
SFC-12 KFT...A DEFAULT TROPOPAUSE IN THE ARCTIC AIR REGIME.
SO...GOOD CONVECTIVE SNOW POTENTIAL. FRONTOGENETIC FORCING IS NOT
AS WELL ORGANIZED AS WEDNESDAY...SO WOULD ANTICIPATE SMALLER LINE
SEGMENTS AND CONVECTIVE CELLS PRODUCING BRIEF BURSTS OF HEAVIER
SNOW SHOWERS AND POSSIBLE SQUALLS WITH GUSTS 30-35 MPH. A QUICK
1-3" IS POSSIBLE IN SPOTS...AND WILL AGAIN CAUSE SOME BRIEF
TRANSPORTATION HAZARD DUE TO LOW VSBY AND SNOW COVERED ROADS.
MADE MENTION OF THIS AS WELL IN THE MORNING HWO. HIGHS THURSDAY
IN THE UPR TEENS TO LOW 20S. SYSTEM MOVES EAST OF THE AREA
THURSDAY NIGHT WITH JUST A FEW LINGERING MTN FLURRIES. LOWS AGAIN
ZERO TO -10F...BUT LOCALLY COLDER IN THE NRN ADIRONDACKS IF
PARTIAL CLEARING CAN OCCUR LATE.
FRIDAY LOOKS QUIET WITH LOW TO MID LEVEL RIDGING BUILDING INTO
THE REGION FROM THE WEST. SHOULD BE PARTLY TO MOSTLY SUNNY AND
KEPT THE FORECAST DRY. REINFORCED CAA BEHIND THURSDAY/S TROUGH
KEEPS 850MB TEMPS OF -23 TO -24C ACROSS THE REGION FOR FRIDAY.
RATHER INEFFECTIVE SUNSHINE WITH HIGHS IN THE LOW-MID TEENS...AND
LOCALLY 8-9F IN THE NRN ADIRONDACK REGION.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 243 PM EST WEDNESDAY...GOING INTO THE UPCOMING WEEKEND...HIGH
PRESSURE OFF THE NEW ENGLAND COAST WITH SOUTHERLY FETCH STARTS
OFF THE SATURDAY TIMEFRAME. LATEST GFS/ECMWF BOTH BRING LOW
PRESSURE EASTWARD THRU NORTHERN PORTIONS OF THE GREAT LKS AND
SLOWLY INTO SOUTHERN QUEBEC BY SATURDAY NIGHT. WITH APPROACH OF
THIS SYSTEM...SFC RIDGE DOES SLIDE SOUTH OF THE AREA AND IN EFFECT
SLOWS APPROACH OF TRAILING FRONTAL BOUNDARY UNTIL LATE SAT NGT.
BULK OF PRECIP W/ FROPA TO OCCUR ON SUNDAY...WITH NOSING SFC RIDGE
BEHIND FRONT COMBINED WITH ZONAL MID-LEVEL FLOW PUSHING FRONT
OFFSHORE FOR SUNDAY NIGHT. RESPITE FROM PRECIP IS BRIEF THOUGH AS
SECONDARY LOW ALONG FRONT LIFTS TOWARDS THE AREA. GFS/ECMWF
SOLUTIONS DO DIFFER FROM HERE TO END OF FORECAST PERIOD... IN THAT
GFS WANTS CUTOFF UPPER LOW OVER GREAT LKS TO KEEP CHANCE FOR
PRECIP TO LINGER THRU MIDWEEK NEXT WEEK...WHILE THE ECMWF HAS
ZONAL FLOW PUSH SECOND SYSTEM OFF TO OUR SOUTH WITH SFC HIGH
PRESSURE BUILDING OVER AREA. WITH INCONSISTENCIES SHOWING WILL
KEEP PRECIP OVER AREA FOR SECOND LOW WITH HIGHEST POPS SOUTH BASED
ON TRACK...THEN SL CHANCE/CHANCE POPS FOR --SW IN REST OF TIME.
WITH THE EXCEPTION OF WAA ON SOUTHERLY FLOW INITIALLY FOR
SATURDAY...THE MAJORITY OF THE EXTEND PERIOD WILL HAVE BLW NORMAL
TEMPS FOR BOTH HIGHS AND LOWS AS A COMBO OF SFC HIGHS AND UPPER
LEVEL SUPPORT WILL KEEP REINFORCING CD AIR OVER THE REGION.
OVERALL TEMPS LOOKING FOR A RANGE OF TEENS/L20S FOR HIGHS AND ZERO
TO 10 BLW FOR OVERNGT PERIODS. AGAIN SAT/SAT NGT ARE THE OUTLIERS
FOR TEMPS DUE TO WAA SATURDAY AND THE SLOW TRANSITION BACK TO
COLDER AIRMASS DUE TO SLOW MVG FRONT SAT NGT.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...MAINLY VFR COND THRU FORECAST PERIOD W/
SCT025-040 BKN080 FOR BTV/MPV/PBG/RUT. MVFR -SW FOR RUT POSSIBLE
THRU 00Z THURS W/ 3SM VSBY. AFT 15Z THURSDAY...MVFR COND DEVELOP
WITH -SW AND CEILINGS NEAR BKN025. FOR MSS/SLK...MIX OF VFR DOWN
TO IFR COND AT TIMES W/ BLSN THRU 00Z THURSDAY DROPPING VSBY TO
3-6SM AT TIMES...THEN -SW DEVELOPING FROM LK BAND AS WINDS SHIFTS
W/ VSBY 2-5SM AND CEILINGS BKN020-040. WINDS OVERALL WSW 10-20KTS
WITH GUSTS NEAT 30KTS THRU 00Z THURS THEN 10KTS OR LESS THRU 15Z
THURSDAY THEN BECM SOUTHERLY AT 10-15KTS..
OUTLOOK 18Z THURSDAY THROUGH MONDAY... MAINLY VFR CONDITIONS BTWN
06Z AND 12Z THURSDAY...BEFORE NEXT CLIPPER SYSTEM WITH SNOW
SHOWERS AND IFR/MVFR CONDITIONS DEVELOP BTWN 15Z AND 21Z THURS. A
BRIEF SNOW SQUALL WL ONCE AGAIN BE POSSIBLE ON THURS ASSOCIATED
WITH NEXT SURGE OF ARCTIC AIR. LINGERING UPSLOPE MTN SNOW SHOWERS
WL PREVAIL AT SLK/MPV INTO EARLY FRIDAY MORNING WITH PERIODS OF
IFR/MVFR POSSIBLE...ALONG WITH GUSTY WEST/NORTHWEST WINDS. SFC
HIGH PRES WITH VFR CONDITIONS DEVELOP FRIDAY INTO
SATURDAY...BEFORE NEXT SYSTEM ARRIVES ON SAT AFTN INTO SUNDAY
WITH ADDITIONAL LIGHT SNOW SHOWERS. VFR MONDAY W/ OCNL MVFR -SW.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/NEILES
SHORT TERM...BANACOS
LONG TERM...JN
AVIATION...JN/TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1238 PM EST WED FEB 26 2014
.SYNOPSIS...
A PROLONGED STRETCH OF COLD WEATHER...WITH TEMPERATURES RUNNING
10 TO 20 DEGREES BELOW AVERAGE...IS EXPECTED TO PERSIST THROUGH
EARLY NEXT WEEK. REINFORCING ARCTIC FRONTS MOVING FROM WEST TO
EAST ACROSS THE NORTH COUNTRY THIS MORNING AND AGAIN DURING THE
MIDDAY THROUGH AFTERNOON HOURS THURSDAY WILL BRING SCATTERED SNOW
SHOWERS AND SNOW SQUALLS. A QUICK DUSTING TO A COUPLE INCHES OF
SNOW IS POSSIBLE WITH THESE FRONTAL PASSAGES...ALONG WITH BRIEF
PERIODS OF VERY LOW VISIBILITY. HIGH TEMPERATURES TODAY WILL
RANGE FROM THE MID TEENS TO LOWER 20S...AND DEVELOPING WESTERLY
WINDS OF 15 TO 25 MPH WILL RESULT IN WIND CHILL VALUES NEAR ZERO.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1222 PM EST WEDNESDAY...SNOW SQUALL ACTIVITY HAS MOSTLY
ENDED ACROSS EASTERN VERMONT AND HAVE ADJUSTED POPS/WX GRIDS
ACCORDINGLY. CLOUDS ARE VARIABLE ACROSS THE AREA WITH SOME BREAKS
HERE AND THERE...ESPECIALLY IN THE CHAMPLAIN VALLEY. HAVE
ADJUSTED SKY GRIDS TO ACCOUNT FOR THIS AS WELL. BRISK WESTERLY
WINDS CONTINUE WITH COLDER THAN NORMAL MAX TEMPS. PREVIOUS
DISCUSSIONS FOLLOW.
SNOW SQUALL ACTIVITY CURRENTLY MOVING ACROSS THE NORTHERN
CHAMPLAIN VALLEY. THINK THAT CURRENT FORECAST IS IN GOOD SHAPE SO
DID NOT ALTER POPS OR WX AT ALL. THIS AREA OF SQUALLS WILL PUSH
EASTWARD ACROSS VERMONT OVER THE NEXT FEW HOURS AND THEN POPS
DECREASE LATE THIS AFTERNOON AND EVENING. PREVIOUS DISCUSSION
FOLLOWS.
SNOW SHOWER ACTIVITY HAS LOST ORGANIZATION AND STRUCTURE 10-12Z
AS IT MOVED AWAY FROM THE LAKE INDUCED INSTABILITY NEAR LAKE
ONTARIO AND AS FRONTOGENESIS CIRCULATION HAS BEEN DISRUPTED BY
THE STEEP TERRAIN OF THE ADIRONDACKS. EXPECTATION - CONSISTENT
WITH 11Z RAP - IS THAT LIGHT SNOW SHOWERS WILL SHIFT THRU THE
CHAMPLAIN VALLEY NEXT 1-3 HOURS...AND THEN SHOW AN INCREASE IN
INTENSITY ACROSS CENTRAL AND ERN VT AFTER 15Z WITH DEVELOPMENT OF
STEEP LOW- LEVEL LAPSE RATES AND SBCAPE UP TO 100 J/KG. BEST
CHANCE FOR BRIEF MODERATE TO HEAVY SNOW WILL BE ACROSS THE CT
RIVER VALLEY BEFORE ACTIVITY SHIFTS EAST INTO NH. WE/LL SEE A
QUICK DUSTING TO 2" IN SPOTS...HIGHEST CENTRAL/ERN VT DURING THE
MIDDAY HRS. OTHERWISE...LOOKING AT CONTINUED COLD TEMPS WITH
HIGHS IN THE MID TO UPPER TEENS...EXCEPT LOW 20S IN FAR SERN
SECTIONS. INCREASED COLD ADVECTION THIS AFTN MAY ALLOW TEMPS TO
LEVEL OFF AFTER NOON EDT. STEEP LOW-LEVEL LAPSE RATES WILL
CONTRIBUTE TO GUSTY S-SW WINDS IN ADVANCE OF THE FRONT 15-25 MPH
WITH POST- FRONTAL GUSTS TO 30 MPH...SHIFTING INTO THE WEST
FOLLOWING FRONTAL PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 342 AM EST WEDNESDAY...SFC RIDGE BUILDS BRIEFLY ACROSS THE
AREA THIS EVENING AND OVERNIGHT...ALLOWING FOR DIMINISHING WIND
AND A PERIOD OF PARTIAL CLEARING. WITH ARCTIC AIR MASS IN PLACE
(850MB TEMPS -24C)...THE RADIATIONAL COOLING WILL RESULT IN COLD
OVERNIGHT LOWS RANGING FROM NEAR ZERO IN THE CHAMPLAIN VALLEY TO
AROUND 10 BELOW IN THE ADIRONDACKS AND NORTHEAST KINGDOM. TEMPS
MAY LEVEL OFF AFTER MIDNIGHT WITH SOME INCREASE IN CLOUDS IN
ADVANCE OF NEXT SYSTEM.
NEXT SHORTWAVE TROUGH ROTATING AROUND THE SRN PERIPHERY OF PARENT
UPPER LOW ANCHORED ACROSS JAMES BAY WILL TRANSLATE ACROSS THE ERN
GREAT LAKES AROUND 12Z THURSDAY...AND ACROSS THE NORTH COUNTRY
15-21Z TIME FRAME THURSDAY. THIS NEXT SHORTWAVE IS APPEARS
VIGOROUS IN WV IMAGERY AND IN NWP PROJECTIONS...SO QG ASCENT WILL
BE MODERATELY STRONG AS UPR TROUGH APPROACHES DURING THE DAY
THURSDAY. IT APPEARS SBCAPE VALUES WILL BE BETTER ACROSS MOST
SECTIONS OF THE NORTH COUNTRY WITH THIS SYSTEM TOMORROW (AS
OPPOSED TO THE WEAKER ONE TODAY)...WITH 06Z NAM INDICATING
100-150 J/KG ACROSS MUCH OF THE NORTH COUNTRY. ALSO INTERESTING
ARE PROGGED PBL HEIGHTS TO 600MB WITH STEEP LAPSE RATES FROM THE
SFC-12 KFT...A DEFAULT TROPOPAUSE IN THE ARCTIC AIR REGIME.
SO...GOOD CONVECTIVE SNOW POTENTIAL. FRONTOGENETIC FORCING IS NOT
AS WELL ORGANIZED AS WEDNESDAY...SO WOULD ANTICIPATE SMALLER LINE
SEGMENTS AND CONVECTIVE CELLS PRODUCING BRIEF BURSTS OF HEAVIER
SNOW SHOWERS AND POSSIBLE SQUALLS WITH GUSTS 30-35 MPH. A QUICK
1-3" IS POSSIBLE IN SPOTS...AND WILL AGAIN CAUSE SOME BRIEF
TRANSPORTATION HAZARD DUE TO LOW VSBY AND SNOW COVERED ROADS.
MADE MENTION OF THIS AS WELL IN THE MORNING HWO. HIGHS THURSDAY
IN THE UPR TEENS TO LOW 20S. SYSTEM MOVES EAST OF THE AREA
THURSDAY NIGHT WITH JUST A FEW LINGERING MTN FLURRIES. LOWS AGAIN
ZERO TO -10F...BUT LOCALLY COLDER IN THE NRN ADIRONDACKS IF
PARTIAL CLEARING CAN OCCUR LATE.
FRIDAY LOOKS QUIET WITH LOW TO MID LEVEL RIDGING BUILDING INTO
THE REGION FROM THE WEST. SHOULD BE PARTLY TO MOSTLY SUNNY AND
KEPT THE FORECAST DRY. REINFORCED CAA BEHIND THURSDAY/S TROUGH
KEEPS 850MB TEMPS OF -23 TO -24C ACROSS THE REGION FOR FRIDAY.
RATHER INEFFECTIVE SUNSHINE WITH HIGHS IN THE LOW-MID TEENS...AND
LOCALLY 8-9F IN THE NRN ADIRONDACK REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 330 AM EST WEDNESDAY...LITTLE CHANGE FROM PREVIOUS COUPLE
OF FCSTS WITH MID/UPPER LVL TROF PREVAILING ACRS THE NE CONUS AND
SEVERAL OPPORTUNITIES FOR ACCUMULATING SNOWFALL FROM SAT THRU
NEXT TUES. WEAK WARM FRNT FEATURE AND SFC LOW PRES TRACKING TO
OUR NORTH WL PRODUCE LIGHT SNOW SHOWERS ACRS OUR CWA ON SATURDAY.
TEMPS SHOULD WARM INTO THE TEENS AND 20S ON SATURDAY. A DUSTING
TO 2 INCHES LOOKS LIKELY...WITH HIGHEST VALUES ACRS THE MTNS.
MEANWHILE...LATEST 00Z GUIDANCE IS TRENDING FURTHER SOUTH WITH
SYSTEM ON MONDAY/TUESDAY...AND STRONGER WITH SFC HIGH PRES ACRS
SOUTHERN CANADA. THIS WL PROVIDE CWA WITH COLD AND DRY NORTHERLY
WINDS SUNDAY INTO MONDAY ALONG WITH SUPPRESSING BETTER
MOISTURE/LIFT ACRS THE MID ATLANTIC STATES/SNE. HOWEVER...STILL
NOTICING A SHARP NORTH TO SOUTH LLVL THERMAL GRADIENT ACRS OUR
CWA...ALONG WITH SOME ENHANCED 850 TO 500MB RH MOVING FROM SW TO
NE ACRS OUR REGION. THIS MOISTURE COMBINED WITH SEVERAL EMBEDDED
5H VORT IN THE FAST CONFLUENT WESTERLY FLW ALOFT SHOULD BE ENOUGH
TO PRODUCE A LIGHT ACCUMULATING SNOWFALL ACRS THE REGION ON
MONDAY INTO TUESDAY. FURTHERMORE...STILL THINKING MODELS WL SHIFT
BACK NORTH WITH PROGGED SFC LOW PRES TRACK...ESPECIALLY AS
SYSTEM/ENERGY ALOFT ENTERS THE WESTERN CONUS THIS WEEKEND. WL
CONT TO MENTION HIGH CHC POPS FOR THIS TIME PERIOD AND WAIT UNTIL
BETTER AGREEMENT OCCURS IN GUIDANCE BEFORE INCREASING TO LIKELY
POPS. TEMPS WL CONT TO BE TRICKY...ESPECIALLY ASSOCIATED WITH
LLVL CAA ON SUNDAY INTO MONDAY. LATEST GFS IS SHOWING 925MB TEMPS
DROPPING BTWN -22C AND -26C WITH NORTHERLY WINDS. THIS COMBINED
WITH INCREASING HIGH CLOUDS FROM APPROACHING SOUTHERN STREAM
SYSTEM SUPPORTS HIGHS ONLY IN THE SINGLE DIGITS MTNS TO L/M TEEN
VALLEYS. HAVE UNCUT SUPERBLEND BY SEVERAL DEGREES FOR HIGHS...BUT
KEPT CLOSE WITH LOWS RANGING FROM -10F TO +10F...AND HIGHLY
VARIABLE BASED ON CLOUDS/WINDS. SLIGHTLY WARMER TEMPS ARE
ANTICIPATED FOR MONDAY NIGHT INTO TUESDAY...BEFORE ADDITIONAL
COOLING ARRIVES BY THE MID OF NEXT WEEK. OVERALL....TEMPS WL
REMAIN 10 TO 20 DEGREES BLW NORMAL THRU THE PERIOD.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...MAINLY VFR COND THRU FORECAST PERIOD W/
SCT025-040 BKN080 FOR BTV/MPV/PBG/RUT. MVFR -SW FOR RUT POSSIBLE
THRU 00Z THURS W/ 3SM VSBY. AFT 15Z THURSDAY...MVFR COND DEVELOP
WITH -SW AND CEILINGS NEAR BKN025. FOR MSS/SLK...MIX OF VFR DOWN
TO IFR COND AT TIMES W/ BLSN THRU 00Z THURSDAY DROPPING VSBY TO
3-6SM AT TIMES...THEN -SW DEVELOPING FROM LK BAND AS WINDS SHIFTS
W/ VSBY 2-5SM AND CEILINGS BKN020-040. WINDS OVERALL WSW 10-20KTS
WITH GUSTS NEAT 30KTS THRU 00Z THURS THEN 10KTS OR LESS THRU 15Z
THURSDAY THEN BECM SOUTHERLY AT 10-15KTS..
OUTLOOK 18Z THURSDAY THROUGH MONDAY... MAINLY VFR CONDITIONS BTWN
06Z AND 12Z THURSDAY...BEFORE NEXT CLIPPER SYSTEM WITH SNOW
SHOWERS AND IFR/MVFR CONDITIONS DEVELOP BTWN 15Z AND 21Z THURS. A
BRIEF SNOW SQUALL WL ONCE AGAIN BE POSSIBLE ON THURS ASSOCIATED
WITH NEXT SURGE OF ARCTIC AIR. LINGERING UPSLOPE MTN SNOW SHOWERS
WL PREVAIL AT SLK/MPV INTO EARLY FRIDAY MORNING WITH PERIODS OF
IFR/MVFR POSSIBLE...ALONG WITH GUSTY WEST/NORTHWEST WINDS. SFC
HIGH PRES WITH VFR CONDITIONS DEVELOP FRIDAY INTO
SATURDAY...BEFORE NEXT SYSTEM ARRIVES ON SAT AFTN INTO SUNDAY
WITH ADDITIONAL LIGHT SNOW SHOWERS. VFR MONDAY W/ OCNL MVFR -SW.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/NEILES
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...JN/TABER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1224 PM EST WED FEB 26 2014
.SYNOPSIS...
A PROLONGED STRETCH OF COLD WEATHER...WITH TEMPERATURES RUNNING
10 TO 20 DEGREES BELOW AVERAGE...IS EXPECTED TO PERSIST THROUGH
EARLY NEXT WEEK. REINFORCING ARCTIC FRONTS MOVING FROM WEST TO
EAST ACROSS THE NORTH COUNTRY THIS MORNING AND AGAIN DURING THE
MIDDAY THROUGH AFTERNOON HOURS THURSDAY WILL BRING SCATTERED SNOW
SHOWERS AND SNOW SQUALLS. A QUICK DUSTING TO A COUPLE INCHES OF
SNOW IS POSSIBLE WITH THESE FRONTAL PASSAGES...ALONG WITH BRIEF
PERIODS OF VERY LOW VISIBILITY. HIGH TEMPERATURES TODAY WILL
RANGE FROM THE MID TEENS TO LOWER 20S...AND DEVELOPING WESTERLY
WINDS OF 15 TO 25 MPH WILL RESULT IN WIND CHILL VALUES NEAR ZERO.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1222 PM EST WEDNESDAY...SNOW SQUALL ACTIVITY HAS MOSTLY
ENDED ACROSS EASTERN VERMONT AND HAVE ADJUSTED POPS/WX GRIDS
ACCORDINGLY. CLOUDS ARE VARIABLE ACROSS THE AREA WITH SOME BREAKS
HERE AND THERE...ESPECIALLY IN THE CHAMPLAIN VALLEY. HAVE
ADJUSTED SKY GRIDS TO ACCOUNT FOR THIS AS WELL. BRISK WESTERLY
WINDS CONTINUE WITH COLDER THAN NORMAL MAX TEMPS. PREVIOUS
DISCUSSIONS FOLLOW.
SNOW SQUALL ACTIVITY CURRENTLY MOVING ACROSS THE NORTHERN
CHAMPLAIN VALLEY. THINK THAT CURRENT FORECAST IS IN GOOD SHAPE SO
DID NOT ALTER POPS OR WX AT ALL. THIS AREA OF SQUALLS WILL PUSH
EASTWARD ACROSS VERMONT OVER THE NEXT FEW HOURS AND THEN POPS
DECREASE LATE THIS AFTERNOON AND EVENING. PREVIOUS DISCUSSION
FOLLOWS.
SNOW SHOWER ACTIVITY HAS LOST ORGANIZATION AND STRUCTURE 10-12Z
AS IT MOVED AWAY FROM THE LAKE INDUCED INSTABILITY NEAR LAKE
ONTARIO AND AS FRONTOGENETIC CIRCULATION HAS BEEN DISRUPTED BY
THE STEEP TERRAIN OF THE ADIRONDACKS. EXPECTATION - CONSISTENT
WITH 11Z RAP - IS THAT LIGHT SNOW SHOWERS WILL SHIFT THRU THE
CHAMPLAIN VALLEY NEXT 1-3 HOURS...AND THEN SHOW AN INCREASE IN
INTENSITY ACROSS CENTRAL AND ERN VT AFTER 15Z WITH DEVELOPMENT OF
STEEP LOW- LEVEL LAPSE RATES AND SBCAPE UP TO 100 J/KG. BEST
CHANCE FOR BRIEF MODERATE TO HEAVY SNOW WILL BE ACROSS THE CT
RIVER VALLEY BEFORE ACTIVITY SHIFTS EAST INTO NH. WE/LL SEE A
QUICK DUSTING TO 2" IN SPOTS...HIGHEST CENTRAL/ERN VT DURING THE
MIDDAY HRS. OTHERWISE...LOOKING AT CONTINUED COLD TEMPS WITH
HIGHS IN THE MID TO UPPER TEENS...EXCEPT LOW 20S IN FAR SERN
SECTIONS. INCREASED COLD ADVECTION THIS AFTN MAY ALLOW TEMPS TO
LEVEL OFF AFTER NOON EDT. STEEP LOW-LEVEL LAPSE RATES WILL
CONTRIBUTE TO GUSTY S-SW WINDS IN ADVANCE OF THE FRONT 15-25 MPH
WITH POST- FRONTAL GUSTS TO 30 MPH...SHIFTING INTO THE WEST
FOLLOWING FRONTAL PASSAGE.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH FRIDAY/...
AS OF 342 AM EST WEDNESDAY...SFC RIDGE BUILDS BRIEFLY ACROSS THE
AREA THIS EVENING AND OVERNIGHT...ALLOWING FOR DIMINISHING WIND
AND A PERIOD OF PARTIAL CLEARING. WITH ARCTIC AIR MASS IN PLACE
(850MB TEMPS -24C)...THE RADIATIONAL COOLING WILL RESULT IN COLD
OVERNIGHT LOWS RANGING FROM NEAR ZERO IN THE CHAMPLAIN VALLEY TO
AROUND 10 BELOW IN THE ADIRONDACKS AND NORTHEAST KINGDOM. TEMPS
MAY LEVEL OFF AFTER MIDNIGHT WITH SOME INCREASE IN CLOUDS IN
ADVANCE OF NEXT SYSTEM.
NEXT SHORTWAVE TROUGH ROTATING AROUND THE SRN PERIPHERY OF PARENT
UPPER LOW ANCHORED ACROSS JAMES BAY WILL TRANSLATE ACROSS THE ERN
GREAT LAKES AROUND 12Z THURSDAY...AND ACROSS THE NORTH COUNTRY
15-21Z TIME FRAME THURSDAY. THIS NEXT SHORTWAVE IS APPEARS
VIGOROUS IN WV IMAGERY AND IN NWP PROJECTIONS...SO QG ASCENT WILL
BE MODERATELY STRONG AS UPR TROUGH APPROACHES DURING THE DAY
THURSDAY. IT APPEARS SBCAPE VALUES WILL BE BETTER ACROSS MOST
SECTIONS OF THE NORTH COUNTRY WITH THIS SYSTEM TOMORROW (AS
OPPOSED TO THE WEAKER ONE TODAY)...WITH 06Z NAM INDICATING
100-150 J/KG ACROSS MUCH OF THE NORTH COUNTRY. ALSO INTERESTING
ARE PROGGED PBL HEIGHTS TO 600MB WITH STEEP LAPSE RATES FROM THE
SFC-12 KFT...A DEFAULT TROPOPAUSE IN THE ARCTIC AIR REGIME.
SO...GOOD CONVECTIVE SNOW POTENTIAL. FRONTOGENETIC FORCING IS NOT
AS WELL ORGANIZED AS WEDNESDAY...SO WOULD ANTICIPATE SMALLER LINE
SEGMENTS AND CONVECTIVE CELLS PRODUCING BRIEF BURSTS OF HEAVIER
SNOW SHOWERS AND POSSIBLE SQUALLS WITH GUSTS 30-35 MPH. A QUICK
1-3" IS POSSIBLE IN SPOTS...AND WILL AGAIN CAUSE SOME BRIEF
TRANSPORTATION HAZARD DUE TO LOW VSBY AND SNOW COVERED ROADS.
MADE MENTION OF THIS AS WELL IN THE MORNING HWO. HIGHS THURSDAY
IN THE UPR TEENS TO LOW 20S. SYSTEM MOVES EAST OF THE AREA
THURSDAY NIGHT WITH JUST A FEW LINGERING MTN FLURRIES. LOWS AGAIN
ZERO TO -10F...BUT LOCALLY COLDER IN THE NRN ADIRONDACKS IF
PARTIAL CLEARING CAN OCCUR LATE.
FRIDAY LOOKS QUIET WITH LOW TO MID LEVEL RIDGING BUILDING INTO
THE REGION FROM THE WEST. SHOULD BE PARTLY TO MOSTLY SUNNY AND
KEPT THE FORECAST DRY. REINFORCED CAA BEHIND THURSDAY/S TROUGH
KEEPS 850MB TEMPS OF -23 TO -24C ACROSS THE REGION FOR FRIDAY.
RATHER INEFFECTIVE SUNSHINE WITH HIGHS IN THE LOW-MID TEENS...AND
LOCALLY 8-9F IN THE NRN ADIRONDACK REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 330 AM EST WEDNESDAY...LITTLE CHANGE FROM PREVIOUS COUPLE
OF FCSTS WITH MID/UPPER LVL TROF PREVAILING ACRS THE NE CONUS AND
SEVERAL OPPORTUNITIES FOR ACCUMULATING SNOWFALL FROM SAT THRU
NEXT TUES. WEAK WARM FRNT FEATURE AND SFC LOW PRES TRACKING TO
OUR NORTH WL PRODUCE LIGHT SNOW SHOWERS ACRS OUR CWA ON SATURDAY.
TEMPS SHOULD WARM INTO THE TEENS AND 20S ON SATURDAY. A DUSTING
TO 2 INCHES LOOKS LIKELY...WITH HIGHEST VALUES ACRS THE MTNS.
MEANWHILE...LATEST 00Z GUIDANCE IS TRENDING FURTHER SOUTH WITH
SYSTEM ON MONDAY/TUESDAY...AND STRONGER WITH SFC HIGH PRES ACRS
SOUTHERN CANADA. THIS WL PROVIDE CWA WITH COLD AND DRY NORTHERLY
WINDS SUNDAY INTO MONDAY ALONG WITH SUPPRESSING BETTER
MOISTURE/LIFT ACRS THE MID ATLANTIC STATES/SNE. HOWEVER...STILL
NOTICING A SHARP NORTH TO SOUTH LLVL THERMAL GRADIENT ACRS OUR
CWA...ALONG WITH SOME ENHANCED 850 TO 500MB RH MOVING FROM SW TO
NE ACRS OUR REGION. THIS MOISTURE COMBINED WITH SEVERAL EMBEDDED
5H VORT IN THE FAST CONFLUENT WESTERLY FLW ALOFT SHOULD BE ENOUGH
TO PRODUCE A LIGHT ACCUMULATING SNOWFALL ACRS THE REGION ON
MONDAY INTO TUESDAY. FURTHERMORE...STILL THINKING MODELS WL SHIFT
BACK NORTH WITH PROGGED SFC LOW PRES TRACK...ESPECIALLY AS
SYSTEM/ENERGY ALOFT ENTERS THE WESTERN CONUS THIS WEEKEND. WL
CONT TO MENTION HIGH CHC POPS FOR THIS TIME PERIOD AND WAIT UNTIL
BETTER AGREEMENT OCCURS IN GUIDANCE BEFORE INCREASING TO LIKELY
POPS. TEMPS WL CONT TO BE TRICKY...ESPECIALLY ASSOCIATED WITH
LLVL CAA ON SUNDAY INTO MONDAY. LATEST GFS IS SHOWING 925MB TEMPS
DROPPING BTWN -22C AND -26C WITH NORTHERLY WINDS. THIS COMBINED
WITH INCREASING HIGH CLOUDS FROM APPROACHING SOUTHERN STREAM
SYSTEM SUPPORTS HIGHS ONLY IN THE SINGLE DIGITS MTNS TO L/M TEEN
VALLEYS. HAVE UNCUT SUPERBLEND BY SEVERAL DEGREES FOR HIGHS...BUT
KEPT CLOSE WITH LOWS RANGING FROM -10F TO +10F...AND HIGHLY
VARIABLE BASED ON CLOUDS/WINDS. SLIGHTLY WARMER TEMPS ARE
ANTICIPATED FOR MONDAY NIGHT INTO TUESDAY...BEFORE ADDITIONAL
COOLING ARRIVES BY THE MID OF NEXT WEEK. OVERALL....TEMPS WL
REMAIN 10 TO 20 DEGREES BLW NORMAL THRU THE PERIOD.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
THROUGH 06Z THURSDAY...AVIATION CHALLENGE WL BE TIMING OF ARCTIC
BOUNDARY THIS MORNING AND ASSOCIATED SNOW SHOWERS AND POTENTIAL
SNOW SQUALL. CRNT SFC ANALYSIS SHOWS COLD FRNT ACRS THE
SLV/WESTERN DACKS...WITH A NARROW BAND OF ENHANCED SNOW SHOWER
ACTIVITY WITH VIS <1SM. LATEST HRRR/RAP DATA SHOWS THIS BAND
ENTERING THE CPV BTWN 12-15Z THIS MORNING...BUT WEAKENING WITH
SOUTHWEST DOWNSLOPE FLW AND INTERACTION OFF THE DACKS. A BRIEF 20
TO 30 MINUTE WINDOW OF MVFR CONDITIONS WITH VIS AROUND 3SM IN
SNOW SHOWERS WL OCCUR...ALONG WITH A WIND SHIFT TO THE WEST AT
PBG/BTV. THINKING IFR CONDITIONS ASSOCIATED WITH BOUNDARY WL
OCCUR AFT 14Z AT MPV/RUTLAND. IN ADDITION...THE COMBINATION OF
UPSLOPE FLW AND SOME WEAK LAKE ENHANCED MOISTURE WL CONT TO
PRODUCE ON AND OFF IFR VIS IN LIGHT SNOW THRU 14Z THIS MORNING AT
SLK. SOUNDINGS SUPPORT GUSTY WEST/NORTHWEST WINDS OF 10 TO 15
KNOTS WITH GUSTS 25 TO 30 KNOTS DEVELOPING BEHIND FROPA TODAY
BTWN 14Z-22Z TODAY. THESE WINDS WL SLOWLY DISSIPATE BY SUNSET
THIS EVENING.
OUTLOOK 12Z THURSDAY THROUGH SUNDAY... MAINLY VFR CONDITIONS BTWN
06Z AND 12Z THURSDAY...BEFORE NEXT CLIPPER SYSTEM WITH SNOW
SHOWERS AND IFR/MVFR CONDITIONS DEVELOP BTWN 15Z AND 21Z THURS. A
BRIEF SNOW SQUALL WL ONCE AGAIN BE POSSIBLE ON THURS ASSOCIATED
WITH NEXT SURGE OF ARCTIC AIR. LINGERING UPSLOPE MTN SNOW SHOWERS
WL PREVAIL AT SLK/MPV INTO EARLY FRIDAY MORNING WITH PERIODS OF
IFR/MVFR POSSIBLE...ALONG WITH GUSTY WEST/NORTHWEST WINDS. SFC
HIGH PRES WITH VFR CONDITIONS DEVELOP FRIDAY INTO
SATURDAY...BEFORE NEXT SYSTEM ARRIVES ON SAT AFTN INTO SUNDAY
WITH ADDITIONAL LIGHT SNOW SHOWERS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...BANACOS
NEAR TERM...BANACOS/NEILES
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1243 PM EST WED FEB 26 2014
.SYNOPSIS...
LOW PRESSURE WILL STRENGTHEN JUST OFFSHORE THIS MORNING...BRINGING
COLD RAIN TO THE AREA. DRY HIGH PRESSURE WILL BUILD IN FROM THE
WEST TONIGHT...REINFORCED BY A SECOND HIGH BUILDING SOUTHWARD
THURSDAY AND FRIDAY. THIS WILL MAINTAIN BELOW NORMAL TEMPERATURES.
LOW PRESSURE OFFSHORE MAY BRING CLOUDS AND RAIN FRIDAY NIGHT
THROUGH SATURDAY. WARMER TEMPERATURES ARE EXPECTED EARLY NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 12:30 PM WEDNESDAY...LIGHT RAIN AND DRIZZLE CONTINUES TO
MOVE ACROSS THE BULK OF OUR FORECAST AREA ALTHOUGH IT LOOKS LIKE
SOME RELIEF IS IN SIGHT FOR OUR FAR INLAND COUNTIES AS THE BACK
EDGE OF THE PRECIP SHIELD IS NOW IN EVIDENCE. DO NOT EXPECT ANY
MAJOR CHANGES IN THE FORECAST WITH THE AFTERNOON PACKAGE. PREVIOUS
DISCUSSION FOLLOWS:
RAIN IS EXPANDING ACROSS SOUTH CAROLINA THIS MORNING AHEAD OF A
PAIR OF SHORTWAVES. ONE DISTURBANCE IN THE SOUTHERN STREAM NEAR
MOBILE AL WILL CROSS NORTH FLORIDA TODAY... WHILE A POSITIVELY-
TILED SHORTWAVE IN THE NORTHERN STREAM FLOW ACROSS MISSOURI WILL
MOVE ACROSS NC/VA THIS EVENING. AT THE SURFACE A COLD FRONT SLID
SOUTH ACROSS THE AREA YESTERDAY EVENING...AND A SECOND SURGE OF
NORTHERLY WINDS SHOULD OCCUR LATE THIS MORNING AS LOW PRESSURE
DEVELOPS SOUTHEAST OF CAPE FEAR AND DEEPENS AS IT MOVES EAST AND
FARTHER OFFSHORE.
RAIN FALLING ACROSS AL/GA/SC THIS MORNING IS HEADING OUR WAY.
ISENTROPIC LIFT ALONG THE 300-305K THETA SURFACES...APPROXIMATELY
9000-15000 FT ALOFT...APPEARS TO MATCH BEST WITH OBSERVED UPSTREAM
RADAR ECHOES. TRACKING THIS EASTWARD THROUGH THE DAY BRINGS RAIN
INTO THE AREA BETWEEN 8-9 AM...PEAKING IN COVERAGE AND INTENSITY
AROUND NOON...THEN DIMINISHING FROM NW TO SE DURING THE AFTERNOON.
THE NORTHERN EDGE OF MEASURABLE RAIN COULD BE VERY CLOSE TO
BENNETTSVILLE...LUMBERTON AND ELIZABETHTOWN...AND I THEREFORE ONLY
HAVE A FEW HUNDREDTHS OF AN INCH OF RAINFALL FORECAST FOR THESE
LOCATIONS. THE BEST RAINFALL IN MY FORECAST AREA SHOULD BE ALONG
THE SANTEE RIVER IN SOUTH CAROLINA WITH ABOUT THREE-TENTHS
EXPECTED. SKIES MAY BEGIN TO CLEAR ALONG I-95 DURING THE AFTERNOON
AS DRIER AIR WORKS ITS WAY IN ALOFT.
LOW-LEVEL DRY AIR STREAMING SOUTHWARD BEHIND THE SURFACE COLD
FRONT IS PROBABLY NOT DEEP ENOUGH TO AFFECT RAINFALL TOTALS BY
ITSELF... BUT AS RAIN FALLS INTO THIS DRY AIR EVAPORATIONAL
COOLING SHOULD CAUSE A FALLING TREND IN TEMPERATURES DURING THE
LATE MORNING. LOOK FOR NON-TYPICAL TEMPERATURE CURVES AS A
RESULT...PROBABLY SHAPED LIKE A "U" DURING THE DAYLIGHT HOURS
TODAY.
FOR TONIGHT MOISTURE SHOULD THIN FROM THE TOP DOWN WITH SKIES
CLEARING ALONG THE COAST. LIGHT WINDS OVERNIGHT AND A FAIRLY
CHILLY AIRMASS (850 MB TEMPS FALLING TO ZERO TO -4C) SHOULD ALLOW
LOWS TO REACH THE UPPER 20S FOR ALL BUT THE BEACHES. THE MODELS
ARE HINTING AT SOME THIN LOW LEVEL MOISTURE LINGERING ALONG THE
COAST WHICH COULD RESULT IN SOME OVERNIGHT FOG...PARTICULARLY IF
WINDS BECOME CALM.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM WEDNESDAY...AMPLIFIED MID TO UPPER LONGWAVE TROF
ACROSS THE FA ON THU...WILL DE-AMPLIFY SOME FRIDAY INTO FRIDAY
NIGHT. A RE-ENFORCING SHOT OF ARCTIC AND DRIER AIR FROM THE NW
THRU N...WILL PUSH ACROSS THE FA LATE THU AND/OR THU NIGHT. VERY
LITTLE CLOUDS AND NO PCPN WILL ACCOMPANY THIS CFP. WINTER TO
REMAIN ACTIVE WITH RESPECT TO THE COLD TEMPERATURES. HAVE STAYED
AT OR JUST ABOVE THE GFS TEMP MOS GUIDANCE...WHICH PRODUCES
MIN/MAX TEMPS LATE THU THROUGH MUCH OF FRI AT 10 TO POSSIBLY 15
DEGREES BELOW THE CLIMO NORMALS.
THE DRIER AIR THAT WORKS ACROSS THE FA THU AFTN AND AGAIN ON
FRI...COULD BECOME A FIRE HAZARD ESPECIALLY WITH SFC RHS FORECAST
TO DROP TO AROUND 25 PERCENT EACH AFTN. A LIGHT ONSHORE FLOW
DURING FRIDAY MAY HELP KEEP THE COASTAL COUNTIES SLIGHTLY HIGHER
IN THE RH DEPARTMENT. WILL NEED TO MONITOR.
THE MID TO UPPER FLOW BEGINS TO -AMPLIFY SOME FRI NIGHT WITH THE
SOUTHERN STREAM BECOMING A BIT MORE ACTIVE ACROSS THE FORECAST
AREA. TEMPS FRIDAY NITE/SAT MORNING WILL NOT BE AS COLD AS THU
NIGHT/FRI MORNING. AN INVERTED SFC TROF JUST OFF THE CAROLINA
COAST BY SAT MORNING COULD PUSH LOW CLOUDS ONSHORE BY DAYBREAK
SAT. A VERY LOW CHANCE WILL EXIST FOR PATCHY LIGHT RAIN DURING THE
PRE-DAWN SAT HRS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 345 AM WEDNESDAY...THE MID TO UPPER LONGWAVE TROF ACROSS THE
FA WILL CONTINUE TO DE-AMPLIFY THRU THE UPCOMING WEEKEND. THE
SOUTHERN STREAM MID TO UPPER FLOW BECOMES MORE ACTIVE THIS
WEEKEND...WITH UPPER RIDGING LIKELY TO EXTEND ACROSS THE FA FROM
THE GULF OF MEXICO. THIS WILL TEMPORARILY PREVENT POLAR/ARCTIC AIR
WITHIN THE NORTHERN STREAM FROM PUSHING TO THE SOUTHEAST
STATES...INCLUDING THE ILM CWA...DURING THIS WEEKEND. SOME WEAK
FORCING SAT COULD PRODUCE PATCHY LIGHT RAIN ACROSS THE FA AS THE
DYNAMICS FROM A MID TO UPPER S/W TROF CLIPPER TYPE SYSTEM REMAINS
WELL NORTH OF THE FA. DURING SAT...THE COASTAL TROF/FRONT OVER THE
ADJACENT ATL WATERS GETS PULLED TO THE NW-N AND INLAND...ACTING
SIMILAR TO A WARM FRONTAL PASSAGE. TEMPS WILL REBOUND THIS WEEKEND
AND CLIMB TO JUST BELOW NORMAL ON SAT...AND AT OR SLIGHTLY ABOVE
NORMAL ON SUN.
FOR MON INTO TUE...MODELS ARE QUITE DISSIMILAR WITH ONE ANOTHER
WITH RESPECT TO THE UPPER LONGWAVE PATTERN AS WELL AS THE UPPER
SHORT WAVE PATTERN THAT HELPS DEFINE/CONSTRUCT THIS LONGWAVE
PATTERN. AS A RESULT...HAVE STAYED CLOSER TO THE PREVIOUS
FORECAST. HAVE TWEAKED TEMPS SLIGHTLY UPWARD MONDAY AS LOW LEVEL
FLOW FROM THE SOUTH CONTINUES TO PUMP MILD AIR AND HIGHER
DEWPOINTS. WILL HAVE TO KEEP AN EYE ON TUE INTO WED AS A COLD
FRONT DROPS SOUTHWARD WHILE A MID TO UPPER LEVEL SOUTHERN STREAM
S/W TROF APPROACHES FROM THE WSW. WILL CONTINUE TO INDICATE CHANCE
POPS...WITH ABOVE FREEZING LIQUID RAIN RULING THE PCPN TYPE.
&&
.AVIATION /18Z WEDNESDAY THROUGH SUNDAY/...
AS OF 18Z...LIGHT TO MODERATE STRATIFORM RAIN CONTINUES TO MOVE
ACROSS OUR CWA THIS AFTERNOON...WITH THE HEAVIEST/MOST PERSISTENT
RAIN OVER OUR SOUTHERN COUNTIES. THEREFORE...CIGS RANGE FROM VFR
AT KLBT TO MVFR/TEMPO IFR AT KCRE/KMYR. EXPECT MVFR CIGS TO
PREVAIL AT ALL SITES EXCEPT PERHAPS KLBT THIS AFTERNOON. RADAR
TRENDS AND HRRR RUNS INDICATE MOST OF THE PCPN AFTER 18Z WILL BE
FOCUSED ALONG THE COAST...SO WILL MAINTAIN LOWER MVFR CIGS AT
THESE SITES WITH TEMPO IFR AT KCRE AND KMYR. THE WINDS WILL REMAIN
NORTH 6-10 KTS INTO THE EVENING HOURS AS PCPN TAPERS OFF AND VFR
DEVELOPS FROM WEST TO EAST. FCST SOUNDINGS SHOW ENOUGH RESIDUAL
MOISTURE OVERNIGHT TO WARRANT A MENTION OF PATCHY FOG...SO HAVE
ADDED TEMPO MVFR VSBYS FOR ALL SITES BEFORE DAYBREAK. THURSDAY
WILL BE VFR WITH NORTHWEST WINDS AOB 8 KTS.
EXTENDED OUTLOOK...VFR ON FRIDAY. CHANCE OF RAIN/MVFR ON SATURDAY.
MVFR/IFR CIGS/VSBYS POSSIBLE ON SUNDAY. VFR ON MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 12:30 PM WEDNESDAY...HAVE DROPPED THE SMALL CRAFT ADVISORY
FORMERLY IN EFFECT FOR OUR NC WATERS IN FAVOR OF SCEC HEADLINES.
WINDS HAVE STAYED MAINLY IN THE 15 KT RANGE WITH 2 TO 4 FT SEAS SO
FAR. HOWEVER...A SURGE OF WIND THIS AFTERNOON MAY PUSH SEAS UP
INTO THE 3 TO 5 FT RANGE THROUGH THE EVENING HOURS.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 345 AM WEDNESDAY...THURSDAY WILL FEATURE A REINFORCING SHOT
OF POLAR/ARCTIC AIR FROM HIGH PRESSURE THAT WILL FOLLOW AFTER THE
PASSAGE OF THE FRONT THU AFTN OR EARLY EVENING. SCEC OR EVEN SCA
CONDITIONS WILL MAKE AN APPEARANCE AFTER THE COLD FRONTAL
PASSAGE...AND COULD LAST THROUGH MUCH OF FRIDAY AS THE SFC PG TO
REMAIN TIGHTENED ACROSS THE WATERS AS RIDGING FROM THE 1030+ HIGH
CENTERED OVER THE NE STATES FLEXES ITS MUSCLE. SIGNIFICANT SEAS
WILL BUILD RATHER QUICKLY THU NIGHT THRU FRIDAY...WITH NE-E
LOCALLY PRODUCED WIND DRIVEN SHORT PERIOD WAVES DOMINATING THE
SEAS SPECTRUM. WILL HIGHLIGHT THE SCEC/SCA POSSIBILITY IN THE HWO.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 415 AM WEDNESDAY...COASTAL TROF/FRONT WILL DEVELOP OFF THE
CAROLINA COAST SATURDAY...AND LIFT AND/OR SWEEP ACROSS THE AREA
WATERS AND INLAND DURING SAT INTO EARLY SUN. BY SUNDAY...FLOW
ACROSS THE WATERS WILL HAVE VEERED TO THE SE-SSW. THIS A RESULT OF
SFC HIGH PRESSURE TEMPORARILY CENTERED OFFSHORE FROM THE SE U.S.
COAST...AND HAVING BECOME THE PRIMARY DRIVER FOR WINDS ACROSS THE
AREA WATERS. THE ONSHORE FLOW WILL HELP KEEP SIGNIFICANT SEAS
SOMEWHAT ELEVATED BUT LIKELY REMAINING JUST BELOW SCEC/SCA
THRESHOLDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DCH
NEAR TERM...REK/TRA
SHORT TERM...DCH
LONG TERM...DCH
AVIATION...BJR
MARINE...DCH/REK/TRA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
113 PM CST WED FEB 26 2014
.UPDATE...
ISSUED AT 110 PM CST WED FEB 26 2014
HAVE EXTENDED THE WIND ADVISORY INTO THE EVENING. WILL EXPECT A
QUICK DROP IN SPEEDS AROUND 7 PM CST...EVEN A BIT BEFORE THAT IN
THE NORTHWEST...WILLISTON AREA. WILL NEED TO POST ANOTHER WIND
CHILL ADVISORY FOR TONIGHT INTO THURSDAY MORNING. AM WORKING OUT
APPARENT TEMPERATURES NOW TO SEE WHAT AREAS CAN BE LEFT OUT OF
IT.
UPDATE ISSUED AT 1121 AM CST WED FEB 26 2014
WIND SPEEDS WERE RUNNING OVER FORECAST AND I DO NOT SEE WHY THEY
WOULD DROP MUCH THE REST OF THE AFTERNOON. HAVE DECIDED TO EXPAND
THE WIND ADVISORY A COUNTY OR TWO TO THE WEST OF WHAT IT WAS. THIS
WILL NOW PLACE MOHALL...MINOT...GARRISON...STEELE...AND WISHEK IN
THE ADVISORY.
UPDATE ISSUED AT 1035 AM CST WED FEB 26 2014
HAVE UPDATED TO REMOVE THE WIND CHILL ADVISORY. BASED ON
SURFACE OBSERVATION REPORTS AND NORTH DAKOTA DEPARTMENT OF
TRANSPORTATION WEB CAMS...HAVE DECREASED THE PATCHY BLOWING SNOW
FROM THE WEST AND DECREASED THE AREAS OF BLOWING SNOW IN THE EAST.
SOME OF THE CAMERA IMAGES LOOK MILKY BUT NOTHING DECREASING
VISIBILITY TO ANYTHING HAVING AN IMPACT. ROLLA...ROLETTE
COUNTY...WAS REPORTING REDUCED VISIBILITY...ON INTO THE DEVILS
LAKE BASIN.
HAVE ALSO DECREASED CLOUD COVER TODAY WEST INTO CENTRAL.
WILL NEED ANOTHER WIND CHILL ADVISORY FOR WEDNESDAY NIGHT INTO
THURSDAY MORNING.
UPDATE ISSUED AT 637 AM CST WED FEB 26 2014
THE ONGOING WIND CHILL ADVISORY STILL LOOKS GOOD FOR THIS UPDATE.
IN ADDITION...INCREASING ISALLOBARIC WINDS STILL LOOK TO GENERATE
WINDS MEETING WIND ADVISORY CRITERIA EAST THIS AFTERNOON. AS A
RESULT...WILL LEAVE THE CURRENT HEADLINES AS IS FOR THIS UPDATE.
OTHERWISE...THE CURRENT FORECAST IS ON TRACK. NO MAJOR UPDATES WERE
REQUIRED. ONLY ADJUSTED THE HOURLY SENSIBLE WEATHER GRIDS BASED ON
CURRENT OBS/TRENDS. THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CST WED FEB 26 2014
THERE ARE SEVERAL CONCERNS IN THE SHORT TERM PERIOD INCLUDING THE
WIND CHILL ADVISORY THIS MORNING...FOLLOWED BY WINDS FROM MID
MORNING INTO THE AFTERNOON.
EARLY MORNING SURFACE ANALYSIS PLACED HIGH PRESSURE FROM SOUTHERN
NORTH DAKOTA SOUTHWARD INTO THE CENTRAL PLAINS. A COLD FRONT IS
EXPECTED TO MOVE ACROSS THE FORECAST AREA TODAY...BRINGING AN
INCREASE IN NORTHWEST WINDS AS THE FRONT PASSES.
FIRST REGARDING THE WIND CHILL ADVISORY...THE HEADLINE LOOKS TO BE
WELL PLACED. WIND CHILLS SOUTH AND WEST OF THE MISSOURI RIVER HAVE
GENERALLY REMAINED WARMER THAN ADVISORY LEVELS DUE IN PART TO WEAKER
WINDS IN PROXIMITY TO THE SURFACE RIDGE AXIS. WILL LEAVE THE WIND
CHILL ADVISORY IN ITS CURRENT CONFIGURATION SINCE AREAS NORTH AND
EAST OF THE MISSOURI RIVER CONTINUE TO SEE WIND CHILLS OF 25 TO 35
BELOW.
WINDS SPEEDS WILL BE THE NEXT CONCERN AS LOW LEVEL COLD AIR
ADVECTION TAKES HOLD BEHIND THE COLD FRONT. THE STRONGEST
PRESSURE RISE / FALL COUPLET IS ACROSS MINNESOTA INTO EASTERN NORTH
DAKOTA...BUT CLIPS THE EASTERN PART OF THE FORECAST AREA. LOW
LEVEL LAPSE RATES ALSO BECOME STEEPEST FROM THE JAMES RIVER VALLEY
AND EAST. MOMENTUM TRANSFER FROM RAP BUFR SOUNDINGS SUGGEST AREAS
OUTSIDE OF THE ADVISORY COULD BRIEFLY APPROACH ADVISORY
LEVELS...BUT THAT APPEARS SHORT LIVED AND THINK THE HEART OF THE
STRONGEST WINDS SHOULD BE IN THE EASTERN PART OF THE FORECAST
AREA. WILL ONLY MAKE A SMALL ADJUSTMENT TO THE WIND ADVISORY BY
ADDING DICKEY COUNTY WHICH LINES UP WELL WITH SURROUNDING OFFICES.
WILL CONTINUE TO MENTION THE POSSIBILITY OF BLOWING SNOW AND
REDUCED VISIBILITIES...BUT DO NOT THINK VISIBILITIES SHOULD FALL TO
1/2SM OR BELOW...SO DID NOT GO WITH A WINTER WEATHER ADVISORY.
IT WILL BE COLD AGAIN TONIGHT WITH WIND CHILLS AGAIN POTENTIALLY
FALLING TO ADVISORY LEVELS NORTH AND EAST OF THE MISSOURI RIVER.
WITH MULTIPLE HEADLINES ALREADY IN PLACE...DID NOT PUT OUT A
HEADLINE FOR THE WIND CHILLS TONIGHT...BUT EXPECT LATER SHIFTS
WILL HAVE TO CONSIDER THAT POSSIBILITY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 314 AM CST WED FEB 26 2014
WELL BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE EXTENDED
WITH SNOW CHANCES STILL ON TAP FOR THIS WEEKEND.
SOUTHERLY RETURN FLOW WILL INCREASE THURSDAY AHEAD OF AN
APPROACHING COLD FRONT. NOT MUCH IN THE WAY OF WARM AIR ADVECTION
IS FORECAST WITH HIGHS FROM AROUND ZERO EAST TO THE LOW TEENS
WEST. THE COLD FRONT WILL PUSH THROUGH THE STATE FRIDAY MORNING
WITH BREEZY CONDITIONS EXPECTED TO DEVELOP IN ITS WAKE. THE MEDIUM
RANGE MODELS MAINTAIN A DRY FROPA.
WITH THE SURGE OF ARCTIC AIR...A BAROCLINIC ZONE IS STILL PROGGED
TO SET UP OVER SOUTHWESTERN NORTH DAKOTA FRIDAY AFTERNOON/NIGHT.
THIS SHOULD PROVIDE ENOUGH ELEVATED CONVERGENCE TO GENERATE A
CHANCE OF SNOW SOUTHWEST LATE FRIDAY INTO SATURDAY.
THE MEDIUM RANGE MODELS BEGIN TO DIVERGE WITH RESPECT TO THE
SYNOPTIC PATTERN OVER THE NORTHERN PLAINS SUNDAY THROUGH THE END
OF THE PERIOD. THE LATEST GFS IS DEEPER AND MORE PROGRESSIVE WITH
AN UPPER LOW OVER THE CANADIAN ROCKIES SATURDAY MOVING THROUGH THE
NORTHERN PLAINS SUNDAY. HOWEVER...THE LATEST ECMWF PINCHES OFF THE
UPPER LOW OVER THE CANADIAN ROCKIES WHERE IT BECOMES STATIONARY
THROUGH THE END OF THE PERIOD. GIVEN THE MODEL TO MODEL AND RUN TO
RUN INCONSISTENCIES...FORECAST A BLEND OF SOLUTIONS WITH SNOW
CHANCES SUNDAY...AND DRY CONDITIONS OVER WESTERN AND CENTRAL NORTH
DAKOTA MONDAY AND TUESDAY. REGARDLESS OF WHICH SOLUTION
VERIFIES...WELL BELOW TEMPERATURES ARE STILL FORECAST THROUGH THE
END OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 110 PM CST WED FEB 26 2014
STRONG NORTHWEST WINDS ARE FORECAST UNTIL 01Z/27TH...AFTER WHICH
TIME THEY WILL BE RAPIDLY DECREASING. STRONGEST WINDS WILL OCCUR
FROM KMOT TO KJMS WHERE PATCHY BLOWING SNOW IS POSSIBLE BUT WITH NO
SIGNIFICANT REDUCTION IN VISIBILITY. VFR CIGS AND VSBYS WILL
CONTINUE THROUGH THE TAF VALID PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 7 PM CST THIS EVENING FOR NDZ002>005-011>013-
021>023-025-036-037-047-048-050-051.
&&
$$
UPDATE...JPM
SHORT TERM...CK
LONG TERM...TM
AVIATION...JPM/ACOOP
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1124 AM CST WED FEB 26 2014
.UPDATE...
ISSUED AT 1121 AM CST WED FEB 26 2014
WIND SPEEDS WERE RUNNING OVER FORECAST AND I DO NOT SEE WHY THEY
WOULD DROP MUCH THE REST OF THE AFTERNOON. HAVE DECIDED TO EXPAND
THE WIND ADVISORY A COUNTY OR TWO TO THE WEST OF WHAT IT WAS. THIS
WILL NOW PLACE MOHALL...MINOT...GARRISON...STEELE...AND WISHEK IN
THE ADVISORY.
UPDATE ISSUED AT 1035 AM CST WED FEB 26 2014
HAVE UPDATED TO REMOVE THE WIND CHILL ADVISORY. BASED ON
SURFACE OBSERVATION REPORTS AND NORTH DAKOTA DEPARTMENT OF
TRANSPORTATION WEB CAMS...HAVE DECREASED THE PATCHY BLOWING SNOW
FROM THE WEST AND DECREASED THE AREAS OF BLOWING SNOW IN THE EAST.
SOME OF THE CAMERA IMAGES LOOK MILKY BUT NOTHING DECREASING
VISIBILITY TO ANYTHING HAVING AN IMPACT. ROLLA...ROLETTE
COUNTY...WAS REPORTING REDUCED VISIBILITY...ON INTO THE DEVILS
LAKE BASIN.
HAVE ALSO DECREASED CLOUD COVER TODAY WEST INTO CENTRAL.
WILL NEED ANOTHER WIND CHILL ADVISORY FOR WEDNESDAY NIGHT INTO
THURSDAY MORNING.
UPDATE ISSUED AT 637 AM CST WED FEB 26 2014
THE ONGOING WIND CHILL ADVISORY STILL LOOKS GOOD FOR THIS UPDATE.
IN ADDITION...INCREASING ISALLOBARIC WINDS STILL LOOK TO GENERATE
WINDS MEETING WIND ADVISORY CRITERIA EAST THIS AFTERNOON. AS A
RESULT...WILL LEAVE THE CURRENT HEADLINES AS IS FOR THIS UPDATE.
OTHERWISE...THE CURRENT FORECAST IS ON TRACK. NO MAJOR UPDATES WERE
REQUIRED. ONLY ADJUSTED THE HOURLY SENSIBLE WEATHER GRIDS BASED ON
CURRENT OBS/TRENDS. THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CST WED FEB 26 2014
THERE ARE SEVERAL CONCERNS IN THE SHORT TERM PERIOD INCLUDING THE
WIND CHILL ADVISORY THIS MORNING...FOLLOWED BY WINDS FROM MID
MORNING INTO THE AFTERNOON.
EARLY MORNING SURFACE ANALYSIS PLACED HIGH PRESSURE FROM SOUTHERN
NORTH DAKOTA SOUTHWARD INTO THE CENTRAL PLAINS. A COLD FRONT IS
EXPECTED TO MOVE ACROSS THE FORECAST AREA TODAY...BRINGING AN
INCREASE IN NORTHWEST WINDS AS THE FRONT PASSES.
FIRST REGARDING THE WIND CHILL ADVISORY...THE HEADLINE LOOKS TO BE
WELL PLACED. WIND CHILLS SOUTH AND WEST OF THE MISSOURI RIVER HAVE
GENERALLY REMAINED WARMER THAN ADVISORY LEVELS DUE IN PART TO WEAKER
WINDS IN PROXIMITY TO THE SURFACE RIDGE AXIS. WILL LEAVE THE WIND
CHILL ADVISORY IN ITS CURRENT CONFIGURATION SINCE AREAS NORTH AND
EAST OF THE MISSOURI RIVER CONTINUE TO SEE WIND CHILLS OF 25 TO 35
BELOW.
WINDS SPEEDS WILL BE THE NEXT CONCERN AS LOW LEVEL COLD AIR
ADVECTION TAKES HOLD BEHIND THE COLD FRONT. THE STRONGEST
PRESSURE RISE / FALL COUPLET IS ACROSS MINNESOTA INTO EASTERN NORTH
DAKOTA...BUT CLIPS THE EASTERN PART OF THE FORECAST AREA. LOW
LEVEL LAPSE RATES ALSO BECOME STEEPEST FROM THE JAMES RIVER VALLEY
AND EAST. MOMENTUM TRANSFER FROM RAP BUFR SOUNDINGS SUGGEST AREAS
OUTSIDE OF THE ADVISORY COULD BRIEFLY APPROACH ADVISORY
LEVELS...BUT THAT APPEARS SHORT LIVED AND THINK THE HEART OF THE
STRONGEST WINDS SHOULD BE IN THE EASTERN PART OF THE FORECAST
AREA. WILL ONLY MAKE A SMALL ADJUSTMENT TO THE WIND ADVISORY BY
ADDING DICKEY COUNTY WHICH LINES UP WELL WITH SURROUNDING OFFICES.
WILL CONTINUE TO MENTION THE POSSIBILITY OF BLOWING SNOW AND
REDUCED VISIBILITIES...BUT DO NOT THINK VISIBILITIES SHOULD FALL TO
1/2SM OR BELOW...SO DID NOT GO WITH A WINTER WEATHER ADVISORY.
IT WILL BE COLD AGAIN TONIGHT WITH WIND CHILLS AGAIN POTENTIALLY
FALLING TO ADVISORY LEVELS NORTH AND EAST OF THE MISSOURI RIVER.
WITH MULTIPLE HEADLINES ALREADY IN PLACE...DID NOT PUT OUT A
HEADLINE FOR THE WIND CHILLS TONIGHT...BUT EXPECT LATER SHIFTS
WILL HAVE TO CONSIDER THAT POSSIBILITY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 314 AM CST WED FEB 26 2014
WELL BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE EXTENDED
WITH SNOW CHANCES STILL ON TAP FOR THIS WEEKEND.
SOUTHERLY RETURN FLOW WILL INCREASE THURSDAY AHEAD OF AN
APPROACHING COLD FRONT. NOT MUCH IN THE WAY OF WARM AIR ADVECTION
IS FORECAST WITH HIGHS FROM AROUND ZERO EAST TO THE LOW TEENS
WEST. THE COLD FRONT WILL PUSH THROUGH THE STATE FRIDAY MORNING
WITH BREEZY CONDITIONS EXPECTED TO DEVELOP IN ITS WAKE. THE MEDIUM
RANGE MODELS MAINTAIN A DRY FROPA.
WITH THE SURGE OF ARCTIC AIR...A BAROCLINIC ZONE IS STILL PROGGED
TO SET UP OVER SOUTHWESTERN NORTH DAKOTA FRIDAY AFTERNOON/NIGHT.
THIS SHOULD PROVIDE ENOUGH ELEVATED CONVERGENCE TO GENERATE A
CHANCE OF SNOW SOUTHWEST LATE FRIDAY INTO SATURDAY.
THE MEDIUM RANGE MODELS BEGIN TO DIVERGE WITH RESPECT TO THE
SYNOPTIC PATTERN OVER THE NORTHERN PLAINS SUNDAY THROUGH THE END
OF THE PERIOD. THE LATEST GFS IS DEEPER AND MORE PROGRESSIVE WITH
AN UPPER LOW OVER THE CANADIAN ROCKIES SATURDAY MOVING THROUGH THE
NORTHERN PLAINS SUNDAY. HOWEVER...THE LATEST ECMWF PINCHES OFF THE
UPPER LOW OVER THE CANADIAN ROCKIES WHERE IT BECOMES STATIONARY
THROUGH THE END OF THE PERIOD. GIVEN THE MODEL TO MODEL AND RUN TO
RUN INCONSISTENCIES...FORECAST A BLEND OF SOLUTIONS WITH SNOW
CHANCES SUNDAY...AND DRY CONDITIONS OVER WESTERN AND CENTRAL NORTH
DAKOTA MONDAY AND TUESDAY. REGARDLESS OF WHICH SOLUTION
VERIFIES...WELL BELOW TEMPERATURES ARE STILL FORECAST THROUGH THE
END OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1035 AM CST WED FEB 26 2014
VFR AT ALL TAF SITES THROUGH THE FORECAST VALID PERIOD UNDER A
MOSTLY CLEAR SKY. THE MAIN CONCERN THROUGH 02Z/27TH IS GUSTY
NORTHWEST WINDS...ESPECIALLY OVER THE EASTERN HALF OF NORTH DAKOTA.
SPEEDS WILL BE AROUND 25 KNOTS...GUSTING 35 KNOTS. THIS WILL
CREATE PATCHES OF BLOWING SNOW. NOTE THAT KMOT HAS BEEN REPORTING
-SN BUT THAT IS NOT FALLING SNOW...IT IS SNOW BEING BLOWN INTO THE
ASOS SENSOR. VSBY AT KMOT WAS STILL P6SM. SIMILAR THING COULD
HAPPEN AT KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ002>005-011>013-
021>023-025-036-037-047-048-050-051.
&&
$$
UPDATE...JPM
SHORT TERM...CK
LONG TERM...TM
AVIATION...JPM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1043 AM CST WED FEB 26 2014
.UPDATE...
ISSUED AT 1035 AM CST WED FEB 26 2014
HAVE UPDATED TO REMOVE THE WIND CHILL ADVISORY. BASED ON
SURFACE OBSERVATION REPORTS AND NORTH DAKOTA DEPARTMENT OF
TRANSPORTATION WEB CAMS...HAVE DECREASED THE PATCHY BLOWING SNOW
FROM THE WEST AND DECREASED THE AREAS OF BLOWING SNOW IN THE EAST.
SOME OF THE CAMERA IMAGES LOOK MILKY BUT NOTHING DECREASING
VISIBILITY TO ANYTHING HAVING AN IMPACT. ROLLA...ROLETTE
COUNTY...WAS REPORTING REDUCED VISIBILITY...ON INTO THE DEVILS
LAKE BASIN.
HAVE ALSO DECREASED CLOUD COVER TODAY WEST INTO CENTRAL.
WILL NEED ANOTHER WIND CHILL ADVISORY FOR WEDNESDAY NIGHT INTO
THURSDAY MORNING.
UPDATE ISSUED AT 637 AM CST WED FEB 26 2014
THE ONGOING WIND CHILL ADVISORY STILL LOOKS GOOD FOR THIS UPDATE.
IN ADDITION...INCREASING ISALLOBARIC WINDS STILL LOOK TO GENERATE
WINDS MEETING WIND ADVISORY CRITERIA EAST THIS AFTERNOON. AS A
RESULT...WILL LEAVE THE CURRENT HEADLINES AS IS FOR THIS UPDATE.
OTHERWISE...THE CURRENT FORECAST IS ON TRACK. NO MAJOR UPDATES WERE
REQUIRED. ONLY ADJUSTED THE HOURLY SENSIBLE WEATHER GRIDS BASED ON
CURRENT OBS/TRENDS. THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 314 AM CST WED FEB 26 2014
THERE ARE SEVERAL CONCERNS IN THE SHORT TERM PERIOD INCLUDING THE
WIND CHILL ADVISORY THIS MORNING...FOLLOWED BY WINDS FROM MID
MORNING INTO THE AFTERNOON.
EARLY MORNING SURFACE ANALYSIS PLACED HIGH PRESSURE FROM SOUTHERN
NORTH DAKOTA SOUTHWARD INTO THE CENTRAL PLAINS. A COLD FRONT IS
EXPECTED TO MOVE ACROSS THE FORECAST AREA TODAY...BRINGING AN
INCREASE IN NORTHWEST WINDS AS THE FRONT PASSES.
FIRST REGARDING THE WIND CHILL ADVISORY...THE HEADLINE LOOKS TO BE
WELL PLACED. WIND CHILLS SOUTH AND WEST OF THE MISSOURI RIVER HAVE
GENERALLY REMAINED WARMER THAN ADVISORY LEVELS DUE IN PART TO WEAKER
WINDS IN PROXIMITY TO THE SURFACE RIDGE AXIS. WILL LEAVE THE WIND
CHILL ADVISORY IN ITS CURRENT CONFIGURATION SINCE AREAS NORTH AND
EAST OF THE MISSOURI RIVER CONTINUE TO SEE WIND CHILLS OF 25 TO 35
BELOW.
WINDS SPEEDS WILL BE THE NEXT CONCERN AS LOW LEVEL COLD AIR
ADVECTION TAKES HOLD BEHIND THE COLD FRONT. THE STRONGEST
PRESSURE RISE / FALL COUPLET IS ACROSS MINNESOTA INTO EASTERN NORTH
DAKOTA...BUT CLIPS THE EASTERN PART OF THE FORECAST AREA. LOW
LEVEL LAPSE RATES ALSO BECOME STEEPEST FROM THE JAMES RIVER VALLEY
AND EAST. MOMENTUM TRANSFER FROM RAP BUFR SOUNDINGS SUGGEST AREAS
OUTSIDE OF THE ADVISORY COULD BRIEFLY APPROACH ADVISORY
LEVELS...BUT THAT APPEARS SHORT LIVED AND THINK THE HEART OF THE
STRONGEST WINDS SHOULD BE IN THE EASTERN PART OF THE FORECAST
AREA. WILL ONLY MAKE A SMALL ADJUSTMENT TO THE WIND ADVISORY BY
ADDING DICKEY COUNTY WHICH LINES UP WELL WITH SURROUNDING OFFICES.
WILL CONTINUE TO MENTION THE POSSIBILITY OF BLOWING SNOW AND
REDUCED VISIBILITIES...BUT DO NOT THINK VISIBILITIES SHOULD FALL TO
1/2SM OR BELOW...SO DID NOT GO WITH A WINTER WEATHER ADVISORY.
IT WILL BE COLD AGAIN TONIGHT WITH WIND CHILLS AGAIN POTENTIALLY
FALLING TO ADVISORY LEVELS NORTH AND EAST OF THE MISSOURI RIVER.
WITH MULTIPLE HEADLINES ALREADY IN PLACE...DID NOT PUT OUT A
HEADLINE FOR THE WIND CHILLS TONIGHT...BUT EXPECT LATER SHIFTS
WILL HAVE TO CONSIDER THAT POSSIBILITY.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 314 AM CST WED FEB 26 2014
WELL BELOW NORMAL TEMPERATURES WILL CONTINUE THROUGH THE EXTENDED
WITH SNOW CHANCES STILL ON TAP FOR THIS WEEKEND.
SOUTHERLY RETURN FLOW WILL INCREASE THURSDAY AHEAD OF AN
APPROACHING COLD FRONT. NOT MUCH IN THE WAY OF WARM AIR ADVECTION
IS FORECAST WITH HIGHS FROM AROUND ZERO EAST TO THE LOW TEENS
WEST. THE COLD FRONT WILL PUSH THROUGH THE STATE FRIDAY MORNING
WITH BREEZY CONDITIONS EXPECTED TO DEVELOP IN ITS WAKE. THE MEDIUM
RANGE MODELS MAINTAIN A DRY FROPA.
WITH THE SURGE OF ARCTIC AIR...A BAROCLINIC ZONE IS STILL PROGGED
TO SET UP OVER SOUTHWESTERN NORTH DAKOTA FRIDAY AFTERNOON/NIGHT.
THIS SHOULD PROVIDE ENOUGH ELEVATED CONVERGENCE TO GENERATE A
CHANCE OF SNOW SOUTHWEST LATE FRIDAY INTO SATURDAY.
THE MEDIUM RANGE MODELS BEGIN TO DIVERGE WITH RESPECT TO THE
SYNOPTIC PATTERN OVER THE NORTHERN PLAINS SUNDAY THROUGH THE END
OF THE PERIOD. THE LATEST GFS IS DEEPER AND MORE PROGRESSIVE WITH
AN UPPER LOW OVER THE CANADIAN ROCKIES SATURDAY MOVING THROUGH THE
NORTHERN PLAINS SUNDAY. HOWEVER...THE LATEST ECMWF PINCHES OFF THE
UPPER LOW OVER THE CANADIAN ROCKIES WHERE IT BECOMES STATIONARY
THROUGH THE END OF THE PERIOD. GIVEN THE MODEL TO MODEL AND RUN TO
RUN INCONSISTENCIES...FORECAST A BLEND OF SOLUTIONS WITH SNOW
CHANCES SUNDAY...AND DRY CONDITIONS OVER WESTERN AND CENTRAL NORTH
DAKOTA MONDAY AND TUESDAY. REGARDLESS OF WHICH SOLUTION
VERIFIES...WELL BELOW TEMPERATURES ARE STILL FORECAST THROUGH THE
END OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1035 AM CST WED FEB 26 2014
VFR AT ALL TAF SITES THROUGH THE FORECAST VALID PERIOD UNDER A
MOSTLY CLEAR SKY. THE MAIN CONCERN THROUGH 02Z/27TH IS GUSTY
NORTHWEST WINDS...ESPECIALLY OVER THE EASTERN HALF OF NORTH DAKOTA.
SPEEDS WILL BE AROUND 25 KNOTS...GUSTING 35 KNOTS. THIS WILL
CREATE PATCHES OF BLOWING SNOW. NOTE THAT KMOT HAS BEEN REPORTING
-SN BUT THAT IS NOT FALLING SNOW...IT IS SNOW BEING BLOWN INTO THE
ASOS SENSOR. VSBY AT KMOT WAS STILL P6SM. SIMILAR THING COULD
HAPPEN AT KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR NDZ004-005-012-013-
022-023-025-037-048-051.
&&
$$
UPDATE...JPM
SHORT TERM...CK
LONG TERM...TM
AVIATION...JPM
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1256 PM EST WED FEB 26 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE REGION THIS MORNING AND USHER IN COOLER
CANADIAN HIGH PRESSURE. THIS HIGH WILL BECOME REINFORCED FROM THE
NORTH ON FRIDAY AND LINGER INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM EST WEDNESDAY...FORECAST REMAINS ON TRACK AS SHOWER
ACTIVITY CONTINUES TO EXIT TO THE SOUTHEAST. THUS...ASIDE FROM
ADJUSTING TEMPERATURES AND DEWPOINTS TO REFLECT LATEST OBSERVATIONAL
TRENDS...NO OTHER CHANGES WERE MADE WITH THIS UPDATE. LOW RH AND
INCREASING WINDS CONTINUE TO PRESENT MODEST FIRE WX CONCERNS
TOMORROW...ESPECIALLY IN THE HIGH TERRAIN OF NC. PLEASE REFER TO
FIRE WX SECTION OF AFD FOR DETAILS.
PREVIOUS DISCUSSION...
AS OF 615 AM EST...SHORTWAVE ROTATES THRU THE ERN CONUS UPPER TROUGH
THIS MORNING...WITH COLD FRONT USHERING IN HIGH PRESSURE AND A MUCH
COLDER AIRMASS OVER THE COURSE OF THE DAY. WESTERLY MIDLEVEL WINDS
PRIOR TO THE FRONT WILL PROVIDE SLIGHT WARM ADVECTION AND ASSOCIATED
LIFT...BUT MODELS SEEM TO RESPOND MORE TO INTERACTION OF FRONTAL
CONVERGENCE WITH INCUMBENT MOISTURE ACRS GA/SC.
MESO MODELS INCLUDING LATEST COUPLE HRRR RUNS CONFINE QPF RESPONSE
WELL SOUTH OF I-85. GFS AND SREF HOWEVER FAVOR MORE OF THE PRECIP
DEVELOPING ACRS THE UPSTATE. THIS IS NOT WELL SUPPORTED BY RADAR
TRENDS SO FAR THIS AM. BEST POPS STILL LOOK TO BE IN 12-15Z
TIMEFRAME AS THE FRONT ENTERS THE LOWER PIEDMONT. DESPITE LACK OF
MODEL RESPONSE...GIVEN THE SETUP IT IS REASONABLE TO INCLUDE SCHC
POPS A BIT FURTHER NORTH...WITH TIGHT THERMAL GRADIENT ACRS THE FA
IN EXIT REGION OF THE SHORTWAVE THRU THE MRNG. NW FLOW STILL LOOKS
TO HAVE SUFFICIENT ORIENTATION AND MOISTURE TO PRODUCE BRIEF LIGHT
SNOW IN THE MTNS...BUT LATEST GUIDANCE SUPPORTS ONLY CHC POPS AND
MINIMAL ACCUMS. IN FACT THIS MAY BE A BIT OPTIMISTIC GIVEN LACK OF
RADAR RETURNS OVER EAST TN.
CLEARING OF THE LOW-MID CLOUDS ASSOCIATED WITH THE FRONTAL ZONE IS
EXPECTED TO RAPIDLY OCCUR THRU MIDDAY LEAVING A MOSTLY SUNNY AFTN.
GIVEN THE COLD AND NEWLY ARRIVED AIR MASS BUT ALSO ABUNDANT SUNSHINE
AND SLIGHT DOWNSLOPING...A BLEND OF MOS AND RAW TEMPS IS APPROPRIATE
WHICH CONTINUES TO SUPPORT TEMPS A COUPLE CATEGORIES BELOW NORMAL
EXCEPT IN THE HIGH TERRAIN WHERE MANY AREAS WON/T RISE OUT OF THE
30S. TONIGHT...WINDS BECOME LIGHT AND SKIES REMAIN CLEAR AND LOWS
DROP INTO THE TEENS MTNS AND 20S PIEDMONT.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
AS OF 200 AM WEDNESDAY...A DRY COLD FRONT WILL CROSS THE REGION
DURING THE DAY ON THURSDAY...LOWERING DEWPOINTS EVEN FURTHER. WITH
BREEZY TO WINDY CONDITIONS OVER THE NC MTNS AND FOOTHILLS...THE
POTENTIAL EXITS FOR CRITICAL FIRE WEATHER CONDITIONS. PLEASE SEE THE
FIRE WEATHER PART OF THE DISCUSSION FOR MORE DETAILS.
OTHERWISE...DRY COLD AIR DAMMING WILL BECOME MORE PRONOUNCED OVER
THE REGION THURSDAY NIGHT AND FRIDAY. THE THICKNESS TROUGH IN THE
LEE SHOULD RESULT IN COLD CONDITIONS THU NIGHT AND WELL BELOW
NORMAL TEMPERATURES ON FRIDAY. THURSDAY WE SHOULD SEE CLEAR...BLUE
SKIES. SKIES REMAIN CLEAR THU NIGHT...BUT HIGH CLOUDS SHOULD BE ON
THE INCREASE DURING THE DAY ON FRIDAY. A FAST MOVING SHORT WAVE WILL
CROSS THE NC ZONES FRI NIGHT. MOST OF THE FORCING WITH THE WAVE
PASSES NORTH OF THE FORECAST AREA. HOWEVER...LLVL WARM ADVECTION
OVER THE WRN PIEDMONT MAY SUPPORT SOME PATCHY LIGHT PCPN OVER THE
ERN ZONES. THERE ALSO APPEARS TO BE SUFFICIENT FORCING ACROSS THE
MTNS TO SUPPORT CHANCE POPS AS WELL. I USED THE BOURGOUIN TECHNIQUE
WHICH STARTS PCPN AS RAIN EARLY FRIDAY NIGHT WITH A TRANSITION TO
SNOW AND THEN FREEZING RAIN OVER MOST OF THE NC ZONES. UNDERSTAND
THAT QPF IS VERY LIGHT WITH THIS EVENT AND POPS ARE GENERALLY IN THE
LOW CHANCE TO SLIGHT CHANCE RANGE. THAT/S TO SAY...THE WEATHER GRID
LOOKS SCARIER THAN THE REALITY OF THE SITUATION. STILL...WE COULD
SEE A LIGHT ACCUMULATION OF SNOW OR ICE NORTH OF I40 AND OVER PARTS
OF THE NC MTNS FRIDAY NIGHT...BUT THE PCPN IS SO LIGHT I DON/T EVEN
PLAN TO MENTION IT IN THE HWO ATTM.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AS OF 230 AM EST WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z
ON SUNDAY WITH WHATS LEFT OF AN UPPER SHORTWAVE MOVING OUT OVER THE
ATLANTIC AND UPPER RIDGING BUILDING OVER THE GULF OF MEXICO AND SE
CONUS. THE LONG RANGE MODELS ARE TRYING TO CLOSE OFF AN H5 LOW OVER
EXTREME SOUTHERN BRITISH COLUMBIA EARLY SUNDAY WITH THE NEWER RUN OF
THE GFS BEING MORE PRONOUNCED. AS WE MOVE INTO MONDAY...HEIGHTS
BEGIN TO LOWER AGAIN AS A COMPLEX UPPER TROF PATTERN MOVES SE ACROSS
THE FAR NORTHERN PLAINS AND INTO THE GREAT LAKES REGION. THE MODELS
INDICATE THAT THE MAIN TROF AXIS WILL LIKELY BE NORTH OF THE
CAROLINAS BY LATE TUES/EARLY WED AND PERSIST OVER THE REGION THRU
DAY 7. OVERALL...THE LONG RANGE MODELS APPEAR TO BE COMING INTO
BETTER AGREEMENT WRT THE PROGRESSION AND TIMING OF THIS UPPER TROF
SYSTEM...WITH THE GFS BEING MORE AMPLIFIED AND BRINGING THE SYSTEM
FARTHER SOUTH COMPARED TO THE ECMWF.
AT THE SFC...THE HIGH CENTERED OVER NEW ENGLAND HELPING TO PRODUCE A
COLD AIR WEDGE PATTERN OVER THE CAROLINAS WILL BE MOVING WELL OFF
THE COAST BY EARLY SUN. THE MODELS CONTINUE TO MAINTAIN ANOTHER
BERMUDA TYPE HIGH CENTERED TO OUR EAST ON SUN AND EARLY MON. THEY
ALSO SPIN UP A LOW OVER THE SOUTHERN MISS RIVER VALLEY EARLY MON AND
MOVE IT OVER THE CWFA BY MON AFTERNOON. WHAT HAPPENS OVER THE NEXT
24 TO 36HRS VARIES CONSIDERABLY BETWEEN THE GFS AND ECMWF. THE GFS
KEEPS THE LOW AND ITS ASSOCIATED REGION OF BROAD AND DEEP MOISTURE
OVER THE FCST AREA THRU TUES AFTERNOON BEFORE MOVING IT NE AND
OFFSHORE...WHILE THE ECMWF AND CMC MOVE IT OFFSHORE BY MON EVENING
WITH DRIER HIGH PRESSURE SPREADING OVER THE REGION IN ITS WAKE ON
TUES. BOTH MODELS AGREE THAT THE REMAINDER OF THE FCST SHOULD BE DRY
HIGH PRESSURE OVER THE AREA ON WED. TEMPS WILL START OUT WELL ABOVE
NORMAL FOR EARLY MARCH WITH HIGHS ON SUN IN THE MID 60S FOR THE
LOWER ELEVATIONS AND UPPER 50S TO LOW 60S FOR THE HIGHER TERRAIN. BY
THE END OF THE PERIOD...I ANTICIPATE THAT VALUES WILL COOL BACK DOWN
BELOW CLIMATOLOGY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD AS COLD AIR
ADVECTION PREVAILS AND HIGH PRESSURE BUILDS. BKN MID/HIGH LEVEL
CIRRUS WILL PERSIST THROUGH THE AFTERNOON AMIDST NE WINDS AROUND
6-8KTS. A SECOND MID LEVEL WAVE WILL DIVE ACROSS THE REGION
OVERNIGHT LEADING DEVELOPMENT OF A WEAK LOW LEVEL TROF. INCREASING
SATURATION ALONG THIS BOUNDARY WILL LEAD TO DEVELOPMENT OF LOW VFR
CIGS THROUGH APPROXIMATELY 08Z BEFORE SCATTERING OUT. SKIES WILL
CLEAR BY MID/LATE MORNING LEADING TO FAIR WEATHER FOR THURSDAY. AS
FOR WINDS...EXPECTING FLOW TO BACK NORTHWESTERLY AS THE ABOVE
MENTIONED WAVE AND ASSOCIATED WEAK SURFACE BOUNDARY PASS THROUGH THE
REGION BY AROUND 15Z THURSDAY MORNING.
ELSEWHERE...MUCH THE SAME AS KCLT ABOVE AS VFR CONDITIONS WILL
PREVAIL THROUGH THE PERIOD. BKN MID/HIGH LEVEL CIRRUS WILL PERSIST
THROUGH THE AFTERNOON AT ALL SITES EXCEPT FOR KAVL WHERE SKIES SCT
OUT. OTHERWISE...LOW VFR CIGS ARE POSSIBLE AT KGSP/KGMU ASSOCIATED
WITH THE ABOVE MENTIONED 850 TROF AXIS OVERNIGHT. ALL OTHER SITES
WILL REMAIN SCT/FEW AROUND 6KFT. LIGHT WINDS WILL BACK
NORTHWESTERLY THURSDAY MORNING AT ALL SITES BEHIND THE PASSAGE OF
THE APPROACHING WEAK SFC BOUNDARY...WITH THE EXCEPTION OF KAVL WHICH
REMAINS NORTHWESTERLY THROUGH THE PERIOD. WINDS WILL INCREASE
ACROSS THE REGION TO AROUND THE 8-10KTS RANGE LATE THURSDAY MORNING
AT ALL SITES EXCEPT KAVL WHERE SUSTAINED FLOW AROUND THE 12KT RANGE
WITH 20-25KT GUSTS IS EXPECTED.
OUTLOOK...DRY/VFR THU-FRI...BUT PRECIPITATION AND ASSOCIATED
RESTRICTIONS ARE POSSIBLE EARLY SAT.
CONFIDENCE TABLE...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.FIRE WEATHER...
THERE IS LITTLE CHANGE IN THINKING FROM THE PREVIOUS FORECAST CYCLE.
THE PLANNING FORECAST HAS BEEN UPDATED THROUGH TOMORROW BASED UPON
THE LATEST FORECAST DATA...PRIMARILY FOR MINOR CHANGES IN SMOKE
MANAGEMENT PARAMETERS. RH HAS ALSO BEEN LOWERED SLIGHTLY FOR THIS
AFTERNOON...BUT MIN RH OF 25 PERCENT OR LESS IS EXPECTED TO BE
LOCALIZED AND BRIEF...WHILE WINDS SHOULD GRADUALLY DIMINISH THROUGH
THE AFTERNOON.
AS THE AIR MASS BEGINS TO WARM ON THURSDAY...RH IS EXPECTED TO FALL
BELOW 20 PERCENT IN MOST AREAS DURING THE AFTERNOON. IN ADDITION...
W/NW WINDS WILL BEGIN TO INCREASE AHEAD OF ANOTHER DRY COLD FRONT
DURING THE AFTERNOON. WINDS MAY GUST AS HIGH AS 30 MPH IN THE
MTNS...AND TO AROUND 20 MPH IN THE PIEDMONT. CRITICAL WIND AND RH
MAY OVERLAP FOR SEVERAL HOURS ACROSS THE MTNS AND NC FOOTHILLS THU
AFTERNOON.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...CDG/WIMBERLEY
SHORT TERM...MCAVOY
LONG TERM...JPT
AVIATION...CDG
FIRE WEATHER...LANE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
314 PM CST WED FEB 26 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 314 PM CST WED FEB 26 2014
THE MAIN FOCUS FOR TONIGHT INTO TOMORROW IS WITH THE BLOWING SNOW
TONIGHT FOLLOWED BY COLD WIND CHILLS TOMORROW MORNING.
CURRENTLY...GUSTY SOUTHWEST WINDS ARE OCCURRING THROUGH MUCH OF
THE REGION AS A SURFACE LOW PROPAGATES EAST ACROSS THE UPPER GREAT
LAKES. THE STRONGEST WINDS HAVE BEEN ACROSS THE TYPICAL AREAS IN
SOUTHEAST MINNESOTA AND NORTHEAST IOWA WHERE SOME BLOWING AND
DRIFTING SNOW HAS ALREADY REDUCED VISIBILITIES INTO THE 1 TO 2SM
RANGE. AS THE MAIN MID LEVEL CLOSED LOW DROPS TO THE SOUTHEAST
ACROSS ONTARIO AND A COLD FRONT MOVES THROUGH THE REGION
TONIGHT...THE GRADIENT WILL TIGHTEN UP AS COLDER AIR GETS ADVECTED
IN FROM THE NORTHWEST WITH SOME LIGHT SNOW ALSO OCCURRING.
UPSTREAM OBSERVATIONS AND FORECAST SOUNDINGS FROM THE 26.12Z
NAM/GFS AND THE 26.18Z RAP SUGGEST THAT WINDS WILL COME AROUND TO
THE NORTHWEST AFTER THE FROPA AND QUICKLY INCREASE WITH SUSTAINED
WINDS IN THE 20 TO 30 MPH RANGE AND GUSTS AROUND 40 MPH FOR THIS
EVENING. THIS WILL LEAD TO MORE WIDESPREAD BLOWING AND DRIFTING
SNOW...PARTICULARLY IN SOUTHEAST MINNESOTA...NORTHEAST IOWA AND
NORTH CENTRAL WISCONSIN WHERE THE WINDS WILL BE THE HIGHEST AND
THE SNOW PACK IS THE EASIEST TO BE PUSHED AROUND.
BECAUSE OF THIS...THE MAIN CONCERN WAS WITH WHETHER THE ADVISORY
NEEDED TO BE UPGRADED TO A BLIZZARD WARNING AND ALSO WHETHER THE
ADVISORY NEEDED TO BE EXPANDED EAST AT ALL. CONFIDENCE IS NOT HIGH
ENOUGH TO GO THE BLIZZARD ROUTE AT THIS POINT BECAUSE THERE HAS
NOT BEEN A RECENT ACCUMULATING SNOW TO BLOW AROUND OVER THE TOP OF
THE OLDER SNOW PACK. SO...WHILE SNOW WILL BLOW AND CAUSE SOME
REDUCED VISIBILITIES AND SNOW COVERED ROADS...CONFIDENCE IS NOT
HIGH ENOUGH TO THINK THAT THERE WILL BE WIDESPREAD ROAD CLOSURES
AND WHITEOUT CONDITIONS.
AS THE FRONT MOVES OFF TO THE EAST...THE COLDER AIR WILL COME INTO
THE REGION AND...WHEN COMBINED WITH THE STILL GUSTY WINDS...WILL
CAUSE WIND CHILLS TO DROP DOWN INTO THE 20 TO 35 DEGREES BELOW
ZERO RANGE LATE TONIGHT THROUGH TOMORROW MORNING. TOYED WITH THE
NEED FOR A WIND CHILL WARNING...BUT BASED ON THE FORECAST...WIND
CHILLS ONLY DROP TO 35 BELOW ACROSS PORTIONS OF SE MN/NE IA/NC WI
FOR A BRIEF PERIOD TOMORROW MORNING. THUS...WENT WITH AN ADVISORY
FROM 3AM THROUGH NOON TOMORROW.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 314 PM CST WED FEB 26 2014
THE MAIN FOCUS THROUGH THE EXTENDED PERIOD IS ON THE TWO MAIN
CHANCES FOR SNOW WHICH COME ON FRIDAY AND THEN ON
SATURDAY/SATURDAY NIGHT.
THE FRIDAY SYSTEM IS SHOWING GOOD CONTINUITY IN REGARD TO
TIMING...BUT HAS SOME DIFFERENCES IN STRENGTH BETWEEN THE 26.12Z
NAM/GFS/ECMWF. THIS SNOW IS STRICTLY COMING FROM TWO FORMS OF LOW
LEVEL FORCING...THE FIRST BEING 850MB WARM AIR ADVECTION AND THEN
A FRONTOGENETIC BAND THAT APPEARS TO BE THE STRONGEST AROUND
700MB. THE INITIAL WEST TO EAST BAND OF SNOW APPEARS TO DEVELOP
ALONG THE NOSE OF THE STRONGEST LOW LEVEL WARM AIR ADVECTION
FRIDAY MORNING/EARLY AFTERNOON WITH THE FRONTOGENESIS
STRENGTHENING ALONG A SOUTHWEST TO NORTHEAST BAND FRIDAY
AFTERNOON. THE HIGHER RESOLUTION 26.12Z NAM IS COMING IN WITH SOME
STRONGER LOW LEVEL LIFT AND IS PRODUCING SOME HIGHER PRECIPITATION
TOTALS WHILE THE 26.12Z GFS/ECMWF AS WEAKER AND HAVE ABOUT HALF OF
THE QPF THAT THE NAM HAS. WITH SNOW RATIOS LOOKING LIKE THEY WILL
BE AROUND 17:1...THE GOING FORECAST OF 1 TO 4 INCHES STILL LOOKS
GOOD...BUT TRENDS WILL HAVE TO BE WATCHED FOR WHETHER THIS
FRONTOGENESIS ENDS UP BEING STRONG ENOUGH TO PRODUCE SOME LOCALLY
HIGHER AMOUNTS. THE 26.15Z SREF PLUMES SHOW THAT MOST OF THE
MEMBERS...INCLUDING THE MEAN...ARE IN THE 1 TO 4 INCH RANGE...BUT
THERE ARE SOME MEMBERS THAT ARE PUSHING THAT 6 INCH THRESHOLD.
THE NEXT ROUND OF SNOW WILL COME ON SATURDAY AND SATURDAY NIGHT
THANKS TO SOME BROAD MID LEVEL TROUGHING DIGGING DOWN INTO THE
UPPER MISSISSIPPI RIVER VALLEY AND A TIGHTENING LOW TO MID LEVEL
TEMPERATURE GRADIENT THAT LEADS TO SOME WEAK TO MODERATE
FRONTOGENESIS. STILL SOME DIFFERING OPINIONS BETWEEN THE 26.12Z
GFS/ECMWF/GEM WITH WHERE THIS SNOW ENDS UP TRACKING...BUT THE
HIGHEST PROBABILITIES LIE ACROSS NORTHEAST IOWA INTO FAR SOUTHWEST
WISCONSIN.
BEYOND THIS...THE COLD CONTINUES THROUGH THE EARLY PART OF NEXT
WEEK WITH SOME POSSIBLE LOW LEVEL WARMING COMING ON WEDNESDAY.
THE 26.12Z ECMWF SUGGESTS THAT A SYSTEM COULD COME THROUGH ON
TUESDAY/WEDNESDAY AND BRING SOME LIGHT SNOW ACROSS SOUTHEAST
MINNESOTA AND WESTERN WISCONSIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1143 AM CST WED FEB 26 2014
MAIN AVIATION FORECAST CONCERNS THROUGH THE PERIOD ARE THE
INCREASING WINDS AT BOTH RST AND LSE TAF SITES THIS AFTERNOON INTO
TONIGHT. LATEST SURFACE PLOT SHOWS PRESSURE GRADIENT TIGHTENING
ACROSS MUCH OF THE AREA OUT AHEAD OF A COLD FRONT OVER EXTREME
NORTHWEST MINNESOTA AND CENTRAL NORTH DAKOTA. WINDS THIS AFTERNOON
WILL CONTINUE TO INCREASE FROM THE SOUTHWEST AT BOTH TAF
SITES...WITH SUSTAINED WINDS OF 15 TO 20 KNOTS AND GUSTS OF 25 UP
TO 30 KNOTS. THIS WILL CAUSE SOME DRIFTING OR BLOWING SNOW AT RST
BY 21Z WEDNESDAY AND POSSIBLY REDUCTION IN VISIBILITY BELOW 5
MILES. A COLD FRONT IS EXPECTED TO MOVE ACROSS AROUND 00Z
THURSDAY AT BOTH TAF SITES AND CHANGE WIND DIRECTION TO THE
NORTHWEST. THE STRONG WINDS WILL CONTINUE INTO TONIGHT...AS THE
PRESSURE GRADIENT REMAINS TIGHT BEHIND THE FRONT. WINDS COULD GUST
AS HIGH AS 40 KNOTS AT RST AND UP TO 35 KNOTS AT LSE THIS EVENING.
THE BLOWING AND DRIFTING SNOW COULD REDUCE VISIBILITY DOWN BELOW
THREE MILES AT TIMES AT RST BETWEEN 00-05Z THURSDAY. FOR NOW HAVE
INTRODUCED MARGINAL MVFR VISIBILITY RESTRICTION AT RST THIS
EVENING. WITH THE COLD FRONT PASSAGE...THE LATEST 26.12Z MODELS
ARE HINTING OF A FEW HOURS OF MVFR CEILING CONDITIONS AT BOTH RST
AND LSE THIS EVENING. HAVE LEFT THIS MVFR CEILING CONDITION AT
BOTH TAF SITES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL 3 AM CST THURSDAY FOR WIZ017-029.
WIND CHILL ADVISORY FROM 3 AM TO NOON CST THURSDAY FOR WIZ017-
029-032>034-041>044-053>055-061.
MN...WINTER WEATHER ADVISORY UNTIL 3 AM CST THURSDAY FOR MNZ079-086-
087-094-095.
WIND CHILL ADVISORY FROM 3 AM TO NOON CST THURSDAY FOR MNZ079-
086>088-094>096.
IA...WINTER WEATHER ADVISORY UNTIL 3 AM CST THURSDAY FOR IAZ008>010-
018-019-029.
WIND CHILL ADVISORY FROM 3 AM TO NOON CST THURSDAY FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...DTJ
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
242 PM CST WED FEB 26 2014
.TONIGHT AND THURSDAY - CONFIDENCE...MEDIUM
MAIN FOCUS ON THE BITTER COLD. EVENING FORECAST ISSUE WILL BE SHSN
DEVELOPMENT. SHORTWAVE ENERGY SHIFTS FROM NRN WI TO THE EASTERN LAKES.
LOW LEVEL FRONTOGENETICAL FORCING WITH RENEWED ARCTIC SURGE ALONG WITH
STEEP LOW LEVEL LAPSE RATES...SHOULD BE ENOUGH TO GENERATE A FEW-SCT
SHSN. NAM HI-RES AND HRRR BOTH AND 4KM SPC WRF ALL SHOW THIS DEVELOPMENT
THIS EVENING WITH ANY LINGERING PRECIP WRAPPING UP AROUND 6Z. ONLY A
FEW TENTHS OR SO AND SOME BLOWING TO GO ALONG WITH IT. STRONG COLD
ADVECTION SURGE AFTER 6Z CONTINUES INTO MIDDAY WITH 925 TEMPS
BOTTOMING OUT AROUND -22 TO -25C BETWEEN 12 AND 18Z. WITH AIRMASS
WELL MIXED TEMPS WILL NOT BOTTOM OUT TO THAT POTENTIAL BUT TEMPS
WILL DROP BY PURE ADVECTION. THIS IN CONCERT WITH TIGHT PRESSURE
GRADIENT WILL ALLOW WIND CHILL ADVISORY CRITERIA TO BE MET ONCE
AGAIN...SO HAVE HOISTED ONE FROM 09-18Z.
.THURSDAY NIGHT...FORECAST CONFIDENCE IS HIGH.
HIGH PRESSURE WILL SLIDE ACROSS THE AREA...WITH THE CENTER OF THE
HIGH PASSING OVER THE DUBUQUE AREA EARLY IN THE EVENING. BY 6AM
FRIDAY MORNING THE HIGH IS OVER ERN OH/WRN PA WITH THE LOW LEVEL
FLOW STARTING TO PICK UP ACROSS THE FORECAST AREA. THIS HAS BEEN
A TRICKY PERIOD WITH RESPECT TO LOW TEMPS DUE TO THE POTENTIAL FOR
STRONG RADIATIONAL COOLING. THE GFS HAS BEEN THE MOST AGGRESSIVE
OVER THE LAST FEW DAYS AND CONTINUES TO BE THE EXTREME.
WARM ADVECTION HEADING TOWARD THE AREA WILL CAUSE HIGH CLOUDS TO
SPREAD IN FROM THE WEST AFTER MIDNIGHT. JUST HOW COLD WE CAN GET
BEFORE THAT BLANKET ARRIVES IS THE BIGGEST QUESTION. THE GUIDANCE
IS NOW SUGGESTING THE COLDEST READINGS WILL BE ALONG AND JUST WEST
OF THE KETTLE MORAINE SPINE IN SOUTHEAST WISCONSIN. THE HILLS OUT
WEST OF MADISON MAY NOT TANK TOO LOW DUE TO THE EXPECTED CLOUDS
AND BREEZE KICKING IN. IN GENERAL...HAVE BACKED OFF A BIT ON WHAT
WE HAD GOING...BUT STILL WELL BELOW ZERO MOST PLACES. FAVORED
COLD SPOTS IN LOW AREAS COULD GET SURPRISINGLY COLD.
.FRIDAY AND FRIDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM.
THE WARM ADVECTION MENTIONED ABOVE WILL ARRIVE AHEAD OF AN
INVERTED TROF THAT WILL ENTER WESTERN WISCONSIN FRIDAY AFTERNOON.
SNOW SHOULD BEGIN TO SPREAD INTO THE WEST TOWARD LATE MORNING AND
THE REST OF THE FORECAST AREA DURING THE DAY AND CONTINUE THROUGH
THE EVENING BEFORE EXITING TO THE EAST AFTER MIDNIGHT. WE COULD
SEE 2 TO 3 INCHES OF DRY SNOW WITH THIS.
.SATURDAY INTO SUNDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM.
THE OVERALL FLOW WILL HAVE BECOME ZONAL BY SATURDAY WITH A FEW
RIPPLES MOVING THROUGH THE AREA...MAINLY AFFECTING FAR SOUTHERN
WISCONSIN. TEMPERATURES WILL ALSO MODIFY...OR WARM...FROM THEIR
DEEP CHILL...BUT STILL REMAIN BELOW NORMAL. AT THE SURFACE HIGH
PRESSURE WILL STRETCH FROM THE NORTHERN PLAINS INTO THE GREAT
LAKES. THE WEAK MID LEVEL SHORT WAVES MOVING THROUGH WILL ONLY
BRING CHANCES OF SOME FAIRLY LIGHT SNOW. NOTHING MAJOR...BUT WE/LL
HAVE A CHANCE FOR SNOW MAINLY FROM SATURDAY AFTERNOON INTO
SUNDAY...TAPERING OFF OR ENDING BY SUNDAY NIGHT.
.MONDAY AND MONDAY...FORECAST CONFIDENCE IS MEDIUM.
THE HIGH OVER THE PLAINS IS EXPECTED TO DRIFT INTO THE AREA...BUT
THE GFS AND ECMWF DIFFER ON THE SPEED/STRENGTH/PLACEMENT OF THAT
HIGH BY MONDAY NIGHT. EITHER WAY...IT LOOKS DRY.
&&
.AVIATION/00Z TAFS/...HRRR/NAM HI-RES AND OTHER SYNOPTIC MODELS
SHOWING RELATIVELY SMALL WINDOW OF SHSN POTENTIAL THIS EVENING. THIS
ASSOCIATED WITH NEXT ARCTIC BOUNDARY AND POTENT SHORTWAVE MOVING
FROM NRN WI INTO LOWER MI. VFR CONDITIONS WILL BE PREVALENT MOST OF
THIS PERIOD BUT EXPECT LOCALIZED VSBYS/CIGS TO DROP TO MAINLY MVFR
WITH ANY SHSN THAT DEVELOP OR ADVECT IN. THIS WOULD MOSTLY BE IN THE
01Z-06Z TIME FRAME.
&&
.MARINE...DECIDED TO HOIST A GALE WARNING FOR MIDNIGHT THROUGH NOON.
SEEING PRETTY DECENT SIGNALS ON BUFKIT FOR A PERIOD OF GALES IN THE
WAKE OF THE LATEST ARCTIC FRONT COMING THROUGH THIS EVENING. THE GOING
SMALL CRAFT WILL LEAD UP TO THE GALE WARNING AND THEN WILL LIKELY BE
NEEDED FOR A WHILE AT THE CONCLUSION OF THE GALE WARNING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WIND CHILL ADVISORY FROM 3 AM TO NOON CST THURSDAY FOR WIZ046-
047-051-052-056>060-062>072.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM CST THURSDAY FOR LMZ643>646.
&&
$$
TONIGHT/THURSDAY AND AVIATION/MARINE...COLLAR
THURSDAY NIGHT THROUGH WEDNESDAY...DAVIS