Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/05/16
AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NWS LITTLE ROCK AR
1055 PM CST WED MAR 2 2016
.AVIATION... CLOUDS WILL THICKEN OVERNIGHT...WITH WIDESPREAD
MVFR/SOME IFR CONDITIONS LATE TONIGHT/THURSDAY MORNING. SHOWERS
WILL BECOME WIDESPREAD...WITH ISOLATED THUNDERSTORMS.
PRECIPITATION WILL END BY THE EARLY AFTERNOON THURSDAY.
CLOUDS WILL DECREASE...WITH VFR CONDITIONS RETURNING.
WINDS TONIGHT WILL BE SOUTHEAST AT 8 TO 14 MPH...AND WILL
SHIFT TO THE NORTHWEST AT 10 TO 18 MPH THURSDAY. (46)
&&
.SHORT TERM...TONIGHT THRU THURSDAY NIGHT...
NWLY FLOW ALOFT CONTINUING THIS EVENING IN ADVANCE OF NEXT SYSTEM
WHICH WILL BE MOVING DOWN AND DEVELOPING RATHER QUICKLY FROM THE NW.
THIS WILL BEGIN AFFECTING THE WEATHER ACROSS THE AREA TONIGHT AND
CONTINUING THROUGH TOMORROW. ASSOCIATED COLD FRONT WILL BE MOVING
THROUGH THE STATE TOMORROW...ALTHOUGH THERE WILL NOT BE TOO
SUBSTANTIAL OF A COOL DOWN WITH THIS AIR MASS...BASICALLY 5 TO 10
DEGREES AT BEST.
LARGE SCALE ASCENT AHEAD OF THE LOW AND SFC BASED LIFT WITH THE
FRONT SHOULD TRANSLATE INTO GREATER POPS THAN IS PRESENT IN THE
EXISTING FORECAST. SHORTER TERM HRRR AND THE NAM ARE IN GOOD
AGREEMENT WITH THIS SCENARIO. THIS WOULD RESULT IN PRECIP IN GREATER
COVERAGE THAN IS COVERED IN THE EXISTING FORECAST...SO I AM
BOOSTING POPS UP QUITE A BIT OVER THE EXISTING FORECAST.
ONLY LIMITING FACTOR WILL BE LOW LEVEL MOISTURE AVAILABILITY...WITH
LIMITED MOISTURE FROM THE SFC THROUGH THE MID LEVELS. FOR THIS
REASON I SCALED BACK MODEL BASED QPF VALUES SOMEWHAT.
AS FOR THUNDERSTORM CHANCES OVERNIGHT INTO TOMORROW...THE DYNAMICS
OF THE APPROACHING SYSTEM LOOK GOOD. RATHER STEEP MID LEVEL LAPSE
RATES WILL BE IN PLACE...WITH QUITE A BIT OF UPPER LEVEL DIFLUENCE
ASSOCIATED WITH A RATHER STRONG JET. ON THE DOWNSIDE THE OVERALL
PARCEL INSTABILITY IS WEAK...AND THE AFOREMENTIONED MOISTURE
LIMITATIONS WILL BE A FACTOR.
FOR NOW I AM WORDING THE WEATHER GRIDS AS SHOWERS WITH THE
POSSIBILITY OF ISOLATED THUNDERSTORMS. HOWEVER IF OVERNIGHT TRENDS
START TO SHOW MORE LIGHTNING...THIS MAY NEED TO BE ADJUSTED TO FAVOR
THUNDERSTORMS MORE PROMINENTLY.
&&
.LONG TERM...THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL PATTERN WILL REMAIN ACTIVE DURING THE LONG TERM
FORECAST PERIOD...WITH THE POSSIBILITY OF A SIGNIFICANT ROUND OF
THUNDERSTORMS ON TUESDAY NEXT WEEK.
HIGH PRESSURE WILL BE SITUATED OVER THE STATE ON FRIDAY BUT WILL
PUSH OFF TO THE EAST AS ANOTHER FRONT MOVES INTO THE REGION
SATURDAY. THIS FRONT WILL BE A DRY FRONT BUT IT WILL STALL OUT AND
BE A FOCUS FOR PRECIPITATION DEVELOPMENT ON SUNDAY AS IT LIFTS BACK
NORTH THROUGH THE STATE AS A WARM FRONT.
STARTING SUNDAY...SEVERAL IMPULSES WILL LIFT NORTHEAST THROUGH THE
ARKLATEX REGION AS A VERY DEEP TROUGH SETS UP SHOP ACROSS THE
WESTERN CONUS. EACH OF THESE IMPULSES WILL BRING SHOWERS AND
THUNDERSTORMS TO THE STATE...MAINLY TO WESTERN ARKANSAS SUNDAY AND
MONDAY. THE FIRST WILL MOVE THROUGH SUNDAY NIGHT...FOLLOWED BY
ANOTHER MONDAY EVENING...AND FINALLY A STRONGER ONE ON TUESDAY.
MOISTURE RETURN WILL INCREASE WITH TIME AS THE GULF OF MEXICO OPENS
UP...WITH MODELS FORECASTING DEWPOINTS 60-65F ACROSS MUCH OF THE
STATE MONDAY NIGHT INTO TUESDAY. MODELS HAVE BEEN FAIRLY CONSISTENT
IN SHOWING SIGNIFICANT PRECIPITATION AND THE CHANCE FOR STRONG TO
SEVERE THUNDERSTORMS ACROSS THE REGION ON TUESDAY. IT IS STILL THE
DAY 7 FORECAST PERIOD WHICH IS TO SAY THERE IS A LOT OF TIME FOR
THIS TO CHANGE. BUT WILL NEED TO MONITOR THIS SITUATION AS SEVERE
STORMS COULD BE A DISTINCT POSSIBILITY.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 45 61 38 58 / 70 50 0 0
CAMDEN AR 52 71 41 67 / 50 50 0 0
HARRISON AR 43 58 34 61 / 50 30 0 0
HOT SPRINGS AR 48 67 40 64 / 70 30 0 0
LITTLE ROCK AR 47 65 40 62 / 70 40 0 0
MONTICELLO AR 51 67 42 62 / 60 70 0 0
MOUNT IDA AR 48 66 38 65 / 60 30 0 0
MOUNTAIN HOME AR 45 59 35 60 / 60 30 0 0
NEWPORT AR 43 61 38 56 / 60 70 10 0
PINE BLUFF AR 46 64 40 61 / 50 40 0 0
RUSSELLVILLE AR 46 65 37 63 / 80 30 0 0
SEARCY AR 45 62 38 59 / 70 70 0 0
STUTTGART AR 46 63 39 59 / 60 60 0 0
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...53 / LONG TERM...64
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
904 AM MST THU MAR 3 2016
.SYNOPSIS...
A VERY STRONG HIGH PRESSURE SYSTEM WILL CONTINUE TO PRODUCE VERY
WARM NEAR RECORD TEMPERATURES ACROSS THE REGION THROUGH SATURDAY.
HOWEVER...LOW PRESSURE MOVING INLAND FROM THE EASTERN PACIFIC WILL
FINALLY BRING MUCH COOLER TEMPERATURES WITH A GOOD CHANCE FOR RAIN
AND MOUNTAIN SNOW FROM SUNDAY ONWARD INTO EARLY NEXT WEEK. DRIER AND
WARMER WEATHER WILL THEN RETURN DURING THE MIDDLE PART OF NEXT WEEK
AS HIGH PRESSURE REBUILDS INTO THE DESERT SOUTHWEST.
&&
.DISCUSSION...
LATEST SATELLITE IMAGERY AND STREAMLINE ANALYSIS SHOWS A DIRTY RIDGE
IN PLACE WITH CIRRUS IN THE PACIFIC SPILLING OVER INTO THE DESERT
SOUTHWEST. 12Z SOUNDING FROM KTWC SHOWS WARM TEMPERATURES AT 850 MB
AROUND THE 90TH PERCENTILE. HOWEVER...MEDIAN OF MORNING MULTI-MODEL
ENSEMBLE INCLUDING THE HRRR SUGGESTS AFTERNOON TEMPERATURES MAY NOT
REACH THEIR FULL POTENTIAL...DUE TO THE DECREASED INSOLATION.
FORECAST HIGH TEMPERATURES WILL BE LOWERED ROUGHLY ONE DEGREE THIS
MORNING. NEVERTHELESS...HIGH TEMPERATURES WILL BE WITHIN A FEW
DEGREES OF THE RECORD IN PHOENIX BUT SEVERAL DEGREES SHORT IN YUMA.
&&
.PREVIOUS DISCUSSION...
TODAY THROUGH SATURDAY... VERY WARM WEATHER
IS STILL EXPECTED TO PREVAIL DURING THIS PERIOD AS STRONG HIGH
PRESSURE ALOFT MOVES SLOWLY EASTWARD ACROSS THE REGION. 500MB HEIGHTS
ARE STILL FORECAST O REMAIN IN THE 576-582DM RANGE THROUGH
FRIDAY...AOA THE 95TH PERCENTILE...THEN LOWER A BIT ON SATURDAY AS
THE 1ST IN THE SERIES OF STRONG SHORTWAVES BEGINS TO MOVE INLAND
ACROSS CENTRAL AND NORTHERN CA. THE COMBINATION OF THESE VERY HIGH
HEIGHTS AND 850 MB TEMPS IN THE 17-20C RANGE WILL ONCE AGAIN ALLOW
LOWER DESERT HIGHS TO RISE INTO THE UPPER 80-LOW 90 RANGE TODAY AND
FRIDAY...THEN FALL A BIT...INTO THE MID-UPPER 80S ON
SATURDAY...THREATENING...OR EVEN BREAKING DAILY RECORDS.
SUNDAY THROUGH TUESDAY...
A SIGNIFICANT CHANGE IN THE WEATHER NOW SEEMS ALMOST CERTAIN FOR
THIS PERIOD...AS THERE IS NOW GOOD-EXCELLENT MODEL AGREEMENT THAT
TWO MAJOR SHORTWAVES WILL BE MOVING INTO THE REGION. THE 1ST
ONE...WHICH IS EXPECTED TO MOVE INTO THE REGION ON SUNDAY...IS THE
WEAKER OF THE TWO. THE MAIN IMPACT FROM THIS SHORTWAVE WILL BE TO
FINALLY PUSH THE STRONG HIGH PRESSURE RIDGING THAT IS NOW BRINGING
US VERY WARM WEATHER WELL OFF TO OUR EAST. ALTHOUGH MOST OF THE
DYNAMICS...AND AVAILABLE MOISTURE ASSOCIATED WITH THIS SHORTWAVE IS
EXPECTED TO REMAIN TO OUR NORTH...ALL OF THE 3 MAIN GLOBAL MODELS DO
PUSH ENOUGH MOISTURE INTO THE NORTHERNMOST PORTIONS OF OUR CWA TO
PRODUCE AT LEAST A SLIGHT CHANCE OF SHOWERS IN THOSE AREAS. THE MAIN
IMPACTS FOR MOST OF OUR CWA WILL BE TO COOL TEMPERATURES DOWN INTO
THE UPPER 70-LOW 80 RANGE ACROSS THE LOWER DESERTS AND TO BRING
GUSTY WESTERLY WINDS TO MOST LOCATIONS ON SUNDAY AFTERNOON...WITH
SUSTAINED WIND SPEEDS RISING INTO THE 25-35 MPH RANGE...WITH AREAS
OF BLOWING DUST POSSIBLE...AS A 80 KT WESTERLY JET AT 300MB MOVES
INTO THE REGION.
A SECOND...STRONG SHORTWAVE/UPPER LOW IS THEN FORECAST TO MOVE INTO
OUR CWA DURING THE MONDAY AFTERNOON-TUESDAY PERIOD. THERE IS A
RATHER TIGHT SPREAD (FOR THIS FAR OUT) BETWEEN THE VARIOUS GLOBAL
MODELS...AND THE MAJORITY OF THEIR RESPECTIVE ENSEMBLE MEMBERS ON
THE TRACK AND INTENSITY OF THIS SHORTWAVE/UPPER LOW. THE MODEL
CONSENSUS IS TO MOVE THE UPPER LOW CENTER SE-WARD ACROSS CA ON
MONDAY AND MONDAY NIGHT...THEN INTO NORTHERN SONORA MEXICO ON
TUESDAY. ALTHOUGH THIS TRACK WILL BRING SOME IMPRESSIVE
DIFLUENCE/HEIGHT FALLS/COOLING ALOFT TO OUR CWA...WITH 500MB
TEMPERATURES FALLING AS LOW AS -26C...MOISTURE NOW APPEARS IT WILL
BE A BIT LIMITED...WITH PWATS ONLY RISING INTO THE 0.6-0.8 INCH
RANGE AS THE ATMOSPHERIC RIVER ASSOCIATED WITH THIS SYSTEM BECOMES
PINCHED OFF AS IT MOVES DOWN THE CA COAST...WITH MOST PLACES SEEING
1/3 INCH OF RAIN...OR LESS. STILL...LOCALLY HEAVIER RAINFALL AMOUNTS
CAN BE EXPECTED AS THE STRONG DYNAMICS/COOLING ALOFT TRIGGER SOME
HEAVIER SHOWERS/THUNDERSTORMS. RAINFALL AMOUNTS COULD BE LIMITED
FURTHER IF THE UPPER LOW LOW TRACKS FURTHER TO THE SOUTH...WHICH
MANY OF THE OUTLYING ENSEMBLE MEMBERS ARE SUGGESTING AT THIS TIME.
AS FAR AS SNOWFALL IS CONCERNED...IT APPEARS THAT ACCUMULATING SNOWS
WILL BE CONFINED TO THE HIGHEST PEAKS OF OUR CWA...WHERE A COUPLE OF
INCHES MAY FALL LATE MONDAY NIGHT/EARLY TUESDAY. ALONG WITH THE
PRECIP CHANCES...MUCH COOLER TEMPERATURES ARE EXPECTED...WITH LOWER
DESERT HIGHS REMAINING IN THE UPPER 60-MID 70 RANGE.
WEDNESDAY THROUGH THURSDAY.
A DRYING AND WARMING TREND IS EXPECTED DURING THIS PERIOD AS HIGH
PRESSURE BUILDS BACK OVER THE REGION BEHIND THE UPPER TROF...WITH
HIGHS LIKELY TO REBOUND UP INTO THE UPPER 70-LOW 80 RANGE BY
THURSDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
VERY MUCH A PERSISTENCE FORECAST FOR THE NEXT 24 HOURS AS STRONG
HIGH PRESSURE ALOFT CONTINUES TO DOMINATE THE WEATHER PATTERN OVER
THE DESERT SOUTHWEST. EXPECT MAINLY THIN BROKEN CIRRUS DECKS THROUGH
THIS EVENING AT THE TAF SITES WITH SOME THINNING OF THE CLOUDS FROM
THE WEST OVERNIGHT TONIGHT. LIGHT GRADIENTS PERSIST AND WE CAN
EXPECT MOSTLY LIGHT WINDS FAVORING NORMAL DIURNAL TENDENCIES...
ESPECIALLY IN THE GREATER PHOENIX AREA...NEXT 24 HOURS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER... SATURDAY THROUGH WEDNESDAY...OVER THE WEEKEND THE
HIGH PRESSURE SYSTEM THAT HAS PROVIDED NEAR RECORD HIGH TEMPERATURES
EARLIER THIS WEEK WILL BREAK DOWN AS A STRONG PACIFIC LOW PRESSURE
SYSTEM MOVES INTO THE WEST COAST. A COOLING TREND WILL DEVELOP AND A
SHARP INCREASE IN WIND IS EXPECTED AS THE FIRST IN A SERIES OF
DISTURBANCES MOVES ACROSS THE AREA LEADING TO A SLIGHT CHANCE OF
SHOWERS AREA WIDE ON SUNDAY. STRONG GUSTY SOUTHWEST WINDS WILL
DEVELOP DURING THE DAY SUNDAY WITH AFTERNOON GUSTS IN EXCESS OF 30
MPH OVER MUCH OF THE WESTERN DESERTS. MINIMUM HUMIDITY LEVELS
INCREASE FROM THE WEST OVER THE WEEKEND WITH MOST LOWER DESERTS
RISING INTO THE 15 TO 20 PERCENT BALLPARK ON SUNDAY.
FOR MONDAY INTO TUESDAY...THERE WILL BE A SIGNIFICANT INCREASE IN
HUMIDITY AS A STRONGER LOW PRESSURE SYSTEM MOVES ACROSS THE AREA
BRINGING A GOOD CHANCE OF SHOWERS ALONG WITH POTENTIAL FOR WETTING
RAINS. GUSTY WEST TO NORTHWEST WINDS WILL CONTINUE BOTH DAYS
ESPECIALLY OVER THE WESTERN ARIZONA AND SOUTHEAST CALIFORNIA DESERT.
THE INCREASE IN WIND SUNDAY INTO EARLY NEXT WEEK WILL BE OFFSET BY
THE INCREASING SURFACE HUMIDITY AND THIS WILL LIMIT THE CHANCES THAT
CRITICAL FIRE WEATHER THRESHOLDS WILL BE MET. OF COURSE...MUCH
COOLER TEMPERATURES WILL ACCOMPANY THE PASSAGE OF THE DISTURBANCE
WITH HIGHS FALLING BELOW SEASONAL NORMALS MONDAY OVER THE
DESERTS...WITH SOME WARMING EXPECTED OVER THE WESTERN DESERTS
TUESDAY.
ON WEDNESDAY...DRIER AND WARMER CONDITIONS ARE EXPECTED ALONG WITH
MUCH LESS WIND AS HIGH PRESSURE BUILDS INTO THE DESERTS FROM THE
WEST.
&&
.CLIMATE... PHOENIX | YUMA
FCST | RECORD /YEAR/ | FCST | RECORD /YEAR/
HIGH HIGH
THU MAR 3 90 | 91 /1921 | 91 | 95 /1910
FRI MAR 4 90 | 88 /1972 | 89 | 98 /1910
SAT MAR 5 87 | 93 /1972 | 88 | 97 /1910
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT BASED ON STANDARD OPERATING
PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...CB
FIRE WEATHER...CB
AREA FORECAST DISCUSSION
NWS TAUNTON MA
643 PM EST FRI MAR 4 2016
.SYNOPSIS...
STRONG OFFSHORE LOW PRESSURE WILL SKIRT SOUTHEAST NEW ENGLAND
TONIGHT WITH HIGH PRESSURE FILLING IN BEHIND THE LOW ON SATURDAY.
ALBERTA CLIPPER RACES SOUTH OF NEW ENGLAND SUNDAY. HIGH PRESSURE
THEN BUILDS MILDER WEATHER OVER OUR AREA THE FIRST HALF OF NEXT
WEEK. LOW PRESSURE RACES THROUGH EASTERN CANADA MIDWEEK AND PULLS
A COLD FRONT THROUGH NEW ENGLAND THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
630 PM UPDATE...
NO MAJOR CHANGES TO THE FORECAST AT THIS TIME. MAIN CHANGE WAS TO
ADJUST SKY COVER A LITTLE FARTHER WEST EARLY TONIGHT BUT
MAINTAINING THE CLEARING TREND OVERNIGHT.
SYSTEM SNOW IS OVER CAPE COD AND THE ISLANDS WITH NORTH-NORTHEAST
WINDS BRINGING OCEAN SNOW SHOWERS INTO THE NORTH SHORE AND INTO
EAST COASTAL PLYMOUTH COUNTY. THIS SHOULD CONTINUE FOR THE NEXT
COUPLE OF HOURS AND THEN SHOW A DIMINISHING TREND AFTER 9 PM.
WINDS NEAR THE COAST HAVE BEEN A LITTLE LOWER THAN FORECAST AND SO
WE WILL BRING WINDS/GUSTS DOWN A SMIDGE BUT MAINTAIN A WINDY NIGHT
ALONG THE COAST.
TEMPERATURES ARE WITHIN A DEGREE OR TWO OF FORECAST LEVELS AND SO
NO CHANGES AT THIS TIME.
PREVIOUS DISCUSSION...
STRONG OFFSHORE SYSTEM WILL CONTINUE TO DEEPEN THIS EVENING AS IT
MAKES ITS EASTWARD PROGRESSION SOUTH AND EAST OF THE 40N/70W
BENCHMARK. LATEST WATER VAPOR IMAGERY SHOWS CLASSIC LEAF PATTERN
WHEN THE LOW IS UNDERGOING CYCLOGENESIS. THIS RAMP-UP WILL
INCREASE THE PRESSURE GRADIENT ALLOWING 925 MB JET TO INCREASE
40-50 KTS.
ONE CONCERN FOR SNOW IS ACROSS THE MASS EAST COAST INCLUDING THE
NORTH SHORE. WENT AHEAD AN ISSUED A WINTER WEATHER ADVISORY FOR
ESSEX COUNTY. HI-RES GUIDANCE CONTINUES TO SHOW A NARROW BAND OF
HIGHER QPF LATER THIS AFTERNOON INTO THE EVENING HOURS. THIS IS IN
ASSOCIATION WITH THE RE-DEVELOPMENT OF OCEAN EFFECT SNOW MOVING
ONSHORE. THE LATEST NAM12 AS WELL AS THE HRRR ARE ALSO ON BOARD.
ONE INTERESTING NOTE IS THAT THE RAP GUIDANCE IS SHOWING
INSTABILITY OVER THE NORTH SHORE FOR MUCH OF THE AFTERNOON INTO
THE EVENING. THIS INSTABILITY COMBINED WITH THE DEVELOPMENT OF A
COASTAL FRONT WILL HELP ENHANCE THE OCEAN EFFECT SNOW SHOWERS MORE
SO THEN WHAT GUIDANCE IS INDICATING. COULD SEE ANOTHER 1-3 INCHES
FOR ESSEX COUNTY...WHICH WILL BE ON TOP OF THE 1-2 THAT PORTIONS
OF THAT AREA HAS ALREADY SEEN. ONCE THE SNOW SHOWERS
DEVELOP...BELIEVE THEY WILL MOVE SOUTHWARD THANKS TO THE NORTHERLY
DIRECTION OF THE WIND. SO LOCATIONS ALONG THE I-95 CORRIDOR AS
WELL AS ROUTE 3 IN PLYMOUTH COULD BE IMPACTED WITH A QUICK DUSTING
OF SNOW AS WELL AS REDUCED VSBYS...ESP DURING THE EVENING COMMUTE
AND INTO LATE EVENING HOURS. MOTORIST SHOULD USE CAUTION THIS
EVENING WHEN TRAVELING.
AS THE SYSTEM PULLS AWAY...A FEW LINGERING SNOW SHOWERS WILL
CONTINUE BEFORE ENDING AROUND 1-3 AM.
THE OTHER MAIN FOCUS IS THE STRONG TO DAMAGING WINDS. STRONGEST
WINDS WILL OCCUR AFTER MIDNIGHT INTO SATURDAY MORNING. AS LAPSE
RATES CONTINUE TO INCREASE ANTICIPATE LOCATIONS THE EASTERN HALF
OF SOUTHERN NEW ENGLAND TO SEE NEAR 25-35 MPH GUSTS. HOWEVER
STRONGEST GUSTS WILL OCCUR OVER THE CAPE AND THE ISLANDS...WHICH
IS CLOSER TO THE STRONG JET. THE WIND ADVISORY WILL CONTINUE AS
GUSTS BETWEEN 40- 50 MPH ARE POSSIBLE. THIS COULD BRING DOWN TREE
LIMBS AND WIRES.
THERE ARE A FEW COASTAL CONCERNS...PLEASE REACH THE COASTAL FLOODING
SECTION BELOW.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
SATURDAY...
SURFACE HIGH PRESSURE WILL FILL IN BEHIND DEPARTING OFFSHORE LOW FOR
SATURDAY. STRONG WINDS GUSTS OVER THE CAPE/ISLAND AND THE WATERS
WILL BEGIN TO SUBSIDE AS PRESSURE GRADIENT WEAKENS THROUGHOUT THE
DAY. UPPER LEVEL LOW TURNS A BIT MORE PROGRESSIVE WITH A SHORTWAVE
QUICKLY PASSING BY DURING THE DAY. THIS WAVE WILL RESULT IN AN
INCREASE IN MID AND HIGH LEVEL CLOUDS. DRY AIR IN THE LOW LEVELS
WILL KEEP SATURDAY DRY. TEMPERATURES WILL BE MORE SEASONABLE WITH
DAY TIME HIGHS IN THE LOW 40S TO UPPER 30S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
BIG PICTURE...
RIDGE-WEST/TROUGH-EAST PATTERN OVER THE WEEKEND FLATTENS EARLY NEXT
WEEK. CONTOUR HEIGHTS ARE FORECAST TO BUILD WEST TO EAST AS THE FLOW
FLATTENS. THIS SUGGESTS A WARMING TREND FOR MUCH OF NEXT WEEK.
SHORTWAVE SCALE SHOWS ONE SHORTWAVE MOVING THROUGH NEW ENGLAND
SUNDAY...EVENTUALLY FORMING A CLOSED LOW WELL OUT TO SEA. A SECOND
SHORTWAVE MOVES ALONG THE CANADIAN BORDER MONDAY. UPPER RIDGE THEN
BUILDS OVER THE EASTERN USA. A THIRD SHORTWAVE RACES ACROSS CANADA
THIS WEEK AND CROSSES NORTHERN NEW ENGLAND WEDNESDAY-THURSDAY...
FLATTENING THE NEW ENGLAND PORTION OF THE UPPER RIDGE.
THE DAILIES...
SATURDAY NIGHT-SUNDAY...
ALBERTA CLIPPER FROM THE GREAT LAKES MOVES TO THE MID ATLANTIC
COAST AND THEN SWINGS OFFSHORE AND WELL SOUTH OF NEW ENGLAND. THIS
WILL BE TOO FAR SOUTH TO DIRECTLY AFFECT OUR AREA. HOWEVER THE
SUPPORTING UPPER SHORTWAVE WILL MOVE OVER US. SUFFICIENT COLD AIR
AT THE CORE OF THE TROUGH TO INCREASE INSTABILITY...TOTALS ARE
FORECAST TO CLIMB INTO THE MID AND UPPER 40S WHICH SUGGESTS SOME
POTENTIAL FOR CONVECTION. LIKELY NOT ANY THUNDER...BUT A FEW SNOW
SHOWERS ARE POSSIBLE. THIS WILL THEN MOVE OFF WITH CLEARING FROM
WEST TO EAST SUNDAY AFTERNOON. MIXING WILL REACH TO 850 MB SUNDAY
WITH TEMPS AT THAT LEVEL SUPPORTING MAX SFC TEMPS IN THE LOWER
40S.
MONDAY THROUGH WEDNESDAY...
EXPECT A PERIOD OF QUIET WEATHER AS HIGH PRESSURE BUILDS TO OUR
SOUTH AT THE SURFACE AND ALOFT. A SHORTWAVE PASSING ACROSS QUEBEC
WILL PULL A WEAK WARM FRONT THROUGH NEW ENGLAND ON MONDAY...BUT MOST
OF THE DYNAMIC SUPPORT WILL BE ALONG THE CANADIAN BORDER. SO WE MAY
SEE MID AND HIGH CLOUDS BUT NO PCPN. PRESSURE GRADIENT WILL TIGHTEN
BEHIND THE WARM FRONT WITH SUPPORT FOR WINDS GUSTING 20-25 KNOTS
ALONG THE COASTAL PLAIN.
THE MAIN EVENT FOR THE EARLY WEEK WILL BE THE WARMING TEMPS. WARM
ADVECTION ALOFT WILL SHRINK THE DEPTH OF THE MIXED LAYER...BUT
MIXING EVEN TO 925 MB WOULD SUPPORT MID 60S TUESDAY AND UPPER
60S/LOWER 70S WEDNESDAY. THIS IS A LITTLE HIGHER THAN GUIDANCE...SO
WE BUMPED GUIDANCE VALUES UP 2-3 DEGREES.
THURSDAY-FRIDAY...
ANOTHER SHORTWAVE CROSSING EASTERN CANADA WILL PUSH A COLD FRONT
SOUTH THROUGH NEW ENGLAND. THIS FRONT SHOULD CROSS OUR AREA EITHER
WEDNESDAY NIGHT PER THE GFS OR THURSDAY MIDDAY-AFTERNOON PER THE
ECMWF. THIS COLD FRONT MAY BRING A CHANCE OF SHOWERS. HIGH PRESSURE
THEN BUILDS DRIER COOLER WEATHER FOR FRIDAY. CONFIDENCE IS LIMITED
BY THE OBVIOUS TIMING UNCERTAINTY WITH THE COLD FRONT. BUT THE TREND
LOOKS FINE AT THIS TIME.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY/...
TONIGHT...HIGH CONFIDENCE.
VFR CIGS ACROSS THE CONNECTICUT VALLEY WITH MVFR CIGS FARTHER EAST
AND IFR ALONG THE EAST COAST AND CAPE/ISLANDS. EXPECT SNOW TO
CONTINUE EARLY TONIGHT AND THEN TAPER OFF 02-05Z. OCEAN EFFECT
SNOW SHOWERS AFFECTING THE NORTH SHORE AND PLYMOUTH COAST SHOULD
DIMINISH AS WINDS TURN NORTH.
EXPECT CLEARING SKIES WEST TO EAST AFTER MIDNIGHT. EXPECT 20-30 KT
WIND GUSTS AROUND I-95 WITH CAPE AND ISLANDS SEEING GUSTS NEAR
40-45 KTS BETWEEN 03-09Z.
SATURDAY...HIGH CONFIDENCE.
BRISK NW WINDS INTO THE MORNING FOR THE CAPE AND ISLANDS.
OTHERWISE LIGHT OVERALL AND VARIABLE AS HIGH PRESSURE BUILDS. VFR
WITH A BRIEF PERIOD OF SKC WITH INCREASING MID-HIGH CLOUDS IN THE
AFTERNOON.
KBOS TERMINAL...HIGH CONFIDENCE. IFR CONDITIONS EARLY TONIGHT.
SNOW SHOWERS AFFECTING THE NORTH SHORE WILL CONTINUE TO MOVE
SOUTHWEST THROUGH OR NEAR BOSTON THROUGH 03-04Z AND THEN DIMINISH.
LOWER CONFIDENCE ON EXACT VSBYS BUT ANTICIPATE OCCASIONAL
CONDITIONS AROUND 1SM. CONDITIONS IMPROVING TO VFR BY 07Z.
KBDL TERMINAL...HIGH CONFIDENCE. VFR CONDITIONS.
OUTLOOK /SATURDAY NIGHT THROUGH WEDNESDAY/...MODERATE CONFIDENCE.
VFR FOR MOST OF THE PERIOD. THERE IS A LOW-MODERATE CHANCE OF
MVFR/IFR CIGS/VSBYS IN SNOW SHOWERS SUNDAY ESPECIALLY ALONG THE
SOUTH COAST.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY/...
TONIGHT...
OFFSHORE COASTAL LOW DEEPENS RAPIDLY WHILE PASSING SE OF THE
40N/70W BENCHMARK. NE WINDS INCREASE WITH GUSTS UP TO 50 KTS
POSSIBLE DURING PASSAGE ESPECIALLY OVER THE SE WATERS. GALE AND
STORM FORCE WARNINGS ARE IN EFFECT. WAVES BUILDING UPWARDS OF
AROUND 15 FEET. SNOW/RAIN OUTCOMES ESPECIALLY S/SE WILL RESULT IN
VISIBILITY IMPACTS.
SATURDAY...
N/NW WINDS REMAINING BLUSTERY DURING THE FIRST HALF OF THE PERIOD
BEFORE DECREASING DURING THE DAY. COLDER AIR BUILDING S LENDS A
DEFINITE RISK OF FREEZING SPRAY AS WAVE HEIGHTS INITIALLY 10 TO 15
FEET GRADUALLY DIMINISH.
OUTLOOK /SATURDAY NIGHT THROUGH WEDNESDAY/...MODERATE CONFIDENCE...
SATURDAY NIGHT-SUNDAY...LOW PRESSURE PASSES WELL SOUTH OF THE
WATERS. HIGH PRESSURE BUILDS OVER THE WATERS. WINDS WILL REMAIN
LIGHT THROUGH SUNDAY. LINGERING 5 FOOT SEAS ON THE OUTER WATERS
SHOULD SUBSIDE. A SMALL CRAFT ADVISORY MAY BE NEEDED ON THOSE OUTER
WATERS SATURDAY NIGHT.
MONDAY THROUGH WEDNESDAY...
WEST TO SOUTHWEST FLOW THROUGH THE PERIOD WITH WINDS GUSTING NEAR 25
KNOTS MONDAY AFTER A WARM FRONT MOVES ACROSS THE WATER. SEAS REMAIN
LESS THAN 5 FEET THROUGH THE PERIOD...EXCEPT MAY BE AREAS AROUND 5
FEET ON THE OUTER WATERS WEDNESDAY. A SMALL CRAFT ADVISORY MAY BE
NEEDED MONDAY FOR THE WINDS AND ON THE OUTER WATERS WEDNESDAY FOR
THE SEAS.
&&
.TIDES/COASTAL FLOODING...
ONSHORE WIND AND SEAS INCREASE THIS EVENING BUT NOT ENOUGH TO HAVE
ANY SIGNIFICANT COASTAL IMPACT AROUND THE TIME OF THE EVENING HIGH
TIDE...WHICH IS PARTICULARLY LOW ASTRONOMICALLY. THE SATURDAY
MORNING HIGH TIDE IS HIGHER ASTRONOMICALLY BUT STILL NOT ALL THAT
HIGH AS ASTRONOMICAL TIDES GO. NEVERTHELESS...THERE WILL BE ENOUGH
SURGE AND RESIDUE SWELLS TO POSSIBLY CAUSE SOME EROSION ALONG THE
OUTER CAPE AND THE EAST SIDE OF NANTUCKET. ALTHOUGH DIMINISHING IN
SPEED...THERE WILL PROBABLY BE ENOUGH NORTHERLY FLOW TO KEEP A SURGE
NEAR OR SLIGHTLY ABOVE 1.5 FEET IN NANTUCKET HARBOR. THIS MAY BE
JUST ENOUGH TO CAUSE SOME VERY MINOR FLOODING OF THE MOST VULNERABLE
LOCATIONS SUCH AS EASY STREET. THE ESTOFS GUIDANCE LOOKED MORE
REASONABLE THAN THE ETSS THROUGH THIS EVENING GIVEN THE SYNOPTIC
PATTERN. HOWEVER...THE ETSS GUIDANCE LOOKED TO BE SUPERIOR FOR
OVERNIGHT AND SATURDAY. THE PRIOR SATURDAY MORNING SURGE FORECAST
STILL LOOKED GOOD FROM THIS SHIFT/S PERSPECTIVE WITH ONLY VERY MINOR
ADJUSTMENTS MADE ALONG PORTIONS OF THE CAPE COD NORTH AND EAST
FACING SHORELINES. WILL COVER THE POCKETS OF MINOR COASTAL FLOODING
AND EROSION DURING THE SATURDAY MORNING HIGH TIDE WITH A
STATEMENT.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MAZ006-
007.
WIND ADVISORY UNTIL 7 AM EST SATURDAY FOR MAZ022>024.
WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR MAZ024.
RI...NONE.
MARINE...GALE WARNING UNTIL 10 AM EST SATURDAY FOR ANZ231-232.
GALE WARNING UNTIL 7 AM EST SATURDAY FOR ANZ233>235-237-251.
GALE WARNING UNTIL 4 AM EST SATURDAY FOR ANZ230-236.
GALE WARNING UNTIL 1 PM EST SATURDAY FOR ANZ250-256.
STORM WARNING UNTIL 4 AM EST SATURDAY FOR ANZ254-255.
&&
$$
SYNOPSIS...WTB/DUNTEN
NEAR TERM...WTB/DUNTEN
SHORT TERM...DUNTEN
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/DUNTEN
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS ALBANY NY
202 AM EST THU MAR 3 2016
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE REGION
TONIGHT WITH GRADUALLY DIMINISHING WINDS AND CLEARING SKIES. DRY
WEATHER IS EXPECTED ON THURSDAY WITH A MOSTLY SUNNY SKY AND COOL
TEMPERATURES. A STORM SYSTEM PASSING TO THE SOUTH WILL ALLOW FOR
SOME POSSIBLE LIGHT SNOW TO AREAS SOUTH OF ALBANY ON THURSDAY NIGHT
INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 200 AM EST...QUICK UPDATE TO ACCOUNT FOR SOME SNOW SQUALLS
THAT HAVE DEVELOPED IN PORTIONS OF THE MOHAWK VALLEY AND SCHOHARIE
VALLEY. A COMBINATION OF THE LINGERING UPPER-LEVEL
TROUGH...TRAPPED LOW-LEVEL MOISTURE AND STEEP LOW-LEVEL LAPSE
RATES ARE LIKELY PROVIDING THE FORCING MECHANISMS FOR THESE
SQUALLS. HAVE ISSUED A SPECIAL WEATHER STATEMENT TO ADDRESS A
QUICK INCH OF ACCUMULATION IN LESS THAN AN HOUR AS WELL FOR
LOCALIZED HAZARDOUS TRAVEL CONDITIONS ALONG INTERSTATE 88 WITH
NEAR ZERO VISIBILITY UNDERNEATH THE SQUALL. MESOSCALE GUIDANCE
INCLUDING THE HRRR HAS NOT CAPTURED THIS ACTIVITY WELL IF AT
ALL...AND HAVE ADJUSTED THE GRIDS OVER THE NEXT FEW HOURS USING A
NOWCAST APPROACH.
THESE SNOW SQUALLS AND SHOWERS LOOK TO CONTINUE FOR AT LEAST
BEFORE ENDING. ACROSS THE REST OF THE REGION...IT WILL BE DRY
WITH SKIES BECOMING MOSTLY CLEAR BY DAYBREAK.
WEST TO NORTHWEST WINDS CONTINUE TO SLOWLY SUBSIDE ACROSS THE
REGION...BUT A FEW SPORADIC GUSTS AROUND 25 MPH WILL BE POSSIBLE
FOR THE NEXT FEW HOURS ESPECIALLY DOWN THE MOHAWK VALLEY INTO
PORTIONS OF THE CAPITAL REGION AND BERKSHIRES. AS THE HIGH
PRESSURE CONTINUES TO BUILD INTO THE REGION...WINDS TOWARDS
DAYBREAK SHOULD FEATURE GUSTS LESS THAN 15 MPH FOR MOST AREAS.
OVERNIGHT LOWS WILL BE CHILLY...WITH TEENS FOR MOST AREAS. SOME
SINGLE DIGITS WILL BE POSSIBLE FOR THE ADIRONDACKS...WESTERN
MOHAWK VALLEY...LAKE GEORGE AREA...SOUTHERN VT...AND THE EASTERN
CATSKILLS. ACROSS FAR NORTHERN HERKIMER AND HAMILTON
COUNTIES...LOWS AROUND 0 TO 5 BELOW ZERO WILL BE POSSIBLE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
DRY AND QUIET WEATHER IS EXPECTED ON THURSDAY WILL A MOSTLY SUNNY
SKY THANKS TO NEARBY HIGH PRESSURE. IT WILL BE COOLER THAN
NORMAL...WITH HIGHS IN THE UPPER TEENS TO UPPER 20S ACROSS MUCH OF
THE AREA...ALTHOUGH PARTS OF THE MID HUDSON VALLEY AND NW CT
SHOULD RISE INTO THE LOW TO MID 30S THANKS TO PLENTY OF SUNSHINE
AND A DOWNSLOPING BREEZE.
SOME CLOUDS WILL INCREASE ON THURSDAY NIGHT AS AN UPPER LEVEL
SHORTWAVE STARTS TO APPROACH FROM THE WEST. SFC LOW PRESSURE WILL
BE TRACKING ACROSS THE DEEP SOUTH AND TENNESSEE VALLEY TOWARDS
THE MID ATLANTIC COAST FOR THURSDAY NIGHT INTO FRIDAY. THIS SYSTEM
WILL GENERALLY STAY SOUTH OF THE AREA. HOWEVER...IT COULD BE CLOSE
ENOUGH TO BRUSH FAR SOUTHERN AREAS WITH SOME LIGHT SNOW FOR LATE
THURSDAY NIGHT INTO FRIDAY MORNING. A COATING TO AN INCH IS
POSSIBLE FOR PARTS OF THE CATSKILLS...MID HUDSON VALLEY AND NW CT.
PARTS OF THE CAPITAL REGION MAY SEE SOME SNOWFLAKES AT SOME
POINT...BUT LITTLE TO NO ACCUMULATION IS EXPECTED FROM ALBANY
NORTHWARD. OTHERWISE...MOSTLY CLOUDY AND CHILLY CONDITIONS WILL
CONTINUE. LOWS ON THURSDAY NIGHT WILL BE IN THE SINGLE DIGITS AND
TEENS...WITH HIGHS ON FRIDAY INTO THE 20S TO LOW 30S.
BEHIND THE DEPARTING SHORTWAVE...MAINLY DRY AND QUIET WEATHER WILL
RETURN FOR FRI NIGHT INTO SATURDAY. SKIES WILL BE PARTLY TO MOSTLY
CLEAR. TEMPS WILL BE IN THE SINGLE DIGITS AND TEENS ONCE AGAIN FOR
FRI NIGHT...WITH HIGHS IN THE 30S FOR MOST AREAS ON SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE BUILDS INTO THE REGION SATURDAY NIGHT AND SUNDAY WITH
A WEAK WAVE OF LOW PRESSURE TRACKING WELL SOUTH AND EAST OF OUR
REGION. SOME ISOLATED RAIN/SNOW SHOWERS ARE POSSIBLE IN THE MID
HUDSON VALLEY AND NW CT SATURDAY NIGHT INTO SUNDAY ON THE FAR
NORTHWEST PERIPHERY OF THIS WAVE OF LOW PRESSURE. HIGHS SUNDAY IN
THE LOWER TO MID 40S...SOME MID TO UPPER 30S IN NORTHERN AREAS.
HIGH PRESSURE BUILDS EAST AND OFFSHORE SUNDAY NIGHT AND MONDAY WITH
A SURGE OF WARM ADVECTION AND RAPIDLY WARMING BOUNDARY LAYER
TEMPERATURES. SOME ISOLATED TO SCATTERED RAIN AND SNOW SHOWERS IN
NORTHERN AREAS MONDAY AS THE BOUNDARY LAYER THERMAL GRADIENT
TIGHTENS UP THERE ASSOCIATED WITH THE WARM FRONT DEVELOPING TO OUR
NORTH. THE FORCING SHOULD SUPPORT SCATTERED TO ISOLATED SHOWERS
MONDAY THROUGH WEDNESDAY IN NORTHERN AREAS BUT ONLY ISOLATED TO
SCATTERED BECAUSE OF LIMITED MOISTURE.
BOUNDARY LAYER TEMPERATURES WARM CONSIDERABLY MONDAY THROUGH
WEDNESDAY AS UPPER RIDGING AMPLIFIES OVER THE EASTERN U.S. HIGHS
MONDAY IN THE 40S TO AROUND 50. HIGHS TUESDAY IN THE MID TO UPPER
50S...BUT AROUND 50 NORTHERN AREAS. HIGHS WEDNESDAY POTENTIALLY INTO
THE 60S WITH UPPER 50S NORTHERN AREAS.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
MAINLY VFR THROUGH THE TAF PERIOD ENDING AT 06Z FRIDAY.
THERE STILL COULD BE SOME MVFR CIGS HANGING AROUND AT KPSF THROUGH
10Z...SO WE ASSIGNED A TEMPO GROUP THERE.
OTHERWISE THERE WILL SKC-SCT040 TODAY WITH UNLIMITED VISIBILITY.
THE GUSTY NW WINDS HAVE ABATED EXCEPT AT KPSF...AND BY 10Z ALL
THE TAF SITES SHOULD HAVE WINDS AVERAGING AROUND 10KTS (OR A
LITTLE LESS) FROM NW DIRECTION WITH FEW IF ANY SIGNIFICANT GUSTS.
THROUGH 10Z...WE STILL HAVE GUSTS TO 20KTS AT KPSF.
LOOK FOR A NW WIND TO CONTINUE AROUND 10KTS THROUGHOUT TODAY.
A STORM IN THE SOUTHERN STREAM LOOKS TO STAY MAINLY TO OUR SOUTH.
HOWEVER IT WILL SPREAD HIGH CLOUDS OUR WAY DURING THE EVENING PEAK
AND PERHAPS BRING A LITTLE LIGHT SNOW OR FLURRIES TO THE KPOU
BY THE END OF THE 06Z TAF CYCLE. FOR NOW...WENT WITH JUST VCSH BY
05Z AT KPOU AND WILL FINE TUNE ANY PROJECTED SNOWFALL THAT COULD
LOWER CONDITIONS TO MVFR OR IFR WITH THE 12Z TAF ISSUANCE.
OUTLOOK...
THURSDAY NIGHT THROUGH FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT
CHANCE OF SN.
FRIDAY NIGHT THROUGH MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
NO HYDROLOGIC CONCERNS OVER THE NEXT SEVERAL DAYS.
MAINLY DRY WEATHER IS ANTICIPATED FOR THE REMAINDER OF THE WEEK
AND THROUGH THE WEEKEND. THERE IS THE POSSIBILITY OF SOME LIGHT
SNOW FOR FAR SOUTHERN AREAS FOR THURSDAY NIGHT INTO FRIDAY...BUT
TOTAL LIQUID EQUIVALENT WILL GENERALLY BE LESS THAN A TENTH OF AN
INCH...WHICH WILL HAVE LITTLE TO NO HYDROLOGIC IMPACT.
AS A RESULT OF THE DRY AND RELATIVELY COLD WEATHER...RIVER AND
STREAMS LEVELS WILL CONTINUE TO EITHER SLOWLY RECEDE OR HOLD
STEADY. THE COLD WEATHER OVER THE NEXT FEW DAYS MAY ALLOW FOR
SOME ICE TO BUILD...BUT MILDER WEATHER IS ANTICIPATED BY THE END
OF THE WEEKEND AND INTO EARLY NEXT WEEK.
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...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/IRL
NEAR TERM...IRL
SHORT TERM...FRUGIS
LONG TERM...NAS
AVIATION...HWJIV
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS KEY WEST FL
1013 PM EST FRI MAR 4 2016
.DISCUSSION...
.CURRENTLY...SKIES ARE PARTLY CLOUDY WITH TEMPERATURES IN THE LOWER
70S ALONG KEYS COMMUNITIES. MEANWHILE...LOCAL RADARS ARE NOT
DETECTING ANY PRECIPITATION ECHOES IN OUR REGION. OTHERWISE...OUR
EVENING SOUNDING REVEALS LIMITED MOISTURE BELOW 850 MB...AS WELL AS
ABOVE 400 MB. A SHALLOW NORTHWEST TO NORTH FLOW TURNS WEST NORTHWEST
AND INCREASES APPRECIABLY ABOVE 800 MB.
&&
.SHORT TERM (REST OF TONIGHT)...A SNAKE LIKE TROUGH/WEAK COLD FRONT
DRAPED ACROSS SOUTH CENTRAL FLORIDA AND THE ADJACENT ATLANTIC AND
GULF WATERS WILL SAG SOUTHWARD...WHILE AN EXPANSIVE AREA OF HIGH
PRESSURE BRIDGES ACROSS THE FRONTAL BOUNDARY. GIVEN THE LOW LEVEL
FLOW VEERING TO NORTHEAST AND INCREASING...BOTH THE HRRR AND LOCAL
WRF MODELS INDICATE ISOLATED SHOWERS APPROACHING THE UPPER KEYS AT
AROUND DAYBREAK. MEANWHILE...A LIGHT...ALBEIT STEADY MOSTLY NORTH
WIND BLOWING ACROSS WARM GULF AND BAY WATERS SHOULD KEEP LOW
TEMPERATURES NEAR 70 DEGREES. WITH NICKLE POPS IN THE GRIDS AND
TEMPERATURES IN LINE...SEE NO REASON FOR AN ADJUSTMENT.
&&
.MARINE...NORTHWEST TO NORTH WINDS SHOULD TURN NORTH NORTHEAST AND
INCREASE INTO THE 10 TO 15 KNOT RANGE OVERNIGHT.
OTHERWISE...ISOLATED SHOWERS WILL BE RETAINED ON THE FLORIDA
STRAITS.
&&
.AVIATION...A WEAK FRONT WILL PUSH THROUGH THE EYW AND MTH TERMINALS
OVERNIGHT. NORTHERLY CROSSWIND GUSTS WILL TEMPORARILY INCREASE TO 15
KNOTS AS THIS FRONT REACHES THE TERMINALS BETWEEN 06 AND 12Z.
FORECAST SOUNDINGS INDICATE A STRATUS LAYER AROUND 010 WILL
ACCOMPANY THE WEAK SURGE IN NORTHERLY WINDS. ALTHOUGH GUIDANCE SEEMS
SURE OF THIS SCENARIO...THE PHYSICAL MECHANISMS DO NOT SUPPORT
STRATUS CIGS. THEREFORE...WE HAVE ADVERTISED ONLY A BRIEF MVFR CIG
AT BOTH TERMINALS OUT OF RESPECT FOR THE CONSENSUS AMONG THE MODEL
GUIDANCE.
&&
.CLIMATE... IN 1980...THE DAILY RECORD LOW TEMPERATURE OF 49F WAS
RECORDED IN KEY WEST. TEMPERATURE RECORDS HAVE BEEN KEPT SINCE 1872
&&
.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE.........APA
AVIATION/NOWCASTS.....CR
DATA COLLECTION.......EV
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
547 PM CST FRI MAR 4 2016
.SHORT TERM...
200 PM CST
THROUGH SATURDAY...
ALL REMAINS ON TRACK FOR A QUICK SHOT OF SNOW TONIGHT ESPECIALLY
ALONG AND NORTH OF I-80. THE PRIMARY IMPACT LOOKS TO BE SHARPLY
REDUCED VISIBILITY FOLLOWED BY A QUICK COATING OF SNOW ON SOME
PAVED SURFACES.
THE CENTER OF THE MAIN CLIPPER SHORT WAVE IS IN WESTERN MINNESOTA
EARLY THIS AFTERNOON. AS ITS DRIVING JET SPREAD INTO OUR REGION
THIS EVENING...HEIGHT FALLS AND ASSOCIATED LIFT WILL MAXIMIZE OVER
WISCONSIN AND NORTHERN ILLINOIS. STEEPER MID-LEVEL LAPSE RATES
OBSERVED ON UPSTREAM MORNING SOUNDINGS AND EARLY AFTERNOON
AIRCRAFT DATA FROM OMAHA WILL CONTINUE TO SPREAD EASTWARD WITHIN
THE WARM ADVECTION ZONE SOUTH OF THE VORTICITY CENTER. AS THIS
CATCHES UP TO THE LIFT AND SATURATION...THE AREA OF PRECIPITATION
PRESENTLY IN MN/NORTHERN IA SHOULD SHOW SOUTHEAST EXPANSION AND
PROBABLY INTENSIFICATION DURING THE EARLY TO MID EVENING WHICH
CORRELATES TO WHEN IT IS OVER THE AREA.
HAVE ONLY MADE FURTHER REFINEMENTS TO HOURLY TIMING OF
PRECIPITATION WHICH LOOKS TO BE MAINLY WET SNOW THIS EVENING
ESPECIALLY IN NORTHEAST ILLINOIS AND FAR NORTHWEST INDIANA. ONSET
OF PRECIPITATION COULD BRIEFLY BE A MIX WITH RAIN...AND TOWARD
I-39 IT COULD REMAIN A MIX OR EVEN JUST RAIN SHOWERS THIS EVENING.
BECAUSE OF THE QUICK MOVEMENT OF THE FORCING AND FOCUS...THE
SNOWFALL LOOKS TO LAST TWO HOURS OR LESS IN MOST LOCATIONS...WITH
THE MODERATE INTENSITY EVEN A SHORTER SPAN. CONVECTIVE ALLOWING
MODELS CONTINUE TO SUPPORT THIS IN THEIR REFLECTIVITY...
VISIBILITY...AND HOURLY SNOWFALL FORECASTS. THE PRIMARY TIMING
FOR THE CHICAGO METRO LOOKS TO BE BETWEEN 9 PM AND MIDNIGHT.
WETTER QUALITY OF THE SNOW AND TEMPERATURES OF 31-35 SHOULD LIMIT
MUCH FOR ACCUMULATION ON PAVEMENT...THOUGH GRASSY SURFACES WILL
PROBABLY SEE A QUICK COAT IN NORTH OF I-80 COMMUNITIES. SOUTH OF
I-80 MORE LIMITED TIME AND FORCING FOR SATURATION WILL PROVIDE
MORE VIRGA /RADAR ECHOES NOT REACHING THE GROUND/ THAN
PRECIPITATION...SO NO ACCUMULATION FORECAST.
LOSS OF ICE HAPPENS RAPIDLY BY MIDNIGHT WHICH MAKES SENSE GIVEN
UPSTREAM SATELLITE TRENDS. LOW-LEVEL SATURATION AND LIFT STILL ARE
PROVIDED ON RAP AND NAM SOUNDINGS EVEN THROUGH DAYBREAK. SO
CONTINUE FORECAST DRIZZLE CHANCES. THE TEMPERATURES SHOULD BE
INCHING UP LATE TONIGHT SO NOT TOO CONCERNED ON FREEZING DRIZZLE
BUT DO INDICATE THE BRIEF POSSIBILITY IN THE FORECAST WHERE OUR
DETERMINISTIC TEMPERATURE FORECASTS OUR 30-32 FOR A FEW HOURS.
HAVE TRENDED MORE CLOUDY FOR SATURDAY ESPECIALLY FOR THE EASTERN
HALF OF THE CWA. HAVE DONE SO AS THE CLIPPER BROADENS TO OUR
NORTHEAST AND KEEPS CYCLONIC FLOW ACROSS THE REGION. CLEARING
SHOULD OCCUR FROM WEST-TO-EAST SOMETIME IN THE AFTERNOON THROUGH
IT COULD TAKE UNTIL EARLY SATURDAY EVENING. HAVE HIGHS AROUND
NORMAL WITH 40 EAST TO 45 WEST.
MTF
&&
.LONG TERM...
213 PM CST
SATURDAY NIGHT THROUGH FRIDAY...
A SHIFT TOWARDS A WARM AND ACTIVE SPRING-LIKE PATTERN IS EXPECTED
TO OCCUR LATE IN THE WEEKEND INTO EARLY NEXT WEEK BRINGING
UNSEASONABLY WARM CONDITIONS AS WELL AS PERIODIC CHANCES FOR
SHOWERS AND THUNDERSTORMS.
BY SATURDAY NIGHT...SURFACE RIDGE IS EXPECTED TO BUILD ACROSS
NORTHERN ILLINOIS AND NORTHWEST INDIANA BRINGING QUIET CONDITIONS
BUT FAVORABLE FOR RADIATIONAL COOLING...AND WHAT LOOKS TO BE OUR
COLDEST NIGHT OVER THE UPCOMING WEEK. FORECASTING LOWS IN THE 20S
ACROSS THE FORECAST AREA...HOWEVER WOULDNT BE SURPRISED TO SEE A
FEW OF THE TYPICAL COLD SPOTS DIPPING INTO THE TEENS.
HIGH PRESSURE WILL SHIFT TO OUR EAST SUNDAY WITH SOUTHERLY FLOW
OVERSPREADING THE REGION. THE HIGH IS PROGGED TO BECOME ANCHORED
JUST OFF THE SOUTHEASTERN ATLANTIC COAST WHILE UPPER LEVEL PATTERN
CONTINUES TO AMPLIFY WITH STRONG EAST COAST UPPER RIDGE
DEVELOPING BY THE MIDDLE OF NEXT WEEK AND DEEP TROUGHING
DEVELOPING ACROSS THE WESTERN CONUS. LOCALLY THIS WILL MEAN A
WARMING TREND THROUGH TUESDAY WHEN TEMPERATURES ARE FORECAST TO
RISE INTO THE MID 60S ACROSS NORTHERN ILLINOIS AND NORTHWEST
INDIANA. AS DEEP TROUGHING MOVES OVER THE MID SECTION OF THE
COUNTRY...WE WILL SET THE STAGE FOR SEVERE WEATHER TO OCCUR ACROSS
PORTIONS OF THE PLAINS AND MIDWEST EARLY NEXT WEEK AND WHILE ITS
TOO EARLY TO HONE IN ON SPECIFICS FOR SEVERE WEATHER...MODELS DO
SHOW INSTABILITY BUILDING THIS FAR NORTH SO A THUNDERSTORM MENTION
IS INCLUDED IN THE FORECAST FOR NOW...MAINLY ON TUESDAY FOR OUR
AREA. UPPER LOW EXPECTED TO CUT OFF ACROSS THE DEEP SOUTH AROUND
MIDWEEK AND EVENTUALLY MEANDER ACROSS THE MIDWEST LATE IN THE
WEEK OR NEXT WEEKEND. DETAILS REMAIN UNCLEAR AT THIS POINT BUT IT
DOES APPEAR WE WILL GENERALLY STAY IN A WARMER AND WETTER PATTERN
LATE IN THE WEEK INTO NEXT WEEKEND.
DEUBELBEISS
&&
.AVIATION...
FOR THE 00Z TAFS...
MAIN CONCERN FOR THE TAFS CONTINUES TO BE WITH A COUPLE HOUR
PERIOD SNOW THIS EVENING WITH BRIEF LIFR VISIBILITY. PRECIPITATION
COULD START WITH A BRIEF MIX OF RAIN/SNOW. TEMPS HANG NEAR 32 THEN
RISE A BIT AFTER MIDNIGHT WITH DRIZZLE AND THE POTENTIAL FOR IFR
CIGS...FARILY HIGH PROBABILITY OF MVFR CIGS WHICH LINGER A GOOD
PORTION OF THE DAY SATURDAY.
AREA OF LOW PRESSURE WAS OVER MINNESOTA LATE THIS AFTERNOON...WITH
A COMPACT BUT POTENT MID-LEVEL DISTURBANCE TRACKING SOUTHEAST
ACROSS THE REGION. A BAND OF PRECIPITATION ABOUT 100 MILES WIDE
HAS DEVELOPED AHEAD OF THE MID-LEVEL TROUGH...AND WILL BRING A
PERIOD OF MODERATE...POSSIBLY BRIEFLY HEAVY...PERIOD OF SNOW TO
THE AREA. START TIME IS A LITTLE TRICKIER THAN THE END TIME...AS
RADAR ECHOES PRESENT WITH LITTLE PRECIP REACHING THE GROUND
INITIALLY AS ATMOSPHERE SATURATES FROM TOP-DOWN...BUT IT APPEARS
BY 0230-300Z SNOW SHOULD BE REACHING THE GROUND INTO ORD/MDW.
TRAILING EDGE MORE SOLIDLY DEFINED AND IS EXPECTED TO REACH
ORD/MDW AROUND 06Z/MIDNIGHT. UPSTREAM OBS INDICATE LIFR VSBY AND
IFR CIGS WITH HEAVIEST SNOW. DESPITE INTENSITY...SHORT DURATION
LOOKS TO PRODUCE AMOUNTS ONLY OF UP TO 1 INCH.
LOW LEVEL MOISTURE THEN WRAPS AROUND FROM THE NORTHWEST OVERNIGHT
WITH SOME DRIZZLE LIKELY. TEMPS AROUND FREEZING INITIALLY SHOULD
RISE ABOVE FREEZING OVERNIGHT WITH LITTLE IMPACT. BREEZY NORTHWEST
WINDS GUSTING 20 KT DEVELOP SATURDAY. MVFR CIGS LIKELY TO LINGER
BEFORE ERODING LATE IN THE DAY.
RATZER
&&
.MARINE...
213 PM CST
A CLIPPER LIKE SNOW SYSTEM WILL DROP ACROSS THE UPPER MIDWEST AND
WESTERN GREAT LAKES REGION TODAY WITH MODERATE SOUTHERLY FLOW OF
20 TO 25 KT EXPECTED AHEAD OF THIS SYSTEM THIS EVENING AND
TONIGHT. THE LOW WILL CROSS OVER THE SOUTHERN HALF OF LAKE
MICHIGAN ON SATURDAY WITH WINDS TURNING NORTHERLY BEHIND...THEN
DIMINISHING AS HIGH PRESSURE BEGINS TO BUILD OVERHEAD FOR SATURDAY
NIGHT. THE HIGH WILL CONTINUE TO THE SOUTHEAST STATES AND
EVENTUALLY SET UP NEAR BERMUDA WHERE IT WILL REMAIN ANCHORED MUCH
OF THE UPCOMING WEEK WHICH WILL HELP DRIVE A MAJOR PATTERN CHANGE
ACROSS THE REGION. LOW PRESSURE DEVELOPS OVER THE PLAINS SUNDAY
INTO EARLY NEXT WEEK WITH SOUTHERLY FLOW RAMPING BACK UP AGAIN TO
AROUND 30 KT SUNDAY. MODERATE SOUTHERLY FLOW OF 20 TO 25 AND
OCCASIONALLY 30 KT WILL CONTINUE THROUGH TUESDAY HELPING SPREAD AN
UNSEASONABLY WARM AND MOIST AIRMASS INTO THE GREAT LAKES. THE HIGH
DEWPOINTS ARE EXPECTED TO RESULT IN AREAS OF FOG DEVELOPING OVER
THE LAKE. ALSO CANNOT RULE OUT SOME THUNDERSTORMS...PARTICULARLY
ON TUESDAY.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
301 PM CST THU MAR 3 2016
.SHORT TERM...(Tonight)
ISSUED AT 301 PM CST THU MAR 3 2016
19z/1pm surface analysis shows a 1010mb low over Arkansas, with a
trough axis extending northward into central Illinois. Light rain
continues to fall in the vicinity of the trough, but has now pushed
mainly east of the Illinois River. This feature is progged to be
located along the I-57 corridor by 00z, so am expecting some light
precip to linger across the E/SE CWA into the evening hours. As
winds become northerly on the back side of the trough, the
atmosphere will cool sufficiently to support a light rain/snow mix.
Based on latest trends and HRRR forecast, have included low chance
PoPs along/east of a Bloomington to Flora line this evening. Will
mention rain or snow north of the I-70 corridor: however, no snow
accumulation is expected. Once the trough pushes off to the east,
cloudy and cool conditions will prevail for the remainder of the
night with low temperatures dropping into the upper 20s and lower
30s.
&&
.LONG TERM...(Friday through Thursday)
ISSUED AT 301 PM CST THU MAR 3 2016
High pressure will move quickly across the state Friday with
partly sunny skies for the late morning and early afternoon and
slightly milder temperatures. Another storm system passing across
Wisconsin Friday night, with a trailing cold front and shortwave
passing through central IL will increase mid and high clouds and
southerly winds late in the day Friday, and bring at least a slight
chance for precipitation or drizzle overnight. There is some
question about precipitation type as temperatures will cool off to
become somewhat marginal for snow late in the night, however
precipitation should be mainly rain throughout central IL, with
perhaps a brief change to a mix of snow and rain toward the end of
precipitation Saturday morning. Even with temperatures cooling close
to freezing late in the night, moisture depth may drop off too
dramatically for anything more than liquid drizzle to form at that
point.
A trend toward warmer temperatures is then in store for Saturday
through Tuesday as a high pressure ridge shifts eastward to the
central and eastern U.S. Highs on Saturday range from 45 in
Galesburg to 55 in Lawrenceville...and are expected to increase to
the mid and upper 60s by Tuesday. Meanwhile, lows Saturday night are
expected to cool to a few degrees below freezing, but should trend
upward to the low 50s by Monday night.
A series of small waves ejecting out of a trough over the
western states will bring periodic chances for showers and some
thunderstorms through central and southeast IL for much of the
upcoming work week. Temperatures should remain mild, with highs in
the 50s or 60s through midweek, and lows generally 40s or low 50s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1156 AM CST THU MAR 3 2016
IFR ceilings have developed over the past couple of hours and will
persist through the early afternoon. Forecast soundings suggest
MVFR ceilings will return after the 20-22z time frame. Based on
radar trends and latest Rapid Refresh forecast, it appears light
snow will taper off at KPIA at 18z...with light rain ending
further east at KCMI by around 22z. As low pressure passes to the
south of Illinois, winds will gradually swing around to the north
at all terminals by early evening. Northerly winds are then
expected to continue through the night before becoming
light/variable by Friday morning. Clearing appears to be delayed
from previous forecasts, with all models suggesting MVFR ceilings
continuing through the night. Have scattered the clouds as per NAM
soundings between 14z and 16z Fri.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Onton
AVIATION...Barnes
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
227 AM CST THU MAR 3 2016
.UPDATE...
826 PM CST
FOR EVENING UPDATE...
HAVE MADE SOME MINOR ADJUSTMENTS TO HOURLY POP/WX BASED ON
CURRENT OBS AND RECENT HIGH-RES GUIDANCE RUNS...PRIMARILY TO
TIGHTEN UP POP GRADIENTS THROUGH THIS EVENING AND TO ADD SOME
DETAIL TO TIMING OF SNOW ONSET FROM PARTS OF NORTH CENTRAL IL NEXT
COUPLE OF HOURS INTO PARTS OF CHICAGO/KANKAKEE AREAS BY/SHORTLY
AFTER MIDNIGHT. BASED ON TRENDS FROM 18Z 4KM NAM AND SEVERAL
RECENT HRRR RUNS HAVE ELECTED TO INCLUDE KANKAKEE COUNTY IN THE
WINTER WEATHER ADVISORY...WITH GUIDANCE FOCUSING BETTER (2-4)
SNOW ACCUMULATION AXIS GENERALLY ALIGNING ALONG AN AXIS FROM SQI-
VYS-JOT-IKK AREAS.
MID-EVENING REGIONAL RADAR MOSAIC DEPICTING PATCHY BANDED RETURNS
DEVELOPING ACROSS ESPECIALLY WEST/SOUTHWEST COUNTIES OF IL PORTION
OF CWA. STRONGER (20-25 DBZ) ECHOES HAVE BEEN SOMEWHAT TRANSIENT
IN FORMING/WEAKENING IN REGIONS OF WEAK MID-LEVEL FRONTOGENETIC
FORCING WHICH GUIDANCE SUGGESTS WILL BE SOMEWHAT WEAKLY FOCUSED
OVERNIGHT. DRY LOW-LEVEL AIR ALSO HELPING TO KEEP BETTER RETURNS
LIMITED INITIALLY THIS EVENING...WITH FAIRLY LARGE TEMP-DEW POINT
SPREADS BELOW ABOUT 700 MB AS DEPICTED BY EARLY EVENING AMDAR
SOUNDINGS OUT OF ORD/MDW. GRADUALLY SEEING MORE CLOUD LAYERS BELOW
5000 FT HOWEVER AND SAVANNA IL (KSFY) ALONG THE MISSISSIPPI TO OUR
WEST NOW REPORTING 3SM IN LIGHT SNOW...SO LIGHT SNOW IS LIKELY
FAIRLY SOON ACROSS IL COUNTIES WEST/SOUTHWEST OF CHICAGO.
FRONTOGENETIC BANDING IS LIKELY TO REMAIN A BIT TRANSIENT BASED ON
RELATIVELY UNIMPRESSIVE F-GEN FIELDS IN VARIOUS MODELS DURING THE
DURATION OF THIS EVENT...THOUGH PERSISTENT MOIST ISENTROPIC ASCENT
APPEARS TO MAXIMIZE FORCING AROUND THE 285 K SURFACE INTO
THURSDAY. WHILE MUCH OF THE DEEPER ASCENT DIRECTLY AHEAD OF THE
PRIMARY VORT TRACK LOOKS TO REMAIN SOUTH OF THE CWA...GUIDANCE HAS
REMAINED FAIRLY CONSISTENT IN MAINTAINING AN AXIS OF GREATEST QPF
FROM SQI/VYS THROUGH JOT/IKK AREAS...WHERE IT APPEARS AMOUNTS OF
3-4 INCHES ARE MOST LIKELY. AMOUNTS SHOULD TAPER OFF TO 1-2
ALONG/NORTH OF THE I-90 CORRIDOR...AND INTO CENTRAL IL/IN WHERE
THERMAL PROFILES BECOME MARGINAL FOR ALL SNOW DURING THE DAY
THURSDAY. ISENTROPIC DOWNGLIDE DEVELOPS THURSDAY AFTERNOON
RESULTING IN SNOW TAPERING OFF FROM WEST TO EAST ESPECIALLY LATER
IN THE AFTERNOON AND EARLY EVENING.
SO OVERALL...TRIED TO TIGHTEN UP POP/QPF/SNOW AMOUNT AXIS JUST A
BIT BASED ON RECENT GUIDANCE TRENDS...ALONG WITH ADDING KANKAKEE
COUNTY TO THE WINTER WEATHER ADVISORY. NO BIG DEAL...BUT TIMING
WILL IMPACT MORNING COMMUTE.
RATZER
&&
.SHORT TERM...
258 PM CST
THROUGH THURSDAY...
BOTTOM LINE UP FRONT...SNOW WILL BE MOVING IN LATE THIS EVENING FROM
WEST TO EAST AND PERSIST INTO THURSDAY. HAVE ISSUED A WINTER
WEATHER ADVISORY FOR THE COUNTIES BETWEEN 1-88 AND 1-80. THIS
ADVISORY IS STRICTLY FOR IMPACTS TO THE MORNING RUSH FROM THE SNOW
AS WE WILL LIKELY NOT SEE WIDESPREAD 3-5 INCHES OF SNOW. SNOW WILL
PICK UP IN THE MORNING AFTER 4AM WITH MODERATE SNOW CONTINUING
THROUGH THE MORNING RUSH HOUR. SNOW SHOULD TAPER DOWN TO STEADY
LIGHT SNOW IN THE MID TO LATE MORNING AND THEN END FROM WEST TO
EAST IN THE AFTERNOON. ONCE AGAIN...ONLY EXPECTING 2-4 INCHES OF
SNOW IN THE ADVISORY AREA...WITH SNOW PICKING UP AND IMPACTING THE
MORNING RUSH HOUR. EXPECTING THE BEST CHANCE FOR AMOUNTS UP TO 4
INCHES TO BE FROM SOUTHWEST KANE COUNTIES SOUTHWARD TO GRUNDY
COUNTY AND POINTS WEST...INCLUDING THE MENDOTA AND AMBOY AREAS.
TONIGHT...HIGH PRESSURE SHIFTS EAST AND CLOUD COVER INCREASES. LIGHT
WINDS BACK TO SOUTHEAST AND THEN EAST BY SUNRISE. THE LOW CURRENTLY
FORMING OVER THE PLAINS REACHES THE ARKLATEX REGION BY EARLY
THURSDAY MORNING. SNOW SPREADS FROM WEST TO EAST LATE THIS EVENING
AND OVERNIGHT WITH A LIGHT STEADY SNOW EXPECTED. SURFACE TEMPS
SHOULD ALLOW SNOW TO ACCUMULATE QUITE EASILY. HAVE HIGH CONFIDENCE
IN ACCUMULATING SNOW NORTH OF A PONTIAC IL TO RENSSELAER IN LINE
OVERNIGHT. AREAS SOUTH OF THAT LINE MAY SEE A BREAK IN SNOW
OVERNIGHT DUE TO DRY AIR MOVING INTO THE LOW LEVELS OF THE
ATMOSPHERE. LEFT A CHANCE OF SNOW IN THE FORECAST BECAUSE SNOW MAY
SATURATE THE LOW LEVELS AND LEAD TO VERY LIGHT SNOW. HAVE MEDIUM
CONFIDENCE IN SNOW SOUTH OF THE PONTIAC TO RENSSELAER LINE OVERNIGHT.
THURSDAY...SNOW INTENSIFIES EARLY THURSDAY MORNING DURING RUSH HOUR.
SNOW RATES INCREASE TO AROUND A HALF INCH PER HOUR...BUT THE
BIGGER IMPACTS WILL BE VISIBILITIES OF LESS THAN A MILE AT TIMES.
PERIODS OF 1/2SM VISIBILITY IS VERY PSBL...WHICH WILL IMPACT
TRAVEL CONDITIONS IN ADDITION TO SNOW COVERED AND SLIPPERY ROADWAYS.
EXPECTING THE INCREASE IN SNOW INTENSITY BECAUSE OMEGA INCREASES
JUST BELOW THE DGZ ACCORDING TO FORECAST SOUNDINGS. COULD SEE
HIGHER SNOWFALL RATES AND LOWER VISIBILITIES IF THE FORCING ALIGNS
BETTER WITH THE DGZ. WINNEBAGO THROUGH LAKE IL COUNTIES IN FAR
NORTHERN IL WILL SEE LOWER SNOWFALL AMOUNTS WITH THE BAND OF
MODERATE SNOW JUST TO THE SOUTH...WHICH IS WHY THESE COUNTIES ARE
NOT IN THE ADVISORY.
AREAS WELL SOUTH OF 1-80 WILL WARM TO ABOVE FREEZING THURSDAY SO
EXPECTING RAIN AND SNOW. THIS WILL LIMIT SNOWFALL AMOUNTS AND IS THE
REASON THIS AREA WAS NOT INCLUDED IN THE ADVISORY. FREEZING RAIN
AND SLEET ARE NOT EXPECTED AS SATURATED SOUNDINGS WARM THROUGH THE
LOWER LEVELS LEADING TO ALL RAIN.
LOWERED WIND SPEEDS FOR THURSDAY WITH EAST WINDS AT 10-15 MPH. AN
OCNL GUST TO 20 MPH IS PSBL. THE SNOW MAY BLOW AROUND A LITTLE...BUT
NOT OVERLY CONCERNED ABOUT BLOWING SNOW AT THIS TIME GIVEN THE LOWER
WIND SPEEDS.
JEE
&&
.LONG TERM...
249 PM CST
THURSDAY NIGHT THROUGH WEDNESDAY...
CONTINUED SEASONABLY COOL BUT PRIMARILY DRY WEATHER IS EXPECTED TO
CLOSE OUT THE WEEK...THEN PATTERN TRANSITIONS TO ONE MORE TYPICAL OF
SPRING WHICH WILL RESULT IN WARMER AND UNSETTLED WEATHER AS WE GET
LATE INTO THE WEEKEND AND INTO NEXT WEEK...
BACK END OF DEFORMATION ZONE FROM DEPARTING LOW MAY RESULT IN SOME
LINGERING LIGHT SNOW MAINLY ACROSS THE EASTERN PORTIONS OF THE
FORECAST AREA THURSDAY EVENING/NIGHT BUT HIGH PRESSURE BUILDING IN
FROM THE WEST WILL RESULT DRY CONDITIONS OVERSPREADING THE REGION BY
FRIDAY MORNING. UPPER LEVEL RIDGE IS PROGGED TO AMPLIFY ACROSS THE
WESTERN CONUS FRIDAY WITH MID LEVEL WAA OVERSPREADING PORTIONS OF
THE MID AND UPPER MISSISSIPPI VALLEY. STILL ON THE COLD SIDE OF THE
BAROCLINIC ZONE FRIDAY...EXPECT HIGHS TO ONLY BE IN THE 30S ACROSS
THE OUTLOOK AREA. MEANWHILE...SHORTWAVE TROUGH RIDING DOWN THE LEE
SIDE OF THE RIDGE IS PROGGED TO DIVE FROM MINNESOTA FRIDAY EVENING
TO ACROSS IL/IN BY MIDDAY SATURDAY. THIS CLIPPER SYSTEM WILL BRING
ADDITIONAL CHANCES FOR SNOW FRIDAY NIGHT INTO EARLY SATURDAY WITH
ACCUMULATING SNOWFALL POSSIBLE.
SURFACE RIDGE BUILDS BACK OVERHEAD SATURDAY EVENING AND NIGHT...THEN
WINDS TURN SOUTHERLY LATE SATURDAY NIGHT INTO SUNDAY WITH THE
BAROCLINIC ZONE FINALLY MAKING A STRONG SURGE ACROSS THE AREA. THIS
WILL RESULT IN A WARMING TREND SUNDAY THROUGH TUESDAY. EXPECT MID
40S NORTH TO LOW 50S SOUTH SUNDAY...AND BY TUESDAY AND WEDNESDAY
THERE IS A POSSIBILITY OF SEEING 60S ACROSS THE ENTIRE OUTLOOK AREA.
DEEPENING UPPER TROUGH OVER THE MID SECTION OF THE COUNTRY WILL BE
IN PLACE WITH SEVERAL SHORTWAVES EJECTING ACROSS PLAINS INTO THE
MIDWEST. THIS WILL SET THE STAGE FOR ACTIVE/WET WEATHER AND POSSIBLY
EVEN A FEW PERIODS OF THUNDERSTORMS AS GUIDANCE SUGGESTS AT LEAST
MODEST INSTABILITY POSSIBLE. UPPER LOW IS PROGGED TO CUT-OFF OVER
THE SOUTHERN PLAINS AFTER MIDWEEK RESULTING IN CONTINUED ACTIVE
WEATHER LATE IN THE WEEK BUT HIGH DEGREE OF UNCERTAINTY IN THE
DETAILS.
BMD
&&
.AVIATION...
FOR THE 06Z TAFS...
LIGHT SNOW WILL CONTINUE OVERNIGHT AND INTO THURSDAY
MORNING...GRADUALLY TAPERING OFF FROM THE NORTH THURSDAY MORNING.
LATEST OBSERVATIONAL TRENDS SUGGEST THAT THE SNOW HAS ERODED THE
LOW LEVEL DRY LAYER AND ANTICIPATE LIGHT SNOW OF VARYING INTENSITY
TO CONTINUE WITH FLUCTUATIONS IN VSBY MOSTLY BETWEEN MVFR AND
IFR...THOUGH BRIEF LIFR VSBY IS POSSIBLE...PARTICULARLY THE MORE
SOUTHERN TERMINALS. AS LOW LEVELS SATURATE...CIGS SHOULD BUILD
DOWN TO IFR BY BY EARLY THURS MORNING AND LIKELY REMAIN IFR
THROUGH THE DAY. COULD SEE SOME FLURRIES LINGER INTO THE
AFTERNOON...PARTICULARLY SOUTH. CIGS LIKELY TO CONTINUE TO
IMPROVE THURSDAY NIGHT.
IZZI
&&
.MARINE...
227 AM...A RIDGE OF HIGH PRESSURE EXTENDS FROM ONTARIO ACROSS THE
EASTERN LAKES TO THE MID ATLANTIC THIS MORNING. THIS RIDGE WILL
MOVE NORTHEAST TODAY AND TONIGHT. LOW PRESSURE OVER THE PLAINS IS
NOW EXPECTED TO MOVE EAST...FURTHER SOUTH AND AS A RESULT THE
GRADIENT DOESN/T APPEAR TO TIGHTEN AS MUCH OVER THE SOUTHERN END
OF THE LAKE. EAST/NORTHEAST WINDS WILL STILL INCREASE BUT SHOULD
DIMINISH FASTER THIS EVENING. SOUTHERLY WINDS WILL INCREASE FRIDAY
INTO FRIDAY NIGHT AHEAD OF LOW PRESSURE MOVING SOUTHEAST FROM THE
NORTHERN PLAINS. THIS LOW WILL BE WEAKENING FRIDAY NIGHT AS IT
CROSSES THE LAKE...BUT THERE COULD BE SOME GUSTS TO 30 KTS AS THE
LOW APPROACHES. THE GRADIENT BRIEFLY TIGHTENS ON SATURDAY AS THE
LOW DEPARTS AND HIGH PRESSURE BUILDS ACROSS THE WESTERN LAKES. A
SHORT PERIOD OF 15-25KT IS POSSIBLE. WINDS WILL DIMINISH SATURDAY
NIGHT AS THE HIGH PASSES OVER THE LAKE AND WINDS WILL TURN
SOUTHERLY SUNDAY AS LOW PRESSURE MOVES ACROSS THE PLAINS SUNDAY
THROUGH TUESDAY. THERE COULD BE SOME GUSTS TO 30KTS SUNDAY NIGHT.
CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ012-ILZ013-ILZ014-ILZ020-ILZ021-
ILZ022-ILZ023 UNTIL 2 PM THURSDAY.
WINTER WEATHER ADVISORY...ILZ008-ILZ010-ILZ011-ILZ019 UNTIL 10
AM THURSDAY.
IN...WINTER WEATHER ADVISORY...INZ001-INZ002 UNTIL 2 PM THURSDAY.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743...6 AM
THURSDAY TO 10 PM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1052 PM CST WED MAR 2 2016
.UPDATE...
826 PM CST
FOR EVENING UPDATE...
HAVE MADE SOME MINOR ADJUSTMENTS TO HOURLY POP/WX BASED ON
CURRENT OBS AND RECENT HIGH-RES GUIDANCE RUNS...PRIMARILY TO
TIGHTEN UP POP GRADIENTS THROUGH THIS EVENING AND TO ADD SOME
DETAIL TO TIMING OF SNOW ONSET FROM PARTS OF NORTH CENTRAL IL NEXT
COUPLE OF HOURS INTO PARTS OF CHICAGO/KANKAKEE AREAS BY/SHORTLY
AFTER MIDNIGHT. BASED ON TRENDS FROM 18Z 4KM NAM AND SEVERAL
RECENT HRRR RUNS HAVE ELECTED TO INCLUDE KANKAKEE COUNTY IN THE
WINTER WEATHER ADVISORY...WITH GUIDANCE FOCUSING BETTER (2-4)
SNOW ACCUMULATION AXIS GENERALLY ALIGNING ALONG AN AXIS FROM SQI-
VYS-JOT-IKK AREAS.
MID-EVENING REGIONAL RADAR MOSAIC DEPICTING PATCHY BANDED RETURNS
DEVELOPING ACROSS ESPECIALLY WEST/SOUTHWEST COUNTIES OF IL PORTION
OF CWA. STRONGER (20-25 DBZ) ECHOES HAVE BEEN SOMEWHAT TRANSIENT
IN FORMING/WEAKENING IN REGIONS OF WEAK MID-LEVEL FRONTOGENETIC
FORCING WHICH GUIDANCE SUGGESTS WILL BE SOMEWHAT WEAKLY FOCUSED
OVERNIGHT. DRY LOW-LEVEL AIR ALSO HELPING TO KEEP BETTER RETURNS
LIMITED INITIALLY THIS EVENING...WITH FAIRLY LARGE TEMP-DEW POINT
SPREADS BELOW ABOUT 700 MB AS DEPICTED BY EARLY EVENING AMDAR
SOUNDINGS OUT OF ORD/MDW. GRADUALLY SEEING MORE CLOUD LAYERS BELOW
5000 FT HOWEVER AND SAVANNA IL (KSFY) ALONG THE MISSISSIPPI TO OUR
WEST NOW REPORTING 3SM IN LIGHT SNOW...SO LIGHT SNOW IS LIKELY
FAIRLY SOON ACROSS IL COUNTIES WEST/SOUTHWEST OF CHICAGO.
FRONTOGENETIC BANDING IS LIKELY TO REMAIN A BIT TRANSIENT BASED ON
RELATIVELY UNIMPRESSIVE F-GEN FIELDS IN VARIOUS MODELS DURING THE
DURATION OF THIS EVENT...THOUGH PERSISTENT MOIST ISENTROPIC ASCENT
APPEARS TO MAXIMIZE FORCING AROUND THE 285 K SURFACE INTO
THURSDAY. WHILE MUCH OF THE DEEPER ASCENT DIRECTLY AHEAD OF THE
PRIMARY VORT TRACK LOOKS TO REMAIN SOUTH OF THE CWA...GUIDANCE HAS
REMAINED FAIRLY CONSISTENT IN MAINTAINING AN AXIS OF GREATEST QPF
FROM SQI/VYS THROUGH JOT/IKK AREAS...WHERE IT APPEARS AMOUNTS OF
3-4 INCHES ARE MOST LIKELY. AMOUNTS SHOULD TAPER OFF TO 1-2
ALONG/NORTH OF THE I-90 CORRIDOR...AND INTO CENTRAL IL/IN WHERE
THERMAL PROFILES BECOME MARGINAL FOR ALL SNOW DURING THE DAY
THURSDAY. ISENTROPIC DOWNGLIDE DEVELOPS THURSDAY AFTERNOON
RESULTING IN SNOW TAPERING OFF FROM WEST TO EAST ESPECIALLY LATER
IN THE AFTERNOON AND EARLY EVENING.
SO OVERALL...TRIED TO TIGHTEN UP POP/QPF/SNOW AMOUNT AXIS JUST A
BIT BASED ON RECENT GUIDANCE TRENDS...ALONG WITH ADDING KANKAKEE
COUNTY TO THE WINTER WEATHER ADVISORY. NO BIG DEAL...BUT TIMING
WILL IMPACT MORNING COMMUTE.
RATZER
&&
.SHORT TERM...
258 PM CST
THROUGH THURSDAY...
BOTTOM LINE UP FRONT...SNOW WILL BE MOVING IN LATE THIS EVENING FROM
WEST TO EAST AND PERSIST INTO THURSDAY. HAVE ISSUED A WINTER
WEATHER ADVISORY FOR THE COUNTIES BETWEEN 1-88 AND 1-80. THIS
ADVISORY IS STRICTLY FOR IMPACTS TO THE MORNING RUSH FROM THE SNOW
AS WE WILL LIKELY NOT SEE WIDESPREAD 3-5 INCHES OF SNOW. SNOW WILL
PICK UP IN THE MORNING AFTER 4AM WITH MODERATE SNOW CONTINUING
THROUGH THE MORNING RUSH HOUR. SNOW SHOULD TAPER DOWN TO STEADY
LIGHT SNOW IN THE MID TO LATE MORNING AND THEN END FROM WEST TO
EAST IN THE AFTERNOON. ONCE AGAIN...ONLY EXPECTING 2-4 INCHES OF
SNOW IN THE ADVISORY AREA...WITH SNOW PICKING UP AND IMPACTING THE
MORNING RUSH HOUR. EXPECTING THE BEST CHANCE FOR AMOUNTS UP TO 4
INCHES TO BE FROM SOUTHWEST KANE COUNTIES SOUTHWARD TO GRUNDY
COUNTY AND POINTS WEST...INCLUDING THE MENDOTA AND AMBOY AREAS.
TONIGHT...HIGH PRESSURE SHIFTS EAST AND CLOUD COVER INCREASES. LIGHT
WINDS BACK TO SOUTHEAST AND THEN EAST BY SUNRISE. THE LOW CURRENTLY
FORMING OVER THE PLAINS REACHES THE ARKLATEX REGION BY EARLY
THURSDAY MORNING. SNOW SPREADS FROM WEST TO EAST LATE THIS EVENING
AND OVERNIGHT WITH A LIGHT STEADY SNOW EXPECTED. SURFACE TEMPS
SHOULD ALLOW SNOW TO ACCUMULATE QUITE EASILY. HAVE HIGH CONFIDENCE
IN ACCUMULATING SNOW NORTH OF A PONTIAC IL TO RENSSELAER IN LINE
OVERNIGHT. AREAS SOUTH OF THAT LINE MAY SEE A BREAK IN SNOW
OVERNIGHT DUE TO DRY AIR MOVING INTO THE LOW LEVELS OF THE
ATMOSPHERE. LEFT A CHANCE OF SNOW IN THE FORECAST BECAUSE SNOW MAY
SATURATE THE LOW LEVELS AND LEAD TO VERY LIGHT SNOW. HAVE MEDIUM
CONFIDENCE IN SNOW SOUTH OF THE PONTIAC TO RENSSELAER LINE OVERNIGHT.
THURSDAY...SNOW INTENSIFIES EARLY THURSDAY MORNING DURING RUSH HOUR.
SNOW RATES INCREASE TO AROUND A HALF INCH PER HOUR...BUT THE
BIGGER IMPACTS WILL BE VISIBILITIES OF LESS THAN A MILE AT TIMES.
PERIODS OF 1/2SM VISIBILITY IS VERY PSBL...WHICH WILL IMPACT
TRAVEL CONDITIONS IN ADDITION TO SNOW COVERED AND SLIPPERY ROADWAYS.
EXPECTING THE INCREASE IN SNOW INTENSITY BECAUSE OMEGA INCREASES
JUST BELOW THE DGZ ACCORDING TO FORECAST SOUNDINGS. COULD SEE
HIGHER SNOWFALL RATES AND LOWER VISIBILITIES IF THE FORCING ALIGNS
BETTER WITH THE DGZ. WINNEBAGO THROUGH LAKE IL COUNTIES IN FAR
NORTHERN IL WILL SEE LOWER SNOWFALL AMOUNTS WITH THE BAND OF
MODERATE SNOW JUST TO THE SOUTH...WHICH IS WHY THESE COUNTIES ARE
NOT IN THE ADVISORY.
AREAS WELL SOUTH OF 1-80 WILL WARM TO ABOVE FREEZING THURSDAY SO
EXPECTING RAIN AND SNOW. THIS WILL LIMIT SNOWFALL AMOUNTS AND IS THE
REASON THIS AREA WAS NOT INCLUDED IN THE ADVISORY. FREEZING RAIN
AND SLEET ARE NOT EXPECTED AS SATURATED SOUNDINGS WARM THROUGH THE
LOWER LEVELS LEADING TO ALL RAIN.
LOWERED WIND SPEEDS FOR THURSDAY WITH EAST WINDS AT 10-15 MPH. AN
OCNL GUST TO 20 MPH IS PSBL. THE SNOW MAY BLOW AROUND A LITTLE...BUT
NOT OVERLY CONCERNED ABOUT BLOWING SNOW AT THIS TIME GIVEN THE LOWER
WIND SPEEDS.
JEE
&&
.LONG TERM...
249 PM CST
THURSDAY NIGHT THROUGH WEDNESDAY...
CONTINUED SEASONABLY COOL BUT PRIMARILY DRY WEATHER IS EXPECTED TO
CLOSE OUT THE WEEK...THEN PATTERN TRANSITIONS TO ONE MORE TYPICAL OF
SPRING WHICH WILL RESULT IN WARMER AND UNSETTLED WEATHER AS WE GET
LATE INTO THE WEEKEND AND INTO NEXT WEEK...
BACK END OF DEFORMATION ZONE FROM DEPARTING LOW MAY RESULT IN SOME
LINGERING LIGHT SNOW MAINLY ACROSS THE EASTERN PORTIONS OF THE
FORECAST AREA THURSDAY EVENING/NIGHT BUT HIGH PRESSURE BUILDING IN
FROM THE WEST WILL RESULT DRY CONDITIONS OVERSPREADING THE REGION BY
FRIDAY MORNING. UPPER LEVEL RIDGE IS PROGGED TO AMPLIFY ACROSS THE
WESTERN CONUS FRIDAY WITH MID LEVEL WAA OVERSPREADING PORTIONS OF
THE MID AND UPPER MISSISSIPPI VALLEY. STILL ON THE COLD SIDE OF THE
BAROCLINIC ZONE FRIDAY...EXPECT HIGHS TO ONLY BE IN THE 30S ACROSS
THE OUTLOOK AREA. MEANWHILE...SHORTWAVE TROUGH RIDING DOWN THE LEE
SIDE OF THE RIDGE IS PROGGED TO DIVE FROM MINNESOTA FRIDAY EVENING
TO ACROSS IL/IN BY MIDDAY SATURDAY. THIS CLIPPER SYSTEM WILL BRING
ADDITIONAL CHANCES FOR SNOW FRIDAY NIGHT INTO EARLY SATURDAY WITH
ACCUMULATING SNOWFALL POSSIBLE.
SURFACE RIDGE BUILDS BACK OVERHEAD SATURDAY EVENING AND NIGHT...THEN
WINDS TURN SOUTHERLY LATE SATURDAY NIGHT INTO SUNDAY WITH THE
BAROCLINIC ZONE FINALLY MAKING A STRONG SURGE ACROSS THE AREA. THIS
WILL RESULT IN A WARMING TREND SUNDAY THROUGH TUESDAY. EXPECT MID
40S NORTH TO LOW 50S SOUTH SUNDAY...AND BY TUESDAY AND WEDNESDAY
THERE IS A POSSIBILITY OF SEEING 60S ACROSS THE ENTIRE OUTLOOK AREA.
DEEPENING UPPER TROUGH OVER THE MID SECTION OF THE COUNTRY WILL BE
IN PLACE WITH SEVERAL SHORTWAVES EJECTING ACROSS PLAINS INTO THE
MIDWEST. THIS WILL SET THE STAGE FOR ACTIVE/WET WEATHER AND POSSIBLY
EVEN A FEW PERIODS OF THUNDERSTORMS AS GUIDANCE SUGGESTS AT LEAST
MODEST INSTABILITY POSSIBLE. UPPER LOW IS PROGGED TO CUT-OFF OVER
THE SOUTHERN PLAINS AFTER MIDWEEK RESULTING IN CONTINUED ACTIVE
WEATHER LATE IN THE WEEK BUT HIGH DEGREE OF UNCERTAINTY IN THE
DETAILS.
BMD
&&
.AVIATION...
FOR THE 06Z TAFS...
LIGHT SNOW WILL CONTINUE OVERNIGHT AND INTO THURSDAY
MORNING...GRADUALLY TAPERING OFF FROM THE NORTH THURSDAY MORNING.
LATEST OBSERVATIONAL TRENDS SUGGEST THAT THE SNOW HAS ERODED THE
LOW LEVEL DRY LAYER AND ANTICIPATE LIGHT SNOW OF VARYING INTENSITY
TO CONTINUE WITH FLUCTUATIONS IN VSBY MOSTLY BETWEEN MVFR AND
IFR...THOUGH BRIEF LIFR VSBY IS POSSIBLE...PARTICULARLY THE MORE
SOUTHERN TERMINALS. AS LOW LEVELS SATURATE...CIGS SHOULD BUILD
DOWN TO IFR BY BY EARLY THURS MORNING AND LIKELY REMAIN IFR
THROUGH THE DAY. COULD SEE SOME FLURRIES LINGER INTO THE
AFTERNOON...PARTICULARLY SOUTH. CIGS LIKELY TO CONTINUE TO
IMPROVE THURSDAY NIGHT.
IZZI
&&
.MARINE...
249 PM CST
WINDS ACROSS LAKE MICHIGAN WILL CONTINUE TO DIMINISH THIS EVENING
AND TONIGHT AS HIGH PRESSURE BUILDS ACROSS THE REGION...THEN EAST TO
SOUTHEASTERLY FLOW WILL RAMP UP STARTING EARLY THURSDAY AS LOW
PRESSURE MAKES ITS WAY ACROSS THE MID MISSISSIPPI VALLEY. WINDS
INCREASE INTO THE 20 TO 25 KT RANGE MAINLY ACROSS THE SOUTH END OF
LAKE MICHIGAN THURSDAY...THEN SHOULD DIMINISH AGAIN THURSDAY NIGHT
AS THE LOW DEPARTS TO THE EAST COAST AND HIGH PRESSURE BUILDS BACK
OVER THE REGION. SOUTHERLY FLOW INCREASES AGAIN ON FRIDAY AHEAD OF A
CLIPPER SYSTEM WHICH IS PROGGED TO TRACK ACROSS SOUTHERN LAKE
MICHIGAN ON SATURDAY. NORTHERLY WINDS BRIEFLY OVERSPREAD LAKE
MICHIGAN AGAIN SATURDAY NIGHT THEN SOUTHERLY WINDS ARE EXPECTED
AGAIN SUNDAY AS BROAD AREA OF LOW PRESSURE DEVELOPS OVER THE PLAINS.
.SYNOPSIS...BROAD HIGH PRESSURE AVERAGING 30.2 INCHES STRETCHES
ALONG THE MISSISSIPPI RIVER VALLEY WHILE LOW PRESSURE OF 29.7 INCHES
IS IN PLACE OVER THE CENTRAL AND NORTHERN PLAINS. THE LOW WILL MOVE
ACROSS THE MID MISSISSIPPI VALLEY MIDDAY THURSDAY THEN SHIFT TO THE
ATLANTIC COAST BY EARLY FRIDAY. ANOTHER RIDGE OF 30.2 INCHES WILL
BUILD ACROSS THE WESTERN GREAT LAKES FRIDAY AND SHIFT TO THE EASTERN
LAKES SATURDAY. LOW PRESSURE OF 29.9 INCHES WILL DROP INTO MINNESOTA
FRIDAY NIGHT AND CROSS SOUTHERN LAKE MICHIGAN SATURDAY. HIGH
PRESSURE OF 30.3 INCHES BUILDS ACROSS THE WESTERN LAKES SATURDAY AND
MOVES TO THE UPPER OHIO VALLEY SUNDAY.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY...ILZ012-ILZ013-ILZ014-ILZ020-ILZ021-
ILZ022-ILZ023 UNTIL 2 PM THURSDAY.
WINTER WEATHER ADVISORY...ILZ008-ILZ010-ILZ011-ILZ019 UNTIL 10
AM THURSDAY.
IN...WINTER WEATHER ADVISORY...INZ001-INZ002 UNTIL 2 PM THURSDAY.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743...6 AM
THURSDAY TO 10 PM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
600 PM EST THU MAR 3 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 315 PM EST THU MAR 3 2016
RAIN AND SNOW WILL END TONIGHT AS A TROUGH MOVES AWAY. A LOW
PRESSURE SYSTEM WILL BRING A RETURN OF PRECIPITATION CHANCES FRIDAY
NIGHT INTO SATURDAY...AND A FRONTAL SYSTEM WILL BRING RAIN NEXT
WEEK. TEMPERATURES WILL WARM TO WELL ABOVE AVERAGE BY NEXT WEEK.
&&
.NEAR TERM.../REST OF THIS AFTERNOON AND TONIGHT/
ISSUED AT 315 PM EST THU MAR 3 2016
SNOW IS HANGING AROUND THE FAR NORTH AND FAR SOUTHEAST WHILE
TEMPERATURES HAVE WARMED ENOUGH FOR RAIN ELSEWHERE. AN INVERTED
TROUGH REMAINS ACROSS THE FAR NORTH.
THIS TROUGH WILL SLIDE SOUTHEAST ACROSS THE FORECAST AREA THIS
EVENING. AN UPPER JET WILL PROVIDE ADDITIONAL SUPPORT. BASED THIS
FORCING WENT LIKELY POPS ACROSS THE NORTH THIRD OR SO OF THE AREA
TAPERING DOWN TO SLIGHT CHANCE FAR SOUTH. FORCING DIMINISHES QUICKLY
OVERNIGHT AS THE SYSTEM EXITS SO LOWERED POPS ACCORDINGLY.
PRECIPITATION TYPE WILL BE TRICKY. AS WARMER AIR HAS SLOWLY WORKED
ITS WAY NORTH...WENT RAIN/SNOW NORTH...WITH MAINLY RAIN SOUTH EARLY
THIS EVENING. AS BOUNDARY LAYER COOLS...PRECIPITATION WILL
CHANGEOVER TO SNOW DURING THE EVENING MOST AREAS.
AFTER SUNSET SNOW MIGHT ACCUMULATE ON GRASSY AREAS NORTH WHERE
TEMPERATURES ARE COOLER...SO WENT A FEW TENTHS OF ACCUMULATION
THERE. NO SNOW ACCUMULATION SOUTH.
MAV MOS LOOKS GOOD FOR LOW TEMPERATURES.
&&
.SHORT TERM.../FRIDAY THROUGH SUNDAY/
ISSUED AT 315 PM EST THU MAR 3 2016
FOCUS IS ON PRECIPITATION CHANCES FRIDAY NIGHT/SATURDAY.
OVERALL...MODELS ARE CLOSE ENOUGH FOR A BLEND UNLESS NOTED BELOW.
CLOUDS WILL DECREASE SOME FRIDAY...BUT THAT WILL NOT LAST LONG AS
MID AND HIGH CLOUDS INCREASE AHEAD OF THE NEXT LOW PRESSURE SYSTEM.
USED A BLEND FOR HIGH TEMPERATURES.
ISENTROPIC LIFT WILL INCREASE AHEAD OF THE WARM FRONT PART OF THE
LOW PRESSURE SYSTEM FRIDAY EVENING. LOOKS LIKE FORCING/MOISTURE
REMAIN LOW ENOUGH TO KEEP THE EVENING DRY...BUT POPS ARE WARRANTED
OVERNIGHT FRIDAY NIGHT AS THE SYSTEM GETS CLOSER.
WITH ISENTROPIC LIFT AND Q-VECTOR CONVERGENCE PROGS BOTH SHOWING
DECENT FORCING...WENT HIGH CHANCE CATEGORY POPS NORTH AND LOWER
CHANCES ELSEWHERE.
PRECIPITATION TYPE WILL BE PROBLEMATIC ONCE AGAIN WITH THERMAL
PROFILES HOVERING AROUND THE FREEZING MARK. WILL GO A MIX OF
RAIN/SNOW SOUTHWEST HALF AND SNOW NORTHEAST FOR NOW. KEPT SNOW
AMOUNTS TO JUST A FEW TENTHS GIVEN THE EXPECTED BORDERLINE
TEMPERATURE PROFILES. /GFS LOOKS TOO STRONG THOUGH WITH ITS FORCING
COMPARED TO OTHERS AND IS SHOWING 3 INCHES OF SNOW. DID NOT GO THAT
HIGH/.
TEMPERATURES WILL WARM DURING SATURDAY FOR ALL PRECIPITATION TO BE
RAIN BY AFTERNOON. HOWEVER FORCING DECREASES DURING THE DAY SO POPS
WILL LOWER FROM WEST TO EAST DURING THE DAY AS WELL.
DRY CONDITIONS WILL RETURN SATURDAY NIGHT INTO SUNDAY AS HIGH
PRESSURE MOVES IN.
STUCK WITH A BLEND OF MODELS FOR TEMPERATURES THROUGH THE SHORT
TERM.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 218 PM EST THU MAR 3 2016
THE INITIALIZATION FROM THE REGIONAL SOFTWARE WILL BE USED WITH HIGH
CONFIDENCE INTO TUESDAY...THEN MODERATE CONFIDENCE.
THERE IS GOOD AGREEMENT BETWEEN DIFFERENT FORECAST METHODS INTO
TUESDAY. INDIANA WEATHER WILL BE DOMINATED BY LARGE POWERFUL SYSTEMS
RELATIVELY EASY TO PREDICT.
AS THE WEEK DRAWS ON THE EUROPEAN MODEL AND THE GFS BECOME MORE
DISTINCT. AT THE SAME TIME THE ENSEMBLE SPREAD WITHIN THE GFS PARENT
MODEL GROWS. THE DIFFERENCES ARENT HUGE BUT INVOLVE FEATURES WHOSE
PRECISE POSITION WILL BE IMPORTANT. A HIGH CONFIDENCE FORECAST FOR
WEDNESDAY AND THURSDAY MAY HAVE TO WAIT UNTIL AT LEAST SATURDAY.
&&
.AVIATION /DISCUSSION FOR 040000Z TAF ISSUANCE/...
ISSUED AT 600 PM EST THU MAR 3 2016
RADAR AND HRRR SUGGEST IND AND LAF WILL SEE A THREAT FOR LIGHT
PRECIPITATION UNTIL NEAR 06Z. THE RAIN SHOULD CHANGE TO SNOW AFTER
01Z. OTHERWISE...PRECIP CHANCES TOO LOW TO MENTION AT BMG AND HUF.
LAMP MOS ALSO STRONGLY SUGGESTS MVFR CEILINGS WILL BECOME IFR BY 03Z
OR EARLIER BEFORE IMPROVING TO MVFR TOWARD 12Z AND VFR AFTER 16Z.
CONFIDENCE IS NOT GREAT ON EXACT TIMING...BUT GOOD REGARDING TRENDS.
WINDS WILL VEER FROM SOUTHEAST TO SOUTHWEST LESS THAN 10 KNOTS
OVERNIGHT AND BECOME LIGHT NORTH OR NORTHEAST AFTER 12Z.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....JK
AVIATION...MK
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
613 PM CST FRI MAR 4 2016
...AVIATION UPDATE...
.SYNOPSIS...
ISSUED AT 254 PM CST FRI MAR 4 2016
18Z SFC DATA HAS A WEAK LOW IN NORTHEAST NORTH DAKOTA. A FRONTAL
BOUNDARY RAN SOUTH FROM THE LOW INTO NORTHWEST KANSAS. DEW POINTS
WERE IN THE TEENS AND 20S ACROSS THE GREAT LAKES WITH 30S ACROSS THE
PLAINS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 254 PM CST FRI MAR 4 2016
AREA RADARS SHOW THE PRECIPITATION IS SLOWLY GETTING BETTER
ORGANIZED ACROSS MINNESOTA. THE PRECIPITATION SEEMS TO LINE UP THE
BEST WITH THE FORCING ON THE 295K THETA SURFACE BASED ON THE RAP
TRENDS. THUS LIGHT RAIN/SPRINKLES SHOULD BEGIN MOVING INTO THE
HIGHWAY 20 CORRIDOR WEST OF DUBUQUE BETWEEN 4 AND 6 PM.
TONIGHT THE RAP SHOWS THE BEST FORCING ON THE 295K THETA SURFACE
RAPIDLY MOVING SOUTHEAST ACROSS THE AREA DURING THE EVENING. THE
STRONGER FORCING IS GENERALLY NORTH OF A WATERLOO IOWA TO GALESBURG
ILLINOIS LINE. THUS THE BETTER POPS WILL BE NORTH OF THIS LINE.
COOLING OF THE ATMOSPHERIC COLUMN WITH SUNSET SHOULD ALLOW A
RAIN/SNOW MIX TO DEVELOP THAT MAY BRIEFLY CHANGE OVER TO ALL SNOW
NORTHEAST OF A DUBUQUE TO STERLING LINE. ANY SNOWFALL AMOUNTS SHOULD
BE WELL UNDER AN INCH.
THE RAPID MOVEMENT OF THE FORCING INDICATES PRECIPITATION WILL END
ACROSS THE AREA BETWEEN 9 PM AND MIDNIGHT. AFTER MIDNIGHT...SOME
LINGERING WEAK FORCING MAY RESULT IN SOME DRIZZLE OR VERY PATCHY
FREEZING DRIZZLE IN THE HIGHWAY 20 CORRIDOR BEFORE ENDING.
ON SATURDAY...BREEZY CONDITIONS WILL INITIALLY BE SEEN ACROSS THE
AREA AS THE STORM SYSTEM MOVES INTO THE EASTERN GREAT LAKES.
OTHERWISE EXPECT QUIET AND DRY CONDITIONS WITH ABOVE NORMAL
TEMPERATURES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 254 PM CST FRI MAR 4 2016
SPRING WEATHER WILL BE IN CONTROL THROUGHOUT THE ENTIRE
EXTENDED...AND SO WILL LOW LEVEL POPS FOR RAIN SHOWERS. I DO NOT
BELIEVE IT WILL RAIN ALL THAT OFTEN IN THE WEEK AHEAD...BUT IN THE
WORLD OF BLENDED MODEL DATA...WE ARE OCCASIONALLY RELEGATED TO
FORECASTING NEARLY CONTINUOUS LOW RAIN CHANCES...AS MODELS OFFER
SLIGHT VARIATIONS ON WHEN RAIN WILL OCCUR. ONE THING IS SOMEWHAT
CERTAIN HERE...IT WILL BE MILD...AND DESPITE ANY CLOUDS THE
SUSTAINED WARM UP WILL NOT BE HELD BACK ANY LOWER THAN THE 50S GIVEN
DEWPOINTS RISING TO THAT LEVEL. RAIN CHANCES APPEAR UNORGANIZED
THROUGH MONDAY AS BROAD WARM ADVECTION SPREADS ACROSS THE REGION.
MODELS HINT AT BETTER COVERAGE OF RAIN SHOWERS MONDAY NIGHT THROUGH
TUESDAY NIGHT...AND POSSIBLY DRY WEATHER AFTER TUESDAY NIGHT.
HOWEVER...THE FRONT FORECAST TO BE JUST SOUTHEAST OF THE REGION
WEDNESDAY AND THURSDAY IS CLOSE ENOUGH THAT SOME RAIN MAY BRUSH THE
SOUTHEAST 1/2 OF THE CWA AT TIMES. THIS IS A VERY LOW CONFIDENCE
RAIN CHANCE...THAT MAY IN THE END BE WELL SOUTHEAST OF THE CWA.
THIS IS GOOD FOR THE SIMPLE FACT THAT WE NEED FURTHER TIME THIS WEEK
TO MELT ANY REMAINING FROST IN THE GROUND PRIOR TO ANY SPRING HEAVY
RAINS. THOSE RAINS APPEAR LIKELY TO BRING FLOODING RAINS TO THE MID
TO LOWER MISSISSIPPI VALLEY THIS WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 610 PM CST FRI MAR 4 2016
BRIEF MVFR CONDITIONS ARE POSSIBLE UNTIL 05/02Z WITH LIGHT RAIN SOUTH
OR SNOW NORTH AS A COOL FRONT PASSES. THEN...SKIES WILL CLEAR BY 05/06Z
WITH VFR CONDITIONS AS WINDS SHIFT FROM THE SOUTH AT 5 TO 10 KTS TO
THE NORTHWEST AT 10 TO 20 KTS THROUGH SATURDAY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...ERVIN
AVIATION...NICHOLS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1020 AM MST THU MAR 3 2016
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 200 AM MST THU MAR 3 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
LARGE SCALE RIDGING IN PLACE ACROSS THE WESTERN US WITH NW FLOW
ACROSS THE ROCKIES INTO THE PLAINS. SHORTWAVE TROUGHS OVER
NORTHEAST KANSAS AND ANOTHER OVER WESTERN NEBRASKA. CONFLUENT FLOW
AND ASSOCIATED SUBSIDENCE IS SPREADING SOUTH INTO NORTHEAST
COLORADO AND NORTHWEST KANSAS AS THE SECOND SHORTWAVE
TRANSITIONS EAST AND SHORTWAVE RIDGING BUILDS TOWARDS THE REGION.
AT THE SURFACE A COLD FRONT HAS COMPLETELY PUSHED THROUGH OUR CWA
WITH HIGH PRESSURE BUILDING SOUTHEAST FROM COLORADO AND THE
NEBRASKA PANHANDLE. THERE IS STILL TIGHT GRADIENT IN PLACE
IMMEDIATELY BEHIND THE FRONT IN OUR EASTERN CWA DUE TO A MESO LOW
APPEARS TO HAVE DEVELOPED IN NORTHCENTRAL/NORTHEAST KANSAS.
TODAY-SATURDAY NIGHT...NORTHWEST TO WESTERLY FLOW WILL CONTINUE
WITH A SERIES OF SHORTWAVE RIDGES AND TROUGHS MOVING ACROSS THE
PLAINS. ANOMALOUSLY HIGH 500MB HEIGHTS REMAIN IN PLACE THROUGH
THESE PERIODS...SO WHILE THERE MAY BE A FEW REINFORCING COLD
FRONTS MOVING INTO OUR CWA...ABOVE NORMAL TEMPERATURES WILL
CONTINUE. MOISTURE PROFILES REMAIN VERY DRY ON ALL GUIDANCE...SO
DESPITE A FRONTAL PASSAGE FRIDAY AND A STRONGER SHORTWAVE
APPROACHING THE REGION SATURDAY NIGHT DRY WEATHER SHOULD CONTINUE.
NAM/SREF ARE ALSO HINTING AT POSSIBLE STRATUS/FOG DEVELOPMENT WITH
MOIST RETURN FLOW SATURDAY NIGHT. BL/SURFACE WINDS AND PROJECTED
SURFACE DEWPOINT DEPRESSIONS APPEAR TO FAVOR STRATUS...AND I
DECIDED AGAINST ADDING FOG MENTION.
A CHANGE I MADE DURING THIS UPDATE WAS TO TREND HIGH TEMPS DOWN A
LITTLE FROM PREVIOUS FORECAST FRIDAY AS FRONT ALREADY APPEARS TO
BE THROUGH MOST OF OUR CWA BY 18Z AND CLOUD COVER MAY BE A BIT
MORE OPAQUE/EXTENSIVE. THIS STILL RESULTS IN ABOVE NORMAL HIGHS
RANGING FROM AROUND 70F IN OUR SOUTH TO MID 60S IN OUR NORTH.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 200 AM MST THU MAR 3 2016
SUNDAY-SUNDAY NIGHT...MID AND HIGH CLOUDS MOVE THROUGH FROM THE
SOUTHWEST DURING THE MORNING WITH DECREASING COVERAGE FROM
SOUTHWEST TO NORTHEAST DURING THE AFTERNOON. SIMILAR
EXPECTATIONS SUNDAY NIGHT...INCREASING CLOUDS THROUGH MIDNIGHT
WITH DECREASING CLOUDS AFTERWORD. THIS IS ALL AHEAD OF AN
APPROACHING UPPER TROUGH. AFTERNOON TEMPERATURES WILL WARM INTO
THE LOW 70S...POSSIBLY A FEW MID 70S IF FULL 850MB MIXING OCCURS.
THIS IS AROUND 20+ DEGREES ABOVE NORMAL. LOW TEMPERATURES ALSO
VERY MILD WITH MID 30S TO MID 40S (WEST TO EAST).
MONDAY-MONDAY NIGHT...SLIGHTLY NEGATIVELY TILTED UPPER TROUGH MOVES
INTO THE AREA FROM THE SOUTHWEST MONDAY AFTERNOON THEN LIFTING OUT
OF THE AREA MONDAY EVENING. EXTENSIVE CLOUDINESS MOVES IN FROM THE
WEST BEHIND THE SYSTEM AND SURFACE COLD FRONT DURING THE
AFTERNOON...SPREADING EAST OVERNIGHT. THERE WILL BE A CHANCE FOR
RAIN SHOWERS ALONG AND BEHIND THE FRONT FROM EARLY TO MID MORNING
THROUGH THE AFTERNOON. AS COLDER AIR MOVES IN DURING THE EVENING
AND OVERNIGHT HOURS SOME LIGHT SNOW IS POSSIBLE. WIDE RANGE IN
AFTERNOON TEMPERATURES WITH LOW TO MID 60S IN FAR EASTERN
COLORADO...LOW 70S FROM NEAR MCCOOK TO LEOTI EAST...ALL DEPENDENT
ON COLD FRONT AND CLOUD ARRIVAL. LOW TEMPERATURES GENERALLY IN THE
LOW 30S TO AROUND 40 (WEST TO EAST).
ANOTHER ITEM THAT WILL NEED TO BE MONITORED WILL BE FIRE WEATHER
THREAT AS HUMIDITY VALUES FALL BELOW 20 PERCENT ACROSS GREELEY AND
WICHITA COUNTIES. WINDS DURING THE TIME OF LOWEST HUMIDITY LOOK TO
BE FROM THE WEST AROUND 15KTS OR SO AND POSSIBLY GUSTY...CREATING A
BORDERLINE CASE FOR A FIRE WEATHER HIGHLIGHT.
TUESDAY-TUESDAY NIGHT...HIGH PRESSURE BUILDS IN FROM THE NORTH
ALLOWING COOLER AIR TO MOVE IN. AFTERNOON TEMPERATURES IN THE
LOW/MID 50S TO LOW 60S LOOKS GOOD PER 850MB TEMPERATURES AND IS
STILL A FEW DEGREES ABOVE NORMAL. LOWS IN THE UPPER 20S TO MID 30S.
EXTENDED PROCEDURE GENERATED SOME SLIGHT CHANCE POPS TUESDAY NIGHT
FOR THE SOUTHEAST 1/2 OR SO OF THE AREA. THERE IS SOME MOISTURE IN
THE 850-500MB LAYER IN THAT AREA BUT IT LOOKS RATHER LIMITED AND
MAY BE WHY MODELS DONT GENERATE ANY MOISTURE FROM IT. WILL KEEP
A MENTION OF IT FOR NOW BUT IT DOESNT LOOK VERY IMPRESSIVE.
WEDNESDAY-WEDNESDAY NIGHT...EXTENDED PROCEDURE POPULATED THE
WEDNESDAY DAY PERIOD WITH SLIGHT CHANCE POPS ALONG THE SAME
SOUTHEAST PORTION OF THE AREA AS TUESDAY NIGHT. AGAIN...RIGHT NOW
MOISTURE DOESNT APPEAR ENOUGH TO WARRANT THE SLIGHT CHANCE POPS.
PER COORDINATION WITH NEIGHBORS IMPACTED BY THE POPS WILL KEEP
IT IN FOR NOW. OTHERWISE SHOULD SEE QUITE A BIT OF SUNSHINE WITH A
MOSTLY CLEAR SKY OVERNIGHT. HIGH TEMPERATURES IN THE LOW TO UPPER
50S WITH LOWS IN THE UPPER 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1017 AM MST THU MAR 3 2016
VFR EXPECTED AT BOTH KGLD AND KMCK THROUGH THE TAF PERIOD DUE TO
AN UPPER LEVEL RIDGE WHICH WILL MOVE OUT OF THE CENTRAL ROCKIES
AND ACROSS THE ADJACENT HIGH PLAINS. BREEZY SURFACE WINDS EARLY
THIS AFTERNOON WILL DIMINISH BY MID AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 200 AM MST THU MAR 3 2016
RH MAY DROP BELOW 20 PERCENT THIS AFTERNOON IN OUR
WEST AND AGAIN FRIDAY AND SATURDAY IN OUR SOUTH. ANY GUSTY WINDS
TODAY WILL BE IN THE MORNING IMMEDIATELY AFTER SUNRISE WITH
DECREASING PRESSURE GRADIENT THROUGH MIDDAY AND LOWER RH VALUES IN
THE AFTERNOON...SO CRITICAL FIRE WEATHER CONDITIONS ARE NOT
EXPECTED. WINDS SHOULD BE STRONG ENOUGH FRIDAY BEHIND THE FRONTAL
PASSAGE...HOWEVER IT DOESNT APPEAR LIKELY THAT 3HR CRITERIA WOULD
BE MET DUE TO MARGINAL RH VALUES OVER MOST OF THE REGION. IT
COULD BE CLOSE IN OUR FAR SOUTH IF TEMPS ARE A BIT WARMER. IF
LOWER TDS ARE ABLE TO MIX SATURDAY WE COULD SEE RED FLAG
CONDITIONS MET OVER WESTERN PORTIONS OF OUR CWA. AT THIS TIME
MOST GUIDANCE IS KEEPING RH JUST ABOVE CRITERIA. THESE PERIODS
WILL NEED TO BE MONITORED...BUT NO WATCHES/WARNINGS ARE PLANNED AT
THIS TIME.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...024
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
411 AM MST THU MAR 3 2016
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 200 AM MST THU MAR 3 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
LARGE SCALE RIDGING IN PLACE ACROSS THE WESTERN US WITH NW FLOW
ACROSS THE ROCKIES INTO THE PLAINS. SHORTWAVE TROUGHS OVER
NORTHEAST KANSAS AND ANOTHER OVER WESTERN NEBRASKA. CONFLUENT FLOW
AND ASSOCIATED SUBSIDENCE IS SPREADING SOUTH INTO NORTHEAST
COLORADO AND NORTHWEST KANSAS AS THE SECOND SHORTWAVE
TRANSITIONS EAST AND SHORTWAVE RIDGING BUILDS TOWARDS THE REGION.
AT THE SURFACE A COLD FRONT HAS COMPLETELY PUSHED THROUGH OUR CWA
WITH HIGH PRESSURE BUILDING SOUTHEAST FROM COLORADO AND THE
NEBRASKA PANHANDLE. THERE IS STILL TIGHT GRADIENT IN PLACE
IMMEDIATELY BEHIND THE FRONT IN OUR EASTERN CWA DUE TO A MESO LOW
APPEARS TO HAVE DEVELOPED IN NORTHCENTRAL/NORTHEAST KANSAS.
TODAY-SATURDAY NIGHT...NORTHWEST TO WESTERLY FLOW WILL CONTINUE
WITH A SERIES OF SHORTWAVE RIDGES AND TROUGHS MOVING ACROSS THE
PLAINS. ANOMALOUSLY HIGH 500MB HEIGHTS REMAIN IN PLACE THROUGH
THESE PERIODS...SO WHILE THERE MAY BE A FEW REINFORCING COLD
FRONTS MOVING INTO OUR CWA...ABOVE NORMAL TEMPERATURES WILL
CONTINUE. MOISTURE PROFILES REMAIN VERY DRY ON ALL GUIDANCE...SO
DESPITE A FRONTAL PASSAGE FRIDAY AND A STRONGER SHORTWAVE
APPROACHING THE REGION SATURDAY NIGHT DRY WEATHER SHOULD CONTINUE.
NAM/SREF ARE ALSO HINTING AT POSSIBLE STRATUS/FOG DEVELOPMENT WITH
MOIST RETURN FLOW SATURDAY NIGHT. BL/SURFACE WINDS AND PROJECTED
SURFACE DEWPOINT DEPRESSIONS APPEAR TO FAVOR STRATUS...AND I
DECIDED AGAINST ADDING FOG MENTION.
A CHANGE I MADE DURING THIS UPDATE WAS TO TREND HIGH TEMPS DOWN A
LITTLE FROM PREVIOUS FORECAST FRIDAY AS FRONT ALREADY APPEARS TO
BE THROUGH MOST OF OUR CWA BY 18Z AND CLOUD COVER MAY BE A BIT
MORE OPAQUE/EXTENSIVE. THIS STILL RESULTS IN ABOVE NORMAL HIGHS
RANGING FROM AROUND 70F IN OUR SOUTH TO MID 60S IN OUR NORTH.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 200 AM MST THU MAR 3 2016
SUNDAY-SUNDAY NIGHT...MID AND HIGH CLOUDS MOVE THROUGH FROM THE
SOUTHWEST DURING THE MORNING WITH DECREASING COVERAGE FROM
SOUTHWEST TO NORTHEAST DURING THE AFTERNOON. SIMILAR
EXPECTATIONS SUNDAY NIGHT...INCREASING CLOUDS THROUGH MIDNIGHT
WITH DECREASING CLOUDS AFTERWORD. THIS IS ALL AHEAD OF AN
APPROACHING UPPER TROUGH. AFTERNOON TEMPERATURES WILL WARM INTO
THE LOW 70S...POSSIBLY A FEW MID 70S IF FULL 850MB MIXING OCCURS.
THIS IS AROUND 20+ DEGREES ABOVE NORMAL. LOW TEMPERATURES ALSO
VERY MILD WITH MID 30S TO MID 40S (WEST TO EAST).
MONDAY-MONDAY NIGHT...SLIGHTLY NEGATIVELY TILTED UPPER TROUGH MOVES
INTO THE AREA FROM THE SOUTHWEST MONDAY AFTERNOON THEN LIFTING OUT
OF THE AREA MONDAY EVENING. EXTENSIVE CLOUDINESS MOVES IN FROM THE
WEST BEHIND THE SYSTEM AND SURFACE COLD FRONT DURING THE
AFTERNOON...SPREADING EAST OVERNIGHT. THERE WILL BE A CHANCE FOR
RAIN SHOWERS ALONG AND BEHIND THE FRONT FROM EARLY TO MID MORNING
THROUGH THE AFTERNOON. AS COLDER AIR MOVES IN DURING THE EVENING
AND OVERNIGHT HOURS SOME LIGHT SNOW IS POSSIBLE. WIDE RANGE IN
AFTERNOON TEMPERATURES WITH LOW TO MID 60S IN FAR EASTERN
COLORADO...LOW 70S FROM NEAR MCCOOK TO LEOTI EAST...ALL DEPENDENT
ON COLD FRONT AND CLOUD ARRIVAL. LOW TEMPERATURES GENERALLY IN THE
LOW 30S TO AROUND 40 (WEST TO EAST).
ANOTHER ITEM THAT WILL NEED TO BE MONITORED WILL BE FIRE WEATHER
THREAT AS HUMIDITY VALUES FALL BELOW 20 PERCENT ACROSS GREELEY AND
WICHITA COUNTIES. WINDS DURING THE TIME OF LOWEST HUMIDITY LOOK TO
BE FROM THE WEST AROUND 15KTS OR SO AND POSSIBLY GUSTY...CREATING A
BORDERLINE CASE FOR A FIRE WEATHER HIGHLITE.
TUESDAY-TUESDAY NIGHT...HIGH PRESSURE BUILDS IN FROM THE NORTH
ALLOWING COOLER AIR TO MOVE IN. AFTERNOON TEMPERATURES IN THE
LOW/MID 50S TO LOW 60S LOOKS GOOD PER 850MB TEMPERATURES AND IS
STILL A FEW DEGREES ABOVE NORMAL. LOWS IN THE UPPER 20S TO MID 30S.
EXTENDED PROCEDURE GENERATED SOME SLIGHT CHANCE POPS TUESDAY NIGHT
FOR THE SOUTHEAST 1/2 OR SO OF THE AREA. THERE IS SOME MOISTURE IN
THE 850-500MB LAYER IN THAT AREA BUT IT LOOKS RATHER LIMITED AND
MAY BE WHY MODELS DONT GENERATE ANY MOISTURE FROM IT. WILL KEEP
A MENTION OF IT FOR NOW BUT IT DOESNT LOOK VERY IMPRESSIVE.
WEDNESDAY-WEDNESDAY NIGHT...EXTENDED PROCEDURE POPULATED THE
WEDNESDAY DAY PERIOD WITH SLIGHT CHANCE POPS ALONG THE SAME
SOUTHEAST PORTION OF THE AREA AS TUESDAY NIGHT. AGAIN...RIGHT NOW
MOISTURE DOESNT APPEAR ENOUGH TO WARRANT THE SLIGHT CHANCE POPS.
PER COORDINATION WITH NEIGHBORS IMPACTED BY THE POPS WILL KEEP
IT IN FOR NOW. OTHERWISE SHOULD SEE QUITE A BIT OF SUNSHINE WITH A
MOSTLY CLEAR SKY OVERNIGHT. HIGH TEMPERATURES IN THE LOW TO UPPER
50S WITH LOWS IN THE UPPER 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 411 AM MST THU MAR 3 2016
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD AT KGLD AND
KMCK TERMINALS THROUGH THE TAF PERIOD. FOG MAY DEVELOP OVER SOUTH
CENTRAL NEBRASKA BY FRIDAY MORNING AS INDICATED BY
SREF/NAM...HOWEVER EVEN IF THIS WERE TO OCCUR IT LOOKS TO REMAIN
EAST OF KMCK. A BRIEF PERIOD OF GUSTY WEST-NORTHWEST WINDS WILL BE
POSSIBLE THIS MORNING AS LLJ TRANSITIONS EAST. BEST CHANCE FOR
GUSTS IS CURRENTLY AT KMCK...THOUGH I COULDNT RULE OUT A FEW GUSTS
15-18KT AT KGLD AS WELL. WINDS SHOULD DECREASE BY MIDDAY WITH
SOUTH TO SOUTHEAST WINDS BELOW 12KT DEVELOPING THIS EVENING AS
SURFACE LOW PRESSURE REDEVELOPS IN EASTERN COLORADO.
&&
.FIRE WEATHER...
ISSUED AT 200 AM MST THU MAR 3 2016
RH MAY DROP BELOW 20 PERCENT THIS AFTERNOON IN OUR
WEST AND AGAIN FRIDAY AND SATURDAY IN OUR SOUTH. ANY GUSTY WINDS
TODAY WILL BE IN THE MORNING IMMEDIATELY AFTER SUNRISE WITH
DECREASING PRESSURE GRADIENT THROUGH MIDDAY AND LOWER RH VALUES IN
THE AFTERNOON...SO CRITICAL FIRE WEATHER CONDITIONS ARE NOT
EXPECTED. WINDS SHOULD BE STRONG ENOUGH FRIDAY BEHIND THE FRONTAL
PASSAGE...HOWEVER IT DOESNT APPEAR LIKELY THAT 3HR CRITERIA WOULD
BE MET DUE TO MARGINAL RH VALUES OVER MOST OF THE REGION. IT
COULD BE CLOSE IN OUR FAR SOUTH IF TEMPS ARE A BIT WARMER. IF
LOWER TDS ARE ABLE TO MIX SATURDAY WE COULD SEE RED FLAG
CONDITIONS MET OVER WESTERN PORTIONS OF OUR CWA. AT THIS TIME
MOST GUIDANCE IS KEEPING RH JUST ABOVE CRITERIA. THESE PERIODS
WILL NEED TO BE MONITORED...BUT NO WATCHES/WARNINGS ARE PLANNED AT
THIS TIME.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...DR
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
510 AM CST THU MAR 3 2016
...Updated Aviation Discussion...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 245 AM CST THU MAR 3 2016
In the wake of an upper level disturbance and associated cold
front. skies will clear out this morning with weak surface high
pressure building into western Kansas today. As the flow becomes
more zonal at mid levels across the Rockies by tonight, surface
troughing will develop in the lee of the Rockies, with a
resumption of south winds. Highs today should be in the lower to
middle 60s, with mainly lower to middle 30s tonight. Temperatures
will be held up tonight by the increasing south winds.
.LONG TERM...(Friday THROUGH Wednesday)
ISSUED AT 245 AM CST THU MAR 3 2016
The mid to upper level pattern will remain fairly zonal through
Saturday across the Rockies and plains before the next upper
level trough amplifies across the Rockies Sunday and ejects into
the plains in a progressive manner by Monday. After a warm day
Friday ahead of a weak cold front with highs in the 70s, highs
Saturday should reach into the mid to upper 60s. Gulf moisture
will surge into the plains ahead of the upper level trough, but
most if not all of the shower and thunderstorm activity is
expected to be off to the east in south central Kansas and points
southward from there from Sunday into Monday. Medicine Lodge and
Pratt will be on the western edge of the small precipitation
chances. After a warm day Sunday with highs in the 70s, Monday
ought to be a mild day as well ahead of the front with downslope
flow and highs in the 70s. Fire weather may be a consideration
Monday if the frontal timing is favorable and stronger southwest
winds and dry air materialize. This system will push a weak cold
front through western Kansas Monday night. Another stronger upper
level storm system is expected to move into the southwestern
United States by Tuesday and into south Texas by Wednesday, which
may be too far south for significant precipitation across western
Kansas. Nevertheless, the gridded forecast does indicated small
chance of showers and thunderstorms Tuesday into Tuesday night
with small chances for showers lingering into Wednesday. Given the
weakness of the aforementioned cold front passing Monday night,
high temperatures are still expected to be in the upper 50s and
lower 60s for Tuesday through Thursday.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z Friday MORNING)
ISSUED AT 508 AM CST THU MAR 3 2016
Gusty northwest winds returning by late morning will fall back
to around 10 knots after 21z Thursday as an area of high pressure
at the surface builds south southeast across western Kansas. After
00z Friday these light winds will back to the south as the surface
high moves into Oklahoma and a trough of low pressure at the
surface develops along the lee of the Rockies. NAM BUFR soundings,
RAP and HRRR indicating VFR conditions over the next 24 hours.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 63 36 73 37 / 0 0 0 0
GCK 63 36 72 35 / 0 0 0 0
EHA 65 40 73 37 / 0 0 0 0
LBL 65 36 75 36 / 0 0 0 0
HYS 60 35 70 36 / 0 0 0 0
P28 65 33 73 40 / 0 0 0 0
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Finch
LONG TERM...Finch
AVIATION...Burgert
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
338 AM CST THU MAR 3 2016
.SHORT TERM...(Today and Tonight)
Issued at 334 AM CST THU MAR 3 2016
Early this morning a shortwave trough was embedded within the
northwesterly flow aloft, with water vapor imagery showing this wave
clipping northeast Kansas. This passing wave helped to push surface
low pressure into the area with a cold front advancing out of the
forecast area. There was enough lift and mid-level moisture from
this frontal passage and shortwave trough to support scattered
showers and isolated thunderstorms last night through early this
morning. Short-range models show these scattered showers gradually
becoming more widely scattered before eventually dissipating around
or shortly after sunrise this morning. Mid-level cloud cover will
stick around through mid morning before quickly scattering out and
making way for mostly sunny skies by this afternoon. Northwesterly
winds will prevail as a result of the early morning frontal passage,
with enough of a pressure gradient in place to support gusts of 20-
30mph late morning into early this afternoon. These northwesterly
winds will support some cold air advection, keeping temperatures
cooler than yesterday with afternoon highs only reaching into the
low/mid 50s. Surface high pressure will track eastward over the
forecast area late this afternoon through tonight, causing winds to
shift to the southeast by Friday morning. The combination of mostly
clear skies and light winds will support decent radiational cooling
and low temperatures dropping into the upper 20s to low 30s tonight.
.LONG TERM...(Friday through Wednesday)
Issued at 334 AM CST THU MAR 3 2016
Friday will see dry conditions with broad upper level ridging in
place. Most guidance seems to have been fairly consistent over the
past few days hinting at the set up for dry conditions to cause
elevated fire weather concerns over northeastern Kansas in the
afternoon Friday as southwest flow at the surface through the mid
levels sets up in response to a lee side trough in place. Although
some high clouds will likely be in place, the atmosphere remains
very dry and will likely mix down some of the dry air to the
surface. As temps rise in the afternoon with dry adibatic
conditions being the rule, expect winds to gust as high as 30mph. As
models tend to do this time of year, the RH values may not have been
low enough. Therefore, lowered dewpoints a degree or two for Friday
afternoon while also increasing the temps by just about the same.
This seems like the likely scenario given the synoptic set up in
place and fairly strong subsidence in place. Saturday remains very
dry, but slightly cooler with a dry cold frontal passage having
taken place. Winds will not be a concern as they should shift to the
northeast and be light enough to not create as elevated of a fire
danger concern.
Into the extended period beginning Sunday afternoon time frame, fire
weather concerns subside as the switch over to possible
thunderstorms takes place with a fairly good amount of WAA beginning
to draw up a good moisture plume for this time of year.
Dewpoints in the mid 50s could be in place by Monday afternoon. The
first shortwave emerging out of the Central Rockies on Sunday ahead
of larger wave trough digging over the Western CONUS into the Desert
Southwest will help to begin to draw this better moisture north from
the Gulf. The ECMWF is a bit more agressive with the overall system
as well as deeper, so have essentially compromised in the long term
with the GFS as there were no major initialization concerns. Into
Sunday afternoon, this lead shortwave will cause isentropic ascent
over southeastern KS and possibly have enough lift and moisture
advection to begin light precip in the form of rain as the
atmosphere continues to saturate. Have kept mention of thunder in
the forecast generally into Monday and Tuesday over northeastern KS
as deep moisture continues to build into the region ahead of a
second major shortwave with a narrow axis of instability working
through the region. While shear profiles increase and a fairly nice
dryline also works toward the region, the atmosphere still appears
to be capped but given the deepening low and continued WAA in place,
perhaps enough factors may come together to erode the cap and cause
a few thunderstorms to form. Whether these would be severe or not
remains to be seen at this point. Again, the better dynamics at
this point seem to be positioned further south over the Southern
Plains and if anything, the trend with models has been pushing
further south with the southern branch of the jet stream.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday)
Issued at 1103 PM CST WED MAR 2 2016
VFR conditions are expect to persist through the night as some dry
air remains in the low levels. The one potential wrench in this
forecast is the NAM showing a brief period of MVFR CIGS around
12Z. The RAP and GFS are a little less obvious in the RH progs and
there aren`t a lot of low clouds upstream across eastern NEB or
western IA. Therefore have maintained a VFR forecast and will
monitor trends. Precip timing is based on the latest HRRR/RAP/NAM
consensus, which fits in fairly well with the prev forecast.
Impact from the light showers at the terminals is expected to be
minor with conditions remaining VFR.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Hennecke
LONG TERM...Drake
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
201 AM MST THU MAR 3 2016
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 200 AM MST THU MAR 3 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
LARGE SCALE RIDGING IN PLACE ACROSS THE WESTERN US WITH NW FLOW
ACROSS THE ROCKIES INTO THE PLAINS. SHORTWAVE TROUGHS OVER
NORTHEAST KANSAS AND ANOTHER OVER WESTERN NEBRASKA. CONFLUENT FLOW
AND ASSOCIATED SUBSIDENCE IS SPREADING SOUTH INTO NORTHEAST
COLORADO AND NORTHWEST KANSAS AS THE SECOND SHORTWAVE
TRANSITIONS EAST AND SHORTWAVE RIDGING BUILDS TOWARDS THE REGION.
AT THE SURFACE A COLD FRONT HAS COMPLETELY PUSHED THROUGH OUR CWA
WITH HIGH PRESSURE BUILDING SOUTHEAST FROM COLORADO AND THE
NEBRASKA PANHANDLE. THERE IS STILL TIGHT GRADIENT IN PLACE
IMMEDIATELY BEHIND THE FRONT IN OUR EASTERN CWA DUE TO A MESO LOW
APPEARS TO HAVE DEVELOPED IN NORTHCENTRAL/NORTHEAST KANSAS.
TODAY-SATURDAY NIGHT...NORTHWEST TO WESTERLY FLOW WILL CONTINUE
WITH A SERIES OF SHORTWAVE RIDGES AND TROUGHS MOVING ACROSS THE
PLAINS. ANOMALOUSLY HIGH 500MB HEIGHTS REMAIN IN PLACE THROUGH
THESE PERIODS...SO WHILE THERE MAY BE A FEW REINFORCING COLD
FRONTS MOVING INTO OUR CWA...ABOVE NORMAL TEMPERATURES WILL
CONTINUE. MOISTURE PROFILES REMAIN VERY DRY ON ALL GUIDANCE...SO
DESPITE A FRONTAL PASSAGE FRIDAY AND A STRONGER SHORTWAVE
APPROACHING THE REGION SATURDAY NIGHT DRY WEATHER SHOULD CONTINUE.
NAM/SREF ARE ALSO HINTING AT POSSIBLE STRATUS/FOG DEVELOPMENT WITH
MOIST RETURN FLOW SATURDAY NIGHT. BL/SURFACE WINDS AND PROJECTED
SURFACE DEWPOINT DEPRESSIONS APPEAR TO FAVOR STRATUS...AND I
DECIDED AGAINST ADDING FOG MENTION.
A CHANGE I MADE DURING THIS UPDATE WAS TO TREND HIGH TEMPS DOWN A
LITTLE FROM PREVIOUS FORECAST FRIDAY AS FRONT ALREADY APPEARS TO
BE THROUGH MOST OF OUR CWA BY 18Z AND CLOUD COVER MAY BE A BIT
MORE OPAQUE/EXTENSIVE. THIS STILL RESULTS IN ABOVE NORMAL HIGHS
RANGING FROM AROUND 70F IN OUR SOUTH TO MID 60S IN OUR NORTH.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 200 AM MST THU MAR 3 2016
SUNDAY-SUNDAY NIGHT...MID AND HIGH CLOUDS MOVE THROUGH FROM THE
SOUTHWEST DURING THE MORNING WITH DECREASING COVERAGE FROM
SOUTHWEST TO NORTHEAST DURING THE AFTERNOON. SIMILAR
EXPECTATIONS SUNDAY NIGHT...INCREASING CLOUDS THROUGH MIDNIGHT
WITH DECREASING CLOUDS AFTERWORD. THIS IS ALL AHEAD OF AN
APPROACHING UPPER TROUGH. AFTERNOON TEMPERATURES WILL WARM INTO
THE LOW 70S...POSSIBLY A FEW MID 70S IF FULL 850MB MIXING OCCURS.
THIS IS AROUND 20+ DEGREES ABOVE NORMAL. LOW TEMPERATURES ALSO
VERY MILD WITH MID 30S TO MID 40S (WEST TO EAST).
MONDAY-MONDAY NIGHT...SLIGHTLY NEGATIVELY TILTED UPPER TROUGH MOVES
INTO THE AREA FROM THE SOUTHWEST MONDAY AFTERNOON THEN LIFTING OUT
OF THE AREA MONDAY EVENING. EXTENSIVE CLOUDINESS MOVES IN FROM THE
WEST BEHIND THE SYSTEM AND SURFACE COLD FRONT DURING THE
AFTERNOON...SPREADING EAST OVERNIGHT. THERE WILL BE A CHANCE FOR
RAIN SHOWERS ALONG AND BEHIND THE FRONT FROM EARLY TO MID MORNING
THROUGH THE AFTERNOON. AS COLDER AIR MOVES IN DURING THE EVENING
AND OVERNIGHT HOURS SOME LIGHT SNOW IS POSSIBLE. WIDE RANGE IN
AFTERNOON TEMPERATURES WITH LOW TO MID 60S IN FAR EASTERN
COLORADO...LOW 70S FROM NEAR MCCOOK TO LEOTI EAST...ALL DEPENDENT
ON COLD FRONT AND CLOUD ARRIVAL. LOW TEMPERATURES GENERALLY IN THE
LOW 30S TO AROUND 40 (WEST TO EAST).
ANOTHER ITEM THAT WILL NEED TO BE MONITORED WILL BE FIRE WEATHER
THREAT AS HUMIDITY VALUES FALL BELOW 20 PERCENT ACROSS GREELEY AND
WICHITA COUNTIES. WINDS DURING THE TIME OF LOWEST HUMIDITY LOOK TO
BE FROM THE WEST AROUND 15KTS OR SO AND POSSIBLY GUSTY...CREATING A
BORDERLINE CASE FOR A FIRE WEATHER HIGHLITE.
TUESDAY-TUESDAY NIGHT...HIGH PRESSURE BUILDS IN FROM THE NORTH
ALLOWING COOLER AIR TO MOVE IN. AFTERNOON TEMPERATURES IN THE
LOW/MID 50S TO LOW 60S LOOKS GOOD PER 850MB TEMPERATURES AND IS
STILL A FEW DEGREES ABOVE NORMAL. LOWS IN THE UPPER 20S TO MID 30S.
EXTENDED PROCEDURE GENERATED SOME SLIGHT CHANCE POPS TUESDAY NIGHT
FOR THE SOUTHEAST 1/2 OR SO OF THE AREA. THERE IS SOME MOISTURE IN
THE 850-500MB LAYER IN THAT AREA BUT IT LOOKS RATHER LIMITED AND
MAY BE WHY MODELS DONT GENERATE ANY MOISTURE FROM IT. WILL KEEP
A MENTION OF IT FOR NOW BUT IT DOESNT LOOK VERY IMPRESSIVE.
WEDNESDAY-WEDNESDAY NIGHT...EXTENDED PROCEDURE POPULATED THE
WEDNESDAY DAY PERIOD WITH SLIGHT CHANCE POPS ALONG THE SAME
SOUTHEAST PORTION OF THE AREA AS TUESDAY NIGHT. AGAIN...RIGHT NOW
MOISTURE DOESNT APPEAR ENOUGH TO WARRANT THE SLIGHT CHANCE POPS.
PER COORDINATION WITH NEIGHBORS IMPACTED BY THE POPS WILL KEEP
IT IN FOR NOW. OTHERWISE SHOULD SEE QUITE A BIT OF SUNSHINE WITH A
MOSTLY CLEAR SKY OVERNIGHT. HIGH TEMPERATURES IN THE LOW TO UPPER
50S WITH LOWS IN THE UPPER 20S TO LOW 30S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1027 PM MST WED MAR 2 2016
VFR CONDITIONS EXPECTED FOR BOTH TAF SITES...WITH FEW-SCT120-250.
WINDS WNW 10-20KTS WITH GUSTS NEAR 30 KTS THRU 22Z...THEN NW
AROUND 10 KTS. BY 02Z FRIDAY...MAINLY SW AROUND 10 KTS.
&&
.FIRE WEATHER...
ISSUED AT 200 AM MST THU MAR 3 2016
RH MAY DROP BELOW 20 PERCENT THIS AFTERNOON IN OUR
WEST AND AGAIN FRIDAY AND SATURDAY IN OUR SOUTH. ANY GUSTY WINDS
TODAY WILL BE IN THE MORNING IMMEDIATELY AFTER SUNRISE WITH
DECREASING PRESSURE GRADIENT THROUGH MIDDAY AND LOWER RH VALUES IN
THE AFTERNOON...SO CRITICAL FIRE WEATHER CONDITIONS ARE NOT
EXPECTED. WINDS SHOULD BE STRONG ENOUGH FRIDAY BEHIND THE FRONTAL
PASSAGE...HOWEVER IT DOESNT APPEAR LIKELY THAT 3HR CRITERIA WOULD
BE MET DUE TO MARGINAL RH VALUES OVER MOST OF THE REGION. IT
COULD BE CLOSE IN OUR FAR SOUTH IF TEMPS ARE A BIT WARMER. IF
LOWER TDS ARE ABLE TO MIX SATURDAY WE COULD SEE RED FLAG
CONDITIONS MET OVER WESTERN PORTIONS OF OUR CWA. AT THIS TIME
MOST GUIDANCE IS KEEPING RH JUST ABOVE CRITERIA. THESE PERIODS
WILL NEED TO BE MONITORED...BUT NO WATCHES/WARNINGS ARE PLANNED AT
THIS TIME.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...JN
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
1103 PM CST WED MAR 2 2016
...AVIATION UPDATE...
.SHORT TERM...(This Evening through Thursday)
Issued at 313 PM CST WED MAR 2 2016
The strong pressure gradient and associated low level jet will relax
this evening causing the winds to diminish. In the meantime deep
mixing has occurred across east central KS, and red flag criteria
has been met. Therefore the red flag warning will continue until 6
pm this evening. Later tonight a few weak shortwaves will track
southeastward across the area. The waves will bring steep mid level
lapse rates and some weak isentropic lift. The steep lapse rates
along with mid level moisture will support elevated cape on the
order of 200 j/kg right ahead of the waves. High based showers with
some embedded thunder could form in north central KS this evening
and move eastward and southeastward overnight. Most of the models
are indicating at least some precip across the area, but these
showers appear scattered in nature and will only produce light
amounts. Especially given the deep mixing and low level dry air in
place.
A cold front will also sweep through the area shifting the winds to
the northwest by sunrise tomorrow. Wind gusts 20 to 30 mph will
occur behind the front and persist through the morning. A second
slightly stronger shortwave will track over the area behind the
initial wave during the late morning. Although this secondary wave
appears to be competing with some isentropic downglide therefore it
may be difficult to form any precip. If any showers were to form it
would most likely take place around sunrise and be more isolated.
Low temperatures tonight will be in the mid 30s to lower 40s, while
highs tomorrow only reach the 50s.
.LONG TERM...(Thursday Night through Wednesday)
Issued at 313 PM CST WED MAR 2 2016
Thursday night through Saturday night, the upper pattern will be
progressive with a southern stream upper ridge moving east across
the southern and central plains on Friday.
A lee surface trough will deepen across the southern high plains and
will cause southerly winds to increase to 15 to 25 MPH across
eastern KS. Highs will warm into the lower to mid 60s Friday
afternoon.
An upper level trough will round the upper ridge axis across
southern Canada, then did southeast across the upper midwest and
Great Lakes states. Low-level cold air advection will cause a
weak cold front to push southward across the CWA Friday night.
North winds of 10 to 20 MPH during the morning will become light
by afternoon. Highs will warm once again into the lower to mid
60s.
Sunday through Wednesday, An intense upper level trough will amplify
across the southwest US and will eventually move east across central
TX on Wednesday. Ahead of this amplified trough a few lead short
wave troughs will lift northeast across the southern and central
plains. The first lead upper trough will lift northeast across KS
and OK on Sunday. Ahead of the trough deeper gulf moisture will
return northward increasing isentropic lift late Saturday night and
Sunday morning and may provide the CWA with a chance for elevated
thunderstorms. The scattered showers and thunderstorms may last
through the day due to increased ascent ahead of the first lead
upper trough and deeper moisture return. Southerly winds will keep
temperatures mild despite cloud cover and chances for showers and
thunderstorms. Highs will reach the lower to mid 60s.
Monday, a more amplified lead trough will lift northeast from the
four corners region into western KS by Monday afternoon. The ECMWF
shows the deeper gulf moisture will be in place ahead of a surface
dryline that will move into central KS. If skies clear and
instability increases ahead of the dryline, then we could see strong
to potentially severe thunderstorms develop across central and north
central KS ahead of the surface dryline. The GFS model veers the
850mb and surface winds ahead of the lead H5 trough, which would
reduce the low-level vertical wind shear. Timing and the
possibility of keeping cloud cover through the day Monday may
negate the potential for severe thunderstorms development across
the CWA. Monday will be warmer with the stronger WAA. Highs on
Monday should reach the lower to mid 70s. If we see more
insolation through the late morning and early afternoon hours,
highs may reach into the upper 70s to near 80 degrees.
Monday night through Tuesday night, The deep upper low across
southern AZ move east into far west TX. A weak cold front that will
move southeast of the CWA will become stationary, while 850mb winds
back to the south and transport deeper moisture north of the surface
boundary. The resulting isentropic lift along with ascent ahead of a
50 to 60 KT H5 jet max will provide periods of showers and
thunderstorms through the period. northwest winds and periods of
showers and thunderstorms will keep temperatures cooler in the lower
to mid 60s.
Wednesday, the deep upper low will slowly move east into west central
TX. A surface low will deepen across southeast OK and move east into
far southern AZ. There may be enough lift due to ascent on the left
exit region of mid level jet combined with isentropic lift for
scattered showers to continue across the CWA. The GFS model is
farther south with the upper low, moving it east across the southern
TX. If the GFS were to verify then the rain chances would end
Tuesday night. Mostly cloudy skies along with low-level cold air
advection will keep highs in the mid to upper 50s.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday)
Issued at 1103 PM CST WED MAR 2 2016
VFR conditions are expect to persist through the night as some dry
air remains in the low levels. The one potential wrench in this
forecast is the NAM showing a brief period of MVFR CIGS around
12Z. The RAP and GFS are a little less obvious in the RH progs and
there aren`t a lot of low clouds upstream across eastern NEB or
western IA. Therefore have maintained a VFR forecast and will
monitor trends. Precip timing is based on the latest HRRR/RAP/NAM
consensus, which fits in fairly well with the prev forecast.
Impact from the light showers at the terminals is expected to be
minor with conditions remaining VFR.
&&
.FIRE WEATHER...
Issued at 313 PM CST WED MAR 2 2016
A Red Flag Warning will continue for the remainder of this
afternoon for portions of eastern Kansas. Relative Humidities have
dropped blow 20 percent along with 30 to 50 MPH wind gusts this
afternoon. Do not burn the remainder of this afternoon!
There will be a very high to extreme rangeland fire index friday
afternoon across the CWA. At this time in the forecast, minimum
RHs will be in the 20 to 30 percent range and southerly wind gust
will be in the 30 MPH range. However, deeper mixing will likely
cause dewpoints to be lower than forecasted and wind gust to be
higher leading to extreme fire danger.
&&
.TOP Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Sanders
LONG TERM...Gargan
AVIATION...Wolters
FIRE WEATHER...Gargan
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1101 PM EST FRI MAR 4 2016
.UPDATE...
ISSUED AT 1058 PM EST FRI MAR 4 2016
THE LOW CLOUDS HAVE BROKEN UP AS THE LOW LEVEL FLOW HAS BECOME
MORE WESTERLY UNDER A WEAK AREA OF RIDGING IN BETWEEN A DEPARTING
SYSTEM AND AN APPROACHING UPPER LEVEL DISTURBANCE AND COLD FRONT.
MODEL TIME HEIGHT SECTIONS SUGGEST BREAKS OR EVEN CLEAR SKIES FOR
THE NEXT 5 HOURS OR SO BEFORE CLOUDS SHOULD THICKEN AND LOWER IN
ADVANCE OF THE COLD FRONT. THIS SHOULD LEAD TO CONTINUED FOG
DEVELOPMENT AND WITH TEMPERATURES NEAR FREEZING PATCHY BLACK ICE
IS A CONCERN ON BRIDGES AND OVERPASSES. ELSEWHERE NORTH OF THE
MTN PARKWAY WHERE SNOW REMAINS ON THE GROUND MELTING ON FRIDAY LED
TO WET ROADS IN SOME LOCATIONS. THIS COULD ALSO LEAD TO SOME
PATCHY BLACK ICE. THE POTENTIAL FOR BLACK ICE HAS BEEN ADDED TO
THE HWO. OTHERWISE...AS FOR THE SYSTEM ARRIVING ON SATURDAY...
SCATTERED SHOWERS POSSIBLY ARRIVING AS EARLY AS 9 AM TO 10 AM EST
PER THE 0Z GFS AND RECENT HRRR RUN...OR LATER PER RAP AND NAM
GUIDANCE. ANY INITIAL PRECIPITATION COULD FALL AS A RAIN AND SNOW
MIX BEFORE WARM ADVECTION THROUGHOUT THE COLUMN IN ADVANCE OF THE
COLD FRONT TURNS ANY PRECIPITATION TO ALL RAIN BY MIDDAY.
UPDATE ISSUED AT 630 PM EST FRI MAR 4 2016
WEAK UPSLOPE FLOW AND MOIST LOW LEVELS IS LEADING TO SOME DRIZZLE
OR VERY LIGHT RAIN...AND OR HIGH ELEVATION FLURRIES ACROSS THE
REGION. THIS SHOULD CONTINUE MAINLY ACROSS THE SOUTHEAST PART OF
THE CWA UNTIL LATE EVENING BEFORE THE LOW LEVEL FLOW BECOMES MORE
WESTERLY AND THE MOISTURE BECOMES MORE SHALLOW. PATCHY FOG SHOULD
ALSO BE COMMONPLACE...BOTH ON THE RIDGES AND IN SOME VALLEY
LOCATIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 345 PM EST FRI MAR 4 2016
LATEST GOES WV IMAGERY SHOWS THE UPPER LEVEL TROUGH AXIS PUSHING
OFF TO THE EAST ALLOWING FOR SOME TEMPORARY DRYING AT MID LEVELS.
AT LOW LEVELS...HOWEVER...MOISTURE AND CLOUDS WILL LIKELY REMAIN
IN PLACE THROUGH THE OVERNIGHT PERIOD...WITH THE POTENTIAL FOR
SOME SCOURING OUT OF THE CLOUDS IN NORTHWESTERN LOCATIONS. A FEW
STRAY SHOWERS ARE ALSO POSSIBLE THIS EVENING. LOWS WILL STAY IN
THE LOWER 30S.
GOES IR IMAGERY SHOWS MID AND HIGH LEVEL CLOUDS STARTING TO
SPREAD INTO THE REGION AHEAD OF THE NEXT SHORTWAVE TROUGH. THIS
TROUGH WILL DROP DOWN FROM THE NORTHERN PLAINS TONIGHT AND PASS
THROUGH EASTERN KENTUCKY DURING THE DAY TOMORROW...PROVIDING
CHANCES OF MAINLY RAIN SHOWERS. DUE TO THE COLDER TEMPERATURES IN
THE NORTHERN COUNTIES...KEPT A BRIEF CHANCE OF A RAIN/SNOW MIX
EARLY ON. RAIN SHOWERS WILL CONTINUE THROUGHOUT THE DAY AND THEN
GRADUALLY PUSH OFF TO THE EAST SATURDAY NIGHT. HIGHS WILL REBOUND
INTO THE UPPER 40S AND LOWER 50S NORTH...WITH SOME MID 50S NOTED
IN THE SOUTHWEST.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 405 PM EST FRI MAR 4 2016
THE MODELS HAVE COME INTO BETTER AGREEMENT ALOFT THROUGH THE
EXTENDED PORTION OF THE FORECAST. THEY ALL DEPICT THE DEPARTURE OF
A SHORTWAVE TROUGH TO THE SOUTHEAST ON SUNDAY WITH RIDGING
BUILDING INTO THE AREA THROUGH MONDAY MORNING. AROUND THIS TIME A
DEEP AND BROAD TROUGH STARTS TO SET UP OVER THE WESTERN UNITED
STATES. THIS TROUGH SETTLES DEEP INTO SOUTHERN CALIFORNIA AND
INTO NORTHERN MEXICO WHILE SENDING SPURS OF ENERGY NORTHEAST INTO
THE SOUTHERN PLAINS. WITH TIME...THE RIDGE BUILDS STRONGER OVER
THE SOUTHERN APPALACHIANS WHILE THE WESTERN TROUGH CLOSES OFF OVER
THE MOUNTAINS OF NORTHWESTERN MEXICO. THIS WILL SET UP BROAD
SOUTHWEST FLOW INTO THE SOUTHERN PLAINS...ONLY SLOWLY MOVING EAST
THROUGH THE MIDDLE OF THE WEEK. ALL THESE FEATURES TIGHTEN UP INTO
WEDNESDAY WITH MORE RIDGING EAST AND TROUGHING TO THE SOUTHWEST.
THROUGH THE DEEP SOUTH SOUTHWEST FLOW...FROM OVER THE WESTERN
GULF...PLENTY OF ENERGY WILL RUN NORTHEAST INTO THE SOUTHERN
PLAINS AND CENTRAL MISSISSIPPI VALLEY INTO THURSDAY. MEANWHILE...
EAST KENTUCKY WILL BE UNDER THE HEAVY INFLUENCE OF STRONG RIDGING
WHOSE CENTER WILL SLOWLY SLIP SOUTH TO SOUTHERN FLORIDA. THE
CUTOFF SOUTHERN LOW WILL START TO GET PICKED UP BY THE NORTHERN
STREAM LATE IN THE WEEK WITH A BETTER CHANCE OF ENERGY SPILLING
INTO KENTUCKY. FOR FRIDAY...THE MODELS ARE IN GENERAL AGREEMENT
WITH THE BROAD LOW MOVING TOWARD THE MISSISSIPPI DELTA WITH
GENERAL SOUTHERLY FLOW CONTINUING OVER KENTUCKY. DUE TO THE DECENT
MODEL AGREEMENT HAVE FAVORED A GENERAL BLEND FOR THE FORECAST
DETAILS.
SENSIBLE WEATHER WILL FEATURE MODERATING TEMPERATURES ON SUNDAY AS
HIGH PRESSURE CROSSES THE OHIO VALLEY AND WEAK LOW PRESSURE MOVES
AWAY FROM THE AREA. FOLLOWING THIS...THE HIGH MOVES TO THE EAST
COAST AND AS IT DOES SO TEMPERATURES WILL REALLY SOAR REACHING WELL
INTO THE MID 60S BY MONDAY AFTERNOON. THIS PATTERN WILL THEN BE
RATHER STEADY STATE THROUGH THE BULK OF THE WEEK. HIGH PRESSURE
WILL KEEP THE RAINS OF THE WEST AT BAY FOR MOST OF THE CWA DURING
THIS TIME. THIS WILL LIKELY SPARE EAST KENTUCKY FROM THE VERY
HEAVY RAINS THAT WILL BE SETTING UP FOR PARTS OF THE SOUTHERN
PLAINS AND INTO THE WESTERN OHIO VALLEY. EVENTUALLY...THOUGH...
THE PATTERN WILL SHIFT EAST ENOUGH THAT SHOWERS AND POSSIBLE
THUNDERSTORMS WILL MOVE INTO OUR AREA FOR WEDNESDAY AND THURSDAY.
ADDITIONAL SHOWERS CAN BE ANTICIPATED FOR FRIDAY...AS WELL. ALSO
THROUGH IT ALL...TEMPERATURES WILL REMAIN WELL ABOVE NORMAL BOTH
FOR HIGHS AND NIGHTTIME LOWS. THE ONLY CONCERN WILL BE FOR PERHAPS
EXCESSIVE RAINS LATE IN THE WEEK AND BEYOND AS THIS AREA OF VERY
MOIST LOW PRESSURE SLOWLY EDGES INTO THE DEEP SOUTH AND TENNESSEE
VALLEY.
ADJUSTED THE GRIDS FROM THE CR INIT MAINLY TO ACCOUNT FOR DECENT
SMALL RIDGE TO VALLEY TEMPERATURE DIFFERENCES SUNDAY THROUGH
WEDNESDAY NIGHTS. ALSO TWEAKED THE POP GRIDS FOR THE LATTER PART
OF THE PERIOD TO SLOW THE ARRIVAL OF THE HIGHER POPS INTO OUR
WESTERN ZONES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 650 PM EST FRI MAR 4 2016
LOW LEVEL MOISTURE REMAINS ALONG WITH WEAK UPSLOPE FLOW AND SOME
FOG AS WELL AS SOME FOG AND DRIZZLE ACROSS THE SOUTHEAST PART OF
THE AREA. CIGS AND OR VIS ARE GENERALLY IFR TO MVFR ACROSS THE
AREA. IMPROVEMENT BACK TO MVFR AND OR VFR IS POSSIBLE OVERNIGHT...
BEFORE THE NEXT SYSTEM BRINGS A THREAT OF SHOWERS AND CONTINUED
MVFR OR A RETURN TO MVFR GENERALLY FROM 14Z THROUGH THE END OF THE
PERIOD. WINDS SHOULD GENERALLY REMAIN AT 10 KT OR LESS THROUGH THE
PERIOD...INITIALLY FROM THE WEST OR NORTHWEST BEFORE BECOMING
SOUTHWEST FROM 9Z ON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...JVM
LONG TERM...GREIF
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
111 AM EST THU MAR 3 2016
.UPDATE...
ISSUED AT 111 AM EST THU MAR 3 2016
THICKER CLOUDS ARE STARTING TO WORK IN FROM THE WEST. TEMPERATURES
HAVE MOSTLY LIKELY BOTTOMED OUT AT THIS POINT...WITH SOME OF THE
SHELTERED VALLEYS REPORTING IN THE LOWER 20S. THE CURRENT FORECAST
HAS THINGS WELL IN HAND...SO WILL ONLY BE FRESHENING UP THE HOURLY
TEMPERATURES...DEW POINTS...AND SKY COVER THROUGH DAWN TO ACCOUNT
FOR THE LATEST TRENDS IN OBSERVATIONS.
UPDATE ISSUED AT 1106 PM EST WED MAR 2 2016
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS
AND TRENDS. FOR NOW...WE HAVE OPTED TO LEAVE THE FORECAST FOR
THURSDAY UNCHANGED FROM THE PREVIOUS UPDATE. THE 0Z GFS IS MORE
CONSISTENT WITH THICKNESSES AND COLUMN TEMPERATURES WHICH WOULD
POINT TOWARD A MIX OF RAIN AND SNOW AT ONSET TO RAIN ON THURSDAY.
IT STILL DOES APPEAR THAT ALL LOCATIONS SHOULD MEASURE ON
THURSDAY. THE 0Z NAM HAS SOME MORE INTENSE PRECIPITATION ON
THURSDAY AFTERNOON AND COOLS THE COLUMN TO NEAR FREEZING WHICH
WOULD POINT TOWARD SOME POTENTIAL FOR ACCUMULATING SNOW.
UPDATE ISSUED AT 658 PM EST WED MAR 2 2016
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT OBSERVATIONS AND
TRENDS. IT WILL BE A WHILE BEFORE THICKER CLOUDS MOVE INTO THE
AREA AND THIS SHOULD SET THE STAGE FOR VALLEY LOCATIONS IN
PARTICULAR TO DROP WELL INTO THE 20S WITH A NOCTURNAL INVERSION
SETTING UP. LOWS FOR DEEPER VALLEYS HAVE BEEN LOWERED ACCORDINGLY.
OTHERWISE...MAX TEMPERATURES FOR TOMORROW SEEMED A BIT TOO HIGH
AND HAVE BEEN LOWERED A BIT CLOSER TO MODEL BLEND NUMBERS. THIS
LED TO A BIT SLOWER ANTICIPATED SFC TEMPERATURE RISE WHEN
PRECIPITATION LIKELY AS SNOW OR A RAIN SNOW MIX SHOULD MOVE INTO
THE AREA FOR THURSDAY...WHICH MIGHT ALLOW FOR A DUSTING TO LESS
THAN A HALF OF ACCUMULATION ON GRASSY AND ELEVATED SURFACES IN
SOME AREAS PARTICULARLY RIDGETOPS. HOWEVER...NO TRAVEL IMPACTS ARE
ANTICIPATED. MOST IF NOT ALL LOCATIONS SHOULD HAVE MEASURABLE
PRECIPITATION ON THURSDAY...SO POPS HAVE BEEN INCREASED TO
CATEGORICAL IN ALL LOCATIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 300 PM EST WED MAR 2 2016
HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE AREA THROUGH THIS
EVENING BUT THEN QUICKLY SHIFT OFF TO THE EAST OVERNIGHT. CLOUDS
WILL BE ON THE INCREASE OVERNIGHT AHEAD OF A CLIPPER LOW PRESSURE
SYSTEM THAT IS PROGGED TO PASS THROUGH THE VICINITY OR JUST SOUTH
OF THE AREA TOMORROW MORNING AND AFTERNOON. PRECIPITATION WILL
LIKELY START OUT AS LIGHT SNOW OR A MIX OF RAIN AND SNOW DURING
THE MORNING BEFORE TRANSITIONING TO A COLD RAIN FOR THE MAJORITY
OF THE EVENT. LITTLE TO NO SNOW ACCUMULATION IS EXPECTED. ALSO DO
NOT EXPECT ANY TRAVEL IMPACTS BECAUSE THE ROAD TEMPERATURES ACROSS
THE AREA ARE CURRENTLY IN THE MID TO UPPER 40S AND ARE NOT
EXPECTED TO DROP TO THE FREEZING MARK. AS THE LOW EXITS THE REGION
LATE THURSDAY NIGHT...RAIN MAY TRANSITION BACK TO A MIX OF
RAIN/SNOW AS THE PRECIPITATION TAPERS OFF. TEMPERATURES WILL
REMAIN ON THE COLD SIDE THROUGH THE SHORT TERM PERIOD WITH TEMPS
TONIGHT DROPPING OFF INTO THE MID AND UPPER 20S. HIGH TEMPERATURES
ON THURSDAY WILL ONLY REACH THE UPPER 30S/LOWER 40S AND LOWS THAT
NIGHT DIPPING BACK INTO THE 30S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 446 PM EST WED MAR 2 2016
A RAPIDLY DEEPENING LOW IS EXPECTED TO BE LOCATED NEAR CAPE
HATTERAS AT THE START OF THE PERIOD...WITH THE JKL FORECAST AREA
ON THE WESTERN FRINGE OF ITS INFLUENCE. A BIT OF LINGERING SNOW OR
RAIN IS POSSIBLE IN THE SOUTHEAST PART OF THE AREA FRIDAY MORNING
BEFORE HIGH PRESSURE BUILDS IN FROM THE NORTHWEST DURING THE DAY.
ITS PRESENCE WILL BE FLEETING...AS IT DEPARTS TO THE SOUTHEAST
AND A WEAK LOW PRESSURE SYSTEM MOVES EAST SOUTHEAST ACROSS THE
CENTRAL APPALACHIANS SATURDAY NIGHT. MODELS HAVE TRENDED DRIER
IN THE JKL FORECAST AREA FOR THIS SYSTEM...WITH MOST OF THE
PRECIP TO OUR NORTH AND NORTHEAST. HAVE TRIMMED POPS TO ONLY
INCLUDE A SLIGHT CHANCE OF PRECIP IN OUR NORTHERN AND EASTERN
COUNTIES. ANOTHER AREA OF HIGH PRESSURE BUILDING IN FROM THE
NORTHWEST WILL BRING DECREASING CLOUDS SUNDAY...AND PARK ITSELF
OFF THE EAST COAST EARLY IN THE WEEK. THIS WILL OCCUR AS A HIGHLY
AMPLIFIED PATTERN SETS UP...WITH AN UPPER LOW SLOWLY MOVING EAST
SOUTHEAST ALONG THE MEXICAN BORDER NEXT WEEK...WHILE STRONG
RIDGING DEVELOPS ALONG THE SOUTHEAST COAST. THE SLOWLY MOVING
REGIME WILL BRING WARM AIR ADVECTION FOR OUR AREA. HOWEVER...WE
WILL NOT HAVE A GOOD TRAJECTORY OFF THE GULF AND SHOULD SEE OUR
LOW LEVEL MOISTURE INCREASE MORE SLOWLY WHEN COMPARED TO AREAS
FURTHER WEST. THIS WOULD HELP TO LIMIT OUR PRECIP POTENTIAL UNTIL
WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 111 AM EST THU MAR 3 2016
CLOUDS WILL THICKEN AND LOWER OVERNIGHT OUT AHEAD OF AN AREA OF
SURFACE LOW PRESSURE THAT PASS BY TO OUR SOUTH DURING THE DAY.
THIS WILL SPREAD A MIX OF LIGHT RAIN/SNOW ACROSS THE AREA BETWEEN
15 AND 18Z...BEFORE TRANSITIONING TO LIGHT RAIN. CEILINGS/VISIBILITIES
WILL LOWER TO MVFR...WITH IFR CEILINGS EXPECTED BY THIS EVENING.
WINDS WILL REMAIN OUT OF THE EAST AND SOUTHEAST AT AROUND 5 KTS
THROUGH THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JVM
LONG TERM...HAL
AVIATION...GEOGERIAN
Area Forecast Discussion
National Weather Service Louisville KY
1249 AM EST THU MAR 3 2016
...Updated Aviation Discussion...
...Forecast Update...
Updated 930 PM EST Wed Mar 3 2016
Temps are close to forecast lows, especially across the Bluegrass
region. Mid-level clouds continue to spread east from the mid
Mississippi Valley as the upper wave digs in, and will put the
brakes on any continued drop in temps. Have included a non-diurnal
temp curve overnight to reflect this.
Low confidence in precip type at onset Thursday morning. With so
much dry air to overcome, we have a sounding that could produce
snow, but it doesn`t seem like we have the forcing to squeeze out a
lot of precip quickly enough. Will not make substantial changes to
precip types until the midnight crew has a look at the 00Z guidance.
What is apparent is that if we end up with widespread precip to go
along with easterly winds, temps will have a really hard time
recovering during the day. Have trended Thu max temps down by a few
degrees, with lower to mid 40s in most locations. Will have a hard
time cracking 40 in the northern Bluegrass.
.SHORT TERM (Now through Thursday Night)...
Issued at 300 PM EST Wed Mar 2 2016
Finally getting some clearing as one system heads off to the east.
In its wake however is another system starting to bring in high
clouds. Low pressure associated with this system will move into
northern MO by daybreak Thursday. Weak isentropic lift over our area
will make for light radar returns by then. Dry low-level air should
weaken/dry out the precip somewhat, but as the day goes along that
dry air should moisten up...especially as the better lift comes
ahead of trough swinging through by late afternoon. By the time the
column moistens, we should just see all rain, but cannot rule out a
few flurries early on in the day. Rainfall totals look to range
from a tenth to two tenths of an inch.
After tonight`s lows around freezing, temperatures during the day
should mostly stay in the 40s, though a few 50s are possible across
south central KY. Will keep in some light precip on the back side of
the system Thursday night and associated cloud cover will keep
temperatures in the low to mid 30s. This precip may see a transition
overnight from rain to snow as temperatures fall, especially over
the north, but still not looking at any significant accumulations.
.LONG TERM (Friday through Wednesday)...
Issued at 320 PM EST Wed Mar 2 2016
Friday we may start off with continued light precip over the
Bluegrass, but will keep pops silent as measurable snow looks
unlikely. Cloud cover should hold on for most of the day, so have
temperatures only in the low to mid 40s. High pressure will move
over the region Friday evening before shift east toward daybreak
Saturday.
Yet another trough will breeze through the region Saturday, bringing
another batch of light precip across the north. Southwesterly winds
ahead of this system will mean highs rising into the 50s. High
pressure will build in quickly behind this front, allowing
temperatures to fall into the 30s at night, close to normal like the
highs Saturday.
Sunday and Monday we should see another warmup, with increasing
southerly winds. Highs by Monday should be well into the 60s. We may
see some warm air advection showers Monday night west of I-65. Then
for Tuesday, the trend in the models has been for our storm chances
to remain west of I-65. That trend would keep us in the warm sector
and allow for high temperatures closer to 70. Then Tuesday night and
Wednesday both deterministic and ensemble solutions drift a front
into the region, perhaps stalling it. Thus will go with higher pops
and above normal temperatures with the muggy airmass. The type of
setup shown by the 12Z GFS and Euro are indicative of those that
bring flood conditions, so will have to watch how the models trend
over the next few days.
&&
.AVIATION (06Z TAF Update)...
Updated at 1245 AM EST Thu Mar 3 2016
The latest 0Z guidance has trended colder and a bit snowier with the
northern stream low pressure system passing through the Ohio Valley
today. VFR conditions can be expected until precip associated with
this weather system arrives. All TAF sites look to begin as a cold
rain between 15-17Z with flight conditions quickly dropping to MVFR.
BWG should stay all rain for the remainder of the day and then
drizzle as precip ends tonight. SDF/LEX will be a bit colder and
precip may change over to snow especially in heavier bursts during
the afternoon hours and as temps cool during the evening hrs so have
added periods of -RASN to these TAFs. IFR conditions should begin
at all TAF sites by this afternoon and persist through the end of
the TAF period. VRB winds early this morning will become
predominantly ESE for much of the TAF period with wind speeds of 6-9
kts common this afternoon.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........RAS
Short Term.....RJS
Long Term......RJS
Aviation.......AMS
Area Forecast Discussion
National Weather Service Louisville KY
1249 AM EST THU MAR 3 2016
...Updated Aviation Discussion...
...Forecast Update...
Updated 930 PM EST Wed Mar 3 2016
Temps are close to forecast lows, especially across the Bluegrass
region. Mid-level clouds continue to spread east from the mid
Mississippi Valley as the upper wave digs in, and will put the
brakes on any continued drop in temps. Have included a non-diurnal
temp curve overnight to reflect this.
Low confidence in precip type at onset Thursday morning. With so
much dry air to overcome, we have a sounding that could produce
snow, but it doesn`t seem like we have the forcing to squeeze out a
lot of precip quickly enough. Will not make substantial changes to
precip types until the midnight crew has a look at the 00Z guidance.
What is apparent is that if we end up with widespread precip to go
along with easterly winds, temps will have a really hard time
recovering during the day. Have trended Thu max temps down by a few
degrees, with lower to mid 40s in most locations. Will have a hard
time cracking 40 in the northern Bluegrass.
.SHORT TERM (Now through Thursday Night)...
Issued at 300 PM EST Wed Mar 2 2016
Finally getting some clearing as one system heads off to the east.
In its wake however is another system starting to bring in high
clouds. Low pressure associated with this system will move into
northern MO by daybreak Thursday. Weak isentropic lift over our area
will make for light radar returns by then. Dry low-level air should
weaken/dry out the precip somewhat, but as the day goes along that
dry air should moisten up...especially as the better lift comes
ahead of trough swinging through by late afternoon. By the time the
column moistens, we should just see all rain, but cannot rule out a
few flurries early on in the day. Rainfall totals look to range
from a tenth to two tenths of an inch.
After tonight`s lows around freezing, temperatures during the day
should mostly stay in the 40s, though a few 50s are possible across
south central KY. Will keep in some light precip on the back side of
the system Thursday night and associated cloud cover will keep
temperatures in the low to mid 30s. This precip may see a transition
overnight from rain to snow as temperatures fall, especially over
the north, but still not looking at any significant accumulations.
.LONG TERM (Friday through Wednesday)...
Issued at 320 PM EST Wed Mar 2 2016
Friday we may start off with continued light precip over the
Bluegrass, but will keep pops silent as measurable snow looks
unlikely. Cloud cover should hold on for most of the day, so have
temperatures only in the low to mid 40s. High pressure will move
over the region Friday evening before shift east toward daybreak
Saturday.
Yet another trough will breeze through the region Saturday, bringing
another batch of light precip across the north. Southwesterly winds
ahead of this system will mean highs rising into the 50s. High
pressure will build in quickly behind this front, allowing
temperatures to fall into the 30s at night, close to normal like the
highs Saturday.
Sunday and Monday we should see another warmup, with increasing
southerly winds. Highs by Monday should be well into the 60s. We may
see some warm air advection showers Monday night west of I-65. Then
for Tuesday, the trend in the models has been for our storm chances
to remain west of I-65. That trend would keep us in the warm sector
and allow for high temperatures closer to 70. Then Tuesday night and
Wednesday both deterministic and ensemble solutions drift a front
into the region, perhaps stalling it. Thus will go with higher pops
and above normal temperatures with the muggy airmass. The type of
setup shown by the 12Z GFS and Euro are indicative of those that
bring flood conditions, so will have to watch how the models trend
over the next few days.
&&
.AVIATION (06Z TAF Update)...
Updated at 1245 AM EST Thu Mar 3 2016
The latest 0Z guidance has trended colder and a bit snowier with the
northern stream low pressure system passing through the Ohio Valley
today. VFR conditions can be expected until precip associated with
this weather system arrives. All TAF sites look to begin as a cold
rain between 15-17Z with flight conditions quickly dropping to MVFR.
BWG should stay all rain for the remainder of the day and then
drizzle as precip ends tonight. SDF/LEX will be a bit colder and
precip may change over to snow especially in heavier bursts during
the afternoon hours and as temps cool during the evening hrs so have
added periods of -RASN to these TAFs. IFR conditions should begin
at all TAF sites by this afternoon and persist through the end of
the TAF period. VRB winds early this morning will become
predominantly ESE for much of the TAF period with wind speeds of 6-9
kts common this afternoon.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........RAS
Short Term.....RJS
Long Term......RJS
Aviation.......AMS
Area Forecast Discussion
National Weather Service Louisville KY
1249 AM EST THU MAR 3 2016
...Updated Aviation Discussion...
...Forecast Update...
Updated 930 PM EST Wed Mar 3 2016
Temps are close to forecast lows, especially across the Bluegrass
region. Mid-level clouds continue to spread east from the mid
Mississippi Valley as the upper wave digs in, and will put the
brakes on any continued drop in temps. Have included a non-diurnal
temp curve overnight to reflect this.
Low confidence in precip type at onset Thursday morning. With so
much dry air to overcome, we have a sounding that could produce
snow, but it doesn`t seem like we have the forcing to squeeze out a
lot of precip quickly enough. Will not make substantial changes to
precip types until the midnight crew has a look at the 00Z guidance.
What is apparent is that if we end up with widespread precip to go
along with easterly winds, temps will have a really hard time
recovering during the day. Have trended Thu max temps down by a few
degrees, with lower to mid 40s in most locations. Will have a hard
time cracking 40 in the northern Bluegrass.
.SHORT TERM (Now through Thursday Night)...
Issued at 300 PM EST Wed Mar 2 2016
Finally getting some clearing as one system heads off to the east.
In its wake however is another system starting to bring in high
clouds. Low pressure associated with this system will move into
northern MO by daybreak Thursday. Weak isentropic lift over our area
will make for light radar returns by then. Dry low-level air should
weaken/dry out the precip somewhat, but as the day goes along that
dry air should moisten up...especially as the better lift comes
ahead of trough swinging through by late afternoon. By the time the
column moistens, we should just see all rain, but cannot rule out a
few flurries early on in the day. Rainfall totals look to range
from a tenth to two tenths of an inch.
After tonight`s lows around freezing, temperatures during the day
should mostly stay in the 40s, though a few 50s are possible across
south central KY. Will keep in some light precip on the back side of
the system Thursday night and associated cloud cover will keep
temperatures in the low to mid 30s. This precip may see a transition
overnight from rain to snow as temperatures fall, especially over
the north, but still not looking at any significant accumulations.
.LONG TERM (Friday through Wednesday)...
Issued at 320 PM EST Wed Mar 2 2016
Friday we may start off with continued light precip over the
Bluegrass, but will keep pops silent as measurable snow looks
unlikely. Cloud cover should hold on for most of the day, so have
temperatures only in the low to mid 40s. High pressure will move
over the region Friday evening before shift east toward daybreak
Saturday.
Yet another trough will breeze through the region Saturday, bringing
another batch of light precip across the north. Southwesterly winds
ahead of this system will mean highs rising into the 50s. High
pressure will build in quickly behind this front, allowing
temperatures to fall into the 30s at night, close to normal like the
highs Saturday.
Sunday and Monday we should see another warmup, with increasing
southerly winds. Highs by Monday should be well into the 60s. We may
see some warm air advection showers Monday night west of I-65. Then
for Tuesday, the trend in the models has been for our storm chances
to remain west of I-65. That trend would keep us in the warm sector
and allow for high temperatures closer to 70. Then Tuesday night and
Wednesday both deterministic and ensemble solutions drift a front
into the region, perhaps stalling it. Thus will go with higher pops
and above normal temperatures with the muggy airmass. The type of
setup shown by the 12Z GFS and Euro are indicative of those that
bring flood conditions, so will have to watch how the models trend
over the next few days.
&&
.AVIATION (06Z TAF Update)...
Updated at 1245 AM EST Thu Mar 3 2016
The latest 0Z guidance has trended colder and a bit snowier with the
northern stream low pressure system passing through the Ohio Valley
today. VFR conditions can be expected until precip associated with
this weather system arrives. All TAF sites look to begin as a cold
rain between 15-17Z with flight conditions quickly dropping to MVFR.
BWG should stay all rain for the remainder of the day and then
drizzle as precip ends tonight. SDF/LEX will be a bit colder and
precip may change over to snow especially in heavier bursts during
the afternoon hours and as temps cool during the evening hrs so have
added periods of -RASN to these TAFs. IFR conditions should begin
at all TAF sites by this afternoon and persist through the end of
the TAF period. VRB winds early this morning will become
predominantly ESE for much of the TAF period with wind speeds of 6-9
kts common this afternoon.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........RAS
Short Term.....RJS
Long Term......RJS
Aviation.......AMS
Area Forecast Discussion
National Weather Service Paducah KY
1106 PM CST WED MAR 2 2016
.UPDATE...
Issued at 1106 PM CST WED MAR 2 2016
Updated aviation section for 06z taf issuance
UPDATE issued at 934 PM CST WED MAR 2 2016
Starting to see some decent signal for a drier forecast overnight
and Thursday over the north/northeast portions of the area. The
00Z NAM keeps the entire area dry through 12Z, and then spreads
precipitation eastward through southeast Missouri and much of west
Kentucky. The latest RAP and HRRR runs also have trended this way.
Decided to trend drier over the Evansville Tri State and the
Pennyrile region of west Kentucky through 12Z, and then blend with
the likely to categorical PoPs throughout the area later in the
day. Also trended warmer with overnight temperatures in the east,
with most places not likely to drop much from current levels,
unless there is enough precipitation to wet bulb which is unlikely.
&&
.SHORT TERM...(This evening through Friday night)
Issued at 258 PM CST WED MAR 2 2016
Clouds are starting to increase now, and will be working down from
the mid levels overnight as showers set in tmrw. Instability
parameters keep thunder chances just outside (mainly south) of PAH
FA thru the event, but with the surface/upper Low tracks across
the FA, wouldnt be shocked to see an isolated stroke. No consensus
for adding though, so went just showers for the event.
The system is positively tilted, filling, and weakening as it
moves across the FA. Good moisture influx and deep column moisture
advection means main impact will be qpf, with low end totals of
1/4 to 1/2" expected, and high end amounts approaching 1" not out
of the realm of possibility.
While a lingering sprinkle or two is not of the question, the
wetting rain event is over tmrw. Moisture does take awhile to
scour, so clouds could be stubborn/hang into Friday, particularly
east, before clearing out in earnest.
.LONG TERM...(Saturday through Wednesday)
Issued at 258 PM CST WED MAR 2 2016
The more significant weather during the extended period will be
focused toward the last day of the seven day forecast period
(Tuesday).
Through at least Sunday, the WFO PAH forecast area is expected to
gradually shift from northwest flow ahead of slowly moving westward
tilted upper level high pressure ridge to southerly flow as this
ridge axis moves over the area during the day on Sunday.
The net effect for the weekend will be dry weather and warmer
temperatures.
From Sunday night onward, both ensemble and deterministic guidance
carve out a convoluted mean trough over the western 1/2 of the U.S.
with successive shortwaves deepening the trough. There is a wide
variability in the exact location/orientation of the trough via the
12z Wednesday deterministic GFS/ECMWF, but both seem to show an
initial progressive trough over the northern Mexico and the desert
Southwest U.S., before becoming meridional by early Wednesday.
Given the open and strong fetch of Gulf of Mexico moisture and the
persistent nature of the baroclinic gradient on the east side of
this trough, anticipate isentropically lifted shower activity will
dominate parts of Southeast Missouri and Southern Illinois, as early
as Sunday night and persisting through Monday night.
Initially, it looks like Tuesday into Wednesday of next week (just
beyond the seven day forecast period) will be interesting. Model
Analogs from the GFS Ensemble suggest that there will be around a
50% probability of close to one half inch of rain with a 30%
probability in excess of one inch, mainly over Southeast Missouri and
part of Southwest Illinois. NCEP modeling center QPF plumes suggest
an average 2" precipitation between 12z Tuesday to 12z Wednesday of
next week centered near Paducah. An Atmospheric River forecast
forecast prog (presented by our SOO), suggests that deep moisture
will be working up the Mississippi River next week. The only caveat
to a heavy rain setup for part of the WFO PAH forecast area will be
intervening convective development that could occur over the Lower
Mississippi Valley, impacting parts of Mississippi, Alabama, and
Tennessee.
Regardless, it will be worth watching and planning for heavy rain
potential and possible severe weather early next week, beginning
with the Monday/Tuesday time frame. SPC is already monitoring the
potential for severe weather for early next week.
&&
.AVIATION...
Issued at 1106 PM CST WED MAR 2 2016
Widespread mid clouds around 10k feet will continue through the
night, possibly producing some virga. Unusually dry southeast winds
will evaporate the precip before it reaches the ground. Between 12z
and 18z Thursday, the low levels will moisten up as heavier
precipitation starts falling through the column. Cigs and vsbys will
lower to mvfr. A period of ifr conditions is likely for at least a
few hours where the heavier precip occurs. The 06z tafs will
forecast ifr at kcgi/kpah based on heavier precip rates in those
areas.
&&
.PAH Watches/Warnings/Advisories...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...DRS
AVIATION...MY
AREA FORECAST DISCUSSION
NWS GRAY ME
934 PM EST FRI MAR 4 2016
.SYNOPSIS...
LOW PRESSURE WILL PASS WELL OFF THE COAST TONIGHT. HIGH PRESSURE
WILL START TO BUILD OVER THE REGION THROUGHOUT THE WEEKEND AND
INTO NEXT WEEK. AS HIGH PRESSURE DOMINATES OVER MUCH OF THE EAST
COAST NEXT WEEK...SOUTHWESTERLY FLOW WILL SET UP OVER NEW ENGLAND.
THIS WILL ALLOW MUCH WARMER AIR TO STREAM INTO THE AREA. BY
MIDWEEK TEMPERATURES ARE EXPECTED TO BE WELL ABOVE NORMAL. A WEAK
COLD FRONT WILL TRY TO CROSS THE AREA ON THURSDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
UPDATE...
HAVE UPDATED THE GRIDS BASED ON CURRENT OBSERVATIONS...RADAR
TRENDS AND MESOSCALE MODEL DATA. LIGHT SNOW SHOWERS CONTINUE TO
FALL OVER SOUTHWEST MAINE AND SOUTHEAST NEW HAMPSHIRE...HOWEVER
MANY OF THE RETURNS DEPICTED ON RADAR ARE NOT REACHING THE GROUND
AS MOISTURE IS LACKING IN THE LOWEST LEVELS. WILL TAKE DOWN THE
WINTER WEATHER ADVISORIES A FEW HOURS EARLY AS LITTLE
PRECIPITATION IS ACCUMULATING IN ROCKINGHAM COUNTY.
HAVE ADJUSTED POPS...TEMPERATURES AND CLOUD GRIDS AS WELL.
PREV DISC...
BIGGEST FORECAST PROBLEM IS GOING TO BE THE OCEAN
EFFECT SNOW THAT IS CONTINUING OVER SOUTHERN NEW HAMPSHIRE. WHILE
THERE IS SOME LIGHT SNOW FALLING OVER PORTIONS OF COASTAL MAINE AS
WELL...ROCKINGHAM COUNTY IN NEW HAMPSHIRE IS SEEING THE LIONS
SHARE OF THE PRECIPITATION. BOTH THE RAP AND THE NAM12 HAVE
STARTED TO PICK UP ON THIS FEATURE AND THE HRRR IS STARTING TO
FALL IN LINE ALSO. IT LOOKS AS THOUGH THE SNOW COULD CONTINUE
THROUGH THE AFTERNOON COMMUTE AND INTO THE EVENING HOURS. BECAUSE
OF THIS...WE HAVE PULLED THE TRIGGER ON A WINTER WEATHER ADVISORY
FOR ROCKINGHAM COUNTY.
&&
.SHORT TERM /SATURDAY NIGHT/...
AS THE COASTAL LOW PASSES WELL OFF TO THE EAST OF THE REGION
EXPECT COOL HIGH PRESSURE TO BUILD OVER THE AREA WITH NORTHERLY
FLOW. SKIES SHOULD CLEAR OUT QUICKLY ON SATURDAY WITH PLENTY OF
SUNSHINE AS HIGHS CLIMB INTO THE UPPER 30S.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH IMPACT WX: NONE ANTICIPATED.
LARGE SCALE HEMISPHERIC FLOW AT 500 MB AS POLAR VORTEX OVER NRN
CANADA BEGINS TO SEND PIECES OFF TO THE EAST AND EVENTUALLY
BREAKS DOWN THE BLOCKING OVER THE NRN ATLANTIC...WHILE A SERIES OF
LOWS DEEPEN OVER THE ERN PACIFIC AND BREAK DOWN THE RIDGING OVER
THE WEST COAST. THIS WILL ALLOW FOR A TREND TOWARD RIDGING OVER
THE ERN 2/3 OF THE CONUS AND THE WRN AND GENERALLY DRIER CONDS /NO
MAJOR STORMS/ AND SIGNIFICANTLY WARMER CONDS AS WELL.
FROM A SENSIBLE WX PERSPECTIVE...SUNDAY STARTS WITH A WEAK 500 MB
TROUGH MOVING THROUGH WHICH WILL PRODUCE A FAIR AMT OF MID-HIGH
CLOUDS...BUT NOT MUCH ELSE. THE RIDGE STARTS BUILDING IN SUN
NIGHT...BUT ANOTHER WEAK WAVE DROPS OUT OF THE POLAR VORTEX AND
CLIPS THE NE ZONES MONDAY AND COULD SET OFF A FEW SHSN OR RA IN
THE MTNS MONDAY. RIDGING ALOFT THE MOVES IN FOR TUE-WED WITH SFC
RIDGE BUILDING TO OUR S. EURO AND GFS DOW PASS A 500MB OVER OR
JUST TO OUR N LATE WED INTO THU NIGHT. MODELS DIVERGE QUITE A BIT
AT THIS POINT, WITH THE GFS PUSHING MOISTURE OVER THE TOP OF THE
RIDGE AROUND THU...AS A COLD FRONT STALLS OVER NEW ENGLAND. THE
EURO TIMING IS REVERSED WITH THE COLD FRONT BEING PUSHED DOWN THU
AND AND STALLING S OF THE CWA...AS A WAVE MOVES ALONG IT THU
NIGHT. EITHER WAY...QPF NOT IMPRESSIVE ATTM...AND WILL LIKELY FALL
AS RAIN. THE MODEL BLEND OF POPS GENERALLY KEEP THEM IN THE SLT
CHC TO LOW CHC RANGE IN THE WED-THU NIGHT PERIOD.
TEMPS START AROUND NORMAL ON SUNDAY...AROUND 30 IN THE N TO AROUND
40 IN THE S. MON WILL SEE TEMPS JUMP UP SIGNIFICANTLY WITH HIGHS
FROM 40 TO 50...AND THE WILL INCREASE SEVERAL DEGREES EACH ON TUE
AND WED WITH WED HIGHS WELL ABOVE NORMAL...RANGING FROM THE LOW TO
MID 50S IN THE N TO 60-65 IN THE S. THE PRESENCE OF THE FRONTAL
BOUNDARY AND LOTS OF CLOUDS WILL SCALE BACK TEMPS ON THU AND
FRI...BUT THEY WILL STILL REMAIN ABOUT 10F ABV NORMAL.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SAT NIGHT/...EXPECT IFR/MVFR CONDITIONS IN
SNOW AT KCON...KPWM...KPSM AND KMHT. OCEAN EFFECT SNOW IS EXPECTED
TO CONTINUE INTO THE EVENING HOURS. ONCE SNOW ENDS EXPECT ALL
LOCATIONS TO GO VFR THROUGH SATURDAY NIGHT.
LONG TERM...MAINLY VFR SUN-WED.
&&
.MARINE...
SHORT TERM /THROUGH SAT NIGHT/...AS LOW PRESSURE PASSES TO THE
EAST OF THE REGION EXPECT WINDS TO PICK UP OVER THE WATERS. IT
SHOULD BE A FAIRLY SHORT LIVED EVENT WITH WINDS TONIGHT AND
TOMORROW. ONCE THE LOW MOVES AWAY FROM THE REGION...HIGH PRESSURE
BUILDS AS WINDS DECREASE.
LONG TERM...SCA POSSIBLE ON MONDAY AS WINDS SW WINDS SURGE AHEAD
OF A FRONT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST SATURDAY FOR ANZ151-153.
GALE WARNING UNTIL NOON EST SATURDAY FOR ANZ150-152-154.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
648 PM EST FRI MAR 4 2016
.SYNOPSIS...
LOW PRESSURE WILL PASS WELL OFF THE COAST TONIGHT. HIGH PRESSURE
WILL START TO BUILD OVER THE REGION THROUGHOUT THE WEEKEND AND
INTO NEXT WEEK. AS HIGH PRESSURE DOMINATES OVER MUCH OF THE EAST
COAST NEXT WEEK...SOUTHWESTERLY FLOW WILL SET UP OVER NEW ENGLAND.
THIS WILL ALLOW MUCH WARMER AIR TO STREAM INTO THE AREA. BY
MIDWEEK TEMPERATURES ARE EXPECTED TO BE WELL ABOVE NORMAL. A WEAK
COLD FRONT WILL TRY TO CROSS THE AREA ON THURSDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
UPDATE...
HAVE UPDATED THE GRIDS BASED ON CURRENT OBSERVATIONS...RADAR
TRENDS AND MESOSCALE MODEL DATA. LIGHT SNOWS CONTINUE...MAINLY
ALONG AND NEAR THE COASTLINE. UP TO 3 INCHES OF OCEAN ENHANCED
SNOW FELL IN ROCKINGHAM COUNTY TODAY. SNOW IN THIS AREA HAS BEEN
INTERMITTENT...HOWEVER WILL LEAVE UP WINTER WEATHER ADVISORY FOR A
FEW MORE HOURS UNTIL THE BANDS SHIFT OUT TO SEA.
HAVE ADJUSTED POPS...TEMPERATURES AND CLOUD GRIDS AS WELL.
PREV DISC...
BIGGEST FORECAST PROBLEM IS GOING TO BE THE OCEAN
EFFECT SNOW THAT IS CONTINUING OVER SOUTHERN NEW HAMPSHIRE. WHILE
THERE IS SOME LIGHT SNOW FALLING OVER PORTIONS OF COASTAL MAINE AS
WELL...ROCKINGHAM COUNTY IN NEW HAMPSHIRE IS SEEING THE LIONS
SHARE OF THE PRECIPITATION. BOTH THE RAP AND THE NAM12 HAVE
STARTED TO PICK UP ON THIS FEATURE AND THE HRRR IS STARTING TO
FALL IN LINE ALSO. IT LOOKS AS THOUGH THE SNOW COULD CONTINUE
THROUGH THE AFTERNOON COMMUTE AND INTO THE EVENING HOURS. BECAUSE
OF THIS...WE HAVE PULLED THE TRIGGER ON A WINTER WEATHER ADVISORY
FOR ROCKINGHAM COUNTY.
&&
.SHORT TERM /SATURDAY NIGHT/...
AS THE COASTAL LOW PASSES WELL OFF TO THE EAST OF THE REGION
EXPECT COOL HIGH PRESSURE TO BUILD OVER THE AREA WITH NORTHERLY
FLOW. SKIES SHOULD CLEAR OUT QUICKLY ON SATURDAY WITH PLENTY OF
SUNSHINE AS HIGHS CLIMB INTO THE UPPER 30S.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH IMPACT WX: NONE ANTICIPATED.
LARGE SCALE HEMISPHERIC FLOW AT 500 MB AS POLAR VORTEX OVER NRN
CANADA BEGINS TO SEND PIECES OFF TO THE EAST AND EVENTUALLY
BREAKS DOWN THE BLOCKING OVER THE NRN ATLANTIC...WHILE A SERIES OF
LOWS DEEPEN OVER THE ERN PACIFIC AND BREAK DOWN THE RIDGING OVER
THE WEST COAST. THIS WILL ALLOW FOR A TREND TOWARD RIDGING OVER
THE ERN 2/3 OF THE CONUS AND THE WRN AND GENERALLY DRIER CONDS /NO
MAJOR STORMS/ AND SIGNIFICANTLY WARMER CONDS AS WELL.
FROM A SENSIBLE WX PERSPECTIVE...SUNDAY STARTS WITH A WEAK 500 MB
TROUGH MOVING THROUGH WHICH WILL PRODUCE A FAIR AMT OF MID-HIGH
CLOUDS...BUT NOT MUCH ELSE. THE RIDGE STARTS BUILDING IN SUN
NIGHT...BUT ANOTHER WEAK WAVE DROPS OUT OF THE POLAR VORTEX AND
CLIPS THE NE ZONES MONDAY AND COULD SET OFF A FEW SHSN OR RA IN
THE MTNS MONDAY. RIDGING ALOFT THE MOVES IN FOR TUE-WED WITH SFC
RIDGE BUILDING TO OUR S. EURO AND GFS DOW PASS A 500MB OVER OR
JUST TO OUR N LATE WED INTO THU NIGHT. MODELS DIVERGE QUITE A BIT
AT THIS POINT, WITH THE GFS PUSHING MOISTURE OVER THE TOP OF THE
RIDGE AROUND THU...AS A COLD FRONT STALLS OVER NEW ENGLAND. THE
EURO TIMING IS REVERSED WITH THE COLD FRONT BEING PUSHED DOWN THU
AND AND STALLING S OF THE CWA...AS A WAVE MOVES ALONG IT THU
NIGHT. EITHER WAY...QPF NOT IMPRESSIVE ATTM...AND WILL LIKELY FALL
AS RAIN. THE MODEL BLEND OF POPS GENERALLY KEEP THEM IN THE SLT
CHC TO LOW CHC RANGE IN THE WED-THU NIGHT PERIOD.
TEMPS START AROUND NORMAL ON SUNDAY...AROUND 30 IN THE N TO AROUND
40 IN THE S. MON WILL SEE TEMPS JUMP UP SIGNIFICANTLY WITH HIGHS
FROM 40 TO 50...AND THE WILL INCREASE SEVERAL DEGREES EACH ON TUE
AND WED WITH WED HIGHS WELL ABOVE NORMAL...RANGING FROM THE LOW TO
MID 50S IN THE N TO 60-65 IN THE S. THE PRESENCE OF THE FRONTAL
BOUNDARY AND LOTS OF CLOUDS WILL SCALE BACK TEMPS ON THU AND
FRI...BUT THEY WILL STILL REMAIN ABOUT 10F ABV NORMAL.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SAT NIGHT/...EXPECT IFR/MVFR CONDITIONS IN
SNOW AT KCON...KPWM...KPSM AND KMHT. OCEAN EFFECT SNOW IS EXPECTED
TO CONTINUE INTO THE EVENING HOURS. ONCE SNOW ENDS EXPECT ALL
LOCATIONS TO GO VFR THROUGH SATURDAY NIGHT.
LONG TERM...MAINLY VFR SUN-WED.
&&
.MARINE...
SHORT TERM /THROUGH SAT NIGHT/...AS LOW PRESSURE PASSES TO THE
EAST OF THE REGION EXPECT WINDS TO PICK UP OVER THE WATERS. IT
SHOULD BE A FAIRLY SHORT LIVED EVENT WITH WINDS TONIGHT AND
TOMORROW. ONCE THE LOW MOVES AWAY FROM THE REGION...HIGH PRESSURE
BUILDS AS WINDS DECREASE.
LONG TERM...SCA POSSIBLE ON MONDAY AS WINDS SW WINDS SURGE AHEAD
OF A FRONT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NHZ013-
014.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST SATURDAY FOR ANZ151-153.
GALE WARNING UNTIL NOON EST SATURDAY FOR ANZ150-152-154.
&&
$$
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1201 PM EST THU MAR 3 2016
.AVIATION...
SURFACE HIGH PRESSURE AND LOW LEVEL DRY AIR OVER MUCH OF LOWER
MICHIGAN HAS BEEN STUBBORN THUS FAR...BUT STILL EXPECT SNOW TO
OVERSPREAD SOUTHEAST MICHIGAN SOUTH OF I-69 CORRIDOR THIS
AFTERNOON...CONTINUING INTO EVENING HOURS BEFORE TAPERING OFF FROM
NORTH TO SOUTH AROUND MIDNIGHT. MUCH OF THIS SNOW LOOKS TO BE OF THE
BORDERLINE IFR/MVFR VARIETY...WITH ACCUMULATIONS OF AN INCH OR
SLIGHTLY MORE ACROSS SOUTHERN TAF SITES..DTW/YIP/DET...WITH AMOUNTS
LESS FARTHER NORTH. IN-FACT...MBS WILL PROBABLY NOT SEE ANY
MEASURABLE SNOWFALL. DRIER LIGHT NORTHERLY WINDS LATE TONIGHT
LOOK TO CLEAR OUT MUCH OF THE LOW CLOUDS...INTO TOMORROW.
FOR DTW...LIGHT SNOW SHOULD BE ONGOING AT START OF 18Z TAF
PERIOD...CONTINUING THROUGH THIS EVENING...WITH PROLONGED PERIOD OF
2SM SNOW LEADING TO ACCUMULATIONS OF 1 TO 1.5 INCHES BEFORE SNOW
ENDS AROUND OR SHORTLY AFTER MIDNIGHT. WINDS BECOMING A BIT MORE
NORTHERLY OVERNIGHT EXPECTED TO LEAD TO SOME CLEARING...BUT COLD
FLOW OFF LAKE HURON COULD PROLONG CEILINGS A BIT LONGER THAN
FORECASTED.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILING AOB 5000 FEET THROUGH THIS EVENING...MEDIUM
TONIGHT...LOW TOMORROW
* HIGH FOR SNOW AS PRECIPITATION TYPE.
&&
.PREV DISCUSSION...ISSUED 1000 AM EST THU MAR 3 2016
UPDATE...
UPDATE SEND TO GRIDS/TEXT PRODUCTS AS FLURRIES HAVE BEGUN TO FALL
IN ADRIAN WITH 3/2 MILE VSBY JUST UPSTREAM AT HILLSDALE ALREADY.
THE EARLIER TIMING CORRESPONDS WITH A NORTHWARD MOISTURE SURGE
EVIDENT ON WV/RADAR COMPOSITE OVERLAY. 13Z RAP CAPTURES THIS AND
SUGGESTS MID-LEVEL THETA-E ADVECTION IS A BIT MORE ROBUST THAN
PREVIOUSLY THOUGHT. IN ADDITION, THE SHORTWAVE OVER NORTHERN LAKE
MICHIGAN AT 1445Z IS QUITE A BIT STRONGER THAN ADVERTISED IN MODEL
PROGS. THIS FEATURE WILL BE TRANSIENT IN NATURE, EXITING TO THE
EAST BY EARLY AFTERNOON. HOWEVER, IT IS LIKELY PROVIDING A BOOST
TO THE BACKGROUND FORCING FIELD AS WELL AS PROVIDING SOME
ENHANCEMENT TO MOIST ISENTROPIC ASCENT ACROSS LOWER MICHIGAN.
GIVEN THE DRY NATURE OF THE 12Z DTX SOUNDING, ANYTHING THAT SPEEDS
UP THE MOISTENING PROCESS IS A PLUS IN TERMS OF POTENTIAL SNOW
COVERAGE AND ACCUMS. STILL SOME QUESTION AS TO HOW QUICKLY
ACTIVITY WILL SPREAD NORTHEAST, SO TIMING REMAINS ON THE
CONSERVATIVE SIDE FURTHER NORTH FROM 8 MILE. NONETHELESS, THE
AFOREMENTIONED OBSERVATIONS SUPPORT THE 12Z NAM AND ESPECIALLY 13Z
RAP IN A MORE AGGRESSIVE FORECAST FOR THE REMAINDER OF THE DAY.
NOW ADVERTISING ABOUT 3" SOUTH OF I-94 WITH UP TO AN INCH POSSIBLE
AS FAR NORTH AS I-69.
PREV DISCUSSION...ISSUED 349 AM EST THU MAR 3 2016
DISCUSSION...
ACTIVE WEATHER PATTERN WILL CONTINUE RIGHT INTO THE WEEKEND AS
MULTIPLE WAVES TRAVERSE ACROSS THE REGION. UPPER LEVEL TROUGH
CONTINUES TO ALLOW THESE WAVES TO QUICKLY DIVE SOUTH WITH THE FIRST
WAVE CURRENTLY COMING ACROSS THE SOUTHERN PLAINS. THE LOW PRESSURE
SYSTEM IN RESPONSE WILL ALLOW THE NORTHERN EDGE OF THE PRECIP FIELD
TO MOVE OVER SOUTHERN PORTION OF THE CWA AS THE INVERTED TROUGH
SLIDES ACROSS THE AREA. THIS EDGE AT PRESS TIME WAS DROPPING LIGHT
SNOW OVER NORTHERN ILLINOIS/NORTHWEST INDIANA AND WILL SLOWLY EASE
EAST THROUGH THE MORNING HOURS. 00Z MODEL SUITE HAS COME IN WITH A
SLOWER ONSET OF THE SNOW SHOWERS AND A SLIGHT SOUTHERLY SHIFT IN THE
TRACK. THE 00Z SOUNDING FROM DTX ALSO SUPPORTS A LATER ONSET GIVEN
THE AMOUNT OF DRY AIR IN THE COLUMN. PRECIP WILL SLOWLY SATURATE
THROUGH THE MORNING HOURS WITH THE MAJORITY OF THE SNOW SHOWERS
FALLING IN THE AFTERNOON/EARLY EVENING. STILL EXPECTING SNOW
ACCUMULATIONS OF BETWEEN 1-2 INCHES FOR LOCATIONS SOUTH OF DETROIT
WITH 0.5-1 INCH POSSIBLE BETWEEN DETROIT AND FLINT. HIGHEST
SNOWFALL ACCUMULATIONS EXPECTED TO BE FOR LOCATIONS CLOSER TO THE
OHIO BORDER.
A BRIEF BREAK WILL COME ON FRIDAY AS SURFACE HIGH PRESSURE BUILDS IN
BETWEEN THE TWO WAVES. UPPER LEVEL RIDGING BUILDING IN OVERHEAD ON
FRIDAY WILL SLOWLY GIVE WAY AS THE SECOND WAVE MOVES SOUTH FROM THE
NORTHERN PLAINS ON SATURDAY. THIS IS WHERE SOUTHEASTERN MICHIGAN
WILL SEE YET ANOTHER CHANCE FOR PRECIPITATION. ONE CONCERN WITH
THIS SYSTEM IS THE PRECIP TYPE AND HAVE INTRODUCED A RAIN/SNOW MIX
DURING THE AFTERNOON HOURS ON SATURDAY FOR ROUGHLY THE SOUTHERN
THIRD OF THE FORECAST AREA. TEMPS LOOK TO HOVER JUST ABOVE FREEZING
IN THE AFTERNOON AS SOUTHERLY FLOW BRINGS IN THE WARMER TEMPS
ALTHOUGH THIS WILL BE DEPENDENT ON THE TRACK OF THE LOW. WITH THIS
SYSTEM... THE AREA IS LOOKING AT POTENTIAL FOR ANOTHER INCH OR TWO
OF SNOW ONCE IT IS ALL SAID AND DONE. THE SYSTEM WILL QUICKLY EXIT
OFF TO THE SOUTHEAST SATURDAY NIGHT AS HIGH PRESSURE ONCE AGAIN
TAKES OVER FOR THE REMAINDER OF THE WEEKEND.
MORE SUBSTANTIAL CHANGES COME TO THE UPPER LEVELS STARTING NEXT
WEEK. MODEST RIDGING BUILDS IN OVER THE PLAINS AS STRONG HIGH
PRESSURE HOLDS OVER THE SOUTHEAST CONUS. THIS WILL PUT SOUTHEASTERN
MICHIGAN ON THE NORTHERN EDGE OF THE HIGH. WAA ADVECTION WILL
COMMENCE AND BRING ABOVE NORMAL TEMPS BACK TO SOUTHEAST MICHIGAN.
HOWEVER...WHILE TEMPS WILL BE ON THE WARMER SIDE COMPARED TO WHAT
THEY HAVE BEEN...MODELS ARE HINTING AT ANOTHER ACTIVE STRETCH OF
WEATHER AS A BOUNDARY SETS UP RIGHT OVER THE AREA.
MARINE...
A WEAK PRESSURE GRADIENT OVER THE GREAT LAKES REGION WILL ENSURE
LIGHT TO MODERATE WINDS THROUGH THE WEEKEND. SOUTHWEST RETURN FLOW
WILL EVENTUALLY DEVELOP SUNDAY NIGHT AND MONDAY AS LARGE SURFACE
HIGH RETREATS TO THE ATLANTIC SEABOARD.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....SF
UPDATE.......JVC
DISCUSSION...SS
MARINE.......CB
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1000 AM EST THU MAR 3 2016
.UPDATE...
UPDATE SEND TO GRIDS/TEXT PRODUCTS AS FLURRIES HAVE BEGUN TO FALL
IN ADRIAN WITH 3/2 MILE VSBY JUST UPSTREAM AT HILLSDALE ALREADY.
THE EARLIER TIMING CORRESPONDS WITH A NORTHWARD MOISTURE SURGE
EVIDENT ON WV/RADAR COMPOSITE OVERLAY. 13Z RAP CAPTURES THIS AND
SUGGESTS MID-LEVEL THETA-E ADVECTION IS A BIT MORE ROBUST THAN
PREVIOUSLY THOUGHT. IN ADDITION, THE SHORTWAVE OVER NORTHERN LAKE
MICHIGAN AT 1445Z IS QUITE A BIT STRONGER THAN ADVERTISED IN MODEL
PROGS. THIS FEATURE WILL BE TRANSIENT IN NATURE, EXITING TO THE
EAST BY EARLY AFTERNOON. HOWEVER, IT IS LIKELY PROVIDING A BOOST
TO THE BACKGROUND FORCING FIELD AS WELL AS PROVIDING SOME
ENHANCEMENT TO MOIST ISENTROPIC ASCENT ACROSS LOWER MICHIGAN.
GIVEN THE DRY NATURE OF THE 12Z DTX SOUNDING, ANYTHING THAT SPEEDS
UP THE MOISTENING PROCESS IS A PLUS IN TERMS OF POTENTIAL SNOW
COVERAGE AND ACCUMS. STILL SOME QUESTION AS TO HOW QUICKLY
ACTIVITY WILL SPREAD NORTHEAST, SO TIMING REMAINS ON THE
CONSERVATIVE SIDE FURTHER NORTH FROM 8 MILE. NONETHELESS, THE
AFOREMENTIONED OBSERVATIONS SUPPORT THE 12Z NAM AND ESPECIALLY 13Z
RAP IN A MORE AGGRESSIVE FORECAST FOR THE REMAINDER OF THE DAY.
NOW ADVERTISING ABOUT 3" SOUTH OF I-94 WITH UP TO AN INCH POSSIBLE
AS FAR NORTH AS I-69.
&&
.AVIATION...ISSUED 651 AM EST THU MAR 3 2016
RESIDUAL DRY AIR IN THE LOWEST 6000 FT AGL WILL MAKE IT DIFFICULT
FOR PRECIPITATION TO MOVE INTO FAR SOUTHEASTERN MICHIGAN THIS
MORNING. OBSERVATIONAL TRENDS SUPPORT A HIGH AMOUNT OF VIRGA ON
ADJACENT RADARS WHICH MAY MAKE IT DIFFICULT TO PIN DOWN ONSET TIMING
AT THE DETROIT METRO TERMINAL. REALLY LOOKING FOR VFR CONDITIONS IN
BOTH CIGS/VSBYS TO HOLD ON RIGHT INTO THE LATE AFTERNOON HOURS. WARM
ADVECTION WILL THEN INCREASE BY THE EVENING RUSH WHICH WILL SUPPORT
LIGHT ACCUMULATING SNOW AT THE SOUTHERN TERMINALS. WILL CONTINUE TO
BE OPTIMISTIC AND SUPPORT LIGHT SNOW AS FAR NORTH AS FNT...BUT WILL
REMOVE FROM MBS. PEAK OF THE POTENTIAL WILL BE IN THE 21-03Z
TIMEFRAME WHERE HAS MUCH AS AN INCH OF SNOW WILL BE POSSIBLE AT THE
DETROIT TERMINALS.
FOR DTW... VFR CIGS WILL LOWER TO MVFR/IFR DURING THE AFTERNOON
AS SNOW INCREASES COVERAGE AND INTENSITY. ABOUT 1 INCH OF DRY SNOW
ACCUMULATION IS EXPECTED BY LATE THURSDAY EVENING. THERE ARE
INDICATIONS THAT IFR CEILING HEIGHTS WILL AT LEAST APPROACH
SOUTHEASTERN MICHIGAN FROM THE SOUTHWEST ESPECIALLY 23-03Z.
CONFIDENCE IS LOW ATTM.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CIG AOB 5 KFT LATE MORNING THROUGH THURSDAY
EVENING.
* HIGH FOR SNOW AS PRECIPITATION TYPE DURING AFTERNOON AND EVENING.
&&
.PREV DISCUSSION...ISSUED 349 AM EST THU MAR 3 2016
DISCUSSION...
ACTIVE WEATHER PATTERN WILL CONTINUE RIGHT INTO THE WEEKEND AS
MULTIPLE WAVES TRAVERSE ACROSS THE REGION. UPPER LEVEL TROUGH
CONTINUES TO ALLOW THESE WAVES TO QUICKLY DIVE SOUTH WITH THE FIRST
WAVE CURRENTLY COMING ACROSS THE SOUTHERN PLAINS. THE LOW PRESSURE
SYSTEM IN RESPONSE WILL ALLOW THE NORTHERN EDGE OF THE PRECIP FIELD
TO MOVE OVER SOUTHERN PORTION OF THE CWA AS THE INVERTED TROUGH
SLIDES ACROSS THE AREA. THIS EDGE AT PRESS TIME WAS DROPPING LIGHT
SNOW OVER NORTHERN ILLINOIS/NORTHWEST INDIANA AND WILL SLOWLY EASE
EAST THROUGH THE MORNING HOURS. 00Z MODEL SUITE HAS COME IN WITH A
SLOWER ONSET OF THE SNOW SHOWERS AND A SLIGHT SOUTHERLY SHIFT IN THE
TRACK. THE 00Z SOUNDING FROM DTX ALSO SUPPORTS A LATER ONSET GIVEN
THE AMOUNT OF DRY AIR IN THE COLUMN. PRECIP WILL SLOWLY SATURATE
THROUGH THE MORNING HOURS WITH THE MAJORITY OF THE SNOW SHOWERS
FALLING IN THE AFTERNOON/EARLY EVENING. STILL EXPECTING SNOW
ACCUMULATIONS OF BETWEEN 1-2 INCHES FOR LOCATIONS SOUTH OF DETROIT
WITH 0.5-1 INCH POSSIBLE BETWEEN DETROIT AND FLINT. HIGHEST
SNOWFALL ACCUMULATIONS EXPECTED TO BE FOR LOCATIONS CLOSER TO THE
OHIO BORDER.
A BRIEF BREAK WILL COME ON FRIDAY AS SURFACE HIGH PRESSURE BUILDS IN
BETWEEN THE TWO WAVES. UPPER LEVEL RIDGING BUILDING IN OVERHEAD ON
FRIDAY WILL SLOWLY GIVE WAY AS THE SECOND WAVE MOVES SOUTH FROM THE
NORTHERN PLAINS ON SATURDAY. THIS IS WHERE SOUTHEASTERN MICHIGAN
WILL SEE YET ANOTHER CHANCE FOR PRECIPITATION. ONE CONCERN WITH
THIS SYSTEM IS THE PRECIP TYPE AND HAVE INTRODUCED A RAIN/SNOW MIX
DURING THE AFTERNOON HOURS ON SATURDAY FOR ROUGHLY THE SOUTHERN
THIRD OF THE FORECAST AREA. TEMPS LOOK TO HOVER JUST ABOVE FREEZING
IN THE AFTERNOON AS SOUTHERLY FLOW BRINGS IN THE WARMER TEMPS
ALTHOUGH THIS WILL BE DEPENDENT ON THE TRACK OF THE LOW. WITH THIS
SYSTEM... THE AREA IS LOOKING AT POTENTIAL FOR ANOTHER INCH OR TWO
OF SNOW ONCE IT IS ALL SAID AND DONE. THE SYSTEM WILL QUICKLY EXIT
OFF TO THE SOUTHEAST SATURDAY NIGHT AS HIGH PRESSURE ONCE AGAIN
TAKES OVER FOR THE REMAINDER OF THE WEEKEND.
MORE SUBSTANTIAL CHANGES COME TO THE UPPER LEVELS STARTING NEXT
WEEK. MODEST RIDGING BUILDS IN OVER THE PLAINS AS STRONG HIGH
PRESSURE HOLDS OVER THE SOUTHEAST CONUS. THIS WILL PUT SOUTHEASTERN
MICHIGAN ON THE NORTHERN EDGE OF THE HIGH. WAA ADVECTION WILL
COMMENCE AND BRING ABOVE NORMAL TEMPS BACK TO SOUTHEAST MICHIGAN.
HOWEVER...WHILE TEMPS WILL BE ON THE WARMER SIDE COMPARED TO WHAT
THEY HAVE BEEN...MODELS ARE HINTING AT ANOTHER ACTIVE STRETCH OF
WEATHER AS A BOUNDARY SETS UP RIGHT OVER THE AREA.
MARINE...
A WEAK PRESSURE GRADIENT OVER THE GREAT LAKES REGION WILL ENSURE
LIGHT TO MODERATE WINDS THROUGH THE WEEKEND. SOUTHWEST RETURN FLOW
WILL EVENTUALLY DEVELOP SUNDAY NIGHT AND MONDAY AS LARGE SURFACE
HIGH RETREATS TO THE ATLANTIC SEABOARD.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......JVC
AVIATION.....CB
DISCUSSION...SS
MARINE.......CB
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
307 AM EST THU MAR 3 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 412 PM EST WED MAR 2 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL LOW NEAR
JAMES BAY RESULTING IN CONFLUENT NW FLOW THROUGH THE NRN LAKES. AT
THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO TO THE OHIO VALLEY.
HOWEVER LAKE INDUCED TROUGHING HAD DEVELOPED ACROSS PORTIONS OF THE
WRN LAKES. WITH THE LIGHT NRLY FLOW OVER THE REGION...LOW LEVEL CONV
OVER ERN LAKE SUPERIOR ALONG WITH 850 MB TEMPS AROUND -18C SUPPORTED
SCT LES FROM ERN ALGER COUNTY INTO LUCE COUNTY.
TONIGHT...HIGH RES MODELS SUGGEST THAT THE WEAK PRES GRADIENT WILL
FAVOR DEVELOPMENT OF TROUGHING OR EVEN A MESO-LOW OVER ERN LAKE
SUPERIOR. THE LIGHT LES INTO ERN CWA SHOULD CONTINUE INTO THIS
EVENING BEFORE LAND BREEZES AND LAKE INDUCED CIRCULATIONS BECOME
MORE PROMINENT. CONFIDENCE IN WHERE THE LES NEAR THE ERN CWA
SHORELINE WILL DEVELOP IS LOW BUT THE DRY AIRMASS OVER THE REGION
AND INVERSION HEIGHTS REMAINING AOB 5K FT WILL LIMIT THE INTENSITY
WITH ANY ACCUMULATIONS LESS THAN AN INCH. OTHERWISE...PARTLY CLOUDY
SKIES WILL ALLOW ENOUGH RADIATIONAL COOLING FOR TEMPS TO DROP TOWARD
THE LOWER END OF GUIDANCE...ESPECIALLY OVER THE EAST.
THURSDAY...HIGH PRES WILL CONTINUE TO DOMINATE THE REGION WITH DRY
WEATHER AND LIGHT WINDS PREVAILING. ANY LES ON LAKE SUPERIOR SHOULD
REMAIN OFF SHORE. HOWEVER...A LIGHT S TO SE FLOW FROM LAKE MI MAY
BRING SOME SNOW SHOWERS TOWARD THE GARDEN PENINSULA OR SRN
SCHOOLCRAFT COUNTY. AGAIN IN THE WEAK FLOW ENVIRONMENT...CONFIDENCE
IN THE TIMING/LOCATIONS OF ANY LES THAT WILL AFFECT THE CWA IS LOW.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 307 AM EST THU MAR 3 2016
NAM SHOWS THE UPPER AIR PATTERN CONSISTING OF A SHORTWAVE OVER THE
NORTHERN PLAINS 12Z FRI THAT MOVES SOUTHEAST INTO THE UPPER GREAT
LAKES FRI NIGHT AND INTO THE LOWER GREAT LAKES ON SAT. RIDGING THEN
BUILDS INTO THE PLAINS SAT NIGHT. NAM SHOWS DEEPER MOISTURE AND 850-
500 MB Q-VECTOR CONVERGENCE MOVING INTO THE AREA FRI AFTERNOON AND
THE CONVERGENCE MOVES OUT FRI NIGHT. GFS AND ECMWF SHOW ABOUT THE
SAME THING AS WELL. STILL LOOKS LIKE THERE COULD BE A 1-3 INCH
SNOWFALL ACROSS THE CWA FRI AFTERNOON AND FRI NIGHT AND STILL KEPT
IN CHANCE TO LIKELY POPS IN THE CWA WITH THE SNOW MOVING OUT SAT
MORNING. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING
FORECAST.
IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB RIDGE OVER THE PLAINS
12Z SUN THAT MOVES TO THE EAST HALF OF THE U.S. 12Z MON.
MEANWHILE...A BROAD 500 MB TROUGH MOVES INTO THE WESTERN U.S. THE
TROUGH MOVES INTO THE ROCKIES 12Z TUE WITH A SHORTWAVE EJECTING OUT
OF IT INTO THE NORTHERN PLAINS. A BROAD 500 MB TROUGH THEN MOVES
INTO THE SOUTHERN PLAINS 12Z WED. TEMPERATURES WILL REMAIN ABOVE
NORMAL THIS FORECAST PERIOD WITH THE PCPN BEING MOSTLY RAIN AS IT IS
WARM ENOUGH EVEN AT NIGHT FOR IT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1142 PM EST WED MAR 2 2016
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT ALL TAF SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 412 PM EST WED MAR 2 2016WEAK PRESSURE GRADIENT RESULTS
IN WINDS LESS THAN 25 KTS THROUGH SAT. SOUTHWEST WINDS COULD
INCREASE TO 30 KTS ON SUN OVER EASTERN LAKE SUPERIOR AS A DEEP LOW
PRESSURE SYSTEM CROSSING FROM MANITOBA INTO ONTARIO INCREASES
PRESSURE GRADIENT. WINDS ARE EXPECTED TO DROP BLO 25 KTS BY MON AS
GRADIENT WEAKENS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...07
AVIATION...VOSS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1143 PM EST WED MAR 2 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 412 PM EST WED MAR 2 2016
WV IMAGERY AND RAP ANALYSIS INDICATED A MID/UPPER LEVEL LOW NEAR
JAMES BAY RESULTING IN CONFLUENT NW FLOW THROUGH THE NRN LAKES. AT
THE SFC...A RIDGE EXTENDED FROM NRN ONTARIO TO THE OHIO VALLEY.
HOWEVER LAKE INDUCED TROUGHING HAD DEVELOPED ACROSS PORTIONS OF THE
WRN LAKES. WITH THE LIGHT NRLY FLOW OVER THE REGION...LOW LEVEL CONV
OVER ERN LAKE SUPERIOR ALONG WITH 850 MB TEMPS AROUND -18C SUPPORTED
SCT LES FROM ERN ALGER COUNTY INTO LUCE COUNTY.
TONIGHT...HIGH RES MODELS SUGGEST THAT THE WEAK PRES GRADIENT WILL
FAVOR DEVELOPMENT OF TROUGHING OR EVEN A MESO-LOW OVER ERN LAKE
SUPERIOR. THE LIGHT LES INTO ERN CWA SHOULD CONTINUE INTO THIS
EVENING BEFORE LAND BREEZES AND LAKE INDUCED CIRCULATIONS BECOME
MORE PROMINENT. CONFIDENCE IN WHERE THE LES NEAR THE ERN CWA
SHORELINE WILL DEVELOP IS LOW BUT THE DRY AIRMASS OVER THE REGION
AND INVERSION HEIGHTS REMAINING AOB 5K FT WILL LIMIT THE INTENSITY
WITH ANY ACCUMULATIONS LESS THAN AN INCH. OTHERWISE...PARTLY CLOUDY
SKIES WILL ALLOW ENOUGH RADIATIONAL COOLING FOR TEMPS TO DROP TOWARD
THE LOWER END OF GUIDANCE...ESPECIALLY OVER THE EAST.
THURSDAY...HIGH PRES WILL CONTINUE TO DOMINATE THE REGION WITH DRY
WEATHER AND LIGHT WINDS PREVAILING. ANY LES ON LAKE SUPERIOR SHOULD
REMAIN OFF SHORE. HOWEVER...A LIGHT S TO SE FLOW FROM LAKE MI MAY
BRING SOME SNOW SHOWERS TOWARD THE GARDEN PENINSULA OR SRN
SCHOOLCRAFT COUNTY. AGAIN IN THE WEAK FLOW ENVIRONMENT...CONFIDENCE
IN THE TIMING/LOCATIONS OF ANY LES THAT WILL AFFECT THE CWA IS LOW.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 352 PM EST WED MAR 2 2016
BY 00Z FRIDAY...SFC HIGH PRESSURE WILL BE CENTERED ALONG THE
U.S./CANADIAN BORDER BETWEEN THE NEW ENGLAND STATES AND FAR SE
ONTARIO AND S QUEBEC. CLOSER TO HOME...WEAK LOW PRESSURE JUST NW OF
LAKE SUPERIOR WILL SLIDE OVER CENTRAL AND E LAKE SUPERIOR THURSDAY
NIGHT AND BE ACCENTUATED BY AN ELONGATED SHORTWAVE SLIDING IN ON THE
NW FLOW ALOFT. THE SFC LOW WILL BRING THE BEST CHANCE FOR LAKE
EFFECT SNOW SHOWERS TO THE KEWEENAW PENINSULA 09Z-21Z FRIDAY...AS
850MB TEMPS HOVER AROUND -12C.
WAA TAKES HOLD OVER UPPER MI FRIDAY AFTERNOON...AHEAD OF A WARM
FRONT NEARING FROM A SFC LOW ACROSS E ND/W MN. WAA SNOW WILL INVADE
W UPPER MI LATE IN THE DAY AS THE SFC LOW MOVES OVER CENTRAL MN AND
850MB TEMPS RISE TO AROUND -8C. WHILE MOST SOLUTIONS INDICATE THE
SFC LOW SINKING ACROSS CENTRAL WI FRIDAY NIGHT...WITH AN INVERTED
TROUGH MOVING OVER UPPER MI/LAKE SUPERIOR...THERE IS AN OUTLIER
BRINGING THE LOW ACROSS LAKE SUPERIOR. WILL CONTINUE OUR FCST WITH A
CONSENSUS APPROACH...SHIFTING THE LOW ACROSS S WI BY 12Z SATURDAY.
THIS WOULD BRING THE HIGHEST PRECIP TO AREAS ALONG THE WI BORDER
WHERE 850MB TEMPS OF -5 TO -7C. STILL LOOKS LIKE THE PRECIPITATION
SHOULD REMAIN IN THE FORM OF ALL SNOW. QPF TOTALS LOOK TO BE AROUND
0.10 INCHES TO AROUND 0.20 INCHES WITH THE HEAVIEST EXPECTED ALONG
THE WI BORDER WHERE THE BETTER FORCING WILL BE LOCATED. THESE QPF
TOTALS WITH AROUND 13 TO 15 TO SNOW TO LIQUID RATIOS WILL GIVE
SNOWFALL TOTALS AROUND 1 TO 3 INCHES. AGAIN THE HEAVIEST SNOWFALL
TOTALS ARE EXPECTED NEAR THE WI BORDER.
HIGH PRESSURE WILL BUILD IN AT THE SFC SATURDAY AFTERNOON-
EVENING...WITH ONLY A BRIEF TURN OF THE SFC WINDS OUT OF THE NW. BUT
WITH 850MB TEMPS ONLY AROUND -8C OVER THE E HALF...NOT EXPECTING
MUCH MORE THAN CLOUD COVER AND A FEW LIGHT SNOW SHOWERS...THROUGH
EARLY AFTERNOON.
WAA WILL BE MORE IMPRESSIVE SATURDAY NIGHT INTO SUNDAY AS THE SFC
LOW EXITS E AND RIDGING BUILDS IN ALOFT. 850MB TEMPS BY 18Z SUNDAY
WILL INCREASE TO 0 TO 6C /HIGHEST OFF THE GFS AS IT INDICATES 850MB
W-SW FLOW OF 40-55KTS THAT WILL CONTINUE THROUGH 06Z MONDAY/. EXPECT
THE NEXT ROUND OF PRECIP TO START SUNDAY EVENING AS RAIN. THERE ARE
SOME DISCREPANCIES IN THE TIMING OF THE SMALLER SCALE
DISTURBANCES...SO WILL NOT GO TOO HIGH WITH POPS. A REBOUNDING 500MB
RIDGE OVERHEAD SUNDAY NIGHT-MONDAY AND LOW PRESSURE ORGANIZING
ACROSS THE PLAINS STATES WILL ALLOW FOR EVEN INCREASED WAA INTO THE
UPPER GREAT LAKES. BY 12Z TUESDAY 850MB TEMPS WILL LIKELY BE NEAR
8C...ALLOWING SFC TEMPS TO RISE TO NEAR 50F. WITH A STACKED SFC-
500MB LOW ACROSS THE E DAKOTAS AND W MN BY EARLY AFTERNOON...IT
COULD BE AN INTERESTING AFTERNOON ACROSS THE UPPER GREAT LAKES. WILL
WAIT UNTIL FCST SOLUTIONS GET MORE IN LINE BEFORE JUMPING ON ANY
SIGNIFICANT SHOWERS...OR POSSIBLY EVEN A FEW THUNDERSTORMS. AT THIS
POINT THE SFC LOW LOOKS TO EJECT NE...SLIDING JUST NW OF LAKE
SUPERIOR TUESDAY EVENING-EARLY WEDNESDAY MORNING. THE S END OF THE
LOW LOOKS TO INTENSIFY AND MOVE OVER WI/UPPER MI ON WEDNESDAY. THERE
ARE SOME TIMING DIFFERENCES THAT AVERAGE NEARLY 12HRS. COULD BE A
WET AND WARM PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1142 PM EST WED MAR 2 2016
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT ALL TAF SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 412 PM EST WED MAR 2 2016WEAK PRESSURE GRADIENT RESULTS
IN WINDS LESS THAN 25 KTS THROUGH SAT. SOUTHWEST WINDS COULD
INCREASE TO 30 KTS ON SUN OVER EASTERN LAKE SUPERIOR AS A DEEP LOW
PRESSURE SYSTEM CROSSING FROM MANITOBA INTO ONTARIO INCREASES
PRESSURE GRADIENT. WINDS ARE EXPECTED TO DROP BLO 25 KTS BY MON AS
GRADIENT WEAKENS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KEC/KF
AVIATION...VOSS
MARINE...JLB
THROUGH MOST OF THE WEEK. THE PREVIOUS FORECAST DISCUSSION HAD A
GOOD HANDLE ON THE SITUATION AND RELEVANT PORTIONS ARE ATTACHED
BELOW... /DL/
THE WARM AND DRY WEATHER WILL LAST INTO MONDAY BUT RAIN CHANCES LOOK
TO RETURN OVER OUR WESTERN ZONES MONDAY NIGHT. RIDGING ALOFT WILL
STRENGTHEN JUST EAST OF OUR AREA MONDAY IN RESPONSE TO A DEEPENING
UPPER LEVEL LOW OVER THE WESTERN CONUS. THIS RIDGING WILL COMBINE
WITH SURFACE OVER THE SOUTHEAST STATES TO REMAIN DOMINANT OVER OUR
CWA MONDAY INTO MONDAY NIGHT BUT WAA OVER THE SOUTHERN PLAINS AHEAD
OF LARGE CLOSED LOW DROPPING OVER MEXICO WILL RESULT IN CONVECTION
SPREADING INTO OUR CWA FROM THE WEST MONDAY NIGHT.
WAA AHEAD OF THE CLOSED LOW WILL INCREASE OVER OUR CWA TUESDAY. OUR
PWATS WILL INCREASE FROM JUST OVER AN INCH TO NEAR AN INCH AND THREE
QUARTERS BY TUESDAY EVENING GENERALLY WEST OF THE MISSISSIPPI RIVER
WHICH WOULD BE A MAXIMUM FOR THIS TIME OF THE YEAR. WIND FIELDS WILL
INCREASE AND COMBINE WITH INSTABILITY TO RESULT IN SEVERE STORM
POTENTIAL. BIGGEST CHANGE FROM LAST NIGHT`S RUN IS THAT THIS FOCUS
APPEARS TO BE FARTHER WEST TUESDAY AFFECTING MAINLY OUR WESTERN MOST
ZONES. THERE ALSO EXISTS BOTH THE POTENTIAL FOR LOCALLY HEAVY RAIN AS
WELL AS THE TRAINING OF STORMS OVER THE SAME AREA WITH THIS SYSTEM.
MODELS REMAIN IN AGREEMENT THAT THIS LOW WILL BE VERY SLOW TO MOVE
OUT OF THE REGION PERHAPS NOT UNTIL SATURDAY.
AS THE THIS CLOSED LOW SHIFTS EAST TO SOUTHERN TEXAS THURSDAY AND
THEN NORTHEAST TOWARD THE ARKLATEX REGION FRIDAY THE MAIN FEED OF
MOIST GULF AIR AND STORM TRAJECTORIES WILL SET UP ACROSS OUR CWA.
THIS WILL PROLONG THE POTENTIAL FOR HEAVY RAIN AND STRONG TO SEVERE
STORMS ACROSS PORTIONS OF OUR CWA WEDNESDAY INTO FRIDAY. /22/
AVIATION...VFR CONDITIONS ARE PREVAILING THIS AFTERNOON. NORTHERLY
WINDS OF 5-9 KTS THIS AFTERNOON WILL DIMINISH THIS EVENING AND
TONIGHT. LIGHT TO CALM WINDS AND CLEAR SKIES MAY LEAD TO SOME PATCHY
FOG OVERNIGHT/EARLY SATURDAY MORNING THOUGH HIGH CLOUDS MAY HAMPER
THIS. THIS WILL BE MONITORED IN LATER TAF ISSUANCES. PLEASANT WEATHER
WILL CONTINUE THROUGH THE WEEKEND. /28/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 43 72 42 73 / 0 0 0 0
MERIDIAN 39 70 38 71 / 0 0 0 0
VICKSBURG 45 74 43 74 / 0 0 0 0
HATTIESBURG 44 72 43 74 / 0 0 0 0
NATCHEZ 46 73 46 74 / 0 0 0 0
GREENVILLE 42 68 43 69 / 0 0 0 0
GREENWOOD 40 69 40 70 / 0 0 0 0
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
JAN/
AREA FORECAST DISCUSSION...UPDATE
NWS JACKSON MS
1025 AM CST THU MAR 3 2016
.UPDATE... SHOWERS AND EMBEDDED THUNDERSTORMS ARE STREAMING FROM
WEST TO EAST ACROSS CENTRAL AND EAST-CENTRAL MS CURRENTLY...IN
RESPONSE TO AN INCOMING POTENT WEATHER DISTURBANCE ACTIVATING A
BAROCLINIC ZONE RUNNING FROM THE ARKLATEX ESE TOWARD THE CENTRAL
GULF COAST. SURFACE LOW PRESSURE DEEPENING OFF TO OUR WEST SHOULD
MOVE INTO THE HEART OF THE REGION THIS AFTERNOON AND HELP KINK SAID
BAROCLINIC ZONE...BRIEFLY HELPING TO CONGREGATE DEEP LOW LEVEL
INSTABILITY A LITTLE INLAND OF THE GULF COAST. THIS ZONE SHOULD
EXTEND NORTH INTO MY SOUTHEAST ZONE THIS AFTERNOON AND HERE WIND
SHEAR SHOULD BE SUFFICIENT FOR ORGANIZED THUNDERSTORMS ASSOCIATED
WITH A NON-ZERO TORNADO POTENTIAL. LATEST HRRR RUNS BEAR OUT THIS
POTENTIAL WELL...ALTHOUGH IT DOES LOOK LIKE LIKELIHOOD OF SEVERE
ACTIVITY MAY INCREASE AS SURFACE-BASED CONVECTION BEGINS TO
TRANSITION SOUTHEAST OF OUR FORECAST AREA LATE THIS AFTERNOON. ALL
THIS BEING SAID...THE LIMITED RISK OF SEVERE THUNDERSTORMS
PREVIOUSLY POSTED IN THE HWO/GRAPHICS FOR OUR SE ZONES LOOKS
GOOD...ALTHOUGH WE DID UPDATE TIMING TO FOCUS MORE ON THIS AFTERNOON
AND WE ALSO INCLUDED SOME WORDING RELATED TO THE SMALL POSSIBILITY
OF A TORNADO IN THAT NECK-OF-THE-WOODS.
OTHERWISE...EXPECT A CONTINUED SMATTERING OF SHOWERS AND EMBEDDED
THUNDERSTORMS THROUGH THE AFTERNOON (ESPECIALLY OVER MS COUNTIES) AS
IMPRESSIVE LIFT FROM THE INCOMING DISTURBANCE MAKES ITS PRESENCE
FELT. VERY CHILLY TEMPERATURES ALOFT ASSOCIATED WITH THE DISTURBANCE
IS HELPING TO INCREASE 700 TO 500 MB TEMP LAPSE RATES...DELIVERING
ELEVATED INSTABILITY EVEN WHERE THE SURFACE REMAINS COOL. IN MANY
AREAS THIS COMBO OF ELEVATED INSTABILITY AND COLD AIR ALOFT WILL
YIELD SOME SMALL HAIL POTENTIAL AS WE GO THROUGH THE
AFTERNOON...EVEN TO THE NORTH OF OUR LIMITED SVR RISK AREA IN SE MS.
FORTUNATELY...THINKING IS THAT TRULY SEVERE HAIL WITH ANY OF THESE
STORMS OUTSIDE OF THE LIMITED RISK WILL BE HARD TO COME BY...BUT OF
COURSE WE WILL BE MONITORING THE SITUATION CLOSELY.
FINALLY...TEMPS WILL BE TRICKY TODAY WITH A CURRENT LARGE SURFACE
TEMP GRADIENT (WARM TO CHILLY) FROM SW TO NE. EXPECT SURFACE TEMPS
MAY TRY TO RECOVER QUICKLY FROM MID TO LATE AFTERNOON IN AT LEAST
THE SOUTHWEST HALF OF ZONES...ALTHOUGH LOCATIONS IN EAST-CENTRAL MS
AND AROUND THE GOLDEN TRIANGLE MAY SEE THE SUN SET TOO SOON TO
BENEFIT. THIS UPDATE REFLECTS THIS THINKING. /BB/
&&
.AVIATION...MVFR CIGS PREVAIL ACROSS THE REGION THIS MORNING DUE TO
LOW STRATUS. SCT SHRA WITH SOME EMBEDDED TS ENCOMPASSED MUCH OF
CENTRAL MS. THIS ACTIVITY WILL CONTINUE THROUGH THE DAYTIME HOURS AS
A COLD FRONT MOVES ACROSS THE REGION. A FEW SEVERE STORMS ARE
POSSIBLE. CIGS ARE EXPECTED TO REMAIN IN THE MVFR (OCCASIONALLY IFR)
RANGE OVER MOST OF THE AREA THROUGH TONIGHT, IMPROVING TO VFR BY
EARLY FRIDAY. AS THE FRONT MOVES THROUGH, WINDS WILL SHIFT FROM S/SE
THIS MORNING TO W/NW THIS AFTERNOON INTO TONIGHT AS THE FRONT MOVES
SOUTHEASTWARD ACROSS THE AREA. A FEW GUSTS TO AROUND 20 KT ARE
POSSIBLE THIS AFTERNOON. /DL/
&&
.PREV DISCUSSION... /ISSUED 447 AM CST THU MAR 3 2016/
SHORT TERM...TODAY THROUGH SATURDAY MORNING...OVERALL MAIN STORY
FOR THE SHORT TERM PERIOD ARE THE RAIN AND STORM CHANCES MOVING IN
THIS MORNING TO AFTERNOON BEFORE A QUIETER AND DRIER PERIOD IN STORE
GOING INTO THE WEEKEND.
FAST MOVING S/WV MOVING INTO SRN AR IS BRINGING A MCS INTO THE NW
DELTA EARLY THIS MORNING. DUE TO VERY LOW DEWPOINTS IN THE UPPER 30S
ACROSS MOST OF THE REGION...THIS WILL LIKELY REMAIN ELEVATED BUT
SOME OCCASIONAL PRECIP LOADING COULD BRING DOWN SOME QUICK GUSTY
WINDS. THIS IS IN RESPONSE TO A QUICK MOVING UPPER JET/SFC LOW
MOVING INTO NRN TX/SRN OK. EXPECT THIS TO RAPIDLY MOVE TO THE E
TODAY AND CONTINUE TO HELP INCREASE LOW LEVEL FLOW AND MOISTURE
RETURN WITH DEWPOINTS GETTING INTO THE UPPER 50S/LOWER 60S IN THE S.
OVERALL MOST OF THE ACTIVITY TODAY WILL REMAIN TAME DUE TO STRONG
LOW LEVEL INVERSION BUT AFTER THE 21Z TIMEFRAME OR SO...THAT
INVERSION SHOULD BE MOSTLY MIXED OUT AND SOME LOW LEVEL
INSTABILITY...DUE TO STEEP MID-LEVEL LAPSE RATES...WILL BE ABLE TO
BE REALIZED. BASED ON HI-RES ARW AND GOOD LOW LEVEL SHEAR...WENT
AHEAD AND INTRODUCED A LIMITED IN THE HWO FOR SEVERE IN THE HWY 84
CORRIDOR. ALSO THE HIGHS TODAY WENT A LITTLE ON THE COOLER SIDE DUE
TO THE INVERSION STICKING AROUND AWHILE AND OP GFS/EURO BEING MUCH
COOLER...WENT A FEW DEGREES COOLER.
EXPECT THE ~1010MB SFC LOW AND ASSOCIATED LIFT/RAIN TO MOVE THROUGH
AFTER 00Z TONIGHT AND RAIN TO TAPER OFF BETWEEN 03-06Z FRIDAY. AFTER
THE SFC LOW MOVES THROUGH...EXPECT NW FLOW AND SFC RIDGING TO BUILD
IN AND HELP TO DRY OUT THE AREA AS PW`S FALL TO LESS THAN HALF AN
INCH. THIS WILL LEAD TO A MUCH DRIER PATTERN AND CLOUDS WILL CLEAR
OUT OF THE AREA FRIDAY AFTERNOON. A NICE AFTERNOON IS IN STORE ON
FRIDAY BUT SOME NE SFC WINDS WILL KEEP THE AREA FROM WARMING AS MUCH
WITH HIGHS IN THE UPPER 50S IN THE N TO MID/UPPER 60S IN THE S.
EXPECT ANOTHER COLD NIGHT IN STORE IN THE MID 30S IN THE E TO LOW
40S IN THE WEST. /DC/
LONG TERM...SATURDAY THROUGH THURSDAY...WARMING TREND BEGINS
SATURDAY AND WILL CONTINUE...ALONG WITH DRY WEATHER...THROUGH
TUESDAY. A SURFACE RIDGE WILL BE OVER THE SOUTHEAST STATES SATURDAY
MORNING RESULTING IN RETURN FLOW OVER OUR CWA BUT THIS WILL BE SHORT
LIVED. A NORTHERN STREAM SHORTWAVE TROUGH AND WEAK SURFACE LOW WILL
MOVE SOUTHEAST ACROSS THE OHIO VALLEY SATURDAY AND TO THE MID
ATLANTIC SEABOARD BY SUNDAY MORNING. THE WEAK DRY TRAILING COLD
FRONT WILL DROP SOUTH INTO OUR NORTHEAST ZONES EARLY SUNDAY MORNING
BEFORE DISSIPATING. IN ITS WAKE A 1028MB HIGH WILL BECOME CENTERED
OVER THE MID MISSISSIPPI RIVER VALLEY PROVIDING A LIGHT DRY
NORTHEAST TO EAST FLOW BACK ACROSS OUR CWA SUNDAY. RIDGING ALOFT
WILL STRENGTHEN JUST EAST OF OUR AREA IN RESPONSE TO A DEEPENING
UPPER LEVEL TROUGH OVER THE WESTERN CONUS SUNDAY INTO MONDAY.
RIDGING SURFACE AND ALOFT CENTERED OVER THE EASTERN CONUS WILL
REMAIN DOMINANT OVER OUR CWA INTO MONDAY MAINTAINING DRY WEATHER
OVER OUR CWA. THIS WILL ALLOW TEMPERATURES TO WARM BACK ABOVE NORMAL
BY SUNDAY AND CONTINUE ABOVE NORMAL THROUGH THURSDAY. THE DRY
WEATHER WILL NOT LAST THOUGH. MODELS ARE IN DECENT AGREEMENT WITH
THE DEVELOPMENT OF A CLOSED LOW OVER MEXICO BY TUESDAY MORNING. WAA
AHEAD OF THIS LOW WILL INCREASE OVER OUR CWA TUESDAY. OUR PWATS WILL
INCREASE FROM JUST OVER AN INCH TO NEAR AN INCH AND THREE QUARTERS
BY TUESDAY EVENING OVER THE WESTERN HALF OF OUR CWA. THIS ANOMALOUS
PWAT IS WOULD BE A MAXIMUM FOR THIS TIME OF THE YEAR. WIND FIELDS
WILL INCREASE AND COMBINE WITH INSTABILITY TO RESULT IN SEVERE STORM
POTENTIAL. THIS EXISTS BOTH THE POTENTIAL FOR HEAVY RAIN AS WELL AS
THE TRAINING OF STORMS OVER THE SAME AREA. THE MAIN AREA FOR SEVERE
WEATHER TUESDAY AND TUESDAY NIGHT WILL BE WEST OF INTERSTATE 55
AND WL INCLUDE THIS POTENTIAL IN THE HWO. MODELS ARE SLOW TO MOVE
THIS CLOSED LOW OUT AND BOTH THE GFS AND THE ECMWF HAVE THE LOW
STILL OVER MEXICO THURSDAY EVENING. AS THE LOW SHIFTS EAST TOWARD
TEXAS TUESDAY THROUGH THURSDAY THE AXIS OF HEAVIEST RAIN AND SEVERE
STORM POTENTIAL WILL SHIFT FARTHER EAST OVER OUR CWA. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 66 44 64 40 / 65 16 1 1
MERIDIAN 61 41 64 37 / 82 24 1 1
VICKSBURG 71 45 65 44 / 51 10 0 1
HATTIESBURG 69 47 68 40 / 66 26 1 1
NATCHEZ 73 47 66 45 / 36 10 1 1
GREENVILLE 65 43 59 42 / 53 10 1 1
GREENWOOD 62 41 60 40 / 68 13 1 1
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
BB/DL/DC/22
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1201 PM CST THU MAR 3 2016
.SHORT TERM: (Through Late This Afternoon)
Issued at 316 AM CST Thu Mar 3 2016
Main concern will be timing of precipiation today.
Regional radar and water vapor is showing a vort max circulation
currently just northwest of Columbia that will continue to move
east early this morning. Light rain over central and northeast
Missouri as well as west central Illinois is being generated by
low level moisture convergence as well as ascent caused by the
vort max. Expect that light rain will continue to spread across
the area this morning and then end from west to east this
afternoon as shortwave trough now back over the Central Plains
sweeps across the area. Forecast soundings and surface
temperatures from the RAP and other models continue to show that
this will be an all rain system. Temperatures will be held in
check by the rain and clouds.
.LONG TERM: (Tonight through Wednesday)
Issued at 310 AM CST Thu Mar 3 2016
Have a dry forecast now through late Sunday as the GFS/ECMWF/NAM are
all tracking the system that moves across the Upper Midwest and
Great Lakes on Friday night and Saturday will keep precipitation
northeast of the CWA. It still appears that we will be going from
below normal temperatures on Friday to above normal temperatures
on Saturday and Sunday as the upper pattern switches from
northwesterly to southwesterly.
Both the ECWMF and the GFS are showing persisent southwesterly flow
setting up early-mid next week which will allow for plenty of moisture
to move northward from the Gulf of Mexico. Will continue the high
chance of showers and thunderstorms going beginning Sunday night
through Wednesday. Will need to watch the potential for locally
heavy rainfall with this system if the front stalls over CWA.
Britt
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1151 AM CST Thu Mar 3 2016
A surface low pressure system was located in SW MO at midday with
an area of light rain centered from St. Louis into SE MO. The low
will move southeastward through the remainder of the afternoon and
evening with the rain persisting into early-mid afternoon for the
St. Louis area terminals. In the wake of the low pressure system,
surface winds will shift to the north-northwest and this will
bring an extensive area of stratus out of IA into the area, and
will also keep the stratus currently across eastern MO locked in.
MVFR flight conditions will be most predominate with KUIN
continuing to experiencing IFR through the afternoon. There may be
another period again of IFR towards daybreak on Friday morning.
Flight conditions should improve to VFR late morning-midday on
Friday.
Specifics for KSTL:
Light rain will persist into early-mid afternoon as a low pressure
system tracks to the southeast of the area. In the wake of the
low pressure system, surface winds will shift to the north-
northwest and this keep the stratus currently across eastern MO
locked in. MVFR flight conditions will be most predominate. Flight
conditions should improve to VFR late morning-midday on Friday.
Glass
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
454 AM CST THU MAR 3 2016
.SHORT TERM: (Through Late This Afternoon)
Issued at 316 AM CST Thu Mar 3 2016
Main concern will be timing of precipiation today.
Regional radar and water vapor is showing a vort max circulation
currently just northwest of Columbia that will continue to move
east early this morning. Light rain over central and northeast
Missouri as well as west central Illinois is being generated by
low level moisture convergence as well as ascent caused by the
vort max. Expect that light rain will continue to spread across
the area this morning and then end from west to east this
afternoon as shortwave trough now back over the Central Plains
sweeps across the area. Forecast soundings and surface
temperatures from the RAP and other models continue to show that
this will be an all rain system. Temperatures will be held in
check by the rain and clouds.
.LONG TERM: (Tonight through Wednesday)
Issued at 310 AM CST Thu Mar 3 2016
Have a dry forecast now through late Sunday as the GFS/ECMWF/NAM are
all tracking the system that moves across the Upper Midwest and
Great Lakes on Friday night and Saturday will keep precipitation
northeast of the CWA. It still appears that we will be going from
below normal temperatures on Friday to above normal temperatures
on Saturday and Sunday as the upper pattern switches from
northwesterly to southwesterly.
Both the ECWMF and the GFS are showing persisent southwesterly flow
setting up early-mid next week which will allow for plenty of moisture
to move northward from the Gulf of Mexico. Will continue the high
chance of showers and thunderstorms going beginning Sunday night
through Wednesday. Will need to watch the potential for locally
heavy rainfall with this system if the front stalls over CWA.
Britt
&&
.AVIATION: (For the 12z TAFs through 12z Friday Morning)
Issued at 419 AM CST Thu Mar 3 2016
Light rain will move eastward through our area this morning ahead
of an upper level disturbance and an inverted surface trough. The
light rain should shift east of COU by about 14Z, east of UIN by
17Z, and east of the St Louis metro area by 20Z. The cloud ceiling
will drop into the MVFR catagory by late morning. The e-sely
surface wind will back around to a nly direction by late morning
in UIN and COU and during the afternoon in the St Louis metro area
after the passage of the inverted surface trough. MVFR cigs should
rise into the VFR catagory by late tonight.
Specifics for KSTL: Light rain will move eastward into STL early
this morning, then shift east of STL during the early afternoon.
The cloud ceiling will lower in the MVFR catagory by late morning.
The ely surface wind will become sely later this morning, then
back around to a n-nwly direction by late afternoon. The MVFR cigs
should rise into the VFR catagory late tonight. The surface wind
will become light Friday morning as a surface ridge axis moves
over STL.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1131 PM CST WED MAR 2 2016
.UPDATE:
Issued at 920 PM CST Wed Mar 2 2016
Currently, the main upper level energy associated with the system
for later tonight and Thursday is over the northern High Plains,
near the interface between Wyoming and western South Dakota. There
is persistent WAA over our region now in advance of the system,
most focused in an axis from central IA to northwest MO, but it
is still taking some time to saturate the lower layers before pcpn
can initiate. A few stray sprinkles are not out of the question
for the remainder of this evening.
The main energy is expected to dig into western AR Thursday
morning, while driving a lead disturbance thru northern AR into
TN. These two main drivers now appear to take much of the best
WAA and broadscale lift south with them. While this does work
over our region, it will only do so briefly and then collapses to
the south. This has been picked up by the HRRR and RAP, which
significantly reduce the QPF over our region to near zero in many
areas. But one thing the HRRR and RAP are missing out on is that
there is currently strong WAA over the interface of NE/KS/MO and
this is producing rain, although the coverage on radar is worse
than what is actually hitting the ground. What all of this
appears to be saying is that the energy needed to saturate the
column sufficiently to achieve rain is going to be close to what
will actually happen and we are being given large divergences on
forecast rainfall amounts, depending on whether that threshold is
met or not. It all seemed much more achievable a model run ago. As
it stands now, the best chances for rainfall look to be northeast
MO, as the pcpn enters from the west with weakening lift, and
southeast MO which will gain benefit of the more southerly digging
main system.
Will only make minor changes to the forecast at this stage,
trimming slightly but maintaining the high PoPs in spots (only
0.01" needed), but backing off on QPF amounts.
Lots of low clouds still expected Thursday, and cool temps seem to
be the way to go with this setup and winds turning from east to
north.
TES
&&
.SHORT TERM: (Through Thursday)
Issued at 243 PM CST Wed Mar 2 2016
Hybrid clipper will begin to impact the CWA overnight tonight and
continue into the day on Thursday. System has pushed slightly to
the southwest compared to 24 hours ago. Main impacts for this
southwestward adjustment include increasing PoPs into the
categorical category as well as cooling high temperatures on
Thursday.
Expect strong warm/moist advection in conjunction with increasing
upper-level forcing for ascent to develop widespread light rain late
this evening near the MO/IA border. This are of rain should expand
southward due to a strengthening nocturnal LLJ but also advect to
the south and east as well. Precipitation for our CWA...even with a
slight adjustment of the system track to the south and west...still
appears to be all liquid rain due to temperatures above freezing at
lower levels.
As alluded to above...had to cool high temperatures for a majority
of the CWA on Thursday several degrees. Surface low on Thursday now
looks to track southwest of a KIRK>>KSTL>>KSLO line which will put
at least the northeastern 1/2 of the CWA in the cold sector of the
cyclone. A chilly...raw early March day looks on tap for most with
light rain...low clouds...and highs in the 40s. By afternoon...rain
should push off to the south and east of the CWA.
Gosselin
.LONG TERM: (Thursday through Next Wednesday)
Issued at 243 PM CST Wed Mar 2 2016
Mostly quiet weather with moderating temperatures back above normal
by this upcoming weekend still looks in store.
Very unsettled weather should take hold early next week with
potentially multiple rounds of showers and thunderstorms. Best bet
of this activity for now appears to be in the Tuesday/Tuesday night
timeframe.
Though still many days away...the pattern next week looks quite
ominous with meridional flow throughout the troposphere. This
would in turn supply much of the lower and mid-Mississippi Valley
with tons of Gulf moisture. If the baroclinic zone does not
progress much southeastward through the week...there will be more
than enough rain to cause problems across the region as round
after round of showers w/ possible embedded convection could
affect many of the same areas.
Gosselin
&&
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1131 PM CST Wed Mar 2 2016
Flight category conditions are expected to transition from VFR at
all sites currently to at least MVFR by late tonight into early
Thursday morning with some IFR possible. As it stands now, the
best chances for IFR remain in UIN and have kept the mention in
the 06z TAF. Elsewhere, it looks like the trend to delay the rain
a bit and have it struggle advecting eastward into the STL metro
area will probably also cause a delay with the MVFR CIGs moving
in, and as a result, have delayed in STL metro until mid to late
morning. But once these CIGs move in, they should stay for much,
if not all, the remainder of the valid TAF period. Some clearing
expected late Thursday night, but beyond the valid period for most
TAFs. Otherwise, look for easterly winds to shift northerly
during the day on Thursday, either late morning or early afternoon
at the TAF sites as an inverted TROF works thru.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
924 AM MST THU MAR 3 2016
.UPDATE...
THE FOG IS DISSIPATING AROUND BAKER...BUT VISIBILITY IS STILL
AROUND 2 MILES...SO EXTENDED THE MENTION OF FOG FOR ANOTHER HOUR.
OTHERWISE TWEAKED TEMPS AND HUMIDITY BASED ON CURRENT TRENDS.
REST OF THE FORECAST LOOK GOOD. REIMER
&&
.SHORT TERM...VALID FOR TDY AND FRI...
THE MAIN THEME FOR THE NEXT COUPLE OF DAYS IS FOR MILD WEATHER TO
TAKE HOLD THROUGH THE END OF THE WEEK. HIGH TEMPERATURES WILL
REACH IN THE 60S TO END THE WEEK...AND AS YOU WILL SEE IN THE
EXTENDED FORECAST...EVEN A 70 DEGREE HIGH IS POSSIBLE SATURDAY.
THE BEST CHANCE OF PRECIPITATION WILL COME TONIGHT WITH THE
PASSAGE OF A WEAK SHORTWAVE.
A QUIETER DAY IS IN STORE TODAY AS FLAT RIDGING TAKES OVER. MID
LEVEL FLOW BACKS AND DOWNSLOPE WARMING IN RESPONSE HAS 850MB
TEMPERATURES RISING TO AROUND 12C. THIS WOULD TRANSLATE TO HIGH
TEMPERATURES IN THE UPPER 50S TO LOWER 60S. A LEE SURFACE TROUGH
WAS FORMING THIS MORNING AND THIS HAS CAUSED WINDS TO GUST TO
AROUND 45 MPH AT LIVINGSTON. GRADIENT WILL CONTINUE THIS MORNING
THEN TURN MORE WESTERLY THIS AFTERNOON. BUMPED WINDS UP FOR
LIVINGSTON BUT KEPT THEM BELOW ADVISORY CRITERIA. THE REST OF THE
AREA WILL BE A LITTLE BREEZY BUT WINDS WILL BE MUCH LIGHTER
COMPARED TO YESTERDAY. FOG HAS FORMED IN BAKER THIS MORNING WITH
VISIBILITY DROPPING BELOW A MILE. EVENING CREW ADDED FOR THIS
MORNING AND WILL LEAVE IN. HRRR LIFTS FOG OUT BY LATE MORNING SO
DID MAKE THAT ADJUSTMENT.
SHORTWAVE ENERGY WILL CRASH THE RIDGE TONIGHT AND THIS WILL
SPREAD MID LEVEL MOISTURE AND ASCENT IN THIS EVENING. AS THE WAVE
DROPS SOUTHEAST TOWARD THE CENTRAL PLAINS...ASCENT WILL BE DRIVEN
INTO THE SOUTHERN SECTIONS OVERNIGHT. RAISED POPS TO SCATTERED AS
A DECENT SLUG OF MOISTURE AND SOME INSTABILITY WERE AVAILABLE. THE
SHORTWAVE WAS WEAKER THAN THE LAST FEW THAT HAVE COME THROUGH AND
WILL BE WORKING AGAINST DOWNSLOPE FLOW...SO WILL KEEP THE HIGHER
POPS IN THE MOUNTAINS.
THE SHORTWAVE EXISTS INTO THE PLAINS FRIDAY NIGHT AND IS REPLACED
BY A RIDGE. FRIDAY SHOULD BE MILD AGAIN DESPITE LINGERING CLOUDS
EARLY IN THE DAY. CLOUDS WILL CLEAR OUT BY AFTERNOON AND THIS WILL
ALLOW THE RIDGE AXIS TO PRODUCE LOWER 60S MOST LOCATIONS. TWH
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MADE A FEW CHANGES TO THE EXTENDED FORECAST PERIOD THIS
MORNING...CONCENTRATED ON RAISING WEEKEND TEMPS AND TWEAKING OF
POPS ASSOCIATED WITH WAVES CROSSING THE REGION THROUGH THE PERIOD.
OVERALL...THE STORY FOR THE EXTENDED PERIOD REMAINS THE SAME
HOWEVER...WITH AN UPPER LEVEL RIDGE DOMINATING THE PATTERN.
TEMPERATURES SHOULD BE WELL ABOVE NORMAL THROUGH THE WEEKEND...AND
RAISED HIGHS FOR SATURDAY AND SUNDAY...EVEN THOUGH THE APPEARS TO
FLATTEN...GIVING WAY TO A LONG WAVE PACIFIC TROUGH MOVING IN FROM
THE PACIFIC COAST. THIS CHANGE MARKS THE BEGINNING OF A STRETCH OF
POTENTIALLY UNSETTLED WEATHER WITH SEVERAL SHORTWAVES
TRANSITIONING THROUGH THE FLOW. IT WILL ALSO MARK THE START OF
STRETCH OF COOLER TEMPERATURES...WITH MID 50S MOST OF NEXT WEEK.
THE BEST CHANCE FOR ANY WIDESPREAD PRECIPITATION WILL COME SUNDAY
EVENING INTO MONDAY AS A DISTURBANCE CROSSES THER REGION. WEAKER
SHORTWAVES WILL SLIDE THROUGH THE REGION THROUGH THE REMAINDER OF
THE THE WORK WEEK...WITH MAINLY MOUNTAIN POPS...BUT SLIGHTS
CHANCES INTO THE PLAINS AS WELL. GILSTAD
&&
.AVIATION...
MAINLY VFR CONDITIONS TODAY. A DISTURBANCE CROSSING THE REGION
WILL BRING ISOLATED TO SCATTERED SHOWERS ACROSS THE REGION THIS
EVENING...WITH LOCALIZED MVFR CONDITIONS POSSIBLE IN SHOWERS. BEST
POTENTIAL FOR PRECIP WILL BE IN BEARTOOTH/ABSAROKAS
MOUNTAINS...WITH INCREASING OBSCURATIONS THROUGH THE DAY...THEN
PERSISTENT OBSCURATIONS THROUGH THE NIGHT...IN SNOW.
GILSTAD/CHAMBERS
&&
.PRELIMINARY POINT TEMP/POPS...
TDY FRI SAT SUN MON TUE WED
-------------------------------------------------------
BIL 060 036/062 038/070 039/067 038/056 032/052 031/056
0/B 30/U 00/U 01/U 42/W 11/B 22/W
LVM 059 034/057 036/066 040/061 033/051 029/050 031/052
2/W 41/U 01/N 12/W 42/W 12/W 22/W
HDN 061 032/062 031/071 034/069 035/059 028/054 028/058
0/B 30/U 00/U 01/U 42/W 11/B 22/W
MLS 059 034/060 031/070 034/069 036/057 029/053 028/055
0/B 30/U 00/U 00/U 33/W 21/B 21/B
4BQ 059 033/059 031/070 034/070 035/056 027/052 028/057
0/B 30/U 00/U 00/U 33/W 21/B 21/B
BHK 053 031/054 028/068 032/069 034/054 027/048 026/052
0/B 30/U 00/U 00/U 23/W 21/B 21/B
SHR 059 030/057 028/068 033/066 034/053 026/051 025/056
0/B 31/B 00/U 00/U 43/W 22/W 21/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
340 AM MST THU MAR 3 2016
.SHORT TERM...VALID FOR TDY AND FRI...
THE MAIN THEME FOR THE NEXT COUPLE OF DAYS IS FOR MILD WEATHER TO
TAKE HOLD THROUGH THE END OF THE WEEK. HIGH TEMPERATURES WILL
REACH IN THE 60S TO END THE WEEK...AND AS YOU WILL SEE IN THE
EXTENDED FORECAST...EVEN A 70 DEGREE HIGH IS POSSIBLE SATURDAY.
THE BEST CHANCE OF PRECIPITATION WILL COME TONIGHT WITH THE
PASSAGE OF A WEAK SHORTWAVE.
A QUIETER DAY IS IN STORE TODAY AS FLAT RIDGING TAKES OVER. MID
LEVEL FLOW BACKS AND DOWNSLOPE WARMING IN RESPONSE HAS 850MB
TEMPERATURES RISING TO AROUND 12C. THIS WOULD TRANSLATE TO HIGH
TEMPERATURES IN THE UPPER 50S TO LOWER 60S. A LEE SURFACE TROUGH
WAS FORMING THIS MORNING AND THIS HAS CAUSED WINDS TO GUST TO
AROUND 45 MPH AT LIVINGSTON. GRADIENT WILL CONTINUE THIS MORNING
THEN TURN MORE WESTERLY THIS AFTERNOON. BUMPED WINDS UP FOR
LIVINGSTON BUT KEPT THEM BELOW ADVISORY CRITERIA. THE REST OF THE
AREA WILL BE A LITTLE BREEZY BUT WINDS WILL BE MUCH LIGHTER
COMPARED TO YESTERDAY. FOG HAS FORMED IN BAKER THIS MORNING WITH
VISIBILITY DROPPING BELOW A MILE. EVENING CREW ADDED FOR THIS
MORNING AND WILL LEAVE IN. HRRR LIFTS FOG OUT BY LATE MORNING SO
DID MAKE THAT ADJUSTMENT.
SHORTWAVE ENERGY WILL CRASH THE RIDGE TONIGHT AND THIS WILL
SPREAD MID LEVEL MOISTURE AND ASCENT IN THIS EVENING. AS THE WAVE
DROPS SOUTHEAST TOWARD THE CENTRAL PLAINS...ASCENT WILL BE DRIVEN
INTO THE SOUTHERN SECTIONS OVERNIGHT. RAISED POPS TO SCATTERED AS
A DECENT SLUG OF MOISTURE AND SOME INSTABILITY WERE AVAILABLE. THE
SHORTWAVE WAS WEAKER THAN THE LAST FEW THAT HAVE COME THROUGH AND
WILL BE WORKING AGAINST DOWNSLOPE FLOW...SO WILL KEEP THE HIGHER
POPS IN THE MOUNTAINS.
THE SHORTWAVE EXISTS INTO THE PLAINS FRIDAY NIGHT AND IS REPLACED
BY A RIDGE. FRIDAY SHOULD BE MILD AGAIN DESPITE LINGERING CLOUDS
EARLY IN THE DAY. CLOUDS WILL CLEAR OUT BY AFTERNOON AND THIS WILL
ALLOW THE RIDGE AXIS TO PRODUCE LOWER 60S MOST LOCATIONS. TWH
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MADE A FEW CHANGES TO THE EXTENDED FORECAST PERIOD THIS
MORNING...CONCENTRATED ON RAISING WEEKEND TEMPS AND TWEAKING OF
POPS ASSOCIATED WITH WAVES CROSSING THE REGION THROUGH THE PERIOD.
OVERALL...THE STORY FOR THE EXTENDED PERIOD REMAINS THE SAME
HOWEVER...WITH AN UPPER LEVEL RIDGE DOMINATING THE PATTERN.
TEMPERATURES SHOULD BE WELL ABOVE NORMAL THROUGH THE WEEKEND...AND
RAISED HIGHS FOR SATURDAY AND SUNDAY...EVEN THOUGH THE APPEARS TO
FLATTEN...GIVING WAY TO A LONG WAVE PACIFIC TROUGH MOVING IN FROM
THE PACIFIC COAST. THIS CHANGE MARKS THE BEGINNING OF A STRETCH OF
POTENTIALLY UNSETTLED WEATHER WITH SEVERAL SHORTWAVES
TRANSITIONING THROUGH THE FLOW. IT WILL ALSO MARK THE START OF
STRETCH OF COOLER TEMPERATURES...WITH MID 50S MOST OF NEXT WEEK.
THE BEST CHANCE FOR ANY WIDESPREAD PRECIPITATION WILL COME SUNDAY
EVENING INTO MONDAY AS A DISTURBANCE CROSSES THER REGION. WEAKER
SHORTWAVES WILL SLIDE THROUGH THE REGION THROUGH THE REMAINDER OF
THE THE WORK WEEK...WITH MAINLY MOUNTAIN POPS...BUT SLIGHTS
CHANCES INTO THE PLAINS AS WELL. GILSTAD
&&
.AVIATION...
MAINLY VFR CONDITIONS TODAY...WITH SOME PATCHY FOG POSSIBLE
AROUND KMLS AND KBHK THROUGH MID MORNING. A DISTURBANCE CROSSING
THE REGION WILL BRING ISOLATED TO SCATTERED SHOWERS ACROSS THE
REGION THIS EVENING...WITH LOCALIZED MVFR CONDITIONS POSSIBLE IN
SHOWERS. BEST POTENTIAL FOR PRECIP WILL BE IN BEARTOOTH/ABSAROKAS
MOUNTAINS...WITH INCREASING OBSCURATIONS THROUGH THE DAY...THEN
PERSISTENT OBSCURATIONS THROUGH THE NIGHT...IN SNOW. GILSTAD
&&
.PRELIMINARY POINT TEMP/POPS...
TDY FRI SAT SUN MON TUE WED
-------------------------------------------------------
BIL 060 036/062 038/070 039/067 038/056 032/052 031/056
0/B 30/U 00/U 01/U 42/W 11/B 22/W
LVM 060 034/057 036/066 040/061 033/051 029/050 031/052
2/W 41/U 01/N 12/W 42/W 12/W 22/W
HDN 061 032/062 031/071 034/069 035/059 028/054 028/058
0/B 30/U 00/U 01/U 42/W 11/B 22/W
MLS 059 034/060 031/070 034/069 036/057 029/053 028/055
0/B 30/U 00/U 00/U 33/W 21/B 21/B
4BQ 060 033/059 031/070 034/070 035/056 027/052 028/057
0/B 30/U 00/U 00/U 33/W 21/B 21/B
BHK 053 031/054 028/068 032/069 034/054 027/048 026/052
0/B 30/U 00/U 00/U 23/W 21/B 21/B
SHR 059 030/057 028/068 033/066 034/053 026/051 025/056
0/B 31/B 00/U 00/U 43/W 22/W 21/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
526 AM CST THU MAR 3 2016
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 315 AM CST THU MAR 3 2016
FORECAST CONCERNS THROUGH THE SHORT TERM WILL MAINLY BE
TEMPERATURES AND CLOUDS.
THE OAX 00Z SOUNDING WAS MOIST ABOVE H6 WITH A PWAT OF 0.49 INCHES.
THE H3 130 JET STRETCHED FROM MONTANA TO WYOMING AND COLORADO.
THERE WERE 60-80M HEIGHT FALLS OVER COLORADO AND WESTERN KANSAS
WITH EMBEDDED SHORTWAVES IN THE NORTHWEST FLOW ALOFT. CLUSTERS OF
STORMS WERE BETTER ORGANIZED OVER WESTERN NEBRASKA...NORTHERN
KANSAS AND SOUTH INTO OKLAHOMA WITH RAIN AND SPOTTY SHOWERS FOR
THE LOCAL AREA. AT 09Z...THE LATEST SURFACE ANALYSIS HAD AN
ELONGATED AREA OF SURFACE LOW PRESSURE FROM NORTHERN TEXAS INTO
EASTERN KANSAS...WITH AND INVERTED TROF FEATURE BACK TOWARD
ONEILL AND INTO SOUTH DAKOTA. TEMPERATURES WERE IN THE 20S AND
30S WITH NORTH WINDS MAINLY 5 TO 10 MPH. AT 0930Z...A BAND
RAIN/FREEZING RAIN/RAIN SNOW MIX EXTENDED FROM PRAGUE TO SEWARD TO
FRIEND. SEWARD COUNTY SAID IT WAS ALL RAIN THERE.
TODAY...THE SHORTWAVE TROUGH OVER THE REGION WILL SOUTHEAST
THROUGH MISSOURI AND INTO KENTUCKY/TENNESSEE/GULF STATES.
NORTHWEST FLOW AND COLD AIR ADVECTION WILL CONTINUE. ANY LINGERING
SPRINKLES OR ISOLATED RAIN/MIX SHOULD BE ON THE WANE EARLY THIS
MORNING. THERE IS QUITE A BIT OF STRATUS TO THE NORTH AND THE
NORTH FLOW WOULD ADVECT THESE LOW AND MID CLOUDS SOUTHWARD THROUGH
THE DAY. THE CLOUDS SHOULD HANG AROUND THE LONGEST IN NORTHEAST
NEBRASKA AND WESTERN IOWA...WITH FEWER CLOUDS TOWARD FAIRBURY.
HIGHS ARE FORECAST TO TOP OUT IN THE 30S AND 40S. STRONGER WINDS
ALOFT WILL KEEP WINDS UP IN SOUTHEAST NEBRASKA AND SOUTHWEST
IOWA...HOWEVER SURFACE WINDS WILL BECOME LIGHT AND VARIABLE BY
EVENING AS SURFACE HIGH PRESSURE BUILDS IN.
THE OPERATIONAL MODELS ARE IN GOOD AGREEMENT THAT RIDGING WILL
BUILD INTO THE PLAINS TONIGHT. WARM AIR ADVECTION ENSUES AHEAD OF
THE NEXT SHORTWAVE TROUGH THAT PASSES THROUGH THE NORTHERN PLAINS
AND PARTS OF THE MISSOURI RIVER VALLEY FRIDAY. A LOW LEVEL JET
STRENGTHENS TO 40 KNOTS WITH BREEZY CONDITIONS AT THE SURFACE.
WARMER TEMPERATURES WITH HIGHS IN THE 50S AND 60S FOR FRIDAY WITH
INCREASING SOUTH WINDS TO 15 TO 30 MPH. THERE COULD BE SOME
SPRINKLES WITH THE WARM AIR ADVECTION FRIDAY...HOWEVER...THE
ORGANIZED PRECIPITATION SHOULD BE NORTH OF THE FORECAST AREA. THE
MID TROPOSPHERIC RIDGE AMPLIFIES OVER THE ROCKIES FRIDAY NIGHT AND
THE PLAINS SATURDAY. THIS ALLOWS SOME COOLING AIR TO WORK
IN...HOWEVER HIGHS ARE STILL FORECAST TO BE IN THE 50S.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 315 AM CST THU MAR 3 2016
MORE OF A SPRINGTIME PATTERN WITH STRONGER WINDS...WARMER
TEMPERATURES AND SCATTERED SHOWERS AND THUNDERSTORMS EARLY NEXT
WEEK.
AN IMPULSE MOVING ACROSS THE ROCKIES SATURDAY NIGHT BEGINS TO
BREAK DOWN THE RIDGE AND THIS CONTINUES SUNDAY. THE FLOW ALOFT IS
FROM THE SOUTHWEST AND AN ADDITIONAL SHORTWAVE TROF SWINGS THROUGH
THE ROCKIES AND WESTERN PLAINS MONDAY AND MONDAY NIGHT.
MEANWHILE...MONDAY THROUGH TUESDAY...CLOSED LOW PRESSURE OVER
CALIFORNIA TRACKS INTO MEXICO...WITH THE TROUGH ELONGATING
NORTHEASTWARD INTO THE PLAINS.
A STRENGTHENING LOW LEVEL JET TO AROUND 40KTS WILL TRANSPORT
MOISTURE NORTHWARD (6 TO 10DEG C DEWPOINT) WITH THE CHANCE FOR A
FEW SHOWERS OR THUNDERSTORMS IN SOUTHEAST NEBRASKA SUNDAY
AFTERNOON. HIGHS IN 50S AND 60S RETURN FOR SUNDAY. THE CHANCE FOR
THUNDERSTORMS CONTINUES SUNDAY NIGHT AND MONDAY AS THE SHORTWAVE
TROUGH OVER THE ROCKIES LIFT NORTHEAST INTO WESTERN NEBRASKA...AND
ALSO MONDAY NIGHT AS THE SURFACE FRONT PUSHES ACROSS THE FORECAST
AREA.
SURFACE WINDS LOOK STRONG MONDAY AND MONDAY NIGHT AND A WIND
ADVISORY MAY BE NEEDED.
SOME POST-FRONTAL PRECIPITATION COULD LINGER IN FAR SOUTHEAST
NEBRASKA TUESDAY NIGHT...HOWEVER LOOKS TO BE EAST OF THE AREA
WEDNESDAY. HIGHS MONDAY SHOULD RISE INTO THE 60S AND 70S. NOT AS
WARM TUESDAY WITH HIGHS IN THE 50S AND 60S...AND 50S FOR
WEDNESDAY.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 525 AM CST THU MAR 3 2016
ALL THREE TAF SITES HAD VFR CONDITIONS AS OF 11Z...BUT THIS WILL
LIKELY CHANGE. LOW LEVEL MOISTURE EXTENDED FROM NORTHWEST TO EAST
OF THE AREA...AND IT SHOULD MOVE SOUTHWARD. THE LOW CIGS IN IOWA
MAY BACK TO THE SOUTHWEST TOWARD OMAHA THIS MORNING...THEN LOOK
FOR MVFR CIGS AT ALL THREE SITES MUCH OF THE DAY. RECENT RAP MODEL
SOUNDINGS AND RH TIME SECTIONS SUGGEST LOW CLOUDS MAY LINGER WELL
INTO THE EVENING...BUT FOR NOW...DECIDED TO TREND TOWARD VFR BY
LATE AFTN OR EARLY EVENING. SOME FOG MAY DEVELOP OVERNIGHT...BUT
CONFIDENCE WAS NOT HIGH ENOUGH TO INCLUDE AT THIS TIME.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS ELKO NV
207 AM PST THU MAR 3 2016
.SYNOPSIS...PATTERN IS BEGINNING TO TRANSITION TO A WET AND COOLER
ONE WITH A COUPLE OF WEAK SYSTEMS BRINGING CLOUDS AND SHOWERS
THROUGH SATURDAY. A STRONGER AND COLDER SYSTEM IS ON TAP FOR
SUNDAY...FOLLOWED BY SEVERAL MORE NEXT WEEK.
&&
.SHORT TERM...THIS MORNING THROUGH SATURDAY.
PATTERN BEGINNING TO BECOME ACTIVE WITH A FRONTAL BOUNDARY ENTERING THE
CWA TODAY...FOLLOWED ANOTHER ONE EARLY SATURDAY. OVERALL STILL
ABOVE AVERAGE TEMPERATURES AS THE UPPER LEVEL FLOW REMAINS OUT OF
THE SOUTHWEST.
SPECIFICALLY..A COLD FRONT IS PROGRESSING EASTWARD WITH THE MAIN PRECIP
BAND JUST CROSSING INTO NV. 700-600MB FGEN NUMBERS ALONG WITH
METSAT INDICATES THAT THIS BAND WILL WEAKEN AS IT ENTERS HUMBOLDT
COUNTY EARLY THIS MORNING...BUT PROVIDE ENOUGH LIFT TO GENERATE
SHOWERS OVER MAINLY THE HIGHER TERRAIN. BY LATER THIS MORNING
ANOTHER WAVE WILL TRAVEL NORTHEAST ALONG THE FRONTAL
BOUNDARY...REDEVELOPING A FRONTAL BAND OF PRECIP OVER EASTERN
HUMBOLDT COUNTY AND NORTHWESTERN HALF OF ELKO COUNTY BY EARLY THIS
AFTERNOON. GFS...RAP...AND HRRR ALL PEG THIS NARROW BAND SO
BASICALLY WENT A BLEND FOR PLACEMENT BUT LIMITED THE POP AND QPF
BELOW THEIR MEANS AS THIS BAND MAY NOT DEVELOP AS STRONG AS THEY
INDICATE. ALSO...CANNOT RULE OUT A LIGHTNING STRIKE OR TWO...BUT
NOT ENOUGH CONFIDENCE TO INCLUDE IT IN THE FORECAST AT THIS TIME.
SOME HIGHER TERRAIN AREAS COULD PICK A QUICK .10 OF PRECIP DURING
THIS BRIEF PERIOD. SNOW LEVELS WILL RUNS WELL ABOVE THE VALLEYS
FLOOR SO NO IMPACTS EXPECTED. THIS BAND WILL WEAKEN QUITE QUICKLY
AS IT SHIFTS MAINLY EASTWARD...SPREADING THE BEST PRECIP CHANCES
OVER NORTHEASTERN NV...STRETCHING SOUTHWESTWARD TOWARDS BATTLE
MTN. AMOUNTS ARE NOT EXPECTED TO BE MORE THAN A COUPLE OF
HUNDREDTHS WITH THE EXCEPTION OF NORTHEASTERN ELKO COUNTY WHERE
MORE COULD FALL IN THE HIGHER TERRAIN. BY TONIGHT THIS BOUNDARY
PRETTY MUCH STALLS OUT JUST SOUTH I-80 AND LOOKS TO WEAKEN...BUT
DOES PROVIDE SOME LOW LEVEL CONVERGENCES TO GENERATE VERY ISOLATED
SHOWERS NEAR AND TO THE NORTH OF IT OVERNIGHT INTO EARLY FRIDAY
MORNING. ONCE AGAIN..PRECIP AMOUNTS WILL BE VERY LIGHT. SOME SHORT
RANGE MODELS INDICATE ANOTHER WAVE MAY TRAVEL NORTHEAST ALONG THE
BOUNDARY...STRENGTHENING IT AND FORMING A BAND OF PRECIP. CLOUD
COVER DECREASES TOMORROW AS A SHORTWAVE RIDGE QUICKLY BUILDS
OVERHEAD IN ADVANCE OF THE NEXT FRONTAL SYSTEM HITTING THE CA
COAST LATE FRIDAY. THIS BOUNDARY WILL ONCE AGAIN WEAKEN AS IT
LIFTS NORTHEAST IN WESTERN NV LATE FRIDAY NIGHT. THIS WILL SPREAD
PRECIP IN HUMBOLDT COUNTY SATURDAY MORNING...SHIFTING EASTWARD
SATURDAY AFTERNOON. POPS AND PRECIP AMOUNTS WILL QUICKLY DROP TO
OFF EAST AND SOUTH OF HUMBOLDT COUNTY AS BOUNDARY FALLS APART.
ONCE AGAIN SNOW LEVELS WILL RUN ABOVE 7500FT OR HIGHER SO NO
TRAVEL IMPACTS EXPECTED. SOUTHERLY WINDS WILL PICK UP SATURDAY
AHEAD OF THIS BOUNDARY BUT ALSO FROM THE OVERALL INCREASE IN
SOUTHWESTERLY WINDS ALOFT AHEAD OF A MUCH STRONGER FRONTAL SYSTEM
WITH A WELL DEFINE ATMOSPHERE RIVER THAT SPREADS HEAVY PRECIP INTO
NORTHERN CALIFORNIA SATURDAY AFTERNOON. WILL HAVE TO KEEP AN EYE
ON THE WINDS FOR LIKELY HEADLINES IN HUMBOLDT COUNTY FOR SATURDAY
AFTERNOON OR EVENING.
AS FOR TEMPS...WITH ABUNDANCE OF CLOUD COVER IN NORTHERN NV
TODAY...TEMPS WILL NOT CLIMB AS MUCH AS YESTERDAY...STILL 50S AND
60S WILL DOMINANT. TEMPS SHOULD DROP OFF OFF TONIGHT TO MAINLY THE
30S BEFORE CLIMBING BACK IN THE 50S AND 60S TOMORROW UNDER PARTLY
CLOUDY SKIES. WITH THE APPROACHING FRONTAL BOUNDARY TOMORROW
WESTERN AREAS WILL REMAIN WELL IN THE 30S TOMORROW NIGHT...WHILE
EASTERN NV FALLS BACK INTO THE 20S AND 30S. WITH INCREASE IN
SOUTHERLY OR SOUTHWESTERLY FLOW...TEMPS SHOULD EASILY CLIMB BACK
INTO THE 50S AND 60S ON SATURDAY.
.LONG TERM...SATURDAY NIGHT THROUGH NEXT WEDNESDAY. A MOIST LOW
PRESSURE SYSTEM WILL BRING AN EXTENDED PERIOD OF UNSETTLED
WEATHER...AND A DEFINITE CHANGE FROM RECENT MILD WEATHER. THE MODELS
ARE IN VERY GOOD AGREEMENT WITH THE TIMING OF A COLD FRONT ON SUNDAY.
SATURDAY NIGHT. HIGH PRESSURE WILL BROADEN TO ENCOMPASS THE ENTIRE
CENTRAL CONUS...BUT WILL YIELD TO A STRONG INCOMING TROUGH OF LOW
PRESSURE. A LOW PRESSURE SYSTEM WILL BE DROPPING DOWN FROM ALASKA
AND PUSHING A COPIOUS AMOUNT OF MOISTURE INTO CALIFORNIA AND WESTERN
NEVADA. NEVADA WILL BE UNDER A DIFFLUENT FLOW ALOFT. WITH THE
PERSISTENT MOISTENING FLOW ALOFT...SHOWERS SHOULD SPREAD TO MOST
AREAS BY SUNRISE SUNDAY HOWEVER THERE IS SOME QUESTION AS TO HOW
MUCH RAIN WILL REACH THE VALLEYS EAST OF HUMBOLDT COUNTY DUE TO THE
PURE SOUTHWEST FLOW ACROSS THE SIERRAS. SNOW LEVEL WILL BE DROPPING
TO AROUND 7500 FEET. EARLY MORNING LOWS WILL BE RELATIVELY
MILD...ABOVE FREEZING ALL AROUND.
SUNDAY. AN UPPER LOW CIRCULATION WILL TAKE OFF TO THE
NORTH...SKIRTING THE OREGON AND WASHINGTON COASTLINE...AND SPINNING
OFF A STRONG SHORTWAVE THAT WILL BLAST THROUGH NEVADA. A COLD FRONT
WILL BRING RAIN THAT WILL QUICKLY TURN TO SNOW IN THE VALLEYS. SNOW
LEVELS WILL START OUT AROUND 6500 FEET. ISOLATED THUNDERSTORMS WILL
BE POSSIBLE AND WIND GUSTS ON THE HIGHEST MOUNTAIN PEAKS MAY REACH
70 MPH AHEAD OF THE COLD FRONT. THE LATEST MODEL TIMING LOOKS LIKE
THIS...THE FRONT SHOULD MOVE THROUGH WINNEMUCCA ABOUT 4
AM...FOLLOWED BY ELKO ABOUT 8 AM...THEN ELY ABOUT 10 AM. AT THIS
JUNCTURE...SNOWFALL ESTIMATES ARE FIGURED TO BE HIGHER IN CENTRAL
NEVADA...AS MUCH AS ONE FOOT ON THE MOUNTAINS GENERALLY 2-4 INCHES
IN THE VALLEYS. IT IS POSSIBLE THAT AS MUCH AS 6 INCHES COULD FALL
IN THE VALLEYS OF WHITE PINE COUNTY. TEMPERATURES MAY START OUT IN
THE 40S EARLY IN THE DAY THEN FALL THROUGH THE 30S.
SUNDAY NIGHT THROUGH TUESDAY. SNOW SHOWERS WILL CONTINUE. THERE MAY
BE A SECONDARY COLD FRONT MOVING THROUGH ON MONDAY. HIGHS IN
THE 30S TO AROUND 40. LOWS IN THE TEENS AND 20S.
TUESDAY NIGHT THROUGH WEDNESDAY. AT THIS JUNCTURE...IT APPEARS THAT
A SHORTWAVE RIDGE WILL BRING DRIER CONDITIONS HOWEVER A FEW SHOWERS
MAY PERSIST ACROSS NORTHERN NEVADA. HIGHS IN THE 30S TO AROUND 40.
LOWS IN THE TEENS AND 20S.
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED TO HOLD THROUGH FRIDAY
MORNING. HOWEVER HIGH PRESSURE WILL BE MOVING EAST OF NEVADA THIS
MORNING AND SHOWERS WILL BE DEVELOPING OVER THE NORTHERN PART OF THE
STATE AS A LOW PRESSURE SYSTEM APPROACHES FROM THE WEST. VCSH IS
POSSIBLE AT KWMC THURSDAY AFTERNOON.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
85/92/85
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 PM EST THU MAR 3 2016
.SYNOPSIS... AN AREA OF LOW PRESSURE TRACKING EAST ACROSS THE GULF
COAST STATES WILL QUICKLY NORTHEAST UP THE NC COAST OVERNIGHT AND
OFF THE MID-ATLANTIC COAST ON FRIDAY. HIGH PRESSURE WILL BUILD INTO
THE AREA FRIDAY NIGHT AND SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM THURSDAY...
...A LIGHT WINTRY MIX POSSIBLE ACROSS THE NORTHERN PIEDMONT TONIGHT...
HIGH PRESSURE CURRENTLY CENTERED OVER THE DELMARVA IS SHIFTING
OFFSHORE THIS AFTERNOON. WINDS WILL CONTINUE TO BECOME MORE EAST-
SOUTHEASTERLY AND DEWPOINTS WILL RECOVER INTO THE UPPER 20S AND 30S.
IT IS WORTH NOTING THAT DEWPOINTS ARE SLIGHTLY LOWER
THAN FORECAST RIGHT NOW. MEANWHILE...A LOW AMPLITUDE SHORTWAVE AND
ASSOCIATED SURFACE LOW TRACKING THROUGH THE MID-SOUTH WILL TRACK
ACROSS AL/GA THIS EVENING AND TO THE NC COAST BY LATE TONIGHT. RAIN
IS CURRENTLY MOVING INTO UPSTATE SC...THOUGH IT WILL INITIALLY GO
TOWARD SATURATED THE DRY BOUNDARY LAYER AND SET UP A HYBRID CAD
AIRMASS. LIFT REALLY STARTS TO STRENGTHEN AFTER 21Z AS THE WARM
CONVEYOR BELT AND DEEPENING ISENTROPIC LIFT SHIFT OVERHEAD. THE
HEAVIEST QPF WILL FOCUS ACROSS THE SOUTHERN PIEDMONT TO THE COASTAL
PLAIN ALONG AND JUST NORTH OF THE SURFACE LOW...WITH ADDITIONAL
LIGHTER PRECIP EXPECTED TO BREAK OUT OVER THE PIEDMONT AS A
DEFORMATION BAND FORMS NORTHWEST OF THE PASSING LOW. LOW TEMPS
TONIGHT WILL BE IN THE 32-39 RANGE.
THE ONSET OF PRECIP MAY EVERY WELL COME IN FORM OF RAIN WITH SLEET
OR PARTIALLY MELTED SNOW MIXED IN THIS EVENING...MAINLY ACROSS THE
WESTERN PIEDMONT WHERE WET-BULB PROFILES ARE A BIT COOLER. AREAS
SOUTH OF HIGHWAY 64 WILL BE MUCH TOO WARM BELOW 5000 FT FOR ANY NON-
LIQUID PTYPES TONIGHT. CRITICAL THICKNESSES IN THE NORTHERN PIEDMONT
(AND WITHIN THE DEFORMATION BAND ARE GENERALLY IN THE 1300-1310M
(H10-H85) AND SUB-1540M (H85-H7)...WHICH SUPPORTS A MIX OF PTYPES.
THE BIGGEST QUESTIONS THAT STILL REMAIN...AND LEAD US TO REFRAIN
FROM A WINTER WX ADVISORY...ARE WHETHER OR NOT SNOW/SLEET WILL BE
THE PREDOMINATE PTYPE FOR A DECENT DURATION. MODELS SHOW PRETTY
RAPID DRYING ABOVE -10C AFTER 06Z...WHICH WILL SHUT OFF THE THE
MIXING OF SNOW. ALSO...WETBULB TEMPS ARE PROGGED TO REMAIN ABOVE
FREEZING THROUGH THE EVENT...SO SNOW SHOULD NOT READILY
ACCUMULATE...EXCEPT MAYBE ON ELEVATED SURFACES. FINALLY...THE
LATEST HRRR HAS SHIFTED THE NORTHWEST EDGE OF THE PRECIP SHIELD TO
THE EAST...A TREND ALSO NOTED IN THE 12Z WRF-ARW.
CONCERNS FOR ACCUMULATING SNOW ARE 1)MODELS UNDERDOING PRECIP RATES
WHERE THERMAL PROFILES ARE MARGINAL AND 2) DRIER LOW-LEVEL AIR OVER
EAST-CENTRAL VA COULD BE TAPPED THIS EVENING AS WINDS SWING BACK TO
NORTH-NORTHEASTERLY IN RESPONSE TO THE SURFACE LOW ALONG THE
COAST...CREATING LOWER WETBULB VALUES.
WITH ALL OF THIS IN MIND...CONFIDENCE IN GREATER THAN 1 INCH OF SNOW
AND/OR TRAVEL IMPACTS IS TOO LOW TO ISSUE AN ADVISORY.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
AS OF 300 PM THURSDAY...
PRECIP WILL BE EXITING THE COASTAL PLAIN FRIDAY MORNING ALONG WITH
HE SURFACE LOW. SUBSIDENCE AND AND NORTHWESTERLY FLOW WILL CLEAR
SKIES FROM WEST TO EAST...ALLOWING TEMPS INT HE WESTERN PIEDMONT TO
CLIMB INTO THE 50S...WHILE AREAS EAST OF US 1 WILL HOLD ONTO CLOUDS
A BIT LONGER AND MAY STAY IN THE MID/UPPER 40S. HIGH PRESSURE WILL
BEGIN TO BUILD OVERHEAD FRIDAY NIGHT...WITH CLEARING SKIES...THOUGH
SOME LINGERING MOISTURE UPSTREAM MAY RESULT IN PATCHY STRATO CU
DRIFTING ACROSS THE PIEDMONT EARLY. OTHERWISE...GOOD RADIATIONAL
POOLING CONDITIONS SHOULD RESULT IN LOWER 30S FOR LOWS.
&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 228 PM THURSDAY...
THROUGH SAT NIGHT: HIGH PRESSURE WILL PASS OVERHEAD SAT...SHIFTING
OFFSHORE SAT EVE/NIGHT. HIGHS GENERALLY IN THE MID 50S WITH WEAK
WINDS BACKING TO SOUTHERLY BY SAT AFT/EVE. A SHORT WAVE ALOFT AND
ASSOCIATED SURFACE LOW WILL DIVE SOUTHEAST FROM THE WESTERN GREAT
LAKES INTO THE MID ATLANTIC SAT NIGHT. THE CHANCE FOR SOME LIGHT
RAIN AS THE SHORTWAVE PASSES OVERHEAD CONTINUES TO INCREASE...
HOWEVER AMOUNTS ARE EXPECTED TO BE FAIRLY LIGHT. LOWS SAT NIGHT IN
THE MID 30S TO LOW 40S.
SUN THROUGH THU: SURFACE HIGH PRESSURE WILL BUILD INTO AND OVER THE
REGION THROUGH TUESDAY...SHIFTING OFFSHORE BUT CONTINUING TO RIDGE
WESTWARD FROM THE ATLANTIC WED AND THU RESULTING IN A SOUTHERLY
RETURN FLOW OVER CENTRAL NC. ANOTHER POTENT LOW PRESSURE SYSTEM
APPROACHES FROM THE WEST MID-WEEK. AMPLIFYING THE RIDGE OVER THE SE
U.S. AS IT DOES. THE RESULT WILL BE DEEPENING SOUTHERLY FLOW OVER
CENTRAL NC AND INCREASING WINDS AT THE SURFACE. THERE WILL BE PLENTY
OF SUNSHINE SUN AND MON...WITH GRADUALLY INCREASING HIGH CLOUDS
THROUGH MID WEEK AHEAD OF THE AFOREMENTIONED SYSTEM. WITH THE
INCREASING WARM ADVECTION...TEMPS WILL MODERATE FROM SUN (HIGHS IN
THE MID 50S TO LOW 60S AND LOWS IN THE LOW TO MID 30S) THROUGH THU
(HIGHS IN THE LOW TO MID 70S AND LOWS IN THE MID 50S). FOR NOW THE
MODELS SUGGEST ANY PRECIPITATION WILL HOLD OFF UNTIL THU AFT/EVE OR
LATER. WILL INTRODUCE A SLIGHT CHANCE OF SHOWERS ACROSS THE NORTH
THU AFTERNOON. OTHERWISE...WILL KEEP THE FORECAST DRY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 100 PM THURSDAY...
HIGH PRESSURE CURRENTLY OVER THE DELMARVA WILL SHIFT OFFSHORE THIS
AFTERNOON AND WINDS WILL BECOME MORE SOUTHEASTERLY AHEAD OF A LOW
PRESSURE SYSTEM TRACKING INTO THE MID SOUTH. AS THE SYSTEM
APPROACHES...MID-LEVEL CEILINGS WILL LOWER TO MVFR AND EVENTUALLY
IFR AS RAIN OVERSPREADS THE AREA. KINT/KGSO/KFAY SHOULD SEE MVFR BY
00Z...AT KRDU/KRWI BY 03Z. IFR CONDITIONS WILL FOLLOW IN THE 03-07Z
TIME FRAME. RAIN MAY BE BRIEFLY HEAVY AT KFAY...WHILE SNOW MAY MIX
IN WITH THE RAIN AT KGSO/KINT.
PRECIP WILL END FROM WEST TO EAST FRIDAY MORNING AS THE LOW PRESSURE
MOVES TO NEAR THE OBX BY 12Z. NORTHERLY WINDS WILL STRENGTHEN TO 12-
15KT AT KRWI...WITH NORTHWESTERLY WINDS EVENTUALLY DEVELOPING ACROSS
THE ENTIRE AREA AND GUSTING TO 15-18KT AS SKIES CLEAR.
OUTLOOK: VFR CONDITIONS SHOULD DOMINATE THROUGH EARLY NEXT WEEK. THE
EXCEPTION WILL BE SATURDAY NIGHT/EARLY SUNDAY MORNING WHEN A STRONG
UPPER LEVEL DISTURBANCE WILL TRACK ACROSS THE REGION AND BRING A
CHANCE OF SUB-VFR CONDITIONS AND LIGHT RAIN.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...22
SHORT TERM...22
LONG TERM...10
AVIATION...CBL/22
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1142 AM CST THU MAR 3 2016
.UPDATE...
ISSUED AT 1136 AM CST THU MAR 3 2016
NO SIGNIFICANT CHANGE TO THE ONGOING FORECAST OTHER THAN TO BLEND
TO OBSERVED TRENDS THROUGH 17 UTC. EXPECT THE STRATUS TO HOLD
ACROSS NORTH DAKOTA THROUGH THE REMAINDER OF THE DAY AND INTO THE
NIGHT WITH LOW LEVEL WARM AIR ADVECTION REINFORCING THE LOW LEVEL
INVERSION UNTIL GREATER MIXING SCOURS OUT THE LOW LEVEL MOISTURE
BEHIND THE COLD FRONT TONIGHT INTO FRIDAY MORNING.
UPDATE ISSUED AT 931 AM CST THU MAR 3 2016
CURRENT FORECAST IS ON TRACK AS PARTS OF THE NORTH CENTRAL
CONTINUE TO SHOW LIGHT SNOW AND VISIBILITY IN DICKINSON HAS RISEN
TO 5 MILES ALONG WITH VISIBILITIES AT ALL OTHER SITES ACROSS THE
SOUTHWEST.
UPDATE ISSUED AT 636 AM CST THU MAR 3 2016
WE ADDED ISOLATED FLURRIES TO THE FORECAST FROM CROSBY EASTWARD TO
BOTTINEAU...ROLLA AND RUGBY THROUGH THE MORNING WITH THIS UPDATE.
THAT CHANGE WAS PREDICATED BY WEAK RADAR ECHOES AROUND ROLLA WITH
FLURRIES REPORTED AT ROLLA AND ESTEVAN...AND SUBTLE HINTS OF SAID
ACTIVITY OVER NORTH CENTRAL ND WITH RECENT HRRR RUNS. THE REST OF
THE FORECAST IS GENERALLY ON TRACK. FOG OVER SOUTHWESTERN ND HAS
OCCASIONALLY BEEN REDUCING THE VISIBILITY TO 1/2SM AT DICKINSON.
HOWEVER...SUB-1SM TYPE OF VISIBILITIES HAVE NOT BEEN WIDESPREAD.
THAT IS LIKELY DUE TO A SHALLOW MIXED LAYER STILL PRESENT AT THE
SURFACE PER MODEL FORECAST SOUNDINGS /AND CONFIRMED BY THE 12 UTC
OBSERVED SOUNDING AT BISMARCK/.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CST THU MAR 3 2016
THE MAIN FOCUS FOR THE SHORT TERM IS FOG AND CLOUD COVER TODAY AND
FREEZING RAIN POTENTIAL TONIGHT.
A VERY MOIST BOUNDARY LAYER AND EASTERLY UPSLOPING WINDS WILL KEEP
MOST OF NORTH DAKOTA SOCKED IN UNDER LOW STRATUS AND PATCHY FOG
MOST OF THE DAY. WARM AIR ADVECTION AND SOUTHWESTERLY FLOW AT THE
SURFACE WILL BEGIN LATE THIS AFTERNOON ACROSS SOUTHWEST NORTH
DAKOTA AHEAD OF AN APPROACHING CLIPPER. THIS WILL BEGIN TO ERODE
THE LOW STRATUS.
TONIGHT...A CLIPPER WILL SWING THROUGH NORTH DAKOTA BRINGING A
CHANCE FOR SOME LIGHT PRECIPITATION. MODELS ARE INDICATING A WARM
LAYER AROUND 850MB BEING ADVECTED IN ALONG THE LEADING EDGE OF THE
SURFACE LOW. THIS WARMER AIR SHOULD BE SUFFICIENT TO MELT ANY ICE
CRYSTALS THAT FALL ALOFT. DUE TO THE TIMING OF THIS SYSTEM (DURING
THE OVERNIGHT AND EARLY MORNING HOURS) SURFACE TEMPERATURES WILL
BE BELOW FREEZING. THIS COULD LEAD TO SOME LIGHT FREEZING RAIN FOR
PORTIONS OF CENTRAL AND EASTERN NORTH DAKOTA. THERE IS SOME
UNCERTAINTY AND DISPARITY BETWEEN THE MODELS ON EXACTLY HOW MUCH
PRECIPITATION COULD FALL. SOME MODELS ARE ALMOST COMPLETELY DRY
WITH THE PASSING OF THE LOW...WHILE OTHER MODELS BRING IN A FEW
HUNDRETHS OF PRECIPITATION. ONLY A LITTLE BIT OF MOISTURE COULD
CAUSE SOME SLICK CONDITIONS SO THIS SITUATION WILL BE CLOSELY
MONITORED. AT THIS TIME WE DON`T FEEL CONFIDENT ENOUGH GIVEN THE
UNCERTAINTY IN THE DIFFERENT MODEL SOLUTIONS TO ISSUE ANY
HEADLINES OR HIGHLIGHT THIS THREAT ANY FURTHER THAN THE HAZARDOUS
WEATHER OUTLOOK AND WEATHER STORY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 342 AM CST THU MAR 3 2016
A MILD AND WINDY FRIDAY WILL BE FOLLOWED BY A VERY WARM WEEKEND
AND AN INCREASING CHANCE OF PRECIPITATION MONDAY AND TUESDAY.
A SLIGHT CHANCE OF LIGHT FREEZING RAIN CONTINUES THROUGH 15 UTC
FRIDAY MORNING OVER EAST CENTRAL ND...BUT WILL ABRUPTLY END AS
ANY PRECIPITATION EXITS THE AREA AND SURFACE TEMPERATURES RISE
ABOVE 32 F. A COLD FRONT WILL CROSS THE AREA FRIDAY MORNING AND
LOW-LEVEL NORTHWEST FLOW WILL INCREASE IN ITS WAKE WITH THE GFS
RUN FROM 00 UTC SIMULATING BOUNDARY LAYER WINDS AROUND 30 KT ON
FRIDAY. PRESSURE RISES ARE NOT MUCH TO WRITE HOME ABOUT AT ONLY
2-3 MB/3 HOURS ON THE GFS /AND LESS ON THE 00 UTC NAM/ AND PEAK
WINDS AT THE TOP OF THE WELL-MIXED LAYER FRIDAY AFTERNOON BASED
ON FORECAST SOUNDINGS ARE GENERALLY UNDER 40 KT. THUS...WHILE A
WINDY DAY IS EXPECTED...SPEEDS WILL LIKELY STAY UNDER ADVISORY
CRITERIA IF TRENDS IN THE 00 UTC GUIDANCE SUITE ARE CORRECT.
ON THE LARGE SCALE...HEIGHTS WILL BUILD ALOFT ACROSS THE REGION
THIS WEEKEND DOWNSTREAM OF A POWERFUL PACIFIC JET THAT WILL DIG
INTO THE WESTERN UNITED STATES...CARVING OUT A 500-MB TROUGH BY
EARLY NEXT WEEK. GLOBAL MODEL GUIDANCE HAS BEEN STEADFAST IN ITS
PREDICTION OF THESE KEY FEATURES THE LAST SEVERAL DAYS...RAISING
OUR CONFIDENCE IN A VERY WARM WEEKEND BENEATH THE RIDGING ALOFT.
IN FACT...WE WEIGHTED THE FORECAST A BIT TOWARD THE WARMER EDGE
OF THE 00 UTC GUIDANCE GIVEN THE BREADTH OF EXPECTED WARM AIR
ADVECTION AND MIXING...WITH WIDESPREAD 50S AND LOWER 60S F OVER
MOST OF THE AREA ON SATURDAY...AND MANY 60S F LIKELY ON SUNDAY.
IT WILL BE BREEZY...ESPECIALLY ON SATURDAY...PERHAPS ELEVATING
THE RISK OF GRASS FIRES A BIT THIS WEEKEND TOO.
BY MONDAY AND TUESDAY...A LEAD NORTHERN-STREAM SHORTWAVE TROUGH
IS FORECAST TO EJECT INTO THE NORTHERN PLAINS OUT OF THE THEN-
SPLITTING LONGWAVE TROUGH. HOWEVER...THE PREDICTABILITY OF ITS
EVOLUTION IS LOW...SO FOR NOW WE ARE MERELY ADVERTISING CHANCE
POPS AND A COOLING TREND IN THE MONDAY AND TUESDAY FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1136 AM CST THU MAR 3 2016
WIDESPREAD IFR/MVFR CEILINGS IN STRATUS WILL SLOWLY LIFT THROUGH
THE AFTERNOON ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
HOWEVER...STRATUS BUILD DOWN TO WIDESPREAD IFR IS EXPECTED AGAIN
THIS EVENING AND TONIGHT. A COLD FRONT WILL MOVE ACROSS NORTH
DAKOTA LATE TONIGHT INTO FRIDAY MORNING. NORTHWEST WIND GUSTS OF
25-30 KTS ARE EXPECTED BEHIND THE FRONT WITH IMPROVING CEILINGS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...AJ
LONG TERM...CJS
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
938 AM CST THU MAR 3 2016
.UPDATE...
ISSUED AT 931 AM CST THU MAR 3 2016
CURRENT FORECAST IS ON TRACK AS PARTS OF THE NORTH CENTRAL
CONTINUE TO SHOW LIGHT SNOW AND VISIBILITY IN DICKINSON HAS RISEN
TO 5 MILES ALONG WITH VISIBILITIES AT ALL OTHER SITES ACROSS THE
SOUTHWEST.
UPDATE ISSUED AT 636 AM CST THU MAR 3 2016
WE ADDED ISOLATED FLURRIES TO THE FORECAST FROM CROSBY EASTWARD TO
BOTTINEAU...ROLLA AND RUGBY THROUGH THE MORNING WITH THIS UPDATE.
THAT CHANGE WAS PREDICATED BY WEAK RADAR ECHOES AROUND ROLLA WITH
FLURRIES REPORTED AT ROLLA AND ESTEVAN...AND SUBTLE HINTS OF SAID
ACTIVITY OVER NORTH CENTRAL ND WITH RECENT HRRR RUNS. THE REST OF
THE FORECAST IS GENERALLY ON TRACK. FOG OVER SOUTHWESTERN ND HAS
OCCASIONALLY BEEN REDUCING THE VISIBILITY TO 1/2SM AT DICKINSON.
HOWEVER...SUB-1SM TYPE OF VISIBILITIES HAVE NOT BEEN WIDESPREAD.
THAT IS LIKELY DUE TO A SHALLOW MIXED LAYER STILL PRESENT AT THE
SURFACE PER MODEL FORECAST SOUNDINGS /AND CONFIRMED BY THE 12 UTC
OBSERVED SOUNDING AT BISMARCK/.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CST THU MAR 3 2016
THE MAIN FOCUS FOR THE SHORT TERM IS FOG AND CLOUD COVER TODAY AND
FREEZING RAIN POTENTIAL TONIGHT.
A VERY MOIST BOUNDARY LAYER AND EASTERLY UPSLOPING WINDS WILL KEEP
MOST OF NORTH DAKOTA SOCKED IN UNDER LOW STRATUS AND PATCHY FOG
MOST OF THE DAY. WARM AIR ADVECTION AND SOUTHWESTERLY FLOW AT THE
SURFACE WILL BEGIN LATE THIS AFTERNOON ACROSS SOUTHWEST NORTH
DAKOTA AHEAD OF AN APPROACHING CLIPPER. THIS WILL BEGIN TO ERODE
THE LOW STRATUS.
TONIGHT...A CLIPPER WILL SWING THROUGH NORTH DAKOTA BRINGING A
CHANCE FOR SOME LIGHT PRECIPITATION. MODELS ARE INDICATING A WARM
LAYER AROUND 850MB BEING ADVECTED IN ALONG THE LEADING EDGE OF THE
SURFACE LOW. THIS WARMER AIR SHOULD BE SUFFICIENT TO MELT ANY ICE
CRYSTALS THAT FALL ALOFT. DUE TO THE TIMING OF THIS SYSTEM (DURING
THE OVERNIGHT AND EARLY MORNING HOURS) SURFACE TEMPERATURES WILL
BE BELOW FREEZING. THIS COULD LEAD TO SOME LIGHT FREEZING RAIN FOR
PORTIONS OF CENTRAL AND EASTERN NORTH DAKOTA. THERE IS SOME
UNCERTAINTY AND DISPARITY BETWEEN THE MODELS ON EXACTLY HOW MUCH
PRECIPITATION COULD FALL. SOME MODELS ARE ALMOST COMPLETELY DRY
WITH THE PASSING OF THE LOW...WHILE OTHER MODELS BRING IN A FEW
HUNDRETHS OF PRECIPITATION. ONLY A LITTLE BIT OF MOISTURE COULD
CAUSE SOME SLICK CONDITIONS SO THIS SITUATION WILL BE CLOSELY
MONITORED. AT THIS TIME WE DON`T FEEL CONFIDENT ENOUGH GIVEN THE
UNCERTAINTY IN THE DIFFERENT MODEL SOLUTIONS TO ISSUE ANY
HEADLINES OR HIGHLIGHT THIS THREAT ANY FURTHER THAN THE HAZARDOUS
WEATHER OUTLOOK AND WEATHER STORY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 342 AM CST THU MAR 3 2016
A MILD AND WINDY FRIDAY WILL BE FOLLOWED BY A VERY WARM WEEKEND
AND AN INCREASING CHANCE OF PRECIPITATION MONDAY AND TUESDAY.
A SLIGHT CHANCE OF LIGHT FREEZING RAIN CONTINUES THROUGH 15 UTC
FRIDAY MORNING OVER EAST CENTRAL ND...BUT WILL ABRUPTLY END AS
ANY PRECIPITATION EXITS THE AREA AND SURFACE TEMPERATURES RISE
ABOVE 32 F. A COLD FRONT WILL CROSS THE AREA FRIDAY MORNING AND
LOW-LEVEL NORTHWEST FLOW WILL INCREASE IN ITS WAKE WITH THE GFS
RUN FROM 00 UTC SIMULATING BOUNDARY LAYER WINDS AROUND 30 KT ON
FRIDAY. PRESSURE RISES ARE NOT MUCH TO WRITE HOME ABOUT AT ONLY
2-3 MB/3 HOURS ON THE GFS /AND LESS ON THE 00 UTC NAM/ AND PEAK
WINDS AT THE TOP OF THE WELL-MIXED LAYER FRIDAY AFTERNOON BASED
ON FORECAST SOUNDINGS ARE GENERALLY UNDER 40 KT. THUS...WHILE A
WINDY DAY IS EXPECTED...SPEEDS WILL LIKELY STAY UNDER ADVISORY
CRITERIA IF TRENDS IN THE 00 UTC GUIDANCE SUITE ARE CORRECT.
ON THE LARGE SCALE...HEIGHTS WILL BUILD ALOFT ACROSS THE REGION
THIS WEEKEND DOWNSTREAM OF A POWERFUL PACIFIC JET THAT WILL DIG
INTO THE WESTERN UNITED STATES...CARVING OUT A 500-MB TROUGH BY
EARLY NEXT WEEK. GLOBAL MODEL GUIDANCE HAS BEEN STEADFAST IN ITS
PREDICTION OF THESE KEY FEATURES THE LAST SEVERAL DAYS...RAISING
OUR CONFIDENCE IN A VERY WARM WEEKEND BENEATH THE RIDGING ALOFT.
IN FACT...WE WEIGHTED THE FORECAST A BIT TOWARD THE WARMER EDGE
OF THE 00 UTC GUIDANCE GIVEN THE BREADTH OF EXPECTED WARM AIR
ADVECTION AND MIXING...WITH WIDESPREAD 50S AND LOWER 60S F OVER
MOST OF THE AREA ON SATURDAY...AND MANY 60S F LIKELY ON SUNDAY.
IT WILL BE BREEZY...ESPECIALLY ON SATURDAY...PERHAPS ELEVATING
THE RISK OF GRASS FIRES A BIT THIS WEEKEND TOO.
BY MONDAY AND TUESDAY...A LEAD NORTHERN-STREAM SHORTWAVE TROUGH
IS FORECAST TO EJECT INTO THE NORTHERN PLAINS OUT OF THE THEN-
SPLITTING LONGWAVE TROUGH. HOWEVER...THE PREDICTABILITY OF ITS
EVOLUTION IS LOW...SO FOR NOW WE ARE MERELY ADVERTISING CHANCE
POPS AND A COOLING TREND IN THE MONDAY AND TUESDAY FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 636 AM CST THU MAR 3 2016
MVFR/IFR CIGS ACROSS THE TERMINALS UNTIL LATE AFTERNOON AND
THIS EVENING. AREAS OF FOG ALSO EXPECTED INTO MID MORNING
THURSDAY ESPECIALLY AT KDIK WITH IFR VSBYS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MM
SHORT TERM...AJ
LONG TERM...CJS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS BISMARCK ND
636 AM CST THU MAR 3 2016
.UPDATE...
ISSUED AT 636 AM CST THU MAR 3 2016
WE ADDED ISOLATED FLURRIES TO THE FORECAST FROM CROSBY EASTWARD TO
BOTTINEAU...ROLLA AND RUGBY THROUGH THE MORNING WITH THIS UPDATE.
THAT CHANGE WAS PREDICATED BY WEAK RADAR ECHOES AROUND ROLLA WITH
FLURRIES REPORTED AT ROLLA AND ESTEVAN...AND SUBTLE HINTS OF SAID
ACTIVITY OVER NORTH CENTRAL ND WITH RECENT HRRR RUNS. THE REST OF
THE FORECAST IS GENERALLY ON TRACK. FOG OVER SOUTHWESTERN ND HAS
OCCASIONALLY BEEN REDUCING THE VISIBILITY TO 1/2SM AT DICKINSON.
HOWEVER...SUB-1SM TYPE OF VISIBILITIES HAVE NOT BEEN WIDESPREAD.
THAT IS LIKELY DUE TO A SHALLOW MIXED LAYER STILL PRESENT AT THE
SURFACE PER MODEL FORECAST SOUNDINGS /AND CONFIRMED BY THE 12 UTC
OBSERVED SOUNDING AT BISMARCK/.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CST THU MAR 3 2016
THE MAIN FOCUS FOR THE SHORT TERM IS FOG AND CLOUD COVER TODAY AND
FREEZING RAIN POTENTIAL TONIGHT.
A VERY MOIST BOUNDARY LAYER AND EASTERLY UPSLOPING WINDS WILL KEEP
MOST OF NORTH DAKOTA SOCKED IN UNDER LOW STRATUS AND PATCHY FOG
MOST OF THE DAY. WARM AIR ADVECTION AND SOUTHWESTERLY FLOW AT THE
SURFACE WILL BEGIN LATE THIS AFTERNOON ACROSS SOUTHWEST NORTH
DAKOTA AHEAD OF AN APPROACHING CLIPPER. THIS WILL BEGIN TO ERODE
THE LOW STRATUS.
TONIGHT...A CLIPPER WILL SWING THROUGH NORTH DAKOTA BRINGING A
CHANCE FOR SOME LIGHT PRECIPITATION. MODELS ARE INDICATING A WARM
LAYER AROUND 850MB BEING ADVECTED IN ALONG THE LEADING EDGE OF THE
SURFACE LOW. THIS WARMER AIR SHOULD BE SUFFICIENT TO MELT ANY ICE
CRYSTALS THAT FALL ALOFT. DUE TO THE TIMING OF THIS SYSTEM (DURING
THE OVERNIGHT AND EARLY MORNING HOURS) SURFACE TEMPERATURES WILL
BE BELOW FREEZING. THIS COULD LEAD TO SOME LIGHT FREEZING RAIN FOR
PORTIONS OF CENTRAL AND EASTERN NORTH DAKOTA. THERE IS SOME
UNCERTAINTY AND DISPARITY BETWEEN THE MODELS ON EXACTLY HOW MUCH
PRECIPITATION COULD FALL. SOME MODELS ARE ALMOST COMPLETELY DRY
WITH THE PASSING OF THE LOW...WHILE OTHER MODELS BRING IN A FEW
HUNDRETHS OF PRECIPITATION. ONLY A LITTLE BIT OF MOISTURE COULD
CAUSE SOME SLICK CONDITIONS SO THIS SITUATION WILL BE CLOSELY
MONITORED. AT THIS TIME WE DON`T FEEL CONFIDENT ENOUGH GIVEN THE
UNCERTAINTY IN THE DIFFERENT MODEL SOLUTIONS TO ISSUE ANY
HEADLINES OR HIGHLIGHT THIS THREAT ANY FURTHER THAN THE HAZARDOUS
WEATHER OUTLOOK AND WEATHER STORY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 342 AM CST THU MAR 3 2016
A MILD AND WINDY FRIDAY WILL BE FOLLOWED BY A VERY WARM WEEKEND
AND AN INCREASING CHANCE OF PRECIPITATION MONDAY AND TUESDAY.
A SLIGHT CHANCE OF LIGHT FREEZING RAIN CONTINUES THROUGH 15 UTC
FRIDAY MORNING OVER EAST CENTRAL ND...BUT WILL ABRUPTLY END AS
ANY PRECIPITATION EXITS THE AREA AND SURFACE TEMPERATURES RISE
ABOVE 32 F. A COLD FRONT WILL CROSS THE AREA FRIDAY MORNING AND
LOW-LEVEL NORTHWEST FLOW WILL INCREASE IN ITS WAKE WITH THE GFS
RUN FROM 00 UTC SIMULATING BOUNDARY LAYER WINDS AROUND 30 KT ON
FRIDAY. PRESSURE RISES ARE NOT MUCH TO WRITE HOME ABOUT AT ONLY
2-3 MB/3 HOURS ON THE GFS /AND LESS ON THE 00 UTC NAM/ AND PEAK
WINDS AT THE TOP OF THE WELL-MIXED LAYER FRIDAY AFTERNOON BASED
ON FORECAST SOUNDINGS ARE GENERALLY UNDER 40 KT. THUS...WHILE A
WINDY DAY IS EXPECTED...SPEEDS WILL LIKELY STAY UNDER ADVISORY
CRITERIA IF TRENDS IN THE 00 UTC GUIDANCE SUITE ARE CORRECT.
ON THE LARGE SCALE...HEIGHTS WILL BUILD ALOFT ACROSS THE REGION
THIS WEEKEND DOWNSTREAM OF A POWERFUL PACIFIC JET THAT WILL DIG
INTO THE WESTERN UNITED STATES...CARVING OUT A 500-MB TROUGH BY
EARLY NEXT WEEK. GLOBAL MODEL GUIDANCE HAS BEEN STEADFAST IN ITS
PREDICTION OF THESE KEY FEATURES THE LAST SEVERAL DAYS...RAISING
OUR CONFIDENCE IN A VERY WARM WEEKEND BENEATH THE RIDGING ALOFT.
IN FACT...WE WEIGHTED THE FORECAST A BIT TOWARD THE WARMER EDGE
OF THE 00 UTC GUIDANCE GIVEN THE BREADTH OF EXPECTED WARM AIR
ADVECTION AND MIXING...WITH WIDESPREAD 50S AND LOWER 60S F OVER
MOST OF THE AREA ON SATURDAY...AND MANY 60S F LIKELY ON SUNDAY.
IT WILL BE BREEZY...ESPECIALLY ON SATURDAY...PERHAPS ELEVATING
THE RISK OF GRASS FIRES A BIT THIS WEEKEND TOO.
BY MONDAY AND TUESDAY...A LEAD NORTHERN-STREAM SHORTWAVE TROUGH
IS FORECAST TO EJECT INTO THE NORTHERN PLAINS OUT OF THE THEN-
SPLITTING LONGWAVE TROUGH. HOWEVER...THE PREDICTABILITY OF ITS
EVOLUTION IS LOW...SO FOR NOW WE ARE MERELY ADVERTISING CHANCE
POPS AND A COOLING TREND IN THE MONDAY AND TUESDAY FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 636 AM CST THU MAR 3 2016
MVFR/IFR CIGS ACROSS THE TERMINALS UNTIL LATE AFTERNOON AND
THIS EVENING. AREAS OF FOG ALSO EXPECTED INTO MID MORNING
THURSDAY ESPECIALLY AT KDIK WITH IFR VSBYS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...AJ
LONG TERM...CJS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
706 AM EST THU MAR 3 2016
.SYNOPSIS...
LINGERING SNOW SHOWERS AND FLURRIES WILL GIVE WAY TO FAIR WEATHER
LATER TODAY. A WIDESPREAD LIGHT SNOW ACCUMULATION OF 1 TO 2
INCHES IS EXPECTED TONIGHT INTO FRIDAY MORNING. ADDITIONAL LIGHT
SNOW IS POSSIBLE SATURDAY EVENING INTO EARLY SUNDAY. THE FORECAST
FOR NEXT WEEK LOOKS MILD WITH HIGH CONFIDENCE IN ABOVE NORMAL
TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
IR SATELLITE AND RADAR TRENDS SHOW DECREASING COVERAGE OF LAKE
STRATOCU AND SNOW SHOWERS/FLURRIES. MOST AREAS WILL SEE SUNSHINE
THIS MORNING BEFORE CLOUDS INCREASE FROM THE WEST AND THICKEN
THROUGH THE AFTERNOON.
SHORTWAVE DIGGING SOUTHEAST INTO THE MID MS VALLEY THIS MORNING
WILL MOVE THROUGH THE TN VALLEY TODAY BEFORE EJECTING ENEWD
ACROSS THE SOUTHERN APPALACHIANS/MID ATLANTIC STATES TONIGHT INTO
EARLY FRIDAY. INCREASING LOW LEVEL WARM ADVECTION INTERACTING WITH
LOW-MID LEVEL FGEN WILL SUPPORT A ZONE OF ISENTROPIC LIFT-
GENERATED SNOW SPREADING WEST-TO-EAST ACROSS MUCH OF CENTRAL PA
FROM LATE THIS EVENING/EARLY TONIGHT INTO FRIDAY MORNING. AT THIS
POINT THE THURSDAY EVENING COMMUTE DOES NOT APPEAR TO BE IMPACTED
BY THE INCOMING LIGHT SNOW. THE BROAD AREA OF LIFT IS LOCATED
WELL TO THE NORTH OF A DEVELOPING SFC LOW NEAR THE NC OBX BY
04/12Z.
MAIN FCST ISSUE IS TOTAL SNOW FCST AMTS AND POTENTIAL NEED FOR A
WINTER WX ADVISORY ACROSS THE LOWER SUSQ VALLEY. WE STRONGLY
CONSIDERED ISSUING AN ADVISORY FOR THE LOWER SUSQ COUNTIES BASED
ON NEW 2 INCH CRITERIA AND IMPACTS RELATED TO THE FRIDAY MORNING
COMMUTE. CONSENSUS BLEND OF GLOBAL/REGIONAL MODEL QPF FAVORED 1.5-3
INCHES OF SNOW OVER MUCH OF THE AREA...BUT THE HI RES ENSEMBLE
SSEO/NCAR OUTPUT CAME IN LOWER AT 1-2 INCHES WITH SUB-1 INCH AMTS
IN THE LOWEST ELEVATIONS. WE DECIDED TO HOLD OFF ON THE ADVY FOR
NOW AND ALLOW DAYSHIFT TO EXAMINE THE HRRR AND NEWER MDL
DATA...STILL WITH SUFFICIENT LEAD TIME/HEADS UP FOR LIGHT SNOW
ACCUMULATION IMPACTS (FRIDAY AM COMMUTE). WE COULD SEE A BOOM
SCENARIO WHERE SOME PERSISTENT FGEN BANDING AND HIGHER SLR/S
AFFORD SOME LOCAL 3+ INCH AMOUNTS...WHILE ON THE OTHER HAND COULD
SEE LOWER AMOUNTS VERIFYING GIVEN LIMITED FORCING AND BEST
MOISTURE TO THE SOUTH.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
LGT SNOW SHOULD TAPER OFF BY LATE AM ACROSS THE AREA...AS MID LVL
TROF AXIS SWINGS EAST OF THE AREA. DEEP MOISTURE ASSOC WITH
DEVELOPING COASTAL LOW NR CAPE HATTERAS IS PROGGED BY ALL MDL DATA
TO REMAIN SOUTH OF PA...SO SNOW ACCUMS SHOULD REMAIN LIGHT.
SOME BRIGHTENING EXPECTED BY AFTN PER MDL SOUNDINGS...AS COASTAL
LOW EXITS THE E COAST. HOWEVER...DIURNAL HEATING COMBINED W/COOL
TEMPS ALOFT SHOULD RESULT IN QUITE A BIT OF LINGERING STRATOCU.
BLEND OF LATEST SUPERBLEND AND ECME MOS SUPPORT HIGH TEMPS SEVERAL
DEG BLW AVG...MAINLY 35-40F.
CLEARING SKIES AND LIGHT WIND UPON ARRIVAL OF SFC RIDGE SHOULD
ALLOW TEMPS TO FALL QUICKLY FRI EVENING. HOWEVER...COMPLICATING
FACTOR W/REGARD TO MIN TEMPS WILL BE THE POTENTIAL ARRIVAL OF
CLOUDS BEFORE DAWN ASSOC WITH APPROACHING CLIPPER. ENSEMBLE TEMP
PLUMES SHOWING A FAIR AMT OF SPREAD IN THE MIN
TEMPS...ILLUSTRATING THE UNCERTAINTY. WILL TAKE THE MIDDLE ROAD
FOR NOW WITH A FCST OF UTEENS NORTH TO M20S SE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A FAIR AMT OF AGREEMENT AMONG MED RANGE MDLS W/REGARD TO
STRENGTH/TIMING OF WEEKEND CLIPPER...ALL OF WHICH POINT TOWARD A
RELATIVELY WEAK AND DEFINITELY MOISTURE-STARVED SYSTEM. LATEST
GEFS/SREF MEAN QPF SUPPORTS A 1-2 INCH SNOWFALL WITH THE W MTNS
CLIMATOLOGICALLY FAVORED FOR THE HIGHEST AMTS. ALTHOUGH MDL TIMING
OF SFC LOW SUGGEST THE STEADIEST SNOW SHOULD FALL SAT NIGHT...SOME
VERY LGT SNOW IS ALSO POSSIBLE DURING THE DAYTIME SAT IN WAA
AHEAD OF LEAD SHORTWAVE. ABV FREEZING SFC TEMPS AND MARCH SUN
ANGLE SHOULD PRECLUDE DAYTIME ACCUMS.
BRIGHTENING SKIES BUT STILL CHILLY WX ANTICIPATED SUNDAY...AS HIGH
PRES BUILDS IN FROM THE WEST. WIDE CONSENSUS AMONG MED RANGE
GUIDANCE IN A MARKED WARM UP NEXT WEEK...AS ANOMALOUS UPPER LVL
RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND ASSOC SW FLOW OVR
PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER 00Z ECENS. HAVE
CONSERVATIVELY BUMPED TEMPS UPWARD TO ARND 70F BY WED OVR
SOUTHERN PA.
A QUASI-STATIONARY FRONTAL BOUNDARY RUNNING FROM THE
MISS VALLEY THRU THE GRT LKS AT INTERFACE OF E COAST RIDGE AND
PLAINS TROF COULD POTENTIALLY COME CLOSE ENOUGH TO NW PA TO BRING
SHOWERS BY MIDWEEK. HOWEVER...LATEST ECENS INDICATES THE MORE
LIKELY SCENARIO KEEPS FRONT AND CHC OF RAIN NW OF PENNSYLVANIA.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
FOR THE 03/12Z TAFS THROUGH 04/12Z FRIDAY
ISSUED AT 705 AM EST MAR 03 2016
LINGERING MVFR CIG AT JST WILL IMPROVE TO VFR BY 14Z. INCREASING
AND THICKENING VFR MID CLOUDS WILL SPREAD FROM WEST-TO-EAST ACROSS
THE AIRSPACE BY THIS AFTERNOON BEFORE CIGS TREND LOWER THIS
EVENING. WIDESPREAD -SN AND IFR VIS WILL IMPACT ALL TERMINALS
TONIGHT INTO EARLY FRIDAY MORNING.
OUTLOOK...
FRI...AM -SN WITH MVFR CIGS. IMPROVING CONDS BY FRI EVE/NGT.
SAT...VFR/MVFR CIGS EARLY THEN CHC OF -SN SAT NGT.
SUN...MVFR CIGS WEST BCMG VFR.
MON...VFR/NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD/STEINBUGL
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
630 AM EST THU MAR 3 2016
.SYNOPSIS...
LINGERING SNOW SHOWERS AND FLURRIES WILL GIVE WAY TO FAIR WEATHER
LATER TODAY. A WIDESPREAD LIGHT SNOW ACCUMULATION OF 1 TO 2
INCHES IS EXPECTED TONIGHT INTO FRIDAY MORNING. ADDITIONAL LIGHT
SNOW IS POSSIBLE SATURDAY EVENING INTO EARLY SUNDAY. THE FORECAST
FOR NEXT WEEK LOOKS MILD WITH HIGH CONFIDENCE IN ABOVE NORMAL
TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
IR SATELLITE AND RADAR TRENDS SHOW DECREASING COVERAGE OF LAKE
STRATOCU AND SNOW SHOWERS/FLURRIES. MOST AREAS SHOULD SEE SOME
SUNSHINE THIS MORNING BEFORE CLOUDS INCREASE FROM THE WEST AND
THICKEN THROUGH THE AFTERNOON.
SHORTWAVE DIGGING SOUTHEAST INTO THE MID MS VALLEY THIS MORNING
WILL MOVE THROUGH THE TN VALLEY TODAY BEFORE EJECTING ENEWD
ACROSS THE SOUTHERN APPALACHIANS/MID ATLANTIC STATES TONIGHT INTO
EARLY FRIDAY. INCREASING LOW LEVEL WARM ADVECTION INTERACTING WITH
LOW-MID LEVEL FGEN WILL SUPPORT A ZONE OF ISENTROPIC LIFT-
GENERATED SNOW SPREADING WEST-TO-EAST ACROSS MUCH OF CENTRAL PA
FROM LATE THIS EVENING/EARLY TONIGHT INTO FRIDAY MORNING. AT THIS
POINT THE THURSDAY EVENING COMMUTE DOES NOT APPEAR TO BE IMPACTED
BY THE INCOMING LIGHT SNOW. THE BROAD AREA OF LIFT IS LOCATED
WELL TO THE NORTH OF A DEVELOPING SFC LOW NEAR THE NC OBX BY
04/12Z.
MAIN FCST ISSUE IS TOTAL SNOW FCST AMTS AND POTENTIAL NEED FOR A
WINTER WX ADVISORY ACROSS THE LOWER SUSQ VALLEY. WE STRONGLY
CONSIDERED ISSUING AN ADVISORY FOR THE LOWER SUSQ COUNTIES BASED
ON NEW 2 INCH CRITERIA AND IMPACTS RELATED TO THE FRIDAY MORNING
COMMUTE. CONSENSUS BLEND OF GLOBAL/REGIONAL MODEL QPF FAVORED 1.5-3
INCHES OF SNOW OVER MUCH OF THE AREA...BUT THE HI RES ENSEMBLE
SSEO/NCAR OUTPUT CAME IN LOWER AT 1-2 INCHES WITH SUB-1 INCH AMTS
IN THE LOWEST ELEVATIONS. WE DECIDED TO HOLD OFF ON THE ADVY FOR
NOW AND ALLOW DAYSHIFT TO EXAMINE THE HRRR AND NEWER MDL
DATA...STILL WITH SUFFICIENT LEAD TIME/HEADS UP FOR LIGHT SNOW
ACCUMULATION IMPACTS (FRIDAY AM COMMUTE). WE COULD SEE A BOOM
SCENARIO WHERE SOME PERSISTENT FGEN BANDING AND HIGHER SLR/S
AFFORD SOME LOCAL 3+ INCH AMOUNTS...WHILE ON THE OTHER HAND COULD
SEE LOWER AMOUNTS VERIFYING GIVEN LIMITED FORCING AND BEST
MOISTURE TO THE SOUTH.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
LGT SNOW SHOULD TAPER OFF BY LATE AM ACROSS THE AREA...AS MID LVL
TROF AXIS SWINGS EAST OF THE AREA. DEEP MOISTURE ASSOC WITH
DEVELOPING COASTAL LOW NR CAPE HATTERAS IS PROGGED BY ALL MDL DATA
TO REMAIN SOUTH OF PA...SO SNOW ACCUMS SHOULD REMAIN LIGHT.
SOME BRIGHTENING EXPECTED BY AFTN PER MDL SOUNDINGS...AS COASTAL
LOW EXITS THE E COAST. HOWEVER...DIURNAL HEATING COMBINED W/COOL
TEMPS ALOFT SHOULD RESULT IN QUITE A BIT OF LINGERING STRATOCU.
BLEND OF LATEST SUPERBLEND AND ECME MOS SUPPORT HIGH TEMPS SEVERAL
DEG BLW AVG...MAINLY 35-40F.
CLEARING SKIES AND LIGHT WIND UPON ARRIVAL OF SFC RIDGE SHOULD
ALLOW TEMPS TO FALL QUICKLY FRI EVENING. HOWEVER...COMPLICATING
FACTOR W/REGARD TO MIN TEMPS WILL BE THE POTENTIAL ARRIVAL OF
CLOUDS BEFORE DAWN ASSOC WITH APPROACHING CLIPPER. ENSEMBLE TEMP
PLUMES SHOWING A FAIR AMT OF SPREAD IN THE MIN
TEMPS...ILLUSTRATING THE UNCERTAINTY. WILL TAKE THE MIDDLE ROAD
FOR NOW WITH A FCST OF UTEENS NORTH TO M20S SE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A FAIR AMT OF AGREEMENT AMONG MED RANGE MDLS W/REGARD TO
STRENGTH/TIMING OF WEEKEND CLIPPER...ALL OF WHICH POINT TOWARD A
RELATIVELY WEAK AND DEFINITELY MOISTURE-STARVED SYSTEM. LATEST
GEFS/SREF MEAN QPF SUPPORTS A 1-2 INCH SNOWFALL WITH THE W MTNS
CLIMATOLOGICALLY FAVORED FOR THE HIGHEST AMTS. ALTHOUGH MDL TIMING
OF SFC LOW SUGGEST THE STEADIEST SNOW SHOULD FALL SAT NIGHT...SOME
VERY LGT SNOW IS ALSO POSSIBLE DURING THE DAYTIME SAT IN WAA
AHEAD OF LEAD SHORTWAVE. ABV FREEZING SFC TEMPS AND MARCH SUN
ANGLE SHOULD PRECLUDE DAYTIME ACCUMS.
BRIGHTENING SKIES BUT STILL CHILLY WX ANTICIPATED SUNDAY...AS HIGH
PRES BUILDS IN FROM THE WEST. WIDE CONSENSUS AMONG MED RANGE
GUIDANCE IN A MARKED WARM UP NEXT WEEK...AS ANOMALOUS UPPER LVL
RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND ASSOC SW FLOW OVR
PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER 00Z ECENS. HAVE
CONSERVATIVELY BUMPED TEMPS UPWARD TO ARND 70F BY WED OVR
SOUTHERN PA.
A QUASI-STATIONARY FRONTAL BOUNDARY RUNNING FROM THE
MISS VALLEY THRU THE GRT LKS AT INTERFACE OF E COAST RIDGE AND
PLAINS TROF COULD POTENTIALLY COME CLOSE ENOUGH TO NW PA TO BRING
SHOWERS BY MIDWEEK. HOWEVER...LATEST ECENS INDICATES THE MORE
LIKELY SCENARIO KEEPS FRONT AND CHC OF RAIN NW OF PENNSYLVANIA.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
FOR THE 03/06Z TAFS THROUGH 04/06Z
ISSUED AT 127 AM EST MAR 03 2016
LINGERING -SHSN AND MVFR TO LOW VFR CIGS /2-5KFT AGL/ WILL
CONTINUE ACROSS THE NW 1/2 OF THE AIRSPACE EARLY THIS MORNING.
EXPECT -SHSN TO DIMINISH BY LATE MORNING WITH MOST SITES VFR.
THICKENING VFR MID CLOUDS WILL SPREAD ACROSS THE AIRSPACE THIS
AFTERNOON BEFORE CIGS TREND LOWER THIS EVENING. WIDESPREAD -SN IS
FCST TO DEVELOP INTO TONIGHT AND HAVE ADDED IFR GROUP 00-04Z WHICH
SHOULD PERSIST INTO EARLY FRIDAY MORNING.
OUTLOOK...
FRI...-SN WITH MVFR CIGS. IMPROVING CONDS BY FRI EVE/NGT.
SAT...VFR/MVFR CIGS EARLY THEN CHC OF -SN SAT NGT.
SUN...MVFR CIGS WEST BCMG VFR.
MON...VFR/NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD/STEINBUGL
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
555 AM EST THU MAR 3 2016
.SYNOPSIS...
LINGERING SNOW SHOWERS AND FLURRIES WILL GIVE WAY TO FAIR WEATHER
LATER TODAY. A WIDESPREAD LIGHT SNOW ACCUMULATION OF 1 TO 2
INCHES IS EXPECTED TONIGHT INTO FRIDAY MORNING. ADDITIONAL LIGHT
SNOW IS POSSIBLE SATURDAY EVENING INTO EARLY SUNDAY. THE FORECAST
FOR NEXT WEEK LOOKS MILD WITH HIGH CONFIDENCE IN ABOVE NORMAL
TEMPERATURES.
&&
.NEAR TERM /THROUGH TONIGHT/...
IR SATELLITE AND RADAR TRENDS SHOW DECREASING COVERAGE OF LAKE
STRATOCU AND SNOW SHOWERS/FLURRIES. MOST AREAS SHOULD SEE SOME
SUNSHINE THIS MORNING BEFORE CLOUDS INCREASE FROM THE WEST AND
THICKEN THROUGH THE AFTERNOON.
SHORTWAVE DIGGING SOUTHEAST INTO THE MID MS VALLEY THIS MORNING
WILL MOVE THROUGH THE TN VALLEY TODAY BEFORE EJECTING ENEWD
ACROSS THE SOUTHERN APPALACHIANS/MID ATLANTIC STATES TONIGHT INTO
EARLY FRIDAY. INCREASING LOW LEVEL WARM ADVECTION INTERACTING WITH
LOW-MID LEVEL FGEN WILL SUPPORT A ZONE OF ISENTROPIC LIFT-
GENERATED SNOW SPREADING WEST-TO-EAST ACROSS MUCH OF CENTRAL PA
FROM LATE THIS EVENING/EARLY TONIGHT INTO FRIDAY MORNING. AT THIS
POINT THE THURSDAY EVENING COMMUTE DOES NOT APPEAR TO BE IMPACTED
BY THE INCOMING LIGHT SNOW. THE BROAD AREA OF LIFT IS LOCATED
WELL TO THE NORTH OF A DEVELOPING SFC LOW NEAR THE NC OBX BY
04/12Z.
MAIN FCST ISSUE IS TOTAL SNOW FCST AMTS AND POTENTIAL NEED FOR A
WINTER WX ADVISORY ACROSS THE LOWER SUSQ VALLEY. WE STRONGLY
CONSIDERED ISSUING AN ADVISORY FOR THE LOWER SUSQ COUNTIES BASED
ON NEW 2 INCH CRITERIA AND IMPACTS RELATED TO THE FRIDAY MORNING
COMMUTE. CONSENSUS BLEND OF GLOBAL/REGIONAL MODEL QPF FAVORED 1.5-3
INCHES OF SNOW OVER MUCH OF THE AREA...BUT THE HI RES ENSEMBLE
SSEO/NCAR OUTPUT CAME IN LOWER AT 1-2 INCHES WITH SUB-1 INCH AMTS
IN THE LOWEST ELEVATIONS. WE DECIDED TO HOLD OFF ON THE ADVY FOR
NOW AND ALLOW DAYSHIFT TO EXAMINE THE HRRR AND NEWER MDL
DATA...STILL WITH SUFFICIENT LEAD TIME/HEADS UP FOR LIGHT SNOW
ACCUMULATION IMPACTS (FRIDAY AM COMMUTE). WE COULD SEE A BOOM
SCENARIO WHERE SOME PERSISTENT FGEN BANDING AND HIGHER SLR/S
AFFORD SOME LOCAL 3+ INCH AMOUNTS...WHILE ON THE OTHER HAND COULD
SEE LOWER AMOUNTS VERIFYING GIVEN LIMITED FORCING AND BEST
MOISTURE TO THE SOUTH.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
LGT SNOW SHOULD TAPER OFF BY LATE AM ACROSS THE AREA...AS MID LVL
TROF AXIS SWINGS EAST OF THE AREA. DEEP MOISTURE ASSOC WITH
DEVELOPING COASTAL LOW NR CAPE HATTERAS IS PROGGED BY ALL MDL DATA
TO REMAIN SOUTH OF PA...SO SNOW ACCUMS SHOULD REMAIN LIGHT.
SOME BRIGHTENING EXPECTED BY AFTN PER MDL SOUNDINGS...AS COASTAL
LOW EXITS THE E COAST. HOWEVER...DIURNAL HEATING COMBINED W/COOL
TEMPS ALOFT SHOULD RESULT IN QUITE A BIT OF LINGERING STRATOCU.
BLEND OF LATEST SUPERBLEND AND ECME MOS SUPPORT HIGH TEMPS SEVERAL
DEG BLW AVG...MAINLY 35-40F.
CLEARING SKIES AND LIGHT WIND UPON ARRIVAL OF SFC RIDGE SHOULD
ALLOW TEMPS TO FALL QUICKLY FRI EVENING. HOWEVER...COMPLICATING
FACTOR W/REGARD TO MIN TEMPS WILL BE THE POTENTIAL ARRIVAL OF
CLOUDS BEFORE DAWN ASSOC WITH APPROACHING CLIPPER. ENSEMBLE TEMP
PLUMES SHOWING A FAIR AMT OF SPREAD IN THE MIN
TEMPS...ILLUSTRATING THE UNCERTAINTY. WILL TAKE THE MIDDLE ROAD
FOR NOW WITH A FCST OF UTEENS NORTH TO M20S SE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A FAIR AMT OF AGREEMENT AMONG MED RANGE MDLS W/REGARD TO
STRENGTH/TIMING OF WEEKEND CLIPPER...ALL OF WHICH POINT TOWARD A
RELATIVELY WEAK AND DEFINITELY MOISTURE-STARVED SYSTEM. LATEST
GEFS/SREF MEAN QPF SUPPORTS A 1-2 INCH SNOWFALL WITH THE W MTNS
CLIMATOLOGICALLY FAVORED FOR THE HIGHEST AMTS. ALTHOUGH MDL TIMING
OF SFC LOW SUGGEST THE STEADIEST SNOW SHOULD FALL SAT NIGHT...SOME
VERY LGT SNOW IS ALSO POSSIBLE DURING THE DAYTIME SAT IN WAA
AHEAD OF LEAD SHORTWAVE. ABV FREEZING SFC TEMPS AND MARCH SUN
ANGLE SHOULD PRECLUDE DAYTIME ACCUMS.
BRIGHTENING SKIES BUT STILL CHILLY WX ANTICIPATED SUNDAY...AS HIGH
PRES BUILDS IN FROM THE WEST. WIDE CONSENSUS AMONG MED RANGE
GUIDANCE IN A MARKED WARM UP NEXT WEEK...AS ANOMALOUS UPPER LVL
RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND ASSOC SW FLOW OVR
PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER 00Z ECENS. HAVE
CONSERVATIVELY BUMPED TEMPS UPWARD TO ARND 70F BY WED OVR
SOUTHERN PA.
A QUASI-STATIONARY FRONTAL BOUNDARY RUNNING FROM THE
MISS VALLEY THRU THE GRT LKS AT INTERFACE OF E COAST RIDGE AND
PLAINS TROF COULD POTENTIALLY COME CLOSE ENOUGH TO NW PA TO BRING
SHOWERS BY MIDWEEK. HOWEVER...LATEST ECENS INDICATES THE MORE
LIKELY SCENARIO KEEPS FRONT AND CHC OF RAIN NW OF PENNSYLVANIA.
&&
.AVIATION /10Z THURSDAY THROUGH MONDAY/...
FOR THE 03/06Z TAFS THROUGH 04/06Z
ISSUED AT 127 AM EST MAR 03 2016
LINGERING -SHSN AND MVFR TO LOW VFR CIGS /2-5KFT AGL/ WILL
CONTINUE ACROSS THE NW 1/2 OF THE AIRSPACE EARLY THIS MORNING.
EXPECT -SHSN TO DIMINISH BY LATE MORNING WITH MOST SITES VFR.
THICKENING VFR MID CLOUDS WILL SPREAD ACROSS THE AIRSPACE THIS
AFTERNOON BEFORE CIGS TREND LOWER THIS EVENING. WIDESPREAD -SN IS
FCST TO DEVELOP INTO TONIGHT AND HAVE ADDED IFR GROUP 00-04Z WHICH
SHOULD PERSIST INTO EARLY FRIDAY MORNING.
OUTLOOK...
FRI...-SN WITH MVFR CIGS. IMPROVING CONDS BY FRI EVE/NGT.
SAT...VFR/MVFR CIGS EARLY THEN CHC OF -SN SAT NGT.
SUN...MVFR CIGS WEST BCMG VFR.
MON...VFR/NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
427 AM EST THU MAR 3 2016
.SYNOPSIS...
LINGERING SNOW SHOWERS AND FLURRIES WILL GIVE WAY TO FAIR WEATHER
LATER TODAY. A WIDESPREAD LIGHT SNOW ACCUMULATION OF 1 TO 2
INCHES IS EXPECTED TONIGHT INTO FRIDAY MORNING. ADDITIONAL LIGHT
SNOW IS POSSIBLE SATURDAY EVENING INTO EARLY SUNDAY. THE FORECAST
FOR NEXT WEEK LOOKS MILD WITH HIGH CONFIDENCE IN ABOVE NORMAL
TEMPERATURES.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
IR SATELLITE AND RADAR TRENDS SHOW DECREASING COVERAGE OF LAKE
STRATOCU AND SNOW SHOWERS/FLURRIES. MOST AREAS SHOULD SEE SOME
SUNSHINE THIS MORNING BEFORE CLOUDS INCREASE FROM THE WEST AND
THICKEN THROUGH THE AFTERNOON.
SHORTWAVE DIGGING SOUTHEAST INTO THE MID MS VALLEY THIS MORNING
WILL MOVE THROUGH THE TN VALLEY TODAY BEFORE EJECTING ENEWD
ACROSS THE SOUTHERN APPALACHIANS/MID ATLANTIC STATES TONIGHT INTO
EARLY FRIDAY. INCREASING LOW LEVEL WARM ADVECTION INTERACTING WITH
LOW-MID LEVEL FGEN WILL SUPPORT A ZONE OF ISENTROPIC LIFT-
GENERATED SNOW SPREADING WEST-TO-EAST ACROSS MUCH OF CENTRAL PA
FROM LATE THIS EVENING/EARLY TONIGHT INTO FRIDAY MORNING. AT THIS
POINT THE THURSDAY EVENING COMMUTE DOES NOT APPEAR TO BE IMPACTED
BY THE INCOMING LIGHT SNOW. THE BROAD AREA OF LIFT IS LOCATED
WELL TO THE NORTH OF A DEVELOPING SFC LOW NEAR THE NC OBX BY
04/12Z.
MAIN FCST ISSUE IS TOTAL SNOW FCST AMTS AND POTENTIAL NEED FOR A
WINTER WX ADVISORY ACROSS THE LOWER SUSQ VALLEY. WE STRONGLY
CONSIDERED ISSUING AN ADVISORY FOR THE LOWER SUSQ COUNTIES BASED
ON NEW 2 INCH CRITERIA AND IMPACTS RELATED TO THE FRIDAY MORNING
COMMUTE. CONSENSUS BLEND OF GLOBAL/REGIONAL MODEL QPF FAVORED 1.5-3
INCHES OF SNOW OVER MUCH OF THE AREA...BUT THE HI RES ENSEMBLE
SSEO/NCAR OUTPUT CAME IN LOWER AT 1-2 INCHES WITH SUB-1 INCH AMTS
IN THE LOWEST ELEVATIONS. WE DECIDED TO HOLD OFF ON THE ADVY FOR
NOW AND ALLOW DAYSHIFT TO EXAMINE THE HRRR AND NEWER MDL
DATA...STILL WITH SUFFICIENT LEAD TIME/HEADS UP FOR LIGHT SNOW
ACCUMULATION IMPACTS (FRIDAY AM COMMUTE). WE COULD SEE A BOOM
SCENARIO WHERE SOME PERSISTENT FGEN BANDING AND HIGHER SLR/S
AFFORD SOME LOCAL 3+ INCH AMOUNTS...WHILE ON THE OTHER HAND COULD
SEE LOWER AMOUNTS VERIFYING GIVEN LIMITED FORCING AND BEST
MOISTURE TO THE SOUTH.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH FRIDAY NIGHT/...
RIDGING SFC/ALOFT ARRIVING BEHIND DEPARTING STORM SYSTEM OFF THE
EAST COAST WILL END PCPN EARLY FRIDAY. EARLY CLOUDS SHOULD
DECREASE BY LATER IN THE DAY BEHIND A DRIER NORTHERLY FLOW...BUT
QUICKLY FILL BACK IN FRI NIGHT INTO SATURDAY MORNING AHEAD OF
CLIPPER LOW DIVING SOUTHEAST FROM MN TO NEAR CHICAGO IL BY
05/12Z.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
CLIPPER SHOULD BRING ANOTHER CHANCE FOR PRECIPITATION SATURDAY
NIGHT THROUGH THE FIRST HALF OF SUNDAY. THE EC AND GFS...ALONG
WITH THE ENSEMBLES ARE IN FAIR AGREEMENT ON THE POSITION AND
TIMING OF THE TROUGH....THOUGH THE GEFS BEGINS TO DIVERGE IN ANY
SOLUTION BY 12Z SUNDAY. SNOW REMAINS THE LIKELY PRECIP TYPE.
A LARGE RIDGE SHOULD BUILD IN QUICKLY BEHIND THIS SYSTEM...BRINGING
DRY WARM AIR TO THE REGION EARLY NEXT WEEK. THE TREND CONTINUES TO
SHOW HIGH PRESSURE THROUGH MID WEEK WHICH SHOULD SUPPORT ABOVE
NORMAL TEMPERATURES.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
FOR THE 03/06Z TAFS THROUGH 04/06Z
ISSUED AT 127 AM EST MAR 03 2016
LINGERING -SHSN AND MVFR TO LOW VFR CIGS /2-5KFT AGL/ WILL
CONTINUE ACROSS THE NW 1/2 OF THE AIRSPACE EARLY THIS MORNING.
EXPECT -SHSN TO DIMINISH BY LATE MORNING WITH MOST SITES VFR.
THICKENING VFR MID CLOUDS WILL SPREAD ACROSS THE AIRSPACE THIS
AFTERNOON BEFORE CIGS TREND LOWER THIS EVENING. WIDESPREAD -SN IS
FCST TO DEVELOP INTO TONIGHT AND HAVE ADDED IFR GROUP 00-04Z WHICH
SHOULD PERSIST INTO EARLY FRIDAY MORNING.
OUTLOOK...
FRI...-SN WITH MVFR CIGS. IMPROVING CONDS BY FRI EVE/NGT.
SAT...VFR/MVFR CIGS EARLY THEN CHC OF -SN SAT NGT.
SUN...MVFR CIGS WEST BCMG VFR.
MON...VFR/NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...DANGELO/RXR
LONG TERM...CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1144 AM CST THU MAR 3 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CST THU MAR 3 2016
DIFFICULT CLOUD FORECAST TODAY WITH A FAIR AMOUNT OF LOW LEVEL
SATURATION ACROSS THE AREA. CURRENTLY HAVE A FAIR AMOUNT OF MID
CLOUDS ACROSS SOUTHWEST MINNESOTA AND NORTHWEST
IOWA...HOWEVER...FURTHER TO THE WEST...MUCH LOWER CLOUDS ARE
DEVELOPING AS THE SURFACE FLOW BECOMES MORE NORTHERLY. MODEL
SOUNDING SUGGEST A STRATUS LAYER WILL TRY TO DEVELOP AT THE TOP OF
THE BOUNDARY LAYER TODAY. WITH RELATIVELY POOR MIXING CONDITIONS
AND SIGNIFICANT CLOUD COVER...HAVE LOWERED FORECAST HIGHS TODAY.
SHORT TERM HIGH RES MODELS INDICATE A FEW TRENDS ACROSS THE EASTERN
EDGE OF THE AREA THAT NEED WATCHING. FIRST...BOTH THE HRRR AND THE
RAP SUGGEST FOG DEVELOPING ACROSS NORTHWEST IOWA AND EXPANDING
WESTWARD TOWARDS THE I-29 CORRIDOR. WITH FOG STARTING TO DEVELOP AT
STORM LAKE CONFIDENCE IS GROWING WITH FOG AND WILL HAVE SOME PATCHY
AND AREAS MENTIONED. OTHER CONCERN IS WITH A WEAK SHORTWAVE MOVING
OUT OF NORTH DAKOTA INTO SOUTHWEST MINNESOTA. AS THIS WAVE PASSES
THROUGH IN THE 12-15Z TIME FRAME...MODEL SOUNDINGS SUGGEST THAT
SATURATION MAY GET DEEP ENOUGH TO TEMPORARILY SATURATE THE DENDRITIC
LAYER LEADING TO THE DEVELOPMENT OF SOME VERY LIGHT PRECIPITATION.
AT THIS POINT...OBSERVATIONS ARE DRY UPSTREAM...BUT WILL HAVE TO KEEP
A CLOSE EYE ON WORTHING TO SPIRIT LAKE AREA THIS MORNING.
FAIR AMOUNT OF CLOUDS ARE EXPECTED TO STICK AROUND THE AREA AGAIN
TONIGHT. AS SOUTHEASTERLY WINDS INCREASE FROM WEST TO EAST...EXPECT
TEMPERATURES TO STEADY OUT...IF NOT RISE A DEGREE OR TWO. HAVE A
SLIGHT NON-DIURNAL CURVE...ESPECIALLY ACROSS CENTRAL SOUTH DAKOTA.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 331 AM CST THU MAR 3 2016
AN EXTENDED WARMUP IS IN STORE FOR THE REGION AS WE MOVE INTO THE
MEDIUM AND THROUGH THE EXTENDED PORTIONS OF THE FORECAST. A MODEST
UPPER WAVE WILL TRACK THROUGH THE NORTHERN PLAINS FRIDAY.
GENERALLY...MOISTURE WILL BE LIMITED WITH THIS WAVE...AND SHOULD
KEEP ANY PRECIPITATION THROUGH THE FIRST HALF OF FRIDAY ON THE
LIGHT SIDE. RAIN MAY BE THE PREDOMINATE PRECIPITATION FORM...BUT
WOULD NOT RULE OUT A FEW SNOWFLAKES MIXING IN ESPECIALLY ALONG THE
BUFFALO RIDGE AREA OF SW MINNESOTA.
SURFACE HIGH PRESSURE WILL SLIDE ACROSS THE AREA BY SATURDAY
MORNING...SIGNALING A RETURN OF WARMER SOUTHERLY FLOW FOR THE
REMAINDER OF THE WEEKEND AND INTO NEXT WEEK. TEMPERATURES WILL BEGIN
TO WARM ON SATURDAY...BUT LINGERING SNOW MAY KEEP READINGS DOWN A
COUPLE DEGREES FROM THEIR POTENTIAL LEVELS. BY SUNDAY...GUSTY
SOUTHWESTERLY WINDS SHOULD PUSH READINGS THROUGH THE 50S...WITH 60S
POSSIBLE IN MANY AREAS. STRATUS REMAINS A CONCERN FOR SUNDAY...AND
IT MAY HAMPER HIGHS JUST A BIT IF IT DEVELOPS AS ADVERTISED BY THE
GFS.
AN UPPER TROUGH LIFTING OUT OF THE FOUR CORNERS REGION OF THE US
WILL AMPLIFY SOUTHWESTERLY FLOW IN THE LOWER LEVELS...BRINGING AN
INCREASING RISK FOR LIGHT SHOWERS OR DRIZZLE BY MONDAY MORNING.
INSTABILITY WILL BEGIN TO INCREASE AHEAD OF THIS UPPER TROUGH LATER
ON MONDAY...AND WILL BRING AND INCREASING RISK FOR THUNDERSTORMS TO
THE CWA BY MONDAY AFTERNOON AND EVENING. HIGHEST INSTABILITY LVLS
REMAIN NEAR THE MO RIVER VALLEY...AND CAPPING LAYER REMAINS IN
PLACE AS THE FRONT SLIDES INTO THE AREA...BUT GIVEN AMPLITUDE OF
SHEAR...COULD NOT RULE OUT A STRONGER STORM OR TWO INTO MONDAY
NIGHT.
LOW-LVL TROUGH PASSAGE WILL OCCUR MONDAY NIGHT INTO TUESDAY
MORNING...BUT SHOULD IT SLOW DOWN...A LINGERING RISK FOR A FEW
THUNDERSTORMS WILL CONTINUE OVER NW IA AND SW MN TUESDAY MORNING.
OTHERWISE...DEFORMATION PRECIPITATION AREA ON THE BACKSIDE OF THE
ADVANCING TROUGH SHOULD BRING SHOWERS TO THE CWA ON TUESDAY.
IF YOU ARE A FAN OF SPRING...THE OUTLOOK THROUGH NEXT WEEK REMAINS
WARM. ABOVE NORMAL TEMPERATURES LOOK LIKELY THROUGH NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1144 AM CST THU MAR 3 2016
CEILINGS 1-3K FEET...EXCEPT THRU 04/00Z CEILINGS 3-5K FEET EAST
AND NORTH OF A HON/FSD/SPW LINE. AFTER 04/00Z CEILINGS BECOMING
1-3K FEET ACROSS THE AREA. AREAS OF CEILINGS BELOW 1K FEET
04/06Z-16Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...DUX
AVIATION...
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
538 AM CST THU MAR 3 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CST THU MAR 3 2016
DIFFICULT CLOUD FORECAST TODAY WITH A FAIR AMOUNT OF LOW LEVEL
SATURATION ACROSS THE AREA. CURRENTLY HAVE A FAIR AMOUNT OF MID
CLOUDS ACROSS SOUTHWEST MINNESOTA AND NORTHWEST
IOWA...HOWEVER...FURTHER TO THE WEST...MUCH LOWER CLOUDS ARE
DEVELOPING AS THE SURFACE FLOW BECOMES MORE NORTHERLY. MODEL
SOUNDING SUGGEST A STRATUS LAYER WILL TRY TO DEVELOP AT THE TOP OF
THE BOUNDARY LAYER TODAY. WITH RELATIVELY POOR MIXING CONDITIONS
AND SIGNIFICANT CLOUD COVER...HAVE LOWERED FORECAST HIGHS TODAY.
SHORT TERM HIGH RES MODELS INDICATE A FEW TRENDS ACROSS THE EASTERN
EDGE OF THE AREA THAT NEED WATCHING. FIRST...BOTH THE HRRR AND THE
RAP SUGGEST FOG DEVELOPING ACROSS NORTHWEST IOWA AND EXPANDING
WESTWARD TOWARDS THE I-29 CORRIDOR. WITH FOG STARTING TO DEVELOP AT
STORM LAKE CONFIDENCE IS GROWING WITH FOG AND WILL HAVE SOME PATCHY
AND AREAS MENTIONED. OTHER CONCERN IS WITH A WEAK SHORTWAVE MOVING
OUT OF NORTH DAKOTA INTO SOUTHWEST MINNESOTA. AS THIS WAVE PASSES
THROUGH IN THE 12-15Z TIME FRAME...MODEL SOUNDINGS SUGGEST THAT
SATURATION MAY GET DEEP ENOUGH TO TEMPORARILY SATURATE THE DENDRITIC
LAYER LEADING TO THE DEVELOPMENT OF SOME VERY LIGHT PRECIPITATION.
AT THIS POINT...OBSERVATIONS ARE DRY UPSTREAM...BUT WILL HAVE TO KEEP
A CLOSE EYE ON WORTHING TO SPIRIT LAKE AREA THIS MORNING.
FAIR AMOUNT OF CLOUDS ARE EXPECTED TO STICK AROUND THE AREA AGAIN
TONIGHT. AS SOUTHEASTERLY WINDS INCREASE FROM WEST TO EAST...EXPECT
TEMPERATURES TO STEADY OUT...IF NOT RISE A DEGREE OR TWO. HAVE A
SLIGHT NON-DIURNAL CURVE...ESPECIALLY ACROSS CENTRAL SOUTH DAKOTA.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 331 AM CST THU MAR 3 2016
AN EXTENDED WARMUP IS IN STORE FOR THE REGION AS WE MOVE INTO THE
MEDIUM AND THROUGH THE EXTENDED PORTIONS OF THE FORECAST. A MODEST
UPPER WAVE WILL TRACK THROUGH THE NORTHERN PLAINS FRIDAY.
GENERALLY...MOISTURE WILL BE LIMITED WITH THIS WAVE...AND SHOULD
KEEP ANY PRECIPITATION THROUGH THE FIRST HALF OF FRIDAY ON THE
LIGHT SIDE. RAIN MAY BE THE PREDOMINATE PRECIPITATION FORM...BUT
WOULD NOT RULE OUT A FEW SNOWFLAKES MIXING IN ESPECIALLY ALONG THE
BUFFALO RIDGE AREA OF SW MINNESOTA.
SURFACE HIGH PRESSURE WILL SLIDE ACROSS THE AREA BY SATURDAY
MORNING...SIGNALING A RETURN OF WARMER SOUTHERLY FLOW FOR THE
REMAINDER OF THE WEEKEND AND INTO NEXT WEEK. TEMPERATURES WILL BEGIN
TO WARM ON SATURDAY...BUT LINGERING SNOW MAY KEEP READINGS DOWN A
COUPLE DEGREES FROM THEIR POTENTIAL LEVELS. BY SUNDAY...GUSTY
SOUTHWESTERLY WINDS SHOULD PUSH READINGS THROUGH THE 50S...WITH 60S
POSSIBLE IN MANY AREAS. STRATUS REMAINS A CONCERN FOR SUNDAY...AND
IT MAY HAMPER HIGHS JUST A BIT IF IT DEVELOPS AS ADVERTISED BY THE
GFS.
AN UPPER TROUGH LIFTING OUT OF THE FOUR CORNERS REGION OF THE US
WILL AMPLIFY SOUTHWESTERLY FLOW IN THE LOWER LEVELS...BRINGING AN
INCREASING RISK FOR LIGHT SHOWERS OR DRIZZLE BY MONDAY MORNING.
INSTABILITY WILL BEGIN TO INCREASE AHEAD OF THIS UPPER TROUGH LATER
ON MONDAY...AND WILL BRING AND INCREASING RISK FOR THUNDERSTORMS TO
THE CWA BY MONDAY AFTERNOON AND EVENING. HIGHEST INSTABILITY LVLS
REMAIN NEAR THE MO RIVER VALLEY...AND CAPPING LAYER REMAINS IN
PLACE AS THE FRONT SLIDES INTO THE AREA...BUT GIVEN AMPLITUDE OF
SHEAR...COULD NOT RULE OUT A STRONGER STORM OR TWO INTO MONDAY
NIGHT.
LOW-LVL TROUGH PASSAGE WILL OCCUR MONDAY NIGHT INTO TUESDAY
MORNING...BUT SHOULD IT SLOW DOWN...A LINGERING RISK FOR A FEW
THUNDERSTORMS WILL CONTINUE OVER NW IA AND SW MN TUESDAY MORNING.
OTHERWISE...DEFORMATION PRECIPITATION AREA ON THE BACKSIDE OF THE
ADVANCING TROUGH SHOULD BRING SHOWERS TO THE CWA ON TUESDAY.
IF YOU ARE A FAN OF SPRING...THE OUTLOOK THROUGH NEXT WEEK REMAINS
WARM. ABOVE NORMAL TEMPERATURES LOOK LIKELY THROUGH NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 535 AM CST THU MAR 3 2016
AS THE FLOW BECOMES MORE NORTHERLY...LOWER CEILINGS ARE BUILDING
INTO THE AREA AND HAVE WROTE A FAIRLY PESSIMISTIC SET OF TAFS.
MODEL SOUNDINGS ALSO SUGGEST STRATUS DEVELOPING AND LINGERING
THROUGHOUT THE DAY. AS WINDS GO LIGHT TONIGHT...EXPECT STRATUS TO
REMAIN ACROSS THE AREA...POTENTIALLY LEADING TO CONDITIONS LOWER
THAN IFR.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...DUX
AVIATION...
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
334 AM CST THU MAR 3 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CST THU MAR 3 2016
DIFFICULT CLOUD FORECAST TODAY WITH A FAIR AMOUNT OF LOW LEVEL
SATURATION ACROSS THE AREA. CURRENTLY HAVE A FAIR AMOUNT OF MID
CLOUDS ACROSS SOUTHWEST MINNESOTA AND NORTHWEST
IOWA...HOWEVER...FURTHER TO THE WEST...MUCH LOWER CLOUDS ARE
DEVELOPING AS THE SURFACE FLOW BECOMES MORE NORTHERLY. MODEL
SOUNDING SUGGEST A STRATUS LAYER WILL TRY TO DEVELOP AT THE TOP OF
THE BOUNDARY LAYER TODAY. WITH RELATIVELY POOR MIXING CONDITIONS
AND SIGNIFICANT CLOUD COVER...HAVE LOWERED FORECAST HIGHS TODAY.
SHORT TERM HIGH RES MODELS INDICATE A FEW TRENDS ACROSS THE EASTERN
EDGE OF THE AREA THAT NEED WATCHING. FIRST...BOTH THE HRRR AND THE
RAP SUGGEST FOG DEVELOPING ACROSS NORTHWEST IOWA AND EXPANDING
WESTWARD TOWARDS THE I-29 CORRIDOR. WITH FOG STARTING TO DEVELOP AT
STORM LAKE CONFIDENCE IS GROWING WITH FOG AND WILL HAVE SOME PATCHY
AND AREAS MENTIONED. OTHER CONCERN IS WITH A WEAK SHORTWAVE MOVING
OUT OF NORTH DAKOTA INTO SOUTHWEST MINNESOTA. AS THIS WAVE PASSES
THROUGH IN THE 12-15Z TIME FRAME...MODEL SOUNDINGS SUGGEST THAT
SATURATION MAY GET DEEP ENOUGH TO TEMPORARILY SATURATE THE DENDRITIC
LAYER LEADING TO THE DEVELOPMENT OF SOME VERY LIGHT PRECIPITATION.
AT THIS POINT...OBSERVATIONS ARE DRY UPSTREAM...BUT WILL HAVE TO KEEP
A CLOSE EYE ON WORTHING TO SPIRIT LAKE AREA THIS MORNING.
FAIR AMOUNT OF CLOUDS ARE EXPECTED TO STICK AROUND THE AREA AGAIN
TONIGHT. AS SOUTHEASTERLY WINDS INCREASE FROM WEST TO EAST...EXPECT
TEMPERATURES TO STEADY OUT...IF NOT RISE A DEGREE OR TWO. HAVE A
SLIGHT NON-DIURNAL CURVE...ESPECIALLY ACROSS CENTRAL SOUTH DAKOTA.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 331 AM CST THU MAR 3 2016
AN EXTENDED WARMUP IS IN STORE FOR THE REGION AS WE MOVE INTO THE
MEDIUM AND THROUGH THE EXTENDED PORTIONS OF THE FORECAST. A MODEST
UPPER WAVE WILL TRACK THROUGH THE NORTHERN PLAINS FRIDAY.
GENERALLY...MOISTURE WILL BE LIMITED WITH THIS WAVE...AND SHOULD
KEEP ANY PRECIPITATION THROUGH THE FIRST HALF OF FRIDAY ON THE
LIGHT SIDE. RAIN MAY BE THE PREDOMINATE PRECIPITATION FORM...BUT
WOULD NOT RULE OUT A FEW SNOWFLAKES MIXING IN ESPECIALLY ALONG THE
BUFFALO RIDGE AREA OF SW MINNESOTA.
SURFACE HIGH PRESSURE WILL SLIDE ACROSS THE AREA BY SATURDAY
MORNING...SIGNALING A RETURN OF WARMER SOUTHERLY FLOW FOR THE
REMAINDER OF THE WEEKEND AND INTO NEXT WEEK. TEMPERATURES WILL BEGIN
TO WARM ON SATURDAY...BUT LINGERING SNOW MAY KEEP READINGS DOWN A
COUPLE DEGREES FROM THEIR POTENTIAL LEVELS. BY SUNDAY...GUSTY
SOUTHWESTERLY WINDS SHOULD PUSH READINGS THROUGH THE 50S...WITH 60S
POSSIBLE IN MANY AREAS. STRATUS REMAINS A CONCERN FOR SUNDAY...AND
IT MAY HAMPER HIGHS JUST A BIT IF IT DEVELOPS AS ADVERTISED BY THE
GFS.
AN UPPER TROUGH LIFTING OUT OF THE FOUR CORNERS REGION OF THE US
WILL AMPLIFY SOUTHWESTERLY FLOW IN THE LOWER LEVELS...BRINGING AN
INCREASING RISK FOR LIGHT SHOWERS OR DRIZZLE BY MONDAY MORNING.
INSTABILITY WILL BEGIN TO INCREASE AHEAD OF THIS UPPER TROUGH LATER
ON MONDAY...AND WILL BRING AND INCREASING RISK FOR THUNDERSTORMS TO
THE CWA BY MONDAY AFTERNOON AND EVENING. HIGHEST INSTABILITY LVLS
REMAIN NEAR THE MO RIVER VALLEY...AND CAPPING LAYER REMAINS IN
PLACE AS THE FRONT SLIDES INTO THE AREA...BUT GIVEN AMPLITUDE OF
SHEAR...COULD NOT RULE OUT A STRONGER STORM OR TWO INTO MONDAY
NIGHT.
LOW-LVL TROUGH PASSAGE WILL OCCUR MONDAY NIGHT INTO TUESDAY
MORNING...BUT SHOULD IT SLOW DOWN...A LINGERING RISK FOR A FEW
THUNDERSTORMS WILL CONTINUE OVER NW IA AND SW MN TUESDAY MORNING.
OTHERWISE...DEFORMATION PRECIPITATION AREA ON THE BACKSIDE OF THE
ADVANCING TROUGH SHOULD BRING SHOWERS TO THE CWA ON TUESDAY.
IF YOU ARE A FAN OF SPRING...THE OUTLOOK THROUGH NEXT WEEK REMAINS
WARM. ABOVE NORMAL TEMPERATURES LOOK LIKELY THROUGH NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1041 PM CST WED MAR 2 2016
THE 06Z TAF SET WILL REFLECT VFR CONDITIONS IN THE NEAR TERM.
HOWEVER BEHIND A DEPARTING SHORT WAVE...WINDS OFF THE SURFACE WILL
BECOME NORTHERLY WHICH SHOULD USHER IN SOME MVFR CEILINGS INTO THE
AREA APPROACHING 12Z THURSDAY. CONFIDENCE IN THE TAFS CONTINUES TO
BE LOW HOWEVER. FOR INSTANCE THE NAM AND RAP MODEL SOUNDINGS AND
HUMIDITY TIME SECTIONS CONTINUE TO SHOW AN INUNDATION OF LOW
STRATUS ACROSS THE ENTIRE AREA FOR THE REST OF TONIGHT AND THROUGH
THURSDAY. THE PROBLEM IS...THOSE MODELS HAVE THESE CONDITIONS RIGHT
NOW AND THEY ARE NOT OCCURRING. LOOKING BACK AT THE GFS ON
TUESDAY...IT DID A BETTER JOB WITH THE CLOUD FORECAST FOR
WEDNESDAY IN THAT IT WAS MORE OPTIMISTIC DURING THE AFTERNOON AND
EVENING HOURS WEDNESDAY OF KEEPING THE IFR AND MVFR STRATUS AWAY
FROM THIS AREA. THEREFORE RELIED HEAVILY ON THE GFS FOR THE REST
OF TONIGHT AND THURSDAY...AND IT IS SUGGESTING MORE OF AN MVFR
ENVIRONMENT...BRINGING DOWN SOME MVFR CEILINGS CURRENTLY IN NORTH
DAKOTA INTO THIS AREA. AGAIN...TIMING OF THE ARRIVAL OF MVFR
CONDITIONS IS QUESTIONABLE.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...DUX
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1046 PM CST WED MAR 2 2016
.UPDATE...
ISSUED AT 853 PM CST WED MAR 2 2016
THE ORGANIZED AREA OF PRECIPITATION THAT WAS IN SOUTHWEST SD IS
DIVING SOUTHEASTWARD AT THIS POINT INTO NEBRASKA. THAT WAS
EXPECTED. THE NORTHERN BRANCH IN NORTH DAKOTA IS WEAKENING AS IT
TRIES TO MOVE SOUTHEASTWARD. ALL THAT IS LEFT IS A BAND OF MID
LEVEL MOISTURE IN OUR WESTERN ZONES THAT IS ALSO MOVING
SOUTHEASTWARD. AND IT IS LIKELY MOST OF THAT IS NOT REACHING THE
GROUND. THEREFORE ONLY SKITTISH POPS FOR LIGHT SNOW SHOWERS ARE
WARRANTED FOR THE REST OF TONIGHT...AND ITS DOUBTFUL WHETHER ANY
SNOWFALL WOULD ACTUALLY MEASURE. THEREFORE WILL KEEP THE POPS LOW.
LASTLY...WILL ELIMINATE THE CHANCE FOR SCATTERED FLURRIES FOR OUR
EASTERN ZONES THURSDAY MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 300 PM CST WED MAR 2 2016
MAIN WAVE NOW APPEARS TO MOVE SOUTHEAST OFF THE SOUTHWEST CORNER OF
THE AREA TONIGHT. SOME UPPER SUPPORT APPEARS TO SPREAD TO THE EAST
OVER THE MISSOURI RIVER AREA BUT ALL MODELS ARE DEPICTING
PRECIPITATION BECOMING ORGANIZED EAST OF THE AREA. EXPECT
PRECIPITATION TONIGHT TO BE SCATTERED AND QUITE LIGHT...INCLUDING
SOUTHWEST MINNESOTA WHERE BEFORE WE WERE GOING WITH LIKELY POPS.
TEMPERATURES ALOFT APPEAR COOLER FOR TONIGHT THAT WE WERE LOOKING
AT YESTERDAY...SO DESPITE THE VERY LIGHT NATURE OF THE PRECIPITATION
AND THE RESULTING MINIMAL EVAPORATIONAL COOLING...SEE A VERY MINIMAL
FREEZING RAIN CHANCE WHERE COOLING IS FAST ENOUGH OVER THE SOUTHWEST
HALF OF THE AREA EARLY THIS EVENING. OTHERWISE SOME LIGHT RAIN
SOUTHWEST EARLY OTHERWISE PRECIPITATION...IF ANY...SHOULD BE MOSTLY
LIGHT SNOW. ACCUMULATIONS WILL STAY BELOW A HALF INCH.
AS THE UPPER WAVE PASSES A LOW LEVEL FLOW OF COOL AND MOIST AIR
SHOULD ASSURE A LOT OF LOW STRATUS OVER THE AREA ESPECIALLY NORTH
AND EAST. THIS SHOULD DEVELOP STRONGLY LATER TONIGHT AND BE STUBBORN
ABOUT DISSIPATING THURSDAY. AM ALLOWING FOR THE START OF BREAKING UP
BY THURSDAY AFTERNOON BUT EXPECT SKIES TO BE MOSTLY CLOUDY AT BEST.
TEMPERATURES WILL COOL INTO THE 20S TONIGHT AND WARM TO THE 30S
THURSDAY...EXCEPT 40 PLUS FAR SOUTHWEST. NOT A LOT OF DIURNAL RANGE
WITH ALL THE CLOUDS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 300 PM CST WED MAR 2 2016
THURSDAY NIGHT INTO FRIDAY WILL SEE A WAVE APPROACH FROM THE
NORTHWEST BUT WILL STRUGGLE TO PRODUCE TOO MUCH IN THE WAY OF
PRECIPITATION DUE TO A LACK OF LOW LEVEL MOISTURE. WILL HAVE LOW END
CHANCE POPS IN PLACE ACROSS HIGHWAY 14 INTO SOUTHWEST MINNESOTA WITH
SMALLER CHANCES TO THE SOUTHWEST. THE BETTER CHANCES SHOULD BE LATE
FRIDAY MORNING THROUGH THE AFTERNOON AND SHOULD MAINLY BE IN THE
FORM OF LIGHT RAIN. WITH A VERY GRADUALLY INCREASING SOUTHERLY FLOW
AND CLOUD COVER LOWS WILL NOT BE TOO COLD AND SHOULD BE MAINLY MID
TO UPPER 20S.
AS THE WAVE MOVES THROUGH CLOUDS WILL DECREASE FROM THE WEST AND
ALLOW FOR SOME DECENT WARMING. THIS SHOULD BE A BIG MELTING DAY FOR
AREAS WEST OF INTERSTATE 29...AS HIGHS CLIMB INTO THE MID TO UPPER
40S ALONG THE JAMES RIVER VALLEY AND TO 50 TO 55 INTO SOUTH CENTRAL
SD.
A SHOT OF COOL AIR WILL SPREAD SOUTH FRIDAY NIGHT AND AT THIS TIME
APPEARS TO BE A BIT OVERDONE ON THE GFS COMPARED TO OTHER MODELS. SO
AT THIS TIME WILL LEAN TOWARDS MID TO UPPER 20S FOR LOWS.
SATURDAY LOOKS TO BE A VERY NICE DAY AS HIGH PRESSURE MOVES THROUGH
AND SOUTHERLY FLOW STARTS TO DEVELOP. TO EASTERN CWA WILL STILL HAVE
SOME SNOW TO GET RID OF SO WILL KEEP HIGHS TEMPERED BACK A BIT
THERE...BUT ALLOW FOR 50S ALONG AND WEST OF THE JAMES RIVER VALLEY.
IN THE OUTER PERIODS...SUNDAY THROUGH WEDNESDAY...A SIGNIFICANT
CHANGE IN PATTERN IS STILL EXPECTED AS RIDGING ALOFT GRADUALLY
SHIFTS EAST WHILE A TROUGH DEEPENS OVER THE WESTERN THIRD OF THE
UNITED STATES. THIS WILL BRING MUCH MORE MOIST AIR IN THE LOW LEVELS
THAN HAS BEEN SEEN FOR QUITE AWHILE ALONG WITH A SUSTAINED SOUTHERLY
FLOW FROM ABOUT SUNDAY INTO TUESDAY. TEMPERATURES WILL BE WELL ABOVE
NORMAL...ESPECIALLY WITH REGARDS TO LOWS...AND A FEW WARM LOW
TEMPERATURE RECORDS ARE LIKELY TO FALL. THE BEST CHANCE FOR THIS
WILL BE MONDAY MORNING AND TUESDAY MORNING. ALONG WITH THE INCREASED
WARMING AND MOISTURE IN THE LOW LEVELS WILL BE A THREAT FOR A FEW
THUNDERSTORMS. AT THIS TIME THE BETTER CHANCE FOR THIS LOOKS TO BE
MONDAY NIGHT BUT IF THE SYSTEM IS SLOW ENOUGH EXITING ON TUESDAY THE
EASTERN THIRD OF THE CWA...MAINLY SW MINNESOTA AND NW IOWA...WOULD
SEE AN ADDITIONAL THREAT. NOT OUT OF THE QUESTION TO SEE A FEW
SEVERE STORMS NEAR THE MISSOURI RIVER MONDAY NIGHT BUT THE BETTER
CHANCE WILL BE TO THE SOUTH. WHILE EVERYTHING WOULD NEED TO COME
TOGETHER JUST RIGHT...DUE TO THE POTENTIAL FOR A LOT OF LOW TO MID
LEVEL SHEAR A FEW SEVERE THUNDERSTORMS WOULD ALSO BE POSSIBLE
TUESDAY AFTERNOON...BUT AT THIS TIME THAT THREAT APPEARS TO BE EAST
OF THIS AREA. COOLER WEATHER WILL SETTLE BACK INTO THE AREA
WEDNESDAY BUT STILL MILD FOR EARLY MARCH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1041 PM CST WED MAR 2 2016
THE 06Z TAF SET WILL REFLECT VFR CONDITIONS IN THE NEAR TERM.
HOWEVER BEHIND A DEPARTING SHORT WAVE...WINDS OFF THE SURFACE WILL
BECOME NORTHERLY WHICH SHOULD USHER IN SOME MVFR CEILINGS INTO THE
AREA APPROACHING 12Z THURSDAY. CONFIDENCE IN THE TAFS CONTINUES TO
BE LOW HOWEVER. FOR INSTANCE THE NAM AND RAP MODEL SOUNDINGS AND
HUMIDITY TIME SECTIONS CONTINUE TO SHOW AN INUNDATION OF LOW
STRATUS ACROSS THE ENTIRE AREA FOR THE REST OF TONIGHT AND THROUGH
THURSDAY. THE PROBLEM IS...THOSE MODELS HAVE THESE CONDITIONS RIGHT
NOW AND THEY ARE NOT OCCURRING. LOOKING BACK AT THE GFS ON
TUESDAY...IT DID A BETTER JOB WITH THE CLOUD FORECAST FOR
WEDNESDAY IN THAT IT WAS MORE OPTIMISTIC DURING THE AFTERNOON AND
EVENING HOURS WEDNESDAY OF KEEPING THE IFR AND MVFR STRATUS AWAY
FROM THIS AREA. THEREFORE RELIED HEAVILY ON THE GFS FOR THE REST
OF TONIGHT AND THURSDAY...AND IT IS SUGGESTING MORE OF AN MVFR
ENVIRONMENT...BRINGING DOWN SOME MVFR CEILINGS CURRENTLY IN NORTH
DAKOTA INTO THIS AREA. AGAIN...TIMING OF THE ARRIVAL OF MVFR
CONDITIONS IS QUESTIONABLE.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...MJ
SHORT TERM...
LONG TERM...08
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
351 PM EST THU MAR 3 2016
.SYNOPSIS...
LOW PRESSURE WILL MOVE QUICKLY TRACK FROM THE MISSISSIPPI VALLEY
TONIGHT...TO THE COAST OF NORTH CAROLINA FRIDAY MORNING. FOLLOWING
A BRIEF PERIOD OF HIGH PRESSURE FRIDAY NIGHT...ANOTHER LOW WILL
MOVE FROM THE NORTHERN PLAINS TO THE MID ATLANTIC REGION BY
SUNDAY. A LARGE HIGH WILL COVER THE REGION ON MONDAY.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 340 PM EST THURSDAY...
WINTER WEATHER ADVISORY WAS IN EFFECT FOR A LARGE PART OF THE
FORECAST AREA.
SOIL TEMPERATURES RANGED FROM THE MID 30S IN THE NORTHWEST COUNTY
WARNING AREA TO THE MID 40S IN THE SOUTHEAST COUNTY WARNING
AREA...WITH THE EXCEPTING OF UPPER 20S IN THE NORTHWEST NORTH
CAROLINA MOUNTAINS. A FEW OTHER FACTORS WILL INFLUENCE SNOW
AMOUNTS TOO.
AS LOWER LEVELS SATURATE TEMPERATURES WILL COME DOWN AND DEW POINTS
WILL COME UP. FOLLOWED THIS NON DIURNAL TREND TO ESTABLISH MINIMUM
TEMPERATURES TONIGHT. BUFKIT FORECAST SOUNDING SUPPORTED SNOW
FORMATION AT UPPER LEVELS BUT SURFACE AND NEAR SURFACE WET BULB
TEMPERATURES ALONG AND EAST OF THE BLUE RIDGE WERE AT OR SLIGHTLY
ABOVE FREEZING FOR A FEW HOURS OVERNIGHT. THIS WILL LIMIT SNOW
ACCUMULATION IN THE EAST. THE EXCEPTION IS A BAND OF HIGHER QPF
POTENTIAL FROM CHARLOTTE COUNTY VIRGINIA TO ROCKINGHAM COUNTY
NORTH CAROLINA WHERE QPF WILL BE LOCALLY ENHANCED AND THE
DEEPENING LOW MAY PROVIDE ENOUGH LIFT SNOWFALL RATES TO OVERCOME
MELTING. CONFIDENCE IS ONLY MODERATE WITH THIS OUTCOME.
WINDS AT LOWER LEVEL BACK TO THE SOUTH AHEAD OF THE LOW BUT DO NOT
HAVE A GOOD SOUTHEAST COMPONENT BEFORE THE MAIN LOW BEGINS TO DEEPEN
RAPIDLY OFF OF THE OUTER BANKS. HRRR AND LOCAL WRF ARE SIMILAR WITH
THE LOCATION AND TIMING OF THE PRECIPITATION. THESE MODELS BRING ONE
BATCH OF SNOW ACROSS THE NORTHERN HALF OF THE COUNTY WARNING AREA
LATE THIS AFTERNOON INTO EARLY THIS EVENING...WITH PRECIPITATION
FILLING IN ACROSS THE SOUTHERN COUNTY WARNING AREA A FEW HOURS
LATER...THEN SHOWING AN AXIS OF POTENTIALLY HEAVIER SNOW FROM
CHARLOTTE COUNTY VIRGINIA TO ROCKINGHAM COUNTY NORTH CAROLINA LATE
TONIGHT. IN GENERAL WILL FOLLOW THIS TIMING AND PLACEMENT
THROUGH FRIDAY MORNING.
BASED ON THE EXPECTED LIQUID EQUIVALENT AMOUNTS...SNOWFALL
AMOUNTS SUPPORT AN ADVISORY BUT NOT A WARNING. SNOW WILL IMPACT
THE EVENING COMMUTE IN MOUNTAIN LOCATIONS AND BASED ON THE
TIMING...FAR EASTERN COUNTIES OF THE FORECAST AREA MAY STILL BE
GETTING SNOW DURING FRIDAY MORNINGS PEAK TRAVEL TIME.
BY FRIDAY AFTERNOON COLD UPPER TROF AND COLD AIR ALOFT ARE WELL EAST
OF THE FORECAST AREA WITH 500 MB HEIGHTS ALREADY BEGINNING TO RISE.
UPPER JET ROUNDS BASE OF THE TROF THEN INTENSIFIES RESULTING IN
SOME STRONGER LIFT OVER EASTERN VIRGINIA AND NORTH CAROLINA
OVERNIGHT.
WILL HAVE SOME CLEARING AND SUN DURING THE AFTERNOON...ESPECIALLY IN
THE EAST ON FRIDAY. THIS WILL MEAN TEMPERATURES WILL BE CLOSE TO
MAV VALUES FOR MAXIMUM TEMPERATURES.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 315 PM EST THURSDAY...
THE DEEPENING CLIPPER SYSTEM SHOULD DEPART OFFSHORE ON FRIDAY
NIGHT...AND ALLOW ANY UPSLOPE MOISTURE OVER SOUTHEAST WEST VIRGINIA
TO SUBSIDE. CLOUDS WILL REMAIN PREVALENT AS ONE MORE CLIPPER SYSTEM
APPROACHES FROM THE GREAT LAKES ON SATURDAY. THE MODELS PIN ITS
ARRIVAL WITHIN THE AFTERNOON HOURS. IT APPEARS CONSIDERABLY WEAK
WITH JUST A 1016 MB LOW. THE 12Z GFS KEEPS MOST OF THE MOISTURE
CONFINED TO AREAS WEST OF THE BLUE RIDGE...WHERE THE HIGHEST POPS
WERE KEPT IN THIS UPDATE. LIGHT RAIN SHOWERS SHOULD CHANGE TO SNOW
SHOWERS BY SATURDAY NIGHT WITH LITTLE IF ANY ACCUMULATION.
BREEZY NORTHWEST WINDS ARE POSSIBLE FOR SATURDAY NIGHT INTO SUNDAY
MORNING...AS THE CLIPPER SYSTEM HEADS EAST OF THE CWA. THE HIGHER
RIDGETOPS MAY GUST UP TO 30 MPH...BUT IT APPEARS THAT NO HEADLINES
FOR WIND WILL BE NEEDED DUE TO WEAK COLD AIR ADVECTION AND MINIMAL
PRESSURE RISES BEHIND THIS SYSTEM. AS IT DEPARTS OFFSHORE ON
SUNDAY...HIGH PRESSURE SHOULD BUILD OVER THE MID ATLANTIC. IT MAY
TAKE UNTIL LATER IN THE DAY FOR SKIES TO FINALLY CLEAR ALONG THE FAR
WESTERN PORTIONS OF THE CWA.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 330 PM EST WEDNESDAY...
BY MONDAY...IT WILL SEEM LIKE THE ATMOSPHERE FLIPPED A SWITCH FROM
WINTER TO SPRING. SURFACE HIGH PRESSURE SHOULD ANCHOR ALONG THE EAST
COAST...WHILE 500 MB HEIGHTS BUILD TOWARD 580 DAM OVERHEAD. THESE
FACTORS WILL START A NOTEWORTHY WARMING TREND. HIGHS FOR WEDNESDAY
AND THURSDAY COULD EASILY REACH THE 60S AND 70S. MEANWHILE...A LOW
PRESSURE SYSTEM WILL ORGANIZE OVER THE CENTRAL PLAINS IN ASSOCIATION
WITH AN UPPER LEVEL TROUGH MOVING TOWARD TEXAS. THIS TROUGH IS
PROJECTED TO BECOME A CUT OFF LOW...BUT ITS FORWARD PROGRESS WILL BE
SLOWED BY THE UPPER LEVEL RIDGE OVER FLORIDA. EVENTUALLY...THE WARM
FRONT FROM THE LOW PRESSURE SYSTEM MAY REACH THE MID ATLANTIC TO
SPARK A CHANCE OF SHOWERS LATER IN THE WORK WEEK.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
AS OF 1235 PM EST THURSDAY...
LOW PRESSURE SYSTEM TRACKING FROM THE MIDDLE AND LOWER MISSISSIPPI
VALLEY TO THE COAST OF NORTH CAROLINA BY FRIDAY MORNING WILL
SPREAD SNOW INTO THE AREA TONIGHT. MEDIUM TO HIGH CONFIDENCE ON
TIMING WITH A GOOD CONSENSUS IN THE MODELS THAT SNOW WILL BEGIN AT
KBLF/KLWB/KBCB/KROA/KLYH 20Z/3PM AND 00Z/7PM. RAIN OR A MIX OF
RAIN AND SNOW WILL BEGIN AT KDAN AROUND 00Z/7PM. LOWER CONFIDENCE
IN THE AMOUNT OF SNOW. WITH THE SNOW...CEILINGS AND VISIBILITIES
WILL BE IFR TO LIFR OVERNIGHT.
ONCE THE LOW MOVES TO THE EAST...WINDS WILL BECOME NORTHWEST. SNOW
WILL END IN THE EAST AFTER 09Z/4AM BUT SNOW SHOWERS WILL PERSIST
AT KLWB AND KBLF THROUGH MUCH OF FRIDAY. HIGH CONFIDENCE THERE
WILL BE LITTLE IMPROVEMENT IN CEILINGS AT THOSE SITES. CEILINGS
WILL LIFT TO VFR WITH BREAKS IN THE CLOUD COVER BY AFTERNOON EAST
OF THE BLUE RIDGE.
EXTENDED DISCUSSION...
FRIDAY NIGHT WILL BE A BRIEF WINDOW OF VFR BEFORE ANOTHER FAST
MOVING CLIPPER SYSTEM PASSES JUST NORTH OF THE REGION SATURDAY
PROVIDING ANOTHER ROUND OF MVFR AND POSSIBLE LIGHT PRECIPITATION
TO THE MOUNTAINS. HIGH PRESSURE BUILDS OVERHEAD WITH VFR
CONDITIONS SUNDAY THROUGH TUESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR VAZ007-
009>020-022>024-032>035-043>047-058-059.
NC...WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NCZ001>004-
018-019.
WV...WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR WVZ042>044-
507-508.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...PW
LONG TERM...PW
AVIATION...AMS/KK
AREA FORECAST DISCUSSION...UPDATED
NWS PORTLAND OR
730 PM PST FRI MAR 4 2016
.SYNOPSIS...THE COLD FRONT THAT IS CURRENTLY BRINGING RAIN TO THE
COAST WILL PUSH INLAND THIS EVENING SPREADING RAIN TO THE REST OF
NORTHWEST OREGON AND SOUTHWEST WASHINGTON. SURFACE LOW PRESSURE
MOVING UP THE COAST WILL ALSO BRING A PERIOD OF STRONG WINDS TO THE
COAST LATE FRIDAY EVENING AND OVERNIGHT. ANOTHER DEVELOPING LOW
PRESSURE SYSTEM WILL LIKELY BRING MORE RAIN TO THE REGION SATURDAY
AND POSSIBLY STRONG WINDS...PARTICULARLY TO THE COAST AGAIN. SNOW
LEVELS WILL LIKELY DROP TO THE CASCADE PASSES SATURDAY NIGHT FOR A
FEW INCHES OF ACCUMULATION BY SUNDAY MORNING. SHOWERS CONTINUE
THROUGH MONDAY WITH POSSIBLY AN AFTERNOON THUNDERSTORM OR TWO.
ADDITIONAL WET WEATHER WILL LIKELY ARRIVE TOWARDS THE MIDDLE TO
LATTER HALF OF NEXT WEEK.
&&
.EARLY UPDATE...RELEASED A QUICK UPDATE TO THE FORECAST FOR
TONIGHT...ACCOUNTING FOR THE SLOWER INLAND PROGRESSION OF THE RAIN.
INLAND VALLEYS AND CASCADES MAY SEE A COUPLE SPRINKLES OR AREAS OF
LIGHT RAIN...BUT MOST OF THE EVENING SHOULD STAY DRY EAST OF THE
COAST RANGE. THE SAME FEATURE DELAYING THE RAIN INLAND IS ALSO
DELAYING THE WIND ALONG THE COAST...A WEAK WAVE OF LOW PRESSURE HAS
DEVELOPED ALONG THE FRONT NEAR 39N/127W. WITH THIS SYSTEM HEADED
TOWARD NORTHERN CA AND ROBBING SOME OF THE SOUTHERLY FLOW...AM
BECOMING INCREASINGLY SKEPTICAL THAT THE HIGH WIND WARNING WILL
VERIFY ALONG THE COAST. HOWEVER...WILL LET THE WARNING RIDE FOR THE
TIME BEING AND WILL TAKE A CLOSER LOOK BEFORE THE REGULARLY
SCHEDULED EVENING PACKAGE GOES OUT. WEAGLE
/PREV DISC ISSUED 322 PM FRI MAR 4 2016/
.SHORT TERM...TONIGHT THROUGH MONDAY...A LARGE LOW PRESSURE AREA
COVERING THE GULF OF ALASKA WILL SEND MULTIPLE SECONDARY LOWS AND
ASSOCIATED FRONTAL SYSTEMS ACROSS THE REGION OVER THE NEXT FEW DAYS.
A COLD FRONT WILL BRING MORE RAIN TO THE COAST THIS AFTERNOON BEFORE
SPREADING INLAND THIS EVENING. KRTX AND KLGX RADARS CONTINUE TO SHOW
SOME LIGHT RAIN OVER MAINLY THE NORTH COAST THIS AFTERNOON WITH KAST
MEASURING 0.05 INCHES IN THE LAST HOURS. MEANWHILE...SATELLITE
IMAGERY CONTINUES TO REVEAL A DEVELOPING SURFACE LOW MOVING NORTH
OVER THE SOUTHERN OREGON OFFSHORE WATERS NEAR 125 W. THIS LOW HELPED
STALL THE COLD FRONT THIS MORNING...BUT AS IT CONTINUES TO MOVE NORTH
THIS EVENING THE FRONT WILL PUSH INLAND. THE 12Z OPERATIONAL MODELS
AND THE 18Z NAM CONTINUES TO SHOW THE LOW BOTTOMING OUT NEAR 995 MB
AS IT PASSES JUST WEST OF THE NORTHERN OREGON AND SOUTHERN WASHINGTON
WATERS LATER THIS EVENING. MODELS CONTINUE TO SHOW THE PRESSURE
GRADIENT OPENING UP LATER THIS EVENING WHICH WILL BRING A SURGE OF
HIGH WINDS TO THE MAINLY THE BEACHES AND HEADLANDS AROUND 10 PM
TONIGHT...WITH GUSTS TO 65 MPH LIKELY. WINDS LOOK TO QUICKLY FALL
BELOW 50 MPH SHORTLY AFTER MIDNIGHT TONIGHT AS THE LOW CONTINUES TO
PUSH NORTH AND WEAKEN BEFORE MAKING LANDFALL OVER BRITISH COLUMBIA.
WILL MAINTAIN THE HIGH WIND WARNING AS IS...BUT WE MAY BE ABLE TO
DROP IT BY 2 AM SATURDAY.
WILL SEE A BRIEF PERIOD OF POST FRONTAL SHOWERS DEVELOP WEST OF THE
COAST RANGE LATE TONIGHT AHEAD OF ANOTHER SERIES OF FRONTAL SYSTEMS
THAT WILL IMPACT THE REGION ON SATURDAY. THIS SYSTEM LOOKS TO FOLLOW
A SIMILAR EVOLUTION TO TODAY`S SYSTEM...ALBEIT WITH A MUCH MORE
COMPLICATED SURFACE PATTERN. WARM FRONTAL RAIN LOOKS TO RETURN TO THE
COAST EARLY SATURDAY AFTERNOON...WITH RAIN SPREADING INLAND IN THE
EVENING. WITH SUCH A SHORT BREAK BETWEEN SYSTEMS SNOW LEVELS LOOK TO
GENERALLY REMAIN ABOVE 6000 FT THROUGH MUCH OF SATURDAY. WITH REGARDS
TO THE COMPLICATED SURFACE PATTERN...MODELS CONTINUE TO SHOW TWO
SECONDARY LOWS DEVELOPING SATURDAY MORNING OVER THE NORTHERN
CALIFORNIA WATERS NEAR 130 W. BOTH LOWS LOOK TO DEEPEN TO AROUND 975
MB AS THEY MOVE NORTH STRADDLING 130 W. DESPITE THE LOW REMAINING
FURTHER OFFSHORE THAT TODAY`S SYSTEM WE COULD STILL SEE A PERIOD OF
HIGH WINDS ALONG THE COAST AND BREEZY CONDITIONS INLAND. WILL GO
AHEAD AND ISSUE A HIGH WIND WATCH FOR THE COAST...WITH GUSTS TO 60
MPH POSSIBLE SATURDAY AFTERNOON THROUGH EARLY SUNDAY MORNING. SNOW
LEVELS WILL FINALLY FALL BELOW PASS LEVEL LATE SATURDAY AS THE COLD
FRONT PUSHES EAST OF THE CASCADES.
THE AFOREMENTIONED LARGE LOW PRESSURE AREA FINALLY MOVES ONSHORE ON
SUNDAY...WITH THE BASE OF THE TROUGH PASSING OVER THE PACIFIC
NORTHWEST. THIS WILL HELP SUPPORT SHOWERS ACROSS THE FORECAST AREAS
SUNDAY AND MONDAY. COULD ALSO SEE A PERIOD OF THUNDERSTORMS ON SUNDAY
AS THE COLD CORE DRIFTS OVER THE FORECAST AREA. THIS COLD CORE WILL
ALSO ALLOW SNOW LEVELS TO FALL TO AROUND 3000 FT BY SUNDAY
EVENING...WITH 3 TO 6 INCHES OF NEW SNOW POSSIBLE IN THE CASCADES
SUNDAY AND MONDAY. /64
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...AN UPPER LEVEL TROUGH AND
ONSHORE FLOW WILL CONTINUE SHOWERS MONDAY NIGHT. TUESDAY MORNING
WILL BE BETWEEN SYSTEMS WITH SHOWERS RAPIDLY DECREASING UNDER BRIEF
RIDGING. THE NEXT PACIFIC FRONT WILL BRING A RETURN OF RAIN AND
MOUNTAIN SNOW TUESDAY AFTERNOON WITH SNOW LEVELS AROUND 3500 FEET.
THERE IS POTENTIAL FOR AN ATMOSPHERIC RIVER EVENT WEDNESDAY AND
THURSDAY WITH A SURFACE LOW (AND ASSOCIATED FRONT) TAPPING INTO A
SWATH OF 1.10 TO 1.4 INCHES OF PRECIPITABLE WATER. INTEGRATIVE VAPOR
TRANSPORT SHOWS THE BEST CHANCE FOR HEAVY RAIN ACROSS SW
OREGON...BUT THINK NW OREGON AND SW WASHINGTON CAN STILL GET A
DECENT SOAKING. SNOW LEVELS WILL INITIALLY START AROUND 3500 FEET
TUESDAY NIGHT...THEN RAPIDLY RISE TO AROUND 5500 FEET WEDNESDAY. TJ
&&
.AVIATION...SOME SHOWERS ALONG THE COAST THIS AFTERNOON BUT THE
ENTIRE AREA IS VFR. COULD START TO SEE SOME MVFR ALONG THE COAST
WITH STEADIER RAIN AROUND 00Z...PUSHING INTO THE VALLEY BY AROUND
03Z. VFR RETURNS AFTER 10Z AT THE COAST AND AFTER ABOUT 12Z OR 13Z
INLAND AS RAIN MOVES OUT OF THE AREA. WINDS ALONG THE COAST WILL
PICK UP THIS EVENING OUT OF THE SOUTH...DROPPING OFF EARLY
SATURDAY MORNING.
KPDX AND APPROACHES...VFR WITH HIGH CLOUDS. WILL SEE CIGS LOWER
TO NEAR 5000 FT THIS EVENING...WITH LIGHT RAIN AND POTENTIAL FOR
MVFR CONDITIONS INCREASING AFTER 03Z. WINDS GUSTY OUT OF THE EAST
ON EASTERN APPROACHES. BOWEN
&&
.MARINE...WINDS AND SEAS HAVE DROPPED OFF SLIGHTLY THIS AFTERNOON
AS A COLD FRONT HAS STALLED ACROSS THE MARINE WATERS. LOW PRESSURE
WELL OFF THE SW OREGON COAST WILL PUSH TOWARD THE LOCAL WATERS
THROUGH THE EVENING AND HELP TO PUSH THE FRONT ONSHORE WHILE
INCREASING WINDS AND SEAS AGAIN. SEAS WILL PUSH 25 FT LATE THIS
AFTERNOON AND EVENING WITH WINDS OUT OF THE SOUTH AT AROUND 40 KT
WITH GUSTS ABOVE 50 KT. ONCE THE FRONT MOVES ONSHORE AND THE LOW
PASSES BY...WINDS WILL SHIFT SW AND EASE...WITH SEAS DROPPING BACK
INTO THE MID TEENS SATURDAY MORNING.
A VERY SIMILAR SITUATION LOOKS LIKE IT IS SETTING UP FOR SATURDAY
AFTERNOON AND EVENING WITH ANOTHER LOW PRESSURE SYSTEM MOVING UP
THE COAST FROM THE SOUTHWEST. THIS IS A A STRONGER LOW BUT STAYS
SLIGHTLY FARTHER OUT SO WINDS AND SEAS WILL LIKELY BE JUST A BIT
LESS THAN WITH THE SYSTEM TODAY. HOWEVER THERE IS STILL THE
POTENTIAL FOR SOME STORM GUSTS SO HAVE ISSUED A STORM WATCH FOR
THE WATERS OFF THE COAST OF CENTRAL OREGON. ALSO ISSUED A GALE
WATCH FOR THE WATERS OFF THE N OREGON AND S WASHINGTON COASTS FOR
THE SAME TIME PERIOD LATE SATURDAY AFTERNOON AND EVENING.
CONFIDENCE IS MODERATE FOR THIS SYSTEM...SO WILL BE KEEPING A
CLOSE EYE ON ITS DEVELOPMENT OVER THE NEXT 24 HOURS.
THE REST OF THE FORECAST PERIOD LOOKS ACTIVE WITH PERIODS OF
GALES AND SEAS REMAINING IN THE TEENS. HOWEVER THERE IS NOTHING IN
THE REST OF THE 5-DAY FORECAST THAT LOOKS AS STRONG AND THIS
EVENING`S AND TOMORROW EVENING`S SYSTEMS. BOWEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING FROM 9 PM THIS EVENING TO 4 AM PST SATURDAY
FOR CENTRAL OREGON COAST-NORTH OREGON COAST.
HIGH SURF ADVISORY UNTIL 3 AM PST SATURDAY FOR CENTRAL OREGON
COAST-NORTH OREGON COAST.
HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH LATE SATURDAY
NIGHT FOR CENTRAL OREGON COAST-NORTH OREGON COAST.
WA...HIGH WIND WARNING FROM 9 PM THIS EVENING TO 4 AM PST SATURDAY
FOR SOUTH WASHINGTON COAST.
HIGH SURF ADVISORY UNTIL 3 AM PST SATURDAY FOR SOUTH WASHINGTON
COAST.
HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH LATE SATURDAY
NIGHT FOR SOUTH WASHINGTON COAST.
PZ...GALE WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT
60 NM.
STORM WARNING FROM 6 PM THIS EVENING TO 1 AM PST SATURDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT
60 NM.
GALE WARNING UNTIL 6 PM PST THIS EVENING FOR COASTAL WATERS
FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
STORM WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING
FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT
60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
6 AM PST SATURDAY.
&&
$$
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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.
[top]
Area Forecast Discussion
National Weather Service Spokane WA
715 PM PST FRI MAR 4 2016
.SYNOPSIS...
A series of weather disturbances are expected this weekend. These
storms will result in significant rain and mountain snow. Cooler
temperatures with lingering showers will persist Monday and
Tuesday. A very wet pattern looks to then set up toward the end of
next week.
&&
.DISCUSSION...
Updated the forecast to increase pops for tonight as the short
term models like the RUC are trending wetter and bringing in some
of the rain a bit earlier overnight. /Pelatti
&&
.AVIATION...
00Z TAFs: VFR cigs/vsby will prevail through 12z Saturday. The
next in a series of weather systems will bring increasing moisture
to the region after 03z tonight with -ra possible at KEAT after
09z spreading to the region and Taf locations by 15Z. Stratiform
rain is expected to linger in the region through the end of the
TAF period. /JDC
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 43 53 45 51 34 48 / 60 80 100 90 20 40
Coeur d`Alene 41 54 43 50 34 49 / 60 80 100 100 30 40
Pullman 43 54 45 50 36 48 / 60 80 90 90 20 50
Lewiston 46 58 48 55 39 53 / 60 60 80 80 40 40
Colville 38 53 43 54 32 50 / 50 60 100 100 30 40
Sandpoint 37 49 41 48 33 47 / 40 90 100 100 40 40
Kellogg 38 49 41 44 31 45 / 60 80 90 100 20 50
Moses Lake 42 58 46 58 34 52 / 50 40 100 20 20 30
Wenatchee 39 53 40 55 34 49 / 60 50 100 20 20 40
Omak 38 51 42 52 32 48 / 80 20 100 60 30 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
242 AM CST SAT MAR 5 2016
.SHORT TERM...(Today)
ISSUED AT 241 AM CST SAT MAR 5 2016
Patchy fog will affect central Illinois ahead of an advancing
cold front early this morning. The fog will clear by mid-morning as
cold front departs into Indiana by 11 am. Little to no precipitation
is expected with the frontal passage in central Illinois, except for
possibly a few sprinkles in areas northeast of Champaign to
Danville. Winds will shift from southwest to northwest behind the
front, and become breezy with gusts to 25 mph at times later this
morning and this afternoon.
The latest HRRR and RAP guidance are pointing towards enough
residual low level moisture behind the front for mostly cloudy skies
to linger through at least mid-afternoon. Breaks will eventually
develop in the cloud layer due to turbulent mixing of dry mid-level
air toward the surface. Areas southwest of Springfield to Mattoon
will have the best chances of seeing sunshine earlier, but even
northeast areas should see sunshine break through later this
afternoon. Even limited late afternoon sunshine should help high
temperatures reach the mid 40s north of I-74, with lower 50s for
areas from Jacksonville to Effingham to Lawrenceville.
&&
.LONG TERM...(Tonight through Friday)
ISSUED AT 241 AM CST SAT MAR 5 2016
Mild and wet period shaping up for much of the upcoming week, as
upper flow finally trends more toward the southwest. Main issue will
be with the rains, as a frontal boundary will be draped over the
state part of the time, and will limit some of the rainfall north of
it around midweek.
High pressure will quickly pass through the Midwest tonight, and
southerly winds will be in place by Sunday morning and become a bit
gusty. This will bring temperatures well into the 50s, with some 60
degree readings possible over the southwest CWA. Some WAA-type
precip expected to develop by afternoon west of the Illinois border,
but forecast soundings in our area quite parched below 700 mb until
evening, and thus will keep the daytime hours dry albeit with
increasing clouds. Have limited mentionable PoP`s Sunday night to
west of I-55, with most of the energy tracking into northwest
Illinois.
On Monday, southerly winds expected to gust from 25-30 mph, pushing
temperatures well into the 60s. During this time, an upper trough
will be digging southward along the California coast, closing off a
low over the Baja. Nice moisture surge coming northward from the
Gulf of Mexico will combine with a wave/front in the northern stream
to gradually increase rain chances from west to east across the
state. Reasonable agreement among the models through about Tuesday
evening with the cold front being just to our northwest. Waves of
low pressure will surge northeast along the front bringing periods
of heavier rain, but how far south the front makes it first will be
key. The ECMWF is slowest in exiting the rain (not until Thursday
evening over the southeast CWA), while the GFS and Canadian show
periodic surges of rain until Thursday morning. Went with
categorical PoP`s (80%) for most areas east of I-55 Tuesday night
through Wednesday night. WPC progs and blended model guidance
suggesting potential for 3-4 inches of rain through the week in this
area, subject to the oscillations of the front. Hydrologic Outlook
product is being used to address this heavy rain concern for the
time being.
The upper low will only slowly drift through northern Mexico, cut
off from the northern flow through much of the week. Late in the
period, the GFS and ECMWF show this low finally ejecting northeast,
although the GFS is much faster in bringing the frontal boundary
back north. With the front position still a significant question,
PoP`s generally remain in place over most of the forecast area into
Friday. Temperatures north of the front will cool a bit mid week,
but still be mid-upper 50s for highs.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 1125 PM CST FRI MAR 4 2016
A cold front, currently over east central Iowa will track across
our area Saturday morning. Forecast soundings and last few runs
of the HRRR model indicate a deterioration in cigs and vsbys
after 06z until the front shifts east of the area after 12z.
Subsidence in the wake of the upper wave should bring cigs back
to MVFR or even low VFR by afternoon. Once the rain band shifts
to our east after 06z, there may be enough lift for some drizzle
at our BMI and CMI locations but coverage too limited to include
in the TAFs at this time.
Surface winds will be southerly at 10 to 15 kts overnight and
then become southwest towards dawn at 5 to 10 kts, and then shift
into the northwest in the 12z to 15z time frame with speeds of 12
to 17 kts with a few gusts around 23 kts thru 21z before winds
diminish quickly from a northerly direction around 00z.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...Geelhart
AVIATION...Smith
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1131 PM CST FRI MAR 4 2016
.UPDATE...
ISSUED AT 830 PM CST FRI MAR 4 2016
Another fast moving shortwave to our northwest will sweep across
the region late tonight accompanied by scattered rain showers
which may mix with a little sleet and light snow across our
north for about an hour or two. The cold front, currently over
central Iowa, will track through our area after midnight taking
the threat for rain with it as it moves to our east by dawn
Saturday. Southerly flow ahead of the front will help to keep
temperatures rather steady in the mid 30s to around 40 through
the evening before falling off towards dawn Saturday. Update
already sent out to address precip timing and type across our
northern counties, as a result, no additional updates needed at
this time.
&&
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 320 PM CST FRI MAR 4 2016
SURFACE HIGH SITUATED OVER THE REGION PROVIDING FOR DRY/QUIET
CONDITIONS THIS AFTERNOON...WITH A MAJORITY OF THE CWA OBSERVING
SUNNY TO PARTLY CLOUDY SKIES. THE EXCEPTION THIS AFTERNOON IS
STILL THE FAR WESTERN CWA NEAR THE JACKSONVILLE AREA WHERE LOW
STRATUS IS STILL SITUATED. HOWEVER...EXPECT CLOUD COVER TO BEGIN
INCREASING THIS AFTERNOON INTO THE EVENING AHEAD OF A COUPLE OF
PIECES OF ENERGY AND ATTENDANT SURFACE TROUGH/FRONTAL BOUNDARY
DROPPING SOUTHEAST THROUGH THE REGION.
MOST GUIDANCE KEEPING THE BULK OF ANY ASSOCIATED PRECIP TO THE
NORTH AND NORTHEAST OF THE AREA TONIGHT...WHERE THE STRONGER/MORE
ORGANIZED FORCING WILL RESIDE. STRONG WAA ALREADY NOTED
APPROACHING NORTHWEST AND WEST CENTRAL ILLINOIS WILL ALSO DROP
SOUTHEAST AND EVEN STRENGTHEN AS IT FOCUSES OVER THE CWA THIS
EVENING. THIS SHOULD ALLOW THE PREVALENT DRIER AIR IN PLACE TO
BECOME OVERCOME WITH LIGHT PRECIP TO AT LEAST BE OBSERVED OVER A
FEW HOUR WINDOW TIME FRAME LATE THIS EVENING TO JUST AFTER
MIDNIGHT. WITH THIS PRECIP EXPECTED TO BE LIGHT...BRIEF AND LOW IN
COVERAGE...HAVE MAINTAINED CHANCE POPS FOR THE ENTIRE AREA
TONIGHT. PRECIP SHOULD REMAIN IN THE FORM OF RAIN TONIGHT FOR MOST
AREAS GIVEN THE WARMER BOUNDARY LAYER CONDITIONS AND WARM WEDGE
ALOFT WITH THE PERSISTENT WAA. HOWEVER...A FEW SNOW FLAKES MAY BE
OBSERVED INITIALLY WITH WET BULBING. THIS COULD OCCUR OVER THE FAR
NORTHEAST CWA FROM LACON TO DANVILLE...BUT SHOULD BE BRIEF AS THE
ENTIRE COLUMN FURTHER WARMS AND WITH THE LOSS OF CRYSTALS. TEMPS
DURING THIS TIME WILL LIKELY REMAIN ABOVE FREEZING...WITH ANY
FREEZING RAIN NOT EXPECTED. TEMPS MAY BEGIN TO APPROACH THE
FREEZING MARK LATE TONIGHT...BUT DO EXPECT ANY PRECIP TO HAVE
EXITED BY THIS TIME.
THESE MID/UPPER LEVEL FEATURES WILL EXIT TO THE EAST
SATURDAY...WITH SURFACE RIDGING EXPECTED TO OCCUR ONCE AGAIN
ACROSS THE REGION. THIS SHOULD BRING ANOTHER PERIOD OF DRY WEATHER
SATURDAY AND SATURDAY NIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 346 PM CST FRI MAR 4 2016
A QUIET START TO THE PERIOD IS EXPECTED EARLY NEXT WEEK WHILE
UPPER LEVEL RIDGING IS OCCURRING. BACKING LOW/MID LEVEL FLOW IN
ADVANCE OF UPPER LEVEL TROUGH OVER THE WESTERN HALF OF THE CONUS
WILL HELP STEER IN A WARMER AIRMASS TO THE REGION...WITH ABOVE
NORMAL TEMPS EXPECTED BY SUNDAY AND MONDAY. THIS WILL START A
PERIOD OF WARMER/ABOVE NORMAL TEMPS FOR THE REGION INTO NEXT WEEK.
WITH THIS WARMER AIRMASS IN PLACE...MOISTURE WILL BEGIN TO MAKE A
RETURN TO THE AREA...WITH THE PATTERN BECOMING MORE CONDUCIVE OF
PERIODIC SHOWER DEVELOPMENT. INCREASING CHANCES FOR SHOWERS WILL
RETURN BY SUNDAY NIGHT INTO MONDAY AS SOME WEAKER MID LEVEL
IMPULES PUSH THROUGH THE MID MISSISSIPPI VALLEY.
HOWEVER...CHANCES REALLY INCREASE CLOSER TO MID WEEK AS LARGE
SCALE FORCING RAMPS UP AHEAD OF ADVANCING UPPER LEVEL TROUGH OVER
THE CENTRAL CONUS. SHOWERS AND A FEW THUNDERSTORMS WILL BECOME
LIKELY DURING THIS TIME WITH THE POSSIBILITY OF REPEATED ROUNDS OF
RAIN. THIS WILL BE DUE IN PART TO A STATIONARY BAROCLINIC ZONE IN
PLACE SETTING UP THE POSSIBILITY FOR HEAVY RAINFALL...AND WILL
NEED TO CONTINUE TO MONITOR THIS PERIOD FOR THIS POTENTIAL.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 1125 PM CST FRI MAR 4 2016
A cold front, currently over east central Iowa will track across
our area Saturday morning. Forecast soundings and last few runs
of the HRRR model indicate a deterioration in cigs and vsbys
after 06z until the front shifts east of the area after 12z.
Subsidence in the wake of the upper wave should bring cigs back
to MVFR or even low VFR by afternoon. Once the rain band shifts
to our east after 06z, there may be enough lift for some drizzle
at our BMI and CMI locations but coverage too limited to include
in the TAFs at this time.
Surface winds will be southerly at 10 to 15 kts overnight and
then become southwest towards dawn at 5 to 10 kts, and then shift
into the northwest in the 12z to 15z time frame with speeds of 12
to 17 kts with a few gusts around 23 kts thru 21z before winds
diminish quickly from a northerly direction around 00z.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Smith
SHORT TERM...RODRIGUEZ/KREIN
LONG TERM...RODRIGUEZ/KREIN
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1044 PM CST FRI MAR 4 2016
.SHORT TERM...
200 PM CST
THROUGH SATURDAY...
ALL REMAINS ON TRACK FOR A QUICK SHOT OF SNOW TONIGHT ESPECIALLY
ALONG AND NORTH OF I-80. THE PRIMARY IMPACT LOOKS TO BE SHARPLY
REDUCED VISIBILITY FOLLOWED BY A QUICK COATING OF SNOW ON SOME
PAVED SURFACES.
THE CENTER OF THE MAIN CLIPPER SHORT WAVE IS IN WESTERN MINNESOTA
EARLY THIS AFTERNOON. AS ITS DRIVING JET SPREAD INTO OUR REGION
THIS EVENING...HEIGHT FALLS AND ASSOCIATED LIFT WILL MAXIMIZE OVER
WISCONSIN AND NORTHERN ILLINOIS. STEEPER MID-LEVEL LAPSE RATES
OBSERVED ON UPSTREAM MORNING SOUNDINGS AND EARLY AFTERNOON
AIRCRAFT DATA FROM OMAHA WILL CONTINUE TO SPREAD EASTWARD WITHIN
THE WARM ADVECTION ZONE SOUTH OF THE VORTICITY CENTER. AS THIS
CATCHES UP TO THE LIFT AND SATURATION...THE AREA OF PRECIPITATION
PRESENTLY IN MN/NORTHERN IA SHOULD SHOW SOUTHEAST EXPANSION AND
PROBABLY INTENSIFICATION DURING THE EARLY TO MID EVENING WHICH
CORRELATES TO WHEN IT IS OVER THE AREA.
HAVE ONLY MADE FURTHER REFINEMENTS TO HOURLY TIMING OF
PRECIPITATION WHICH LOOKS TO BE MAINLY WET SNOW THIS EVENING
ESPECIALLY IN NORTHEAST ILLINOIS AND FAR NORTHWEST INDIANA. ONSET
OF PRECIPITATION COULD BRIEFLY BE A MIX WITH RAIN...AND TOWARD
I-39 IT COULD REMAIN A MIX OR EVEN JUST RAIN SHOWERS THIS EVENING.
BECAUSE OF THE QUICK MOVEMENT OF THE FORCING AND FOCUS...THE
SNOWFALL LOOKS TO LAST TWO HOURS OR LESS IN MOST LOCATIONS...WITH
THE MODERATE INTENSITY EVEN A SHORTER SPAN. CONVECTIVE ALLOWING
MODELS CONTINUE TO SUPPORT THIS IN THEIR REFLECTIVITY...
VISIBILITY...AND HOURLY SNOWFALL FORECASTS. THE PRIMARY TIMING
FOR THE CHICAGO METRO LOOKS TO BE BETWEEN 9 PM AND MIDNIGHT.
WETTER QUALITY OF THE SNOW AND TEMPERATURES OF 31-35 SHOULD LIMIT
MUCH FOR ACCUMULATION ON PAVEMENT...THOUGH GRASSY SURFACES WILL
PROBABLY SEE A QUICK COAT IN NORTH OF I-80 COMMUNITIES. SOUTH OF
I-80 MORE LIMITED TIME AND FORCING FOR SATURATION WILL PROVIDE
MORE VIRGA /RADAR ECHOES NOT REACHING THE GROUND/ THAN
PRECIPITATION...SO NO ACCUMULATION FORECAST.
LOSS OF ICE HAPPENS RAPIDLY BY MIDNIGHT WHICH MAKES SENSE GIVEN
UPSTREAM SATELLITE TRENDS. LOW-LEVEL SATURATION AND LIFT STILL ARE
PROVIDED ON RAP AND NAM SOUNDINGS EVEN THROUGH DAYBREAK. SO
CONTINUE FORECAST DRIZZLE CHANCES. THE TEMPERATURES SHOULD BE
INCHING UP LATE TONIGHT SO NOT TOO CONCERNED ON FREEZING DRIZZLE
BUT DO INDICATE THE BRIEF POSSIBILITY IN THE FORECAST WHERE OUR
DETERMINISTIC TEMPERATURE FORECASTS OUR 30-32 FOR A FEW HOURS.
HAVE TRENDED MORE CLOUDY FOR SATURDAY ESPECIALLY FOR THE EASTERN
HALF OF THE CWA. HAVE DONE SO AS THE CLIPPER BROADENS TO OUR
NORTHEAST AND KEEPS CYCLONIC FLOW ACROSS THE REGION. CLEARING
SHOULD OCCUR FROM WEST-TO-EAST SOMETIME IN THE AFTERNOON THROUGH
IT COULD TAKE UNTIL EARLY SATURDAY EVENING. HAVE HIGHS AROUND
NORMAL WITH 40 EAST TO 45 WEST.
MTF
&&
.LONG TERM...
213 PM CST
SATURDAY NIGHT THROUGH FRIDAY...
A SHIFT TOWARDS A WARM AND ACTIVE SPRING-LIKE PATTERN IS EXPECTED
TO OCCUR LATE IN THE WEEKEND INTO EARLY NEXT WEEK BRINGING
UNSEASONABLY WARM CONDITIONS AS WELL AS PERIODIC CHANCES FOR
SHOWERS AND THUNDERSTORMS.
BY SATURDAY NIGHT...SURFACE RIDGE IS EXPECTED TO BUILD ACROSS
NORTHERN ILLINOIS AND NORTHWEST INDIANA BRINGING QUIET CONDITIONS
BUT FAVORABLE FOR RADIATIONAL COOLING...AND WHAT LOOKS TO BE OUR
COLDEST NIGHT OVER THE UPCOMING WEEK. FORECASTING LOWS IN THE 20S
ACROSS THE FORECAST AREA...HOWEVER WOULDNT BE SURPRISED TO SEE A
FEW OF THE TYPICAL COLD SPOTS DIPPING INTO THE TEENS.
HIGH PRESSURE WILL SHIFT TO OUR EAST SUNDAY WITH SOUTHERLY FLOW
OVERSPREADING THE REGION. THE HIGH IS PROGGED TO BECOME ANCHORED
JUST OFF THE SOUTHEASTERN ATLANTIC COAST WHILE UPPER LEVEL PATTERN
CONTINUES TO AMPLIFY WITH STRONG EAST COAST UPPER RIDGE
DEVELOPING BY THE MIDDLE OF NEXT WEEK AND DEEP TROUGHING
DEVELOPING ACROSS THE WESTERN CONUS. LOCALLY THIS WILL MEAN A
WARMING TREND THROUGH TUESDAY WHEN TEMPERATURES ARE FORECAST TO
RISE INTO THE MID 60S ACROSS NORTHERN ILLINOIS AND NORTHWEST
INDIANA. AS DEEP TROUGHING MOVES OVER THE MID SECTION OF THE
COUNTRY...WE WILL SET THE STAGE FOR SEVERE WEATHER TO OCCUR ACROSS
PORTIONS OF THE PLAINS AND MIDWEST EARLY NEXT WEEK AND WHILE ITS
TOO EARLY TO HONE IN ON SPECIFICS FOR SEVERE WEATHER...MODELS DO
SHOW INSTABILITY BUILDING THIS FAR NORTH SO A THUNDERSTORM MENTION
IS INCLUDED IN THE FORECAST FOR NOW...MAINLY ON TUESDAY FOR OUR
AREA. UPPER LOW EXPECTED TO CUT OFF ACROSS THE DEEP SOUTH AROUND
MIDWEEK AND EVENTUALLY MEANDER ACROSS THE MIDWEST LATE IN THE
WEEK OR NEXT WEEKEND. DETAILS REMAIN UNCLEAR AT THIS POINT BUT IT
DOES APPEAR WE WILL GENERALLY STAY IN A WARMER AND WETTER PATTERN
LATE IN THE WEEK INTO NEXT WEEKEND.
DEUBELBEISS
&&
.AVIATION...
FOR THE 06Z TAFS...
MAIN FORECAST CONCERNS FOR TAFS IS WITH MVFR/POTENTIAL IFR CIGS
AND MVFR VIS IN DRIZZLE AND LIGHT FOG OVERNIGHT.
MID-LEVEL DISTURBANCE WHICH BROUGHT SNOW TO THE REGION DURING THE
MID-LATE EVENING HOURS WAS MOVING THROUGH THE AREA AT MIDNIGHT.
FAIRLY DISTINCT BACK EDGE TO MORE ORGANIZED SNOW...ROUGHLY FROM
KMKE TO KVYS/KPIA AT 0440Z. THUS IT APPEARS MOST SNOW WILL END BY
06Z...PERHAPS SHORTLY AFTER AT GYY. IR SATELLITE IMAGERY DEPICTS
EXTENSIVE AREA OF LOW CLOUDS EXTENDING UPSTREAM INTO THE UPPER
MISSISSIPPI VALLEY...WHICH MODEL FORECAST SOUNDINGS INDICATE WILL
LIKELY LINGER ACROSS THE TERMINALS INTO SATURDAY. PERSISTENT LIFT
ABOVE THIS LOW LEVEL MOISTURE WILL LIKELY PRODUCE DRIZZLE FOR THE
REMAINDER OF THE OVERNIGHT HOURS...WITH A BRIEF WINDOW OF FREEZING
DRIZZLE POSSIBLE AFTER MIDNIGHT BEFORE TEMPS SLOWLY RISE ABOVE
FREEZING DURING THE PRE-DAWN HOURS. SINKING AIR BEHIND THE
DEPARTING WAVE SHOULD LIMIT ANY PRECIP BY SATURDAY MORNING...
THOUGH GRADUALLY RISING MVFR CIGS LIKELY TO LINGER THROUGH A GOOD
PORTION OF THE DAY BEFORE SCATTERING LATE.
SOUTH WINDS NEAR 10 KT WILL SHIFT WEST BY MORNING AND THEN
NORTHWEST WITH GUSTS NEAR 20 KT SATURDAY MORNING. WINDS THEN
DIMINISH AND BECOME NORTH-NORTHEAST SATURDAY EVENING AS SURFACE
HIGH PRESSURE APPROACHES.
RATZER
&&
.MARINE...
213 PM CST
A CLIPPER LIKE SNOW SYSTEM WILL DROP ACROSS THE UPPER MIDWEST AND
WESTERN GREAT LAKES REGION TODAY WITH MODERATE SOUTHERLY FLOW OF
20 TO 25 KT EXPECTED AHEAD OF THIS SYSTEM THIS EVENING AND
TONIGHT. THE LOW WILL CROSS OVER THE SOUTHERN HALF OF LAKE
MICHIGAN ON SATURDAY WITH WINDS TURNING NORTHERLY BEHIND...THEN
DIMINISHING AS HIGH PRESSURE BEGINS TO BUILD OVERHEAD FOR SATURDAY
NIGHT. THE HIGH WILL CONTINUE TO THE SOUTHEAST STATES AND
EVENTUALLY SET UP NEAR BERMUDA WHERE IT WILL REMAIN ANCHORED MUCH
OF THE UPCOMING WEEK WHICH WILL HELP DRIVE A MAJOR PATTERN CHANGE
ACROSS THE REGION. LOW PRESSURE DEVELOPS OVER THE PLAINS SUNDAY
INTO EARLY NEXT WEEK WITH SOUTHERLY FLOW RAMPING BACK UP AGAIN TO
AROUND 30 KT SUNDAY. MODERATE SOUTHERLY FLOW OF 20 TO 25 AND
OCCASIONALLY 30 KT WILL CONTINUE THROUGH TUESDAY HELPING SPREAD AN
UNSEASONABLY WARM AND MOIST AIRMASS INTO THE GREAT LAKES. THE HIGH
DEWPOINTS ARE EXPECTED TO RESULT IN AREAS OF FOG DEVELOPING OVER
THE LAKE. ALSO CANNOT RULE OUT SOME THUNDERSTORMS...PARTICULARLY
ON TUESDAY.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS JACKSON KY
102 AM EST SAT MAR 5 2016
.UPDATE...
ISSUED AT 1058 PM EST FRI MAR 4 2016
THE LOW CLOUDS HAVE BROKEN UP AS THE LOW LEVEL FLOW HAS BECOME
MORE WESTERLY UNDER A WEAK AREA OF RIDGING IN BETWEEN A DEPARTING
SYSTEM AND AN APPROACHING UPPER LEVEL DISTURBANCE AND COLD FRONT.
MODEL TIME HEIGHT SECTIONS SUGGEST BREAKS OR EVEN CLEAR SKIES FOR
THE NEXT 5 HOURS OR SO BEFORE CLOUDS SHOULD THICKEN AND LOWER IN
ADVANCE OF THE COLD FRONT. THIS SHOULD LEAD TO CONTINUED FOG
DEVELOPMENT AND WITH TEMPERATURES NEAR FREEZING PATCHY BLACK ICE
IS A CONCERN ON BRIDGES AND OVERPASSES. ELSEWHERE NORTH OF THE
MTN PARKWAY WHERE SNOW REMAINS ON THE GROUND MELTING ON FRIDAY LED
TO WET ROADS IN SOME LOCATIONS. THIS COULD ALSO LEAD TO SOME
PATCHY BLACK ICE. THE POTENTIAL FOR BLACK ICE HAS BEEN ADDED TO
THE HWO. OTHERWISE...AS FOR THE SYSTEM ARRIVING ON SATURDAY...
SCATTERED SHOWERS POSSIBLY ARRIVING AS EARLY AS 9 AM TO 10 AM EST
PER THE 0Z GFS AND RECENT HRRR RUN...OR LATER PER RAP AND NAM
GUIDANCE. ANY INITIAL PRECIPITATION COULD FALL AS A RAIN AND SNOW
MIX BEFORE WARM ADVECTION THROUGHOUT THE COLUMN IN ADVANCE OF THE
COLD FRONT TURNS ANY PRECIPITATION TO ALL RAIN BY MIDDAY.
UPDATE ISSUED AT 630 PM EST FRI MAR 4 2016
WEAK UPSLOPE FLOW AND MOIST LOW LEVELS IS LEADING TO SOME DRIZZLE
OR VERY LIGHT RAIN...AND OR HIGH ELEVATION FLURRIES ACROSS THE
REGION. THIS SHOULD CONTINUE MAINLY ACROSS THE SOUTHEAST PART OF
THE CWA UNTIL LATE EVENING BEFORE THE LOW LEVEL FLOW BECOMES MORE
WESTERLY AND THE MOISTURE BECOMES MORE SHALLOW. PATCHY FOG SHOULD
ALSO BE COMMONPLACE...BOTH ON THE RIDGES AND IN SOME VALLEY
LOCATIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 345 PM EST FRI MAR 4 2016
LATEST GOES WV IMAGERY SHOWS THE UPPER LEVEL TROUGH AXIS PUSHING
OFF TO THE EAST ALLOWING FOR SOME TEMPORARY DRYING AT MID LEVELS.
AT LOW LEVELS...HOWEVER...MOISTURE AND CLOUDS WILL LIKELY REMAIN
IN PLACE THROUGH THE OVERNIGHT PERIOD...WITH THE POTENTIAL FOR
SOME SCOURING OUT OF THE CLOUDS IN NORTHWESTERN LOCATIONS. A FEW
STRAY SHOWERS ARE ALSO POSSIBLE THIS EVENING. LOWS WILL STAY IN
THE LOWER 30S.
GOES IR IMAGERY SHOWS MID AND HIGH LEVEL CLOUDS STARTING TO
SPREAD INTO THE REGION AHEAD OF THE NEXT SHORTWAVE TROUGH. THIS
TROUGH WILL DROP DOWN FROM THE NORTHERN PLAINS TONIGHT AND PASS
THROUGH EASTERN KENTUCKY DURING THE DAY TOMORROW...PROVIDING
CHANCES OF MAINLY RAIN SHOWERS. DUE TO THE COLDER TEMPERATURES IN
THE NORTHERN COUNTIES...KEPT A BRIEF CHANCE OF A RAIN/SNOW MIX
EARLY ON. RAIN SHOWERS WILL CONTINUE THROUGHOUT THE DAY AND THEN
GRADUALLY PUSH OFF TO THE EAST SATURDAY NIGHT. HIGHS WILL REBOUND
INTO THE UPPER 40S AND LOWER 50S NORTH...WITH SOME MID 50S NOTED
IN THE SOUTHWEST.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 405 PM EST FRI MAR 4 2016
THE MODELS HAVE COME INTO BETTER AGREEMENT ALOFT THROUGH THE
EXTENDED PORTION OF THE FORECAST. THEY ALL DEPICT THE DEPARTURE OF
A SHORTWAVE TROUGH TO THE SOUTHEAST ON SUNDAY WITH RIDGING
BUILDING INTO THE AREA THROUGH MONDAY MORNING. AROUND THIS TIME A
DEEP AND BROAD TROUGH STARTS TO SET UP OVER THE WESTERN UNITED
STATES. THIS TROUGH SETTLES DEEP INTO SOUTHERN CALIFORNIA AND
INTO NORTHERN MEXICO WHILE SENDING SPURS OF ENERGY NORTHEAST INTO
THE SOUTHERN PLAINS. WITH TIME...THE RIDGE BUILDS STRONGER OVER
THE SOUTHERN APPALACHIANS WHILE THE WESTERN TROUGH CLOSES OFF OVER
THE MOUNTAINS OF NORTHWESTERN MEXICO. THIS WILL SET UP BROAD
SOUTHWEST FLOW INTO THE SOUTHERN PLAINS...ONLY SLOWLY MOVING EAST
THROUGH THE MIDDLE OF THE WEEK. ALL THESE FEATURES TIGHTEN UP INTO
WEDNESDAY WITH MORE RIDGING EAST AND TROUGHING TO THE SOUTHWEST.
THROUGH THE DEEP SOUTH SOUTHWEST FLOW...FROM OVER THE WESTERN
GULF...PLENTY OF ENERGY WILL RUN NORTHEAST INTO THE SOUTHERN
PLAINS AND CENTRAL MISSISSIPPI VALLEY INTO THURSDAY. MEANWHILE...
EAST KENTUCKY WILL BE UNDER THE HEAVY INFLUENCE OF STRONG RIDGING
WHOSE CENTER WILL SLOWLY SLIP SOUTH TO SOUTHERN FLORIDA. THE
CUTOFF SOUTHERN LOW WILL START TO GET PICKED UP BY THE NORTHERN
STREAM LATE IN THE WEEK WITH A BETTER CHANCE OF ENERGY SPILLING
INTO KENTUCKY. FOR FRIDAY...THE MODELS ARE IN GENERAL AGREEMENT
WITH THE BROAD LOW MOVING TOWARD THE MISSISSIPPI DELTA WITH
GENERAL SOUTHERLY FLOW CONTINUING OVER KENTUCKY. DUE TO THE DECENT
MODEL AGREEMENT HAVE FAVORED A GENERAL BLEND FOR THE FORECAST
DETAILS.
SENSIBLE WEATHER WILL FEATURE MODERATING TEMPERATURES ON SUNDAY AS
HIGH PRESSURE CROSSES THE OHIO VALLEY AND WEAK LOW PRESSURE MOVES
AWAY FROM THE AREA. FOLLOWING THIS...THE HIGH MOVES TO THE EAST
COAST AND AS IT DOES SO TEMPERATURES WILL REALLY SOAR REACHING WELL
INTO THE MID 60S BY MONDAY AFTERNOON. THIS PATTERN WILL THEN BE
RATHER STEADY STATE THROUGH THE BULK OF THE WEEK. HIGH PRESSURE
WILL KEEP THE RAINS OF THE WEST AT BAY FOR MOST OF THE CWA DURING
THIS TIME. THIS WILL LIKELY SPARE EAST KENTUCKY FROM THE VERY
HEAVY RAINS THAT WILL BE SETTING UP FOR PARTS OF THE SOUTHERN
PLAINS AND INTO THE WESTERN OHIO VALLEY. EVENTUALLY...THOUGH...
THE PATTERN WILL SHIFT EAST ENOUGH THAT SHOWERS AND POSSIBLE
THUNDERSTORMS WILL MOVE INTO OUR AREA FOR WEDNESDAY AND THURSDAY.
ADDITIONAL SHOWERS CAN BE ANTICIPATED FOR FRIDAY...AS WELL. ALSO
THROUGH IT ALL...TEMPERATURES WILL REMAIN WELL ABOVE NORMAL BOTH
FOR HIGHS AND NIGHTTIME LOWS. THE ONLY CONCERN WILL BE FOR PERHAPS
EXCESSIVE RAINS LATE IN THE WEEK AND BEYOND AS THIS AREA OF VERY
MOIST LOW PRESSURE SLOWLY EDGES INTO THE DEEP SOUTH AND TENNESSEE
VALLEY.
ADJUSTED THE GRIDS FROM THE CR INIT MAINLY TO ACCOUNT FOR DECENT
SMALL RIDGE TO VALLEY TEMPERATURE DIFFERENCES SUNDAY THROUGH
WEDNESDAY NIGHTS. ALSO TWEAKED THE POP GRIDS FOR THE LATTER PART
OF THE PERIOD TO SLOW THE ARRIVAL OF THE HIGHER POPS INTO OUR
WESTERN ZONES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1257 AM EST SAT MAR 5 2016
LOW LEVEL MOISTURE REMAINS ACROSS MUCH OF THE REGION...DESPITE
SOME CLOUDS STARTING TO MOVE IN FROM THE NORTH. AS A RESULT...FOG
CONTINUES ACROSS THE TAF SITES...WITH MOST LOCATIONS AT OR BELOW
AIRPORT MINIMUMS FOR BOTH VIS AND CIG HEIGHTS. EVEN AS CLOUDS
CONTINUE TO OVERSPREAD AHEAD OF OUR NEXT WEATHER SYSTEM...SUBSIDENCE
AND MOISTURE AT THE SURFACE SHOULD REMAIN STRONG ENOUGH TO KEEP
FOG INTACT THROUGHOUT THE NIGHT. CONDITIONS WILL IMPROVE AS DAY
BREAKS AND SCATTERED LIGHT RAIN SHOWERS BEGIN IMPACTING THE
NORTHEASTERN PORTION OF THE STATE BY 12Z...REACHING KSYM BY 14Z
AND MAKING THEIR WAY SOUTHEAST ACROSS THE REST OF THE TAF SITES.
COVERAGE WILL BE SPOTTY...BUT RAIN SHOULD REMAIN LIGHT...SO
CONTINUED WITH VCSH MENTION AT MOST TAF SITES FOR NOW UNDER
GENERALLY MVFR CIGS. RAIN WILL QUICKLY EXIT OVERNIGHT...BUT
ANOTHER SUBSIDENCE/LLVL MOISTURE SET UP WILL LIKELY LEAD TO MORE
FOG DEVELOPMENT ACROSS THE REGION. OVERALL...WINDS SHOULD REMAIN
LIGHT THROUGHOUT THE TAF PERIOD...PREDOMINATELY FROM THE SW BEFORE
BECOMING MORE WRLY BEHIND THE PASSING COLD FRONT AFTER 0Z SUNDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...JVM
LONG TERM...GREIF
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
447 AM EST SAT MAR 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EST SAT MAR 5 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWS A RIDGE OVER THE ROCKIES
AND A TROF OVER ERN NAMERICA. SHORTWAVE THAT BROUGHT SNOW INTO UPPER
MI OVER THE LAST 12HRS OR SO IS TRACKING SE THRU WI. THIS WILL BE
THE FINAL SHORTWAVE TO DROP SE THRU THE AREA BEFORE A TRANSITION TO
A WARM SPLIT FLOW PATTERN WITH ABOVE NORMAL HEIGHTS AND W TO SW FLOW
ACROSS THE UPPER GREAT LAKES NEXT WEEK. RADAR TRENDS OVER THE LAST
COUPLE OF HRS SHOW SNOW DIMINISHING OVER UPPER MI...AND UPSTREAM...
KDLH RADAR SHOWS VERY LITTLE PCPN REMAINING. THERE WERE OBS AND
REPORTS OF SOME -FZDZ EARLIER IN THE NIGHT OVER WRN UPPER MI AND NRN
WI AS THE HEAVIER SNOW DEPARTED. RECENTLY...THERE ARE FEWER OBS
SHOWING UNKNOWN PCPN...SO -FZDZ MAY BE DIMINISHING.
WITH SHORTWAVE CONTINUING SE TODAY...DIMINISHING PCPN WILL END FROM
NW TO SE. SOUTHERLY FLOW ON LAKE MI PERSISTS THRU MID TO LATE
MORNING WHICH SHOULD HELP WEAKLY LAKE ENHANCED SNOW TO LINGER.
THUS...HIGHEST POPS WILL PAINTED OVER THE E THIS MORNING WITH
PERHAPS ANOTHER HALF INCH OR SO OF SNOW ACCUMULATION. TO THE W...
WILL KEEP A MENTION OF -FZDZ/-SN MAINLY IN THE COUNTIES BORDERING WI
FOR THE NEXT FEW HRS. SATELLITE IMAGERY SHOWS CLEARING NOT THAT FAR
AWAY ACROSS NRN LAKE SUPERIOR. WITH HIGH PRES RIDGE BUILDING INTO
THE UPPER GREAT LAKES THIS AFTN...LOW-LEVEL NORTHERLY WINDS AHEAD OF
THE RIDGE WILL DIMINISH. THIS INCREASES THE UNCERTAINTY IN HOW MUCH
CLEARING WILL OCCUR...ESPECIALLY SINCE UPSLOPE FLOW OFF THE LAKE
UNDER A LOWERING INVERSION SHOULD GREATLY SLOW THE CLEARING PROCESS.
KEWEENAW OBVIOUSLY HAS THE BEST CHC OF AT LEAST PARTIALLY CLEARING
OUT TODAY GIVEN THE CLOSE PROXIMITY OF CLEAR SKIES ALREADY EARLY
THIS MORNING. FOR NOW...FCST WILL SHOW A VERY GRADUAL DECREASE IN
CLOUDS FROM THE N AND NW THIS AFTN INTO THIS EVENING.
CLOUD FCST INTO TONIGHT REMAINS A BIT TRICKY. IF THE EXTENSIVE LOW
CLOUDS ACROSS MN/WI PERSIST THRU THE DAY...THESE CLOUDS MAY MOVE
BACK INTO THE AREA TONIGHT ONCE S TO SW FLOW DEVELOPS/INCREASES
AFTER THE HIGH PRES RIDGE PASSES. OTHERWISE...PROVIDED MUCH OF
TODAYS CLOUD COVER DEPARTS BY EVENING...THERE WILL BE AN OPPORTUNITY
FOR TEMPS TO FALL QUICKLY THIS EVENING UNDER LIGHT/CALM WIND. LEANED
FCST TO THE COLDER BIAS CORRECTED REGIONAL/GLOBAL CANADIAN MODELS
DUE TO THEIR NORMAL SUPERIOR PERFORMANCE IN RADIATIONAL COOLING
SITUATIONS. TRADITIONAL COLD SPOTS WILL FALL DOWN INTO THE MID TEENS
IF SKIES ARE MOSTLY CLEAR THIS EVENING.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 349 AM EST SAT MAR 5 2016
ADVERTISED EARLY SPRING PREVIEW IS STILL ON TRACK FOR EARLY NEXT
WEEK AND BEYOND. SUBSTANTIAL WARM ADVECTION KICKS IN ON SUNDAY.
PRESSURE GRADIENT WILL TIGHTEN SIGNIFICANTLY BETWEEN SURFACE
LOW/SHORTWAVE MOVING THROUGH NORTHERN ONTARIO AND HIGH PRESSURE
ALONG THE EAST COAST. 85H TEMPS CLIMB INTO THE PLUS 5 TO 8C RANGE.
EVEN WITH THE STABLE THERMAL PROFILE 92H WINDS ARE FORECAST UP TO 40
KNOTS SO EXPECT WINDS TO BE PRETTY GUSTY. NAM REMAINS
CONSISTENT...AND TO A LESSER EXTENT THE GFS...IN SHOWING ENOUGH
MOISTENING THROUGH THE DAY THAT THERE MAY EVEN BE SOME LIGHT
PRECIPITATION OVER EASTERN AREAS BY LATE IN THE DAY. WILL INTRODUCE
SOME SLIGHT CHANCE POPS ACROSS THE EAST FOR SOME LIGHT RAIN/DRIZZLE.
TEMPS ON SUNDAY WILL CLIMB INTO THE 40S WEST WHILE LAKE MICHIGAN
COOLING WITH THE STRONG SOUTHWESTERLY WINDS WILL KEEP TEMPS IN THE
UPPER 30S ACROSS THE EAST.
THE BEST CHANCES FOR ANY WIDESPREAD PRECIPITATION...ALBEIT
RELATIVELY LIGHT...WILL OCCUR DURING THE MONDAY THROUGH TUESDAY
NIGHT TIME PERIOD. WHILE TEMPERATURES WILL BE WELL ABOVE NORMAL...IT
WILL PROBABLY BE PRETTY GLOOMY DURING THIS PERIOD. CONTINUED WARM
ADVECTION...DEWPOINTS CLIMBING INTO THE 30S AND 40S...AND A MELTING
SNOWPACK WILL YIELD PLENTY OF LOW CLOUDS...PATCHY FOG...AND DRIZZLE.
SHEARING OUT SHORTWAVE EJECTING WEST OF THE AREA ON TUESDAY WITH
SURFACE LOW PASSING NORTHWEST OF LAKE SUPERIOR WILL BRING THE BEST
CHANCE OF RAIN ON TUESDAY. WITH DYNAMICAL FORCING ON THE WANE AND
LINGERING MID LEVEL DRY AIR ANY PRECIPITATION WILL BE PRETTY LIGHT.
AS TRAILING COLD FRONT CROSSES THE AREA LATE TUESDAY AND WITH FAIRLY
STEEP MID LEVEL LAPSE RATES STILL CANNOT RULE THE POSSIBILITY OF A
THUNDERSTORM ALONG THE FRONT. HOWEVER...CAPPING MAY REMAIN TOO
STRONG TO ALLOW ANY DEEP CONVECTION. DESPITE THE CLOUDS
TEMPERATURES WILL APPROACH 50 FOR MANY ON MONDAY AND INTO THE 50S ON
TUESDAY AWAY FROM THE COOLING INFLUENCES OF THE LAKES...ESPECIALLY
LAKE MICHIGAN.
DRIER AIR ALONG WITH SOME COOLING BEHIND THE FRONT WILL ALLOW
PRECIPITATION TO COME TO AN END TUESDAY NIGHT.
FORECAST LOOKS DRY DURING THE WEDNESDAY THROUGH FRIDAY PERIOD. AFTER
A BRIEF COOL DOWN WEDNESDAY...ALTHOUGH STILL ABOVE NORMAL...MILD
PACIFIC AIR WILL RETURN FOR LATE IN THE WEEK WITH DAYTIME TEMPS ONCE
AGAIN APPROACHING 50 FOR MANY BY LATE IN THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1159 PM EST FRI MAR 4 2016
EXPECT IFR TO POSSIBLY LIFR CONDITIONS AT KIWD AND KSAW OVERNIGHT AS
LIGHT SNOW CHANGES TO MIX OF FLURRIES/FZDZ AND CIGS CONTINUE TO
LOWER AS MOISTURE REMAINS TRAPPED IN THE LOW-LEVELS. CONDITIONS AT
KCMX COULD REMAIN PREVAILING MFVR WITH ONLY IFR AT TIMES AS NE FLOW
OVERNIGHT WILL BE MORE OF A DOWNSLOPE FLOW AND ALSO KCMX WILL BE
FARTHER FROM DEEP MOISTURE OF SYSTEM PASSING TO SOUTH. ONCE
THE SYSTEM SLIDES OUT ON SAT...EXPECT IFR TO LOW MVFR DECK TO STAY IN
PLACE INTO AT LEAST EARLY AFTN ALONG WITH LINGERING FLURRIES
POSSIBLE. HIGH PRESSURE MOVING IN LATE AFTERNOON FROM THE WEST SHOULD
ALLOW FOR CONDITIONS TO IMPROVE TO VFR AT KIWD AND KCMX AND TOWARD
EVENING AT KSAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EST SAT MAR 5 2016
EXPECT LIGHT WINDS...MOSTLY UNDER 15KT TO BE THE RULE ACROSS LAKE
SUPERIOR TODAY UNDER A WEAK PRES GRADIENT WITH HIGH PRES RIDGE
ARRIVING IN THE AFTN. PRES GRADIENT WILL THEN TIGHTENT TONIGHT AND
SUN AS THE RIDGE SHIFTS TO THE E COAST AND A LOW PRES MOVES ACROSS
SCNTRL CANADA. S TO SW WINDS WILL RAMP UP TO AS HIGH AS 30KT LATE
TONIGHT AND SUN. NOT OUT OF THE QUESTION THAT A FEW GALE FORCE GUSTS
COULD OCCUR OVER EASTERN LAKE SUPERIOR SUN. WINDS WILL THEN DIMINISH
SUN NIGHT/MON UNDER A WEAKENING PRES GRADIENT. AS LOW PRES TRACKS
FROM THE WESTERN PLAINS MON MORNING TO NORTHERN ONTARIO TUE AND
QUEBEC WED...WINDS WILL AGAIN INCREASE TO 15-25KT AT TIMES TUE/WED.
SOME FOG MAY FORM OVER THE CHILLY WATERS MON NIGHT/TUE AS MOISTER
AIR MOVES INTO THE UPPER LAKES AHEAD OF THE LOW PRES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MZ
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
309 AM EST SAT MAR 5 2016
.DISCUSSION...
LIGHT SNOW OVERSPREAD MUCH OF SE MI OVERNIGHT. SFC OBSERVATIONS AND
RADAR SUGGEST SOME LOCALS /PARTICULARLY SOUTH OF THE I-69 CORRIDOR/
HAVE BEEN EXPERIENCING INTERVALS OF FAIRLY GOOD SNOWFALL RATES. THIS
SNOW IS OCCURRING WITHIN A REGION OF MID LEVEL ISENTROPIC ASCENT
AHEAD OF AN UPPER SHORT WAVE NOW OVER WISCONSIN...AIDED BY A LEAD
SHORT WAVE IMPULSE NOW ROTATING INTO SE MI. THE UPSTREAM MID LEVEL
TROUGH WILL ROTATE INTO THE OHIO VALLEY BY AFTERNOON...WITH THE
ASSOCIATED SFC LOW /OVER CNTRL WISCONSIN AS OF 07Z/ TRACKING INTO
NRN INDIANA BY EARLY AFTERNOON. THE REGIONAL WATER VAPOR LOOP SHOWS
THE AXIS OF DEEP LAYER MOISTURE ALREADY OVER SE MI...WITH MID LEVEL
DRY AIR FAST MOVING INTO SW LOWER MI. THIS LOSS OF MID LEVEL
MOISTURE IS LEADING TO AN ABRUPT END TO THE LIGHT SNOW OVER SW LOWER
ATTM. MODEL RH PROGS AND SOUNDINGS /WITH SUPPORT FROM THE WATER
VAPOR LOOP/ INDICATE THE MID LEVEL DRY AIR WILL OVERSPREAD SE MI BY
12Z. THE RESULTING BRIEF DURATION OF THE SNOW EARLY THIS MORNING
WILL KEEP ACCUMS TO AN INCH OR LESS /WITH THE HIGHEST AMOUNTS SOUTH
OF I-69/.
DESPITE THE LOSS OF MID LEVEL MOISTURE...THERE WILL BE AN ADDITIONAL
INFLUX OF LOW LEVEL MOISTURE /SUB 850MB/ DRIVEN INTO SE MI DURING
THE MORNING. THIS WILL PROVIDE A GOOD SET UP FOR SOME FREEZING
DRIZZLE. THIS AND THE AMOUNT OF FZDZ REPORTS ACROSS WISCONSIN
SUPPORT ADDING AREAS OF FZDZ TO THE MORNING FORECAST. BY THE TIME
THAT CONDITIONS BECOME OPTIMAL FOR FZDZ...SFC TEMPS SHOULD BE
WARMING INTO THE LOWER 30S AND LIKELY ABOVE FREEZING BY NOON. THIS
AND THE POTENTIAL SHORT DURATION OF ANY DRIZZLE WILL SUPPORT HOLDING
OFF ON ANY TYPE OF WINTER WX ADVISORIES FOR THE TIME BEING.
DEEP LAYER MOISTURE WILL ROTATE BACK INTO SE MI THIS AFTERNOON. WITH
SOME STEEP MID LEVEL LAPSE RATES AND DIURNAL INSTABILITY...SNOW
SHOWER ACTIVITY IS POSSIBLE. THE NAM AND HRRR SUGGEST SOME FGEN
DEVELOPMENT ALONG THE MID TROPOSPHERIC FRONT...GENERALLY SOUTH OF
THE M 59 CORRIDOR EARLY IN THE AFTERNOON. THIS WILL NOT ONLY WARRANT
HIGHER POPS IN THESE LOCALS BUT ALSO SUGGEST SOME ADDITIONAL LIGHT
AFTERNOON SNOW ACCUMS /POSSIBLY A HALF INCH/.
SFC HIGH PRESSURE WILL EXPAND ACROSS SE TONIGHT AMIDST RISING MID
LEVEL HEIGHTS IN THE WAKE OF THE DEPARTING UPPER TROUGH. LOW LEVEL
ANTICYCLONIC FLOW AND DRY AIR ADVECTION SHOULD CLEAR THE LOW CLOUDS
OUT LATE IN THE NIGHT...SUPPORTING A BRIEF PERIOD OF DECENT
RADIATIONAL COOLING. IF THIS COOLING OCCURS A LITTLE EARLIER...LATER
SHIFTS WILL HAVE TO CONSIDER ADDING FOG TO THE FORECAST.
LONG WAVE RIDGE AMPLIFICATION ACROSS THE ERN US EARLY NEXT WEEK AND
THE ESTABLISHMENT OF STRENGTHENING SOUTHWEST FLOW FROM THE SRN
PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES WILL SUPPORT A
DRAMATIC WARM UP BEGINNING SUNDAY AND PERSISTING THROUGH AT LEAST
TUESDAY. DESPITE THE SNOW COVER...THE STRONG LOW LEVEL WARM AIR
ADVECTION WITHIN THE WELL MIXED SW FLOW WILL SUPPORT TEMPS ON THE
HIGH END OF GUIDANCE /40S SUNDAY...50S MON...60S TUES/. CONSENSUS
AMONG THE MEDIUM RANGE MODEL SUITE INDICATE BETTER RAINFALL CHANCES
MID TO LATE WEEK AS MUCH DEEPER MOISTURE GETS ADVECTED INTO THE
GREAT LAKES. A GOOD DEAL OF FCST UNCERTAINTY REVOLVES AROUND TIMING
A BACK DOOR COLD FRONT THROUGH THE AREA NEXT WEEK. MODEL SOLUTIONS
DIVERGE WITH RESPECT TO TIMING AND AMPLITUDE OF AN UPPER WAVE
TRACKING ACROSS CANADA WHICH RESULTS IN A LARGE SPREAD IN TIMING
THIS BACK DOOR COLD FRONT INTO SE MI. IT LOOKS AS THOUGH THIS FRONT
WILL MOVE THROUGH SOMETIME IN THE WED TO THURS TIME FRAME AND WILL
HAVE THE POTENTIAL TO BRING MUCH COOLER LAKE MODIFIED BOUNDARY LAYER
AIR INTO THE AREA /WITH WARM MOIST SOUTHWEST FLOW ALOFT STILL
PROVING PERIODIC CHANCES FOR RAIN SHOWERS/.
&&
.MARINE...
WINDS WILL REMAIN LIGHT TODAY...GENERALLY UNDER 10 KNOTS...AS LOW
PRESSURE SLIDES FROM THE WESTERN GREAT LAKES INTO THE OHIO VALLEY
TODAY...AND THEN A RIDGE OF HIGH PRESSURE SHIFTS INTO THE AREA
TONIGHT. LOW PRESSURE TRACKING ACROSS HUDSON BAY AND ONTARIO SUNDAY
INTO SUNDAY NIGHT WILL THEN PROVIDE A TIGHTER SURFACE PRESSURE
GRADIENT OVER THE AREA...CAUSING WINDS TO INCREASE. THE STRONGEST
WINDS LOOK TO OCCUR OVER THE OPEN WATERS OF LAKE HURON...WITH SPEEDS
INTO THE 20 TO 25 KNOT RANGE. GUSTS SHOULD REMAIN BELOW GALE FORCE
HOWEVER AS WARMER AIR SURGING INTO THE AREA WILL PROVIDE A HIGH
DEGREE OF STABILITY OVER THE COLD LAKE WATERS.
&&
.AVIATION...ISSUED 1153 PM EST FRI MAR 4 2016
LIGHT SNOW MOVING IN FROM THE WEST AND STRATUS FROM THE SOUTH WILL
HELP PRODUCE MVFR CONDITIONS DURING THE NIGHT AS THE NEXT LOW
PRESSURE SYSTEM MOVES IN FROM THE MIDWEST. THERE COULD BE A BREAK IN
SNOW SHOWERS OR A MIX OF DRIZZLE/FREEZING DRIZZLE DURING THE MORNING
AS THE LOW APPROACHES. THIS COULD ALSO TURN OUT TO BE JUST FOG WITH
ENOUGH UNCERTAINTY TO HOLD OFF ON FZDZ MENTION IN THE FORECAST FOR
NOW. A RESURGENCE OF SNOW SHOWERS WITH IFR INTENSITY IS THEN
EXPECTED DURING THE AFTERNOON...MAINLY SOUTH OF FNT THROUGH THE DTW
AREA...AS THE LOW TRACKS NEAR TOLEDO. ACCUMULATION AROUND 1 INCH...
LOCALLY 2 WHERE HEAVIER SNOW SHOWERS ARE MORE CONCENTRATED...REMAINS
ON TARGET BEFORE THE SYSTEM EXITS SATURDAY EVENING.
FOR DTW... A SLIGHTLY FASTER TREND FOR MVFR DEVELOPMENT IS EXPECTED
MAINLY DUE TO STRATUS RETURNING NORTHWARD FROM OHIO...BUT ALSO WITH
A FASTER ONSET OF SNOW. SNOW SHOWERS OFF AND ON DURING THE MORNING
COULD ALSO BE MIXED WITH FOG OR FREEZING DRIZZLE. UPSTREAM TRENDS IN
OBSERVATIONS WILL BE NEEDED TO REFINE THE POTENTIAL. AFTERNOON SNOW
SHOWERS WILL HAVE GREATER INTENSITY WITH ABOUT 1 INCH OF
ACCUMULATION BY SATURDAY EVENING.
//DTW THRESHOLD PROBABILITIES...
* MODERATE FOR CEILINGS AOB 5000 FEET OVERNIGHT. HIGH SATURDAY.
* HIGH FOR SNOW AS PRECIPITATION TYPE TONIGHT THROUGH AFTERNOON.
LOW FOR FREEZING DRIZZLE DURING THE MORNING.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
DISCUSSION...SC
MARINE.......HLO
AVIATION.....BT
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS BISMARCK ND
344 AM CST SAT MAR 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CST SAT MAR 5 2016
WARMER...BREEZY...AND DRY CONDITIONS HIGHLIGHT THE SHORT TERM
PERIOD. SOUTHERLY WINDS/WARM AIR ADVECTION DEVELOP TODAY ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. A MINOR COLD FRONT PASSES
THROUGH SATURDAY NIGHT.
THE LATEST WATER VAPOR AND IR IMAGERY LOOP INDICATE MID/UPPER
LEVEL RIDGING OVER THE NORTHERN ROCKIES THIS MORNING WITH
SCATTERED HIGH CLOUDS RIDING ATOP THE RIDGE INTO WESTERN NORTH
DAKOTA. FOG/STRATUS IMAGERY LOOP CONTINUES TO SHOW AN AREA OF LOW
CLOUDS IN THE JAMES RIVER VALLEY. THIS IS FORECAST TO EXIT BY 12Z
SATURDAY. THE TREND WILL BE FOR THE UPPER RIDGE TO SHIFT EAST AND
GRADUALLY FLATTEN/BECOME BROADER THROUGH TONIGHT...AS A PAIR OF
SHORTWAVES PUSH INTO THE RIDGE. THE FIRST SHORTWAVE IS BEST
DEFINED AT 700MB AND CURRENTLY IS LOCATED IN SOUTH CENTRAL
MONTANA. THIS WILL STEADILY MOVE INTO SOUTH CENTRAL NORTH DAKOTA
BY 00Z SUNDAY. NOT EXPECTING ANYTHING SIGNIFICANT AS THERE IS NO
SURFACE LOW REFLECTION. THIS SHORTWAVE WILL MAINLY SERVE TO
FLATTEN THE OVERALL HEIGHT FIELD/RIDGE AXIS AS IT PROPAGATES
THROUGH. THE SECOND SHORTWAVE NOW INTO SOUTHWEST BRITISH COLUMBIA
WILL SLIDE ACROSS SOUTHERN CANADA INDUCING A SURFACE LOW/COLD
FRONT IN SOUTHERN ALBERTA THIS AFTERNOON. IT WILL THEN MOVE EAST
AND GRAZE NORTH DAKOTA SATURDAY NIGHT WITH A WIND SHIFT AND WEAK
COLD AIR ADVECTION.
FOR TODAY...THE CANOPY OF THE 1000-500MB THICKNESS RIDGE HOVERS
OVER THE SOUTHWEST...RESULTING IN THE WARMEST/DRIEST AIR TO RESIDE
HERE. AFTERNOON HIGHS WILL CLIMB INTO THE MID/UPPER 60S SOUTHWEST.
ELSEWHERE EXPECT HIGHS IN THE 50S CENTRAL TO 40S FROM THE TURTLE
MOUNTAINS INTO THE JAMES RIVER VALLEY. UTILIZED A 50/50 COMBINATION
BLEND OF THE HRRR EXPERIMENTAL 2M HOURLY RH FIELD AND OFFICIAL
GRIDDED FORECAST TO YIELD MINIMUM RELATIVE HUMIDITIES IN THE 15
TO 20 PERCENT RANGE SOUTHWEST. THIS SEEMS LOGICAL GIVEN UPSTREAM
FLOW AND RELATED AIRMASS FROM FRIDAY HAVING ADVECTED IN FROM
WYOMING. THE HRRR RH FIELD VERIFIED WELL IN NORTH DAKOTA AS WELL
AS UPSTREAM IN THE LAST 24HR. WINDS TODAY WILL BE WEAKEST IN THE
FAR SOUTHWEST WHERE AFTERNOON RELATIVE HUMIDITIES WILL BE LOWEST.
WINDS WILL STEADILY INCREASE INTO THE BREEZY CATEGORY (15-25MPH)
FOR CENTRAL NORTH DAKOTA THIS AFTERNOON.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 344 AM CST SAT MAR 5 2016
ABOVE-NORMAL TEMPERATURES AND MAINLY DRY WEATHER WILL PREVAIL FOR
THE NEXT WEEK.
ON SUNDAY...DAILY RECORD HIGHS MAY FALL GIVEN 850-MB TEMPERATURES
IN THE 97.5 TO 99TH PERCENTILE FOR THIS TIME OF THE YEAR...NEARLY
FULL SUNSHINE...DRY SOILS...AND DORMANT VEGETATION...ALL OF WHICH
WILL SUPPORT EFFICIENT HEATING. WE ARE STILL CALLING FOR HIGHS IN
THE 60S F IN MOST AREAS AND A FEW 70 F READINGS ARE LIKELY ACROSS
SOUTHWEST AND SOUTH CENTRAL ND. MIXING IS FORECAST TO BE SOMEWHAT
MORE SHALLOW THAN ON SATURDAY BASED ON 00 UTC MODEL SOUNDINGS AND
THAT RAISES A BIT OF CONCERN FOR WARMING....BUT MORE THAN LIKELY
THAT WILL JUST ENSURE WINDS WILL STAY RELATIVELY LIGHT. SUNDAY IS
APT TO BE A TRULY STELLAR EARLY MARCH DAY.
THEREAFTER...A PACIFIC COLD FRONT WILL CROSS THE AREA MONDAY AS A
WEAK SHORTWAVE TROUGH EJECTS ACROSS THE REGION OUT OF A SPLITTING
TROUGH THAT WILL KEEP ITS CORE WELL SOUTH IN TX AND MEXICO. WE DO
HAVE A LOW-GRADE SHOWER CHANCE IN THE FORECAST BEHIND THE FRONT
MONDAY THROUGH EARLY TUESDAY. PROGRESSIVE...QUASI-ZONAL FLOW WILL
THEN OCCUR IN THE NORTHERN STREAM THE MIDDLE PART OF THE WEEK AND
THAT WILL YIELD MAINLY DRY WEATHER. THE 00 UTC GFS AND ECMWF BOTH
SUGGEST RIDGING REBUILDING AGAIN BY LATE WEEK....WITH THE 00 UTC
NAEFS EVEN CALLING FOR 850-MB TEMPERATURE ANOMALIES IN THE 90TH
PERCENTILE BY FRIDAY. THAT IS A SIGNIFICANT SIGNAL IN A LONG-LEAD
ENSEMBLE FORECAST...SUGGESTING HIGHS COULD ONCE AGAIN END UP WELL
INTO THE 60S F /WARMER THAN OUR CURRENT FORECAST/ BY LATE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY)
ISSUED AT 344 AM CST SAT MAR 5 2016
MVFR CIGS AT KJMS WILL LIFT TO VFR BY 12Z SATURDAY. VFR CIGS/VSBYS
THEREAFTER AND ACROSS ALL OTHER TERMINALS THROUGH 12Z SUNDAY.
BREEZY SOUTHERLY WINDS 15-25KT SATURDAY WILL BECOME WEST AT
5-10KT AFTER 06Z SUNDAY AS A WEAK COLD FRONT SLIDES THROUGH.
&&
.FIRE WEATHER...
ISSUED AT 344 AM CST SAT MAR 5 2016
IT APPEARS RIGHT NOW THE PROJECTED FIRE DANGER WILL BE IN THE
HIGH CATEGORY ACROSS SOUTHWEST NORTH DAKOTA TODAY. DESPITE
MINIMUM RELATIVE HUMIDITIES IN THE 15 TO 20 PERCENT RANGE...WINDS
WILL BE LACKING FOR CRITICAL FIRE WEATHER CRITERIA BEING MET.
SUSTAINED SOUTHERLY WINDS WILL WEAKEN THROUGH THE AFTERNOON TO
BETWEEN 10 AND 15 MPH...JUST AS RELATIVE HUMIDITIES REACH THEIR
MINIMUM AS MENTIONED ABOVE. THUS WILL NOT ISSUE ANY HIGHLIGHTS AT
THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KS
LONG TERM...CJS
AVIATION...KS
FIRE WEATHER...KS
AREA FORECAST DISCUSSION...CORRECTED
NWS PORTLAND OR
934 PM PST FRI MAR 4 2016
.SYNOPSIS...A STRONG BUT SLOW MOVING FRONT REMAINS JUST OFF THE
COAST...YIELDING A MOSTLY DRY EVENING FOR THE FORECAST AREA. THIS
FRONT WILL CONTINUE TO SLOWLY MOVE TOWARD THE COAST TONIGHT...
EVENTUALLY SPREADING RAIN ACROSS THE FORECAST AREA LATER TONIGHT AND
SATURDAY MORNING. THE FRONT IS ALSO BRINGING STRONG WINDS TO THE
COASTAL WATERS...WHICH WILL BRIEFLY IMPACT THE IMMEDIATE COAST LATER
TONIGHT. A STRONGER LOW PRESSURE SYSTEM IS EXPECTED TO DEVELOP
OFFSHORE SATURDAY...BRINGING MORE RAIN AND GUSTY WINDS BY SATURDAY
EVENING. COOLER AIR BEHIND THIS SYSTEM WILL CAUSE SNOW LEVELS TO
LOWER TO THE CASCADE PASSES FOR A FEW INCHES OF ACCUMULATION BY
SUNDAY MORNING. SHOWERS CONTINUE SUNDAY AND MONDAY WITH POSSIBLY AN
AFTERNOON THUNDERSTORM OR TWO. ADDITIONAL WET WEATHER WILL LIKELY
ARRIVE TOWARDS THE MIDDLE TO LATTER HALF OF NEXT WEEK.
&&
.SHORT TERM...TONIGHT THROUGH MONDAY...WINDS REMAIN GENERALLY LIGHT
ALONG THE COAST SO FAR THIS EVENING...A STARK CONTRAST FROM THE GALE
FORCE WINDS OCCURRING JUST OFFSHORE. THE DELAY IN WINDS HAS LARGELY
BEEN DUE TO THE DEVELOPMENT OF A WEAK WAVE OF LOW PRESSURE NEAR
40N/127W WHICH IS KEEPING PRESSURE GRADIENTS UNFAVORABLE FOR STRONG
WINDS ALONG THE COAST. THIS WAVE OF LOW PRESSURE IS BECOMING
ABSORBED INTO THE FRONT...WITH THE REMNANT IMPULSE FORECAST BY THE
00Z NAM AND UW WRF-GFS TO LIFT NORTH ALONG THE OREGON COAST
OVERNIGHT TONIGHT. THIS COULD YIELD A BRIEF PERIOD WHERE WINDS REACH
55-65 MPH ALONG THE BEACHES AND HEADLANDS...WHILE THE COASTAL
COMMUNITIES SEE MUCH LIGHTER WINDS. REGARDLESS...CONFIDENCE IS
DWINDLING A BIT ON WHETHER OR NOT THE HIGH WIND WARNING WILL VERIFY
TONIGHT. HOWEVER CONFIDENCE THAT IT WILL NOT VERIFY IS NOT NEARLY
HIGH ENOUGH TO CANCEL AN EXISTING WARNING AT THIS POINT.
THE SAME WAVE OF LOW PRESSURE HOLDING UP THE WINDS ALONG THE COAST
HAS ALSO ALLOWED A MAINLY DRY EVENING ACROSS THE FORECAST AREA ASIDE
FROM SOME SPRINKLES HERE AND THERE. IN FACT...NO RAWS OR ASOS
STATIONS HAVE REPORTED MEASURABLE PRECIPITATION IN THE PAST HOUR IN
OUR CWA. ISSUED A QUICK UPDATE EARLIER TO DECREASE POPS EAST OF THE
COAST RANGE THIS EVENING. 03Z HRRR AND 00Z NAM/GFS STILL SUGGEST THE
FRONT WILL MAKE ENOUGH PROGRESS TOWARD THE COAST TO SPREAD RAIN
INLAND LATER TONIGHT AND SAT MORNING. THE EXISTING FRONT WILL LIKELY
STRETCH AND WEAKEN CONSIDERABLY WHILE OVER WESTERN WA/OR SAT.
THE FRONT WILL LIKELY LEAVE BEHIND PLENTY OF LOW-LEVEL MOISTURE...
AND THERE MAY BE ENOUGH SUN BREAKS OR THINNING IN CLOUD COVER TO
ALLOW SFC TEMPS TO REACH A POINT WHERE THE AIR MASS WILL BE
CONDITIONALLY UNSTABLE UP TO 25 KFT OR SO. WITH STRONG FORCING
EXPECTED TO ARRIVE IN THE FORM OF A DEVELOPING LOW AND NEGATIVELY-
TILTED COLD FRONT...DECIDED IT WOULD BE PRUDENT TO ADD A THUNDER
MENTION TO THE ENTIRE CWA SAT AFTERNOON AND EVENING. ALSO ADJUSTED
TEMPS UPWARDS BY A FEW DEGREES AS THE 00Z GFS SHOWS A THERMAL RIDGE
OF 850 MB TEMPS +8 TO +10 DEG C SPREADING UP NORTH THROUGH THE
WILLAMETTE VALLEY SAT AFTERNOON. BARRING A COMPLETELY CLOUDY DAY WITH
NO SUNBREAKS AT ALL...THIS SHOULD ALLOW MOST LOWLAND LOCATIONS TO
REACH 60 DEGREES SAT AFTERNOON. AS MENTIONED ABOVE...THESE WARMER SFC
TEMPS WILL ASSIST ANY SFC-BASED CONVECTION THAT TRIES TO DEVELOP
ALONG/AHEAD OF THE COLD FRONT COMING IN FROM THE SOUTHWEST.
THE DEVELOPING LOW MENTIONED ABOVE IS SHOWING MORE AND MORE
INDICATION THAT IT IS GOING TO BE THE BIG DOG OF THIS SERIES OF LOWS
BRUSHING THE PAC NW COAST. A VERY WELL-DEFINED NORTHERN STREAM
SHORTWAVE IS EASILY VISIBLE ON WATER VAPOR SATELLITE IMAGERY NEAR
40N/145W. A STRONG PUSH OF COLD AIR BEHIND THIS SYSTEM IS TIGHTENING
THE BAROCLINICITY...WHILE A 160-180 KT JET STREAM FEEDS INTO THIS
SYSTEM. ALL THE INGREDIENTS ARE THERE FOR RAPID CYCLOGENESIS...AND
THE 00Z GFS SHOWS THIS NICELY IN DEVELOPING A 975 MB LOW NEAR
45N/130W BY SAT AFTERNOON WHICH EVENTUALLY BECOMES A 965 MB PARENT
LOW NEAR HAIDA GWAII BY SUN AFTERNOON. MEANWHILE...COLD AIR WILL
CONTINUE TO UNDERCUT THE LOW...DRIVING A STRONG AND VERY SHARP COLD
FRONT INTO THE OREGON COAST LATE SAT AFTERNOON OR SAT EVENING. THE
00Z NAM DEVELOPS ANOTHER SUB-980 MB LOW ALONG THE FRONT NEAR THE
OREGON COAST...WHICH IS POSSIBLE BUT THE DETAILS ARE LIKELY
IMPOSSIBLE FOR THE MODEL TO RESOLVE AT THIS POINT. EITHER
WAY...STRONG COLD ADVECTION FROM THE SOUTHWEST AND PRESSURE RISES
BEHIND THE FRONT ARE LOOKING INCREASINGLY FAVORABLE FOR WINDY
CONDITIONS NOT JUST ALONG THE COAST...BUT INLAND AS WELL SAT EVENING.
WOULD NOT BE SURPRISED IF WE END UP WITH LOW-END ADVISORY GUSTS IN
THE WILLAMETTE VALLEY... THOUGH THIS IS NOT SHOWN AT THIS POINT BY
EITHER THE 00Z NAM OR UW WRF. WILL HOLD GUSTS JUST BELOW ADVISORY
CRITERIA FOR NOW...WITH 30-40 MPH GUSTS IN THE WILLAMETTE VALLEY.
THE HIGH WIND WATCH FOR THE COAST SATURDAY NIGHT STILL LOOKS GOOD.
GIVEN THE TRAJECTORY OF THE LOW...GRADIENTS WILL PROBABLY NOT BE
FAVORABLE FOR STRONG WINDS UNTIL THE FRONT ARRIVES. HOWEVER A STRONG
SURGE OF WIND IS LIKELY ALONG AND AHEAD OF THE FRONT...NOT JUST FOR
THE BEACHES AND HEADLANDS BUT FOR THE COASTAL COMMUNITIES AS WELL.
JUST HOW STRONG WILL DEPEND LARGELY ON THE TRACK OF THE PARENT LOW
AND IF/WHEN/WHERE ANY SECONDARY LOWS DEVELOP. GIVEN THE COLD AIR
PUSHING IN BEHIND THE FRONT...THIS APPEARS TO BE THE TYPE OF EVENT
WHICH UNDERPERFORMS FOR THE BEACHES AND HEADLANDS BUT OVERPERFORMS
ELSEWHERE.
SNOW LEVELS WILL LOWER DRAMATICALLY IN THE COLD AIR BEHIND THE FRONT
SAT NIGHT/SUN. MEANWHILE COLD AIR ALOFT WILL KEEP THE AIR MASS
UNSTABLE WITH COOL SHOWERS AND ISOLATED THUNDERSTORMS LINGERING
THROUGH MONDAY. A FEW INCHES OF SNOW WILL LIKELY ADD UP IN THE
CASCADES BY MONDAY. SOME MODELS HINT AT THE POTENTIAL FOR YET
ANOTHER LOW TO DEVELOP TO OUR SOUTHWEST SUN NIGHT...BUT GIVEN THE
MAGNITUDE OF COLD ADVECTION BEHIND SAT EVENINGS FRONT...IT APPEARS
ANY STRONG LOW THAT WOULD DEVELOP BY THEN WOULD LIKELY STAY WELL TO
OUR SOUTH. ALL IN ALL...AN INTERESTING PATTERN FOR STORMWATCHERS THE
NEXT SEVERAL DAYS. WEAGLE
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...AN UPPER LEVEL TROUGH AND
ONSHORE FLOW WILL CONTINUE SHOWERS MONDAY NIGHT. TUESDAY MORNING
WILL BE BETWEEN SYSTEMS WITH SHOWERS RAPIDLY DECREASING UNDER BRIEF
RIDGING. THE NEXT PACIFIC FRONT WILL BRING A RETURN OF RAIN AND
MOUNTAIN SNOW TUESDAY AFTERNOON WITH SNOW LEVELS AROUND 3500 FEET.
THERE IS POTENTIAL FOR AN ATMOSPHERIC RIVER EVENT WEDNESDAY AND
THURSDAY WITH A SURFACE LOW (AND ASSOCIATED FRONT) TAPPING INTO A
SWATH OF 1.10 TO 1.4 INCHES OF PRECIPITABLE WATER. INTEGRATIVE VAPOR
TRANSPORT SHOWS THE BEST CHANCE FOR HEAVY RAIN ACROSS SW
OREGON...BUT THINK NW OREGON AND SW WASHINGTON CAN STILL GET A
DECENT SOAKING. SNOW LEVELS WILL INITIALLY START AROUND 3500 FEET
TUESDAY NIGHT...THEN RAPIDLY RISE TO AROUND 5500 FEET WEDNESDAY. TJ
&&
.AVIATION...A FRONT AND BAND OF RAIN WILL PUSH ONSHORE OVERNIGHT
AND BRING A DETERIORATION TO MVFR FLIGHT CONDITIONS TO MANY TAF
SITES BETWEEN 06Z AND 12Z MONDAY. INCREASING OFFSHORE FLOW SHOULD
TURN CONDITIONS PREDOMINANTLY VFR AREA WIDE AFTER 12Z SATURDAY.
ANOTHER LOW PRESSURE SYSTEM THAT WILL LIKELY BRING STRONGER WINDS
REGION WIDE SATURDAY EVENING WITH GUSTS UP TO 50 KT POSSIBLE ALONG
THE COAST AND 35 KT ACROSS THE INTERIOR. THIS SYSTEM WILL ALSO
LIKELY PRODUCE A PERIOD OF FLIGHT RESTRICTIONS FOR COASTAL
LOCATIONS BETWEEN 00Z AND 06Z SUNDAY.
KPDX AND APPROACHES...EXPECT PREDOMINATELY VFR CONDITIONS THROUGH
06Z SUNDAY AS A SERIES OF LOW PRESSURE SYSTEMS KEEP EAST TO SOUTH
WINDS ELEVATED. HOWEVER...A PERIOD OF STEADIER RAIN LATER TONIGHT
SHOULD BE ENOUGH TO PRODUCE A BRIEF PERIOD OF MVFR CONDITIONS...MOST
LIKELY BETWEEN 09Z AND 12Z SATURDAY. /NEUMAN
&&
.MARINE...SEVERAL SURFACE LOW PRESSURE SYSTEMS DEVELOPED THIS
AFTERNOON AND ARE MOVING NORTHEASTWARD TOWARDS THE PACIFIC
NORTHWEST. WHILE EACH STORM SYSTEM IS NOTABLE...THIS HAS LIKELY
PREVENTED A WORST CASE SCENARIO FROM UNFOLDING. NONETHELESS...GALE
FORCE WIND GUSTS ARE CURRENTLY BEING OBSERVED ACROSS THE
WATERS...AND EXPECT THESE TO CONTINUE FOR THE NEXT SEVERAL HOURS
BEFORE WEAKENING AFTER MIDNIGHT. WILL KEEP THE CURRENT STORM
WARNING GOING DUE TO AN INHERENT UNCERTAINTY WITH THIS TYPE OF
SYSTEM...BUT LATEST TRENDS IN OBSERVATIONS AND MODEL GUIDANCE ARE
NOT PROMISING.
EXPECT WINDS AND SEAS TO SUBSIDE AFTER MIDNIGHT WITH SEAS LIKELY
DROPPING INTO THE LOW TO MID TEENS SATURDAY MORNING THROUGH AT
LEAST EARLY SATURDAY AFTERNOON. HOWEVER...THE LULL IN WINDS AND
SEAS WILL BE SHORT LIVED AS THE NEXT STORM SYSTEM PRODUCES ANOTHER
SET OF STRENGTHENING SURFACE LOW PRESSURES AND STRONGER WINDS AND
HIGH SEAS ACROSS THE WATERS. THERE IS CERTAINLY POTENTIAL FOR
STORM FORCE GUSTS...BUT SUSPECT WIND GUSTS WILL GENERALLY REMAIN
IN SOLID GALE FORCE CRITERIA OF 40 TO 45 KT. AT THIS POINT...THE
STRONGEST WINDS AND ABRUPT RISE IN SEAS WILL LIKELY BEGIN ACROSS
THE CENTRAL OREGON WATERS BETWEEN 3 PM AND 6 PM AND BETWEEN 6 PM
AND 9 PM ACROSS THE NORTHERN WATERS.
WINDS AND SEAS WILL LIKELY REMAIN ELEVATED THROUGH SUNDAY WITH A
SMALL CHANCE THAT ANOTHER SURFACE LOW PRESSURE COULD IMPACT THE
REGION. HOWEVER...IT APPEARS THIS SYSTEM WILL MOST LIKELY STAY
SOUTH OF THE REGION SUNDAY AFTERNOON/EVENING.
ANOTHER FRONT TUESDAY-ISH HAS THE POTENTIAL TO BRING ANOTHER ROUND
OF GALE FORCE WINDS...WITH PERHAPS A STRONGER STORM SYSTEM
WEDNESDAY. SEAS LOOK TO REMAIN ABOVE 10 FT FOR AT LEAST THE NEXT
WEEK...AND MAY EXCEED 20 FT BY QUITE A BIT TOWARDS THE MIDDLE OF
NEXT WEEK. /NEUMAN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 4 AM PST SATURDAY FOR CENTRAL OREGON
COAST-NORTH OREGON COAST.
HIGH SURF ADVISORY UNTIL 3 AM PST SATURDAY FOR CENTRAL OREGON
COAST-NORTH OREGON COAST.
HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH LATE SATURDAY
NIGHT FOR CENTRAL OREGON COAST-NORTH OREGON COAST.
WA...HIGH WIND WARNING UNTIL 4 AM PST SATURDAY FOR SOUTH WASHINGTON
COAST.
HIGH SURF ADVISORY UNTIL 3 AM PST SATURDAY FOR SOUTH WASHINGTON
COAST.
HIGH WIND WATCH FROM SATURDAY AFTERNOON THROUGH LATE SATURDAY
NIGHT FOR SOUTH WASHINGTON COAST.
PZ...GALE WATCH FROM SATURDAY AFTERNOON THROUGH SUNDAY MORNING FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT
60 NM.
STORM WARNING UNTIL 1 AM PST SATURDAY FOR COASTAL WATERS FROM
CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.
STORM WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING
FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 PM
PST SUNDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
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 STATE COLLEGE PA
215 AM EST SAT MAR 5 2016
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL MOVE THROUGH THE REGION EARLY
TODAY...BEFORE ANOTHER WEAK CLIPPER TYPE SYSTEM BRINGS THE CHANCE
FOR MORE LIGHT RAIN OR SNOW LATER TODAY INTO SUNDAY MORNING. A
LARGE RIDGE OF HIGH PRESSURE WILL BUILD OVER THE EASTERN HALF OF
THE CONTINENT DURING THE UPCOMING WEEK. TEMPERATURES WILL SURGE
TO WELL ABOVE NORMAL LEVELS STARTING MONDAY...AND LAST THROUGH
WEDNESDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
IR LOOP AT 0630Z SHOWS EXTENSIVE STRATOCU DECK HOLDING TOUGH
ACROSS MUCH OF THE FCST AREA TO THE WEST OF THE SUSQUEHANNA`S
MAINSTEM.
MID LEVEL WARM ADVECTION WILL BRING A SHIELD OF ALTOCU/ALOTSTRATUS
ACROSS THE REGION DURING THE MID TO LATE MORNING.
EXPECT EARLY MORNING LOWS IN THE MID TO UPPER TEENS TO BE COMMON
ACROSS THE N MTNS. MORE PERSISTENT CLOUD COVER SHOULD RESULT IN
LOWS MAINLY THE L-M20S ACROSS THE REMAINDER OF CENTRAL/SOUTHERN
PA. SOME SPOTS IN SCENT PENN WILL HAVE TROUBLE SLIPPING BELOW 27F.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM SUNDAY/...
ANY EARLY SUNSHINE TODAY /MAINLY ACROSS THE SUSQ VALLEY AND POINTS
EAST OF THE STUBBORN STRATOCU DECK/ WILL FADE BEHIND THICKENING
CLOUDS BY LATE THIS MORNING...AS A CLIPPER DIVES SE FROM THE GRT
LKS.
IT WILL STAY DRY ACROSS ALL BUT THE NW MTNS THROUGH THE MIDDAY
HOURS. INVOF KBFD AND POINTS WEST...SOME FLURRIES COULD DEVELOP
AROUND 15Z...BUT THE 05Z HRRR AND PRIOR RUNS HAVE INDICATED THAT
THIS INITIAL BATCH OF VERY LIGHT QPF FIZZLES OUT ACROSS THE NW
MTNS...WITH ESSENTIALLY DRY CONDITIONS OVER THE ENTIRE REGION
THROUGH AT LEAST 20Z.
THE BULK OF THE LIGHT SNOW /WITH THE EMPHASIS ON THE WORD LIGHT/
WILL ARRIVE VERY LATE TODAY ACROSS THE WEST...AND EARLY TONIGHT
ACROSS CENTRAL AND ERN PENN WITH THE PASSAGE OF A WEAK /1016-1018
MB/ SFC LOW AND ASSOC WEAK WAA. CONSENSUS MODEL QPF IS JUST A
FEW...TO SVRL HUNDREDTHS OF AN INCH...WHICH LEADS TO SNOWFALL
AMOUNTS SIMILAR...IF NOT LIGHTER IN MOST AREAS THAN WHAT OCCURRED
ABOUT 48 HOURS PRIOR - THURSDAY NIGHT INTO FRIDAY MORNING. THE
LAURELS COULD BE THE EXCEPTION WITH THE POTENTIAL FOR AN INCH OR
TWO OF SNOW ACCUMULATION BY EARLY SUNDAY...CONSIDERING THIS AREA
WILL BE CLOSEST TO THE SFC LOW TRACK ACROSS WEST VA.
NATIONAL BLEND COMBINED WITH INPUT FROM LATEST LAMP SUPPORT MAX
TEMPS THIS AFTERNOON IN THE L30S OVR THE HIGHEST TERRAIN OF THE
ALLEGHENIES...TO ARND 40F ACROSS THE SUSQ VALLEY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE PORTION OF THE FORECAST CONTINUES TO HAVE A FAIR
AMOUNT OF AGREEMENT IN MODEL SOLUTIONS...AS A WEAK CLIPPER SLIDES
THROUGH SAT INTO EARLY SUN. STILL LOOKING AT A RELATIVELY WEAK
AND DEFINITELY MOISTURE-STARVED SYSTEM...WITH MEAN QPF SUPPORTING
A 1-2 INCH SNOWFALL WITH THE W MTNS CLIMATOLOGICALLY FAVORED FOR
THE HIGHEST AMTS. THE BEST CHANCES FOR PRECIP FROM MDL TIMING OF
WEAK SFC REFLECTION SUGGEST THE STEADIEST SNOW SHOULD FALL SAT
NIGHT.
SOME BRIEFLY MDT SNOW RATES ARE POSSIBLE FROM THE LAURELS...INTO
SOUTH CENTRAL PENN SATURDAY NIGHT AS SOME FLEETING BANDS OF MID
LEVEL FRONTOGENESIS DEVELOP/DRIFT ESE. HOWEVER...MOST OF THE SNOW
WILL BE VERY LIGHT /SIMILAR TO THU NIGHT AND EARLY FRIDAY/ AS THE
FAVORABLE THERMAL RIBBON FOR DENDRITIC SNOW GROWTH STAYS BETWEEN
7-11 KFT AGL AND WEAK OMEGA COINCIDES WITH IT. THE BEST PERIOD
FOR A LIGHT SNOW ACCUMULATION OF AROUND AN INCH OR SO WILL BE IN
THE 06-12Z SUNDAY PERIOD.
BRIGHTENING SKIES BUT STILL CHILLY WX ANTICIPATED SUNDAY...AS HIGH
PRES BUILDS IN FROM THE WEST WITH LIGHT NW FLOW. WIDE CONSENSUS
AMONG MED RANGE GUIDANCE IN A MARKED WARM UP NEXT WEEK...AS
ANOMALOUS UPPER LVL RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND
ASSOC SW FLOW OVR PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER
12Z ECENS. TEMPS WILL TAKE A RUN AT 70F BY WED OVR SOUTHERN PA.
MODELS ARE IN BETTER AGREEMENT ON BRINGING A QUASI-STATIONARY
FRONTAL BOUNDARY RUNNING FROM THE MISS VALLEY THRU THE GRT LKS AT
INTERFACE OF E COAST RIDGE AND PLAINS TROF THROUGH PA BY
MIDWEEK...AS HIGH PRESSURE TRACKING EASTWARD ACROSS CANADA WILL
NUDGE THE FRONT SOUTHWARD AND PIVOT IT FROM MORE OF A N-S
ORIENTATION TO A W-E DIRECTION. THIS COULD BRING THE NEXT BEST
CHANCE FOR PRECIPITATION AS WEAK WAVES COULD RIPPLE TOWARD PA
ALONG THE PORTION OF THE /WARM/ FRONT OVER THE OHIO VALLEY. GIVEN
THE STRONG WAA IT LOOKS TO BE ALL RAIN...WITH PRECIP BRACKETED
BETWEEN LATE IN THE DAY WED AND FRI. THE GFS IS MORE AGGRESSIVE
WITH ONSET OF PRECIP AND QPF AMOUNTS THAN THE ECMWF...BUT EITHER
WAY IT LOOKS TO BE A SHOWERY END TO THE WEEK AND TEMPS GRADUALLY
COOL BACK DOWN BUT REMAIN ABOVE NORMAL.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
FOR THE 05/06Z TAFS THROUGH 06/06Z
ISSUED AT 135 AM EST SAT MAR 5 2016
LOW CLOUDS TRAPPED UNDERNEATH SUBSIDENCE INVERSION WILL KEEP MVFR
TO LOW VFR CIGS /1.5-4KFT AGL/ IN PLACE THIS MORNING ACROSS THE
WRN 2/3 OF THE AIRSPACE. VFR ALONG/EAST OF IPT-MDT LINE WITH FEW-
SCT CIGS AT 5KFT. LOW PRESSURE TRACKING SOUTHEAST FROM WI THRU WV
WILL BRING LIGHT SNOW AND REDUCED CONDITIONS LATER THIS AFTERNOON
INTO TONIGHT. HIGHEST CONFIDENCE IN IFR IS AT JST.
OUTLOOK...SUNDAY-WEDNESDAY
SUN...MVFR CIGS WEST BECOMING VFR. NO SIG WX.
MON-TUE...VFR/NO SIG WX.
WED...VFR. RAIN POSSIBLE NORTHWEST AIRSPACE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT/FITZGERALD
LONG TERM...RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
248 AM EST SAT MAR 5 2016
.SHORT TERM (TODAY AND TONIGHT)...
CURRENT WATER VAPOR IMAGERY AND RAP UPPER AIR ANALYSIS INDICATES A
TROUGH ACROSS THE NORTHERN MISSISSIPPI RIVER VALLEY WITH
NORTHWESTERLY FLOW ACROSS THE FORECAST AREA. THIS TROUGH WILL BE THE
MAIN FEATURE FOR THE SHORT-TERM FORECAST. AT THE SURFACE... HIGH
PRESSURE IS IN PLACE WITH CALM WINDS AND MOSTLY CLEAR SKIES. DUE TO
THIS RADIATIONAL COOLING...COULD SEE SOME AREAS OF PATCHY FOG THIS
MORNING BUT NOT EXPECTING ANYTHING WIDESPREAD OR DENSE ENOUGH TO
ISSUE AN ADVISORY. ANY SHALLOW FOG THAT DOES FORM WILL MIX OUT
QUICKLY THIS MORNING WITH MOSTLY SUNNY SKIES EXPECTED THROUGHOUT
MUCH OF THE MORNING. FURTHER TO THE WEST...A SURFACE LOW CAN BE
NOTED ACROSS THE UPPER MISSISSIPPI RIVER VALLEY WITH A COLD FRONT
EXTENDING SOUTHWESTWARD INTO THE SOUTHERN PLAINS. THE AFOREMENTIONED
TROUGH WILL DIVE SOUTHEASTWARD INTO THE OHIO RIVER VALLEY WITH
CLOUDS INCREASING ACROSS THE NORTHERN COUNTIES LATE IN THE MORNING.
PW VALUES ARE A BIT MORE IMPRESSIVE THAN IN PREVIOUS MODEL RUNS WITH
VALUES IN THE 0.5-0.6 INCH RANGE. THESE VALUES ARE RIGHT AROUND TO
JUST ABOVE AVERAGE FOR EARLY MARCH. MODEL SOUNDINGS SUPPORT ENOUGH
SATURATION FOR LIGHT PRECIPITATION TO DEVELOP THIS AFTERNOON WITH THE
NORTHERN HALF OF THE AREA HAVING THE HIGHEST CHANCES. THE COLD FRONT
WILL MOVE THROUGH THE AREA BETWEEN 00-06Z WITH COLDER AIR IN THE LOW
LEVELS MOVING IN BEHIND THE FRONT. LATEST MODEL GUIDANCE SUGGEST
ENOUGH MOISTURE LEFT OVER FOR A FEW SNOW SHOWERS/FLURRIES FOR
ELEVATIONS ABOVE 3 KFT LATE TONIGHT. HOWEVER...THE MOISTURE IS
LIMITED AND DO NOT EXPECT ANY ACCUMULATIONS WOULD APPROACH ADVISORY
LEVEL CRITERIA.
.LONG TERM (SUNDAY THROUGH FRIDAY)...
STRONG RIDGE BUILDS IN ACROSS THE SOUTHERN APPALACHIAN REGION
EARLY IN THE EXTENDED. THIS WILL USHER IN DRY...WARM CONDITIONS. A
STRONG WARMING TREND SUNDAY AND MONDAY WILL CULMINATE WITH
TEMPERATURES REACHING INTO THE UPPER 60S AND 70S TUESDAY AND
WEDNESDAY. THE RIDGE SHIFTS EAST OF THE REGION THURSDAY AND
FRIDAY...ALLOWING A SYSTEM THAT HAS BEEN STALLED OVER THE WEST TN
AREA TO MOVE IN. MODELS IN POOR AGREEMENT ON DETAILS BY THE END OF
THE PERIOD....BUT WEDNESDAY NIGHT INTO THURSDAY...CLOUDS WILL
INCREASE AND SCATTERED RAIN SHOWERS WILL MOVE IN. AS THE BOUNDARY
AND UPPER TROUGH MOVE THROUGH AROUND FRIDAY TIME FRAME...THE
SHOWERS WILL BECOME WIDESPREAD AND COULD SEE ISOLATED THUNDERSTORMS
DEVELOP BY THE END OF THE PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 62 35 63 41 / 10 0 0 0
KNOXVILLE MCGHEE TYSON AIRPORT, TN 55 35 56 37 / 20 30 0 0
OAK RIDGE, TN 56 35 56 37 / 30 30 0 0
TRI CITIES AIRPORT, TN 51 33 53 33 / 60 60 0 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
MA/MJB
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
544 AM PST SAT MAR 5 2016
...HEAVY RAIN LATER THIS AFTERNOON AND EVENING...
...MODERATE RAIN EVENT SUNDAY NIGHT WITH NEXT FRONT...
.SYNOPSIS...PERIODS OF RAIN...MAINLY LIGHT THIS MORNING. RAIN WILL
THEN INCREASE AND BECOME MODERATE TO HEAVY AFTER 2 PM AS A STRONG
COLD FRONT APPROACHES THE BAY AREA. PERIODS OF HEAVY RAIN THIS
EVENING WITH GUSTY SOUTHERLY WINDS. WIND AND RAIN WILL RAPIDLY
WIND DOWN BEFORE MIDNIGHT. SHOWERS AND ISOLATED THUNDERSTORMS
SUNDAY IN POST FRONTAL ENVIRONMENT. NEXT FRONT ARRIVES SUNDAY
NIGHT WITH ANOTHER ROUND OF MODERATE RAINS. SHOWERS LINGER MONDAY
THEN DRY THROUGH MIDWEEK. CHANCE OF NORTH BAY RAIN BY WEDNESDAY
THEN ALL OF THE BAY AREA AND CENTRAL COAST BY THURSDAY AND FRIDAY.
&&
.DISCUSSION...AS OF 4:04 AM PST SATURDAY...ISSUED A PNS AT 3 AM
WITH LATEST 24 HOUR RAINFALL TOTALS. RADAR SHOWS OVERNIGHT STEADY
RAINFALL MOVING EASTWARD BUT MORE RETURNS STARTING TO DEVELOP WELL
OFFSHORE. WERE STILL IN THE WARM ADVECTION ENVIRONMENT WITH MAINLY
LIGHT AND PERIODIC RAINFALL THROUGH LUNCH TIME TODAY. IR SATELLITE
OVER THE LAST 6 HOURS OR SO IS SHOWING A BAROCLINIC LEAF CLOUD
BLOWING UP OUT NEAR 130W/36N...EVIDENCE OF STRONG INCOMING JET
STREAK AND STRENGTHENING SURFACE COLD FRONTAL BOUNDARY. THIS IS
THE FEATURE THE MODELS HAVE BEEN HONING IN ON NOW FOR NEARLY THE
LAST WEEK. FEATURE WILL QUICKLY APPROACH THE COAST TODAY AND
EXPECT MODERATE RAINS TO START IN EARNEST AROUND 2 PM OR SO OVER
MUCH OF THE GREATER BAY AREA. LOCAL HILLS SUCH AS BIG SUR AND
SANTA CRUZ MOUNTAINS WILL SEE PERIODS OF RAIN THROUGH MOST OF THE
DAY.
ANYWAY THE HIGHLY ANTICIPATED FRONTAL PASSAGE SHOULD BE OBVIOUS
FROM ROUGHLY 3 PM TO 8 PM LOCAL TIME WHEN VERY STRONG WINDS AND
HEAVY RAIN OCCUR OVER A SEVERAL HOUR WINDOW OF TIME. DO EXPECT
SOME PREFRONTAL SOUTHERLY WIND GUSTS TO SHOW UP AS EARLY AS LUNCH
TIME AND CURRENT TIMING OF WIND ADVISORY TO START THEN STILL LOOKS
GOOD. SANTA CRUZ MOUNTAINS OFTEN SEE WIND DAMAGE AND LINES DOWN IN
THESE TYPE OF PATTERNS AS SYNOPTIC FLOW AND STRONG SOUTHEAST WINDS
FLOWING OUT OF SALINAS VALLEY FOCUS UP THERE. ANYWAY THE HRRR AND
RAP SHORT TERM MESOSCALE MODELS ARE IN AGREEMENT THAT THE HEAVIEST
RAINS FALL FROM ROUGHLY 4 TO 8 PM THIS EVENING (EARLIEST IN THE
NORTH BAY AND LATEST IN MONTEREY BAY REGION). STORM TOTALS FROM
NOW THROUGH ABOUT 10 PM TONIGHT SHOULD BRING 1-2 INCHES TO THE
LOWER ELEVATIONS WITH 2-5 INCHES FOR THE NORTH BAY/SANTA CRUZ AND
SANTA LUCIA HILLS. (USUAL DRY SPOTS IN THE SALINAS AND EAST BAY
VALLEYS WILL BE UNDER AN INCH). THIS STORM WILL CAUSE ISSUES
TONIGHT THROUGHOUT THE BAY AREA WITH TRAFFIC...LOCALIZED FLOODING
DUE TO THE HEAVY RAIN RATES OVER A SHORT WINDOW OF TIME AND
ASSOCIATED WIND DAMAGE ISSUES.
A DISTINCT LULL IN THE ACTION WILL OCCUR AFTER MIDNIGHT BEHIND THE
FRONT WITH ONLY SOME LINGERING SHOWERS AND MUCH LIGHTER SW WINDS.
SHOWER AND POST FRONTAL T-STORMS POSSIBLE ON SUNDAY BUT PARTLY
CLOUDY SKIES WILL PREVAIL FOR MANY AREAS SOUTH OF SAN FRANCISCO ON
SUNDAY. NEXT SYSTEM APPROACHING WILL BRING GENTLE WARM ADVECTION
RAINS TO THE NORTH BAY BY SUNDAY AFTERNOON.
THEN ON SUNDAY NIGHT POTENT SHORTWAVE WITH MUCH COLDER AIR ALOFT
WILL PASS FROM NW TO SE ACROSS THE DISTRICT. ANOTHER ROUND OF SOME
HEAVY RAIN SHOWERS WITH POSSIBLE T-STORMS WILL OCCUR. RAIN TOTALS
WILL BE LESS WITH THIS SYSTEM BUT SOME LOCALIZED HEAVY RAINFALL
SHOULD BE EXPECTED. LOOKS LIKE THE BULK OF THE HEAVY RAIN IS DONE
BY 12Z MONDAY WITH ONLY SOME LINGERING RAINS SHOWERS BY 15Z MONDAY
FOR THE MORNING COMMUTE. HOWEVER EVEN A WET START TO THE COMMUTE
IS OFTEN ENOUGH TO THROW THINGS INTO DISARRAY TO START OUT THE
WORK WEEK. SIMILAR TO SUNDAY...SHOWERS CHANCES WILL LINGER MONDAY
BUT BE ON THE DECREASE THROUGH THE DAY.
LOOKS DRY MONDAY NIGHT AND TUESDAY. LATEST ECMWF HAS TRENDED
WETTER BY WEDS FOR THE NORTH BAY WITH SOME WARM FRONTAL LIGHT RAIN
CHANCES. MORE ORGANIZED COLD FRONT THEN ARRIVES LATER THURSDAY
INTO FRIDAY. WILL HONE IN ON THOSE DETAILS AFTER WE GET THROUGH
THE WEEKEND SYSTEMS BUT THE STORMS LATER NEXT WEEK LOOK MODERATE
IN STRENGTH/INTENSITY.
&&
.AVIATION...AS OF 5:44 AM PST SATURDAY...A STRONG COLD FRONT WILL
SWEEP EAST OVER THE AREA THIS EVENING. THIS FRONTAL PASSAGE HAS
THE POTENTIAL TO BE THE STRONGEST WE`VE SEEN THIS WINTER SEASON.
DETERIORATING WX CONDITIONS TODAY WITH MODERATE-HEAVY RAIN AND
HEAVY S-SE WIND COMBINED UP TO THE FRONTAL PASSAGE THIS EVENING.
WORTH NOTING PRE-FRONTAL S-SE WINDS OFTEN CAUSES A RAIN SHADOW FOR
PLACES LIKE THE SOUTH BAY AND THE MONTEREY PENINSULA THUS THE RAIN
MAY AT TIMES BECOME MORE PERIODIC TODAY IN PLACES THAT ARE IN THE
LEE OF HIGHER TERRAIN. SHOWERY COLDER MORE UNSTABLE AIR ARRIVES
LATE TONIGHT AND SUNDAY.
VICINITY OF KSFO...AIRPORT WEATHER WARNING ISSUED FOR STRONG AND
GUSTY S-SE WINDS. MVFR CIGS. RAIN.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS. STRONG AND GUSTY SOUTHERLY
WINDS DEVELOPING TODAY. RAIN.
&&
.BEACHES...AS OF 5:30 AM PST SATURDAY...A HIGH SURF ADVISORY
BEGINS 10 PM TONIGHT AND LASTS INTO TUESDAY MORNING. WESTERLY
SWELL WILL BE PEAKING CLOSE TO 20 FEET WITH 14 SECOND SWELL
PERIODS FROM LATE SUNDAY NIGHT TO MONDAY NIGHT. IF FUTURE WAVE
MODEL FORECASTS TREND STEADY OR HIGHER WITH THE PEAK OF THIS SWELL
TRAIN THEN THE ADVISORY MAY NEED TO BE UPGRADED TO A HIGH SURF
WARNING AT A LATER POINT IN TIME. PLEASE STAY TUNED.
&&
.MARINE...AS OF 3:43 AM PST SATURDAY...SOUTHERLY WINDS WILL BECOME
STRONG AND GUSTY TODAY AS A COLD FRONT OVER THE EASTERN PACIFIC
ADVANCES EAST OVER THE AREA THIS EVENING. GALE FORCE WINDS ARE
EXPECTED OVER THE WATERS THIS AFTERNOON AND TONIGHT. COLD UNSTABLE
AIR WILL SETTLE OVER THE AREA BRINGING A SLIGHT CHANCE OF
THUNDERSTORMS ON SUNDAY. ANOTHER VIGOROUS FRONTAL SYSTEM WILL
ADVANCE OVER THE AREA SUNDAY NIGHT AND EARLY MONDAY MORNING. A
LARGE WESTERLY SWELL WILL ARRIVE TONIGHT AND PERSIST THROUGH EARLY
TUESDAY MORNING.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...WIND ADVISORY...SF BAY AREA FROM NOON TO 11 PM SAT
WIND ADVISORY...MRY BAY AREA FROM 1 PM SAT TO 1 AM SUNDAY
SCA...MRY BAY FROM 10 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 10 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 10 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 10 AM
GLW...MRY BAY FROM 4 PM
GLW...PIGEON PT TO PT PINOS 0-10 NM FROM 4 PM
GLW...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 4 PM
GLW...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 4 PM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 10 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 10 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 10 AM
GLW...PT ARENA TO PT REYES 0-10 NM FROM 10 AM
GLW...PT REYES TO PIGEON PT 0-10 NM FROM 10 AM
GLW...PT ARENA TO PIGEON PT 10-60 NM FROM 10 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR
SCA...SF BAY UNTIL NOON
GLW...SF BAY FROM NOON
&&
$$
PUBLIC FORECAST: R_WALBRUN
AVIATION/MARINE: CANEPA
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
404 AM PST SAT MAR 5 2016
...HEAVY RAIN LATER THIS AFTERNOON AND EVENING...
...MODERATE RAIN EVENT SUNDAY NIGHT WITH NEXT FRONT...
.SYNOPSIS...PERIODS OF RAIN...MAINLY LIGHT THIS MORNING. RAIN WILL
THEN INCREASE AND BECOME MODERATE TO HEAVY AFTER 2 PM AS A STRONG
COLD FRONT APPROACHES THE BAY AREA. PERIODS OF HEAVY RAIN THIS
EVENING WITH GUSTY SOUTHERLY WINDS. WIND AND RAIN WILL RAPIDLY
WIND DOWN BEFORE MIDNIGHT. SHOWERS AND ISOLATED THUNDERSTORMS
SUNDAY IN POST FRONTAL ENVIRONMENT. NEXT FRONT ARRIVES SUNDAY
NIGHT WITH ANOTHER ROUND OF MODERATE RAINS. SHOWERS LINGER MONDAY
THEN DRY THROUGH MIDWEEK. CHANCE OF NORTH BAY RAIN BY WEDNESDAY
THEN ALL OF THE BAY AREA AND CENTRAL COAST BY THURSDAY AND FRIDAY.
&&
.DISCUSSION...AS OF 4:04 AM PST SATURDAY...ISSUED A PNS AT 3 AM
WITH LATEST 24 HOUR RAINFALL TOTALS. RADAR SHOWS OVERNIGHT STEADY
RAINFALL MOVING EASTWARD BUT MORE RETURNS STARTING TO DEVELOP WELL
OFFSHORE. WERE STILL IN THE WARM ADVECTION ENVIRONMENT WITH MAINLY
LIGHT AND PERIODIC RAINFALL THROUGH LUNCH TIME TODAY. IR SATELLITE
OVER THE LAST 6 HOURS OR SO IS SHOWING A BAROCLINIC LEAF CLOUD
BLOWING UP OUT NEAR 130W/36N...EVIDENCE OF STRONG INCOMING JET
STREAK AND STRENGTHENING SURFACE COLD FRONTAL BOUNDARY. THIS IS
THE FEATURE THE MODELS HAVE BEEN HONING IN ON NOW FOR NEARLY THE
LAST WEEK. FEATURE WILL QUICKLY APPROACH THE COAST TODAY AND
EXPECT MODERATE RAINS TO START IN EARNEST AROUND 2 PM OR SO OVER
MUCH OF THE GREATER BAY AREA. LOCAL HILLS SUCH AS BIG SUR AND
SANTA CRUZ MOUNTAINS WILL SEE PERIODS OF RAIN THROUGH MOST OF THE
DAY.
ANYWAY THE HIGHLY ANTICIPATED FRONTAL PASSAGE SHOULD BE OBVIOUS
FROM ROUGHLY 3 PM TO 8 PM LOCAL TIME WHEN VERY STRONG WINDS AND
HEAVY RAIN OCCUR OVER A SEVERAL HOUR WINDOW OF TIME. DO EXPECT
SOME PREFRONTAL SOUTHERLY WIND GUSTS TO SHOW UP AS EARLY AS LUNCH
TIME AND CURRENT TIMING OF WIND ADVISORY TO START THEN STILL LOOKS
GOOD. SANTA CRUZ MOUNTAINS OFTEN SEE WIND DAMAGE AND LINES DOWN IN
THESE TYPE OF PATTERNS AS SYNOPTIC FLOW AND STRONG SOUTHEAST WINDS
FLOWING OUT OF SALINAS VALLEY FOCUS UP THERE. ANYWAY THE HRRR AND
RAP SHORT TERM MESOSCALE MODELS ARE IN AGREEMENT THAT THE HEAVIEST
RAINS FALL FROM ROUGHLY 4 TO 8 PM THIS EVENING (EARLIEST IN THE
NORTH BAY AND LATEST IN MONTEREY BAY REGION). STORM TOTALS FROM
NOW THROUGH ABOUT 10 PM TONIGHT SHOULD BRING 1-2 INCHES TO THE
LOWER ELEVATIONS WITH 2-5 INCHES FOR THE NORTH BAY/SANTA CRUZ AND
SANTA LUCIA HILLS. (USUAL DRY SPOTS IN THE SALINAS AND EAST BAY
VALLEYS WILL BE UNDER AN INCH). THIS STORM WILL CAUSE ISSUES
TONIGHT THROUGHOUT THE BAY AREA WITH TRAFFIC...LOCALIZED FLOODING
DUE TO THE HEAVY RAIN RATES OVER A SHORT WINDOW OF TIME AND
ASSOCIATED WIND DAMAGE ISSUES.
A DISTINCT LULL IN THE ACTION WILL OCCUR AFTER MIDNIGHT BEHIND THE
FRONT WITH ONLY SOME LINGERING SHOWERS AND MUCH LIGHTER SW WINDS.
SHOWER AND POST FRONTAL T-STORMS POSSIBLE ON SUNDAY BUT PARTLY
CLOUDY SKIES WILL PREVAIL FOR MANY AREAS SOUTH OF SAN FRANCISCO ON
SUNDAY. NEXT SYSTEM APPROACHING WILL BRING GENTLE WARM ADVECTION
RAINS TO THE NORTH BAY BY SUNDAY AFTERNOON.
THEN ON SUNDAY NIGHT POTENT SHORTWAVE WITH MUCH COLDER AIR ALOFT
WILL PASS FROM NW TO SE ACROSS THE DISTRICT. ANOTHER ROUND OF SOME
HEAVY RAIN SHOWERS WITH POSSIBLE T-STORMS WILL OCCUR. RAIN TOTALS
WILL BE LESS WITH THIS SYSTEM BUT SOME LOCALIZED HEAVY RAINFALL
SHOULD BE EXPECTED. LOOKS LIKE THE BULK OF THE HEAVY RAIN IS DONE
BY 12Z MONDAY WITH ONLY SOME LINGERING RAINS SHOWERS BY 15Z MONDAY
FOR THE MORNING COMMUTE. HOWEVER EVEN A WET START TO THE COMMUTE
IS OFTEN ENOUGH TO THROW THINGS INTO DISARRAY TO START OUT THE
WORK WEEK. SIMILAR TO SUNDAY...SHOWERS CHANCES WILL LINGER MONDAY
BUT BE ON THE DECREASE THROUGH THE DAY.
LOOKS DRY MONDAY NIGHT AND TUESDAY. LATEST ECMWF HAS TRENDED
WETTER BY WEDS FOR THE NORTH BAY WITH SOME WARM FRONTAL LIGHT RAIN
CHANCES. MORE ORGANIZED COLD FRONT THEN ARRIVES LATER THURSDAY
INTO FRIDAY. WILL HONE IN ON THOSE DETAILS AFTER WE GET THROUGH
THE WEEKEND SYSTEMS BUT THE STORMS LATER NEXT WEEK LOOK MODERATE
IN STRENGTH/INTENSITY.
&&
.AVIATION...AS OF 10:30 PM PST FRIDAY...RADAR INDICATES SHOWERS
MOVING OVER THE AREA FROM THE SOUTHWEST. THIS WILL KEEP PERIODS
OF LIGHT RAIN GOING THROUGH SATURDAY MORNING WHEN THINGS WILL RAMP
UP IN TERMS OF WINDS AND RAIN. CIGS WILL BE BOUNCING UP AND DOWN
BUT WILL REMAIN PREDOMINANTLY IN THE MVFR RANGE. SOUTH TO
SOUTHEAST WINDS INCREASE AFTER 16Z WITH SURFACE WINDS GUSTING TO
25 KT AND INCREASE EVEN MORE TO 30-35 KT AFTER 21Z. WIND SHEAR
MAY BE A FACTOR SATURDAY AFTERNOON AS 925 MB WINDS ARE SOUTHWEST
50 KT.
VICINITY OF KSFO...MVFR CIGS. BASES MAINLY 2500 FEET LOWERING TO
1000-1500 FEET AFTER 16Z. RAIN SHOWERS TONIGHT WILL BECOME STEADY
MODERATE RAIN SATURDAY MORNING. SOUTHERLY WINDS AROUND 15 KT
INCREASING TO 20-25 KT WITH GUSTS TO 30 KT AFTER 16Z. WINDS
FURTHER INCREASING AS FRONT MOVES IN AND WILL LIKELY REACH
AIRPORT WEATHER WARNING CRITERIA.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS WITH RAIN SHOWERS.
STEADIER RAIN RETURNING BY SATURDAY AFTERNOON WITH INCREASING
SOUTHERLY WINDS.
&&
.BEACHES...AS OF 10:30 PM PST FRIDAY...LARGE SWELLS WILL ARRIVE
ALONG THE COAST BY MONDAY. SWELL HEIGHTS MAY REACH 15 TO 20 FEET
WITH SWELL PERIOD OF 14 SECONDS. WEST FACING BEACHES WILL FEEL
THE BRUNT OF THIS SWELL TRAIN... WITH STRONG RIP CURRENTS... LARGE
SHORE BREAK... AND SNEAKER WAVES POSSIBLE. A COMBINATION OF HIGH
SURF... MODERATE TO HEAVY RAIN... AND HIGH TIDE MAY ALSO LEAD TO
COASTAL FLOODING OVER THE UPCOMING DAYS. REMEMBER... NEVER
UNDERESTIMATE THE OVERWHELMING POWER OF THE OCEAN... SEVERAL
INDIVIDUALS HAVE BEEN SWEPT OUT TO SEA THIS SEASON.
&&
.MARINE...AS OF 03:26 AM PST SATURDAY... A POWERFUL STORM WILL
BRING RAIN AND STRONG WINDS TO THE AREA SATURDAY. GALE FORCE WINDS
ARE EXPECTED OVER THE WATERS SATURDAY AFTERNOON AND NIGHT. WINDS
WILL DECREASE EARLY SUNDAY AFTER THE STORM MOVES THROUGH BUT COLD
UNSTABLE AIRMASS WILL SETTLE OVER THE AREA BRINGING A SLIGHT
CHANCE OF THUNDERSTORMS ON SUNDAY. A LARGE MODERATE TO LONG PERIOD
WEST SWELL WILL BEGIN TO ARRIVE AND PERSIST THROUGH EARLY NEXT
WEEK. THE LARGEST SWELL ARRIVES MONDAY.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...WIND ADVISORY...SF BAY AREA FROM NOON TO 11 PM SAT
WIND ADVISORY...MRY BAY AREA FROM 1 PM SAT TO 1 AM SUNDAY
SCA...MRY BAY FROM 10 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 10 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 10 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 10 AM
GLW...MRY BAY FROM 4 PM
GLW...PIGEON PT TO PT PINOS 0-10 NM FROM 4 PM
GLW...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 4 PM
GLW...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 4 PM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 10 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 10 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 10 AM
GLW...PT ARENA TO PT REYES 0-10 NM FROM 10 AM
GLW...PT REYES TO PIGEON PT 0-10 NM FROM 10 AM
GLW...PT ARENA TO PIGEON PT 10-60 NM FROM 10 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR
SCA...SF BAY UNTIL NOON
GLW...SF BAY FROM NOON
&&
$$
PUBLIC FORECAST: R_WALBRUN
AVIATION: CANEPA
MARINE: CANEPA
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
603 AM CST SAT MAR 5 2016
.SHORT TERM...(Today)
ISSUED AT 241 AM CST SAT MAR 5 2016
Patchy fog will affect central Illinois ahead of an advancing
cold front early this morning. The fog will clear by mid-morning as
cold front departs into Indiana by 11 am. Little to no precipitation
is expected with the frontal passage in central Illinois, except for
possibly a few sprinkles in areas northeast of Champaign to
Danville. Winds will shift from southwest to northwest behind the
front, and become breezy with gusts to 25 mph at times later this
morning and this afternoon.
The latest HRRR and RAP guidance are pointing towards enough
residual low level moisture behind the front for mostly cloudy skies
to linger through at least mid-afternoon. Breaks will eventually
develop in the cloud layer due to turbulent mixing of dry mid-level
air toward the surface. Areas southwest of Springfield to Mattoon
will have the best chances of seeing sunshine earlier, but even
northeast areas should see sunshine break through later this
afternoon. Even limited late afternoon sunshine should help high
temperatures reach the mid 40s north of I-74, with lower 50s for
areas from Jacksonville to Effingham to Lawrenceville.
.LONG TERM...(Tonight through Friday)
ISSUED AT 241 AM CST SAT MAR 5 2016
Mild and wet period shaping up for much of the upcoming week, as
upper flow finally trends more toward the southwest. Main issue will
be with the rains, as a frontal boundary will be draped over the
state part of the time, and will limit some of the rainfall north of
it around midweek.
High pressure will quickly pass through the Midwest tonight, and
southerly winds will be in place by Sunday morning and become a bit
gusty. This will bring temperatures well into the 50s, with some 60
degree readings possible over the southwest CWA. Some WAA-type
precip expected to develop by afternoon west of the Illinois border,
but forecast soundings in our area quite parched below 700 mb until
evening, and thus will keep the daytime hours dry albeit with
increasing clouds. Have limited mentionable PoP`s Sunday night to
west of I-55, with most of the energy tracking into northwest
Illinois.
On Monday, southerly winds expected to gust from 25-30 mph, pushing
temperatures well into the 60s. During this time, an upper trough
will be digging southward along the California coast, closing off a
low over the Baja. Nice moisture surge coming northward from the
Gulf of Mexico will combine with a wave/front in the northern stream
to gradually increase rain chances from west to east across the
state. Reasonable agreement among the models through about Tuesday
evening with the cold front being just to our northwest. Waves of
low pressure will surge northeast along the front bringing periods
of heavier rain, but how far south the front makes it first will be
key. The ECMWF is slowest in exiting the rain (not until Thursday
evening over the southeast CWA), while the GFS and Canadian show
periodic surges of rain until Thursday morning. Went with
categorical PoP`s (80%) for most areas east of I-55 Tuesday night
through Wednesday night. WPC progs and blended model guidance
suggesting potential for 3-4 inches of rain through the week in this
area, subject to the oscillations of the front. Hydrologic Outlook
product is being used to address this heavy rain concern for the
time being.
The upper low will only slowly drift through northern Mexico, cut
off from the northern flow through much of the week. Late in the
period, the GFS and ECMWF show this low finally ejecting northeast,
although the GFS is much faster in bringing the frontal boundary
back north. With the front position still a significant question,
PoP`s generally remain in place over most of the forecast area into
Friday. Temperatures north of the front will cool a bit mid week,
but still be mid-upper 50s for highs.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 600 AM CST SAT MAR 5 2016
A cold front, currently passing on a line from Galesburg to
Quincy, will continue to track east across our area this morning.
Forecast soundings and last few runs of the HRRR model correctly
depicted the IFR/LIFR ceilings in over our eastern terminals of
CMI, BMI, and DEC. PIA also dropped down to VLIFR vis and IFR cig.
Conditions will improve to VFR at all the terminal sites as the
cold front passes between 13z and 16z.
Satellite images show a region of high MVFR and VFR clouds
rotating into NW IL. They are poised to affect all of our terminal
sites later this morning and early this afternoon, with less
coverage for the southern TAF sites of SPI and DEC. Turbulent
mixing of dry mid level air should help to create breaks in cloud
cover as the afternoon progresses.
The winds are the other issue today, with southwest winds becoming
light as the cold front passes, then increasing out of the
northwest shortly after FROPA. Sustained winds will become 12-16kt
with gusts to 23kt at times late this morning and early this
afternoon. Pressure rises will weaken later this afternoon, with
gusts diminishing by sunset.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...Geelhart
AVIATION...Shimon
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
955 AM EST SAT MAR 5 2016
.UPDATE...
ISSUED AT 955 AM EST SAT MAR 5 2016
14Z SFC ANALYSIS SHOWS LOW PRESSURE DIVING SOUTHEAST THROUGH THE
GREAT LAKES WITH A WEAK COLD FRONT PASSING THE MID MISSISSIPPI
VALLEY. HERE TO THE EAST...A MID LEVEL DISTURBANCE IS DEPARTING
THE CENTRAL APPALACHIANS. THIS IS RESULTING IN SOME LIGHT PCPN
DROPPING THROUGH EAST KENTUCKY THIS MORNING. IN ADDITION TO THE
SPRINKLES AND LIGHT RAIN...AREAS OF FOG...LOCALLY DENSE...PLAGUED
THE HIGHER ELEVATIONS THROUGH EAST KENTUCKY EARLY THIS MORNING.
THE FOG IS STARTING TO DISSIPATE WITH IMPROVING VISIBILITY AND
LIFTING CEILINGS. HOWEVER...THE LOW CLOUDS AND PCPN ARE RETARDING
A TEMPERATURE RISE SO FAR THIS MORNING WITH MOST PLACES STILL IN
THE LOW 30S. THE APPROACH OF THE WEAKENING LOW AND ITS FRONT
SHOULD MIX OUT THE LOWER CLOUDS BY MIDDAY WITH WARMING
TEMPERATURES THE RESULT...THOUGH ANOTHER ROUND MORE SUBSTANTIVE
SHOWERS WILL LIKELY DEVELOP AND CROSS EAST KENTUCKY THIS
AFTERNOON. HAVE ADJUSTED THE FORECAST TO SLOW THE TEMP RISE THIS
MORNING AND TO FINE TUNE THE POPS/WX THROUGH THE AFTERNOON PER THE
LATEST HRRR AND NAM12. DID ALSO TWEAK THE DEWPOINTS...CURRENTLY
REPORTING SIMILAR VALUES TO DRY TEMPS AT MOST SITES...PER THE
LATEST OBS AND TRENDS. LIGHT WINDS EARLY THIS MORNING WILL SHIFT
TO THE SOUTHWEST AND PICK UP TO NEAR 10 MPH THIS AFTERNOON ALSO
HELPING TEMPS TO REBOUND INTO THE 40S. THE GRID UPDATES HAVE BEEN
SENT TO THE NDFD AND WEB SERVERS...WITH A FRESHENED SET OF ZONES
AND HWO ALSO ISSUED.
UPDATE ISSUED AT 656 AM EST SAT MAR 5 2016
CURRENT RADAR IS SHOWING A LINE OF PRECIPITATION MOVING ACROSS THE
NORTHERN PORTION OF THE CWA. ACCORDING TO THE LATEST
OBSERVATIONS...PRECIP IS LIKELY STILL NOT HITTING THE
GROUND...WITH ONLY ONE BRIEF OBSERVATION OF LIGHT SNOW IN THE
CINCINNATI AREA UNDER A HIGHER RETURN OVER THE LAST HOUR. IT IS
POSSIBLE THAT SOME FLURRIES ARE OCCURRING OUT OF THIS GIVEN
TEMPERATURES AT OR NEAR THE FREEZING MARK...BUT NOTHING IS
EXPECTED TO ACCUMULATE. OVER THE NEXT HOUR...EXPECT RETURNS TO
INTENSIFY AND PRECIP TO BEGIN HITTING THE GROUND...BUT NOT BEFORE
TEMPERATURES BEGIN A WARMING TREND ABOVE FREEZING AND PRECIP
CHANGES TO MAINLY RAIN.
MEANWHILE...STILL SEEING QUITE A BIT OF FOG ACROSS THE REMAINDER
OF THE CWA...THOUGH THERE HAS BEEN SIGNS OF VIS IMPROVEMENT AT
MANY SITES. ACCORDING TO THE OBS IT SEEMS AS THOUGH MUCH OF THE
FOG IS ELEVATED AT THIS POINT...MAINLY AFFECTING THE RIDGE TOPS. SEVERAL
OBSERVATIONS ACROSS EASTERN KY ARE ALSO STILL REPORTING TEMPS AT
OR JUST BELOW 32 DEGREES...SO WILL CONTINUE MENTION OF FREEZING
FOG AS WELL IN THE GRIDS FOR THE NEXT HOUR. CURRENT SPS
HIGHLIGHTING PATCHY DENSE FOG AND POSSIBLE SLICK CONDITIONS FROM
FREEZING FOG/SLICK ROADWAYS WILL BE ALLOWED TO EXPIRE AT 7AM...AS
FOG SHOULD CONTINUE LIFTING/MIXING OUT AND TEMPERATURES WILL BE
WARMING AFTER THIS POINT.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 349 AM EST SAT MAR 5 2016
LINGERING LLVL MOISTURE AND STRONG SUBSIDENCE IN PLACE THROUGH THE
FIRST PART OF THE NIGHT HAS LED TO FOG DEVELOPMENT ACROSS MUCH OF
THE CWA. GIVEN TEMPERATURES AT OR BELOW FREEZING IN MANY LOCATIONS
AS WELL...THIS ALSO CREATED A SET UP FOR POTENTIAL FREEZING FOG. AN
AREA OF LOW PRESSURE IS CURRENTLY MOVING EASTWARD INTO THE UPPER
GREAT LAKES REGION AS OF 8Z THIS MORNING. THIS IS PUSHING THE
SURFACE HIGH IN PLACE EAST OF THE REGION...AND ALLOWING MID AND
UPPER LEVEL MOISTURE TO BEGIN FILTERING INTO THE REGION. DESPITE
THIS...SOUNDINGS STILL SUPPORT A DECENT LLVL INVERSION WHICH WILL
LIKELY KEEP THE FOG AND FREEZING FOG IN PLACE THROUGHOUT THE REST OF
THE NIGHT.
BY 12Z THIS MORNING...THE LOW IS EXPECTED TO BEGIN QUICKLY DROPPING
SOUTHEASTWARD...CLIPPING THE FAR NE PORTION OF THE STATE BY LATE
THIS AFTERNOON...BEFORE EXITING EASTWARD OVERNIGHT. THIS QUICK DROP
SOUTHWARD WILL LIKELY CLEAR OUT ANY REMAINING FOG ACROSS THE REGION.
OVERALL THIS SYSTEM IS BOTH FAST MOVING AND RELATIVELY WEAK.
HOWEVER...THERE WILL BE ENOUGH MOISTURE SUPPORT FROM LLVL SRLY WINDS
TO PROMOTE SOME SCATTERED BUT LIGHT PRECIP POTENTIAL ACROSS THE CWA.
LATEST HI RES MODELS ARE SHOWING PRECIP DEVELOPING ALONG OUR FAR NW
CWA AROUND OR JUST AFTER 12Z THIS MORNING...WITH SCATTERED ACTIVITY
OVERSPREADING FROM NW TO SE THROUGHOUT THE DAY...THEN EXITING TO OUR
EAST OVERNIGHT. BEST QPF AND POPS WILL BE ACROSS THE NORTHERN AND
FAR EASTERN CWA...CLOSEST TO THE CENTER OF THE LOW.
WILL CONTINUE TO MONITOR THE TEMPERATURES AS THE PRECIP BEGINS TO
NEAR THE REGION THIS MORNING...AS IT IS LIKELY THAT BELOW FREEZING
TEMPS COULD LEAD TO SOME SNOW AT ONSET...BEFORE CHANGING OVER TO ALL
RAIN AS CONDITIONS WARM TO ABOVE FREEZING AFTER 12Z. OVERALL...NOT
LOOKING AT ANY ACCUMULATIONS IF SNOW DOES OCCUR...AND SHOULD BE A
PRETTY QUICK TURNOVER. OTHERWISE...TEMPERATURES WILL REMAIN ABOVE
FREEZING THROUGHOUT THE DURATION OF THE EVENT...SO REST OF PRECIP
SHOULD FALL AS ALL RAIN.
AMPLIFIED RIDGING WILL SHIFT EASTWARD ACROSS KY BEHIND THE EXITING
SHORTWAVE AND LOW PRESSURE SYSTEM TONIGHT AND THROUGH THE DAY
SUNDAY. WITH LINGERING MOISTURE IN PLACE ONCE MORE TONIGHT...AND
STRONG SUBSIDENCE TAKING HOLD...EXPECT SOME FOG DEVELOPMENT TO
RESULT ONCE MORE. IT IS POSSIBLE THAT THERE COULD BE SOME WIDESPREAD
AND/OR DENSE FOG IN LOCATIONS THAT RECEIVE RAINFALL TODAY...AND NEAR
SOME BODIES OF WATER. HOWEVER...GIVEN THE LOW CONFIDENCE ON WHERE
BEST IMPACTS FROM RAIN WILL BE...JUST STUCK WITH PATCHY FOG MENTION
ACROSS ENTIRE CWA AT THIS TIME. SURFACE HIGH PRESSURE WILL ACCOMPANY
THIS AMPLIFIED RIDGING...CROSSING DIRECTLY OVER KY DURING THE DAY
SUNDAY. AS A RESULT...EXPECT LIGHT WINDS...CLEARING SKIES...AND
TEMPERATURES WARMING INTO THE MID 50S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 359 AM EST SAT MAR 5 2016
WARMING TEMPERATURES AND A DRY START TO THE WEEK REMAIN IN THE
OFFING COURTESY OF BUILDING HEIGHTS/THICKNESSES ASSOCIATED WITH
BROAD EASTERN CONUS RIDGING. FURTHER WARMING WILL ENSUE AS FLOW
BACKS SOUTHWEST ALOFT IN RESPONSE TO AN UPPER LEVEL LOW DIGGING
THROUGH BAJA CALIFORNIA INTO CHIHUAHUA MEXICO. WELL ABOVE NORMAL
TEMPERATURES WILL BE THE RULE WITH HIGHS LOOKING TO TOP OUT BETWEEN
THE MID 60S TO MID 70S AS LOWS FROM TUESDAY MORNING INTO THE WEEKEND
ONLY FALL INTO THE MID 40S TO MID 50S.
GIVEN THE DEEP SOUTHERN TRACK OF THE AFOREMENTIONED SYSTEM...SURFACE
LOW PRESSURE DEVELOPING ACROSS THE SOUTHERN PLAINS WILL BE SLOW TO
EJECT EASTWARD IN AN AMPLIFIED PATTERN AS SURFACE RIDGING
ESTABLISHES A LENGTHY RESIDENCE TIME ACROSS THE MID TO SOUTHERN
ATLANTIC COAST. THIS WILL LIKELY KEEP ANY EARLIER WEEK
RAINFALL...RESULTING FROM AN INITIAL SHORTWAVE IMPULSE...WELL WEST
OF INTERSTATE 71. PROSPECTS FOR RAINFALL ACROSS CENTRAL INTO EASTERN
KENTUCKY LOOK TO BECOME MUCH BETTER FOR MID-LATE WEEK AS UPPER
ENERGY APPROACHES IN TANDEM WITH A SURFACE LOW AND PLENTY OF DEEP
LAYER MOISTURE. APPRECIABLE THUNDER CHANCES CONTINUE TO LOOK
POSSIBLE AS LONG AS INSTABILITY CAN MATERIALIZE AMID PLENTY OF MID-
HIGH CLOUD COVER. A NORTHERN STREAM TROUGH MAY ALSO ATTEMPT TO DIVE
FAR ENOUGH SOUTH TO AID IN PROVIDING ADDITIONAL LIFT FOR
SHOWER/THUNDERSTORM POTENTIAL. DEPENDING ON THE TRACK/EVOLUTION OF
THE UPPER LOW...RAINFALL COULD VERY WELL LAST INTO THE WEEKEND. WILL
HAVE TO MONITOR HEAVY RAIN/FLOODING THREAT GOING FORWARD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 713 AM EST SAT MAR 5 2016
A LOW PRESSURE SYSTEM IS CURRENTLY LOCATED OVER THE UPPER GREAT
LAKES AND IS EXPECTED TO DROP SOUTHWARD AND ACROSS EASTERN KY BY
THIS AFTERNOON. THIS WILL RESULT IN SCATTERED LIGHT RAIN SHOWERS
ACROSS MUCH OF THE AREA THROUGHOUT THE DAY...WITH BEST CHANCES AT
KSYM AND KSJS...CLOSER TO THE CENTER OF THE LOW PRESSURE SYSTEM. KEPT
WITH VCSH MENTION THROUGHOUT THE DAY /STARTING WITH KSYM AT 13Z/ DUE
TO THE SCATTERED NATURE OF THE SHOWERS AND LOW CONFIDENCE ON WHEN
A SPECIFIC TAF SITE WILL BE IMPACTED AND TO WHAT DEGREE. THE LOW
PRESSURE SYSTEM AND ASSOCIATED RAIN WILL QUICKLY EXIT EASTWARD
OVERNIGHT. AS HIGH PRESSURE FILLS IN...ANOTHER SUBSIDENCE/LLVL
MOISTURE WILL SET UP...LIKELY LEADING TO MORE FOG DEVELOPMENT
ACROSS THE REGION. OVERALL...WINDS SHOULD REMAIN LIGHT THROUGHOUT
THE TAF PERIOD...PREDOMINATELY FROM THE SW BEFORE BECOMING MORE
WRLY BEHIND THE PASSING COLD FRONT AFTER 0Z THIS EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...JMW
LONG TERM...GUSEMAN
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
959 AM EST SAT MAR 5 2016
.UPDATE...
HAVE ALL BUT REMOVED FREEZING DRIZZLE MENTION...AS 700 MB COLD OF
-14 TO -15 C SLOWLY TRACKS THROUGH SOUTHEAST MICHIGAN DURING THE
REMINDER OF THE DAY SUPPORTING ALL SNOW...WITH RADAR TRENDS
SUPPORTING MORE CONVECTIVE SNOW BANDS/HIGHER RATES...AND HAVE GONE
AHEAD AND RAISED ACCUMULATIONS TO ACCOUNT FOR 2 INCH TOTALS ACROSS
WASHTENAW/LENAWEE COUNTIES...AND WITH THE SLOW MOVING CONVERGENCE
ZONE AND PROLONGED PERIOD THROUGH THE AFTERNOON HOURS...3 INCHES
CAN`T BE RULED OUT.
&&
.PREV DISCUSSION...ISSUED 826 AM EST SAT MAR 5 2016
UPDATE...
QUICK UPDATE TO RAISE POPS AND CARRY MORE SNOW (VS FREEZING
DRIZZLE BASED ON LATEST RADAR TRENDS)...AS MID LEVEL CIRCULATION
ROTATING THROUGH CENTRAL LAKE MICHIGAN/SOUTHWEST LOWER MICHIGAN
PROVIDES SUFFICIENT FORCING ON THE NORTHEAST FLANK TO SUPPORT SNOW
SHOWERS...AS IR SHOWS CLOUD TOP COOLING AND SUFFICIENT ICE NUCLEI.
THE WEAK LOW LEVEL CIRCULATION WILL SLOWLY TRACK
SOUTHEAST...EXPECTED TO MOVE THROUGH LENAWEE COUNTY AND INTO
NORTHWEST OHIO LATE THIS AFTERNOON. SHOULD BE ABLE TO GRIND OUT AT
LEAST AN INCH OF SNOW ACCUMULATION ALONG AND WEST OF U.S. 23 UP TO
ABOUT M-59. WILL HAVE TO WATCH OUT FOR LOCALIZED HIGHER AMOUNTS
IF CONVECTIVE ELEMENTS ARE MORE VIGOROUS.
&&
.AVIATION...ISSUED 505 AM EST SAT MAR 5 2016
INITIAL ROUND OF SNOW WILL EXIT EAST OF THE TERMINAL BY 12Z. SURFACE
OBSERVATIONS AND RADAR IMAGERY THEN SUPPORT IFR CEILINGS...FOG
AND LIGHT FREEZING DRIZZLE SPREADING INTO THE AREA FROM OVER
WISCONSIN AS LOW PRESSURE OVER THE WESTERN GREAT LAKES TRACKS
TOWARDS THE OHIO VALLEY. THE DRIZZLE AND FOG WILL OCCUR AS DRIER AIR
IN THE MID-LEVELS ARRIVES...WHICH WILL ALSO MAKE THE THREAT FOR SNOW
DURING THIS TIMEFRAME VERY LOW. ADDITIONAL MOISTURE WILL WRAP IN AS
LOW PRESSURE TRACKS SOUTH OF THE AREA THIS AFTERNOON...ALLOWING A
SECOND ROUND OF LIGHT SNOW TO AFFECT THE TERMINALS MAINLY FROM PTK
SOUTH. ADDITIONAL ACCUMULATIONS SHOULD BE UNDER 0.5 INCHES. CEILINGS
SHOULD REMAIN IFR HOWEVER. A RIDGE OF HIGH PRESSURE WILL SLIDE IN
OVERHEAD TONIGHT...ENDING THE THREAT FOR PRECIPITATION. CALM
CONDITIONS WILL THEN PROMOTE THE DEVELOPMENT OF FOG AND STRATUS
OVERNIGHT. WILL FAVOR FOG FROM FNT SOUTH...CLOSER TO THE RIDGE AXIS
WHERE WINDS SHOULD BE CALM...AND LEAN MORE TOWARDS STRATUS ALONG THE
NORTHERN PERIPHERY OF THE RIDGE AXIS AT MBS OVERNIGHT.
FOR DTW...IFR CEILINGS...BR...AND -FZDZ OBSERVED UPSTREAM OVER
WISCONSIN AND FAR WESTERN MICHIGAN SHOULD MOVE WEST TOWARDS DTW
EARLY IN THE TAF PERIOD. THIS SHOULD LAST INTO AFTERNOON UNTIL
ADDITIONAL MOISTURE WORKS INTO THE AREA...BRINGING ANOTHER ROUND
OF SNOW TO THE AREA. ACCUMULATIONS UP TO 0.5 INCHES ARE EXPECTED. IFR
CONDITIONS SHOULD LIFT THIS EVENING...WITH MVFR FOG FILLING IN
OVERNIGHT AS HIGH PRESSURE AND CALM CONDITIONS SPREAD INTO LOWER
MICHIGAN.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILINGS AOB 5000 FEET TODAY AND THIS EVENING. LOW
OVERNIGHT.
* MEDIUM FOR FREEZING DRIZZLE AS PRECIPITATION TYPE BETWEEN 12-
17Z. HIGH FOR SNOW AS PRECIPITATION TYPE THIS AFTERNOON.
&&
PREV DISCUSSION...ISSUED 309 AM EST SAT MAR 5 2016
DISCUSSION...
LIGHT SNOW OVERSPREAD MUCH OF SE MI OVERNIGHT. SFC OBSERVATIONS AND
RADAR SUGGEST SOME LOCALS /PARTICULARLY SOUTH OF THE I-69 CORRIDOR/
HAVE BEEN EXPERIENCING INTERVALS OF FAIRLY GOOD SNOWFALL RATES. THIS
SNOW IS OCCURRING WITHIN A REGION OF MID LEVEL ISENTROPIC ASCENT
AHEAD OF AN UPPER SHORT WAVE NOW OVER WISCONSIN...AIDED BY A LEAD
SHORT WAVE IMPULSE NOW ROTATING INTO SE MI. THE UPSTREAM MID LEVEL
TROUGH WILL ROTATE INTO THE OHIO VALLEY BY AFTERNOON...WITH THE
ASSOCIATED SFC LOW /OVER CNTRL WISCONSIN AS OF 07Z/ TRACKING INTO
NRN INDIANA BY EARLY AFTERNOON. THE REGIONAL WATER VAPOR LOOP SHOWS
THE AXIS OF DEEP LAYER MOISTURE ALREADY OVER SE MI...WITH MID LEVEL
DRY AIR FAST MOVING INTO SW LOWER MI. THIS LOSS OF MID LEVEL
MOISTURE IS LEADING TO AN ABRUPT END TO THE LIGHT SNOW OVER SW LOWER
ATTM. MODEL RH PROGS AND SOUNDINGS /WITH SUPPORT FROM THE WATER
VAPOR LOOP/ INDICATE THE MID LEVEL DRY AIR WILL OVERSPREAD SE MI BY
12Z. THE RESULTING BRIEF DURATION OF THE SNOW EARLY THIS MORNING
WILL KEEP ACCUMS TO AN INCH OR LESS /WITH THE HIGHEST AMOUNTS SOUTH
OF I-69/.
DESPITE THE LOSS OF MID LEVEL MOISTURE...THERE WILL BE AN ADDITIONAL
INFLUX OF LOW LEVEL MOISTURE /SUB 850MB/ DRIVEN INTO SE MI DURING
THE MORNING. THIS WILL PROVIDE A GOOD SET UP FOR SOME FREEZING
DRIZZLE. THIS AND THE AMOUNT OF FZDZ REPORTS ACROSS WISCONSIN
SUPPORT ADDING AREAS OF FZDZ TO THE MORNING FORECAST. BY THE TIME
THAT CONDITIONS BECOME OPTIMAL FOR FZDZ...SFC TEMPS SHOULD BE
WARMING INTO THE LOWER 30S AND LIKELY ABOVE FREEZING BY NOON. THIS
AND THE POTENTIAL SHORT DURATION OF ANY DRIZZLE WILL SUPPORT HOLDING
OFF ON ANY TYPE OF WINTER WX ADVISORIES FOR THE TIME BEING.
DEEP LAYER MOISTURE WILL ROTATE BACK INTO SE MI THIS AFTERNOON. WITH
SOME STEEP MID LEVEL LAPSE RATES AND DIURNAL INSTABILITY...SNOW
SHOWER ACTIVITY IS POSSIBLE. THE NAM AND HRRR SUGGEST SOME FGEN
DEVELOPMENT ALONG THE MID TROPOSPHERIC FRONT...GENERALLY SOUTH OF
THE M 59 CORRIDOR EARLY IN THE AFTERNOON. THIS WILL NOT ONLY WARRANT
HIGHER POPS IN THESE LOCALS BUT ALSO SUGGEST SOME ADDITIONAL LIGHT
AFTERNOON SNOW ACCUMS /POSSIBLY A HALF INCH/.
SFC HIGH PRESSURE WILL EXPAND ACROSS SE TONIGHT AMIDST RISING MID
LEVEL HEIGHTS IN THE WAKE OF THE DEPARTING UPPER TROUGH. LOW LEVEL
ANTICYCLONIC FLOW AND DRY AIR ADVECTION SHOULD CLEAR THE LOW CLOUDS
OUT LATE IN THE NIGHT...SUPPORTING A BRIEF PERIOD OF DECENT
RADIATIONAL COOLING. IF THIS COOLING OCCURS A LITTLE EARLIER...LATER
SHIFTS WILL HAVE TO CONSIDER ADDING FOG TO THE FORECAST.
LONG WAVE RIDGE AMPLIFICATION ACROSS THE ERN US EARLY NEXT WEEK AND
THE ESTABLISHMENT OF STRENGTHENING SOUTHWEST FLOW FROM THE SRN
PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES WILL SUPPORT A
DRAMATIC WARM UP BEGINNING SUNDAY AND PERSISTING THROUGH AT LEAST
TUESDAY. DESPITE THE SNOW COVER...THE STRONG LOW LEVEL WARM AIR
ADVECTION WITHIN THE WELL MIXED SW FLOW WILL SUPPORT TEMPS ON THE
HIGH END OF GUIDANCE /40S SUNDAY...50S MON...60S TUES/. CONSENSUS
AMONG THE MEDIUM RANGE MODEL SUITE INDICATE BETTER RAINFALL CHANCES
MID TO LATE WEEK AS MUCH DEEPER MOISTURE GETS ADVECTED INTO THE
GREAT LAKES. A GOOD DEAL OF FCST UNCERTAINTY REVOLVES AROUND TIMING
A BACK DOOR COLD FRONT THROUGH THE AREA NEXT WEEK. MODEL SOLUTIONS
DIVERGE WITH RESPECT TO TIMING AND AMPLITUDE OF AN UPPER WAVE
TRACKING ACROSS CANADA WHICH RESULTS IN A LARGE SPREAD IN TIMING
THIS BACK DOOR COLD FRONT INTO SE MI. IT LOOKS AS THOUGH THIS FRONT
WILL MOVE THROUGH SOMETIME IN THE WED TO THURS TIME FRAME AND WILL
HAVE THE POTENTIAL TO BRING MUCH COOLER LAKE MODIFIED BOUNDARY LAYER
AIR INTO THE AREA /WITH WARM MOIST SOUTHWEST FLOW ALOFT STILL
PROVING PERIODIC CHANCES FOR RAIN SHOWERS/.
MARINE...
WINDS WILL REMAIN LIGHT TODAY...GENERALLY UNDER 10 KNOTS...AS LOW
PRESSURE SLIDES FROM THE WESTERN GREAT LAKES INTO THE OHIO VALLEY
TODAY...AND THEN A RIDGE OF HIGH PRESSURE SHIFTS INTO THE AREA
TONIGHT. LOW PRESSURE TRACKING ACROSS HUDSON BAY AND ONTARIO SUNDAY
INTO SUNDAY NIGHT WILL THEN PROVIDE A TIGHTER SURFACE PRESSURE
GRADIENT OVER THE AREA...CAUSING WINDS TO INCREASE. THE STRONGEST
WINDS LOOK TO OCCUR OVER THE OPEN WATERS OF LAKE HURON...WITH SPEEDS
INTO THE 20 TO 25 KNOT RANGE. GUSTS SHOULD REMAIN BELOW GALE FORCE
HOWEVER AS WARMER AIR SURGING INTO THE AREA WILL PROVIDE A HIGH
DEGREE OF STABILITY OVER THE COLD LAKE WATERS.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......SF
AVIATION.....HLO
DISCUSSION...SC
MARINE.......HLO
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
826 AM EST SAT MAR 5 2016
.UPDATE...
QUICK UPDATE TO RAISE POPS AND CARRY MORE SNOW (VS FREEZING
DRIZZLE BASED ON LATEST RADAR TRENDS)...AS MID LEVEL CIRCULATION
ROTATING THROUGH CENTRAL LAKE MICHIGAN/SOUTHWEST LOWER MICHIGAN
PROVIDES SUFFICIENT FORCING ON THE NORTHEAST FLANK TO SUPPORT SNOW
SHOWERS...AS IR SHOWS CLOUD TOP COOLING AND SUFFICIENT ICE NUCLEI.
THE WEAK LOW LEVEL CIRCULATION WILL SLOWLY TRACK
SOUTHEAST...EXPECTED TO MOVE THROUGH LENAWEE COUNTY AND INTO
NORTHWEST OHIO LATE THIS AFTERNOON. SHOULD BE ABLE TO GRIND OUT AT
LEAST AN INCH OF SNOW ACCUMULATION ALONG AND WEST OF U.S. 23 UP TO
ABOUT M-59. WILL HAVE TO WATCH OUT FOR LOCALIZED HIGHER AMOUNTS
IF CONVECTIVE ELEMENTS ARE MORE VIGOROUS.
&&
.AVIATION...ISSUED 505 AM EST SAT MAR 5 2016
INITIAL ROUND OF SNOW WILL EXIT EAST OF THE TERMINAL BY 12Z. SURFACE
OBSERVATIONS AND RADAR IMAGERY THEN SUPPORT IFR CEILINGS...FOG
AND LIGHT FREEZING DRIZZLE SPREADING INTO THE AREA FROM OVER
WISCONSIN AS LOW PRESSURE OVER THE WESTERN GREAT LAKES TRACKS
TOWARDS THE OHIO VALLEY. THE DRIZZLE AND FOG WILL OCCUR AS DRIER AIR
IN THE MID-LEVELS ARRIVES...WHICH WILL ALSO MAKE THE THREAT FOR SNOW
DURING THIS TIMEFRAME VERY LOW. ADDITIONAL MOISTURE WILL WRAP IN AS
LOW PRESSURE TRACKS SOUTH OF THE AREA THIS AFTERNOON...ALLOWING A
SECOND ROUND OF LIGHT SNOW TO AFFECT THE TERMINALS MAINLY FROM PTK
SOUTH. ADDITIONAL ACCUMULATIONS SHOULD BE UNDER 0.5 INCHES. CEILINGS
SHOULD REMAIN IFR HOWEVER. A RIDGE OF HIGH PRESSURE WILL SLIDE IN
OVERHEAD TONIGHT...ENDING THE THREAT FOR PRECIPITATION. CALM
CONDITIONS WILL THEN PROMOTE THE DEVELOPMENT OF FOG AND STRATUS
OVERNIGHT. WILL FAVOR FOG FROM FNT SOUTH...CLOSER TO THE RIDGE AXIS
WHERE WINDS SHOULD BE CALM...AND LEAN MORE TOWARDS STRATUS ALONG THE
NORTHERN PERIPHERY OF THE RIDGE AXIS AT MBS OVERNIGHT.
FOR DTW...IFR CEILINGS...BR...AND -FZDZ OBSERVED UPSTREAM OVER
WISCONSIN AND FAR WESTERN MICHIGAN SHOULD MOVE WEST TOWARDS DTW
EARLY IN THE TAF PERIOD. THIS SHOULD LAST INTO AFTERNOON UNTIL
ADDITIONAL MOISTURE WORKS INTO THE AREA...BRINGING ANOTHER ROUND
OF SNOW TO THE AREA. ACCUMULATIONS UP TO 0.5 INCHES ARE EXPECTED. IFR
CONDITIONS SHOULD LIFT THIS EVENING...WITH MVFR FOG FILLING IN
OVERNIGHT AS HIGH PRESSURE AND CALM CONDITIONS SPREAD INTO LOWER
MICHIGAN.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILINGS AOB 5000 FEET TODAY AND THIS EVENING. LOW
OVERNIGHT.
* MEDIUM FOR FREEZING DRIZZLE AS PRECIPITATION TYPE BETWEEN 12-
17Z. HIGH FOR SNOW AS PRECIPITATION TYPE THIS AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 309 AM EST SAT MAR 5 2016
DISCUSSION...
LIGHT SNOW OVERSPREAD MUCH OF SE MI OVERNIGHT. SFC OBSERVATIONS AND
RADAR SUGGEST SOME LOCALS /PARTICULARLY SOUTH OF THE I-69 CORRIDOR/
HAVE BEEN EXPERIENCING INTERVALS OF FAIRLY GOOD SNOWFALL RATES. THIS
SNOW IS OCCURRING WITHIN A REGION OF MID LEVEL ISENTROPIC ASCENT
AHEAD OF AN UPPER SHORT WAVE NOW OVER WISCONSIN...AIDED BY A LEAD
SHORT WAVE IMPULSE NOW ROTATING INTO SE MI. THE UPSTREAM MID LEVEL
TROUGH WILL ROTATE INTO THE OHIO VALLEY BY AFTERNOON...WITH THE
ASSOCIATED SFC LOW /OVER CNTRL WISCONSIN AS OF 07Z/ TRACKING INTO
NRN INDIANA BY EARLY AFTERNOON. THE REGIONAL WATER VAPOR LOOP SHOWS
THE AXIS OF DEEP LAYER MOISTURE ALREADY OVER SE MI...WITH MID LEVEL
DRY AIR FAST MOVING INTO SW LOWER MI. THIS LOSS OF MID LEVEL
MOISTURE IS LEADING TO AN ABRUPT END TO THE LIGHT SNOW OVER SW LOWER
ATTM. MODEL RH PROGS AND SOUNDINGS /WITH SUPPORT FROM THE WATER
VAPOR LOOP/ INDICATE THE MID LEVEL DRY AIR WILL OVERSPREAD SE MI BY
12Z. THE RESULTING BRIEF DURATION OF THE SNOW EARLY THIS MORNING
WILL KEEP ACCUMS TO AN INCH OR LESS /WITH THE HIGHEST AMOUNTS SOUTH
OF I-69/.
DESPITE THE LOSS OF MID LEVEL MOISTURE...THERE WILL BE AN ADDITIONAL
INFLUX OF LOW LEVEL MOISTURE /SUB 850MB/ DRIVEN INTO SE MI DURING
THE MORNING. THIS WILL PROVIDE A GOOD SET UP FOR SOME FREEZING
DRIZZLE. THIS AND THE AMOUNT OF FZDZ REPORTS ACROSS WISCONSIN
SUPPORT ADDING AREAS OF FZDZ TO THE MORNING FORECAST. BY THE TIME
THAT CONDITIONS BECOME OPTIMAL FOR FZDZ...SFC TEMPS SHOULD BE
WARMING INTO THE LOWER 30S AND LIKELY ABOVE FREEZING BY NOON. THIS
AND THE POTENTIAL SHORT DURATION OF ANY DRIZZLE WILL SUPPORT HOLDING
OFF ON ANY TYPE OF WINTER WX ADVISORIES FOR THE TIME BEING.
DEEP LAYER MOISTURE WILL ROTATE BACK INTO SE MI THIS AFTERNOON. WITH
SOME STEEP MID LEVEL LAPSE RATES AND DIURNAL INSTABILITY...SNOW
SHOWER ACTIVITY IS POSSIBLE. THE NAM AND HRRR SUGGEST SOME FGEN
DEVELOPMENT ALONG THE MID TROPOSPHERIC FRONT...GENERALLY SOUTH OF
THE M 59 CORRIDOR EARLY IN THE AFTERNOON. THIS WILL NOT ONLY WARRANT
HIGHER POPS IN THESE LOCALS BUT ALSO SUGGEST SOME ADDITIONAL LIGHT
AFTERNOON SNOW ACCUMS /POSSIBLY A HALF INCH/.
SFC HIGH PRESSURE WILL EXPAND ACROSS SE TONIGHT AMIDST RISING MID
LEVEL HEIGHTS IN THE WAKE OF THE DEPARTING UPPER TROUGH. LOW LEVEL
ANTICYCLONIC FLOW AND DRY AIR ADVECTION SHOULD CLEAR THE LOW CLOUDS
OUT LATE IN THE NIGHT...SUPPORTING A BRIEF PERIOD OF DECENT
RADIATIONAL COOLING. IF THIS COOLING OCCURS A LITTLE EARLIER...LATER
SHIFTS WILL HAVE TO CONSIDER ADDING FOG TO THE FORECAST.
LONG WAVE RIDGE AMPLIFICATION ACROSS THE ERN US EARLY NEXT WEEK AND
THE ESTABLISHMENT OF STRENGTHENING SOUTHWEST FLOW FROM THE SRN
PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES WILL SUPPORT A
DRAMATIC WARM UP BEGINNING SUNDAY AND PERSISTING THROUGH AT LEAST
TUESDAY. DESPITE THE SNOW COVER...THE STRONG LOW LEVEL WARM AIR
ADVECTION WITHIN THE WELL MIXED SW FLOW WILL SUPPORT TEMPS ON THE
HIGH END OF GUIDANCE /40S SUNDAY...50S MON...60S TUES/. CONSENSUS
AMONG THE MEDIUM RANGE MODEL SUITE INDICATE BETTER RAINFALL CHANCES
MID TO LATE WEEK AS MUCH DEEPER MOISTURE GETS ADVECTED INTO THE
GREAT LAKES. A GOOD DEAL OF FCST UNCERTAINTY REVOLVES AROUND TIMING
A BACK DOOR COLD FRONT THROUGH THE AREA NEXT WEEK. MODEL SOLUTIONS
DIVERGE WITH RESPECT TO TIMING AND AMPLITUDE OF AN UPPER WAVE
TRACKING ACROSS CANADA WHICH RESULTS IN A LARGE SPREAD IN TIMING
THIS BACK DOOR COLD FRONT INTO SE MI. IT LOOKS AS THOUGH THIS FRONT
WILL MOVE THROUGH SOMETIME IN THE WED TO THURS TIME FRAME AND WILL
HAVE THE POTENTIAL TO BRING MUCH COOLER LAKE MODIFIED BOUNDARY LAYER
AIR INTO THE AREA /WITH WARM MOIST SOUTHWEST FLOW ALOFT STILL
PROVING PERIODIC CHANCES FOR RAIN SHOWERS/.
MARINE...
WINDS WILL REMAIN LIGHT TODAY...GENERALLY UNDER 10 KNOTS...AS LOW
PRESSURE SLIDES FROM THE WESTERN GREAT LAKES INTO THE OHIO VALLEY
TODAY...AND THEN A RIDGE OF HIGH PRESSURE SHIFTS INTO THE AREA
TONIGHT. LOW PRESSURE TRACKING ACROSS HUDSON BAY AND ONTARIO SUNDAY
INTO SUNDAY NIGHT WILL THEN PROVIDE A TIGHTER SURFACE PRESSURE
GRADIENT OVER THE AREA...CAUSING WINDS TO INCREASE. THE STRONGEST
WINDS LOOK TO OCCUR OVER THE OPEN WATERS OF LAKE HURON...WITH SPEEDS
INTO THE 20 TO 25 KNOT RANGE. GUSTS SHOULD REMAIN BELOW GALE FORCE
HOWEVER AS WARMER AIR SURGING INTO THE AREA WILL PROVIDE A HIGH
DEGREE OF STABILITY OVER THE COLD LAKE WATERS.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......SF
AVIATION.....HLO
DISCUSSION...SC
MARINE.......HLO
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
651 AM EST SAT MAR 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EST SAT MAR 5 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWS A RIDGE OVER THE ROCKIES
AND A TROF OVER ERN NAMERICA. SHORTWAVE THAT BROUGHT SNOW INTO UPPER
MI OVER THE LAST 12HRS OR SO IS TRACKING SE THRU WI. THIS WILL BE
THE FINAL SHORTWAVE TO DROP SE THRU THE AREA BEFORE A TRANSITION TO
A WARM SPLIT FLOW PATTERN WITH ABOVE NORMAL HEIGHTS AND W TO SW FLOW
ACROSS THE UPPER GREAT LAKES NEXT WEEK. RADAR TRENDS OVER THE LAST
COUPLE OF HRS SHOW SNOW DIMINISHING OVER UPPER MI...AND UPSTREAM...
KDLH RADAR SHOWS VERY LITTLE PCPN REMAINING. THERE WERE OBS AND
REPORTS OF SOME -FZDZ EARLIER IN THE NIGHT OVER WRN UPPER MI AND NRN
WI AS THE HEAVIER SNOW DEPARTED. RECENTLY...THERE ARE FEWER OBS
SHOWING UNKNOWN PCPN...SO -FZDZ MAY BE DIMINISHING.
WITH SHORTWAVE CONTINUING SE TODAY...DIMINISHING PCPN WILL END FROM
NW TO SE. SOUTHERLY FLOW ON LAKE MI PERSISTS THRU MID TO LATE
MORNING WHICH SHOULD HELP WEAKLY LAKE ENHANCED SNOW TO LINGER.
THUS...HIGHEST POPS WILL PAINTED OVER THE E THIS MORNING WITH
PERHAPS ANOTHER HALF INCH OR SO OF SNOW ACCUMULATION. TO THE W...
WILL KEEP A MENTION OF -FZDZ/-SN MAINLY IN THE COUNTIES BORDERING WI
FOR THE NEXT FEW HRS. SATELLITE IMAGERY SHOWS CLEARING NOT THAT FAR
AWAY ACROSS NRN LAKE SUPERIOR. WITH HIGH PRES RIDGE BUILDING INTO
THE UPPER GREAT LAKES THIS AFTN...LOW-LEVEL NORTHERLY WINDS AHEAD OF
THE RIDGE WILL DIMINISH. THIS INCREASES THE UNCERTAINTY IN HOW MUCH
CLEARING WILL OCCUR...ESPECIALLY SINCE UPSLOPE FLOW OFF THE LAKE
UNDER A LOWERING INVERSION SHOULD GREATLY SLOW THE CLEARING PROCESS.
KEWEENAW OBVIOUSLY HAS THE BEST CHC OF AT LEAST PARTIALLY CLEARING
OUT TODAY GIVEN THE CLOSE PROXIMITY OF CLEAR SKIES ALREADY EARLY
THIS MORNING. FOR NOW...FCST WILL SHOW A VERY GRADUAL DECREASE IN
CLOUDS FROM THE N AND NW THIS AFTN INTO THIS EVENING.
CLOUD FCST INTO TONIGHT REMAINS A BIT TRICKY. IF THE EXTENSIVE LOW
CLOUDS ACROSS MN/WI PERSIST THRU THE DAY...THESE CLOUDS MAY MOVE
BACK INTO THE AREA TONIGHT ONCE S TO SW FLOW DEVELOPS/INCREASES
AFTER THE HIGH PRES RIDGE PASSES. OTHERWISE...PROVIDED MUCH OF
TODAYS CLOUD COVER DEPARTS BY EVENING...THERE WILL BE AN OPPORTUNITY
FOR TEMPS TO FALL QUICKLY THIS EVENING UNDER LIGHT/CALM WIND. LEANED
FCST TO THE COLDER BIAS CORRECTED REGIONAL/GLOBAL CANADIAN MODELS
DUE TO THEIR NORMAL SUPERIOR PERFORMANCE IN RADIATIONAL COOLING
SITUATIONS. TRADITIONAL COLD SPOTS WILL FALL DOWN INTO THE MID TEENS
IF SKIES ARE MOSTLY CLEAR THIS EVENING.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 349 AM EST SAT MAR 5 2016
ADVERTISED EARLY SPRING PREVIEW IS STILL ON TRACK FOR EARLY NEXT
WEEK AND BEYOND. SUBSTANTIAL WARM ADVECTION KICKS IN ON SUNDAY.
PRESSURE GRADIENT WILL TIGHTEN SIGNIFICANTLY BETWEEN SURFACE
LOW/SHORTWAVE MOVING THROUGH NORTHERN ONTARIO AND HIGH PRESSURE
ALONG THE EAST COAST. 85H TEMPS CLIMB INTO THE PLUS 5 TO 8C RANGE.
EVEN WITH THE STABLE THERMAL PROFILE 92H WINDS ARE FORECAST UP TO 40
KNOTS SO EXPECT WINDS TO BE PRETTY GUSTY. NAM REMAINS
CONSISTENT...AND TO A LESSER EXTENT THE GFS...IN SHOWING ENOUGH
MOISTENING THROUGH THE DAY THAT THERE MAY EVEN BE SOME LIGHT
PRECIPITATION OVER EASTERN AREAS BY LATE IN THE DAY. WILL INTRODUCE
SOME SLIGHT CHANCE POPS ACROSS THE EAST FOR SOME LIGHT RAIN/DRIZZLE.
TEMPS ON SUNDAY WILL CLIMB INTO THE 40S WEST WHILE LAKE MICHIGAN
COOLING WITH THE STRONG SOUTHWESTERLY WINDS WILL KEEP TEMPS IN THE
UPPER 30S ACROSS THE EAST.
THE BEST CHANCES FOR ANY WIDESPREAD PRECIPITATION...ALBEIT
RELATIVELY LIGHT...WILL OCCUR DURING THE MONDAY THROUGH TUESDAY
NIGHT TIME PERIOD. WHILE TEMPERATURES WILL BE WELL ABOVE NORMAL...IT
WILL PROBABLY BE PRETTY GLOOMY DURING THIS PERIOD. CONTINUED WARM
ADVECTION...DEWPOINTS CLIMBING INTO THE 30S AND 40S...AND A MELTING
SNOWPACK WILL YIELD PLENTY OF LOW CLOUDS...PATCHY FOG...AND DRIZZLE.
SHEARING OUT SHORTWAVE EJECTING WEST OF THE AREA ON TUESDAY WITH
SURFACE LOW PASSING NORTHWEST OF LAKE SUPERIOR WILL BRING THE BEST
CHANCE OF RAIN ON TUESDAY. WITH DYNAMICAL FORCING ON THE WANE AND
LINGERING MID LEVEL DRY AIR ANY PRECIPITATION WILL BE PRETTY LIGHT.
AS TRAILING COLD FRONT CROSSES THE AREA LATE TUESDAY AND WITH FAIRLY
STEEP MID LEVEL LAPSE RATES STILL CANNOT RULE THE POSSIBILITY OF A
THUNDERSTORM ALONG THE FRONT. HOWEVER...CAPPING MAY REMAIN TOO
STRONG TO ALLOW ANY DEEP CONVECTION. DESPITE THE CLOUDS
TEMPERATURES WILL APPROACH 50 FOR MANY ON MONDAY AND INTO THE 50S ON
TUESDAY AWAY FROM THE COOLING INFLUENCES OF THE LAKES...ESPECIALLY
LAKE MICHIGAN.
DRIER AIR ALONG WITH SOME COOLING BEHIND THE FRONT WILL ALLOW
PRECIPITATION TO COME TO AN END TUESDAY NIGHT.
FORECAST LOOKS DRY DURING THE WEDNESDAY THROUGH FRIDAY PERIOD. AFTER
A BRIEF COOL DOWN WEDNESDAY...ALTHOUGH STILL ABOVE NORMAL...MILD
PACIFIC AIR WILL RETURN FOR LATE IN THE WEEK WITH DAYTIME TEMPS ONCE
AGAIN APPROACHING 50 FOR MANY BY LATE IN THE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 650 AM EST SAT MAR 5 2016
WITH LOW PRES DEPARTING TO THE SE AND DRIER AIR GRADUALLY FILTERING
INTO UPPER MI FROM THE N AND NW...EXPECT IMPROVING CONDITIONS TODAY.
AT KIWD...INITIAL IFR/LIFR CONDITIONS WILL IMPROVE TO MVFR BY LATE
MORNING...THEN VFR BY LATE AFTN/EARLY EVENING IF NOT SOONER. CIGS
HAVE ALREADY RISEN TO VFR AT KCMX AS DRIER AIR HAS SLIPPED INTO THE
KEWEENAW. HOWEVER...SOME PERIODS OF MVFR CIGS ARE STILL EXPECTED
THIS MORNING. AT KSAW...MVFR CIGS WILL PROBABLY PERSIST UNTIL LATE
AFTN/EARLY EVENING UNDER UPSLOPE FLOW OFF LAKE SUPERIOR.
HOWEVER...NOT OUT OF THE QUESTION FOR SOME PERIODS OF IFR THIS
MORNING UNDER UPSLOPE FLOW AND ALSO FOR VFR CONDITIONS TO DEVELOP
SOONER THIS AFTN. AFTER HIGH PRES RIDGE PASSES THIS EVENING...WINDS
WILL BEGIN TO INCREASE ABOVE SFC BASED INVERSION. THIS WILL LEAD TO
LLWS AT KIWD LATE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EST SAT MAR 5 2016
EXPECT LIGHT WINDS...MOSTLY UNDER 15KT TO BE THE RULE ACROSS LAKE
SUPERIOR TODAY UNDER A WEAK PRES GRADIENT WITH HIGH PRES RIDGE
ARRIVING IN THE AFTN. PRES GRADIENT WILL THEN TIGHTENT TONIGHT AND
SUN AS THE RIDGE SHIFTS TO THE E COAST AND A LOW PRES MOVES ACROSS
SCNTRL CANADA. S TO SW WINDS WILL RAMP UP TO AS HIGH AS 30KT LATE
TONIGHT AND SUN. NOT OUT OF THE QUESTION THAT A FEW GALE FORCE GUSTS
COULD OCCUR OVER EASTERN LAKE SUPERIOR SUN. WINDS WILL THEN DIMINISH
SUN NIGHT/MON UNDER A WEAKENING PRES GRADIENT. AS LOW PRES TRACKS
FROM THE WESTERN PLAINS MON MORNING TO NORTHERN ONTARIO TUE AND
QUEBEC WED...WINDS WILL AGAIN INCREASE TO 15-25KT AT TIMES TUE/WED.
SOME FOG MAY FORM OVER THE CHILLY WATERS MON NIGHT/TUE AS MOISTER
AIR MOVES INTO THE UPPER LAKES AHEAD OF THE LOW PRES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MZ
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
505 AM EST SAT MAR 5 2016
.AVIATION...
INITIAL ROUND OF SNOW WILL EXIT EAST OF THE TERMINAL BY 12Z. SURFACE
OBSERVATIONS AND RADAR IMAGERY THEN SUPPORT IFR CEILINGS...FOG
AND LIGHT FREEZING DRIZZLE SPREADING INTO THE AREA FROM OVER
WISCONSIN AS LOW PRESSURE OVER THE WESTERN GREAT LAKES TRACKS
TOWARDS THE OHIO VALLEY. THE DRIZZLE AND FOG WILL OCCUR AS DRIER AIR
IN THE MID-LEVELS ARRIVES...WHICH WILL ALSO MAKE THE THREAT FOR SNOW
DURING THIS TIMEFRAME VERY LOW. ADDITIONAL MOISTURE WILL WRAP IN AS
LOW PRESSURE TRACKS SOUTH OF THE AREA THIS AFTERNOON...ALLOWING A
SECOND ROUND OF LIGHT SNOW TO AFFECT THE TERMINALS MAINLY FROM PTK
SOUTH. ADDITIONAL ACCUMULATIONS SHOULD BE UNDER 0.5 INCHES. CEILINGS
SHOULD REMAIN IFR HOWEVER. A RIDGE OF HIGH PRESSURE WILL SLIDE IN
OVERHEAD TONIGHT...ENDING THE THREAT FOR PRECIPITATION. CALM
CONDITIONS WILL THEN PROMOTE THE DEVELOPMENT OF FOG AND STRATUS
OVERNIGHT. WILL FAVOR FOG FROM FNT SOUTH...CLOSER TO THE RIDGE AXIS
WHERE WINDS SHOULD BE CALM...AND LEAN MORE TOWARDS STRATUS ALONG THE
NORTHERN PERIPHERY OF THE RIDGE AXIS AT MBS OVERNIGHT.
FOR DTW...IFR CEILINGS...BR...AND -FZDZ OBSERVED UPSTREAM OVER
WISCONSIN AND FAR WESTERN MICHIGAN SHOULD MOVE WEST TOWARDS DTW
EARLY IN THE TAF PERIOD. THIS SHOULD LAST INTO AFTERNOON UNTIL
ADDITIONAL MOISTURE WORKS INTO THE AREA...BRINGING ANOTHER ROUND
OF SNOW TO THE AREA. ACCUMULATIONS UP TO 0.5 INCHES ARE EXPECTED. IFR
CONDITIONS SHOULD LIFT THIS EVENING...WITH MVFR FOG FILLING IN
OVERNIGHT AS HIGH PRESSURE AND CALM CONDITIONS SPREAD INTO LOWER
MICHIGAN.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILINGS AOB 5000 FEET TODAY AND THIS EVENING. LOW
OVERNIGHT.
* MEDIUM FOR FREEZING DRIZZLE AS PRECIPITATION TYPE BETWEEN 12-
17Z. HIGH FOR SNOW AS PRECIPITATION TYPE THIS AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 309 AM EST SAT MAR 5 2016
DISCUSSION...
LIGHT SNOW OVERSPREAD MUCH OF SE MI OVERNIGHT. SFC OBSERVATIONS AND
RADAR SUGGEST SOME LOCALS /PARTICULARLY SOUTH OF THE I-69 CORRIDOR/
HAVE BEEN EXPERIENCING INTERVALS OF FAIRLY GOOD SNOWFALL RATES. THIS
SNOW IS OCCURRING WITHIN A REGION OF MID LEVEL ISENTROPIC ASCENT
AHEAD OF AN UPPER SHORT WAVE NOW OVER WISCONSIN...AIDED BY A LEAD
SHORT WAVE IMPULSE NOW ROTATING INTO SE MI. THE UPSTREAM MID LEVEL
TROUGH WILL ROTATE INTO THE OHIO VALLEY BY AFTERNOON...WITH THE
ASSOCIATED SFC LOW /OVER CNTRL WISCONSIN AS OF 07Z/ TRACKING INTO
NRN INDIANA BY EARLY AFTERNOON. THE REGIONAL WATER VAPOR LOOP SHOWS
THE AXIS OF DEEP LAYER MOISTURE ALREADY OVER SE MI...WITH MID LEVEL
DRY AIR FAST MOVING INTO SW LOWER MI. THIS LOSS OF MID LEVEL
MOISTURE IS LEADING TO AN ABRUPT END TO THE LIGHT SNOW OVER SW LOWER
ATTM. MODEL RH PROGS AND SOUNDINGS /WITH SUPPORT FROM THE WATER
VAPOR LOOP/ INDICATE THE MID LEVEL DRY AIR WILL OVERSPREAD SE MI BY
12Z. THE RESULTING BRIEF DURATION OF THE SNOW EARLY THIS MORNING
WILL KEEP ACCUMS TO AN INCH OR LESS /WITH THE HIGHEST AMOUNTS SOUTH
OF I-69/.
DESPITE THE LOSS OF MID LEVEL MOISTURE...THERE WILL BE AN ADDITIONAL
INFLUX OF LOW LEVEL MOISTURE /SUB 850MB/ DRIVEN INTO SE MI DURING
THE MORNING. THIS WILL PROVIDE A GOOD SET UP FOR SOME FREEZING
DRIZZLE. THIS AND THE AMOUNT OF FZDZ REPORTS ACROSS WISCONSIN
SUPPORT ADDING AREAS OF FZDZ TO THE MORNING FORECAST. BY THE TIME
THAT CONDITIONS BECOME OPTIMAL FOR FZDZ...SFC TEMPS SHOULD BE
WARMING INTO THE LOWER 30S AND LIKELY ABOVE FREEZING BY NOON. THIS
AND THE POTENTIAL SHORT DURATION OF ANY DRIZZLE WILL SUPPORT HOLDING
OFF ON ANY TYPE OF WINTER WX ADVISORIES FOR THE TIME BEING.
DEEP LAYER MOISTURE WILL ROTATE BACK INTO SE MI THIS AFTERNOON. WITH
SOME STEEP MID LEVEL LAPSE RATES AND DIURNAL INSTABILITY...SNOW
SHOWER ACTIVITY IS POSSIBLE. THE NAM AND HRRR SUGGEST SOME FGEN
DEVELOPMENT ALONG THE MID TROPOSPHERIC FRONT...GENERALLY SOUTH OF
THE M 59 CORRIDOR EARLY IN THE AFTERNOON. THIS WILL NOT ONLY WARRANT
HIGHER POPS IN THESE LOCALS BUT ALSO SUGGEST SOME ADDITIONAL LIGHT
AFTERNOON SNOW ACCUMS /POSSIBLY A HALF INCH/.
SFC HIGH PRESSURE WILL EXPAND ACROSS SE TONIGHT AMIDST RISING MID
LEVEL HEIGHTS IN THE WAKE OF THE DEPARTING UPPER TROUGH. LOW LEVEL
ANTICYCLONIC FLOW AND DRY AIR ADVECTION SHOULD CLEAR THE LOW CLOUDS
OUT LATE IN THE NIGHT...SUPPORTING A BRIEF PERIOD OF DECENT
RADIATIONAL COOLING. IF THIS COOLING OCCURS A LITTLE EARLIER...LATER
SHIFTS WILL HAVE TO CONSIDER ADDING FOG TO THE FORECAST.
LONG WAVE RIDGE AMPLIFICATION ACROSS THE ERN US EARLY NEXT WEEK AND
THE ESTABLISHMENT OF STRENGTHENING SOUTHWEST FLOW FROM THE SRN
PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES WILL SUPPORT A
DRAMATIC WARM UP BEGINNING SUNDAY AND PERSISTING THROUGH AT LEAST
TUESDAY. DESPITE THE SNOW COVER...THE STRONG LOW LEVEL WARM AIR
ADVECTION WITHIN THE WELL MIXED SW FLOW WILL SUPPORT TEMPS ON THE
HIGH END OF GUIDANCE /40S SUNDAY...50S MON...60S TUES/. CONSENSUS
AMONG THE MEDIUM RANGE MODEL SUITE INDICATE BETTER RAINFALL CHANCES
MID TO LATE WEEK AS MUCH DEEPER MOISTURE GETS ADVECTED INTO THE
GREAT LAKES. A GOOD DEAL OF FCST UNCERTAINTY REVOLVES AROUND TIMING
A BACK DOOR COLD FRONT THROUGH THE AREA NEXT WEEK. MODEL SOLUTIONS
DIVERGE WITH RESPECT TO TIMING AND AMPLITUDE OF AN UPPER WAVE
TRACKING ACROSS CANADA WHICH RESULTS IN A LARGE SPREAD IN TIMING
THIS BACK DOOR COLD FRONT INTO SE MI. IT LOOKS AS THOUGH THIS FRONT
WILL MOVE THROUGH SOMETIME IN THE WED TO THURS TIME FRAME AND WILL
HAVE THE POTENTIAL TO BRING MUCH COOLER LAKE MODIFIED BOUNDARY LAYER
AIR INTO THE AREA /WITH WARM MOIST SOUTHWEST FLOW ALOFT STILL
PROVING PERIODIC CHANCES FOR RAIN SHOWERS/.
MARINE...
WINDS WILL REMAIN LIGHT TODAY...GENERALLY UNDER 10 KNOTS...AS LOW
PRESSURE SLIDES FROM THE WESTERN GREAT LAKES INTO THE OHIO VALLEY
TODAY...AND THEN A RIDGE OF HIGH PRESSURE SHIFTS INTO THE AREA
TONIGHT. LOW PRESSURE TRACKING ACROSS HUDSON BAY AND ONTARIO SUNDAY
INTO SUNDAY NIGHT WILL THEN PROVIDE A TIGHTER SURFACE PRESSURE
GRADIENT OVER THE AREA...CAUSING WINDS TO INCREASE. THE STRONGEST
WINDS LOOK TO OCCUR OVER THE OPEN WATERS OF LAKE HURON...WITH SPEEDS
INTO THE 20 TO 25 KNOT RANGE. GUSTS SHOULD REMAIN BELOW GALE FORCE
HOWEVER AS WARMER AIR SURGING INTO THE AREA WILL PROVIDE A HIGH
DEGREE OF STABILITY OVER THE COLD LAKE WATERS.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....HLO
DISCUSSION...SC
MARINE.......HLO
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS BISMARCK ND
933 AM CST SAT MAR 5 2016
.UPDATE...
ISSUED AT 931 AM CST SAT MAR 5 2016
NO MAJOR CHANGES TO THE FORECAST WERE WARRANTED SO FAR THIS
MORNING. MAIN CHANGE WAS TO SLOW DOWN THE CLEARING FROM JAMESTOWN
EASTWARD WHERE THE CLOUDS HAVE BEEN A LITTLE SLOW TO MOVE OUT.
THE LATEST SHORT TERM MODELS STILL SHOW THE CLOUDS EXITING...WITH
ONLY SCATTERED HIGH CLOUDS LATER THIS AFTERNOON.
UPDATE ISSUED AT 646 AM CST SAT MAR 5 2016
NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE CYCLE...BUT WE
DID DELAY THE EXIT OF LOW CLOUDS /STRATUS/ IN THE SOUTHERN JAMES
RIVER VALLEY A BIT UNTIL MID MORNING BASED ON SATELLITE AND HRRR
TRENDS. OTHERWISE...THE 12 UTC BISMARCK SOUNDING REVEALED PLENTY
OF MID-LEVEL WARMING AND DRYING SINCE LAST EVENING...SUPPORTING
THE GOING WARM FORECAST FOR TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CST SAT MAR 5 2016
WARMER...BREEZY...AND DRY CONDITIONS HIGHLIGHT THE SHORT TERM
PERIOD. SOUTHERLY WINDS/WARM AIR ADVECTION DEVELOP TODAY ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. A MINOR COLD FRONT PASSES
THROUGH SATURDAY NIGHT.
THE LATEST WATER VAPOR AND IR IMAGERY LOOP INDICATE MID/UPPER
LEVEL RIDGING OVER THE NORTHERN ROCKIES THIS MORNING WITH
SCATTERED HIGH CLOUDS RIDING ATOP THE RIDGE INTO WESTERN NORTH
DAKOTA. FOG/STRATUS IMAGERY LOOP CONTINUES TO SHOW AN AREA OF LOW
CLOUDS IN THE JAMES RIVER VALLEY. THIS IS FORECAST TO EXIT BY 12Z
SATURDAY. THE TREND WILL BE FOR THE UPPER RIDGE TO SHIFT EAST AND
GRADUALLY FLATTEN/BECOME BROADER THROUGH TONIGHT...AS A PAIR OF
SHORTWAVES PUSH INTO THE RIDGE. THE FIRST SHORTWAVE IS BEST
DEFINED AT 700MB AND CURRENTLY IS LOCATED IN SOUTH CENTRAL
MONTANA. THIS WILL STEADILY MOVE INTO SOUTH CENTRAL NORTH DAKOTA
BY 00Z SUNDAY. NOT EXPECTING ANYTHING SIGNIFICANT AS THERE IS NO
SURFACE LOW REFLECTION. THIS SHORTWAVE WILL MAINLY SERVE TO
FLATTEN THE OVERALL HEIGHT FIELD/RIDGE AXIS AS IT PROPAGATES
THROUGH. THE SECOND SHORTWAVE NOW INTO SOUTHWEST BRITISH COLUMBIA
WILL SLIDE ACROSS SOUTHERN CANADA INDUCING A SURFACE LOW/COLD
FRONT IN SOUTHERN ALBERTA THIS AFTERNOON. IT WILL THEN MOVE EAST
AND GRAZE NORTH DAKOTA SATURDAY NIGHT WITH A WIND SHIFT AND WEAK
COLD AIR ADVECTION.
FOR TODAY...THE CANOPY OF THE 1000-500MB THICKNESS RIDGE HOVERS
OVER THE SOUTHWEST...RESULTING IN THE WARMEST/DRIEST AIR TO RESIDE
HERE. AFTERNOON HIGHS WILL CLIMB INTO THE MID/UPPER 60S SOUTHWEST.
ELSEWHERE EXPECT HIGHS IN THE 50S CENTRAL TO 40S FROM THE TURTLE
MOUNTAINS INTO THE JAMES RIVER VALLEY. UTILIZED A 50/50 COMBINATION
BLEND OF THE HRRR EXPERIMENTAL 2M HOURLY RH FIELD AND OFFICIAL
GRIDDED FORECAST TO YIELD MINIMUM RELATIVE HUMIDITIES IN THE 15
TO 20 PERCENT RANGE SOUTHWEST. THIS SEEMS LOGICAL GIVEN UPSTREAM
FLOW AND RELATED AIRMASS FROM FRIDAY HAVING ADVECTED IN FROM
WYOMING. THE HRRR RH FIELD VERIFIED WELL IN NORTH DAKOTA AS WELL
AS UPSTREAM IN THE LAST 24HR. WINDS TODAY WILL BE WEAKEST IN THE
FAR SOUTHWEST WHERE AFTERNOON RELATIVE HUMIDITIES WILL BE LOWEST.
WINDS WILL STEADILY INCREASE INTO THE BREEZY CATEGORY (15-25MPH)
FOR CENTRAL NORTH DAKOTA THIS AFTERNOON.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 344 AM CST SAT MAR 5 2016
ABOVE-NORMAL TEMPERATURES AND MAINLY DRY WEATHER WILL PREVAIL FOR
THE NEXT WEEK.
ON SUNDAY...DAILY RECORD HIGHS MAY FALL GIVEN 850-MB TEMPERATURES
IN THE 97.5 TO 99TH PERCENTILE FOR THIS TIME OF THE YEAR...NEARLY
FULL SUNSHINE...DRY SOILS...AND DORMANT VEGETATION...ALL OF WHICH
WILL SUPPORT EFFICIENT HEATING. WE ARE STILL CALLING FOR HIGHS IN
THE 60S F IN MOST AREAS AND A FEW 70 F READINGS ARE LIKELY ACROSS
SOUTHWEST AND SOUTH CENTRAL ND. MIXING IS FORECAST TO BE SOMEWHAT
MORE SHALLOW THAN ON SATURDAY BASED ON 00 UTC MODEL SOUNDINGS AND
THAT RAISES A BIT OF CONCERN FOR WARMING...BUT MORE THAN LIKELY
THAT WILL JUST ENSURE WINDS WILL STAY RELATIVELY LIGHT. SUNDAY IS
APT TO BE A TRULY STELLAR EARLY MARCH DAY.
THEREAFTER...A PACIFIC COLD FRONT WILL CROSS THE AREA MONDAY AS A
WEAK SHORTWAVE TROUGH EJECTS ACROSS THE REGION OUT OF A SPLITTING
TROUGH THAT WILL KEEP ITS CORE WELL SOUTH IN TX AND MEXICO. WE DO
HAVE A LOW-GRADE SHOWER CHANCE IN THE FORECAST BEHIND THE FRONT
MONDAY THROUGH EARLY TUESDAY. PROGRESSIVE...QUASI-ZONAL FLOW WILL
THEN OCCUR IN THE NORTHERN STREAM THE MIDDLE PART OF THE WEEK AND
THAT WILL YIELD MAINLY DRY WEATHER. THE 00 UTC GFS AND ECMWF BOTH
SUGGEST RIDGING REBUILDING AGAIN BY LATE WEEK....WITH THE 00 UTC
NAEFS EVEN CALLING FOR 850-MB TEMPERATURE ANOMALIES IN THE 90TH
PERCENTILE BY FRIDAY. THAT IS A SIGNIFICANT SIGNAL IN A LONG-LEAD
ENSEMBLE FORECAST...SUGGESTING HIGHS COULD ONCE AGAIN END UP WELL
INTO THE 60S F /WARMER THAN OUR CURRENT FORECAST/ BY LATE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 931 AM CST SAT MAR 5 2016
ALL TERMINALS IN VFR STATUS THROUGH THE TAF PERIOD EXCEPT
KJMS...WHERE MVFR CIGS WILL LINGER UNTIL 17Z SATURDAY...THEN VFR.
BREEZY SSE/S WINDS BETWEEN 15KT AND 25KT AT KBIS/KJMS DURING THE
AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 931 AM CST SAT MAR 5 2016
DESPITE MINIMUM RELATIVE HUMIDITIES IN THE 15 TO 20 PERCENT
RANGE OVER SOUTHWEST ND TODAY...WINDS WILL NOT BE STRONG ENOUGH
FOR CRITICAL FIRE WEATHER CRITERIA TO BE MET. SUSTAINED SOUTHERLY
WINDS WILL WEAKEN THROUGH THE AFTERNOON TO BETWEEN 10 AND 15
MPH...JUST AS RELATIVE HUMIDITIES REACH THEIR MINIMUM AS MENTIONED
ABOVE. THUS WILL NOT ISSUE ANY HIGHLIGHTS AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...KS
LONG TERM...CJS
AVIATION...KS
FIRE WEATHER...KS/CJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
646 AM CST SAT MAR 5 2016
.UPDATE...
ISSUED AT 646 AM CST SAT MAR 5 2016
NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE CYCLE...BUT WE
DID DELAY THE EXIT OF LOW CLOUDS /STRATUS/ IN THE SOUTHERN JAMES
RIVER VALLEY A BIT UNTIL MID MORNING BASED ON SATELLITE AND HRRR
TRENDS. OTHERWISE...THE 12 UTC BISMARCK SOUNDING REVEALED PLENTY
OF MID-LEVEL WARMING AND DRYING SINCE LAST EVENING...SUPPORTING
THE GOING WARM FORECAST FOR TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CST SAT MAR 5 2016
WARMER...BREEZY...AND DRY CONDITIONS HIGHLIGHT THE SHORT TERM
PERIOD. SOUTHERLY WINDS/WARM AIR ADVECTION DEVELOP TODAY ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. A MINOR COLD FRONT PASSES
THROUGH SATURDAY NIGHT.
THE LATEST WATER VAPOR AND IR IMAGERY LOOP INDICATE MID/UPPER
LEVEL RIDGING OVER THE NORTHERN ROCKIES THIS MORNING WITH
SCATTERED HIGH CLOUDS RIDING ATOP THE RIDGE INTO WESTERN NORTH
DAKOTA. FOG/STRATUS IMAGERY LOOP CONTINUES TO SHOW AN AREA OF LOW
CLOUDS IN THE JAMES RIVER VALLEY. THIS IS FORECAST TO EXIT BY 12Z
SATURDAY. THE TREND WILL BE FOR THE UPPER RIDGE TO SHIFT EAST AND
GRADUALLY FLATTEN/BECOME BROADER THROUGH TONIGHT...AS A PAIR OF
SHORTWAVES PUSH INTO THE RIDGE. THE FIRST SHORTWAVE IS BEST
DEFINED AT 700MB AND CURRENTLY IS LOCATED IN SOUTH CENTRAL
MONTANA. THIS WILL STEADILY MOVE INTO SOUTH CENTRAL NORTH DAKOTA
BY 00Z SUNDAY. NOT EXPECTING ANYTHING SIGNIFICANT AS THERE IS NO
SURFACE LOW REFLECTION. THIS SHORTWAVE WILL MAINLY SERVE TO
FLATTEN THE OVERALL HEIGHT FIELD/RIDGE AXIS AS IT PROPAGATES
THROUGH. THE SECOND SHORTWAVE NOW INTO SOUTHWEST BRITISH COLUMBIA
WILL SLIDE ACROSS SOUTHERN CANADA INDUCING A SURFACE LOW/COLD
FRONT IN SOUTHERN ALBERTA THIS AFTERNOON. IT WILL THEN MOVE EAST
AND GRAZE NORTH DAKOTA SATURDAY NIGHT WITH A WIND SHIFT AND WEAK
COLD AIR ADVECTION.
FOR TODAY...THE CANOPY OF THE 1000-500MB THICKNESS RIDGE HOVERS
OVER THE SOUTHWEST...RESULTING IN THE WARMEST/DRIEST AIR TO RESIDE
HERE. AFTERNOON HIGHS WILL CLIMB INTO THE MID/UPPER 60S SOUTHWEST.
ELSEWHERE EXPECT HIGHS IN THE 50S CENTRAL TO 40S FROM THE TURTLE
MOUNTAINS INTO THE JAMES RIVER VALLEY. UTILIZED A 50/50 COMBINATION
BLEND OF THE HRRR EXPERIMENTAL 2M HOURLY RH FIELD AND OFFICIAL
GRIDDED FORECAST TO YIELD MINIMUM RELATIVE HUMIDITIES IN THE 15
TO 20 PERCENT RANGE SOUTHWEST. THIS SEEMS LOGICAL GIVEN UPSTREAM
FLOW AND RELATED AIRMASS FROM FRIDAY HAVING ADVECTED IN FROM
WYOMING. THE HRRR RH FIELD VERIFIED WELL IN NORTH DAKOTA AS WELL
AS UPSTREAM IN THE LAST 24HR. WINDS TODAY WILL BE WEAKEST IN THE
FAR SOUTHWEST WHERE AFTERNOON RELATIVE HUMIDITIES WILL BE LOWEST.
WINDS WILL STEADILY INCREASE INTO THE BREEZY CATEGORY (15-25MPH)
FOR CENTRAL NORTH DAKOTA THIS AFTERNOON.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 344 AM CST SAT MAR 5 2016
ABOVE-NORMAL TEMPERATURES AND MAINLY DRY WEATHER WILL PREVAIL FOR
THE NEXT WEEK.
ON SUNDAY...DAILY RECORD HIGHS MAY FALL GIVEN 850-MB TEMPERATURES
IN THE 97.5 TO 99TH PERCENTILE FOR THIS TIME OF THE YEAR...NEARLY
FULL SUNSHINE...DRY SOILS...AND DORMANT VEGETATION...ALL OF WHICH
WILL SUPPORT EFFICIENT HEATING. WE ARE STILL CALLING FOR HIGHS IN
THE 60S F IN MOST AREAS AND A FEW 70 F READINGS ARE LIKELY ACROSS
SOUTHWEST AND SOUTH CENTRAL ND. MIXING IS FORECAST TO BE SOMEWHAT
MORE SHALLOW THAN ON SATURDAY BASED ON 00 UTC MODEL SOUNDINGS AND
THAT RAISES A BIT OF CONCERN FOR WARMING...BUT MORE THAN LIKELY
THAT WILL JUST ENSURE WINDS WILL STAY RELATIVELY LIGHT. SUNDAY IS
APT TO BE A TRULY STELLAR EARLY MARCH DAY.
THEREAFTER...A PACIFIC COLD FRONT WILL CROSS THE AREA MONDAY AS A
WEAK SHORTWAVE TROUGH EJECTS ACROSS THE REGION OUT OF A SPLITTING
TROUGH THAT WILL KEEP ITS CORE WELL SOUTH IN TX AND MEXICO. WE DO
HAVE A LOW-GRADE SHOWER CHANCE IN THE FORECAST BEHIND THE FRONT
MONDAY THROUGH EARLY TUESDAY. PROGRESSIVE...QUASI-ZONAL FLOW WILL
THEN OCCUR IN THE NORTHERN STREAM THE MIDDLE PART OF THE WEEK AND
THAT WILL YIELD MAINLY DRY WEATHER. THE 00 UTC GFS AND ECMWF BOTH
SUGGEST RIDGING REBUILDING AGAIN BY LATE WEEK....WITH THE 00 UTC
NAEFS EVEN CALLING FOR 850-MB TEMPERATURE ANOMALIES IN THE 90TH
PERCENTILE BY FRIDAY. THAT IS A SIGNIFICANT SIGNAL IN A LONG-LEAD
ENSEMBLE FORECAST...SUGGESTING HIGHS COULD ONCE AGAIN END UP WELL
INTO THE 60S F /WARMER THAN OUR CURRENT FORECAST/ BY LATE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 646 AM CST SAT MAR 5 2016
ALL TERMINALS IN VFR STATUS THROUGH THE TAF PERIOD EXCEPT
KJMS...WHERE MVFR CIGS WILL LINGER UNTIL 16Z SATURDAY...THEN VFR.
BREEZY SSE/S WINDS BETWEEN 15KT AND 25KT AT KBIS/KJMS DURING THE
AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 646 AM CST SAT MAR 5 2016
DESPITE MINIMUM RELATIVE HUMIDITIES IN THE 15 TO 20 PERCENT
RANGE OVER SOUTHWEST ND TODAY...WINDS WILL NOT BE STRONG ENOUGH
FOR CRITICAL FIRE WEATHER CRITERIA TO BE MET. SUSTAINED SOUTHERLY
WINDS WILL WEAKEN THROUGH THE AFTERNOON TO BETWEEN 10 AND 15
MPH...JUST AS RELATIVE HUMIDITIES REACH THEIR MINIMUM AS MENTIONED
ABOVE. THUS WILL NOT ISSUE ANY HIGHLIGHTS AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CJS
SHORT TERM...KS
LONG TERM...CJS
AVIATION...KS
FIRE WEATHER...KS/CJS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
737 AM EST SAT MAR 5 2016
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL MOVE THROUGH THE REGION EARLY
TODAY...BEFORE ANOTHER WEAK CLIPPER TYPE SYSTEM BRINGS THE CHANCE
FOR MORE LIGHT RAIN OR SNOW LATER TODAY INTO SUNDAY MORNING. A
LARGE RIDGE OF HIGH PRESSURE WILL BUILD OVER THE EASTERN HALF OF
THE CONTINENT DURING THE UPCOMING WEEK. TEMPERATURES WILL SURGE
TO WELL ABOVE NORMAL LEVELS STARTING MONDAY...AND LAST THROUGH
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REGIONAL RADAR AND INFRARED SATL LOOP INDICATES A LARGE SHIELD OF
ALTOSTRATUS SPREADING ACROSS THE WESTERN THIRD OF THE STATE...AND
OVER A LAYER OF STRATOCU CLOUDS THAT COVERED THE CENTRAL VALLEYS
AND LOCATIONS JUST WEST OF THE SUSQ MAINSTEM. THE RADAR RETURNS
LOOK MUCH MORE OMINOUS THAN WHAT WE`RE NOTING AT METAR SITES
ACROSS OHIO AND WRN PENN. THE SEVERAL AREAS OF VERY LIGHT SNOW OR
FLURRIES WITH VSBYS AOA 7SM ARE SHOWN TO FIZZLE OUT ACROSS WRN PA
/FOR THIS MORNING INTO THE MID AFTERNOON HOURS/ BY THE LATEST
SVRL RUNS OF THE HRRR AS THE LLVLS WILL STAY DRY WITH DEWPOINTS IN
THE MID TEENS TO LOWER 20S.
A SLIGHT NUDGE OF FCST TEMPS TOWARD THE LATEST BLENDED MODEL
GUIDANCE COMBINED WITH INPUT FROM LATEST LAMP YIELDS MAX TEMPS
THIS AFTERNOON RANGING FROM THE L30S ACROSS HE HIGHEST TERRAIN OF
THE ALLEGHENIES...TO ARND 40F ACROSS THE SUSQ VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
THE BULK OF THE LIGHT SNOW /WITH THE EMPHASIS ON THE WORD LIGHT/
WILL ARRIVE VERY LATE TODAY ACROSS THE WEST...AND EARLY TONIGHT
ACROSS CENTRAL AND ERN PENN WITH THE PASSAGE OF A WEAK /1016-1018
MB/ SFC LOW AND ASSOC WEAK WAA. CONSENSUS MODEL QPF IS JUST A
FEW...TO SVRL HUNDREDTHS OF AN INCH...WHICH LEADS TO SNOWFALL
AMOUNTS SIMILAR...IF NOT LIGHTER IN MOST AREAS THAN WHAT OCCURRED
ABOUT 48 HOURS PRIOR - THURSDAY NIGHT INTO FRIDAY MORNING. THE
LAURELS COULD BE THE EXCEPTION WITH THE POTENTIAL FOR AN INCH OR
TWO OF SNOW ACCUMULATION BY EARLY SUNDAY...CONSIDERING THAT THIS
IS THE TARGET AREA FOR THE HRRR`S QPF - AS A RESULT OF BEING
CLOSEST TO THE SFC LOW TRACK ACROSS WEST VA.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AFTER SOME MORNING CLOUDS...AND FLURRIES ACROSS THE FAR SE DURING
THE MORNING...LOOK FOR BRIGHTENING SKIES BUT STILL CHILLY
CONDITIONS FOR LATE SUNDAY MORNING AND SUNDAY AFTERNOON AS HIGH
PRES BUILDS IN FROM THE WEST WITH LIGHT NW SFC FLOW.
BROAD CONSENSUS AMONG MED RANGE GUIDANCE IN A MARKED WARM UP
DURING THE FIRST HALF OF THE UPCOMING WEEK...AS AN ANOMALOUS
UPPER LVL RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND ASSOC SW
FLOW OVR PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER 12Z
ECENS. TEMPS WILL TAKE A RUN AT 70F BY WED OVR SOUTHERN PA.
MODELS ARE IN BETTER AGREEMENT ON BRINGING A QUASI-STATIONARY
FRONTAL BOUNDARY RUNNING FROM THE MISS VALLEY THRU THE GRT LKS AT
INTERFACE OF E COAST RIDGE AND PLAINS TROF THROUGH PA BY
MIDWEEK...AS HIGH PRESSURE TRACKING EASTWARD ACROSS CANADA WILL
NUDGE THE FRONT SOUTHWARD AND PIVOT IT FROM MORE OF A N-S
ORIENTATION TO A W-E DIRECTION. THIS COULD BRING THE NEXT BEST
CHANCE FOR PRECIPITATION AS WEAK WAVES COULD RIPPLE TOWARD PA
ALONG THE PORTION OF THE /WARM/ FRONT OVER THE OHIO VALLEY. GIVEN
THE STRONG WAA IT LOOKS TO BE ALL RAIN...WITH PRECIP BRACKETED
BETWEEN LATE IN THE DAY WED AND FRI. THE GFS IS MORE AGGRESSIVE
WITH ONSET OF PRECIP AND QPF AMOUNTS THAN THE ECMWF...BUT EITHER
WAY IT LOOKS TO BE A SHOWERY END TO THE WEEK AND TEMPS GRADUALLY
COOL BACK DOWN BUT REMAIN ABOVE NORMAL.
&&
.AVIATION /13Z SATURDAY THROUGH WEDNESDAY/...
FOR THE 05/12Z TAFS THROUGH 06/12Z
ISSUED AT 735 AM EST SAT MAR 5 2016
MVFR TO LOW VFR CIGS /2500-5000FT AGL/ WILL PREVAIL TODAY WITH
VERY LIGHT SNOW/FLURRIES OVER THE WESTERN AIRSPACE. LOW PRESSURE
TRACKING SOUTHEAST FROM WI THRU WV/KY WILL BRING LIGHT SNOW AND
MVFR VIS THIS EVENING THROUGH TONIGHT INTO EARLY SUNDAY MORNING.
HIGHEST CONFIDENCE IN IFR IS AT JST. PATTERN FAVORS STUBBORN LOW
CLOUDS GETTING TRAPPED UNDER RIDGE OF HIGH PRESSURE/SUBSIDENCE
INVERSION WITH LOW CIGS CONTINUING INTO SUNDAY MORNING.
OUTLOOK...SUNDAY-WEDNESDAY
SUN...MVFR CIGS BECOMING VFR. NO SIG WX.
MON-TUE...VFR/NO SIG WX.
WED...LOW CIGS/RAIN POSSIBLE NORTHWEST AIRSPACE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
602 AM EST SAT MAR 5 2016
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL MOVE THROUGH THE REGION EARLY
TODAY...BEFORE ANOTHER WEAK CLIPPER TYPE SYSTEM BRINGS THE CHANCE
FOR MORE LIGHT RAIN OR SNOW LATER TODAY INTO SUNDAY MORNING. A
LARGE RIDGE OF HIGH PRESSURE WILL BUILD OVER THE EASTERN HALF OF
THE CONTINENT DURING THE UPCOMING WEEK. TEMPERATURES WILL SURGE
TO WELL ABOVE NORMAL LEVELS STARTING MONDAY...AND LAST THROUGH
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REGIONAL RADAR AND INFRARED SATL LOOP INDICATES A LARGE SHIELD OF
ALTOSTRATUS SPREADING ACROSS THE WESTERN THIRD OF THE STATE...AND
OVER A LAYER OF STRATOCU CLOUDS THAT COVERED THE CENTRAL VALLEYS
AND LOCATIONS JUST WEST OF THE SUSQ MAINSTEM. THE RADAR RETURNS
LOOK MUCH MORE OMINOUS THAN WHAT WE`RE NOTING AT METAR SITES
ACROSS OHIO AND WRN PENN. THE SEVERAL AREAS OF VERY LIGHT SNOW OR
FLURRIES WITH VSBYS AOA 7SM ARE SHOWN TO FIZZLE OUT ACROSS WRN PA
/FOR THIS MORNING INTO THE MID AFTERNOON HOURS/ BY THE LATEST
SVRL RUNS OF THE HRRR AS THE LLVLS WILL STAY DRY WITH DEWPOINTS IN
THE MID TEENS TO LOWER 20S.
A SLIGHT NUDGE OF FCST TEMPS TOWARD THE LATEST BLENDED MODEL
GUIDANCE COMBINED WITH INPUT FROM LATEST LAMP YIELDS MAX TEMPS
THIS AFTERNOON RANGING FROM THE L30S ACROSS HE HIGHEST TERRAIN OF
THE ALLEGHENIES...TO ARND 40F ACROSS THE SUSQ VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
THE BULK OF THE LIGHT SNOW /WITH THE EMPHASIS ON THE WORD LIGHT/
WILL ARRIVE VERY LATE TODAY ACROSS THE WEST...AND EARLY TONIGHT
ACROSS CENTRAL AND ERN PENN WITH THE PASSAGE OF A WEAK /1016-1018
MB/ SFC LOW AND ASSOC WEAK WAA. CONSENSUS MODEL QPF IS JUST A
FEW...TO SVRL HUNDREDTHS OF AN INCH...WHICH LEADS TO SNOWFALL
AMOUNTS SIMILAR...IF NOT LIGHTER IN MOST AREAS THAN WHAT OCCURRED
ABOUT 48 HOURS PRIOR - THURSDAY NIGHT INTO FRIDAY MORNING. THE
LAURELS COULD BE THE EXCEPTION WITH THE POTENTIAL FOR AN INCH OR
TWO OF SNOW ACCUMULATION BY EARLY SUNDAY...CONSIDERING THAT THIS
IS THE TARGET AREA FOR THE HRRR`S QFP - AS A RESULT OF BEING
CLOSEST TO THE SFC LOW TRACK ACROSS WEST VA.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AFTER SOME MORNING CLOUDS...AND FLURRIES ACROSS THE FAR SE DURING
THE MORNING...LOOK FOR BRIGHTENING SKIES BUT STILL CHILLY
CONDITIONS FOR LATE SUNDAY MORNING AND SUNDAY AFTERNOON AS HIGH
PRES BUILDS IN FROM THE WEST WITH LIGHT NW SFC FLOW.
BROAD CONSENSUS AMONG MED RANGE GUIDANCE IN A MARKED WARM UP
DURING THE FIRST HALF OF THE UPCOMING WEEK...AS AN ANOMALOUS
UPPER LVL RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND ASSOC SW
FLOW OVR PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER 12Z
ECENS. TEMPS WILL TAKE A RUN AT 70F BY WED OVR SOUTHERN PA.
MODELS ARE IN BETTER AGREEMENT ON BRINGING A QUASI-STATIONARY
FRONTAL BOUNDARY RUNNING FROM THE MISS VALLEY THRU THE GRT LKS AT
INTERFACE OF E COAST RIDGE AND PLAINS TROF THROUGH PA BY
MIDWEEK...AS HIGH PRESSURE TRACKING EASTWARD ACROSS CANADA WILL
NUDGE THE FRONT SOUTHWARD AND PIVOT IT FROM MORE OF A N-S
ORIENTATION TO A W-E DIRECTION. THIS COULD BRING THE NEXT BEST
CHANCE FOR PRECIPITATION AS WEAK WAVES COULD RIPPLE TOWARD PA
ALONG THE PORTION OF THE /WARM/ FRONT OVER THE OHIO VALLEY. GIVEN
THE STRONG WAA IT LOOKS TO BE ALL RAIN...WITH PRECIP BRACKETED
BETWEEN LATE IN THE DAY WED AND FRI. THE GFS IS MORE AGGRESSIVE
WITH ONSET OF PRECIP AND QPF AMOUNTS THAN THE ECMWF...BUT EITHER
WAY IT LOOKS TO BE A SHOWERY END TO THE WEEK AND TEMPS GRADUALLY
COOL BACK DOWN BUT REMAIN ABOVE NORMAL.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
FOR THE 05/06Z TAFS THROUGH 06/06Z
ISSUED AT 135 AM EST SAT MAR 5 2016
LOW CLOUDS TRAPPED UNDERNEATH SUBSIDENCE INVERSION WILL KEEP MVFR
TO LOW VFR CIGS /1.5-4KFT AGL/ IN PLACE THIS MORNING ACROSS THE
WRN 2/3 OF THE AIRSPACE. VFR ALONG/EAST OF IPT-MDT LINE WITH FEW-
SCT CIGS AT 5KFT. LOW PRESSURE TRACKING SOUTHEAST FROM WI THRU WV
WILL BRING LIGHT SNOW AND REDUCED CONDITIONS LATER THIS AFTERNOON
INTO TONIGHT. HIGHEST CONFIDENCE IN IFR IS AT JST.
OUTLOOK...SUNDAY-WEDNESDAY
SUN...MVFR CIGS WEST BECOMING VFR. NO SIG WX.
MON-TUE...VFR/NO SIG WX.
WED...VFR. RAIN POSSIBLE NORTHWEST AIRSPACE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/RXR
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
256 PM PST SAT MAR 5 2016
.SYNOPSIS...
MOIST WEST FLOW WILL LIKELY BRING SHOWERS TO NORTHERN AREAS THIS EVENING...
WITH A CHANCE OF SHOWERS ELSEWHERE. A COUPLE OF FRONTAL SYSTEMS WILL
THEN BRING RAIN...POSSIBLY HEAVY AT TIMES TO THE REGION. THE FIRST
WILL AFFECT THE AREA TONIGHT AND EARLY SUNDAY...AND THE SECOND LATE
SUNDAY NIGHT INTO MONDAY. THUNDERSTORMS ARE POSSIBLE MONDAY. HIGH
SNOW LEVELS WILL LOWER THROUGH MONDAY. DRY AND WARMER WEATHER IS
EXPECTED TUESDAY THROUGH MOST OF THURSDAY. ANOTHER FRONT MAY BRING
RAIN TO THE REGION LATE THURSDAY THROUGH FRIDAY.
&&
.SHORT TERM...(TDY-TUE)
WARM FRONTAL CLOUDS MOVING OVER THE AREA THIS AFTERNOON. THERE HAS
BEEN SOME ON AGAIN OFF AGAIN LIGHT RAIN ACROSS THE AREA DUES TO
THE WARM FRONT AS WELL. RADAR SHOWERS A MORE ORGANIZED AREA OF
LIGHT RAIN JUST OFF THE CENTRAL COAST ASSOC WITH THE CORE OF THE
WARM FRONT. SO CENTRAL COAST SHOULD BE SEEING A MARKED INCREASE IN
RAIN LATER THIS AFTERNOON AND EARLY EVENING.
WINDS WILL INCREASE ACROSS SLO AND SBA COUNTIES AS THE SURFACE
PRESSURE GRADIENT TIGHTENS AHEAD OF THE FRONT. SOUTH WINDS WILL
INCREASE TO 15 TO 25 MPH WITH GUSTS BETWEEN 35 AND 45 MPH.
ALL MDLS ARE IN GOOD AGREEMENT THAT A COLD FRONT JUST OFF THE NRN
CA COAST AND TRAILING TO THE SW WILL MOVE THROUGH THE AREA LATER
TONIGHT AND SUNDAY MORNING. THIS FRONT WILL BRING A 2 TO 4 HOUR
PERIOD OF MODERATE TO LOCALLY HEAVY RAIN WITH IT. IT WILL REACH
SLO COUNTY JUST BEFORE MIDNIGHT AND EXIT THE COUNTY A FEW HOURS
BEFORE SUNRISE...IT WILL ENTER SBA COUNTY JUST AFTER MIDNIGHT AND
EXIT THE COUNTY AROUND DAWN...IT WILL ENTER VTA COUNTY JUST BEFORE
DAWN AND EXIT THE COUNTY IN THE EARLY MORNING...IT WILL ENTER L.A.
COUNTY AT DAWN AND DEPART BY MID MORNING. THE CHANCE OF RAIN WILL
GREATLY DIMINISH BEHIND THE FRONT AND ODDS ON IT WILL BE PARTLY
CLOUDY AND DRY FOR SUNDAY AFTERNOON.
PRECIPITABLE WATER VALUES WITH THIS FRONT WILL BE AROUND 1.3
INCHES WHICH WILL HELP RAINFALL TOTALS. STILL EXPECT 0.25 TO
0.75 INCHES OF RAIN ACROSS L.A. AND VTA COUNTIES...WITH TOTALS
OVER 1 INCH POSSIBLE IN THE FOOTHILLS AND MTNS ON AND BELOW S
FACING SLOPES. ACROSS SBA AND SLO COUNTIES...EXPECT 0.75 TO 1.5
INCHES OF RAIN...WITH UP TO 2.0 INCHES ACROSS THE HIGHER TERRAIN
OF SLO COUNTY AND IN THE MTNS OF SRN SBA COUNTY. SNOW LEVELS WILL
BE HIGH WITH THIS FIRST SYSTEM...NEAR 7000 FEET. THERE COULD
LOCALLY BE A FEW INCHES OF SNOW AT THE HIGHEST ELEVATIONS.
A SECOND COLDER AND MORE DYNAMIC...BUT SLIGHTLY DRIER COLD FRONT
WILL WORK ITS WAY TOWARDS CA TONIGHT. THE FRONTS PARENT TROF WILL
TAKE ON A SLIGHT NEGATIVE TILT AND SET UP A NICE DIFFLUENT
PATTERN OVER THE REGION EARLY MONDAY. THE DYNAMICS AND INSTABILITY
WILL ALLOW FOR A CHANCE OF THUNDER MONDAY MORNING AND A SLIGHT
CHANCE IN THE COLD AIR BEHIND THE FRONT IN THE AFTERNOON. AS THE
SYSTEM TAKES ON A MORE NEGATIVE TILT THE SYSTEM WILL SLOW DOWN
SOME. RIGHT NOW IT LOOKS LIKE THE FRONT WILL PASS INTO SLO COUNTY
AT ABOUT 3 AM MONDAY MORNING AND EXIT L.A. COUNTY JUST AFTER NOON
ON MONDAY AFTERNOON.
SINCE THIS SYSTEM WILL BE COLDER...SHOWERY AND MORE DYNAMIC THAN
TONIGHT`S STORM RAINFALL RATES WILL BE A LITTLE MORE VARIABLE.
MDLS ARE STRUGGLING TO COME INTO AGREEMENT WITH RAINFALL TOTALS
WITH THE NAM NOT SEEING AS MUCH RAIN AS THE GFS OR EC SOLUTIONS.
RIGHT NOW IT LOOKS LIKE THERE WILL NOT BE MUCH IN THE WAY OF
DIFFERENCES BETWEEN THE COUNTIES AND ALL AREAS SHOULD SEE BETWEEN
AN INCH AND AN INCH AND A HALF OF RAIN WITH THIS SECOND SYSTEM.
ANY THUNDERSTORMS THAT FORM MONDAY COULD PRODUCE RAINFALL RATES
THAT EXCEED ONE HALF INCH PER HOUR...WHICH COULD CAUSE SOME
PROBLEMS IN AND BELOW RECENT BURN AREAS.
SHOWERS WILL END ACROSS THE AREA MONDAY EVENING...EXCEPT ON THE
NORTH SLOPES WHERE STRONG MOIST NLY FLOW WILL CREATE UPSLOPE SNOW
INTO EARLY TUESDAY. SNOW LEVELS WITH AND BEHIND THIS SECOND FRONT
WILL BE QUITE A BIT LOWER... POSSIBLY DOWN TO 4000 TO 5000 FEET
MONDAY AND MON NIGHT. THIS COULD CAUSE TRAVEL PROBLEMS IN THE
GRAPEVINE PORTION OF INTERSTATE 5. RIGHT NOW IT LOOKS LIKE BETWEEN
4 AND 8 INCHES OF SNOW WILL FALL ABOVE 6000 FEET ON MONDAY.
THERE WILL BE SOME FAIRLY STRONG NW WINDS BEHIND THE FRONT AND
THERE WILL BE AT LEAST ADVISORY LEVEL WINDS AND POSSIBLY WARNING
LEVEL WINDS OVER THE MTNS AND ANTELOPE VLY MONDAY NIGHT AND
TUESDAY MORNING.
A RIDGE WILL BUILD IN FROM THE SW ON TUESDAY. IT WILL USHER IN A
CLEARING AND WARMING TREND. MAX TEMPS WILL RISE TO THE UPPER 60S
OR THE LOWER 70S.
.LONG TERM...(WED-SAT)
ALL MDLS AGREE THAT RIDGING WILL DOMINATE THE AREA WED AND THU.
578 DM HGTS WILL ALL MAX TEMPS TO CLIMB INTO THE LOW TO MID 70S
ACROSS MOST OF THE CSTS AND VLYS OR ABOUT 3 TO 6 DEGREES ABOVE
NORMAL.
ANOTHER COLD FRONT WILL ZIP ACROSS THE AREA ON FRIDAY. ALL MDLS
ARE IN PRETTY GOOD AGREEMENT ABOUT THIS AND UPPED THE POPS TO
THE CHANCE RANGE. RIGHT NOW IT LOOKS LIKE A MEDIUM KIND OF SYSTEM
BUT THESE THINGS CAN CHANGE AS THE MDLS GET A CLOSER AND CLOSER
LOOK AT IT. MAX TEMPS WILL NOSE DIVE BY 10 TO 15 DEGREES,
THE GFS SEES A STORM ON SATURDAY BUT THE EC AND CANADIAN DO NOT.
FOR NOW KEPT THE AREA DRY BUT ONE SHOULD NEVER REALLY HAVE THAT
MUCH FAITH IN A DAY 7 FORECAST.
&&
.AVIATION...
05/0000Z
WILL BE OUT SHORTLY
&&
.MARINE...
05/200 PM
SOUTH WINDS WILL CONTINUE TO INCREASE OVER THE ENTIRE AREA AND
SCA CONDITIONS WILL EXIST FROM PIEDRAS BLANCAS TO SAN CLEMENTE
ISLAND EXCLUDING THE SANTA BARBARA, SANTA MONICA AND SAN PEDRO
BASINS THROUGH TO NIGHT. THE WINDS WILL LIKELY BECOME WEST SUNDAY
AND THERE IS A CHANCE SCA CONDITIONS FOR WINDS AND SEAS WILL EXIST
OVER THE ENTIRE AREA SUNDAY THROUGH SUNDAY NIGHT. THE WINDS WILL
THEN LIKELY BECOME NORTHWEST MONDAY AND THERE IS A CHANCE GALES
WILL EXIST OVER THE ENTIRE AREA MONDAY AFTERNOON THROUGH TUESDAY.
&&
.BEACHES...
05/900 AM
A LARGE LONG-PERIOD WESTERLY SWELL WILL CONTINUE ACROSS THE
COASTAL WATERS THROUGH SUNDAY...GENERATING HIGH SURF CONDITIONS
ALONG WEST FACING BEACHES.
BY MONDAY INTO EARLY TUESDAY...AN EVEN LARGER LONG-PERIOD WEST
SWELL WILL MOVE INTO THE COASTAL WATERS AND SURF CONDITIONS ACROSS
LOCAL BEACHES ARE EXPECTED TO BE EVEN HIGHER. A HIGH SURF ADVISORY
WILL CONTINUE. HOWEVER...THE POTENTIAL EXISTS FOR SURF HEIGHTS TO
EXCEED WARNING LEVELS FOR THE CENTRAL COAST AND WEST FACING
BEACHES OF LA/VENTURA COUNTIES. IN ADDITION TO THE VERY LARGE
SURF...HIGH TIDES IN THE 6 TO 6.5 FOOT RANG COMBINED WITH GUSTY
ONSHORE WINDS AND RAINFALL COULD BRING A THREAT OF MODERATE
COASTAL FLOODING TO THESE SAME LOCATIONS. THE COASTAL FLOOD THREAT
COULD ALSO CONTINUE INTO TUESDAY MORNING NEAR TIME OF HIGH TIDE.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...HIGH SURF ADVISORY IN EFFECT UNTIL 3 PM PST TUESDAY FOR ZONES
34-35-39>41-87. (SEE LAXCFWLOX).
WIND ADVISORY IN EFFECT UNTIL 6 AM PST SUNDAY FOR ZONES
34-35-37-38-51-52. (SEE LAXNPWLOX).
GALE WATCH IN EFFECT FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING FOR ZONE 34. (SEE LAXMWWLOX).
WIND ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO 9 PM PST
SUNDAY FOR ZONES 53-54-59. (SEE LAXNPWLOX).
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 PM PST MONDAY FOR
ZONES 645-670-673-676. (SEE LAXMWWLOX).
SMALL CRAFT ADVISORY IN EFFECT FROM 8 AM SUNDAY TO 3 PM PST
MONDAY FOR ZONES 650-655. (SEE LAXMWWLOX).
&&
$$
PUBLIC...RORKE
AVIATION...HALL
MARINE...30
BEACHES...RAT
SYNOPSIS...BARTLING
WEATHER.GOV/LOSANGELES
[top]
Area Forecast Discussion
National Weather Service Sacramento CA
218 PM PST SAT MAR 5 2016
.SYNOPSIS...
A strong storm system will move through the area through this
evening with heavy rain, strong winds, and localized flooding.
Additional rain, along with heavy snow in the mountains, is on tap
for Sunday, Monday, and late next week.
&&
.DISCUSSION...
Main event is underway with increasing wind and precipitation
across the area. One large area of showers has moved out of the
valley into the foothills and northern Sierra, but another area of
showers presently enhancing to the southwest of the Bay Area will
move into the southern Sacramento and northern San Joaquin Valleys
late this afternoon.
Satellite imagery shows the cold front is now inside of 130W, and
with its current movement, it will move across interior NorCal by
mid to late evening accompanied by very heavy rain and perhaps a
little thunder. Strong ascent and wide swath of deep TPW (in
excess of 1.25 inches) ahead of the front result in extreme water
vapor transport anomalies this evening (> 7 SD on NAEFS mean
IVT!), so heavy rain nearly certain. Will continue flash flood
watches for the burn scars and monitor for possible issuance of
flood advisories this evening as heavier rain develops.
Winds have continued to increase this afternoon. The Fresno to
Medford gradient is now around 15 mbs, and the HRRR forecasts it
to increase to around 19-20 mbs by 02Z as a 992 mb surface low
moves across Siskiyou County. High-res models continue to point
toward the potential for a high impact wind event early this
evening across the Sacramento Valley and extending eastward into
the foothills with 925 mb winds forecast to reach nearly 70 kts
ahead of the cold front. Power outages and tree damage will be
likely.
Snow will develop across the northern Sierra passes late tonight
and continue into Monday. Still looking like good potential for
several feet of snow along the crest through Monday with a foot
or two possible as low as 5000 feet. Main snow impacts will hold
off until midnight as profilers indicate the snow level is still
above 7500 feet. Snow levels will rapidly lower behind the cold
frontal passage late tonight.
Heavier precipitation tapers by 12Z Sunday, then picks up again
later Sunday into Monday as the next wave moves into the area.
Break in the weather looks more likely for Tuesday.
&&
.EXTENDED DISCUSSION (Wednesday THROUGH Saturday)
Upper ridging over the area Wednesday shifts east allowing some
overrunning precip. GFS keeps this precip mainly north of the
forecast area while the EC spreads it over most of the CWA.
Forecast is a blend of these Wednesday.
Models in better agreement Thursday into Friday and advertise
another atmospheric river dropping slowly south through Interior
NorCal. QPF values look to be significant during this period. By
Saturday, forecast confidence lowers as EC returns upper ridging
and drier weather, while the GFS keeps moist cyclonic flow and
showers, along with strong wind, especially in orographically
favored mountains.
&&
&&
.AVIATION...
Frontal system will impact NorCal this evening into Sunday
morning. Expect widespread MVFR/IFR conditions during frontal
passage with local LIFR over mountains. Strong southwest winds
aloft with strong southerly winds in the valley. Wind gusts
ranging 30 to 50 kts...locally higher over ridgetops through at
least 06z. Airport Weather Warnings issued for KRDD and KSCK for
this evening. JBB
&&
.STO Watches/Warnings/Advisories...
Winter Storm Warning until 4 PM PST Monday for West Slope
Northern Sierra Nevada-Western Plumas County/Lassen Park.
Flash Flood Watch through late tonight for Clear Lake/Southern
Lake County-Motherlode-West Slope Northern Sierra Nevada.
Wind Advisory until 10 PM PST this evening for Burney Basin /
Eastern Shasta County-Carquinez Strait and Delta-Central
Sacramento Valley-Clear Lake/Southern Lake County-Motherlode-
Mountains Southwestern Shasta County to Northern Lake County-
Northeast Foothills/Sacramento Valley-Northern Sacramento Valley-
Northern San Joaquin Valley-Shasta Lake Area / Northern Shasta
County-Southern Sacramento Valley.
High Wind Warning until 10 PM PST this evening for Central
Sacramento Valley-Motherlode-Northeast Foothills/Sacramento
Valley-Northern Sacramento Valley-Southern Sacramento Valley.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
949 AM PST SAT MAR 5 2016
...HEAVY RAIN LATER THIS AFTERNOON AND EVENING...
...MODERATE RAIN EVENT SUNDAY NIGHT WITH NEXT FRONT...
.SYNOPSIS...PERIODS OF RAIN...MAINLY LIGHT THIS MORNING. RAIN WILL
THEN INCREASE AND BECOME MODERATE TO HEAVY AFTER 2 PM AS A STRONG
COLD FRONT APPROACHES THE BAY AREA. PERIODS OF HEAVY RAIN THIS
EVENING WITH GUSTY SOUTHERLY WINDS. WIND AND RAIN WILL RAPIDLY
WIND DOWN BEFORE MIDNIGHT. SHOWERS AND ISOLATED THUNDERSTORMS
SUNDAY IN POST FRONTAL ENVIRONMENT. NEXT FRONT ARRIVES SUNDAY
NIGHT WITH ANOTHER ROUND OF MODERATE RAINS. SHOWERS LINGER MONDAY
THEN DRY THROUGH MIDWEEK. CHANCE OF NORTH BAY RAIN BY WEDNESDAY
THEN ALL OF THE BAY AREA AND CENTRAL COAST BY THURSDAY AND FRIDAY.
&&
.DISCUSSION...AS OF 9:00 AM PST SATURDAY...RAIN CONTINUES ACROSS
OUR REGION WITH MANY LOCATIONS BETWEEN 1 AND 3 TENTHS OVER THE
PAST THREE HOURS. KMUX RADAR SHOWS MORE RAIN ON THE WAY ALTHOUGH
LOOKS LIKE A DEFINITE BREAK CAN BE EXPECTED LATE THIS MORNING
(WHICH THE HRRR ALSO INDICATES).
RAIN WILL QUICKLY RETURN THIS AFTERNOON BECOMING MODERATE TO
HEAVY AT TIMES AS A STRONG COLD FRONT ADVANCES TO OUR REGION. WPC
NOW HAS MOST OF OUR AREA IN THE SLIGHT CHANCE FOR EXCESSIVE
RAINFALL AND WITH GUIDANCE STILL SHOWING HEAVY RAIN LATER, DECIDED
TO ISSUE A FLASH FLOOD WATCH FOR OUR ENTIRE AREA. ALSO ISSUED AN
UPDATE TO THE QPF GRIDS BASED OFF LATEST RFC VALUES, HOWEVER
AMOUNTS ARE ONLY SLIGHTLY DIFFERENT COMPARED TO THE PREVIOUS
FORECAST PACKAGE. WINDS STILL ON TRACK SO WILL KEEP THE WIND
ADVISORY AS IS. BOTTOM LINE...PEOPLE THROUGHOUT THE SAN FRANCISCO
AND MONTEREY BAY REGION SHOULD MAKE PREPARATIONS NOW BEFORE THE
STORM HITS LATER TODAY.
OVERALL FORECAST LOOKS TO BE ON TRACK.
.PREVIOUS DISCUSSION...ISSUED A PNS AT 3 AM WITH LATEST 24 HOUR
RAINFALL TOTALS. RADAR SHOWS OVERNIGHT STEADY RAINFALL MOVING
EASTWARD BUT MORE RETURNS STARTING TO DEVELOP WELL OFFSHORE. WERE
STILL IN THE WARM ADVECTION ENVIRONMENT WITH MAINLY LIGHT AND
PERIODIC RAINFALL THROUGH LUNCH TIME TODAY. IR SATELLITE OVER THE
LAST 6 HOURS OR SO IS SHOWING A BAROCLINIC LEAF CLOUD BLOWING UP
OUT NEAR 130W/36N...EVIDENCE OF STRONG INCOMING JET STREAK AND
STRENGTHENING SURFACE COLD FRONTAL BOUNDARY. THIS IS THE FEATURE
THE MODELS HAVE BEEN HONING IN ON NOW FOR NEARLY THE LAST WEEK.
FEATURE WILL QUICKLY APPROACH THE COAST TODAY AND EXPECT MODERATE
RAINS TO START IN EARNEST AROUND 2 PM OR SO OVER MUCH OF THE
GREATER BAY AREA. LOCAL HILLS SUCH AS BIG SUR AND SANTA CRUZ
MOUNTAINS WILL SEE PERIODS OF RAIN THROUGH MOST OF THE DAY.
ANYWAY THE HIGHLY ANTICIPATED FRONTAL PASSAGE SHOULD BE OBVIOUS
FROM ROUGHLY 3 PM TO 8 PM LOCAL TIME WHEN VERY STRONG WINDS AND
HEAVY RAIN OCCUR OVER A SEVERAL HOUR WINDOW OF TIME. DO EXPECT
SOME PREFRONTAL SOUTHERLY WIND GUSTS TO SHOW UP AS EARLY AS LUNCH
TIME AND CURRENT TIMING OF WIND ADVISORY TO START THEN STILL LOOKS
GOOD. SANTA CRUZ MOUNTAINS OFTEN SEE WIND DAMAGE AND LINES DOWN IN
THESE TYPE OF PATTERNS AS SYNOPTIC FLOW AND STRONG SOUTHEAST WINDS
FLOWING OUT OF SALINAS VALLEY FOCUS UP THERE. ANYWAY THE HRRR AND
RAP SHORT TERM MESOSCALE MODELS ARE IN AGREEMENT THAT THE HEAVIEST
RAINS FALL FROM ROUGHLY 4 TO 8 PM THIS EVENING (EARLIEST IN THE
NORTH BAY AND LATEST IN MONTEREY BAY REGION). STORM TOTALS FROM
NOW THROUGH ABOUT 10 PM TONIGHT SHOULD BRING 1-2 INCHES TO THE
LOWER ELEVATIONS WITH 2-5 INCHES FOR THE NORTH BAY/SANTA CRUZ AND
SANTA LUCIA HILLS. (USUAL DRY SPOTS IN THE SALINAS AND EAST BAY
VALLEYS WILL BE UNDER AN INCH). THIS STORM WILL CAUSE ISSUES
TONIGHT THROUGHOUT THE BAY AREA WITH TRAFFIC...LOCALIZED FLOODING
DUE TO THE HEAVY RAIN RATES OVER A SHORT WINDOW OF TIME AND
ASSOCIATED WIND DAMAGE ISSUES.
A DISTINCT LULL IN THE ACTION WILL OCCUR AFTER MIDNIGHT BEHIND THE
FRONT WITH ONLY SOME LINGERING SHOWERS AND MUCH LIGHTER SW WINDS.
SHOWER AND POST FRONTAL T-STORMS POSSIBLE ON SUNDAY BUT PARTLY
CLOUDY SKIES WILL PREVAIL FOR MANY AREAS SOUTH OF SAN FRANCISCO ON
SUNDAY. NEXT SYSTEM APPROACHING WILL BRING GENTLE WARM ADVECTION
RAINS TO THE NORTH BAY BY SUNDAY AFTERNOON.
THEN ON SUNDAY NIGHT POTENT SHORTWAVE WITH MUCH COLDER AIR ALOFT
WILL PASS FROM NW TO SE ACROSS THE DISTRICT. ANOTHER ROUND OF SOME
HEAVY RAIN SHOWERS WITH POSSIBLE T-STORMS WILL OCCUR. RAIN TOTALS
WILL BE LESS WITH THIS SYSTEM BUT SOME LOCALIZED HEAVY RAINFALL
SHOULD BE EXPECTED. LOOKS LIKE THE BULK OF THE HEAVY RAIN IS DONE
BY 12Z MONDAY WITH ONLY SOME LINGERING RAINS SHOWERS BY 15Z MONDAY
FOR THE MORNING COMMUTE. HOWEVER EVEN A WET START TO THE COMMUTE
IS OFTEN ENOUGH TO THROW THINGS INTO DISARRAY TO START OUT THE
WORK WEEK. SIMILAR TO SUNDAY...SHOWERS CHANCES WILL LINGER MONDAY
BUT BE ON THE DECREASE THROUGH THE DAY.
LOOKS DRY MONDAY NIGHT AND TUESDAY. LATEST ECMWF HAS TRENDED
WETTER BY WEDS FOR THE NORTH BAY WITH SOME WARM FRONTAL LIGHT RAIN
CHANCES. MORE ORGANIZED COLD FRONT THEN ARRIVES LATER THURSDAY
INTO FRIDAY. WILL HONE IN ON THOSE DETAILS AFTER WE GET THROUGH
THE WEEKEND SYSTEMS BUT THE STORMS LATER NEXT WEEK LOOK MODERATE
IN STRENGTH/INTENSITY.
&&
.AVIATION...AS OF 9:49 AM PST SATURDAY...A STRONG COLD FRONT WILL
MOVE ACROSS THE AREA THIS EVENING. DETERIORATING WX CONDITIONS
TODAY WITH MODERATE-HEAVY RAIN AND STRONG S-SE WINDS EXPECTED UP
TO THE FRONTAL PASSAGE THIS EVENING. SHOWERY COLDER MORE UNSTABLE
AIR ARRIVES LATE TONIGHT AND SUNDAY.
VICINITY OF KSFO...AIRPORT WEATHER WARNING ISSUED FOR STRONG AND
GUSTY S-SE WINDS. MVFR CIGS. RAIN.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS. STRONG AND GUSTY SOUTHERLY
WINDS DEVELOPING TODAY. RAIN.
&&
.BEACHES...AS OF 5:30 AM PST SATURDAY...A HIGH SURF ADVISORY
BEGINS 10 PM TONIGHT AND LASTS INTO TUESDAY MORNING. WESTERLY
SWELL WILL BE PEAKING CLOSE TO 20 FEET WITH 14 SECOND SWELL
PERIODS FROM LATE SUNDAY NIGHT TO MONDAY NIGHT. IF FUTURE WAVE
MODEL FORECASTS TREND STEADY OR HIGHER WITH THE PEAK OF THIS SWELL
TRAIN THEN THE ADVISORY MAY NEED TO BE UPGRADED TO A HIGH SURF
WARNING AT A LATER POINT IN TIME. PLEASE STAY TUNED.
&&
.MARINE...AS OF 8:27 AM PST SATURDAY...SOUTHERLY WINDS WILL
BECOME STRONG AND GUSTY TODAY AS A COLD FRONT APPROACHES THE AREA.
GALE FORCE WINDS ARE EXPECTED OVER THE WATERS THIS AFTERNOON AND
TONIGHT. A LARGE WESTERLY SWELL WILL ARRIVE TONIGHT AND PERSIST
THROUGH EARLY TUESDAY MORNING.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...WIND ADVISORY...ALL LOCATIONS TODAY AND THIS EVENING
FLASH FLOOD WATCH...ALL LOCATIONS TODAY AND THIS EVENING
SCA...MRY BAY FROM 10 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 10 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 10 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 10 AM
GLW...MRY BAY FROM 4 PM
GLW...PIGEON PT TO PT PINOS 0-10 NM FROM 4 PM
GLW...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 4 PM
GLW...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 4 PM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 10 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 10 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 10 AM
GLW...PT ARENA TO PT REYES 0-10 NM FROM 10 AM
GLW...PT REYES TO PIGEON PT 0-10 NM FROM 10 AM
GLW...PT ARENA TO PIGEON PT 10-60 NM FROM 10 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR
SCA...SF BAY UNTIL NOON
GLW...SF BAY FROM NOON
&&
$$
PUBLIC FORECAST: BELL/R_WALBRUN
AVIATION: SIMS
MARINE: SIMS
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AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
909 AM PST SAT MAR 5 2016
...HEAVY RAIN LATER THIS AFTERNOON AND EVENING...
...MODERATE RAIN EVENT SUNDAY NIGHT WITH NEXT FRONT...
.SYNOPSIS...PERIODS OF RAIN...MAINLY LIGHT THIS MORNING. RAIN WILL
THEN INCREASE AND BECOME MODERATE TO HEAVY AFTER 2 PM AS A STRONG
COLD FRONT APPROACHES THE BAY AREA. PERIODS OF HEAVY RAIN THIS
EVENING WITH GUSTY SOUTHERLY WINDS. WIND AND RAIN WILL RAPIDLY
WIND DOWN BEFORE MIDNIGHT. SHOWERS AND ISOLATED THUNDERSTORMS
SUNDAY IN POST FRONTAL ENVIRONMENT. NEXT FRONT ARRIVES SUNDAY
NIGHT WITH ANOTHER ROUND OF MODERATE RAINS. SHOWERS LINGER MONDAY
THEN DRY THROUGH MIDWEEK. CHANCE OF NORTH BAY RAIN BY WEDNESDAY
THEN ALL OF THE BAY AREA AND CENTRAL COAST BY THURSDAY AND FRIDAY.
&&
.DISCUSSION...AS OF 9:00 AM PST SATURDAY...RAIN CONTINUES ACROSS
OUR REGION WITH MANY LOCATIONS BETWEEN 1 AND 3 TENTHS OVER THE
PAST THREE HOURS. KMUX RADAR SHOWS MORE RAIN ON THE WAY ALTHOUGH
LOOKS LIKE A DEFINITE BREAK CAN BE EXPECTED LATE THIS MORNING
(WHICH THE HRRR ALSO INDICATES).
RAIN WILL QUICKLY RETURN THIS AFTERNOON BECOMING MODERATE TO
HEAVY AT TIMES AS A STRONG COLD FRONT ADVANCES TO OUR REGION. WPC
NOW HAS MOST OF OUR AREA IN THE SLIGHT CHANCE FOR EXCESSIVE
RAINFALL AND WITH GUIDANCE STILL SHOWING HEAVY RAIN LATER, DECIDED
TO ISSUE A FLASH FLOOD WATCH FOR OUR ENTIRE AREA. ALSO ISSUED AN
UPDATE TO THE QPF GRIDS BASED OFF LATEST RFC VALUES, HOWEVER
AMOUNTS ARE ONLY SLIGHTLY DIFFERENT COMPARED TO THE PREVIOUS
FORECAST PACKAGE. WINDS STILL ON TRACK SO WILL KEEP THE WIND
ADVISORY AS IS. BOTTOM LINE...PEOPLE THROUGHOUT THE SAN FRANCISCO
AND MONTEREY BAY REGION SHOULD MAKE PREPARATIONS NOW BEFORE THE
STORM HITS LATER TODAY.
OVERALL FORECAST LOOKS TO BE ON TRACK.
.PREVIOUS DISCUSSION...ISSUED A PNS AT 3 AM WITH LATEST 24 HOUR
RAINFALL TOTALS. RADAR SHOWS OVERNIGHT STEADY RAINFALL MOVING
EASTWARD BUT MORE RETURNS STARTING TO DEVELOP WELL OFFSHORE. WERE
STILL IN THE WARM ADVECTION ENVIRONMENT WITH MAINLY LIGHT AND
PERIODIC RAINFALL THROUGH LUNCH TIME TODAY. IR SATELLITE OVER THE
LAST 6 HOURS OR SO IS SHOWING A BAROCLINIC LEAF CLOUD BLOWING UP
OUT NEAR 130W/36N...EVIDENCE OF STRONG INCOMING JET STREAK AND
STRENGTHENING SURFACE COLD FRONTAL BOUNDARY. THIS IS THE FEATURE
THE MODELS HAVE BEEN HONING IN ON NOW FOR NEARLY THE LAST WEEK.
FEATURE WILL QUICKLY APPROACH THE COAST TODAY AND EXPECT MODERATE
RAINS TO START IN EARNEST AROUND 2 PM OR SO OVER MUCH OF THE
GREATER BAY AREA. LOCAL HILLS SUCH AS BIG SUR AND SANTA CRUZ
MOUNTAINS WILL SEE PERIODS OF RAIN THROUGH MOST OF THE DAY.
ANYWAY THE HIGHLY ANTICIPATED FRONTAL PASSAGE SHOULD BE OBVIOUS
FROM ROUGHLY 3 PM TO 8 PM LOCAL TIME WHEN VERY STRONG WINDS AND
HEAVY RAIN OCCUR OVER A SEVERAL HOUR WINDOW OF TIME. DO EXPECT
SOME PREFRONTAL SOUTHERLY WIND GUSTS TO SHOW UP AS EARLY AS LUNCH
TIME AND CURRENT TIMING OF WIND ADVISORY TO START THEN STILL LOOKS
GOOD. SANTA CRUZ MOUNTAINS OFTEN SEE WIND DAMAGE AND LINES DOWN IN
THESE TYPE OF PATTERNS AS SYNOPTIC FLOW AND STRONG SOUTHEAST WINDS
FLOWING OUT OF SALINAS VALLEY FOCUS UP THERE. ANYWAY THE HRRR AND
RAP SHORT TERM MESOSCALE MODELS ARE IN AGREEMENT THAT THE HEAVIEST
RAINS FALL FROM ROUGHLY 4 TO 8 PM THIS EVENING (EARLIEST IN THE
NORTH BAY AND LATEST IN MONTEREY BAY REGION). STORM TOTALS FROM
NOW THROUGH ABOUT 10 PM TONIGHT SHOULD BRING 1-2 INCHES TO THE
LOWER ELEVATIONS WITH 2-5 INCHES FOR THE NORTH BAY/SANTA CRUZ AND
SANTA LUCIA HILLS. (USUAL DRY SPOTS IN THE SALINAS AND EAST BAY
VALLEYS WILL BE UNDER AN INCH). THIS STORM WILL CAUSE ISSUES
TONIGHT THROUGHOUT THE BAY AREA WITH TRAFFIC...LOCALIZED FLOODING
DUE TO THE HEAVY RAIN RATES OVER A SHORT WINDOW OF TIME AND
ASSOCIATED WIND DAMAGE ISSUES.
A DISTINCT LULL IN THE ACTION WILL OCCUR AFTER MIDNIGHT BEHIND THE
FRONT WITH ONLY SOME LINGERING SHOWERS AND MUCH LIGHTER SW WINDS.
SHOWER AND POST FRONTAL T-STORMS POSSIBLE ON SUNDAY BUT PARTLY
CLOUDY SKIES WILL PREVAIL FOR MANY AREAS SOUTH OF SAN FRANCISCO ON
SUNDAY. NEXT SYSTEM APPROACHING WILL BRING GENTLE WARM ADVECTION
RAINS TO THE NORTH BAY BY SUNDAY AFTERNOON.
THEN ON SUNDAY NIGHT POTENT SHORTWAVE WITH MUCH COLDER AIR ALOFT
WILL PASS FROM NW TO SE ACROSS THE DISTRICT. ANOTHER ROUND OF SOME
HEAVY RAIN SHOWERS WITH POSSIBLE T-STORMS WILL OCCUR. RAIN TOTALS
WILL BE LESS WITH THIS SYSTEM BUT SOME LOCALIZED HEAVY RAINFALL
SHOULD BE EXPECTED. LOOKS LIKE THE BULK OF THE HEAVY RAIN IS DONE
BY 12Z MONDAY WITH ONLY SOME LINGERING RAINS SHOWERS BY 15Z MONDAY
FOR THE MORNING COMMUTE. HOWEVER EVEN A WET START TO THE COMMUTE
IS OFTEN ENOUGH TO THROW THINGS INTO DISARRAY TO START OUT THE
WORK WEEK. SIMILAR TO SUNDAY...SHOWERS CHANCES WILL LINGER MONDAY
BUT BE ON THE DECREASE THROUGH THE DAY.
LOOKS DRY MONDAY NIGHT AND TUESDAY. LATEST ECMWF HAS TRENDED
WETTER BY WEDS FOR THE NORTH BAY WITH SOME WARM FRONTAL LIGHT RAIN
CHANCES. MORE ORGANIZED COLD FRONT THEN ARRIVES LATER THURSDAY
INTO FRIDAY. WILL HONE IN ON THOSE DETAILS AFTER WE GET THROUGH
THE WEEKEND SYSTEMS BUT THE STORMS LATER NEXT WEEK LOOK MODERATE
IN STRENGTH/INTENSITY.
&&
.AVIATION...AS OF 5:44 AM PST SATURDAY...A STRONG COLD FRONT WILL
SWEEP EAST OVER THE AREA THIS EVENING. THIS FRONTAL PASSAGE HAS
THE POTENTIAL TO BE THE STRONGEST WE`VE SEEN THIS WINTER SEASON.
DETERIORATING WX CONDITIONS TODAY WITH MODERATE-HEAVY RAIN AND
HEAVY S-SE WIND COMBINED UP TO THE FRONTAL PASSAGE THIS EVENING.
WORTH NOTING PRE-FRONTAL S-SE WINDS OFTEN CAUSES A RAIN SHADOW FOR
PLACES LIKE THE SOUTH BAY AND THE MONTEREY PENINSULA THUS THE RAIN
MAY AT TIMES BECOME MORE PERIODIC TODAY IN PLACES THAT ARE IN THE
LEE OF HIGHER TERRAIN. SHOWERY COLDER MORE UNSTABLE AIR ARRIVES
LATE TONIGHT AND SUNDAY.
VICINITY OF KSFO...AIRPORT WEATHER WARNING ISSUED FOR STRONG AND
GUSTY S-SE WINDS. MVFR CIGS. RAIN.
SFO BRIDGE APPROACH...SIMILAR TO KSFO.
MONTEREY BAY AREA TERMINALS...MVFR CIGS. STRONG AND GUSTY SOUTHERLY
WINDS DEVELOPING TODAY. RAIN.
&&
.BEACHES...AS OF 5:30 AM PST SATURDAY...A HIGH SURF ADVISORY
BEGINS 10 PM TONIGHT AND LASTS INTO TUESDAY MORNING. WESTERLY
SWELL WILL BE PEAKING CLOSE TO 20 FEET WITH 14 SECOND SWELL
PERIODS FROM LATE SUNDAY NIGHT TO MONDAY NIGHT. IF FUTURE WAVE
MODEL FORECASTS TREND STEADY OR HIGHER WITH THE PEAK OF THIS SWELL
TRAIN THEN THE ADVISORY MAY NEED TO BE UPGRADED TO A HIGH SURF
WARNING AT A LATER POINT IN TIME. PLEASE STAY TUNED.
&&
.MARINE...AS OF 08:53 AM PST SATURDAY...SOUTHERLY WINDS WILL
BECOME STRONG AND GUSTY TODAY AS A COLD FRONT APPROACHES THE AREA.
GALE FORCE WINDS ARE EXPECTED OVER THE WATERS THIS AFTERNOON AND
TONIGHT. A LARGE WESTERLY SWELL WILL ARRIVE TONIGHT AND PERSIST
THROUGH EARLY TUESDAY MORNING.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
.TDAY...WIND ADVISORY...ALL LOCATIONS TODAY AND THIS EVENING
FLASH FLOOD WATCH...ALL LOCATIONS TODAY AND THIS EVENING
SCA...MRY BAY FROM 10 AM
SCA...PIGEON PT TO PT PINOS 0-10 NM FROM 10 AM
SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 10 AM
SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 10 AM
GLW...MRY BAY FROM 4 PM
GLW...PIGEON PT TO PT PINOS 0-10 NM FROM 4 PM
GLW...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM FROM 4 PM
GLW...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 4 PM
SCA...PT ARENA TO PT REYES 0-10 NM UNTIL 10 AM
SCA...PT REYES TO PIGEON PT 0-10 NM UNTIL 10 AM
SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 10 AM
GLW...PT ARENA TO PT REYES 0-10 NM FROM 10 AM
GLW...PT REYES TO PIGEON PT 0-10 NM FROM 10 AM
GLW...PT ARENA TO PIGEON PT 10-60 NM FROM 10 AM
SCA...ROUGH BAR ADVISORY FOR SF BAR
SCA...SF BAY UNTIL NOON
GLW...SF BAY FROM NOON
&&
$$
PUBLIC FORECAST: BELL/R_WALBRUN
AVIATION: CANEPA
MARINE: SIMS
VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO
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AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
259 PM CST SAT MAR 5 2016
.SHORT TERM...(Tonight)
ISSUED AT 259 PM CST SAT MAR 5 2016
Despite passage of a short-wave trough and its associated cold
front, clouds continue to blanket central Illinois this afternoon.
In fact, 20z/2pm visible satellite imagery shows continuous cloud
cover upstream into Wisconsin and the eastern half of Iowa as well.
Based on the trajectory of the clouds, the KILX CWA will remain on
the southwest periphery of the cloud shield through at least early
evening. HRRR has been consistently showing the clouds partially
dissipating from the W/SW toward sunset, resulting in mostly clear
skies across much of the area by mid to late evening. Think this
may be a bit too aggressive with the clearing, so have slowed trends
from previous forecasts. Have started the evening with mostly
cloudy skies everywhere except across the far southwest around
Jacksonville where partly to mostly clear conditions will prevail.
As per the latest HRRR, have then cleared things out from west to
east through the evening, but have maintained mostly cloudy skies
northeast of I-74 until well after midnight. Due to the clearing
skies and diminishing winds, have undercut MAV guidance numbers by a
couple of degrees, with frosty overnight lows in the middle to upper
20s.
&&
.LONG TERM...(Sunday through Saturday)
ISSUED AT 259 PM CST SAT MAR 5 2016
Mild temperatures and wet weather will be the primary features for
much of the upcoming forecast period through next Saturday.
For Sunday, brisk southerly winds around 15 mph and gusts around 25
mph will set up by afternoon west of I-57 as a corridor of strong
moist southwesterly flow sets up over the Plains. This will initiate
showers and a few thunderstorms, potentially creeping eastward into
west-central IL Sunday night. Highs should reach the mid 50s to
around 60 degrees in Springfield and Jacksonville. Mild lows in the
mid 40s expected Sunday night as precipitable water around 1 inch,
or approaching 99th percentile for this time of year, plumes over
central IL.
On Monday, southerly winds expected to increase to 15-20 mph and
gust to 25-30 mph. High temperatures should reach the mid 60s as
warm advection continues, and rich precipitable water continues to
stream over Illinois. Still, weak forcing appears it will result in
modest precipitation chances and amounts, mainly I-72 northward.
The moisture plume looks to remain in the vicinity through midweek
as a frontal boundary lingers just to the northwest, and a series of
disturbances track along the front bringing periods of heavier rain.
Some uncertainty remain in the location of the front through midweek
and this will modulate the exact timing and location of
precipitation through midweek, however likely to categorical (80%+)
chance of precipitation included in the forecast for Tuesday night
through Wednesday night, and current precipitation amounts 2-2.5
inches I-72 southward expected through this period, with 0.5 to 2.0
inches to the north. Instability pattern indicates occasional
thunderstorms a possibility. A hydrologic outlook remains in effect
to address the heavy rain concern during this period. Highs through
midweek expected to remain mild, from around 60 to 65 degrees.
Next weekend...a cut-off low that should be meanering over Mexico
midweek is progged to eject northeast toward central IL.
Unfortunately, the timing and track of this feature is highly
uncertain as evidenced by a variety of differing model and ensemble
solutions available at this time. This feature will have impacts on
the position of the frontal boundary, temperatures, and
precipitation for central IL. With the front position still a
significant question, PoP`s generally remain in place over most of
the forecast area into Saturday. High temperatures forecast from
around 60 to 65, but this will be subject to change.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1134 AM CST SAT MAR 5 2016
MVFR ceilings continue to spill southward into central Illinois
behind a departing cold front late this morning. While visible
satellite imagery shows plenty of clouds upstream across
Iowa/Wisconsin, there are also a few holes developing in the
overcast. HRRR has consistently suggested the cloud deck would
begin to erode this afternoon, with any appreciable clearing
holding off until evening. 12z NAM forecast soundings support this
as well, with skies clearing at KSPI around 00z...then further
northeast to KCMI by 03z. Skies will then remain mostly clear
through the night before WAA on the back side of retreating high
pressure brings increasing mid-level clouds Sunday morning. NAM
shows rapidly increasing moisture within the 12000 to 15000ft
layer across the western half of the area after 14z, so have
included a broken mid deck at all sites except KDEC and KCMI.
Winds will initially be strong/gusty from the northwest this
afternoon, then will become light/variable tonight as high
pressure drifts overhead.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Onton
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1134 AM CST SAT MAR 5 2016
.UPDATE...
ISSUED AT 1035 AM CST SAT MAR 5 2016
Weak cold front is currently passing through central Illinois,
with 16z/10am obs showing it approaching the Indiana border. No
precip is occurring with the front: however, quite a bit of low
cloud cover is spilling southward in its wake. Latest satellite
imagery shows ample clouds upstream across Iowa, Wisconsin, and
Minnesota. Based on trajectory of clouds, central Illinois will
remain on the S/SW edge of the cloud shield today. Most high-res
guidance is suggesting the clouds will begin to erode this
afternoon, resulting in partial clearing across the S/SW KILX
CWA. Elsewhere around the area, skies will remain mostly cloudy
throughout the day. Northwesterly winds will gust to between 20
and 30mph behind the front, while afternoon high temperatures
reach the middle to upper 40s across much of the area. The
exception will be south of I-70 around Flora and Olney where
additional sunshine will boost highs into the lower 50s.
&&
.SHORT TERM...(Today)
ISSUED AT 241 AM CST SAT MAR 5 2016
Patchy fog will affect central Illinois ahead of an advancing
cold front early this morning. The fog will clear by mid-morning as
cold front departs into Indiana by 11 am. Little to no precipitation
is expected with the frontal passage in central Illinois, except for
possibly a few sprinkles in areas northeast of Champaign to
Danville. Winds will shift from southwest to northwest behind the
front, and become breezy with gusts to 25 mph at times later this
morning and this afternoon.
The latest HRRR and RAP guidance are pointing towards enough
residual low level moisture behind the front for mostly cloudy skies
to linger through at least mid-afternoon. Breaks will eventually
develop in the cloud layer due to turbulent mixing of dry mid-level
air toward the surface. Areas southwest of Springfield to Mattoon
will have the best chances of seeing sunshine earlier, but even
northeast areas should see sunshine break through later this
afternoon. Even limited late afternoon sunshine should help high
temperatures reach the mid 40s north of I-74, with lower 50s for
areas from Jacksonville to Effingham to Lawrenceville.
.LONG TERM...(Tonight through Friday)
ISSUED AT 241 AM CST SAT MAR 5 2016
Mild and wet period shaping up for much of the upcoming week, as
upper flow finally trends more toward the southwest. Main issue will
be with the rains, as a frontal boundary will be draped over the
state part of the time, and will limit some of the rainfall north of
it around midweek.
High pressure will quickly pass through the Midwest tonight, and
southerly winds will be in place by Sunday morning and become a bit
gusty. This will bring temperatures well into the 50s, with some 60
degree readings possible over the southwest CWA. Some WAA-type
precip expected to develop by afternoon west of the Illinois border,
but forecast soundings in our area quite parched below 700 mb until
evening, and thus will keep the daytime hours dry albeit with
increasing clouds. Have limited mentionable PoP`s Sunday night to
west of I-55, with most of the energy tracking into northwest
Illinois.
On Monday, southerly winds expected to gust from 25-30 mph, pushing
temperatures well into the 60s. During this time, an upper trough
will be digging southward along the California coast, closing off a
low over the Baja. Nice moisture surge coming northward from the
Gulf of Mexico will combine with a wave/front in the northern stream
to gradually increase rain chances from west to east across the
state. Reasonable agreement among the models through about Tuesday
evening with the cold front being just to our northwest. Waves of
low pressure will surge northeast along the front bringing periods
of heavier rain, but how far south the front makes it first will be
key. The ECMWF is slowest in exiting the rain (not until Thursday
evening over the southeast CWA), while the GFS and Canadian show
periodic surges of rain until Thursday morning. Went with
categorical PoP`s (80%) for most areas east of I-55 Tuesday night
through Wednesday night. WPC progs and blended model guidance
suggesting potential for 3-4 inches of rain through the week in this
area, subject to the oscillations of the front. Hydrologic Outlook
product is being used to address this heavy rain concern for the
time being.
The upper low will only slowly drift through northern Mexico, cut
off from the northern flow through much of the week. Late in the
period, the GFS and ECMWF show this low finally ejecting northeast,
although the GFS is much faster in bringing the frontal boundary
back north. With the front position still a significant question,
PoP`s generally remain in place over most of the forecast area into
Friday. Temperatures north of the front will cool a bit mid week,
but still be mid-upper 50s for highs.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1134 AM CST SAT MAR 5 2016
MVFR ceilings continue to spill southward into central Illinois
behind a departing cold front late this morning. While visible
satellite imagery shows plenty of clouds upstream across
Iowa/Wisconsin, there are also a few holes developing in the
overcast. HRRR has consistently suggested the cloud deck would
begin to erode this afternoon, with any appreciable clearing
holding off until evening. 12z NAM forecast soundings support this
as well, with skies clearing at KSPI around 00z...then further
northeast to KCMI by 03z. Skies will then remain mostly clear
through the night before WAA on the back side of retreating high
pressure brings increasing mid-level clouds Sunday morning. NAM
shows rapidly increasing moisture within the 12000 to 15000ft
layer across the western half of the area after 14z, so have
included a broken mid deck at all sites except KDEC and KCMI.
Winds will initially be strong/gusty from the northwest this
afternoon, then will become light/variable tonight as high
pressure drifts overhead.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Shimon
LONG TERM...Geelhart
AVIATION...Barnes
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1035 AM CST SAT MAR 5 2016
.UPDATE...
ISSUED AT 1035 AM CST SAT MAR 5 2016
Weak cold front is currently passing through central Illinois,
with 16z/10am obs showing it approaching the Indiana border. No
precip is occurring with the front: however, quite a bit of low
cloud cover is spilling southward in its wake. Latest satellite
imagery shows ample clouds upstream across Iowa, Wisconsin, and
Minnesota. Based on trajectory of clouds, central Illinois will
remain on the S/SW edge of the cloud shield today. Most high-res
guidance is suggesting the clouds will begin to erode this
afternoon, resutling in partial clearing across the S/SW KILX CWA.
Elsewhere around the area, skies will remain mostly cloudy
throughout the day. Northwesterly winds will gust to between 20
and 30mph behind the front, while afternoon high temperatures
reach the middle to upper 40s across much of the area. The
exception will be south of I-70 around Flora and Olney where
additional sunshine will boost highs into the lower 50s.
&&
.SHORT TERM...(Today)
ISSUED AT 241 AM CST SAT MAR 5 2016
Patchy fog will affect central Illinois ahead of an advancing
cold front early this morning. The fog will clear by mid-morning as
cold front departs into Indiana by 11 am. Little to no precipitation
is expected with the frontal passage in central Illinois, except for
possibly a few sprinkles in areas northeast of Champaign to
Danville. Winds will shift from southwest to northwest behind the
front, and become breezy with gusts to 25 mph at times later this
morning and this afternoon.
The latest HRRR and RAP guidance are pointing towards enough
residual low level moisture behind the front for mostly cloudy skies
to linger through at least mid-afternoon. Breaks will eventually
develop in the cloud layer due to turbulent mixing of dry mid-level
air toward the surface. Areas southwest of Springfield to Mattoon
will have the best chances of seeing sunshine earlier, but even
northeast areas should see sunshine break through later this
afternoon. Even limited late afternoon sunshine should help high
temperatures reach the mid 40s north of I-74, with lower 50s for
areas from Jacksonville to Effingham to Lawrenceville.
.LONG TERM...(Tonight through Friday)
ISSUED AT 241 AM CST SAT MAR 5 2016
Mild and wet period shaping up for much of the upcoming week, as
upper flow finally trends more toward the southwest. Main issue will
be with the rains, as a frontal boundary will be draped over the
state part of the time, and will limit some of the rainfall north of
it around midweek.
High pressure will quickly pass through the Midwest tonight, and
southerly winds will be in place by Sunday morning and become a bit
gusty. This will bring temperatures well into the 50s, with some 60
degree readings possible over the southwest CWA. Some WAA-type
precip expected to develop by afternoon west of the Illinois border,
but forecast soundings in our area quite parched below 700 mb until
evening, and thus will keep the daytime hours dry albeit with
increasing clouds. Have limited mentionable PoP`s Sunday night to
west of I-55, with most of the energy tracking into northwest
Illinois.
On Monday, southerly winds expected to gust from 25-30 mph, pushing
temperatures well into the 60s. During this time, an upper trough
will be digging southward along the California coast, closing off a
low over the Baja. Nice moisture surge coming northward from the
Gulf of Mexico will combine with a wave/front in the northern stream
to gradually increase rain chances from west to east across the
state. Reasonable agreement among the models through about Tuesday
evening with the cold front being just to our northwest. Waves of
low pressure will surge northeast along the front bringing periods
of heavier rain, but how far south the front makes it first will be
key. The ECMWF is slowest in exiting the rain (not until Thursday
evening over the southeast CWA), while the GFS and Canadian show
periodic surges of rain until Thursday morning. Went with
categorical PoP`s (80%) for most areas east of I-55 Tuesday night
through Wednesday night. WPC progs and blended model guidance
suggesting potential for 3-4 inches of rain through the week in this
area, subject to the oscillations of the front. Hydrologic Outlook
product is being used to address this heavy rain concern for the
time being.
The upper low will only slowly drift through northern Mexico, cut
off from the northern flow through much of the week. Late in the
period, the GFS and ECMWF show this low finally ejecting northeast,
although the GFS is much faster in bringing the frontal boundary
back north. With the front position still a significant question,
PoP`s generally remain in place over most of the forecast area into
Friday. Temperatures north of the front will cool a bit mid week,
but still be mid-upper 50s for highs.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 600 AM CST SAT MAR 5 2016
A cold front, currently passing on a line from Galesburg to
Quincy, will continue to track east across our area this morning.
Forecast soundings and last few runs of the HRRR model correctly
depicted the IFR/LIFR ceilings in over our eastern terminals of
CMI, BMI, and DEC. PIA also dropped down to VLIFR vis and IFR cig.
Conditions will improve to VFR at all the terminal sites as the
cold front passes between 13z and 16z.
Satellite images show a region of high MVFR and VFR clouds
rotating into NW IL. They are poised to affect all of our terminal
sites later this morning and early this afternoon, with less
coverage for the southern TAF sites of SPI and DEC. Turbulent
mixing of dry mid level air should help to create breaks in cloud
cover as the afternoon progresses.
The winds are the other issue today, with southwest winds becoming
light as the cold front passes, then increasing out of the
northwest shortly after FROPA. Sustained winds will become 12-16kt
with gusts to 23kt at times late this morning and early this
afternoon. Pressure rises will weaken later this afternoon, with
gusts diminishing by sunset.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Barnes
SHORT TERM...Shimon
LONG TERM...Geelhart
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS JACKSON KY
302 PM EST SAT MAR 5 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 220 PM EST SAT MAR 5 2016
18Z SFC ANALYSIS SHOWS LOW PRESSURE MOVING SOUTH THROUGH EASTERN
KENTUCKY ON ITS TREK TO THE SOUTHEAST COAST. THIS IS PUSHING A
FAIRLY LARGE BAND OF SCATTERED TO NUMEROUS SHOWERS THROUGH THE CWA
WITH GENERALLY A TENTH TO TWO TENTHS OF AN INCH OF RAIN EXPECTED.
EARLIER...THIS LOW HELPED TO BREAK UP THE LOW CLOUDS AND FOG
RELEASING THE AREA FROM CHILLY TEMPERATURES IN THE LOWER AND
MIDDLE 30S. CURRENTLY...READINGS HAVE MADE IT INTO THE LOW 40S
NORTH AND THE LOWER 50S SOUTH ON SOUTH TO SOUTHWEST WINDS.
DEWPOINTS...MEANWHILE...HAVE ALSO CLIMBED WITH THE UPPER 30S AND
40S MOST COMMON AS THE RAIN STARTS TO MOVE IN.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST AS A COMPACT WAVE STRENGTHENS AND MOVES
THROUGH THE SOUTHERN APPALACHIANS...TO THE SOUTHEAST COAST LATER
TODAY AND INTO TONIGHT. THIS SHARP LITTLE FEATURE WILL BE FOLLOWED
BY AN EQUALLY DISTINCT RIDGE BUILDING INTO KENTUCKY FROM THE
SOUTHERN PLAINS. THIS RIDGE PLANTS ITSELF FIRMLY OVER THE AREA ON
SUNDAY...BUILDING INTO MONDAY AS IT STARTS TO BE PUMPED UP DUE TO
ITS POSITION DOWNSTREAM OF A LARGE DIGGING WEST COAST TROUGH. LOOK
FOR THE RIDGE TO KEEP ANY MID LEVEL WAVES OF ENERGY TO THE NORTH
OF THE AREA KEEPING THE WX QUIET. GIVEN THE MODEL AGREEMENT AND
MAINLY JUST NEAR TERM WEATHER CONCERNS...HAVE FAVORED A GENERAL
MODEL BLEND WITH STRONG LEAN TOWARD THE HRRR AND NAM12
SOLUTIONS.
SENSIBLE WEATHER WILL FEATURE A RELATIVELY WEAK LOW PRESSURE SFC
WAVE PASSING THROUGH EAST KENTUCKY WITH BULK OF THE SHOWERS
MOVING THROUGH THIS AFTERNOON AND GRADUALLY DIMINISHING INTO THE
EVENING FROM NORTHWEST TO SOUTHEAST. COOLER AIR DOES FOLLOW THIS
LOW BUT NOT ENOUGH TO WORRY ABOUT ANY SNOW MIXING IN BEFORE THE
LAST OF THE PCPN DEPARTS. OF A LARGER CONCERN WILL BE THE
POTENTIAL FOR FOG DEVELOPING AGAIN TONIGHT. GIVEN THE AMPLE LOW
LEVEL MOISTURE LEFT BEHIND AROUND AND ANTICIPATED SUBSIDENCE
INVERSION HAVE HIT THE FOG RATHER HARD IN THE GRIDS WITH SOME
AREAS HAVING SOME DENSE FOG. RIDGES MAY SEE LOW VISIBILITIES...AS
WELL...WITH THE LOW CLOUDS SETTLING IN AFTER MIDNIGHT. THIS WILL
ALL CLEAR OUT FAIRLY QUICKLY ON SUNDAY...THOUGH...WITH SUNSHINE
RETURNING AND SOUTHERLY WINDS HELPING TO BRING TEMPS BACK INTO THE
LOWER AND MIDDLE 50S BY AFTERNOON...FOR MOST PLACES. HIGH PRESSURE
MOVING OFF TO THE EAST WILL LIKELY SET THE STAGE FOR A DECENT
RIDGE TO VALLEY TEMPERATURE SPLIT SUNDAY NIGHT INTO MONDAY
MORNING UNDER MOSTLY CLEAR SKIES AND LIGHT WINDS. ALSO...WOULD
ANTICIPATE SOME VALLEY FOG DEVELOPING LATE SUNDAY NIGHT THROUGH
DAWN MONDAY.
USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WIND GRIDS
THROUGH THE NIGHT BEFORE FAVORING THE SUPERBLEND THEREAFTER. MADE
THE MOST SIGNIFICANT CHANGES TO THE T GRIDS ON SUNDAY NIGHT TO
ACCOUNT FOR THE ANTICIPATED RIDGE AND VALLEY DISTINCTIONS. AS FOR
POP...ENDED UP CLOSEST TO THE HIGHER MET VALUES INTO THE EVENING
BEFORE NEARLY ZEROING THEM OUT THROUGH MONDAY MORNING...IN LINE
WITH GUIDANCE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 302 PM EST SAT MAR 5 2016
THE FIRST FEW DAYS OF THE EXTENDED ARE EXPECTED TO BE WARM AND
DRY...AS A LARGE RIDGE OF HIGH PRESSURE STUBBORNLY REMAINS IN
PLACE ACROSS THE SOUTHEASTERN CONUS. A WEAK COLD FRONT IS FORECAST
TO MOVE OUT OF THE PLAINS TO START THE PERIOD...BUT WILL HAVE A
DIFFICULT TIME MAKING MUCH EASTWARD PROGRESS AT FIRST AS IT
ENCOUNTERS THE AFOREMENTIONED RIDGE. THE CURRENT DATA SUGGESTS
THAT THE FRONT WILL FINALLY BEGIN TO MOVE EASTWARD LATE IN THE
DAY WEDNESDAY...AS ITS PARENT UPPER LEVEL TROUGH MOVES EASTWARD
ALONG THE NORTHERN THIRD OF THE CONUS. WHAT WILL MOST LIKELY
HAPPEN IS THE NORTHERN SECTION OF THE FRONT WILL MOVE EAST WITH
THE UPPER TROUGH...AS THE SOUTHERN HALF OF THE BOUNDARY GETS HUNG
UP ALONG THE WESTERN EDGE OF THE RIDGE. AS THE RIDGE FINALLY
BEGINS TO BREAK DOWN WEDNESDAY NIGHT...THE WEAKENING COLD FRONT
SHOULD BE ABLE TO DRIFT SOUTHWARD ACROSS THE OHIO VALLEY AND
BECOME NEARLY STATIONARY ACROSS THE REGION FROM THURSDAY ONWARD.
THERE WILL BE A CHANCE OF THUNDERSTORMS WEDNESDAY NIGHT THROUGH
THURSDAY NIGHT AS THE FRONT MOVES ACROSS THE AREA. ONCE THE
BOUNDARY STALLS...AND INSTABILITY BECOMES TAPPED OUT...GENERAL
RAIN SHOWERS SHOULD DOMINATE FROM LATE FRIDAY NIGHT ONWARD.
TEMPERATURES THROUGH OUT THE UPCOMING WORK WEEKS WILL BE WELL
ABOVE NORMAL AS THE RIDGE REMAINS ENTRENCHED SOUTHERLY TO
SOUTHWESTERLY FLOW PERSISTS ACROSS THE REGION. HIGHS ARE EXPECTED
TO TOP OUT IN THE MID TO UPPER 60S ON MONDAY...IN THE LOW TO MID
70S TUESDAY THROUGH THURSDAY...AND AROUND 70 ON FRIDAY. IT WILL
FEEL LIKE SPRING ALL WEEK. OVERNIGHT LOWS WILL ALSO BE WELL ABOVE
NORMAL...WITH NIGHTLY MINIMUMS IN THE LOW TO MID 50S EVERY NIGHT
EXCEPT MONDAY NIGHT...WHEN THE MERCURY IS EXPECTED TO DROP INTO
THE LOW TO MID 40S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1250 PM EST SAT MAR 5 2016
A LOW PRESSURE SYSTEM IS DROPPING SOUTH ACROSS EAST KENTUCKY THIS
AFTERNOON. THIS IS RESULTING IN SCATTERED TO NUMEROUS LIGHT RAIN
SHOWERS MOVING IN FOR THE BULK OF THE AREA...LASTING INTO THE
LATE AFTERNOON. KEPT WITH PREVAILING VCSH MENTION THROUGHOUT THE
FIRST PART OF THE TAF ALONG WITH A FEW HOUR TEMPO GROUP TRYING TO
HIT THE BEST TIMING FOR THESE SHOWERS AND LOWER CIGS/VIS. THE LOW
AND ITS ASSOCIATED RAIN WILL QUICKLY EXIT EASTWARD OVERNIGHT. AS
HIGH PRESSURE FILLS IN...ANOTHER NIGHT OF SUBSIDENCE W/ LLVL
MOISTURE WILL SET UP...LIKELY LEADING TO MORE LOWER CIGS AND FOG
DEVELOPMENT ACROSS THE REGION. OVERALL...WINDS SHOULD REMAIN LIGHT
THROUGHOUT THE TAF PERIOD...PREDOMINATELY FROM THE SOUTHWEST BEFORE
BECOMING MORE WESTERLY BEHIND THE COLD FRONT...AFTER 00Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...AR
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS JACKSON KY
220 PM EST SAT MAR 5 2016
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 220 PM EST SAT MAR 5 2016
18Z SFC ANALYSIS SHOWS LOW PRESSURE MOVING SOUTH THROUGH EASTERN
KENTUCKY ON ITS TREK TO THE SOUTHEAST COAST. THIS IS PUSHING A
FAIRLY LARGE BAND OF SCATTERED TO NUMEROUS SHOWERS THROUGH THE CWA
WITH GENERALLY A TENTH TO TWO TENTHS OF AN INCH OF RAIN EXPECTED.
EARLIER...THIS LOW HELPED TO BREAK UP THE LOW CLOUDS AND FOG
RELEASING THE AREA FROM CHILLY TEMPERATURES IN THE LOWER AND
MIDDLE 30S. CURRENTLY...READINGS HAVE MADE IT INTO THE LOW 40S
NORTH AND THE LOWER 50S SOUTH ON SOUTH TO SOUTHWEST WINDS.
DEWPOINTS...MEANWHILE...HAVE ALSO CLIMBED WITH THE UPPER 30S AND
40S MOST COMMON AS THE RAIN STARTS TO MOVE IN.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST AS A COMPACT WAVE STRENGTHENS AND MOVES
THROUGH THE SOUTHERN APPALACHIANS...TO THE SOUTHEAST COAST LATER
TODAY AND INTO TONIGHT. THIS SHARP LITTLE FEATURE WILL BE FOLLOWED
BY AN EQUALLY DISTINCT RIDGE BUILDING INTO KENTUCKY FROM THE
SOUTHERN PLAINS. THIS RIDGE PLANTS ITSELF FIRMLY OVER THE AREA ON
SUNDAY...BUILDING INTO MONDAY AS IT STARTS TO BE PUMPED UP DUE TO
ITS POSITION DOWNSTREAM OF A LARGE DIGGING WEST COAST TROUGH. LOOK
FOR THE RIDGE TO KEEP ANY MID LEVEL WAVES OF ENERGY TO THE NORTH
OF THE AREA KEEPING THE WX QUIET. GIVEN THE MODEL AGREEMENT AND
MAINLY JUST NEAR TERM WEATHER CONCERNS...HAVE FAVORED A GENERAL
MODEL BLEND WITH STRONG LEAN TOWARD THE HRRR AND NAM12
SOLUTIONS.
SENSIBLE WEATHER WILL FEATURE A RELATIVELY WEAK LOW PRESSURE SFC
WAVE PASSING THROUGH EAST KENTUCKY WITH BULK OF THE SHOWERS
MOVING THROUGH THIS AFTERNOON AND GRADUALLY DIMINISHING INTO THE
EVENING FROM NORTHWEST TO SOUTHEAST. COOLER AIR DOES FOLLOW THIS
LOW BUT NOT ENOUGH TO WORRY ABOUT ANY SNOW MIXING IN BEFORE THE
LAST OF THE PCPN DEPARTS. OF A LARGER CONCERN WILL BE THE
POTENTIAL FOR FOG DEVELOPING AGAIN TONIGHT. GIVEN THE AMPLE LOW
LEVEL MOISTURE LEFT BEHIND AROUND AND ANTICIPATED SUBSIDENCE
INVERSION HAVE HIT THE FOG RATHER HARD IN THE GRIDS WITH SOME
AREAS HAVING SOME DENSE FOG. RIDGES MAY SEE LOW VISIBILITIES...AS
WELL...WITH THE LOW CLOUDS SETTLING IN AFTER MIDNIGHT. THIS WILL
ALL CLEAR OUT FAIRLY QUICKLY ON SUNDAY...THOUGH...WITH SUNSHINE
RETURNING AND SOUTHERLY WINDS HELPING TO BRING TEMPS BACK INTO THE
LOWER AND MIDDLE 50S BY AFTERNOON...FOR MOST PLACES. HIGH PRESSURE
MOVING OFF TO THE EAST WILL LIKELY SET THE STAGE FOR A DECENT
RIDGE TO VALLEY TEMPERATURE SPLIT SUNDAY NIGHT INTO MONDAY
MORNING UNDER MOSTLY CLEAR SKIES AND LIGHT WINDS. ALSO...WOULD
ANTICIPATE SOME VALLEY FOG DEVELOPING LATE SUNDAY NIGHT THROUGH
DAWN MONDAY.
USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WIND GRIDS
THROUGH THE NIGHT BEFORE FAVORING THE SUPERBLEND THEREAFTER. MADE
THE MOST SIGNIFICANT CHANGES TO THE T GRIDS ON SUNDAY NIGHT TO
ACCOUNT FOR THE ANTICIPATED RIDGE AND VALLEY DISTINCTIONS. AS FOR
POP...ENDED UP CLOSEST TO THE HIGHER MET VALUES INTO THE EVENING
BEFORE NEARLY ZEROING THEM OUT THROUGH MONDAY MORNING...IN LINE
WITH GUIDANCE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 359 AM EST SAT MAR 5 2016
WARMING TEMPERATURES AND A DRY START TO THE WEEK REMAIN IN THE
OFFING COURTESY OF BUILDING HEIGHTS/THICKNESSES ASSOCIATED WITH
BROAD EASTERN CONUS RIDGING. FURTHER WARMING WILL ENSUE AS FLOW
BACKS SOUTHWEST ALOFT IN RESPONSE TO AN UPPER LEVEL LOW DIGGING
THROUGH BAJA CALIFORNIA INTO CHIHUAHUA MEXICO. WELL ABOVE NORMAL
TEMPERATURES WILL BE THE RULE WITH HIGHS LOOKING TO TOP OUT BETWEEN
THE MID 60S TO MID 70S AS LOWS FROM TUESDAY MORNING INTO THE WEEKEND
ONLY FALL INTO THE MID 40S TO MID 50S.
GIVEN THE DEEP SOUTHERN TRACK OF THE AFOREMENTIONED SYSTEM...SURFACE
LOW PRESSURE DEVELOPING ACROSS THE SOUTHERN PLAINS WILL BE SLOW TO
EJECT EASTWARD IN AN AMPLIFIED PATTERN AS SURFACE RIDGING
ESTABLISHES A LENGTHY RESIDENCE TIME ACROSS THE MID TO SOUTHERN
ATLANTIC COAST. THIS WILL LIKELY KEEP ANY EARLIER WEEK
RAINFALL...RESULTING FROM AN INITIAL SHORTWAVE IMPULSE...WELL WEST
OF INTERSTATE 71. PROSPECTS FOR RAINFALL ACROSS CENTRAL INTO EASTERN
KENTUCKY LOOK TO BECOME MUCH BETTER FOR MID-LATE WEEK AS UPPER
ENERGY APPROACHES IN TANDEM WITH A SURFACE LOW AND PLENTY OF DEEP
LAYER MOISTURE. APPRECIABLE THUNDER CHANCES CONTINUE TO LOOK
POSSIBLE AS LONG AS INSTABILITY CAN MATERIALIZE AMID PLENTY OF MID-
HIGH CLOUD COVER. A NORTHERN STREAM TROUGH MAY ALSO ATTEMPT TO DIVE
FAR ENOUGH SOUTH TO AID IN PROVIDING ADDITIONAL LIFT FOR
SHOWER/THUNDERSTORM POTENTIAL. DEPENDING ON THE TRACK/EVOLUTION OF
THE UPPER LOW...RAINFALL COULD VERY WELL LAST INTO THE WEEKEND. WILL
HAVE TO MONITOR HEAVY RAIN/FLOODING THREAT GOING FORWARD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1250 PM EST SAT MAR 5 2016
A LOW PRESSURE SYSTEM IS DROPPING SOUTH ACROSS EAST KENTUCKY THIS
AFTERNOON. THIS IS RESULTING IN SCATTERED TO NUMEROUS LIGHT RAIN
SHOWERS MOVING IN FOR THE BULK OF THE AREA...LASTING INTO THE
LATE AFTERNOON. KEPT WITH PREVAILING VCSH MENTION THROUGHOUT THE
FIRST PART OF THE TAF ALONG WITH A FEW HOUR TEMPO GROUP TRYING TO
HIT THE BEST TIMING FOR THESE SHOWERS AND LOWER CIGS/VIS. THE LOW
AND ITS ASSOCIATED RAIN WILL QUICKLY EXIT EASTWARD OVERNIGHT. AS
HIGH PRESSURE FILLS IN...ANOTHER NIGHT OF SUBSIDENCE W/ LLVL
MOISTURE WILL SET UP...LIKELY LEADING TO MORE LOWER CIGS AND FOG
DEVELOPMENT ACROSS THE REGION. OVERALL...WINDS SHOULD REMAIN LIGHT
THROUGHOUT THE TAF PERIOD...PREDOMINATELY FROM THE SOUTHWEST BEFORE
BECOMING MORE WESTERLY BEHIND THE COLD FRONT...AFTER 00Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...GUSEMAN
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
110 PM EST SAT MAR 5 2016
.UPDATE...
ISSUED AT 110 PM EST SAT MAR 5 2016
THE TEMPERATURES HAVE NOW PROPERLY REBOUNDED SO HAVE MAINLY
ADJUSTED THE FORECAST WITH THIS UPDATE TO ACCOUNT FOR THE INBOUND
SHOWERS FROM THE NORTHWEST. ALSO...DID FINE TUNE THE T AND TD
GRIDS PER THE LATEST OBS AND TRENDS. THESE GRIDS HAVE BEEN SENT TO
THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 955 AM EST SAT MAR 5 2016
14Z SFC ANALYSIS SHOWS LOW PRESSURE DIVING SOUTHEAST THROUGH THE
GREAT LAKES WITH A WEAK COLD FRONT PASSING THE MID MISSISSIPPI
VALLEY. HERE TO THE EAST...A MID LEVEL DISTURBANCE IS DEPARTING
THE CENTRAL APPALACHIANS. THIS IS RESULTING IN SOME LIGHT PCPN
DROPPING THROUGH EAST KENTUCKY THIS MORNING. IN ADDITION TO THE
SPRINKLES AND LIGHT RAIN...AREAS OF FOG...LOCALLY DENSE...PLAGUED
THE HIGHER ELEVATIONS THROUGH EAST KENTUCKY EARLY THIS MORNING.
THE FOG IS STARTING TO DISSIPATE WITH IMPROVING VISIBILITY AND
LIFTING CEILINGS. HOWEVER...THE LOW CLOUDS AND PCPN ARE RETARDING
A TEMPERATURE RISE SO FAR THIS MORNING WITH MOST PLACES STILL IN
THE LOW 30S. THE APPROACH OF THE WEAKENING LOW AND ITS FRONT
SHOULD MIX OUT THE LOWER CLOUDS BY MIDDAY WITH WARMING
TEMPERATURES THE RESULT...THOUGH ANOTHER ROUND MORE SUBSTANTIVE
SHOWERS WILL LIKELY DEVELOP AND CROSS EAST KENTUCKY THIS
AFTERNOON. HAVE ADJUSTED THE FORECAST TO SLOW THE TEMP RISE THIS
MORNING AND TO FINE TUNE THE POPS/WX THROUGH THE AFTERNOON PER THE
LATEST HRRR AND NAM12. DID ALSO TWEAK THE DEWPOINTS...CURRENTLY
REPORTING SIMILAR VALUES TO DRY TEMPS AT MOST SITES...PER THE
LATEST OBS AND TRENDS. LIGHT WINDS EARLY THIS MORNING WILL SHIFT
TO THE SOUTHWEST AND PICK UP TO NEAR 10 MPH THIS AFTERNOON ALSO
HELPING TEMPS TO REBOUND INTO THE 40S. THE GRID UPDATES HAVE BEEN
SENT TO THE NDFD AND WEB SERVERS...WITH A FRESHENED SET OF ZONES
AND HWO ALSO ISSUED.
UPDATE ISSUED AT 656 AM EST SAT MAR 5 2016
CURRENT RADAR IS SHOWING A LINE OF PRECIPITATION MOVING ACROSS THE
NORTHERN PORTION OF THE CWA. ACCORDING TO THE LATEST
OBSERVATIONS...PRECIP IS LIKELY STILL NOT HITTING THE
GROUND...WITH ONLY ONE BRIEF OBSERVATION OF LIGHT SNOW IN THE
CINCINNATI AREA UNDER A HIGHER RETURN OVER THE LAST HOUR. IT IS
POSSIBLE THAT SOME FLURRIES ARE OCCURRING OUT OF THIS GIVEN
TEMPERATURES AT OR NEAR THE FREEZING MARK...BUT NOTHING IS
EXPECTED TO ACCUMULATE. OVER THE NEXT HOUR...EXPECT RETURNS TO
INTENSIFY AND PRECIP TO BEGIN HITTING THE GROUND...BUT NOT BEFORE
TEMPERATURES BEGIN A WARMING TREND ABOVE FREEZING AND PRECIP
CHANGES TO MAINLY RAIN.
MEANWHILE...STILL SEEING QUITE A BIT OF FOG ACROSS THE REMAINDER
OF THE CWA...THOUGH THERE HAS BEEN SIGNS OF VIS IMPROVEMENT AT
MANY SITES. ACCORDING TO THE OBS IT SEEMS AS THOUGH MUCH OF THE
FOG IS ELEVATED AT THIS POINT...MAINLY AFFECTING THE RIDGE TOPS. SEVERAL
OBSERVATIONS ACROSS EASTERN KY ARE ALSO STILL REPORTING TEMPS AT
OR JUST BELOW 32 DEGREES...SO WILL CONTINUE MENTION OF FREEZING
FOG AS WELL IN THE GRIDS FOR THE NEXT HOUR. CURRENT SPS
HIGHLIGHTING PATCHY DENSE FOG AND POSSIBLE SLICK CONDITIONS FROM
FREEZING FOG/SLICK ROADWAYS WILL BE ALLOWED TO EXPIRE AT 7AM...AS
FOG SHOULD CONTINUE LIFTING/MIXING OUT AND TEMPERATURES WILL BE
WARMING AFTER THIS POINT.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 349 AM EST SAT MAR 5 2016
LINGERING LLVL MOISTURE AND STRONG SUBSIDENCE IN PLACE THROUGH THE
FIRST PART OF THE NIGHT HAS LED TO FOG DEVELOPMENT ACROSS MUCH OF
THE CWA. GIVEN TEMPERATURES AT OR BELOW FREEZING IN MANY LOCATIONS
AS WELL...THIS ALSO CREATED A SET UP FOR POTENTIAL FREEZING FOG. AN
AREA OF LOW PRESSURE IS CURRENTLY MOVING EASTWARD INTO THE UPPER
GREAT LAKES REGION AS OF 8Z THIS MORNING. THIS IS PUSHING THE
SURFACE HIGH IN PLACE EAST OF THE REGION...AND ALLOWING MID AND
UPPER LEVEL MOISTURE TO BEGIN FILTERING INTO THE REGION. DESPITE
THIS...SOUNDINGS STILL SUPPORT A DECENT LLVL INVERSION WHICH WILL
LIKELY KEEP THE FOG AND FREEZING FOG IN PLACE THROUGHOUT THE REST OF
THE NIGHT.
BY 12Z THIS MORNING...THE LOW IS EXPECTED TO BEGIN QUICKLY DROPPING
SOUTHEASTWARD...CLIPPING THE FAR NE PORTION OF THE STATE BY LATE
THIS AFTERNOON...BEFORE EXITING EASTWARD OVERNIGHT. THIS QUICK DROP
SOUTHWARD WILL LIKELY CLEAR OUT ANY REMAINING FOG ACROSS THE REGION.
OVERALL THIS SYSTEM IS BOTH FAST MOVING AND RELATIVELY WEAK.
HOWEVER...THERE WILL BE ENOUGH MOISTURE SUPPORT FROM LLVL SRLY WINDS
TO PROMOTE SOME SCATTERED BUT LIGHT PRECIP POTENTIAL ACROSS THE CWA.
LATEST HI RES MODELS ARE SHOWING PRECIP DEVELOPING ALONG OUR FAR NW
CWA AROUND OR JUST AFTER 12Z THIS MORNING...WITH SCATTERED ACTIVITY
OVERSPREADING FROM NW TO SE THROUGHOUT THE DAY...THEN EXITING TO OUR
EAST OVERNIGHT. BEST QPF AND POPS WILL BE ACROSS THE NORTHERN AND
FAR EASTERN CWA...CLOSEST TO THE CENTER OF THE LOW.
WILL CONTINUE TO MONITOR THE TEMPERATURES AS THE PRECIP BEGINS TO
NEAR THE REGION THIS MORNING...AS IT IS LIKELY THAT BELOW FREEZING
TEMPS COULD LEAD TO SOME SNOW AT ONSET...BEFORE CHANGING OVER TO ALL
RAIN AS CONDITIONS WARM TO ABOVE FREEZING AFTER 12Z. OVERALL...NOT
LOOKING AT ANY ACCUMULATIONS IF SNOW DOES OCCUR...AND SHOULD BE A
PRETTY QUICK TURNOVER. OTHERWISE...TEMPERATURES WILL REMAIN ABOVE
FREEZING THROUGHOUT THE DURATION OF THE EVENT...SO REST OF PRECIP
SHOULD FALL AS ALL RAIN.
AMPLIFIED RIDGING WILL SHIFT EASTWARD ACROSS KY BEHIND THE EXITING
SHORTWAVE AND LOW PRESSURE SYSTEM TONIGHT AND THROUGH THE DAY
SUNDAY. WITH LINGERING MOISTURE IN PLACE ONCE MORE TONIGHT...AND
STRONG SUBSIDENCE TAKING HOLD...EXPECT SOME FOG DEVELOPMENT TO
RESULT ONCE MORE. IT IS POSSIBLE THAT THERE COULD BE SOME WIDESPREAD
AND/OR DENSE FOG IN LOCATIONS THAT RECEIVE RAINFALL TODAY...AND NEAR
SOME BODIES OF WATER. HOWEVER...GIVEN THE LOW CONFIDENCE ON WHERE
BEST IMPACTS FROM RAIN WILL BE...JUST STUCK WITH PATCHY FOG MENTION
ACROSS ENTIRE CWA AT THIS TIME. SURFACE HIGH PRESSURE WILL ACCOMPANY
THIS AMPLIFIED RIDGING...CROSSING DIRECTLY OVER KY DURING THE DAY
SUNDAY. AS A RESULT...EXPECT LIGHT WINDS...CLEARING SKIES...AND
TEMPERATURES WARMING INTO THE MID 50S.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 359 AM EST SAT MAR 5 2016
WARMING TEMPERATURES AND A DRY START TO THE WEEK REMAIN IN THE
OFFING COURTESY OF BUILDING HEIGHTS/THICKNESSES ASSOCIATED WITH
BROAD EASTERN CONUS RIDGING. FURTHER WARMING WILL ENSUE AS FLOW
BACKS SOUTHWEST ALOFT IN RESPONSE TO AN UPPER LEVEL LOW DIGGING
THROUGH BAJA CALIFORNIA INTO CHIHUAHUA MEXICO. WELL ABOVE NORMAL
TEMPERATURES WILL BE THE RULE WITH HIGHS LOOKING TO TOP OUT BETWEEN
THE MID 60S TO MID 70S AS LOWS FROM TUESDAY MORNING INTO THE WEEKEND
ONLY FALL INTO THE MID 40S TO MID 50S.
GIVEN THE DEEP SOUTHERN TRACK OF THE AFOREMENTIONED SYSTEM...SURFACE
LOW PRESSURE DEVELOPING ACROSS THE SOUTHERN PLAINS WILL BE SLOW TO
EJECT EASTWARD IN AN AMPLIFIED PATTERN AS SURFACE RIDGING
ESTABLISHES A LENGTHY RESIDENCE TIME ACROSS THE MID TO SOUTHERN
ATLANTIC COAST. THIS WILL LIKELY KEEP ANY EARLIER WEEK
RAINFALL...RESULTING FROM AN INITIAL SHORTWAVE IMPULSE...WELL WEST
OF INTERSTATE 71. PROSPECTS FOR RAINFALL ACROSS CENTRAL INTO EASTERN
KENTUCKY LOOK TO BECOME MUCH BETTER FOR MID-LATE WEEK AS UPPER
ENERGY APPROACHES IN TANDEM WITH A SURFACE LOW AND PLENTY OF DEEP
LAYER MOISTURE. APPRECIABLE THUNDER CHANCES CONTINUE TO LOOK
POSSIBLE AS LONG AS INSTABILITY CAN MATERIALIZE AMID PLENTY OF MID-
HIGH CLOUD COVER. A NORTHERN STREAM TROUGH MAY ALSO ATTEMPT TO DIVE
FAR ENOUGH SOUTH TO AID IN PROVIDING ADDITIONAL LIFT FOR
SHOWER/THUNDERSTORM POTENTIAL. DEPENDING ON THE TRACK/EVOLUTION OF
THE UPPER LOW...RAINFALL COULD VERY WELL LAST INTO THE WEEKEND. WILL
HAVE TO MONITOR HEAVY RAIN/FLOODING THREAT GOING FORWARD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1250 PM EST SAT MAR 5 2016
A LOW PRESSURE SYSTEM IS DROPPING SOUTH ACROSS EAST KENTUCKY THIS
AFTERNOON. THIS IS RESULTING IN SCATTERED TO NUMEROUS LIGHT RAIN
SHOWERS MOVING IN FOR THE BULK OF THE AREA...LASTING INTO THE
LATE AFTERNOON. KEPT WITH PREVAILING VCSH MENTION THROUGHOUT THE
FIRST PART OF THE TAF ALONG WITH A FEW HOUR TEMPO GROUP TRYING TO
HIT THE BEST TIMING FOR THESE SHOWERS AND LOWER CIGS/VIS. THE LOW
AND ITS ASSOCIATED RAIN WILL QUICKLY EXIT EASTWARD OVERNIGHT. AS
HIGH PRESSURE FILLS IN...ANOTHER NIGHT OF SUBSIDENCE W/ LLVL
MOISTURE WILL SET UP...LIKELY LEADING TO MORE LOWER CIGS AND FOG
DEVELOPMENT ACROSS THE REGION. OVERALL...WINDS SHOULD REMAIN LIGHT
THROUGHOUT THE TAF PERIOD...PREDOMINATELY FROM THE SOUTHWEST BEFORE
BECOMING MORE WESTERLY BEHIND THE COLD FRONT...AFTER 00Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...JMW
LONG TERM...GUSEMAN
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
259 PM EST SAT MAR 5 2016
.SYNOPSIS...
WEAK LOW PRESSURE WILL MOVE QUICKLY ACROSS THE AREA TONIGHT INTO
EARLY SUNDAY MORNING. HIGH PRESSURE RETURNS LATER SUNDAY AND
WILL PERSIST OVER THE SOUTHEASTERN STATES THROUGH THE MIDDLE OF
THE WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
SFC HIGH PRESSURE IS CENTERED NEAR THE VA TIDEWATER THIS AFTERNOON
AS THE WEAK CLIPPER LOW DIVES INTO THE OHIO VALLEY. THE FLURRIES
WITH THE LEAD DISTURBANCE ALOFT HAVE DISSIPATED...AND BEHIND IT
THERE HAVE BEEN SOME BREAKS IN THE CLOUDS. BULK OF THE AFTERNOON
WILL REMAIN DRY ACROSS MOST OF THE AREA.
TWO AREAS OF PRECIP TO OUR WEST TO WATCH...EACH ASSOCIATED WITH A
VORT MAX ALOFT. ONE AREA IS CURRENTLY MOVING INTO EASTERN KY WHILE
THE OTHER DROPS SE FROM MI. HAVE LARGELY BASED THE POPS FOR THIS
EVENING AND OVERNIGHT ON THE RAP AND HRRR...WITH SOME SUPPORT FROM
OTHER HI-RES MODELS AND THE NAM/GFS. ECMWF IS A NOTABLE DRY OUTLIER
AND IS NOT TOTALLY OUT OF THE REALM OF POSSIBILITY...THUS WHY POPS
HAVE BEEN KEPT AT 60 PCT OR LOWER EXCEPT ALONG THE ALLEGHENY FRONT.
THE FORECAST HINGES ON THE TWO AREAS OF PRECIP MERGING AND
PROCEEDING ACROSS THE MOUNTAINS. EVEN IF IT DOES...QPF WILL BE
RATHER LIGHT AS THE SFC LOW FIZZLES AND THE PRIMARY VORT MAX IN THE
TROUGH HEADS TO THE SE STATES. THE TREND WITH THE MORNING GUIDANCE
WAS TO REDUCE QPF ALONG THE PA BORDER. KIND OF DOUBT COVERAGE IS
COMPLETELY UNIFORM EITHER. HAVE CONTINUED TO INDICATE A TRANSITION
TO RA/SN MIX THEN SN GENERALLY WEST OF I-95. LOW TEMPS WILL FALL TO
NEAR THE FREEZING MARK AND FORECAST SOUNDINGS ARE NOT AS COLD ALOFT
AS THE EVENT A COUPLE DAYS AGO. SO ALL PUT TOGETHER...SOME PLACES
COULD RECEIVE A SLUSHY COATING (BUT NOT NECESSARILY ALL)...WITH A
WORST CASE BEING UP TO AN INCH. 1-2 INCHES REMAIN POSSIBLE ALONG THE
ALLEGHENY FRONT.
FAIRLY GOOD TIMING AGREEMENT THAT THE TROUGH AXIS WILL BE PASSING
QUICKLY TO THE EAST AT 12Z SUNDAY...ALLOWING ANY LINGERING SHOWERS
TO EXIT BY 9 AM OR SO. HOWEVER CLOUDS MAY NOT BE AS QUICK TO
DEPART...ALTHOUGH SUN SHOULD BREAK THROUGH BY AFTERNOON. HIGHS WILL
BE ABLE TO REBOUND INTO THE MID 40S TO LOWER 50S.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
RIDGING AT THE SFC AND ALOFT WILL BUILD IN EARNESTLY SUNDAY NIGHT.
AMOUNT OF MID AND HIGH CLOUDS WILL DETERMINE THE EFFECTIVENESS OF
RADIATIONAL COOLING. WILL FORECAST LOWS ON EITHER SIDE OF
FREEZING.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
WINDS WILL HAVE SHIFTED TO SOUTHERLY MONDAY MORNING ACROSS THE
ENTIRE AREA...AS SFC HIGH SHIFTS TO OUR SOUTHEAST AND WAA COMMENCES.
LONG PERIOD OF UNINTERRUPTED RETURN FLOW WILL ALLOW AIRMASS TO
WARM/MOISTEN SUBSTANTIALLY FROM MONDAY THROUGH AT LEAST
WEDNESDAY...AS SFC HIGH REMAINS ANCHORED TO OUR SOUTHEAST AND LARGE
EAST COAST RIDGE DEVELOPS. RECORDS APPEAR SAFE AT THIS
POINT...THOUGH WITH HIGHS IN THE M/L 70S BY WEDNESDAY...NEARLY 20
DEGREES ABOVE NORMAL...IT WILL FEEL MORE LIKE EARLY MAY.
CHANGES MAY ARRIVE TO PARTS OF THE AREA THURSDAY...AS WEAK FRONT
POSSIBLY NUDGES ITS WAY INTO THE NORTHERN HALF OF THE AREA. GFS MORE
AGGRESSIVE THAN ECMWF WITH QPF OVER THE AREA THURSDAY...WHILE ECMWF
KEEPS MEANINGFUL QPF CONFINED TO OUR FAR NORTHWEST UNTIL EARLY
FRIDAY MORNING WITH THE FRONT THEN WASHING OUT OVER THE AREA.
EAST COAST RIDGE BEGINS TO BREAK DOWN AND SHIFT EAST FRIDAY INTO
SATURDAY...AS UPPER LOW...THAT HAD BEEN DISLODGED FROM THE MAIN
FLOW...BEGINS TO EJECT OUT OF THE SOUTHERN PLAINS. THIS SETS UP AN
UNSETTLED PERIOD...THOUGH SPATIOTEMPORAL SPREAD OF THE KEY FEATURES
DURING THIS TIME IS RATHER LARGE...WHICH PREVENTS NOTHING MORE THAN
CHC POPS THROUGH THE PERIOD.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
LOOKING DOUBTFUL THERE WILL BE ANY IMPACTS AT THE TERMINALS THROUGH
EARLY EVENING...JUST CONTINUED CIGS NEAR FL050 AT TIMES. WEAK
DISTURBANCE PUSHES THROUGH TONIGHT. THINK AT A MINIMUM THERE WILL BE
A PERIOD OF MVFR CIGS. PRECIP IS A LITTLE MORE IN DOUBT. HAVE
ADVERTISED A PERIOD OF RAIN AND/OR SNOW SHOWERS OVERNIGHT...ALTHOUGH
WIDESPREAD COVERAGE IS NOT GUARANTEED. HAVE THUS LIMITED VSBY
RESTRICTIONS TO MVFR FOR NOW AND WILL NOTE HERE THAT IFR IS
POSSIBLE...ESPECIALLY IN ANY SNOW. ANY THREAT OF PRECIP WILL LIKELY
END BY 12Z. HOWEVER CIGS MAY BE SLOW TO SCATTER OUT AND HAVE LEFT
MENTION OF CLOUDS AROUND FL050 THROUGHOUT SUNDAY. SE WINDS 5-10 KT
THIS AFTERNOON...BECOMING VRB TONIGHT...THEN NORTHERLY 5-10 KT
SUNDAY. VFR CONDITIONS ARE EXPECTED SUNDAY NIGHT AS HIGH PRESSURE
BUILDS.
VFR MONDAY THROUGH MIDWEEK UNDER HIGH PRESSURE.
&&
.MARINE...
LIGHT S/SE FLOW ON THE WATERS THIS AFTERNOON AS HIGH PRESSURE
DEPARTS. WEAK LOW PRESSURE CROSSES THE AREA TONIGHT WITH LITTLE IN
THE WAY OF WINDS BUT PERHAPS A LIGHT RAIN OR SNOW SHOWER. NORTHERLY
WINDS DEVELOP SUNDAY...ALTHOUGH STILL LOOKING LIKE THEY WILL REMAIN
BELOW SCA. LIGHT SOUTHERLY FLOW DEVELOPS SUNDAY NIGHT.
WINDS FOLLOW A DIURNAL CYCLE BEYOND MONDAY...WITH ELEVATED/LIGHT
SOUTHERLY WINDS DURING THE DAY/NIGHT. ATTM...IT APPEARS WINDS REMAIN
AOB SCA...THOUGH THERE COULD BE PERIODS OF WIND GUSTS NEAR SCA
DURING THE AFTERNOONS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ADS
NEAR TERM...ADS
SHORT TERM...ADS
LONG TERM...MSE
AVIATION...ADS/MSE
MARINE...ADS/MSE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
315 PM EST SAT MAR 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EST SAT MAR 5 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWS A RIDGE OVER THE ROCKIES
AND A TROF OVER ERN NAMERICA. SHORTWAVE THAT BROUGHT SNOW INTO UPPER
MI OVER THE LAST 12HRS OR SO IS TRACKING SE THRU WI. THIS WILL BE
THE FINAL SHORTWAVE TO DROP SE THRU THE AREA BEFORE A TRANSITION TO
A WARM SPLIT FLOW PATTERN WITH ABOVE NORMAL HEIGHTS AND W TO SW FLOW
ACROSS THE UPPER GREAT LAKES NEXT WEEK. RADAR TRENDS OVER THE LAST
COUPLE OF HRS SHOW SNOW DIMINISHING OVER UPPER MI...AND UPSTREAM...
KDLH RADAR SHOWS VERY LITTLE PCPN REMAINING. THERE WERE OBS AND
REPORTS OF SOME -FZDZ EARLIER IN THE NIGHT OVER WRN UPPER MI AND NRN
WI AS THE HEAVIER SNOW DEPARTED. RECENTLY...THERE ARE FEWER OBS
SHOWING UNKNOWN PCPN...SO -FZDZ MAY BE DIMINISHING.
WITH SHORTWAVE CONTINUING SE TODAY...DIMINISHING PCPN WILL END FROM
NW TO SE. SOUTHERLY FLOW ON LAKE MI PERSISTS THRU MID TO LATE
MORNING WHICH SHOULD HELP WEAKLY LAKE ENHANCED SNOW TO LINGER.
THUS...HIGHEST POPS WILL PAINTED OVER THE E THIS MORNING WITH
PERHAPS ANOTHER HALF INCH OR SO OF SNOW ACCUMULATION. TO THE W...
WILL KEEP A MENTION OF -FZDZ/-SN MAINLY IN THE COUNTIES BORDERING WI
FOR THE NEXT FEW HRS. SATELLITE IMAGERY SHOWS CLEARING NOT THAT FAR
AWAY ACROSS NRN LAKE SUPERIOR. WITH HIGH PRES RIDGE BUILDING INTO
THE UPPER GREAT LAKES THIS AFTN...LOW-LEVEL NORTHERLY WINDS AHEAD OF
THE RIDGE WILL DIMINISH. THIS INCREASES THE UNCERTAINTY IN HOW MUCH
CLEARING WILL OCCUR...ESPECIALLY SINCE UPSLOPE FLOW OFF THE LAKE
UNDER A LOWERING INVERSION SHOULD GREATLY SLOW THE CLEARING PROCESS.
KEWEENAW OBVIOUSLY HAS THE BEST CHC OF AT LEAST PARTIALLY CLEARING
OUT TODAY GIVEN THE CLOSE PROXIMITY OF CLEAR SKIES ALREADY EARLY
THIS MORNING. FOR NOW...FCST WILL SHOW A VERY GRADUAL DECREASE IN
CLOUDS FROM THE N AND NW THIS AFTN INTO THIS EVENING.
CLOUD FCST INTO TONIGHT REMAINS A BIT TRICKY. IF THE EXTENSIVE LOW
CLOUDS ACROSS MN/WI PERSIST THRU THE DAY...THESE CLOUDS MAY MOVE
BACK INTO THE AREA TONIGHT ONCE S TO SW FLOW DEVELOPS/INCREASES
AFTER THE HIGH PRES RIDGE PASSES. OTHERWISE...PROVIDED MUCH OF
TODAYS CLOUD COVER DEPARTS BY EVENING...THERE WILL BE AN OPPORTUNITY
FOR TEMPS TO FALL QUICKLY THIS EVENING UNDER LIGHT/CALM WIND. LEANED
FCST TO THE COLDER BIAS CORRECTED REGIONAL/GLOBAL CANADIAN MODELS
DUE TO THEIR NORMAL SUPERIOR PERFORMANCE IN RADIATIONAL COOLING
SITUATIONS. TRADITIONAL COLD SPOTS WILL FALL DOWN INTO THE MID TEENS
IF SKIES ARE MOSTLY CLEAR THIS EVENING.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 314 PM EST SAT MAR 5 2016
THE MEDIUM/LONG RANGE FCST PERIOD WL FEATURE WELL ABOVE NORMAL TEMPS
WITH PACIFIC AIR/ABOVE NORMAL HGTS DOMINATING THE CONUS. WHILE THERE
COULD BE SOME RA SHOWERS ON MON/TUE ASSOCIATED WITH A SHRTWV RIDING
NEWD OUT OF THE PLAINS TOWARD THE WRN GREAT LKS...RA TOTALS SHOULD
BE LIMITED OVERALL. OTRW...MOST OF THE MEDIUM/EXTENDED RANGE PERIOD
WL BE DRY.
SUN NGT/MON...GUSTY SW WINDS SUN EVNG WL DIMINISH THRU THE NGT AS
THE PRES GRADIENT RELAXES WITH PASSAGE OF ONTARIO SHRTWV/PRES FALL
CENTER TO THE E...SO THE GUSTY WINDS WL SUBSIDE. SOME OF THE MODELS
GENERATE SOME LGT PCPN OVER MAINLY THE SE CWA IN THE EVNG RELATED TO
AREA OF SHARPER ISENTROPIC ASCENT BEST SHOWN ON THE 300K SFC /ABOUT
H7/ AND SOME MODEST ELEVATED INSTABILITY ABOVE THE ACCOMPANYING H85-
7 WARMING. BUT ANY OF THIS PCPN SHOULD DIMINISH OVERNGT WITH EXIT OF
THE SHARPER ISENTROPIC ASCENT AND ONSET OF MID LVL DRYING AS UPR RDG
BUILDS INTO THE AREA WITH FCST SDNGS SHOWING MORE MID LVL DRYING/
CAPPING. DESPITE THESE NEGATIVE DYNAMICS...MANY OF THE MODEL
CONTINUE TO GENERATE SOME SPOTTY LGT PCPN THRU THE NGT AND ON MON
OVER MUCH OF THE CWA. SUSPECT THIS PCPN IS RELATED TO FCST GRADUAL
INFLUX OF LLVL MSTR...SO WL MAINTAIN FCST OF DRIZZLE/FOG DVLPG OVER
MELTING SN COVER IN THE PRSENCE OF SOME NOCTURNAL COOLING INTO MON
MRNG. EXPECT WELL ABOVE NORMAL TEMPS WITH MIN TEMPS HOLDING ABOVE 32
ON SUN NGT. ALTHOUGH THE LINGERING LO CLDS ON MON WL LIMIT THE
DIURNAL TEMP RECOVERY...TEMPS WL STILL TOP OUT IN THE 40S TO PERHAPS
AS HI AS 50 OVER THE FAR W AS H85 TEMPS REBOUND.
MON NGT/TUE...A SHRTWV MOVING THRU THE WRN PLAINS ON MON IS FCST TO
LIFT NEWD AND INTO MN ON TUE...TENDING TO SHEAR OUT IN THE PROCESS.
THIS TREND...ALONG WITH LINGERING MID LVL DRY AIR UNDER THE HIER
HGTS/DRY SLOTTING TO THE E OF THE SHRTWV TRACK...WL LIMIT OVERALL
POPS AND QPF. BEST CHANCE FOR THE SOMEWHAT HIER POPS WL BE LATE MON
NGT/TUE MRNG SINCE THE SFC LO IS FCST TO PASS TO THE W THRU MN ON
TUE AND THE AIRMASS WL BE UNSEASONABLY WARM WITH H85 TEMPS FCST AS
HI AS 8 TO 9C...ANY PCPN WL BE IN THE FORM OF RA AS SFC TEMPS RISE
AOA 50 ON TUE AWAY FM THE COOLING INFLUENCE OF LK MI. THE PERSISTENT
SLY FLOW AND INFLUX OF WARMER/MOISTER LLVL AIR INTO THE CWA WL BRING
MORE FOG AND SOME DRIZZLE...ESPECIALLY AWAY FM THE DOWNSLOPE AREAS
ACRS THE NW CWA. STILL THINK THERE IS THE POTENTIAL FOR AN ELEVATED
TS LATE MON NGT/TUE WITH ARRIVAL OF H7-5 LAPSE RATES AS HI AS 7.5-
8.5C/KM DESPITE CONCERNS THAT MID LVL DRY AIR/CAPPING MIGHT BE TOO
PRONOUNCED TO ALLOW DEEP CONVECTION IN THE ABSENCE OF SGNFT DEEP LYR
QVECTOR CNVGC WITH MORE SHEARED OUT SHRTWV. THE 12Z GFS CONTINUES
THE TREND FM THAT MODEL SHOWING A FASTER COLD FROPA ON TUE WITH THIS
BNDRY REACHING NEWBERRY NEAR 00Z WED. ALTHOUGH THE HI AMPLITUDE UPR
RDG OVER THE ERN CONUS WOULD SUPPORT THE SLOWER MAJORITY...THE 00Z
GFS ENSEMBLE MEAN SUPPORTS THE OPS MODEL SCENARIO. SO WL USE A MODEL
BLEND TO REFLECT THE UNCERTAINTY.
TUE NGT...THERE REMAINS SOME UNCERTAINTY ON THE DEGREE OF DRYING/
LARGER SCALE SUBSIDENCE THAT WL FOLLOW THE DEPARTING SHRTWV/COLD
FROPA ON TUE NGT AS SOME OF THE MEDIUM RANGE MODELS SHOW AT LEAST
ANOTHER SHRTWV FOLLOWING INTO THE AREA IN THE WSW FLOW ALOFT. SO WL
MAINTAIN SOME LO CHC POPS REFLECTED IN THE MODEL CONSENSUS.
WED THRU SAT...A ZONAL FLOW OF MARITIME POLAR PACIFIC AIR IS FCST TO
DOMINATE THRU MID WEEK...WITH TENDENCY FOR AN UPR RDG TO BLD OVER
CENTRAL NAERMICA TOWARD NEXT WEEKEND. THE RESULT WL BE ABOVE NORMAL
TEMPS. ALTHOUGH A SHRTWV EMBEDDED IN THE ZONAL FLOW IS FCST TO PASS
THE UPR LKS IN THE THU/FRI TIME FRAME...LARGER SCALE ACYC FLOW ARND
HI PRES PASSING THRU ONTARIO WL HOLD DOWN PCPN CHCS. A LO PRES. MORE
RA COULD ARRIVE NEXT WEEKEND AS A LO PRES ADVANCING SLOWLY TO THE N
TOWARD THE LOWER LKS CLOSES IN ON THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1241 PM EST SAT MAR 5 2016
VFR CEILINGS AND VIS WILL BE THE RULE THROUGH THE NEXT 24HRS. THE
ONLY HOLDOUT WILL BE INITIALLY THIS AFTERNOON AS THE END OF LAKE
ENHANCED MAINLY MVFR CLOUD COVER SINKS ACROSS UPPER MI /ENDING LAST
AT IWD AND SAW BY 23Z/. HIGH PRESSURE OVER WESTERN LAKE
SUPERIOR...STRETCHING FROM S MN/IA WILL BRIEFLY TAKE HOLD OF UPPER
MI FOR THE REST OF THE AFTERNOON HOURS...BEFORE QUICKLY EXITING
ACROSS LOWER MI THIS EVENING. A STRONG PRESSURE GRADIENT WILL SET UP
ACROSS THE AREA OVERNIGHT AND REMAIN THROUGH THE DAY SUNDAY. THIS
WILL BE THE RESULT OF THE EXITING INTO THE MID ATLANTIC STATES...AND
LOW PRESSURE TRACKING ACROSS S CANADA THIS EVENING TO SLIDE ACROSS S
MANITOBA AND ND BY DAYBREAK SUNDAY. INCREASING WINDS ABOVE THE SFC
BASED INVERSION WILL LEAD TO LLWS AT KIWD LATE TONIGHT INTO EARLY
SUNDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 314 PM EST SAT MAR 5 2016
AS THE PRES GRADIENT TIGHTENS TONIGHT BETWEEN HI PRES MOVING INTO
THE MID ATLANTIC STATES AND A LO PRES CROSSING SCENTRAL CANADA...
EXPECT LIGHT WINDS THIS EVENING TO BECOME SW AND INCREASE UP TO 25-
30 KTS ON SUN AFTERNOON. NOT OUT OF THE QUESTION THERE COULD BE A
FEW GALE FORCE GUSTS TO 35 KTS OVER EASTERN LAKE SUP DURING THIS
TIME. WINDS WILL THEN DIMINISH SUN NIGHT/MON UNDER A WEAKENING PRES
GRADIENT. AS LOW PRES TRACKS FROM THE WESTERN PLAINS MON MORNING TO
NORTHERN ONTARIO TUE...EXPECT S WINDS TO INCREASE UP TO 25 KTS
AGAIN. THE ARRIVAL OF MOISTER AIR IN THIS FLOW OVER THE RELATIVELY
CHILLY LAKE WATERS WILL CAUSE SOME FOG. AS THE COLD FRONT ASSOCIATED
WITH THIS LO PRES PASSES OVER LAKE SUP ON LATE TUE INTO EARLY WED...
WINDS WILL SHIFT TO THE WNW UP TO 20-25 KTS. THE ARRIVAL OF A HI
PRES RIDGE WILL THEN CAUSE DIMINISHING WINDS LATER ON WED AND THU.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WARNING FROM 1 PM TO 10 PM EST SUNDAY FOR LMZ248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KC
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
300 PM EST SAT MAR 5 2016
.DISCUSSION...
ACCUMULATING SNOW COMING TO AN END BY 00Z...AS 700 MB COLD POOL OF
-14 TO -15 C EXITS SOUTHEAST MICHIGAN EARLY THIS EVENING AND
ANTICYCLONIC FLOW BUILDS IN...WITH WARMING MID LEVELS AND LOWERING
INVERSION HEIGHTS TONIGHT. UNCERTAINTY WITH TRAPPED LOW LEVEL
MOISTURE/LOW CLOUDS AS SURFACE HIGH PRESSURE OF 1026 MB BUILDS INTO
SOUTHEAST MICHIGAN...PROVIDING FAVORABLE BACKDROP FOR COLD (AROUND
10 DEGREES) MINS IF CLOUDS BREAK. THE RAP SOUNDINGS SUGGEST TO SKEW
THE FORECAST ON CLOUDIER SIDE FOR MUCH OF THE NIGHT...WHICH WOULD
KEEP MINS ELEVATED IN THE LOWER 20S/AROUND 20 DEGREES.
HOWEVER...CLEARING TREND WORKING DOWN FROM NORTHERN LOWER MICHIGAN
THIS AFTERNOON IS LOOKING FAIRLY AGRESSIVE...AND DO WANT TO GIVE
WEIGHT TO THE 12Z EURO WHICH ALLOWS FOR CLEARING IN NORTH HALF OF
CWA...ALLOWING MINS TO FALL INTO THE TEENS. IF CLEARING DOES EXTEND
EVEN FARTHER SOUTH TONIGHT...COULD HAVE FOG DEVELOPMENT...BUT
ELECTED TO LEAVE OUT OF THE FORECAST DUE TO THE LOW PROBABILITY OF
OCCURRENCE AT THIS TIME.
WITH UPPER LEVEL RIDGE AXIS ARRIVING TOMORROW...WARM ADVECTION
REALLY KICKS...AS 850 MB TEMPS RISE INTO THE MID SINGLE NUMBERS LATE
IN THE DAY...WITH 925 MB TEMPS PROGGED TO RISE ABOVE 0
C...SUPPORTIVE OF HIGHS IN THE LOWER 40S. ALTHOUGH...CONCERNS WITH
LOW CLOUDS PERSISTS WITH THE VERY STEEP LOW LEVEL INVERSION IN
PLACE.
CONTINUED STRONG SOUTHWEST LOW LEVEL WARM ADVECTION SUNDAY NIGHT
WITH SUFFICIENT PRESSURE GRADIENT/SURFACE WINDS TO MITIGATE FOG
POTENTIAL...DESPITE SURFACE DEW PTS RISING INTO THE 30S. 12Z
EURO/NAM BOTH INDICATING 925 MB TEMPS RISING JUST ABOVE 10
C ON MONDAY...SUGGESTIVE OF MAXES CLIMBING INTO THE LOWER 60S.
HOWEVER...UNLIKE OUR PAST WARMUP`S IN FEBRUARY...WARM ADVECTION MID
CLOUDS ARE EXPECTED TO BE A BIT THICKER/PERSISTENT...AND WILL TEMPER
THE WARMUP A BIT AND KEEP MAXES IN THE 55 TO 60 DEGREE RANGE.
ISENTROPIC ASCENT AND CONTINUED MOISTURE TRANSPORT COULD YIELD
SOME LIGHT RAIN/DRIZZLE POSSIBLY DEVELOPING AS WELL...ESPECIALLY
AS WE HEAD INTO MONDAY NIGHT.
FROM TUESDAY ONWARD...MOISTURE PLUME OF PWAT 1+ INCHES WILL CREEP
EASTWARD AHEAD OF LOWER TROPOSPHERIC FRONTAL BOUNDARY. THESE
FEATURES SHOULD REMAIN FAR ENOUGH TO THE WEST TO ENSURE MAINLY DRY
AND VERY MILD WEATHER ON TUESDAY BEFORE PRECIPITATION CHANCES
INCREASE TUESDAY NIGHT. MODELS CONTINUE TO INDICATE THE BOUNDARY
STALLING OVER LOWER MICHIGAN MIDWEEK...WITH A BACKDOOR SURFACE COLD
FRONT WORKING THROUGH THE REGION LATER WEDNESDAY...WHICH WOULD KNOCK
TEMPS DOWN BY ABOUT 10 DEGREES FOR THURSDAY. RAIN SHOWERS WILL
CONTINUE TO BE LIKELY THROUGH THURSDAY FAVORING THE SOUTHERN HALF OF
THE FORECAST AREA...AS DRIER AIR WILL FEED IN NORTH OF THE BOUNDARY.
&&
.MARINE...
HIGH PRESSURE MOVING ACROSS THE REGION WILL MAINTAIN LIGHT WINDS
TONIGHT. WINDS THEN WILL STRENGTHEN OUT OF THE SOUTHWEST ON SUNDAY
IN RESPONSE TO AN INCREASING GRADIENT IN THE WAKE OF THIS HIGH.
WINDS WILL REACH 15 TO 20 KNOTS BY AFTERNOON OVER A GOOD PORTION OF
LAKE HURON...PEAKING SUNDAY NIGHT AT 20 TO 25 KNOTS OVER THE OPEN
WATERS. AT THIS TIME...GUSTS ARE EXPECTED TO REMAIN BELOW GALE
FORCE...WITH WARMER AIR SURGING INTO THE AREA PROVIDING A HIGH
DEGREE OF STABILITY OVER THE COLD LAKE WATERS. A MODERATE SOUTH TO
SOUTHWEST WIND WILL CONTINUE THROUGH EARLY NEXT WEEK.
&&
.AVIATION...ISSUED 1253 PM EST SAT MAR 5 2016
ONGOING WIDESPREAD LIGHT SNOW IN IFR CONDITIONS WILL GRADUALLY LIFT
EASTWARD THROUGH THE LATE AFTERNOON/EARLY EVENING PERIOD. ADDITIONAL
ACCUMULATION BELOW ONE INCH. EXISTING STRATUS WILL HOLD TIGHT
THROUGH THE EVENING PERIOD...EASING INTO MVFR DURING THIS TIME.
CLOUD TRENDS BECOME MUCH LESS CERTAIN BEYOND MIDNIGHT AS THE
POTENTIAL DOES EXIST FOR DRIER AIR EXPANDING SOUTHWARD TO SUPPORT
GREATER CLEARING POTENTIAL. A MIXED SIGNAL WITHIN THE MODEL
GUIDANCE AND CURRENT SATELLITE TRENDS...AND WILL FAVOR A MORE
PESSIMISTIC/CLOUDIER FORECAST UNTIL SHORT TERM TRENDS BECOME MORE
DEFINITIVE. AN ELEMENT OF FOG A GREATER POSSIBILITY SHOULD A PERIOD
OF CLEAR SKY EMERGE OVERNIGHT.
FOR DTW...LIGHT SNOW IN IFR THROUGH 21Z...GRADUALLY IMPROVING
CONDITIONS THEREAFTER INTO THE EVENING. ADDITIONAL ACCUMULATION
LESS THAN ONE INCH. CLOUD TRENDS BECOME AN ISSUE BEYOND MIDNIGHT AS
THE EXISTING STRATUS WORKS AGAINST A DRYING ENVIRONMENT. AT THIS
TIME...IN FAVOR OF MAINTAINING A CEILING TONIGHT AND SUNDAY UNTIL
TRENDS CAN BECOME MORE DEFINITIVE MOVING FORWARD.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILINGS AOB 5000 FEET THROUGH THIS EVENING. LOW
OVERNIGHT AND SUNDAY.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
DISCUSSION...SF/DT
MARINE.......MR
AVIATION.....MR
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1253 PM EST SAT MAR 5 2016
.AVIATION...
ONGOING WIDESPREAD LIGHT SNOW IN IFR CONDITIONS WILL GRADUALLY LIFT
EASTWARD THROUGH THE LATE AFTERNOON/EARLY EVENING PERIOD. ADDITIONAL
ACCUMULATION BELOW ONE INCH. EXISTING STRATUS WILL HOLD TIGHT
THROUGH THE EVENING PERIOD...EASING INTO MVFR DURING THIS TIME.
CLOUD TRENDS BECOME MUCH LESS CERTAIN BEYOND MIDNIGHT AS THE
POTENTIAL DOES EXIST FOR DRIER AIR EXPANDING SOUTHWARD TO SUPPORT
GREATER CLEARING POTENTIAL. A MIXED SIGNAL WITHIN THE MODEL
GUIDANCE AND CURRENT SATELLITE TRENDS...AND WILL FAVOR A MORE
PESSIMISTIC/CLOUDIER FORECAST UNTIL SHORT TERM TRENDS BECOME MORE
DEFINITIVE. AN ELEMENT OF FOG A GREATER POSSIBILITY SHOULD A PERIOD
OF CLEAR SKY EMERGE OVERNIGHT.
FOR DTW...LIGHT SNOW IN IFR THROUGH 21Z...GRADUALLY IMPROVING
CONDITIONS THEREAFTER INTO THE EVENING. ADDITIONAL ACCUMULATION
LESS THAN ONE INCH. CLOUD TRENDS BECOME AN ISSUE BEYOND MIDNIGHT AS
THE EXISTING STRATUS WORKS AGAINST A DRYING ENVIRONMENT. AT THIS
TIME...IN FAVOR OF MAINTAINING A CEILING TONIGHT AND SUNDAY UNTIL
TRENDS CAN BECOME MORE DEFINITIVE MOVING FORWARD.
//DTW THRESHOLD PROBABILITIES...
* HIGH FOR CEILINGS AOB 5000 FEET THROUGH THIS EVENING. LOW
OVERNIGHT AND SUNDAY.
&&
.PREV DISCUSSION...ISSUED 959 AM EST SAT MAR 5 2016
UPDATE...
HAVE ALL BUT REMOVED FREEZING DRIZZLE MENTION...AS 700 MB COLD OF
-14 TO -15 C SLOWLY TRACKS THROUGH SOUTHEAST MICHIGAN DURING THE
REMINDER OF THE DAY SUPPORTING ALL SNOW...WITH RADAR TRENDS
SUPPORTING MORE CONVECTIVE SNOW BANDS/HIGHER RATES...AND HAVE GONE
AHEAD AND RAISED ACCUMULATIONS TO ACCOUNT FOR 2 INCH TOTALS ACROSS
WASHTENAW/LENAWEE COUNTIES...AND WITH THE SLOW MOVING CONVERGENCE
ZONE AND PROLONGED PERIOD THROUGH THE AFTERNOON HOURS...3 INCHES
CAN`T BE RULED OUT.
PREV DISCUSSION...ISSUED 826 AM EST SAT MAR 5 2016
UPDATE...
QUICK UPDATE TO RAISE POPS AND CARRY MORE SNOW (VS FREEZING
DRIZZLE BASED ON LATEST RADAR TRENDS)...AS MID LEVEL CIRCULATION
ROTATING THROUGH CENTRAL LAKE MICHIGAN/SOUTHWEST LOWER MICHIGAN
PROVIDES SUFFICIENT FORCING ON THE NORTHEAST FLANK TO SUPPORT SNOW
SHOWERS...AS IR SHOWS CLOUD TOP COOLING AND SUFFICIENT ICE NUCLEI.
THE WEAK LOW LEVEL CIRCULATION WILL SLOWLY TRACK
SOUTHEAST...EXPECTED TO MOVE THROUGH LENAWEE COUNTY AND INTO
NORTHWEST OHIO LATE THIS AFTERNOON. SHOULD BE ABLE TO GRIND OUT AT
LEAST AN INCH OF SNOW ACCUMULATION ALONG AND WEST OF U.S. 23 UP TO
ABOUT M-59. WILL HAVE TO WATCH OUT FOR LOCALIZED HIGHER AMOUNTS
IF CONVECTIVE ELEMENTS ARE MORE VIGOROUS.
PREV DISCUSSION...ISSUED 309 AM EST SAT MAR 5 2016
DISCUSSION...
LIGHT SNOW OVERSPREAD MUCH OF SE MI OVERNIGHT. SFC OBSERVATIONS AND
RADAR SUGGEST SOME LOCALS /PARTICULARLY SOUTH OF THE I-69 CORRIDOR/
HAVE BEEN EXPERIENCING INTERVALS OF FAIRLY GOOD SNOWFALL RATES. THIS
SNOW IS OCCURRING WITHIN A REGION OF MID LEVEL ISENTROPIC ASCENT
AHEAD OF AN UPPER SHORT WAVE NOW OVER WISCONSIN...AIDED BY A LEAD
SHORT WAVE IMPULSE NOW ROTATING INTO SE MI. THE UPSTREAM MID LEVEL
TROUGH WILL ROTATE INTO THE OHIO VALLEY BY AFTERNOON...WITH THE
ASSOCIATED SFC LOW /OVER CNTRL WISCONSIN AS OF 07Z/ TRACKING INTO
NRN INDIANA BY EARLY AFTERNOON. THE REGIONAL WATER VAPOR LOOP SHOWS
THE AXIS OF DEEP LAYER MOISTURE ALREADY OVER SE MI...WITH MID LEVEL
DRY AIR FAST MOVING INTO SW LOWER MI. THIS LOSS OF MID LEVEL
MOISTURE IS LEADING TO AN ABRUPT END TO THE LIGHT SNOW OVER SW LOWER
ATTM. MODEL RH PROGS AND SOUNDINGS /WITH SUPPORT FROM THE WATER
VAPOR LOOP/ INDICATE THE MID LEVEL DRY AIR WILL OVERSPREAD SE MI BY
12Z. THE RESULTING BRIEF DURATION OF THE SNOW EARLY THIS MORNING
WILL KEEP ACCUMS TO AN INCH OR LESS /WITH THE HIGHEST AMOUNTS SOUTH
OF I-69/.
DESPITE THE LOSS OF MID LEVEL MOISTURE...THERE WILL BE AN ADDITIONAL
INFLUX OF LOW LEVEL MOISTURE /SUB 850MB/ DRIVEN INTO SE MI DURING
THE MORNING. THIS WILL PROVIDE A GOOD SET UP FOR SOME FREEZING
DRIZZLE. THIS AND THE AMOUNT OF FZDZ REPORTS ACROSS WISCONSIN
SUPPORT ADDING AREAS OF FZDZ TO THE MORNING FORECAST. BY THE TIME
THAT CONDITIONS BECOME OPTIMAL FOR FZDZ...SFC TEMPS SHOULD BE
WARMING INTO THE LOWER 30S AND LIKELY ABOVE FREEZING BY NOON. THIS
AND THE POTENTIAL SHORT DURATION OF ANY DRIZZLE WILL SUPPORT HOLDING
OFF ON ANY TYPE OF WINTER WX ADVISORIES FOR THE TIME BEING.
DEEP LAYER MOISTURE WILL ROTATE BACK INTO SE MI THIS AFTERNOON. WITH
SOME STEEP MID LEVEL LAPSE RATES AND DIURNAL INSTABILITY...SNOW
SHOWER ACTIVITY IS POSSIBLE. THE NAM AND HRRR SUGGEST SOME FGEN
DEVELOPMENT ALONG THE MID TROPOSPHERIC FRONT...GENERALLY SOUTH OF
THE M 59 CORRIDOR EARLY IN THE AFTERNOON. THIS WILL NOT ONLY WARRANT
HIGHER POPS IN THESE LOCALS BUT ALSO SUGGEST SOME ADDITIONAL LIGHT
AFTERNOON SNOW ACCUMS /POSSIBLY A HALF INCH/.
SFC HIGH PRESSURE WILL EXPAND ACROSS SE TONIGHT AMIDST RISING MID
LEVEL HEIGHTS IN THE WAKE OF THE DEPARTING UPPER TROUGH. LOW LEVEL
ANTICYCLONIC FLOW AND DRY AIR ADVECTION SHOULD CLEAR THE LOW CLOUDS
OUT LATE IN THE NIGHT...SUPPORTING A BRIEF PERIOD OF DECENT
RADIATIONAL COOLING. IF THIS COOLING OCCURS A LITTLE EARLIER...LATER
SHIFTS WILL HAVE TO CONSIDER ADDING FOG TO THE FORECAST.
LONG WAVE RIDGE AMPLIFICATION ACROSS THE ERN US EARLY NEXT WEEK AND
THE ESTABLISHMENT OF STRENGTHENING SOUTHWEST FLOW FROM THE SRN
PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES WILL SUPPORT A
DRAMATIC WARM UP BEGINNING SUNDAY AND PERSISTING THROUGH AT LEAST
TUESDAY. DESPITE THE SNOW COVER...THE STRONG LOW LEVEL WARM AIR
ADVECTION WITHIN THE WELL MIXED SW FLOW WILL SUPPORT TEMPS ON THE
HIGH END OF GUIDANCE /40S SUNDAY...50S MON...60S TUES/. CONSENSUS
AMONG THE MEDIUM RANGE MODEL SUITE INDICATE BETTER RAINFALL CHANCES
MID TO LATE WEEK AS MUCH DEEPER MOISTURE GETS ADVECTED INTO THE
GREAT LAKES. A GOOD DEAL OF FCST UNCERTAINTY REVOLVES AROUND TIMING
A BACK DOOR COLD FRONT THROUGH THE AREA NEXT WEEK. MODEL SOLUTIONS
DIVERGE WITH RESPECT TO TIMING AND AMPLITUDE OF AN UPPER WAVE
TRACKING ACROSS CANADA WHICH RESULTS IN A LARGE SPREAD IN TIMING
THIS BACK DOOR COLD FRONT INTO SE MI. IT LOOKS AS THOUGH THIS FRONT
WILL MOVE THROUGH SOMETIME IN THE WED TO THURS TIME FRAME AND WILL
HAVE THE POTENTIAL TO BRING MUCH COOLER LAKE MODIFIED BOUNDARY LAYER
AIR INTO THE AREA /WITH WARM MOIST SOUTHWEST FLOW ALOFT STILL
PROVING PERIODIC CHANCES FOR RAIN SHOWERS/.
MARINE...
WINDS WILL REMAIN LIGHT TODAY...GENERALLY UNDER 10 KNOTS...AS LOW
PRESSURE SLIDES FROM THE WESTERN GREAT LAKES INTO THE OHIO VALLEY
TODAY...AND THEN A RIDGE OF HIGH PRESSURE SHIFTS INTO THE AREA
TONIGHT. LOW PRESSURE TRACKING ACROSS HUDSON BAY AND ONTARIO SUNDAY
INTO SUNDAY NIGHT WILL THEN PROVIDE A TIGHTER SURFACE PRESSURE
GRADIENT OVER THE AREA...CAUSING WINDS TO INCREASE. THE STRONGEST
WINDS LOOK TO OCCUR OVER THE OPEN WATERS OF LAKE HURON...WITH SPEEDS
INTO THE 20 TO 25 KNOT RANGE. GUSTS SHOULD REMAIN BELOW GALE FORCE
HOWEVER AS WARMER AIR SURGING INTO THE AREA WILL PROVIDE A HIGH
DEGREE OF STABILITY OVER THE COLD LAKE WATERS.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....MR
UPDATE.......SF
DISCUSSION...SC
MARINE.......HLO
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1241 PM EST SAT MAR 5 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EST SAT MAR 5 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWS A RIDGE OVER THE ROCKIES
AND A TROF OVER ERN NAMERICA. SHORTWAVE THAT BROUGHT SNOW INTO UPPER
MI OVER THE LAST 12HRS OR SO IS TRACKING SE THRU WI. THIS WILL BE
THE FINAL SHORTWAVE TO DROP SE THRU THE AREA BEFORE A TRANSITION TO
A WARM SPLIT FLOW PATTERN WITH ABOVE NORMAL HEIGHTS AND W TO SW FLOW
ACROSS THE UPPER GREAT LAKES NEXT WEEK. RADAR TRENDS OVER THE LAST
COUPLE OF HRS SHOW SNOW DIMINISHING OVER UPPER MI...AND UPSTREAM...
KDLH RADAR SHOWS VERY LITTLE PCPN REMAINING. THERE WERE OBS AND
REPORTS OF SOME -FZDZ EARLIER IN THE NIGHT OVER WRN UPPER MI AND NRN
WI AS THE HEAVIER SNOW DEPARTED. RECENTLY...THERE ARE FEWER OBS
SHOWING UNKNOWN PCPN...SO -FZDZ MAY BE DIMINISHING.
WITH SHORTWAVE CONTINUING SE TODAY...DIMINISHING PCPN WILL END FROM
NW TO SE. SOUTHERLY FLOW ON LAKE MI PERSISTS THRU MID TO LATE
MORNING WHICH SHOULD HELP WEAKLY LAKE ENHANCED SNOW TO LINGER.
THUS...HIGHEST POPS WILL PAINTED OVER THE E THIS MORNING WITH
PERHAPS ANOTHER HALF INCH OR SO OF SNOW ACCUMULATION. TO THE W...
WILL KEEP A MENTION OF -FZDZ/-SN MAINLY IN THE COUNTIES BORDERING WI
FOR THE NEXT FEW HRS. SATELLITE IMAGERY SHOWS CLEARING NOT THAT FAR
AWAY ACROSS NRN LAKE SUPERIOR. WITH HIGH PRES RIDGE BUILDING INTO
THE UPPER GREAT LAKES THIS AFTN...LOW-LEVEL NORTHERLY WINDS AHEAD OF
THE RIDGE WILL DIMINISH. THIS INCREASES THE UNCERTAINTY IN HOW MUCH
CLEARING WILL OCCUR...ESPECIALLY SINCE UPSLOPE FLOW OFF THE LAKE
UNDER A LOWERING INVERSION SHOULD GREATLY SLOW THE CLEARING PROCESS.
KEWEENAW OBVIOUSLY HAS THE BEST CHC OF AT LEAST PARTIALLY CLEARING
OUT TODAY GIVEN THE CLOSE PROXIMITY OF CLEAR SKIES ALREADY EARLY
THIS MORNING. FOR NOW...FCST WILL SHOW A VERY GRADUAL DECREASE IN
CLOUDS FROM THE N AND NW THIS AFTN INTO THIS EVENING.
CLOUD FCST INTO TONIGHT REMAINS A BIT TRICKY. IF THE EXTENSIVE LOW
CLOUDS ACROSS MN/WI PERSIST THRU THE DAY...THESE CLOUDS MAY MOVE
BACK INTO THE AREA TONIGHT ONCE S TO SW FLOW DEVELOPS/INCREASES
AFTER THE HIGH PRES RIDGE PASSES. OTHERWISE...PROVIDED MUCH OF
TODAYS CLOUD COVER DEPARTS BY EVENING...THERE WILL BE AN OPPORTUNITY
FOR TEMPS TO FALL QUICKLY THIS EVENING UNDER LIGHT/CALM WIND. LEANED
FCST TO THE COLDER BIAS CORRECTED REGIONAL/GLOBAL CANADIAN MODELS
DUE TO THEIR NORMAL SUPERIOR PERFORMANCE IN RADIATIONAL COOLING
SITUATIONS. TRADITIONAL COLD SPOTS WILL FALL DOWN INTO THE MID TEENS
IF SKIES ARE MOSTLY CLEAR THIS EVENING.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 349 AM EST SAT MAR 5 2016
ADVERTISED EARLY SPRING PREVIEW IS STILL ON TRACK FOR EARLY NEXT
WEEK AND BEYOND. SUBSTANTIAL WARM ADVECTION KICKS IN ON SUNDAY.
PRESSURE GRADIENT WILL TIGHTEN SIGNIFICANTLY BETWEEN SURFACE
LOW/SHORTWAVE MOVING THROUGH NORTHERN ONTARIO AND HIGH PRESSURE
ALONG THE EAST COAST. 85H TEMPS CLIMB INTO THE PLUS 5 TO 8C RANGE.
EVEN WITH THE STABLE THERMAL PROFILE 92H WINDS ARE FORECAST UP TO 40
KNOTS SO EXPECT WINDS TO BE PRETTY GUSTY. NAM REMAINS
CONSISTENT...AND TO A LESSER EXTENT THE GFS...IN SHOWING ENOUGH
MOISTENING THROUGH THE DAY THAT THERE MAY EVEN BE SOME LIGHT
PRECIPITATION OVER EASTERN AREAS BY LATE IN THE DAY. WILL INTRODUCE
SOME SLIGHT CHANCE POPS ACROSS THE EAST FOR SOME LIGHT RAIN/DRIZZLE.
TEMPS ON SUNDAY WILL CLIMB INTO THE 40S WEST WHILE LAKE MICHIGAN
COOLING WITH THE STRONG SOUTHWESTERLY WINDS WILL KEEP TEMPS IN THE
UPPER 30S ACROSS THE EAST.
THE BEST CHANCES FOR ANY WIDESPREAD PRECIPITATION...ALBEIT
RELATIVELY LIGHT...WILL OCCUR DURING THE MONDAY THROUGH TUESDAY
NIGHT TIME PERIOD. WHILE TEMPERATURES WILL BE WELL ABOVE NORMAL...IT
WILL PROBABLY BE PRETTY GLOOMY DURING THIS PERIOD. CONTINUED WARM
ADVECTION...DEWPOINTS CLIMBING INTO THE 30S AND 40S...AND A MELTING
SNOWPACK WILL YIELD PLENTY OF LOW CLOUDS...PATCHY FOG...AND DRIZZLE.
SHEARING OUT SHORTWAVE EJECTING WEST OF THE AREA ON TUESDAY WITH
SURFACE LOW PASSING NORTHWEST OF LAKE SUPERIOR WILL BRING THE BEST
CHANCE OF RAIN ON TUESDAY. WITH DYNAMICAL FORCING ON THE WANE AND
LINGERING MID LEVEL DRY AIR ANY PRECIPITATION WILL BE PRETTY LIGHT.
AS TRAILING COLD FRONT CROSSES THE AREA LATE TUESDAY AND WITH FAIRLY
STEEP MID LEVEL LAPSE RATES STILL CANNOT RULE THE POSSIBILITY OF A
THUNDERSTORM ALONG THE FRONT. HOWEVER...CAPPING MAY REMAIN TOO
STRONG TO ALLOW ANY DEEP CONVECTION. DESPITE THE CLOUDS
TEMPERATURES WILL APPROACH 50 FOR MANY ON MONDAY AND INTO THE 50S ON
TUESDAY AWAY FROM THE COOLING INFLUENCES OF THE LAKES...ESPECIALLY
LAKE MICHIGAN.
DRIER AIR ALONG WITH SOME COOLING BEHIND THE FRONT WILL ALLOW
PRECIPITATION TO COME TO AN END TUESDAY NIGHT.
FORECAST LOOKS DRY DURING THE WEDNESDAY THROUGH FRIDAY PERIOD. AFTER
A BRIEF COOL DOWN WEDNESDAY...ALTHOUGH STILL ABOVE NORMAL...MILD
PACIFIC AIR WILL RETURN FOR LATE IN THE WEEK WITH DAYTIME TEMPS ONCE
AGAIN APPROACHING 50 FOR MANY BY LATE IN THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1241 PM EST SAT MAR 5 2016
VFR CEILINGS AND VIS WILL BE THE RULE THROUGH THE NEXT 24HRS. THE
ONLY HOLDOUT WILL BE INITIALLY THIS AFTERNOON AS THE END OF LAKE
ENHANCED MAINLY MVFR CLOUD COVER SINKS ACROSS UPPER MI /ENDING LAST
AT IWD AND SAW BY 23Z/. HIGH PRESSURE OVER WESTERN LAKE
SUPERIOR...STRETCHING FROM S MN/IA WILL BRIEFLY TAKE HOLD OF UPPER
MI FOR THE REST OF THE AFTERNOON HOURS...BEFORE QUICKLY EXITING
ACROSS LOWER MI THIS EVENING. A STRONG PRESSURE GRADIENT WILL SET UP
ACROSS THE AREA OVERNIGHT AND REMAIN THROUGH THE DAY SUNDAY. THIS
WILL BE THE RESULT OF THE EXITING INTO THE MID ATLANTIC STATES...AND
LOW PRESSURE TRACKING ACROSS S CANADA THIS EVENING TO SLIDE ACROSS S
MANITOBA AND ND BY DAYBREAK SUNDAY. INCREASING WINDS ABOVE THE SFC
BASED INVERSION WILL LEAD TO LLWS AT KIWD LATE TONIGHT INTO EARLY
SUNDAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EST SAT MAR 5 2016
EXPECT LIGHT WINDS...MOSTLY UNDER 15KT TO BE THE RULE ACROSS LAKE
SUPERIOR TODAY UNDER A WEAK PRES GRADIENT WITH HIGH PRES RIDGE
ARRIVING IN THE AFTN. PRES GRADIENT WILL THEN TIGHTENT TONIGHT AND
SUN AS THE RIDGE SHIFTS TO THE E COAST AND A LOW PRES MOVES ACROSS
SCNTRL CANADA. S TO SW WINDS WILL RAMP UP TO AS HIGH AS 30KT LATE
TONIGHT AND SUN. NOT OUT OF THE QUESTION THAT A FEW GALE FORCE GUSTS
COULD OCCUR OVER EASTERN LAKE SUPERIOR SUN. WINDS WILL THEN DIMINISH
SUN NIGHT/MON UNDER A WEAKENING PRES GRADIENT. AS LOW PRES TRACKS
FROM THE WESTERN PLAINS MON MORNING TO NORTHERN ONTARIO TUE AND
QUEBEC WED...WINDS WILL AGAIN INCREASE TO 15-25KT AT TIMES TUE/WED.
SOME FOG MAY FORM OVER THE CHILLY WATERS MON NIGHT/TUE AS MOISTER
AIR MOVES INTO THE UPPER LAKES AHEAD OF THE LOW PRES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MZ
AVIATION...KF
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1154 AM CST SAT MAR 5 2016
.UPDATE...
ISSUED AT 1153 AM CST SAT MAR 5 2016
UPDATE TO THE FORECAST WILL ONLY HAVE MINOR ADJUSTMENTS WITH MOST
ELEMENTS ON TRACK. THE LATEST HRRR AND RAP13 SUGGEST DEWPOINTS
COULD STILL BE A COUPLE DEGREES TOO HIGH IN THE SOUTHWEST...SO
ADJUSTED THEM ACCORDINGLY. THE STRATUS HAS FINALLY EXITED THE
EAST...THOUGH THERE ARE SOME HIGH CLOUDS SPILLING INTO WESTERN
NORTH DAKOTA FROM MONTANA. WILL CARRY SCATTERED
CLOUDS...ESPECIALLY WEST THROUGH THE AFTERNOON.
UPDATE ISSUED AT 931 AM CST SAT MAR 5 2016
NO MAJOR CHANGES TO THE FORECAST WERE WARRANTED SO FAR THIS
MORNING. MAIN CHANGE WAS TO SLOW DOWN THE CLEARING FROM JAMESTOWN
EASTWARD WHERE THE CLOUDS HAVE BEEN A LITTLE SLOW TO MOVE OUT.
THE LATEST SHORT TERM MODELS STILL SHOW THE CLOUDS EXITING...WITH
ONLY SCATTERED HIGH CLOUDS LATER THIS AFTERNOON.
UPDATE ISSUED AT 646 AM CST SAT MAR 5 2016
NO SIGNIFICANT CHANGES WERE MADE WITH THIS UPDATE CYCLE...BUT WE
DID DELAY THE EXIT OF LOW CLOUDS /STRATUS/ IN THE SOUTHERN JAMES
RIVER VALLEY A BIT UNTIL MID MORNING BASED ON SATELLITE AND HRRR
TRENDS. OTHERWISE...THE 12 UTC BISMARCK SOUNDING REVEALED PLENTY
OF MID-LEVEL WARMING AND DRYING SINCE LAST EVENING...SUPPORTING
THE GOING WARM FORECAST FOR TODAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 344 AM CST SAT MAR 5 2016
WARMER...BREEZY...AND DRY CONDITIONS HIGHLIGHT THE SHORT TERM
PERIOD. SOUTHERLY WINDS/WARM AIR ADVECTION DEVELOP TODAY ACROSS
WESTERN AND CENTRAL NORTH DAKOTA. A MINOR COLD FRONT PASSES
THROUGH SATURDAY NIGHT.
THE LATEST WATER VAPOR AND IR IMAGERY LOOP INDICATE MID/UPPER
LEVEL RIDGING OVER THE NORTHERN ROCKIES THIS MORNING WITH
SCATTERED HIGH CLOUDS RIDING ATOP THE RIDGE INTO WESTERN NORTH
DAKOTA. FOG/STRATUS IMAGERY LOOP CONTINUES TO SHOW AN AREA OF LOW
CLOUDS IN THE JAMES RIVER VALLEY. THIS IS FORECAST TO EXIT BY 12Z
SATURDAY. THE TREND WILL BE FOR THE UPPER RIDGE TO SHIFT EAST AND
GRADUALLY FLATTEN/BECOME BROADER THROUGH TONIGHT...AS A PAIR OF
SHORTWAVES PUSH INTO THE RIDGE. THE FIRST SHORTWAVE IS BEST
DEFINED AT 700MB AND CURRENTLY IS LOCATED IN SOUTH CENTRAL
MONTANA. THIS WILL STEADILY MOVE INTO SOUTH CENTRAL NORTH DAKOTA
BY 00Z SUNDAY. NOT EXPECTING ANYTHING SIGNIFICANT AS THERE IS NO
SURFACE LOW REFLECTION. THIS SHORTWAVE WILL MAINLY SERVE TO
FLATTEN THE OVERALL HEIGHT FIELD/RIDGE AXIS AS IT PROPAGATES
THROUGH. THE SECOND SHORTWAVE NOW INTO SOUTHWEST BRITISH COLUMBIA
WILL SLIDE ACROSS SOUTHERN CANADA INDUCING A SURFACE LOW/COLD
FRONT IN SOUTHERN ALBERTA THIS AFTERNOON. IT WILL THEN MOVE EAST
AND GRAZE NORTH DAKOTA SATURDAY NIGHT WITH A WIND SHIFT AND WEAK
COLD AIR ADVECTION.
FOR TODAY...THE CANOPY OF THE 1000-500MB THICKNESS RIDGE HOVERS
OVER THE SOUTHWEST...RESULTING IN THE WARMEST/DRIEST AIR TO RESIDE
HERE. AFTERNOON HIGHS WILL CLIMB INTO THE MID/UPPER 60S SOUTHWEST.
ELSEWHERE EXPECT HIGHS IN THE 50S CENTRAL TO 40S FROM THE TURTLE
MOUNTAINS INTO THE JAMES RIVER VALLEY. UTILIZED A 50/50 COMBINATION
BLEND OF THE HRRR EXPERIMENTAL 2M HOURLY RH FIELD AND OFFICIAL
GRIDDED FORECAST TO YIELD MINIMUM RELATIVE HUMIDITIES IN THE 15
TO 20 PERCENT RANGE SOUTHWEST. THIS SEEMS LOGICAL GIVEN UPSTREAM
FLOW AND RELATED AIRMASS FROM FRIDAY HAVING ADVECTED IN FROM
WYOMING. THE HRRR RH FIELD VERIFIED WELL IN NORTH DAKOTA AS WELL
AS UPSTREAM IN THE LAST 24HR. WINDS TODAY WILL BE WEAKEST IN THE
FAR SOUTHWEST WHERE AFTERNOON RELATIVE HUMIDITIES WILL BE LOWEST.
WINDS WILL STEADILY INCREASE INTO THE BREEZY CATEGORY (15-25MPH)
FOR CENTRAL NORTH DAKOTA THIS AFTERNOON.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 344 AM CST SAT MAR 5 2016
ABOVE-NORMAL TEMPERATURES AND MAINLY DRY WEATHER WILL PREVAIL FOR
THE NEXT WEEK.
ON SUNDAY...DAILY RECORD HIGHS MAY FALL GIVEN 850-MB TEMPERATURES
IN THE 97.5 TO 99TH PERCENTILE FOR THIS TIME OF THE YEAR...NEARLY
FULL SUNSHINE...DRY SOILS...AND DORMANT VEGETATION...ALL OF WHICH
WILL SUPPORT EFFICIENT HEATING. WE ARE STILL CALLING FOR HIGHS IN
THE 60S F IN MOST AREAS AND A FEW 70 F READINGS ARE LIKELY ACROSS
SOUTHWEST AND SOUTH CENTRAL ND. MIXING IS FORECAST TO BE SOMEWHAT
MORE SHALLOW THAN ON SATURDAY BASED ON 00 UTC MODEL SOUNDINGS AND
THAT RAISES A BIT OF CONCERN FOR WARMING...BUT MORE THAN LIKELY
THAT WILL JUST ENSURE WINDS WILL STAY RELATIVELY LIGHT. SUNDAY IS
APT TO BE A TRULY STELLAR EARLY MARCH DAY.
THEREAFTER...A PACIFIC COLD FRONT WILL CROSS THE AREA MONDAY AS A
WEAK SHORTWAVE TROUGH EJECTS ACROSS THE REGION OUT OF A SPLITTING
TROUGH THAT WILL KEEP ITS CORE WELL SOUTH IN TX AND MEXICO. WE DO
HAVE A LOW-GRADE SHOWER CHANCE IN THE FORECAST BEHIND THE FRONT
MONDAY THROUGH EARLY TUESDAY. PROGRESSIVE...QUASI-ZONAL FLOW WILL
THEN OCCUR IN THE NORTHERN STREAM THE MIDDLE PART OF THE WEEK AND
THAT WILL YIELD MAINLY DRY WEATHER. THE 00 UTC GFS AND ECMWF BOTH
SUGGEST RIDGING REBUILDING AGAIN BY LATE WEEK....WITH THE 00 UTC
NAEFS EVEN CALLING FOR 850-MB TEMPERATURE ANOMALIES IN THE 90TH
PERCENTILE BY FRIDAY. THAT IS A SIGNIFICANT SIGNAL IN A LONG-LEAD
ENSEMBLE FORECAST...SUGGESTING HIGHS COULD ONCE AGAIN END UP WELL
INTO THE 60S F /WARMER THAN OUR CURRENT FORECAST/ BY LATE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1153 AM CST SAT MAR 5 2016
VFR CONDITIONS ARE FORECAST TO PREVAIL THROUGH THE 18Z TAF
PERIOD. THERE WILL BE SOME INCREASE IN HIGH LEVEL CLOUDS...BUT THE
MAIN STORY WILL BE WINDS. BREEZY SOUTH TO SOUTHEAST WINDS THIS
AFTERNOON ARE EXPECTED...BUT THEY SHOULD DIMINISH THIS EVENING.
&&
.FIRE WEATHER...
ISSUED AT 1153 AM CST SAT MAR 5 2016
DESPITE MINIMUM RELATIVE HUMIDITIES IN THE 15 TO 20 PERCENT
RANGE OVER SOUTHWEST NORTH DAKOTA THIS AFTERNOON...WINDS WILL NOT
BE STRONG ENOUGH FOR CRITICAL FIRE WEATHER CRITERIA TO BE MET.
SUSTAINED SOUTHERLY WINDS WILL WEAKEN THROUGH THE AFTERNOON TO
BETWEEN 10 AND 15 MPH...JUST AS RELATIVE HUMIDITIES REACH THEIR
MINIMUM. WILL CONTINUE TO MONITOR...BUT CURRENTLY DO NOT PLAN TO
ISSUE ANY HIGHLIGHTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...KS
LONG TERM...CJS
AVIATION...CK
FIRE WEATHER...CK
AREA FORECAST DISCUSSION
NWS PORTLAND OR
214 PM PST SAT MAR 5 2016
.SYNOPSIS...A FRONT WILL SPREAD RAIN ACROSS THE REGION THIS AFTERNOON
AND EVENING AND PRODUCE A BRIEF BURST OF GUSTY WINDS LATE TONIGHT.
SNOW LEVELS WILL FALL TO BELOW THE CASCADE PASSES LATE TONIGHT AND
SUNDAY. AN UPPER LEVEL TROUGH WILL CONTINUE SHOWERS FOR SUNDAY. A
WEAKER FRONT WILL BRING ADDITIONAL RAIN AND CASCADE SNOW SUNDAY NIGHT
THROUGH MONDAY MORNING. SHOWERS WILL DECREASE MONDAY NIGHT FOR A
BRIEF BREAK IN WEATHER TUESDAY MORNING. MORE WET WEATHER IS ON TAP
FOR TUESDAY THROUGH THURSDAY.
&&
.SHORT TERM...THERE IS A COMPLEX WEATHER PATTERN OFFSHORE WITH WATER
VAPOR IMAGERY SHOWING THREE DISTINCT BOUNDARIES STEMMING FROM WHAT
APPEARS TO BE A TRIPLE POINT LOW OFFSHORE THE OREGON/CALIFORNIA
BORDER. THE LOW IS LESS IDENTIFIABLE ON VISIBLE OR INFRARED IMAGERY.
LIGHT RAIN ALONG ONE OF THE BOUNDARIES BEGAN SPREADING INTO THE
SOUTHERN AND CENTRAL WILLAMETTE VALLEY EARLY THIS AFTERNOON. RADAR
IMAGERY SHOWS A BATCH OF HEAVIER RAIN OVER SW OREGON QUICKLY MOVING
NORTHWARD. THIS MORE PERSISTENT RAIN WILL MOVE FROM SOUTH TO NORTH
ACROSS NW OREGON AND SW WASHINGTON LATER THIS AFTERNOON THROUGH
TONIGHT. EXPECT 0.75 TO 1.50 INCHES OF RAIN FOR THE COAST...COAST
RANGE...AND CASCADES THROUGH EARLY SUNDAY MORNING...AND 0.40 TO 0.6
INCH FOR THE INTERIOR VALLEYS.
THE LOW WILL MOVE NORTHWARD OFFSHORE THE OREGON COAST THIS AFTERNOON
AND EVENING AND OFF OF THE WASHINGTON COAST TONIGHT...STAYING JUST
WEST OF 130W. THE SURFACE PRESSURE GRADIENT WILL TIGHTEN AS THE LOW
MOVES BY THE AREA...AND EXPECT A BRIEF BURST OF STRONG WINDS FOR THE
BEACHES AND HEADLANDS...AND SOME GUSTS TO AROUND 30 OR POSSIBLY 35
MPH FOR THE WILLAMETTE VALLEY.
THE FRONT WILL MOVE OUT OF THE AREA AROUND AROUND MIDNIGHT
TONIGHT...BUT SHOWERS WILL PERSIST THROUGH SUNDAY MORNING. SNOW
LEVELS WILL LOWER BEHIND THE FRONT AND SHOULD FALL TO NEAR THE
CASCADE PASSES...3500 TO 4000 FEET BY SUNRISE SUNDAY.
THE ATMOSPHERE WILL REMAIN UNSTABLE SUNDAY AS THE PARENT UPPER TROUGH
BECOMES NEGATIVELY-TILTED AND THE TROUGH AXIS MOVES OVER THE REGION.
THIS WILL FAVOR SHOWERS EVEN THOUGH THE AREA WILL BE BETWEEN SYSTEMS.
EXPECT AN ADDITIONAL 0.15 TO 0.4 INCH OF RAIN SUNDAY MORNING THROUGH
SUNDAY AFTERNOON WITH 1 TO 3 INCHES OF SNOW FOR THE CASCADES. THERE
MAY BE ENOUGH INSTABILITY FOR SOME ISOLATED THUNDERSTORMS TO SPROUT
OVER THE REGION.
THE NEXT SHORT WAVE WILL APPROACH FROM THE SOUTHWEST SUNDAY AFTERNOON
AND POSSIBLY FORM A 990MB SURFACE LOW OFFSHORE OF SOUTHERN OREGON
SUNDAY AFTERNOON. THIS LOW IS WEAKER AND FURTHER SOUTH THAN THE
PREVIOUS FEW LOWS...AND DO NOT EXPECT AS MUCH WIND. THE FRONT WILL
ALSO BE WEAKER WITH LESS AVAILABLE MOISTURE. SNOW LEVELS WILL REMAIN
AT OR JUST BELOW CASCADE PASSES. EXPECT AN ADDITIONAL 0.25 TO 0.60
INCH OF RAIN SUNDAY EVENING THROUGH EARLY MONDAY MORNING WITH 1 TO 3
INCHES OF NEW SNOW IN THE CASCADES.
AN UPPER TROUGH WILL MOVE OVER THE REGION MONDAY CONTINUING SHOWERS
AND A SLIGHT THREAT FOR THUNDERSTORMS. SHOWERS WILL DECREASE LATE
MONDAY NIGHT FOR A BRIEF BREAK IN RAIN EARLY TUESDAY. TJ
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...
A RATHER STRONG AND MOISTURE LADEN SYSTEM WILL MOVE INTO THE REGION
WEDNESDAY AND THURSDAY. WEATHER MODELS INDICATE THIS IS AN
ATMOSPHERIC RIVER SETUP WITH THE FRONT TAPPING INTO A MOISTURE PLUME
OF 1.1 T0 1.4 INCHES OF PRECIPITABLE WATER. INTEGRATIVE VAPOR
TRANSPORT SHOWS THE BEST CHANCE FOR HEAVY RAIN WILL BE ACROSS SW
OREGON AND NO CAL...BUT NW OREGON AND SW WASHINGTON WILL STILL GET A
DECENT SOAKING. WILL NEED TO MONITOR RIVER FORECASTS CLOSELY AS WE
GET INTO THE MIDDLE OF NEXT WEEK. TW
&&
.AVIATION... VFR ACROSS MOST OF THE REGION EARLY THIS
AFTERNOON...BUT RAIN ALREADY OCCURRING ALONG THE COAST BETWEEN
KONP AND KBOK WITH AREAS OF MVFR. COASTAL FLIGHT CONDITIONS WILL
LOWER INTO PREDOMINANT MVFR TO IFR EARLY EVENING. COLD FRONT
EXPECTED TO MOVE ACROSS THE COASTAL AREAS AROUND 04Z. IMPROVEMENT
TO AN MVFR TO VFR MIX AFTER 06Z. INLAND AREAS TO REMAIN MAINLY VFR
THROUGH 00Z THEN SHOW A MIX OF MVFR AND LOW-END VFR 00Z TO 12Z
SUN. SW-W WIND 30-40 KT AT 5000 FT MSL TONIGHT THROUGH SUN
MORNING WILL RESULT IN MOUNTAIN OBSCUREMENT AND MVFR OR WORSE
CONDITIONS FOR THE HIGHER TERRAIN. EXPECT WIND GUSTS UP TO 50 KT
ALONG THE COASTAL HEADLANDS AND 25 TO 35 KT OVER THE INTERIOR
VALLEYS 02Z TO 10Z SUN. HAVE INCLUDED LLWS FOR KAST JUST BEFORE
FRONTAL PASSAGE WITH SE SURFACE WIND 10-15 KT AND S WIND 30-40 KT
AT FL020.
KPDX AND APPROACHES...VFR THROUGH EARLY EVENING. RAIN RETURNS
AROUND 00Z SUN...BUT EAST SURFACE COMPONENT SHOULD MAINTAIN VFR
CONDITIONS. MVFR LIKELY AFTER 06Z SUN...BUT IMPROVING TO VFR BY
12Z. E TO SE SURFACE WIND SWITCHES TO S TO SW AROUND 06Z...WITH
GUSTS UP TO 30 KT. WEISHAAR
&&
.MARINE...NEXT FRONTAL SYSTEM TAKING SHAPE INSIDE 130W WITH BUOY
002 REPORTING SURFACE PRES OF 981.6 MB AT 20Z. WIND HAS BECOME
MORE SE AHEAD OF THIS DEVELOPING SYSTEM. THE 14Z RUC AND 12Z NAM
NOT QUITE AS ROBUST WITH WIND SPEEDS LATE THIS AFTERNOON THROUGH
TONIGHT. 12Z NAM AND GFS SHOW 30-35 KT BOUNDARY LAYER WIND SPEEDS
06Z SUN. NAM ALSO INDICATED JUST 35 KT AT 975 MB. WILL MAINTAIN
SOLID GALES WITH PEAK GUSTS UP TO 45 KT. STRONGEST SUSTAINED WIND
LOOKS TO BE FROM 02Z TO 08Z SUN. MODELS SHOW ANOTHER SURFACE LOW
DEVELOPING OVER THE SRN OREGON WATERS SUN AFTERNOON. THE 12Z NAM
IS FURTHER N WITH THIS SECONDARY LOW...BRINGING IT INLAND NEAR
NEWPORT 06Z MON. GFS SHOWS THE ENERGY FURTHER S...BETWEEN NORTH
BEND AND BROOKINGS. SHOULD THE NAM VERIFY...MAY NEED TO GO WITH
GALES FOR PZZ255 SUN EVENING.
CONDITIONS SETTLE DOWN A BIT LATE SUN NIGHT THROUGH MON NIGHT. THE
NEXT SYSTEM MOVES INTO THE WATERS TUE. MODELS SEEMS TO FOCUS THE
MAIN ENERGY ACROSS THE CENTRAL AND S OREGON WATERS. EAST WIND
COMPONENT TUE WILL KEEP THE STRONGEST WIND SPEEDS FURTHER
OFFSHORE AND INHIBIT THE POTENTIAL FOR COASTAL JET DEVELOPMENT.
HAVE INDICATED GALE FORCE WIND SPEEDS OVER THE OUTER WATERS TUE.
MODELS SHOW A COUPLE OF REINFORCING SURFACE LOWS TRAVELING ALONG
THE FRONTAL BOUNDARY TUE NIGHT THROUGH WED EVENING WITH STORM
FORCE GUSTS POSSIBLE SOUTH OF CASCADE HEAD WED AND WED EVENING.
ACTIVE PATTERN CONTINUES INTO NEXT WEEKEND.
SEAS HAVE SETTLED TO 10 TO 12 FT EARLY THIS AFTERNOON...BUT WILL
RAMP UP AGAIN TONIGHT. COMBINED SEAS LIKELY TO GET CLOSE TO 20 FT
12Z TO 18Z SUN...WITH A RATHER LARGE WIND-WAVE COMPONENT. SEAS
HOLD IN THE MID TO UPPER TEENS SUN AFTERNOON THROUGH MON MORNING.
WAVE HEIGHTS GET CLOSE TO 2O FT AGAIN LATE TUE NIGHT AND
WED...ESPECIALLY OVER THE SRN WATERS. WEISHAAR
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO 4 AM PST SUNDAY
FOR CENTRAL OREGON COAST-NORTH OREGON COAST.
WA...HIGH WIND WARNING FROM 4 PM THIS AFTERNOON TO 4 AM PST SUNDAY
FOR SOUTH WASHINGTON COAST.
PZ...GALE WARNING FROM 4 PM THIS AFTERNOON TO NOON PST SUNDAY FOR
COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT
60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 PM
PST SUNDAY.
&&
$$
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
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 STATE COLLEGE PA
542 PM EST SAT MAR 5 2016
.SYNOPSIS...
A WEAK CLIPPER TYPE LOW WILL BRING A BIT OF LIGHT SNOW OR FLURRIES
TO THE AREA TONIGHT. A LARGE RIDGE OF HIGH PRESSURE WILL BUILD
OVER THE EASTERN HALF OF THE CONTINENT BEGINNING SUNDAY AND
LASTING INTO THE UPCOMING WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
EVENING WATER VAPOR LOOP SHOWING A POTENT-LOOKING SHORTWAVE
DIVING FROM THE OHIO VALL INTO THE S APPALACHIANS. WEAK FORCING ON
THE NORTHERN PERIPHERY OF THIS FEATURE WILL COME THRU CENTRAL PA
OVERNIGHT...LIKELY PRODUCING NO MORE THAN SOME SPOTTY LGT SNOW OR
FLURRIES. A BLEND OF 12Z ENSEMBLE QPF AND MORE RECENT HRRR/NAM/GFS
OUTPUT SUPPORT ACCUMS OF LESS THAN AN INCH...WITH SOME PLACES
LIKELY SEEING NO ACCUM AT ALL. SREF AND LATEST HRRR SUGGEST THE
BACK EDGE OF THE LGT SNOW WILL BE EXITING THE SE COUNTIES ARND
DAWN.
OVERNIGHT LOWS AVERAGING IN THE 30S WILL BE A COUPLE OF DEGREES
EITHER SIDE OF NORMAL.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
HEIGHTS ALOFT WILL START REBOUNDING RAPIDLY SUNDAY WHICH WILL
LEAD TO IMPROVING SKIES AS DRY AIR WORKS IN FROM THE NW. HIGHS
FROM AROUND 40 IN THE NORTH TO AROUND 50 IN THE SOUTH WILL BE THE
BEGINNING OF THE MUCH ANTICIPATED BIG WARM UP THAT HAS BEEN
ADVERTISED FOR THE LAST SEVERAL DAYS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
BROAD CONSENSUS AMONG MED RANGE GUIDANCE IN A MARKED WARM UP
DURING THE FIRST HALF OF THE UPCOMING WEEK...AS AN ANOMALOUS UPPER
LVL RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND ASSOC SW FLOW
OVR PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER 12Z ECENS.
TEMPS WILL TAKE A RUN AT 70F BY WED OVR SOUTHERN PA.
MODELS ARE IN BETTER AGREEMENT ON BRINGING A QUASI-STATIONARY
FRONTAL BOUNDARY RUNNING FROM THE MISS VALLEY THRU THE GRT LKS AT
INTERFACE OF E COAST RIDGE AND PLAINS TROF THROUGH PA BY
MIDWEEK...AS HIGH PRESSURE TRACKING EASTWARD ACROSS CANADA WILL
NUDGE THE FRONT SOUTHWARD AND PIVOT IT FROM MORE OF A N-S
ORIENTATION TO A W-E DIRECTION. THIS COULD BRING THE NEXT BEST
CHANCE FOR PRECIPITATION AS WEAK WAVES COULD RIPPLE TOWARD PA
ALONG THE PORTION OF THE /WARM/ FRONT OVER THE OHIO VALLEY. GIVEN
THE STRONG WAA IT LOOKS TO BE ALL RAIN...WITH PRECIP BRACKETED
BETWEEN LATE IN THE DAY WED AND FRI. THE GFS IS MORE AGGRESSIVE
WITH ONSET OF PRECIP AND QPF AMOUNTS THAN THE ECMWF...BUT EITHER
WAY IT LOOKS TO BE A SHOWERY END TO THE WEEK AND TEMPS GRADUALLY
COOL BACK DOWN BUT REMAIN ABOVE NORMAL.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
21Z TAFS SENT.
MINOR ADJUSTMENTS MADE.
BANDS OF SNOW TO THE WEST ABOUT ON TRACK.
EARLIER DISCUSSION BELOW.
MVFR OVER THE LAURELS...VFR ELSEWHERE WILL CONTINUE INTO THE
LATE AFTERNOON HOURS BEFORE A STORM SYSTEM BRINGS AREAS OF LIGHT
SNOW OR RAIN AND MORE WIDESPREAD REDUCED CONDITIONS BY LATE
AFTERNOON INTO THE OVERNIGHT.
CONFIDENCE IN IFR IS LOW DUE TO THE DISORGANIZED NATURE OF THE
PRECIPITATION ASSOCIATED WITH THE WEAK-SPRAWLING LOW SLIDING SOUTH
OF THE REGION. BEST CHANCE WOULD SEEM TO BE OVER THE HIGHER
ELEVATIONS OF THE WEST IN NORTH...AND ONLY INTERMITTENTLY AS AREAS
OF LIGHT SNOW SLIDE EAST THIS EVENING INTO THE OVERNIGHT.
A MORE WIDESPREAD AREA OF MVFR CEILINGS IS LIKELY AFTER DARK INTO
EARLY SUNDAY AS THE STRONGEST PART OF THE SHORTWAVE ALOFT MOVES
THROUGH THE FLYING AREA WITH AREAS OF LIGHT SNOW POSSIBLY BRINGING
BRIEF REDUCTIONS IN VISIBILITY INTO THE 1-3 MILE RANGE.
EARLY MVFR CONDITIONS WILL STEADILY IMPROVE SUNDAY MORNING WITH
ALL TERMINALS EXPECTED TO BE VFR BY MID MORNING OR MID DAY.
OUTLOOK...SUNDAY-WEDNESDAY
MON-TUE...VFR/NO SIG WX.
WED...LOW CIGS/RAIN POSSIBLE NORTHWEST AS A COLD FRONT SAGS INTO
THE AIRSPACE.
THU...WIDESPREAD MVFR/IFR WITH RAIN SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD/LA CORTE
NEAR TERM...FITZGERALD/LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
446 PM EST SAT MAR 5 2016
.SYNOPSIS...
A WEAK CLIPPER TYPE LOW WILL BRING THE CHANCE FOR LIGHT RAIN OR
SNOW LATER TODAY INTO SUNDAY MORNING. A LARGE RIDGE OF HIGH
PRESSURE WILL BUILD OVER THE EASTERN HALF OF THE CONTINENT DURING
THE UPCOMING WEEK BRINGING MUCH ABOVE NORMAL TEMPERATURES STARTING
MONDAY...AND LASTING THROUGH AT LEAST MID WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE REGION IS CLOUDY AS OF MID DAY WITH TEMPERATURES GENERALLY IN
THE 30S. DEWPOINTS RANGE FROM THE SINGLE DIGITS OVER EASTERN ZONES
TO THE LOW 20S OVER THE SOUTHWEST. THIS DRY AIR IN PLACE IS DOING
A FINE JOB IN KILLING WHAT LITTLE LIGHT PRECIP HAS BEEN MOVING
INTO THE REGION WITH ONLY THE OBSERVING SITES OF THE SOUTHWEST
REPORTING SOME INTERMITTENT LIGHT SNOW.
A SPRAWLING AND WEAK LOW PRESSURE AREA IS DROPPING THROUGH THE
LOWER LAKES TOWARD WEST VIRGINIA. THE PRECIPITATION SHIELD EVEN
BACK INTO THE LOWER LAKES/OHIO VALLEY IS VERY
DISORGANIZED...LEADING TO A FORECAST WHERE THE POPS MAY BE HIGH
BUT THE QPF IS LOW.
THE HRRR AND WRF-NMM SUGGEST THE BEST CHANCE OF LIGHT PRECIP WILL
BE FROM ABOUT 21Z/4PM THROUGH ABOUT 09Z/4AM...WITH THE PERIOD FROM
ABOUT 03-06Z HAVING THE MOST OVERALL COVERAGE OF ACTUAL PRECIP IN
PROGRESS. IN GENERAL NO MORE THAN A TENTH OF AN INCH OF QPF IS
EXPECTED IN MOST AREAS.
WITH OCCASIONAL LIGHT PRECIP OVERNIGHT...PROBABLY MAINLY SNOW AS
WE COOL OFF A BIT...ACCUMS WILL REMAIN AN INCH OR LESS WITH THE
EXCEPTION OF THE LAURELS WHERE SOME WEAK OROGRAPHIC ENHANCEMENT
COULD LEAD TO AN INCH OR TWO.
OVERNIGHT LOWS AVERAGING IN THE 30S WILL BE A COUPLE OF DEGREES
EITHER SIDE OF NORMAL.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
HEIGHTS ALOFT WILL START REBOUNDING RAPIDLY SUNDAY WHICH WILL
LEAD TO IMPROVING SKIES AS DRY AIR WORKS IN FROM THE NW. HIGHS
FROM AROUND 40 IN THE NORTH TO AROUND 50 IN THE SOUTH WILL BE THE
BEGINNING OF THE MUCH ANTICIPATED BIG WARM UP THAT HAS BEEN
ADVERTISED FOR THE LAST SEVERAL DAYS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
BROAD CONSENSUS AMONG MED RANGE GUIDANCE IN A MARKED WARM UP
DURING THE FIRST HALF OF THE UPCOMING WEEK...AS AN ANOMALOUS UPPER
LVL RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND ASSOC SW FLOW
OVR PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER 12Z ECENS.
TEMPS WILL TAKE A RUN AT 70F BY WED OVR SOUTHERN PA.
MODELS ARE IN BETTER AGREEMENT ON BRINGING A QUASI-STATIONARY
FRONTAL BOUNDARY RUNNING FROM THE MISS VALLEY THRU THE GRT LKS AT
INTERFACE OF E COAST RIDGE AND PLAINS TROF THROUGH PA BY
MIDWEEK...AS HIGH PRESSURE TRACKING EASTWARD ACROSS CANADA WILL
NUDGE THE FRONT SOUTHWARD AND PIVOT IT FROM MORE OF A N-S
ORIENTATION TO A W-E DIRECTION. THIS COULD BRING THE NEXT BEST
CHANCE FOR PRECIPITATION AS WEAK WAVES COULD RIPPLE TOWARD PA
ALONG THE PORTION OF THE /WARM/ FRONT OVER THE OHIO VALLEY. GIVEN
THE STRONG WAA IT LOOKS TO BE ALL RAIN...WITH PRECIP BRACKETED
BETWEEN LATE IN THE DAY WED AND FRI. THE GFS IS MORE AGGRESSIVE
WITH ONSET OF PRECIP AND QPF AMOUNTS THAN THE ECMWF...BUT EITHER
WAY IT LOOKS TO BE A SHOWERY END TO THE WEEK AND TEMPS GRADUALLY
COOL BACK DOWN BUT REMAIN ABOVE NORMAL.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
21Z TAFS SENT.
MINOR ADJUSTMENTS MADE.
BANDS OF SNOW TO THE WEST ABOUT ON TRACK.
EARLIER DISCUSSION BELOW.
MVFR OVER THE LAURELS...VFR ELSEWHERE WILL CONTINUE INTO THE
LATE AFTERNOON HOURS BEFORE A STORM SYSTEM BRINGS AREAS OF LIGHT
SNOW OR RAIN AND MORE WIDESPREAD REDUCED CONDITIONS BY LATE
AFTERNOON INTO THE OVERNIGHT.
CONFIDENCE IN IFR IS LOW DUE TO THE DISORGANIZED NATURE OF THE
PRECIPITATION ASSOCIATED WITH THE WEAK-SPRAWLING LOW SLIDING SOUTH
OF THE REGION. BEST CHANCE WOULD SEEM TO BE OVER THE HIGHER
ELEVATIONS OF THE WEST IN NORTH...AND ONLY INTERMITTENTLY AS AREAS
OF LIGHT SNOW SLIDE EAST THIS EVENING INTO THE OVERNIGHT.
A MORE WIDESPREAD AREA OF MVFR CEILINGS IS LIKELY AFTER DARK INTO
EARLY SUNDAY AS THE STRONGEST PART OF THE SHORTWAVE ALOFT MOVES
THROUGH THE FLYING AREA WITH AREAS OF LIGHT SNOW POSSIBLY BRINGING
BRIEF REDUCTIONS IN VISIBILITY INTO THE 1-3 MILE RANGE.
EARLY MVFR CONDITIONS WILL STEADILY IMPROVE SUNDAY MORNING WITH
ALL TERMINALS EXPECTED TO BE VFR BY MID MORNING OR MID DAY.
OUTLOOK...SUNDAY-WEDNESDAY
MON-TUE...VFR/NO SIG WX.
WED...LOW CIGS/RAIN POSSIBLE NORTHWEST AS A COLD FRONT SAGS INTO
THE AIRSPACE.
THU...WIDESPREAD MVFR/IFR WITH RAIN SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
347 PM EST SAT MAR 5 2016
.SYNOPSIS...
A WEAK CLIPPER TYPE LOW WILL BRING THE CHANCE FOR LIGHT RAIN OR
SNOW LATER TODAY INTO SUNDAY MORNING. A LARGE RIDGE OF HIGH
PRESSURE WILL BUILD OVER THE EASTERN HALF OF THE CONTINENT DURING
THE UPCOMING WEEK BRINGING MUCH ABOVE NORMAL TEMPERATURES STARTING
MONDAY...AND LASTING THROUGH AT LEAST MID WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE REGION IS CLOUDY AS OF MID DAY WITH TEMPERATURES GENERALLY IN
THE 30S. DEWPOINTS RANGE FROM THE SINGLE DIGITS OVER EASTERN ZONES
TO THE LOW 20S OVER THE SOUTHWEST. THIS DRY AIR IN PLACE IS DOING
A FINE JOB IN KILLING WHAT LITTLE LIGHT PRECIP HAS BEEN MOVING
INTO THE REGION WITH ONLY THE OBSERVING SITES OF THE SOUTHWEST
REPORTING SOME INTERMITTENT LIGHT SNOW.
A SPRAWLING AND WEAK LOW PRESSURE AREA IS DROPPING THROUGH THE
LOWER LAKES TOWARD WEST VIRGINIA. THE PRECIPITATION SHIELD EVEN
BACK INTO THE LOWER LAKES/OHIO VALLEY IS VERY
DISORGANIZED...LEADING TO A FORECAST WHERE THE POPS MAY BE HIGH
BUT THE QPF IS LOW.
THE HRRR AND WRF-NMM SUGGEST THE BEST CHANCE OF LIGHT PRECIP WILL
BE FROM ABOUT 21Z/4PM THROUGH ABOUT 09Z/4AM...WITH THE PERIOD FROM
ABOUT 03-06Z HAVING THE MOST OVERALL COVERAGE OF ACTUAL PRECIP IN
PROGRESS. IN GENERAL NO MORE THAN A TENTH OF AN INCH OF QPF IS
EXPECTED IN MOST AREAS.
WITH OCCASIONAL LIGHT PRECIP OVERNIGHT...PROBABLY MAINLY SNOW AS
WE COOL OFF A BIT...ACCUMS WILL REMAIN AN INCH OR LESS WITH THE
EXCEPTION OF THE LAURELS WHERE SOME WEAK OROGRAPHIC ENHANCEMENT
COULD LEAD TO AN INCH OR TWO.
OVERNIGHT LOWS AVERAGING IN THE 30S WILL BE A COUPLE OF DEGREES
EITHER SIDE OF NORMAL.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
HEIGHTS ALOFT WILL START REBOUNDING RAPIDLY SUNDAY WHICH WILL
LEAD TO IMPROVING SKIES AS DRY AIR WORKS IN FROM THE NW. HIGHS
FROM AROUND 40 IN THE NORTH TO AROUND 50 IN THE SOUTH WILL BE THE
BEGINNING OF THE MUCH ANTICIPATED BIG WARM UP THAT HAS BEEN
ADVERTISED FOR THE LAST SEVERAL DAYS.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
BROAD CONSENSUS AMONG MED RANGE GUIDANCE IN A MARKED WARM UP
DURING THE FIRST HALF OF THE UPCOMING WEEK...AS AN ANOMALOUS UPPER
LVL RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND ASSOC SW FLOW
OVR PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER 12Z ECENS.
TEMPS WILL TAKE A RUN AT 70F BY WED OVR SOUTHERN PA.
MODELS ARE IN BETTER AGREEMENT ON BRINGING A QUASI-STATIONARY
FRONTAL BOUNDARY RUNNING FROM THE MISS VALLEY THRU THE GRT LKS AT
INTERFACE OF E COAST RIDGE AND PLAINS TROF THROUGH PA BY
MIDWEEK...AS HIGH PRESSURE TRACKING EASTWARD ACROSS CANADA WILL
NUDGE THE FRONT SOUTHWARD AND PIVOT IT FROM MORE OF A N-S
ORIENTATION TO A W-E DIRECTION. THIS COULD BRING THE NEXT BEST
CHANCE FOR PRECIPITATION AS WEAK WAVES COULD RIPPLE TOWARD PA
ALONG THE PORTION OF THE /WARM/ FRONT OVER THE OHIO VALLEY. GIVEN
THE STRONG WAA IT LOOKS TO BE ALL RAIN...WITH PRECIP BRACKETED
BETWEEN LATE IN THE DAY WED AND FRI. THE GFS IS MORE AGGRESSIVE
WITH ONSET OF PRECIP AND QPF AMOUNTS THAN THE ECMWF...BUT EITHER
WAY IT LOOKS TO BE A SHOWERY END TO THE WEEK AND TEMPS GRADUALLY
COOL BACK DOWN BUT REMAIN ABOVE NORMAL.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
MVFR OVER THE LAURELS...VFR ELSEWHERE WILL CONTINUE INTO THE
LATE AFTERNOON HOURS BEFORE A STORM SYSTEM BRINGS AREAS OF LIGHT
SNOW OR RAIN AND MORE WIDESPREAD REDUCED CONDITIONS BY LATE
AFTERNOON INTO THE OVERNIGHT.
CONFIDENCE IN IFR IS LOW DUE TO THE DISORGANIZED NATURE OF THE
PRECIPITATION ASSOCIATED WITH THE WEAK-SPRAWLING LOW SLIDING SOUTH
OF THE REGION. BEST CHANCE WOULD SEEM TO BE OVER THE HIGHER
ELEVATIONS OF THE WEST IN NORTH...AND ONLY INTERMITTENTLY AS AREAS
OF LIGHT SNOW SLIDE EAST THIS EVENING INTO THE OVERNIGHT.
A MORE WIDESPREAD AREA OF MVFR CEILINGS IS LIKELY AFTER DARK INTO
EARLY SUNDAY AS THE STRONGEST PART OF THE SHORTWAVE ALOFT MOVES
THROUGH THE FLYING AREA WITH AREAS OF LIGHT SNOW POSSIBLY BRINGING
BRIEF REDUCTIONS IN VISIBILITY INTO THE 1-3 MILE RANGE.
EARLY MVFR CONDITIONS WILL STEADILY IMPROVE SUNDAY MORNING WITH
ALL TERMINALS EXPECTED TO BE VFR BY MID MORNING OR MID DAY.
OUTLOOK...SUNDAY-WEDNESDAY
MON-TUE...VFR/NO SIG WX.
WED...LOW CIGS/RAIN POSSIBLE NORTHWEST AS A COLD FRONT SAGS INTO
THE AIRSPACE.
THU...WIDESPREAD MVFR/IFR WITH RAIN SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/GARTNER
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
125 PM EST SAT MAR 5 2016
.SYNOPSIS...
A WEAK CLIPPER TYPE LOW WILL BRING THE CHANCE FOR LIGHT RAIN OR
SNOW LATER TODAY INTO SUNDAY MORNING. A LARGE RIDGE OF HIGH
PRESSURE WILL BUILD OVER THE EASTERN HALF OF THE CONTINENT DURING
THE UPCOMING WEEK BRINGING MUCH ABOVE NORMAL TEMPERATURES STARTING
MONDAY...AND LASTING THROUGH AT LEAST MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE REGION IS CLOUDY AS OF MID DAY WITH TEMPERATURES GENERALLY IN
THE 30S. DEWPOINTS RANGE FROM THE SINGLE DIGITS OVER EASTERN ZONES
TO THE LOW 20S OVER THE SOUTHWEST. THIS DRY AIR IN PLACE IS DOING
A FINE JOB IN KILLING WHAT LITTLE LIGHT PRECIP HAS BEEN MOVING
INTO THE REGION WITH ONLY THE OBSERVING SITES OF THE SOUTHWEST
REPORTING SOME INTERMITTENT LIGHT SNOW.
A SPRAWLING AND WEAK LOW PRESSURE AREA IS DROPPING THROUGH THE
LOWER LAKES TOWARD WEST VIRGINIA. THE PRECIPITATION SHIELD EVEN
BACK INTO THE LOWER LAKES/OHIO VALLEY IS VERY
DISORGANIZED...LEADING TO A FORECAST WHERE THE POPS MAY BE HIGH
BUT THE QPF IS LOW.
THE HRRR AND WRF-NMM SUGGEST THE BEST CHANCE OF LIGHT PRECIP WILL
BE FROM ABOUT 21Z/4PM THROUGH ABOUT 09Z/4AM...WITH THE PERIOD FROM
ABOUT 03-06Z HAVING THE MOST OVERALL COVERAGE OF ACTUAL PRECIP IN
PROGRESS. IN GENERAL NO MORE THAN A TENTH OF AN INCH OF QPF IS
EXPECTED IN MOST AREAS.
WITH OCCASIONAL LIGHT PRECIP OVERNIGHT...PROBABLY MAINLY SNOW AS
WE COOL OFF A BIT...ACCUMS WILL REMAIN AN INCH OR LESS WITH THE
EXCEPTION OF THE LAURELS WHERE SOME WEAK OROGRAPHIC ENHANCEMENT
COULD LEAD TO AN INCH OR TWO.
OVERNIGHT LOWS AVERAGING IN THE 30S WILL BE A COUPLE OF DEGREES
EITHER SIDE OF NORMAL.
&&
.SHORT TERM / SUNDAY THROUGH 6 AM SUNDAY/...
HEIGHTS ALOFT WILL START REBOUNDING RAPIDLY SUNDAY WHICH WILL
LEAD TO IMPROVING SKIES AS DRY AIR WORKS IN FROM THE NW. HIGHS
FROM AROUND 40 IN THE NORTH TO AROUND 50 IN THE SOUTH WILL BE THE
BEGINNING OF THE MUCH ANTICIPATED BIG WARM UP THAT HAS BEEN
ADVERTISED FOR THE LAST SEVERAL DAYS.
&&
.LONG TERM /SUNDAY THROUGH SATURDAY/...
AFTER SOME MORNING CLOUDS...AND FLURRIES ACROSS THE FAR SE DURING
THE MORNING...LOOK FOR BRIGHTENING SKIES BUT STILL CHILLY
CONDITIONS FOR LATE SUNDAY MORNING AND SUNDAY AFTERNOON AS HIGH
PRES BUILDS IN FROM THE WEST WITH LIGHT NW SFC FLOW.
BROAD CONSENSUS AMONG MED RANGE GUIDANCE IN A MARKED WARM UP
DURING THE FIRST HALF OF THE UPCOMING WEEK...AS AN ANOMALOUS
UPPER LVL RIDGE BUILDS OVR THE E COAST. BERMUDA HIGH AND ASSOC SW
FLOW OVR PA DRAWS 8H TEMPS AS HIGH AS 12C BY MIDWEEK PER 12Z
ECENS. TEMPS WILL TAKE A RUN AT 70F BY WED OVR SOUTHERN PA.
MODELS ARE IN BETTER AGREEMENT ON BRINGING A QUASI-STATIONARY
FRONTAL BOUNDARY RUNNING FROM THE MISS VALLEY THRU THE GRT LKS AT
INTERFACE OF E COAST RIDGE AND PLAINS TROF THROUGH PA BY
MIDWEEK...AS HIGH PRESSURE TRACKING EASTWARD ACROSS CANADA WILL
NUDGE THE FRONT SOUTHWARD AND PIVOT IT FROM MORE OF A N-S
ORIENTATION TO A W-E DIRECTION. THIS COULD BRING THE NEXT BEST
CHANCE FOR PRECIPITATION AS WEAK WAVES COULD RIPPLE TOWARD PA
ALONG THE PORTION OF THE /WARM/ FRONT OVER THE OHIO VALLEY. GIVEN
THE STRONG WAA IT LOOKS TO BE ALL RAIN...WITH PRECIP BRACKETED
BETWEEN LATE IN THE DAY WED AND FRI. THE GFS IS MORE AGGRESSIVE
WITH ONSET OF PRECIP AND QPF AMOUNTS THAN THE ECMWF...BUT EITHER
WAY IT LOOKS TO BE A SHOWERY END TO THE WEEK AND TEMPS GRADUALLY
COOL BACK DOWN BUT REMAIN ABOVE NORMAL.
&&
.AVIATION /17Z SATURDAY THROUGH THURSDAY/...
MVFR OVER THE LAURELS...VFR ELSEWHERE WILL CONTINUE INTO THE
LATE AFTERNOON HOURS BEFORE A STORM SYSTEM BRINGS AREAS OF LIGHT
SNOW OR RAIN AND MORE WIDESPREAD REDUCED CONDITIONS BY LATE
AFTERNOON INTO THE OVERNIGHT.
CONFIDENCE IN IFR IS LOW DUE TO THE DISORGANIZED NATURE OF THE
PRECIPITATION ASSOCIATED WITH THE WEAK-SPRAWLING LOW SLIDING SOUTH
OF THE REGION. BEST CHANCE WOULD SEEM TO BE OVER THE HIGHER
ELEVATIONS OF THE WEST IN NORTH...AND ONLY INTERMITTENTLY AS AREAS
OF LIGHT SNOW SLIDE EAST THIS EVENING INTO THE OVERNIGHT.
A MORE WIDESPREAD AREA OF MVFR CEILINGS IS LIKELY AFTER DARK INTO
EARLY SUNDAY AS THE STRONGEST PART OF THE SHORTWAVE ALOFT MOVES
THROUGH THE FLYING AREA WITH AREAS OF LIGHT SNOW POSSIBLY BRINGING
BRIEF REDUCTIONS IN VISIBILITY INTO THE 1-3 MILE RANGE.
EARLY MVFR CONDITIONS WILL STEADILY IMPROVE SUNDAY MORNING WITH
ALL TERMINALS EXPECTED TO BE VFR BY MID MORNING OR MID DAY.
OUTLOOK...SUNDAY-WEDNESDAY
MON-TUE...VFR/NO SIG WX.
WED...LOW CIGS/RAIN POSSIBLE NORTHWEST AS A COLD FRONT SAGS INTO
THE AIRSPACE.
THU...WIDESPREAD MVFR/IFR WITH RAIN SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/RXR
AVIATION...LA CORTE