Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/19/15
AREA FORECAST DISCUSSION
NWS TUCSON AZ
900 AM MST TUE MAR 17 2015
.SYNOPSIS...THERE IS A CHANCE OF SHOWERS AND A FEW THUNDERSTORMS
TODAY THROUGH FRIDAY. DRY CONDITIONS WILL RETURN THIS WEEKEND
EXCEPT FOR A FEW LINGERING SHOWERS ACROSS THE WHITE MOUNTAINS.
DAYTIME TEMPERATURES WILL COOL TO NEAR NORMAL WEDNESDAY FOLLOWED BY
A WARMING TREND THIS WEEKEND.
&&
.DISCUSSION...THE 12Z KTWC SOUNDING SHOWS OUR PRECIPITABLE WATER
BUMPING UP TO .83 WITH SLIGHTLY HIGHER VALUES IMMEDIATELY SOUTH OF
THE AREA ON BLENDED SATELLITE ESTIMATES. STILL LOOKING AT A SIMILAR
SCENARIO TO PREVIOUS DISCUSSIONS INCLUDING A FOCUS PRIMARILY EAST OF
TUCSON TODAY WITH A REMNANT LOW LIFTING OUT OF NORTHWEST MEXICO INTO
NEW MEXICO. LATEST HRRR AND UOFA WRF-NAM TRENDS SHOW SHOWERS A
LITTLE FURTHER WEST LATER THIS AFTERNOON AND EARLY THIS EVENING
COMPARED TO PREVIOUS RUNS, SO WE`LL SPREAD ISOLATED SHOWER COVERAGE
CLOSER TO TUCSON FOR THAT TIME PERIOD. NO ADDITIONAL UPDATES
EXPECTED. PLEASE SEE THE PREVIOUS DISCUSSION BELOW FOR ADDITIONAL
DETAILS.
&&
.AVIATION...VALID THRU 18/18Z.
A WEAK LOW LIFTING FROM NORTHWEST MEXICO INTO NEW MEXICO WILL BRING
A CHANCE OF SHOWERS AND THUNDERSTORMS MAINLY EAST OF KTUS THIS
AFTERNOON AND EVENING. AFTER A BREAK OVERNIGHT, AN APPROACHING
SYSTEM FROM THE WEST WILL BRING ANOTHER CHANCE OF SHOWERS WEDNESDAY.
GUSTY WINDS POSSIBLE WITH OUTFLOWS, BUT IN GENERAL EXPECT NORMAL
DIURNAL WIND TRENDS. AVIATION DISCUSSION NOT UPDATED FOR TAF
AMENDMENTS.
&&
.FIRE WEATHER...THERE IS A CHANCE OF SHOWERS AND A FEW THUNDERSTORMS
MAINLY EAST OF TUCSON TODAY. MORE WIDESPREAD COVERAGE OF SHOWERS AND
THUNDERSTORMS IS EXPECTED WEDNESDAY AND THURSDAY AS A STORM SYSTEM
APPROACHES FROM THE WEST AND MOVES EASTWARD ACROSS THE AREA. THERE
WILL BE A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS FRIDAY BEFORE
THE SYSTEM MOVES EAST OF THE REGION. DRY CONDITIONS WILL RETURN THIS
WEEKEND EXCEPT FOR A FEW LINGERING SHOWERS IN THE WHITE MOUNTAINS.
GUSTY AND ERRATIC WINDS MAY OCCUR NEAR THUNDERSTORMS.
&&
.PREV DISCUSSION...UNSETTLED WORK WEEK IN STORE FOR SOUTHEAST
ARIZONA WITH THE AREA SEEING MOSTLY LIGHT PRECIPITATION AS A PAIR OF
WEATHER SYSTEM IMPACTS THE AREA. THIS FIRST ONE...CURRENTLY MOVING
THROUGH NRN MEXICO...HAS SPREAD MOISTURE INTO SE AZ. LATEST BLENDED
PRECIPITABLE WATER IMAGERY SHOWED VALUES OF 0.50" TO 0.65" WITH
SURFACE DEWPOINTS MOSTLY IN THE LOW TO MID 40S. BEST CHANCE FOR
SHOWERS AND EVEN A THUNDERSTORM OR TWO THIS AFTERNOON INTO THIS
EVENING WILL BE ACROSS GREENLEE...GRAHAM AND COCHISE COUNTIES. WITH
MOISTURE IN PLACE THE SECOND SYSTEM COMING IN FROM THE PACIFIC WILL
BRING A BETTER CHANCE OF PRECIPITATION ACROSS MOST OF THE FORECAST
AREA LATE WEDNESDAY INTO FRIDAY. A FEW AFTERNOON THUNDERSTORMS ARE
ALSO POSSIBLE. SNOW LEVELS WILL REMAIN RATHER THRU THE WEEK WITH
SOME ACCUMULATION ABOVE 8500 FEET IN THE WHITES. TEMPERATURES THIS
WEEK WILL REMAIN ABOVE NORMAL.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
MEYER/RASMUSSEN
AREA FORECAST DISCUSSION
NWS RENO NV
123 PM PDT TUE MAR 17 2015
.SYNOPSIS...
A FEW AFTERNOON SHOWERS AND THUNDERSTORMS ARE FORECAST WEDNESDAY
OVER THE SIERRA FROM ABOUT TAHOE SOUTHWARD. DRY AIR WILL THEN
OVERSPREAD THE REGION THURSDAY AND FRIDAY ALONG WITH WARMING
TEMPERATURES. GUSTY WINDS FRIDAY AFTERNOON AND EVENING WILL BE
ACCOMPANIED BY A CHANCE OF LIGHT RAIN OVER NORTHEAST CALIFORNIA. A
COLDER PACIFIC STORM MAY BRING LIGHT PRECIPITATION AND GUSTY WINDS
MONDAY AND TUESDAY.
&&
.SHORT TERM...
PRONOUNCED PLUME OF MOISTURE CONTINUES TO STREAM INTO CENTRAL NV
THIS AFTERNOON. NOT MUCH SHOWING UP ON RADAR AT THIS TIME. BUT
LATEST HRRR GUIDANCE DOES SUGGEST A FEW SHOWERS DEVELOPING OVER
MONO/MINERAL COUNTIES THROUGH EARLY EVENING, MAINLY SOUTH OF A
MAMMOTH-HAWTHORNE LINE. THIS SEEMS REASONABLE AND WILL KEEP
ISOLATED SHOWERS IN THE FORECAST. MINIMAL IMPACTS WITH SNOW LEVELS
8500+ FT.
TOMORROW COULD END UP BEING A RATHER INTERESTING WEATHER DAY,
WITH THUNDERSTORM POTENTIAL ABOUT A MONTH OR TWO EARLY!
COMBINATION OF RESIDUAL MOISTURE FROM THAT PLUME, DESTABILIZATION,
AND APPROACHING UPPER TROUGH SHOULD BE ENOUGH TO KICK OFF SHOWERS
AND A FEW TSTMS OVER THE SIERRA FROM ABOUT I-80 SOUTHWARD.
STEERING FLOW IS LIGHT THOUGH GENERALLY N/NE SUCH THAT CELLS WOULD
MOVE OVER TO THE WEST SLOPES BUT SLOWLY. ACCORDINGLY THE SREF TSTM
GUIDANCE PAINTS THE BEST CHANCES ALONG/WEST OF THE CREST. WE`VE
INCREASED CHANCES OF TSRA FOR TOMORROW AFTERNOON AND EVENING BUT
KEPT THEM PRETTY CLOSE TO THE HIGH TERRAIN. SNOW LEVELS LOOK TO BE
8000-9000 FT BASED ON WET BULB ZERO GUIDANCE, BUT THOSE COULD BE
DRAGGED DOWN 1000+ FEET IN TSTMS LEADING TO LOCALIZED RAPID SNOW
ACCUMS ON PASS ROADS.
WARMING HIGH PRESSURE THEN BUILDS IN THURSDAY ACCOMPANIED BY SOME
PRETTY DRY AIR, SEEN IN THE GFS. THIS AIR WILL LIKELY MIX DOWN TO
VALLEYS LEADING TO LOW AFTERNOON HUMIDITIES BOTH THURSDAY AND
FRIDAY AFTERNOONS. POOR MIDSLOPE AND RIDGE RH RECOVERIES ARE
ANTICIPATED THURSDAY AND FRIDAY MORNINGS AS WELL. GUIDANCE SHOWING
A COLD FRONT APPROACHING THE REGION LATE FRIDAY WHICH WILL ACT TO
KICK UP THE WINDS FRIDAY AFTERNOON AND EVENING. NOT A BIG WIND
MAKER BUT POTENTIAL IS THERE FOR GUSTS 30+ MPH ESPECIALLY FROM
HIGHWAY 50 NORTHWARD. THE COMBINATION OF THE DRY AIRMASS AND GUSTY
WINDS IS WORTH NOTING FOR OUR FIRE PARTNERS. CS
.LONG TERM (SATURDAY-TUESDAY)...
PROGRESSIVE FLOW WILL CONTINUE INTO THE WEST COAST WITH THE MAIN
STORM TRACK DIRECTED AT THE PACIFIC NORTHWEST. A SYSTEM WILL PASS
TO THE NORTH SATURDAY MORNING WHICH COULD BRING A FEW SHOWERS
NORTH OF SUSANVILLE TO GERLACH.
NEXT SYSTEM OF NOTE SHOULD REACH THE WEST COAST BY MONDAY
MORNING, THOUGH THIS LOW DOES HAVE ENOUGH DEPTH TO PUSH A FRONT
INTO NORTHERN CALIFORNIA. MODELS VARY IF PRECIPITATION WILL REACH
THE RENO-TAHOE AREA, BUT WE DO HAVE CONFIDENCE IN AT LEAST LIGHT
PRECIPITATION REACHING LASSEN AND PLUMAS COUNTIES. SNOW LEVELS
COULD BE AS LOW AS 5000 FEET, BUT THE AMOUNTS WILL REMAIN ON THE
LIGHT SIDE AS MODELS ARE FORECASTING LESS THAN 0.50 INCH OF LIQUID
THROUGH MONDAY NIGHT. WINDS WILL ALSO INCREASE WITH THIS SYSTEM,
WITH PEAK VALLEY GUSTS OF 30-40 MPH POSSIBLE. BRONG
&&
.AVIATION...
A FEW VERY LIGHT SHOWERS ARE POSSIBLE SOUTH OF MONO LAKE-
HAWTHORNE THROUGH 02Z. A FEW PATCHES OF FOG MAY DEVELOP IN THE
NORTHERN SIERRA TONIGHT, BUT OVERALL CONDITIONS WILL BE VFR
TONIGHT.
FOR WEDNESDAY, SHOWERS AND EVEN AN ISOLATED THUNDERSTORMS SHOULD
DEVELOP ALONG THE SIERRA CREST FROM PORTOLA TO MAMMOTH MOUNTAIN.
BRIEF MVFR CONDITIONS WITH A MIX OF RAIN AND SNOW PELLETS ARE
POSSIBLE AFTER 21Z. BRONG
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS RENO NV
815 AM PDT TUE MAR 17 2015
.UPDATE...
BASED ON RADAR TRENDS AND LATEST HRRR GUIDANCE WILL INCREASE
FORECAST SHOWER COVERAGE OVER MONO/MINERAL COUNTIES THROUGH THE
EARLY EVENING HOURS. SLOW MOVING PLUME OF MOISTURE COUPLED WITH SOME
DESTABILIZATION WILL RESULT IN RENEWED SHOWER DEVELOPMENT IN THESE
AREAS. AREAS ABOVE 9000 FEET, INCLUDING AROUND MAMMOTH AND THE WHITE
MOUNTAINS, COULD PICK UP A FEW INCHES OF SNOW ACCUMULATION IN
SHOWERS. NOT ANTICIPATING ANY IMPACTS TO TRAVEL ON PRIMARY HIGHWAYS.
FOR AVIATION INTERESTS, TERRAIN OBSCURATION AND LOCALIZED MVFR
CEILINGS/VISIBILITY POSSIBLE NEAR SHOWERS. REST OF FORECAST
UNCHANGED. CS
&&
.SYNOPSIS...
A FEW AFTERNOON SHOWERS WILL BE POSSIBLE IN THE SIERRA SOUTH OF
HIGHWAY 50 TODAY THROUGH THURSDAY. OTHERWISE, DRY CONDITIONS
PREVAIL UNTIL LOW CHANCES FOR PRECIPITATION RETURN BRIEFLY
SATURDAY. CONDITIONS BECOME DRIER AGAIN FOR THE BEGINNING OF NEXT
WEEK. TEMPERATURES WILL REMAIN ABOVE AVERAGE THROUGH THE WEEKEND.
&&
.SHORT TERM...
NO MAJOR SHIFTS WERE MADE TO THE PREVIOUS FORECAST. SOME LOW
CHANCES OF RAIN WILL BE POSSIBLE TODAY NORTH OF I-80 ALONG THE
TAIL END OF AN ELONGATED VORTICITY LOBE THAT CONTINUES TO EXIT THE
REGION. ADDITIONALLY, LOW CHANCES OF AN AFTERNOON SHOWER COULD
OCCUR FOR THE SIERRA SOUTH OF HIGHWAY 50 AS A WEAK UPPER LOW
SETTLES OVER CENTRAL NEVADA. THIS BAGGY TROUGH WILL PROVIDE
CONDITIONAL INSTABILITY NEEDED FOR AFTERNOON SHOWERS INTO
WEDNESDAY AS WELL. SOME ISOLATED THUNDERSTORMS WILL BE POSSIBLE
IN THE AFTERNOON ON WEDNESDAY, BUT FORCING MECHANISMS ARE WEAK,
RELYING MAINLY ON SURFACE INSTABILITY FOR CELL INITIATION. ALSO,
UPDRAFTS IN ANY CELLS THAT DO FORM WILL NOT BE STRONG AND PRONE TO
COLLAPSING ONCE CELLS MOVE AWAY FROM THEIR SOURCE. THE PRIMARY MODE
WILL BE GENERAL VARIETY WITH A SLOW WESTWARD MOTION. THESE MOTIONS
WILL KEEP THE POTENTIAL FOR THUNDERSTORMS OVER THE HIGHER TERRAIN
OF THE CENTRAL SIERRA AND OUT OF THE SIERRA FRONT.
OTHERWISE, TEMPERATURES CONTINUE TO BE UNSEASONABLY WARM WITH
HIGHS IN THE UPPER 60S TO AROUND 70 IN WESTERN NEVADA AND
MID/UPPER 50S TO AROUND 60 FOR SIERRA VALLEYS. WINDS WILL
GENERALLY GUST TO AROUND 20 MPH FOR THIS AFTERNOON FOR MOST
LOCATIONS WITH SOME HIGHER GUSTS AROUND 25 MPH POSSIBLE. WINDS
BECOME LIGHT FROM THE NORTHEAST BY WEDNESDAY; COULD SEE SOME
SLIGHTLY HIGHER WINDS, UP TO 20 MPH, IN SOUTHERN MINERAL COUNTY
WHICH TYPICALLY RESPONDS TO NORTHERLY WINDS. BENIGN CONDITIONS
EXPECTED FOR THURSDAY. BOYD
.LONG TERM...FRIDAY THROUGH MONDAY...
FEW CHANGES MADE TO THE LONG TERM WITH A ZONAL, PROGRESSIVE FLOW
WITH THE JET MORE INTO OREGON. MODELS IN DECENT AGREEMENT AND HAVE
ALL TRENDED DRIER OVERALL FROM FRIDAY THROUGH MONDAY. THEY ARE NOW
TAKING THE SYSTEMS MORE INTO WA/OR WITH MAINLY JUST AN INCREASE IN
WINDS FOR NORTHEAST CALIFORNIA AND WESTERN NV FRIDAY AND MONDAY.
THE FIRST SYSTEM FOR FRIDAY NIGHT INTO SATURDAY IS MOVING INTO
OREGON WITH THE COLD FRONT NOT PENETRATING MUCH INTO CA/NV. HAVE
CONTINUED TO TREND POPS BACK WITH ANY CHANCE OF SHOWERS MAINLY
CONFINED NORTH OF I-80. WINDS WILL INCREASE SOME, BUT IT WILL BE
BREEZY AT MOST WIND THE STRONGEST WINDS AT 700 MB, AND THEN ONLY
30-35 KTS, ARRIVE 06-12Z. GUSTS TO 30 MPH POSSIBLE FRIDAY AND
SATURDAY WITH THE SYSTEM. TEMPERATURES WILL BE MILD FRIDAY AND COOL
5-10 DEGREES SAT, BUT STILL REMAIN ABOVE NORMAL.
SOME RIDGING SUNDAY WITH LIGHT WINDS AND CONTINUED COOLER TEMPS
BEFORE THE NEXT SYSTEM MAY ARRIVE LATE MONDAY INTO TUESDAY. MODELS
HAVE TRENDED SLOWER AND FURTHER NORTH WITH IT SO HAVE SLOWED DOWN
THE ARRIVAL OF ANY PRECIP TO MONDAY NIGHT. WINDS WILL INCREASE
MONDAY AFTERNOON, BUT AGAIN DO NOT LOOK OVERLY STRONG WITH PEAK
GUSTS 30-35 MPH IN THE VALLEYS. THIS SYSTEM MAY BE COLDER IF IT
COMES IN FAR ENOUGH SOUTH, BUT GIVEN THE OVERALL PATTERN OF THE
MODELS INITIALLY TOO FAR SOUTH, WILL WAIT AND SEE. WALLMANN
&&
.AVIATION...
PRIMARILY VFR CONDITIONS TODAY WITH MID AND HIGH CLOUDS SLOWLY
EXITING AFTER 20Z. A FEW SHOWERS REMAIN POSSIBLE NORTH OF
KSVE-GERLACH BUT STILL EXPECT CIGS TO BE AOA 4 KFT UNTIL SHOWERS END
BY 20Z. WINDS TO BE SW AGAIN THIS AFTERNOON WITH PEAK GUSTS NEAR 20
KTS. VFR CONDITIONS TONIGHT WITH LIGHT WINDS AND A 30 PCT CHANCE OF
SHALLOW FZFG AT KTRK AFT 10Z. WALLMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS NEW YORK NY
732 AM EDT TUE MAR 17 2015
.SYNOPSIS...
LOW PRESSURE WILL PASS THROUGH NORTHERN NEW ENGLAND THIS
MORNING...DRAGGING A STRONG COLD FRONT ACROSS THE AREA. HIGH
PRESSURE BUILDS IN FROM THE UPPER MIDWEST TUESDAY NIGHT THROUGH
THURSDAY. A COASTAL LOW PRESSURE SYSTEM MAY IMPACT THE AREA
FRIDAY INTO FRIDAY NIGHT...FOLLOWED BY A COLD FRONT PASSAGE LATE
SATURDAY. HIGH PRESSURE BUILDS TOWARDS THE REGION FROM THE GREAT
LAKES SUNDAY INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST RADAR TRENDS AS WELL AS HRRR AND RAP TRENDS INDICATE LIGHT
RAIN WILL CONTINUE TO DEVELOP AND OVERSPREAD MUCH OF THE REGION
EARLY THIS MORNING. HAVE INCREASED POPS WITH THIS UPDATE TO INCLUDE
LIKELY POPS FOR ALL EXCEPT THE FAR SW CORNER OF THE CWA THROUGH ABOUT
14Z. HIGHEST POPS SHIFT TO SE CT AND EASTERN LONG ISLAND LATE THIS
MORNING WITH RAIN ENDING BY EARLY AFTERNOON.
THE LIGHT RAIN IS IN RESPONSE TO A SHORTWAVE TRACKING ACROSS THE SRN
PORTION OF THE SE CANADIAN PROVINCES EARLY THIS MORNING. SFC LOW
PRES IS DEVELOPING IN RESPONSE TO THIS AND WILL TRACK ACROSS NRN
NEW ENGLAND THIS MORNING...DRAGGING A STRONG COLD FRONT THROUGH
THE AREA.
NW WINDS WILL INCREASE BEHIND COLD FRONT DUE TO THE COMBINATION OF
STRONG CAA AND A TIGHTENING PRES GRADIENT BETWEEN RAPID
INTENSIFICATION OF THE OFFSHORE LOW TO THE NE AND STRONG CANADIAN
HIGH PRES BUILDING TO THE W. WINDS ARE EXPECTED TO RANGE FROM 15
TO 25 MPH WITH GUSTS 40 TO 45 MPH. WE ARE CLOSE TO WIND ADVSY BUT
FALL JUST SHORT...ALTHOUGH SOME OF THE MORE EXPOSED AREAS COULD
REACH IT.
HIGHS ARE CHALLENGING TODAY. THINK THE MAVS ARE WAY TOO HIGH WITH
THE CLOUD COVER...PCPN AND COLD FRONT COMING THROUGH BETWEEN 15Z
AND 18Z. SO CHOSE TO BLEND THE COOLER GUIDANCE. HIGHS WILL DEPEND
ON HOW QUICKLY COLDER AIR STARTS FILTERING IN...WHICH MODELS ARE
IN GOOD AGREEMENT ABOUT BEING AROUND 18Z.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TIGHT PRES GRADIENT REMAINS ACROSS THE REGION INTO WED BEFORE
FINALLY STARTING TO RELAX DURING WED AFTN. GUSTY NW WINDS WILL
CONTINUE DURING THIS TIME...ALTHOUGH THE STRONGEST WINDS WILL HAVE
PASSED.
DEEP NW FLOW WILL SEND WEAK SHORTWAVES THROUGH THE FLOW AS WELL.
MODELS ARE HINTING AT SCT SHOWER ACTIVITY TO THE N AND W OF THE
AREA...BUT NOT CONVINCED IT WILL MAKE IT OVER THE MOUNTAINS DUE TO
DOWNSLOPING. THEREFORE HAVE INCREASED CLOUDS...BUT HAVE KEPT THE
FORECAST DRY.
LOWS TONIGHT WILL BE WELL BELOW NORMAL...RANGING FROM UPPER TEENS
TO AROUND 20 INLAND...LOWER TO MID 20S AT THE COAST...EXCEPT MID
TO UPPER 20S IN THE NYC METRO. THIS IS ABOUT 10 DEGREES BELOW
NORMAL. HIGHS WED WILL CONTINUE TO BE BELOW NORMAL RANGING FROM
MID 30S TO LOWER 40S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
CANADIAN HIGH PRESSURE BUILDS OVERHEAD ON THURSDAY WITH WEAK UPPER
LEVEL RIDGING. COLD AND DRY WEATHER CONTINUES WITH TEMPERATURES NEAR
TEN DEGREES BELOW NORMAL FOR THIS TIME OF YEAR.
ATTENTION THEN TURNS TO ENERGY WITHIN THE NORTHERN BRANCH OF THE
UPPER JET DIGGING INTO THE NORTHERN STATES. THIS ENERGY WILL
FAST APPROACH ON FRIDAY SPAWNING A LOW PRESSURE OFF THE MIDDLE
ATLANTIC COAST. THERE STILL IS A FAIRLY LARGE SPREAD AMONG THE
MEDIUM RANGE OPERATIONAL MODELS AND ENSEMBLES ON THE TIMING AND
AMPLITUDE OF THIS ENERGY. THIS LEADS TO TRACK AND STRENGTH
DIFFERENCES WITH THE DEVELOPING LOW PRESSURE. THE GFS AND ITS
ENSEMBLES CONTINUE TO BE FURTHEST SOUTH WITH THE LOW KEEPING THE
HEAVIEST PRECIPITATION SOUTH OF LONG ISLAND. THE EURO AND CMC ARE
FURTHER NORTH WITH THE LOW BRINGING MORE SUBSTANTIAL PRECIPITATION
FRIDAY INTO AT LEAST THE FIRST PART OF FRIDAY NIGHT. WITH THERE
STILL REMAINING A FAIRLY LARGE SPREAD BEING DEPICTED BY THE 00Z
MODELS...HAVE OPTED TO STAY WITH HIGH CHANCE POPS FOR THIS FORECAST
PACKAGE.
COMPLICATED PTYPE FORECAST AS THE COLD AIR SOURCE FROM THE SURFACE
HIGH PRESSURE SHIFTS OFFSHORE DURING THE DAY FRIDAY ALLOWING SURFACE
WINDS TO BECOME EAST OR EVEN SOUTHEAST WARMING THE BOUNDARY LAYER.
SOME MID LEVEL WARMTH IS ALSO POSSIBLE FURTHER COMPLICATING THE
PTYPE...HAVE MAINTAINED CONSISTENT WORDING FROM PREVIOUS FORECAST OF
RAIN AND SNOW DUE TO CONTINUED UNCERTAINTY IN THERMAL PROFILES.
THE LOW QUICKLY MOVES OFFSHORE LATE FRIDAY NIGHT FOLLOWED BY THE
APPROACH OF ANOTHER COLD FRONT ON SATURDAY. TEMPERATURES MAY
APPROACH NORMAL LEVELS BRIEFLY ON SATURDAY AHEAD OF THE FRONT.
CURRENTLY FORECASTING SLIGHT CHANCE POPS WITH THE FRONT PASSAGE
SATURDAY NIGHT. CANADIAN HIGH PRESSURE THEN BUILDS INTO THE REGION
SUNDAY INTO MONDAY WITH TEMPERATURES FALLING BACK BELOW NORMAL.
TEMPERATURES SHOULD AVERAGE AROUND TEN DEGREES BELOW NORMAL SUNDAY
INTO MONDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
LOW PRES PASSING NORTH OF THE AREA WILL DRAG A COLD FRONT ACROSS
THE REGION EARLY THIS AFTERNOON.
RAIN THIS MORNING WITH OCNL MVFR CONDS ACROSS ALL TERMINALS...AND
LOCAL IFR CONDS ACROSS NORTHERN TERMINALS.
RAIN ENDS FROM 14-16Z WITH PASSAGE OF COLD FRONT AND CONDS IMPROVE
TO VFR.
WINDS VEER TO THE NW AND INCREASE TO 15-20 KT WITH 20-30 KT GUSTS
LATE THIS MORNING...AND THEN TO 20-25 KT WITH 30-35 KT GUSTS THIS
AFTERNOON. WINDS GRADUALLY DIMINISH TONIGHT...AND THEN INCREASE
AGAIN WEDNESDAY MORNING.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM THE LEFT OF 310 MAG TO THE RIGHT AND FOR
STRENGTH OF WINDS.
KLGA FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM THE LEFT OF 310 MAG TO THE RIGHT AND FOR
STRENGTH OF WINDS.
KEWR FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM THE LEFT OF 310 MAG TO THE RIGHT AND FOR
STRENGTH OF WINDS.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM SW TO NW AND FOR STRENGTH OF WINDS.
KHPN FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM SW TO NW AND FOR STRENGTH OF WINDS.
KISP FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM SW TO NW AND FOR STRENGTH OF WINDS.
OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...
.WEDNESDAY...VFR. NW WINDS 15-20 KT WITH GUSTS UP TO 30 KT.
.WEDNESDAY NIGHT...VFR. DIMINISHING WINDS.
.THURSDAY...VFR. NW WINDS 10-15 KT.
.FRIDAY...IFR POSSIBLE IN SN AND RA.
.SATURDAY...VFR.
&&
.MARINE...
BASED ON THE LATEST SOUNDINGS WHICH ARE IN GOOD AGREEMENT...HAVE
UPGRADED ALL OF THE NON-OCEAN WATERS TO A GALE WARNING. WHILE
MIXING MAY NOT BE AS HIGH AS INDICATED DUE TO THE COLD
WATERS...THE LEVEL OF 35 KT WINDS IS FAIRLY LOW IN THE SOUNDINGS.
THE WARNING BEGINS AT 18Z ALTHOUGH IT COULD BE A FEW HOURS LATER
DEPENDING ON HOW QUICKLY THE COLDER AIR STARTS FILTERING IN. HAVE
THE WARNING ENDING AT 10Z TONIGHT...ALTHOUGH IT MAY NEED TO BE
CONTINUED ON THE OCEAN WATERS INTO WED. IT IS MARGINAL WED MORNING
SO DIDN`T HAVE THE CONFIDENCE TO GO ANY FURTHER. SCA WILL LIKELY
BE NEEDED OTHERWISE WITH A GUSTY NW FLOW CONTINUING.
WINDS AND SEAS FALL BELOW SCA LEVELS WEDNESDAY NIGHT AS HIGH
PRESSURE BUILDS OVER THE WATERS. THESE CONDITIONS ARE EXPECTED TO
CONTINUE THROUGH FRIDAY MORNING LOW PRESSURE THEN DEVELOPS OFF THE
MIDDLE ATLANTIC COAST FRIDAY INTO FRIDAY NIGHT. WINDS SHOULD
CONTINUE TO STAY JUST BELOW SCA LEVELS...BUT SEAS MAY BUILD SCA
LEVELS ON THE OCEAN FRIDAY NIGHT INTO SATURDAY.
&&
.HYDROLOGY...
LESS THAN 1/4 INCH OF RAIN IS EXPECTED THIS MORNING. HIGHEST AMOUNTS
WILL BE CONFINED TO THE SRN CT...AND THE TWIN FORKS OF LI.
THE POTENTIAL EXISTS FOR 1/2 TO 1 INCH OF LIQUID EQUIVALENT ON
FRIDAY INTO FRIDAY NIGHT. SOME OF THIS MAY FALL IN THE FROZEN
STATE BEFORE CHANGING OVER TO LIQUID.
RECENT INCREASED FLOW ON RIVERS/STREAMS...PARTICULARLY ACROSS THE
LOWER HUDSON VALLEY AND SOUTHERN CT...COUPLED WITH MILD
TEMPERATURES...MAY CAUSE ICE BREAKUP/MOVEMENT INTO EARLY THIS
WEEK. THIS SHOULD MAKE ICE JAMS AND LOCALIZED FLOODING POSSIBLE.
ICE JAM FLOODING IS UNPREDICTABLE AND SUDDEN...SO INTERESTS ALONG
ICE COVERED RIVERS SHOULD MONITOR NWS FORECASTS FOR THE LATEST
INFORMATION.
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 WEB SITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...GALE WARNING FROM 2 PM THIS AFTERNOON TO 6 AM EDT WEDNESDAY
FOR ANZ330-335-338-340-345-350-353-355.
&&
$$
SYNOPSIS...24/DS
NEAR TERM...24/DS
SHORT TERM...24
LONG TERM...DS
AVIATION...MPS
MARINE...24/DS
HYDROLOGY...24/DS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
729 AM EDT TUE MAR 17 2015
.SYNOPSIS...
SHOWERS ANTICIPATED AHEAD OF AN ARCTIC FRONT...WHICH WILL SWEEP
ACROSS SOUTHERN NEW ENGLAND THIS AFTERNOON. BLUSTERY AND
UNSEASONABLY COLD WEATHER WILL FOLLOW INTO THURSDAY. A WINTER
STORM MAY IMPACT OUR REGION LATE FRIDAY INTO SATURDAY.
OTHERWISE...DRY AND UNSEASONABLY COLD WEATHER EXPECTED FOR EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
730 AM UPDATE...
ONLY MINOR TWEAKS TO THE FORECAST THIS MORNING. TEMPERATURES WERE
MAINLY ABOVE FREEZING ACROSS SOUTHERN NEW ENGLAND. STILL SOME
ISOLATED LOCATIONS AROUND FREEZING...SO CANNOT COMPLETELY RULE OUT
SOME ICING THIS MORNING. IT WILL BE TOO SHORT-LIVED AND ISOLATED TO
WARRANT A FREEZING RAIN ADVISORY.
PREVIOUS DISCUSSION...
*/ EARLY-HALF OF TUESDAY...
INCREASING DIFFLUENCE ALOFT AHEAD OF A N-STREAM IMPULSE YIELDS DEEP-
LAYER LIFT ALONG THE SURFACE REFLECTION OF WARM- AND COLD-FRONTAL
BOUNDARIES OF AN ASSOCIATED CONTINENTAL AIRMASS. SHOWER ACTIVITY
WITH THE LEADING EDGE OF LOW- TO MID-LEVEL WARM NOSE ACROSS E PA
INTO UPSTATE NY HAS BEGUN TO PUSH INTO S NEW ENGLAND. WILL TAKE A
BIT OF TIME IN REACHING THE GROUND HAVING TO OVERCOME LOW-LEVEL
DRY AIR. EXPECT A SECOND-ACT OF SHOWERS TOWARDS MIDDAY ALONG AND
AHEAD OF A FOLLOW-UP COLD FRONT. STORM-TOTAL PRECIPITATION AMOUNTS
AROUND ONE- TO TWO-TENTHS.
FEEL THE HRRR HAS THE BEST HANDLE ON THE PRESENT SITUATION AND WILL
USE IT AS GUIDANCE TOWARDS POP-TRENDS GOING HIGH-CATEGORICAL. HRRR
TEMPERATURE AND DEWPOINT TRENDS ARE NOT BAD...BUT WILL NOT USE AS
FIRST-ORDER GUIDANCE. WILL BLEND WITH SOME CONSENSUS.
FREEZING RAIN...DEPENDENT ON PRECIPITATION TIMING AND WHETHER THE
COLUMN SATURATES COMPLETELY TO THE SURFACE AS THERE IS STILL A LOT
OF LOW-LEVEL DRY AIR TO OVERCOME PER 0Z CHATHAM SOUNDING. BELIEVE
CHANCES INCREASE TOWARDS MORNING AS LOW-LEVELS WETBULB AS THE COLUMN
SATURATES...THOUGH WITH A LIGHT PRECIPITATION EVENT THINKING NOT AS
SUBSTANTIAL. NEVERTHELESS...A FREEZING RAIN POTENTIAL DOES EXIST
ESPECIALLY WITHIN NESTLED VALLEYS ACROSS N MA WHERE LOWER DEWPOINT
AIR MAY REMAIN TRAPPED. THINK ANY FREEZING RAIN WILL BE BRIEF AND
THAT ANY ICE ACCUMULATION WILL BE NO MORE THAN A TRACE AND HARDLY
NOTICEABLE.
DENSE FOG...LIGHT ONSHORE S/SW-FLOW OF HIGHER DEWPOINT AIR COMBINED
WITH MOISTURE ASSOCIATED WITH SHOWERS PRESENTS POSSIBLE PATCHY DENSE
FOG CONDITIONS...THE GREATER CHANCE OF WHICH WOULD BE OVER A DEEPER
SNOWPACK AND ACROSS COLDER WATERS. INTUITION LEADS ME TO BELIEVE ANY
FOG WILL BE SHALLOW ACROSS THE INTERIOR...WITH HIGHEST CONFIDENCE OF
SOUPY CONDITIONS AROUND THE UPPER-CAPE ADJACENT TO NEAR-SHORE COLDER
WATERS. WORST CONDITIONS AROUND THE MORNING-MIDDAY TIMEFRAME PRIOR
TO COLD FRONTAL PASSAGE.
*/ LATER-HALF OF TUESDAY INTO TUESDAY NIGHT...
ARCTIC AIRMASS BUILDS ACROSS THE REGION IN WAKE OF THE COLD FRONT.
DEEP BOUNDARY-LAYER MIXING UP TO H7 YIELDS THE MIX-DOWN OF FASTER
MOMENTUM AND DRIER AIR. AN UNSTABLE ENVIRONMENT THROUGH WHICH THE
AVAILABILITY OF MOISTURE IS SOMEWHAT IN QUESTION AS TOWARDS THE
DEVELOPMENT OF RAIN / SNOW SQUALLS.
RAIN / SNOW SHOWERS...HIGH-RES GUIDANCE INDICATES THE PRESENCE OF
ACTIVITY ESPECIALLY AS MID-LEVEL ENERGY STRETCHES ACROSS THE
REGION WITHIN THE W-PERIPHERY OF A CLOSED LOW FEATURE SLIDING
OFFSHORE. DECENT SNOW-SQUALL PARAMETER VALUES SUGGESTED BY THE
BURLINGTON WFO WRF WITH THE COMBINATION OF ENHANCED ASCENT OF AN
UNSTABLE PROFILE. IT JUST REMAINS A QUESTION OF MOISTURE
AVAILABILITY...AND AS TO THE INTENSITY OF ACTIVITY OF WHICH WOULD
INFLUENCE EVAPORATIONAL COOLING PROCESSES RESULTING IN RAIN
TRANSITIONING TO SNOW. PREFER TO STICK WITH SLIGHT CHANCE POPS
INDICATING AN ISOLATED THREAT WITH AN EQUAL MIX OF RAIN AND SNOW
CHANCES. HIGHEST CONFIDENCE OF IMPACT WOULD BE ALONG W-SLOPES OF
HIGHER TERRAIN WITH OROGRAPHIC TENDENCIES WHEREAS ON THE LEE-
SIDE...DOWNSLOPING WINDS LIKELY TO LIMIT POTENTIAL.
WIND GUSTS...WILL PREVAIL A HALF-AND-HALF BLEND OF POWER REGRESSION
MIX-DOWN OF WINDS PER BUFKIT PROFILES AND A CONSENSUS BLEND OF WIND
GUST FORECAST GUIDANCE. POWER REGRESSION WAS THE STRONGER OF THE TWO
INDICATING WIND ADVISORY CRITERIA ACROSS E-COASTAL MA. NEVERTHELESS
THE BLEND YIELDED AROUND 30-35 MPH NW-GUSTS FOR INTERIOR NEW ENGLAND
AND AROUND 35-40 MPH FOR E/S-COASTAL MA AND RI...STRONGEST ACROSS
CAPE COD AND NANTUCKET WITH 40-45 MPH WIND GUSTS POSSIBLY EXCEEDING
50 MPH. WILL NOT MAKE ANY CHANGES TO THE HEADLINES. CAN NOT RULE OUT
WIND ADVISORY CRITERIA FOR THE TIP OF CAPE ANN...BUT BEING SO BRIEF
DID NOT GO WITH ANY HEADLINE. COULD ALSO SEE STRONGER WIND GUSTS
ALONG THE LEE-SLOPES OF HIGHER TERRAIN WITH DOWNSLOPING.
&&
.SHORT TERM /WEDNESDAY/...
*/ WEDNESDAY...
DRY COLD AND BLUSTERY. CONTINUED ARCTIC AIRMASS ALOFT YIELDING AN
UNSTABLE BOUNDARY-LAYER PROFILE UP TO H7 ALONG WITH STRETCHED MID-
LEVEL ENERGY THROUGH THE W-PERIPHERY OF A CLOSED LOW DEEPENING OFF
THE COAST OF NOVA SCOTIA.
RAIN/SNOW SHOWERS...ACTIVITY MAY STILL PERSIST THOUGH CONTINUE TO BE
AN ISOLATED THREAT. WILL CONTINUE WITH SLIGHT CHANCE POPS. EXPECT
ACTIVITY TO DIMINISH TOWARDS THE LATER-HALF OF THE DAY AS HIGH
PRESSURE BUILDS IN FROM THE W USHERING IN DRIER AIR WHILE EASING
WINDS.
WIND GUSTS...CONTINUED BLUSTERY WITH AROUND 30-35 MPH NW-GUSTS FOR
INTERIOR NEW ENGLAND WITH AROUND 35-40 MPH FOR E/S-COASTAL MA...WITH
GUSTS UP TO 45 MPH FOR THE OUTER-CAPE TOWARDS MIDDAY BY WHICH POINT
THE WIND ADVISORY SHOULD EXPIRE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGHLIGHTS...
* UNSEASONABLY COLD WEATHER LATE WEDNESDAY AND THURSDAY.
* COASTAL LOW MAY AFFECT SOUTHERN NEW ENGLAND FRI AND SAT...BUT
EXACT DETAILS UNCERTAIN.
* MORE COLD WEATHER EXPECTED EARLY NEXT WEEK.
OVERVIEW AND MODEL PREFERENCES...
DECENT MODEL AGREEMENT THROUGH MID WEEK...DETERIORATES LATE THIS
WEEK INTO THIS WEEKEND. OVERALL...EXPECTING A BROAD MID LEVEL
TROUGH TO PERSIST ACROSS SOUTHERN CANADA INTO THIS WEEKEND.
DIFFERENCES ARRIVE IN HOW VARIOUS HIGH LATITUDE SHORTWAVES GET
HANDLED AS THEY MOVE THROUGH THE LONGWAVE FLOW AND MOVE SOUTH.
THIS WILL IN TURN PROVIDE A LARGE INFLUENCE ON STORM TRACK AND
TIMING FRIDAY INTO SATURDAY.
TREND OF THE 17/00Z GUIDANCE HAS BEEN TO SHIFT THE PRIMARY STORM
TRACK FARTHER SOUTH FROM OUR REGION. THE GFS- AND GEFS MEAN-LED
CAMP TAKE THIS STORM SO FAR SOUTH...IT IS DOUBTFUL WE WOULD SEE
ANY PRECIPITATION AT ALL. MEANWHILE THE INTERNATIONAL MODEL
CAMP...LED BY THE CMC AND ECMWF...KEEP THIS STORM IN PLAY FOR
SOUTHERN NEW ENGLAND. SINCE WE HAVE SEEN THIS STORY PLAY OUT MANY
TIMES THE PAST TWO MONTHS...AM THINKING THERE IS ENOUGH POTENTIAL
TO WARRANT AT LEAST A CHANCE OF PRECIPITATION. PREVIOUS FORECAST
COVERED THIS WELL...AND DID NOT CHANGE IT SIGNIFICANTLY.
FOLLOWED A CONSENSUS APPROACH FOR EACH NEXT WEEK...MEANING BELOW
NORMAL TEMPERATURES RETURN...ALONG WITH DRIER WEATHER.
DETAILS...
WEDNESDAY NIGHT...ROBUST LOW LEVEL PRESSURE GRADIENT WILL REALLY
DRIVE COLDER AIR INTO OUR REGION...WITH GUSTY NORTHWEST WINDS.
LIKELY SEE 25-35 MPH WIND GUSTS. THEREFORE...WIND CHILL VALUES ARE
LIKELY TO REMAIN IN THE SINGLE DIGITS TO LOW TEENS. A FEW FLURRIES
POSSIBLE IN E SLOPES OF THE BERKSHIRES AND LITCHFIELD HILLS.
THURSDAY INTO EARLY FRI...HIGH PRESSURE WILL CREST ACROSS SOUTHERN
NEW ENGLAND THROUGH THIS PERIOD...WITH DRY WEATHER PREVAILING.
MODERATING TEMPS ARE EXPECTED...ALTHOUGH HIGHS ARE LIKELY TO
REMAIN BELOW NORMAL THURSDAY. BY FRIDAY...WITH 850 MB TEMPERATURES
REBOUND TO BETWEEN -8C AND -4C...SO WITH THE MID-MARCH SUN ONCE
AGAIN IN PLAY...WILL LIKELY SEE HIGHS CLOSER TO SEASONAL
NORMALS...MAINLY THE LOWER-MID 40S.
LATE FRIDAY INTO SATURDAY...THIS WILL BE THE PERIOD TO WATCH FOR A
POTENTIAL STORM. THERE REMAINS A LOT OF UNCERTAINTY IN THE DETAILS
WITH THIS STORM. GIVEN THE CURRENT TIMING...WOULD EXPECT
PRIMARILY A RAIN-CHANGING-TO-SNOW SCENARIO. WILL HAVE TO WATCH
THE EVOLUTION OF THIS STORM THE NEXT COUPLE OF DAYS. STILL WAY TO
EARLY TO DISCUSS POTENTIAL SNOW ACCUMULATIONS.
SUNDAY INTO MONDAY...
WHILE ASTRONOMICAL SPRING ARRIVES LATE THIS FRIDAY...THE UPPER
LEVELS DID NOT GET THAT MEMO. THE ENERGY DIVING OUT OF THE HUDSON
BAY AREA WILL PUSH A FAIRLY ROBUST ARCTIC FRONT ACROSS OUR REGION
EARLY SUNDAY MORNING...WITH THE POSSIBILITY OF SOME SHOWERS/SNOWS
AS IT MOVES THROUGH. UNSEASONABLY COLD AIR LOOKS TO MAKE A RETURN
TO THE REGION FOR EARLY NEXT WEEK FOLLOWING THIS FRONT.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
9Z UPDATE...
.SHORT-TERM /THROUGH WEDNESDAY/...
TODAY...MODERATE CONFIDENCE.
MVFR/IFR TOWARDS AFTERNOON. -SHRA AND S-WINDS. IFR/LIFR AROUND
THE OUTER CAPE. IMPROVING TOWARDS EVENING IN WAKE OF A COLD
FRONT. WINDS QUICKLY INCREASING OUT OF THE NW. GUSTS AROUND 30 KTS
ACROSS THE INTERIOR...40 KTS FOR THE COAST. STRONGEST ON THE OUTER
CAPE AROUND 45 KTS. ISOLATED SHRA/SHSN.
TONIGHT...HIGH CONFIDENCE.
VFR. CONTINUED BLUSTERY. PERSISTENT NW-WIND GUSTS AROUND 30 KTS
FOR THE INTERIOR...40 KTS COASTAL. ISOLATED SHRA/SHSN.
WEDNESDAY...HIGH CONFIDENCE.
VFR. WINDS SLOWLY DIMINISHING. ISOLATED SHRA/SHSN CONCLUDE.
KBOS TAF...HIGH CONFIDENCE. WILL HOLD MVFR AT LOWEST. LOW RISK OF
IFR DURING SHRA AND PRIOR TO COLD FRONTAL PASSAGE.
KBDL TAF...HIGH CONFIDENCE. WILL HOLD MVFR AT LOWEST. DO NOT
EXPECT ANY IFR CONDITIONS.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
THURSDAY...HIGH CONFIDENCE. VFR.
FRIDAY INTO SATURDAY ...MODERATE CONFIDENCE.
MVFR/IFR CONDITIONS POSSIBLE IN PERIODS OF RAIN AND SNOW.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM /THROUGH WEDNESDAY/...
EARLY-HALF OF TODAY...HIGH CONFIDENCE.
ARCTIC FRONT APPROACHES THE WATERS AHEAD OF WHICH S/SW-WINDS WILL
BE BREEZY. SEAS REMAIN BELOW 5 FEET THOUGH. MAIN CONCERN WILL BE
DENSE FOG...LIKELY MORESO ALONG THE SHORES OF THE UPPER CAPE.
TOWARDS EVENING AND OVERNIGHT...HIGH CONFIDENCE.
IN WAKE OF THE ARCTIC FRONT...NW-WINDS INCREASING IN EXCESS OF
GALE FORCE WITH GUSTS OF AROUND 40-45 KTS. VISIBILITY QUICKLY
IMPROVES BUT SEAS BUILD 10-12 FEET ON THE OUTER WATERS. FREEZING
SPRAY LIKELY WITH POSSIBLE MODERATE AROUND THE SHORES OF THE
UPPER-CAPE. GALE WARNINGS IN PLACE. WILL HOLD OFF ON ANY FREEZING
SPRAY HEADLINES AND ALLOW THE DAY SHIFT TO RE-EVALUATE.
WEDNESDAY...HIGH CONFIDENCE.
BLUSTERY WITH NW-GUSTS AROUND 35-40 KTS SLOWLY DIMINISHING. THERE
STILL WILL REMAIN A FREEZING SPRAY THREAT. SEAS STILL ROUGH AROUND
8 TO 10 FEET ON THE OUTER WATERS. GALE WARNINGS WILL CONTINUE
THROUGH THE PERIOD.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
WEDNESDAY NIGHT THROUGH THURSDAY...HIGH CONFIDENCE.
STRONG NW WINDS WITH GALE FORCE GUSTS EXPECTED. GALE WARNINGS ARE
LIKELY TO BE NEEDED. OTHERWISE...ROUGH SEAS BUILDING 7-10 FT.
WINDS DIMINISH LATE WED NIGHT INTO THU...BUT SMALL CRAFT ADVISORY
LEVEL GUSTS ARE EXPECTED. FREEZING SPRAY POSSIBLE.
FRIDAY AND SATURDAY...MODERATE CONFIDENCE.
LOW PRESSURE MAY PASS NEAR 40N/70W LATE SOMETIME DURING THIS
PERIOD. THIS MAY LEAD TO A PERIOD OF BUILDING SWELLS FIRST ON THE
SOUTHERN OCEAN WATERS...THEN SNEAKING INTO THE EASTERN WATERS AS
WELL. WAVE HEIGHTS UP TO 7-8 FT POSSIBLE. DEPENDING ON THE LOW
PRESSURE TRACK...GALE OR AT THE VERY LEAST SMALL CRAFT ADVISORY
WIND GUSTS ARE POSSIBLE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WIND ADVISORY FROM 6 PM THIS EVENING TO 2 PM EDT WEDNESDAY FOR
MAZ022-024.
RI...NONE.
MARINE...GALE WARNING FROM 5 PM THIS AFTERNOON TO 6 PM EDT WEDNESDAY
FOR ANZ230>235-237-250-251-254>256.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM EDT WEDNESDAY
FOR ANZ236.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
AREA FORECAST DISCUSSION
NWS NEW YORK NY
654 AM EDT TUE MAR 17 2015
.SYNOPSIS...
LOW PRESSURE WILL PASS THROUGH NORTHERN NEW ENGLAND THIS
MORNING...DRAGGING A STRONG COLD FRONT ACROSS THE AREA. HIGH
PRESSURE BUILDS IN FROM THE UPPER MIDWEST TUESDAY NIGHT THROUGH
THURSDAY. A COASTAL LOW PRESSURE SYSTEM MAY IMPACT THE AREA
FRIDAY INTO FRIDAY NIGHT...FOLLOWED BY A COLD FRONT PASSAGE LATE
SATURDAY. HIGH PRESSURE BUILDS TOWARDS THE REGION FROM THE GREAT
LAKES SUNDAY INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST RADAR TRENDS AS WELL AS HRRR AND RAP TRENDS INDICATE LIGHT
RAIN WILL CONTINUE TO DEVELOP AND OVERSPREAD MUCH OF THE REGION
EARLY THIS MORNING. HAVE INCREASED POPS WITH THIS UPDATE TO INCLUDE
LIKELY POPS FOR ALL EXCEPT THE FAR SW CORNER OF THE CWA THROUGH ABOUT
14Z. HIGHEST POPS SHIFT TO SE CT AND EASTERN LONG ISLAND LATE THIS
MORNING WITH RAIN ENDING BY EARLY AFTERNOON.
THE LIGHT RAIN IS IN RESPONSE TO A SHORTWAVE TRACKING ACROSS THE SRN
PORTION OF THE SE CANADIAN PROVINCES EARLY THIS MORNING. SFC LOW
PRES IS DEVELOPING IN RESPONSE TO THIS AND WILL TRACK ACROSS NRN
NEW ENGLAND THIS MORNING...DRAGGING A STRONG COLD FRONT THROUGH
THE AREA.
NW WINDS WILL INCREASE BEHIND COLD FRONT DUE TO THE COMBINATION OF
STRONG CAA AND A TIGHTENING PRES GRADIENT BETWEEN RAPID
INTENSIFICATION OF THE OFFSHORE LOW TO THE NE AND STRONG CANADIAN
HIGH PRES BUILDING TO THE W. WINDS ARE EXPECTED TO RANGE FROM 15
TO 25 MPH WITH GUSTS 40 TO 45 MPH. WE ARE CLOSE TO WIND ADVSY BUT
FALL JUST SHORT...ALTHOUGH SOME OF THE MORE EXPOSED AREAS COULD
REACH IT.
HIGHS ARE CHALLENGING TODAY. THINK THE MAVS ARE WAY TOO HIGH WITH
THE CLOUD COVER...PCPN AND COLD FRONT COMING THROUGH BETWEEN 15Z
AND 18Z. SO CHOSE TO BLEND THE COOLER GUIDANCE. HIGHS WILL DEPEND
ON HOW QUICKLY COLDER AIR STARTS FILTERING IN...WHICH MODELS ARE
IN GOOD AGREEMENT ABOUT BEING AROUND 18Z.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TIGHT PRES GRADIENT REMAINS ACROSS THE REGION INTO WED BEFORE
FINALLY STARTING TO RELAX DURING WED AFTN. GUSTY NW WINDS WILL
CONTINUE DURING THIS TIME...ALTHOUGH THE STRONGEST WINDS WILL HAVE
PASSED.
DEEP NW FLOW WILL SEND WEAK SHORTWAVES THROUGH THE FLOW AS WELL.
MODELS ARE HINTING AT SCT SHOWER ACTIVITY TO THE N AND W OF THE
AREA...BUT NOT CONVINCED IT WILL MAKE IT OVER THE MOUNTAINS DUE TO
DOWNSLOPING. THEREFORE HAVE INCREASED CLOUDS...BUT HAVE KEPT THE
FORECAST DRY.
LOWS TONIGHT WILL BE WELL BELOW NORMAL...RANGING FROM UPPER TEENS
TO AROUND 20 INLAND...LOWER TO MID 20S AT THE COAST...EXCEPT MID
TO UPPER 20S IN THE NYC METRO. THIS IS ABOUT 10 DEGREES BELOW
NORMAL. HIGHS WED WILL CONTINUE TO BE BELOW NORMAL RANGING FROM
MID 30S TO LOWER 40S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
CANADIAN HIGH PRESSURE BUILDS OVERHEAD ON THURSDAY WITH WEAK UPPER
LEVEL RIDGING. COLD AND DRY WEATHER CONTINUES WITH TEMPERATURES NEAR
TEN DEGREES BELOW NORMAL FOR THIS TIME OF YEAR.
ATTENTION THEN TURNS TO ENERGY WITHIN THE NORTHERN BRANCH OF THE
UPPER JET DIGGING INTO THE NORTHERN STATES. THIS ENERGY WILL
FAST APPROACH ON FRIDAY SPAWNING A LOW PRESSURE OFF THE MIDDLE
ATLANTIC COAST. THERE STILL IS A FAIRLY LARGE SPREAD AMONG THE
MEDIUM RANGE OPERATIONAL MODELS AND ENSEMBLES ON THE TIMING AND
AMPLITUDE OF THIS ENERGY. THIS LEADS TO TRACK AND STRENGTH
DIFFERENCES WITH THE DEVELOPING LOW PRESSURE. THE GFS AND ITS
ENSEMBLES CONTINUE TO BE FURTHEST SOUTH WITH THE LOW KEEPING THE
HEAVIEST PRECIPITATION SOUTH OF LONG ISLAND. THE EURO AND CMC ARE
FURTHER NORTH WITH THE LOW BRINGING MORE SUBSTANTIAL PRECIPITATION
FRIDAY INTO AT LEAST THE FIRST PART OF FRIDAY NIGHT. WITH THERE
STILL REMAINING A FAIRLY LARGE SPREAD BEING DEPICTED BY THE 00Z
MODELS...HAVE OPTED TO STAY WITH HIGH CHANCE POPS FOR THIS FORECAST
PACKAGE.
COMPLICATED PTYPE FORECAST AS THE COLD AIR SOURCE FROM THE SURFACE
HIGH PRESSURE SHIFTS OFFSHORE DURING THE DAY FRIDAY ALLOWING SURFACE
WINDS TO BECOME EAST OR EVEN SOUTHEAST WARMING THE BOUNDARY LAYER.
SOME MID LEVEL WARMTH IS ALSO POSSIBLE FURTHER COMPLICATING THE
PTYPE...HAVE MAINTAINED CONSISTENT WORDING FROM PREVIOUS FORECAST OF
RAIN AND SNOW DUE TO CONTINUED UNCERTAINTY IN THERMAL PROFILES.
THE LOW QUICKLY MOVES OFFSHORE LATE FRIDAY NIGHT FOLLOWED BY THE
APPROACH OF ANOTHER COLD FRONT ON SATURDAY. TEMPERATURES MAY
APPROACH NORMAL LEVELS BRIEFLY ON SATURDAY AHEAD OF THE FRONT.
CURRENTLY FORECASTING SLIGHT CHANCE POPS WITH THE FRONT PASSAGE
SATURDAY NIGHT. CANADIAN HIGH PRESSURE THEN BUILDS INTO THE REGION
SUNDAY INTO MONDAY WITH TEMPERATURES FALLING BACK BELOW NORMAL.
TEMPERATURES SHOULD AVERAGE AROUND TEN DEGREES BELOW NORMAL SUNDAY
INTO MONDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
LOW PRES PASSING NORTH OF THE AREA WILL DRAG A WARM FRONT THROUGH
THE REGION EARLY THIS MORNING...AND THEN A COLD FRONT ACROSS THE
REGION THIS AFTERNOON.
RAIN THIS MORNING WITH MVFR AND LOCAL IFR CONDS...MAINLY ACROSS
NORTHERN TERMINALS.
RAIN ENDS FROM 14-16Z WITH PASSAGE OF COLD FRONT AND CONDS IMPROVE
TO VFR.
WINDS VEER TO THE NW AND INCREASE TO 15-20 KT WITH 20-30 KT GUSTS
BY MIDDAY...AND THEN TO 20-25 KT WITH 30-35 KT GUSTS BY LATE
AFTERNOON. WINDS GRADUALLY DIMINISH TONIGHT.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM THE LEFT OF 310 MAG TO THE RIGHT. WINDS
INCREASE TO AROUND 15 KT WITH GUSTS UP TO 25 KT BY 18Z...AND THEN
FURTHER INCREASE TO 20-25 KT WITH 30-35 KT GUSTS BY 21Z.
KLGA FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM THE LEFT OF 310 MAG TO THE RIGHT. WINDS
INCREASE TO AROUND 15 KT WITH GUSTS UP TO 25 KT BY 18Z...AND THEN
FURTHER INCREASE TO 20-25 KT WITH 30-35 KT GUSTS BY 21Z.
KEWR FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM THE LEFT OF 310 MAG TO THE RIGHT. WINDS
INCREASE TO AROUND 15 KT WITH GUSTS UP TO 25 KT BY 18Z...AND THEN
FURTHER INCREASE TO 20-25 KT WITH 30-35 KT GUSTS BY 21Z.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM SW TO NW. WINDS INCREASE TO AROUND 15 KT
WITH GUSTS UP TO 25 KT BY 18Z...AND THEN FURTHER INCREASE TO AROUND
20 KT WITH GUSTS UP TO 30 KT.
KHPN FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM SW TO NW. WINDS INCREASE TO AROUND 15 KT
WITH GUSTS UP TO 25 KT BY 18Z...AND THEN FURTHER INCREASE TO AROUND
20 KT WITH GUSTS UP TO 30 KT.
KISP FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM SW TO NW. WINDS INCREASE TO AROUND 15 KT
WITH GUSTS UP TO 25 KT BY 18Z...AND THEN FURTHER INCREASE TO AROUND
20 KT WITH GUSTS UP TO 30 KT.
OUTLOOK FOR 09Z WEDNESDAY THROUGH SATURDAY...
.TONIGHT...VFR. DIMINISHING WINDS.
.WEDNESDAY...VFR. NW WINDS 15-20 KT WITH GUSTS UP TO 30 KT.
.WEDNESDAY NIGHT...VFR. DIMINISHING WINDS.
.THURSDAY...VFR. NW WINDS 10-15 KT.
.FRIDAY...IFR POSSIBLE IN SN AND RA.
.SATURDAY...VFR.
&&
.MARINE...
BASED ON THE LATEST SOUNDINGS WHICH ARE IN GOOD AGREEMENT...HAVE
UPGRADED ALL OF THE NON-OCEAN WATERS TO A GALE WARNING. WHILE
MIXING MAY NOT BE AS HIGH AS INDICATED DUE TO THE COLD
WATERS...THE LEVEL OF 35 KT WINDS IS FAIRLY LOW IN THE SOUNDINGS.
THE WARNING BEGINS AT 18Z ALTHOUGH IT COULD BE A FEW HOURS LATER
DEPENDING ON HOW QUICKLY THE COLDER AIR STARTS FILTERING IN. HAVE
THE WARNING ENDING AT 10Z TONIGHT...ALTHOUGH IT MAY NEED TO BE
CONTINUED ON THE OCEAN WATERS INTO WED. IT IS MARGINAL WED MORNING
SO DIDN`T HAVE THE CONFIDENCE TO GO ANY FURTHER. SCA WILL LIKELY
BE NEEDED OTHERWISE WITH A GUSTY NW FLOW CONTINUING.
WINDS AND SEAS FALL BELOW SCA LEVELS WEDNESDAY NIGHT AS HIGH
PRESSURE BUILDS OVER THE WATERS. THESE CONDITIONS ARE EXPECTED TO
CONTINUE THROUGH FRIDAY MORNING LOW PRESSURE THEN DEVELOPS OFF THE
MIDDLE ATLANTIC COAST FRIDAY INTO FRIDAY NIGHT. WINDS SHOULD
CONTINUE TO STAY JUST BELOW SCA LEVELS...BUT SEAS MAY BUILD SCA
LEVELS ON THE OCEAN FRIDAY NIGHT INTO SATURDAY.
&&
.HYDROLOGY...
LESS THAN 1/4 INCH OF RAIN IS EXPECTED THIS MORNING. HIGHEST AMOUNTS
WILL BE CONFINED TO THE SRN CT...AND THE TWIN FORKS OF LI.
THE POTENTIAL EXISTS FOR 1/2 TO 1 INCH OF LIQUID EQUIVALENT ON
FRIDAY INTO FRIDAY NIGHT. SOME OF THIS MAY FALL IN THE FROZEN
STATE BEFORE CHANGING OVER TO LIQUID.
RECENT INCREASED FLOW ON RIVERS/STREAMS...PARTICULARLY ACROSS THE
LOWER HUDSON VALLEY AND SOUTHERN CT...COUPLED WITH MILD
TEMPERATURES...MAY CAUSE ICE BREAKUP/MOVEMENT INTO EARLY THIS
WEEK. THIS SHOULD MAKE ICE JAMS AND LOCALIZED FLOODING POSSIBLE.
ICE JAM FLOODING IS UNPREDICTABLE AND SUDDEN...SO INTERESTS ALONG
ICE COVERED RIVERS SHOULD MONITOR NWS FORECASTS FOR THE LATEST
INFORMATION.
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 WEB SITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...GALE WARNING FROM 2 PM THIS AFTERNOON TO 6 AM EDT WEDNESDAY
FOR ANZ330-335-338-340-345-350-353-355.
&&
$$
SYNOPSIS...24/DS
NEAR TERM...24/DS
SHORT TERM...24
LONG TERM...DS
AVIATION...MPS
MARINE...24/DS
HYDROLOGY...24/DS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
513 AM EDT TUE MAR 17 2015
.SYNOPSIS...
SHOWERS ANTICIPATED AHEAD OF AN ARCTIC FRONT...WHICH WILL SWEEP
ACROSS SOUTHERN NEW ENGLAND THIS AFTERNOON. BLUSTERY AND
UNSEASONABLY COLD WEATHER WILL FOLLOW INTO THURSDAY. A WINTER
STORM MAY IMPACT OUR REGION LATE FRIDAY INTO SATURDAY.
OTHERWISE...DRY AND UNSEASONABLY COLD WEATHER EXPECTED FOR EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
*/ EARLY-HALF OF TUESDAY...
INCREASING DIFFLUENCE ALOFT AHEAD OF A N-STREAM IMPULSE YIELDS DEEP-
LAYER LIFT ALONG THE SURFACE REFLECTION OF WARM- AND COLD-FRONTAL
BOUNDARIES OF AN ASSOCIATED CONTINENTAL AIRMASS. SHOWER ACTIVITY
WITH THE LEADING EDGE OF LOW- TO MID-LEVEL WARM NOSE ACROSS E PA
INTO UPSTATE NY HAS BEGUN TO PUSH INTO S NEW ENGLAND. WILL TAKE A
BIT OF TIME IN REACHING THE GROUND HAVING TO OVERCOME LOW-LEVEL
DRY AIR. EXPECT A SECOND-ACT OF SHOWERS TOWARDS MIDDAY ALONG AND
AHEAD OF A FOLLOW-UP COLD FRONT. STORM-TOTAL PRECIPITATION AMOUNTS
AROUND ONE- TO TWO-TENTHS.
FEEL THE HRRR HAS THE BEST HANDLE ON THE PRESENT SITUATION AND WILL
USE IT AS GUIDANCE TOWARDS POP-TRENDS GOING HIGH-CATEGORICAL. HRRR
TEMPERATURE AND DEWPOINT TRENDS ARE NOT BAD...BUT WILL NOT USE AS
FIRST-ORDER GUIDANCE. WILL BLEND WITH SOME CONSENSUS.
FREEZING RAIN...DEPENDENT ON PRECIPITATION TIMING AND WHETHER THE
COLUMN SATURATES COMPLETELY TO THE SURFACE AS THERE IS STILL A LOT
OF LOW-LEVEL DRY AIR TO OVERCOME PER 0Z CHATHAM SOUNDING. BELIEVE
CHANCES INCREASE TOWARDS MORNING AS LOW-LEVELS WETBULB AS THE COLUMN
SATURATES...THOUGH WITH A LIGHT PRECIPITATION EVENT THINKING NOT AS
SUBSTANTIAL. NEVERTHELESS...A FREEZING RAIN POTENTIAL DOES EXIST
ESPECIALLY WITHIN NESTLED VALLEYS ACROSS N MA WHERE LOWER DEWPOINT
AIR MAY REMAIN TRAPPED. THINK ANY FREEZING RAIN WILL BE BRIEF AND
THAT ANY ICE ACCUMULATION WILL BE NO MORE THAN A TRACE AND HARDLY
NOTICEABLE.
DENSE FOG...LIGHT ONSHORE S/SW-FLOW OF HIGHER DEWPOINT AIR COMBINED
WITH MOISTURE ASSOCIATED WITH SHOWERS PRESENTS POSSIBLE PATCHY DENSE
FOG CONDITIONS...THE GREATER CHANCE OF WHICH WOULD BE OVER A DEEPER
SNOWPACK AND ACROSS COLDER WATERS. INTUITION LEADS ME TO BELIEVE ANY
FOG WILL BE SHALLOW ACROSS THE INTERIOR...WITH HIGHEST CONFIDENCE OF
SOUPY CONDITIONS AROUND THE UPPER-CAPE ADJACENT TO NEAR-SHORE COLDER
WATERS. WORST CONDITIONS AROUND THE MORNING-MIDDAY TIMEFRAME PRIOR
TO COLD FRONTAL PASSAGE.
*/ LATER-HALF OF TUESDAY INTO TUESDAY NIGHT...
ARCTIC AIRMASS BUILDS ACROSS THE REGION IN WAKE OF THE COLD FRONT.
DEEP BOUNDARY-LAYER MIXING UP TO H7 YIELDS THE MIX-DOWN OF FASTER
MOMENTUM AND DRIER AIR. AN UNSTABLE ENVIRONMENT THROUGH WHICH THE
AVAILABILITY OF MOISTURE IS SOMEWHAT IN QUESTION AS TOWARDS THE
DEVELOPMENT OF RAIN / SNOW SQUALLS.
RAIN / SNOW SHOWERS...HIGH-RES GUIDANCE INDICATES THE PRESENCE OF
ACTIVITY ESPECIALLY AS MID-LEVEL ENERGY STRETCHES ACROSS THE
REGION WITHIN THE W-PERIPHERY OF A CLOSED LOW FEATURE SLIDING
OFFSHORE. DECENT SNOW-SQUALL PARAMETER VALUES SUGGESTED BY THE
BURLINGTON WFO WRF WITH THE COMBINATION OF ENHANCED ASCENT OF AN
UNSTABLE PROFILE. IT JUST REMAINS A QUESTION OF MOISTURE
AVAILABILITY...AND AS TO THE INTENSITY OF ACTIVITY OF WHICH WOULD
INFLUENCE EVAPORATIONAL COOLING PROCESSES RESULTING IN RAIN
TRANSITIONING TO SNOW. PREFER TO STICK WITH SLIGHT CHANCE POPS
INDICATING AN ISOLATED THREAT WITH AN EQUAL MIX OF RAIN AND SNOW
CHANCES. HIGHEST CONFIDENCE OF IMPACT WOULD BE ALONG W-SLOPES OF
HIGHER TERRAIN WITH OROGRAPHIC TENDENCIES WHEREAS ON THE LEE-
SIDE...DOWNSLOPING WINDS LIKELY TO LIMIT POTENTIAL.
WIND GUSTS...WILL PREVAIL A HALF-AND-HALF BLEND OF POWER REGRESSION
MIX-DOWN OF WINDS PER BUFKIT PROFILES AND A CONSENSUS BLEND OF WIND
GUST FORECAST GUIDANCE. POWER REGRESSION WAS THE STRONGER OF THE TWO
INDICATING WIND ADVISORY CRITERIA ACROSS E-COASTAL MA. NEVERTHELESS
THE BLEND YIELDED AROUND 30-35 MPH NW-GUSTS FOR INTERIOR NEW ENGLAND
AND AROUND 35-40 MPH FOR E/S-COASTAL MA AND RI...STRONGEST ACROSS
CAPE COD AND NANTUCKET WITH 40-45 MPH WIND GUSTS POSSIBLY EXCEEDING
50 MPH. WILL NOT MAKE ANY CHANGES TO THE HEADLINES. CAN NOT RULE OUT
WIND ADVISORY CRITERIA FOR THE TIP OF CAPE ANN...BUT BEING SO BRIEF
DID NOT GO WITH ANY HEADLINE. COULD ALSO SEE STRONGER WIND GUSTS
ALONG THE LEE-SLOPES OF HIGHER TERRAIN WITH DOWNSLOPING.
&&
.SHORT TERM /WEDNESDAY/...
*/ WEDNESDAY...
DRY COLD AND BLUSTERY. CONTINUED ARCTIC AIRMASS ALOFT YIELDING AN
UNSTABLE BOUNDARY-LAYER PROFILE UP TO H7 ALONG WITH STRETCHED MID-
LEVEL ENERGY THROUGH THE W-PERIPHERY OF A CLOSED LOW DEEPENING OFF
THE COAST OF NOVA SCOTIA.
RAIN/SNOW SHOWERS...ACTIVITY MAY STILL PERSIST THOUGH CONTINUE TO BE
AN ISOLATED THREAT. WILL CONTINUE WITH SLIGHT CHANCE POPS. EXPECT
ACTIVITY TO DIMINISH TOWARDS THE LATER-HALF OF THE DAY AS HIGH
PRESSURE BUILDS IN FROM THE W USHERING IN DRIER AIR WHILE EASING
WINDS.
WIND GUSTS...CONTINUED BLUSTERY WITH AROUND 30-35 MPH NW-GUSTS FOR
INTERIOR NEW ENGLAND WITH AROUND 35-40 MPH FOR E/S-COASTAL MA...WITH
GUSTS UP TO 45 MPH FOR THE OUTER-CAPE TOWARDS MIDDAY BY WHICH POINT
THE WIND ADVISORY SHOULD EXPIRE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGHLIGHTS...
* UNSEASONABLY COLD WEATHER LATE WEDNESDAY AND THURSDAY.
* COASTAL LOW MAY AFFECT SOUTHERN NEW ENGLAND FRI AND SAT...BUT
EXACT DETAILS UNCERTAIN.
* MORE COLD WEATHER EXPECTED EARLY NEXT WEEK.
OVERVIEW AND MODEL PREFERENCES...
DECENT MODEL AGREEMENT THROUGH MID WEEK...DETERIORATES LATE THIS
WEEK INTO THIS WEEKEND. OVERALL...EXPECTING A BROAD MID LEVEL
TROUGH TO PERSIST ACROSS SOUTHERN CANADA INTO THIS WEEKEND.
DIFFERENCES ARRIVE IN HOW VARIOUS HIGH LATITUDE SHORTWAVES GET
HANDLED AS THEY MOVE THROUGH THE LONGWAVE FLOW AND MOVE SOUTH.
THIS WILL IN TURN PROVIDE A LARGE INFLUENCE ON STORM TRACK AND
TIMING FRIDAY INTO SATURDAY.
TREND OF THE 17/00Z GUIDANCE HAS BEEN TO SHIFT THE PRIMARY STORM
TRACK FARTHER SOUTH FROM OUR REGION. THE GFS- AND GEFS MEAN-LED
CAMP TAKE THIS STORM SO FAR SOUTH...IT IS DOUBTFUL WE WOULD SEE
ANY PRECIPITATION AT ALL. MEANWHILE THE INTERNATIONAL MODEL
CAMP...LED BY THE CMC AND ECMWF...KEEP THIS STORM IN PLAY FOR
SOUTHERN NEW ENGLAND. SINCE WE HAVE SEEN THIS STORY PLAY OUT MANY
TIMES THE PAST TWO MONTHS...AM THINKING THERE IS ENOUGH POTENTIAL
TO WARRANT AT LEAST A CHANCE OF PRECIPITATION. PREVIOUS FORECAST
COVERED THIS WELL...AND DID NOT CHANGE IT SIGNIFICANTLY.
FOLLOWED A CONSENSUS APPROACH FOR EACH NEXT WEEK...MEANING BELOW
NORMAL TEMPERATURES RETURN...ALONG WITH DRIER WEATHER.
DETAILS...
WEDNESDAY NIGHT...ROBUST LOW LEVEL PRESSURE GRADIENT WILL REALLY
DRIVE COLDER AIR INTO OUR REGION...WITH GUSTY NORTHWEST WINDS.
LIKELY SEE 25-35 MPH WIND GUSTS. THEREFORE...WIND CHILL VALUES ARE
LIKELY TO REMAIN IN THE SINGLE DIGITS TO LOW TEENS. A FEW FLURRIES
POSSIBLE IN E SLOPES OF THE BERKSHIRES AND LITCHFIELD HILLS.
THURSDAY INTO EARLY FRI...HIGH PRESSURE WILL CREST ACROSS SOUTHERN
NEW ENGLAND THROUGH THIS PERIOD...WITH DRY WEATHER PREVAILING.
MODERATING TEMPS ARE EXPECTED...ALTHOUGH HIGHS ARE LIKELY TO
REMAIN BELOW NORMAL THURSDAY. BY FRIDAY...WITH 850 MB TEMPERATURES
REBOUND TO BETWEEN -8C AND -4C...SO WITH THE MID-MARCH SUN ONCE
AGAIN IN PLAY...WILL LIKELY SEE HIGHS CLOSER TO SEASONAL
NORMALS...MAINLY THE LOWER-MID 40S.
LATE FRIDAY INTO SATURDAY...THIS WILL BE THE PERIOD TO WATCH FOR A
POTENTIAL STORM. THERE REMAINS A LOT OF UNCERTAINTY IN THE DETAILS
WITH THIS STORM. GIVEN THE CURRENT TIMING...WOULD EXPECT
PRIMARILY A RAIN-CHANGING-TO-SNOW SCENARIO. WILL HAVE TO WATCH
THE EVOLUTION OF THIS STORM THE NEXT COUPLE OF DAYS. STILL WAY TO
EARLY TO DISCUSS POTENTIAL SNOW ACCUMULATIONS.
SUNDAY INTO MONDAY...
WHILE ASTRONOMICAL SPRING ARRIVES LATE THIS FRIDAY...THE UPPER
LEVELS DID NOT GET THAT MEMO. THE ENERGY DIVING OUT OF THE HUDSON
BAY AREA WILL PUSH A FAIRLY ROBUST ARCTIC FRONT ACROSS OUR REGION
EARLY SUNDAY MORNING...WITH THE POSSIBILITY OF SOME SHOWERS/SNOWS
AS IT MOVES THROUGH. UNSEASONABLY COLD AIR LOOKS TO MAKE A RETURN
TO THE REGION FOR EARLY NEXT WEEK FOLLOWING THIS FRONT.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
9Z UPDATE...
.SHORT-TERM /THROUGH WEDNESDAY/...
TODAY...MODERATE CONFIDENCE.
MVFR/IFR TOWARDS AFTERNOON. -SHRA AND S-WINDS. IFR/LIFR AROUND
THE OUTER-CAPE. IMPROVING TOWARDS EVENING IN WAKE OF A COLD FRONT.
WINDS QUICKLY INCREASING OUT OF THE NW. GUSTS AROUND 30 KTS ACROSS
THE INTERIOR...40 KTS FOR THE COAST. STRONGEST ON THE OUTER CAPE
AROUND 45 KTS. ISOLATED SHRA/SHSN.
TONIGHT...HIGH CONFIDENCE.
VFR. CONTINUED BLUSTERY. PERSISTENT NW-WIND GUSTS AROUND 30 KTS
FOR THE INTERIOR...40 KTS COASTAL. ISOLATED SHRA/SHSN.
WEDNESDAY...HIGH CONFIDENCE.
VFR. WINDS SLOWLY DIMINISHING. ISOLATED SHRA/SHSN CONCLUDE.
KBOS TAF...HIGH CONFIDENCE. WILL HOLD MVFR AT LOWEST. LOW RISK OF
IFR DURING SHRA AND PRIOR TO COLD FRONTAL PASSAGE.
KBDL TAF...HIGH CONFIDENCE. WILL HOLD MVFR AT LOWEST. DO NOT
EXPECT ANY IFR CONDITIONS.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
THURSDAY...HIGH CONFIDENCE. VFR.
FRIDAY INTO SATURDAY ...MODERATE CONFIDENCE.
MVFR/IFR CONDITIONS POSSIBLE IN PERIODS OF RAIN AND SNOW.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM /THROUGH WEDNESDAY/...
EARLY-HALF OF TODAY...HIGH CONFIDENCE.
ARCTIC FRONT APPROACHES THE WATERS AHEAD OF WHICH S/SW-WINDS WILL
BE BREEZY. SEAS REMAIN BELOW 5-FEET THOUGH. MAIN CONCERN WILL BE
DENSE FOG...LIKELY MORESO ALONG THE SHORES OF THE UPPER-CAPE.
TOWARDS EVENING AND OVERNIGHT...HIGH CONFIDENCE.
IN WAKE OF THE ARCTIC FRONT...NW-WINDS INCREASING IN EXCESS OF
GALE FORCE WITH GUSTS OF AROUND 40-45 KTS. VISIBILITY QUICKLY
IMPROVES BUT SEAS BUILD 10-12 FEET ON THE OUTER WATERS. FREEZING
SPRAY LIKELY WITH POSSIBLE MODERATE AROUND THE SHORES OF THE
UPPER-CAPE. GALE WARNINGS IN PLACE. WILL HOLD OFF ON ANY FREEZING
SPRAY HEADLINES AND ALLOW THE DAY-SHIFT TO RE-EVALUATE.
WEDNESDAY...HIGH CONFIDENCE.
BLUSTERY WITH NW-GUSTS AROUND 35-40 KTS SLOWLY DIMINISHING. THERE
STILL WILL REMAIN A FREEZING SPRAY THREAT. SEAS STILL ROUGH AROUND
8 TO 10 FEET ON THE OUTER WATERS. GALE WARNINGS WILL CONTINUE
THROUGH THE PERIOD.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
WEDNESDAY NIGHT THROUGH THURSDAY...HIGH CONFIDENCE.
STRONG NW WINDS WITH GALE FORCE GUSTS EXPECTED. GALE WARNINGS ARE
LIKELY TO BE NEEDED. OTHERWISE...ROUGH SEAS BUILDING 7-10 FT.
WINDS DIMINISH LATE WED NIGHT INTO THU...BUT SMALL CRAFT ADVISORY
LEVEL GUSTS ARE EXPECTED. FREEZING SPRAY POSSIBLE.
FRIDAY AND SATURDAY...MODERATE CONFIDENCE.
LOW PRESSURE MAY PASS NEAR 40N/70W LATE SOMETIME DURING THIS
PERIOD. THIS MAY LEAD TO A PERIOD OF BUILDING SWELLS FIRST ON THE
SOUTHERN OCEAN WATERS...THEN SNEAKING INTO THE EASTERN WATERS AS
WELL. WAVE HEIGHTS UP TO 7-8 FT POSSIBLE. DEPENDING ON THE LOW
PRESSURE TRACK...GALE OR AT THE VERY LEAST SMALL CRAFT ADVISORY
WIND GUSTS ARE POSSIBLE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WIND ADVISORY FROM 6 PM THIS EVENING TO 2 PM EDT WEDNESDAY FOR
MAZ022-024.
RI...NONE.
MARINE...GALE WARNING FROM 5 PM THIS AFTERNOON TO 6 PM EDT WEDNESDAY
FOR ANZ230>235-237-250-251-254>256.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM EDT WEDNESDAY
FOR ANZ236.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
AREA FORECAST DISCUSSION
NWS TAUNTON MA
448 AM EDT TUE MAR 17 2015
.SYNOPSIS...
SHOWERS ANTICIPATED AHEAD OF AN ARCTIC FRONT...WHICH WILL SWEEP
ACROSS SOUTHERN NEW ENGLAND THIS AFTERNOON. BLUSTERY AND
UNSEASONABLY COLD WEATHER WILL FOLLOW INTO THURSDAY. A WINTER
STORM MAY IMPACT OUR REGION LATE FRIDAY INTO SATURDAY.
OTHERWISE...DRY AND UNSEASONABLY COLD WEATHER EXPECTED FOR EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
*/ EARLY-HALF OF TUESDAY...
INCREASING DIFFLUENCE ALOFT AHEAD OF A N-STREAM IMPULSE YIELDS DEEP-
LAYER LIFT ALONG THE SURFACE REFLECTION OF WARM- AND COLD-FRONTAL
BOUNDARIES OF AN ASSOCIATED CONTINENTAL AIRMASS. SHOWER ACTIVITY
WITH THE LEADING EDGE OF LOW- TO MID-LEVEL WARM NOSE ACROSS E PA
INTO UPSTATE NY HAS BEGUN TO PUSH INTO S NEW ENGLAND. WILL TAKE A
BIT OF TIME IN REACHING THE GROUND HAVING TO OVERCOME LOW-LEVEL
DRY AIR. EXPECT A SECOND-ACT OF SHOWERS TOWARDS MIDDAY ALONG AND
AHEAD OF A FOLLOW-UP COLD FRONT. STORM-TOTAL PRECIPITATION AMOUNTS
AROUND ONE- TO TWO-TENTHS.
FEEL THE HRRR HAS THE BEST HANDLE ON THE PRESENT SITUATION AND WILL
USE IT AS GUIDANCE TOWARDS POP-TRENDS GOING HIGH-CATEGORICAL. HRRR
TEMPERATURE AND DEWPOINT TRENDS ARE NOT BAD...BUT WILL NOT USE AS
FIRST-ORDER GUIDANCE. WILL BLEND WITH SOME CONSENSUS.
FREEZING RAIN...DEPENDENT ON PRECIPITATION TIMING AND WHETHER THE
COLUMN SATURATES COMPLETELY TO THE SURFACE AS THERE IS STILL A LOT
OF LOW-LEVEL DRY AIR TO OVERCOME PER 0Z CHATHAM SOUNDING. BELIEVE
CHANCES INCREASE TOWARDS MORNING AS LOW-LEVELS WETBULB AS THE COLUMN
SATURATES...THOUGH WITH A LIGHT PRECIPITATION EVENT THINKING NOT AS
SUBSTANTIAL. NEVERTHELESS...A FREEZING RAIN POTENTIAL DOES EXIST
ESPECIALLY WITHIN NESTLED VALLEYS ACROSS N MA WHERE LOWER DEWPOINT
AIR MAY REMAIN TRAPPED. THINK ANY FREEZING RAIN WILL BE BRIEF AND
THAT ANY ICE ACCUMULATION WILL BE NO MORE THAN A TRACE AND HARDLY
NOTICEABLE.
DENSE FOG...LIGHT ONSHORE S/SW-FLOW OF HIGHER DEWPOINT AIR COMBINED
WITH MOISTURE ASSOCIATED WITH SHOWERS PRESENTS POSSIBLE PATCHY DENSE
FOG CONDITIONS...THE GREATER CHANCE OF WHICH WOULD BE OVER A DEEPER
SNOWPACK AND ACROSS COLDER WATERS. INTUITION LEADS ME TO BELIEVE ANY
FOG WILL BE SHALLOW ACROSS THE INTERIOR...WITH HIGHEST CONFIDENCE OF
SOUPY CONDITIONS AROUND THE UPPER-CAPE ADJACENT TO NEAR-SHORE COLDER
WATERS. WORST CONDITIONS AROUND THE MORNING-MIDDAY TIMEFRAME PRIOR
TO COLD FRONTAL PASSAGE.
*/ LATER-HALF OF TUESDAY INTO TUESDAY NIGHT...
ARCTIC AIRMASS BUILDS ACROSS THE REGION IN WAKE OF THE COLD FRONT.
DEEP BOUNDARY-LAYER MIXING UP TO H7 YIELDS THE MIX-DOWN OF FASTER
MOMENTUM AND DRIER AIR. AN UNSTABLE ENVIRONMENT THROUGH WHICH THE
AVAILABILITY OF MOISTURE IS SOMEWHAT IN QUESTION AS TOWARDS THE
DEVELOPMENT OF RAIN / SNOW SQUALLS.
RAIN / SNOW SHOWERS...HIGH-RES GUIDANCE INDICATES THE PRESENCE OF
ACTIVITY ESPECIALLY AS MID-LEVEL ENERGY STRETCHES ACROSS THE
REGION WITHIN THE W-PERIPHERY OF A CLOSED LOW FEATURE SLIDING
OFFSHORE. DECENT SNOW-SQUALL PARAMETER VALUES SUGGESTED BY THE
BURLINGTON WFO WRF WITH THE COMBINATION OF ENHANCED ASCENT OF AN
UNSTABLE PROFILE. IT JUST REMAINS A QUESTION OF MOISTURE
AVAILABILITY...AND AS TO THE INTENSITY OF ACTIVITY OF WHICH WOULD
INFLUENCE EVAPORATIONAL COOLING PROCESSES RESULTING IN RAIN
TRANSITIONING TO SNOW. PREFER TO STICK WITH SLIGHT CHANCE POPS
INDICATING AN ISOLATED THREAT WITH AN EQUAL MIX OF RAIN AND SNOW
CHANCES. HIGHEST CONFIDENCE OF IMPACT WOULD BE ALONG W-SLOPES OF
HIGHER TERRAIN WITH OROGRAPHIC TENDENCIES WHEREAS ON THE LEE-
SIDE...DOWNSLOPING WINDS LIKELY TO LIMIT POTENTIAL.
WIND GUSTS...WILL PREVAIL A HALF-AND-HALF BLEND OF POWER REGRESSION
MIX-DOWN OF WINDS PER BUFKIT PROFILES AND A CONSENSUS BLEND OF WIND
GUST FORECAST GUIDANCE. POWER REGRESSION WAS THE STRONGER OF THE TWO
INDICATING WIND ADVISORY CRITERIA ACROSS E-COASTAL MA. NEVERTHELESS
THE BLEND YIELDED AROUND 30-35 MPH NW-GUSTS FOR INTERIOR NEW ENGLAND
AND AROUND 35-40 MPH FOR E/S-COASTAL MA AND RI...STRONGEST ACROSS
CAPE COD AND NANTUCKET WITH 40-45 MPH WIND GUSTS POSSIBLY EXCEEDING
50 MPH. WILL NOT MAKE ANY CHANGES TO THE HEADLINES. CAN NOT RULE OUT
WIND ADVISORY CRITERIA FOR THE TIP OF CAPE ANN...BUT BEING SO BRIEF
DID NOT GO WITH ANY HEADLINE. COULD ALSO SEE STRONGER WIND GUSTS
ALONG THE LEE-SLOPES OF HIGHER TERRAIN WITH DOWNSLOPING.
&&
.SHORT TERM /WEDNESDAY/...
*/ WEDNESDAY...
DRY COLD AND BLUSTERY. CONTINUED ARCTIC AIRMASS ALOFT YIELDING AN
UNSTABLE BOUNDARY-LAYER PROFILE UP TO H7 ALONG WITH STRETCHED MID-
LEVEL ENERGY THROUGH THE W-PERIPHERY OF A CLOSED LOW DEEPENING OFF
THE COAST OF NOVA SCOTIA.
RAIN/SNOW SHOWERS...ACTIVITY MAY STILL PERSIST THOUGH CONTINUE TO BE
AN ISOLATED THREAT. WILL CONTINUE WITH SLIGHT CHANCE POPS. EXPECT
ACTIVITY TO DIMINISH TOWARDS THE LATER-HALF OF THE DAY AS HIGH
PRESSURE BUILDS IN FROM THE W USHERING IN DRIER AIR WHILE EASING
WINDS.
WIND GUSTS...CONTINUED BLUSTERY WITH AROUND 30-35 MPH NW-GUSTS FOR
INTERIOR NEW ENGLAND WITH AROUND 35-40 MPH FOR E/S-COASTAL MA...WITH
GUSTS UP TO 45 MPH FOR THE OUTER-CAPE TOWARDS MIDDAY BY WHICH POINT
THE WIND ADVISORY SHOULD EXPIRE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGHLIGHTS...
* UNSEASONABLY COLD WEATHER LATE WEDNESDAY AND THURSDAY.
* COASTAL LOW MAY AFFECT SOUTHERN NEW ENGLAND FRI AND SAT...BUT
EXACT DETAILS UNCERTAIN.
* MORE COLD WEATHER EXPECTED EARLY NEXT WEEK.
OVERVIEW AND MODEL PREFERENCES...
DECENT MODEL AGREEMENT THROUGH MID WEEK...DETERIORATES LATE THIS
WEEK INTO THIS WEEKEND. OVERALL...EXPECTING A BROAD MID LEVEL
TROUGH TO PERSIST ACROSS SOUTHERN CANADA INTO THIS WEEKEND.
DIFFERENCES ARRIVE IN HOW VARIOUS HIGH LATITUDE SHORTWAVES GET
HANDLED AS THEY MOVE THROUGH THE LONGWAVE FLOW AND MOVE SOUTH.
THIS WILL IN TURN PROVIDE A LARGE INFLUENCE ON STORM TRACK AND
TIMING FRIDAY INTO SATURDAY.
TREND OF THE 17/00Z GUIDANCE HAS BEEN TO SHIFT THE PRIMARY STORM
TRACK FARTHER SOUTH FROM OUR REGION. THE GFS- AND GEFS MEAN-LED
CAMP TAKE THIS STORM SO FAR SOUTH...IT IS DOUBTFUL WE WOULD SEE
ANY PRECIPITATION AT ALL. MEANWHILE THE INTERNATIONAL MODEL
CAMP...LED BY THE CMC AND ECMWF...KEEP THIS STORM IN PLAY FOR
SOUTHERN NEW ENGLAND. SINCE WE HAVE SEEN THIS STORY PLAY OUT MANY
TIMES THE PAST TWO MONTHS...AM THINKING THERE IS ENOUGH POTENTIAL
TO WARRANT AT LEAST A CHANCE OF PRECIPITATION. PREVIOUS FORECAST
COVERED THIS WELL...AND DID NOT CHANGE IT SIGNIFICANTLY.
FOLLOWED A CONSENSUS APPROACH FOR EACH NEXT WEEK...MEANING BELOW
NORMAL TEMPERATURES RETURN...ALONG WITH DRIER WEATHER.
DETAILS...
WEDNESDAY NIGHT...ROBUST LOW LEVEL PRESSURE GRADIENT WILL REALLY
DRIVE COLDER AIR INTO OUR REGION...WITH GUSTY NORTHWEST WINDS.
LIKELY SEE 25-35 MPH WIND GUSTS. THEREFORE...WIND CHILL VALUES ARE
LIKELY TO REMAIN IN THE SINGLE DIGITS TO LOW TEENS. A FEW FLURRIES
POSSIBLE IN E SLOPES OF THE BERKSHIRES AND LITCHFIELD HILLS.
THURSDAY INTO EARLY FRI...HIGH PRESSURE WILL CREST ACROSS SOUTHERN
NEW ENGLAND THROUGH THIS PERIOD...WITH DRY WEATHER PREVAILING.
MODERATING TEMPS ARE EXPECTED...ALTHOUGH HIGHS ARE LIKELY TO
REMAIN BELOW NORMAL THURSDAY. BY FRIDAY...WITH 850 MB TEMPERATURES
REBOUND TO BETWEEN -8C AND -4C...SO WITH THE MID-MARCH SUN ONCE
AGAIN IN PLAY...WILL LIKELY SEE HIGHS CLOSER TO SEASONAL
NORMALS...MAINLY THE LOWER-MID 40S.
LATE FRIDAY INTO SATURDAY...THIS WILL BE THE PERIOD TO WATCH FOR A
POTENTIAL STORM. THERE REMAINS A LOT OF UNCERTAINTY IN THE DETAILS
WITH THIS STORM. GIVEN THE CURRENT TIMING...WOULD EXPECT
PRIMARILY A RAIN-CHANGING-TO-SNOW SCENARIO. WILL HAVE TO WATCH
THE EVOLUTION OF THIS STORM THE NEXT COUPLE OF DAYS. STILL WAY TO
EARLY TO DISCUSS POTENTIAL SNOW ACCUMULATIONS.
SUNDAY INTO MONDAY...
WHILE ASTRONOMICAL SPRING ARRIVES THIS SATURDAY...THE UPPER
LEVELS DID NOT GET THAT MEMO. THE ENERGY DIVING OUT OF THE HUDSON
BAY AREA WILL PUSH A FAIRLY ROBUST ARCTIC FRONT ACROSS OUR REGION
EARLY SUNDAY MORNING...WITH THE POSSIBILITY OF SOME SHOWERS/SNOWS
AS IT MOVES THROUGH. UNSEASONABLY COLD AIR LOOKS TO MAKE A RETURN
TO THE REGION FOR EARLY NEXT WEEK FOLLOWING THIS FRONT.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
9Z UPDATE...
.SHORT-TERM /THROUGH WEDNESDAY/...
TODAY...MODERATE CONFIDENCE.
MVFR/IFR TOWARDS AFTERNOON. -SHRA AND S-WINDS. IFR/LIFR AROUND
THE OUTER-CAPE. IMPROVING TOWARDS EVENING IN WAKE OF A COLD FRONT.
WINDS QUICKLY INCREASING OUT OF THE NW. GUSTS AROUND 30 KTS ACROSS
THE INTERIOR...40 KTS FOR THE COAST. STRONGEST ON THE OUTER CAPE
AROUND 45 KTS. ISOLATED SHRA/SHSN.
TONIGHT...HIGH CONFIDENCE.
VFR. CONTINUED BLUSTERY. PERSISTENT NW-WIND GUSTS AROUND 30 KTS
FOR THE INTERIOR...40 KTS COASTAL. ISOLATED SHRA/SHSN.
WEDNESDAY...HIGH CONFIDENCE.
VFR. WINDS SLOWLY DIMINISHING. ISOLATED SHRA/SHSN CONCLUDE.
KBOS TAF...HIGH CONFIDENCE. WILL HOLD MVFR AT LOWEST. LOW RISK OF
IFR DURING SHRA AND PRIOR TO COLD FRONTAL PASSAGE.
KBDL TAF...HIGH CONFIDENCE. WILL HOLD MVFR AT LOWEST. DO NOT
EXPECT ANY IFR CONDITIONS.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
THURSDAY...HIGH CONFIDENCE. VFR.
FRIDAY INTO SATURDAY ...MODERATE CONFIDENCE.
MVFR/IFR CONDITIONS POSSIBLE IN PERIODS OF RAIN AND SNOW.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM /THROUGH WEDNESDAY/...
EARLY-HALF OF TODAY...HIGH CONFIDENCE.
ARCTIC FRONT APPROACHES THE WATERS AHEAD OF WHICH S/SW-WINDS WILL
BE BREEZY. SEAS REMAIN BELOW 5-FEET THOUGH. MAIN CONCERN WILL BE
DENSE FOG...LIKELY MORESO ALONG THE SHORES OF THE UPPER-CAPE.
TOWARDS EVENING AND OVERNIGHT...HIGH CONFIDENCE.
IN WAKE OF THE ARCTIC FRONT...NW-WINDS INCREASING IN EXCESS OF
GALE FORCE WITH GUSTS OF AROUND 40-45 KTS. VISIBILITY QUICKLY
IMPROVES BUT SEAS BUILD 10-12 FEET ON THE OUTER WATERS. FREEZING
SPRAY LIKELY WITH POSSIBLE MODERATE AROUND THE SHORES OF THE
UPPER-CAPE. GALE WARNINGS IN PLACE. WILL HOLD OFF ON ANY FREEZING
SPRAY HEADLINES AND ALLOW THE DAY-SHIFT TO RE-EVALUATE.
WEDNESDAY...HIGH CONFIDENCE.
BLUSTERY WITH NW-GUSTS AROUND 35-40 KTS SLOWLY DIMINISHING. THERE
STILL WILL REMAIN A FREEZING SPRAY THREAT. SEAS STILL ROUGH AROUND
8 TO 10 FEET ON THE OUTER WATERS. GALE WARNINGS WILL CONTINUE
THROUGH THE PERIOD.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
WEDNESDAY NIGHT THROUGH THURSDAY...HIGH CONFIDENCE.
STRONG NW WINDS WITH GALE FORCE GUSTS EXPECTED. GALE WARNINGS ARE
LIKELY TO BE NEEDED. OTHERWISE...ROUGH SEAS BUILDING 7-10 FT.
WINDS DIMINISH LATE WED NIGHT INTO THU...BUT SMALL CRAFT ADVISORY
LEVEL GUSTS ARE EXPECTED. FREEZING SPRAY POSSIBLE.
FRIDAY AND SATURDAY...MODERATE CONFIDENCE.
LOW PRESSURE MAY PASS NEAR 40N/70W LATE SOMETIME DURING THIS
PERIOD. THIS MAY LEAD TO A PERIOD OF BUILDING SWELLS FIRST ON THE
SOUTHERN OCEAN WATERS...THEN SNEAKING INTO THE EASTERN WATERS AS
WELL. WAVE HEIGHTS UP TO 7-8 FT POSSIBLE. DEPENDING ON THE LOW
PRESSURE TRACK...GALE OR AT THE VERY LEAST SMALL CRAFT ADVISORY
WIND GUSTS ARE POSSIBLE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WIND ADVISORY FROM 6 PM THIS EVENING TO 2 PM EDT WEDNESDAY FOR
MAZ022-024.
RI...NONE.
MARINE...GALE WARNING FROM 5 PM THIS AFTERNOON TO 6 PM EDT WEDNESDAY
FOR ANZ230>235-237-250-251-254>256.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM EDT WEDNESDAY
FOR ANZ236.
&&
$$
SYNOPSIS...BELK/SIPPRELL
NEAR TERM...SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...BELK
AVIATION...BELK/SIPPRELL
MARINE...BELK/SIPPRELL
AREA FORECAST DISCUSSION
NWS NEW YORK NY
424 AM EDT TUE MAR 17 2015
.SYNOPSIS...
LOW PRESSURE WILL PASS THROUGH NORTHERN NEW ENGLAND THIS
MORNING...DRAGGING A STRONG COLD FRONT ACROSS THE AREA. HIGH
PRESSURE BUILDS IN FROM THE UPPER MIDWEST TUESDAY NIGHT THROUGH
THURSDAY. A COASTAL LOW PRESSURE SYSTEM MAY IMPACT THE AREA
FRIDAY INTO FRIDAY NIGHT...FOLLOWED BY A COLD FRONT PASSAGE LATE
SATURDAY. HIGH PRESSURE BUILDS TOWARDS THE REGION FROM THE GREAT
LAKES SUNDAY INTO MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CURRENT WV IMAGERY INDICATING SHORTWAVE TRACKING ACROSS THE SRN
PORTION OF THE SE CANADIAN PROVINCES EARLY THIS MORNING. SFC LOW
PRES IS DEVELOPING IN RESPONSE TO THIS AND WILL TRACK ACROSS NRN
NEW ENGLAND THIS MORNING...DRAGGING A STRONG COLD FRONT THROUGH
THE AREA.
LATEST RADAR IMAGERY IS INDICATING SOME LIGHT RETURNS ACROSS THE
AREA WHICH ARE GRADUALLY FILLING IN DUE TO ISENTROPIC LIFT. JUST
STARTING TO SEE OBS REPORT PCPN SO CHC POPS SHOULD SUFFICE THROUGH
09Z. CHANCES THEN INCREASE DUE TO CONTINUING WAA AND THE
APPROACHING FRONT. HRRR AND RUC WERE FOLLOWED CLOSELY AS THEY HAD
THE BEST HANDLE ON THE SITUATION. HIGHEST POPS STILL EXPECTED
ACROSS SOUTHERN CT AND EASTERN LONG ISLAND AND DECREASING
PERCENTAGES TO THE W.
RAIN ENDS FROM W TO E LATE THIS MORNING/EARLY AFTN WITH THE
PASSAGE OF THE COLD FRONT...ALTHOUGH NW WINDS WILL INCREASE DUE TO
THE COMBINATION OF STRONG CAA AND A TIGHTENING PRES GRADIENT
BETWEEN RAPID INTENSIFICATION OF THE OFFSHORE LOW TO THE NE AND
STRONG CANADIAN HIGH PRES BUILDING TO THE W. WINDS ARE EXPECTED TO
RANGE FROM 15 TO 25 MPH WITH GUSTS 40 TO 45 MPH. WE ARE CLOSE TO
WIND ADVSY BUT FALL JUST SHORT...ALTHOUGH SOME OF THE MORE EXPOSED
AREAS COULD REACH IT.
HIGHS ARE CHALLENGING TODAY. THINK THE MAVS ARE WAY TOO HIGH WITH
THE CLOUD COVER...PCPN AND COLD FRONT COMING THROUGH BETWEEN 15Z
AND 18Z. SO CHOSE TO BLEND THE COOLER GUIDANCE. HIGHS WILL DEPEND
ON HOW QUICKLY COLDER AIR STARTS FILTERING IN...WHICH MODELS ARE
IN GOOD AGREEMENT ABOUT BEING AROUND 18Z.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
TIGHT PRES GRADIENT REMAINS ACROSS THE REGION INTO WED BEFORE
FINALLY STARTING TO RELAX DURING WED AFTN. GUSTY NW WINDS WILL
CONTINUE DURING THIS TIME...ALTHOUGH THE STRONGEST WINDS WILL HAVE
PASSED.
DEEP NW FLOW WILL SEND WEAK SHORTWAVES THROUGH THE FLOW AS WELL.
MODELS ARE HINTING AT SCT SHOWER ACTIVITY TO THE N AND W OF THE
AREA...BUT NOT CONVINCED IT WILL MAKE IT OVER THE MOUNTAINS DUE TO
DOWNSLOPING. THEREFORE HAVE INCREASED CLOUDS...BUT HAVE KEPT THE
FORECAST DRY.
LOWS TONIGHT WILL BE WELL BELOW NORMAL...RANGING FROM UPPER TEENS
TO AROUND 20 INLAND...LOWER TO MID 20S AT THE COAST...EXCEPT MID
TO UPPER 20S IN THE NYC METRO. THIS IS ABOUT 10 DEGREES BELOW
NORMAL. HIGHS WED WILL CONTINUE TO BE BELOW NORMAL RANGING FROM
MID 30S TO LOWER 40S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
CANADIAN HIGH PRESSURE BUILDS OVERHEAD ON THURSDAY WITH WEAK UPPER
LEVEL RIDGING. COLD AND DRY WEATHER CONTINUES WITH TEMPERATURES NEAR
TEN DEGREES BELOW NORMAL FOR THIS TIME OF YEAR.
ATTENTION THEN TURNS TO ENERGY WITHIN THE NORTHERN BRANCH OF THE
UPPER JET DIGGING INTO THE NORTHERN STATES. THIS ENERGY WILL
FAST APPROACH ON FRIDAY SPAWNING A LOW PRESSURE OFF THE MIDDLE
ATLANTIC COAST. THERE STILL IS A FAIRLY LARGE SPREAD AMONG THE
MEDIUM RANGE OPERATIONAL MODELS AND ENSEMBLES ON THE TIMING AND
AMPLITUDE OF THIS ENERGY. THIS LEADS TO TRACK AND STRENGTH
DIFFERENCES WITH THE DEVELOPING LOW PRESSURE. THE GFS AND ITS
ENSEMBLES CONTINUE TO BE FURTHEST SOUTH WITH THE LOW KEEPING THE
HEAVIEST PRECIPITATION SOUTH OF LONG ISLAND. THE EURO AND CMC ARE
FURTHER NORTH WITH THE LOW BRINGING MORE SUBSTANTIAL PRECIPITATION
FRIDAY INTO AT LEAST THE FIRST PART OF FRIDAY NIGHT. WITH THERE
STILL REMAINING A FAIRLY LARGE SPREAD BEING DEPICTED BY THE 00Z
MODELS...HAVE OPTED TO STAY WITH HIGH CHANCE POPS FOR THIS FORECAST
PACKAGE.
COMPLICATED PTYPE FORECAST AS THE COLD AIR SOURCE FROM THE SURFACE
HIGH PRESSURE SHIFTS OFFSHORE DURING THE DAY FRIDAY ALLOWING SURFACE
WINDS TO BECOME EAST OR EVEN SOUTHEAST WARMING THE BOUNDARY LAYER.
SOME MID LEVEL WARMTH IS ALSO POSSIBLE FURTHER COMPLICATING THE
PTYPE...HAVE MAINTAINED CONSISTENT WORDING FROM PREVIOUS FORECAST OF
RAIN AND SNOW DUE TO CONTINUED UNCERTAINTY IN THERMAL PROFILES.
THE LOW QUICKLY MOVES OFFSHORE LATE FRIDAY NIGHT FOLLOWED BY THE
APPROACH OF ANOTHER COLD FRONT ON SATURDAY. TEMPERATURES MAY
APPROACH NORMAL LEVELS BRIEFLY ON SATURDAY AHEAD OF THE FRONT.
CURRENTLY FORECASTING SLIGHT CHANCE POPS WITH THE FRONT PASSAGE
SATURDAY NIGHT. CANADIAN HIGH PRESSURE THEN BUILDS INTO THE REGION
SUNDAY INTO MONDAY WITH TEMPERATURES FALLING BACK BELOW NORMAL.
TEMPERATURES SHOULD AVERAGE AROUND TEN DEGREES BELOW NORMAL SUNDAY
INTO MONDAY.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
LOW PRES PASSING NORTH OF THE AREA WILL DRAG A WARM FRONT THROUGH
THE REGION EARLY THIS MORNING...AND THEN A COLD FRONT ACROSS THE
REGION THIS AFTERNOON.
RAIN THIS MORNING WITH MVFR AND LOCAL IFR CONDS...MAINLY ACROSS
NORTHERN TERMINALS.
RAIN ENDS FROM 14-16Z WITH PASSAGE OF COLD FRONT AND CONDS IMPROVE
TO VFR.
WINDS VEER TO THE NW AND INCREASE TO 15-20 KT WITH 20-30 KT GUSTS
BY MIDDAY...AND THEN TO 20-25 KT WITH 30-35 KT GUSTS BY LATE
AFTERNOON. WINDS GRADUALLY DIMINISH TONIGHT.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM THE LEFT OF 310 MAG TO THE RIGHT. WINDS
INCREASE TO AROUND 15 KT WITH GUSTS UP TO 25 KT BY 18Z...AND THEN
FURTHER INCREASE TO 20-25 KT WITH 30-35 KT GUSTS BY 21Z.
KLGA FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM THE LEFT OF 310 MAG TO THE RIGHT. WINDS
INCREASE TO AROUND 15 KT WITH GUSTS UP TO 25 KT BY 18Z...AND THEN
FURTHER INCREASE TO 20-25 KT WITH 30-35 KT GUSTS BY 21Z.
KEWR FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM THE LEFT OF 310 MAG TO THE RIGHT. WINDS
INCREASE TO AROUND 15 KT WITH GUSTS UP TO 25 KT BY 18Z...AND THEN
FURTHER INCREASE TO 20-25 KT WITH 30-35 KT GUSTS BY 21Z.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM SW TO NW. WINDS INCREASE TO AROUND 15 KT
WITH GUSTS UP TO 25 KT BY 18Z...AND THEN FURTHER INCREASE TO AROUND
20 KT WITH GUSTS UP TO 30 KT.
KHPN FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM SW TO NW. WINDS INCREASE TO AROUND 15 KT
WITH GUSTS UP TO 25 KT BY 18Z...AND THEN FURTHER INCREASE TO AROUND
20 KT WITH GUSTS UP TO 30 KT.
KISP FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF PRECIP START/END.
MODERATE CONFIDENCE IN THE WIND FORECAST WITH AMDS POSSIBLE FOR
TIMING OF WIND SHIFT FROM SW TO NW. WINDS INCREASE TO AROUND 15 KT
WITH GUSTS UP TO 25 KT BY 18Z...AND THEN FURTHER INCREASE TO AROUND
20 KT WITH GUSTS UP TO 30 KT.
OUTLOOK FOR 09Z WEDNESDAY THROUGH SATURDAY...
.TONIGHT...VFR. DIMINISHING WINDS.
.WEDNESDAY...VFR. NW WINDS 15-20 KT WITH GUSTS UP TO 30 KT.
.WEDNESDAY NIGHT...VFR. DIMINISHING WINDS.
.THURSDAY...VFR. NW WINDS 10-15 KT.
.FRIDAY...IFR POSSIBLE IN SN AND RA.
.SATURDAY...VFR.
&&
.MARINE...
BASED ON THE LATEST SOUNDINGS WHICH ARE IN GOOD AGREEMENT...HAVE
UPGRADED ALL OF THE NON-OCEAN WATERS TO A GALE WARNING. WHILE
MIXING MAY NOT BE AS HIGH AS INDICATED DUE TO THE COLD
WATERS...THE LEVEL OF 35 KT WINDS IS FAIRLY LOW IN THE SOUNDINGS.
THE WARNING BEGINS AT 18Z ALTHOUGH IT COULD BE A FEW HOURS LATER
DEPENDING ON HOW QUICKLY THE COLDER AIR STARTS FILTERING IN. HAVE
THE WARNING ENDING AT 10Z TONIGHT...ALTHOUGH IT MAY NEED TO BE
CONTINUED ON THE OCEAN WATERS INTO WED. IT IS MARGINAL WED MORNING
SO DIDN`T HAVE THE CONFIDENCE TO GO ANY FURTHER. SCA WILL LIKELY
BE NEEDED OTHERWISE WITH A GUSTY NW FLOW CONTINUING.
WINDS AND SEAS FALL BELOW SCA LEVELS WEDNESDAY NIGHT AS HIGH
PRESSURE BUILDS OVER THE WATERS. THESE CONDITIONS ARE EXPECTED TO
CONTINUE THROUGH FRIDAY MORNING LOW PRESSURE THEN DEVELOPS OFF THE
MIDDLE ATLANTIC COAST FRIDAY INTO FRIDAY NIGHT. WINDS SHOULD
CONTINUE TO STAY JUST BELOW SCA LEVELS...BUT SEAS MAY BUILD SCA
LEVELS ON THE OCEAN FRIDAY NIGHT INTO SATURDAY.
&&
.HYDROLOGY...
LESS THAN 1/4 INCH OF RAIN IS EXPECTED THIS MORNING. HIGHEST AMOUNTS
WILL BE CONFINED TO THE SRN CT...AND THE TWIN FORKS OF LI.
THE POTENTIAL EXISTS FOR 1/2 TO 1 INCH OF LIQUID EQUIVALENT ON
FRIDAY INTO FRIDAY NIGHT. SOME OF THIS MAY FALL IN THE FROZEN
STATE BEFORE CHANGING OVER TO LIQUID.
RECENT INCREASED FLOW ON RIVERS/STREAMS...PARTICULARLY ACROSS THE
LOWER HUDSON VALLEY AND SOUTHERN CT...COUPLED WITH MILD
TEMPERATURES...MAY CAUSE ICE BREAKUP/MOVEMENT INTO EARLY THIS
WEEK. THIS SHOULD MAKE ICE JAMS AND LOCALIZED FLOODING POSSIBLE.
ICE JAM FLOODING IS UNPREDICTABLE AND SUDDEN...SO INTERESTS ALONG
ICE COVERED RIVERS SHOULD MONITOR NWS FORECASTS FOR THE LATEST
INFORMATION.
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 WEB SITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...GALE WARNING FROM 2 PM THIS AFTERNOON TO 6 AM EDT WEDNESDAY
FOR ANZ330-335-338-340-345-350-353-355.
&&
$$
AREA FORECAST DISCUSSION
NWS TAUNTON MA
327 AM EDT TUE MAR 17 2015
.SYNOPSIS...
SHOWERS ANTICIPATED AHEAD OF AN ARCTIC FRONT WHICH WILL SWEEP
ACROSS SOUTHERN NEW ENGLAND DURING THE AFTERNOON HOURS BEHIND
WHICH BLUSTERY AND UNSEASONABLY COLD WEATHER WILL FOLLOW INTO
THURSDAY. A WINTER STORM MAY IMPACT THE REGION LATE FRIDAY INTO
SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
*/ EARLY-HALF OF TUESDAY...
INCREASING DIFFLUENCE ALOFT AHEAD OF A N-STREAM IMPULSE YIELDS DEEP-
LAYER LIFT ALONG THE SURFACE REFLECTION OF WARM- AND COLD-FRONTAL
BOUNDARIES OF AN ASSOCIATED CONTINENTAL AIRMASS. SHOWER ACTIVITY
WITH THE LEADING EDGE OF LOW- TO MID-LEVEL WARM NOSE ACROSS E PA
INTO UPSTATE NY HAS BEGUN TO PUSH INTO S NEW ENGLAND. WILL TAKE A
BIT OF TIME IN REACHING THE GROUND HAVING TO OVERCOME LOW-LEVEL
DRY AIR. EXPECT A SECOND-ACT OF SHOWERS TOWARDS MIDDAY ALONG AND
AHEAD OF A FOLLOW-UP COLD FRONT. STORM-TOTAL PRECIPITATION AMOUNTS
AROUND ONE- TO TWO-TENTHS.
FEEL THE HRRR HAS THE BEST HANDLE ON THE PRESENT SITUATION AND WILL
USE IT AS GUIDANCE TOWARDS POP-TRENDS GOING HIGH-CATEGORICAL. HRRR
TEMPERATURE AND DEWPOINT TRENDS ARE NOT BAD...BUT WILL NOT USE AS
FIRST-ORDER GUIDANCE. WILL BLEND WITH SOME CONSENSUS.
FREEZING RAIN...DEPENDENT ON PRECIPITATION TIMING AND WHETHER THE
COLUMN SATURATES COMPLETELY TO THE SURFACE AS THERE IS STILL A LOT
OF LOW-LEVEL DRY AIR TO OVERCOME PER 0Z CHATHAM SOUNDING. BELIEVE
CHANCES INCREASE TOWARDS MORNING AS LOW-LEVELS WETBULB AS THE COLUMN
SATURATES...THOUGH WITH A LIGHT PRECIPITATION EVENT THINKING NOT AS
SUBSTANTIAL. NEVERTHELESS...A FREEZING RAIN POTENTIAL DOES EXIST
ESPECIALLY WITHIN NESTLED VALLEYS ACROSS N MA WHERE LOWER DEWPOINT
AIR MAY REMAIN TRAPPED. THINK ANY FREEZING RAIN WILL BE BRIEF AND
THAT ANY ICE ACCUMULATION WILL BE NO MORE THAN A TRACE AND HARDLY
NOTICEABLE.
DENSE FOG...LIGHT ONSHORE S/SW-FLOW OF HIGHER DEWPOINT AIR COMBINED
WITH MOISTURE ASSOCIATED WITH SHOWERS PRESENTS POSSIBLE PATCHY DENSE
FOG CONDITIONS...THE GREATER CHANCE OF WHICH WOULD BE OVER A DEEPER
SNOWPACK AND ACROSS COLDER WATERS. INTUITION LEADS ME TO BELIEVE ANY
FOG WILL BE SHALLOW ACROSS THE INTERIOR...WITH HIGHEST CONFIDENCE OF
SOUPY CONDITIONS AROUND THE UPPER-CAPE ADJACENT TO NEAR-SHORE COLDER
WATERS. WORST CONDITIONS AROUND THE MORNING-MIDDAY TIMEFRAME PRIOR
TO COLD FRONTAL PASSAGE.
*/ LATER-HALF OF TUESDAY INTO TUESDAY NIGHT...
ARCTIC AIRMASS BUILDS ACROSS THE REGION IN WAKE OF THE COLD FRONT.
DEEP BOUNDARY-LAYER MIXING UP TO H7 YIELDS THE MIX-DOWN OF FASTER
MOMENTUM AND DRIER AIR. AN UNSTABLE ENVIRONMENT THROUGH WHICH THE
AVAILABILITY OF MOISTURE IS SOMEWHAT IN QUESTION AS TOWARDS THE
DEVELOPMENT OF RAIN / SNOW SQUALLS.
RAIN / SNOW SHOWERS...HIGH-RES GUIDANCE INDICATES THE PRESENCE OF
ACTIVITY ESPECIALLY AS MID-LEVEL ENERGY STRETCHES ACROSS THE
REGION WITHIN THE W-PERIPHERY OF A CLOSED LOW FEATURE SLIDING
OFFSHORE. DECENT SNOW-SQUALL PARAMETER VALUES SUGGESTED BY THE
BURLINGTON WFO WRF WITH THE COMBINATION OF ENHANCED ASCENT OF AN
UNSTABLE PROFILE. IT JUST REMAINS A QUESTION OF MOISTURE
AVAILABILITY...AND AS TO THE INTENSITY OF ACTIVITY OF WHICH WOULD
INFLUENCE EVAPORATIONAL COOLING PROCESSES RESULTING IN RAIN
TRANSITIONING TO SNOW. PREFER TO STICK WITH SLIGHT CHANCE POPS
INDICATING AN ISOLATED THREAT WITH AN EQUAL MIX OF RAIN AND SNOW
CHANCES. HIGHEST CONFIDENCE OF IMPACT WOULD BE ALONG W-SLOPES OF
HIGHER TERRAIN WITH OROGRAPHIC TENDENCIES WHEREAS ON THE LEE-
SIDE...DOWNSLOPING WINDS LIKELY TO LIMIT POTENTIAL.
WIND GUSTS...WILL PREVAIL A HALF-AND-HALF BLEND OF POWER REGRESSION
MIX-DOWN OF WINDS PER BUFKIT PROFILES AND A CONSENSUS BLEND OF WIND
GUST FORECAST GUIDANCE. POWER REGRESSION WAS THE STRONGER OF THE TWO
INDICATING WIND ADVISORY CRITERIA ACROSS E-COASTAL MA. NEVERTHELESS
THE BLEND YIELDED AROUND 30-35 MPH NW-GUSTS FOR INTERIOR NEW ENGLAND
AND AROUND 35-40 MPH FOR E/S-COASTAL MA AND RI...STRONGEST ACROSS
CAPE COD AND NANTUCKET WITH 40-45 MPH WIND GUSTS POSSIBLY EXCEEDING
50 MPH. WILL NOT MAKE ANY CHANGES TO THE HEADLINES. CAN NOT RULE OUT
WIND ADVISORY CRITERIA FOR THE TIP OF CAPE ANN...BUT BEING SO BRIEF
DID NOT GO WITH ANY HEADLINE. COULD ALSO SEE STRONGER WIND GUSTS
ALONG THE LEE-SLOPES OF HIGHER TERRAIN WITH DOWNSLOPING.
&&
.SHORT TERM /WEDNESDAY/...
*/ WEDNESDAY...
DRY COLD AND BLUSTERY. CONTINUED ARCTIC AIRMASS ALOFT YIELDING AN
UNSTABLE BOUNDARY-LAYER PROFILE UP TO H7 ALONG WITH STRETCHED MID-
LEVEL ENERGY THROUGH THE W-PERIPHERY OF A CLOSED LOW DEEPENING OFF
THE COAST OF NOVA SCOTIA.
RAIN/SNOW SHOWERS...ACTIVITY MAY STILL PERSIST THOUGH CONTINUE TO BE
AN ISOLATED THREAT. WILL CONTINUE WITH SLIGHT CHANCE POPS. EXPECT
ACTIVITY TO DIMINISH TOWARDS THE LATER-HALF OF THE DAY AS HIGH
PRESSURE BUILDS IN FROM THE W USHERING IN DRIER AIR WHILE EASING
WINDS.
WIND GUSTS...CONTINUED BLUSTERY WITH AROUND 30-35 MPH NW-GUSTS FOR
INTERIOR NEW ENGLAND WITH AROUND 35-40 MPH FOR E/S-COASTAL MA...WITH
GUSTS UP TO 45 MPH FOR THE OUTER-CAPE TOWARDS MIDDAY BY WHICH POINT
THE WIND ADVISORY SHOULD EXPIRE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGHLIGHTS...
* UNSEASONABLY COLD WEATHER LATE WEDNESDAY AND THURSDAY.
* COASTAL LOW MAY AFFECT SOUTHERN NEW ENGLAND FRI AND SAT BUT
EXACT DETAILS UNCERTAIN.
* MORE COLD WEATHER LOOKING POSSIBLE EARLY NEXT WEEK.
OVERVIEW AND MODEL PREFERENCES...
LOOKING AT THE LARGE SCALE PATTERN BOTH NOW AND IN THE
FUTURE...CONDITIONS LOOK RIGHT TO BRING BACK THE CONDITIONS THAT
SO DEFINED OUR RECORD/S/ BREAKING SEASON. AO/NAO/EPO ALL TREND
NEGATIVE THROUGH THE END OF THE WEEK...WITH THE PNA LEANING
POSITIVE THANKS TO REX-LIKE BLOCK ACROSS THE NW CONUS.
THEREFORE...STILL HAVE FAIRLY HIGH CONFIDENCE IN TEMPS DROPPING
BACK BELOW SEASONAL NORMALS THROUGH THE MID TERM. BUT WILL ALSO
HAVE TO WATCH...WAIT FOR IT...THE POSSIBILITY TO BOOKEND THIS COLD
SNAP WITH YET ANOTHER COASTAL STORM FOR FRI NIGHT AND SAT. PER
USUAL...THERE IS A LOT OF VARIABILITY WITH THE TRACK OF THIS
SYSTEM WHICH...ESPECIALLY GIVEN THE HIGHER MARCH SUN ANGLE...WILL
PLAY INTO THE THERMAL PROFILES. ENSEMBLES SHOW CLUSTERING INSIDE
THE 40/70 BENCHMARK /ESPECIALLY ECENS/CANADIAN ENSEMBLES/ WHILE
DETERMINISTIC GFS/ECMWF AND UKMET ARE ALL OUTSIDE OF THE
BENCHMARK. AT ODDS ARE TWO FACTORS...THE NRN STREAM INITIALIZING
WAVE HAS YET TO BE SAMPLED OVER THE LANDMASS. ALSO...INTERESTING
CUTOFF MITOSIS WITHIN THE LONGWAVE TROF OVER ERN CANADA WITH SOME
ENERGY JOINING THE WAVE MOVING IN FROM THE PACIFIC. EXACTLY HOW
THESE JOIN FORCES WILL TAKE SOME MORE TIME TO RESOLVE. FOR
NOW...AND GIVEN THE AGREEMENT IN THE MID TERM...A BLEND OF THE
COOLER/OUTSIDE DETERMINISTIC GUIDANCE WILL BE BLENDED WITH THE
WARMER/NEAR SHORE ENSEMBLES.
DETAILS...
WED AND WED NIGHT...
THAT GOOD OLE WINTER FEEL WE ALL BECAME SO FOND OF RETURNS WITH
VENGEANCE...THE ATMOSPHERE SEEMING TO IGNORE THE FACT IT IS MID
MARCH...AS IT IS WANT TO DO. H85 TEMPS WILL BE DROPPING TO BETWEEN
-15 AND -18C THROUGH THE DAY. SO IN SPITE OF DECENT MIXING AND
MARCH SUNSHINE...AMBIENT TEMPS ARE LIKELY TO STRUGGLE TO MAKE IT
INTO THE 30S. WITH HIGHS MAINLY TOPPING OUT IN THE MID 20S TO
AROUND 30. BUT WAIT...THERES MORE...NW WINDS WILL BE QUITE
BLUSTERY THANKS TO ROBUST LOW LVL PRES GRADIENT. LIKELY SEE 25-35
MPH WIND GUSTS. THEREFORE...WIND CHILL VALUES ARE LIKELY TO REMAIN
IN THE SINGLE DIGITS TO LOW TEENS. A FEW FLURRIES POSSIBLE IN E
SLOPES OF THE BERKSHIRES AND LITCHFIELD HILLS.
THU AND FRI...
HIGH PRES WILL CREST ACROSS SRN NEW ENGLAND THROUGH THIS PERIOD...
WITH DRY WX PREVAILING. MODERATING TEMPS ARE EXPECTED...ALTHOUGH
HIGHS ARE LIKELY TO REMAIN BELOW NORMAL ON THU...BUT FEEL MILD
COMPARED TO WEDNESDAY. BY FRI...WITH H85 TEMPS REBOUND TO BETWEEN
-8C AND -4C...SO WITH THE MID MARCH SUN ONCE AGAIN IN PLAY...WILL
LIKELY SEE HIGHS CLOSER TO SEASONAL NORMALS...MAINLY THE LOW-MID
40S.
FRI NIGHT INTO SAT...
THIS WILL BE THE PERIOD TO WATCH THROUGH THE NEXT FEW DAYS. FAST
EASTWARD SHIFTING SHORTWAVE EJECTING FROM THE W CONUS RIDGE IS
LIKELY TO INTERACT WITH COLD HUDSON/S BAY CUTOFF WHICH WILL SPLIT
AND SHIFT NEARER TO THE NE CONUS. MODELS CONTINUE TO INDICATE THE
FORMATION AND THEN DEEPENING OF LOW PRES FROM THE MID ATLANTIC...
TO NEAR THE 40/70 BENCHMARK BY EARLY SAT AM. THE CENTRAL PRES OF
THIS LOW LOOKS TO DROP THROUGH THE 990S TO 980S INTO THE DAY ON
SAT. AM NOTING A FAIR AMOUNT OF MID LVL F-GEN/DEFORMATION AND
ATTENDANT OMEGA THROUGH THE DENDRITE REGIME ALONG THE NE AND NW
QUADS OF THE LOW PRES AS IT PASSES...SUGGESTING POTENTIAL BANDED
SNOW SCENARIO WITHIN THE CLIMATOLOGICAL TROWAL. WHILE THIS IS ALL
NEARLY TEXTBOOK...WHAT GIVES...WILL IT BE A SNOWSTORM?
UNCERTAINTY...
AS MENTIONED ABOVE...THERE ARE ISSUES REGARDING THE EXACT TRACK
OF THIS LOW PRES...SOME SE OF THE BENCHMARK WHILE OTHERS ARE
CLOSER TO POSSIBLY EVEN OVER NANTUCKET. WITH IT BEING MID-LATE
MARCH BY THE TIME THIS STORM ARRIVES...THERMAL PROFILES ARE GOING
TO BE DIFFICULT TO NAIL DOWN UNTIL WE GET CLOSER. IT WOULD TAKE
LESS OF A WARM INTRUSION TO LIMIT SNOW POTENTIAL GIVEN THE HIGHER
SUN ANGLE. MODELS INDICATE A LOW-LVL NEARLY ISOTHERMAL LAYER
WITHIN A FEW DEGREES OF 0C. WHILE THIS MOST RECENT RUN OF THE GFS
IS COLDER...AND WOULD LIKELY BE AN ALL SNOW EVENT AWAY FROM THE
IMMEDIATE S COAST...IT/S OWN ENSEMBLES SHOW WARMER SOLUTIONS
CLOSER TO THAT OF THE ECENS AND CANADIAN ENSEMBLES. THEREFORE...
THIS COULD WELL BE A SCENARIO WHERE DYNAMIC COOLING COMES INTO
PLAY...COUPLED WITH VERY SLIGHT SHIFTS OF THE STORM TRACK. GIVEN
THAT THE BLOCKING HIGH PRES LIES MORE TO THE E OF THE DEEPENING
LOW PRES...IT/S NOT THE GREATEST SETUP TO LOCK IN THE COLD
AIR...WOULD LIKE TO SEE IT MORE TO THE N.
SNOW/RAIN/WINTRY MIX POTENTIAL...
GIVEN THE UNCERTAINTY MENTIONED ABOVE...WANT TO STRESS THAT THE
FORECAST IS LIKELY TO CHANGE OVER THE NEXT FEW DAYS...SO STAY
TUNED. GIVEN THE WARM AIR LEADS THE STRONGEST OMEGA...IF IT/S
GOING TO BE WARM..IT WILL LIKELY START AS RAIN AND THEN GRADUALLY
TRANSITION THROUGH TO SNOW BY THE DAYTIME SAT. PWATS ARE NOT
INCREDIBLY HIGH HERE...AND LOOK TO BE WITHIN 1 STD DEVIATION OF
NORMAL...AS SUCH TOTAL QPF VALUES /AND THIS WOULD INCLUDE THE
LIQUID RAIN AS/IF IT OCCURS/ RANGE MAINLY FROM 0.30 TO ABOUT 0.75
INCHES ON THE UPPER EXTREME. SO PLOWABLE SNOW NOT OUT OF THE
QUESTION SHOULD IT TRANSITION OR EVEN START AS SNOW EARLIER.
SUN INTO MON...
THE UPPER LVLS ARE NOT DONE YET THOUGH. THE ENERGY DIVING OUT OF
THE HUDSON BAY AREA WILL PUSH A FAIRLY ROBUST ARCTIC FRONT ACROSS
THE REGION ON SUN...WITH THE POSSIBILITY OF SOME SHOWERS/SNOWS AS
IT MOVES THROUGH. COLD AIR LOOKS TO MAKE A RETURN TO THE REGION
FOR EARLY NEXT WEEK FOLLOWING THIS FRONT.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
9Z UPDATE...
.SHORT-TERM /THROUGH WEDNESDAY/...
TODAY...MODERATE CONFIDENCE.
MVFR/IFR TOWARDS AFTERNOON. -SHRA AND S-WINDS. IFR/LIFR AROUND
THE OUTER-CAPE. IMPROVING TOWARDS EVENING IN WAKE OF A COLD FRONT.
WINDS QUICKLY INCREASING OUT OF THE NW. GUSTS AROUND 30 KTS ACROSS
THE INTERIOR...40 KTS FOR THE COAST. STRONGEST ON THE OUTER CAPE
AROUND 45 KTS. ISOLATED SHRA/SHSN.
TONIGHT...HIGH CONFIDENCE.
VFR. CONTINUED BLUSTERY. PERSISTENT NW-WIND GUSTS AROUND 30 KTS
FOR THE INTERIOR...40 KTS COASTAL. ISOLATED SHRA/SHSN.
WEDNESDAY...HIGH CONFIDENCE.
VFR. WINDS SLOWLY DIMINISHING. ISOLATED SHRA/SHSN CONCLUDE.
KBOS TAF...HIGH CONFIDENCE. WILL HOLD MVFR AT LOWEST. LOW RISK OF
IFR DURING SHRA AND PRIOR TO COLD FRONTAL PASSAGE.
KBDL TAF...HIGH CONFIDENCE. WILL HOLD MVFR AT LOWEST. DO NOT
EXPECT ANY IFR CONDITIONS.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
THURSDAY...HIGH CONFIDENCE.
VFR. 25-35 KT NW WINDS LIKELY WED.
FRIDAY INTO SATURDAY ...MODERATE CONFIDENCE.
MVFR/IFR CONDITIONS LIKELY IN PERIODS OF RAIN AND SNOW.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT TERM /THROUGH TUESDAY NIGHT/...
EARLY-HALF OF TODAY...HIGH CONFIDENCE.
ARCTIC FRONT APPROACHES THE WATERS AHEAD OF WHICH S/SW-WINDS WILL
BE BREEZY. SEAS REMAIN BELOW 5-FEET THOUGH. MAIN CONCERN WILL BE
DENSE FOG...LIKELY MORESO ALONG THE SHORES OF THE UPPER-CAPE.
TOWARDS EVENING AND OVERNIGHT...HIGH CONFIDENCE.
IN WAKE OF THE ARCTIC FRONT...NW-WINDS INCREASING IN EXCESS OF
GALE FORCE WITH GUSTS OF AROUND 40-45 KTS. VISIBILITY QUICKLY
IMPROVES BUT SEAS BUILD 10-12 FEET ON THE OUTER WATERS. FREEZING
SPRAY LIKELY WITH POSSIBLE MODERATE AROUND THE SHORES OF THE
UPPER-CAPE. GALE WARNINGS IN PLACE. WILL HOLD OFF ON ANY FREEZING
SPRAY HEADLINES AND ALLOW THE DAY-SHIFT TO RE-EVALUATE.
WEDNESDAY...HIGH CONFIDENCE.
BLUSTERY WITH NW-GUSTS AROUND 35-40 KTS SLOWLY DIMINISHING. THERE
STILL WILL REMAIN A FREEZING SPRAY THREAT. SEAS STILL ROUGH AROUND
8 TO 10 FEET ON THE OUTER WATERS. GALE WARNINGS WILL CONTINUE
THROUGH THE PERIOD.
OUTLOOK...WEDNESDAY THROUGH SATURDAY...
WEDNESDAY NIGHT THROUGH THURSDAY...HIGH CONFIDENCE.
STRONG NW WINDS WITH GALE FORCE GUSTS EXPECTED. GALE WARNINGS ARE
LIKELY TO BE NEEDED. OTHERWISE...ROUGH SEAS BUILDING 7-10 FT.
WINDS DIMINISH ON THU...BUT SMALL CRAFT ADVISORY LEVEL GUSTS ARE
EXPECTED. FREEZING SPRAY POSSIBLE.
FRIDAY AND SATURDAY...MODERATE CONFIDENCE.
LOW PRES WILL PASS NEAR 40N/70W LATE SAT NIGHT. THIS MAY LEAD TO
A PERIOD OF BUILDING SWELLS FIRST ON THE SRN OCEAN WATERS THEN
SNEAKING INTO THE E WATERS AS WELL. WAVE HEIGHTS UP TO 7-8 FT
POSSIBLE. DEPENDING ON THE LOW PRESSURE TRACK...GALE OR AT THE
VERY LEAST SMALL CRAFT ADVISORY WIND GUSTS ARE POSSIBLE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...WIND ADVISORY FROM 6 PM THIS EVENING TO 5 AM EDT WEDNESDAY FOR
MAZ022-024.
RI...NONE.
MARINE...GALE WARNING FROM 5 PM THIS AFTERNOON TO 9 AM EDT WEDNESDAY
FOR ANZ232-255-256.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 5 AM EDT WEDNESDAY
FOR ANZ230-233>235-237.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 6 PM EDT WEDNESDAY
FOR ANZ231-250-251-254.
GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM EDT WEDNESDAY
FOR ANZ236.
&&
$$
SYNOPSIS...DOODY/SIPPRELL
NEAR TERM...SIPPRELL
SHORT TERM...SIPPRELL
LONG TERM...DOODY
AVIATION...DOODY/SIPPRELL
MARINE...DOODY/SIPPRELL
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
246 PM CDT TUE MAR 17 2015
.SYNOPSIS...
ISSUED AT 245 PM CDT TUE MAR 17 2015
HIGH CIRRUS CLOUDS BISECTED THE STATE OF IOWA TODAY AND WERE
MOVING INTO CENTRAL IL. THIS MOISTURE WAS MOVING INTO THE STATE
FROM THE PACIFIC. AT THE SURFACE A CANADIAN HIGH PRESSURE WAS
ADVECTING INTO THE AREA FROM THE NORTH AND WEST TODAY. EXTREMELY
DRY AIR...LOCATED OVER WISCONSIN WAS FILTERING INTO THE CWA. THIS
WAS LEADING TO EXTREMELY LOW RH VALUES ACROSS THE AREA. MANY SITES
HAVE DEWPOINTS IN THE ZERO DIGITS. NEEDLESS TO SAY...THE MOISTURE
ALOFT WILL NOT MAKE IT TO THE GROUND.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 245 PM CDT TUE MAR 17 2015
MAIN FORECAST CONCERN FOR THE SHORT TERM FORECAST ARE THE
TEMPERATURES AND DEWPOINTS THROUGH THE PERIOD. WITH COMPUTER
GUIDANCE VIRTUALLY USELESS FOR THE DEWPOINTS TODAY THE FORECAST
HAS BEEN A CHALLENGE TO SAY THE LEAST. HIRES HOURLY MODELS SEEM TO
HAVE THE BEST HANDLE.
NONE OF THE 12Z REGIONAL AND SPECTRAL MODELS COME EVEN CLOSE TO
HANDLING THE DRY AIR WELL...SO FORCED TO USE THE HRRR AND THE RUC
FOR DEW POINT TEMPS. THE DRY AIR SHOULD CONTINUE TO AFFECT THE AREA
UNTIL MORE OF AN EASTERLY COMPONENT OF WIND CAN ADVECT LAKE
MICHIGAN MOISTURE INTO THE AREA. THIS SHOULD HAPPEN OVERNIGHT AND
CLOSER TO SUNRISE. AS A RESULT...USED THE RUC AND HRRR DEWPOINTS
AND MANUALLY ADJUSTED FROM THERE. MODELS HAVE WARMED UP TONIGHT
WITH LOWS. NOT CONVINCED OF THIS...SO WENT WITH LOW END OF
GUIDANCE...SINCE WE COULD DROP FAST TONIGHT TEMP WISE BEFORE THE
CLOUDS MOVE IN.
TEMPERATURES TOMORROW WILL BE AROUND NORMAL LIKE TODAY. I
POPULATED WITH THE ALLBLEND...WHICH WAS SLIGHTLY LOWER THAN THE
SUPERBLEND. THOUGHT THIS WAS A BETTER COMPROMISE WITH THE CLOUDS
IN PLACE DURING PEAK HEATING. WE SHOULDN`T BE AS DRY AS WE WERE
TODAY...SO THE THREAT OF HIGH FIRE DANGER SHOULD GO AWAY TONIGHT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 245 PM CDT TUE MAR 17 2015
OVERVIEW...NORTHWEST MID-LEVEL FLOW WILL RESULT IN COOLER
TEMPERATURES THROUGH THE UPCOMING WEEKEND AS 1000-500MB THICKNESS
VALUES REMAIN NEAR OR BELOW 540 DAM AND CYCLONIC FLOW ALOFT
PERSISTS. THE EXCEPTION WILL BE ON FRIDAY WHEN WEST/SOUTHWEST WINDS
WILL BOOST TEMPS INTO THE UPPER 50S TO LOWER 60S.
THURSDAY...COOL AIR WILL BE IN PLACE AS 1030 MB SFC HIGH BUILDS IN.
WENT A FEW DEGREES BELOW SUPERBLEND SINCE RAW MODELS TEND TO PERFORM
BETTER IN THESE PATTERN SHIFT REGIMES. HIGHS WILL RANGE FROM THE
UPPER 40S TO LOWER 50S. 850 MB TEMPS WILL HOVER NEAR -4 C.
SLIGHT CHANCE FOR LIGHT RAIN SHOWERS WED NIGHT INTO THU NIGHT ACROSS
THE S/SE CWA BUT THIS SYSTEM LOOKS DISORGANIZED AND MOISTURE STARVED.
FRIDAY...WARMEST DAY OF THIS EXTENDED PERIOD. HIGHS SHOULD AVG IN
THE LOW 60S AS WAA DEVELOPS AHEAD OF ANOTHER APPROACHING COLD FRONT.
850 MB TEMPS COULD PEAK IN THE +4-8 C RANGE WITH 1000-500 MB
THICKNESSES AROUND 550 DAM.
SATURDAY AND SUNDAY...MODELS IN GOOD AGREEMENT SLIDING A SPRAWLING
1030-1035 MB SFC HIGH INTO THE MIDWEST. EXPECT A STEADY NW FLOW ON
SAT AND THEN EAST WINDS ON SUN. 850 MB TEMPS ARE FORECAST TO FALL AS
LOW AS -8 C PER THE ECMWF BY SAT NIGHT. AGAIN WENT SEVERAL DEGREES
BELOW THE SUPERBLEND WHICH IS LIKELY TOO HEAVILY WEIGHTED BY THE
BIAS CORRECTED GRIDS IN A SHIFT TO COOLER WEATHER LIKE THIS.
MONDAY...VORTICITY MAX IN THE NW FLOW MAY BRING LIGHT PRECIP INTO
THE REGION. 40S FOR HIGHS BUT PRECIP CHANCES ARE STILL VERY LOW.
THE NEXT WARM-UP WILL NOT OCCUR UNTIL THE RETURN FLOW KICKS
IN...POSSIBLY BY THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1250 PM CDT TUE MAR 17 2015
CEILINGS AND VSBYS TO REMAIN AT VFR THROUGH THE PERIOD. A SLUG OF
MID LEVEL MOISTURE WILL MOVE INTO THE AREA ALONG WITH SURFACE HIGH
PRESSURE. THIS WILL LEAD TO MIDLEVEL CLOUDS AND THEN A WIND SHIFT
WITH WINDS STARTING TO SLACKEN DURING THE OVERNIGHT HOURS. EXPECT
THE WINDS TO SHIFT FROM NORTH TO A SE WIND TOMORROW AM.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...UTTECH
AVIATION...GIBBS
AREA FORECAST DISCUSSION...UPDATED
NWS QUAD CITIES IA IL
1255 PM CDT TUE MAR 17 2015
.UPDATE...
ISSUED AT 1058 AM CDT TUE MAR 17 2015
DRIER THAN FORECAST AIR IS ADVECTING INTO THE AREA FROM THE NORTH
AND EAST TODAY. THIS AIRMASS WAS LEADING TO SINGLE DIGIT DEWPOINTS
TO OUR NORTH IN BOSCOBEL AND PDC. THIS AIRMASS WILL ADVECT DOWN
HERE. ONLY THE RECENT HRRR AND RUC MODELS SEEM TO HAVE THIS DRY
AIR. THE 12Z NAM IS TOO MOIST...BUT THE BCNAM SEEMS TO HAVE A
BETTER IDEA. WITH THE CLEAR SKIES AND MIXING THIS AFTERNOON
EXPECT THE DRYING TO CONTINUE. AS A RESULT...THE NEW GFDI VALUES
WILL LEAD TO VERY HIGH FIRE DANGER FROM I80 SOUTH. NO OTHER
CHANGES TO THE FORECAST ARE EXPECTED AT THIS TIME.
&&
.SYNOPSIS...
ISSUED AT 353 AM CDT TUE MAR 17 2015
COLD FRONT HAS PUSHED SOUTH OF THE CWA...WITH GUSTY NORTHERLY WINDS
(15-30 KTS) IN TIGHT PRESSURE GRADIENT AHEAD OF STRONG 1040 MB
PLAINS HIGH PRESSURE USHERING IN COLDER AIR. SATELLITE AND OBS SHOW
AREA OF STRATOCU WITH MVFR CIGS OVER PORTIONS OF NORTHERN IL ATTENDANT
TO REMNANT PNEUMONIA FRONT WHICH PUSHED OFF WEST SHORE OF LAKE MI
LAST EVENING. OTHERWISE... MAINLY BOUTS OF MID TO HIGH LEVEL CLOUDINESS
WITH SOME MID LEVEL FRONTOGENETICAL FORCING ATTENDANT TO RIGHT ENTRANCE
REGION OF JET FROM UPPER MIDWEST TO GREAT LAKES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM CDT TUE MAR 17 2015
DRY AND MUCH COLDER AS CANADIAN HIGH PRESSURE RIDGE BUILDS IN OVER THE
NEXT 24 HRS.
TODAY...WANING MID LEVEL FORCING ATTENDANT TO DEPARTING UPPER JET INTO
GREAT LAKES SHOULD LEAD TO DECREASING CLOUDINESS AS DAY PROGRESSES
WITH GENERALLY SUNNY/MOSTLY SUNNY SKIES THIS AFTERNOON. WINDS WILL REMAIN
GUSTY 15-25 KTS THOUGH SOME DECREASE ANTICIPATED THIS AFTERNOON AS THE
HIGH BEGINS TO BUILD TOWARD THE AREA. TEMPS WILL LIKELY CONTINUE TO FALL
UNTIL MID AM BEFORE LEVELING OFF THEN EXPECT SOME DIURNAL RECOVERY THIS
AFTERNOON AND STAYED NEAR THE WARMER SIDE OF GUIDANCE FOR HIGHS WITH
DRY GROUND AND STRENGTHENING MID MARCH SUN. RAP/GFS/NAM BUFR SOUNDINGS
SHOW DEEP MIXING TO NEAR 850 MB... WHICH BROUGHT TO SURFACE SUPPORTS RANGE
OF HIGHS FROM MID 40S NORTH TO MID 50S FAR SOUTH.
TONIGHT...MAINLY CLEAR SKIES THIS EVENING THEN INCREASING MID/HIGH CLOUDS
OVERNIGHT IN DEVELOPING MID LEVEL WARM ADVECTION. LOWS WILL BE QUITE
CHALLENGING AND DEPENDENT ON EXTENT OF CLOUD COVER... AND FORECAST LOWS
ARE NEAR GUIDANCE BLEND AND GENERALLY IN THE 20S. WITH LIGHT WINDS AND
DRY GROUND COULD SEE SOME FAVORED DRAINAGE SITES NORTH/EAST CWA DIP DOWN
INTO THE LOWER 20S IF SKIES WERE TO REMAIN MAINLY CLEAR FOR LONGER THAN
FORECAST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 353 AM CDT TUE MAR 17 2015
DRY CONDITIONS WILL CONTINUE ON WEDNESDAY WITH TEMPERATURES NEAR
NORMAL.
WEDNESDAY NIGHT TWO SEPARATE STORM SYSTEMS WILL MOVE THROUGH THE
MIDWEST. THE NORTHERN STORM HAS LIMITED MOISTURE BUT MIGHT PRODUCE
SOME ISOLATED FLURRIES IN THE HIGHWAY 20 CORRIDOR AFTER MIDNIGHT.
THE SOUTHERN STORM HAS PLENTY OF MOISTURE BUT THE BETTER FORCING
REMAINS ACROSS CENTRAL MISSOURI AND SOUTHERN ILLINOIS. SOME VERY
LIGHT RAIN OR SPRINKLES/FLURRIES MAY CATCH THE EXTREME SOUTHERN
PARTS OF HANCOCK AND MCDONOUGH COUNTIES.
DRY CONDITIONS ARE THEN EXPECTED THURSDAY/THURSDAY NIGHT AS HIGH
PRESSURE SETTLES OVER THE GREAT LAKES. TEMPERATURES SHOULD BE NEAR
NORMAL.
FRIDAY ON...
THE MODEL CONSENSUS HAS QUIET AND DRY CONDITIONS FOR THE AREA FRIDAY
THROUGH SUNDAY NIGHT. SEVERAL DRY FRONTAL PASSAGES ARE EXPECTED
RESULTING IN ONLY AN INCREASE IN CLOUD COVER. TEMPERATURES ABOVE
NORMAL ARE EXPECTED ON FRIDAY...FOLLOWED BY NEAR NORMAL TEMPERATURES
ON SATURDAY AND BELOW NORMAL TEMPERATURES ON SUNDAY.
ON MONDAY THE MODEL CONSENSUS HAS SLIGHT CHANCE POPS OVER THE
SOUTHWEST QUARTER OF THE AREA AS A STORM SYSTEM MOVES FROM THE
PLAINS INTO THE LOWER OHIO VALLEY. THERE ARE DISAGREEMENTS AMONG THE
MODELS ON WHERE THIS STORM SYSTEM WILL TRACK. THUS IT IS POSSIBLE
THAT MONDAY MIGHT BE DRY. TEMPERATURES WILL BE AROUND OR SLIGHTLY
BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1250 PM CDT TUE MAR 17 2015
CEILINGS AND VSBYS TO REMAIN AT VFR THROUGH THE PERIOD. A SLUG OF
MID LEVEL MOISTURE WILL MOVE INTO THE AREA ALONG WITH SURFACE HIGH
PRESSURE. THIS WILL LEAD TO MIDLEVEL CLOUDS AND THEN A WIND SHIFT
WITH WINDS STARTING TO SLACKEN DURING THE OVERNIGHT HOURS. EXPECT
THE WINDS TO SHIFT FROM NORTH TO A SE WIND TOMORROW AM.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...GIBBS
SYNOPSIS...05
SHORT TERM...05
LONG TERM...08
AVIATION...GIBBS
AREA FORECAST DISCUSSION...UPDATED
NWS QUAD CITIES IA IL
1106 AM CDT TUE MAR 17 2015
.UPDATE...
ISSUED AT 1058 AM CDT TUE MAR 17 2015
DRIER THAN FORECAST AIR IS ADVECTING INTO THE AREA FROM THE NORTH
AND EAST TODAY. THIS AIRMASS WAS LEADING TO SINGLE DIGIT DEWPOINTS
TO OUR NORTH IN BOSCOBEL AND PDC. THIS AIRMASS WILL ADVECT DOWN
HERE. ONLY THE RECENT HRRR AND RUC MODELS SEEM TO HAVE THIS DRY
AIR. THE 12Z NAM IS TOO MOIST...BUT THE BCNAM SEEMS TO HAVE A
BETTER IDEA. WITH THE CLEAR SKIES AND MIXING THIS AFTERNOON
EXPECT THE DRYING TO CONTINUE. AS A RESULT...THE NEW GFDI VALUES
WILL LEAD TO VERY HIGH FIRE DANGER FROM I80 SOUTH. NO OTHER
CHANGES TO THE FORECAST ARE EXPECTED AT THIS TIME.
&&
.SYNOPSIS...
ISSUED AT 353 AM CDT TUE MAR 17 2015
COLD FRONT HAS PUSHED SOUTH OF THE CWA...WITH GUSTY NORTHERLY WINDS
(15-30 KTS) IN TIGHT PRESSURE GRADIENT AHEAD OF STRONG 1040 MB
PLAINS HIGH PRESSURE USHERING IN COLDER AIR. SATELLITE AND OBS SHOW
AREA OF STRATOCU WITH MVFR CIGS OVER PORTIONS OF NORTHERN IL ATTENDANT
TO REMNANT PNEUMONIA FRONT WHICH PUSHED OFF WEST SHORE OF LAKE MI
LAST EVENING. OTHERWISE... MAINLY BOUTS OF MID TO HIGH LEVEL CLOUDINESS
WITH SOME MID LEVEL FRONTOGENETICAL FORCING ATTENDANT TO RIGHT ENTRANCE
REGION OF JET FROM UPPER MIDWEST TO GREAT LAKES.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 353 AM CDT TUE MAR 17 2015
DRY AND MUCH COLDER AS CANADIAN HIGH PRESSURE RIDGE BUILDS IN OVER THE
NEXT 24 HRS.
TODAY...WANING MID LEVEL FORCING ATTENDANT TO DEPARTING UPPER JET INTO
GREAT LAKES SHOULD LEAD TO DECREASING CLOUDINESS AS DAY PROGRESSES
WITH GENERALLY SUNNY/MOSTLY SUNNY SKIES THIS AFTERNOON. WINDS WILL REMAIN
GUSTY 15-25 KTS THOUGH SOME DECREASE ANTICIPATED THIS AFTERNOON AS THE
HIGH BEGINS TO BUILD TOWARD THE AREA. TEMPS WILL LIKELY CONTINUE TO FALL
UNTIL MID AM BEFORE LEVELING OFF THEN EXPECT SOME DIURNAL RECOVERY THIS
AFTERNOON AND STAYED NEAR THE WARMER SIDE OF GUIDANCE FOR HIGHS WITH
DRY GROUND AND STRENGTHENING MID MARCH SUN. RAP/GFS/NAM BUFR SOUNDINGS
SHOW DEEP MIXING TO NEAR 850 MB... WHICH BROUGHT TO SURFACE SUPPORTS RANGE
OF HIGHS FROM MID 40S NORTH TO MID 50S FAR SOUTH.
TONIGHT...MAINLY CLEAR SKIES THIS EVENING THEN INCREASING MID/HIGH CLOUDS
OVERNIGHT IN DEVELOPING MID LEVEL WARM ADVECTION. LOWS WILL BE QUITE
CHALLENGING AND DEPENDENT ON EXTENT OF CLOUD COVER... AND FORECAST LOWS
ARE NEAR GUIDANCE BLEND AND GENERALLY IN THE 20S. WITH LIGHT WINDS AND
DRY GROUND COULD SEE SOME FAVORED DRAINAGE SITES NORTH/EAST CWA DIP DOWN
INTO THE LOWER 20S IF SKIES WERE TO REMAIN MAINLY CLEAR FOR LONGER THAN
FORECAST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 353 AM CDT TUE MAR 17 2015
DRY CONDITIONS WILL CONTINUE ON WEDNESDAY WITH TEMPERATURES NEAR
NORMAL.
WEDNESDAY NIGHT TWO SEPARATE STORM SYSTEMS WILL MOVE THROUGH THE
MIDWEST. THE NORTHERN STORM HAS LIMITED MOISTURE BUT MIGHT PRODUCE
SOME ISOLATED FLURRIES IN THE HIGHWAY 20 CORRIDOR AFTER MIDNIGHT.
THE SOUTHERN STORM HAS PLENTY OF MOISTURE BUT THE BETTER FORCING
REMAINS ACROSS CENTRAL MISSOURI AND SOUTHERN ILLINOIS. SOME VERY
LIGHT RAIN OR SPRINKLES/FLURRIES MAY CATCH THE EXTREME SOUTHERN
PARTS OF HANCOCK AND MCDONOUGH COUNTIES.
DRY CONDITIONS ARE THEN EXPECTED THURSDAY/THURSDAY NIGHT AS HIGH
PRESSURE SETTLES OVER THE GREAT LAKES. TEMPERATURES SHOULD BE NEAR
NORMAL.
FRIDAY ON...
THE MODEL CONSENSUS HAS QUIET AND DRY CONDITIONS FOR THE AREA FRIDAY
THROUGH SUNDAY NIGHT. SEVERAL DRY FRONTAL PASSAGES ARE EXPECTED
RESULTING IN ONLY AN INCREASE IN CLOUD COVER. TEMPERATURES ABOVE
NORMAL ARE EXPECTED ON FRIDAY...FOLLOWED BY NEAR NORMAL TEMPERATURES
ON SATURDAY AND BELOW NORMAL TEMPERATURES ON SUNDAY.
ON MONDAY THE MODEL CONSENSUS HAS SLIGHT CHANCE POPS OVER THE
SOUTHWEST QUARTER OF THE AREA AS A STORM SYSTEM MOVES FROM THE
PLAINS INTO THE LOWER OHIO VALLEY. THERE ARE DISAGREEMENTS AMONG THE
MODELS ON WHERE THIS STORM SYSTEM WILL TRACK. THUS IT IS POSSIBLE
THAT MONDAY MIGHT BE DRY. TEMPERATURES WILL BE AROUND OR SLIGHTLY
BELOW NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 550 AM CDT TUE MAR 17 2015
VFR CONDITIONS EXPECTED THROUGH AT LEAST THE NEXT 24+ HRS. NORTHERLY
WINDS 10-20+ KTS AND GUSTY WILL DIMINISH TO AROUND 10 KTS THIS
AFTERNOON THEN BECOME LIGHT TONIGHT AS HIGH PRESSURE BUILDS IN.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...GIBBS
SYNOPSIS...05
SHORT TERM...05
LONG TERM...08
AVIATION...05
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
617 PM CDT WED MAR 18 2015
...UPDATED AVIATION SECTION...
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 309 PM CDT WED MAR 18 2015
THE 12Z SHORT/MEDIUM RANGE MODELS CONTINUE TO INDICATE SEVERAL
SYNOPTIC/MESOSCALE FORCING PARAMETERS COMING TOGETHER TO BRING A
SIGNIFICANT PRECIPITATION EVENT TO SOUTHWEST KANSAS LATER TONIGHT
THROUGH MUCH OF THURSDAY. UPPER AIR ANALYSIS AND WATER VAPOR
IMAGERY SHOW SOMEWHAT OF A SPLIT FLOW PATTERN WITH TWO SEPARATE
UPPER LEVEL SHORTWAVE TROUGHS OVER THE NORTHERN ROCKIES AND OVER
SOUTHERN CALIFORNIA AND NORTHERN BAJA. OVER THE NEXT 24 TO 36
HOURS, THE NORTHERN SHORTWAVE WILL MOVE OUT INTO THE NORTHERN AND
CENTRAL PLAINS WHILE THE SOUTHERN SHORTWAVE MOVES SLOWLY INTO THE
DESERT SOUTHWEST.
LATER TONIGHT AND THURSDAY, THE RIGHT ENTRANCE REGION OF A JET
EXTENDING FROM SOUTH DAKOTA INTO THE GREAT LAKES REGION AND THE
LEFT EXIT REGION OF ANOTHER UPPER JET MOVING UP FROM THE BIG BEND
REGION OF TEXAS INTO OKLAHOMA WILL SET UP OVER SOUTHWEST KANSAS.
MOIST LOW TO MID LEVEL ISENTROPIC LIFT WILL INCREASE LATE TONIGHT
AND CONTINUE INTO THURSDAY ACROSS WESTERN KANSAS INTO THE PANHANDLES
OF OKLAHOMA AND TEXAS. MODEL QPF FIELDS SHOW PRECIPITATION DEVELOPING
TOWARD THURSDAY MORNING ACROSS FAR SOUTHWEST KANSAS WITH ADDITIONAL
PRECIPITATION POSSIBLE TOWARD SOUTH CENTRAL KANSAS. AS THE SHORTWAVE
TROUGH MOVES OUT DURING THE DAY, THE MAIN AREA OF PRECIPITATION
WILL SHIFT EAST. PRECIPITATION AMOUNTS AROUND A HALF TO THREE
QUARTERS OF AN INCH WILL BE POSSIBLE ACROSS MUCH OF SOUTHWEST
KANSAS WITH AMOUNTS UP TO OR OVER AN INCH POSSIBLE IN THE SOUTHERN
FEW TIERS OF COUNTIES. WILL KEEP FAIRLY HIGH POPS UP ALONG I-70 AS
WELL BUT PRECIPITATION AMOUNTS THERE WILL BE CONSIDERABLY LESS.
PRECIPITATION WILL BE WINDING DOWN FAIRLY RAPIDLY FROM WEST TO
EAST DURING THE AFTERNOON HOURS AS THE UPPER WAVE MOVES THROUGH.
HAVE CONTINUED THE TREND OF GOING ABOVE THE LATEST MOS GUIDANCE
FOR OVERNIGHT LOWS GIVEN THE EXPECTED CLOUD COVER. THURSDAY SHOULD
ALSO BE A LITTLE COOLER THAN THE WHAT THE GUIDANCE PORTRAYS.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 309 PM CDT WED MAR 18 2015
BASED ON THE GFS AND ECMWF, A PROGRESSIVE MID LEVEL UPPER FLOW WILL
PERSIST THROUGH THE MEDIUM RANGE PERIOD. INITIALLY, MUCH DRIER
BOUNDARY LAYER AIR WILL MOVE INTO WESTERN KANSAS BEHIND THE EXITING
SYSTEM THURSDAY NIGHT AND THROUGH THE DAY ON FRIDAY INTO SATURDAY.
DOWNS SLOPE SURFACE WINDS AND DRY AIR SHOULD RESULT IN THE WARMEST
TEMPERATURES FRIDAY EXTENDING ACROSS NORTHWEST KANSAS AND THROUGH
THE I-70 CORRIDOR AT LOCATIONS LIKE NESS CITY AND HAYS. SLIGHTLY
LESS WARM TEMPERATURES ARE LIKELY FARTHER SOUTH TO THE OKLAHOMA
LINE, BUT MID 60S`S ARE STILL LIKELY.
MODEL MESOSCALE DIFFERENCE SHOW UP SATURDAY, AS THE MODELS BRING
ANOTHER WEAKENING UPPER LOW ACROSS THE SOUTHERN ROCKIES. THE GFS
SEEMS MORE AGGRESSIVE WITH MOISTURE RETURN ACROSS SW KANSAS AND
PRODUCES RAINFALL IN THE ISENTROPIC REGION AHEAD IF THE SE COLORADO
SURFACE LOW, WHEREAS THE ECMWF DOES NOT, BUT INCREASES CLOUD COVER.
MESOSCALE DETAILS CONCERNING THE POTENTIAL FOR PRECIPITATION IN THE
LATTER PARTS OF THE WEEKEND TO EARLY NEXT WEEK AGAIN LEAVE VERY
LARGE UNCERTAINTY. WITH A WARMER BOUNDARY LAYER DURING THE DAY THE
POSSIBILITY OF MORE UNSTABLE CONDITIONS EXIST WITH ANY FORCING
(WHICH COULD PROMOTE CONVECTION). THE MODELS SUGGEST BROAD WARM
ADVECTION FORCING AFTER SUNDAY HOWEVER DIFFERENCES ARE LARGE AS THE
GFS INDICATES BROAD LIFT ACROSS THE CENTRAL PLAINS AND THE ECMWF
SPLITS THE ENERGY MORE WITH BETTER LIFT TOO FAR NORTH.&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 608 PM CDT WED MAR 18 2015
A FAIRLY DIFFICULT FORECAST TONIGHT INTO TOMORROW WITH A BIT OF
UNCERTAINTY IN HOW WIDESPREAD IFR/LIFR CONDITIONS WILL DEVELOP IN
THE 06Z TO 15Z TIME FRAME. LOW PRESSURE WILL CONTINUE TO SLOWLY
DEVELOP ACROSS SOUTHEAST COLORADO AND ADJACENT FAR NORTHEAST NEW
MEXICO TONIGHT. THE LOW LEVEL WIND FIELD WILL BE OUT OF THE EAST-
SOUTHEAST, WHICH WILL ALLOW HIGHER DEWPOINT AIR (IN THE UPPER 30S
TO LOWER 40S) TO EXPAND WEST THROUGH THE NIGHT. THE OFFICIAL
FORECAST WILL FOLLOW THE TREND OF THE RAP13 AND HRRR MODELS, WHICH
DEPICT FOG DEVELOPING IN THE BEST ZONE OF MOIST ADVECTION IN THE
09-15Z TIME FRAME, WHICH WOULD INCLUDE DDC AND GCK. LIGHT RAIN
WILL ALSO AFFECT THESE TERMINALS FROM ROUGHLY MID-MORNING THROUGH
MID TO LATE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 41 48 36 68 / 80 90 20 0
GCK 39 50 34 67 / 80 90 10 0
EHA 39 49 38 65 / 80 90 20 0
LBL 41 50 37 65 / 80 90 30 10
HYS 38 55 33 72 / 50 70 0 0
P28 43 49 38 69 / 70 90 40 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GERARD
LONG TERM...RUSSELL
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS GOODLAND KS
253 PM MDT TUE MAR 17 2015
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 253 PM MDT TUE MAR 17 2015
WV IMAGERY AND RAP H5 ANALYSIS SHOWS CUTOFF LOW OVER MEXICO WITH
RIDGE EXPECTING ACROSS THE SOUTHER MISSISSIPPI VALLEY INTO THE
SOUTHERN PLAINS. WEST-NORTHWEST FLOW IN IN PLACE ACROSS THE CWA. AT
THE SURFACE HIGH PRESSURE CENTERED OVER SOUTH DAKOTA EXTENDING
SOUTH ACROSS NEBRASKA TO THE COLORADO STATE LINE.
THIS AFTERNOON...VERY LOW TD VALUES HAVE MIXED TO THE SURFACE AND
ADVECTED WEST INTO OUR CWA...WITH NEGATIVE VALUES IN OUR NORTHEAST.
AS TEMPS HAVE SLOWLY MODERATED INTO THE THE LOWER 50S THIS AFTERNOON
RH VALUES HAVE DROPPED BELOW 15 PERCENT. GRADIENT REMAINS
RELATIVELY WEAK WITH CWA UNDER THE INFLUENCE OF SURFACE HIGH
PRESSURE...AND WHILE A FEW GUSTS TO 20KT HAVE OCCURRED PREVAILING
WINDS REMAIN AROUND 10-15 MPH. DECIDED AGAINST ISSUANCE OF RED FLAG
WARNING DUE TO WINDS.
TONIGHT...COOL AIR MASS AND LOW LEVEL DRY AIR REMAIN IN PLACE
THROUGH TONIGHT. WHILE GUIDANCE IS HINTING AT MID-HIGH CLOUDS
LINGERING OVERNIGHT...LOCATIONS THAT SEE PRIMARILY CLEAR CONDITIONS
COULD DROP TO THE UPPER TEENS. MOST GUIDANCE KEEPS LOWS IN THE UPPER
20S/LOWER 30S.
WEDNESDAY...LEE TROUGH BEGINS TO DEVELOP TOWARD THE COLORADO STATE
LINE IN RESPONSE TO APPROACHING TROUGH IN THE NORTHERN ROCKIES. FLOW
ALOFT REMAINS OUT OF THE WEST. CONDITIONS SHOULD REMAIN DRY WITH
ONLY CLOUD COVER. THIS COULD COMPLICATE TEMP FORECAST/DAYTIME MIXING.
INCREASING WAA OVER THE CWA SHOULD SUPPORT TEMP RECOVERY INTO THE
60S FOR MOST LOCATIONS...POSSIBLY NEAR 70F IN THE WEST IF THERE
IS BETTER CLEARING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 253 PM MDT TUE MAR 17 2015
DURING THE EXTENDED FORECAST PERIOD...THERE ARE A COUPLE
OPPORTUNITIES FOR BENEFICIAL PRECIPITATION AS DISTURBANCES MOVE
THROUGH. THE FIRST OPPORTUNITY ARRIVES WEDNESDAY NIGHT INTO
THURSDAY. A STRONG SHORTWAVE TROUGH...CURRENTLY JUST OFF THE PACIFIC
COAST...IS EXPECTED TO MAKE LANDFALL...MOVE EAST OVER IDAHO AND
MONTANA BEFORE DIVING SOUTH OVER THE HIGH PLAINS THURSDAY.
PRECIPITATION SHOULD DEVELOP ALONG THE COLORADO FRONT RANGE AND
MEANDER TOWARDS THE TRI-STATE REGION EARLY THURSDAY MORNING.
PRECIPITATION PERSISTS THROUGHOUT THE DAY BEFORE A COLD FRONT FORCES
SHOWERS SOUTH. SCATTERED SHOWERS SEEM LIKELY...HOWEVER...PERSISTENT
FRONTOGENESIS INDICATE A BAND OF MODERATE RAIN IS POSSIBLE SOUTH OF
INTERSTATE 70. HAVE FORECAST HIGHEST PRECIP AMOUNTS AND POPS FOR
THESE LOCATIONS. GLANCING AT FORECAST SOUNDINGS...DO NOT ANTICIPATE
ANY MIXED PRECIPITATION OR A COMPLETE CHANGE TO SNOW. DENSE CLOUD
COVER WITHOUT A SIGNIFICANT AIRMASS CHANGE WOULD INDICATE
TEMPERATURES ABOVE FREEZING DUE TO LACK OF DIURNAL COOLING.
THE NEXT CHANCE FOR PRECIPITATION ARRIVES SUNDAY WITH ANOTHER
NORTHWEST SHORTWAVE ARRIVING. UNFORTUNATELY...GUIDANCE HAS SOME
DIFFERENCES THAT LOWER CONFIDENCE FOR THIS FORECAST RUN. GEFS
ENSEMBLES INDICATE A LARGE AMOUNT OF SPREAD WITHIN ITS ENSEMBLE
MEMBERS. THE GEFS ENSEMBLE MEAN GIVES SOME CREDENCE TO THE CANADIAN
AND EUROPEAN SOLUTIONS WHILE THE GFS REMAINS AN OUTLIER. THE GFS
INDICATES A VERY SIMILAR SOLUTION TO THE EUROPEAN/CANADIAN MODELS
BUT IS DISPLACED NORTH BY SEVERAL HUNDRED MILES. GUIDANCE DOESN`T
SEEM TO BE HANDLING GULF RETURN FLOW WELL AS THERE ARE LARGE
DIFFERENCES IN DEWPOINT FIELDS. FEEL THERE SHOULD BE ENOUGH GULF
MOISTURE FETCH TO BRING SOME HIGHER DEWPOINTS AND THUS INSTABILITY
INTO THE REGION. THEREFORE...WE MAY OBSERVE A FEW THUNDERSTORMS WITH
THIS SYSTEM. HAVE NOT MENTIONED THUNDER YET AS TEMPORAL AND SPACIAL
DETAILS NEED TO BE RESOLVED. ON THE BACK SIDE...THERE COULD BE A
CHANGE TO SNOW. HOWEVER...DIFFERENCES ALSO REMAIN ON TEMPERATURES
AND COLD FRONT ARRIVAL TIMING SO DON`T FEEL CONFIDENT TO MENTION ANY
AMOUNTS.
AS FOR FIRE WEATHER...LOW RELATIVE HUMIDITY TO 20 PERCENT IS ONCE
AGAIN EXPECTED FRIDAY AND SATURDAY AS TEMPERATURES WARM ACROSS THE
REGION. HOWEVER...STRONG WINDS ARE CURRENTLY NOT EXPECTED. WITH
RECENT FIRE GROWTH DUE TO LOW RELATIVE HUMIDITY AND SUSCEPTIBLE
FUELS...ELEVATED FIRE DANGER MAY DEVELOP FOR PORTIONS OF THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1128 AM MDT TUE MAR 17 2015
VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF PERIOD AT BOTH GLD
AND KMCK TERMINALS. WINDS WILL SHIFT FROM THE EAST TO SOUTHEAST
THROUGH THE TAF PERIOD AS SURFACE HIGH PRESSURE MOVE OUT OF THE
NORTHERN PLAINS AND SURFACE LOW PRESSURE DEVELOPS OVER EASTERN
COLORADO. WINDS SHOULD GENERALLY REMAIN BELOW 12KT THROUGH
TONIGHT...THOUGH THERE COULD BE OCCASIONAL GUSTS AROUND 18KT
THROUGH THIS EVENING. WINDS WILL BEGIN TO INCREASE ALONG THE KS/CO
BORDER WITH SURFACE LOW DEVELOPMENT AROUND SUNRISE
WEDNESDAY...PRIMARILY IMPACTING KGLD DURING THIS TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...RRH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS TOPEKA KS
639 AM CDT Tue Mar 17 2015
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 321 AM CDT TUE MAR 17 2015
Today, strong low-level CAA will cause a surface ridge of high
pressure across SD early this morning to expand southeast across the
central plains into northeast KS and northern MO. The pressure
gradient between the surface ridge across the northern plains and an
area low pressure across southern OK has caused north-northeast
winds to range from 15 to 25 MPH with some gusts to around 45 MPH,
especially across north central KS. The stronger winds will continue
this morning but should gradually diminish under 20 MPH during the
late afternoon hours as the surface ridge builds southeast across
the central plains into the mid MS river valley. Highs Today will be
cooler with lower to mid 50s across the northern counties and mid to
upper 50s across the southern counties.
Tonight, a closed upper low across southwest TX will fill into an
open wave and lift northeast into southwest OK by 12Z WED. As the
surface ridge of high pressure shifts east into the Great Lakes
states, southerly winds at 850mb will begin to advect richer
moisture northward across OK. After 6Z the isentropic lift across
east central KS will increase. All the model forecast soundings show
a dry layer between the surface and 875mb, which must saturate
before any measurable precip moves north into the southern counties
of the CWA. At this time I kept most of the CWA dry with a small
sliver across southern Coffey and Anderson county for a slight
chance for showers or sprinkles towards 12Z WED. Overnight lows will
range from around 30 degrees along the NE border where skies will be
clear for most of the night, to the upper 30s across the southeast
counties. After 300 AM temperatures across east central KS may
remain steady or slowly rise as weak WAA develops.
.LONG TERM...(Wednesday through Monday)
Issued at 321 AM CDT TUE MAR 17 2015
By Wednesday morning, models are in good agreement with showing a
mid-level shortwave trough centered over the Texas panhandle and
shifting east northeastward through Wednesday night. While the main
wave should remain just south of the forecast area, models continue
to show a chance for light rain extending northward over the
southeastern half of the forecast area as isentropic lift increases.
These light rain showers should diminish from west to east Wednesday
night before the next approaching shortwave trough moves into the
Northern Plains and extends into the Central Plains on Thursday.
This second wave may bring another chance for a few passing rain
showers Thursday into Thursday evening across the southern half of
the forecast area. However, models are still uncertain with the
precipitation chances over the forecast area as they continue to
show the better chances being focused west and south of the forecast
area. With mostly cloudy skies in place from these two passing
waves, expect temperatures Wednesday and Thursday to be near or
slightly below the seasonal normals with highs in the upper 40s to
upper 50s and lows in the 30s.
Expect dry conditions Friday into Sunday as surface high pressure
advances into the area behind the exiting shortwave trough. Have
trended a few degrees warmer for temperatures with highs reaching
into the upper 60s/low 70s. By Saturday, models show a mid-level
trough advancing into the Pacific Northwest, moving over the Rockies
on Sunday, and potentially developing a weak embedded shortwave just
ahead of the main trough. This advancing trough will help to push an
area of low pressure from the Rockies southeastward into Oklahoma
and Texas with a weak boundary potentially extending northward
toward the area. The GFS is much more aggressive with the potential
for precipitation across the forecast area Sunday night into Monday,
while the ECMWF keeps the precipitation primarily focused to the
south and west. Due to this model uncertainty, only have slight to
low-end chance PoPs in for Sunday night through Monday night.
Temperatures should drop back down near the seasonal normals for
Sunday with highs in the mid 50s to low 60s and slightly cooler
still for Monday with highs in the low/mid 50s.
&&
.FIRE WEATHER...
Issued at 321 AM CDT TUE MAR 17 2015
Most of the area will be under a very high fire danger today. The
mixing depth of the boundary layer this afternoon will increase to
875mb-900mb during the afternoon hours. Most areas will see minimum
RH`s drop to 25 to 30 percent during the afternoon. The northern and
western counties of the CWA will see RH`s drop to 20 to 25 percent
with some areas dipping as low as 18 percent. I used the advance
research WRF model to populate dewpoints. The RAP model looked too
low for dewpoints this afternoon but if other mesoscale models begin
to converge towards the RUC solutions, then dewpoints and RH`s will
have to be adjusted downward. The sustained winds should drop below
20 MPH and gusts less than 25 MPH through he afternoon hours across
the north and western counties of the CWA, thus red flag criteria
should not be met. However, the low RH and dry fuels combined with
winds just under red flag criteria will cause any control burns to
become out of controlled wild fires. Once again all schedule burning
today should be postponed.
&&
.AVIATION...(For the 12Z TAFs through 12Z Wednesday Morning)
Issued at 623 AM CDT TUE MAR 17 2015
A brief period of broken stratus with MVFR ceilings will shift
south of the terminals by 12Z. Another patch of MVFR stratus near
KMCI will head south-southwest and remain east of KFOE and KTOP
through 15Z. North-northeast winds will increase by 15Z to 15 to
17 KTS with gusts of 25 to 27 KTS. The winds will diminish by 21Z
to 10 to 12 KTS. High and mid clouds will increase Tonight, and by
12Z WED there could be broken ceilings of VFR stratus.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...Hennecke
FIRE WEATHER...Gargan
AVIATION...Gargan
AREA FORECAST DISCUSSION
NWS TOPEKA KS
324 AM CDT Tue Mar 17 2015
.SHORT TERM...(Today and Tonight)
Issued at 321 AM CDT TUE MAR 17 2015
Today, strong low-level CAA will cause a surface ridge of high
pressure across SD early this morning to expand southeast across the
central plains into northeast KS and northern MO. The pressure
gradient between the surface ridge across the northern plains and an
area low pressure across southern OK has caused north-northeast
winds to range from 15 to 25 MPH with some gusts to around 45 MPH,
especially across north central KS. The stronger winds will continue
this morning but should gradually diminish under 20 MPH during the
late afternoon hours as the surface ridge builds southeast across
the central plains into the mid MS river valley. Highs Today will be
cooler with lower to mid 50s across the northern counties and mid to
upper 50s across the southern counties.
Tonight, a closed upper low across southwest TX will fill into an
open wave and lift northeast into southwest OK by 12Z WED. As the
surface ridge of high pressure shifts east into the Great Lakes
states, southerly winds at 850mb will begin to advect richer
moisture northward across OK. After 6Z the isentropic lift across
east central KS will increase. All the model forecast soundings show
a dry layer between the surface and 875mb, which must saturate
before any measurable precip moves north into the southern counties
of the CWA. At this time I kept most of the CWA dry with a small
sliver across southern Coffey and Anderson county for a slight
chance for showers or sprinkles towards 12Z WED. Overnight lows will
range from around 30 degrees along the NE border where skies will be
clear for most of the night, to the upper 30s across the southeast
counties. After 300 AM temperatures across east central KS may
remain steady or slowly rise as weak WAA develops.
.LONG TERM...(Wednesday through Monday)
Issued at 321 AM CDT TUE MAR 17 2015
By Wednesday morning, models are in good agreement with showing a
mid-level shortwave trough centered over the Texas panhandle and
shifting east northeastward through Wednesday night. While the main
wave should remain just south of the forecast area, models continue
to show a chance for light rain extending northward over the
southeastern half of the forecast area as isentropic lift increases.
These light rain showers should diminish from west to east Wednesday
night before the next approaching shortwave trough moves into the
Northern Plains and extends into the Central Plains on Thursday.
This second wave may bring another chance for a few passing rain
showers Thursday into Thursday evening across the southern half of
the forecast area. However, models are still uncertain with the
precipitation chances over the forecast area as they continue to
show the better chances being focused west and south of the forecast
area. With mostly cloudy skies in place from these two passing
waves, expect temperatures Wednesday and Thursday to be near or
slightly below the seasonal normals with highs in the upper 40s to
upper 50s and lows in the 30s.
Expect dry conditions Friday into Sunday as surface high pressure
advances into the area behind the exiting shortwave trough. Have
trended a few degrees warmer for temperatures with highs reaching
into the upper 60s/low 70s. By Saturday, models show a mid-level
trough advancing into the Pacific Northwest, moving over the Rockies
on Sunday, and potentially developing a weak embedded shortwave just
ahead of the main trough. This advancing trough will help to push an
area of low pressure from the Rockies southeastward into Oklahoma
and Texas with a weak boundary potentially extending northward
toward the area. The GFS is much more aggressive with the potential
for precipitation across the forecast area Sunday night into Monday,
while the ECMWF keeps the precipitation primarily focused to the
south and west. Due to this model uncertainty, only have slight to
low-end chance PoPs in for Sunday night through Monday night.
Temperatures should drop back down near the seasonal normals for
Sunday with highs in the mid 50s to low 60s and slightly cooler
still for Monday with highs in the low/mid 50s.
&&
.AVIATION...(For the 06Z TAFs through 06Z Tuesday Night)
Issued at 1122 PM CDT MON MAR 16 2015
Strong cold front will sweep through the area with gusty northeast
winds expected through at least 21z Tuesday. There will be a
narrow axis of moisture and associated stratocumulus cloud that
also move through the area between 06z and 12z. At this point
based off of satellite...obs and fcst soundings it does not
appear to be sufficient to warrant tempo or prevailing MVFR CIGS
and will continue to carry VFR through the fcst.
&&
.FIRE WEATHER...
Issued at 321 AM CDT TUE MAR 17 2015
Most of the area will be under a very high fire danger today. The
mixing depth of the boundary layer this afternoon will increase to
875mb-900mb during the afternoon hours. Most areas will see minimum
RH`s drop to 25 to 30 percent during the afternoon. The northern and
western counties of the CWA will see RH`s drop to 20 to 25 percent
with some areas dipping as low as 18 percent. I used the advance
research WRF model to populate dewpoints. The RAP model looked too
low for dewpoints this afternoon but if other mesoscale models begin
to converge towards the RUC solutions, then dewpoints and RH`s will
have to be adjusted downward. The sustained winds should drop below
20 MPH and gusts less than 25 MPH through he afternoon hours across
the north and western counties of the CWA, thus red flag criteria
should not be met. However, the low RH and dry fuels combined with
winds just under red flag criteria will cause any control burns to
become out of controlled wild fires. Once again all schedule burning
today should be postponed.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gargan
LONG TERM...Hennecke
AVIATION...Omitt
FIRE WEATHER...Gargan
AREA FORECAST DISCUSSION...UPDATED
NWS TOPEKA KS
1132 PM CDT Mon Mar 16 2015
...Update to aviation forecast discussion...
.SHORT TERM...(This Evening through Tuesday)
Issued at 324 PM CDT MON MAR 16 2015
Latest satellite water vapor loop shows southern stream upper low
spinning over Baja while a northern stream trough moves across the
Canadian Prairies. An upper level ridge extends from the gulf coast
into Nebraska. A surface cold front stretched from southern
Minnesota to near Scotts Bluff Nebraska at 19Z. Dew points have
dropped into the 20s and lower 30s this afternoon with relative
humidity ranging from around 10 percent in north central Kansas to
the teens across much of northeast and east central Kansas. Expect
extreme fire danger to continue into the early evening hours as
currently forecast. Once again the RAP has been the best performer
with regards to dew points and have used into the mid evening hours.
Tonight the cold front will move south into north central Kansas
this evening, then proceed south across the rest of the area through
the night. Winds will be gusty from the north with sustained speeds
around 20 mph with gusts to around 35 mph with a tight pressure
gradient present behind the front. Lows tonight will cool into the
upper 30s to mid 40s. As the surface high moves east and south
through the day on Tuesday gusty northeast winds will be on the
decrease in the afternoon hours as the pressure gradient relaxes.
Cold advection Tuesday will lead to highs around normal for mid
March with readings in the mid to upper 50s.
.LONG TERM...(Tuesday Night through Monday)
Issued at 324 PM CDT MON MAR 16 2015
.Tuesday Night thru Thursday...
The remnants of the cutoff low in the TX Big Bend will begin to
eject northeastward into the south central plains Tuesday night. As
it does...moisture/warm air advection will spread northeastward into
the cwa with increasing chances of rain late in the night into
Wednesday. Lows Tuesday night should be in the middle to upper 30s
across the south.
Models are in fair agreement on keeping pops mainly across the
southeast half of the county warning area during the day Wednesday
before the shortwave trough passes off to the east and southeast of
the cwa Wednesday night. Will only leave a slight chance for rain in
the far southeast corner. Lows will be in the middle to upper 30s.
On Thursday boundary stalls to the south of the cwa...however the
next upstream shortwave trough will be approaching through the day
and have left a slight chance for rain across the southeast half of
the cwa as the NAM and GEM models still develop some rain north of
the front...although the GFS and EC are drier with precip further
south. Highs Thursday with the clouds...northeast winds and precip
chances should be limited to the middle to upper 50s.
.Thursday Night thru Monday...
By Friday afternoon, a split flow pattern begins to set up with a
cut off low situated over the Baja Peninsula and a northern stream
ridge axis over Idaho. This southern system will continue to move
west throughout Saturday, and will allow warm air advection to take
place due to a strong upper level jet streaming in warmer air from
the southwest. A north/south thermal axis on Saturday sets up
highs in the mid 60s to the north transitioning to the lower 70s
to the south.
Highs Sunday will be cooler as a colder airmass to the north skims
the Kansas/Nebraska boarder. After Sunday, models tend to disagree with
how to handle the next wave moving out of the Rockies. As of now,
have a slight chance for precipitation Monday, but this could
change with future model runs.
&&
.AVIATION...(For the 06Z TAFs through 06Z Tuesday Night)
Issued at 1122 PM CDT MON MAR 16 2015
Strong cold front will sweep through the area with gusty northeast
winds expected through at least 21z Tuesday. There will be a
narrow axis of moisture and associated stratocumulus cloud that
also move through the area between 06z and 12z. At this point
based off of satellite...obs and fcst soundings it does not
appear to be sufficient to warrant tempo or prevailing MVFR CIGS
and will continue to carry VFR through the fcst.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...53
LONG TERM...Heller/63
AVIATION...Omitt
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
428 PM EDT TUE MAR 17 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 417 PM EDT TUE MAR 17 2015
WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW
THROUGH THE NORTHERN GREAT LAKES BETWEEN A DEEP TROUGH OVER HUDSON
BAY AND A RIDGE FROM THE WRN PLAINS INTO WRN CANADA. WITH THE
CONFLUDENT MID/UPPER LEVEL FLOW...QVECTOR DIV AND SUBSIDENCE
PREVAILED OVER THE REGION. AT THE SFC...STRONG NW GRADIENT FLOW
PREVAILED AHEAD OF A 1035 MB HIGH OVER THE NRN PLAINS. DAYTIME
HEATING/MIXING IN THE DEEPENING BNDRY LAYER HAS RESULTED IN WIND
GUSTS INTO THE 30 TO 35 MPH RANGE. WITH DEWPOINTS IN THE 0 TO 10F
RANGE...ONLY HIGH BASED CU HAD DEVELOPED. AN OPEN PATCH OF WATER
OVER SRN LAKE SUPERIOR HAS ALLOWED SOME LAKE EFFECT CLOUDS/FLURRIES
TO DEVELOP FROM P53 EASTWARD.
TONIGHT...850 MB TEMPS REMAINING AROUND -14C OVERNIGHT WILL PROVIDE
ONLY MARGINAL INSTABILITY FOR ANY LES IN THE DRY AIRMASS BUT SHOULD
BE ENOUGH TO SUPPORT CONTINUED NW FLOW CLOUDS/FLURRIES INTO THE ERN
CWA. OTHERWISE...THE GUSTY WINDS WILL DIMINISH THIS EVENING WITH THE
LOSS OF DAYTIME HEATING. ALTHOUGH WINDS WILL DECOUPLE AS HIGH PRES
BUILDS INTO THE AREA...THERE SHOULD BE ENOUGH MIXING TO KEEP TEMPS
FROM DROPPING OFF TOO FAR WITH MIN READINGS MAINLY IN THE TEENS
INLAND TO AROUND 20 ALONG THE LAKE.
WED...FCST SOUNDINGS SUGGEST THAT ONLY A FEW HIGH CLOUDS WILL
PREVAIL. OTHERWISE...WITH LIGHTER WINDS...AND 850 MB TEMPS IN THE -
8C TO -12C RANGE HIGHS WILL CLIMB INTO THE LOWER 30S EAST TO THE LOW
40S SOUTH AND WEST.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 428 PM EDT TUE MAR 17 2015
COOL WITH LIMITED PRECIP THROUGH THE LONG TERM PERIOD.
NW FLOW ALOFT...AS BEEN THE CASE SO FREQUENTLY THIS YEAR...WILL BE
SET UP AT 00Z THURSDAY...AS 2 500MB LOWS REMAIN TO OUR N /OVER
HUDSON BAY AND JUST OFF THE COAST OF NEWFOUNDLAND/. OTHERWISE...THE
LATEST SFC HIGH OVER LAKE SUPERIOR DOWN THROUGH LOWER MI WILL BE ON
THE WAY OUT...SHIFTING ACROSS LAKE HURON AND LAKE ERIE BY DAYBREAK
THURSDAY. LIGHT S WINDS WILL BE ON THE BACK SIDE OF THE LOW FOR
THURSDAY AFTERNOON. HIGH TEMPS WILL JUMP UP 2-5F FROM WEDNESDAY
AFTERNOON...GENERALLY 40-46F.
ALSO THURSDAY...THE SFC LOW OVER S CENTRAL CANADA AND THE N PLAINS
STATES WILL MOVE ACROSS CENTRAL ONTARIO THURSDAY EVENING...AND W
QUEBEC ON FRIDAY. THIS WILL ALLOW A COLD FRONT TO SLOWLY SINK ACROSS
LAKE SUPERIOR AND UPPER MI ON FRIDAY. THE 500MB NEWFOUNDLAND LOW
WILL EXIT N...WHILE THE HUDSON BAY LOW DIGS S ACROSS ONTARIO FRIDAY
NIGHT/SATURDAY...USHERING IN MUCH COLDER AIR AND WINTER-LIKE
WEATHER. SFC TEMPS SATURDAY MAY ONLY TOP OUT IN THE UPPER TEENS TO
UPPER 20S...NEARING 30F SOUTH CENTRAL...AS THE COLD FRONT SINKS
ACROSS THE LOWER GREAT LAKES AND CANADIAN HIGH PRESSURE BUILDS INTO
THE UPPER GREAT LAKES.
EXPECT THE 500MB LOW TO EXIT INTO QUEBEC SUNDAY MORNING. THIS WILL
RESULT IN THE EXIT OF THE WINTER-LIKE WEATHER AS HIGH PRESSURE
SETTLES IN ALOFT AND AT THE SFC THROUGH MONDAY EVENING. THE SFC HIGH
WILL THEN DRIFT E TO THE LOWER GREAT LAKES TO MID ATLANTIC ON
TUESDAY. LOOK FOR SLOWLY MODERATING TEMPERATURES FOR THE START OF
THE NEXT WORK WEEK. NORMAL HIGH TEMPS THIS TIME OF YEAR ARE
TYPICALLY IN THE MID TO UPPER 30S. LOOKS LIKE AFTER FRIDAY...WE WILL
GET BACK TO THESE NORMAL HIGH TEMP VALUES BY NEXT TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 351 PM EDT TUE MAR 17 2015
DRY AIR MASS WILL RESULT IN VFR CONDITIONS AT KIWD/KCMX/KSAW THROUGH
THE FCST PERIOD. EXPECT GUSTY WNW/NW WINDS AT ALL TERMINALS THIS
AFTERNOON UNDER DEEPENING MIXED LAYER (GUSTS TO 25-30KT WILL BE
COMMON). WINDS WILL DIMINISH AROUND SUNSET.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 417 PM EDT TUE MAR 17 2015
NW WINDS WILL CONTINUE UP TO 30 KTS TODAY UNDER A TIGHT PRESSURE
GRADIENT. WILL MENTION A FEW GALE FORCE GUSTS OVER THE EAST INTO
THIS EVENING. WINDS WILL DIMINISH TONIGHT AND THEN RUN UNDER 25 KTS
THE REST OF THE WEEK. OPEN WATER REMAINS THE MOST PREVALENT OVER
WESTERN LK SUPERIOR AND OVER SCNTRL LK SUPERIOR TO THE EAST OF THE
KEWEENAW PENINSULA. EXPECT THE ICE COVER OVER THE REST OF THE LAKE
TO SLOWLY DIMINISH THE REST OF THIS WEEK DUE TO SHIFTING WINDS AND
AS DAYTIME TEMPERATURES MOST DAYS RISE ABOVE FREEZING...ESPECIALLY
OVER THE WESTERN HALF OF LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
418 PM EDT TUE MAR 17 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 417 PM EDT TUE MAR 17 2015
WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW
THROUGH THE NORTHERN GREAT LAKES BETWEEN A DEEP TROUGH OVER HUDSON
BAY AND A RIDGE FROM THE WRN PLAINS INTO WRN CANADA. WITH THE
CONFLUDENT MID/UPPER LEVEL FLOW...QVECTOR DIV AND SUBSIDENCE
PREVAILED OVER THE REGION. AT THE SFC...STRONG NW GRADIENT FLOW
PREVAILED AHEAD OF A 1035 MB HIGH OVER THE NRN PLAINS. DAYTIME
HEATING/MIXING IN THE DEEPENING BNDRY LAYER HAS RESULTED IN WIND
GUSTS INTO THE 30 TO 35 MPH RANGE. WITH DEWPOINTS IN THE 0 TO 10F
RANGE...ONLY HIGH BASED CU HAD DEVELOPED. AN OPEN PATCH OF WATER
OVER SRN LAKE SUPERIOR HAS ALLOWED SOME LAKE EFFECT CLOUDS/FLURRIES
TO DEVELOP FROM P53 EASTWARD.
TONIGHT...850 MB TEMPS REMAINING AROUND -14C OVERNIGHT WILL PROVIDE
ONLY MARGINAL INSTABILITY FOR ANY LES IN THE DRY AIRMASS BUT SHOULD
BE ENOUGH TO SUPPORT CONTINUED NW FLOW CLOUDS/FLURRIES INTO THE ERN
CWA. OTHERWISE...THE GUSTY WINDS WILL DIMINISH THIS EVENING WITH THE
LOSS OF DAYTIME HEATING. ALTHOUGH WINDS WILL DECOUPLE AS HIGH PRES
BUILDS INTO THE AREA...THERE SHOULD BE ENOUGH MIXING TO KEEP TEMPS
FROM DROPPING OFF TOO FAR WITH MIN READINGS MAINLY IN THE TEENS
INLAND TO AROUND 20 ALONG THE LAKE.
WED...FCST SOUNDINGS SUGGEST THAT ONLY A FEW HIGH CLOUDS WILL
PREVAIL. OTHERWISE...WITH LIGHTER WINDS...AND 850 MB TEMPS IN THE -
8C TO -12C RANGE HIGHS WILL CLIMB INTO THE LOWER 30S EAST TO THE LOW
40S SOUTH AND WEST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 446 AM EDT TUE MAR 17 2015
GENERALLY QUIET WEATHER PATTERN CONTINUES INTO THE UPCOMING WEEKEND.
WIDESPREAD PRECIPITATION CHANCES APPEAR ON THE LOW SIDE...THOUGH
JUST A FEW DAYS AGO THAT ALSO APPEARED TO BE THE CASE FOR WHAT
TURNED OUT TO BE A SOGGY MONDAY OVER MUCH OF CWA. DESPITE THE RAIN
ON MONDAY THOUGH...DEFICITS FOR MARCH REMAIN OVER 1 INCH AND YEARLY
DEFICITS ARE NEAR 2.75 INCHES. FOR MOST PART...WE WILL CONTINUE TO
INCREASE THE DEFICITS THROUGH THE EXTENDED PERIOD.
NW FLOW OVER UPR LAKES EARLY THIS WEEK BECOMES MORE WESTERLY BY
THURSDAY...ALLOWING SHORTWAVE EMERGING OUT OF SHARP TROUGH JUST OFF
THE WEST COAST CURRENTLY...TO RIDE OVER THE NORTHERN PLAINS AND
EVENTUALLY TO ADVANCE OVER THE WESTERN GREAT LAKES. GFS AND ECMWF
INDICATE LIGHT QPF ON THURSDAY IN RETURN FLOW WARM AIR ADVECTION
REGIME AS SFC RIDGE MOVES TO THE EAST. INCREASING 925-850MB RH ALONG
WITH SOME WARM AIR ADVECTION AT SAME LEVELS IN ADDITION TO LIFT FM
THE SHORTWAVE SUGGEST AT LEAST SLIGHT CHANCES FOR RAIN SHOWERS
THURSDAY INTO THURSDAY EVENING. COLD FRONT WORKS THROUGH THURSDAY
NIGHT INTO FRIDAY...SO WILL CONTINUE LOW CHANCE POPS AT THAT TIME.
DESPITE PASSAGE OF SFC COLD FRONT...BULK OF COLD AIR LAGS MORE INTO
FRIDAY NIGHT AND SATURDAY WHERE H85 TEMPS BLO -20C ARRIVE. RAISED
TEMPS ON FRIDAY UP OVER CONSENSUS WITH AREAS OVER BARE GROUND OF
SNCTRL CWA POSSIBLY TO 50 DEGREEES. FOR THE WEATHER FRIDAY...TRENDED
AWAY FM THE WETTER GFS AND INSTEAD LEANED ON THE ECMWF/GEM-NH SINCE
THE GFS APPEARED BOTH TOO QUICK AND TOO FAR NORTH WITH SECONDARY
SHORTWAVE MOVING IN ON FRIDAY WHICH ENHANCED ADDITIONAL PRECIP ALONG
THE DEPARTING FRONT. DPROG/DT OF GFS INDICATES THERE IS MINIMAL
CONSISTENCY IN WHAT GFS SHOWS...SO LIKE A MORE TONED DOWN CONSENSUS
FOR POPS.
TURNS COLD FOR THE UPCOMING WEEKEND. TEMPS WILL RUN WELL BLO NORMAL
AS DAYTIME HIGHS SATURDAY WILL STRUGGLE TO REACH LOWER 20S ALONG LK
SUPERIOR AND THE FREEZING MARK OVER THE SCNTRL. NORMAL HIGHS ALONG LK
SUPERIOR MID-UPR 30S. A BIT BETTER ON SUNDAY WITH UPR 20S TO MID 30S
OVER THE CWA. NIGHTTIME LOWS SINGLE DIGITS OR TEENS ABOVE ZERO.
LOWERED MINS ON SUNDAY NIGHT COMPARED TO CONSENSUS ESPECIALLY INLAND.
GIVEN SFC RIDGE OVERHEAD AND COLD AIRMASS...THINK THERE IS AT LEAST
SMALL OPPORTUNITY FOR SOME SUB ZERO LOW TEMPS. RECORD LOW TEMPS AT
NWS MARQUETTE CAN BE BLO ZERO THROUGH MID APRIL...SO NOT A STRETCH
THAT WE COULD SEE MINS TEMPS THAT LOW ON SUNDAY NIGHT. NW WINDS AND
SUCH COLD TEMPS THROUGH THE WEEKEND ALONG WITH A FORECAST OF HIGHER
RH AT 925/850/700MB SUGGEST THERE MAY BE LAKE EFFECT FOR AREAS
FAVORED BY NW FLOW FRIDAY NIGHT THROUGH MOST OF THE WEEKEND. ICE
COVER STILL PRETTY WIDESPREAD OVER THE EASTERN LAKE...SO KEPT POPS
ONLY LOW CHANCE.
TEMPS MODERATE SLIGHTLY JUST BEYOND EXTENDED TIME FRAME...BUT NO
SIGNIFICANT OR LARGE SCALE WARMUP APPEARS TO BE IN THE OFFING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 351 PM EDT TUE MAR 17 2015
DRY AIR MASS WILL RESULT IN VFR CONDITIONS AT KIWD/KCMX/KSAW THROUGH
THE FCST PERIOD. EXPECT GUSTY WNW/NW WINDS AT ALL TERMINALS THIS
AFTERNOON UNDER DEEPENING MIXED LAYER (GUSTS TO 25-30KT WILL BE
COMMON). WINDS WILL DIMINISH AROUND SUNSET.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 417 PM EDT TUE MAR 17 2015
NW WINDS WILL CONTINUE UP TO 30 KTS TODAY UNDER A TIGHT PRESSURE
GRADIENT. WILL MENTION A FEW GALE FORCE GUSTS OVER THE EAST INTO
THIS EVENING. WINDS WILL DIMINISH TONIGHT AND THEN RUN UNDER 25 KTS
THE REST OF THE WEEK. OPEN WATER REMAINS THE MOST PREVALENT OVER
WESTERN LK SUPERIOR AND OVER SCNTRL LK SUPERIOR TO THE EAST OF THE
KEWEENAW PENINSULA. EXPECT THE ICE COVER OVER THE REST OF THE LAKE
TO SLOWLY DIMINISH THE REST OF THIS WEEK DUE TO SHIFTING WINDS AND
AS DAYTIME TEMPERATURES MOST DAYS RISE ABOVE FREEZING...ESPECIALLY
OVER THE WESTERN HALF OF LAKE SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
113 AM EDT TUE MAR 17 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 404 PM EDT MON MAR 16 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A FAST W-E FLOW
ALOFT EXTENDING FM THE NRN PLAINS INTO THE UPR GREAT LKS BTWN UPR
RDG OVER THE SRN PLAINS AND A CLOSED H5 LO MOVING INTO HUDSON BAY. A
PAIR OF SHRTWVS EMBEDDED IN THIS ZONAL FLOW AND IN THE RRQ OF 160KT
H3 JET MAX WITHIN THE CONFLUENT FLOW ALONG WITH SOME MID LVL FGEN IS
GENERATING A BAND OF LIGHT RA STRETCHING FM NRN MN THRU UPR MI
DESPITE THE PRESENCE OF SOME VERY DRY LLVL AIR SHOWN ON THE 12Z
INL/MPX/GRB RAOBS. DRYING ALF AND IN THE WAKE OF COLD FNT IS CAUSING
THE PCPN OVER NRN MN TO DIMINISH STEADILY. 12Z H85 TEMPS RANGE FM
15C AT MPX AND ABERDEEN SDAKOTA TO -12C AT THE PAS MANITOBA.
MAIN FCST CONCERNS IN THE SHORT TERM ARE RELATED TO POPS/DRYING
TREND/PTYPE AS UPSTREAM SHRTWVS/COLD FNT PROPAGATE TO THE ESE.
COLDER AND DRIER AIR WL FOLLOW TNGT/TUE IN THE NW FLOW E OF HI PRES
BLDG INTO THE NRN PLAINS.
LATE TODAY/TNGT...EXPECT SHOWERS LATE THIS AFTN UNDER DYNAMIC
FORCING IN ADVANCE OF APRCHG SHRTWV/COLD FNT AND BAND OF FGEN
ASSOCIATED WITH SRN DISTURBANCE TO IMPACT THE CWA. WITH BAND OF FGEN
AND SOMEWHAT HIER H85 DEWPTS CLOSE TO THE WI BORDER...EXPECT THE
LOWER POPS/RA TOTALS OVER THE KEWEENAW AND FAR E. THE ARRIVAL OF
COLDER/DRIER LLVL AIR IN THE WAKE OF THE COLD FROPA MAY ALLOW THE
PCPN TO MIX WITH SN AT LEAST OVER THE HIER TERRAIN OF THE N BEFORE
VIGOROUS DRYING/SUBSIDENCE ARRIVE AND END THE PCPN NW TO SE LATE
THIS AFTN/EVNG. ALTHOUGH THERE COULD BE SOME SCT CLDS IN THE UPSLOPE
AREAS NEAR LK SUP...SKIES SHOULD TREND MOCLR WITH THE VIGOROUS
DRYING. EXPECT MIN TEMPS TO BOTTOM OUT AS LO AS THE MID TEENS OVER
THE HIER TERRAIN OF THE INTERIOR W HALF PER FCST H85 TEMPS NEAR -14C
AND UPSTREAM OBS THIS MRNG.
TUE...UPR MI WL BE DOMINATED BY A STRONG NW FLOW OF COLD AIR TO THE
E OF ARCTIC HI PRES IN THE NRN PLAINS. ALTHOUGH H85 TEMPS WL BE
SUFFICIENTLY COLD FOR LES...ACYC NATURE OF THE LLVL FLOW/DRYNESS OF
THE INCOMING AIRMASS/INVERTED V LOOK TO THE FCST LLVL T/TD PROFILES
AND LINGERING LK ICE WL LIMIT LES POPS. A SHRTWV EMBEDDED IN THE NW
FLOW ALF IS FCST TO SWEEP THRU NRN ONTARIO...BUT PASSAGE OF
ACCOMPANYING DPVA/DEEP LYR QVECTOR CNVGC WELL TO THE N AND DRYNESS
OF THE AIRMASS SHOULD RESULT IN DRY WX EXCEPT PERHAPS OVER NE LK SUP
AND IN AREAS E OF MUNISING THAT WL BE CLOSER TO THE TRACK OF THE
ONTARIO DISTURBANCE. DAYTIME HEATING MAY INCRS THE POTENTIAL FOR THE
SN SHOWERS DOWNWIND OF LK SUP. BUT EVEN HERE...NO MORE THAN SCHC
POPS SEEM APPROPRIATE. THE COMBINATION OF H925 WINDS UP TO 30-35
KTS...CAA AND DAYTIME HEATING/MIXING WL RESULT IN GUSTY SFC WINDS.
GOING FCST HI TEMPS RANGING FM THE LO 30S NEAR LK SUP TO THE LO 40S
OVER THE FAR SCENTRAL SEEM REASONABLE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 455 PM EDT MON MAR 16 2015
NO SIGNIFICANT PRECIP EXPECTED THROUGH THE REST OF THE WORK WEEK.
HIGH PRESSURE CENTERED OVER S MND IA AT 00Z WILL SLOWLY SHIFT E AND
ACROSS THE UPPER GREAT LAKES WEDNESDAY THROUGH WEDNESDAY NIGHT.
THE NEXT LOW WILL BE SET UP ACROSS S HUDSON BAY THURSDAY
AFTERNOON...WITH A COLD FRONT DRAPED S OVER CENTRAL ONTARIO AND S
MANITOBA. LOOK FOR THIS FEATURE TO PUSH OVER LAKE SUPERIOR THURSDAY
NIGHT/FRIDAY MORNING. KEPT POPS TO HIGH CHANCE OVER THE N TIER
COUNTIES AND LAKE SUPERIOR DURING THE DAY FRIDAY AS THE LOW EXITS TO
FAR E ONTARIO DURING THE DAY. THERE IS THE POTENTIAL FOR A MIX OF
RAIN OR SNOW FRIDAY...WITH THE BEST CHANCE FOR ALL SNOW FAR N.
YET ANOTHER SFC HIGH WILL BE ABLE TO SIDE IN FROM THE NW FOR THE
WEEKEND. THE BEST CHANCE OF ANY LINGERING PRECIP SHOULD REMAIN NEAR
THE LAKE SUPERIOR SHORELINE AS COLDER AIR INCREASES THE POTENTIAL
FOR LAKE EFFECT SNOW SHOWERS. 850MB TEMPS OF AROUND -4C FRIDAY
AFTERNOON SHOULD FALL TO AROUND -16 TO -21C /LOWEST N/ BY SATURDAY
AFTERNOON ON STEADY N TO NW WINDS. SFC HIGHS SATURDAY MAY ONLY TOP
OUT IN THE HIGH TEENS TO MID 20S ACROSS MUCH OF THE CWA.
THE COLDEST AIR WILL SHIFT TO THE E SUNDAY EVENING...WITH 850MB
TEMPS REBOUNDING TO AROUND -11 TO -13C FOR MONDAY...AS WINDS BECOME
MORE OUT OF THE W AND ANY LINGERING LES DIMINISHES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 113 AM EDT TUE MAR 17 2015
DRY AIR MASS FLOWING INTO THE AREA AHEAD OF HIGH PRES MOVING INTO
THE NRN PLAINS WILL RESULT IN VFR CONDITIONS AT KIWD/KCMX/KSAW THRU
THIS FCST PERIOD. WITH COLDER AIR ALSO FLOWING INTO THE AREA...LAKE
SUPERIOR WILL ADD A LITTLE MOISTURE WHICH SHOULD YIELD SCT TO BKN
STRATOCU DEVELOPING UNDER DAYTIME HEATING. CLOUDS BASES WILL BE AOA
3500FT. EXPECT GUSTY WNW/NW WINDS AT ALL TERMINALS TODAY UNDER
DEEPENING MIXED LAYER (GUSTS TO 25-30KT WILL BE COMMON). WINDS
WILL DIMINISH AROUND SUNSET.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 404 PM EDT MON MAR 16 2015
NNW WINDS WILL INCREASE UP TO 30 KTS TONIGHT AND ON TUE UNDER
TIGHTENING PRES GRADIENT TO THE E OF HI PRES MOVING THRU THE
NORTHERN PLAINS. A MARGINAL GALE EVENT IS POSSIBLE ON TUE OVER
MAINLY THE E HALF...BUT MENTIONED ONLY GALE FORCE GUSTS FOR NOW.
WINDS WILL DIMINISH ON TUE NIGHT AND THEN RUN UNDER 25 KTS THE REST
OF THE WEEK. OPEN WATER REMAINS THE MOST PREVALENT OVER WESTERN LK
SUPERIOR AND OVER SCNTRL LK SUPERIOR TO THE EAST OF THE KEWEENAW
PENINSULA. EXPECT THE ICE COVER OVER THE REST OF THE LAKE TO SLOWLY
DIMINISH THROUGH THE UPCOMING WEEK DUE TO SHIFTING WINDS AND AS
DAYTIME TEMPERATURES MOST DAYS RISE ABOVE FREEZING...ESPECIALLY OVER
THE WESTERN HALF OF LK SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
628 PM CDT Wed Mar 18 2015
.UPDATE:
Issued at 600 PM CDT Wed Mar 18 2015
Updated the grids to better reflect where the E-W band of rain has
set up across nthrn MO into Pike Co, IL. It would appear that this
is going to be the ntrhn extent of the precip tonight. Also
lowered temps where it is raining to within a few degrees either
side of 40. Otherwise the fcst appears to be in decent shape with
cloudy skies and light erly flow overnight.
2%
&&
.SHORT TERM: (Through Late Tonight)
Issued at 340 PM CDT Wed Mar 18 2015
Light rain continues to work its way east from central and southeast
Missouri due to isentropic ascent of a very moist airmass from the
southern Plains into the mid Mississippi Valley. This eastward push
of the precip should persist into the evening, but very dry low
level air locked over the lower Ohio Valley may cause the coverage
and intensity of the rainfall to be somewhat less over our far
eastern counties.
Hi-res solutions are in good agreement that, with time, the light
rain will set up in a west to east axis near or perhaps just north
of the I-70 corridor where even weaker but persistent WAA will
linger into the predawn hours, with PoPs tapering off to the north
and south of this axis.
Over far northern sections of the CWA, the lack of lift and
residually dry air will likely produce a very sharp northern edge to
the rainfall...with areas near the MO/IA border possibly remaining
dry while rain will be likely for areas along and south of Highway
36. Forecasts attempt to reflect this very tight PoP gradient.
Truett
.LONG TERM: (Thursday through Next Wednesday) Issued at 340 PM
CDT Wed Mar 18 2015
The shortwave currently over Montana will dip across the
northern-central Plains Thursday forcing some weak low level
cyclogenesis over the lower Missouri Valley. All model guidance
shifts the flow from around 950mb through 800mb around to the south
ahead of the shortwave. Resulting warm advection and moisture
convergence force precip across northeast Missouri and west central
Illinois, with operational models spitting out as much as 0.25 inch
or more in those areas. This may be overbaked just a bit, but rain
seems like a good bet during the afternoon...especially since pretty
much every model is telling the same story. Have therefore
increased PoPs to categorical for northern zones, fading to likely
and then high chance toward the I-70 corridor and further south. Low
level flow will turn to the northwest in the wake of the shortwave
Thursday night. Should see rain diminish as the forcing shifts east
of the area.
West northwest flow aloft will prevail from Friday into early next
week. This will bring a series of weak shortwaves through the area,
the most impressive of which will go through Monday. This wave
still looks to produce some light precipitation, and it looks cold
enough that precip type will be questionable. Have therefore
continued the rain/snow at this time, and allowed the surface
temperatures to dictate the precip type in the forecast. The next
potential for rain will be out at the end of the forecast on
Wednesday as a deeper trof moves across the country. If we can heat
up enough ahead of the trof, there might be enough instability for
thunderstorms. As this is still 7 days out, have left mention of
storms out for now.
Temperatures look to be a bit of a roller coaster ride through the
forecast period as the northwest flow dominates. After a damp cool
day on Thursday, temps should warm up above normal for Friday and
Saturday, then drop back down normal and below Sunday and Monday,
and then rise back above normal Tuesday and Wednesday next week.
Carney
&&
.AVIATION: (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 110 PM CDT Wed Mar 18 2015
Leading edge of the rain covering the southwest third of MO just
now moving in KCOU vicinity and will continue to spread east
during the afternoon. Although the low level dry air along and
east of the Mississippi River will cause the eastward progression
to be slow, it still appears some light precip will arrive in the
STL metro during the mid-late afternoon hours. This rain will
likely persist along the I-70 corridor into the evening hours
before diminishing sometime after 06z.
Forecast soundings indicate low levels saturating over KCOU as
the evening progresses, and even though the rain should diminish
have taken cigs into MVFR cat, with vsbys also dropping into MVFR
range in fog. However, relatively drier easterly low level flow
may retard this lower cloud development in the STL metro.
Right now it appears that the KUIN area may be on the northern
fringes of the rainfall as well as the deeper low level moisture.
Because of this have maintained a dry forecast for this area, and
only gradually lowered ceilings to low end VFR by Thursday
morning.
Specifics for KSTL: Rain should continue to slowly work eastward
this afternoon. Extrapolation of the leading edge of the wet
weather suggests rain moving into the metro area between 21-23z,
with light rain then persisting throughout the evening before
tapering off after 06z. Lastest RUC data as well as 12z NAM
soundings suggest that persistent easterly low level flow will
maintain advection of relatively dry low level air. As a result,
have maintained VFR cigs/vsbys until just around daybreak Thursday.
Truett
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 38 51 40 62 / 90 60 40 10
Quincy 36 45 34 58 / 40 80 40 5
Columbia 36 46 36 62 / 90 60 30 5
Jefferson City 37 47 36 63 / 90 60 30 10
Salem 38 51 41 58 / 70 60 50 10
Farmington 37 50 38 60 / 70 50 40 10
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
350 AM CDT Tue Mar 17 2015
.DISCUSSION...
Issued at 349 AM CDT TUE MAR 17 2015
Significantly cooler temperatures are anticipated in the wake of a
strong cold front which swept through the region early this morning;
however, highs are still expected to reach or even slightly exceed
their seasonal normals in the mid to possibly upper 50s. Surface
high pressure will then build late Tuesday night, allowing temps to
drop to or below freezing by early Wednesday morning. Wildfire danger
is not expected to be as high this afternoon as in previous days, since
NNE winds will begin to diminish by the time RH drops this afternoon.
However, a period of RH less than 30% and NNE winds greater than 10
mph is expected across northwest MO and northeast KS this afternoon,
elevating the fire danger.
A shortwave trough is still progged to lift northeastward into the
region Wednesday afternoon, spreading the potential for light rain
showers across the southern and especially southeastern half of the
CWA. Measurable precipitation will likely hold off until afternoon,
due to the fairly significant dry air that will have to be overcome
before precipitation begins to fall, and amounts should be at most a
few tenths of an inch across central MO, tapering to just a few
hundredths by the MO River. Cooler air filtering in under the upper
trough and cloud cover/evaporative cooling associated with any rain
showers will make Wednesday the coolest day in the forecast period,
with highs remaining in the lower to mid 50s.
As the upper trough exits the region, warmer temperatures will begin
again by Thursday and continue into to build into the end of the
work week, bringing highs back into the 60s for both Friday and
Saturday. A few rain chances are also possible this weekend as upper
level flow flattens and allows a few weak disturbances to wash
through the area this weekend, but timing and amounts are difficult
to image at this point.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1150 PM CDT MON MAR 16 2015
A strong cold front is rapidly pushing south through the terminals
currently. Winds behind the front will increase to between 15 to 20
kts sustained with gusts in the 25 to 30 kt range. There may also be a
brief period of MVFR ceilings several hours behind the front.
Upstream observations show sporadic ~2k ft AGL clouds in northeastern
NE and northern IA. The RAP seems to depict this area reasonably well
and it slides everything to south late tonight through early Tuesday
morning. Winds will remain strong through much of the day and then
begin to decrease late tomorrow afternoon.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...Laflin
AVIATION...CDB
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
311 AM CDT Tue Mar 17 2015
.DISCUSSION...
Issued at 311 AM CDT TUE MAR 17 2015
Significantly cooler temperatures are anticipated in the wake of a
strong cold front which swept through the region early this morning;
however, highs are still expected to reach or even slightly exceed
their seasonal normals in the mid to possibly upper 50s. Surface
high pressure will then build late Tuesday night, allowing temps to
drop to or below freezing by early Wednesday morning. Fire danger is
not anticipated today, since north northeast winds will begin to
diminish by the time RH drops below 30% this afternoon.
A shortwave trough is still progged to lift northeastward into the
region Wednesday afternoon, spreading the potential for light rain
showers across the southern and especially southeastern half of the
CWA. Measurable precipitation will likely hold off until afternoon,
due to the fairly significant dry air that will have to be overcome
before precipitation begins to fall, and amounts should be at most a
few tenths of an inch across central MO, tapering to just a few
hundredths by the MO River. Cooler air filtering in under the upper
trough and cloud cover/evaporative cooling associated with any rain
showers will make Wednesday the coolest day in the forecast period,
with highs remaining in the lower to mid 50s.
As the upper trough exits the region, warmer temperatures will begin
again by Thursday and will continue to build into the end of the
work week, bringing highs back into the 60s for both Friday and
Saturday. A few rain chances are also possible this weekend as upper
level flow flattens and allows a few weak disturbances to wash
through the area this weekend, but potential rainfall amounts look
low at this point.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1150 PM CDT MON MAR 16 2015
A strong cold front is rapidly pushing south through the terminals
currently. Winds behind the front will increase to between 15 to 20
kts sustained with gusts in the 25 to 30 kt range. There may also be a
brief period of MVFR ceilings several hours behind the front.
Upstream observations show sporadic ~2k ft AGL clouds in northeastern
NE and northern IA. The RAP seems to depict this area reasonably well
and it slides everything to south late tonight through early Tuesday
morning. Winds will remain strong through much of the day and then
begin to decrease late tomorrow afternoon.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...Laflin
AVIATION...CDB
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1151 PM CDT Mon Mar 16 2015
.DISCUSSION...
Issued at 415 PM CDT MON MAR 16 2015
Immediate concern is with fire weather through very early evening.
See Fire Weather section below for details.
Overnight we will see a marked temperature change as a cold front
drops southward through northern and central MO. Strong and gusty
northerly winds will spread strong cold air advection through the
region. Expect Tuesday temperatures to be about 30 degrees colder
than todays record setting temperatures. Fortunately much of the
cloud cover behind the front is expected to think out so we should
see a good deal of sunshine to compensate for the cool down. Have to
realize that high temperatures tomorrow will actually be near
seasonal averages.
Satellite imagery shows where our next weather maker will come from.
A cutoff low off the southern tip of Baja California is expected to
lift north over the next 36-48 hours. As it moves into TX on
Wednesday it will encounter increasingly strong northwesterly flow
from the Dakotas through the TN Valley. This should shunt the bulk
of the energy eastward on Wednesday. As this system lifts northward
the southerly flow ahead of it will spread warm/moist air northward
and over a retreating area of high pressure. The resulting
isentropic ascent/warm air advection will generate an area of rain.
Question is how far north will the precipitation shield reach. Model
trends have been gradually shifting the northward extension further
south as well as delaying its arrival. This seems reasonable and
will keep the CWA dry Tuesday night. Best chance for any rain on
Wednesday/Wednesday night is south of the MO River. Even then the
rain amounts will remain on the light side.
Thursday`s PoPs remain uncertain owing to a shortwave trough
dropping southeast through the Northern Rockies and Northern Plains.
Current model solutions generate precipitation that will pass just
north of the CWA. However, all of the operational models also depict
a weaker feature that ejects eastward from CO which could linger
rain over the CWA.
Rising heights spreading eastward across the Central Plains on
Friday should allow for another shot of warming that could linger
into Saturday.
From the weekend on the medium range models are trending colder as a
back door cold front is ushered in from the Upper MS Valley in
response to falling heights as an upper trough deepens over the
eastern U.S. Some concern the model blend being used is unable to
account for this, possibly because of the bias correction that is
used. So, overall confidence on the temperature forecast for Sunday
and Monday is low and won`t be surprised if future forecasts will
have to lower temperatures.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday Night)
Issued at 1150 PM CDT MON MAR 16 2015
A strong cold front is rapidly pushing south through the terminals
currently. Winds behind the front will increase to between 15 to 20
kts sustained with gusts in the 25 to 30 kt range. There may also be a
brief period of MVFR ceilings several hours behind the front.
Upstream observations show sporadic ~2k ft AGL clouds in northeastern
NE and northern IA. The RAP seems to depict this area reasonably well
and it slides everything to south late tonight through early Tuesday
morning. Winds will remain strong through much of the day and then
begin to decrease late tomorrow afternoon.
&&
.FIRE WEATHER...
Issued at 415 PM CDT MON MAR 16 2015
Southwest winds around 20 mph with gusts up to 30 mph will continue
through 23Z and combine with RH values between 10 and 25 percent to
maintain very high to extreme fire weather for all but the far
southern CWA. The driest conditions will be along and northwest of
I-35, where RH values will be around 10 percent. Outdoor burning is strongly
discouraged as any fire that ignites will have the necessary
ingredients, including very dry grasses and brush piles, to spread
very quickly and become out of control. A Red Flag Warning remains in
effect for all but the far southeastern CWA until 8pm this evening.
Conditions will improve rapidly after sunset as the winds quickly
subside and relative humidity levels increase.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...MJ
AVIATION...CDB
FIRE WEATHER...MJ
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
825 PM MDT WED MAR 18 2015
.UPDATE...
SHOWERS PRETTY PERSISTENT NORTHEAST OF BILLINGS THIS EVENING IN
RESPONSE TO A CIRCULATION EVIDENT ON KGGW RADAR NEAR JORDAN.
DIURNAL COOLING IS CAUSING ACTIVITY TO WANE IN INTENSITY BUT
ENOUGH COVERAGE TO RAISE POPS A BIT. DO NOT EXPECT ANY MORE
THUNDERSTORMS BUT ONE LITTLE INTENSE STORM DEVELOPED NEAR
MELSTONE AND PRODUCED LIGHTNING OF AND ON ALL THE WAY TO VOLBURG.
SENT UPDATE. BORSUM
&&
.SHORT TERM...VALID FOR THU AND FRI...
FORECAST AREA WILL BE HEADED INTO A DRIER PERIOD THROUGH FRI
NIGHT. A FEW SHOWERS WERE SEEN ON RADAR MAINLY S OF KBIL THIS
AFTERNOON. SHORTWAVE TROUGH...SEEN IN WATER VAPOR IMAGERY...WAS
ROTATING INTO THE AREA AND WILL CROSS THE REGION TONIGHT. MODELS
HAD ASSOCIATED Q-VECTOR CONVERGENCE MOVING OUT OF THE AREA THIS
AFTERNOON. WINDS HAD BECOME WNW AND GUSTY ALONG AND BEHIND THE
INVERTED SURFACE TROUGH THIS AFTERNOON DUE TO MIXING. SOME CAPE
WILL PERSIST INTO THIS EVENING PER SREF PLUMES AND RAP SOUNDINGS.
THE INSTABILITY WILL BE COMPETING WITH DOWNSLOPE FLOW...SO LOWERED
POPS OVER THE PLAINS...EXCEPT FOR OVER PARTS OF THE NE ZONES
WHERE SURFACE CONVERGENCE SHOULD CREATE MORE SHOWER ACTIVITY. THE
WINDS WILL DECREASE OVERNIGHT.
UPPER RIDGING WILL BUILD OVER THE REGION THU THROUGH FRI NIGHT.
KEPT SOME LINGERING POPS OVER THE KBHK AREA THU MORNING...OTHERWISE
WENT DRY FOR THE PRECIPITATION FORECAST. GOOD MIXING ON THU WILL
PUSH TEMPERATURES INTO THE 50S AND LOWER 60S...AND PROMOTE BREEZY
CONDITIONS. MODELS SHOWED A COLD FRONT BACKDOORING INTO THE AREA
ON FRI...WHICH MAKES THE TEMPERATURE FORECAST SOMEWHAT UNCERTAIN.
850 MB TEMPERATURES AHEAD OF THIS FRONT WILL BE AROUND +12 DEGREES
C...SUPPORTING TEMPERATURES WELL INTO THE 60S. HOWEVER...THESE
READINGS COULD BE JEOPARDIZED IF THE FRONT PUSHES IT/S WAY FURTHER
INTO THE AREA THAN EXPECTED. WARM ADVECTION WILL OCCUR OVER THE
FRONTAL BOUNDARY FRI NIGHT PRODUCING SOME PRECIPITATION. MODELS
AGREED ON KEEPING THE QPF OUT OF THE REGION FOR NOW...BUT THE GFS
HAD IT CLOSE TO KBHK. THIS WILL BE ANOTHER REASON TO KEEP AN EYE
ON THE PROGRESS OF THE BACK DOOR FRONT. ARTHUR
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
LITTLE IN THE WAY OF CHANGES TO THE EXTENDED FORECAST PERIOD
AGAIN...WITH MODELS REMAINING CONSISTENT. THE OVERALL PATTERN
REMAINS PROGRESSIVE WITH A REGULAR SUCCESSION OF RIDGING AND
TROFFING.
UPPER LEVEL RIDGING WILL SHIFT ACROSS THE REGION ON
SATURDAY...WITH THE FIRST PACIFIC FRONT OF THE EXTENDED PERIOD
MOVING INTO THE REGION SATURDAY EVENING. TIMING OF THIS SYSTEM
LOOKS LIKE IT WILL ALLOW TEMPS TO CLIMB WELL INTO THE 60S IN MOST
AREAS...WITH PREFRONTAL WARMING. TEMPS WILL COOL DOWN
SIGNIFICANTLY FOR SUNDAY WITH THE COOLEST READINGS IN EASTERN
ZONES. CURRENT MODELS SHIFT MOST OF PRECIP TO THE NORTH WITH THIS
SYSTEM...BUT HAVE KEPT INHERITED SLIGHT POPS IN PLACE AT THIS
TIME...AS THIS IS A SIGNIFICANT DEPARTURE FROM PREVIOUS SEVERAL
MODEL RUNS.
RIDGING BUILDS BACK AGAIN FOR MONDAY...RESULTING IN MODERATING
TEMPS ONCE AGAIN AND ANOTHER BREAK IN THE SHOWER ACTIVITY. A
LARGER TROF BEGINS TO IMPACT THE WESTERN MOUNTAINS MONDAY
NIGHT...AND APPEARS TO BRING WIDESPREAD SHOWERS ACROSS THE REGION
BY LATE TUESDAY MORNING. MODELS VARY A BIT ON TIMING OF THIS
SYSTEM EXITING THE REGION...SO HAVE KEPT AT LEAST SLIGHT POPS IN
PLACE THROUGH THE END OF THE FORECAST PERIOD. DID RAISE POPS FOR
MONDAY NIGHT THROUGH TUESDAY NIGHT...ESPECIALLY IN THE HIGH
TERRAIN. THIS SYSTEM WILL ALSO BRING SOME MUCH COOLER TEMPERATURES
TO THE REGION...SO HAVE TRENDED TUESDAY SEVERAL DEGREES COOLER AND
WEDNESDAY SLIGHTLY COOLER. AAG
&&
.AVIATION...
SCATTERED LIGHT RAIN SHOWERS WILL CONTINUE TO MOVE EAST AND
DIMINISH OVERNIGHT...WITH SLOWLY IMPROVING CONDITIONS FROM WEST
TO EAST. VFR CONDITIONS PREVAIL...BUT AREAS OF MVFR TO IFR FLIGHT
CONDITIONS ARE POSSIBLE IN SHOWERS. HOWEVER...THE MOUNTAINS WILL
CONTINUE TO BE OBSCURED INTO THURSDAY MORNING. AAG/REIMER
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 037/062 040/067 037/064 037/056 031/060 041/051 028/043
20/B 00/B 01/B 32/W 11/B 12/W 22/W
LVM 034/059 039/066 039/065 036/053 030/059 038/046 025/044
20/U 00/B 01/B 32/W 11/B 33/W 32/W
HDN 032/063 035/069 034/067 034/058 028/062 037/052 028/046
30/B 00/B 00/B 22/W 11/B 12/W 22/W
MLS 032/058 036/063 033/059 029/052 024/054 031/050 030/043
30/B 00/B 11/B 23/W 21/B 12/W 22/W
4BQ 032/059 034/067 034/063 030/053 027/056 034/050 029/044
30/B 00/B 00/B 23/W 21/B 12/W 22/W
BHK 028/052 032/058 027/049 026/043 021/048 032/050 028/041
22/J 00/B 11/B 23/W 21/B 13/W 22/W
SHR 033/057 032/066 035/067 035/055 028/057 036/049 027/042
20/B 00/B 00/B 22/W 11/B 12/W 32/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS GLASGOW MT
814 PM MDT WED MAR 18 2015
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH FRIDAY...
UPDATE...GOING FORECAST IN OVERALL GOOD SHAPE. ONLY TWEAK WAS TO
TREND UP POPS THIS EVENING AS A SECONDARY CIRCULATION DRAGS
THROUGH NORTHEAST MONTANA. GILCHRIST
PREVIOUS DISCUSSION...SNOW IS ENDING FROM THE SOUTHWEST TO NORTHEAST AS A
MIDLEVEL SHORTWAVE OVER THE AREA PROGRESSES SOUTHEASTWARD. AREAS
WITH SNOW HAVE SEEN MODEST WARMING DURING THE DAY WHICH HAS KEPT
THE PRECIPITATION MOSTLY AS SNOW...THOUGH WET SNOW. AREAS TO THE
SOUTHWEST ARE CLEARING AND WARMING.
MOIST BOUNDARY LAYER FROM WET SNOW AND SOME THAWING/EVAPORATION
LATE THIS AFTERNOON MAY LEAD TO SOME FOG THURSDAY MORNING OVER
MUCH OF THE AREA. HAVE FOLLOWED THE HRRR RH PICTURE FOR PATCHY FOG
FORECAST.
WEAK RIDGING IN THE WAKE OF THE EXITING SHORTWAVE SHOULD GIVE
HIGHS NEAR 50 AND WILL SERVE TO MELT MOST OF THE SNOW THAT FELL
TODAY. AREAS WHERE SNOW DOES NOT MELT COULD SEE HIGHS QUITE A BIT
BELOW THE CURRENT FORECAST...BUT EXPECT THE WET SNOW TO MELT
FAIRLY QUICKLY.
LARGE SCALE NORTHWESTERLY FLOW PERSISTS THURSDAY INTO FRIDAY AND A
LITTLE RAIN/SNOW MIX IS POSSIBLE NEAR THE CANADIAN BORDER THURSDAY
EVENING AS A LITTLE SHORTWAVE ENERGY IS SEEN IN SEVERAL MODELS
AFFECTING THE AREA. MARTIN
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
THE PERIOD BEGINS INITIALLY FRIDAY EVENING WITH AN UPPER RIDGE
AXIS ALIGNED WITH THE SPINE OF THE ROCKY MOUNTAINS...A MEDIUM
WAVE TROUGH/STORM SYSTEM APPROACHING THE WEST COAST AND A STACKED
ARCTIC LOW OVER HUDSON BAY. THE APPROACHING STORM SYSTEM KNOCKED
DOWN THE RIDGE SOMEWHAT AND THE STATIONARY FRONTAL BOUNDARY WILL
BE ALIGNED NW TO SE ACROSS NORTHEAST MONTANA. OVERRUNNING MOISTURE
ALONG THE BOUNDARY WILL LIGHT MIXED PRECIPITATION FRIDAY NIGHT AND
SATURDAY. THEN BY SATURDAY EVENING THE TROUGH MOVES ACROSS THE
DIVIDE EJECTING ADDITIONAL MOISTURE TO PRODUCE MORE RAIN AND
SNOW...ALONG WITH THE POTENTIAL FOR FREEZING RAIN. CONTINUED USING
THE POT TOOL TO DETERMINE PRECIPITATION TYPE SINCE TEMPERATURES
ARE IN THE RANGE FOR A WINTRY MIX.
WITH NEAR NORMAL OR SLIGHTLY BELOW NORMAL TEMPERATURES...THE
WEEKEND WILL BE WET AND COOL. BRISK EASTERLY WINDS WILL BE ADDED
TO THE MIX OF WEATHER ALSO FOR THE WEEKEND.
THE NEXT SYSTEM COMING IN AROUND TUESDAY STILL HAS TIMING AND
GEOGRAPHICAL ISSUES. SO WILL NOT MADE ANY EDITS THERE. SCT
PREVIOUS DISCUSSION...
SYNOPTIC SET UP...LONG TERM BEGINS WITH AN ARCTIC COLD AIR LOW
OVER NORTHERN QUEBEC AND THE HUDSON BAY. MODIFIED ARCTIC AIR
SPREADS BACK FROM THIS INTO THE GREAT LAKES...THE DAKOTAS...AND
CANADIAN PRAIRIES. A LARGE RIDGE RESIDES OVER THE INTER-MOUNTAIN
WEST AND JUTS UP INTO BRITISH COLUMBIA. A COOL PACIFIC TROUGH
BUTTS UP AGAINST THIS RIDGE AT THE SHORE OF THE PACIFIC NORTHWEST
AND BRITISH COLUMBIA.
FRIDAY NIGHT THROUGH SUNDAY...FLOW WILL BE NORTHWEST WITH THE
INTER-MOUNTAIN WEST RIDGE DIMINISHING AS THE PCNW TROUGH MOVES
ACROSS THE REGION. CHANCES FOR MIXED PRECIPITATION JUMP DURING
THIS TIME AND TEMPERATURES ARE KEPT MODERATED NEAR AND JUST ABOVE
THE FREEZING LEVEL.
SUNDAY NIGHT THROUGH MONDAY NIGHT...INTER-MOUNTAIN RIDGE WILL
REBOUND/AMPLIFY AND MOVE ACROSS MONTANA. TEMPERATURES SHOULD SPIKE
UP BRIEFLY AND CONDITIONS SHOULD TURN DRY.
TUESDAY...CONFIDENCE BEGINS TO DROP OFF AT THIS POINT BUT THE
ENSEMBLES BROADLY SUGGEST THAT A SECOND SYNOPTIC TROUGH SHOULD
MOVE THROUGH THE AREA. CURRENTLY WE STAND AT THE TOP OF THE TROUGH
AND MOST OF THE LIFT ENERGY AND SUBSEQUENT PRECIPITATION WILL BE
WELL SOUTH... BUT THIS COULD QUICKLY CHANGE. SO...POPS ARE NEAR
OR JUST UNDER CLIMO DURING THIS TIME. GAH
&&
.AVIATION...
FLIGHT CATEGORY: MVFR TO VFR
SYNOPSIS: A MEDIUM WAVE TROUGH AND STORM SYSTEM WILL COMPLETE
SWINGING THROUGH EASTERN MONTANA THIS EVENING. SOME LIGHT WET SNOW
WITH LOW CEILINGS AND VISIBILITY MAY STRETCH INTO THE EVENING.
AS TEMPERATURES RISE SOME LIGHT RAIN IS ALSO A POSSIBILITY FOR THE
AFTERNOON AND EARLY EVENING. PRECIPITATION RAPIDLY TAPERS OFF BY
MIDNIGHT AND MOST RESTRICTIONS SHOULD DISAPPEAR BY 12Z FOR KSDY
AND KGDV. THE TROUGH SHOULD EXIT THE REGION DURING THE MORNING.
FOG: MODELS DO INDICATE THE POSSIBILITY OF FG OR BR FOR TONIGHT...
MAINLY FOR KGGW AND KOLF. THERE MAY BE TOO MUCH WIND ELSEWHERE.
AREA WINDS: FROM THE EAST AT ALES THAN 10 KTS BEFORE MIDNIGHT.
SWITCHING TO THE WEST AROUND 5 TO 15 KTS ON THURSDAY.
GAH/SCT
&&
.HYDROLOGY...
MINOR FLOODING IS OCCURRING ALONG FRENCHMAN CREEK IN NORTHERN
PHILLIPS COUNTY. A SMALL STREAM FLOOD ADVISORY IS IN EFFECT AS
AREAS LONG THE CREEK AND LOW WATER CROSSINGS WILL BE IMPACTED.
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS ELKO NV
750 AM PDT TUE MAR 17 2015
.SYNOPSIS...UNSEASONABLY MILD AFTERNOONS WILL CONTINUE ACROSS
NEVADA THIS WEEK. A WEAK PASSING STORM SYSTEM WILL PROVIDE A FEW
LIGHT RAIN SHOWERS THIS AFTERNOON. SOME SHOWERS AND THUNDERSTORMS
ARE EXPECTED ACROSS NYE AND WHITE PINE COUNTIES WEDNESDAY
AFTERNOON. HIGH PRESSURE...DRY WEATHER...AND NEAR RECORD WARM
TEMPERATURES RETURN THURSDAY AND FRIDAY.
&&
.UPDATE...BASED ON 12Z NAM, INCREASED POPS A SMIDGE THIS AFTERNOON
FROM GABBS TO EUREKA COUNTY TO NE ELKO COUNTY. BASED ON
INSTABILITY, A FEW LIGHTNING STRIKES ARE POSSIBLE THIS AFTERNOON
FROM NEAR MANHATTAN TO NEAR EUREKA TO NEAR THE SOUTHERN RUBY
MOUNTAINS. THIS SYSTEM IS WEAK AND THE BOUNDARY LAYER IS DRY, AS
SUCH ANY RAINFALL WILL BE LIGHT IN THE VALLEYS, A BIT MORE ON THE
MOUNTAINS. TURNER
&&
.PREV DISCUSSION... /ISSUED AT 233 AM /
SYNOPSIS...CURRENTLY THE REMNANTS OF A FRONTAL BOUNDARY SPAN FROM
MONTANA TO CALIFORNIA. LIGHT SHOWERS POSSIBLE TODAY. TEMPERATURES
WILL REMAIN ABOVE NORMAL THIS WEEK. HOWEVER...THE EASTERN PACIFIC
REGION IS BECOMING MORE ACTIVE AND THE RIDGE IS BREAKING DOWN. THIS
PATTERN WILL BE MORE CONDUCIVE TO FRONTS MOVING INTO THE GREAT BASIN.
SHORT TERM...TODAY THROUGH THURSDAY. THE LATEST SONDING FROM ELKO
HAS A PW .44 OF AN INCH WHICH IS 159 PERCENT OF NORMAL. THE
REMNANTS OF THE FRONTAL BOUNDARY SPAN ACROSS THE LKN CWA...WITH
KLRX PINGING INTO ISOLATED TO SCATTERED SHOWERS OVER
HUMBOLDT...WHICH WILL SLOWLY PUSH EASTWARD. THE MODELS HAVE BEEN
TRENDING DRIER AND DRIER EACH RUN. AT PRESENT THE HRRR IS DRIER
THAN THE GFS WITH TODAYS SYSTEM. QPF WILL BE MINIMAL WITH THIS
FIRST STORM AS THE ANTECEDENT AIRMASS HAD BEEN DESSICATED. THE
LIONS SHARE OF THE QPF WILL GO TO THE SHELDON NATIONAL WILDLIFE
REFUGE AND THE JARBIDGE WILDERNESS AREA. TEMPERATURES WILL REMAIN
ABOVE NORMAL. FOR THIS AFTERNOON FORECAST A HIGH OF 62F IN ELKO
AND 65F IN WINNEMUCCA...THE MEAN MAX TEMP FOR THOSE LOCATIONS
RESPECTIVELY IS 52F AND 56F.
LONG TERM...THURSDAY NIGHT THROUGH MONDAY. THE MODELS ARE IN GOOD
AGREEMENT WITH THE UPCOMING PATTERN BUT VARY SOMEWHAT WITH THE DEPTH
AND OF A SHORTWAVE LOW EXPECTED TO AFFECT THE REGION OVER THE
WEEKEND.
THURSDAY NIGHT THROUGH FRIDAY NIGHT. THIS PERIOD WILL BE DRY WITH
SOME NEAR RECORD HIGHS. AN EXTREMELY POSITIVE-TILT PACIFIC RIDGE
WILL CONTINUE TO EXTEND ITS AXIS THROUGH THE GREAT BASIN THURSDAY
NIGHT. THE PATTERN BECOMES MORE PROGRESSIVE LATE FRIDAY AND HIGH
PRESSURE WILL BEGIN TO MOVE EAST.
SATURDAY THROUGH SATURDAY NIGHT. AN UNSETTLED PERIOD IS EXPECTED AS
A SHORTWAVE FEATURE BRUSHES NORTHERN NEVADA. THE GFS MODEL INDICATES
SHOWERS WILL BE CONFINED TO NORTHERN NEVADA HOWEVER THE ECWMF MODEL
SUGGESTS A DEEPENING TROUGH LATE SUNDAY THAT WOULD BRING UNSETTLED
WEATHER TO MOST OF EASTERN NEVADA INCLUDING WHITE PINE COUNTY. WILL
MAINTAIN THE NOTION OF GOING WITH A BLEND OF THE GFS AND EC FOR NOW.
AT THIS TIME IT APPEARS SNOW LEVELS WILL DIP AS LOW AS 6500 FEET AS
A WEAK COLD FRONT DRAGS ACROSS NORTHERN NEVADA. TEMPERATURES WILL BE
NOTICEABLY COOLER BUT STILL ABOVE AVERAGE.
SUNDAY THROUGH MONDAY. A BROAD AREA OF HIGH PRESSURE WILL ENVELOP
THE GREAT BASIN TO BRING A RETURN TO WARM AND DRY CONDITIONS.
HOWEVER THE PATTERN WILL REMAIN PROGRESSIVE SO THERE WILL BE ANOTHER
SHORTWAVE FEATURE APPROACHING WESTERN HUMBOLDT LATE MONDAY
AFTERNOON.
AVIATION...A WEAK COLD FRONT WILL MOVE THROUGH NEVADA TODAY.
HOWEVER VFR CONDITIONS CAN BE EXPECTED TO CONTINUE AT KWMC KEKO KELY
AND KTPH THROUGH WEDNESDAY MORNING. THE KWMC ASOS IS EXPECTED TO BE
DOWN FOR MAINTENANCE THROUGH AT LEAST FRIDAY. THE TAF WILL CONTINUE
TO BE ADVERTISED AS AMD NOT SKED.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS ELKO NV
233 AM PDT TUE MAR 17 2015
.SYNOPSIS...CURRENTLY THE REMNANTS OF A FRONTAL BOUNDARY SPAN FROM
MONTANA TO CALIFORNIA. LIGHT SHOWERS POSSIBLE TODAY. TEMPERATURES
WILL REMAIN ABOVE NORMAL THIS WEEK. HOWEVER...THE EASTERN PACIFIC
REGION IS BECOMING MORE ACTIVE AND THE RIDGE IS BREAKING DOWN. THIS
PATTERN WILL BE MORE CONDUCIVE TO FRONTS MOVING INTO THE GREAT BASIN.
&&
.SHORT TERM...TODAY THROUGH THURSDAY. THE LATEST SONDING FROM ELKO
HAS A PW .44 OF AN INCH WHICH IS 159 PERCENT OF NORMAL. THE
REMNANTS OF THE FRONTAL BOUNDARY SPAN ACROSS THE LKN CWA...WITH
KLRX PINGING INTO ISOLATED TO SCATTERED SHOWERS OVER
HUMBOLDT...WHICH WILL SLOWLY PUSH EASTWARD. THE MODELS HAVE BEEN
TRENDING DRIER AND DRIER EACH RUN. AT PRESENT THE HRRR IS DRIER
THAN THE GFS WITH TODAYS SYSTEM. QPF WILL BE MINIMAL WITH THIS
FIRST STORM AS THE ANTECEDENT AIRMASS HAD BEEN DESSICATED. THE
LIONS SHARE OF THE QPF WILL GO TO THE SHELDON NATIONAL WILDLIFE
REFUGE AND THE JARBIDGE WILDERNESS AREA. TEMPERATURES WILL REMAIN
ABOVE NORMAL. FOR THIS AFTERNOON FORECAST A HIGH OF 62F IN ELKO
AND 65F IN WINNEMUCCA...THE MEAN MAX TEMP FOR THOSE LOCATIONS
RESPECTIVELY IS 52F AND 56F.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY. THE MODELS ARE IN GOOD
AGREEMENT WITH THE UPCOMING PATTERN BUT VARY SOMEWHAT WITH THE DEPTH
AND OF A SHORTWAVE LOW EXPECTED TO AFFECT THE REGION OVER THE
WEEKEND.
THURSDAY NIGHT THROUGH FRIDAY NIGHT. THIS PERIOD WILL BE DRY WITH
SOME NEAR RECORD HIGHS. AN EXTREMELY POSITIVE-TILT PACIFIC RIDGE
WILL CONTINUE TO EXTEND ITS AXIS THROUGH THE GREAT BASIN THURSDAY
NIGHT. THE PATTERN BECOMES MORE PROGRESSIVE LATE FRIDAY AND HIGH
PRESSURE WILL BEGIN TO MOVE EAST.
SATURDAY THROUGH SATURDAY NIGHT. AN UNSETTLED PERIOD IS EXPECTED AS
A SHORTWAVE FEATURE BRUSHES NORTHERN NEVADA. THE GFS MODEL INDICATES
SHOWERS WILL BE CONFINED TO NORTHERN NEVADA HOWEVER THE ECWMF MODEL
SUGGESTS A DEEPENING TROUGH LATE SUNDAY THAT WOULD BRING UNSETTLED
WEATHER TO MOST OF EASTERN NEVADA INCLUDING WHITE PINE COUNTY. WILL
MAINTAIN THE NOTION OF GOING WITH A BLEND OF THE GFS AND EC FOR NOW.
AT THIS TIME IT APPEARS SNOW LEVELS WILL DIP AS LOW AS 6500 FEET AS
A WEAK COLD FRONT DRAGS ACROSS NORTHERN NEVADA. TEMPERATURES WILL BE
NOTICEABLY COOLER BUT STILL ABOVE AVERAGE.
SUNDAY THROUGH MONDAY. A BROAD AREA OF HIGH PRESSURE WILL ENVELOP
THE GREAT BASIN TO BRING A RETURN TO WARM AND DRY CONDITIONS.
HOWEVER THE PATTERN WILL REMAIN PROGRESSIVE SO THERE WILL BE ANOTHER
SHORTWAVE FEATURE APPROACHING WESTERN HUMBOLDT LATE MONDAY
AFTERNOON.
&&
.AVIATION...A WEAK COLD FRONT WILL MOVE THROUGH NEVADA TODAY.
HOWEVER VFR CONDITIONS CAN BE EXPECTED TO CONTINUE AT KWMC KEKO KELY
AND KTPH THROUGH WEDNESDAY MORNING. THE KWMC ASOS IS EXPECTED TO BE
DOWN FOR MAINTENANCE THROUGH AT LEAST FRIDAY. THE TAF WILL CONTINUE
TO BE ADVERTISED AS AMD NOT SKED.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
97/92/92
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
822 PM MDT WED MAR 18 2015
.UPDATE...
A BACK DOOR COLD FRONT SHOULD LOWER SNOW LEVELS ACROSS THE
NORTHERN MOUNTAINS LATE THURSDAY...SO WE DECIDED TO ISSUE A WINTER
STORM WATCH. SEVERAL INCHES TO LOCALLY NEAR 1 FOOT OF SNOW WILL BE
POSSIBLE. ALSO ADDED FOG TO THE FORECAST FOR THE MORENO VALLEY
LATE TONIGHT DUE TO ALL THE MOISTURE THAT WILL SOCK IN THAT AREA.
CONSIDERED FORECASTING FOG FOR OTHER LOCATIONS...BUT SKY COVER
SHOULD STAY THICK ENOUGH TO PREVENT MUCH DEVELOPMENT.
44
&&
.PREV DISCUSSION...551 PM MDT WED MAR 18 2015...
.AVIATION...
00Z TAF CYCLE
AN AREA OF LIGHT RAIN WITH GUSTY WINDS OVER CENTRAL NM WILL CONTINUE
PROGRESSING NORTHEAST ACROSS THE ABQ METRO THEN INTO THE NORTHERN
MTS AND NORTHEAST PLAINS OVERNIGHT. VFR CIGS AND VSBYS DOMINATE THIS
AREA OF RAIN HOWEVER SOME LOCALIZED REDUCTIONS TO 5SM ARE POSSIBLE...
ALONG WITH MT OBSCURATIONS. ABUNDANT LOW LEVEL MOISTURE IN PLACE AND
WEAK SURFACE CONVERGENCE MAY FAVOR PATCHY FOG FROM KAEG/KSAF/KABQ
NORTHEAST TO KLVS AROUND SUNRISE. HOWEVER...WILL NOT INCLUDE IN 00Z
TAF CYCLE JUST YET AND WILL ASSESS AFTER SEEING HOW MUCH PRECIP FALLS
OUT OF THE CURRENT AREA OF RAIN. IF MODELS CONTINUE TO TREND TOWARD
FOG WILL INCLUDE IN 06Z ISSUANCE. THURSDAY IS EXPECTED TO BE A DYNAMIC
DAY AS A STRONG COLD FRONT MOVES SW INTO THE STATE AND AN UPPER WAVE
ARRIVES FROM THE WEST. SHOWERS/STORMS WILL DEVELOP ONCE AGAIN BY LATE
MORNING AND BECOME A LARGE AREA OF RAIN AND MT SNOW BY THURSDAY
EVENING.
GUYER
&&
.PREV DISCUSSION...328 PM MDT WED MAR 18 2015...
.SYNOPSIS...
AN UPPER LOW NEAR SAN DIEGO WILL COMBINE WITH PLENTY OF LOW LEVEL MOISTURE
TO BRING SCATTERED TO NUMEROUS SHOWERS TO MUCH OF CENTRAL AND
NORTHERN NEW MEXICO TONIGHT. THIS SAME UPPER LOW WILL COMBINE
WITH ANOTHER UPPER LEVEL STORM SYSTEM DROPPING IN FROM THE
NORTHWEST ALONG WITH A BACKDOOR COLD FRONT TO PRODUCE NUMEROUS
SHOWERS TO THE NORTHERN TWO THIRDS OF NEW MEXICO THURSDAY AND
THURSDAY NIGHT. BRIEF HEAVY RAIN AND SMALL HAIL IS LIKELY WITH THE
STRONGER SHOWERS AND THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.
PLENTIFUL RESIDUAL MOISTURE WILL KEEP SCATTERED SHOWERS IN THE
FORECAST FRIDAY...WITH A DRYING AND WARMING TREND EXPECTED FOR THE
WEEKEND.
&&
.DISCUSSION...
BAND OF LIGHT TO MODERATE RAIN EXTENDS FROM CATRON AND WESTERN
SOCORRO COUNTIES NORTHWARD INTO EASTERN CIBOLA AND SOUTHEAST
MCKINLEY COUNTIES WILL CONTINUE TO SLOWLY MOVE EASTWARD THIS EVENING.
BIG QUESTION IS WHETHER OR NOT THIS BAND WILL MAKE THE TRIP DOWNWARD
INTO THE RIO GRANDE VALLEY. 18Z NAM12 AND 18Z HRRR MODELS
INDICATING THAT THIS LINE...IN FACT...WILL MAKE IT INTO THE RGV AND
GIVEN THE CURRENT TEMP OF 66F AT THE ABQ SUNPORT AND THE 40F
DEWPOINT TEMPERATURE...SUSPECT THAT THESE HIGH RESOLUTION MODELS
ARE ON TO SOMETHING. WAVE/SPEED MAX MOVING UP FROM THE SOUTH WILL
SHIFT MAIN FOCUS FOR SHOWERS LATE TONIGHT TO THE SOUTHWEST
MOUNTAINS. ADDITIONALLY...SHOWERS WILL ALSO FOCUS OVER THE
NORTHEAST PLAINS LATE TONIGHT AND THURSDAY MORNING AS A BACKDOOR
FRONT DROPS IN. NORTHERN STREAM SHORT- WAVE TROUGH STILL PROGGED
TO PHASE WITH THE SOUTHERN STREAM CLOSED LOW OVER ERN AZ/WRN NM THURSDAY.
GOOD LAPSE RATES/INSTABILITY...ASSOCIATED LIFT FROM 100KT SUBTROPICAL
JET OVER SE NM AND COPIOUS AMOUNTS OF PACIFIC MOISTURE WILL
COMBINE WITH A BACKDOOR COLD FRONT TO GENERATE NUMEROUS SHOWERS
AND THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.
UPPER LOW TO THE SOUTHWEST REMAINS IN TACT AND PASSES EASTWARD WELL
SOUTH OF NM WHILE THE NRN STREAM TROUGH SHEARS APART AND FILLS
OVER THE STATE FRIDAY AND FRIDAY NIGHT. PLENTY OF RESIDUAL
MOISTURE WILL COMBINE WITH DECENT LAPSE RATES/INSTABILITY AND
DAYTIME HEATING TO PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS
OVER THE WESTERN AND NORTHERN MOUNTAINS FRIDAY AFTERNOON AND
EVENING.
ON SATURDAY...WEST COAST RIDGE CONTINUES TO PROPAGATE EAST AND FOLD
OVER AND THE RESULTING HIGHER HEIGHTS AND A VERY DRY NORTHERLY
FLOW ALOFT LIMIT SHOWERS CHANCES SATURDAY AND ALL BUT ELIMINATE
CHANCES SUNDAY INTO EARLY NEXT WEEK. MODELS AGREE THAT A DRY ZONAL
FLOW SETS UP OVER THE SOUTHWEST U.S. EARLY NEXT WEEK WITH THE
POTENTIAL FOR A TROUGH DROPPING SEWD INTO THROUGH COLORADO AND
CLIPPING THE NE AROUND MIDWEEK. 33
&&
.FIRE WEATHER...
WELL ABOVE NORMAL PWATS OVER THE AREA TO PERSIST THROUGH FRIDAY WITH
A GRADUAL DRYING TREND TAKING PWATS DOWN TO NEAR NORMAL VALUES FOR
MARCH BY THE END OF THE WEEKEND. FURTHER DRYING FORECAST EARLY NEXT
WEEK WITH THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS AS
EARLY AS TUESDAY.
CHANCES FOR WETTING PRECIPITATION WILL BE ON THE INCREASE THROUGH
THURSDAY NIGHT AS A SLOW MOVING TROUGH APPROACHES FROM THE WEST AND
A BACKDOOR COLD FRONT MAKES SOUTHWEST PROGRESS. THE 12Z MODEL
SOLUTIONS AND RESULTING MOS ARE WETTER THAN THE PAST SEVERAL RUNS
FOR CENTRAL AND NORTHERN NEW MEXICO LATE THURSDAY THROUGH THURSDAY
NIGHT DUE TO THE TIMING OF THE BACKDOOR FRONT COINCIDING WITH THE
NORTHERN STREAM TROUGH DROPPING INTO THE AREA AND PHASING WITH THE
SLOW MOVING SOUTHERN STREAM TROUGH. NOT MUCH IN THE WAY OF LIGHTNING
ACTIVITY LATE THIS AFTERNOON THROUGH TONIGHT...BUT AN UPTICK IS
EXPECTED THURSDAY AND FRIDAY.
A DRYING/WARMING TREND TO KICK-OFF SATURDAY WITH TEMPERATURES
RETURNING TO ABOVE NORMAL. A LAST ROUND OF DAYTIME HEATING TRIGGERED
CONVECTION IS FORECAST SATURDAY...ALTHOUGH COVERAGE OF WETTING
PRECIPITATION WILL BE VERY LOW. VENT RATES ARE FORECAST TO IMPROVE
THROUGH THE WEEKEND WITH THE WARMING AND INCREASING WIND PROFILE.
EARLY NEXT WEEK WILL FEATURE INCREASING WESTERLY FLOW...CONTINUED
DRYING WITH INCREASING HAINES...MIXING AND VENT RATES. POTENTIAL FOR
CRITICAL FIRE WEATHER CONDITIONS ON THE UPTREND TUESDAY AND MAY
EXTEND INTO WEDNESDAY PRIOR TO A COLD FRONT...ALTHOUGH THE PRECEDING
LEE SIDE TROUGH DOES NOT LOOK PARTICULARLY DEEP AT 1001MB. MODERATE
FORECASTER CONFIDENCE ON THE MON/TUE FORECAST AT THIS TIME GIVEN
GOOD AGREEMENT BETWEEN THE 12Z GFS AND ECMWF SOLUTIONS. 11
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY MORNING
FOR THE FOLLOWING ZONES...NMZ510>515.
&&
$$
44
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
551 PM MDT WED MAR 18 2015
.AVIATION...
00Z TAF CYCLE
AN AREA OF LIGHT RAIN WITH GUSTY WINDS OVER CENTRAL NM WILL CONTINUE
PROGRESSING NORTHEAST ACROSS THE ABQ METRO THEN INTO THE NORTHERN
MTS AND NORTHEAST PLAINS OVERNIGHT. VFR CIGS AND VSBYS DOMINATE THIS
AREA OF RAIN HOWEVER SOME LOCALIZED REDUCTIONS TO 5SM ARE POSSIBLE...
ALONG WITH MT OBSCURATIONS. ABUNDANT LOW LEVEL MOISTURE IN PLACE AND
WEAK SURFACE CONVERGENCE MAY FAVOR PATCHY FOG FROM KAEG/KSAF/KABQ
NORTHEAST TO KLVS AROUND SUNRISE. HOWEVER...WILL NOT INCLUDE IN 00Z
TAF CYCLE JUST YET AND WILL ASSESS AFTER SEEING HOW MUCH PRECIP FALLS
OUT OF THE CURRENT AREA OF RAIN. IF MODELS CONTINUE TO TREND TOWARD
FOG WILL INCLUDE IN 06Z ISSUANCE. THURSDAY IS EXPECTED TO BE A DYNAMIC
DAY AS A STRONG COLD FRONT MOVES SW INTO THE STATE AND AN UPPER WAVE
ARRIVES FROM THE WEST. SHOWERS/STORMS WILL DEVELOP ONCE AGAIN BY LATE
MORNING AND BECOME A LARGE AREA OF RAIN AND MT SNOW BY THURSDAY
EVENING.
GUYER
&&
.PREV DISCUSSION...328 PM MDT WED MAR 18 2015...
.SYNOPSIS...
AN UPPER LOW NEAR SAN DIEGO WILL COMBINE WITH PLENTY OF LOW LEVEL MOISTURE
TO BRING SCATTERED TO NUMEROUS SHOWERS TO MUCH OF CENTRAL AND
NORTHERN NEW MEXICO TONIGHT. THIS SAME UPPER LOW WILL COMBINE
WITH ANOTHER UPPER LEVEL STORM SYSTEM DROPPING IN FROM THE
NORTHWEST ALONG WITH A BACKDOOR COLD FRONT TO PRODUCE NUMEROUS
SHOWERS TO THE NORTHERN TWO THIRDS OF NEW MEXICO THURSDAY AND
THURSDAY NIGHT. BRIEF HEAVY RAIN AND SMALL HAIL IS LIKELY WITH THE
STRONGER SHOWERS AND THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.
PLENTIFUL RESIDUAL MOISTURE WILL KEEP SCATTERED SHOWERS IN THE
FORECAST FRIDAY...WITH A DRYING AND WARMING TREND EXPECTED FOR THE
WEEKEND.
&&
.DISCUSSION...
BAND OF LIGHT TO MODERATE RAIN EXTENDS FROM CATRON AND WESTERN
SOCORRO COUNTIES NORTHWARD INTO EASTERN CIBOLA AND SOUTHEAST
MCKINLEY COUNTIES WILL CONTINUE TO SLOWLY MOVE EASTWARD THIS EVENING.
BIG QUESTION IS WHETHER OR NOT THIS BAND WILL MAKE THE TRIP DOWNWARD
INTO THE RIO GRANDE VALLEY. 18Z NAM12 AND 18Z HRRR MODELS
INDICATING THAT THIS LINE...IN FACT...WILL MAKE IT INTO THE RGV AND
GIVEN THE CURRENT TEMP OF 66F AT THE ABQ SUNPORT AND THE 40F
DEWPOINT TEMPERATURE...SUSPECT THAT THESE HIGH RESOLUTION MODELS
ARE ON TO SOMETHING. WAVE/SPEED MAX MOVING UP FROM THE SOUTH WILL
SHIFT MAIN FOCUS FOR SHOWERS LATE TONIGHT TO THE SOUTHWEST
MOUNTAINS. ADDITIONALLY...SHOWERS WILL ALSO FOCUS OVER THE
NORTHEAST PLAINS LATE TONIGHT AND THURSDAY MORNING AS A BACKDOOR
FRONT DROPS IN. NORTHERN STREAM SHORT- WAVE TROUGH STILL PROGGED
TO PHASE WITH THE SOUTHERN STREAM CLOSED LOW OVER ERN AZ/WRN NM THURSDAY.
GOOD LAPSE RATES/INSTABILITY...ASSOCIATED LIFT FROM 100KT SUBTROPICAL
JET OVER SE NM AND COPIOUS AMOUNTS OF PACIFIC MOISTURE WILL
COMBINE WITH A BACKDOOR COLD FRONT TO GENERATE NUMEROUS SHOWERS
AND THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.
UPPER LOW TO THE SOUTHWEST REMAINS IN TACT AND PASSES EASTWARD WELL
SOUTH OF NM WHILE THE NRN STREAM TROUGH SHEARS APART AND FILLS
OVER THE STATE FRIDAY AND FRIDAY NIGHT. PLENTY OF RESIDUAL
MOISTURE WILL COMBINE WITH DECENT LAPSE RATES/INSTABILITY AND
DAYTIME HEATING TO PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS
OVER THE WESTERN AND NORTHERN MOUNTAINS FRIDAY AFTERNOON AND
EVENING.
ON SATURDAY...WEST COAST RIDGE CONTINUES TO PROPAGATE EAST AND FOLD
OVER AND THE RESULTING HIGHER HEIGHTS AND A VERY DRY NORTHERLY
FLOW ALOFT LIMIT SHOWERS CHANCES SATURDAY AND ALL BUT ELIMINATE
CHANCES SUNDAY INTO EARLY NEXT WEEK. MODELS AGREE THAT A DRY ZONAL
FLOW SETS UP OVER THE SOUTHWEST U.S. EARLY NEXT WEEK WITH THE
POTENTIAL FOR A TROUGH DROPPING SEWD INTO THROUGH COLORADO AND
CLIPPING THE NE AROUND MIDWEEK. 33
&&
.FIRE WEATHER...
WELL ABOVE NORMAL PWATS OVER THE AREA TO PERSIST THROUGH FRIDAY WITH
A GRADUAL DRYING TREND TAKING PWATS DOWN TO NEAR NORMAL VALUES FOR
MARCH BY THE END OF THE WEEKEND. FURTHER DRYING FORECAST EARLY NEXT
WEEK WITH THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS AS
EARLY AS TUESDAY.
CHANCES FOR WETTING PRECIPITATION WILL BE ON THE INCREASE THROUGH
THURSDAY NIGHT AS A SLOW MOVING TROUGH APPROACHES FROM THE WEST AND
A BACKDOOR COLD FRONT MAKES SOUTHWEST PROGRESS. THE 12Z MODEL
SOLUTIONS AND RESULTING MOS ARE WETTER THAN THE PAST SEVERAL RUNS
FOR CENTRAL AND NORTHERN NEW MEXICO LATE THURSDAY THROUGH THURSDAY
NIGHT DUE TO THE TIMING OF THE BACKDOOR FRONT COINCIDING WITH THE
NORTHERN STREAM TROUGH DROPPING INTO THE AREA AND PHASING WITH THE
SLOW MOVING SOUTHERN STREAM TROUGH. NOT MUCH IN THE WAY OF LIGHTNING
ACTIVITY LATE THIS AFTERNOON THROUGH TONIGHT...BUT AN UPTICK IS
EXPECTED THURSDAY AND FRIDAY.
A DRYING/WARMING TREND TO KICK-OFF SATURDAY WITH TEMPERATURES
RETURNING TO ABOVE NORMAL. A LAST ROUND OF DAYTIME HEATING TRIGGERED
CONVECTION IS FORECAST SATURDAY...ALTHOUGH COVERAGE OF WETTING
PRECIPITATION WILL BE VERY LOW. VENT RATES ARE FORECAST TO IMPROVE
THROUGH THE WEEKEND WITH THE WARMING AND INCREASING WIND PROFILE.
EARLY NEXT WEEK WILL FEATURE INCREASING WESTERLY FLOW...CONTINUED
DRYING WITH INCREASING HAINES...MIXING AND VENT RATES. POTENTIAL FOR
CRITICAL FIRE WEATHER CONDITIONS ON THE UPTREND TUESDAY AND MAY
EXTEND INTO WEDNESDAY PRIOR TO A COLD FRONT...ALTHOUGH THE PRECEDING
LEE SIDE TROUGH DOES NOT LOOK PARTICULARLY DEEP AT 1001MB. MODERATE
FORECASTER CONFIDENCE ON THE MON/TUE FORECAST AT THIS TIME GIVEN
GOOD AGREEMENT BETWEEN THE 12Z GFS AND ECMWF SOLUTIONS. 11
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BISMARCK ND
859 PM CDT WED MAR 18 2015
.UPDATE...
ISSUED AT 853 PM CDT WED MAR 18 2015
PERSISTENT LIGHT SNOW WILL REQUIRE A LARGER AND LONGER PERIOD OF
SNOW ACROSS THE NORTH CENTRAL INTO THE JAMES RIVER VALLEY. DID
THAT WITH THIS UPDATE. VISIBILITIES IN THE SNOW SEEM TO CONFIRM
ITS FAIRLY LIGHT...WITH VSBYS GENERALLY A MILE OR ABOVE...ALSO
CONFIRMED BY DOT CAMERAS...AND SURFACE TEMPERATURES ARE 33 TO 36
MOST AREAS SO THERE IS SOME MELTING. NDOT TRAVEL MAP SHOWS WET AND
SLUSHY AREAS ACROSS THE AREA OF RADAR COVERAGE. SO A BOOST TO THE
POPS IS THE MAIN CHANGE FOR THE EVENING.
UPDATE ISSUED AT 636 PM CDT WED MAR 18 2015
RADAR AND SURFACE REPORTS SHOW A BAND OF MOSTLY SNOW ACROSS NORTH
CENTRAL NORTH DAKOTA. GLASGOW RADAR NOW SHOWING THE SNOW WILL TAPER
OFF AT WILLISTON. WILL INCORPORATE THESE TRENDS IN THE UPDATED
FORECAST AND GO CATEGORICAL SNOW NORTH THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 342 PM CDT WED MAR 18 2015
HIGHLIGHTS OF THE SHORT TERM ARE SNOWFALL AND FOG THROUGH TONIGHT.
AS OF 20 UTC...A BAND OF LIGHT TO MODERATE SNOW WAS CENTERED ALONG
A LINE FROM WATFORD CITY THROUGH JAMESTOWN. THIS BAND IS EXPECTED
TO CONTINUE TO PROPAGATE NORTHEAST THROUGH THE EVENING AND SLOWLY
WEAKEN...BECOMING CENTERED ALONG THE US HIGHWAY 2 CORRIDOR AS
DEPICTED BY THE 17-19 UTC HRRR AND 18 UTC NAM SOLUTIONS.
ADDITIONAL ACCUMULATIONS OF LESS THAN ONE INCH ARE EXPECTED GIVEN
THE VERY LOW SNOW RATIOS THAT HAVE BEEN OBSERVED THROUGH THE DAY.
DID ADD A MENTION OF FOG ACROSS THE WEST TONIGHT WITH STRATUS
BUILD DOWN AS WINDS BECOME LIGHT IN THE INVERTED TROUGH AXIS.
SCATTERED RAIN AND SNOW SHOWERS MAY LINGER INTO THURSDAY MORNING
IN ASSOCIATION WITH THE DEPARTING UPPER LEVEL WAVE...WITH MOSTLY
SUNNY CONDITIONS EXPECTED BY AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM CDT WED MAR 18 2015
AN ACTIVE LONG TERM PERIOD. THE HUDSON BAY LOW SHIFTS EAST THROUGH
THE PERIOD ALLOWING FOR A MORE ENERGETIC/MOIST PACIFIC FLOW WITH
SEVERAL SHORTWAVES TO MOVE ACROSS NORTH DAKOTA. ONE LAST SHORTWAVE
ASSOCIATED WITH THE HUDSON BAY LOW WILL PUSH A CLIPPER SYSTEM ACROSS
MAINLY NORTH CENTRAL INTO EAST CENTRAL NORTH DAKOTA FRIDAY. HAVE
INCREASED POPS TO LIKELY CATEGORY IN THE NORTH CENTRAL/TURTLE
MOUNTAINS WITH ALL MODELS DEPICTING THE SHORTWAVE AND ASSOCIATED
PRECIPITATION ACROSS THIS AREA. COULD BE AROUND ONE INCH IN THE
TURTLE MOUNTAINS. POPS TAPER OFF TO BELOW MEASURABLE FARTHER SOUTH
AND WEST. AS THE FLOW TRANSITIONS FROM NORTHWEST TO ZONAL FLOW...A
SERIES OF SHORTWAVES SHIFTING EAST FROM THE PACIFIC QUICKLY MOVE
TOWARD NORTH DAKOTA. A WEAK SHORTWAVE SLIDES THROUGH SATURDAY WITH A
CHANCE OF SNOW/RAIN MOSTLY AFFECTING NORTHWEST THROUGH NORTH CENTRAL
NORTH DAKOTA. THEREAFTER...TWO SIGNIFICANT MID LEVEL SHORTWAVES WILL
NEED MONITORING. THE FIRST SHORTWAVE COMES THROUGH WESTERN AND
CENTRAL NORTH DAKOTA...NEGATIVELY TILTED...SUNDAY INTO SUNDAY NIGHT.
THIS WILL PRODUCE WIDESPREAD SNOW ACROSS CENTRAL NORTH DAKOTA WITH
THE GFS AND ECMWF DEPICTING TWO TO THREE TENTHS OF LIQUID...OR
POSSIBLY 2 TO 3.5 INCHES OF SNOW FOR PORTIONS OF CENTRAL NORTH
DAKOTA. TEMPERATURES SHOULD BE WARMER SOUTHWEST FOR SNOW CHANGING
OVER TO RAIN IN THE AFTERNOON. A BRIEF TRANSITORY RIDGE SLIDES BY
MONDAY/MONDAY NIGHT BEFORE THE NEXT POTENT SHORTWAVE ARRIVES
TUESDAY/WEDNESDAY. THE GFS IS FARTHER SOUTH WITH THE LOW PRESSURE
COMPLEX...SLIDING THROUGH CENTRAL/NORTHERN SOUTH DAKOTA RESULTING IN
COLDER AIR TO BE DRAWN INTO THE LOW WITH WIDESPREAD SNOW FOR
CENTRAL/SOUTHERN NORTH DAKOTA. THE ECMWF IS FARTHER NORTH WITH THIS
SYSTEM AND PRODUCES SOME LIGHT PRECIPITATION IN THE WARM AIR
ADVECTION TUESDAY FOLLOWED BY A DRY SLOT. SOME SNOW SHOWERS DEVELOP
ON THE BACK SIDE OF THE LOW WITH COLD AIR ADVECTION COMMENCING
TUESDAY NIGHT INTO WEDNESDAY. OVERALL THE ECMWF IS WEAKER WITH
REGARDS TO QPF THAN THE GFS. WILL ALSO NEED TO MONITOR THIS IN THE
COMING DAYS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 636 PM CDT WED MAR 18 2015
TROUGH OF LOW PRESSURE IS LIFTING NORTH ACROSS NORTHERN NORTH
DAKOTA THIS EVENING. SNOW WILL REDUCE VSBYS AND CEILINGS TO IFR
CONDITIONS ACROSS KMOT THIS EVENING. OTHERWISE KISN-KDIK- KBIS-
KJMS WILL GENERALLY SEE VFR. AS THE SYSTEM PIVOTS LATE TONIGHT
MVFR/IFR CONDITIONS WILL RETURN TO TAF SITES.
&&
.HYDROLOGY...
ISSUED AT 342 PM CDT WED MAR 18 2015
THE WILLOW CREEK NEAR WILLOW CITY IS FORECAST TO CONTINUE TO RISE
INTO THURSDAY...CRESTING JUST BELOW FLOOD STAGE. HOWEVER...PRECIPITATION
THIS WEEKEND INTO NEXT WEEK MAY LEAD TO ADDITIONAL RISES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...AYD
LONG TERM...KS
AVIATION...WAA
HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
643 PM CDT WED MAR 18 2015
.UPDATE...
ISSUED AT 636 PM CDT WED MAR 18 2015
RADAR AND SURFACE REPORTS SHOW A BAND OF MOSTLY SNOW ACROSS NORTH
CENTRAL NORTH DAKOTA. GLASGOW RADAR NOW SHOWING THE SNOW WILL TAPER
OFF AT WILLISTON. WILL INCORPORATE THESE TRENDS IN THE UPDATED
FORECAST AND GO CATEGORICAL SNOW NORTH THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 342 PM CDT WED MAR 18 2015
HIGHLIGHTS OF THE SHORT TERM ARE SNOWFALL AND FOG THROUGH TONIGHT.
AS OF 20 UTC...A BAND OF LIGHT TO MODERATE SNOW WAS CENTERED ALONG
A LINE FROM WATFORD CITY THROUGH JAMESTOWN. THIS BAND IS EXPECTED
TO CONTINUE TO PROPAGATE NORTHEAST THROUGH THE EVENING AND SLOWLY
WEAKEN...BECOMING CENTERED ALONG THE US HIGHWAY 2 CORRIDOR AS
DEPICTED BY THE 17-19 UTC HRRR AND 18 UTC NAM SOLUTIONS.
ADDITIONAL ACCUMULATIONS OF LESS THAN ONE INCH ARE EXPECTED GIVEN
THE VERY LOW SNOW RATIOS THAT HAVE BEEN OBSERVED THROUGH THE DAY.
DID ADD A MENTION OF FOG ACROSS THE WEST TONIGHT WITH STRATUS
BUILD DOWN AS WINDS BECOME LIGHT IN THE INVERTED TROUGH AXIS.
SCATTERED RAIN AND SNOW SHOWERS MAY LINGER INTO THURSDAY MORNING
IN ASSOCIATION WITH THE DEPARTING UPPER LEVEL WAVE...WITH MOSTLY
SUNNY CONDITIONS EXPECTED BY AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM CDT WED MAR 18 2015
AN ACTIVE LONG TERM PERIOD. THE HUDSON BAY LOW SHIFTS EAST THROUGH
THE PERIOD ALLOWING FOR A MORE ENERGETIC/MOIST PACIFIC FLOW WITH
SEVERAL SHORTWAVES TO MOVE ACROSS NORTH DAKOTA. ONE LAST SHORTWAVE
ASSOCIATED WITH THE HUDSON BAY LOW WILL PUSH A CLIPPER SYSTEM ACROSS
MAINLY NORTH CENTRAL INTO EAST CENTRAL NORTH DAKOTA FRIDAY. HAVE
INCREASED POPS TO LIKELY CATEGORY IN THE NORTH CENTRAL/TURTLE
MOUNTAINS WITH ALL MODELS DEPICTING THE SHORTWAVE AND ASSOCIATED
PRECIPITATION ACROSS THIS AREA. COULD BE AROUND ONE INCH IN THE
TURTLE MOUNTAINS. POPS TAPER OFF TO BELOW MEASURABLE FARTHER SOUTH
AND WEST. AS THE FLOW TRANSITIONS FROM NORTHWEST TO ZONAL FLOW...A
SERIES OF SHORTWAVES SHIFTING EAST FROM THE PACIFIC QUICKLY MOVE
TOWARD NORTH DAKOTA. A WEAK SHORTWAVE SLIDES THROUGH SATURDAY WITH A
CHANCE OF SNOW/RAIN MOSTLY AFFECTING NORTHWEST THROUGH NORTH CENTRAL
NORTH DAKOTA. THEREAFTER...TWO SIGNIFICANT MID LEVEL SHORTWAVES WILL
NEED MONITORING. THE FIRST SHORTWAVE COMES THROUGH WESTERN AND
CENTRAL NORTH DAKOTA...NEGATIVELY TILTED...SUNDAY INTO SUNDAY NIGHT.
THIS WILL PRODUCE WIDESPREAD SNOW ACROSS CENTRAL NORTH DAKOTA WITH
THE GFS AND ECMWF DEPICTING TWO TO THREE TENTHS OF LIQUID...OR
POSSIBLY 2 TO 3.5 INCHES OF SNOW FOR PORTIONS OF CENTRAL NORTH
DAKOTA. TEMPERATURES SHOULD BE WARMER SOUTHWEST FOR SNOW CHANGING
OVER TO RAIN IN THE AFTERNOON. A BRIEF TRANSITORY RIDGE SLIDES BY
MONDAY/MONDAY NIGHT BEFORE THE NEXT POTENT SHORTWAVE ARRIVES
TUESDAY/WEDNESDAY. THE GFS IS FARTHER SOUTH WITH THE LOW PRESSURE
COMPLEX...SLIDING THROUGH CENTRAL/NORTHERN SOUTH DAKOTA RESULTING IN
COLDER AIR TO BE DRAWN INTO THE LOW WITH WIDESPREAD SNOW FOR
CENTRAL/SOUTHERN NORTH DAKOTA. THE ECMWF IS FARTHER NORTH WITH THIS
SYSTEM AND PRODUCES SOME LIGHT PRECIPITATION IN THE WARM AIR
ADVECTION TUESDAY FOLLOWED BY A DRY SLOT. SOME SNOW SHOWERS DEVELOP
ON THE BACK SIDE OF THE LOW WITH COLD AIR ADVECTION COMMENCING
TUESDAY NIGHT INTO WEDNESDAY. OVERALL THE ECMWF IS WEAKER WITH
REGARDS TO QPF THAN THE GFS. WILL ALSO NEED TO MONITOR THIS IN THE
COMING DAYS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 636 PM CDT WED MAR 18 2015
TROUGH OF LOW PRESSURE IS LIFTING NORTH ACROSS NORTHERN NORTH
DAKOTA THIS EVENING. SNOW WILL REDUCE VSBYS AND CEILINGS TO IFR
CONDITIONS ACROSS KMOT THIS EVENING. OTHERWISE KISN-KDIK- KBIS-
KJMS WILL GENERALLY SEE VFR. AS THE SYSTEM PIVOTS LATE TONIGHT
MVFR/IFR CONDITIONS WILL RETURN TO TAF SITES.
&&
.HYDROLOGY...
ISSUED AT 342 PM CDT WED MAR 18 2015
THE WILLOW CREEK NEAR WILLOW CITY IS FORECAST TO CONTINUE TO RISE
INTO THURSDAY...CRESTING JUST BELOW FLOOD STAGE. HOWEVER...PRECIPITATION
THIS WEEKEND INTO NEXT WEEK MAY LEAD TO ADDITIONAL RISES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...AYD
LONG TERM...KS
AVIATION...WAA
HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
637 AM EDT TUE MAR 17 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE SOUTH ACROSS THE REGION THIS MORNING...WITH
MUCH COOLER AND DRIER AIR SETTLING IN BEHIND IT. A CHANCE OF RAIN
WILL OCCUR ON THURSDAY INTO FRIDAY...WITH DRY CONDITIONS AND
SLIGHTLY WARMER TEMPERATURES FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE ILN CWA WILL SPEND ANOTHER FEW HOURS IN A WARM AIR MASS AHEAD
OF AN APPROACHING COLD FRONT...BEFORE THIS BRIEF PERIOD OF
WELL-ABOVE-NORMAL TEMPERATURES COMES TO AN END. THE SURFACE COLD
FRONT CURRENTLY EXTENDS FROM AROUND FORT WAYNE TO TOLEDO.
HOWEVER...BASED ON THETA-E AND WIND PLOTS AT VARIOUS LEVELS ON
RECENT NAM/RAP RUNS...THE FRONT IS THE MOST WELL-DEFINED AT 925MB.
UNTIL THE FRONT ARRIVES...TEMPERATURES WILL CONTINUE TO SHOW
ALMOST NO DECREASE...WITH GUSTY WSW FLOW.
THE TEMPERATURE FORECAST FOR TODAY IS A CHALLENGE...BECAUSE THE
FRONT WILL BE COMING THROUGH THE REGION DURING THE TYPICAL TIME
PERIOD OF THE LARGEST DIURNAL SWINGS...BUT WILL BE CLEAR THROUGH
THE AREA BEFORE THE END OF THE AFTERNOON. IT IS OBVIOUS THAT THERE
WILL NOT BE A TYPICAL DIURNAL TRACE FOR TEMPERATURES...BUT THIS
ALSO DOES NOT LOOK LIKE A SITUATION WITH STEADILY FALLING
TEMPERATURES THROUGH THE DAY. RATHER THAN A CURVE...THE
TEMPERATURE TRACE TODAY MAY END UP LIKE MORE OF A ZIG-ZAG...WITH
VALUES THAT MOVE VERY LITTLE DURING THE MORNING (BUT POSSIBLY
INCREASE SLIGHTLY IN THE MID TO LATE AFTERNOON HOURS).
IN TERMS OF PRECIPITATION POTENTIAL...THERE IS VERY LITTLE TO
SPEAK OF. THE PRIMARY AXIS OF DEEP-LAYER MOISTURE (WHICH IS NOT
VERY EXPANSIVE TO BEGIN WITH) IS SITUATED WELL BEHIND THE
LOW-LEVEL FRONT. BASED ON HRRR RUNS AND UPSTREAM CONDITIONS (FROM
RADAR AND OBSERVATIONS)...PRECIPITATION HAS BEEN LIMITED TO A
CHANCE OF SPRINKLES ACROSS CENTRAL OHIO NEAR 12Z-15Z (AND THIS MAY
NOT EVEN OCCUR).
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
BEHIND THE COLD FRONT...TEMPERATURES ARE EXPECTED TO BE NOTABLY
COLDER THROUGH THE REST OF THE WEEK. HOWEVER...THE PRIMARY FOCUS
FOR THE COLD AIR ALOFT WILL BE OVER THE NORTHEASTERN STATES...WITH
THE OHIO VALLEY ON THE SOUTHWESTERN EDGE OF THE LARGE DEVELOPING
MID-LEVEL TROUGH. AT THE SURFACE...DRY HIGH PRESSURE WILL MOVE
INTO PLACE...PROVIDING GENERALLY LIGHT WINDS...AND THUS NO REASON
FOR ANY SIGNIFICANT MODIFICATION OF THE AIR IN THE LOW-LEVELS.
THUS...THE WARMING TREND THROUGH THE END OF THE WEEK WILL BE
GENERALLY SLOW. ALTHOUGH WINDS WILL BECOME MORE FAVORABLE FOR
WARMING BY FRIDAY...CONDITIONS WILL LIKELY ALSO BE WETTER AND
CLOUDIER.
THE ONLY CONCERN FOR PRECIPITATION THROUGH THE REST OF THE WEEK
WILL BE WITH A SOUTHERN STREAM SYSTEM APPROACHING THE SOUTHERN
OHIO VALLEY ON THURSDAY. THE INITIAL SHOT OF MOISTURE WILL RIDE
INTO THE AREA ON THURSDAY MORNING...PERHAPS A SLIGHT DELAY FROM
WHAT PREVIOUS FORECASTS AND MODEL RUNS HAD INDICATED. THE BIGGEST
CONCERN WITH THE PROGRESSION OF THIS MOISTURE IS THE NORTHWARD
EXTENT...WHICH STILL REMAINS VARIABLE FROM MODEL TO MODEL. IN
GENERAL...THE ECMWF HAS ALLOWED FOR THE GREATEST NORTHWARD
PROGRESSION (COVERING A MUCH WIDER SWATH OF THE ILN FORECAST AREA)
AND THE NAM HAS BEEN FURTHEST TO THE SOUTH (LEAVING CONDITIONS
MAINLY DRY). A GFS SOLUTION IS NOT A BAD COMPROMISE...FOCUSING
PRECIPITATION MAINLY ALONG AND SOUTH OF THE OHIO RIVER WITH THE
INITIAL BATCH OF PRECIPITATION. THINGS GET SLIGHTLY MORE
COMPLICATED GOING INTO THURSDAY NIGHT...AS A SHORTWAVE IN THE
NORTHERN STREAM BEGINS TO INTERACT WITH THE SYSTEM...PIVOTING
THINGS INTO A DIRECTION OF NORTHEASTERLY TRAVEL. AS THIS
OCCURS...THE 00Z MODEL RUNS HAVE BEEN FAIRLY UNANIMOUS IN ALLOWING
FOR A MUCH HIGHER CHANCE OF PRECIPITATION IN THE SOUTHEASTERN ILN
FORECAST AREA.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
WE WILL TRANSITION INTO MORE OF A NORTHWEST FLOW PATTERN ALOFT
THROUGH THE WEEKEND. SHORT WAVE ENERGY DROPPING DOWN THROUGH THE
GREAT LAKES WILL HELP DRIVE A COLD FRONT SOUTH THROUGH OUR AREA
SATURDAY INTO SATURDAY NIGHT. IT LOOKS LIKE THE BEST FORCING AND
DEEPEST MOISTURE WILL PRIMARILY REMAIN OFF TO OUR NORTH AND
EAST...BUT WILL GO AHEAD AND INTRODUCE AT LEAST SOME SLIGHT CHANCE
POPS WITH THIS ACROSS OUR EAST THROUGH THE DAY ON SATURDAY. HIGHS
ON SATURDAY SHOULD PUSH UP INTO THE 50S AHEAD OF THE FRONT. COOL
HIGH PRESSURE WILL BUILD INTO THE AREA FOR THE FIRST PART OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 40S SUNDAY AND MONDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT WILL DROP SOUTH ACROSS THE TAF SITES EARLY THIS
MORNING. BIGGEST CONCERN ASSOCIATED WITH THE FRONT WILL BE THE
POTENTIAL FOR LOWER CEILINGS AND GUSTY NORTHERLY WINDS IN THE WAKE
OF FRONTAL PASSAGE. FEEL CONFIDENT THAT CEILINGS WILL DROP INTO
THE MVFR CATEGORY AND WILL LIKELY FALL BELOW 2000 FEET IN SPOTS.
THE EXCEPTION WOULD BE KLUK WHICH IS A LOWER ELEVATION AIRPORT.
THUS...WILL FORECAST A PERIOD OF MVFR CEILINGS THIS MORNING INTO
EARLY AFTERNOON. DRIER AIR FILTERING SOUTHWARD IN THE LATER PART
OF THE AFTERNOON WILL ALLOW CEILINGS TO SCATTERED AND RETURN TO
VFR. GUSTY NORTHERLY WINDS OF 12-16 KNOTS WITH GUSTS AROUND 25
KNOTS CAN BE EXPECTED.
FOR TONIGHT...AN EXPANSIVE SURFACE RIDGE OF HIGH PRESSURE WILL
BUILD SOUTHEAST INTO THE OHIO VALLEY. A RELAXING PRESSURE GRADIENT
AND NIGHTFALL DECOUPLING WILL ALLOW WINDS TO DIMINISH OVER TIME.
SOME HIGHER LEVEL CLOUDS ARE FORECAST TO SPILL EAST/SOUTHEAST
INTO THE REGION AFTER 06Z.
OUTLOOK...MVFR CEILINGS AND VISIBILITIES POSSIBLE THURSDAY NIGHT
INTO FRIDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...JGL
AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
352 AM EDT TUE MAR 17 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE SOUTH ACROSS THE REGION THIS MORNING...WITH
MUCH COOLER AND DRIER AIR SETTLING IN BEHIND IT. A CHANCE OF RAIN
WILL OCCUR ON THURSDAY INTO FRIDAY...WITH DRY CONDITIONS AND
SLIGHTLY WARMER TEMPERATURES FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE ILN CWA WILL SPEND ANOTHER FEW HOURS IN A WARM AIR MASS AHEAD
OF AN APPROACHING COLD FRONT...BEFORE THIS BRIEF PERIOD OF
WELL-ABOVE-NORMAL TEMPERATURES COMES TO AN END. THE SURFACE COLD
FRONT CURRENTLY EXTENDS FROM AROUND FORT WAYNE TO TOLEDO.
HOWEVER...BASED ON THETA-E AND WIND PLOTS AT VARIOUS LEVELS ON
RECENT NAM/RAP RUNS...THE FRONT IS THE MOST WELL-DEFINED AT 925MB.
UNTIL THE FRONT ARRIVES...TEMPERATURES WILL CONTINUE TO SHOW
ALMOST NO DECREASE...WITH GUSTY WSW FLOW.
THE TEMPERATURE FORECAST FOR TODAY IS A CHALLENGE...BECAUSE THE
FRONT WILL BE COMING THROUGH THE REGION DURING THE TYPICAL TIME
PERIOD OF THE LARGEST DIURNAL SWINGS...BUT WILL BE CLEAR THROUGH
THE AREA BEFORE THE END OF THE AFTERNOON. IT IS OBVIOUS THAT THERE
WILL NOT BE A TYPICAL DIURNAL TRACE FOR TEMPERATURES...BUT THIS
ALSO DOES NOT LOOK LIKE A SITUATION WITH STEADILY FALLING
TEMPERATURES THROUGH THE DAY. RATHER THAN A CURVE...THE
TEMPERATURE TRACE TODAY MAY END UP LIKE MORE OF A ZIG-ZAG...WITH
VALUES THAT MOVE VERY LITTLE DURING THE MORNING (BUT POSSIBLY
INCREASE SLIGHTLY IN THE MID TO LATE AFTERNOON HOURS).
IN TERMS OF PRECIPITATION POTENTIAL...THERE IS VERY LITTLE TO
SPEAK OF. THE PRIMARY AXIS OF DEEP-LAYER MOISTURE (WHICH IS NOT
VERY EXPANSIVE TO BEGIN WITH) IS SITUATED WELL BEHIND THE
LOW-LEVEL FRONT. BASED ON HRRR RUNS AND UPSTREAM CONDITIONS (FROM
RADAR AND OBSERVATIONS)...PRECIPITATION HAS BEEN LIMITED TO A
CHANCE OF SPRINKLES ACROSS CENTRAL OHIO NEAR 12Z-15Z (AND THIS MAY
NOT EVEN OCCUR).
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
BEHIND THE COLD FRONT...TEMPERATURES ARE EXPECTED TO BE NOTABLY
COLDER THROUGH THE REST OF THE WEEK. HOWEVER...THE PRIMARY FOCUS
FOR THE COLD AIR ALOFT WILL BE OVER THE NORTHEASTERN STATES...WITH
THE OHIO VALLEY ON THE SOUTHWESTERN EDGE OF THE LARGE DEVELOPING
MID-LEVEL TROUGH. AT THE SURFACE...DRY HIGH PRESSURE WILL MOVE
INTO PLACE...PROVIDING GENERALLY LIGHT WINDS...AND THUS NO REASON
FOR ANY SIGNIFICANT MODIFICATION OF THE AIR IN THE LOW-LEVELS.
THUS...THE WARMING TREND THROUGH THE END OF THE WEEK WILL BE
GENERALLY SLOW. ALTHOUGH WINDS WILL BECOME MORE FAVORABLE FOR
WARMING BY FRIDAY...CONDITIONS WILL LIKELY ALSO BE WETTER AND
CLOUDIER.
THE ONLY CONCERN FOR PRECIPITATION THROUGH THE REST OF THE WEEK
WILL BE WITH A SOUTHERN STREAM SYSTEM APPROACHING THE SOUTHERN
OHIO VALLEY ON THURSDAY. THE INITIAL SHOT OF MOISTURE WILL RIDE
INTO THE AREA ON THURSDAY MORNING...PERHAPS A SLIGHT DELAY FROM
WHAT PREVIOUS FORECASTS AND MODEL RUNS HAD INDICATED. THE BIGGEST
CONCERN WITH THE PROGRESSION OF THIS MOISTURE IS THE NORTHWARD
EXTENT...WHICH STILL REMAINS VARIABLE FROM MODEL TO MODEL. IN
GENERAL...THE ECMWF HAS ALLOWED FOR THE GREATEST NORTHWARD
PROGRESSION (COVERING A MUCH WIDER SWATH OF THE ILN FORECAST AREA)
AND THE NAM HAS BEEN FURTHEST TO THE SOUTH (LEAVING CONDITIONS
MAINLY DRY). A GFS SOLUTION IS NOT A BAD COMPROMISE...FOCUSING
PRECIPITATION MAINLY ALONG AND SOUTH OF THE OHIO RIVER WITH THE
INITIAL BATCH OF PRECIPITATION. THINGS GET SLIGHTLY MORE
COMPLICATED GOING INTO THURSDAY NIGHT...AS A SHORTWAVE IN THE
NORTHERN STREAM BEGINS TO INTERACT WITH THE SYSTEM...PIVOTING
THINGS INTO A DIRECTION OF NORTHEASTERLY TRAVEL. AS THIS
OCCURS...THE 00Z MODEL RUNS HAVE BEEN FAIRLY UNANIMOUS IN ALLOWING
FOR A MUCH HIGHER CHANCE OF PRECIPITATION IN THE SOUTHEASTERN ILN
FORECAST AREA.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
WE WILL TRANSITION INTO MORE OF A NORTHWEST FLOW PATTERN ALOFT
THROUGH THE WEEKEND. SHORT WAVE ENERGY DROPPING DOWN THROUGH THE
GREAT LAKES WILL HELP DRIVE A COLD FRONT SOUTH THROUGH OUR AREA
SATURDAY INTO SATURDAY NIGHT. IT LOOKS LIKE THE BEST FORCING AND
DEEPEST MOISTURE WILL PRIMARILY REMAIN OFF TO OUR NORTH AND
EAST...BUT WILL GO AHEAD AND INTRODUCE AT LEAST SOME SLIGHT CHANCE
POPS WITH THIS ACROSS OUR EAST THROUGH THE DAY ON SATURDAY. HIGHS
ON SATURDAY SHOULD PUSH UP INTO THE 50S AHEAD OF THE FRONT. COOL
HIGH PRESSURE WILL BUILD INTO THE AREA FOR THE FIRST PART OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 40S SUNDAY AND MONDAY.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT WILL DROP SOUTH ACROSS THE TAF SITES BETWEEN 11Z AND
13Z. IN TERMS OF PRECIPITATION...LITTLE IF ANY IS EXPECTED.
BIGGEST CONCERN ASSOCIATED WITH THE FRONT WILL BE THE POTENTIAL
FOR LOWER CEILINGS AND GUSTY NORTHERLY WINDS IN THE WAKE OF
FRONTAL PASSAGE. MODELS CONTINUE TO INDICATE THAT PERHAPS
CEILINGS MAY DEVELOP AS LOW AS IFR. I AM NOT CONFIDENT ON THIS
GIVEN THE PAST HISTORY OF THE MODELS OVERDOING THE LOW LEVEL
RELATIVE HUMIDITY FIELDS. FEEL MORE CONFIDENT THAT CEILINGS WILL
DROP INTO THE MVFR CATEGORY AND WILL LIKELY FALL BELOW 2000
FEET. THE EXCEPTION WOULD BE KLUK WHICH IS A LOWER ELEVATION AIRPORT.
THUS...WILL FORECAST A PERIOD OF MVFR CEILINGS THIS MORNING INTO
EARLY AFTERNOON. DRIER AIR FILTERING SOUTHWARD IN THE LATER PART
OF THE AFTERNOON SHOULD ALLOW CEILINGS TO SCATTERED AND RETURN TO
VFR. GUSTY NORTHERLY WINDS OF 12-15 KNOTS WITH GUSTS AROUND 25
KNOTS CAN BE EXPECTED.
FOR TONIGHT...AN EXPANSIVE SURFACE RIDGE OF HIGH PRESSURE WILL
BUILD SOUTHEAST INTO THE OHIO VALLEY. A RELAXING PRESSURE GRADIENT
AND NIGHTFALL DECOUPLING WILL ALLOW WINDS TO DIMINISH OVER TIME.
SOME HIGHER LEVEL CLOUDS MAY SPILL EAST/SOUTHEAST INTO THE REGION
AFTER 06Z.
OUTLOOK...NO SIGNIFICANT WEATHER IS EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HATZOS
NEAR TERM...HATZOS
SHORT TERM...HATZOS
LONG TERM...JGL
AVIATION...HICKMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
111 AM EDT TUE MAR 17 2015
.SYNOPSIS...
WEAK LOW PRESSURE WILL MOVE EAST ACROSS THE SOUTHERN GREAT LAKES
THIS EVENING AND REACH NEW ENGLAND TUESDAY. A COLD FRONT TRAILING
THE LOW WILL DROP ACROSS THE AREA OVERNIGHT. HIGH PRESSURE WILL
BEGIN TO BUILD INTO THE AREA TUESDAY AFTERNOON. THIS AREA OF HIGH
PRESSURE WILL CONTROL THE WEATHER INTO THURSDAY.
&&
.NEAR TERM /THROUGH TODAY/...
MID LEVEL CLOUDS REMAIN OVER THE ENTIRE AREA. LITTLE IF ANY PRECIP
IS FALLING ACROSS THE AREA. THE NEW GUIDANCE COMING IN HAS REALLY
BACKED OFF ON PRECIP CHANCES OVERNIGHT AND TUESDAY MORNING. WILL
LIMIT THE MENTION OVERNIGHT TO FAR NE OH AND NW PA. EVEN THERE
HAVE LOWERED CHANCES SLIGHTLY. LOCATIONS FURTHER SOUTH AND WEST
WILL LIKELY SEE NO MORE THAN A FEW SPRINKLES. BOTH THE LATEST HRRR
AND RUC SHOW LITTLE IF ANY MEASURABLE PRECIP OVERNIGHT. HAVE NUDGE
TEMPS UP SLIGHTLY.
CLOUDS CONTINUE TO THICKEN ACROSS THE AREA AS ISENTROPIC LIFT
INCREASE AHEAD OF LOW PRESSURE APPROACHING FROM THE WEST. RADAR
SHOWING PRECIP DEVELOPING AS WELL. INITIALLY BELIEVE MUCH OF THIS
IS ALOFT BUT EVENTUALLY LATE THIS AFTERNOON OR THIS EVENING
EXPECT LIGHT RAIN WILL DEVELOP. BEST CHANCES ACROSS NERN OHIO AND
NWRN PA. WILL HAVE SLIGHT CHANCE POPS FROM CLEVELAND TO YOUNGSTOWN
AND CHANCE NORTHEAST OF THAT LINE. THROUGH LATE EVENING AM
EXPECTING A BREAK IN PRECIP AS BEST LIFT MOVES EAST AND WHILE COLD
FRONT IS STILL TO OUR NORTH. AFTER MIDNIGHT HOWEVER COLD FRONT
MOVES THROUGH WITH RAIN SHOWERS BEHIND THE FRONT. BEST CHANCE
AGAIN NORTHEAST OHIO AND NWRN PA WHERE BEST MOISTURE WILL BE. WILL
WORK UP TO LIKELY POPS FOR A COUPLE HOURS NWRN PA LATE WHILE
CHANCE OR SLIGHT CHANCE SHOULD BE GOOD ACROSS THE REMAINDER OF THE
AREA. TEMP TRENDS OVERNIGHT WILL BE MORE TRICKY THAN THE ACTUAL
LOWS WITH EVENING TEMPS DROPPING OFF SLOWLY IN THE WARM ADVECTION
AND INCREASING CLOUDS. AFTER MIDNIGHT TEMPS SHOULD THEN DROP OFF
BEHIND THE FRONT.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
FOLLOWED SREF IN THE NEAR TERM FOR TIMING OF MOISTURE AND THE COLD
FRONT. BY 12Z TUESDAY THE COLD FRONT WILL BE NEAR THE OHIO RIVER
WITH THE AXIS OF BEST MOISTURE ACROSS THE AREA FROM EAST TO WEST.
WILL BEGIN THE DAY WITH CHANCE OR SLIGHT CHANCE POPS ACROSS NRN
OHIO. WILL GO WITH LIKELY IN NWRN PA FOR AN HOUR OR TWO. POPS WILL
DROP QUICKLY AS DRIER AIR MOVES IN BEHIND THE FRONT. WITH THE LAKE
STILL MOSTLY FROZEN NOT EXPECTING TOO MUCH IN THE WAY OF CLOUDS OR
PRECIP OFF THE LAKE IN THE COLD ADVECTION. SO WILL ALLOW CLOUDS TO
BREAK/THIN AND MOVE SOUTH THROUGH THE DAY WITH THE BUILDING HIGH
PRESSURE AND DRY AIR. MODELS BRING A LITTLE MOISTURE INTO NWRN PA
TUESDAY NIGHT AND WHILE STILL NOT EXPECTING MUCH WILL HAVE A
SLIGHT CHANCE POP WITH LIGHT SNOW IN THE GRAPHICS. OTHERWISE HIGH
PRESSURE BUILDS IN THROUGH WEDNESDAY NIGHT SO EXPECT DRY AND COOL.
THURSDAY MOISTURE WILL BE POOLING ACROSS THE SOUTHERN STATES IN
DECENT OVERRUNNING. MODELS SUGGEST MOISTURE REACHES INTO THE AREA
BUT NOT BEFORE LATE THURSDAY NIGHT OR FRIDAY. TEMPS NEAR TO BELOW
NORMAL.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
THE LONG TERM FORECAST WILL BEGIN WITH NEAR NORMAL TEMPERATURES ON
FRIDAY...FALLING BELOW NORMAL BY SUNDAY WITH THE PASSAGE OF THE NEXT
STRONG COLD FRONT. FRIDAY SHOULD BE MOSTLY DRY WITH WEAK WARM
ADVECTION. WE ARE WATCHING MOISTURE MOVING THROUGH THE OHIO VALLEY
WHICH SHOULD MOSTLY REMAIN TO THE SOUTH BUT COULD SNEAK A STRAY
SHOWER INTO NORTHWEST PENNSYLVANIA.
BY THIS WEEKEND...AN UPPER LEVEL TROUGH WILL DEVELOP OVER EASTERN
CANADA. A LOW PRESSURE SYSTEM WILL PASS NORTH OF THE GREAT LAKES ON
FRIDAY NIGHT WITH THE ASSOCIATED COLD FRONT PUSHING SOUTH ACROSS THE
AREA LATE SATURDAY INTO SATURDAY NIGHT. MODELS CONTINUE TO HAVE SOME
DIFFERENCES IN FRONTAL TIMING WHICH WILL HAVE AN EFFECT ON HIGHS ON
SATURDAY. SOUTHERN PORTIONS OF THE AREA MAY APPROACH 50 DEGREES
WHILE NORTHERN LOCATIONS REACH HIGHS EARLIER IN THE DAY AND THEN
START TO FALL. THIS SYSTEM WILL HAVE LIMITED MOISTURE SO THE 20-30
PERCENT CHANCE OF SHOWERS IN THE FORECAST IS GOOD FOR NOW.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
COLD FRONT ACROSS SE LOWER MICHIGAN WILL PUSH ACROSS THE AREA
OVERNIGHT. BEHIND THE FRONT WINDS NW-N AT 15G25KT WITH MVFR CIGS
AND PATCHY IFR CIGS. PRECIP WISE DO NOT EXPECT MUCH MORE THAN
SPRINKLES. EXPECT CONDITIONS TO IMPROVE TO VFR EXCEPT IN EXTREME
EAST BY THIS EVENING.
.OUTLOOK...NON VFR MAY LINGER EXTREME NE OH/NW PA TONIGHT AND
WEDNESDAY. NON VFR POSSIBLE THURSDAY NIGHT/FRIDAY AND AGAIN ON
SATURDAY WITH A COLD FRONT.
&&
.MARINE...
NO GALE FORCE WINDS EXPECTED THROUGH THE FORECAST PERIOD. A WAVE OF
LOW PRESSURE WILL SLIDE EAST ACROSS LAKE ERIE THIS EVENING AND PULL
A COLD FRONT SOUTH ACROSS THE AREA. WESTERLY WINDS OF 10-15 KNOTS
WILL SHIFT TO THE NORTHWEST OVERNIGHT AND INCREASE TO NEAR 20 KNOTS.
HIGH PRESSURE WILL BUILD FROM THE NORTHERN PLAINS TO THE OHIO VALLEY
FROM TUESDAY NIGHT THROUGH WEDNESDAY...THEN LINGER OVER THE EASTERN
GREAT LAKES ON THURSDAY. LOW PRESSURE WILL PASS NORTH OF THE GREAT
LAKES ON SATURDAY...PUSHING A STRONG COLD FRONT SOUTH ACROSS THE
AREA SATURDAY NIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...TK/KUBINA
SHORT TERM...TK
LONG TERM...KEC
AVIATION...DJB
MARINE...KEC
AREA FORECAST DISCUSSION
NWS NORMAN OK
633 AM CDT TUE MAR 17 2015
.DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
&&
.AVIATION...
FOR THE MOST PART...THINK VFR CONDITIONS WILL PREVAIL.
A COLD FRONT WILL CONTINUE TO PUSH SOUTH AND BE NEAR KSPS-KADH
BY 15Z...BRINGING INCREASING NORTH TO NORTHEAST WINDS. STRONGEST
WINDS WILL BE OVER PARTS OF WESTERN AND NORTHERN OKLAHOMA. THESE
WILL WILL WEAKEN AFTER 00Z.
MVFR CEILINGS MAY BE NEAR KWWR AND KGAG THROUGH 16Z. ADDED A TEMPO
MENTION AT THESE SITES DUE TO MODERATE CONFIDENCE OF OCCURRENCE.
ADDITIONAL MVFR TO PERHAPS IFR CONDITIONS WITH RA AND BR WILL
DEVELOP SOUTH OF KHBR-KSWO AFTER 03Z.
MBS
&&
.PREV DISCUSSION... /ISSUED 337 AM CDT TUE MAR 17 2015/
DISCUSSION...
TWO CONCERNS THIS MORNING... FIRST REMAINS FIRE WEATHER FOR ONGOING
CONTAINMENT OF BOILING SPRINGS FIRE IN NORTHERN WOODWARD COUNTY.
SECOND... RAIN CHANCES INCREASING TONIGHT INTO WEDNESDAY.
THIS MORNING... THE COLD FRONT STARTED TO PUSH INTO FAR NWRN OK THIS
MORNING AROUND 2-230AM CDT. THROUGH 3AM THE LEADING EDGE OF THE WIND
SHIFT HAS JUST CLEARED THE BOILING SPRINGS FIRE LOCATION. AS THE
WINDS SHIFTED AND MIXING INCREASED... IT WAS EVIDENT FROM IR SAT AND
RADAR THAT THE FIRE FLARED UP FOR ABOUT A HALF AN HOUR... SMOKE
PLUME ON RADAR QUICKLY DISAPPEARED AS CREWS GOT IT BACK UNDER
CONTROL. BIG CHALLENGE THROUGH SUNRISE WILL BE WIND SPEEDS. UP
STREAM... WINDS BEHIND THE FRONT ACROSS SERN KS HAVE REMAINED
GUSTY... SUSTAINED 20 TO 25 GUSTING 35 TO 40 MPH. THE RAP AND HRRR
HAVE DONE A DECENT JOB WITH WINDS THIS AM... CHECKING SOUNDINGS...
LOOKS LIKE ENOUGH MIXING ACROSS NWRN OK TO GET N/NE WINDS SUSTAINED
15 TO 20 GUSTING 25 TO 30 MPH. WINDS WILL RELAX ONLY SLIGHTLY AFTER
SUNRISE... REMAINING BREEZY AND OUT OF THE NW THROUGH THE AFTN. RH
VALUES WILL BE BETTER FOR FIRE WEATHER CONDITIONS... WITH MINIMUMS
IN THE MID 30S IN NWRN OK AND 40S TO 50S ACROSS THE REST OF OK INTO
NRN TX.
AS FOR RAIN... MADE ONLY MINOR ADJUSTMENTS THIS MORNING. INCREASED
POPS THIS EVENING... ESPECIALLY AFTER 18/00Z (7 PM CDT). A
FASCINATING SYSTEM... WHICH HAS REMAINED PARKED OVER WRN MX/SRN BAJA
THE PAST FEW DAYS... IT IS BRINGING SOME IMPRESSIVE MOISTURE WITH IT
INTO THE REGION. WATCHING WV THIS MORNING... THE H500 LOW LOOKS TO
FINALLY BE ON THE MOVE... SLOWLY STARTING TO LIFT NORTHWARD INTO
NWRN MEXICO. ACROSS THE PERMIAN BASIN... PWATS FROM 17/00Z SOUNDINGS
LAST NIGHT ARE ALL IN THE 99TH PERCENTILE... WITH NEAR 1.00 IN OF
PRECIPITABLE WATER ALREADY. AS THE TROUGH LIFTS INTO THE UPPER RIO
GRANDE VALLEY/TRANS PECOS REGION THIS EVENING... THE SFC TROUGH WILL
SLOWLY LIFT INTO NRN TX WITH THE CHANCE FOR RAIN INCREASING
OVERNIGHT AND SPREADING N/NE ACROSS THE REGION THROUGH SUNRISE WED.
WELL SATURATED COLUMNS AND GOOD LOW/MID LEVEL ASCENT SHOULD COMBINE
TO MAKE THIS AN EFFICIENT RAIN PRODUCER FOR MOST OF THE REGION.
INSTABILITY REMAINS PALTRY AND CONFINED TO THE RED RIVER REGION...
ALSO LAPSE RATES ARE LESS THAN STELLAR... SO MAY BE SOME ISOLATED
THUNDER ACROSS TEXOMA LATE TUE/EARLY WED AND AGAIN WED AFTN. NO
SEVERE STORMS.
MADE ONLY MINOR ADJUSTMENTS TO RAINFALL TOTALS THROUGH WED. STILL
ANTICIPATE ANYWHERE FROM A TRACE TO 0.25IN IN NRN OK... FROM 0.10 TO
0.30 ACROSS SWRN OK AND WRN N TX... WITH HIGHER TOTALS EAST AND
SOUTH OF I-44... ANYWHERE FROM A HALF TO 1 INCH OF RAIN.
EXPECT A LULL LATE WED/EARLY THU... WITH RAIN CHANCES STEADILY
INCREASING ONCE AGAIN THROUGH THU... PRIMARILY ACROSS NRN OK AS
ANOTHER COLD FRONT NUDGES SOUTH ACROSS THE SRN PLAINS AS OUR NEXT
H500 TROUGH MOVES INTO THE SW U.S. ADDITIONAL RAINFALL OF UP TO A
HALF INCH IN FAR NWRN OK TO A QUARTER OF AN INCH ACROSS THE
REMAINDER OF OK AND NRN TX IS POSSIBLE THU INTO FRI AM.
THE WEEKEND IS LOOKING DRY AND WARM... WITH HIGHS IN THE 60S TO 70S.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 63 45 57 44 / 10 100 70 30
HOBART OK 63 42 59 44 / 10 70 20 20
WICHITA FALLS TX 71 48 63 47 / 20 90 20 10
GAGE OK 54 36 60 38 / 10 30 20 30
PONCA CITY OK 61 42 50 38 / 10 70 90 30
DURANT OK 77 54 61 49 / 20 90 80 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
04/04/17
AREA FORECAST DISCUSSION
NWS NORMAN OK
337 AM CDT TUE MAR 17 2015
.DISCUSSION...
TWO CONCERNS THIS MORNING... FIRST REMAINS FIRE WEATHER FOR ONGOING
CONTAINMENT OF BOILING SPRINGS FIRE IN NORTHERN WOODWARD COUNTY.
SECOND... RAIN CHANCES INCREASING TONIGHT INTO WEDNESDAY.
THIS MORNING... THE COLD FRONT STARTED TO PUSH INTO FAR NWRN OK THIS
MORNING AROUND 2-230AM CDT. THROUGH 3AM THE LEADING EDGE OF THE WIND
SHIFT HAS JUST CLEARED THE BOILING SPRINGS FIRE LOCATION. AS THE
WINDS SHIFTED AND MIXING INCREASED... IT WAS EVIDENT FROM IR SAT AND
RADAR THAT THE FIRE FLARED UP FOR ABOUT A HALF AN HOUR... SMOKE
PLUME ON RADAR QUICKLY DISAPPEARED AS CREWS GOT IT BACK UNDER
CONTROL. BIG CHALLENGE THROUGH SUNRISE WILL BE WIND SPEEDS. UP
STREAM... WINDS BEHIND THE FRONT ACROSS SERN KS HAVE REMAINED
GUSTY... SUSTAINED 20 TO 25 GUSTING 35 TO 40 MPH. THE RAP AND HRRR
HAVE DONE A DECENT JOB WITH WINDS THIS AM... CHECKING SOUNDINGS...
LOOKS LIKE ENOUGH MIXING ACROSS NWRN OK TO GET N/NE WINDS SUSTAINED
15 TO 20 GUSTING 25 TO 30 MPH. WINDS WILL RELAX ONLY SLIGHTLY AFTER
SUNRISE... REMAINING BREEZY AND OUT OF THE NW THROUGH THE AFTN. RH
VALUES WILL BE BETTER FOR FIRE WEATHER CONDITIONS... WITH MINIMUMS
IN THE MID 30S IN NWRN OK AND 40S TO 50S ACROSS THE REST OF OK INTO
NRN TX.
AS FOR RAIN... MADE ONLY MINOR ADJUSTMENTS THIS MORNING. INCREASED
POPS THIS EVENING... ESPECIALLY AFTER 18/00Z (7 PM CDT). A
FASCINATING SYSTEM... WHICH HAS REMAINED PARKED OVER WRN MX/SRN BAJA
THE PAST FEW DAYS... IT IS BRINGING SOME IMPRESSIVE MOISTURE WITH IT
INTO THE REGION. WATCHING WV THIS MORNING... THE H500 LOW LOOKS TO
FINALLY BE ON THE MOVE... SLOWLY STARTING TO LIFT NORTHWARD INTO
NWRN MEXICO. ACROSS THE PERMIAN BASIN... PWATS FROM 17/00Z SOUNDINGS
LAST NIGHT ARE ALL IN THE 99TH PERCENTILE... WITH NEAR 1.00 IN OF
PRECIPITABLE WATER ALREADY. AS THE TROUGH LIFTS INTO THE UPPER RIO
GRANDE VALLEY/TRANS PECOS REGION THIS EVENING... THE SFC TROUGH WILL
SLOWLY LIFT INTO NRN TX WITH THE CHANCE FOR RAIN INCREASING
OVERNIGHT AND SPREADING N/NE ACROSS THE REGION THROUGH SUNRISE WED.
WELL SATURATED COLUMNS AND GOOD LOW/MID LEVEL ASCENT SHOULD COMBINE
TO MAKE THIS AN EFFICIENT RAIN PRODUCER FOR MOST OF THE REGION.
INSTABILITY REMAINS PALTRY AND CONFINED TO THE RED RIVER REGION...
ALSO LAPSE RATES ARE LESS THAN STELLAR... SO MAY BE SOME ISOLATED
THUNDER ACROSS TEXOMA LATE TUE/EARLY WED AND AGAIN WED AFTN. NO
SEVERE STORMS.
MADE ONLY MINOR ADJUSTMENTS TO RAINFALL TOTALS THROUGH WED. STILL
ANTICIPATE ANYWHERE FROM A TRACE TO 0.25IN IN NRN OK... FROM 0.10 TO
0.30 ACROSS SWRN OK AND WRN N TX... WITH HIGHER TOTALS EAST AND
SOUTH OF I-44... ANYWHERE FROM A HALF TO 1 INCH OF RAIN.
EXPECT A LULL LATE WED/EARLY THU... WITH RAIN CHANCES STEADILY
INCREASING ONCE AGAIN THROUGH THU... PRIMARILY ACROSS NRN OK AS
ANOTHER COLD FRONT NUDGES SOUTH ACROSS THE SRN PLAINS AS OUR NEXT
H500 TROUGH MOVES INTO THE SW U.S. ADDITIONAL RAINFALL OF UP TO A
HALF INCH IN FAR NWRN OK TO A QUARTER OF AN INCH ACROSS THE
REMAINDER OF OK AND NRN TX IS POSSIBLE THU INTO FRI AM.
THE WEEKEND IS LOOKING DRY AND WARM... WITH HIGHS IN THE 60S TO 70S.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 63 45 57 44 / 10 100 70 30
HOBART OK 63 42 59 44 / 10 70 20 20
WICHITA FALLS TX 71 48 63 47 / 20 90 20 10
GAGE OK 54 36 60 38 / 10 30 20 30
PONCA CITY OK 61 42 50 38 / 10 70 90 30
DURANT OK 77 54 61 49 / 20 90 80 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
611 AM EDT TUE MAR 17 2015
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS MORNING.
HIGH PRESSURE WILL THEN BUILD ACROSS THE AREA FOR MID WEEK. AN
AREA OF LOW PRESSURE WILL TRACK SOUTH OF PENNSYLVANIA ON
FRIDAY...FOLLOWED BY A STRONG COLD FRONT ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REGIONAL RADAR MOSAIC AT 09Z SHOWS AN AREA OF RAIN ACROSS
NORTHERN PA IN ASSOC WITH ISENTROPIC LIFT AT NOSE OF LL JET.
LATEST 4KM NAM AND HRRR INDICATE THIS AREA OF RAIN RAPIDLY SHIFTS
EAST OF THE AREA BY 12Z WITH PASSAGE OF LL JET. TRAILING COLD
FRONT...ENTERING NW PA AT 09Z...WILL PUSH SE ACROSS THE AREA LATER THIS
MORNING...EXITING THE SE COUNTIES BY NOON.
SCT SHRA SHOULD ACCOMPANY THE FROPA BTWN 12Z-16Z...WITH
MEASURABLE AMTS CONFINED MAINLY TO THE NORTHERN MTNS AND LAUREL
HIGHLANDS. MDL SOUNDINGS BECOME COLD ENOUGH FOR SNOW SHOWERS
ACROSS THE N MTNS BY ARND 15Z. HOWEVER...QPF SO LGT AND SFC TEMPS
MARGINAL...SO NO ACCUMS EXPECTED.
TODAY WILL BE A BREEZY DAY...AS STRONGER WINDS ALOFT BEGIN MIXING
TO THE SFC IN WAKE OF CDFRONT. BUFKIT SOUNDINGS SUPPORT
WIDESPREAD GUSTS TO ARND 30KTS FROM LATE AM THRU EARLY EVENING.
STRONG COLD ADVECTION SHOULD REVERSE THE NORMAL DIURNAL TEMP
TREND...WITH STEADY OR SLOWLY FALLING TEMPS ACROSS MOST OF THE
AREA FROM LATE MORNING ONWARD. AFTER A MILD START...READINGS BY
DUSK SHOULD RANGE FROM THE U20S OVR THE N MTNS...TO THE L40S
ACROSS THE LOWER SUSQ VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
HIGH PRES AND ASSOC LOW PWAT AIR MASS WILL BUILD INTO THE AREA
TONIGHT AND WEDNESDAY...BRINGING FAIR BUT CHILLY WX. IT WILL FEEL
LIKE MID WINTER AGAIN TONIGHT...AS TEMPS FALL INTO THE UTEENS AND
L20S. AN ACCOMPANYING NWRLY BREEZE WILL CREATE WCHILLS IN THE
SINGLE DIGITS AND TEENS.
LG SCALE SUBSIDENCE...COMBINED WITH MOSTLY FROZEN LKS ERIE AND
HURON...SHOULD RESULT IN A MOSTLY SUNNY WEDNESDAY. ENS MEAN 8H
TEMPS BTWN -8C AND -10C SHOULD TRANSLATE TO MAX TEMPS FROM THE
L30S NW MTNS...TO THE L/M40S IN THE SOUTHERN VALLEYS. DEEPENING
BLYR DEPTH SHOULD MIX DOWN SOME FAIRLY GUSTY WINDS BY AFTN OF ARND
25KTS...ADDING TO THE CHILL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
FAIR WX...LGT WIND AND STILL COOL CONDS EXPECTED THURSDAY...AS
SFC HIGH PASSES OVR PA. BULK OF MED RANGE GUIDANCE NOW SUPPORTING
THE LIKELIHOOD OF SNOW ACROSS SOUTHERN PA FRIDAY...AS SOUTHERN
STREAM SHORTWAVE LIFTS THRU THE REGION. GEFS/ECENS BOTH INDICATE
SFC LOW REMAINS WEAK AS IT TRACKS SOUTH OF THE MASON DIXON LINE.
HOWEVER...COMBINATION OF WEAK SFC LOW AND HIGH OFF THE NEW ENG
COAST...SHOULD CREATE ENOUGH SOUTHERLY FLOW/OVERRUNNING FOR A
LIGHT TO MOD PRECIP EVENT. ATTM...GEFS PLUMES AND MEAN 8H 0C
ISOTHERM IN ECENS SUGGEST MOST LIKELY PTYPE IS SNOW. ALTHOUGH
SOME RAIN POSSIBLE ALONG THE S TIER.
A FAIR AMT OF AGREEMENT THRU NEXT WEEKEND AMONG MED RANGE
GUIDANCE...ALL OF WHICH INDICATE A DEEP TROUGH FORMING OVR THE
NORTHEAST CONUS IN RESPONSE TO BUILDING RIDGE ON THE PACIFIC
COAST. 00Z GFS/CANADIAN/ECMWF ALL INDICATE PASSAGE OF A SHARP
COLD FRONT ON SATURDAY...FOLLOWED BY WELL BLW NORMAL TEMPS
SUNDAY/MONDAY.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
SFC COLD FRONT MARCHING SOUTHEAST FROM A KELM...TO KDUJ AND KCAK
LINE AT 0930Z. AREAS OF LIGHT RAIN/SHOWERS AROUND AND TO THE SE
OF A 1001 MB SFC LOW /THAT WAS CENTERED NEAR BGM/ WILL BRUSH OUR
NORTH AND NE ZONES EARLY TODAY WITH SOME AREAS OF MVFR. ACROSS THE
WRN MTNS /TAF SITES KBFD AND KJST/ THE COOL...MOIST...UPSLOPE
NWRLY FLOW IN THE WAKE OF THE CFROPA WILL LEAD TO MVFR CIGS AND
MORE BRIEF MVFR VSBYS IN -SHRA...CHANGING TO -SHSN LATER THIS
MORNING.
GUSTY NW WINDS SIMILAR TO THIS PAST SUNDAY /ALBEIT LIKELY 5 KNOTS
OR SO LOWER/...WILL CREATE CROSS WINDS FOR TAKEOFF AND FAP AT
NUMEROUS AIRFIELDS ALONG WITH A SIGNIFICANT AMOUNT OF MECHANICAL
TURBULENCE. THE MOST PRONOUNCED WIND SHEAR LAYER TODAY INTO
TONIGHT WILL BE NEAR AND JUST ABOVE THE TOP OF THE WELL-MIXED
LAYER /OR BETWEEN 3-5 KFT GAL/. SINCE THIS SHEAR IS OCCURRING
ABOVE 2000 FT AGL...TRUE LLWS WILL NOT BE PRESENT OR INCLUDED IN
THE TAFS.
THE GUSTY NW WIND OF 25 TO 30 KTS WILL CONTINUE THROUGH TONIGHT
AND INTO WEDNESDAY WITH GENERALLY DRY CONDITIONS. CIGS WILL VARY
FROM VFR BKN-OVC THIS MORNING ACROSS CENTRAL AND ERN PENN...WITH
MVFR TO LOCAL IFR CIGS ACROSS THE NW MTNS AND LAUREL HIGHLANDS.
SKY CONDITIONS WILL IMPROVE TO MAINLY SCATTERED VFR FOR ALL AREAS
TONIGHT AND WEDNESDAY.
OUTLOOK...
WED...MVFR CIGS PSBL NW. GUSTY WINDS 20-30KTS FROM 290-320.
THU...VFR/NO SIG WX.
THU-NGT-FRI...MVFR/IFR PSBL IN RA/SN ASSOCD WITH LOW PRES TRACKING
ALONG MID-ATLC/NORTHEAST COAST.
SAT...MVFR/IFR PSBL NW 1/2 IN -SHSN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
604 AM EDT TUE MAR 17 2015
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE REGION THIS MORNING.
HIGH PRESSURE WILL THEN BUILD ACROSS THE AREA FOR MID WEEK. AN
AREA OF LOW PRESSURE WILL TRACK SOUTH OF PENNSYLVANIA ON
FRIDAY...FOLLOWED BY A STRONG COLD FRONT ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REGIONAL RADAR MOSAIC AT 09Z SHOWS AN AREA OF RAIN ACROSS
NORTHERN PA IN ASSOC WITH ISENTROPIC LIFT AT NOSE OF LL JET.
LATEST 4KM NAM AND HRRR INDICATE THIS AREA OF RAIN RAPIDLY SHIFTS
EAST OF THE AREA BY 12Z WITH PASSAGE OF LL JET. TRAILING COLD
FRONT...ENTERING NW PA AT 09Z...WILL PUSH SE ACROSS THE AREA LATER THIS
MORNING...EXITING THE SE COUNTIES BY NOON.
SCT SHRA SHOULD ACCOMPANY THE FROPA BTWN 12Z-16Z...WITH
MEASURABLE AMTS CONFINED MAINLY TO THE NORTHERN MTNS AND LAUREL
HIGHLANDS. MDL SOUNDINGS BECOME COLD ENOUGH FOR SNOW SHOWERS
ACROSS THE N MTNS BY ARND 15Z. HOWEVER...QPF SO LGT AND SFC TEMPS
MARGINAL...SO NO ACCUMS EXPECTED.
TODAY WILL BE A BREEZY DAY...AS STRONGER WINDS ALOFT BEGIN MIXING
TO THE SFC IN WAKE OF CDFRONT. BUFKIT SOUNDINGS SUPPORT
WIDESPREAD GUSTS TO ARND 30KTS FROM LATE AM THRU EARLY EVENING.
STRONG COLD ADVECTION SHOULD REVERSE THE NORMAL DIURNAL TEMP
TREND...WITH STEADY OR SLOWLY FALLING TEMPS ACROSS MOST OF THE
AREA FROM LATE MORNING ONWARD. AFTER A MILD START...READINGS BY
DUSK SHOULD RANGE FROM THE U20S OVR THE N MTNS...TO THE L40S
ACROSS THE LOWER SUSQ VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
HIGH PRES AND ASSOC LOW PWAT AIR MASS WILL BUILD INTO THE AREA
TONIGHT AND WEDNESDAY...BRINGING FAIR BUT CHILLY WX. IT WILL FEEL
LIKE MID WINTER AGAIN TONIGHT...AS TEMPS FALL INTO THE UTEENS AND
L20S. AN ACCOMPANYING NWRLY BREEZE WILL CREATE WCHILLS IN THE
SINGLE DIGITS AND TEENS.
LG SCALE SUBSIDENCE...COMBINED WITH MOSTLY FROZEN LKS ERIE AND
HURON...SHOULD RESULT IN A MOSTLY SUNNY WEDNESDAY. ENS MEAN 8H
TEMPS BTWN -8C AND -10C SHOULD TRANSLATE TO MAX TEMPS FROM THE
L30S NW MTNS...TO THE L/M40S IN THE SOUTHERN VALLEYS. DEEPENING
BLYR DEPTH SHOULD MIX DOWN SOME FAIRLY GUSTY WINDS BY AFTN OF ARND
25KTS...ADDING TO THE CHILL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
FAIR WX...LGT WIND AND STILL COOL CONDS EXPECTED THURSDAY...AS
SFC HIGH PASSES OVR PA. BULK OF MED RANGE GUIDANCE NOW SUPPORTING
THE LIKELIHOOD OF SNOW ACROSS SOUTHERN PA FRIDAY...AS SOUTHERN
STREAM SHORTWAVE LIFTS THRU THE REGION. GEFS/ECENS BOTH INDICATE
SFC LOW REMAINS WEAK AS IT TRACKS SOUTH OF THE MASON DIXON LINE.
HOWEVER...COMBINATION OF WEAK SFC LOW AND HIGH OFF THE NEW ENG
COAST...SHOULD CREATE ENOUGH SOUTHERLY FLOW/OVERRUNNING FOR A
LIGHT TO MOD PRECIP EVENT. ATTM...GEFS PLUMES AND MEAN 8H 0C
ISOTHERM IN ECENS SUGGEST MOST LIKELY PTYPE IS SNOW. ALTHOUGH
SOME RAIN POSSIBLE ALONG THE S TIER.
A FAIR AMT OF AGREEMENT THRU NEXT WEEKEND AMONG MED RANGE
GUIDANCE...ALL OF WHICH INDICATE A DEEP TROUGH FORMING OVR THE
NORTHEAST CONUS IN RESPONSE TO BUILDING RIDGE ON THE PACIFIC
COAST. 00Z GFS/CANADIAN/ECMWF ALL INDICATE PASSAGE OF A SHARP
COLD FRONT ON SATURDAY...FOLLOWED BY WELL BLW NORMAL TEMPS
SUNDAY/MONDAY.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
AREA OF LIGHT RAIN NOW EXITING THE FAR ERN AIRSPACE ATTM. STILL
EXPECT PREVAILING VFR OVERNIGHT WITH CIGS STAYING AOA 5KFT AGL IN
MOST AREAS. CALM WINDS MAY PROMOTE PERIOD OF MVFR VIS OVER THE ERN
TAFS UNTL GRADIENT FLOW PICKS UP TOWARD DAYBREAK. DO NOT EXPECT
TO SEE LOWERING CONDITIONS UNTIL CLOSER TO 12Z IN THE WEST AS
A COLD FRONT PUSHES SEWD THROUGH THE AIRSPACE. EXPECT MVFR/IFR
CONDS TO DEVELOP OVER THE WRN 1/3 TO 1/2 OF THE AIRSPACE /HIGHEST
CONFIDENCE IN REDUCTIONS AT BFD/JST IN ZOB SECTOR DUE TO
CAA AND UPSLOPE/ WITH LOW END VFR PREVAILING IN THE EASTERN SXNS.
DONT ANTICIPATE MUCH IN THE WAY OF PCPN ESPECIALLY E OF THE MTNS.
COLD AIR BEHIND THE FRONT MAY ALLOW FOR A MIX/CHANGEOVER TO -SHSN
OVER THE WRN TAFS EARLY TUESDAY. GUSTY WINDS FROM 290-320 WILL
BECOME THE MAIN ISSUE THRU TUESDAY WITH FQNT GUSTS IN THE 25 TO
35 KT RANGE. LOOK FOR CLEARING BY LATE AFTN ESP DOWNWIND OF THE
HIGHER TERRAIN. WINDS WILL REMAIN GUSTY INTO WEDNESDAY.
OUTLOOK...
WED...MVFR CIGS PSBL NW. GUSTY WINDS 20-30KTS FROM 290-320.
THU...VFR/NO SIG WX.
THU-NGT-FRI...MVFR/IFR PSBL IN RA/SN ASSOCD WITH LOW PRES TRACKING
ALONG MID-ATLC/NORTHEAST COAST.
SAT...MVFR/IFR PSBL NW 1/2 IN -SHSN.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD
LONG TERM...FITZGERALD
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
349 PM MDT TUE MAR 17 2015
.SYNOPSIS...
MOISTURE...CLOUDS AND RAIN CHANCES WILL CONTINUE TONIGHT. ON
WEDNESDAY WE WILL SEE SEASONAL TEMPERATURES WITH JUST A SLIGHT
CHANCE FOR RAIN. THEN FOR THURSDAY THROUGH SATURDAY WE WILL AGAIN
SEE A GOOD CHANCE FOR RAIN SHOWERS. THEN FOR SUNDAY AND INTO MOST
OF NEXT WEEK WE WILL SEE DRIER AND WARMER CONDITIONS.
&&
.DISCUSSION...
AS PROMISED THE SLOW MOVING UPPER LEVEL LOW TO OUR SOUTH HAS BEEN
ABLE TO PULL IN PLENTY OF MOISTURE TO WORK WITH. THE HIGHEST
PRECIPITABLE WATER VALUE FOR MARCH IS 0.99 AND ALL THE MODELS ARE
GOING FOR RIGHT NEAR ONE INCH THIS EVENING. A HIGH PW DOESN`T DO
YOU MUCH GOOD IF YOU CAN`T SQUEEZE ANY RAIN OUT OF IT. BOTH WITH
THE LOW SO NEAR AND WITH ALL THE MOISTURE IT DOES LOOK LIKE WE
WILL CONTINUE TO SEE A CHANCE FOR RAIN INTO THE EARLY PART OF
WEDNESDAY MORNING. THE HRRR IS SHOWING A BIT OF A RAMP DOWN LATER
THIS EVENING...BUT THERE WILL BE ENOUGH MOISTURE AND INSTABILITY
TO WARRANT A CONTINUATION OF OUR POPS THROUGH THE MORNING HOURS.
THEN ON WEDNESDAY AS THE FIRST LOW MOVES OFF TO OUR EAST ANOTHER
LOW WILL BE MOVING IN FROM THE WEST. THIS SECOND LOW IS SLOW SO WE
WILL SEE A BIT OF A DOWN DAY ON WEDNESDAY...BUT I CAN`T COMPLETELY
REMOVE THE CHANCE FOR PRECIPITATION ON WEDNESDAY. BY THURSDAY WE
WILL AGAIN SEE A GOOD CHANCE FOR RAIN...FIRST OUT WEST AND THEN BY
THURSDAY AFTERNOON ACROSS THE ENTIRE AREA. LIKE I SAID THIS LOW IS
MOVING VERY SLOWLY SO IT WILL CONTINUE TO GIVE US A CHANCE FOR
RAIN ON FRIDAY AND INTO MOST OF SATURDAY NOW.
FINALLY ON SUNDAY THE TROUGH WILL BE TO OUR EAST AND A FLAT UPPER
LEVEL RIDGE WILL BEGIN TO BUILD INTO THE SOUTHWEST. THEN ON MONDAY
THE GFS IS INDICATING THAT A BACK DOOR COLD FRONT WILL TRY AND
PUSH ACROSS THE AREA...BUT AS WE MOVE FURTHER FROM WINTER A WIND
SHIFT TO THE EAST MEANS LESS AND LESS ABOUT BRINGING IN COLDER AIR
AND IT IS SIMPLY A WIND SHIFT TO THE EAST...AND THIS IS THE CASE
THIS TIME AROUND. TEMPERATURES ACTUALLY MOVE HIGHER ON TUESDAY IN
THE EXTENDED GFS. LOOKING JUST BEYOND THE FORECAST...WE MAY SEE
OUR FIRST REALLY WINDY DAY OF MARCH NEXT WEDNESDAY AS A SHORT
WAVE DASHES ACROSS NORTHERN NEW MEXICO AND A NICE LEE SIDE TROUGH
GETS DEVELOPED.
&&
.AVIATION...VALID 18/00Z-19/00Z...
SHOWERS AND THUNDERSTORMS THROUGH THE DAY AND EVENING COULD CAUSE
MVFR CEILINGS AND VISIBILITY. ISOLATED IFR CONDITIONS POSSIBLE NEAR
SHOWERS AND THUNDERSTORMS...ESPECIALLY BETWEEN 20Z AND 06Z. ISOLATED
STORMS MAY PRODUCE TURBULENCE...WIND GUSTS TO 40 MPH AND SMALL HAIL.
&&
.FIRE WEATHER...
AN UPPER LEVEL LOW PRESSURE SYSTEM LOCATED IN THE BAJA REGION HAS
BEGUN ITS TRACK NORTHEAST AND HAS ALSO BEGUN TO STREAMING MOISTURE
FROM THE SOUTH INTO THE AREA. THIS WILL CONTINUE OUR CHANCES FOR
RAIN SHOWERS AND THUNDERSTORMS THROUGHOUT THE REST OF THE DAY
THROUGH SATURDAY. TODAY A WEAK COLD FRONT WILL ALSO PUSH INTO THE
REGION FROM THE NORTHEAST THIS COMBINED WITH HIGHER THAN AVERAGE
PRECIPITABLE WATER VALUES ACROSS THE AREA...WIDESPREAD RAIN AND
THUNDERSTORM COVERAGE WILL BE ENHANCED. GUSTY DOWNDRAFT WINDS TO 50
MPH...AND CLOUD TO GROUND LIGHTNING...REMAIN THE MAIN IMPACTS WITH
EXPECTED CONVECTION.
WEDNESDAY THE AREA WILL SEE SLIGHT DECREASE IN PRECIPITATION COVERAGE AS
A WEAK RIDGE MOVES INTO THE AREA. ON THURSDAY THE RIDGE IS REPLACED
BY A PACIFIC TROUGH THAT WILL STREAM BAJA MOISTURE INTO OUR AREA.
THIS WILL INCREASE PRECIPITATION CHANCES AND COVERAGE THURSDAY THROUGH
SATURDAY AFTERNOON. BY SUNDAY DRIER WEATHER TAKES OVER AS THE TROUGH
IS TO OUR EAST AND ZONAL FLOW SETS UP.
THIS AFTERNOON MIN RH WILL BE IN THE 40 TO 50 PERCENT RANGE ACROSS
THE ENTIRE AREA EXPECT FOR A FEW SPOTS IN THE SACS AND GILA
WILDERNESS WHERE MIN RH VALUES WILL BE IN THE 60S. WEDNESDAY MIN RH
VALUES WILL BE SIMILAR...40S TO 50S IN THE WESTERN AND CENTRAL FIRE
ZONES WITH MIN RH VALUES AS HIGH AS THE UPPER 60S IN THE EASTERN
FIRE WEATHER ZONES. HIGH RH VALUES WILL CONTINUE THROUGH MUCH OF THE
UPCOMING WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
EL PASO 49 70 55 72 51 / 50 20 20 10 20
SIERRA BLANCA 44 67 50 69 47 / 50 20 20 10 30
LAS CRUCES 45 69 49 70 45 / 40 20 30 20 20
ALAMOGORDO 44 69 48 72 45 / 30 20 30 20 30
CLOUDCROFT 35 50 37 50 33 / 40 30 40 30 40
TRUTH OR CONSEQUENCES 45 64 48 68 44 / 30 30 30 30 30
SILVER CITY 42 60 44 61 40 / 50 50 30 30 30
DEMING 46 70 48 70 43 / 40 30 30 20 20
LORDSBURG 45 68 46 67 42 / 40 40 30 30 30
WEST EL PASO METRO 49 70 56 71 51 / 50 20 20 10 20
DELL CITY 43 70 48 73 44 / 60 20 20 10 20
FORT HANCOCK 48 71 53 73 50 / 50 20 30 10 30
LOMA LINDA 45 64 50 66 46 / 50 20 20 10 20
FABENS 47 70 53 72 49 / 50 20 20 10 20
SANTA TERESA 46 70 52 71 47 / 50 20 20 10 20
WHITE SANDS HQ 47 69 52 69 48 / 40 20 20 20 30
JORNADA RANGE 42 70 46 71 42 / 40 20 30 20 30
HATCH 45 70 48 70 44 / 40 20 30 20 30
COLUMBUS 48 69 51 69 47 / 40 30 30 20 20
OROGRANDE 47 68 52 70 48 / 40 20 20 10 20
MAYHILL 37 57 41 59 35 / 50 30 30 30 30
MESCALERO 38 58 39 59 34 / 40 30 30 30 40
TIMBERON 37 57 41 58 36 / 50 30 30 20 30
WINSTON 41 61 44 60 38 / 50 40 30 30 30
HILLSBORO 44 66 46 65 43 / 40 30 30 30 30
SPACEPORT 44 68 44 70 40 / 30 20 30 20 30
LAKE ROBERTS 40 59 41 60 37 / 50 40 30 40 30
HURLEY 44 62 44 63 40 / 40 40 30 20 20
CLIFF 41 67 44 67 39 / 50 40 40 30 30
MULE CREEK 40 64 37 64 34 / 50 40 40 30 30
FAYWOOD 43 65 46 64 42 / 40 40 30 30 30
ANIMAS 46 69 48 68 44 / 40 40 30 30 30
HACHITA 45 70 47 69 43 / 40 40 30 20 20
ANTELOPE WELLS 45 69 46 68 42 / 30 40 40 30 30
CLOVERDALE 44 65 46 65 42 / 30 50 40 30 30
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
BRICE/PAZOS
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
346 PM CDT TUE MAR 17 2015
.DISCUSSION...
THE UPPER LEVEL LOW THAT WAS OVER THE BAJA REGION THE LAST SEVERAL
DAYS HAS FINALLY STARTED MOVING NORTHEAST...ALTHOUGH ITS TRACK SO
FAR HAS BEEN SLOWER THAN FORECAST. THE 12Z MODEL GUIDANCE HAS
CAUGHT ONTO THE SLOWER MOVEMENT...HOWEVER THE RAP OUT TO 18 HOURS
IS STILL SLOWER THAN THE CONSENSUS...SUGGESTIVE THAT THE PRIMARY
GUIDANCE MAY STILL BE STRUGGLING TO CATCH UP TO CURRENT TRENDS.
DUE TO THE SLOWER MOVEMENT...MOST OF THE REGION SAW MORE SUNSHINE
TODAY AND TEMPERATURES HAVE WARMED UP TO NEAR 80 IN MANY
LOCATIONS. MEANWHILE...A COLD FRONT IS DROPPING SOUTH INTO THE
REGION AND AT 3 PM WAS LOCATED FROM BRECKENRIDGE TO DENTON TO
BONHAM AND WAS MOVING SOUTH AT 10 MPH. THE FRONT WILL CONTINUE A
SOUTHWARD MOVEMENT THIS EVENING...BUT WILL BE SLOWING DOWN...AND
EVENTUALLY BECOME STATIONARY ACROSS THE SOUTHERN CWA TOMORROW.
WITHOUT TAKING A PEEK AT THE MODEL GUIDANCE AND JUST GOING DOWN
THE HEAVY RAINFALL RAINFALL CHECKLIST...ALL INGREDIENTS ARE
AVAILABLE FOR HEAVY RAIN TONIGHT AND TOMORROW: A SLOW MOVING
FRONT...STRONG LIFT...MOIST ADIABATIC LAPSE RATES...HIGH FREEZING
LEVEL...WEAK UNIDIRECTIONAL WIND SHEAR IN THE CLOUD LAYER...AND
UNSEASONABLY HIGH PRECIPITABLE WATER NEAR 1.5 INCHES. HOWEVER THE
MODEL GUIDANCE IS ALL CURIOUSLY LESS ENTHUSIASTIC WITH RAINFALL
PROSPECTS...COMING IN DRIER AND SHOWING JUST SCATTERED ACTIVITY
OVER THE REGION. MODEL PERFORMANCE HAS IMPROVED GREATLY OVER THE
LAST COUPLE OF DECADES...BUT 20 YEARS AGO THIS SETUP PROBABLY
WOULD HAVE RESULTED IN THE ISSUANCE OF A FLASH FLOOD WATCH JUST
BASED ON THE ANALYSIS DATA AND ANTECEDENT CONDITIONS. WHAT I
GATHER FROM THE UNANIMOUSLY DRIER MODEL DATA IS THAT BECAUSE THE
UPPER LOW IS MOVING UP FROM AN UNUSUALLY FAR SOUTHERLY TRACK IT IS
DRAGGING A SWATH OF REALLY DRY AIR OFF OF THE MEXICAN PLATEAU INTO
NORTH TEXAS. OUTSIDE OF WHERE THE DRY SLOT TRACKS...CONVECTION
WILL HAVE THE OPPORTUNITY TO PRODUCE HEAVY RAINFALL AS IT IS
LIKELY TO BECOME ORIENTED ALONG SOUTH-NORTH TRAINING BANDS. AM
STILL EXPECTING SOME LOCATIONS TO SEE LOCALLY HIGH RAINFALL
AMOUNTS OF 2+ INCHES...BUT DO EXPECT SOME AREAS MAY MISS OUT ON
SIGNIFICANT RAINFALL ALTOGETHER.
DUE TO THE SLOWER MOVEMENT OF THE UPPER LOW...HAVE LOWERED POPS
FOR TONIGHT ALONG AND EAST OF THE I-35 CORRIDOR. TO THE WEST OF
I-35...THE BEST CHANCES OF RAIN WILL BE THIS EVENING WHEN THE
STRONGER LIFT BEGINS TO ARRIVE INTO THE REGION. THIS LIFT WILL
REACH THE I-35 CORRIDOR AFTER MIDNIGHT AND CONTINUE THROUGH EARLY
MORNING WEDNESDAY. THE PRECIP WILL END FROM WEST TO EAST AS THE
AFOREMENTIONED DRY SLOT ROTATES INTO THE AREA AFTER MIDNIGHT OUT
WEST AND DURING THE EARLY-MID MORNING HOURS ALONG THE I-35
CORRIDOR. HI-RES GUIDANCE DOES SUGGEST A SOUTH-NORTH TRAINING
BAND WILL SET UP NEAR A FORT WORTH TO KILLEEN LINE AFTER MIDNIGHT
AND ONLY SLOWLY MOVE EASTWARD OVERNIGHT. OTHER GUIDANCE KEEPS
THIS BAND MORE ACROSS SOUTH CENTRAL TEXAS AND HAVE IT AFFECTING
JUST THE SOUTH CENTRAL PART OF THE CWA. EITHER WAY WE WILL HAVE
TO WATCH TRENDS EVOLVE OVERNIGHT TO DETERMINE WHERE ANY HEAVY
RAINFALL THREAT WILL MATERIALIZE.
A BAND OF RAIN AND STORMS SHOULD FILL IN ACROSS THE AREA EAST OF
I-35 DURING THE MORNING HOURS WEDNESDAY...AND SLOWLY MOVE
EAST/SOUTHEAST DURING THE DAY. HAVE INCREASED POPS FOR THIS AREA.
OTHERWISE TEMPS WEDNESDAY WILL BE COOLER IN THE WAKE OF THE RAIN
AND WEAK FRONT. MOSTLY CLOUDY WEATHER WILL PREVAIL WEDNESDAY
AFTERNOON INTO THURSDAY...AS THIS UPPER LEVEL SYSTEM WILL NOT
SCOUR OUT MUCH OF THE MOISTURE OVER THE AREA. HOWEVER LITTLE TO NO
ORGANIZED LIFT SUGGESTS KEEPING POPS LOW.
RAIN CHANCES INCREASE THURSDAY NIGHT AND FRIDAY AS FRONTOGENETIC
LIFT RAMPS UP OVER THE AREA WHEN THE OLD FRONTAL BOUNDARY BEGINS
TO INTENSIFY. THE FRONT WILL PUSH INTO SOUTH TEXAS DURING THE DAY
FRIDAY...AND SO WILL THE AXIS OF RAIN. SINCE THE UPPER TROUGH DOES
NOT CLEAR THE REGION UNTIL SATURDAY NIGHT...WILL KEEP SOME RAIN
CHANCES IN THE FORECAST FOR SOME LIGHT OVER-RUNNING ACTIVITY BEHIND
THE FRONT. OBVIOUSLY THESE RAIN CHANCES FRIDAY NIGHT AND SATURDAY
WILL BE HIGHER ACROSS THE SOUTH WITH JUST SLIGHT CHANCES NORTH OF
I-20. RAINFALL SHOULD BE FAIRLY WIDESPREAD WITH THIS SYSTEM...WITH
AVERAGE AMOUNTS FROM A QUARTER INCH NORTH TO 1 INCH SOUTH.
PREFER THE ECMWF/GEM FORECASTS WHICH CLEAR THE TROUGH AXIS THROUGH
THE REGION SATURDAY NIGHT. THE GFS RAINY SUNDAY FORECAST IS
VIEWED AS AN OUTLIER AT THIS TIME. TEMPERATURES WILL BE A LITTLE
COOLER FRIDAY AND SATURDAY BEHIND THE FRONT. EXPECT HIGHS IN THE
60S AND LOWS AROUND 50 WITH CLOUDY SKIES. TEMPS WARM SUNDAY AND
INTO MONDAY AHEAD OF THE NEXT SYSTEM. MODEL GUIDANCE HAS BEEN ALL
OVER THE PLACE WITH UPPER LEVEL WAVE ENERGY NEXT WEEK...BUT THERE
APPEARS TO BE SOME CONSENSUS ON BRINGING THE NEXT UPPER SYSTEM IN
AROUND MONDAY OR MONDAY NIGHT. WILL KEEP POPS LOW FOR NOW.
TR.92
&&
.AVIATION...
/ISSUED 1252 PM CDT TUE MAR 17 2015/
CONCERNS...TIMING OF MVFR CIGS AND PRECIPITATION ACTIVITY.
MVFR CIGS REMAIN SOUTH OF KACT...GENERALLY SOUTH OF A KLZZ TO KUTS
LINE...AT MIDDAY. HOWEVER...WE EXPECT MVFR CIGS TO DEVELOP OVER
ALL TERMINALS LATER THIS EVENING...03-05Z...AS AN UPPER LEVEL LOW
COMES OUT OF NORTH-CENTRAL MEXICO. WE EXPECT RAIN TO BEGIN BEFORE
MIDNIGHT AND CONTINUE OFF/ON THROUGH 09Z. THE 09-16Z TIME FRAME
COULD BE THE WINDOW OF GREATEST LIFT...THUS SHOWERS AND ISOLATED
THUNDERSTORMS SPREAD OVER THE REGION WITH THUNDERSTORMS FAVORING
AREAS CLOSER TO KACT THAN ACROSS THE METROPLEX. THE UPPER SYSTEM
WILL START EXITING THE REGION WEDNESDAY AFTERNOON...THUS RAIN WILL
END AND CIGS WILL BEGIN TO LIFT. EXPECTING VFR CIGS BY LATE
AFTERNOON AND CONTINUING THROUGH MID EVENING AS LEAST.
WINDS...A COLD FRONT IS POSITIONED NORTHWEST OF DFW AND IS EXPECT
TO MOVE INTO THE METROPLEX THIS EVENING...SLOW OR STALL AND THEN
WASH OUT TOMORROW. SO SOUTH WINDS WILL VEER WESTERLY THIS
AFTERNOON THEN LIGHT NORTHERLY FOR THE OVERNIGHT PERIOD. WE
EXPECT THEM TO RETURN WESTERLY ON WEDNESDAY. 75
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 58 68 61 72 58 / 60 60 20 20 60
WACO, TX 60 71 62 76 60 / 70 70 20 20 50
PARIS, TX 55 61 57 67 55 / 50 80 30 20 50
DENTON, TX 55 67 59 73 55 / 60 60 20 20 60
MCKINNEY, TX 56 66 58 71 56 / 60 70 20 20 60
DALLAS, TX 59 69 61 73 59 / 60 70 20 20 60
TERRELL, TX 60 70 61 73 59 / 50 80 20 20 50
CORSICANA, TX 61 70 60 74 61 / 50 80 30 20 50
TEMPLE, TX 61 71 62 75 61 / 70 70 20 20 40
MINERAL WELLS, TX 53 67 59 75 56 / 60 50 10 20 60
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
343 PM CDT Tue Mar 17 2015
.SHORT TERM...
(Tonight and Wednesday)
Water Vapor satellite shows the large upper level low pressure
spinning just southwest of the Texas Big Bend region late this
afternoon. Models are consistent with tracking this weakening system
into West Central Texas tonight and then away from the area on
Wednesday. Large area of mainly light rainfall continues across a
large portion of the area this afternoon, producing rainfall totals
of less than one tenth of an inch.
Models have been fairly consistent with the track of the low. This
would place the area from San Angelo south and west into a dry slot
for much of tonight and the day on Wednesday, with the better lift
to the southeast and east ahead of the low, and to the northwest in
the deformation zone. HRRR shows a large area of convection
redeveloping to the southwest, but not sure that`s going to happen
with the extensive cloud cover that extends as far south as the Rio
Grande. At this point, will assume some widespread rain for much of
West Central Texas, with a relative lull with only scattered
activity from San Angelo southwest into Ozona and Sonora.
For Wednesday, much of West Central Texas will be under the low
itself or under the upper level dry slot. Best lift will exit the
eastern counties from Brownwood to Junction during the morning
hours. Thus, best PoPs to the east will dry conditions returning for
most areas for the afternoon. May be hard pressed to get rid of
cloud cover though and expect it to take much of the day before
clouds break.
.LONG TERM...
(Wednesday night through Tuesday)
The next upper level trough will swing across the Plains Thursday,
sending a cold front south into the Big Country Thursday night, then
through the rest of the area Friday. In the meantime, an upper level
low will be located across Baja California, which is forecast to
trek across Central Texas Saturday. Ahead of this feature,
disturbances in the southwest flow aloft along with the
aforementioned cold front will result in scattered showers and
isolated thunderstorms late Thursday into Friday. High end chance
PoPs were continued for much of West Central Texas Thursday night,
with the better rain chances shifting to the southern half of the
area on Friday.
As previously mentioned, the upper level low across Baja California
will open up and move across Central Texas on Saturday. The current
forecast track of this system favors the heaviest precipitation
across our southern counties and south into Central Texas. PoPs
Friday night and Saturday will range from chance across the Big
Country to likely across the Interstate 10 corridor. Rain chances
will decrease Saturday evening as the upper level system moves east
of the region.
Highs on Thursday ahead of the front will be above normal, generally
in the upper 70s to near 80. The forecast cloud cover/precipitation
on Friday/Saturday will result in high temperatures generally in the
upper 50s to lower 60s. Expect near normal temperatures for the
first part of next week, with highs in the upper 60s to lower 70s
and overnight lows in the 40s. Models are indicating another upper
level trough swinging across the Southern Plains early next week,
possibly bringing a chance of rain to the eastern half of West
Central Texas. For now, PoPs were left out of the forecast and will
continue to monitor on future trends.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 49 67 53 76 52 / 70 30 10 20 50
San Angelo 51 70 55 80 55 / 60 20 10 20 50
Junction 53 71 58 80 59 / 60 40 10 20 50
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07/Daniels
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
329 PM CDT TUE MAR 17 2015
.SHORT TERM (TONIGHT THROUGH WEDNESDAY)...
ACTIVE AND DIFFICULT FORECAST PERIOD NEXT 24 HOURS THAT DEPENDING ON
CONVECTIVE EVOLUTION...COULD RESULT IN MINOR FLOODING IMPACTS FROM
LOCALIZED HEAVY RAINFALL.
THE WELL TALKED ABOUT CUT-OFF CLOSED MID/UPPER LEVEL LOW OVER MEXICO
CONTINUES TO ALLOW MID AND UPPER LEVEL PACIFIC MOISTURE TO STREAM
INTO THE REGION OVERTOP LOW-LEVEL GULF MOISTURE. THIS IS AIDING A
SLOWLY EASTWARD PROGRESSING LIGHT RAIN BAND ALONG AND JUST EAST OF
THE RIO GRANDE VALLEY. THE DEEP SOUTHERLY COLUMN FLOW WHICH AS
MITIGATED MUCH OF AN EASTWARD MOVEMENT SHOULD BECOME SLIGHTLY MORE
WESTERLY OVER THE NEXT 6 HOURS PER RAP/NAM OUTPUT AND SOME EVIDENCE
IN LATEST WATER VAPOR IMAGERY OF STRONGER NE FLOW ON THE BACK SIDE
OF THE CURRENT MOISTURE PLUME. THIS SHOULD HELP PUSH THE BAND EAST
BUT AS IT DOES SO IT MAY OUTPACE THE BETTER MID AND UPPER LEVEL
DIVERGENT SUPPORT AND WEAKEN. MOST HI-RES GUIDANCE HAS SHOWN THIS
WITH HRRR NOW STARTING TO FALL INTO THAT CAMP. HOWEVER...SOME WEAK
LOW-LVL INSTABILITY EXISTS FARTHER EAST AND THIS COULD BE JUST
ENOUGH TO HELP SUSTAIN THE BAND UNTIL CONDITIONS COOL PAST SUNSET.
FOR THE OVERNIGHT HOURS...GLOBAL AND HI-RES MODELS DEPICT
REGENERATING ACTIVITY BACK ACROSS THE RIO GRANDE VALLEY NORTHWEST
INTO THE HILL COUNTRY AND TOWARDS THE I-35 CORRIDOR. RAP/NAM MASS
FIELDS SHOW SUPPORTIVE LOW-LVL CONVERGENT AND UPPER LEVEL DIVERGENT
COUPLETS THAT FURTHER SUPPORT THIS POSSIBILITY. LOOKING AT WATER
VAPOR...AN AREA OF ENHANCED ASCENT IS NOTED ACROSS CENTRAL MEXICO
EXTENDING BACK TO THE PACIFIC COAST AND THIS FEATURE MAY BE THE
STRONGER MID TO UPPER LEVEL WIND CORE IN ASSOCIATION WITH A
LOCALIZED VORT MAX THAT IS PROGGED TO MOVE OVER SOUTH-CENTRAL
TEXAS BETWEEN MIDNIGHT AND 7AM. PER THE GFS...H3 AND H5 WINDS
SHOULD INCREASE TOWARDS 100 KT AND NEAR 50-60 KTS RESPECTIVELY
COINCIDENTALLY WITH STRONGER HEIGHT FALLS. STEEPER MID LEVEL LAPSE
RATES OVERNIGHT SHOULD SUPPORT MORE SCATTERED THUNDERSTORM
DEVELOPMENT DURING THIS TIME FRAME. WITH PWATS 1.3-1.5"...SOME
RAINFALL RATES FROM SOME TRAINING THUNDERSTORMS COULD RESULT IN
HIGHER TOTALS AND SOME LOCALIZED MINOR FLOODING IMPACTS. HEAVY
RAINFALL RISK WILL DIMINISH THROUGH WEDNESDAY AFTERNOON AS
STRONGER LIFT MOVES EAST AS THE SHORTWAVE TROUGH AXIS PASSES.
&&
.LONG TERM (THURSDAY THROUGH TUESDAY)...
LOW CHANCES OF RAIN INITIALLY THURSDAY BUT MUCH HIGHER CHANCES OCCUR
FRIDAY THROUGH SATURDAY WITH AN ADDITIONAL 1-2 INCHES POSSIBLE FOR
THE REGION.
A STRONGER NORTHERN STREAM TROUGH AND DEVELOPING SURFACE HIGH WILL
FORCE A COLD FRONT THROUGH THE REGION MID-DAY FRIDAY. THE
COMBINATION OF THE FRONTAL CONVERGENCE AND SW SOUTHERN BRANCH
EMBEDDED H5 IMPULSES PROMOTING MID AND DEEP LAYER LIFT SHOULD
ENHANCE PRECIPITATION COVERAGE OVER MUCH OF THE REGION. WITH PWATS
RANGING FROM 1.3-1.7"...PERIODS OF MODERATE TO HEAVY RAIN FROM
THUNDERSTORMS WILL BE LIKELY FRIDAY AS SURFACE INSTABILITY COULD
RANGE FROM 500-1000 J/KG. ANOTHER LATITUDINALLY DEEP SOUTHERN STREAM
TROUGH WILL PROGRESS TOWARDS THE REGION SATURDAY...FURTHER
TEMPORALY EXTENDING THE ASCENT AND GENERATING MORE WIDESPREAD
SHOWERS WITH POSSIBLE ELEVATED THUNDERSTORMS. SOME LOCALIZED
FLOODING CONCERNS COULD AGAIN BE POSSIBLE DURING THIS TIME FRAME
WHICH IS HANDLED WELL BY CURRENT HWO. LINGERING SHOWERS/TSTORMS WILL
BE POSSIBLE SUNDAY AS THE BASE OF TROUGH AXIS PASSES EAST OF THE
REGION.
THE SHORTWAVE AXIS WILL SHIFT EAST OF THE REGION BY SUNDAY NIGHT
WITH A DRIER TREND INTO EARLY NEXT WEEK. MODELS ARE IN DISAGREEMENT
WITH EC ATTEMPTING TO BRING ANOTHER FRONT THROUGH ON TUESDAY WITH
GFS HAVING IT WELL NORTH GIVEN BIG DIFFERENCES ON NORTHERN STREAM
TROUGHING STRENGTH. MORE RUN TO RUN CONSISTANCY WILL BE NEEDED
BEOFRE FALLING IN LINE WITH A PARTICULAR SOLUTION AND WENT WITH A
LONG TERM BLEND. /ALLEN/
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 59 74 61 77 61 / 80 70 20 20 30
AUSTIN BERGSTROM INTL AIRPORT 59 73 61 76 61 / 80 70 20 20 20
NEW BRAUNFELS MUNI AIRPORT 61 74 62 77 61 / 80 60 20 20 20
BURNET MUNI AIRPORT 57 72 59 76 59 / 80 60 20 20 40
DEL RIO INTL AIRPORT 59 78 62 81 63 / 30 20 10 10 30
GEORGETOWN MUNI AIRPORT 60 72 61 76 60 / 80 70 20 20 40
HONDO MUNI AIRPORT 60 75 62 79 62 / 80 50 10 10 20
SAN MARCOS MUNI AIRPORT 60 74 62 76 61 / 80 60 20 20 20
LA GRANGE - FAYETTE REGIONAL 62 75 63 76 62 / 70 60 20 20 20
SAN ANTONIO INTL AIRPORT 60 74 63 77 62 / 80 60 20 10 20
STINSON MUNI AIRPORT 61 75 63 78 62 / 80 50 20 10 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...10
SYNOPTIC/GRIDS...15
PUBLIC SERVICE/DATA COLLECTION...00
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1240 PM CDT TUE MAR 17 2015
.AVIATION.../18Z TAFS/
IFR/MVFR CIGS CONTINUE THIS AFTERNOON ACROSS THE REGION. HIGHER
CIGS WERE LOCATED ACROSS THE WEST IN THE WAKE OF RAIN THAT MOVED
THROUGH THIS MORNING. MAIN CONCERNS FOR THIS FORECAST PERIOD WILL
BE THE CIGS...LIGHT RAIN...DRIZZLE AND ELEVATED CONVECTION.
ELEVATED CONVECTION POSSIBLE AFTER 05Z AS INSTABILITY INCREASES
ACROSS THE REGION. FIRST ROUND OF LIGHT RAIN AND RAIN SHOWERS
SHOULD PROGRESS TOWARDS SAN ANTONIO BETWEEN 19Z-21Z AND 22Z-00Z
FOR AUSTIN. SECOND ROUND WILL LIKELY IMPACT KDRT BETWEEN 02Z-06Z
THEN SPREAD EAST AND IMPACT THE I-35 TERMINALS STARTING AROUND
05Z. LIKELY TO SEE HIGHER RAINFALL RATES AND SOME ELEVATED
CONVECTION. EXPECTING CIGS TO REMAIN IFR/MVFR THROUGH THE FORECAST
PERIOD. WINDS WILL BE S/SE AT 5-10 KNOTS THROUGHOUT THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 954 AM CDT TUE MAR 17 2015/
UPDATE...GOING FORECAST FOR TODAY IN GOOD SHAPE WITH SLIGHT POP
INCREASES AND DECREASES REGIONALLY TO BETTER TIME THE RAIN BAND
POISED TO MOVE THROUGH THE REGION LATE THIS MORNING AND THROUGH
THE AFTERNOON TO EVENING. HAVE EXPIRED THE DENSE FOG ADVISORY WITH
IMPROVING VISIBILITIES OVER THE PAST HOUR. UPDATES ARE OUT AND
UPDATED DISCUSSION CAN BE FOUND BELOW.
DISCUSSION...THE DENSE FOG IN SE ZONES AND ISOLATED AREAS ALONG
THE I-35 CORRIDOR HAVE IMPROVED OVER THE LAST HOUR WITH MOST
READINGS NOW ABOVE 1SM. THIS TREND WILL SLOWLY CONTINUE THROUGH
THE MID TO LATE MORNING. A LIGHT RAIN BAND IN NOTED ON REGIONAL
RADARS ACROSS THE RIO GRANDE VALLEY THAT IS SLOWLY PIVOTING NORTH
AND EAST. DEEP SOUTHERLY COLUMN FLOW WILL KEEP EASTWARD
PROGRESSION OF THE BAND SLOW THROUGH THE DAY. BASED ON LATEST HI-
RES TRENDS...HAVE SLIGHTLY CUT BACK ON POPS (-10%) IN EASTERN
AREAS NOW THROUGH THE EARLY AFTERNOON WITH SLIGHT INCREASES
(+10%) FOR WEST-CENTRAL LOCATIONS. LATEST HRRR...TEXAS TECH
WRF...AND 12Z NAM HAVE BAND ENTERING THE I-35 CORRIDOR 2-4PM OVER
BEXAR AND TOWARDS AUSTIN BY 5-7PM. SOME EMBEDDED ELEVATED
THUNDERSTORMS COULD OCCUR WITH THIS BAND BUT MUCAPE LOOKS TO
INCREASE MORE OVERNIGHT AND INTO WEDNESDAY MORNING FOR THE SECOND
POTENTIAL ROUND. THE PREVIOUS DISCUSSION HANDLES THIS SITUATION
WELL AND MORE DETAILS CAN BE FOUND THERE. /ALLEN/
PREV DISCUSSION... /ISSUED 630 AM CDT TUE MAR 17 2015/
AVIATION DISCUSSION...FOR 12Z TAF PACKAGE...
LATEST RADAR AND SATELLITE TRENDS SHOW RAIN DEVELOPING ON THE
MEXICAN SIDE OF THE RIO GRANDE AND MOVING NORTH. THESE SHOWERS
WILL BEING TO ARRIVE IN THE VICINITY OF KDRT WITHIN THE FIRST FEW
HOURS OF THE TAF PERIOD. HOWEVER...RAIN SHOULD EXIT THE TERMINAL
BY MID AFTERNOON KEEPING THE TERMINAL IN MVFR CIG CATEGORY THROUGH
THE REMAINDER OF THE AFTERNOON AND BACK TO VFR AFTER DARK.
FOR THE I35 TERMINALS...LIFR/IFR CIGS AND BR WILL PERSIST UNTIL
RAIN ARRIVE AROUND MID DAY. CIGS WILL ACTUALLY IMPROVE TO MVFR
EVEN WITH THE RAIN AT FIRST. HEAVIER RAIN POTENTIAL DURING THE
LATE AFTERNOON AND EVENING MAY PERIODICALLY REDUCE VIS AND CIGS SO
INCLUDED PROB30 AT KSAT/KSSF TO ACCOUNT FOR THIS. RAIN POTENTIAL
SHOULD THEN PERSIST THROUGH THE OVERNIGHT PERIOD FOR ALL I35
TERMINALS.
PREV DISCUSSION... /ISSUED 616 AM CDT TUE MAR 17 2015/
UPDATE...
VISIBILITIES ACROSS THE SOUTHEASTERN COUNTIES HAVE DROPPED TO 1/4
OF A MILE AND HAVE ISSUED A DENSE FOG ADVISORY UNTIL 15Z /10 AM/.
PRODUCTS HAVE BEEN SENT.
HAMPSHIRE
PREV DISCUSSION... /ISSUED 354 AM CDT TUE MAR 17 2015/
SHORT TERM (TODAY THROUGH WEDNESDAY)...
THE ATMOSPHERE CONTINUES TO MOISTEN OVERNIGHT WITH TWO MAIN AREAS
OF SATURATION ONGOING IN THE COLUMN. FIRST IS ABUNDANT UPPER
LEVEL MOISTURE THAT CAN EASILY BE SEEN ON IR SATELLITE IMAGERY.
THE LOWER LEVELS OF THE ATMOSPHERE ARE NEARLY SATURATED AS WELL
WITH LOW CLOUDS AND SOME FOG BEING REPORTED ACROSS THE
AREA...MAINLY NEAR THE BALCONES ESCARPMENT. THE LOW-LEVEL
SATURATION IN COMBINATION WITH 25 KNOTS OF SOUTHERLY FLOW IS
LEADING TO SOME POCKETS OF LIGHT DRIZZLE. THIS SHOULD CONTINUE
THROUGH THE MORNING HOURS. WITH THE LOWER AND UPPER LEVELS OF THE
ATMOSPHERE NEARLY SATURATED...ALL THAT REMAINS IS THE MID LEVELS
WHICH REMAIN FAIRLY DRY. CURRENT RAP ANALYSIS SHOWS 700 MB RH
VALUES IN THE 20 TO 50 PERCENT RANGE ACROSS MUCH OF THE AREA.
CHANCES FOR SUBSTANTIAL RAINFALL WILL BE MINIMAL AS LONG AS THE
MID-LEVELS CONTINUE TO BE FAIRLY DRY. HOWEVER...AS THE UPPER LOW
APPROACHES THE AREA MOISTENING OF THE MID-LEVELS SHOULD OCCUR. THE
RAP IS SHOWING MOISTURE INCREASING WITHIN THE NEXT SEVERAL HOURS
WITH SATURATION AT 700 MB FOR THE WESTERN HALF OF THE AREA BY 16Z.
NOW WE KNOW WHEN THE BEST MOISTURE FOR PRECIPITATION PRODUCTION
WILL OCCUR...THE NEXT QUESTION IS WHEN WILL THE DEEP LIFT ARRIVE
TO THE AREA AND HOW LONG THE LIFTING WILL REMAIN IN PLACE.
CURRENTLY...THE CENTER OF THE UPPER LOW IS LOCATED EAST OF BAJA
ACROSS WESTERN MEXICO. LAST NIGHT THERE WERE SOME MODELS WHICH
MOVED THE CENTER OF THE LOW NEAR DEL RIO WHILE SOME MOVED THE
CENTER OF THE LOW CLOSER TO WEST TEXAS. A 00Z 500 MB ANALYSIS
GIVES US A GOOD IDEA ON THE EXPECTED TRACK. THE RIDGE AXIS HAS
SHIFTED EAST AND IS NOW CENTERED IN THE NORTHERN GULF OF
MEXICO...AND EXTENDS NNW INTO NORTH TEXAS AND OKLAHOMA. THE
BROWNSVILLE AND CORPUS CHRISTI RAOBS HAD SLIGHT HEIGHT RISES
WHICH INDICATES THE RIDGE IS SLIGHTLY STRENGTHENING OR BUILDING
WEST. UPPER AIR SITES IN WEST TEXAS AND THE PANHANDLE INDICATE
LITTLE CHANGE IN THE 500 HEIGHT AND THIS IS WHERE THE UPPER LOW
SHOULD WANT TO GO. MOST IF NOT ALL THE LATEST MODEL GUIDANCE HAS
PICKED UP ON THIS AND HAS THE LOW TRACKING ACROSS WESTERN TEXAS
LATE THIS EVENING AND OVERNIGHT.
THIS IS A SOMEWHAT UNUSUAL UPPER LOW FOR SOUTH-CENTRAL
TEXAS...GIVEN THE CURRENT POSITION IS SO FAR TO THE SOUTH. WITH
THE LOW MOVING TO THE NNE THE BEST POTENTIAL VORTICITY ADVECTION
WILL BE JUST TO OUR NORTHWEST. HOWEVER...A BAND OF LOW- LEVEL
CONFLUENCE SHOULD SET UP NEAR THE HIGHWAY 83 CORRIDOR BY THE LATE
MORNING HOURS. THIS FEATURE IN COMBINATION WITH THE SOME UPPER
SUPPORT WILL LEAD TO AN AREA OF HIGHER RAINFALL. AT THE PRESENT
TIME...IT LOOKS LIKE THIS BAND OF HEAVIER RAIN WILL INITIALLY FALL
BETWEEN THE HIGHWAY 83 AND I-35/37 CORRIDOR BEGINNING AROUND MIDDAY
ONCE THE MID-LEVELS OF THE ATMOSPHERE SATURATE. WITH THE UPPER LOW
MOVING MORE NORTH THAN EAST...THIS ZONE OF N-S LIFT WILL BE SLOW
TO SHIFT EAST BUT WILL SLOWLY DO SO THIS AFTERNOON THROUGH THE
EVENING...EVENTUALLY MAKING IT EAST OF THE I-35/37 CORRIDOR. WILL
SHOW THIS EXPECTED PROGRESSION IN THE POP FORECAST.
AFTER THIS INITIAL AREA OF RAINFALL DEVELOPS AND MOVES EAST...THE
FOCUS THEN SHIFTS ON ANY ADDITIONAL ACTIVITY OVERNIGHT TUESDAY.
THE ECMWF IS FORECASTING AN ENHANCED VORT MAX ROTATING ON THE
SOUTHERN PERIPHERY OF THE UPPER LOW...MOVING INTO THE CWA. THE
GFS/NAM ARE MUCH WEAKER WITH THIS FEATURE. UNFORTUNATELY OUR ONLY
CLUE TO THIS FEATURE WOULD BE LOOKING AT WATER VAPOR IMAGERY.
THERE DOES SEEM TO BE AN ENHANCEMENT CURRENTLY ON THE BACKSIDE OF
THE LOW...BUT IT IS DIFFICULT TO ASCERTAIN IF THIS IS WHAT THE
ECMWF IS PICKING UP ON. THINK THE MOST LIKELY SCENARIO IS WHAT THE
GFS/NAM ARE SHOWING AND THAT IS INCREASED ISENTROPIC ASCENT
DEVELOPING OVERNIGHT...LEADING TO MAINLY SCATTERED TO NUMEROUS
ACTIVITY. THERE SHOULD BE ENOUGH ACTIVITY IN THE OVERNIGHT HOURS
TO WARRANT ANOTHER PERIOD OF LIKELY POPS. WEAK LIFT WILL OCCUR FOR
THE EASTERN HALF ON WEDNESDAY AND WILL CONTINUE WITH DECENT POPS
IN THE FORECAST.
FORECAST SOUNDINGS CONTINUE TO SHOW WEAK INSTABILITY AND WILL
MENTION ISOLATED THUNDER. REGARDING RAINFALL TOTALS...THE
PREVIOUSLY MENTIONED AREA WHERE THE ENHANCED RAINFALL WILL OCCUR
SHOULD SEE AN AVERAGE OF 1 TO 1.5 INCHES THROUGH WEDNESDAY. THE
LACK OF SURFACE FOCUS WITH A BOUNDARY SHOULD LIMIT RAINFALL
TOTALS OVERALL AS ACTIVITY WILL BE SLIGHTLY ELEVATED. HOWEVER...
IF THE ECMWF VERIFIES WITH ITS REGENERATION TUESDAY NIGHT...THE
TOTALS COULD GO UP ANOTHER HALF AN INCH OR SO. THIS AREA DID NOT
SEE AS MUCH WITH THE LAST EVENT AND CAN EASILY TAKE THESE TOTALS.
HOWEVER...WILL MENTION LOCALLY HEAVY RAINFALL IN THE HWO AND
GRAPHICS TO ACCOUNT FOR ANY SLIGHTLY HIGHER RAINFALL TOTALS OR
POSSIBLE EASTWARD SHIFT WITH THE HEAVIEST BAND OF RAIN TO AREA
WHERE HEAVIER RAIN DID FALL LAST WEEK.
LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...
SLIGHT CHANCE POPS WILL CONTINUE ACROSS THE NORTHERN AND EASTERN
AREAS WEDNESDAY NIGHT AND THURSDAY...BUT NOT EXPECTING ANY
WIDESPREAD ACTIVITY IN THIS TIME FRAME. THIS PERIOD WILL SERVE AS
A TRANSITION BETWEEN UPPER LOWS. THE NEXT UPPER LOW WILL APPROACH
THE AREA ON FRIDAY. AT THE SAME TIME A TROUGH WILL PASS THROUGH
THE CENTRAL PLAINS SENDING A COLD FRONT THROUGH THE CWA ON FRIDAY.
THE UPPER SUPPORT WITH THIS SYSTEM WILL BE COMBINED WITH A SURFACE
BOUNDARY INITIALLY...BUT THIS FOCUS WILL QUICKLY BE LOST AS THE
FRONT MOVES INTO SOUTH TEXAS. RAIN WILL CONTINUE POST FRONTAL
THROUGH SATURDAY AS THE UPPER LOW REMAINS TO THE WEST OF THE AREA
AND WARMER AIR IS LIFTED ON TOP OF THE FRONTAL INVERSION. THERE
STILL APPEARS TO BE A CHANCE THE 850 FRONT MAKES IT TO THE AREA
AND THIS COULD SERVE AS AN ENHANCEMENT IN THE LIFT LEADING TO A
BAND OF HEAVIER TOTALS FALLING SOMEWHERE IN THE REGION. IT IS
STILL TOO EARLY TO GET INTO THE SPECIFICS REGARDING WHERE THIS
WILL OCCUR. PW VALUES WILL BE SLIGHTLY HIGHER WITH THIS EVENT AS
WELL. FLOODING POTENTIAL IS THERE WITH THIS SECOND EVENT BUT SOME
OF IT WILL DEPEND ON HOW MUCH RAIN FALLS FROM THE FIRST EVENT AND
WHERE. THE FLOOD POTENTIAL WOULD PRIMARILY BE TO RIVERS FROM
EXCESSIVE RUNOFF FROM THE TWO LONG DURATION EVENTS. CAPE VALUES
WILL SUPPORT SOME THUNDERSTORMS WITH THIS EVENT AS WELL...BUT WILL
REMAIN ISOLATED.
RAIN SHOULD MOVE EAST OF THE AREA BY SUNDAY AND THE REST OF THE
FORECAST PERIOD SHOULD REMAIN MOSTLY DRY. THE GFS/ECMWF IS
SHOWING ANOTHER FRONT WITH POSSIBLE LIGHT RAIN MONDAY AFTERNOON
AND MONDAY NIGHT BUT WILL NOT MENTION ANYTHING AT THIS TIME DUE TO
SOME TIMING DISCREPANCIES.
HAMPSHIRE
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 74 59 73 60 76 / 60 70 60 20 20
AUSTIN BERGSTROM INTL AIRPORT 73 59 73 60 75 / 50 70 60 20 20
NEW BRAUNFELS MUNI AIRPORT 73 60 75 60 76 / 80 80 60 20 10
BURNET MUNI AIRPORT 70 57 72 58 75 / 60 70 50 20 20
DEL RIO INTL AIRPORT 70 58 77 60 81 / 50 30 20 10 10
GEORGETOWN MUNI AIRPORT 71 59 72 59 75 / 50 70 60 20 20
HONDO MUNI AIRPORT 70 59 75 60 78 / 80 70 50 10 10
SAN MARCOS MUNI AIRPORT 71 60 74 60 76 / 60 80 60 20 10
LA GRANGE - FAYETTE REGIONAL 75 62 73 62 75 / 40 60 60 20 20
SAN ANTONIO INTL AIRPORT 73 60 74 61 76 / 90 80 50 20 10
STINSON MUNI AIRPORT 69 60 75 62 77 / 90 80 50 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...15
SYNOPTIC/GRIDS...10
PUBLIC SERVICE/DATA COLLECTION...00
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
954 AM CDT TUE MAR 17 2015
.UPDATE...GOING FORECAST FOR TODAY IN GOOD SHAPE WITH SLIGHT POP
INCREASES AND DECREASES REGIONALLY TO BETTER TIME THE RAIN BAND
POISED TO MOVE THROUGH THE REGION LATE THIS MORNING AND THROUGH
THE AFTERNOON TO EVENING. HAVE EXPIRED THE DENSE FOG ADVISORY WITH
IMPROVING VISIBILITIES OVER THE PAST HOUR. UPDATES ARE OUT AND
UPDATED DISCUSSION CAN BE FOUND BELOW.
&&
.DISCUSSION...THE DENSE FOG IN SE ZONES AND ISOLATED AREAS ALONG
THE I-35 CORRIDOR HAVE IMPROVED OVER THE LAST HOUR WITH MOST
READINGS NOW ABOVE 1SM. THIS TREND WILL SLOWLY CONTINUE THROUGH
THE MID TO LATE MORNING. A LIGHT RAIN BAND IN NOTED ON REGIONAL
RADARS ACROSS THE RIO GRANDE VALLEY THAT IS SLOWLY PIVOTING NORTH
AND EAST. DEEP SOUTHERLY COLUMN FLOW WILL KEEP EASTWARD
PROGRESSION OF THE BAND SLOW THROUGH THE DAY. BASED ON LATEST HI-
RES TRENDS...HAVE SLIGHTLY CUT BACK ON POPS (-10%) IN EASTERN
AREAS NOW THROUGH THE EARLY AFTERNOON WITH SLIGHT INCREASES
(+10%) FOR WEST-CENTRAL LOCATIONS. LATEST HRRR...TEXAS TECH
WRF...AND 12Z NAM HAVE BAND ENTERING THE I-35 CORRIDOR 2-4PM OVER
BEXAR AND TOWARDS AUSTIN BY 5-7PM. SOME EMBEDDED ELEVATED
THUNDERSTORMS COULD OCCUR WITH THIS BAND BUT MUCAPE LOOKS TO
INCREASE MORE OVERNIGHT AND INTO WEDNESDAY MORNING FOR THE SECOND
POTENTIAL ROUND. THE PREVIOUS DISCUSSION HANDLES THIS SITUATION
WELL AND MORE DETAILS CAN BE FOUND THERE. /ALLEN/
&&
.PREV DISCUSSION... /ISSUED 630 AM CDT TUE MAR 17 2015/
AVIATION DISCUSSION...FOR 12Z TAF PACKAGE...
LATEST RADAR AND SATELLITE TRENDS SHOW RAIN DEVELOPING ON THE
MEXICAN SIDE OF THE RIO GRANDE AND MOVING NORTH. THESE SHOWERS
WILL BEING TO ARRIVE IN THE VICINITY OF KDRT WITHIN THE FIRST FEW
HOURS OF THE TAF PERIOD. HOWEVER...RAIN SHOULD EXIT THE TERMINAL
BY MID AFTERNOON KEEPING THE TERMINAL IN MVFR CIG CATEGORY THROUGH
THE REMAINDER OF THE AFTERNOON AND BACK TO VFR AFTER DARK.
FOR THE I35 TERMINALS...LIFR/IFR CIGS AND BR WILL PERSIST UNTIL
RAIN ARRIVE AROUND MID DAY. CIGS WILL ACTUALLY IMPROVE TO MVFR
EVEN WITH THE RAIN AT FIRST. HEAVIER RAIN POTENTIAL DURING THE
LATE AFTERNOON AND EVENING MAY PERIODICALLY REDUCE VIS AND CIGS SO
INCLUDED PROB30 AT KSAT/KSSF TO ACCOUNT FOR THIS. RAIN POTENTIAL
SHOULD THEN PERSIST THROUGH THE OVERNIGHT PERIOD FOR ALL I35
TERMINALS.
PREV DISCUSSION... /ISSUED 616 AM CDT TUE MAR 17 2015/
UPDATE...
VISIBILITIES ACROSS THE SOUTHEASTERN COUNTIES HAVE DROPPED TO 1/4
OF A MILE AND HAVE ISSUED A DENSE FOG ADVISORY UNTIL 15Z /10 AM/.
PRODUCTS HAVE BEEN SENT.
HAMPSHIRE
PREV DISCUSSION... /ISSUED 354 AM CDT TUE MAR 17 2015/
SHORT TERM (TODAY THROUGH WEDNESDAY)...
THE ATMOSPHERE CONTINUES TO MOISTEN OVERNIGHT WITH TWO MAIN AREAS
OF SATURATION ONGOING IN THE COLUMN. FIRST IS ABUNDANT UPPER
LEVEL MOISTURE THAT CAN EASILY BE SEEN ON IR SATELLITE IMAGERY.
THE LOWER LEVELS OF THE ATMOSPHERE ARE NEARLY SATURATED AS WELL
WITH LOW CLOUDS AND SOME FOG BEING REPORTED ACROSS THE
AREA...MAINLY NEAR THE BALCONES ESCARPMENT. THE LOW-LEVEL
SATURATION IN COMBINATION WITH 25 KNOTS OF SOUTHERLY FLOW IS
LEADING TO SOME POCKETS OF LIGHT DRIZZLE. THIS SHOULD CONTINUE
THROUGH THE MORNING HOURS. WITH THE LOWER AND UPPER LEVELS OF THE
ATMOSPHERE NEARLY SATURATED...ALL THAT REMAINS IS THE MID LEVELS
WHICH REMAIN FAIRLY DRY. CURRENT RAP ANALYSIS SHOWS 700 MB RH
VALUES IN THE 20 TO 50 PERCENT RANGE ACROSS MUCH OF THE AREA.
CHANCES FOR SUBSTANTIAL RAINFALL WILL BE MINIMAL AS LONG AS THE
MID-LEVELS CONTINUE TO BE FAIRLY DRY. HOWEVER...AS THE UPPER LOW
APPROACHES THE AREA MOISTENING OF THE MID-LEVELS SHOULD OCCUR. THE
RAP IS SHOWING MOISTURE INCREASING WITHIN THE NEXT SEVERAL HOURS
WITH SATURATION AT 700 MB FOR THE WESTERN HALF OF THE AREA BY 16Z.
NOW WE KNOW WHEN THE BEST MOISTURE FOR PRECIPITATION PRODUCTION
WILL OCCUR...THE NEXT QUESTION IS WHEN WILL THE DEEP LIFT ARRIVE
TO THE AREA AND HOW LONG THE LIFTING WILL REMAIN IN PLACE.
CURRENTLY...THE CENTER OF THE UPPER LOW IS LOCATED EAST OF BAJA
ACROSS WESTERN MEXICO. LAST NIGHT THERE WERE SOME MODELS WHICH
MOVED THE CENTER OF THE LOW NEAR DEL RIO WHILE SOME MOVED THE
CENTER OF THE LOW CLOSER TO WEST TEXAS. A 00Z 500 MB ANALYSIS
GIVES US A GOOD IDEA ON THE EXPECTED TRACK. THE RIDGE AXIS HAS
SHIFTED EAST AND IS NOW CENTERED IN THE NORTHERN GULF OF
MEXICO...AND EXTENDS NNW INTO NORTH TEXAS AND OKLAHOMA. THE
BROWNSVILLE AND CORPUS CHRISTI RAOBS HAD SLIGHT HEIGHT RISES
WHICH INDICATES THE RIDGE IS SLIGHTLY STRENGTHENING OR BUILDING
WEST. UPPER AIR SITES IN WEST TEXAS AND THE PANHANDLE INDICATE
LITTLE CHANGE IN THE 500 HEIGHT AND THIS IS WHERE THE UPPER LOW
SHOULD WANT TO GO. MOST IF NOT ALL THE LATEST MODEL GUIDANCE HAS
PICKED UP ON THIS AND HAS THE LOW TRACKING ACROSS WESTERN TEXAS
LATE THIS EVENING AND OVERNIGHT.
THIS IS A SOMEWHAT UNUSUAL UPPER LOW FOR SOUTH-CENTRAL
TEXAS...GIVEN THE CURRENT POSITION IS SO FAR TO THE SOUTH. WITH
THE LOW MOVING TO THE NNE THE BEST POTENTIAL VORTICITY ADVECTION
WILL BE JUST TO OUR NORTHWEST. HOWEVER...A BAND OF LOW- LEVEL
CONFLUENCE SHOULD SET UP NEAR THE HIGHWAY 83 CORRIDOR BY THE LATE
MORNING HOURS. THIS FEATURE IN COMBINATION WITH THE SOME UPPER
SUPPORT WILL LEAD TO AN AREA OF HIGHER RAINFALL. AT THE PRESENT
TIME...IT LOOKS LIKE THIS BAND OF HEAVIER RAIN WILL INITIALLY FALL
BETWEEN THE HIGHWAY 83 AND I-35/37 CORRIDOR BEGINNING AROUND MIDDAY
ONCE THE MID-LEVELS OF THE ATMOSPHERE SATURATE. WITH THE UPPER LOW
MOVING MORE NORTH THAN EAST...THIS ZONE OF N-S LIFT WILL BE SLOW
TO SHIFT EAST BUT WILL SLOWLY DO SO THIS AFTERNOON THROUGH THE
EVENING...EVENTUALLY MAKING IT EAST OF THE I-35/37 CORRIDOR. WILL
SHOW THIS EXPECTED PROGRESSION IN THE POP FORECAST.
AFTER THIS INITIAL AREA OF RAINFALL DEVELOPS AND MOVES EAST...THE
FOCUS THEN SHIFTS ON ANY ADDITIONAL ACTIVITY OVERNIGHT TUESDAY.
THE ECMWF IS FORECASTING AN ENHANCED VORT MAX ROTATING ON THE
SOUTHERN PERIPHERY OF THE UPPER LOW...MOVING INTO THE CWA. THE
GFS/NAM ARE MUCH WEAKER WITH THIS FEATURE. UNFORTUNATELY OUR ONLY
CLUE TO THIS FEATURE WOULD BE LOOKING AT WATER VAPOR IMAGERY.
THERE DOES SEEM TO BE AN ENHANCEMENT CURRENTLY ON THE BACKSIDE OF
THE LOW...BUT IT IS DIFFICULT TO ASCERTAIN IF THIS IS WHAT THE
ECMWF IS PICKING UP ON. THINK THE MOST LIKELY SCENARIO IS WHAT THE
GFS/NAM ARE SHOWING AND THAT IS INCREASED ISENTROPIC ASCENT
DEVELOPING OVERNIGHT...LEADING TO MAINLY SCATTERED TO NUMEROUS
ACTIVITY. THERE SHOULD BE ENOUGH ACTIVITY IN THE OVERNIGHT HOURS
TO WARRANT ANOTHER PERIOD OF LIKELY POPS. WEAK LIFT WILL OCCUR FOR
THE EASTERN HALF ON WEDNESDAY AND WILL CONTINUE WITH DECENT POPS
IN THE FORECAST.
FORECAST SOUNDINGS CONTINUE TO SHOW WEAK INSTABILITY AND WILL
MENTION ISOLATED THUNDER. REGARDING RAINFALL TOTALS...THE
PREVIOUSLY MENTIONED AREA WHERE THE ENHANCED RAINFALL WILL OCCUR
SHOULD SEE AN AVERAGE OF 1 TO 1.5 INCHES THROUGH WEDNESDAY. THE
LACK OF SURFACE FOCUS WITH A BOUNDARY SHOULD LIMIT RAINFALL
TOTALS OVERALL AS ACTIVITY WILL BE SLIGHTLY ELEVATED. HOWEVER...
IF THE ECMWF VERIFIES WITH ITS REGENERATION TUESDAY NIGHT...THE
TOTALS COULD GO UP ANOTHER HALF AN INCH OR SO. THIS AREA DID NOT
SEE AS MUCH WITH THE LAST EVENT AND CAN EASILY TAKE THESE TOTALS.
HOWEVER...WILL MENTION LOCALLY HEAVY RAINFALL IN THE HWO AND
GRAPHICS TO ACCOUNT FOR ANY SLIGHTLY HIGHER RAINFALL TOTALS OR
POSSIBLE EASTWARD SHIFT WITH THE HEAVIEST BAND OF RAIN TO AREA
WHERE HEAVIER RAIN DID FALL LAST WEEK.
LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...
SLIGHT CHANCE POPS WILL CONTINUE ACROSS THE NORTHERN AND EASTERN
AREAS WEDNESDAY NIGHT AND THURSDAY...BUT NOT EXPECTING ANY
WIDESPREAD ACTIVITY IN THIS TIME FRAME. THIS PERIOD WILL SERVE AS
A TRANSITION BETWEEN UPPER LOWS. THE NEXT UPPER LOW WILL APPROACH
THE AREA ON FRIDAY. AT THE SAME TIME A TROUGH WILL PASS THROUGH
THE CENTRAL PLAINS SENDING A COLD FRONT THROUGH THE CWA ON FRIDAY.
THE UPPER SUPPORT WITH THIS SYSTEM WILL BE COMBINED WITH A SURFACE
BOUNDARY INITIALLY...BUT THIS FOCUS WILL QUICKLY BE LOST AS THE
FRONT MOVES INTO SOUTH TEXAS. RAIN WILL CONTINUE POST FRONTAL
THROUGH SATURDAY AS THE UPPER LOW REMAINS TO THE WEST OF THE AREA
AND WARMER AIR IS LIFTED ON TOP OF THE FRONTAL INVERSION. THERE
STILL APPEARS TO BE A CHANCE THE 850 FRONT MAKES IT TO THE AREA
AND THIS COULD SERVE AS AN ENHANCEMENT IN THE LIFT LEADING TO A
BAND OF HEAVIER TOTALS FALLING SOMEWHERE IN THE REGION. IT IS
STILL TOO EARLY TO GET INTO THE SPECIFICS REGARDING WHERE THIS
WILL OCCUR. PW VALUES WILL BE SLIGHTLY HIGHER WITH THIS EVENT AS
WELL. FLOODING POTENTIAL IS THERE WITH THIS SECOND EVENT BUT SOME
OF IT WILL DEPEND ON HOW MUCH RAIN FALLS FROM THE FIRST EVENT AND
WHERE. THE FLOOD POTENTIAL WOULD PRIMARILY BE TO RIVERS FROM
EXCESSIVE RUNOFF FROM THE TWO LONG DURATION EVENTS. CAPE VALUES
WILL SUPPORT SOME THUNDERSTORMS WITH THIS EVENT AS WELL...BUT WILL
REMAIN ISOLATED.
RAIN SHOULD MOVE EAST OF THE AREA BY SUNDAY AND THE REST OF THE
FORECAST PERIOD SHOULD REMAIN MOSTLY DRY. THE GFS/ECMWF IS
SHOWING ANOTHER FRONT WITH POSSIBLE LIGHT RAIN MONDAY AFTERNOON
AND MONDAY NIGHT BUT WILL NOT MENTION ANYTHING AT THIS TIME DUE TO
SOME TIMING DISCREPANCIES.
HAMPSHIRE
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 73 59 73 60 76 / 60 70 60 20 20
AUSTIN BERGSTROM INTL AIRPORT 73 59 73 60 75 / 50 70 60 20 20
NEW BRAUNFELS MUNI AIRPORT 73 60 75 60 76 / 80 80 60 20 10
BURNET MUNI AIRPORT 70 57 72 58 75 / 60 70 50 20 20
DEL RIO INTL AIRPORT 70 58 77 60 81 / 50 30 20 10 10
GEORGETOWN MUNI AIRPORT 73 59 72 59 75 / 50 70 60 20 20
HONDO MUNI AIRPORT 69 59 75 60 78 / 80 70 50 10 10
SAN MARCOS MUNI AIRPORT 73 60 74 60 76 / 60 80 60 20 10
LA GRANGE - FAYETTE REGIONAL 76 62 73 62 75 / 40 60 60 20 20
SAN ANTONIO INTL AIRPORT 72 60 74 61 76 / 90 80 50 20 10
STINSON MUNI AIRPORT 72 60 75 62 77 / 90 80 50 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...10
SYNOPTIC/GRIDS...15
PUBLIC SERVICE/DATA COLLECTION...00
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
630 AM CDT TUE MAR 17 2015
.AVIATION DISCUSSION...FOR 12Z TAF PACKAGE...
LATEST RADAR AND SATELLITE TRENDS SHOW RAIN DEVELOPING ON THE
MEXICAN SIDE OF THE RIO GRANDE AND MOVING NORTH. THESE SHOWERS
WILL BEING TO ARRIVE IN THE VICINITY OF KDRT WITHIN THE FIRST FEW
HOURS OF THE TAF PERIOD. HOWEVER...RAIN SHOULD EXIT THE TERMINAL
BY MID AFTERNOON KEEPING THE TERMINAL IN MVFR CIG CATEGORY THROUGH
THE REMAINDER OF THE AFTERNOON AND BACK TO VFR AFTER DARK.
FOR THE I35 TERMINALS...LIFR/IFR CIGS AND BR WILL PERSIST UNTIL
RAIN ARRIVE AROUND MID DAY. CIGS WILL ACTUALLY IMPROVE TO MVFR
EVEN WITH THE RAIN AT FIRST. HEAVIER RAIN POTENTIAL DURING THE
LATE AFTERNOON AND EVENING MAY PERIODICALLY REDUCE VIS AND CIGS SO
INCLUDED PROB30 AT KSAT/KSSF TO ACCOUNT FOR THIS. RAIN POTENTIAL
SHOULD THEN PERSIST THROUGH THE OVERNIGHT PERIOD FOR ALL I35
TERMINALS.
&&
.PREV DISCUSSION... /ISSUED 616 AM CDT TUE MAR 17 2015/
UPDATE...
VISIBILITIES ACROSS THE SOUTHEASTERN COUNTIES HAVE DROPPED TO 1/4
OF A MILE AND HAVE ISSUED A DENSE FOG ADVISORY UNTIL 15Z /10 AM/.
PRODUCTS HAVE BEEN SENT.
HAMPSHIRE
PREV DISCUSSION... /ISSUED 354 AM CDT TUE MAR 17 2015/
SHORT TERM (TODAY THROUGH WEDNESDAY)...
THE ATMOSPHERE CONTINUES TO MOISTEN OVERNIGHT WITH TWO MAIN AREAS
OF SATURATION ONGOING IN THE COLUMN. FIRST IS ABUNDANT UPPER
LEVEL MOISTURE THAT CAN EASILY BE SEEN ON IR SATELLITE IMAGERY.
THE LOWER LEVELS OF THE ATMOSPHERE ARE NEARLY SATURATED AS WELL
WITH LOW CLOUDS AND SOME FOG BEING REPORTED ACROSS THE
AREA...MAINLY NEAR THE BALCONES ESCARPMENT. THE LOW-LEVEL
SATURATION IN COMBINATION WITH 25 KNOTS OF SOUTHERLY FLOW IS
LEADING TO SOME POCKETS OF LIGHT DRIZZLE. THIS SHOULD CONTINUE
THROUGH THE MORNING HOURS. WITH THE LOWER AND UPPER LEVELS OF THE
ATMOSPHERE NEARLY SATURATED...ALL THAT REMAINS IS THE MID LEVELS
WHICH REMAIN FAIRLY DRY. CURRENT RAP ANALYSIS SHOWS 700 MB RH
VALUES IN THE 20 TO 50 PERCENT RANGE ACROSS MUCH OF THE AREA.
CHANCES FOR SUBSTANTIAL RAINFALL WILL BE MINIMAL AS LONG AS THE
MID-LEVELS CONTINUE TO BE FAIRLY DRY. HOWEVER...AS THE UPPER LOW
APPROACHES THE AREA MOISTENING OF THE MID-LEVELS SHOULD OCCUR. THE
RAP IS SHOWING MOISTURE INCREASING WITHIN THE NEXT SEVERAL HOURS
WITH SATURATION AT 700 MB FOR THE WESTERN HALF OF THE AREA BY 16Z.
NOW WE KNOW WHEN THE BEST MOISTURE FOR PRECIPITATION PRODUCTION
WILL OCCUR...THE NEXT QUESTION IS WHEN WILL THE DEEP LIFT ARRIVE
TO THE AREA AND HOW LONG THE LIFTING WILL REMAIN IN PLACE.
CURRENTLY...THE CENTER OF THE UPPER LOW IS LOCATED EAST OF BAJA
ACROSS WESTERN MEXICO. LAST NIGHT THERE WERE SOME MODELS WHICH
MOVED THE CENTER OF THE LOW NEAR DEL RIO WHILE SOME MOVED THE
CENTER OF THE LOW CLOSER TO WEST TEXAS. A 00Z 500 MB ANALYSIS
GIVES US A GOOD IDEA ON THE EXPECTED TRACK. THE RIDGE AXIS HAS
SHIFTED EAST AND IS NOW CENTERED IN THE NORTHERN GULF OF
MEXICO...AND EXTENDS NNW INTO NORTH TEXAS AND OKLAHOMA. THE
BROWNSVILLE AND CORPUS CHRISTI RAOBS HAD SLIGHT HEIGHT RISES
WHICH INDICATES THE RIDGE IS SLIGHTLY STRENGTHENING OR BUILDING
WEST. UPPER AIR SITES IN WEST TEXAS AND THE PANHANDLE INDICATE
LITTLE CHANGE IN THE 500 HEIGHT AND THIS IS WHERE THE UPPER LOW
SHOULD WANT TO GO. MOST IF NOT ALL THE LATEST MODEL GUIDANCE HAS
PICKED UP ON THIS AND HAS THE LOW TRACKING ACROSS WESTERN TEXAS
LATE THIS EVENING AND OVERNIGHT.
THIS IS A SOMEWHAT UNUSUAL UPPER LOW FOR SOUTH-CENTRAL
TEXAS...GIVEN THE CURRENT POSITION IS SO FAR TO THE SOUTH. WITH
THE LOW MOVING TO THE NNE THE BEST POTENTIAL VORTICITY ADVECTION
WILL BE JUST TO OUR NORTHWEST. HOWEVER...A BAND OF LOW- LEVEL
CONFLUENCE SHOULD SET UP NEAR THE HIGHWAY 83 CORRIDOR BY THE LATE
MORNING HOURS. THIS FEATURE IN COMBINATION WITH THE SOME UPPER
SUPPORT WILL LEAD TO AN AREA OF HIGHER RAINFALL. AT THE PRESENT
TIME...IT LOOKS LIKE THIS BAND OF HEAVIER RAIN WILL INITIALLY FALL
BETWEEN THE HIGHWAY 83 AND I-35/37 CORRIDOR BEGINNING AROUND MIDDAY
ONCE THE MID-LEVELS OF THE ATMOSPHERE SATURATE. WITH THE UPPER LOW
MOVING MORE NORTH THAN EAST...THIS ZONE OF N-S LIFT WILL BE SLOW
TO SHIFT EAST BUT WILL SLOWLY DO SO THIS AFTERNOON THROUGH THE
EVENING...EVENTUALLY MAKING IT EAST OF THE I-35/37 CORRIDOR. WILL
SHOW THIS EXPECTED PROGRESSION IN THE POP FORECAST.
AFTER THIS INITIAL AREA OF RAINFALL DEVELOPS AND MOVES EAST...THE
FOCUS THEN SHIFTS ON ANY ADDITIONAL ACTIVITY OVERNIGHT TUESDAY.
THE ECMWF IS FORECASTING AN ENHANCED VORT MAX ROTATING ON THE
SOUTHERN PERIPHERY OF THE UPPER LOW...MOVING INTO THE CWA. THE
GFS/NAM ARE MUCH WEAKER WITH THIS FEATURE. UNFORTUNATELY OUR ONLY
CLUE TO THIS FEATURE WOULD BE LOOKING AT WATER VAPOR IMAGERY.
THERE DOES SEEM TO BE AN ENHANCEMENT CURRENTLY ON THE BACKSIDE OF
THE LOW...BUT IT IS DIFFICULT TO ASCERTAIN IF THIS IS WHAT THE
ECMWF IS PICKING UP ON. THINK THE MOST LIKELY SCENARIO IS WHAT THE
GFS/NAM ARE SHOWING AND THAT IS INCREASED ISENTROPIC ASCENT
DEVELOPING OVERNIGHT...LEADING TO MAINLY SCATTERED TO NUMEROUS
ACTIVITY. THERE SHOULD BE ENOUGH ACTIVITY IN THE OVERNIGHT HOURS
TO WARRANT ANOTHER PERIOD OF LIKELY POPS. WEAK LIFT WILL OCCUR FOR
THE EASTERN HALF ON WEDNESDAY AND WILL CONTINUE WITH DECENT POPS
IN THE FORECAST.
FORECAST SOUNDINGS CONTINUE TO SHOW WEAK INSTABILITY AND WILL
MENTION ISOLATED THUNDER. REGARDING RAINFALL TOTALS...THE
PREVIOUSLY MENTIONED AREA WHERE THE ENHANCED RAINFALL WILL OCCUR
SHOULD SEE AN AVERAGE OF 1 TO 1.5 INCHES THROUGH WEDNESDAY. THE
LACK OF SURFACE FOCUS WITH A BOUNDARY SHOULD LIMIT RAINFALL
TOTALS OVERALL AS ACTIVITY WILL BE SLIGHTLY ELEVATED. HOWEVER...
IF THE ECMWF VERIFIES WITH ITS REGENERATION TUESDAY NIGHT...THE
TOTALS COULD GO UP ANOTHER HALF AN INCH OR SO. THIS AREA DID NOT
SEE AS MUCH WITH THE LAST EVENT AND CAN EASILY TAKE THESE TOTALS.
HOWEVER...WILL MENTION LOCALLY HEAVY RAINFALL IN THE HWO AND
GRAPHICS TO ACCOUNT FOR ANY SLIGHTLY HIGHER RAINFALL TOTALS OR
POSSIBLE EASTWARD SHIFT WITH THE HEAVIEST BAND OF RAIN TO AREA
WHERE HEAVIER RAIN DID FALL LAST WEEK.
LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...
SLIGHT CHANCE POPS WILL CONTINUE ACROSS THE NORTHERN AND EASTERN
AREAS WEDNESDAY NIGHT AND THURSDAY...BUT NOT EXPECTING ANY
WIDESPREAD ACTIVITY IN THIS TIME FRAME. THIS PERIOD WILL SERVE AS
A TRANSITION BETWEEN UPPER LOWS. THE NEXT UPPER LOW WILL APPROACH
THE AREA ON FRIDAY. AT THE SAME TIME A TROUGH WILL PASS THROUGH
THE CENTRAL PLAINS SENDING A COLD FRONT THROUGH THE CWA ON FRIDAY.
THE UPPER SUPPORT WITH THIS SYSTEM WILL BE COMBINED WITH A SURFACE
BOUNDARY INITIALLY...BUT THIS FOCUS WILL QUICKLY BE LOST AS THE
FRONT MOVES INTO SOUTH TEXAS. RAIN WILL CONTINUE POST FRONTAL
THROUGH SATURDAY AS THE UPPER LOW REMAINS TO THE WEST OF THE AREA
AND WARMER AIR IS LIFTED ON TOP OF THE FRONTAL INVERSION. THERE
STILL APPEARS TO BE A CHANCE THE 850 FRONT MAKES IT TO THE AREA
AND THIS COULD SERVE AS AN ENHANCEMENT IN THE LIFT LEADING TO A
BAND OF HEAVIER TOTALS FALLING SOMEWHERE IN THE REGION. IT IS
STILL TOO EARLY TO GET INTO THE SPECIFICS REGARDING WHERE THIS
WILL OCCUR. PW VALUES WILL BE SLIGHTLY HIGHER WITH THIS EVENT AS
WELL. FLOODING POTENTIAL IS THERE WITH THIS SECOND EVENT BUT SOME
OF IT WILL DEPEND ON HOW MUCH RAIN FALLS FROM THE FIRST EVENT AND
WHERE. THE FLOOD POTENTIAL WOULD PRIMARILY BE TO RIVERS FROM
EXCESSIVE RUNOFF FROM THE TWO LONG DURATION EVENTS. CAPE VALUES
WILL SUPPORT SOME THUNDERSTORMS WITH THIS EVENT AS WELL...BUT WILL
REMAIN ISOLATED.
RAIN SHOULD MOVE EAST OF THE AREA BY SUNDAY AND THE REST OF THE
FORECAST PERIOD SHOULD REMAIN MOSTLY DRY. THE GFS/ECMWF IS
SHOWING ANOTHER FRONT WITH POSSIBLE LIGHT RAIN MONDAY AFTERNOON
AND MONDAY NIGHT BUT WILL NOT MENTION ANYTHING AT THIS TIME DUE TO
SOME TIMING DISCREPANCIES.
HAMPSHIRE
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 73 59 73 60 76 / 60 70 60 20 20
AUSTIN BERGSTROM INTL AIRPORT 73 59 73 60 75 / 50 70 60 20 20
NEW BRAUNFELS MUNI AIRPORT 73 60 75 60 76 / 80 80 60 20 10
BURNET MUNI AIRPORT 70 57 72 58 75 / 60 70 50 20 20
DEL RIO INTL AIRPORT 70 58 77 60 81 / 50 30 20 10 10
GEORGETOWN MUNI AIRPORT 73 59 72 59 75 / 50 70 60 20 20
HONDO MUNI AIRPORT 69 59 75 60 78 / 80 70 50 10 10
SAN MARCOS MUNI AIRPORT 73 60 74 60 76 / 60 80 60 20 10
LA GRANGE - FAYETTE REGIONAL 77 62 73 62 75 / 40 60 60 20 20
SAN ANTONIO INTL AIRPORT 72 60 74 61 76 / 80 80 50 20 10
STINSON MUNI AIRPORT 72 60 75 62 77 / 80 80 50 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR THE FOLLOWING
COUNTIES: DE WITT...GONZALES...KARNES...LAVACA.
&&
$$
MESOSCALE/AVIATION...03
SYNOPTIC/GRIDS...29
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
616 AM CDT TUE MAR 17 2015
.UPDATE...
VISIBILITIES ACROSS THE SOUTHEASTERN COUNTIES HAVE DROPPED TO 1/4
OF A MILE AND HAVE ISSUED A DENSE FOG ADVISORY UNTIL 15Z /10 AM/.
PRODUCTS HAVE BEEN SENT.
HAMPSHIRE
&&
.PREV DISCUSSION... /ISSUED 354 AM CDT TUE MAR 17 2015/
SHORT TERM (TODAY THROUGH WEDNESDAY)...
THE ATMOSPHERE CONTINUES TO MOISTEN OVERNIGHT WITH TWO MAIN AREAS
OF SATURATION ONGOING IN THE COLUMN. FIRST IS ABUNDANT UPPER
LEVEL MOISTURE THAT CAN EASILY BE SEEN ON IR SATELLITE IMAGERY.
THE LOWER LEVELS OF THE ATMOSPHERE ARE NEARLY SATURATED AS WELL
WITH LOW CLOUDS AND SOME FOG BEING REPORTED ACROSS THE
AREA...MAINLY NEAR THE BALCONES ESCARPMENT. THE LOW-LEVEL
SATURATION IN COMBINATION WITH 25 KNOTS OF SOUTHERLY FLOW IS
LEADING TO SOME POCKETS OF LIGHT DRIZZLE. THIS SHOULD CONTINUE
THROUGH THE MORNING HOURS. WITH THE LOWER AND UPPER LEVELS OF THE
ATMOSPHERE NEARLY SATURATED...ALL THAT REMAINS IS THE MID LEVELS
WHICH REMAIN FAIRLY DRY. CURRENT RAP ANALYSIS SHOWS 700 MB RH
VALUES IN THE 20 TO 50 PERCENT RANGE ACROSS MUCH OF THE AREA.
CHANCES FOR SUBSTANTIAL RAINFALL WILL BE MINIMAL AS LONG AS THE
MID-LEVELS CONTINUE TO BE FAIRLY DRY. HOWEVER...AS THE UPPER LOW
APPROACHES THE AREA MOISTENING OF THE MID-LEVELS SHOULD OCCUR. THE
RAP IS SHOWING MOISTURE INCREASING WITHIN THE NEXT SEVERAL HOURS
WITH SATURATION AT 700 MB FOR THE WESTERN HALF OF THE AREA BY 16Z.
NOW WE KNOW WHEN THE BEST MOISTURE FOR PRECIPITATION PRODUCTION
WILL OCCUR...THE NEXT QUESTION IS WHEN WILL THE DEEP LIFT ARRIVE
TO THE AREA AND HOW LONG THE LIFTING WILL REMAIN IN PLACE.
CURRENTLY...THE CENTER OF THE UPPER LOW IS LOCATED EAST OF BAJA
ACROSS WESTERN MEXICO. LAST NIGHT THERE WERE SOME MODELS WHICH
MOVED THE CENTER OF THE LOW NEAR DEL RIO WHILE SOME MOVED THE
CENTER OF THE LOW CLOSER TO WEST TEXAS. A 00Z 500 MB ANALYSIS
GIVES US A GOOD IDEA ON THE EXPECTED TRACK. THE RIDGE AXIS HAS
SHIFTED EAST AND IS NOW CENTERED IN THE NORTHERN GULF OF
MEXICO...AND EXTENDS NNW INTO NORTH TEXAS AND OKLAHOMA. THE
BROWNSVILLE AND CORPUS CHRISTI RAOBS HAD SLIGHT HEIGHT RISES
WHICH INDICATES THE RIDGE IS SLIGHTLY STRENGTHENING OR BUILDING
WEST. UPPER AIR SITES IN WEST TEXAS AND THE PANHANDLE INDICATE
LITTLE CHANGE IN THE 500 HEIGHT AND THIS IS WHERE THE UPPER LOW
SHOULD WANT TO GO. MOST IF NOT ALL THE LATEST MODEL GUIDANCE HAS
PICKED UP ON THIS AND HAS THE LOW TRACKING ACROSS WESTERN TEXAS
LATE THIS EVENING AND OVERNIGHT.
THIS IS A SOMEWHAT UNUSUAL UPPER LOW FOR SOUTH-CENTRAL
TEXAS...GIVEN THE CURRENT POSITION IS SO FAR TO THE SOUTH. WITH
THE LOW MOVING TO THE NNE THE BEST POTENTIAL VORTICITY ADVECTION
WILL BE JUST TO OUR NORTHWEST. HOWEVER...A BAND OF LOW- LEVEL
CONFLUENCE SHOULD SET UP NEAR THE HIGHWAY 83 CORRIDOR BY THE LATE
MORNING HOURS. THIS FEATURE IN COMBINATION WITH THE SOME UPPER
SUPPORT WILL LEAD TO AN AREA OF HIGHER RAINFALL. AT THE PRESENT
TIME...IT LOOKS LIKE THIS BAND OF HEAVIER RAIN WILL INITIALLY FALL
BETWEEN THE HIGHWAY 83 AND I-35/37 CORRIDOR BEGINNING AROUND MIDDAY
ONCE THE MID-LEVELS OF THE ATMOSPHERE SATURATE. WITH THE UPPER LOW
MOVING MORE NORTH THAN EAST...THIS ZONE OF N-S LIFT WILL BE SLOW
TO SHIFT EAST BUT WILL SLOWLY DO SO THIS AFTERNOON THROUGH THE
EVENING...EVENTUALLY MAKING IT EAST OF THE I-35/37 CORRIDOR. WILL
SHOW THIS EXPECTED PROGRESSION IN THE POP FORECAST.
AFTER THIS INITIAL AREA OF RAINFALL DEVELOPS AND MOVES EAST...THE
FOCUS THEN SHIFTS ON ANY ADDITIONAL ACTIVITY OVERNIGHT TUESDAY.
THE ECMWF IS FORECASTING AN ENHANCED VORT MAX ROTATING ON THE
SOUTHERN PERIPHERY OF THE UPPER LOW...MOVING INTO THE CWA. THE
GFS/NAM ARE MUCH WEAKER WITH THIS FEATURE. UNFORTUNATELY OUR ONLY
CLUE TO THIS FEATURE WOULD BE LOOKING AT WATER VAPOR IMAGERY.
THERE DOES SEEM TO BE AN ENHANCEMENT CURRENTLY ON THE BACKSIDE OF
THE LOW...BUT IT IS DIFFICULT TO ASCERTAIN IF THIS IS WHAT THE
ECMWF IS PICKING UP ON. THINK THE MOST LIKELY SCENARIO IS WHAT THE
GFS/NAM ARE SHOWING AND THAT IS INCREASED ISENTROPIC ASCENT
DEVELOPING OVERNIGHT...LEADING TO MAINLY SCATTERED TO NUMEROUS
ACTIVITY. THERE SHOULD BE ENOUGH ACTIVITY IN THE OVERNIGHT HOURS
TO WARRANT ANOTHER PERIOD OF LIKELY POPS. WEAK LIFT WILL OCCUR FOR
THE EASTERN HALF ON WEDNESDAY AND WILL CONTINUE WITH DECENT POPS
IN THE FORECAST.
FORECAST SOUNDINGS CONTINUE TO SHOW WEAK INSTABILITY AND WILL
MENTION ISOLATED THUNDER. REGARDING RAINFALL TOTALS...THE
PREVIOUSLY MENTIONED AREA WHERE THE ENHANCED RAINFALL WILL OCCUR
SHOULD SEE AN AVERAGE OF 1 TO 1.5 INCHES THROUGH WEDNESDAY. THE
LACK OF SURFACE FOCUS WITH A BOUNDARY SHOULD LIMIT RAINFALL
TOTALS OVERALL AS ACTIVITY WILL BE SLIGHTLY ELEVATED. HOWEVER...
IF THE ECMWF VERIFIES WITH ITS REGENERATION TUESDAY NIGHT...THE
TOTALS COULD GO UP ANOTHER HALF AN INCH OR SO. THIS AREA DID NOT
SEE AS MUCH WITH THE LAST EVENT AND CAN EASILY TAKE THESE TOTALS.
HOWEVER...WILL MENTION LOCALLY HEAVY RAINFALL IN THE HWO AND
GRAPHICS TO ACCOUNT FOR ANY SLIGHTLY HIGHER RAINFALL TOTALS OR
POSSIBLE EASTWARD SHIFT WITH THE HEAVIEST BAND OF RAIN TO AREA
WHERE HEAVIER RAIN DID FALL LAST WEEK.
LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...
SLIGHT CHANCE POPS WILL CONTINUE ACROSS THE NORTHERN AND EASTERN
AREAS WEDNESDAY NIGHT AND THURSDAY...BUT NOT EXPECTING ANY
WIDESPREAD ACTIVITY IN THIS TIME FRAME. THIS PERIOD WILL SERVE AS
A TRANSITION BETWEEN UPPER LOWS. THE NEXT UPPER LOW WILL APPROACH
THE AREA ON FRIDAY. AT THE SAME TIME A TROUGH WILL PASS THROUGH
THE CENTRAL PLAINS SENDING A COLD FRONT THROUGH THE CWA ON FRIDAY.
THE UPPER SUPPORT WITH THIS SYSTEM WILL BE COMBINED WITH A SURFACE
BOUNDARY INITIALLY...BUT THIS FOCUS WILL QUICKLY BE LOST AS THE
FRONT MOVES INTO SOUTH TEXAS. RAIN WILL CONTINUE POST FRONTAL
THROUGH SATURDAY AS THE UPPER LOW REMAINS TO THE WEST OF THE AREA
AND WARMER AIR IS LIFTED ON TOP OF THE FRONTAL INVERSION. THERE
STILL APPEARS TO BE A CHANCE THE 850 FRONT MAKES IT TO THE AREA
AND THIS COULD SERVE AS AN ENHANCEMENT IN THE LIFT LEADING TO A
BAND OF HEAVIER TOTALS FALLING SOMEWHERE IN THE REGION. IT IS
STILL TOO EARLY TO GET INTO THE SPECIFICS REGARDING WHERE THIS
WILL OCCUR. PW VALUES WILL BE SLIGHTLY HIGHER WITH THIS EVENT AS
WELL. FLOODING POTENTIAL IS THERE WITH THIS SECOND EVENT BUT SOME
OF IT WILL DEPEND ON HOW MUCH RAIN FALLS FROM THE FIRST EVENT AND
WHERE. THE FLOOD POTENTIAL WOULD PRIMARILY BE TO RIVERS FROM
EXCESSIVE RUNOFF FROM THE TWO LONG DURATION EVENTS. CAPE VALUES
WILL SUPPORT SOME THUNDERSTORMS WITH THIS EVENT AS WELL...BUT WILL
REMAIN ISOLATED.
RAIN SHOULD MOVE EAST OF THE AREA BY SUNDAY AND THE REST OF THE
FORECAST PERIOD SHOULD REMAIN MOSTLY DRY. THE GFS/ECMWF IS
SHOWING ANOTHER FRONT WITH POSSIBLE LIGHT RAIN MONDAY AFTERNOON
AND MONDAY NIGHT BUT WILL NOT MENTION ANYTHING AT THIS TIME DUE TO
SOME TIMING DISCREPANCIES.
HAMPSHIRE
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 73 59 73 60 76 / 60 70 60 20 20
AUSTIN BERGSTROM INTL AIRPORT 73 59 73 60 75 / 50 70 60 20 20
NEW BRAUNFELS MUNI AIRPORT 73 60 75 60 76 / 80 80 60 20 10
BURNET MUNI AIRPORT 70 57 72 58 75 / 60 70 50 20 20
DEL RIO INTL AIRPORT 70 58 77 60 81 / 50 30 20 10 10
GEORGETOWN MUNI AIRPORT 73 59 72 59 75 / 50 70 60 20 20
HONDO MUNI AIRPORT 69 59 75 60 78 / 80 70 50 10 10
SAN MARCOS MUNI AIRPORT 73 60 74 60 76 / 60 80 60 20 10
LA GRANGE - FAYETTE REGIONAL 77 62 73 62 75 / 40 60 60 20 20
SAN ANTONIO INTL AIRPORT 72 60 74 61 76 / 80 80 50 20 10
STINSON MUNI AIRPORT 72 60 75 62 77 / 80 80 50 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR THE FOLLOWING
COUNTIES: DE WITT...GONZALES...KARNES...LAVACA.
&&
$$
MESOSCALE/AVIATION...03
SYNOPTIC/GRIDS...29
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
354 AM CDT TUE MAR 17 2015
.SHORT TERM (TODAY THROUGH WEDNESDAY)...
THE ATMOSPHERE CONTINUES TO MOISTEN OVERNIGHT WITH TWO MAIN AREAS
OF SATURATION ONGOING IN THE COLUMN. FIRST IS ABUNDANT UPPER
LEVEL MOISTURE THAT CAN EASILY BE SEEN ON IR SATELLITE IMAGERY.
THE LOWER LEVELS OF THE ATMOSPHERE ARE NEARLY SATURATED AS WELL
WITH LOW CLOUDS AND SOME FOG BEING REPORTED ACROSS THE
AREA...MAINLY NEAR THE BALCONES ESCARPMENT. THE LOW-LEVEL
SATURATION IN COMBINATION WITH 25 KNOTS OF SOUTHERLY FLOW IS
LEADING TO SOME POCKETS OF LIGHT DRIZZLE. THIS SHOULD CONTINUE
THROUGH THE MORNING HOURS. WITH THE LOWER AND UPPER LEVELS OF THE
ATMOSPHERE NEARLY SATURATED...ALL THAT REMAINS IS THE MID LEVELS
WHICH REMAIN FAIRLY DRY. CURRENT RAP ANALYSIS SHOWS 700 MB RH
VALUES IN THE 20 TO 50 PERCENT RANGE ACROSS MUCH OF THE AREA.
CHANCES FOR SUBSTANTIAL RAINFALL WILL BE MINIMAL AS LONG AS THE
MID-LEVELS CONTINUE TO BE FAIRLY DRY. HOWEVER...AS THE UPPER LOW
APPROACHES THE AREA MOISTENING OF THE MID-LEVELS SHOULD OCCUR. THE
RAP IS SHOWING MOISTURE INCREASING WITHIN THE NEXT SEVERAL HOURS
WITH SATURATION AT 700 MB FOR THE WESTERN HALF OF THE AREA BY 16Z.
NOW WE KNOW WHEN THE BEST MOISTURE FOR PRECIPITATION PRODUCTION
WILL OCCUR...THE NEXT QUESTION IS WHEN WILL THE DEEP LIFT ARRIVE
TO THE AREA AND HOW LONG THE LIFTING WILL REMAIN IN PLACE.
CURRENTLY...THE CENTER OF THE UPPER LOW IS LOCATED EAST OF BAJA
ACROSS WESTERN MEXICO. LAST NIGHT THERE WERE SOME MODELS WHICH
MOVED THE CENTER OF THE LOW NEAR DEL RIO WHILE SOME MOVED THE
CENTER OF THE LOW CLOSER TO WEST TEXAS. A 00Z 500 MB ANALYSIS
GIVES US A GOOD IDEA ON THE EXPECTED TRACK. THE RIDGE AXIS HAS
SHIFTED EAST AND IS NOW CENTERED IN THE NORTHERN GULF OF
MEXICO...AND EXTENDS NNW INTO NORTH TEXAS AND OKLAHOMA. THE
BROWNSVILLE AND CORPUS CHRISTI RAOBS HAD SLIGHT HEIGHT RISES
WHICH INDICATES THE RIDGE IS SLIGHTLY STRENGTHENING OR BUILDING
WEST. UPPER AIR SITES IN WEST TEXAS AND THE PANHANDLE INDICATE
LITTLE CHANGE IN THE 500 HEIGHT AND THIS IS WHERE THE UPPER LOW
SHOULD WANT TO GO. MOST IF NOT ALL THE LATEST MODEL GUIDANCE HAS
PICKED UP ON THIS AND HAS THE LOW TRACKING ACROSS WESTERN TEXAS
LATE THIS EVENING AND OVERNIGHT.
THIS IS A SOMEWHAT UNUSUAL UPPER LOW FOR SOUTH-CENTRAL
TEXAS...GIVEN THE CURRENT POSITION IS SO FAR TO THE SOUTH. WITH
THE LOW MOVING TO THE NNE THE BEST POTENTIAL VORTICITY ADVECTION
WILL BE JUST TO OUR NORTHWEST. HOWEVER...A BAND OF LOW- LEVEL
CONFLUENCE SHOULD SET UP NEAR THE HIGHWAY 83 CORRIDOR BY THE LATE
MORNING HOURS. THIS FEATURE IN COMBINATION WITH THE SOME UPPER
SUPPORT WILL LEAD TO AN AREA OF HIGHER RAINFALL. AT THE PRESENT
TIME...IT LOOKS LIKE THIS BAND OF HEAVIER RAIN WILL INITIALLY FALL
BETWEEN THE HIGHWAY 83 AND I-35/37 CORRIDOR BEGINNING AROUND MIDDAY
ONCE THE MID-LEVELS OF THE ATMOSPHERE SATURATE. WITH THE UPPER LOW
MOVING MORE NORTH THAN EAST...THIS ZONE OF N-S LIFT WILL BE SLOW
TO SHIFT EAST BUT WILL SLOWLY DO SO THIS AFTERNOON THROUGH THE
EVENING...EVENTUALLY MAKING IT EAST OF THE I-35/37 CORRIDOR. WILL
SHOW THIS EXPECTED PROGRESSION IN THE POP FORECAST.
AFTER THIS INITIAL AREA OF RAINFALL DEVELOPS AND MOVES EAST...THE
FOCUS THEN SHIFTS ON ANY ADDITIONAL ACTIVITY OVERNIGHT TUESDAY.
THE ECMWF IS FORECASTING AN ENHANCED VORT MAX ROTATING ON THE
SOUTHERN PERIPHERY OF THE UPPER LOW...MOVING INTO THE CWA. THE
GFS/NAM ARE MUCH WEAKER WITH THIS FEATURE. UNFORTUNATELY OUR ONLY
CLUE TO THIS FEATURE WOULD BE LOOKING AT WATER VAPOR IMAGERY.
THERE DOES SEEM TO BE AN ENHANCEMENT CURRENTLY ON THE BACKSIDE OF
THE LOW...BUT IT IS DIFFICULT TO ASCERTAIN IF THIS IS WHAT THE
ECMWF IS PICKING UP ON. THINK THE MOST LIKELY SCENARIO IS WHAT THE
GFS/NAM ARE SHOWING AND THAT IS INCREASED ISENTROPIC ASCENT
DEVELOPING OVERNIGHT...LEADING TO MAINLY SCATTERED TO NUMEROUS
ACTIVITY. THERE SHOULD BE ENOUGH ACTIVITY IN THE OVERNIGHT HOURS
TO WARRANT ANOTHER PERIOD OF LIKELY POPS. WEAK LIFT WILL OCCUR FOR
THE EASTERN HALF ON WEDNESDAY AND WILL CONTINUE WITH DECENT POPS
IN THE FORECAST.
FORECAST SOUNDINGS CONTINUE TO SHOW WEAK INSTABILITY AND WILL
MENTION ISOLATED THUNDER. REGARDING RAINFALL TOTALS...THE
PREVIOUSLY MENTIONED AREA WHERE THE ENHANCED RAINFALL WILL OCCUR
SHOULD SEE AN AVERAGE OF 1 TO 1.5 INCHES THROUGH WEDNESDAY. THE
LACK OF SURFACE FOCUS WITH A BOUNDARY SHOULD LIMIT RAINFALL
TOTALS OVERALL AS ACTIVITY WILL BE SLIGHTLY ELEVATED. HOWEVER...
IF THE ECMWF VERIFIES WITH ITS REGENERATION TUESDAY NIGHT...THE
TOTALS COULD GO UP ANOTHER HALF AN INCH OR SO. THIS AREA DID NOT
SEE AS MUCH WITH THE LAST EVENT AND CAN EASILY TAKE THESE TOTALS.
HOWEVER...WILL MENTION LOCALLY HEAVY RAINFALL IN THE HWO AND
GRAPHICS TO ACCOUNT FOR ANY SLIGHTLY HIGHER RAINFALL TOTALS OR
POSSIBLE EASTWARD SHIFT WITH THE HEAVIEST BAND OF RAIN TO AREA
WHERE HEAVIER RAIN DID FALL LAST WEEK.
&&
.LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...
SLIGHT CHANCE POPS WILL CONTINUE ACROSS THE NORTHERN AND EASTERN
AREAS WEDNESDAY NIGHT AND THURSDAY...BUT NOT EXPECTING ANY
WIDESPREAD ACTIVITY IN THIS TIME FRAME. THIS PERIOD WILL SERVE AS
A TRANSITION BETWEEN UPPER LOWS. THE NEXT UPPER LOW WILL APPROACH
THE AREA ON FRIDAY. AT THE SAME TIME A TROUGH WILL PASS THROUGH
THE CENTRAL PLAINS SENDING A COLD FRONT THROUGH THE CWA ON FRIDAY.
THE UPPER SUPPORT WITH THIS SYSTEM WILL BE COMBINED WITH A SURFACE
BOUNDARY INITIALLY...BUT THIS FOCUS WILL QUICKLY BE LOST AS THE
FRONT MOVES INTO SOUTH TEXAS. RAIN WILL CONTINUE POST FRONTAL
THROUGH SATURDAY AS THE UPPER LOW REMAINS TO THE WEST OF THE AREA
AND WARMER AIR IS LIFTED ON TOP OF THE FRONTAL INVERSION. THERE
STILL APPEARS TO BE A CHANCE THE 850 FRONT MAKES IT TO THE AREA
AND THIS COULD SERVE AS AN ENHANCEMENT IN THE LIFT LEADING TO A
BAND OF HEAVIER TOTALS FALLING SOMEWHERE IN THE REGION. IT IS
STILL TOO EARLY TO GET INTO THE SPECIFICS REGARDING WHERE THIS
WILL OCCUR. PW VALUES WILL BE SLIGHTLY HIGHER WITH THIS EVENT AS
WELL. FLOODING POTENTIAL IS THERE WITH THIS SECOND EVENT BUT SOME
OF IT WILL DEPEND ON HOW MUCH RAIN FALLS FROM THE FIRST EVENT AND
WHERE. THE FLOOD POTENTIAL WOULD PRIMARILY BE TO RIVERS FROM
EXCESSIVE RUNOFF FROM THE TWO LONG DURATION EVENTS. CAPE VALUES
WILL SUPPORT SOME THUNDERSTORMS WITH THIS EVENT AS WELL...BUT WILL
REMAIN ISOLATED.
RAIN SHOULD MOVE EAST OF THE AREA BY SUNDAY AND THE REST OF THE
FORECAST PERIOD SHOULD REMAIN MOSTLY DRY. THE GFS/ECMWF IS
SHOWING ANOTHER FRONT WITH POSSIBLE LIGHT RAIN MONDAY AFTERNOON
AND MONDAY NIGHT BUT WILL NOT MENTION ANYTHING AT THIS TIME DUE TO
SOME TIMING DISCREPANCIES.
HAMPSHIRE
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 73 59 73 60 76 / 60 70 60 20 20
AUSTIN BERGSTROM INTL AIRPORT 73 59 73 60 75 / 50 70 60 20 20
NEW BRAUNFELS MUNI AIRPORT 73 60 75 60 76 / 80 80 60 20 10
BURNET MUNI AIRPORT 70 57 72 58 75 / 60 70 50 20 20
DEL RIO INTL AIRPORT 70 58 77 60 81 / 50 30 20 10 10
GEORGETOWN MUNI AIRPORT 73 59 72 59 75 / 50 70 60 20 20
HONDO MUNI AIRPORT 69 59 75 60 78 / 80 70 50 10 10
SAN MARCOS MUNI AIRPORT 73 60 74 60 76 / 60 80 60 20 10
LA GRANGE - FAYETTE REGIONAL 77 62 73 62 75 / 40 60 60 20 20
SAN ANTONIO INTL AIRPORT 72 60 74 61 76 / 80 80 50 20 10
STINSON MUNI AIRPORT 72 60 75 62 77 / 80 80 50 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...03
SYNOPTIC/GRIDS...29
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1143 AM MDT TUE MAR 17 2015
.UPDATE...
ISSUED AT 1121 AM MDT TUE MAR 17 2015
WYDOT WEBCAMS SHOW NO IMPROVEMENT IN THE FOG/DRIZZLE SITUATION
LATE THIS MORNING. IN FACT...CONDITIONS HAVE ACTUALLY WORSENED
EASTWARD INTO CHEYENNE. HRRR AND RAP FORECAST SOUNDINGS SUGGEST
SOME DRYING NEAR THE SURFACE IN THE NEXT FEW HOURS...SO BELIEVE
VISIBILITIES WILL IMPROVE BY EARLY AFTERNOON. DECIDED TO ADD CYS
TO THE DENSE FOG ADVISORY AND EXTEND ALL ZONES UNTIL 19Z. LATEST
VISIBLE SATELLITE IMAGERY SHOWS WIDESPREAD LOW/MID CLOUDS ACROSS
THE CWA. WITH PERSISTENT MOIST SOUTH-TO-SOUTHEAST BOUNDARY LAYER
FLOW THROUGH PEAK HEATING...CLOUDS WILL BE SLOW TO ERODE AND OUR
RESULTING HIGHS SHOULD BE MUCH COOLER THAN PREVIOUSLY FCST. HAVE
LOWERED HIGHS 5-10 DEGREES ACROSS THE BOARD.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 405 AM MDT TUE MAR 17 2015
TODAY...LOOKING AT WYOMING DEPARTMENT OF TRANSPORTATION WEBCAMS...
OUR DENSE FOG ADVISORY FOR THE SOUTHERN LARAMIE RANGE AND SOUTHERN
LARAMIE RANGE FOOTHILLS...INCLUDING THE INTERSTATE 80 SUMMIT BETWEEN
LARAMIE AND CHEYENNE...IS WORKING OUT WELL. LOOKS LIKE DENSE FOG AT
ALMOST ALL OF THE SUMMIT WEBCAMS...AND THIS QUITE UNDERSTANDABLE
WITH 330 AM CEILINGS AT LARAMIE AND CHEYENNE AT 900 FEET AND 500
FEET AGL...RESPECTIVELY AND SOUTHEAST WINDS AROUND 30 MPH AT LARAMIE
AS THE COLD SHALLOW AIR FUNNELS THROUGH THE SUMMIT AND INTO THE
LARAMIE VALLEY. THUS...WILL CONTINUE THE DENSE FOG ADVISORY THROUGH
9 AM. TEMPERATURE AND DEWPOINT SPREADS ELSEWHERE RANGE FROM 2 TO 5
DEGREES FAHRENHEIT...AND WITH DECENT MIXING...AREAS OF FOG IN THE
GRIDDED FORECASTS WILL LIKELY SUFFICE THROUGH MID MORNING.
RIDGING ALOFT STRENGTHENS TODAY WITH RETURN SOUTHEAST WINDS. WITH
COOL AIR CONTINUING EAST OF THE LARAMIE RANGE...MAXIMUM TEMPERATURES
WILL BE IN THE LOW TO MID 50S...WHEREAS...WEST OF THE LARAMIE
RANGE...TEMPERATURES WILL WARM INTO THE UPPER 50S TO MID 60S WHERE
COLD AIR WILL BE EITHER NON-EXISTENT OR SCOURED OUT ACROSS THE
LARAMIE VALLEY.
TONIGHT...WEAK LOW AMPLITUDE SHORTWAVE TROUGH ALOFT MOVES ACROSS
MONTANA AND NORTHERN WYOMING WITH A SURFACE TROUGH DEVELOPING ALONG
INTERSTATE 25. WITH LIMITED LOW AND MID LEVEL MOISTURE AND DOWNWARD
VERTICAL MOTION...ONLY A FEW ISOLATED SNOW SHOWERS EXPECTED ACROSS
THE SNOWY AND SIERRA MADRE RANGES.
WEDNESDAY...RELATIVELY WEAK SHORTWAVE TROUGH ALOFT MOVES ACROSS
COLORADO WITH THE BEST UPWARD VERTICAL MOTION AND DEEPEST LOW AND
MID LEVEL MOISTURE OVER COLORADO WHERE MOST OF THE SNOW WILL FALL.
HOWEVER...LOOKS LIKE ENOUGH OROGRAPHICS AND SOME WEAK DYNAMICS TO
PRODUCE A SCATTERED COVERAGE OF SNOW SHOWERS OVER OUR SNOWY...SIERRA
MADRE AND SOUTHERN LARAMIE RANGE MOUNTAINS...DRY ELSEWHERE.
WEDNESDAY NIGHT...POSITIVELY TILTED SHORTWAVE TROUGH ALOFT...THE
NORTHERN STREAM SHORTWAVE...MOVES INTO WESTERN WYOMING...WITH BEST
700-500 MB AND 500-300 MB QUASIGEOSTROPHIC LIFT ACROSS SOUTHERN
WYOMING AND COMBINED WITH ENOUGH LOW AND MID LEVEL MOISTURE...WILL
SEE A 20 TO 40 PERCENT COVERAGE OF LIGHT SNOW WITH MINIMAL
ACCUMULATIONS LIKELY DUE TO LOW QPF. BOUNDARY LAYER PROGS SUGGEST
ARES OF FOG ALONG AND WEST OF THE LARAMIE RANGE...ESPECIALLY WHERE
AREAL PRECIPITATION COVERAGE IS LESS.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 405 AM MDT TUE MAR 17 2015
THE SHORTWAVE TROUGH WILL MOVE OVER THE FORECAST AREA ON THURSDAY
IN NORTHWEST FLOW...ALONG WITH A WEAK SFC BOUNDARY. A FEW SHOWERS
ARE PROGGED TO CONTINUE IN THE MORNING AND EARLY AFTERNOON AS THE
TROUGH MOVES THROUGH...WITH THE FOCUS FOR DEVELOPMENT LOOKING TO
BE OVER THE MOUNTAINS AND ALONG THE CHEYENNE RIDGE. OVERALL
DEVELOPMENT WILL BE MINIMAL THO WITH JET SUBSIDENCE AND MARGINAL
MOISTURE OVERHEAD. TEMPS ARE LOOKING TO BE ROUGHLY 5 TO 10 DEGREES
COOLER ON THURSDAY COMPARED TO WEDNESDAY...BUT WILL STILL FAVOR
RAIN SHOWERS ACROSS THE PLAINS WITH SNOW OR A MIX OF RAIN-SNOW IN
SHOWERS THAT DEVELOP IN THE HIGH COUNTRY. TEMPS WILL REBOUND
QUICKLY ON FRIDAY AND SATURDAY AS THE UPPER RIDGE BUILDS BACK OVER
THE ROCKIES IN THE WAKE OF THE TROUGH. A VERY DRY AIRMASS WILL
ACCOMPANY THE RIDGE ALONG WITH BROADSCALE SUBSIDENCE...AND SKIES
ARE EXPECTED TO BE MOSTLY CLEAR THROUGH THIS TIME. MODELS SHOW
ANOTHER WEAK SFC TROUGH SLIDING SOUTHEAST ACROSS THE HIGH PLAINS
FRIDAY MORNING WITH THE MAIN IMPACT TO BE BREEZY WEST-NORTHWEST
WINDS IN ITS WAKE. WILL HAVE TO KEEP AN EYE OUT FOR ELEVATED FIRE
WEATHER CONCERNS WITH THE COMBINATION OF DRY AND BREEZY
CONDITIONS. WINDS WILL BE LESS ON SATURDAY AS THE SFC TROUGH
SETTLES NW-SE ACROSS THE HIGH PLAINS.
MODELS ARE IN SLIGHTLY BETTER AGREEMENT WITH THE NEXT SHORTWAVE
TROUGH PROGGED TO MOVE EAST ACROSS THE NORTHERN ROCKIES ON
SUNDAY...HOWEVER STILL DIFFER WITH INTENSITY AND TIMING OF THE
EMBEDDED VORTICITY AND THUS OVERALL EVOLUTION OF THE SYSTEM. WILL
MAINTAIN MAINLY SLIGHT CHANCE POPS DUE TO THE CONTINUED
UNCERTAINTY WITH THIS SYSTEM...WITH THE BEST AREA FOR DEVELOPMENT
EXPECTED OVER THE MOUNTAINS AND ALONG THE STALLED SFC TROUGH.
SHOWERS COULD REDEVELOP ALONG THIS FEATURE UNTIL IT PUSHES
SOUTHEAST SUNDAY NIGHT INTO MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1121 AM MDT TUE MAR 17 2015
WITH PERSISTENT SOUTHERLY WINDS CONTINUING AT CYS...EXPECT FOG AND
LIFR CONDITIONS TO PERSIST THROUGH 20-21Z. VFR CIGS WITH BASES
4-7 THOUSAND FEET WILL OCCUR OVER THE NEBRASKA PANHANDLE.
SUBSTANTIAL CLEARING WILL OCCUR AT SITES TO THE EAST OF THE
LARAMIE RANGE BY LATER THIS AFTERNOON. SOUTHEASTERLY WINDS WILL
GUST TO 25 KTS OVER THE PANHANDLE THROUGH EARLY TONIGHT.
&&
.FIRE WEATHER...
ISSUED AT 405 AM MDT TUE MAR 17 2015
NO FIRE WEATHER CONCERNS THROUGH THURSDAY DUE TO RELATIVELY HIGH
HUMIDITIES. FIRE WEATHER CONCERNS WILL HEIGHTEN FRIDAY AND
SATURDAY AS AFTERNOON HUMIDITIES FALL INTO THE 15 TO 25 PERCENT
RANGE. A COOLER AIRMASS WILL INCREASE HUMIDITIES SUNDAY AND
MONDAY...AND LESSEN FIRE WEATHER CONCERNS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...DENSE FOG ADVISORY UNTIL 1 PM MDT THIS AFTERNOON FOR WYZ116>118.
NE...NONE.
&&
$$
UPDATE...CLH
SHORT TERM...RUBIN
LONG TERM...RJM
AVIATION...ZF
FIRE WEATHER...RUBIN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
235 AM MST THU MAR 19 2015
.SYNOPSIS...
CLOUDY CONDITIONS AND COOLER TEMPERATURES WILL BE IN OUR AREA
THROUGH TODAY. SOME LIGHT SHOWERS WITH EVEN A RUMBLE OF THUNDER MAY
BE SEEN. A DRYING...AND WARMING TREND WILL BE SEEN BEGINNING FRIDAY
AND CONTINUING INTO THE MIDDLE PART OF NEXT WEEK.
&&
.DISCUSSION...
TODAY TROUGH FRIDAY... A RATHER UNSETTLED PATTERN CONTINUES THIS
MORNING ACROSS OUR CWA. CURRENT RADAR AND SATELLITE IMAGERY
CONTINUES TO SHOW SCATTERED-NUMEROUS SHOWERS ACROSS MUCH OF
ARIZONA...WITH EVEN A FEW THUNDERSTORMS ACROSS SOUTHWEST
ARIZONA...WHICH HAS LIKELY BROUGHT UP TO A HALF INCH...OR EVEN A
LITTLE MORE TO A FEW ISOLATED SPOTS. THE COMPLEX UPPER LOW CENTER
THAT HAS BROUGHT US THIS WET WEATHER IS NOW CENTERED OVER EXTREME
NORTHERN BAJA...AND IS FORECAST TO MOVE SLOWLY EASTWARD JUST SOUTH
OF THE INTERNATIONAL BORDER OVER THE NEXT 48-72 HOURS. THE FOCUS OF
THE HEAVIEST RAINFALL OVER THE LAST 6-9 HOURS HAS BEEN OVER LA
PAZ...NORTHERN YUMA...AND EXTREME WESTERN MARICOPA...AS A SPOKE OF
VORTICITY ROTATES SLOWLY WESTWARD AROUND THE MAIN LOW CENTER.
LIGHTER SHOWER ARE ALSO BEING OBSERVED AT THIS TIME ACROSS THE
REMAINDER OF MARICOPA COUNTY AS WELL...BUT RAINFALL AMOUNTS OVER THE
PAST FEW HOURS IN THAT REGION HAVE BEEN PRETTY MEAGER...MAINLY IN
THE TRACE-0.05 INCH RANGE...AS THERE HAS BEEN A BIT OF
DRYSLOTING/LOSS OF VERTICAL MOTION BEHIND THE AFOMENTIONED VORTICITY
LOBE. THE LATEST HRRR AND NAM SHORT-RANGE MODELS ARE NOW INDICATING
THAT THE HEAVIEST SHOWERS WILL LIKELY CONTINUE ACROSS SOUTHWEST AZ
AND NORTHWEST MARICOPA COUNTY...AND EVEN MOVE BACK INTO PASTS OF SE
CA BETWEEN NOW AND 18Z...THEN SHIFT BACK EASTWARD INTO MARICOPA/GILA
COUNTIES BETWEEN 18-00Z AS ANOTHER WEAK SHORTWAVE/COLD POOL ROTATES
AROUND THE MAIN LOW CENTER. ISOLATED THUNDERSTORMS WILL LIKELY
DEVELOP AGAIN THIS AFTERNOON AS SOLAR HEATING AND SLIGHTLY COLDER
AIR ALOFT DESTABILIZE THE COLUMN. A DRYING TREND IS THEN EXPECTED TO
BEGIN TO WORK ITS WAY EASTWARD ACROSS THE REGION THIS EVENING AS THE
MAIN TROF AXIS SHIFTS SLOWLY OFF TO THE EAST AND PWATS BEGIN TO
DROP...WITH MOST OF THE SHOWER ACTIVITY SHIFTING INTO SOUTHERN GILA
COUNTY BY LATE TONIGHT. FRIDAY WILL SEE MORE ISOLATED-SCATTERED
SHOWER ACTIVITY ACROSS SOUTHERN GILA COUNTY AS A BIT OF MOISTURE IS
WRAPPED BACK WESTWARD INTO THAT REGION. THE CLOUDS AND SHOWERS WILL
HOLD TEMPERATURES WELL INTO THE 70S ACROSS THE LOWER DESERTS OF
SOUTH-CENTRAL ARIZONA...WITH SOME LOW 80S ACROSS SW AZ AND SE
CA...WITH SOME MODEST WARMING ON FRIDAY AS SKIES BEGIN TO CLEAR
SATURDAY THROUGH THURSDAY...A WARMING AND DRYING TREND STILL APPEARS
ON TAP FROM SATURDAY ONWARD INTO AT LEAST THE MIDDLE OF NEXT WEEK AS
BOTH THE GFS AND EURO MODELS CONTINUE TO BUILD FLAT RIDGING BACK
OVER THE REGION AS THE AFOREMENTIONED UPPER TROF MOVES OFF WELL TO
OUR EAST...WITH LOWER DESERT HIGHS LIKELY REACHING 90 DEGREES BY
EARLY NEXT WEEK. SOME COOLING IS POSSIBLE BY THE END OF NEXT WEEK AS
THE NEXT MAJOR LOW-WAVE TROF BRUSHES BY WELL TO OUR NORTH AND EAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
THICK MIDLEVEL CIGS WILL PREVAIL THROUGH THURSDAY
AFTERNOON...POTENTIALLY BRIEFLY TOUCHING AS LOW AS 6K-8K FT LATE
THURSDAY MORNING. VERY LIGHT SHOWERS/SPRINKLES WILL CONTINUE INTO
THE NIGHT...HOWEVER SHOULD NOT AMOUNT TO MUCH MORE THAN A TRACE AND
PROVIDE MINIMAL IMPACT. ONLY MODERATE CONFIDENCE IN ANY WIND SHIFTS
THROUGH THURSDAY MORNING...THOUGH DIRECTIONS SHOULD FAVOR AN
EASTERLY COMPONENT.
MORE SCATTERED SHOWERS AND POTENTIALLY A FEW ISOLATED THUNDERSTORMS
WILL BE POSSIBLE THURSDAY AFTERNOON. GUSTY WIND SHIFTS MAY ACCOMPANY
ANY STORMS...WHICH WOULD BE MOST LIKELY AFTER 20Z. HAVE NOT INCLUDED
THUNDER MENTION IN TAFS GIVEN THE UNCERTAIN COVERAGE AT THIS TIME.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
EXTENSIVE THICK CIGS IN AN 8K-12K FT RANGE WILL ONLY BEGIN TO SCATTER
THURSDAY AFTERNOON. SHOWERS WILL BE MOST PREVALENT AT KBLH TONIGHT
CAUSING SHIFTING WINDS...LOWERING CIGS POTENTIALLY DOWN TO 6K
FT...AND POSSIBLY BRIEF PERIODS OF LOWER VISIBILITIES. CONFIDENCE IS
LOW THAT FLIGHT CATEGORIES WOULD BE REDUCED...THOUGH NOT OUT OF THE
REALM OF POSSIBILITY. SHOWERS MAY BE POSSIBLE AGAIN FOR A SHORT
PERIOD THURSDAY AFTERNOON...THOUGH CONDITIONS SHOULD RAPIDLY IMPROVE
BY SUNSET.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...A DRYING TREND IS EXPECTED THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. EXPECT MINIMUM HUMIDITY LEVELS TO DROP
INTO THE LOWER TEENS OVER THE WEEKEND UNDER MOSTLY SUNNY SKIES.
LINGERING ISOLATED SHOWERS ARE POSSIBLE OVER THE HIGH TERRAIN EAST
OF PHOENIX THROUGH SATURDAY...BUT TEMPERATURES WILL STEADILY CLIMB
DURING THE PERIOD WITH THE WARMER DESERTS REACHING THE UPPER 80 TO
AROUND 90S BY EARLY NEXT WEEK. NO SIGNIFICANT WIND IS EXPECTED
THROUGH MONDAY...JUST SOME AFTERNOON UPSLOPE GUSTS FAVORING THE WEST
EACH DAY. INCREASING WEST WIND IS LIKELY TUESDAY WITH GUSTS IN
EXCESS OF 25 MPH POSSIBLE.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA
AVIATION...MO
FIRE WEATHER...CB/MEYERS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
230 AM MST THU MAR 19 2015
.SYNOPSIS...SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL BE AROUND
THROUGH FRIDAY EVENING. DRY CONDITIONS WILL RETURN THIS WEEKEND
EXCEPT FOR A FEW LINGERING SHOWERS ACROSS THE WHITE MOUNTAINS
SATURDAY. COOLER DAYTIME TEMPERATURES TODAY AND FRIDAY THEN A
WARMING TREND THIS WEEKEND INTO EARLY NEXT WEEK.
&&
.DISCUSSION...WIDESPREAD RAIN YESTERDAY WITH AMOUNTS RANGING FROM
0.01" TO 0.90". THIS WET WEATHER IS FORECAST TO CONTINUE TODAY INTO
FRIDAY BEFORE TURNING DRY FOR THE WEEKEND INTO NEXT WEEK.
AT 2 AM...DOPPLER RADAR SHOWED ISOLATED LIGHT SHOWERS EAST OF TUCSON
AND UP TOWARD PHOENIX. THE REST OF THE AREA WAS DRY AS SHORT WAVE
MOVES NORTH INTO CENTRAL AZ. OVERALL THE MAIN UPPER LEVEL TROF IS
STILL TO OUR WEST AND WILL SLOWLY MOVE EAST TODAY INTO FRIDAY
KEEPING SHOWER ACTIVITY GOING NEXT COUPLE OF DAYS. FOR THE SHORT
TERM A FEW THUNDERSTORMS DEVELOPED BETWEEN MIDNIGHT AND 1 AM NEAR
HERMOSILLO SONORA AND THE LATEST HRRR RUNS CAPTURED THIS NICELY AND
SPREAD THESE STORMS NNE TOWARD COCHISE COUNTY. RAINFALL AMOUNTS THRU
FRIDAY AFTERNOON ARE FORECAST TO RANGE BETWEEN 0.05" TO 0.50" IN THE
VALLEYS TO NEAR 1" IN THE MOUNTAINS. SNOW LEVEL WILL MOSTLY REMAIN
ABOVE THE TIPS BUT OCCASIONALLY FALL DOWN TO 9000 FEET. HIGH TODAY
AND FRIDAY WILL BE AT OR SLIGHTLY BELOW NORMAL.
A FEW LINGERING SHOWERS FAR EASTERN AREAS SATURDAY AS HIGH PRESSURE
BUILDS IN FROM THE WEST. FLAT RIDGE OVER THE AREA SUNDAY THROUGH
NEXT WEDNESDAY RESULTING IN A WARMING TREND.
&&
.AVIATION...VALID THRU 20/12Z.
BKN-OVC CLOUDS AT 6-10K FT AGL AND ISOLD-SCT -SHRA/-TSRA THRU THE
FORECAST PERIOD. BRIEF MVFR CONDITIONS POSSIBLE WITH THE STRONGEST
-SHRA/-TSRA...HOWEVER MOST LOCATIONS WILL HAVE VFR CONDITIONS.
SURFACE WIND LESS THAN 10 KTS THRU 19/18Z AND AGAIN AFT 20/02Z.
SURFACE WIND BETWEEN 19/18Z AND 20/02Z...WLY/NWLY AT 8-15 KTS. GUSTY
WINDS POSSIBLE NEAR THUNDERSTORMS...WITH GUSTS TO NEAR 35 KTS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...AN AREA OF LOW PRESSURE OVER THE NORTHERN BAJA
PENINSULA WILL MOVE SLOWLY EAST ACROSS THE REGION TODAY AND
FRIDAY...PUSHING EAST OF THE AREA SATURDAY. THIS SYSTEM WILL RESULT
IN A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS MUCH OF SOUTHEAST
ARIZONA TODAY...ACROSS THE EASTERN HALF OF SOUTHEAST ARIZONA ON
FRIDAY...AND MAINLY IN THE WHITE MOUNTAINS SATURDAY. DRY CONDITIONS
WILL THEN RETURN LATE THIS WEEKEND AND CONTINUE INTO THE MIDDLE OF
NEXT WEEK. GUSTY AND ERRATIC WINDS MAY OCCUR NEAR THUNDERSTORMS.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
1040 PM PDT WED MAR 18 2015
.UPDATE...REMOVED SHOWERS FROM THE SIERRA ZONES FOR TONIGHT AND
REVISED THE AVIATION DISCUSSION.
.SYNOPSIS...A WEAK STORM SYSTEM OFF THE COAST OF NORTHERN BAJA
WILL BRING A FEW RESIDUAL SHOWERS TO THE KERN COUNTY DESERT
TONIGHT. DRY WEATHER WILL PREVAIL ELSEWHERE AS A RIDGE OF HIGH
PRESSURE BUILDS IN FROM THE NORTH. THE RIDGE WILL BRING CLEAR
SKIES AND ABOVE NORMAL AFTERNOON TEMPERATURES TO THE DISTRICT
THURSDAY THROUGH FRIDAY.
&&
.DISCUSSION...UPPER LEVEL LOW CONTINUES TO SPIN ITS WHEELS OFF THE
COAST OF NORTHERN BAJA THIS EVENING. ALTHOUGH SHOWER ACTIVITY
DIMINISHED SHORTLY AFTER SUNSET IN THE MOUNTAINS...RADAR IS STILL
PICKING UP SOME LIGHT RAIN IN THE KERN COUNTY DESERT AS MOISTURE
WRAPS AROUND THE UPPER LEVEL LOW IN THE NORTHEAST FLOW ALOFT.
FARTHER NORTH AND WEST...MOISTURE IS HIGH BASED WITH A THIN VEIL
OF CIRRUS EXTENDING NORTHWARD TO FRESNO COUNTY.
A DRIER AIR MASS WILL SETTLE OVER THE CENTRAL CA INTERIOR TONIGHT
AND THURSDAY AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS IN
FROM THE NORTH. THE RIDGE WILL DOMINATE OUR PATTERN THROUGH FRIDAY
BEFORE GETTING FLATTENED BY A WEAK SHORT WAVE TROUGH THAT TREKS
EASTWARD ACROSS THE NORTHERN PART OF THE STATE SATURDAY. THE
MODELS FORECAST A ZONAL FLOW ALOFT TO RESIDE OVER CENTRAL CA IN
THE 3 TO 7 DAY PERIOD. A SERIES OF WEAK UPPER LEVEL DISTURBANCES
WILL TRACK THROUGH THE PAC NW NEXT WEEK. ONE OF THESE SYSTEMS
COULD BRUSH YNP WITH SOME LIGHT PRECIP MONDAY INTO MONDAY NIGHT
BUT IT IS A VERY LOW CHANCE AT THIS POINT. OTHERWISE...DRY
WEATHER WILL PREVAIL THROUGHOUT THE CENTRAL CA INTERIOR FOR
THE NEXT 7 DAYS.
&&
.PREV DISCUSSION... /ISSUED 233 PM PDT WED MAR 18 2015/
DISCUSSION...PER LATEST HRRR GUIDANCE...ADDED IN SOME SLIGHT
CHANCE POPS IN SJ VALLEY IN TULARE COUNTY INCLUDING AS FAR WEST AS
VISALIA AND TULARE. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN
HIGHER ELEVATIONS OF SIERRA NEVADA MAINLY IN TULARE AND FRESNO
COUNTIES AROUND WET MEADOWS AND UPPER BURNT CORRAL. STEERING FLOWS
OF SIERRA THUNDERSTORMS ARE MAINLY FROM NORTHEAST AND COULD
GENERATE SHOWERS AND THUNDERSTORMS LOWER OVER FOOTHILLS OVER NEXT
FEW HOURS...OR THRU AROUND SUNSET.
&&
.AVIATION...
AREAS OF MVFR CONDITIONS OVER THE SIERRA NEVADA AND TEHACHAPI RANGE
THROUGH 16Z THURSDAY. A SHOWER MAY STILL BE POSSIBLE ACROSS THE KERN
COUNTY DESERT THROUGH 12Z THURSDAY. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CENTRAL CA INTERIOR FOR THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 03-18 87:2004 50:1991 57:1910 32:1898
KFAT 03-19 86:1928 50:1894 58:1916 32:1898
KFAT 03-20 89:1960 52:1897 59:1896 33:1982
KBFL 03-18 92:2004 51:1919 58:2004 23:1900
KBFL 03-19 90:1928 49:1919 60:1934 31:1903
KBFL 03-20 93:2004 52:1919 59:1909 32:1935
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...DURFEE
AVN/FW...MOLINA
PREV DISCUSSION...BSO
SYNOPSIS...DURFEE
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
1034 PM PDT WED MAR 18 2015
.UPDATE...REMOVED SHOWERS FROM THE SIERRA ZONES FOR TONIGHT.
.SYNOPSIS...A WEAK STORM SYSTEM OFF THE COAST OF NORTHERN BAJA
WILL BRING A FEW RESIDUAL SHOWERS TO THE KERN COUNTY DESERT
TONIGHT. DRY WEATHER WILL PREVAIL ELSEWHERE AS A RIDGE OF HIGH
PRESSURE BUILDS IN FROM THE NORTH. THE RIDGE WILL BRING CLEAR
SKIES AND ABOVE NORMAL AFTERNOON TEMPERATURES TO THE DISTRICT
THURSDAY THROUGH FRIDAY.
&&
.DISCUSSION...UPPER LEVEL LOW CONTINUES TO SPIN ITS WHEELS OFF THE
COAST OF NORTHERN BAJA THIS EVENING. ALTHOUGH SHOWER ACTIVITY
DIMINISHED SHORTLY AFTER SUNSET IN THE MOUNTAINS...RADAR IS STILL
PICKING UP SOME LIGHT RAIN IN THE KERN COUNTY DESERT AS MOISTURE
WRAPS AROUND THE UPPER LEVEL LOW IN THE NORTHEAST FLOW ALOFT.
FARTHER NORTH AND WEST...MOISTURE IS HIGH BASED WITH A THIN VEIL
OF CIRRUS EXTENDING NORTHWARD TO FRESNO COUNTY.
A DRIER AIR MASS WILL SETTLE OVER THE CENTRAL CA INTERIOR TONIGHT
AND THURSDAY AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS IN
FROM THE NORTH. THE RIDGE WILL DOMINANT OUR PATTERN THROUGH FRIDAY
BEFORE GETTING FLATTENED BY A WEAK SHORT WAVE TROUGH THAT TREKS
EASTWARD ACROSS THE NORTHERN PART OF THE STATE SATURDAY. THE
MODELS FORECAST A ZONAL FLOW ALOFT TO RESIDE OVER CENTRAL CA IN
THE 3 TO 7 DAY PERIOD. A SERIES OF WEAK UPPER LEVEL DISTURBANCES
WILL TRACK THROUGH THE PAC NW NEXT WEEK. ONE OF THESE SYSTEMS
COULD BRUSH YNP WITH SOME LIGHT PRECIP MONDAY INTO MONDAY NIGHT
BUT IT IS A LONG SHOT AT THIS POINT. OTHERWISE...DRY WEATHER WILL
PREVAIL THROUGHOUT THE CENTRAL CA INTERIOR DURING THE NEXT 7 DAYS.
&&
.PREV DISCUSSION... /ISSUED 233 PM PDT WED MAR 18 2015/
DISCUSSION...PER LATEST HRRR GUIDANCE...ADDED IN SOME SLIGHT
CHANCE POPS IN SJ VALLEY IN TULARE COUNTY INCLUDING AS FAR WEST AS
VISALIA AND TULARE. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN
HIGHER ELEVATIONS OF SIERRA NEVADA MAINLY IN TULARE AND FRESNO
COUNTIES AROUND WET MEADOWS AND UPPER BURNT CORRAL. STEERING FLOWS
OF SIERRA THUNDERSTORMS ARE MAINLY FROM NORTHEAST AND COULD
GENERATE SHOWERS AND THUNDERSTORMS LOWER OVER FOOTHILLS OVER NEXT
FEW HOURS...OR THRU AROUND SUNSET.
&&
.AVIATION...
AREAS OF MVFR AND LOCAL IFR IN MOUNTAIN OBSCURATIONS 19Z WED THRU
06Z THU OVER THE SOUTHERN SIERRA NEVADA AND KERN COUNTY MOUNTAINS
WITH ISOLATED THUNDERSTORMS POSSIBLE. A FEW THUNDERSTORMS ALSO
POSSIBLE IN THE KERN COUNTY DESERT. OTHERWISE...VFR CONDITIONS WILL
PREVAIL ACROSS THE CENTRAL CA INTERIOR FOR THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 03-18 87:2004 50:1991 57:1910 32:1898
KFAT 03-19 86:1928 50:1894 58:1916 32:1898
KFAT 03-20 89:1960 52:1897 59:1896 33:1982
KBFL 03-18 92:2004 51:1919 58:2004 23:1900
KBFL 03-19 90:1928 49:1919 60:1934 31:1903
KBFL 03-20 93:2004 52:1919 59:1909 32:1935
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...DURFEE
AVN/FW...MOLINA
PREV DISCUSSION...BSO
SYNOPSIS...DURFEE
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
415 AM CDT THU MAR 19 2015
.SHORT TERM...
A WARM AND MUGGY NIGHT WILL GIVE WAY TO ANOTHER WARM SPRING DAY
FOR THE FORECAST AREA TODAY AS A FRONTAL BOUNDARY STALLS OVER THE
FORECAST AREA. A FEW SHOWERS HAVE DEVELOPED THIS MORNING ALONG
THIS FRONTAL BOUNDARY AND THIS COULD SERVE AS A FOCUS FOR SOME
SHOWER DEVELOPMENT THROUGHOUT THE DAY AS TEMPERATURES ARE EXPECTED
TO CLIMB INTO THE LOWER 80S. WITH THIS BOUNDARY IN PLACE AND AMPLE
MOISTURE IN PLACE...A FEW SHOWERS AND MAYBE EVEN A THUNDERSTORM
COULD DEVELOP THIS AFTERNOON. SOME OF THE SHORT RANGE MODELS THE
HI-RES ARW AND NMM...AND EVEN THE HRRR SHOW ON AND OFF SHOWERS
THROUGHOUT THE DAY WITH MORE ACTIVITY IN THE AFTERNOON MAINLY
NORTH OF LAKE PONTCHARTRAIN. HAVE CARRIED ONLY SLIGHT CHANCE POPS
BUT WE COULD SEE AN UPDATE AT SOME POINT TODAY IF SHOWERS BECOME
MORE NUMEROUS. OVERALL IT SHOULD BE A RELATIVELY QUIET DAY AND
AGAIN FOR FRIDAY. 13/MH
.LONG TERM...
THE NEXT ORGANIZED CHANCE FOR RAIN LOOKS TO COME THIS WEEKEND
BEGINNING SATURDAY MORNING WITH THE BULK OF THE PRECIPITATION
OCCURRING SATURDAY NIGHT INTO SUNDAY MORNING. A FAIRLY STRONG
SOUTHERN STREAM UPPER LEVEL LOW WILL BEGIN TO PUSH INTO TEXAS FROM
NORTHERN MEXICO AND THIS ENERGY WILL MOVE OVER THE FORECAST AREA
OVER THE WEEKEND. THE PREVIOUS FORECAST LOOKS TO BE ON TRACK AS
THIS SYSTEM WILL BRING RAIN AND SOME THUNDERSTORMS TO THE REGION.
SOME OF THESE SHOWERS AND STORMS COULD BE DECENT RAIN PRODUCERS AS
DEEP MOISTURE AND THE DEPTH OF THE WARM CLOUD LAYERS SHOULD ALLOW
FOR PERIODS OF HEAVY RAIN SATURDAY AND SUNDAY. RIGHT NOW THIS DOES
NOT LOOK LIKE A SEVERE WEATHER SETUP FOR THE AREA. HAVE INCREASED
RAIN CHANCES FOR THE ENTIRE AREA AND HAVE PUSHED INTO THE
CATEGORICAL RANGE FOR AREAS ALONG AN NORTH OF LAKE PONTCHARTRAIN
FOR SATURDAY NIGHT. THE SYSTEM WILL PUSH THROUGH ON SUNDAY AND WE
WILL STILL HAVE SOME LINGERING SHOWERS ON SUNDAY. THE UPPER LOW
MOVES OFF TO THE EAST ON MONDAY AS WE DRY OUT AND HIGH PRESSURE
MOVES INTO THE AREA. TEMPERATURES WILL COOL BACK TO MORE NORMAL
READINGS IN THE LOWER 70S FOR MONDAY AND TUESDAY...AND OVERNIGHT
LOWS WILL BE NEAR AVERAGE IN THE 50S. A FAIRLY STRONG MID AND
UPPER LEVEL RIDGE WILL DOMINATE ON TUESDAY AND WEDNESDAY...AND THE
STRONG SUBSIDENCE ALOFT WILL KEEP CLEAR SKIES IN PLACE ACROSS THE
REGION 13/MH
&&
.AVIATION...
CURRENTLY MAJORITY OF THE TERMINALS ARE STILL
EXPERIENCING VFR CONDITIONS BUT THIS MAY CHANGE DURING THE EARLY
MORNING HRS. MVFR AND TEMPO IFR CIGS AND VSBYS COULD DEVELOP.
CONDITIONS SHOULD THEN RETURN TO VFR SHORTLY AFTER SUNRISE. /CAB/
&&
.MARINE...
OVER THE NEXT 4 DAYS LOOK FOR BENIGN CONDITIONS TO DOMINATE THE
COASTAL WATERS WITH VARIABLE WINDS OF 10 KNOTS OR LESS EXPECTED AS
A BROAD AREA OF HIGH PRESSURE REMAINS PARKED OVER THE NORTHERN
GULF OF MEXICO AND A WEAK STALLED BNDRY LIES JUST NORTH OF THE
COAST. SEAS WILL GENERALLY RANGE FROM 1 TO 3 FEET...AND DO NOT
EXPECT ANY SIGNIFICANT MARINE IMPACTS DURING THIS PERIOD. THINGS
SHOULD FINALLY CHANGE LATE SUNDAY AS A SFC LOW MOVES ACROSS THE
REGION AND DRAGS THE FRONT SOUTH LEADING TO MODERATE OFFSHORE
WINDS SUN NIGHT AND INTO NEXT WEEK. /CAB/
&&
.DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 78 61 80 63 / 30 20 40 40
BTR 81 62 82 64 / 30 20 30 40
ASD 80 63 81 65 / 30 20 30 30
MSY 80 63 80 65 / 20 20 20 20
GPT 77 63 77 64 / 30 20 30 20
PQL 80 62 79 64 / 30 20 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DULUTH MN
401 AM CDT THU MAR 19 2015
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 401 AM CDT THU MAR 19 2015
MAIN FORECAST CHALLENGES THIS MORNING ARE RAIN/SNOW CHANCES
THROUGH THIS AFTERNOON AND AGAIN ON FRIDAY AFTERNOON.
WARM AIR ADVECTION AND WEAK MID-LEVEL FRONTOGENESIS SUPPORTED A
BAND OF LIGHT SNOW FROM EASTERN NORTH DAKOTA SOUTHEAST TO WESTERN
WISCONSIN EARLY THIS MORNING. VERY DRY AIR IN THE MID/LOW- LEVELS
AS INDICATED BY 00Z MPX/INL SOUNDINGS AND MID-LEVEL CEILINGS WAS
EVAPORATING PRECIPITATION FROM CENTRAL MINNESOTA TO WESTERN
WISCONSIN. HAVE TRENDED FORECAST TOWARD NAM/SREF SOLUTION THROUGH
LATE AFTERNOON. EXPECT AREA FROM BRAINERD TO WALKER TO SATURATE
WITH A BRIEF PERIOD OF LIGHT SNOW BEFORE BAND MOVES OUT. SNOW
WILL CHANGE OVER TO RAIN BY NOON AS IT MOVES INTO FAR NORTH-
CENTRAL AND NORTHEAST MINNESOTA. EXPECT LESS THAN THREE-TENTHS OF
AN INCH OF SNOW ACCUMULATION... MAINLY ON GRASSY SURFACES.
TEMPERATURES WILL TREND SLIGHTLY WARMER WITH HIGHS IN THE UPPER
30S NORTHEAST AND THE LOW 50S SOUTHWEST.
PRECIPITATION WINDS DOWN TONIGHT IN NORTHEAST MINNESOTA. FORECAST
DRY FOR THE REMAINDER OF THE NIGHT AS WEAK SURFACE RIDGE SLIDES
THROUGH THE STATE. WITH WEAK WARM ADVECTION THROUGH TODAY...THINK
OVERNIGHT LOWS TONIGHT WILL TREND SLIGHTLY WARMER AS WELL. LOOK
FOR MIN TEMPS IN THE UPPER 20S NORTH TO THE LOW 30S SOUTH.
NEXT CLIPPER SYSTEM WILL MOVE INTO THE AREA ON FRIDAY BRINGING AN
INCREASE IN CLOUD COVER AND A BAND OF LIGHT RAIN...CHANGING OVER
TO SNOW ALONG THE NORTHERN EDGE DURING THE LATE AFTERNOON HOURS.
PREFER A CONSENSUS BLEND WEIGHTED TOWARD THE NAM/SREF FOR TIMING
AND POPS. RAIN TOTALS OF AROUND FIVE ONE-HUNDREDTHS SEEM
REASONABLE...WITH SOME SPOTS POSSIBLY RECEIVING A TENTH OF AN
INCH. TEMPS WILL TREND WARMER ACROSS THE SOUTH ONCE AGAIN WITH
STRONG WARM ADVECTION AHEAD OF THE CLIPPER. CLOUDS ACCOMPANYING
THE APPROACHING CLIPPER WILL LIMIT INSOLATION AND HEATING ACROSS
THE NORTH. HIGHS WILL REACH THE UPPER 30S NORTH...AND THE MIDDLE
50S SOUTHEAST.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 401 AM CDT THU MAR 19 2015
HIGH PRESSURE WILL MOVE INTO THE NORTHLAND AND UPPER MIDWEST OVER
THE WEEKEND AND HELP KEEP THE NORTHLAND DRY THROUGH EARLY NEXT
WEEK. TEMPERATURES WILL BE ABOUT 10 DEGREES BELOW NORMAL ON
SATURDAY...BUT WILL BUILD BACK TO NORMAL BY MONDAY.
THERE ARE SIGNS THAT A SIGNIFICANT STORM SYSTEM COULD DEVELOP IN
THE HIGH PLAINS AND MOVE THROUGH THE MINNESOTA AND WISCONSIN
DURING THE MIDDLE OF NEXT WEEK. THE GFS AND ECMWF ARE BOTH
INDICATING THIS SYSTEM. THE STORM IS TOO FAR OUT IN TIME TO
GATHER MUCH DETAILS...SO FORECASTED A MIXTURE OF RAIN AND SNOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1225 AM CDT WED MAR 18 2015
DRY AIR COVERED MUCH OF THE NORTHLAND LATE THIS EVENING AS SEEN
ON FORECAST SOUNDINGS AND EARLIER 00Z KMPX/KINL SOUNDINGS.
SURFACE DEWPOINTS HAVE BEEN INCREASING THOUGH. AREA RADARS
CONTINUE TO SHOW RETURNS FROM NORTHWEST NORTH DAKOTA SOUTHEAST
INTO WESTERN WISCONSIN. MUCH OF THESE RETURNS WERE NOT PRODUCING
PRECIP AT THE SURFACE...BUT THERE ARE SOME AREAS OF LIGHT SNOW OR
RAIN OCCURRING WEST OF THE NORTHLAND. WE DO NOT EXPECT MUCH
PRECIP ACROSS THE NORTHLAND TONIGHT...AS THE FGEN CONTINUES TO
WEAKEN. A SHORTWAVE OVER FAR WESTERN NORTH DAKOTA LATE THIS
EVENING WILL MOVE EAST ACROSS THE NORTHLAND ON THURSDAY. THERE
WILL BE A CHANCE FOR A LIGHT MIX ON THURSDAY WHICH SHOULD BECOME
MAINLY RAIN AS THE BOUNDARY LAYER WARMS. OVERALL...VFR CONDITIONS
WILL PREVAIL THROUGH THE PERIOD. THERE WILL BE 3 TO 4 HOUR PERIOD
WHERE MVFR CEILINGS WILL BE POSSIBLE. AT THIS TIME...WE CONFINED
THE MENTION TO KINL AND KHIB. THE RAP IS LESS BULLISH ON THESE
CEILINGS COMPARED TO THE NAM.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 49 33 49 17 / 10 10 60 30
INL 46 29 38 6 / 40 10 10 10
BRD 52 31 52 20 / 10 10 40 20
HYR 48 33 54 19 / 0 10 50 50
ASX 49 34 52 19 / 10 0 40 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...HUYCK
LONG TERM...GROCHOCINSKI
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1225 AM CDT THU MAR 19 2015
.UPDATE...
ISSUED AT 1225 AM CDT WED MAR 18 2015
UPDATED FOR THE NEW 06Z AVIATION DISCUSSION BELOW.
UPDATE ISSUED AT 933 PM CDT WED MAR 18 2015
FORECAST REMAINS ON TRACK AND FEW CHANGES WERE NEEDED IN THE SHORT
TERM. FGEN BAND OF MAINLY SNOW SOUTH AND WEST OF THE NORTHLNAD CONTINUED
TO MAKE VERY SLOW PROGRESS NORTH THIS EVENING. FORECAST SOUNDINGS
AND EVENING KMPX/KINL SOUNDINGS CONTINUE TO INDICATE SOME VERY DRY
AIR IN PLACE ACROSS THE NORTHLAND. THIS FGEN IS EXPECTED TO WEAKEN
OVERNIGHT SO WE EXPECT LITTLE IN THE WAY OF PRECIP. WE WILL
CONTINUE A SMALL MENTION OF SNOW OVER PORTIONS OF NORTHERN
MINNESOTA LATE. THE 00Z NAM IS IN GOOD AGREEMENT WITH OUR CURRENT
FORECAST. WE MADE SOME MINOR ADJUSTMENTS TO TEMPS TONIGHT TO
ACCOUNT FOR CURRENT TRENDS.
AN UPPER WAVE WILL MOVE IN THURSDAY MORNING BRINGING A CHANCE FOR
MORE LIGHT PRECIP. ANY PRECIP WOULD START AS A MIX OR MAINLY
SNOW...THEN SWITCH OVER TO LIGHT RAIN.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 412 PM CDT WED MAR 18 2015
WIDESPREAD CIRROSTRATUS WILL CONTINUE TO STREAM ACROSS THE DULUTH
CWA TONIGHT..AND WILL THICKEN WITH TIME FROM SOUTH TO NORTH IN
ADVANCE OF A WEAK SHORT WAVE APPROACHING FROM THE DAKOTAS. SURFACE
WINDS WILL BECOME LIGHT SOUTH TO SOUTHEAST TONIGHT AS SURFACE HIGH
PRESSURE MOVES OFF TO THE EAST. TEMPS TONIGHT WILL LIKELY NOT DROP
TOO FAR/FAST WITH THE INCREASINGLY THICK CLOUD COVER. HOWEVER..
TEMPS ACROSS FAR NORTHERN MINNESOTA AND ESPECIALLY THE INTERIOR
ARROWHEAD WHERE CLOUDS WILL BE THINNER AND WINDS NEAR CALM..MAY
DROP A BIT MORE THEN WE HAVE FORECASTED.
WEAK ASCENT WILL LIKELY RESULT IN SCATTERED RAIN AND SNOW SHOWERS
ON THURSDAY. PTYPE WILL BE DEPENDENT ON BOUNDARY LAYER TEMPS..WITH
SNOW SHOWERS MORE LIKELY IN THE MORNING AND AGAIN IN THE
EVENING..WITH A CHANGE OVER TO MOSTLY RAIN SHOWERS DURING THE DAY
AS TEMPS WARM INTO THE MID 30S TO LOWER 40S. VERY DRY AIR IN THE
LOWEST LEVELS MAY ALSO RESULT IN A LOT OF THE PRECIP EVAPORATING
BEFORE REACHING THE GROUND. BEST CHANCES FOR A COUPLE TENTHS OF AN
INCH OF SNOW WILL BE ACROSS FAR NORTHERN MINNESOTA WHERE DEEPER
SATURATION WILL PERSIST FOR A LONGER PERIOD OF TIME.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 412 PM CDT WED MAR 18 2015
A COLD FRONT AND ASSOCIATED UPPER TROUGH WILL BE MOVING EWD
THROUGH NRN MN AND NRN WI THURSDAY NIGHT AND FRIDAY MORNING...WITH
LIGHT RAIN AND/OR SNOW SPREADING THROUGH THE REGION. A BRIEF BREAK
IN THE PRECIP WILL BE SEEN LATE FRI MORNING/EARLY AFTERNOON BEFORE
A POST FRONTAL TROUGH DROPS IN FROM THE NORTH AND PHASES WITH AN
SECONDARY SFC WAVE AND EMBEDDED MID-LEVEL TROUGH FROM THE
NORTHWEST. THIS SYSTEM ON FRIDAY WILL PRODUCE ANOTHER ROUND OF
MAINLY RAIN DURING THE DAY ALONG AND SOUTH OF THE HIGHWAY 2
CORRIDOR...AND A RAIN/SNOW MIX TO THE NORTH. RAINFALL AMOUNTS WILL
BE GENERALLY LIGHT...LESS THAN A QUARTER OF AN INCH WITH TRACE
SNOWFALL POSSIBLE. HIGH PRESSURE BUILDS IN FROM THE NORTH FOR THE
WEEKEND WITH A SLIGHT SHIFT IN THE RIDGE AXIS TO THE EAST BY
MONDAY AS THE NEXT SYSTEM MOVES FROM THE NRN/CENTRAL PLAINS INTO
THE MID MS RIVER VALLEY AND BRUSHES THE NORTHLAND WITH LOW-END
POPS IN THE BRAINERD AREA. THE NEXT SIGNIFICANT SYSTEM MOVES ON
TUESDAY WITH RAIN AND SNOW POSSIBLE.
MILD TEMPERATURES EXPECTED FRIDAY WITH HIGHS IN THE 40S AND LOWER
50S. HOWEVER THE FIRST PUSH OF COLD AIR ARRIVES FRIDAY NIGHT WITH
TEMPERATURES FALLING INTO THE SINGLE DIGITS TO LOWER 20S. THE COLD
AIR PERSISTS ON SATURDAY WITH HIGHS ONLY REACHING INTO THE 20S AND
LOWER/MID 30S. A SLIGHT WARMING TREND BEGINS SUNDAY INTO EARLY NEXT
WEEK WITH HIGHS EVENTUALLY INTO THE 40S...AND LOWS IN THE 20S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1225 AM CDT WED MAR 18 2015
DRY AIR COVERED MUCH OF THE NORTHLAND LATE THIS EVENING AS SEEN
ON FORECAST SOUNDINGS AND EARLIER 00Z KMPX/KINL SOUNDINGS.
SURFACE DEWPOINTS HAVE BEEN INCREASING THOUGH. AREA RADARS
CONTINUE TO SHOW RETURNS FROM NORTHWEST NORTH DAKOTA SOUTHEAST
INTO WESTERN WISCONSIN. MUCH OF THESE RETURNS WERE NOT PRODUCING
PRECIP AT THE SURFACE...BUT THERE ARE SOME AREAS OF LIGHT SNOW OR
RAIN OCCURRING WEST OF THE NORTHLAND. WE DO NOT EXPECT MUCH
PRECIP ACROSS THE NORTHLAND TONIGHT...AS THE FGEN CONTINUES TO
WEAKEN. A SHORTWAVE OVER FAR WESTERN NORTH DAKOTA LATE THIS
EVENING WILL MOVE EAST ACROSS THE NORTHLAND ON THURSDAY. THERE
WILL BE A CHANCE FOR A LIGHT MIX ON THURSDAY WHICH SHOULD BECOME
MAINLY RAIN AS THE BOUNDARY LAYER WARMS. OVERALL...VFR CONDITIONS
WILL PREVAIL THROUGH THE PERIOD. THERE WILL BE 3 TO 4 HOUR PERIOD
WHERE MVFR CEILINGS WILL BE POSSIBLE. AT THIS TIME...WE CONFINED
THE MENTION TO KINL AND KHIB. THE RAP IS LESS BULLISH ON THESE
CEILINGS COMPARED TO THE NAM.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 26 45 33 48 / 10 20 30 50
INL 20 44 29 37 / 10 20 10 20
BRD 31 50 31 50 / 10 20 20 50
HYR 27 48 33 52 / 10 20 20 40
ASX 23 46 34 51 / 10 20 20 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...BJT
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1148 PM MDT WED MAR 18 2015
.AVIATION...
06Z TAF CYCLE
THE CURRENT BATCH OF SHOWERS OVER THE NORTHERN HIGH TERRAIN AND
THE NORTHEAST PLAINS WILL EXIT SLOWLY THROUGH SUNRISE. CLEARING
BEHIND THIS WAVE MAY ALLOW FOR FOG DEVELOPMENT AROUND THE AREAS
MENTIONED EARLIER TONIGHT...FROM KAEG TO KABQ/KSAF AND KLVS.
WIDESPREAD RAINFALL BTWN 0.05 AND 0.15 WAS REPORTED AND CURRENT
DEWPOINT DEPRESSIONS ARE ON THE ORDER OF 3 SO IT LOOKS MORE
POSSIBLE WITH THIS AREA OF CLEARING. PLACED TEMPO GROUPS FOR
JUST A COUPLE HOURS TO NARROW IN ON BEST WINDOW...BEFORE THE
NEXT AREA OF CLOUD COVER INCREASING OVERHEAD FROM THE SOUTHWEST.
THURSDAY STILL LOOKS LIKE A VERY DYNAMIC DAY AFT 18Z AS A COLD
FRONT MOVES INTO THE AREA BENEATH AN APPROACHING UPPER WAVE.
WIDESPREAD SHOWERS AND THUNDERSTORMS...RAIN CHANGING TO SNOW IN
THE HIGH TERRAIN...AND GUSTY WINDS ARE EXPECTED BEHIND THE FRONT.
GUYER
&&
.PREV DISCUSSION...822 PM MDT WED MAR 18 2015...
.UPDATE...
A BACK DOOR COLD FRONT SHOULD LOWER SNOW LEVELS ACROSS THE
NORTHERN MOUNTAINS LATE THURSDAY...SO WE DECIDED TO ISSUE A WINTER
STORM WATCH. SEVERAL INCHES TO LOCALLY NEAR 1 FOOT OF SNOW WILL BE
POSSIBLE. ALSO ADDED FOG TO THE FORECAST FOR THE MORENO VALLEY
LATE TONIGHT DUE TO ALL THE MOISTURE THAT WILL SOCK IN THAT AREA.
CONSIDERED FORECASTING FOG FOR OTHER LOCATIONS...BUT SKY COVER
SHOULD STAY THICK ENOUGH TO PREVENT MUCH DEVELOPMENT.
44
&&
.PREV DISCUSSION...328 PM MDT WED MAR 18 2015...
.SYNOPSIS...
AN UPPER LOW NEAR SAN DIEGO WILL COMBINE WITH PLENTY OF LOW LEVEL MOISTURE
TO BRING SCATTERED TO NUMEROUS SHOWERS TO MUCH OF CENTRAL AND
NORTHERN NEW MEXICO TONIGHT. THIS SAME UPPER LOW WILL COMBINE
WITH ANOTHER UPPER LEVEL STORM SYSTEM DROPPING IN FROM THE
NORTHWEST ALONG WITH A BACKDOOR COLD FRONT TO PRODUCE NUMEROUS
SHOWERS TO THE NORTHERN TWO THIRDS OF NEW MEXICO THURSDAY AND
THURSDAY NIGHT. BRIEF HEAVY RAIN AND SMALL HAIL IS LIKELY WITH THE
STRONGER SHOWERS AND THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.
PLENTIFUL RESIDUAL MOISTURE WILL KEEP SCATTERED SHOWERS IN THE
FORECAST FRIDAY...WITH A DRYING AND WARMING TREND EXPECTED FOR THE
WEEKEND.
&&
.DISCUSSION...
BAND OF LIGHT TO MODERATE RAIN EXTENDS FROM CATRON AND WESTERN
SOCORRO COUNTIES NORTHWARD INTO EASTERN CIBOLA AND SOUTHEAST
MCKINLEY COUNTIES WILL CONTINUE TO SLOWLY MOVE EASTWARD THIS EVENING.
BIG QUESTION IS WHETHER OR NOT THIS BAND WILL MAKE THE TRIP DOWNWARD
INTO THE RIO GRANDE VALLEY. 18Z NAM12 AND 18Z HRRR MODELS
INDICATING THAT THIS LINE...IN FACT...WILL MAKE IT INTO THE RGV AND
GIVEN THE CURRENT TEMP OF 66F AT THE ABQ SUNPORT AND THE 40F
DEWPOINT TEMPERATURE...SUSPECT THAT THESE HIGH RESOLUTION MODELS
ARE ON TO SOMETHING. WAVE/SPEED MAX MOVING UP FROM THE SOUTH WILL
SHIFT MAIN FOCUS FOR SHOWERS LATE TONIGHT TO THE SOUTHWEST
MOUNTAINS. ADDITIONALLY...SHOWERS WILL ALSO FOCUS OVER THE
NORTHEAST PLAINS LATE TONIGHT AND THURSDAY MORNING AS A BACKDOOR
FRONT DROPS IN. NORTHERN STREAM SHORT- WAVE TROUGH STILL PROGGED
TO PHASE WITH THE SOUTHERN STREAM CLOSED LOW OVER ERN AZ/WRN NM THURSDAY.
GOOD LAPSE RATES/INSTABILITY...ASSOCIATED LIFT FROM 100KT SUBTROPICAL
JET OVER SE NM AND COPIOUS AMOUNTS OF PACIFIC MOISTURE WILL
COMBINE WITH A BACKDOOR COLD FRONT TO GENERATE NUMEROUS SHOWERS
AND THUNDERSTORMS THURSDAY AND THURSDAY NIGHT.
UPPER LOW TO THE SOUTHWEST REMAINS IN TACT AND PASSES EASTWARD WELL
SOUTH OF NM WHILE THE NRN STREAM TROUGH SHEARS APART AND FILLS
OVER THE STATE FRIDAY AND FRIDAY NIGHT. PLENTY OF RESIDUAL
MOISTURE WILL COMBINE WITH DECENT LAPSE RATES/INSTABILITY AND
DAYTIME HEATING TO PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS
OVER THE WESTERN AND NORTHERN MOUNTAINS FRIDAY AFTERNOON AND
EVENING.
ON SATURDAY...WEST COAST RIDGE CONTINUES TO PROPAGATE EAST AND FOLD
OVER AND THE RESULTING HIGHER HEIGHTS AND A VERY DRY NORTHERLY
FLOW ALOFT LIMIT SHOWERS CHANCES SATURDAY AND ALL BUT ELIMINATE
CHANCES SUNDAY INTO EARLY NEXT WEEK. MODELS AGREE THAT A DRY ZONAL
FLOW SETS UP OVER THE SOUTHWEST U.S. EARLY NEXT WEEK WITH THE
POTENTIAL FOR A TROUGH DROPPING SEWD INTO THROUGH COLORADO AND
CLIPPING THE NE AROUND MIDWEEK. 33
&&
.FIRE WEATHER...
WELL ABOVE NORMAL PWATS OVER THE AREA TO PERSIST THROUGH FRIDAY WITH
A GRADUAL DRYING TREND TAKING PWATS DOWN TO NEAR NORMAL VALUES FOR
MARCH BY THE END OF THE WEEKEND. FURTHER DRYING FORECAST EARLY NEXT
WEEK WITH THE POTENTIAL FOR CRITICAL FIRE WEATHER CONDITIONS AS
EARLY AS TUESDAY.
CHANCES FOR WETTING PRECIPITATION WILL BE ON THE INCREASE THROUGH
THURSDAY NIGHT AS A SLOW MOVING TROUGH APPROACHES FROM THE WEST AND
A BACKDOOR COLD FRONT MAKES SOUTHWEST PROGRESS. THE 12Z MODEL
SOLUTIONS AND RESULTING MOS ARE WETTER THAN THE PAST SEVERAL RUNS
FOR CENTRAL AND NORTHERN NEW MEXICO LATE THURSDAY THROUGH THURSDAY
NIGHT DUE TO THE TIMING OF THE BACKDOOR FRONT COINCIDING WITH THE
NORTHERN STREAM TROUGH DROPPING INTO THE AREA AND PHASING WITH THE
SLOW MOVING SOUTHERN STREAM TROUGH. NOT MUCH IN THE WAY OF LIGHTNING
ACTIVITY LATE THIS AFTERNOON THROUGH TONIGHT...BUT AN UPTICK IS
EXPECTED THURSDAY AND FRIDAY.
A DRYING/WARMING TREND TO KICK-OFF SATURDAY WITH TEMPERATURES
RETURNING TO ABOVE NORMAL. A LAST ROUND OF DAYTIME HEATING TRIGGERED
CONVECTION IS FORECAST SATURDAY...ALTHOUGH COVERAGE OF WETTING
PRECIPITATION WILL BE VERY LOW. VENT RATES ARE FORECAST TO IMPROVE
THROUGH THE WEEKEND WITH THE WARMING AND INCREASING WIND PROFILE.
EARLY NEXT WEEK WILL FEATURE INCREASING WESTERLY FLOW...CONTINUED
DRYING WITH INCREASING HAINES...MIXING AND VENT RATES. POTENTIAL FOR
CRITICAL FIRE WEATHER CONDITIONS ON THE UPTREND TUESDAY AND MAY
EXTEND INTO WEDNESDAY PRIOR TO A COLD FRONT...ALTHOUGH THE PRECEDING
LEE SIDE TROUGH DOES NOT LOOK PARTICULARLY DEEP AT 1001MB. MODERATE
FORECASTER CONFIDENCE ON THE MON/TUE FORECAST AT THIS TIME GIVEN
GOOD AGREEMENT BETWEEN THE 12Z GFS AND ECMWF SOLUTIONS. 11
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY MORNING
FOR THE FOLLOWING ZONES...NMZ510>515.
&&
$$
AREA FORECAST DISCUSSION
NWS BISMARCK ND
100 AM CDT THU MAR 19 2015
.UPDATE...
ISSUED AT 100 AM CDT THU MAR 19 2015
MAIN CHANGE THIS UPDATE WAS TO KEEP CURRENT ON RADAR TRENDS AND
LATEST SHORT TERM HIGH RES MODELS FOR EXPECTED MOVEMENT OF AREA OF
LIGHT SNOW.
UPPER LEVEL SHORTWAVE LOW/TROUGH WAS OVER NORTHEASTERN
MONTANA/NORTHWESTERN NORTH DAKOTA. AT THE SURFACE...A LOW PRESSURE
TROUGH EXTENDED FROM WESTERN NEBRASKA TO SOUTHWESTERN NORTH DAKOTA
AND INTO EASTERN MONTANA. LOW LEVEL FLOW WAS SOUTHEASTERLY ACROSS
EASTERN SOUTH DAKOTA AND NORTH DAKOTA...WITH A STRONG H850 SOUTHERLY
WIND. LOW LEVEL LIFT EXTENDED IN AN ARC FROM THE UPPER LEVEL LOW TO
MINOT...HARVEY...JAMESTOWN/FARGO. THIS ARC IS EXPECTED TO PIVOT
NORTH...THEN WRAP AROUND THE UPPER LOW AS THE UPPER LOW MOVES
EAST/SOUTHEAST ACROSS THE STATE THIS MORNING...REACHING MINNESOTA
AROUND NOON. THE AREA OF LIGHT SNOW AND LOW CLOUDS SHOULD BE ACROSS
NORTHERN NORTH DAKOTA EARLY THIS MORNING...THEN PIVOT AROUND AND
BEGIN MOVING INTO DICKINSON AND BISMARCK BEFORE DAYBREAK...FINALLY
REACHING JAMESTOWN. HOWEVER...PRECIPITATION CHANCES SHOULD DECREASE
DURING THE MORNING AS THE UPPER LEVEL LOW/TROUGH EXITS THE AREA.
UPDATE ISSUED AT 853 PM CDT WED MAR 18 2015
PERSISTENT LIGHT SNOW WILL REQUIRE A LARGER AND LONGER PERIOD OF
SNOW ACROSS THE NORTH CENTRAL INTO THE JAMES RIVER VALLEY. DID
THAT WITH THIS UPDATE. VISIBILITIES IN THE SNOW SEEM TO CONFIRM
ITS FAIRLY LIGHT...WITH VSBYS GENERALLY A MILE OR ABOVE...ALSO
CONFIRMED BY DOT CAMERAS...AND SURFACE TEMPERATURES ARE 33 TO 36
MOST AREAS SO THERE IS SOME MELTING. NDOT TRAVEL MAP SHOWS WET AND
SLUSHY AREAS ACROSS THE AREA OF RADAR COVERAGE. SO A BOOST TO THE
POPS IS THE MAIN CHANGE FOR THE EVENING.
UPDATE ISSUED AT 636 PM CDT WED MAR 18 2015
RADAR AND SURFACE REPORTS SHOW A BAND OF MOSTLY SNOW ACROSS NORTH
CENTRAL NORTH DAKOTA. GLASGOW RADAR NOW SHOWING THE SNOW WILL TAPER
OFF AT WILLISTON. WILL INCORPORATE THESE TRENDS IN THE UPDATED
FORECAST AND GO CATEGORICAL SNOW NORTH THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 342 PM CDT WED MAR 18 2015
HIGHLIGHTS OF THE SHORT TERM ARE SNOWFALL AND FOG THROUGH TONIGHT.
AS OF 20 UTC...A BAND OF LIGHT TO MODERATE SNOW WAS CENTERED ALONG
A LINE FROM WATFORD CITY THROUGH JAMESTOWN. THIS BAND IS EXPECTED
TO CONTINUE TO PROPAGATE NORTHEAST THROUGH THE EVENING AND SLOWLY
WEAKEN...BECOMING CENTERED ALONG THE US HIGHWAY 2 CORRIDOR AS
DEPICTED BY THE 17-19 UTC HRRR AND 18 UTC NAM SOLUTIONS.
ADDITIONAL ACCUMULATIONS OF LESS THAN ONE INCH ARE EXPECTED GIVEN
THE VERY LOW SNOW RATIOS THAT HAVE BEEN OBSERVED THROUGH THE DAY.
DID ADD A MENTION OF FOG ACROSS THE WEST TONIGHT WITH STRATUS
BUILD DOWN AS WINDS BECOME LIGHT IN THE INVERTED TROUGH AXIS.
SCATTERED RAIN AND SNOW SHOWERS MAY LINGER INTO THURSDAY MORNING
IN ASSOCIATION WITH THE DEPARTING UPPER LEVEL WAVE...WITH MOSTLY
SUNNY CONDITIONS EXPECTED BY AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM CDT WED MAR 18 2015
AN ACTIVE LONG TERM PERIOD. THE HUDSON BAY LOW SHIFTS EAST THROUGH
THE PERIOD ALLOWING FOR A MORE ENERGETIC/MOIST PACIFIC FLOW WITH
SEVERAL SHORTWAVES TO MOVE ACROSS NORTH DAKOTA. ONE LAST SHORTWAVE
ASSOCIATED WITH THE HUDSON BAY LOW WILL PUSH A CLIPPER SYSTEM ACROSS
MAINLY NORTH CENTRAL INTO EAST CENTRAL NORTH DAKOTA FRIDAY. HAVE
INCREASED POPS TO LIKELY CATEGORY IN THE NORTH CENTRAL/TURTLE
MOUNTAINS WITH ALL MODELS DEPICTING THE SHORTWAVE AND ASSOCIATED
PRECIPITATION ACROSS THIS AREA. COULD BE AROUND ONE INCH IN THE
TURTLE MOUNTAINS. POPS TAPER OFF TO BELOW MEASURABLE FARTHER SOUTH
AND WEST. AS THE FLOW TRANSITIONS FROM NORTHWEST TO ZONAL FLOW...A
SERIES OF SHORTWAVES SHIFTING EAST FROM THE PACIFIC QUICKLY MOVE
TOWARD NORTH DAKOTA. A WEAK SHORTWAVE SLIDES THROUGH SATURDAY WITH A
CHANCE OF SNOW/RAIN MOSTLY AFFECTING NORTHWEST THROUGH NORTH CENTRAL
NORTH DAKOTA. THEREAFTER...TWO SIGNIFICANT MID LEVEL SHORTWAVES WILL
NEED MONITORING. THE FIRST SHORTWAVE COMES THROUGH WESTERN AND
CENTRAL NORTH DAKOTA...NEGATIVELY TILTED...SUNDAY INTO SUNDAY NIGHT.
THIS WILL PRODUCE WIDESPREAD SNOW ACROSS CENTRAL NORTH DAKOTA WITH
THE GFS AND ECMWF DEPICTING TWO TO THREE TENTHS OF LIQUID...OR
POSSIBLY 2 TO 3.5 INCHES OF SNOW FOR PORTIONS OF CENTRAL NORTH
DAKOTA. TEMPERATURES SHOULD BE WARMER SOUTHWEST FOR SNOW CHANGING
OVER TO RAIN IN THE AFTERNOON. A BRIEF TRANSITORY RIDGE SLIDES BY
MONDAY/MONDAY NIGHT BEFORE THE NEXT POTENT SHORTWAVE ARRIVES
TUESDAY/WEDNESDAY. THE GFS IS FARTHER SOUTH WITH THE LOW PRESSURE
COMPLEX...SLIDING THROUGH CENTRAL/NORTHERN SOUTH DAKOTA RESULTING IN
COLDER AIR TO BE DRAWN INTO THE LOW WITH WIDESPREAD SNOW FOR
CENTRAL/SOUTHERN NORTH DAKOTA. THE ECMWF IS FARTHER NORTH WITH THIS
SYSTEM AND PRODUCES SOME LIGHT PRECIPITATION IN THE WARM AIR
ADVECTION TUESDAY FOLLOWED BY A DRY SLOT. SOME SNOW SHOWERS DEVELOP
ON THE BACK SIDE OF THE LOW WITH COLD AIR ADVECTION COMMENCING
TUESDAY NIGHT INTO WEDNESDAY. OVERALL THE ECMWF IS WEAKER WITH
REGARDS TO QPF THAN THE GFS. WILL ALSO NEED TO MONITOR THIS IN THE
COMING DAYS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 100 AM CDT THU MAR 19 2015
TROUGH OF LOW PRESSURE CONTINUED LIFTING NORTH ACROSS NORTHERN NORTH
DAKOTA THIS MORNING. AS THE SYSTEM PIVOTS AND BEGINS MOVING
SOUTHEAST DURING THE NIGHTTIME HOURS MVFR/IFR CONDITIONS WILL
RETURN TO TAF SITES. LIGHT SNOW AND FOG WILL REDUCE VSBYS AND
CEILINGS TO IFR CONDITIONS ACROSS KISN AND KMOT UNTIL AROUND 18Z.
KDIK- KBIS-KJMS WILL GENERALLY SEE VFR AT 06Z UNTIL MVFR AND IFR
CIGS MOVE INTO KDIK AROUND 08Z...KBIS 09Z-11Z...AND REACHING KJMS
AROUND 16Z. VFR CONDITIONS EXPECTED TO DEVELOP FROM NORTHWEST TO
SOUTHEAST...BEGINNING AT 18Z NORTHWEST AND FINALLY EXITING KJMS BY
AROUND 00Z.
&&
.HYDROLOGY...
ISSUED AT 342 PM CDT WED MAR 18 2015
THE WILLOW CREEK NEAR WILLOW CITY IS FORECAST TO CONTINUE TO RISE
INTO THURSDAY...CRESTING JUST BELOW FLOOD STAGE. HOWEVER...PRECIPITATION
THIS WEEKEND INTO NEXT WEEK MAY LEAD TO ADDITIONAL RISES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JV
SHORT TERM...AYD
LONG TERM...KS
AVIATION...JV
HYDROLOGY...AYD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
208 AM EDT THU MAR 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL BUILD EAST INTO
PENNSYLVANIA TODAY. AN AREA OF LOW PRESSURE WILL TRACK SOUTH OF
PENNSYLVANIA FRIDAY...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT SATURDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
MCLEAR SKIES AND A DIMINISHING WIND ASSOC WITH ARRIVAL OF SFC HIGH
WILL ALLOW TEMPS TO FALL STEADILY THRU SUNRISE. LATE AFTN DWPTS
AND LATEST RAP OUTPUT SUGGEST SOME OF THE NORMALLY COLDER VALLEYS
ACROSS THE NW COUNTIES COULD DIP INTO THE SINGLE DIGITS.
HOWEVER...A BLEND OF LATEST LAMP AND RAP SUGGEST AVERAGE READINGS
BY DAWN WILL RANGE FROM THE LTEENS ACROSS THE N MTNS...TO THE M20S
IN THE SOUTHERN VALLEYS. IR LOOP SUGGESTS THE SW COUNTIES WILL BE
ON THE EDGE OF CIRRUS SHIELD EARLY THIS MORNING...WHILE CLEAR
SKIES PREVAIL ELSEWHERE.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM FRIDAY/...
SFC HIGH WILL PASS OVER THE STATE TODAY...MAINTAINING FAIR AND COOL
WEATHER WITH LGT WIND. UPSTREAM SATL IMAGERY AND 00Z MDL 500-300MB
RH FIELDS SUGGEST CIRRUS WILL DIM THE SUN ACROSS SOUTHERN
PA...WHILE BRIGHT SKIES PREVAIL FURTHER NORTH. ENS MEAN 925/850MB
TEMPS SHOULD SUPPORT MAX TEMPS FROM THE MID 30S OVR THE N MTNS TO
THE 40S ELSEWHERE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
CONTINUED INCREASE FOR CONFIDENCE FOR SNOW FRIDAY. ESPECIALLY
SINCE ALL MODEL GUIDANCE TRACKS FAST-MOVING SHORTWAVE THRU THE
AREA. THE SFC LOW DOES REMAIN WEAK AS IT TRACKS SOUTH OF THE
MASON DIXON LINE...COMBINATION OF WEAK SFC LOW AND HIGH OFF THE
NEW ENG COAST SHOULD CREATE ENOUGH SOUTHERLY FLOW/OVERRUNNING FOR
A LIGHT TO MOD PRECIP EVENT...ESPECIALLY IN THE PRE DAWN HOURS
OVER THE LAURELS. THE BIGGEST CAVEAT TO SNOWFALL THROUGH THE
LAURELS DURING THIS TIMEFRAME IS TEMPS ALOFT. HOWEVER CONSIDERING
THE OVERRUNNING AND THAT IT WILL WET BULB TO THE DEWPOINT...EXPECT
THAT...WHILE A MORE SATURATED SNOW...IT WILL BE AN INCREASE IN
AMOUNT.
THE LATEST HPC GUIDANCE HAS THE EPICENTER ALONG THE
LAURELS...HOWEVER GIVE THE SPEED OF THE SYSTEM...AND THAT THE SNOW
SNOW SHOULD END QUICKLY ONCE THE UPPER LEVEL TROUGH SWINGS THROUGH
AROUND 00Z SATURDAY. THE 12Z OPERATIONAL EC/GEFS/GFS HAS INCREASED
QPF FROM 00Z FRIDAY TO 00Z SATURDAY. SO CONFIDENCE IS HIGHER FOR
LARGER AMOUNTS. HOWEVER I DID TEMPER THEM CONSIDERING THE POSSIBLE
WET GROUND DUE TO RAIN STILL POSSIBLE EARLY IN THE EVENT...HIGHER
DAYTIME TEMPERATURES AND WET SNOW. HOWEVER GIVEN THE INCREASED
QPF...THE NATURE OF MILLER TYPE B EVENTS AND OVERALL STRENGTH OF
THE SYSTEM...HAVE INCREASED SNOWFALL AMOUNTS. THE CONSALL QPF AND
ASSUMPTION OF SNOW/WATER RATIOS SLIGHTLY LOWER THAN 10/1 TRANSLATE
TO LIKELY SNOW TOTALS OF 2-4 INCHES ACROSS A LARGE PORTION OF
CENTRAL PA...WITH A SWATH OF 4 TO 6 INCHES THROUGH A PORTION OF
SOUTHERN CENTRAL PA. GIVEN THE TIME OF YEAR AND MARGINAL SFC
TEMPS...MUCH OF THE ACCUM WOULD LIKELY BE ON NON- PAVEMENT
SURFACES. AS IS TYPICAL THIS TIME OF YEAR...DAYTIME SNOW ACCUMS
WILL LIKELY BE ELEVATION DEPENDENT...WITH THE HIGHEST AMTS ON THE
RIDGETOPS.
A FAIR AMT OF AGREEMENT THRU NEXT WEEKEND AMONG MED RANGE
GUIDANCE...ALL OF WHICH INDICATE A DEEP TROUGH FORMING OVR THE
NORTHEAST CONUS IN RESPONSE TO BUILDING RIDGE ON THE PACIFIC
COAST. 12Z GFS/CANADIAN/ECMWF ALL INDICATE PASSAGE OF A SHARP
COLD FRONT ON SATURDAY...FOLLOWED BY WELL BLW NORMAL TEMPS
SUNDAY/MONDAY.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
HIGH PRESSURE OVER THE GREAT LAKES WILL MIGRATE SEWD OVER CENTRAL
PA AIRSPACE TODAY BEFORE WEDGING EAST OF THE APPALACHIANS TONIGHT
INTO EARLY FRIDAY. THIS WILL ENSURE PREVAILING VFR CONDITIONS
THROUGH 3/4 OF THE PERIOD OR 00Z FRIDAY. SFC WINDS 290-330 DEC AOB
5KTS THROUGH THE AFTN THEN SHIFTING TO 090-150 FROM THIS EVENING
INTO TONIGHT. MOISTURE ASSOCIATED WITH A WEAK LOW PRESSURE SYSTEM
TRACKING INTO THE SRN MID-ATLC REGION WILL OVERRUN THE ESTABLISHED
COLD SECTOR AND RESULT IN WIDESPREAD MVFR TO IFR SNOW SPREADING SW
TO NE FROM APPROX 06-18Z FRI. TIMING MAY BE EARLIER IN THE SW AND
END A LITTLE LATER IN THE EAST. A RAIN/SNOW MIX IS STILL POSSIBLE
DURING THE AFTN OVER THE SE AIRFIELDS...BUT OVERALL THERMAL
PROFILES SUPPORT THE BULK OF THE PCPN AS SNOW. SNOW ENDS FROM W TO
EAST BY LATE FRI EVENING WITH LOW CIGS LKLY HOLDING INTO FRIDAY
NIGHT ESPECIALLY OVER THE WRN TAFS IN ZOB SECTOR. SOME LINGERING
DZ/FZDZ IS ALSO POSSIBLE INTO SATURDAY MORNING.
OUTLOOK...
SAT...MVFR/IFR -SHSN WEST...VFR CNTRL AND EAST. 20-25KT WIND GUSTS
FROM 270-300.
SUN-MON...NO SIG WX.
&&
.CLIMATE...
SPRING OFFICIALLY BEGINS AT 645 PM EDT ON MARCH 20 2015.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...FITZGERALD/CERU
AVIATION...STEINBUGL
CLIMATE...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
202 AM EDT THU MAR 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL BUILD EAST INTO
PENNSYLVANIA TODAY. AN AREA OF LOW PRESSURE WILL TRACK SOUTH OF
PENNSYLVANIA FRIDAY...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT SATURDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
MCLEAR SKIES AND A DIMINISHING WIND ASSOC WITH ARRIVAL OF SFC HIGH
WILL ALLOW TEMPS TO FALL STEADILY THRU SUNRISE. LATE AFTN DWPTS
AND LATEST RAP OUTPUT SUGGEST SOME OF THE NORMALLY COLDER VALLEYS
ACROSS THE NW COUNTIES COULD DIP INTO THE SINGLE DIGITS.
HOWEVER...A BLEND OF LATEST LAMP AND RAP SUGGEST AVERAGE READINGS
BY DAWN WILL RANGE FROM THE LTEENS ACROSS THE N MTNS...TO THE M20S
IN THE SOUTHERN VALLEYS. IR LOOP SUGGESTS THE SW COUNTIES WILL BE
ON THE EDGE OF CIRRUS SHIELD EARLY THIS MORNING...WHILE CLEAR
SKIES PREVAIL ELSEWHERE.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM FRIDAY/...
SFC HIGH WILL PASS OVER THE STATE TODAY...MAINTAINING FAIR AND COOL
WEATHER WITH LGT WIND. UPSTREAM SATL IMAGERY AND 00Z MDL 500-300MB
RH FIELDS SUGGEST CIRRUS WILL DIM THE SUN ACROSS SOUTHERN
PA...WHILE BRIGHT SKIES PREVAIL FURTHER NORTH. ENS MEAN 925/850MB
TEMPS SHOULD SUPPORT MAX TEMPS FROM THE MID 30S OVR THE N MTNS TO
THE 40S ELSEWHERE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
CONTINUED INCREASE FOR CONFIDENCE FOR SNOW FRIDAY. ESPECIALLY
SINCE ALL MODEL GUIDANCE TRACKS FAST-MOVING SHORTWAVE THRU THE
AREA. THE SFC LOW DOES REMAIN WEAK AS IT TRACKS SOUTH OF THE
MASON DIXON LINE...COMBINATION OF WEAK SFC LOW AND HIGH OFF THE
NEW ENG COAST SHOULD CREATE ENOUGH SOUTHERLY FLOW/OVERRUNNING FOR
A LIGHT TO MOD PRECIP EVENT...ESPECIALLY IN THE PRE DAWN HOURS
OVER THE LAURELS. THE BIGGEST CAVEAT TO SNOWFALL THROUGH THE
LAURELS DURING THIS TIMEFRAME IS TEMPS ALOFT. HOWEVER CONSIDERING
THE OVERRUNNING AND THAT IT WILL WET BULB TO THE DEWPOINT...EXPECT
THAT...WHILE A MORE SATURATED SNOW...IT WILL BE AN INCREASE IN
AMOUNT.
THE LATEST HPC GUIDANCE HAS THE EPICENTER ALONG THE
LAURELS...HOWEVER GIVE THE SPEED OF THE SYSTEM...AND THAT THE SNOW
SNOW SHOULD END QUICKLY ONCE THE UPPER LEVEL TROUGH SWINGS THROUGH
AROUND 00Z SATURDAY. THE 12Z OPERATIONAL EC/GEFS/GFS HAS INCREASED
QPF FROM 00Z FRIDAY TO 00Z SATURDAY. SO CONFIDENCE IS HIGHER FOR
LARGER AMOUNTS. HOWEVER I DID TEMPER THEM CONSIDERING THE POSSIBLE
WET GROUND DUE TO RAIN STILL POSSIBLE EARLY IN THE EVENT...HIGHER
DAYTIME TEMPERATURES AND WET SNOW. HOWEVER GIVEN THE INCREASED
QPF...THE NATURE OF MILLER TYPE B EVENTS AND OVERALL STRENGTH OF
THE SYSTEM...HAVE INCREASED SNOWFALL AMOUNTS. THE CONSALL QPF AND
ASSUMPTION OF SNOW/WATER RATIOS SLIGHTLY LOWER THAN 10/1 TRANSLATE
TO LIKELY SNOW TOTALS OF 2-4 INCHES ACROSS A LARGE PORTION OF
CENTRAL PA...WITH A SWATH OF 4 TO 6 INCHES THROUGH A PORTION OF
SOUTHERN CENTRAL PA. GIVEN THE TIME OF YEAR AND MARGINAL SFC
TEMPS...MUCH OF THE ACCUM WOULD LIKELY BE ON NON- PAVEMENT
SURFACES. AS IS TYPICAL THIS TIME OF YEAR...DAYTIME SNOW ACCUMS
WILL LIKELY BE ELEVATION DEPENDENT...WITH THE HIGHEST AMTS ON THE
RIDGETOPS.
A FAIR AMT OF AGREEMENT THRU NEXT WEEKEND AMONG MED RANGE
GUIDANCE...ALL OF WHICH INDICATE A DEEP TROUGH FORMING OVR THE
NORTHEAST CONUS IN RESPONSE TO BUILDING RIDGE ON THE PACIFIC
COAST. 12Z GFS/CANADIAN/ECMWF ALL INDICATE PASSAGE OF A SHARP
COLD FRONT ON SATURDAY...FOLLOWED BY WELL BLW NORMAL TEMPS
SUNDAY/MONDAY.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
HIGH PRESSURE OVER THE GREAT LAKES WILL MIGRATE SEWD OVER CENTRAL
PA AIRSPACE TODAY BEFORE WEDGING EAST OF THE APPALACHIANS TONIGHT
INTO EARLY FRIDAY. THIS WILL ENSURE PREVAILING VFR CONDITIONS
THROUGH 3/4 OF THE PERIOD OR 00Z FRIDAY. SFC WINDS 290-330 DEC AOB
5KTS THROUGH THE AFTN THEN SHIFTING TO 090-150 FROM THIS EVENING
INTO TONIGHT. MOISTURE ASSOCIATED WITH A WEAK LOW PRESSURE SYSTEM
TRACKING INTO THE SRN MID-ATLC REGION WILL OVERRUN THE ESTABLISHED
COLD SECTOR AND RESULT IN WIDESPREAD MVFR TO IFR SNOW SPREADING SW
TO NE FROM APPROX 06-18Z FRI. TIMING MAY BE EARLIER IN THE SW AND
END A LITTLE LATER IN THE EAST. A RAIN/SNOW MIX IS STILL POSSIBLE
DURING THE AFTN OVER THE SE AIRFIELDS...BUT OVERALL THERMAL
PROFILES SUPPORT THE BULK OF THE PCPN AS SNOW. SNOW ENDS FROM W TO
EAST BY LATE FRI EVENING WITH LOW CIGS LKLY HOLDING INTO FRIDAY
NIGHT ESPECIALLY OVER THE WRN TAFS IN ZOB SECTOR. SOME LINGERING
DZ/FZDZ IS ALSO POSSIBLE INTO SATURDAY MORNING.
OUTLOOK...
SAT...MVFR/IFR -SHSN WEST...VFR CNTRL AND EAST. 20-25KT WIND GUSTS
FROM 270-300.
SUN-MON...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...FITZGERALD/CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1233 AM EDT THU MAR 19 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE GREAT LAKES WILL BUILD EAST INTO
PENNSYLVANIA TODAY. AN AREA OF LOW PRESSURE WILL TRACK SOUTH OF
PENNSYLVANIA FRIDAY...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT SATURDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
MCLEAR SKIES AND A DIMINISHING WIND ASSOC WITH ARRIVAL OF SFC HIGH
WILL ALLOW TEMPS TO FALL STEADILY THRU SUNRISE. LATE AFTN DWPTS
AND LATEST RAP OUTPUT SUGGEST SOME OF THE NORMALLY COLDER VALLEYS
ACROSS THE NW COUNTIES COULD DIP INTO THE SINGLE DIGITS.
HOWEVER...A BLEND OF LATEST LAMP AND RAP SUGGEST AVERAGE READINGS
BY DAWN WILL RANGE FROM THE LTEENS ACROSS THE N MTNS...TO THE M20S
IN THE SOUTHERN VALLEYS. IR LOOP SUGGESTS THE SW COUNTIES WILL BE
ON THE EDGE OF CIRRUS SHIELD EARLY THIS MORNING...WHILE CLEAR
SKIES PREVAIL ELSEWHERE.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM FRIDAY/...
SFC HIGH WILL PASS OVER THE STATE TODAY...MAINTAINING FAIR AND COOL
WEATHER WITH LGT WIND. UPSTREAM SATL IMAGERY AND 00Z MDL 500-300MB
RH FIELDS SUGGEST CIRRUS WILL DIM THE SUN ACROSS SOUTHERN
PA...WHILE BRIGHT SKIES PREVAIL FURTHER NORTH. ENS MEAN 925/850MB
TEMPS SHOULD SUPPORT MAX TEMPS FROM THE MID 30S OVR THE N MTNS TO
THE 40S ELSEWHERE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
CONTINUED INCREASE FOR CONFIDENCE FOR SNOW FRIDAY. ESPECIALLY
SINCE ALL MODEL GUIDANCE TRACKS FAST-MOVING SHORTWAVE THRU THE
AREA. THE SFC LOW DOES REMAIN WEAK AS IT TRACKS SOUTH OF THE
MASON DIXON LINE...COMBINATION OF WEAK SFC LOW AND HIGH OFF THE
NEW ENG COAST SHOULD CREATE ENOUGH SOUTHERLY FLOW/OVERRUNNING FOR
A LIGHT TO MOD PRECIP EVENT...ESPECIALLY IN THE PRE DAWN HOURS
OVER THE LAURELS. THE BIGGEST CAVEAT TO SNOWFALL THROUGH THE
LAURELS DURING THIS TIMEFRAME IS TEMPS ALOFT. HOWEVER CONSIDERING
THE OVERRUNNING AND THAT IT WILL WET BULB TO THE DEWPOINT...EXPECT
THAT...WHILE A MORE SATURATED SNOW...IT WILL BE AN INCREASE IN
AMOUNT.
THE LATEST HPC GUIDANCE HAS THE EPICENTER ALONG THE
LAURELS...HOWEVER GIVE THE SPEED OF THE SYSTEM...AND THAT THE SNOW
SNOW SHOULD END QUICKLY ONCE THE UPPER LEVEL TROUGH SWINGS THROUGH
AROUND 00Z SATURDAY. THE 12Z OPERATIONAL EC/GEFS/GFS HAS
INCREASED QPF FROM 00Z FRIDAY TO 00Z SATURDAY. SO CONFIDENCE IS
HIGHER FOR LARGER AMOUNTS. HOWEVER I DID TEMPER THEM CONSIDERING
THE POSSIBLE WET GROUND DUE TO RAIN STILL POSSIBLE EARLY IN THE
EVENT...HIGHER DAYTIME TEMPERATURES AND WET SNOW. HOWEVER GIVEN
THE INCREASED QPF...THE NATURE OF MILLER TYPE B EVENTS AND OVERALL
STRENGTH OF THE SYSTEM...HAVE INCREASED SNOWFALL AMOUNTS. THE
CONSALL QPF AND ASSUMPTION OF SNOW/WATER RATIOS SLIGHTLY LOWER
THAN 10/1 TRANSLATE TO LIKELY SNOW TOTALS OF 2-4 INCHES ACROSS A
LARGE PORTION OF CENTRAL PA...WITH A SWATH OF 4 TO 6 INCHES
THROUGH A PORTION OF SOUTHERN CENTRAL PA. GIVEN THE TIME OF YEAR
AND MARGINAL SFC TEMPS...MUCH OF THE ACCUM WOULD LIKELY BE ON NON-
PAVEMENT SURFACES. AS IS TYPICAL THIS TIME OF YEAR...DAYTIME SNOW
ACCUMS WILL LIKELY BE ELEVATION DEPENDENT...WITH THE HIGHEST AMTS
ON THE RIDGETOPS.
A FAIR AMT OF AGREEMENT THRU NEXT WEEKEND AMONG MED RANGE
GUIDANCE...ALL OF WHICH INDICATE A DEEP TROUGH FORMING OVR THE
NORTHEAST CONUS IN RESPONSE TO BUILDING RIDGE ON THE PACIFIC
COAST. 12Z GFS/CANADIAN/ECMWF ALL INDICATE PASSAGE OF A SHARP
COLD FRONT ON SATURDAY...FOLLOWED BY WELL BLW NORMAL TEMPS
SUNDAY/MONDAY.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
WINDS STILL UP A LITTLE HIGHER THAN I EXPECTED. WILL
MAKE SOME MINOR ADJUSTMENTS TO THE 03Z TAFS.
OVERALL WINDS WILL CONTINUE TO WEAKEN OVERNIGHT.
LOOKING AT VFR CONDITIONS THROUGH 00Z FRIDAY...WITH JUST SOME
HIGH CLDS.
CLOUDS WILL INCREASE FROM THE SOUTHWEST THURSDAY NIGHT...THEN
LOWER AND THICKEN UP LATE WITH SNOW SPREADING INTO THE SW ZONES
AROUND OR SHORTLY AFTER MIDNIGHT...AND LIKELY REACHING THE TAF
SITES /KBFD...KUNV AND KMDT/ BETWEEN 09-12Z FRIDAY.
MVFR TO IFR EXPECTED FOR MUCH OF FRIDAY IN PERIODS OF
SNOW...POSSIBLY MIXED WITH RAIN AT TIMES IN THE LOWER SUSQ VALLEY
DURING THE AFTERNOON HOURS.
EXPECT BULK OF THE PRECIPITATION TO BE IN THE FORM OF SNOW...AS
TEMPS AT 850 MB COOL DURING THE EVENT...AS LOW TRANSFERS TO THE
COAST. THIS MAKES SENSE...GIVEN HOW DRY THE AIRMASS IS...AND THAT
UPWARD MOTION WILL COOL THE AIRMASS.
MOST OF THE SNOW WILL BE EAST OF THE AREA BY 00Z SAT...EARLIER
ACROSS THE FAR WEST.
OUTLOOK...
THU NGT-FRI...MVFR/IFR LIKELY DEVELOPING IN SN ASSOCD WITH LOW
PRES TRACKING NE TO THE MID-ATLC/NORTHEAST COAST.
FRIDAY NIGHT...LINGERING DRIZZLE...FREEZING DRIZZLE OR LIGHT SNOW
EARLY AS LOW PRESSURE DEPARTS EAST OF THE MID ATL COAST WITH IFR
TO LIFR STRATUS CIGS/VSBYS...AND LIGHT/VARIABLE WIND.
SAT...MAINLY VFR...BUT MVFR/IFR PSBL NW IN -SHSN.
SUN-MON...MAINLY VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR
NEAR TERM...FITZGERALD
SHORT TERM...DEVOIR/FITZGERALD
LONG TERM...FITZGERALD/CERU
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
410 AM CDT THU MAR 19 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 409 AM CDT THU MAR 19 2015
A WEAK TROUGH ACROSS THE FAR WESTERN DAKOTAS EARLY THIS MORNING WILL
SHIFT EAST THROUGH THE FORECAST AREA THIS AFTERNOON. EXPECT A FAIR
AMOUNT OF CLOUDS AHEAD OF THE BOUNDARY...BUT WILL GRADUALLY SHIFT
SOUTH AND EAST TOWARDS THIS EVENING. STILL COULD SEE SOME HIGH
CLOUDS TONIGHT ASSOCIATED WITH A WAVE PASSING TO THE
NORTH...OTHERWISE SHOULD SEE A CLEARING TREND BEHIND THE FRONT.
GUSTY WEST TO NORTHWEST WINDS ARE EXPECTED TO DEVELOP BEHIND THE
FRONT...AND WITH THE DRY FUELS ACROSS THE AREA WILL SEE A HIGH TO
VERY HIGH FIRE DANGER.
WITH MIXY CONDITIONS...WILL SEE HIGH TEMPS 10-15 DEGREES ABOVE
NORMAL IN THE 50S TO LOWER 60S. TONIGHT...DRY AND DECREASING
CLOUDS WILL ALLOW TEMPS TO FALL BACK INTO THE LOWER 30S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 409 AM CDT THU MAR 19 2015
MAIN FOCUS FRIDAY THROUGH SATURDAY WILL BE WARM AND DRY CONDITIONS
ON FRIDAY AHEAD OF COLD FRONT...WHICH IS SET TO PUSH THROUGH THE
REGION LATE FRIDAY AND FRIDAY NIGHT. DEEP WEST-SOUTHWEST FLOW AHEAD
OF THE FRONT SHOULD RESULT IN STRONG MIXING OVER OUR DRY GROUND...
AND HAVE CONTINUED TO FAVOR WARMER END OF TEMPERATURE GUIDANCE WITH
HIGHS FROM THE LOWER 60S NORTHEAST...TO LOWER/MID 70S SOUTHWEST.
ALONG WITH THE WARM TEMPERATURES WILL BE MIXING DOWN OF DRIER DEW
POINTS...AND HAVE LOWERED AFTERNOON DEW POINTS INTO THE UPPER 20S TO
AROUND 30. THIS WILL RESULT IN MINIMUM RH LEVELS RANGING FROM NEAR
20 PERCENT IN SOUTH CENTRAL SD...TO NEAR 30 PERCENT IN SOUTHWEST MN
AND EAST CENTRAL SD. GFS/ECMWF/GEM NOW IN PRETTY GOOD AGREEMENT ON
FRONTAL TIMING...BRINGING THE BOUNDARY THROUGH THE NORTHWEST HALF OF
THE FORECAST AREA BY 00Z SATURDAY...THEN CONTINUING THROUGH THE
SOUTHEAST HALF DURING THE EVENING HOURS. THIS TIMING OF THE FRONT
SHOULD BRING A SLACKENED GRADIENT TO AREAS WITH THE MOST CRITICAL RH
VALUES DURING THE AFTERNOON...SO WHILE THESE CONDITIONS WILL BRING
AN ELEVATED FIRE DANGER TO MOST OF THE CWA...AT THIS TIME APPEARS
WIND SPEEDS WILL REMAIN BELOW CRITICAL LEVELS. FURTHER DETAIL CAN BE
FOUND IN THE FIRE WEATHER PORTION OF THIS DISCUSSION.
WINDS WILL SWING AROUND TO THE NORTHEAST LATE FRIDAY NIGHT INTO
SATURDAY. WILL SEE MORE LIMITED MIXING WITH THESE WINDS...BUT AMPLE
SUNSHINE AND DRY GROUND MAY OVERCOME THIS SOMEWHAT AND HAVE NUDGED
HIGHS UP JUST A BIT IN OUR NORTHEAST...WITH READINGS RANGING FROM
MID 40S NORTHEAST TO UPPER 50S THROUGH THE MISSOURI RIVER VALLEY.
GFS/ECMWF COMING INTO A LITTLE BETTER CONSENSUS ON EVOLUTION OF
SYSTEM SET TO AFFECT THE REGION EARLY NEXT WEEK. STRONG ISENTROPIC
LIFT AHEAD OF THE WAVE SATURDAY NIGHT/SUNDAY MORNING ACROSS MUCH OF
THE AREA...FOLLOWED BY A PERIOD OF WEAKER LIFT AND MID LEVEL DRYING
AS THE WAVE SLIDES SOUTHEAST ACROSS THE REGION. LACK OF MOISTURE
STILL A CONCERN TO START WITH...SO WILL HOLD POPS IN THE LOWER-MID
CHANCE RANGE... FOCUSING MORE ACROSS OUR NORTHEAST WHERE MOISTURE
PROFILES ARE A LITTLE MORE FAVORABLE. WITH LINGERING UNCERTAINTY IN
EXACT THERMAL PROFILES AT THIS RANGE...WILL STICK WITH GENERAL
RAIN/SNOW WORDING...WITH POTENTIAL FOR SOME ACCUMULATION ACROSS OUR
NORTHEAST FORECAST AREA. HOWEVER WILL HAVE TO MONITOR LATE SATURDAY
NIGHT/SUNDAY MORNING PERIOD FOR POSSIBLE WINTRY MIX AS TEMPERATURES
ALOFT CLIMB IN STRONG WARM ADVECTION WHILE LOW LEVEL NORTHEAST FLOW
DRAWS SOME COOLER AIR IN NEAR THE SURFACE.
GENERAL CONSENSUS MOVES THE PRECIP THREAT EAST OF THE AREA BY MIDDAY
MONDAY...BUT ANOTHER WAVE MOVES INTO THE NORTHERN PLAINS BY TUESDAY
AND BRINGS AN INCREASING PRECIP THREAT TUESDAY/TUESDAY NIGHT. LOOKS
TO BE WARM ENOUGH WITH THIS SYSTEM FOR PRIMARILY RAIN...WITH COLD
AIR MOVING IN BEHIND THE PRECIP THREAT. GFS/ECMWF BOTH SHOW A RIBBON
OF INSTABILITY AHEAD OF THE FRONT ON TUESDAY...BUT WITH DISAGREEMENT
IN TIMING OF THE WAVE/FRONT...HAVE LEFT THUNDER MENTION OUT OF THE
FORECAST FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1102 PM CDT WED MAR 18 2015
VFR CONDITIONS ARE EXPECTED TO REMAIN PREVAILING THROUGH THE TAF
PERIOD. THE EXCEPTION MAY BE SOME MVFR STRATUS LOCATED IN
NORTHERN KANSAS WHICH MAY SPREAD NORTHWARD INTO WEST CENTRAL IOWA
ONCE WINDS TURN SOUTHERLY LATE TONIGHT. MAIN CONCERN IS MAINLY
AROUND 12Z TO 16Z FOR THE KSUX TAF. THE NAM HAS BACKED AWAY FROM
THIS SOLUTION...HOWEVER THE HRRR CONTINUES TO SHOW SOME STRATUS
JUST SOUTH OF THE REGION. DECIDED TO REMOVE MENTION OF BROKEN
SKIES FROM THE KSUX TAF BUT WILL HAVE TO MONITOR THE PROGRESSION
OF THIS STRATUS LAYER OVERNIGHT.
&&
.FIRE WEATHER...
FRIDAY WILL BE A DAY OF ELEVATED FIRE DANGER OVER MUCH OF THE
REGION AS WARM AND DRY AIR MIX TO THE SURFACE AHEAD OF A COLD
FRONT. LOWEST RELATIVE HUMIDITY LEVELS EXPECTED TO REACH AROUND 20
PERCENT ACROSS THE LOWER BRULE AREA...EASTWARD THROUGH THE
MISSOURI RIVER VALLEY... RANGING UP TO AROUND 30 PERCENT FROM THE
MIDDLE BIG SIOUX VALLEY INTO SOUTHWEST MINNESOTA. AT THIS
TIME...APPEARS AS THOUGH LOCATIONS WITH THE LOWEST HUMIDITY LEVELS
WILL BE SPARED FROM THE STRONGEST WINDS...THOUGH THESE AREAS COULD
STILL SEE WINDS IN THE 15 TO 20 MPH RANGE WITH BRIEF GUSTS TO 25
MPH POSSIBLE. STRONGER WINDS FROM 20 TO 30 MPH ARE EXPECTED ACROSS
SOUTHWEST MINNESOTA AND THE IOWA GREAT LAKES...WHERE MINIMUM
HUMIDITY LEVELS WILL BE CLOSER TO 30 PERCENT. THUS WILL KEEP ALL
AREAS IN THE VERY HIGH FIRE DANGER CATEGORY FOR NOW...BUT
CONDITIONS WILL BE MONITORED CLOSELY OVER THE NEXT COUPLE OF DAYS
FOR CHANGES WHICH COULD RESULT IN FIRE WEATHER HEADLINES.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...JH
AVIATION...
FIRE WEATHER...JH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1107 PM CDT WED MAR 18 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 307 PM CDT WED MAR 18 2015
SOUTHEAST SURFACE FLOW OF AIR WILL CONTINUE TONIGHT. CLOUDS WILL
ALSO BE ON THE DECREASE THIS EVENING...ESPECIALLY ACROSS OUR
SOUTHERN ZONES. HOWEVER BOTH THE NAM AND GFS CONTINUE TO SHOW
STRATUS SNEAKING NORTHWARD INTO NORTHWEST IA AND PART OF EXTREME
NORTHEAST NEB VERY LATE TONIGHT...AND GRADUALLY NUDGING EASTWARD
THROUGH MIDDAY THURSDAY. THE NAM SOUNDING DOES SHOW A DECENT STRATUS
DEPTH WITH A STRONGLY VEERING PROFILE. THEREFORE DECIDED TO INCLUDE
SOME PATCHY DRIZZLE IN FOR LOCATIONS AROUND SIOUX CITY AND STORM
LAKE VERY LATE TONIGHT AND THURSDAY MORNING. HOWEVER WITH LOWS
PROJECTED TO STAY ABOVE FREEZING...ANY LIGHT DRIZZLE SHOULD BE
LIQUID AND NOT A PROBLEM. FOR THIS MORNINGS LOWS...AS EXPECTED THE
RAW AND BIAS CORRECTED VALUES PROVED MUCH CLOSER TO REALITY THEN THE
COLD MOS VALUES. SO FOLLOWED THIS SAME TREND FOR THURSDAY MORNINGS
LOWS AND IGNORED THE COOL MOS.
ALSO ON THURSDAY...A SHORT WAVE WILL PASS EASTWARD SQUARELY ACROSS
OUR FORECAST AREA. SURFACE WINDS WILL TURN TO THE WEST AND NORTHWEST
BEHIND THE WAVE PASSAGE GENERALLY ALONG AND WEST OF INTERSTATE 29.
CONDITIONS WILL BECOME QUITE BREEZY IN OUR WESTERN ZONES...AND ONCE
AGAIN HIGHS WILL BE MILD WITH 50S TO AROUND 60 PREVAILING.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 307 PM CDT WED MAR 18 2015
A WEAK SURFACE TROUGH/FRONTAL BOUNDARY SLIDES OFF TO THE EAST ON
THURSDAY NIGHT...AND IT WILL BE LITTLE COOLER WITH COLD AIR
ADVECTION BEHIND THE FRONT. THIS WILL PLAY OUT TO LOWS HOVERING
RIGHT AROUND 30. A MORE SIGNIFICANT FRONT WILL PUSH ACROSS THE
AREA LATER ON FRIDAY. OUT AHEAD OF THIS SYSTEM A SOUTHWESTERLY
FLOW WILL DEVELOP DURING THE DAY...AND IT WILL WARM NICELY WITH
HIGHS INTO THE LOWER 60S EAST TO THE LOWER 70S THROUGH THE
MISSOURI RIVER CORRIDOR. IT WILL BECOME BREEZY DURING THE
AFTERNOON IN A TIGHTENING GRADIENT...AND WITH THE RELATIVELY WARM
TEMPERATURES AND LOW RELATIVE HUMIDITY THROUGH THE MO RIVER VALLEY
THERE MAY BE SOME FIRE WEATHER CONCERNS. THIS WILL BE ADDRESSED
FURTHER IN A SEPARATE DISCUSSION BELOW.
HIGH PRESSURE THEN BUILDS INTO THE REGION FOR FRIDAY NIGHT AND
SATURDAY...WITH LIGHTENING WINDS AND COOLER TEMPERATURES. LOWS ON
FRIDAY NIGHT LOOK TO BE UPPER 20S TO MID 30S...WITH THERMAL
PROFILES SUPPORTING SATURDAY HIGHS IN THE 40S AND 50S.
MODELS COMING INTO A LITTLE BETTER AGREEMENT WITH PRECIPITATION
CHANCES FOR SUNDAY AND SUNDAY NIGHT AS A SHORTWAVE SLIDES ACROSS THE
REGION...WITH THE BETTER PROBABILITIES AT THIS POINT LOOKING TO BE
THROUGH THE NORTHERN AND EASTERN PORTIONS OF THE CWA. PRECIPITATION
TYPE STILL IN QUESTION WITH MODELS DIFFERING ON THERMAL
PROFILES...SO STAYED WITH RAIN/SNOW FOR NOW...THOUGH ANYTHING THAT
FALLS ON SUNDAY AFTERNOON WOULD BE PLAIN RAIN WITH SURFACE
TEMPERATURES IN THE 40S AND 50S. THERE WILL BE SLIGHT COOLING ON
MONDAY BEHIND THIS SYSTEM...TO BE FOLLOWED BY WARMING ON
TUESDAY/WEDNESDAY WITH ANOTHER SYSTEM POSSIBLY BRINGING
PRECIPITATION TO THE AREA SOMETIME IN THE TUESDAY/TUESDAY NIGHT TIME
FRAME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1102 PM CDT WED MAR 18 2015
VFR CONDITIONS ARE EXPECTED TO REMAIN PREVAILING THROUGH THE TAF
PERIOD. THE EXCEPTION MAY BE SOME MVFR STRATUS LOCATED IN
NORTHERN KANSAS WHICH MAY SPREAD NORTHWARD INTO WEST CENTRAL IOWA
ONCE WINDS TURN SOUTHERLY LATE TONIGHT. MAIN CONCERN IS MAINLY
AROUND 12Z TO 16Z FOR THE KSUX TAF. THE NAM HAS BACKED AWAY FROM
THIS SOLUTION...HOWEVER THE HRRR CONTINUES TO SHOW SOME STRATUS
JUST SOUTH OF THE REGION. DECIDED TO REMOVE MENTION OF BROKEN
SKIES FROM THE KSUX TAF BUT WILL HAVE TO MONITOR THE PROGRESSION
OF THIS STRATUS LAYER OVERNIGHT.
&&
.FIRE WEATHER...
A FRONTAL BOUNDARY IS EXPECTED TO SLIDE ACROSS THE AREA ON FRIDAY
AFTERNOON AND FRIDAY EVENING. OUT AHEAD OF THIS SYSTEM RELATIVELY
WARM TEMPERATURES WILL PREVAIL...AND AFTERNOON RELATIVE HUMIDITY
VALUES ARE EXPECTED TO DROP INTO THE RANGE OF 20 TO 25 PERCENT
THROUGH THE MISSOURI RIVER CORRIDOR. SOUTHWESTERLY WINDS WILL PICK
UP DURING THE EARLY AFTERNOON...THOUGH GENERALLY REMAIN SUSTAINED
AT 15 TO 20 MPH. AT THIS POINT...THE FRONTAL TIMING WOULD SUGGEST
THAT THE LOWEST RH VALUES/HIGHER WINDS WILL NOT COINCIDE AS THE
GRADIENT SLACKENS OVER SOUTH CENTRAL SD IN THE AFTERNOON AND
WINDS BEGIN TO TAPER DOWN. THIS WILL HAVE TO BE WATCHED OVER THE
NEXT COUPLE OF DAYS HOWEVER...AS FRONTAL PASSAGE TIMING
DIFFERENCES COULD RESULT IN A FIRE WEATHER HEADLINE AT SOME POINT.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...MJ
LONG TERM...JM
AVIATION...
FIRE WEATHER...JM
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
403 AM MDT THU MAR 19 2015
.SYNOPSIS...
SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE TODAY THROUGH SATURDAY
AS AN UPPER LOW SOUTHWEST OF ARIZONA SLIDES ACROSS NORTHERN MEXICO
AND TO THE BIG BEND REGION SATURDAY. TEMPERATURES WILL REMAIN NEAR
NORMAL. DRIER WEST FLOW DEVELOPS LATER SATURDAY AND LASTS THROUGH
MID WEEK OF NEXT WEEK. THIS WILL KEEP SKIES MOSTLY CLEAR AND
TEMPERATURES WILL CLIMB TO WELL ABOVE NORMAL. AFTERNOONS WILL BE
BREEZY ON TUESDAY AND WEDNESDAY.
&&
.DISCUSSION...
UPPER LOW NOW JUST WEST OF THE NORTHERN BAJA WITH SOME SUBTROPICAL
MOISTURE STREAMING AHEAD OF THE LOW OVER MOST OF ARIZONA AND NEW
MEXICO. RADAR SHOWS WESTERN CWA (LUNA COUNTY WEST) FILLING IN WITH
SHOWERS. HI-RES MODELS SHOWING A FAVORED AREA OF THE CWA TODAY WEST
OF EL PASO. LATEST HRRR SHOWING DECENT QPF DEMING WEST THIS MORNING
WITH RAINFALL AMOUNTS APPROACHING ONE-HALF INCH. NAM 12 ALSO HITS
THE BOOTHEEL AND GILA HARD WITH RAIN TODAY. POPS IN GRIDS DEFINITELY
SHOW THIS FAVORING...THOUGH KEEP LOW POPS IN FOR THE REST OF THE
AREA. SHOWERS TO CONTINUE TONIGHT THOUGH LESS COVERAGE EXPECTED.
MODELS SHOW WEAK BACK DOOR COLD FRONT MOVING IN LATE TONIGHT/EARLY
FRIDAY MORNING...PROBABLY ONLY MAKING IT AS FAR WEST AS THE RIO
GRANDE VALLEY. THIS COULD BE A FOCUS FOR SHOWERS FRIDAY...BUT MODELS
MOSTLY BEARISH (NAM/ECMWF) ON RAINFALL FRIDAY. BOTH THESE MODELS
SHOW DRY SLOTTING AND RAINFALL BECOMING QUITE SPOTTY. GFS STILL MORE
BULLISH WITH NOT MUCH SIGN OF ANY DRY SLOTTING.
BY SATURDAY MORNING THE UPPER LOW IS JUST WEST OF THE BIG BEND AND
WESTERN PARTS OF THE CWA SHOULD BEGIN CLEARING. STILL SLIGHT CHANCE
OF SHOWERS EL PASO EAST WHERE MOISTURE IS STILL AVAILABLE...BUT THIS
SHOULD MOVE EAST OUT OF THE AREA BY SATURDAY AFTERNOON.
REST OF FORECAST PERIOD RESEMBLES A MORE TYPICAL MARCH AS DRY
WESTERLIES DEVELOP BEHIND THE EXITING LOW. TEMPERATURES SHOULD CLIMB
SMARTLY WITH THIS DRIER FLOW...WITH MANY LOWLAND AREAS REACHING 80+
DEGREES BY TUESDAY. AFTERNOONS WILL BECOME BREEZY TUESDAY AND
WEDNESDAY.
&&
.AVIATION...VALID 19/12Z-20/12Z...
VFR GENERALLY THROUGH PERIOD...WITH SKIES SCT/BKN120 LAYERS TO 300.
SCATTERED -SHRA BKN080...MOSTLY FREQUENT WEST OF EL PASO. FOR THE
MORNING HOURS THROUGH ABT 15Z...FEW AREAS OF VSBY LESS THAN ONE MILE
IN FOG. AFT 18Z...A FEW THUNDERSTORMS POSSIBLE. WIND GUSTS OF 25-35
KTS POSSIBLE WITH THESE STORM.
&&
.FIRE WEATHER...
AN UPPER LOW CURRENTLY MOVING INTO THE BAJA REGION WILL PROGRESS
VERY SLOWLY EASTWARD THROUGH SATURDAY. THIS WILL KEEP A CHANCE FOR
SHOWERS AND THUNDERSTORMS OVER THE FORECAST AREA. DECENT LOW LEVEL
MOISTURE WILL REMAIN IN PLACE KEEPING RELATIVE HUMIDITIES ABOVE 20
PERCENT. AS THE UPPER LOW EXITS TO THE EAST...ZONAL FLOW WILL SETUP
WITH OCCASIONAL BREEZY TO WINDY CONDITIONS BY TUESDAY AND
WEDNESDAY...BUT AT THIS TIME LOOKING TO REMAIN BELOW RED FLAG WIND
CRITERIA. TEMPERATURES WILL ALSO BE ON THE INCREASE WITH HIGHS
POSSIBLY TOPPING 80 DEGREES FOR THE FIRST TIME THIS YEAR OVER THE
LOWLANDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
EL PASO 70 51 71 49 73 / 20 20 20 20 20
SIERRA BLANCA 69 49 66 47 68 / 20 20 20 30 40
LAS CRUCES 69 47 70 45 72 / 30 20 20 20 20
ALAMOGORDO 70 47 69 43 72 / 30 30 30 20 30
CLOUDCROFT 47 34 49 35 53 / 40 40 40 30 30
TRUTH OR CONSEQUENCES 66 46 67 43 70 / 40 30 30 20 20
SILVER CITY 56 44 59 42 64 / 50 30 40 30 20
DEMING 69 45 70 44 73 / 40 20 30 20 20
LORDSBURG 66 44 69 42 71 / 40 30 30 20 10
WEST EL PASO METRO 70 52 71 51 73 / 20 20 20 20 20
DELL CITY 72 44 68 43 71 / 20 20 20 20 40
FORT HANCOCK 72 50 71 48 72 / 20 20 20 20 40
LOMA LINDA 66 50 66 48 66 / 20 20 20 20 30
FABENS 70 49 71 47 73 / 20 20 20 20 30
SANTA TERESA 70 49 70 48 72 / 20 20 20 20 20
WHITE SANDS HQ 68 50 68 48 71 / 20 20 20 20 20
JORNADA RANGE 70 44 70 42 72 / 30 30 30 20 20
HATCH 69 46 69 44 73 / 30 30 30 20 10
COLUMBUS 67 49 69 47 71 / 40 20 20 20 10
OROGRANDE 69 50 68 47 71 / 20 20 20 20 30
MAYHILL 57 36 55 36 60 / 30 30 40 30 30
MESCALERO 57 35 57 36 60 / 40 40 40 30 30
TIMBERON 56 38 56 38 59 / 30 30 40 20 30
WINSTON 57 39 58 39 64 / 50 30 40 30 30
HILLSBORO 65 46 64 44 66 / 40 30 30 30 20
SPACEPORT 69 42 69 41 72 / 40 30 30 20 20
LAKE ROBERTS 58 39 61 37 64 / 60 30 50 30 30
HURLEY 59 43 61 42 66 / 40 30 30 30 20
CLIFF 65 42 67 40 71 / 50 30 40 30 20
MULE CREEK 63 40 65 38 68 / 50 30 40 30 20
FAYWOOD 64 45 64 44 66 / 40 30 30 30 20
ANIMAS 67 46 69 45 73 / 40 30 30 20 10
HACHITA 68 45 70 43 72 / 40 30 30 20 10
ANTELOPE WELLS 67 44 70 43 72 / 40 30 30 20 10
CLOVERDALE 65 46 67 44 68 / 50 30 30 20 10
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
17 HEFNER
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
325 AM MST THU MAR 19 2015
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.
&&
.SYNOPSIS...
CLOUDY CONDITIONS AND COOLER TEMPERATURES WILL BE IN OUR AREA
THROUGH TODAY. SOME LIGHT SHOWERS WITH EVEN A RUMBLE OF THUNDER MAY
BE SEEN. A DRYING...AND WARMING TREND WILL BE SEEN BEGINNING FRIDAY
AND CONTINUING INTO THE MIDDLE PART OF NEXT WEEK.
&&
.DISCUSSION...
TODAY TROUGH FRIDAY... A RATHER UNSETTLED PATTERN CONTINUES THIS
MORNING ACROSS OUR CWA. CURRENT RADAR AND SATELLITE IMAGERY
CONTINUES TO SHOW SCATTERED-NUMEROUS SHOWERS ACROSS MUCH OF
ARIZONA...WITH EVEN A FEW THUNDERSTORMS ACROSS SOUTHWEST
ARIZONA...WHICH HAS LIKELY BROUGHT UP TO A HALF INCH...OR EVEN A
LITTLE MORE TO A FEW ISOLATED SPOTS. THE COMPLEX UPPER LOW CENTER
THAT HAS BROUGHT US THIS WET WEATHER IS NOW CENTERED OVER EXTREME
NORTHERN BAJA...AND IS FORECAST TO MOVE SLOWLY EASTWARD JUST SOUTH
OF THE INTERNATIONAL BORDER OVER THE NEXT 48-72 HOURS. THE FOCUS OF
THE HEAVIEST RAINFALL OVER THE LAST 6-9 HOURS HAS BEEN OVER LA
PAZ...NORTHERN YUMA...AND EXTREME WESTERN MARICOPA...AS A SPOKE OF
VORTICITY ROTATES SLOWLY WESTWARD AROUND THE MAIN LOW CENTER.
LIGHTER SHOWER ARE ALSO BEING OBSERVED AT THIS TIME ACROSS THE
REMAINDER OF MARICOPA COUNTY AS WELL...BUT RAINFALL AMOUNTS OVER THE
PAST FEW HOURS IN THAT REGION HAVE BEEN PRETTY MEAGER...MAINLY IN
THE TRACE-0.05 INCH RANGE...AS THERE HAS BEEN A BIT OF
DRYSLOTING/LOSS OF VERTICAL MOTION BEHIND THE AFOMENTIONED VORTICITY
LOBE. THE LATEST HRRR AND NAM SHORT-RANGE MODELS ARE NOW INDICATING
THAT THE HEAVIEST SHOWERS WILL LIKELY CONTINUE ACROSS SOUTHWEST AZ
AND NORTHWEST MARICOPA COUNTY...AND EVEN MOVE BACK INTO PASTS OF SE
CA BETWEEN NOW AND 18Z...THEN SHIFT BACK EASTWARD INTO MARICOPA/GILA
COUNTIES BETWEEN 18-00Z AS ANOTHER WEAK SHORTWAVE/COLD POOL ROTATES
AROUND THE MAIN LOW CENTER. ISOLATED THUNDERSTORMS WILL LIKELY
DEVELOP AGAIN THIS AFTERNOON AS SOLAR HEATING AND SLIGHTLY COLDER
AIR ALOFT DESTABILIZE THE COLUMN. A DRYING TREND IS THEN EXPECTED TO
BEGIN TO WORK ITS WAY EASTWARD ACROSS THE REGION THIS EVENING AS THE
MAIN TROF AXIS SHIFTS SLOWLY OFF TO THE EAST AND PWATS BEGIN TO
DROP...WITH MOST OF THE SHOWER ACTIVITY SHIFTING INTO SOUTHERN GILA
COUNTY BY LATE TONIGHT. FRIDAY WILL SEE MORE ISOLATED-SCATTERED
SHOWER ACTIVITY ACROSS SOUTHERN GILA COUNTY AS A BIT OF MOISTURE IS
WRAPPED BACK WESTWARD INTO THAT REGION. THE CLOUDS AND SHOWERS WILL
HOLD TEMPERATURES WELL INTO THE 70S ACROSS THE LOWER DESERTS OF
SOUTH-CENTRAL ARIZONA...WITH SOME LOW 80S ACROSS SW AZ AND SE
CA...WITH SOME MODEST WARMING ON FRIDAY AS SKIES BEGIN TO CLEAR
SATURDAY THROUGH THURSDAY...A WARMING AND DRYING TREND STILL APPEARS
ON TAP FROM SATURDAY ONWARD INTO AT LEAST THE MIDDLE OF NEXT WEEK AS
BOTH THE GFS AND EURO MODELS CONTINUE TO BUILD FLAT RIDGING BACK
OVER THE REGION AS THE AFOREMENTIONED UPPER TROF MOVES OFF WELL TO
OUR EAST...WITH LOWER DESERT HIGHS LIKELY REACHING 90 DEGREES BY
EARLY NEXT WEEK. SOME COOLING IS POSSIBLE BY THE END OF NEXT WEEK AS
THE NEXT MAJOR LOW-WAVE TROF BRUSHES BY WELL TO OUR NORTH AND EAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
THICK MIDLEVEL CIGS WILL PREVAIL THROUGH THIS AFTERNOON...
POTENTIALLY BRIEFLY TOUCHING AS LOW AS 6K-8K FT LATE THIS MORNING
AND INTO THE EARLY AFTERNOON. VERY LIGHT SHOWERS/SPRINKLES WILL
CONTINUE INTO THE AFTERNOON...HOWEVER SHOULD NOT AMOUNT TO MUCH MORE
THAN A TRACE AND PROVIDE MINIMAL IMPACT. ONLY MODERATE CONFIDENCE IN
ANY WIND SHIFTS THROUGH THE EARLY AFTERNOON...THOUGH DIRECTIONS
SHOULD FAVOR AN EASTERLY COMPONENT. WINDS SHOULD RETURN TO THE WEST
BY MID TO LATE AFTERNOON. THERE IS AN OUTSIDE CHANCE OF A
THUNDERSTORM DURING THE AFTERNOON BUT CONFIDENCE TOO LOW...AND
COVERAGE TOO ISOLATED...TO MENTION THUNDER IN THE UPCOMING MORNING
TAF PACKAGE. OF COURSE SHOULD A STORM DEVELOP THE WINDS WILL BECOME
SQUIRRELY AND UNCERTAIN...AND LOCALLY GUSTY.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
EXTENSIVE THICK CIGS IN AN 8K-12K FT RANGE WILL ONLY BEGIN TO
SCATTER BY THIS AFTERNOON. THERE MAY BE A FEW SHOWERS AT THE TAF
SITES THROUGH LATE MORNING...BUT THREATS FOR PRECIP SHOULD BE MOSTLY
OVER AFTER 19Z. WINDS WILL STAY RATHER LIGHT/VARIABLE AT BOTH SITES
TODAY BUT WILL LIKELY FAVOR THE SOUTH AT KBLH.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY... AN AREA OF LOW PRESSURE WILL EXIT TO
THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO FILTER INTO THE
LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE TEENS ACROSS THE
CENTRAL AND WESTERN DESERTS. THERE WILL BE A LINGERING SLIGHT CHANCE
OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF PHOENIX...MAINLY TO THE
EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A DRY WESTERLY FLOW ALOFT
WILL DOMINATE THE WEATHER PATTERN AS HIGHER PRESSURE ALOFT SLOWLY
BUILDS ACROSS THE REGION. HIGH TEMPERATURES WILL STEADILY CLIMB WITH
THE WARMER LOWER DESERTS REACHING THE UPPER 80S TO LOW 90S BY
MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS EXPECTED OVER THE
NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH DESERTS READINGS
BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST HALF OF NEXT
WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY THROUGH MONDAY
WITH WINDS INCREASING TUESDAY AND WEDNESDAY...BECOMING BREEZY FROM
THE WEST DURING THE AFTERNOON HOURS EACH DAY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA
AVIATION...MO/CB
FIRE WEATHER...CB
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
852 AM PDT THU MAR 19 2015
.SYNOPSIS...
UPPER LEVEL LOW PRESSURE SYSTEM OVER NORTHERN BAJA WILL BRING A FEW
ADDITIONAL SHOWERS AND THUNDERSTORMS THIS AFTERNOON...MAINLY FOR THE
INLAND VALLEYS AND MOUNTAINS. HIGHER PRESSURE ALOFT WILL BRING
DRY...WARMER WEATHER FRIDAY THROUGH MONDAY...WITH DAY-TIME HIGHS
SEVERAL DEGREES ABOVE NORMAL. NIGHT AND MORNING MARINE LAYER STRATUS
WILL CONTINUE OVER THE COAST AND PORTIONS OF THE VALLEYS. SOME
OFFSHORE FLOW AND MORE WARMING IS POSSIBLE BY MID NEXT WEEK.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING
ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN
BERNARDINO COUNTIES...
AN UPPER LEVEL LOW...CURRENTLY SOUTH OF THE BORDER ACCORDING TO
WATER VAPOR SATELLITE...WILL CONTINUE TO MOVE TO THE SOUTH AND EAST
THROUGH FRIDAY. BEFORE IT LEAVES...SOME LINGERING MOISTURE AND
INSTABILITY COULD BRING ANOTHER ROUND OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS TODAY...MAINLY TO THE MOUNTAINS AND VALLEYS.
RADAR CURRENTLY SHOWS MOST OF THE SHOWER ACTIVITY OCCURRING OVER
ARIZONA...WITH SOME LIGHT SHOWERS/SPRINKLES MOVING NORTHEAST TO
SOUTHWEST OVER THE SAN BERNARDINO COUNTY MOUNTAINS AND RIVERSIDE
COUNTY. CURRENT GPS PRECIPITABLE WATER SENSORS OVER THE REGION
INDICATE ABOUT 0.8 TO 0.9 INCHES OF PRECIPITABLE WATER...WHICH IS
ENOUGH MOISTURE FOR PRECIPITATION. THE 12Z HRRR SHOWS THE SAN DIEGO
COUNTY VALLEYS GETTING SOME HEAVY SHOWERS AND THUNDERSTORMS FOR A
FEW HOURS DURING THE MID TO LATE AFTERNOON HOURS TODAY DUE TO DAY-
TIME SURFACE HEATING. MEANWHILE...VISIBLE SATELLITE SHOWS PATCHY
MARINE LAYER STRATUS OVER THE VALLEYS THIS MORNING...WHILE
INTERESTINGLY ENOUGH THE COASTAL AREAS ARE PRETTY MUCH DEVOID OF
STRATUS. ANY LOW LEVEL STRATUS LIKELY WILL CLEAR OUT BY LATE
MORNING.
TONIGHT INTO FRIDAY...AS THE LOW MOVES FARTHER FROM THE AREA TO THE
SOUTHEAST MUCH DRIER AIR MOVES IN OVER THE AREA BRINGING AN END TO
THE SHOWER/THUNDERSTORMS. THE MARINE LAYER SHOULD REMAIN
ESTABLISHED...WITH STRATUS LIKELY MOVING INTO THE COAST AND VALLEYS
AGAIN. TEMPERATURE LOOK TO BE SEVERAL DEGREES HIGHER ON FRIDAY DUE
TO CLEARING SKIES AND A RIDGE WHICH STARTS TO BUILD OVER THE AREA.
WEATHER CONDITIONS WILL BE SIMILAR SATURDAY THROUGH MONDAY WITH WEAK
RIDGING ALOFT...ONSHORE FLOW AT THE SURFACE...NIGHT AND MORNING
MARINE LAYER STRATUS MOVING INTO THE COAST AND WESTERN VALLEY
AREAS...AND TEMPERATURES SEVERAL DEGREES ABOVE NORMAL. A TROUGH
MOVING INTO THE PACIFIC NORTHWEST LATE MONDAY INTO EARLY TUESDAY
LOOKS TO BRING SOME STRONGER ONSHORE FLOW...AND SOME GUSTY WEST
WINDS TO THE MOUNTAINS AND DESERTS.
SLIGHTLY COOLER CONDITIONS WILL PREVAIL TUESDAY WITH WEAK OFFSHORE
FLOW STARTING TO DEVELOP. WEDNESDAY INTO THURSDAY...A WEAK AND DRY
TROUGH WILL MOVE OVER SOUTHERN CALIFORNIA...AND THERE IS THE
POTENTIAL FOR SOME MODERATE OFFSHORE FLOW AND INCREASED WARMING.
THIS WOULD ERADICATE THE MARINE LAYER.
&&
.AVIATION... 191530Z...PATCHY STRATUS OVER THE COAST/VALLEYS...WITH
BASES AROUND 2300 FT MSL AND TOPS TO 3200 FT MSL...WILL SLOWLY CLEAR
THIS MORNING. VIS OF 3-6 SM HZ IN THE INLAND EMPIRE WILL IMPROVE TO
P6SM BY LATE THIS MORNING. -SHRA/-TSRA WILL BE POSSIBLE THROUGH
EARLY THIS EVENING...MAINLY OVER INLAND AREAS. SMALL HAIL...REDUCED
VIS FROM RAIN...FREQUENT LIGHTNING AND STRONG UP/DOWN DRAFTS WILL BE
POSSIBLE NEAR STORMS.
MARINE LAYER STRATUS...WITH BASES NEAR 1500 FT MSL AND TOPS TO 2500
FT MSL...WILL REDEVELOP ALONG THE COAST THIS EVENING AND PUSH AROUND
15-30 SM INLAND BY EARLY FRIDAY MORNING. VIS OF 3-5 SM BR WILL BE
POSSIBLE WHERE STRATUS NEARS HIGHER TERRAIN. LOW CLOUDS MAY LIFT 200-
400 FT OVERNIGHT DUE TO A COASTAL EDDY.
&&
.MARINE... 830 AM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH
SUNDAY. BREEZY NORTHWEST WINDS WILL DEVELOP LATE MONDAY OVER THE
OUTER COASTAL WATERS...WITH GUSTS TO 20-25 KT POSSIBLE.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...HARRISON
AVIATION/MARINE...JJT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
429 AM MDT THU MAR 19 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM MDT THU MAR 19 2015
...RAIN AND MTN SNOW TO CONTINUE TODAY BEFORE WINDING DOWN LATER
TONIGHT...
UPPER TROF AXIS CURRENTLY EXTENDS FROM ND...SOUTHWESTWARD ACROSS WY
AND UT...WITH BROAD CLOSED LOW CENTERED ACROSS THE NRN BAJA
PENINSULA. RADAR ECHOES HAVE BLOSSOMED OVER THE SOUTHEAST
MTS/ADJACENT PLAINS EARLY THIS MORNING AS VORT MAX WHICH EJECTED OUT
OF THE DESERT SOUTHWEST LIFTS TO THE NORTHEAST. HRRR SEEMS TO HAVE
A FAIRLY GOOD HANDLE ON THE TIMING OF THE PRECIP...WHICH LIFTS OFF
TO THE NORTHEAST THIS MORNING...WHILE FILLING IN ACROSS EL PASO
COUNTY...THEN SPREADING BACK SOUTHWARD DURING THE MORNING HOURS AS
THE FRONT DROPS SOUTHWARD...AND FORCING FROM THE UPPER TROF AXIS
MOVES IN. THUS...EXPECT WIDESPREAD RAIN AND MOUNTAIN SNOWS TO FILL
IN ALONG THE SOUTHERN I-25 CORRIDOR THROUGH 15Z...AND CONTINUE INTO
THE EARLY AFTERNOON WITH FOCUS SHIFTING INTO THE SOUTHWEST MTS
DURING THE AFTERNOON AS INSTABILITY FROM THE TROF AXIS ACTS ON
FAIRLY GOOD FETCH OF MOISTURE FROM THE SOUTH. SUSPECT THAT
ADVISORIES ACROSS NORTHEAST PORTIONS OF THE AREA (TELLER/NRN
FREMONT) MAY BE ABLE TO BE TAKEN DOWN BY 00Z AS HRRR AND RAP SHOW
PRECIPITATION DWINDLING QUICKLY DURING THE LATE AFTERNOON HOURS.
SOUTHERN AND CENTRAL MOUNTAIN AREAS WILL CONTINUE TO SEE SNOW INTO
THE EVENING HOURS AS DEEP EASTERLY UPSLOPE FLOW CONTINUES. SNOW
LEVELS ARE PROBABLY AROUND 7500 FEET AS OF 4 AM THIS MORNING...BASED
ON WEB CAMS AROUND THE PIKES PEAK REGION. SNOW LEVELS MAY BRIEFLY
DROP TO AROUND 6500 FEET THIS MORNING...BUT BY IN LARGE WILL
PROBABLY HOVER AROUND 7000-7500 FEET THROUGH MOST OF THE DAY. SNOW
AMOUNTS WILL BE HIGHLY DEPENDENT ON GETTING THE SNOW LEVELS CORRECT.
AND ANYTIME YOU ADD THE CONVECTIVE ELEMENT...THIS CAN LEAD TO
INTENSE SNOWFALL RATES WITH QUICK ACCUMULATIONS OF HEAVY WET SNOW.
MODELS STILL LOOK OVERDONE WITH THE AREAL COVERAGE OF THESE HEAVIER
SNOWFALL AMOUNTS...BUT MAGNITUDE IS CERTAINLY POSSIBLE WITH SNOWFALL
RATES OF OVER AN INCH AN HOUR POSSIBLE AT TIMES. CURRENT SUITE OF
HIGHLIGHTS STILL LOOKS ON TRACK. SOME CONCERN AREAS FOR TODAY WILL
BE THE LOWER ELEVATIONS OF TELLER COUNTY AND THE WET MOUNTAINS...AS
NORTHEAST FACING SLOPES COULD PICK UP CLOSE TO A FOOT IF SNOW LEVELS
STAY LOW ENOUGH FOR LONG ENOUGH. HOWEVER...AREAL COVERAGE OF THESE
HIGHER AMOUNTS DO NOT APPEAR TO JUSTIFY UPGRADING TO WARNINGS AT
THIS POINT. HOWEVER...HEAVY WET SPRING LIKE SNOWS OFTEN LEAD TO
HIGHLY CHANGEABLE FORECASTS...SO THIS WILL CONTINUE TO BE MONITORED.
MEANWHILE...RAINFALL ON THE LOWER SLOPES OF THE WALDO SHOULD SWITCH
OVER TO SNOW IN THE NEXT HOUR OR TWO. RAINFALL RATES HAVE REMAINED
UNDER .15 PER HOUR...AND DO NOT EXPECT THEM TO EXCEED THIS
RATE...EVEN IF SNOW SWITCHES BACK TO RAIN LATER THIS MORNING...SO
NOT EXPECTING A FLASH FLOOD THREAT FOR WALDO. THAT SAID...SOME
CREEKS AND DRAINAGES MAY EXPERIENCE SOME MINOR RUNOFF THROUGH THE
DAY.
SOUTHWEST MOUNTAINS AND CENTRAL MOUNTAINS SHOULD SEE AROUND 4-8
INCHES OF SNOW THIS AFTERNOON AND EVENING AS TROF AXIS MOVES ACROSS.
INSTABILITY MAY BE SUFFICIENT FOR AN ISOLATED EMBEDDED THUNDERSTORM
ACROSS THE SOUTHWEST MOUNTAINS THIS AFTERNOON AS WELL...WHICH COULD
BRING SOME LOCALLY HEAVY SNOWFALL AT TIMES. IN ADDITION...EASTERLY
UPSLOPE FLOW MAY ALSO SERVE TO FOCUS PRECIPITATION ALONG THE EASTERN
SLOPES OF THE EASTERN SAN JUANS. HOWEVER...SNOW LEVELS LOOK EVEN
HIGHER OUT THAT WAY...AROUND 8KFT...SO HEAVIER ACCUMULATIONS SHOULD
BE CONFINED TO THE HIGHER ELEVATIONS. AGAIN...CURRENT ADVISORIES
STILL LOOK ON TARGET. PRECIPITATION WILL TAIL OFF FROM NORTH TO
SOUTH OVERNIGHT. -KT
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 428 AM MDT THU MAR 19 2015
FRIDAY...THE UPPER LOW OVER AZ AND OLD MEXICO IS FORECAST TO WEAKEN
AND GRADUALLY SLIDE TO THE EAST ON FRIDAY...ALLOWING PRECIPITATION
TO DIMINISH FROM NORTH TO SOUTH FRIDAY MORNING. SHOWER ACTIVITY WILL
LINGER THE LONGEST OVER THE SW MTS AND SOUTHERN SANGRES. LOOK FOR
TEMPS TO REBOUND BACK INTO THE 50S TO MID 60S ACROSS MUCH OF THE
AREA.
SATURDAY THROUGH MONDAY...LONGER RANGE MODELS AGREE ON KEEPING A
GENERAL WESTERLY FLOW ALOFT ACROSS THE STATE OVER THE WEEKEND AND
INTO THE NEXT WORK WEEK. A COUPLE OF DISTURBANCES PASSING TO THE
NORTH WILL BRING THE THREAT OF SHOWERS TO THE HIGHER TERRAIN...BUT
MODELS ARE NOT ON THE SAME PAGE FOR TIMING OF THESE.
THEREFORE...DECIDED TO LEAN TOWARDS THE GFS AT THIS TIME WHICH
INDICATES ISOLATED SHOWERS FOR THE S MTS ON SAT...A STRONGER
DISTURBANCE AFFECTING MAINLY THE CENTRAL MTS AND RAMPART RANGE ON
SUNDAY...THEN A DRY MONDAY. LOOK FOR WARMER TEMPS ALL THREE
DAYS...WITH 70S ACROSS THE E PLAINS AND 60S FOR THE HIGH VALLEYS.
TUESDAY AND WEDNESDAY...MODELS ARE TRENDING TOWARDS A MUCH STRONGER
UPPER TROUGH DROPPING OUT OF CANADA ON TUESDAY...BRINGING PCPN BACK
TO THE FORECAST AREA TUES NIGHT THROUGH WEDNESDAY. INCREASED WINDS
AND WAA TUE WOULD MEAN A VERY WARM DAY WITH MAX TEMPS PUSHING 80F ON
THE PLAINS...THEN ABOUT A 10-15 DEGREE COOLDOWN FOR WED. EC AND GFS
MODELS HINT AT THIS SOLUTION...BUT HAVE DIFFERING TIMING AND SYSTEM
STRENGTH SO FORECAST CONFIDENCE IS LOW AT THIS TIME. MOORE
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 428 AM MDT THU MAR 19 2015
IFR CONDITIONS CAN BE EXPECTED IN AND NEAR THE MOUNTAINS TODAY WITH
WIDESPREAD SNOW SHOWERS. HOWEVER...THE TAF SITES ARE EXPECTED TO
REMAIN PREDOMINANTLY MVFR WITH RAIN SHOWERS THROUGH THE DAY. KCOS
COULD SEE A BRIEF MIX WITH SNOW WHICH MAY BRIEFLY CAUSE CIGS AND VIS
TO APPROACH IFR THIS MORNING. KALS WILL LIKELY SEE PRECIP IN THE
FORM OF RAIN...WHICH WILL SPREAD BACK IN LATE THIS MORNING THROUGH
THIS AFTERNOON WITH VFR TO BRIEF MVFR CONDITIONS POSSIBLE. SHOWERS
WILL DIMINISH FROM NORTHEAST TO SOUTHWEST THROUGH THE LATE AFTERNOON
AND EVENING HOURS WITH VFR CONDITIONS EXPECTED BY LATE EVENING FOR
KCOS AND KPUB. DEPENDING ON THE AMOUNT OF CLEARING WHICH TAKES
PLACE OVERNIGHT...KALS COULD SEE SOME PATCHY FOG DEVELOP EARLY
FRIDAY MORNING...BUT PROBABILITY LOOKS LOW AT THIS POINT DUE TO
LIKELIHOOD OF SOME PERSISTENT MID/HIGH CLOUDINESS. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ082.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT FRIDAY FOR COZ072-074-079.
WINTER STORM WARNING UNTIL 6 AM MDT FRIDAY FOR COZ073-075-080.
WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ058-
060-076-081.
WINTER WEATHER ADVISORY FROM NOON TODAY TO 6 AM MDT FRIDAY FOR
COZ066-068.
&&
$$
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...KT
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NWS MELBOURNE FL
900 AM EDT THU MAR 19 2015
.DISCUSSION... UA DATA FROM THE CANAVERAL SOUNDING SHOWS PRESENCE OF
A PARTIALLY BUOYANT AIRMASS THAT SHOULD BE ABLE TO OVERCOME MODEST
INHIBITION DURING THE COURSE OF THE AFTERNOON. CONSIDERABLE HIGHER
CLOUDS WL DELAY HEATING SOMEWHAT. ISOLD MARINE SHOWERS THIS MORNING
WL TRANSITION TO THE COAST WITH SOME ADTL DEVELOPMENT INLAND AS A
BREEZE BOUNDARY SETS UP FROM EARLY AFTN ONWARD. LTST HRRR GUID SHOWS
SOME DEVELOPMENT OF ECSB BOUNDARY RELATED PCPN WEST OF I-95 EARLY IN
AFTERNOON WITH ANOTHER ROUND OF EARLY EVENING DEVELOPMENT OF
SCT/ISOLD SHOWERS W OF METRO ORLANDO DUE TO A BREEZE COLLISION
TOWARD DUSK. NO FORECAST UPDATE PLANNED ATTM.
TODAY/TONIGHT...(PREV DISC) WEAK FRONTAL BOUNDARY OVER THE REGION
WILL LIFT NORTHWARD LATER TODAY INTO TONIGHT AS MID LEVEL S/W
CROSSING THE DEEP SOUTH DEVELOPS A WEAK LOW OFF THE SOUTHEAST U.S.
COAST. LOW LEVEL E/SE FLOW WILL BECOME MORE SOUTHERLY INTO THE AFT
AS THIS BOUNDARY LIFTS NORTH WITH SOME INCREASE IN MOISTURE
EXPECTED. FLOW WILL BE LIGHT ENOUGH FOR SEA BREEZE BOUNDARIES TO
DEVELOP AND MOVE INLAND INITIATING ISO/SCT SHOWERS ACROSS THE AREA.
BEST RAIN CHANCES (UP TO 30-40%) WILL EXIST FROM OSCEOLA/NRN BREVARD
COUNTY NORTHWARD WHERE GREATER MOISTURE EXISTS AND WHERE ENHANCED
SUPPORT FOR LIFT WILL RESIDE FROM PASSING S/W AND A LATE DAY SEA
BREEZE COLLISION ACROSS THE INTERIOR. RAIN CHANCES THEN DECREASE
INTO THE EVENING AND END OVER THE REGION BY MIDNIGHT.
&&
.AVIATION...FOG/STRATUS SHOULD BURN OFF BY MID MORNING WITH VFR
CONDS GENERALLY EXPECTED THROUGH THE DAY. ISO/SCT SHRA WILL BE
POSSIBLE ALONG THE INLAND MOVING EAST COAST SEA BREEZE INTO THE AFT
WITH BEST CHANCES ACROSS NRN TERMINALS WHERE BETTER MOISTURE WILL
RESIDE. PATCHY FOG PRODUCING IFR/MVFR CONDS WILL ONCE AGAIN BE
POSSIBLE LATE TONIGHT.
&&
.MARINE...
TODAY/TONIGHT...WEAK FRONTAL BOUNDARY OVER THE AREA WILL EVENTUALLY
LIFT NORTHWARD LATER TODAY INTO TONIGHT. ONSHORE WINDS UP TO 15-20
KNOTS OVER THE OFFSHORE WATERS NORTH OF THE CAPE WILL SLOWLY
DECREASE AS FLOW VEERS TO THE SOUTHEAST AND EVENTUALLY SOUTH TO
SOUTHWEST INTO TONIGHT.
WNAWAVE GUIDANCE CONTINUES TO BE OVERESTIMATING WAVE HEIGHTS BY A
FOOT SO HAVE LIMITED SEAS OFFSHORE TO 6 FEET. WILL KEEP SMALL CRAFT
EXERCISE CAUTION HEADLINES FOR THESE POOR BOATING CONDS.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
JP/TES
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
956 AM CDT Thu Mar 19 2015
.UPDATE...
ISSUED AT 954 AM CDT THU MAR 19 2015
Narrow west-east bands of echoes continue to appear on radar,
mostly near the I-70 corridor. Some periodic light rain has been
reported, but there were also some sleet reports as well near
Effingham. Some more widespread rain showers were occurring in
central and west central Missouri, and latest runs of the HRRR and
NAM show this increasing as it moves eastward this afternoon ahead
of a shortwave that will be moving out of the Dakotas. Have sent
some refinements of the rain chances in the grids/zones, focusing
the best chances from about mid afternoon through late evening. No
significant changes made to temperatures.
&&
.SHORT TERM...(Today)
ISSUED AT 327 AM CDT THU MAR 19 2015
Dissipating short-wave tracking into the Tennessee River Valley has
spread light rain as far north as south-central Illinois early this
morning, with 07Z/2am radar imagery showing precip just south of a
Jacksonville to Paris line. 00Z KILX upper air sounding featured
plenty of dry air below 700mb, which is effectively keeping the
precip from spreading any further north. Recent radar trends and
HRRR forecasts support this as well, showing the light rain staying
across the far southern KILX CWA through mid-morning. As the
initial wave ripples by to the south, a second northern-stream
wave currently evident on water vapor imagery over the western
Dakotas will approach from the northwest later in the day. All
models suggest this feature will draw moisture currently across
Missouri/southern Illinois back northward this afternoon. Given
initially dry low-level air mass and continued easterly flow, think
this will be a slow process. Have therefore slowed the northward
spread of precip, delaying it across much of the CWA until
afternoon. In fact, areas around Rantoul and Danville may stay dry
until closer to evening. Further west, have raised PoPs to likely
along/west of a Peoria to Mattoon line this afternoon. Due to
extensive cloud cover, light easterly winds, and eventually light
rain...have undercut the warm MAV guidance by several degrees. High
temperatures will range from the middle 40s far southwest around
Jacksonville to around 50 degrees along/east of I-57.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 327 AM CDT THU MAR 19 2015
Light rain will be ongoing across much of the area this evening, as
short-wave tracks into the southern Great Lakes. As this feature
moves further east, the rain will come to an end from west to east
overnight. Total rainfall through tonight will generally range from
one tenth to one quarter of an inch.
High pressure will build into the region on Friday, providing dry
and seasonably warm conditions with highs well into the 50s. Even
warmer weather is expected on Saturday, as southwesterly winds
increase in advance of an approaching cold front. Boundary will pass
through Saturday afternoon/evening, but before it does, high
temperatures will climb into the lower to middle 60S. Once front
exits, a chilly air mass will settle into the area for early next
week.
00Z Mar 19 models continue to show a clipper system approaching from
the northwest Sunday night into Monday, with minor timing
differences noted. Given presence of initially dry air mass beneath
surface high pressure on Sunday, think precip with this feature will
be delayed. As a result, will keep Sunday evening dry with chance
PoPs spreading across the western half of the CWA overnight. With
850mb temps in the 0 to -5C range and ample evaporational cooling
occurring, think precip type will be snow or a rain/snow mix. This
wintry precip will continue into Monday morning before surface temps
warm sufficiently to support all rain by midday. The clipper will
be weakening as it tracks southeastward across the area and with
temps quickly climbing above freezing Monday morning, am expecting
little or no snow accumulation.
Once this system passes, cool/dry weather will be on tap for Tuesday
before yet another wave and its associated cold front approach on
Wednesday. GFS/ECMWF are in good agreement concerning timing of
this system, with both models spreading rain into Illinois Tuesday
night into Wednesday. Will carry high chance PoPs accordingly,
with southerly flow ahead of the cold front pushing high temps
back into the upper 50s and lower 60s on Wednesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 607 AM CDT THU MAR 19 2015
VFR conditions will prevail at all TAF sites this morning and into
early afternoon. Then as clouds lower during the afternoon, will
include VCSH to catch any light rain showers than might occur. As
the rain does begin later this afternoon and into early this
evening, cig heights are expected to drop to 3 kft or less. As the
rain gets steadier, the vis will drop to around 5SM at all sites.
The pcpn will continue during the evening, but then end from
northwest to eastward at midnight or later. Should end at PIA
first and then last at CMI. Will keep fog in the forecast, based
on light winds and some low level moisture. Winds will be east to
southeasterly at 12kts or less during the day, but then become
light and variable through the rest of the period tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
609 AM CDT THU MAR 19 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 232 AM CDT THU MAR 19 2015
THE MOST SIGNIFICANT FORECAST CHALLENGES FOR THE SHORT TERM ARE 1)
VISIBILITY RESTRICTION IN FOG THIS MORNING; 2) EVOLUTION OF LIGHT
RAIN DURING THE DAY AND TIMING THE CESSATION OF RAIN; 3)
TEMPERATURES TODAY; AND 4) PATCHY FOG THURSDAY NIGHT. INTERACTION
BETWEEN FLOW AROUND AN UPPER LEVEL CYCLONE CENTERED OVER THE
NORTHERN GULF OF CALIFORINA AND UPPER LEVEL TROUGHS RIPPLING THROUGH
THE NORTHERN BRANCH OF THE WESTERLIES ACROSS THE NORTHERN UNITED
STATES IS CONTRIBUTING TO METEOROLOGICAL UNCERTAINTY IN THE CENTRAL
PLAINS. A SURFACE CYCLONE WAS CENTERED IN NORTHEAST NEW MEXICO EARLY
THIS MORNING WITH A DEVELOPING WARM FRONT EXTENDING FROM THE CYCLONE
INTO CENTRAL TEXAS. AN UPPER LEVEL TROUGH WAS EVIDENT ON SATELLITE
IMAGERY FROM SOUTH CENTRAL COLORADO TO EASTERN NEW MEXICO, AND
ANOTHER STRONGER UPPER LEVEL TROUGH WAS APPROACHING WESTERN MEXICO.
THE TROUGH APPROACHING WESTERN MEXICO WILL PROPAGATE NORTHEAST INTO
WESTERN TEXAS THIS AFTERNOON, AND THE SURFACE CYCLONE WILL MOVE
ALONG THE BAROCLINIC ZONE NEAR THE RED RIVER INTO NORTHERN TEXAS
THIS EVENING. THE UPPER LEVEL TROUGH FROM SOUTHERN COLORADO INTO
EASTERN NEW MEXICO WILL MOVE INTO WESTERN KANSAS THIS MORNING AND
WILL WEAKEN IN THE CONFLUENT UPPER LEVEL FLOW OVER THE CENTRAL
PLAINS.
MOIST UPSLOPE FLOW HAS FAVORED DEVELOPMENT OF WIDESPREAD STRATUS IN
CENTRAL AND EASTERN KANSAS, AND THE AREA OF STRATUS WILL CONTINUE TO
PROPAGATE WEST THROUGH THE EARLY MORNING HOURS. THE BEST OPPORTUNITY
FOR FOG WITH VISIBILITIES BELOW A MILE WILL BE NEAR THE WEST EDGE OF
THE MOISTURE FIELD FROM NORTH CENTRAL INTO WEST CENTRAL KANSAS. WITH
THE WEAKNESS OF THE LOW LEVEL FLOW AND EXTENSIVE MID AND HIGH LEVEL
CLOUDINESS TO INTERFERE WITH RADIATIONAL COOLING, SURFACE COOLING
WEST OF THE RICHER MOISTURE FIELD LIKELY WILL NOT BE SUFFICIENT TO
ALLOW THE GROUND TO COOL ENOUGH TO SUPPORT EVOLUTION OF DENSE FOG AS
THE HIGHER DEWPOINTS GRADUALLY ADVECT WEST. WIDESPREAD VISIBILITIES
OF ONE TO TWO MILES SEEM LIKELY.
SCATTERED LIGHT SHOWERS HAVE BEEN PERSISTENT IN ADVANCE OF A MID
LEVEL DEFORMATION ZONE FROM EASTERN INTO SOUTH CENTRAL KANSAS DURING
THE NIGHT AND LIKELY WILL CONTINUE INTO THE MORNING HOURS. AS THE
UPPER LEVEL TROUGH MOVES FROM COLORADO AND NEW MEXICO INTO WESTERN
KANSAS THIS MORNING, A WEAK MID LEVEL CIRCULATION IS LIKELY TO
DEVELOP IN SOUTHWEST KANSAS ALONG A SHARP H7 BAROCLINIC ZONE AND
GRADUALLY TO WEAKEN AS IT MOVES EAST DURING THE DAY. A JET STREAK
EAST OF THE GULF OF CALIFORNIA UPPER LEVEL LOW WILL INCREASE IN
STRENGTH TODAY, AND UPPER LEVEL DIVERGENCE IN THE LEFT EXIT REGION
OF THE JET STREAK WILL ENHANCE UPWARD VERTICAL MOTION IN SOUTHWEST
KANSAS. THE COMBINATION OF UPPER LEVEL DIVERGENCE AND WEAK
ISENTROPIC LIFT OVER THE MID LEVEL BAROCLINIC ZONE WILL SUPPORT
DEVELOPMENT OF WIDESPREAD LIGHT RAIN THIS MORNING. AS THE JET STREAK
PROPAGATES EAST THIS AFTERNOON, UPWARD VERTICAL MOTION WILL
DECREASE, AND ISENTROPIC DOWNGLIDE WILL EVOLVE IN THE MID LEVELS OF
THE ATMOSPHERE. RAIN WILL END FROM NORTH TO SOUTH LATE HIS AFTERNOON
AND EARLY THIS EVENING AS SUBSIDENCE BEGINS AND DRY AIR IN THE LOW
LEVELS INVADES WESTERN KANSAS.
TEMPERATURES TODAY WILL BE SLOW TO RISE WITH EXTENSIVE CLOUD COVER
AND PRECIPITATION. THE WARMEST READINGS LIKELY WILL BE IN NORTHERN
KANSAS, WHERE CLOUDINESS WILL ERODE ENOUGH TO ALLOW AT LEAST SOME
SOLAR RADIATION TO REACH THE SURFACE. MOST HIGHS WILL BE IN THE 40S.
WINDS WILL BECOME LIGHT AND VARIABLE THIS EVENING WITH A WEAK
SURFACE HIGH PRESSURE RIDGE IN KANSAS AND WILL BECOME LIGHT WEST
AFTER MIDNIGHT. MODEL SOUNDINGS ARE VERY DRY ABOVE THE SURFACE
TONIGHT AND ARE NOT SUPPORTIVE OF FOG FORMATION; HOWEVER, THE MOIST
BOUNDARY LAYER SHOULD PRODUCE SOME REALLY HEAVY DEW AND PATCHY
RADIATION FOG IN LOW LYING AREAS IS POSSIBLE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 244 AM CDT THU MAR 19 2015
A COLD FRONT WILL MOVE SOUTH ACROSS THE NORTHERN PLAINS ON FRIDAY
AS AN UPPER LEVEL TROUGH EXITS CENTRAL CANADA AND MOVES INTO THE
WESTERN GREAT LAKES REGION. AHEAD OF THIS COLD FRONT 850MB
TEMPERATURES ARE FORECAST BY THE NAM AND GFS AT 00Z SATURDAY TO
RANGE FROM +9C IN SOUTH CENTRAL KANSAS TO NEAR +13C ACROSS
NORTHWEST KANSAS. BASED ON THESE TEMPERATURES LATE FRIDAY THE
PREVIOUS FORECAST STILL LOOKS ON TRACK WITH HIGHS RANGING FROM THE
MID 60S TO LOWER 70S.
THE WEAK COLD FRONT WILL MOVE INTO NORTHERN KANSAS LATE FRIDAY
NIGHT WHERE IT WILL BRIEFLY BECOME STATIONARY ON SATURDAY. A
TROUGH OF LOW PRESSURE WILL DEEPEN NEAR THE COLORADO BORDER DURING
THE DAY AS A WEAK UPPER LEVEL DISTURBANCE APPROACHES THE AREA FROM
THE WEST. ACROSS NORTH CENTRAL KANSAS THE 850MB TEMPERATURE TREND
FROM 00Z SATURDAY TO 00Z SUNDAY INDICATED AT 1 TO 2 WARMUP.
FURTHER WEST/SOUTHWEST THE 850MB TEMPERATURES WARM 4 TO 6C OVER
THE SAME TIME FRAME. GIVEN THESE TEMPERATURE TRENDS THE PREVIOUS
FORECAST STILL LOOKS ON TRACK WITH TEMPERATURES BEING WARMER ON
SATURDAY COMPARED TO FRIDAY WITH THE LARGER WARMUP BEING ACROSS
SOUTHWEST KANSAS.
ON SATURDAY NIGHT A WEAK UPPER LEVEL DISTURBANCE WILL BEGIN TO
CROSS THE CENTRAL HIGH PLAINS WITH 700-500MB LAPSE RATES BETWEEN
00Z SUNDAY TO 06Z SUNDAY RANGING FROM 7 TO AROUND 7.5 C/KM. GFS
DOES ATTEMPT TO GENERATE SOME PRECIPITATION AHEAD OF THIS WEEKEND
SYSTEM BUT IT ALSO HAS BETTER MOISTURE RETURN OCCURRING OVER
WESTERN KANSAS. ECMWF KEEPS THE BETTER MOISTURE FURTHER SOUTH
CLOSER TO THE WEAKENING UPPER LEVEL TROUGH THAT WILL BE CROSSING
NORTH TEXAS. AT THIS TIME GIVEN SOME CONCERN ON MOISTURE OVER
WESTERN KANSAS SATURDAY NIGHT WILL ONLY INCREASE CLOUD COVER AT
THIS TIME AHEAD OF THIS WEAK UPPER LEVEL DISTURBANCE.
ON SUNDAY THIS MOISTURE RETURN OVER WESTERN KANSAS WILL GET
SHUNTED EAST AS THE SURFACE TROUGH OF LOW PRESSURE MOVES INTO
CENTRAL KANSAS. ANOTHER WEAK UPPER DISTURBANCE WILL THEN CROSS THE
CENTRAL HIGH PLAINS SUNDAY NIGHT INTO EARLY MONDAY AS THE COLD
FRONT FINALLY MOVE ACROSS WESTERN KANSAS. THIS NEXT FEATURE
APPEARS TO HAVE SLIGHTLY BETTER UPPER LEVEL DYNAMICS BASED ON THE
LOCATION OF THE 70-80KT 250MB JET STREAK EARLY MONDAY MORNING.
MOISTURE HOWEVER MAY BE MORE QUESTIONABLE ACROSS FAR WESTERN
KANSAS NORTH OF THE COLD FRONT. MID LEVEL INSTABILITY STILL
PRESENT BASED ON THE 700MB TO 500MB LAPSE RATES SO GIVEN BETTER
JET DYNAMICS LATE SUNDAY NIGHT INTO MONDAY WILL RETAIN A MENTION
OF SHOWERS AND ISOLATED THUNDERSTORMS AS THIS NEXT WEAK FEATURE
CROSSES WESTERN KANSAS.
AN UPPER LEVEL RIDGE AXIS AXIS WILL CROSS THE ROCKIES MONDAY AND
TUESDAY AS AN UPPER LEVEL TROUGH EXITS THE EASTERN PACIFIC AND
BEGINS TO CROSS THE PACIFIC NORTHWEST. AS THIS UPPER RIDGE AXIS
CROSSES THE ROCKIES A WESTERLY DOWNSLOPE FLOW WILL IMPROVE ACROSS
WESTERN KANSAS. BASED ON IMPROVING DOWNSLOPE FLOW AND RIDGING
ALOFT EARLY NEXT WEEK WILL STAY CLOSE TO THE LATEST
CREXTENDFCST_INIT WITH TEMPERATURES CLIMBING BACK AT LEAST INTO
THE LOW TO MID 70S BY TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 607 AM CDT THU MAR 19 2015
LIGHT RAIN WILL INCREASE IN AREAL COVERAGE ACROSS SOUTHWEST
KANSAS THIS MORNING AND THEN CONTINUE THROUGH THE LATE AFTERNOON.
MODEL SOUNDINGS, RAP, AND HRRR ALL SUGGEST THAT THE LIFR/IFR CLOUD
BASES WILL BEGIN TO GRADUALLY IMPROVE LATE MORNING AND CONTINUE
THROUGH THE LATE AFTERNOON. AT THIS TIME CEILINGS ARE EXPECTED TO
IMPROVE INTO THE LOW VFR CATEGORY BETWEEN 20Z THURSDAY AND 00Z
FRIDAY. AT DDC AND GCK MVFR VISIBILITIES FROM FOG AND LIGHT RAIN
WILL BE LIKELY UNTIL MID AFTERNOON. AT HYS MVFR VISIBILITIES ARE
EXPECTED TO IMPROVE BY 18Z. WINDS WILL BE MAINLY NORTHEAST AT 10
KNOTS OR LESS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 45 34 69 40 / 90 40 0 0
GCK 46 32 68 38 / 90 30 0 0
EHA 46 36 64 40 / 90 40 0 0
LBL 46 34 66 39 / 90 50 0 0
HYS 53 32 71 38 / 40 0 0 0
P28 48 36 70 43 / 90 40 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RUTHI
LONG TERM...BURGERT
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1014 AM CDT THU MAR 19 2015
.UPDATE...
BASED ON RADAR TRENDS AND THE 12Z SOUNDING HAVE LOWERED POPS
ACROSS THE AREA TO SLIGHT CHANCE...AND COMPLETELY REMOVED THE
MENTION OF RAIN FROM THE FORECAST FOR TONIGHT AND TOMORROW
MORNING. HAVE ALSO INCREASED THE FOG COVERAGE FOR TONIGHT...AS
LIGHT BOUNDARY LAYER WINDS AND A HIGH DEWPOINT AIRMASS CREATE
FAVORABLE CONDITIONS FOR FOG TO FORM. SIMILAR CONDITIONS ARE
EXPECTED FOR TOMORROW NIGHT. TEMPERATURES ARE ON TRACK AT MOST
LOCATIONS. HOWEVER...CONDITIONS ARE WARMING FASTER THAN
ANTICIPATED ON THE MISSISSIPPI GULF COAST. EXPECT TO SEE A
SEABREEZE FORM BY EARLY AFTERNOON...WHICH SHOULD KEEP TEMPERATURES
MORE STEADY ALONG THE COAST IN THE AFTERNOON HOURS. 32
&&
.PREV DISCUSSION... /ISSUED 415 AM CDT THU MAR 19 2015/
SHORT TERM...
A WARM AND MUGGY NIGHT WILL GIVE WAY TO ANOTHER WARM SPRING DAY
FOR THE FORECAST AREA TODAY AS A FRONTAL BOUNDARY STALLS OVER THE
FORECAST AREA. A FEW SHOWERS HAVE DEVELOPED THIS MORNING ALONG
THIS FRONTAL BOUNDARY AND THIS COULD SERVE AS A FOCUS FOR SOME
SHOWER DEVELOPMENT THROUGHOUT THE DAY AS TEMPERATURES ARE EXPECTED
TO CLIMB INTO THE LOWER 80S. WITH THIS BOUNDARY IN PLACE AND AMPLE
MOISTURE IN PLACE...A FEW SHOWERS AND MAYBE EVEN A THUNDERSTORM
COULD DEVELOP THIS AFTERNOON. SOME OF THE SHORT RANGE MODELS THE
HI-RES ARW AND NMM...AND EVEN THE HRRR SHOW ON AND OFF SHOWERS
THROUGHOUT THE DAY WITH MORE ACTIVITY IN THE AFTERNOON MAINLY
NORTH OF LAKE PONTCHARTRAIN. HAVE CARRIED ONLY SLIGHT CHANCE POPS
BUT WE COULD SEE AN UPDATE AT SOME POINT TODAY IF SHOWERS BECOME
MORE NUMEROUS. OVERALL IT SHOULD BE A RELATIVELY QUIET DAY AND
AGAIN FOR FRIDAY. 13/MH
LONG TERM...
THE NEXT ORGANIZED CHANCE FOR RAIN LOOKS TO COME THIS WEEKEND
BEGINNING SATURDAY MORNING WITH THE BULK OF THE PRECIPITATION
OCCURRING SATURDAY NIGHT INTO SUNDAY MORNING. A FAIRLY STRONG
SOUTHERN STREAM UPPER LEVEL LOW WILL BEGIN TO PUSH INTO TEXAS FROM
NORTHERN MEXICO AND THIS ENERGY WILL MOVE OVER THE FORECAST AREA
OVER THE WEEKEND. THE PREVIOUS FORECAST LOOKS TO BE ON TRACK AS
THIS SYSTEM WILL BRING RAIN AND SOME THUNDERSTORMS TO THE REGION.
SOME OF THESE SHOWERS AND STORMS COULD BE DECENT RAIN PRODUCERS AS
DEEP MOISTURE AND THE DEPTH OF THE WARM CLOUD LAYERS SHOULD ALLOW
FOR PERIODS OF HEAVY RAIN SATURDAY AND SUNDAY. RIGHT NOW THIS DOES
NOT LOOK LIKE A SEVERE WEATHER SETUP FOR THE AREA. HAVE INCREASED
RAIN CHANCES FOR THE ENTIRE AREA AND HAVE PUSHED INTO THE
CATEGORICAL RANGE FOR AREAS ALONG AN NORTH OF LAKE PONTCHARTRAIN
FOR SATURDAY NIGHT. THE SYSTEM WILL PUSH THROUGH ON SUNDAY AND WE
WILL STILL HAVE SOME LINGERING SHOWERS ON SUNDAY. THE UPPER LOW
MOVES OFF TO THE EAST ON MONDAY AS WE DRY OUT AND HIGH PRESSURE
MOVES INTO THE AREA. TEMPERATURES WILL COOL BACK TO MORE NORMAL
READINGS IN THE LOWER 70S FOR MONDAY AND TUESDAY...AND OVERNIGHT
LOWS WILL BE NEAR AVERAGE IN THE 50S. A FAIRLY STRONG MID AND
UPPER LEVEL RIDGE WILL DOMINATE ON TUESDAY AND WEDNESDAY...AND THE
STRONG SUBSIDENCE ALOFT WILL KEEP CLEAR SKIES IN PLACE ACROSS THE
REGION 13/MH
AVIATION...
CURRENTLY MAJORITY OF THE TERMINALS ARE STILL
EXPERIENCING VFR CONDITIONS BUT THIS MAY CHANGE DURING THE EARLY
MORNING HRS. MVFR AND TEMPO IFR CIGS AND VSBYS COULD DEVELOP.
CONDITIONS SHOULD THEN RETURN TO VFR SHORTLY AFTER SUNRISE. /CAB/
MARINE...
OVER THE NEXT 4 DAYS LOOK FOR BENIGN CONDITIONS TO DOMINATE THE
COASTAL WATERS WITH VARIABLE WINDS OF 10 KNOTS OR LESS EXPECTED AS
A BROAD AREA OF HIGH PRESSURE REMAINS PARKED OVER THE NORTHERN
GULF OF MEXICO AND A WEAK STALLED BNDRY LIES JUST NORTH OF THE
COAST. SEAS WILL GENERALLY RANGE FROM 1 TO 3 FEET...AND DO NOT
EXPECT ANY SIGNIFICANT MARINE IMPACTS DURING THIS PERIOD. THINGS
SHOULD FINALLY CHANGE LATE SUNDAY AS A SFC LOW MOVES ACROSS THE
REGION AND DRAGS THE FRONT SOUTH LEADING TO MODERATE OFFSHORE
WINDS SUN NIGHT AND INTO NEXT WEEK. /CAB/
DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 78 61 80 63 / 20 20 40 40
BTR 81 62 82 64 / 20 20 30 40
ASD 80 63 81 65 / 20 10 30 30
MSY 80 63 80 65 / 20 10 20 20
GPT 77 63 77 64 / 20 10 30 20
PQL 80 62 79 64 / 20 10 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
958 AM EDT THU MAR 19 2015
.SYNOPSIS...
STRONG LOW PRESSURE WILL CONTINUE TO MOVE EAST OF THE MARITIMES
TODAY. HIGH PRESSURE WILL BUILD IN FROM THE WEST TONIGHT AND
CREST OVER THE REGION FRIDAY. LOW PRESSURE SYSTEMS FROM THE MID
ATLANTIC STATES AND CENTRAL CANADA WILL APPROACH LATE FRIDAY NIGHT
AND TRACK SOUTH AND NORTH OF THE REGION BY SAT NIGHT.
&&
.NEAR TERM /THROUGH FRIDAY/...
945 AM UPDATE: LATEST IR ENHANCED SATELLITE IMAGERY SHOWED CLOUDS
DROPPING SOUTHWARD ACROSS NORTHERN MAINE DOWN INTO EAST-CENTRAL
AREAS. STREAMLINE TRAJECTORIES AT 12Z SHOWED A NICE CONVERGENCE
AXIS IN PLACE ACROSS THE NORTH AND NORTHWEST AREAS W/A SFC TROF IN
PLACE. 12Z UA SHOWED A TROF DROPPING SE FROM SOUTHERN CANADA INTO
NORTHERN MAINE W/NW FLOW SETTING UP AGAIN. STREAMER ACTION CAN BE
SEEN ON THE VISIBLE SATELLITE IMAGERY AS WELL OFF THE OPEN ST.
LAWRENCE. THIS ACTION WILL ALLOW FOR SOME LIGHT SNOW/FLURRIES INTO
THE AFTERNOON. THIS IS WELL SUPPORTED BY THE RAP SOUNDINGS SHOWING
MOISTURE TRAPPED BENEATH 6K FT. SB CAPE CLIMBS TO 30-40 JOULES
W/SOME STEEPENING OF THE LAPSE RATES, ESPECIALLY BELOW 3 KM.
THEREFORE, DECIDED TO ADD POPS UP TO 30% ACROSS THE NORTHERN AND
EASTERN AREAS FOR SOME LIGHT SNOW/FLURRIES.
AS MENTIONED BY THE MIDNIGHT CREW, THE STEEPER LAPSE RATES WILL
LEAD TO GUSTY WINDS INTO THE AFTERNOON W/POTENTIAL OF 40 MPH OVER
HIGHER TERRAIN. KEPT PATCHY BLOWING SNOW IN PLACE. HRLY TEMPS
WERE ADJUSTED TO MATCH THE LATEST OBS, WHICH SHOWS A WARMER TREND.
AFTERNOON MAXES MAY NEED TO BE BOOSTED ESPECIALLY DOWNEAST TO THE
COAST W/MORE SUN. WILL TAKE A LOOK AT THINGS AFTER 11 AM. R
A MDTLY STRONG SFC PRES GRAD AND WINDS IN THE 925 TO 850 MB LAYER
ABOUT 25 KT XPCTD TO CONT OVR THE REGION INTO AFTN...THE POTENTIAL
OF BRISK GUSTY WINDS TO 35 MPH AND EVEN 40+ MPH OVR HIER TRRN
EXISTS LATER THIS MORN INTO MID AFTN WHEN SFC-1000M LAPSE RATES
BECOME STEEP. WIND GUSTS OF 35+ MPH WILL STILL BE CAPABLE OF
PRODUCING PATCHY BLSN OVR OPEN TRRN AREAS...BUT ALL IN ALL
CONDITIONS WILL STILL BE AN IMPROVEMENT OVR YSTDY WHICH FEATURED
MORE WIDESPREAD BLSN. HI TEMPS THIS AFTN WILL CONT VERY COLD...BUT
NOT QUITE AS COLD AS YSTDY AFTN.
WITH BOTH THE SFC PRES GRAD AND WINDS ALF SLACKENING AFT SUNSET...
WINDS SHOULD DECREASE TO A LGT BREEZE OVR ERN PTNS OF THE FA...
AND EVEN DECOUPLE OVR BROAD WRN VLYS LATE TNGT AS THE AXIS OF THE
SFC HI APCHS THIS PTN OF THE REGION BY ERLY FRI MORN. THE
POTENTIAL OF SHALLOW SFC-BASE INVSN OVR THE BROAD WRN VLYS SHOULD
ALLOW FOR LOW TEMPS TO FALL BLO ZERO OVR THIS AREA...WITH SINGLE
DIGITS OVR THE REST OF THE N AND CNTRL AND ARND 10 ABV FOR
DOWNEAST AREAS BY ERLY FRI MORN.
FRI WILL BEGIN SUNNY...THEN CLDNSS FROM SFC LOWS AND ASSOCIATED
S/WVS FROM THE MID ATLC STATES AND CNTRL CAN BEGIN TO ARRIVE FRI
AFTN...SPCLY OVR WRN PTNS OF THE FA. WITH MUCH LIGHTER WINDS HI
TEMPS SHOULD CONT TO RECOVER ON FRI...REACHING THE LOWER TO MID
30S ACROSS ALL XCPT HIGHEST TRRN LCTNS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
PRECIPITATION CHANCES INCREASE FOR THE END OF THE WEEK AS AN
UPPER TROUGH APPROACHES FROM THE NORTHWEST. THE LATEST RUN OF THE
ECMWF HAS COME INTO LINE WITH THE REST OF THE GUIDANCE WITH THE
HANDLING OF THIS SYSTEM. MODEL CONSENSUS DEVELOPS A NORTHERN
STREAM SURFACE LOW WHICH WOULD TRACK ACROSS SOUTHERN
QUEBEC/NORTHERN MAINE, BRINGING ITS ATTENDANT COLD FRONT TO OUR
WESTERN AREAS BY SATURDAY EVENING. THIS SOLUTION ALSO DEVELOPS A
SOUTHERN LOW BUT KEEPS IT WELL SOUTH OF NOVA SCOTIA. THIS PATTERN
WOULD MEAN A MIX OF LIGHT RAIN AND SNOW FOR OUR FORECAST AREA
DURING THE DAY SATURDAY. HAVE GONE WITH A BLEND THAT LEANED
HEAVILY ON THE GFS AND ALSO INCLUDED THE PREVIOUS FORECAST TO
MAINTAIN SOME CONSISTENCY. THE MAIN CHANGE WAS TO INCREASE QPF A
BIT OVER NORTHERN AND WESTERN MAINE WHILE LOWERING IT DOWNEAST AND
OVER THE WATERS. TEMPERATURES WILL BE IN THE LOWER TO MID 30S ON
SATURDAY, SO EXPECT THAT DOWNEAST WILL CHANGE OVER TO RAIN FOR A
TIME DURING THE AFTERNOON. ELSEWHERE, RAIN WILL AT LEAST MIX WITH
SNOW, EXCEPT IN THE HIGHER TERRAIN IN THE NORTH WOODS. SNOW
ACCUMULATION WILL BE AROUND AN INCH AT MOST, THOUGH THE HIGHER
TERRAIN MAY SEE AROUND 2 INCHES BY SATURDAY EVENING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE AFOREMENTIONED COLD FRONT WILL CROSS THE STATE FROM WEST TO
EAST SATURDAY NIGHT. THIS WILL ALLOW PRECIPITATION TO TAPER OFF TO
SHOWERS WHILE CHANGING OVER TO ALL SNOW. A MUCH COLDER AIRMASS
WILL FOLLOW, WITH BRISK NORTHWEST WINDS AND WELL BELOW NORMAL
TEMPERATURES FOR SUNDAY THROUGH MONDAY. LINGERING SNOW SHOWERS
WILL BE POSSIBLE OVER FAR NORTHERN AREAS EARLY NEXT WEEK AS WELL.
WE`LL START TO SEE SOME IMPROVEMENT ON TUESDAY AS HIGH PRESSURE
CRESTS OVER THE REGION. THE HIGH WILL MOVE OFFSHORE ON WEDNESDAY,
PLACING NEW ENGLAND UNDER SOUTHWEST FLOW AND ALLOWING TEMPERATURES
TO FINALLY GET CLOSE TO NORMAL.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR XPCTD THRU FRI...WITH PERHAPS BRIEF INTERVALS OF
SC MVFR CLGS THIS MORN OVR NRN MOST TAF SITES...SPCLY KFVE.
SHORT TERM: VFR CONDITIONS FRIDAY NIGHT AND EARLY SATURDAY WILL
GIVE WAY TO MVFR/LOCAL IFR BY SATURDAY AFTERNOON AS LIGHT RAIN AND
SNOW CROSS THE REGION. THE NORTHERN TERMINALS, ESPECIALLY KFVE,
HAVE THE BEST CHANCES OF REMAINING ALL SNOW DURING THE DAY
SATURDAY. MVFR TO LINGER THROUGH AT LEAST 06Z SUNDAY, WITH IFR
POSSIBLE AT KFVE DUE TO SNOW SHOWERS COMING OFF THE SAINT
LAWRENCE. CONDITIONS WILL IMPROVE DURING THE DAY SUNDAY WITH ALL
SITES TO BE VFR BY 00Z MONDAY.
&&
.MARINE...
NEAR TERM: WILL CONT WITH THE GALE WRNG OVR OUR WATERS WITH LLVL
COLD ADVCN WNW WINDS...DUE TO EXPIRE AT NOON...AT WHICH POINT AN
INTERIM SCA WILL LIKELY BE NEEDED FOR THE REMAINDER OF THE AFTN
INTO ERLY EVE...SPCLY OVR THE OUTER MZS WATERS. THE FZGSPY ADV FOR
MDT FZSPY WOULD ALSO EXPIRE OVR OUR WATERS AT NOON...FOLLOWED BY
A PD OF LGT FZSPY ROUGHLY CORRESPONDING WITH SCA CONDITIONS.
AFTWRDS...WE ANTICIPATE NO HDLNS LATER TNGT CONTG THRU FRI.
INITIALLY ERLY THIS MORN...OBSVD WV HTS ARE RUNNING ABOUT 1 TO 2
FT ABV FCST WW3 WV GUIDANCE...THEN WE SLOWLY MERGE TO WW3 GUIDANCE
LATE TNGT INTO FRI.
SHORT TERM: GALE HEADLINES WILL LIKELY BE NEEDED ACROSS THE
WATERS FOR EARLY NEXT WEEK. A STRONG COLD FRONT WILL CROSS THE
WATERS LATE SATURDAY, WITH MUCH COLDER AIR SPREADING IN ITS WAKE.
THIS WILL RESULT IN GUSTY NORTHWEST WINDS OF 20 TO 25 KT, WITH
GUSTS OF 35-40 KT. SEAS WILL BE 5 TO 8 FEET. SMALL CRAFT
CONDITIONS WILL BE MET BY MIDNIGHT SUNDAY MORNING, WITH GALES TO
PREVAIL THROUGH THE DAY SUNDAY INTO SUNDAY EVENING. THERE WILL BE
SOME IMPROVEMENT MONDAY, THOUGH WINDS WILL LIKELY STAY ABOVE SMALL
CRAFT CRITERIA UNTIL MONDAY NIGHT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...FREEZING SPRAY ADVISORY UNTIL NOON EDT TODAY FOR ANZ050>052.
GALE WARNING UNTIL NOON EDT TODAY FOR ANZ050>052.
&&
$$
NEAR TERM...HEWITT/VJN
SHORT TERM...HASTINGS
LONG TERM...HASTINGS
AVIATION...HEWITT/VJN/HASTINGS
MARINE...HEWITT/VJN/HASTINGS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
622 AM EDT THU MAR 19 2015
.SYNOPSIS...
STRONG LOW PRESSURE WILL CONTINUE TO MOVE EAST OF THE MARITIMES
TODAY. HIGH PRESSURE WILL BUILD IN FROM THE WEST TONIGHT AND
CREST OVER THE REGION FRIDAY. LOW PRESSURE SYSTEMS FROM THE MID
ATLANTIC STATES AND CENTRAL CANADA WILL APPROACH LATE FRIDAY NIGHT
AND TRACK SOUTH AND NORTH OF THE REGION BY SAT NIGHT.
&&
.NEAR TERM /THROUGH FRIDAY/...
610 AM UPDATE: LATEST RADAR REF IMAGERY AND SFC OBS FROM KCAR
STILL INDICATE SCT FLURRIES INTERSECTING FAR NE AROOSTOOK COUNTY
ATTMS ERLY THIS MORN...WITH LATEST HRRR MODEL OUTPUT SUGGESTING
THAT ALL SN SHWR ACTIVITY EXITING OUT FA VIA NB BY 8 AM EDT.
OTHERWISE...FCST LOWS WERE UPDATED BY SUBTRACTING TWO DEG F FROM
6 AM EDT OBSVD TEMP GRID AND POSTING THE RESULT AT 7 AM. THIS
RESULTED IN LOWS NOT AS PREVIOUSLY COLD OVR ERN ME ERLY THIS MORN
DUE TO PERSISTENT CLD CVR. FCST HRLY TEMPS WERE THEN UPDATED INTO
THE AFTN TO UNCHGD FCST HI TEMPS POSTED AT 4-5 PM EDT. WINDS...
WHICH HAVE DROPPED OFF SOME ERLY THIS MORN...WILL INCREASE
SOMEWHAT LATER THIS MORN AS SFC TEMPS RISE...RESULTING IN
STEEPENING SFC-500M LAPSE RATES AND BETTER MIXING OF STRONGER
WIND ALF TO THE SFC AS WIND GUSTS.
ORGNL DISC: SAT IMAGERY STILL SHOWS CLDNSS ACROSS NRN AND ERN
PTNS OF THE FA FROM THE SLOWLY RETREATING SFC/UPPER LOW OVR THE
ERN CAN MARITIMES...BUT BELIEVE THIS CLD DECK IS RELATIVELY THIN.
MOST OF THIS CLDNSS WILL MOVE E OUT OF THE REGION THIS AFTN AS THE
LOW CONTS E INTO THE OPEN N ATLC. WITH A MDTLY STRONG SFC PRES
GRAD AND WINDS IN THE 925 TO 850 MB LAYER ABOUT 25 KT XPCTD TO
CONT OVR THE REGION INTO AFTN...THE POTENTIAL OF BRISK GUSTY WINDS
TO 35 MPH AND EVEN 40+ MPH OVR HIER TRRN EXISTS LATER THIS MORN
INTO MID AFTN WHEN SFC-1000M LAPSE RATES BECOME STEEP. WIND GUSTS
OF 35+ MPH WILL STILL BE CAPABLE OF PRODUCING PATCHY BLSN OVR OPEN
TRRN AREAS...BUT ALL IN ALL CONDITIONS WILL STILL BE AN
IMPROVEMENT OVR YSTDY WHICH FEATURED MORE WIDESPREAD BLSN. HI
TEMPS THIS AFTN WILL CONT VERY COLD...BUT NOT QUITE AS COLD AS
YSTDY AFTN.
WITH BOTH THE SFC PRES GRAD AND WINDS ALF SLACKENING AFT SUNSET...
WINDS SHOULD DECREASE TO A LGT BREEZE OVR ERN PTNS OF THE FA...
AND EVEN DECOUPLE OVR BROAD WRN VLYS LATE TNGT AS THE AXIS OF THE
SFC HI APCHS THIS PTN OF THE REGION BY ERLY FRI MORN. THE
POTENTIAL OF SHALLOW SFC-BASE INVSN OVR THE BROAD WRN VLYS SHOULD
ALLOW FOR LOW TEMPS TO FALL BLO ZERO OVR THIS AREA...WITH SINGLE
DIGITS OVR THE REST OF THE N AND CNTRL AND ARND 10 ABV FOR
DOWNEAST AREAS BY ERLY FRI MORN.
FRI WILL BEGIN SUNNY...THEN CLDNSS FROM SFC LOWS AND ASSOCIATED
S/WVS FROM THE MID ATLC STATES AND CNTRL CAN BEGIN TO ARRIVE FRI
AFTN...SPCLY OVR WRN PTNS OF THE FA. WITH MUCH LIGHTER WINDS HI
TEMPS SHOULD CONT TO RECOVER ON FRI...REACHING THE LOWER TO MID
30S ACROSS ALL XCPT HIGHEST TRRN LCTNS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
PRECIPITATION CHANCES INCREASE FOR THE END OF THE WEEK AS AN
UPPER TROUGH APPROACHES FROM THE NORTHWEST. THE LATEST RUN OF THE
ECMWF HAS COME INTO LINE WITH THE REST OF THE GUIDANCE WITH THE
HANDLING OF THIS SYSTEM. MODEL CONSENSUS DEVELOPS A NORTHERN
STREAM SURFACE LOW WHICH WOULD TRACK ACROSS SOUTHERN
QUEBEC/NORTHERN MAINE, BRINGING ITS ATTENDANT COLD FRONT TO OUR
WESTERN AREAS BY SATURDAY EVENING. THIS SOLUTION ALSO DEVELOPS A
SOUTHERN LOW BUT KEEPS IT WELL SOUTH OF NOVA SCOTIA. THIS PATTERN
WOULD MEAN A MIX OF LIGHT RAIN AND SNOW FOR OUR FORECAST AREA
DURING THE DAY SATURDAY. HAVE GONE WITH A BLEND THAT LEANED
HEAVILY ON THE GFS AND ALSO INCLUDED THE PREVIOUS FORECAST TO
MAINTAIN SOME CONSISTENCY. THE MAIN CHANGE WAS TO INCREASE QPF A
BIT OVER NORTHERN AND WESTERN MAINE WHILE LOWERING IT DOWNEAST AND
OVER THE WATERS. TEMPERATURES WILL BE IN THE LOWER TO MID 30S ON
SATURDAY, SO EXPECT THAT DOWNEAST WILL CHANGE OVER TO RAIN FOR A
TIME DURING THE AFTERNOON. ELSEWHERE, RAIN WILL AT LEAST MIX WITH
SNOW, EXCEPT IN THE HIGHER TERRAIN IN THE NORTH WOODS. SNOW
ACCUMULATION WILL BE AROUND AN INCH AT MOST, THOUGH THE HIGHER
TERRAIN MAY SEE AROUND 2 INCHES BY SATURDAY EVENING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE AFOREMENTIONED COLD FRONT WILL CROSS THE STATE FROM WEST TO
EAST SATURDAY NIGHT. THIS WILL ALLOW PRECIPITATION TO TAPER OFF TO
SHOWERS WHILE CHANGING OVER TO ALL SNOW. A MUCH COLDER AIRMASS
WILL FOLLOW, WITH BRISK NORTHWEST WINDS AND WELL BELOW NORMAL
TEMPERATURES FOR SUNDAY THROUGH MONDAY. LINGERING SNOW SHOWERS
WILL BE POSSIBLE OVER FAR NORTHERN AREAS EARLY NEXT WEEK AS WELL.
WE`LL START TO SEE SOME IMPROVEMENT ON TUESDAY AS HIGH PRESSURE
CRESTS OVER THE REGION. THE HIGH WILL MOVE OFFSHORE ON WEDNESDAY,
PLACING NEW ENGLAND UNDER SOUTHWEST FLOW AND ALLOWING TEMPERATURES
TO FINALLY GET CLOSE TO NORMAL.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR XPCTD THRU FRI...WITH PERHAPS BRIEF INTERVALS OF
SC MVFR CLGS THIS MORN OVR NRN MOST TAF SITES...SPCLY KFVE.
SHORT TERM: VFR CONDITIONS FRIDAY NIGHT AND EARLY SATURDAY WILL
GIVE WAY TO MVFR/LOCAL IFR BY SATURDAY AFTERNOON AS LIGHT RAIN AND
SNOW CROSS THE REGION. THE NORTHERN TERMINALS, ESPECIALLY KFVE,
HAVE THE BEST CHANCES OF REMAINING ALL SNOW DURING THE DAY
SATURDAY. MVFR TO LINGER THROUGH AT LEAST 06Z SUNDAY, WITH IFR
POSSIBLE AT KFVE DUE TO SNOW SHOWERS COMING OFF THE SAINT
LAWRENCE. CONDITIONS WILL IMPROVE DURING THE DAY SUNDAY WITH ALL
SITES TO BE VFR BY 00Z MONDAY.
&&
.MARINE...
NEAR TERM: WILL CONT WITH THE GALE WRNG OVR OUR WATERS WITH LLVL
COLD ADVCN WNW WINDS...DUE TO EXPIRE AT NOON...AT WHICH POINT AN
INTERIM SCA WILL LIKELY BE NEEDED FOR THE REMAINDER OF THE AFTN
INTO ERLY EVE...SPCLY OVR THE OUTER MZS WATERS. THE FZGSPY ADV FOR
MDT FZSPY WOULD ALSO EXPIRE OVR OUR WATERS AT NOON...FOLLOWED BY
A PD OF LGT FZSPY ROUGHLY CORRESPONDING WITH SCA CONDITIONS.
AFTWRDS...WE ANTICIPATE NO HDLNS LATER TNGT CONTG THRU FRI.
INITIALLY ERLY THIS MORN...OBSVD WV HTS ARE RUNNING ABOUT 1 TO 2
FT ABV FCST WW3 WV GUIDANCE...THEN WE SLOWLY MERGE TO WW3 GUIDANCE
LATE TNGT INTO FRI.
SHORT TERM: GALE HEADLINES WILL LIKELY BE NEEDED ACROSS THE
WATERS FOR EARLY NEXT WEEK. A STRONG COLD FRONT WILL CROSS THE
WATERS LATE SATURDAY, WITH MUCH COLDER AIR SPREADING IN ITS WAKE.
THIS WILL RESULT IN GUSTY NORTHWEST WINDS OF 20 TO 25 KT, WITH
GUSTS OF 35-40 KT. SEAS WILL BE 5 TO 8 FEET. SMALL CRAFT
CONDITIONS WILL BE MET BY MIDNIGHT SUNDAY MORNING, WITH GALES TO
PREVAIL THROUGH THE DAY SUNDAY INTO SUNDAY EVENING. THERE WILL BE
SOME IMPROVEMENT MONDAY, THOUGH WINDS WILL LIKELY STAY ABOVE SMALL
CRAFT CRITERIA UNTIL MONDAY NIGHT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...FREEZING SPRAY ADVISORY UNTIL NOON EDT TODAY FOR ANZ050>052.
GALE WARNING UNTIL NOON EDT TODAY FOR ANZ050>052.
&&
$$
NEAR TERM...VJN
SHORT TERM...HASTINGS
LONG TERM...HASTINGS
AVIATION...VJN/HASTINGS
MARINE...VJN/HASTINGS
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
220 PM MST THU MAR 19 2015
.SYNOPSIS... CLOUDY CONDITIONS WITH AREAS OF LIGHT SHOWERS WILL
PERSIST TONIGHT. A DRYING AND WARMING TREND CAN BE EXPECTED
BEGINNING FRIDAY AND CONTINUING INTO THE MIDDLE PART OF NEXT WEEK.
&&
.DISCUSSION...PRECIPITATION FROM THIS MORNING HAS DISSIPATED WHILE
NEW CONVECTION HAS BLOSSOMED. FOCUS HAS SHIFTED FURTHER SOUTH
TOWARDS AN UNSTABLE AREA STRETCHING FROM EASTERN YUMA INTO PINAL
COUNTY. LATEST RAP MESOANALYSIS INDICATES SBCAPES AS HIGH AS 500
J/KG IN THIS REGION. ALTHOUGH THE LATEST RUNS OF THE HRRR HAVE
FAILED TO INITIALIZE THIS CONVECTION...CONDITIONS REMAIN FAVORABLE
FOR ADDITIONAL DEVELOPMENT THROUGH LATE AFTERNOON. MODEL CONSENSUS
ALSO INDICATES ANOTHER AREA FAVORABLE FOR PRECIPITATION IS ACROSS
EASTERN MARICOPA AND SOUTHERN GILA COUNTIES AND HIGHER POPS HAVE
BEEN RETAINED IN THESE AREAS THROUGH MIDNIGHT.
&&
.PREVIOUS DISCUSSION... LATEST RAP ANALYSIS SHOWS THE CENTER OF THE
MID-TROPOSPHERIC TROUGH NEAR PUERTO PENASCO. NUMEROUS SMALL VORTICES
ARE EMBEDDED IN THE TROUGH...WHICH HELPED TO ENHANCE ASCENT AND
SHOWER ACTIVITY OVERNIGHT. HIGHEST RAIN TOTALS HAVE BEEN OBSERVED
ACROSS NORTHERN MARICOPA COUNTY...GENERALLY BETWEEN A HALF OF AN
INCH AND THREE QUARTERS OF AN INCH...THOUGH ONLY 0.01 INCHES HAS
BEEN OBSERVED AT SKY HARBOR AIRPORT. KTWC MEASURED A PWAT OF 0.77
INCHES THIS MORNING...WHICH APPEARS TO BE A RECORD MAX FOR THE DATE.
THIS EQUATES TO STANDARDIZED ANOMALIES OF 2+ ACROSS MUCH OF AZ. AT
THE SURFACE...DEWPOINTS ARE ALSO WELL ABOVE AVERAGE...GENERALLY IN
THE MID 50S ACROSS THE AREA.
GLOBAL MODELS SUGGEST LARGER SCALE FORCING FOR ASCENT WILL BE WANING
TODAY AS MUCH OF THE AREA BECOMES POSITIONED BEHIND THE EASTWARD-
ADVANCING TROUGH AXIS. HOWEVER...HI-RES GUIDANCE INCLUDING THE HRRR
SUGGEST THE AFOREMENTIONED VORTICES WILL SUPPORT ADDITIONAL SHOWER
ACTIVITY THROUGH THIS AFTERNOON...MAINLY ACROSS NORTHERN AND WESTERN
MARICOPA COUNTY. POPS WERE INCREASED IN THESE AREAS AND TEMPERATURES
WERE ALSO LOWERED A FEW DEGREES. LATEST VISIBLE SATELLITE ALSO SHOWS
SOME AREAS OF CLEARING...MAINLY ACROSS PINAL COUNTY THIS MORNING.
INSTABILITY WILL INCREASE THIS AFTERNOON ACROSS PORTIONS OF THE AREA
AND CONVECTIVE PARAMETERS ALSO SUGGEST THE POTENTIAL FOR AN ISOLATED
RUMBLE OF THUNDER.
A DRYING TREND IS THEN EXPECTED TO BEGIN TO WORK ITS WAY EASTWARD
ACROSS THE REGION THIS EVENING AS THE MAIN TROF AXIS SHIFTS SLOWLY
OFF TO THE EAST AND PWATS BEGIN TO DROP...WITH MOST OF THE SHOWER
ACTIVITY SHIFTING INTO SOUTHERN GILA COUNTY BY LATE TONIGHT. FRIDAY
WILL SEE MORE ISOLATED-SCATTERED SHOWER ACTIVITY ACROSS SOUTHERN
GILA COUNTY AS A BIT OF MOISTURE IS WRAPPED BACK WESTWARD INTO THAT
REGION. THE CLOUDS AND SHOWERS WILL HOLD TEMPERATURES WELL INTO THE
70S ACROSS THE LOWER DESERTS OF SOUTH-CENTRAL ARIZONA...WITH SOME
LOW 80S ACROSS SW AZ AND SE CA...WITH SOME MODEST WARMING ON FRIDAY
AS SKIES BEGIN TO CLEAR.
SATURDAY THROUGH THURSDAY...A WARMING AND DRYING TREND STILL APPEARS
ON TAP FROM SATURDAY ONWARD INTO AT LEAST THE MIDDLE OF NEXT WEEK AS
BOTH THE GFS AND EURO MODELS CONTINUE TO BUILD FLAT RIDGING BACK
OVER THE REGION AS THE AFOREMENTIONED UPPER TROF MOVES OFF WELL TO
OUR EAST...WITH LOWER DESERT HIGHS LIKELY REACHING 90 DEGREES BY
EARLY NEXT WEEK. SOME COOLING IS POSSIBLE BY THE END OF NEXT WEEK AS
THE NEXT MAJOR LOW-WAVE TROF BRUSHES BY WELL TO OUR NORTH AND EAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
THICK ISOLD TO WIDELY SCT SHOWERS WITH MID-LEVEL CIGS AS LOW AS 6 TO
8KFT WILL PREVAIL THROUGH THE AFTERNOON. WINDS GENERALLY LIGHT
THROUGH 12Z FRIDAY MORNING...BUT STILL AN OUTSIDE CHANCE OF A
THUNDERSTORM AND GUSTY WINDS THIS AFTERNOON...HOWEVER CONFIDENCE TOO
LOW AND THE COVERAGE TOO ISOLATED TO MENTION IN TAFS. STORM ACTIVITY
EXPECTED TO DWINDLE AFTER 02Z...AND SKIES BEGIN TO CLEAR OUT LATER
THIS EVENING AS UPPER LEVEL LOW MOVES SLOWLY EAST OVERNIGHT.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SCT-BKN MID-HIGH LEVEL CLOUD DECKS WILL BEGIN TO THIN OUT LATER THIS
AFTERNOON/EVENING...WITH AN ISOLATED SHOWER LINGERING OVER THE AREA
UNTIL 01Z FRIDAY. WINDS WILL STAY RATHER LIGHT/VARIABLE OVER THE
AREA THROUGH FRIDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY... AN AREA OF LOW PRESSURE
WILL EXIT TO THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO
FILTER INTO THE LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE
TEENS ACROSS THE CENTRAL AND WESTERN DESERTS. THERE WILL BE A
LINGERING SLIGHT CHANCE OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF
PHOENIX...MAINLY TO THE EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A
DRY WESTERLY FLOW ALOFT WILL DOMINATE THE WEATHER PATTERN AS HIGHER
PRESSURE ALOFT SLOWLY BUILDS ACROSS THE REGION. HIGH TEMPERATURES
WILL STEADILY CLIMB WITH THE WARMER LOWER DESERTS REACHING THE UPPER
80S TO LOW 90S BY MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS
EXPECTED OVER THE NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH
DESERTS READINGS BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST
HALF OF NEXT WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY
THROUGH MONDAY WITH WINDS INCREASING TUESDAY AND
WEDNESDAY...BECOMING BREEZY FROM THE WEST DURING THE AFTERNOON HOURS
EACH DAY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...HIRSCH/PERCHA
AVIATION...MEYERS
FIRE WEATHER...CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
935 AM MST THU MAR 19 2015
.SYNOPSIS...
CLOUDY CONDITIONS AND COOLER TEMPERATURES WILL BE IN OUR AREA
THROUGH TODAY. SOME LIGHT SHOWERS WITH EVEN A RUMBLE OF THUNDER MAY
BE SEEN. A DRYING...AND WARMING TREND WILL BE SEEN BEGINNING FRIDAY
AND CONTINUING INTO THE MIDDLE PART OF NEXT WEEK.
&&
.DISCUSSION... LATEST RAP ANALYSIS SHOWS THE CENTER OF THE MID-
TROPOSPHERIC TROUGH NEAR PUERTO PENASCO. NUMEROUS SMALL VORTICES ARE
EMBEDDED IN THE TROUGH...WHICH HELPED TO ENHANCE ASCENT AND SHOWER
ACTIVITY OVERNIGHT. HIGHEST RAIN TOTALS HAVE BEEN OBSERVED ACROSS
NORTHERN MARICOPA COUNTY...GENERALLY BETWEEN A HALF OF AN INCH AND
THREE QUARTERS OF AN INCH...THOUGH ONLY 0.01 INCHES HAS BEEN
OBSERVED AT SKY HARBOR AIRPORT. KTWC MEASURED A PWAT OF 0.77 INCHES
THIS MORNING...WHICH APPEARS TO BE A RECORD MAX FOR THE DATE. THIS
EQUATES TO STANDARDIZED ANOMALIES OF 2+ ACROSS MUCH OF AZ. AT THE
SURFACE...DEWPOINTS ARE ALSO WELL ABOVE AVERAGE...GENERALLY IN THE
MID 50S ACROSS THE AREA.
GLOBAL MODELS SUGGEST LARGER SCALE FORCING FOR ASCENT WILL BE WANING
TODAY AS MUCH OF THE AREA BECOMES POSITIONED BEHIND THE EASTWARD-
ADVANCING TROUGH AXIS. HOWEVER...HI-RES GUIDANCE INCLUDING THE HRRR
SUGGEST THE AFOREMENTIONED VORTICES WILL SUPPORT ADDITIONAL SHOWER
ACTIVITY THROUGH THIS AFTERNOON...MAINLY ACROSS NORTHERN AND WESTERN
MARICOPA COUNTY. POPS WERE INCREASED IN THESE AREAS AND TEMPERATURES
WERE ALSO LOWERED A FEW DEGREES. LATEST VISIBLE SATELLITE ALSO SHOWS
SOME AREAS OF CLEARING...MAINLY ACROSS PINAL COUNTY THIS MORNING.
INSTABILITY WILL INCREASE THIS AFTERNOON ACROSS PORTIONS OF THE AREA
AND CONVECTIVE PARAMETERS ALSO SUGGEST THE POTENTIAL FOR AN ISOLATED
RUMBLE OF THUNDER.
&&
.PREVIOUS DISCUSSION... A DRYING TREND IS THEN EXPECTED TO BEGIN TO
WORK ITS WAY EASTWARD ACROSS THE REGION THIS EVENING AS THE MAIN
TROF AXIS SHIFTS SLOWLY OFF TO THE EAST AND PWATS BEGIN TO
DROP...WITH MOST OF THE SHOWER ACTIVITY SHIFTING INTO SOUTHERN GILA
COUNTY BY LATE TONIGHT. FRIDAY WILL SEE MORE ISOLATED-SCATTERED
SHOWER ACTIVITY ACROSS SOUTHERN GILA COUNTY AS A BIT OF MOISTURE IS
WRAPPED BACK WESTWARD INTO THAT REGION. THE CLOUDS AND SHOWERS WILL
HOLD TEMPERATURES WELL INTO THE 70S ACROSS THE LOWER DESERTS OF
SOUTH-CENTRAL ARIZONA...WITH SOME LOW 80S ACROSS SW AZ AND SE
CA...WITH SOME MODEST WARMING ON FRIDAY AS SKIES BEGIN TO CLEAR
SATURDAY THROUGH THURSDAY...A WARMING AND DRYING TREND STILL APPEARS
ON TAP FROM SATURDAY ONWARD INTO AT LEAST THE MIDDLE OF NEXT WEEK AS
BOTH THE GFS AND EURO MODELS CONTINUE TO BUILD FLAT RIDGING BACK
OVER THE REGION AS THE AFOREMENTIONED UPPER TROF MOVES OFF WELL TO
OUR EAST...WITH LOWER DESERT HIGHS LIKELY REACHING 90 DEGREES BY
EARLY NEXT WEEK. SOME COOLING IS POSSIBLE BY THE END OF NEXT WEEK AS
THE NEXT MAJOR LOW-WAVE TROF BRUSHES BY WELL TO OUR NORTH AND EAST.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
THICK MIDLEVEL CIGS WILL PREVAIL THROUGH THIS AFTERNOON...
POTENTIALLY BRIEFLY TOUCHING AS LOW AS 6K-8K FT LATE THIS MORNING
AND INTO THE EARLY AFTERNOON. VERY LIGHT SHOWERS/SPRINKLES WILL
CONTINUE INTO THE AFTERNOON...HOWEVER SHOULD NOT AMOUNT TO MUCH MORE
THAN A TRACE AND PROVIDE MINIMAL IMPACT. ONLY MODERATE CONFIDENCE IN
ANY WIND SHIFTS THROUGH THE EARLY AFTERNOON...THOUGH DIRECTIONS
SHOULD FAVOR AN EASTERLY COMPONENT. WINDS SHOULD RETURN TO THE WEST
BY MID TO LATE AFTERNOON. THERE IS AN OUTSIDE CHANCE OF A
THUNDERSTORM DURING THE AFTERNOON BUT CONFIDENCE TOO LOW...AND
COVERAGE TOO ISOLATED...TO MENTION THUNDER IN THE UPCOMING MORNING
TAF PACKAGE. OF COURSE SHOULD A STORM DEVELOP THE WINDS WILL BECOME
SQUIRRELY AND UNCERTAIN...AND LOCALLY GUSTY.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
EXTENSIVE THICK CIGS IN AN 8K-12K FT RANGE WILL ONLY BEGIN TO
SCATTER BY THIS AFTERNOON. THERE MAY BE A FEW SHOWERS AT THE TAF
SITES THROUGH LATE MORNING...BUT THREATS FOR PRECIP SHOULD BE MOSTLY
OVER AFTER 19Z. WINDS WILL STAY RATHER LIGHT/VARIABLE AT BOTH SITES
TODAY BUT WILL LIKELY FAVOR THE SOUTH AT KBLH.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY... AN AREA OF LOW PRESSURE WILL EXIT TO
THE EAST SATURDAY ALLOWING A DRIER WESTERLY FLOW TO FILTER INTO THE
LOWER DESERTS...LOWERING HUMIDITY VALUES INTO THE TEENS ACROSS THE
CENTRAL AND WESTERN DESERTS. THERE WILL BE A LINGERING SLIGHT CHANCE
OF SHOWERS ACROSS THE HIGHER TERRAIN EAST OF PHOENIX...MAINLY TO THE
EAST OF GLOBE. FOR SUNDAY INTO WEDNESDAY...A DRY WESTERLY FLOW ALOFT
WILL DOMINATE THE WEATHER PATTERN AS HIGHER PRESSURE ALOFT SLOWLY
BUILDS ACROSS THE REGION. HIGH TEMPERATURES WILL STEADILY CLIMB WITH
THE WARMER LOWER DESERTS REACHING THE UPPER 80S TO LOW 90S BY
MONDAY...THEN LITTLE CHANGE IN TEMPERATURES IS EXPECTED OVER THE
NEXT 2 DAYS. MINIMUM RH VALUES WILL FALL OFF WITH DESERTS READINGS
BETWEEN 10 AND 15 PERCENT EXPECTED DURING THE FIRST HALF OF NEXT
WEEK. RATHER LIGHT WEST WIND IS EXPECTED SATURDAY THROUGH MONDAY
WITH WINDS INCREASING TUESDAY AND WEDNESDAY...BECOMING BREEZY FROM
THE WEST DURING THE AFTERNOON HOURS EACH DAY.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...MO/CB
FIRE WEATHER...CB
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
127 PM PDT THU MAR 19 2015
.SYNOPSIS...
AN UPPER LEVEL LOW PRESSURE SYSTEM OVER NORTHERN BAJA MAY BRING A
FEW ADDITIONAL SHOWERS AND THUNDERSTORMS THIS AFTERNOON INTO EARLY
EVENING...MAINLY FOR THE INLAND VALLEYS AND MOUNTAINS OF SAN DIEGO
COUNTY. HIGHER PRESSURE ALOFT WILL BRING DRY...WARMER WEATHER FRIDAY
THROUGH MONDAY...WITH DAY-TIME HIGHS SEVERAL DEGREES ABOVE NORMAL.
NIGHT AND MORNING MARINE LAYER STRATUS WILL CONTINUE OVER THE COAST
AND PORTIONS OF THE VALLEYS. SOME OFFSHORE FLOW AND MORE WARMING IS
POSSIBLE BY MID NEXT WEEK.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING
ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN
BERNARDINO COUNTIES...
AN UPPER LEVEL LOW...CURRENTLY SOUTH OF THE BORDER ACCORDING TO
WATER VAPOR SATELLITE...WILL CONTINUE TO MOVE TO THE SOUTH AND EAST
THROUGH FRIDAY. BEFORE IT LEAVES...SOME LINGERING MOISTURE AND
INSTABILITY COULD BRING ANOTHER ROUND OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS TODAY. RADAR DOES NOT SHOW MUCH OVER OUR AREA
AT THE MOMENT...WITH THE NEAREST SHOWERS SOUTH OF THE BORDER AND
OVER IMPERIAL COUNTY. THE SHOWERS ARE MOVING TO THE SOUTHWEST DUE TO
THE NORTHEAST FLOW ALOFT. CURRENT GPS PRECIPITABLE WATER SENSORS
OVER THE REGION CONTINUE TO INDICATE ABOUT 0.8 TO 0.9 INCHES OF
PRECIPITABLE WATER...WHICH IS ENOUGH MOISTURE FOR
PRECIPITATION...AND THE LATEST SPC MESOANALYSIS INDICATES 500 J/KG
OF MOST UNSTABLE CAPE OVER THE AREA. ALSO...THE HRRR CONTINUES TO
SHOW THE SAN DIEGO COUNTY VALLEYS GETTING SOME HEAVY SHOWERS AND
THUNDERSTORMS FOR A FEW HOURS DURING THE MID TO LATE AFTERNOON HOURS
TODAY DUE TO DAY-TIME SURFACE HEATING AND A POSSIBLE UPPER WAVE
MOVING THROUGH. THUS...THE POTENTIAL REMAINS FOR SOME HEAVY SHOWERS
AND THUNDERSTORMS DEVELOPING THIS AFTERNOON INTO EARLY
EVENING...WITH SAN DIEGO COUNTY LOOKING LIKE THE AREA WITH THE
BIGGEST THREAT.
TONIGHT INTO FRIDAY...AS THE LOW MOVES FARTHER FROM THE AREA TO THE
SOUTHEAST MUCH DRIER AIR MOVES IN OVER THE AREA BRINGING AN END TO
THE SHOWER/THUNDERSTORMS. THE MARINE LAYER SHOULD REMAIN
ESTABLISHED...WITH STRATUS LIKELY MOVING INTO THE COAST AND VALLEYS
AGAIN. TEMPERATURE LOOK TO BE SEVERAL DEGREES HIGHER ON FRIDAY DUE
TO CLEARING SKIES AND A RIDGE WHICH STARTS TO BUILD OVER THE AREA.
WEATHER CONDITIONS WILL BE SIMILAR SATURDAY THROUGH MONDAY WITH WEAK
RIDGING ALOFT...ONSHORE FLOW AT THE SURFACE...NIGHT AND MORNING
MARINE LAYER STRATUS MOVING INTO THE COAST AND WESTERN VALLEY
AREAS...AND TEMPERATURES SEVERAL DEGREES ABOVE NORMAL. A TROUGH
MOVING INTO THE PACIFIC NORTHWEST LATE MONDAY INTO EARLY TUESDAY
LOOKS TO BRING SOME STRONGER ONSHORE FLOW...AND SOME GUSTY WEST
WINDS TO THE MOUNTAINS AND DESERTS.
SLIGHTLY COOLER CONDITIONS WILL PREVAIL TUESDAY WITH WEAK OFFSHORE
FLOW STARTING TO DEVELOP. WEDNESDAY INTO THURSDAY...A WEAK AND DRY
TROUGH WILL MOVE OVER SOUTHERN CALIFORNIA...AND THERE IS THE
POTENTIAL FOR SOME MODERATE OFFSHORE FLOW AND INCREASED WARMING.
THIS WOULD ERADICATE THE MARINE LAYER.
&&
.AVIATION...
192000...VFR CONDITIONS FORECAST FOR MOST AREAS THROUGH LATE THIS
AFTERNOON. -SHRA/-TSRA WILL BE POSSIBLE THROUGH EARLY THIS
EVENING...MAINLY OVER INLAND AREAS. SMALL HAIL...REDUCED VIS FROM
RAIN...FREQUENT LIGHTNING AND STRONG UP/DOWN DRAFTS WILL BE POSSIBLE
NEAR STORMS. MARINE LAYER STRATUS...WITH BASES NEAR 1500 FT MSL AND
TOPS TO 2500 FT MSL...WILL REDEVELOP ALONG THE COAST THIS EVENING
AND PUSH AROUND 15-30 SM INLAND BY EARLY FRIDAY MORNING. VIS OF 3-5
SM BR WILL BE POSSIBLE WHERE STRATUS NEARS HIGHER TERRAIN. LOW
CLOUDS WILL CLEAR TOWARDS THE COAST BY LATE FRIDAY MORNING.
&&
.MARINE...
100 PM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH SUNDAY.
BREEZY NORTHWEST WINDS WILL DEVELOP LATE MONDAY OVER THE OUTER
COASTAL WATERS...WITH GUSTS TO 20-25 KT POSSIBLE.
&&
.SKYWARN...
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...HARRISON
AVIATION/MARINE...JJT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1209 PM MDT THU MAR 19 2015
.UPDATE...
ISSUED AT 1206 PM MDT THU MAR 19 2015
BACK EDGE OF HEAVIER/STEADIER PRECIP DROPPING SLOWLY SOUTH THROUGH
THE AREA...AND HAVE BEGUN TO TAPER OFF POPS FROM NORTH TO SOUTH
ACCORDINGLY. HAVE KEPT CURRENT SET OF WINTER HIGHLIGHTS
INTACT...WILL LIKELY END CENTRAL MOUNTAINS/TELLER COUNTY EARLY
WITH NEXT FORECAST UPDATE LATER THIS AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM MDT THU MAR 19 2015
...RAIN AND MTN SNOW TO CONTINUE TODAY BEFORE WINDING DOWN LATER
TONIGHT...
UPPER TROF AXIS CURRENTLY EXTENDS FROM ND...SOUTHWESTWARD ACROSS WY
AND UT...WITH BROAD CLOSED LOW CENTERED ACROSS THE NRN BAJA
PENINSULA. RADAR ECHOES HAVE BLOSSOMED OVER THE SOUTHEAST
MTS/ADJACENT PLAINS EARLY THIS MORNING AS VORT MAX WHICH EJECTED OUT
OF THE DESERT SOUTHWEST LIFTS TO THE NORTHEAST. HRRR SEEMS TO HAVE
A FAIRLY GOOD HANDLE ON THE TIMING OF THE PRECIP...WHICH LIFTS OFF
TO THE NORTHEAST THIS MORNING...WHILE FILLING IN ACROSS EL PASO
COUNTY...THEN SPREADING BACK SOUTHWARD DURING THE MORNING HOURS AS
THE FRONT DROPS SOUTHWARD...AND FORCING FROM THE UPPER TROF AXIS
MOVES IN. THUS...EXPECT WIDESPREAD RAIN AND MOUNTAIN SNOWS TO FILL
IN ALONG THE SOUTHERN I-25 CORRIDOR THROUGH 15Z...AND CONTINUE INTO
THE EARLY AFTERNOON WITH FOCUS SHIFTING INTO THE SOUTHWEST MTS
DURING THE AFTERNOON AS INSTABILITY FROM THE TROF AXIS ACTS ON
FAIRLY GOOD FETCH OF MOISTURE FROM THE SOUTH. SUSPECT THAT
ADVISORIES ACROSS NORTHEAST PORTIONS OF THE AREA (TELLER/NRN
FREMONT) MAY BE ABLE TO BE TAKEN DOWN BY 00Z AS HRRR AND RAP SHOW
PRECIPITATION DWINDLING QUICKLY DURING THE LATE AFTERNOON HOURS.
SOUTHERN AND CENTRAL MOUNTAIN AREAS WILL CONTINUE TO SEE SNOW INTO
THE EVENING HOURS AS DEEP EASTERLY UPSLOPE FLOW CONTINUES. SNOW
LEVELS ARE PROBABLY AROUND 7500 FEET AS OF 4 AM THIS MORNING...BASED
ON WEB CAMS AROUND THE PIKES PEAK REGION. SNOW LEVELS MAY BRIEFLY
DROP TO AROUND 6500 FEET THIS MORNING...BUT BY IN LARGE WILL
PROBABLY HOVER AROUND 7000-7500 FEET THROUGH MOST OF THE DAY. SNOW
AMOUNTS WILL BE HIGHLY DEPENDENT ON GETTING THE SNOW LEVELS CORRECT.
AND ANYTIME YOU ADD THE CONVECTIVE ELEMENT...THIS CAN LEAD TO
INTENSE SNOWFALL RATES WITH QUICK ACCUMULATIONS OF HEAVY WET SNOW.
MODELS STILL LOOK OVERDONE WITH THE AREAL COVERAGE OF THESE HEAVIER
SNOWFALL AMOUNTS...BUT MAGNITUDE IS CERTAINLY POSSIBLE WITH SNOWFALL
RATES OF OVER AN INCH AN HOUR POSSIBLE AT TIMES. CURRENT SUITE OF
HIGHLIGHTS STILL LOOKS ON TRACK. SOME CONCERN AREAS FOR TODAY WILL
BE THE LOWER ELEVATIONS OF TELLER COUNTY AND THE WET MOUNTAINS...AS
NORTHEAST FACING SLOPES COULD PICK UP CLOSE TO A FOOT IF SNOW LEVELS
STAY LOW ENOUGH FOR LONG ENOUGH. HOWEVER...AREAL COVERAGE OF THESE
HIGHER AMOUNTS DO NOT APPEAR TO JUSTIFY UPGRADING TO WARNINGS AT
THIS POINT. HOWEVER...HEAVY WET SPRING LIKE SNOWS OFTEN LEAD TO
HIGHLY CHANGEABLE FORECASTS...SO THIS WILL CONTINUE TO BE MONITORED.
MEANWHILE...RAINFALL ON THE LOWER SLOPES OF THE WALDO SHOULD SWITCH
OVER TO SNOW IN THE NEXT HOUR OR TWO. RAINFALL RATES HAVE REMAINED
UNDER .15 PER HOUR...AND DO NOT EXPECT THEM TO EXCEED THIS
RATE...EVEN IF SNOW SWITCHES BACK TO RAIN LATER THIS MORNING...SO
NOT EXPECTING A FLASH FLOOD THREAT FOR WALDO. THAT SAID...SOME
CREEKS AND DRAINAGES MAY EXPERIENCE SOME MINOR RUNOFF THROUGH THE
DAY.
SOUTHWEST MOUNTAINS AND CENTRAL MOUNTAINS SHOULD SEE AROUND 4-8
INCHES OF SNOW THIS AFTERNOON AND EVENING AS TROF AXIS MOVES ACROSS.
INSTABILITY MAY BE SUFFICIENT FOR AN ISOLATED EMBEDDED THUNDERSTORM
ACROSS THE SOUTHWEST MOUNTAINS THIS AFTERNOON AS WELL...WHICH COULD
BRING SOME LOCALLY HEAVY SNOWFALL AT TIMES. IN ADDITION...EASTERLY
UPSLOPE FLOW MAY ALSO SERVE TO FOCUS PRECIPITATION ALONG THE EASTERN
SLOPES OF THE EASTERN SAN JUANS. HOWEVER...SNOW LEVELS LOOK EVEN
HIGHER OUT THAT WAY...AROUND 8KFT...SO HEAVIER ACCUMULATIONS SHOULD
BE CONFINED TO THE HIGHER ELEVATIONS. AGAIN...CURRENT ADVISORIES
STILL LOOK ON TARGET. PRECIPITATION WILL TAIL OFF FROM NORTH TO
SOUTH OVERNIGHT. -KT
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 428 AM MDT THU MAR 19 2015
FRIDAY...THE UPPER LOW OVER AZ AND OLD MEXICO IS FORECAST TO WEAKEN
AND GRADUALLY SLIDE TO THE EAST ON FRIDAY...ALLOWING PRECIPITATION
TO DIMINISH FROM NORTH TO SOUTH FRIDAY MORNING. SHOWER ACTIVITY WILL
LINGER THE LONGEST OVER THE SW MTS AND SOUTHERN SANGRES. LOOK FOR
TEMPS TO REBOUND BACK INTO THE 50S TO MID 60S ACROSS MUCH OF THE
AREA.
SATURDAY THROUGH MONDAY...LONGER RANGE MODELS AGREE ON KEEPING A
GENERAL WESTERLY FLOW ALOFT ACROSS THE STATE OVER THE WEEKEND AND
INTO THE NEXT WORK WEEK. A COUPLE OF DISTURBANCES PASSING TO THE
NORTH WILL BRING THE THREAT OF SHOWERS TO THE HIGHER TERRAIN...BUT
MODELS ARE NOT ON THE SAME PAGE FOR TIMING OF THESE.
THEREFORE...DECIDED TO LEAN TOWARDS THE GFS AT THIS TIME WHICH
INDICATES ISOLATED SHOWERS FOR THE S MTS ON SAT...A STRONGER
DISTURBANCE AFFECTING MAINLY THE CENTRAL MTS AND RAMPART RANGE ON
SUNDAY...THEN A DRY MONDAY. LOOK FOR WARMER TEMPS ALL THREE
DAYS...WITH 70S ACROSS THE E PLAINS AND 60S FOR THE HIGH VALLEYS.
TUESDAY AND WEDNESDAY...MODELS ARE TRENDING TOWARDS A MUCH STRONGER
UPPER TROUGH DROPPING OUT OF CANADA ON TUESDAY...BRINGING PCPN BACK
TO THE FORECAST AREA TUES NIGHT THROUGH WEDNESDAY. INCREASED WINDS
AND WAA TUE WOULD MEAN A VERY WARM DAY WITH MAX TEMPS PUSHING 80F ON
THE PLAINS...THEN ABOUT A 10-15 DEGREE COOLDOWN FOR WED. EC AND GFS
MODELS HINT AT THIS SOLUTION...BUT HAVE DIFFERING TIMING AND SYSTEM
STRENGTH SO FORECAST CONFIDENCE IS LOW AT THIS TIME. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1102 AM MDT THU MAR 19 2015
BACK EDGE OF STEADIER/HEAVIER PRECIP ALREADY THROUGH KCOS AS OF
17Z...AND WILL LIKELY MOVE THROUGH KPUB AROUND 19Z. A FEW SHOWERS
WILL STILL LINGER BOTH SITES FOR THE REMAINDER OF THE
AFTERNOON...THOUGH CONDITIONS WILL BE PREDOMINATELY VFR WITH ONLY
SOME BRIEF MVFR UNDER HEAVIER SHOWERS. AT KALS...LOWER CLOUDS AND
A FEW SHOWERS WILL PERSIST INTO THE AFTERNOON...WITH PERIODS OF
MVFR UNTIL 01Z. ALL TERMINALS WILL BECOME VFR THIS EVENING AS
SKIES GRADUALLY CLEAR BEHIND DEPARTING WEATHER SYSTEM...WITH VFR
CONDITIONS OVERNIGHT INTO FRIDAY MORNING.
OVER THE MOUNTAINS...MOST HIGHER TERRAIN WILL REMAIN OBSCURRED BY
-SHRA/-SHSN THROUGH THE AFTERNOON...BEFORE IMPROVING CONDITIONS
WORK FROM NORTH TO SOUTH ACROSS THE AREA EARLY THIS EVENING. BY
06Z...VFR MOST LOCATIONS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ082.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT FRIDAY FOR COZ066-068-072-
074-079.
WINTER STORM WARNING UNTIL 6 AM MDT FRIDAY FOR COZ073-075-080.
WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ058-
060-076-081.
&&
$$
UPDATE...PETERSEN
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1109 AM MDT THU MAR 19 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 428 AM MDT THU MAR 19 2015
...RAIN AND MTN SNOW TO CONTINUE TODAY BEFORE WINDING DOWN LATER
TONIGHT...
UPPER TROF AXIS CURRENTLY EXTENDS FROM ND...SOUTHWESTWARD ACROSS WY
AND UT...WITH BROAD CLOSED LOW CENTERED ACROSS THE NRN BAJA
PENINSULA. RADAR ECHOES HAVE BLOSSOMED OVER THE SOUTHEAST
MTS/ADJACENT PLAINS EARLY THIS MORNING AS VORT MAX WHICH EJECTED OUT
OF THE DESERT SOUTHWEST LIFTS TO THE NORTHEAST. HRRR SEEMS TO HAVE
A FAIRLY GOOD HANDLE ON THE TIMING OF THE PRECIP...WHICH LIFTS OFF
TO THE NORTHEAST THIS MORNING...WHILE FILLING IN ACROSS EL PASO
COUNTY...THEN SPREADING BACK SOUTHWARD DURING THE MORNING HOURS AS
THE FRONT DROPS SOUTHWARD...AND FORCING FROM THE UPPER TROF AXIS
MOVES IN. THUS...EXPECT WIDESPREAD RAIN AND MOUNTAIN SNOWS TO FILL
IN ALONG THE SOUTHERN I-25 CORRIDOR THROUGH 15Z...AND CONTINUE INTO
THE EARLY AFTERNOON WITH FOCUS SHIFTING INTO THE SOUTHWEST MTS
DURING THE AFTERNOON AS INSTABILITY FROM THE TROF AXIS ACTS ON
FAIRLY GOOD FETCH OF MOISTURE FROM THE SOUTH. SUSPECT THAT
ADVISORIES ACROSS NORTHEAST PORTIONS OF THE AREA (TELLER/NRN
FREMONT) MAY BE ABLE TO BE TAKEN DOWN BY 00Z AS HRRR AND RAP SHOW
PRECIPITATION DWINDLING QUICKLY DURING THE LATE AFTERNOON HOURS.
SOUTHERN AND CENTRAL MOUNTAIN AREAS WILL CONTINUE TO SEE SNOW INTO
THE EVENING HOURS AS DEEP EASTERLY UPSLOPE FLOW CONTINUES. SNOW
LEVELS ARE PROBABLY AROUND 7500 FEET AS OF 4 AM THIS MORNING...BASED
ON WEB CAMS AROUND THE PIKES PEAK REGION. SNOW LEVELS MAY BRIEFLY
DROP TO AROUND 6500 FEET THIS MORNING...BUT BY IN LARGE WILL
PROBABLY HOVER AROUND 7000-7500 FEET THROUGH MOST OF THE DAY. SNOW
AMOUNTS WILL BE HIGHLY DEPENDENT ON GETTING THE SNOW LEVELS CORRECT.
AND ANYTIME YOU ADD THE CONVECTIVE ELEMENT...THIS CAN LEAD TO
INTENSE SNOWFALL RATES WITH QUICK ACCUMULATIONS OF HEAVY WET SNOW.
MODELS STILL LOOK OVERDONE WITH THE AREAL COVERAGE OF THESE HEAVIER
SNOWFALL AMOUNTS...BUT MAGNITUDE IS CERTAINLY POSSIBLE WITH SNOWFALL
RATES OF OVER AN INCH AN HOUR POSSIBLE AT TIMES. CURRENT SUITE OF
HIGHLIGHTS STILL LOOKS ON TRACK. SOME CONCERN AREAS FOR TODAY WILL
BE THE LOWER ELEVATIONS OF TELLER COUNTY AND THE WET MOUNTAINS...AS
NORTHEAST FACING SLOPES COULD PICK UP CLOSE TO A FOOT IF SNOW LEVELS
STAY LOW ENOUGH FOR LONG ENOUGH. HOWEVER...AREAL COVERAGE OF THESE
HIGHER AMOUNTS DO NOT APPEAR TO JUSTIFY UPGRADING TO WARNINGS AT
THIS POINT. HOWEVER...HEAVY WET SPRING LIKE SNOWS OFTEN LEAD TO
HIGHLY CHANGEABLE FORECASTS...SO THIS WILL CONTINUE TO BE MONITORED.
MEANWHILE...RAINFALL ON THE LOWER SLOPES OF THE WALDO SHOULD SWITCH
OVER TO SNOW IN THE NEXT HOUR OR TWO. RAINFALL RATES HAVE REMAINED
UNDER .15 PER HOUR...AND DO NOT EXPECT THEM TO EXCEED THIS
RATE...EVEN IF SNOW SWITCHES BACK TO RAIN LATER THIS MORNING...SO
NOT EXPECTING A FLASH FLOOD THREAT FOR WALDO. THAT SAID...SOME
CREEKS AND DRAINAGES MAY EXPERIENCE SOME MINOR RUNOFF THROUGH THE
DAY.
SOUTHWEST MOUNTAINS AND CENTRAL MOUNTAINS SHOULD SEE AROUND 4-8
INCHES OF SNOW THIS AFTERNOON AND EVENING AS TROF AXIS MOVES ACROSS.
INSTABILITY MAY BE SUFFICIENT FOR AN ISOLATED EMBEDDED THUNDERSTORM
ACROSS THE SOUTHWEST MOUNTAINS THIS AFTERNOON AS WELL...WHICH COULD
BRING SOME LOCALLY HEAVY SNOWFALL AT TIMES. IN ADDITION...EASTERLY
UPSLOPE FLOW MAY ALSO SERVE TO FOCUS PRECIPITATION ALONG THE EASTERN
SLOPES OF THE EASTERN SAN JUANS. HOWEVER...SNOW LEVELS LOOK EVEN
HIGHER OUT THAT WAY...AROUND 8KFT...SO HEAVIER ACCUMULATIONS SHOULD
BE CONFINED TO THE HIGHER ELEVATIONS. AGAIN...CURRENT ADVISORIES
STILL LOOK ON TARGET. PRECIPITATION WILL TAIL OFF FROM NORTH TO
SOUTH OVERNIGHT. -KT
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 428 AM MDT THU MAR 19 2015
FRIDAY...THE UPPER LOW OVER AZ AND OLD MEXICO IS FORECAST TO WEAKEN
AND GRADUALLY SLIDE TO THE EAST ON FRIDAY...ALLOWING PRECIPITATION
TO DIMINISH FROM NORTH TO SOUTH FRIDAY MORNING. SHOWER ACTIVITY WILL
LINGER THE LONGEST OVER THE SW MTS AND SOUTHERN SANGRES. LOOK FOR
TEMPS TO REBOUND BACK INTO THE 50S TO MID 60S ACROSS MUCH OF THE
AREA.
SATURDAY THROUGH MONDAY...LONGER RANGE MODELS AGREE ON KEEPING A
GENERAL WESTERLY FLOW ALOFT ACROSS THE STATE OVER THE WEEKEND AND
INTO THE NEXT WORK WEEK. A COUPLE OF DISTURBANCES PASSING TO THE
NORTH WILL BRING THE THREAT OF SHOWERS TO THE HIGHER TERRAIN...BUT
MODELS ARE NOT ON THE SAME PAGE FOR TIMING OF THESE.
THEREFORE...DECIDED TO LEAN TOWARDS THE GFS AT THIS TIME WHICH
INDICATES ISOLATED SHOWERS FOR THE S MTS ON SAT...A STRONGER
DISTURBANCE AFFECTING MAINLY THE CENTRAL MTS AND RAMPART RANGE ON
SUNDAY...THEN A DRY MONDAY. LOOK FOR WARMER TEMPS ALL THREE
DAYS...WITH 70S ACROSS THE E PLAINS AND 60S FOR THE HIGH VALLEYS.
TUESDAY AND WEDNESDAY...MODELS ARE TRENDING TOWARDS A MUCH STRONGER
UPPER TROUGH DROPPING OUT OF CANADA ON TUESDAY...BRINGING PCPN BACK
TO THE FORECAST AREA TUES NIGHT THROUGH WEDNESDAY. INCREASED WINDS
AND WAA TUE WOULD MEAN A VERY WARM DAY WITH MAX TEMPS PUSHING 80F ON
THE PLAINS...THEN ABOUT A 10-15 DEGREE COOLDOWN FOR WED. EC AND GFS
MODELS HINT AT THIS SOLUTION...BUT HAVE DIFFERING TIMING AND SYSTEM
STRENGTH SO FORECAST CONFIDENCE IS LOW AT THIS TIME. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1102 AM MDT THU MAR 19 2015
BACK EDGE OF STEADIER/HEAVIER PRECIP ALREADY THROUGH KCOS AS OF
17Z...AND WILL LIKELY MOVE THROUGH KPUB AROUND 19Z. A FEW SHOWERS
WILL STILL LINGER BOTH SITES FOR THE REMAINDER OF THE
AFTERNOON...THOUGH CONDITIONS WILL BE PREDOMINATELY VFR WITH ONLY
SOME BRIEF MVFR UNDER HEAVIER SHOWERS. AT KALS...LOWER CLOUDS AND
A FEW SHOWERS WILL PERSIST INTO THE AFTERNOON...WITH PERIODS OF
MVFR UNTIL 01Z. ALL TERMINALS WILL BECOME VFR THIS EVENING AS
SKIES GRADUALLY CLEAR BEHIND DEPARTING WEATHER SYSTEM...WITH VFR
CONDITIONS OVERNIGHT INTO FRIDAY MORNING.
OVER THE MOUNTAINS...MOST HIGHER TERRAIN WILL REMAIN OBSCURRED BY
-SHRA/-SHSN THROUGH THE AFTERNOON...BEFORE IMPROVING CONDITIONS
WORK FROM NORTH TO SOUTH ACROSS THE AREA EARLY THIS EVENING. BY
06Z...VFR MOST LOCATIONS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ082.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT FRIDAY FOR COZ072-074-079.
WINTER STORM WARNING UNTIL 6 AM MDT FRIDAY FOR COZ073-075-080.
WINTER WEATHER ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ058-
060-076-081.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT FRIDAY FOR COZ066-068.
&&
$$
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
244 PM CDT THU MAR 19 2015
.SHORT TERM...
243 PM CDT
THROUGH SATURDAY...
MAIN FORECAST CONCERNS IN THE NEAR TERM INCLUDE PRECIP CHANCES IN
OUR SOUTHERN COUNTIES TONIGHT...AND A COLD FRONT WHICH WILL BRING
FALLING TEMPERATURES DURING THE DAY SATURDAY...
RADAR IMAGERY SHOWS AREA OF PRECIPITATION ACROSS PORTIONS OF
NORTHERN MISSOURI AND WEST CENTRAL ILLINOIS THIS AFTERNOON
ASSOCIATED WITH AN AREA OF WARM ADVECTION AND BROAD MID-LEVEL
HEIGHT FALLS IN ADVANCE OF A LOW AMPLITUDE WAVE. THIS AREA WILL
SPREAD ENE ACROSS PORTIONS OF MAINLY CENTRAL ILLINOIS THIS EVENING
AND TONIGHT...WITH THE BEST CHANCES FOR PRECIP STAYING SOUTH OF
I-80 IN THE LOCAL FORECAST AREA. EXPECT THE ENTIRE FORECAST AREA
TO BE DRY ON FRIDAY AS SUBSIDENCE OVERSPREADS THE REGION BEHIND
THE DEPARTING UPPER TROUGH. DOWN LOW...WINDS TURN SOUTHWEST IN
ADVANCE OF OUR NEXT SYSTEM HELPING TO ADVECT IN WARMER
TEMPERATURES. MID TO UPPER 50S ARE EXPECTED FRIDAY AFTERNOON.
SOUTHWEST FLOW SHOULD REMAIN STRONG ENOUGH TO PREVENT A LAKE
BREEZE FROM MAKING MUCH IF ANY INLAND PROGRESS TOMORROW.
MEANWHILE...LOW PRESSURE TRACKING ACROSS HUDSON BAY INTO THE
CANADIAN MARITIME PROVINCES TOMORROW WILL DRAG A COLD FRONT INTO
THE NORTHERN GREAT LAKES REGION WITH A WAVE FORMING ALONG THE
FRONT IN THE UPPER MIDWEST AS ANOTHER SHORTWAVE TROUGH DIVES INTO
THE NORTHERN TIER OF STATES. PRECIPITATION WITH THIS SYSTEM SHOULD
REMAIN WELL TO OUR NORTH WITH PRETTY DRY CONDITIONS NOTED IN THE
SOUNDINGS LOCALLY. DO EXPECT HOWEVER THAT THE COLD AIR BEHIND THE
FRONT WILL SURGE DOWN LAKE MICHIGAN PUSHING INTO NORTHERN ILLINOIS
EARLY IN THE DAY SATURDAY RESULTING IN EARLY HIGH TEMPS AND
FALLING TEMPS OFF THE LAKE BY AROUND MIDDAY.
DEUBELBEISS
&&
.LONG TERM...
243 PM CDT
SATURDAY NIGHT THROUGH THURSDAY...
RIDGE OF HIGH PRESSURE WILL BE IN PLACE JUST TO OUR NORTH SATURDAY
NIGHT INTO SUNDAY WITH A WEAK SURFACE LOW OVER THE CENTRAL PLAINS
AND THE LOCAL FORECAST AREA JUST ON THE COLD SIDE OF THE H85
BAROCLINIC ZONE. OVERNIGHT LOWS SHOULD FALL BELOW FREEZING AREA
WIDE SATURDAY NIGHT WITH TEMPERATURES ONLY REBOUNDING INTO THE 40S
SUNDAY. ISENTROPIC ASCENT INCREASES THROUGH THE DAY SUNDAY FOCUSED
FROM SOUTHERN MINNESOTA INTO NORTHERN ILLINOIS. WITH ANTECEDENT
DRY LOW LEVELS AND DRY NORTHEASTERLY FLOW ALSO IN THE LOW
LEVELS...LEANING TOWARDS SLOWER GUIDANCE AS FAR AS OSNET OF
PRECIPITATION SO EXPECT SUNDAY TO BE DRY ACROSS THE FORECAST AREA
WITH PRECIP CHANCES INCREASING FROM THE NORTHWEST LATE SUNDAY
NIGHT INTO MONDAY AS A COMPACT VORT MAX DROPS INTO THE MIDWEST.
DESPITE SURFACE TEMPERATURES EVENTUALLY RISING INTO THE MID TO
UPPER 30S MONDAY...THE DEPTH OF THE NEAR SURFACE WARM LAYER MAY BE
TOO SHALLOW FOR COMPLETE MELTING SO EXPECT PRECIPITATION TO
PRIMARILY FALL AS SNOW. LIGHT ACCUMULATIONS APPEAR POSSIBLE
HOWEVER DIFFERENCES IN THE TRACK PRECLUDE NAILING DOWN ANY OF THE
DETAILS THIS FAR OUT...BUT WOULD PROBABLY ERR ON THE DRIER SIDE
GIVEN SOME OF THE AFOREMENTIONED CONCERNS ABOUT MOISTURE
AVAILABILITY AND SATURATION CONCERNS.
CONTINUE TO MONITOR THE POSSIBILITY OF A MORE DYNAMIC SYSTEM
IMPACTING THE REGION TUESDAY AND WEDNESDAY WITH MODELS CONTINUING TO
ADVERTISE AT LEAST A BRIEF WARMUP THANKS TO 50KT+ LOW LEVEL JET
TRANSPORTING +10C 850MB TEMPS AND PWATS JUST IN EXCESS OF AN INCH
INTO PORTIONS OF THE UPPER MIDWEST. LATEST GFS AND ECMWF BOTH SHOW
THE THERMAL AXIS MOVING ACROSS NORTHERN ILLINOIS TUESDAY NIGHT.
BASED ON CURRENT TIMING OFF THE ECMWF AND GFS...WOULD EXPECT WARMING
TEMPS TUESDAY NIGHT AND CONSERVATIVELY MID TO UPPER 50S
WEDNESDAY...THOUGH GUIDANCE MAY BE UNDER-FORECASTING THE WARMUP.
PRECIPITATION...CLOUD COVER...AND TIMING OF THE COLD FRONT WILL
LIKELY BE LIMITING FACTORS BUT CLIMATOLOGY SUGGESTS WE COULD EASILY
BE ABLE TO GET INTO THE 60S WEDNESDAY. COLD FRONT EVENTUALLY SWEEPS
BACK ACROSS THE REGION MIDWEEK WITH WELL BELOW NORMAL CONDITIONS
RETURNING THE LATTER HALF OF NEXT WEEK.
DEUBELBEISS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WIND SPEEDS AND DIRECTIONS THIS AFTERNOON.
LENNING
//DISCUSSION...UPDATED 18Z...
WINDS HAVE BEEN THE CHALLENGE TODAY...GOING A BIT EARLIER THAN
EXPECTED TO STRONGER SPEEDS AND A MORE EASTERLY DIRECTION THIS
MORNING...AND THEN VEERING SOUTHEASTERLY AGAIN BY EARLY
AFTERNOON WHILE INCREASING FURTHER. SPEEDS ARE EXPECTED TO RELAX
SOMEWHAT THIS AFTERNOON BUT THE DIRECTION MAY AGAIN TURN MORE
EASTERLY IF A LAKE BREEZE INFLUENCE DEVELOPS...SO GETTING BACK TO
A MORE FAVORABLE CONFIGURATION AT ORD MAY HAVE TO WAIT UNTIL LATER
THIS EVENING...PROBABLY AFTER THE PEAK RUSH.
ALSO MAINTAINED THE MENTION OF SHRA FOR LATER THIS EVENING BUT GIVEN
THE DRY AIR IN PLACE TODAY IT COULD BE HARD TO GET MORE THAN SOME
SPRINKLES OR BRIEF LIGHT RAIN SHOWERS.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM FOR WIND AND LOW FOR SHRA CHANCES BUT OTHERWISE HIGH.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF SNOW LATE.
MONDAY...CHANCE OF SNOW.
TUESDAY...CHANCE OF RAIN/SNOW LATE.
WEDNESDAY...CHANCE OF RAIN.
RODRIGUEZ
&&
.MARINE...
203 PM CDT
AS HIGH PRESSURE CONTINUES TO MOVE FROM THE EASTERN GREAT LAKES TO
THE EAST...GENERALLY SELY HAS DEVELOPED OVER LAKE MICHIGAN. A WEAK
GRADIENT OVER THE SOUTHERN PORTIONS OF THE LAKE HAVE ALLOWED A
PSEUDO-LAKE BREEZE TO DEVELOP WITH WINDS MORE ELY OVER THE NEARSHORE
WATERS ALONG THE ILLINOIS COAST...WHILE WINDS REMAIN SELY OVER THE
INDIANA NEARSHORE WATERS. AS THE HIGH CONTINUES TO THE EAST TONIGHT
AND LOW PRESSURE TRACKS ACROSS THE CANADIAN PRAIRIES...WITH A
TRAILING COLD FRONT EXTENDING INTO THE NRN PLAINS...WINDS WILL VEER
TO SOUTHERLY BY FRIDAY MORNING. THE COMBINATION OF A SLOW MOVING
HIGH MOVING OFF TO THE EAST AND A FASTER MOVING SFC TROUGH AND
ASSOCIATED COLD FRONT FROM THE WEST...WILL LEAD TO STRENGTHENING
SLY WINDS THROUGH FRIDAY INTO FRIDAY EVENING WITH SPEEDS INCREASING
TO 20-25KT...WITH THE STRONGEST WINDS OVER THE NRN PORTIONS OF THE
LAKE WHERE THE GRADIENT WILL BE STRONGEST. THE COLD FRONT IS
EXPECTED TO PUSH SOUTH DOWN THE LAKE LATE FRIDAY NIGHT...INTO
SATURDAY MORNING...TURNING WINDS MORE NORTHERLY AND DRAWING COLDER
AIR DOWN THE LAKE. THE INCREASING COLD ADVECTION AS ANOTHER ARCTIC
HIGH BUILDS OUT OF CANADA AND INTO THE UPPER MISSISSIPPI VALLEY AND
WESTERN GREAT LAKES SHOULD HELP BRING THE NORTHERLY WINDS BACK UP TO
20-25KT SATURDAY NIGHT AND INTO SUNDAY. WHILE GALES ARE NOT
EXPECTED FOLLOWING THE FRONTAL PASSAGE...THE EXTENDED NORTHERLY
FETCH SHOULD LEAD TO SMALL CRAFT ADVISORY CONDITIONS FOR BOTH THE
ILLINOIS AND INDIANA NEARSHORE WATERS FOR SATURDAY NIGHT AND SUNDAY.
WINDS WILL GRADUALLY VEER TO NORTHEASTERLY TO EASTERLY SUNDAY NIGHT
AND MONDAY AS THE HIGH BUILDS ACROSS THE EASTERN GREAT LAKES AND
WEAK LOW PRESSURE DEVELOPING OVER THE CENTRAL PLAINS SUNDAY TRACKS
EAST TO THE LOWER OHIO VALLEY BEFORE WEAKENING TO AN OPEN TROUGH
EXTENDING FROM TENNESSEE TO WESTERN PENNSYLVANIA EARLY NEXT WEEK.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
211 PM CDT Thu Mar 19 2015
.SHORT TERM...(Tonight)
ISSUED AT 209 PM CDT THU MAR 19 2015
Area of rain across Missouri has spread into west central Illinois
early this afternoon, with some light rain being reported as far
east as Jacksonville at 2 pm. Still quite a bit of dry air
underneath this rain, with temp/dew point spreads around 15 degrees,
so amounts will remain rather light this afternoon. Latest HRRR and
NAM spread this eastward centered along the Jacksonville-Paris
corridor through the afternoon, reaching the Indiana border toward
4-5 pm., with a southern extent generally along I-70. Any northward
extension past Peoria would be more likely very late afternoon. The
bulk of the precipitation should be east of the forecast area by
around midnight or so, but some drizzle is likely to linger
overnight, especially in the south half of the forecast area, where
stratus should become extensive after midnight. Little change made
to the temperatures, with lows 35-38 in most areas.
&&
.LONG TERM...(Friday through Thursday)
ISSUED AT 209 PM CDT THU MAR 19 2015
Split-flow pattern continues into the end of the week as deep trough
continues to pivot over the Hudson Bay area and southern stream
energy moves slowly over the southwest U.S.. Wave embedded in the
northern stream trough should exit the forecast area Friday bringing
gradual clearing and seasonal temperatures.
Next northern stream wave and associated cold front is expected to
impact the area on Saturday. Significant spread on frontal passage
timing is evident in operational model suite and SREF which has
major implications on temperatures for Saturday, particularly across
the central forecast area. Northern tier of area see passage before
peak heating in most of the solutions with I-70 southward not
impacted by cold advection until well after peak heating through the
solution envelope. Its the I-72/Danville corridor which has the
largest impact of this difference in timing. Operational 12Z NAM is
slow enough to suggest some lower 70s are possible across southwest
forecast area, however, the model seems to be on the warm side of the
SREF envelope. For now will be leaning toward the cooler, but still
above normal, GFS/SREF Mean timing. Either way, moisture remains
shunted south and east of Illinois so passage will be dry.
Much cooler temperatures will move into the region behind the front
with progged 850 mb temps expected below freezing across the
northern half of the area by Monday.
Models are suggesting a temporary transition to a more progressive
zonal pattern by early next week. The initial wave in this pattern
shift is progged to move eastward into Illinois Monday. Low-level
temperatures remain cool and Bufkit soundings suggest a mix of
precip may be possible late Sunday Night and early Monday across
northern portions of the forecast area. The southern stream energy
moving across the southern tier of the country is expected to be
over the eastern Gulf of Mexico by Sunday Night shunting any Gulf
moisture east limiting moisture available in the Midwest, so QPF
will likely be limited to a few tenths of liquid at most.
Phased ridging develops over the Mississippi Valley by Tuesday
allowing temps to respond rapidly. With the phasing, Gulf moisture
is available for the next wave expected to push into the state on
Wednesday. Latest model suite are fairly consistent on bringing 850
temps into the 10C range with surface dew points into the 50s.
Timing of the waves associated cold front will have an impact on any
potential instability and if a passage does occur near peak heating
can not rule out the potential for thunder, particularly across
southeast Illinois Wednesday afternoon and evening.
At this time, GFS and ECMWF suggest the strong wave on Wednesday
will assist in a transition back to a ridge west/trough east
longwave pattern allowing cold air to once again plummet into the
midwest. With 850 mb temps expected to be below 0C by Thursday
afternoon, highs on Thursday may struggle to make it out of the 40s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1230 PM CDT THU MAR 19 2015
Main forecast issue will be with development of MVFR/IFR
conditions later this afternoon and evening. MVFR ceilings
spreading toward the IL/MO border with IFR conditions underneath
the rain further west in Missouri. Some moistening of the lower
levels of the atmosphere will need to take place as the
precipitation arrives in central Illinois over the next few hours,
so current thinking is that ceilings below 3,000 feet will start
moving into KPIA/KSPI after 22-23Z and encompassing the remaining
TAF sites this evening. Have introduced some IFR ceilings from
KSPI-KCMI overnight, becoming more widespread as the rain exits in
the 05-09Z time frame. Further north, have kept KPIA/KBMI as MVFR
overnight. Some clearing should begin Friday morning from the
northwest, but a passing upper trough will likely keep MVFR
ceilings in much of central Illinois through a good part of the
morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Geelhart
LONG TERM...Barker
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1241 PM CDT THU MAR 19 2015
.SHORT TERM...
325 AM CDT
TODAY AND TONIGHT...
MAIN FORECAST CHALLENGES ARE WITH PRECIP TRENDS THIS EVENING
THROUGH THE OVERNIGHT HOURS MAINLY ACROSS THE SOUTHERN THIRD OF
THE CWA WITH PRIMARILY RAIN EXPECTED...BUT WITH THE POSSIBILITY
FOR A BRIEF WINDOW OF A RAIN SNOW MIX.
QUIET CONDITIONS IN THE NEAR TERM AS HIGH PRESSURE SPANS THE
GREAT LAKES REGION. MID/HIGH CLOUDS CONTINUE TO SPREAD OVERHEAD
FROM BOTH THE SOUTHERN STREAM ENERGY AND APPROACHING MID LEVEL
TROUGH OVER THE NORTHERN PLAINS. CURRENT CLOUDY CONDITIONS WILL
REMAIN POSSIBLY BRIEFLY THINNING AT TIMES FOR A TIME THIS
MORNING...BUT WITH INCREASING CLOUDS EXPECTED ONCE AGAIN THROUGH
MIDDAY. DESPITE CLOUDS IN PLACE...HIGHS AROUND 50 ARE EXPECTED
TODAY WITH SLIGHTLY COOLER CONDITIONS IN THE LOW TO MID 40S NEAR
THE LAKE.
THE BULK OF THE PRECIP THIS MORNING REMAINS WELL SOUTH OF THE
AREA OVER THE CENTRAL PLAINS AND MID MISSISSIPPI VALLEY. GUIDANCE
CONTINUES TO SHOW THAT THIS PRECIP WILL BLOSSOM FURTHER NORTH
LATER THIS AFTERNOON AND EARLY EVENING. THIS WILL BE IN RESPONSE
TO PERSISTENT SHORT WAVE ENERGY...WAA...AND BETTER LARGE SCALE
SUPPORT WITH APPROACHING TROUGH FROM THE NORTHWEST. HOWEVER...IT
DOES APPEAR THAT THIS WILL BE FOCUSED MORE ALONG THE SOUTHERN
THIRD OF THE CWA WITH THE FAR SOUTHERN TIER HAVING THE BEST
CHANCE. DID INCLUDE LIKELY POPS IN THIS LOCATION WITH CHANCE TO
SLIGHT CHANCE POPS FURTHER NORTH...JUST NORTH OF THE I80 CORRIDOR.
PRECIP WILL LIKELY STAY ALONG AND SOUTH OF I80 BUT WITH GUIDANCE
STILL VARYING TO THE NORTHERN EXTENT OF THIS PRECIP
SHIELD...WANTED TO KEEP AT LEAST SLIGHT CHANCE POPS SLIGHTLY
FURTHER NORTH. TIMING APPEARS TO BE FROM EARLY EVENING TO LATE
EVENING WITH IT THEN EXITING AFTER THE MIDNIGHT TIME FRAME.
THERMAL PROFILES SUGGEST ALL RAIN OVER THE ENTIRE CWA BUT IT DOES
LOOK LIKE THERE COULD BE A PERIOD WHEN SOME LOCATIONS COULD
OBSERVE A BRIEF WINDOW OF A RAIN SNOW MIX. HOWEVER...NOT OVERLY
EXCITED WITH THIS POSSIBILITY AND HAVE LEFT OUT ANY MENTION OF
SNOW IN THE GRIDS. LOW TEMPS TONIGHT WILL BE IN THE MID TO UPPER
30S...AND AM NOT CONCERNED WITH ANY FREEZING POTENTIAL AT THIS
TIME.
RODRIGUEZ
&&
.LONG TERM...
214 AM CDT
FRIDAY THROUGH WEDNESDAY...
500MB TROUGH AXIS WILL BE PIVOTING EAST ACROSS THE REGION FRI
MORNING...WITH A WEAK LOW SKIRTING THE OHIO VALLEY AND ANOTHER LOW
WELL NORTH OVER JAMES BAY. THIS WILL PLACE THE FORECAST AREA IN A
WEAK DIFFLUENCE ZONE WITH DEPARTING LOW/MID LVL MOISTURE. THE
RESULT APPEARS TO BE A QUICK SURGE IN A 850MB THERMAL RIDGE OF 6
TO 9 DEG C AIR LIFTING NORTHEAST ACROSS THE CWFA. SFC TEMPS SHUD
REBOUND INTO THE MID/UPR 50S. THE LONGWAVE PATTERN
FLATTENS...ALLOWING FOR A SLIGHTLY MORE PROGRESSIVE FLOW HEADING
INTO THE WEEKEND. WITH THE AFOREMENTIONED LOW NEAR JAMES
BAY...THIS WILL SETUP A TRAILING FRONTAL BOUNDARY THAT WILL
STRETCH SOUTHWEST ACROSS THE UPPER MIDWEST LATE FRI. THIS FEATURE
WILL BECOME A FOCAL POINT SAT AFTN/EVE FOR A SHARPENING BAROCLINIC
ZONE.
GUIDANCE CONTINUES TO KEEP THE ENVIRONMENT RELATIVELY DRY SAT INTO
SAT NIGHT...HOWEVER THE FRONTAL BOUNDARY WILL BE SLIDING SOUTH
ACROSS THE FORECAST AREA SAT AFTN/EVE WITH MUCH COOLER AIR. CANADIAN
SFC RIDGE WILL PUSH SOUTHEAST INTO THE UPPER MIDWEST/NORTHERN GREAT
LAKES SAT AFTN/EVE. SIMULATNEOUSLY GUIDANCE HAS PROGGED A WEAK LOBE
OF VORTICITY TO EJECT FROM THE CENTRAL ROCKIES AND DEVELOP A SFC
WAVE SAT NGT. THIS FEATURE WILL INTERACT WITH THE FRONTAL BOUNDARY
EARLY SUN...WITH A STEADY FEED OF MOISTURE INTO THE MID-MISSOURI
VALLEY. THE PRECIP SHIELD SHUD EVENTUALLY OVERCOME THE DRY NEAR SFC
CONDS...AND ARRIVE OVER THE CWFA SUN EVE. SOUNDINGS WOULD SUGGEST
PRECIP FALLING AS LGT SNOW...HOWEVER ENOUGH WARMTH COULD PROVIDE A
RA/SN MIX AT THE ONSET BEFORE DYNAMICALLY COOLING TO ALL SNOW.
TEMPS SUN WILL LIKELY REMAIN IN THE LOW/MID 40S...HOWEVER COULD SEE
TEMPS A FEW DEGREES COOLER BY MID/LATE AFTN.
MONDAY THROUGH THURSDAY... ENSEMBLES CONTINUE THE THEME OF TROUGHING
ACROSS THE GREAT LAKES THRU EARLY NEXT WEEK...WITH THE HIGH
AMPLITUDE RIDGING RELAXING TOWARDS MID-WEEK AND TRANSITIONING INTO A
SLIGHTLY MORE FLAT FLOW. UNSEASONABLY COOL AIR FOR MON WITH HIGHS
MAINLY IN THE UPR 30S...THEN BEGINNING TO REBOUND TUE INTO THE MID
40S. SFC RIDGE PUSHES EAST MID-WEEK...WITH WHAT APPEARS TO BE A
QUICK WARM PUSH AGAIN WED. BY THE MIDDLE OF NEXT WEEK GUIDANCE HAS
YET ANOTHER SHORTWAVE ARRIVING...AND APPEARS SOME INSTABILITY COULD
ACCOMPANY IT.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WIND SPEEDS AND DIRECTIONS THIS AFTERNOON.
LENNING
//DISCUSSION...UPDATED 18Z...
WINDS HAVE BEEN THE CHALLENGE TODAY...GOING A BIT EARLIER THAN
EXPECTED TO STRONGER SPEEDS AND A MORE EASTERLY DIRECTION THIS
MORNING...AND THEN VEERING SOUTHEASTERLY AGAIN BY EARLY
AFTERNOON WHILE INCREASING FURTHER. SPEEDS ARE EXPECTED TO RELAX
SOMEWHAT THIS AFTERNOON BUT THE DIRECTION MAY AGAIN TURN MORE
EASTERLY IF A LAKE BREEZE INFLUENCE DEVELOPS...SO GETTING BACK TO
A MORE FAVORABLE CONFIGURATION AT ORD MAY HAVE TO WAIT UNTIL LATER
THIS EVENING...PROBABLY AFTER THE PEAK RUSH.
ALSO MAINTAINED THE MENTION OF SHRA FOR LATER THIS EVENING BUT GIVEN
THE DRY AIR IN PLACE TODAY IT COULD BE HARD TO GET MORE THAN SOME
SPRINKLES OR BRIEF LIGHT RAIN SHOWERS.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM FOR WIND AND LOW FOR SHRA CHANCES BUT OTHERWISE HIGH.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF SNOW LATE.
MONDAY...CHANCE OF SNOW.
TUESDAY...CHANCE OF RAIN/SNOW LATE.
WEDNESDAY...CHANCE OF RAIN.
RODRIGUEZ
&&
.MARINE...
214 AM CDT
DEPARTING SURFACE RIDGE TO THE EAST WILL ALLOW WINDS TO BECOME
SOUTHEASTERLY THEN SOUTHWESTERLY BY FRI EVENING. AN AREA OF LOW
PRESSURE WILL LIFT NORTHEAST ACROSS ONTARIO TO JAMES BAY
FRI...WITH A TRAILING FRONTAL BOUNDARY STRETCHED SOUTHWEST ACROSS
THE UPPER MIDWEST. HIGH PRESSURE WILL ALSO BE STRETCHED ACROSS THE
OHIO VALLEY AND INFLUENCE THE BULK OF LAKE MICHIGAN FRI INTO FRI
NGT. A WEAK LOW IS EXPECTED TO THEN DEVELOP FRI EVENING ALONG THE
SOUTHWEST PORTION OF THE LOW AND SLIDE EAST ACROSS CENTRAL LAKE
MICHIGAN EARLY SAT. THIS WILL HELP TO PUSH THE FRONTAL BOUNDARY
FURTHER SOUTH AND CLEAR THE LAKE BY SAT AFTN...WITH WINDS TURNING
NORTH/NORTHEAST BEHIND THE FRONT. THEN HIGH PRESSURE ACROSS
CENTRAL CANADA WILL SLIDE SOUTHEAST ACROSS THE UPPER MIDWEST
SUN...WITH A TIGHTENING GRADIENT ACROSS THE SOUTHERN THIRD OF THE
LAKE AND WINDS TURNING EAST AND SOUTHEAST ACROSS THE SOUTHERN
TIP. HIGH PRESSURE THEN SPREADS SLOWLY SOUTHEAST ACROSS THE LAKE
MON INTO TUE...WITH A MUCH LIGHTER PRESSURE GRADIENT.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1230 PM CDT Thu Mar 19 2015
.UPDATE...
ISSUED AT 954 AM CDT THU MAR 19 2015
Narrow west-east bands of echoes continue to appear on radar,
mostly near the I-70 corridor. Some periodic light rain has been
reported, but there were also some sleet reports as well near
Effingham. Some more widespread rain showers were occurring in
central and west central Missouri, and latest runs of the HRRR and
NAM show this increasing as it moves eastward this afternoon ahead
of a shortwave that will be moving out of the Dakotas. Have sent
some refinements of the rain chances in the grids/zones, focusing
the best chances from about mid afternoon through late evening. No
significant changes made to temperatures.
&&
.SHORT TERM...(Today)
ISSUED AT 327 AM CDT THU MAR 19 2015
Dissipating short-wave tracking into the Tennessee River Valley has
spread light rain as far north as south-central Illinois early this
morning, with 07Z/2am radar imagery showing precip just south of a
Jacksonville to Paris line. 00Z KILX upper air sounding featured
plenty of dry air below 700mb, which is effectively keeping the
precip from spreading any further north. Recent radar trends and
HRRR forecasts support this as well, showing the light rain staying
across the far southern KILX CWA through mid-morning. As the
initial wave ripples by to the south, a second northern-stream
wave currently evident on water vapor imagery over the western
Dakotas will approach from the northwest later in the day. All
models suggest this feature will draw moisture currently across
Missouri/southern Illinois back northward this afternoon. Given
initially dry low-level air mass and continued easterly flow, think
this will be a slow process. Have therefore slowed the northward
spread of precip, delaying it across much of the CWA until
afternoon. In fact, areas around Rantoul and Danville may stay dry
until closer to evening. Further west, have raised PoPs to likely
along/west of a Peoria to Mattoon line this afternoon. Due to
extensive cloud cover, light easterly winds, and eventually light
rain...have undercut the warm MAV guidance by several degrees. High
temperatures will range from the middle 40s far southwest around
Jacksonville to around 50 degrees along/east of I-57.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 327 AM CDT THU MAR 19 2015
Light rain will be ongoing across much of the area this evening, as
short-wave tracks into the southern Great Lakes. As this feature
moves further east, the rain will come to an end from west to east
overnight. Total rainfall through tonight will generally range from
one tenth to one quarter of an inch.
High pressure will build into the region on Friday, providing dry
and seasonably warm conditions with highs well into the 50s. Even
warmer weather is expected on Saturday, as southwesterly winds
increase in advance of an approaching cold front. Boundary will pass
through Saturday afternoon/evening, but before it does, high
temperatures will climb into the lower to middle 60S. Once front
exits, a chilly air mass will settle into the area for early next
week.
00Z Mar 19 models continue to show a clipper system approaching from
the northwest Sunday night into Monday, with minor timing
differences noted. Given presence of initially dry air mass beneath
surface high pressure on Sunday, think precip with this feature will
be delayed. As a result, will keep Sunday evening dry with chance
PoPs spreading across the western half of the CWA overnight. With
850mb temps in the 0 to -5C range and ample evaporational cooling
occurring, think precip type will be snow or a rain/snow mix. This
wintry precip will continue into Monday morning before surface temps
warm sufficiently to support all rain by midday. The clipper will
be weakening as it tracks southeastward across the area and with
temps quickly climbing above freezing Monday morning, am expecting
little or no snow accumulation.
Once this system passes, cool/dry weather will be on tap for Tuesday
before yet another wave and its associated cold front approach on
Wednesday. GFS/ECMWF are in good agreement concerning timing of
this system, with both models spreading rain into Illinois Tuesday
night into Wednesday. Will carry high chance PoPs accordingly,
with southerly flow ahead of the cold front pushing high temps
back into the upper 50s and lower 60s on Wednesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1230 PM CDT THU MAR 19 2015
Main forecast issue will be with development of MVFR/IFR
conditions later this afternoon and evening. MVFR ceilings
spreading toward the IL/MO border with IFR conditions underneath
the rain further west in Missouri. Some moistening of the lower
levels of the atmosphere will need to take place as the
precipitation arrives in central Illinois over the next few hours,
so current thinking is that ceilings below 3,000 feet will start
moving into KPIA/KSPI after 22-23Z and encompassing the remaining
TAF sites this evening. Have introduced some IFR ceilings from
KSPI-KCMI overnight, becoming more widespread as the rain exits in
the 05-09Z time frame. Further north, have kept KPIA/KBMI as MVFR
overnight. Some clearing should begin Friday morning from the
northwest, but a passing upper trough will likely keep MVFR
ceilings in much of central Illinois through a good part of the
morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1115 AM CDT THU MAR 19 2015
.SHORT TERM...
325 AM CDT
TODAY AND TONIGHT...
MAIN FORECAST CHALLENGES ARE WITH PRECIP TRENDS THIS EVENING
THROUGH THE OVERNIGHT HOURS MAINLY ACROSS THE SOUTHERN THIRD OF
THE CWA WITH PRIMARILY RAIN EXPECTED...BUT WITH THE POSSIBILITY
FOR A BRIEF WINDOW OF A RAIN SNOW MIX.
QUIET CONDITIONS IN THE NEAR TERM AS HIGH PRESSURE SPANS THE
GREAT LAKES REGION. MID/HIGH CLOUDS CONTINUE TO SPREAD OVERHEAD
FROM BOTH THE SOUTHERN STREAM ENERGY AND APPROACHING MID LEVEL
TROUGH OVER THE NORTHERN PLAINS. CURRENT CLOUDY CONDITIONS WILL
REMAIN POSSIBLY BRIEFLY THINNING AT TIMES FOR A TIME THIS
MORNING...BUT WITH INCREASING CLOUDS EXPECTED ONCE AGAIN THROUGH
MIDDAY. DESPITE CLOUDS IN PLACE...HIGHS AROUND 50 ARE EXPECTED
TODAY WITH SLIGHTLY COOLER CONDITIONS IN THE LOW TO MID 40S NEAR
THE LAKE.
THE BULK OF THE PRECIP THIS MORNING REMAINS WELL SOUTH OF THE
AREA OVER THE CENTRAL PLAINS AND MID MISSISSIPPI VALLEY. GUIDANCE
CONTINUES TO SHOW THAT THIS PRECIP WILL BLOSSOM FURTHER NORTH
LATER THIS AFTERNOON AND EARLY EVENING. THIS WILL BE IN RESPONSE
TO PERSISTENT SHORT WAVE ENERGY...WAA...AND BETTER LARGE SCALE
SUPPORT WITH APPROACHING TROUGH FROM THE NORTHWEST. HOWEVER...IT
DOES APPEAR THAT THIS WILL BE FOCUSED MORE ALONG THE SOUTHERN
THIRD OF THE CWA WITH THE FAR SOUTHERN TIER HAVING THE BEST
CHANCE. DID INCLUDE LIKELY POPS IN THIS LOCATION WITH CHANCE TO
SLIGHT CHANCE POPS FURTHER NORTH...JUST NORTH OF THE I80 CORRIDOR.
PRECIP WILL LIKELY STAY ALONG AND SOUTH OF I80 BUT WITH GUIDANCE
STILL VARYING TO THE NORTHERN EXTENT OF THIS PRECIP
SHIELD...WANTED TO KEEP AT LEAST SLIGHT CHANCE POPS SLIGHTLY
FURTHER NORTH. TIMING APPEARS TO BE FROM EARLY EVENING TO LATE
EVENING WITH IT THEN EXITING AFTER THE MIDNIGHT TIME FRAME.
THERMAL PROFILES SUGGEST ALL RAIN OVER THE ENTIRE CWA BUT IT DOES
LOOK LIKE THERE COULD BE A PERIOD WHEN SOME LOCATIONS COULD
OBSERVE A BRIEF WINDOW OF A RAIN SNOW MIX. HOWEVER...NOT OVERLY
EXCITED WITH THIS POSSIBILITY AND HAVE LEFT OUT ANY MENTION OF
SNOW IN THE GRIDS. LOW TEMPS TONIGHT WILL BE IN THE MID TO UPPER
30S...AND AM NOT CONCERNED WITH ANY FREEZING POTENTIAL AT THIS
TIME.
RODRIGUEZ
&&
.LONG TERM...
214 AM CDT
FRIDAY THROUGH WEDNESDAY...
500MB TROUGH AXIS WILL BE PIVOTING EAST ACROSS THE REGION FRI
MORNING...WITH A WEAK LOW SKIRTING THE OHIO VALLEY AND ANOTHER LOW
WELL NORTH OVER JAMES BAY. THIS WILL PLACE THE FORECAST AREA IN A
WEAK DIFFLUENCE ZONE WITH DEPARTING LOW/MID LVL MOISTURE. THE
RESULT APPEARS TO BE A QUICK SURGE IN A 850MB THERMAL RIDGE OF 6
TO 9 DEG C AIR LIFTING NORTHEAST ACROSS THE CWFA. SFC TEMPS SHUD
REBOUND INTO THE MID/UPR 50S. THE LONGWAVE PATTERN
FLATTENS...ALLOWING FOR A SLIGHTLY MORE PROGRESSIVE FLOW HEADING
INTO THE WEEKEND. WITH THE AFOREMENTIONED LOW NEAR JAMES
BAY...THIS WILL SETUP A TRAILING FRONTAL BOUNDARY THAT WILL
STRETCH SOUTHWEST ACROSS THE UPPER MIDWEST LATE FRI. THIS FEATURE
WILL BECOME A FOCAL POINT SAT AFTN/EVE FOR A SHARPENING BAROCLINIC
ZONE.
GUIDANCE CONTINUES TO KEEP THE ENVIRONMENT RELATIVELY DRY SAT INTO
SAT NIGHT...HOWEVER THE FRONTAL BOUNDARY WILL BE SLIDING SOUTH
ACROSS THE FORECAST AREA SAT AFTN/EVE WITH MUCH COOLER AIR. CANADIAN
SFC RIDGE WILL PUSH SOUTHEAST INTO THE UPPER MIDWEST/NORTHERN GREAT
LAKES SAT AFTN/EVE. SIMULATNEOUSLY GUIDANCE HAS PROGGED A WEAK LOBE
OF VORTICITY TO EJECT FROM THE CENTRAL ROCKIES AND DEVELOP A SFC
WAVE SAT NGT. THIS FEATURE WILL INTERACT WITH THE FRONTAL BOUNDARY
EARLY SUN...WITH A STEADY FEED OF MOISTURE INTO THE MID-MISSOURI
VALLEY. THE PRECIP SHIELD SHUD EVENTUALLY OVERCOME THE DRY NEAR SFC
CONDS...AND ARRIVE OVER THE CWFA SUN EVE. SOUNDINGS WOULD SUGGEST
PRECIP FALLING AS LGT SNOW...HOWEVER ENOUGH WARMTH COULD PROVIDE A
RA/SN MIX AT THE ONSET BEFORE DYNAMICALLY COOLING TO ALL SNOW.
TEMPS SUN WILL LIKELY REMAIN IN THE LOW/MID 40S...HOWEVER COULD SEE
TEMPS A FEW DEGREES COOLER BY MID/LATE AFTN.
MONDAY THROUGH THURSDAY... ENSEMBLES CONTINUE THE THEME OF TROUGHING
ACROSS THE GREAT LAKES THRU EARLY NEXT WEEK...WITH THE HIGH
AMPLITUDE RIDGING RELAXING TOWARDS MID-WEEK AND TRANSITIONING INTO A
SLIGHTLY MORE FLAT FLOW. UNSEASONABLY COOL AIR FOR MON WITH HIGHS
MAINLY IN THE UPR 30S...THEN BEGINNING TO REBOUND TUE INTO THE MID
40S. SFC RIDGE PUSHES EAST MID-WEEK...WITH WHAT APPEARS TO BE A
QUICK WARM PUSH AGAIN WED. BY THE MIDDLE OF NEXT WEEK GUIDANCE HAS
YET ANOTHER SHORTWAVE ARRIVING...AND APPEARS SOME INSTABILITY COULD
ACCOMPANY IT.
BEACHLER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* WINDS HAVE INCREASED AS PREVIOUSLY MENTIONED AND REMAIN JUST
SOUTH OF EASTERLY BUT ARE EXPECTED TO RELAX A BIT THIS
AFTERNOON.
LENNING
//DISCUSSION...UPDATED 12Z...
VFR CONDITIONS WILL CONTINUE THIS FORECAST PERIOD WITH A LOW
CHANCE OF RAIN LATER THIS EVENING. LATEST TRENDS WOULD SUGGEST
THE BULK OF THIS RAIN WILL STAY SOUTH OF THE TERMINALS...WITH THE
NORTHERN EDGE OF THIS PRECIP LIKELY NEARING ORD/MDW BUT WITH GYY
HAVING THE BEST CHANCE. LIGHT EAST SOUTHEAST WINDS THIS MORNING
ARE EXPECTED TO SLOWLY INCREASE LATER THIS MORNING...AS LAKE
INFLUENCE HELPS WINDS BECOME MORE EAST NORTHEAST BY MIDDAY.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM FOR WIND...OTHERWISE HIGH. WINDS LIKELY STAYING BETWEEN
EAST AND SOUTHEAST AND IN THE TEENS...WITH GUSTS TO AROUND 20 IN
THE LATE MORNING AND EARLY AFTERNOON.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF SNOW LATE.
MONDAY...CHANCE OF SNOW.
TUESDAY...CHANCE OF RAIN/SNOW LATE.
WEDNESDAY...CHANCE OF RAIN.
RODRIGUEZ
&&
.MARINE...
214 AM CDT
DEPARTING SURFACE RIDGE TO THE EAST WILL ALLOW WINDS TO BECOME
SOUTHEASTERLY THEN SOUTHWESTERLY BY FRI EVENING. AN AREA OF LOW
PRESSURE WILL LIFT NORTHEAST ACROSS ONTARIO TO JAMES BAY
FRI...WITH A TRAILING FRONTAL BOUNDARY STRETCHED SOUTHWEST ACROSS
THE UPPER MIDWEST. HIGH PRESSURE WILL ALSO BE STRETCHED ACROSS THE
OHIO VALLEY AND INFLUENCE THE BULK OF LAKE MICHIGAN FRI INTO FRI
NGT. A WEAK LOW IS EXPECTED TO THEN DEVELOP FRI EVENING ALONG THE
SOUTHWEST PORTION OF THE LOW AND SLIDE EAST ACROSS CENTRAL LAKE
MICHIGAN EARLY SAT. THIS WILL HELP TO PUSH THE FRONTAL BOUNDARY
FURTHER SOUTH AND CLEAR THE LAKE BY SAT AFTN...WITH WINDS TURNING
NORTH/NORTHEAST BEHIND THE FRONT. THEN HIGH PRESSURE ACROSS
CENTRAL CANADA WILL SLIDE SOUTHEAST ACROSS THE UPPER MIDWEST
SUN...WITH A TIGHTENING GRADIENT ACROSS THE SOUTHERN THIRD OF THE
LAKE AND WINDS TURNING EAST AND SOUTHEAST ACROSS THE SOUTHERN
TIP. HIGH PRESSURE THEN SPREADS SLOWLY SOUTHEAST ACROSS THE LAKE
MON INTO TUE...WITH A MUCH LIGHTER PRESSURE GRADIENT.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
956 AM CDT Thu Mar 19 2015
.UPDATE...
ISSUED AT 954 AM CDT THU MAR 19 2015
Narrow west-east bands of echoes continue to appear on radar,
mostly near the I-70 corridor. Some periodic light rain has been
reported, but there were also some sleet reports as well near
Effingham. Some more widespread rain showers were occurring in
central and west central Missouri, and latest runs of the HRRR and
NAM show this increasing as it moves eastward this afternoon ahead
of a shortwave that will be moving out of the Dakotas. Have sent
some refinements of the rain chances in the grids/zones, focusing
the best chances from about mid afternoon through late evening. No
significant changes made to temperatures.
&&
.SHORT TERM...(Today)
ISSUED AT 327 AM CDT THU MAR 19 2015
Dissipating short-wave tracking into the Tennessee River Valley has
spread light rain as far north as south-central Illinois early this
morning, with 07Z/2am radar imagery showing precip just south of a
Jacksonville to Paris line. 00Z KILX upper air sounding featured
plenty of dry air below 700mb, which is effectively keeping the
precip from spreading any further north. Recent radar trends and
HRRR forecasts support this as well, showing the light rain staying
across the far southern KILX CWA through mid-morning. As the
initial wave ripples by to the south, a second northern-stream
wave currently evident on water vapor imagery over the western
Dakotas will approach from the northwest later in the day. All
models suggest this feature will draw moisture currently across
Missouri/southern Illinois back northward this afternoon. Given
initially dry low-level air mass and continued easterly flow, think
this will be a slow process. Have therefore slowed the northward
spread of precip, delaying it across much of the CWA until
afternoon. In fact, areas around Rantoul and Danville may stay dry
until closer to evening. Further west, have raised PoPs to likely
along/west of a Peoria to Mattoon line this afternoon. Due to
extensive cloud cover, light easterly winds, and eventually light
rain...have undercut the warm MAV guidance by several degrees. High
temperatures will range from the middle 40s far southwest around
Jacksonville to around 50 degrees along/east of I-57.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 327 AM CDT THU MAR 19 2015
Light rain will be ongoing across much of the area this evening, as
short-wave tracks into the southern Great Lakes. As this feature
moves further east, the rain will come to an end from west to east
overnight. Total rainfall through tonight will generally range from
one tenth to one quarter of an inch.
High pressure will build into the region on Friday, providing dry
and seasonably warm conditions with highs well into the 50s. Even
warmer weather is expected on Saturday, as southwesterly winds
increase in advance of an approaching cold front. Boundary will pass
through Saturday afternoon/evening, but before it does, high
temperatures will climb into the lower to middle 60S. Once front
exits, a chilly air mass will settle into the area for early next
week.
00Z Mar 19 models continue to show a clipper system approaching from
the northwest Sunday night into Monday, with minor timing
differences noted. Given presence of initially dry air mass beneath
surface high pressure on Sunday, think precip with this feature will
be delayed. As a result, will keep Sunday evening dry with chance
PoPs spreading across the western half of the CWA overnight. With
850mb temps in the 0 to -5C range and ample evaporational cooling
occurring, think precip type will be snow or a rain/snow mix. This
wintry precip will continue into Monday morning before surface temps
warm sufficiently to support all rain by midday. The clipper will
be weakening as it tracks southeastward across the area and with
temps quickly climbing above freezing Monday morning, am expecting
little or no snow accumulation.
Once this system passes, cool/dry weather will be on tap for Tuesday
before yet another wave and its associated cold front approach on
Wednesday. GFS/ECMWF are in good agreement concerning timing of
this system, with both models spreading rain into Illinois Tuesday
night into Wednesday. Will carry high chance PoPs accordingly,
with southerly flow ahead of the cold front pushing high temps
back into the upper 50s and lower 60s on Wednesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
ISSUED AT 607 AM CDT THU MAR 19 2015
VFR conditions will prevail at all TAF sites this morning and into
early afternoon. Then as clouds lower during the afternoon, will
include VCSH to catch any light rain showers than might occur. As
the rain does begin later this afternoon and into early this
evening, cig heights are expected to drop to 3 kft or less. As the
rain gets steadier, the vis will drop to around 5SM at all sites.
The pcpn will continue during the evening, but then end from
northwest to eastward at midnight or later. Should end at PIA
first and then last at CMI. Will keep fog in the forecast, based
on light winds and some low level moisture. Winds will be east to
southeasterly at 12kts or less during the day, but then become
light and variable through the rest of the period tonight.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Auten
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1254 PM CDT THU MAR 19 2015
.AVIATION...
SOME LINGERING CIGS BELOW 030 WILL KEEP MVFR CONDITIONS AROUND
SOME AIRPORTS EARLY THIS AFTERNOON...HOWEVER MOST LOCATIONS SHOULD
SEE THE LOWER CLOUD DECKS SCATTER OUT. VISIBLE SATELLITE IMAGERY
INDICATED MODERATE TO TOWERING CUMULUS CLOUDS...AND RADAR
INDICATED A FEW SHRA WERE DEVELOPING. THESE SHRA ARE EXPECTED TO
REMAIN ISOLATED IN MOST LOCATIONS...BUT A FEW AIRPORTS COULD HAVE
SOME BRIEF IMPACTS WITH CIGS AND LOWERED VSBYS. THE MAIN CONCERN
IS FOR LOW STRATUS AND FOG LATE TONIGHT INTO FRIDAY MORNING WHICH
APPEARS LIKELY...AND HAVE ADDED LIFR CONDITIONS TO THE 18Z TAFS.
22/TD
&&
.PREV DISCUSSION... /ISSUED 1014 AM CDT THU MAR 19 2015/
UPDATE...
BASED ON RADAR TRENDS AND THE 12Z SOUNDING HAVE LOWERED POPS
ACROSS THE AREA TO SLIGHT CHANCE...AND COMPLETELY REMOVED THE
MENTION OF RAIN FROM THE FORECAST FOR TONIGHT AND TOMORROW
MORNING. HAVE ALSO INCREASED THE FOG COVERAGE FOR TONIGHT...AS
LIGHT BOUNDARY LAYER WINDS AND A HIGH DEWPOINT AIRMASS CREATE
FAVORABLE CONDITIONS FOR FOG TO FORM. SIMILAR CONDITIONS ARE
EXPECTED FOR TOMORROW NIGHT. TEMPERATURES ARE ON TRACK AT MOST
LOCATIONS. HOWEVER...CONDITIONS ARE WARMING FASTER THAN
ANTICIPATED ON THE MISSISSIPPI GULF COAST. EXPECT TO SEE A
SEABREEZE FORM BY EARLY AFTERNOON...WHICH SHOULD KEEP TEMPERATURES
MORE STEADY ALONG THE COAST IN THE AFTERNOON HOURS. 32
PREV DISCUSSION... /ISSUED 415 AM CDT THU MAR 19 2015/
SHORT TERM...
A WARM AND MUGGY NIGHT WILL GIVE WAY TO ANOTHER WARM SPRING DAY
FOR THE FORECAST AREA TODAY AS A FRONTAL BOUNDARY STALLS OVER THE
FORECAST AREA. A FEW SHOWERS HAVE DEVELOPED THIS MORNING ALONG
THIS FRONTAL BOUNDARY AND THIS COULD SERVE AS A FOCUS FOR SOME
SHOWER DEVELOPMENT THROUGHOUT THE DAY AS TEMPERATURES ARE EXPECTED
TO CLIMB INTO THE LOWER 80S. WITH THIS BOUNDARY IN PLACE AND AMPLE
MOISTURE IN PLACE...A FEW SHOWERS AND MAYBE EVEN A THUNDERSTORM
COULD DEVELOP THIS AFTERNOON. SOME OF THE SHORT RANGE MODELS THE
HI-RES ARW AND NMM...AND EVEN THE HRRR SHOW ON AND OFF SHOWERS
THROUGHOUT THE DAY WITH MORE ACTIVITY IN THE AFTERNOON MAINLY
NORTH OF LAKE PONTCHARTRAIN. HAVE CARRIED ONLY SLIGHT CHANCE POPS
BUT WE COULD SEE AN UPDATE AT SOME POINT TODAY IF SHOWERS BECOME
MORE NUMEROUS. OVERALL IT SHOULD BE A RELATIVELY QUIET DAY AND
AGAIN FOR FRIDAY. 13/MH
LONG TERM...
THE NEXT ORGANIZED CHANCE FOR RAIN LOOKS TO COME THIS WEEKEND
BEGINNING SATURDAY MORNING WITH THE BULK OF THE PRECIPITATION
OCCURRING SATURDAY NIGHT INTO SUNDAY MORNING. A FAIRLY STRONG
SOUTHERN STREAM UPPER LEVEL LOW WILL BEGIN TO PUSH INTO TEXAS FROM
NORTHERN MEXICO AND THIS ENERGY WILL MOVE OVER THE FORECAST AREA
OVER THE WEEKEND. THE PREVIOUS FORECAST LOOKS TO BE ON TRACK AS
THIS SYSTEM WILL BRING RAIN AND SOME THUNDERSTORMS TO THE REGION.
SOME OF THESE SHOWERS AND STORMS COULD BE DECENT RAIN PRODUCERS AS
DEEP MOISTURE AND THE DEPTH OF THE WARM CLOUD LAYERS SHOULD ALLOW
FOR PERIODS OF HEAVY RAIN SATURDAY AND SUNDAY. RIGHT NOW THIS DOES
NOT LOOK LIKE A SEVERE WEATHER SETUP FOR THE AREA. HAVE INCREASED
RAIN CHANCES FOR THE ENTIRE AREA AND HAVE PUSHED INTO THE
CATEGORICAL RANGE FOR AREAS ALONG AN NORTH OF LAKE PONTCHARTRAIN
FOR SATURDAY NIGHT. THE SYSTEM WILL PUSH THROUGH ON SUNDAY AND WE
WILL STILL HAVE SOME LINGERING SHOWERS ON SUNDAY. THE UPPER LOW
MOVES OFF TO THE EAST ON MONDAY AS WE DRY OUT AND HIGH PRESSURE
MOVES INTO THE AREA. TEMPERATURES WILL COOL BACK TO MORE NORMAL
READINGS IN THE LOWER 70S FOR MONDAY AND TUESDAY...AND OVERNIGHT
LOWS WILL BE NEAR AVERAGE IN THE 50S. A FAIRLY STRONG MID AND
UPPER LEVEL RIDGE WILL DOMINATE ON TUESDAY AND WEDNESDAY...AND THE
STRONG SUBSIDENCE ALOFT WILL KEEP CLEAR SKIES IN PLACE ACROSS THE
REGION 13/MH
AVIATION...
CURRENTLY MAJORITY OF THE TERMINALS ARE STILL
EXPERIENCING VFR CONDITIONS BUT THIS MAY CHANGE DURING THE EARLY
MORNING HRS. MVFR AND TEMPO IFR CIGS AND VSBYS COULD DEVELOP.
CONDITIONS SHOULD THEN RETURN TO VFR SHORTLY AFTER SUNRISE. /CAB/
MARINE...
OVER THE NEXT 4 DAYS LOOK FOR BENIGN CONDITIONS TO DOMINATE THE
COASTAL WATERS WITH VARIABLE WINDS OF 10 KNOTS OR LESS EXPECTED AS
A BROAD AREA OF HIGH PRESSURE REMAINS PARKED OVER THE NORTHERN
GULF OF MEXICO AND A WEAK STALLED BNDRY LIES JUST NORTH OF THE
COAST. SEAS WILL GENERALLY RANGE FROM 1 TO 3 FEET...AND DO NOT
EXPECT ANY SIGNIFICANT MARINE IMPACTS DURING THIS PERIOD. THINGS
SHOULD FINALLY CHANGE LATE SUNDAY AS A SFC LOW MOVES ACROSS THE
REGION AND DRAGS THE FRONT SOUTH LEADING TO MODERATE OFFSHORE
WINDS SUN NIGHT AND INTO NEXT WEEK. /CAB/
DECISION SUPPORT...
DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 78 61 80 63 / 20 20 40 40
BTR 81 62 82 64 / 20 20 30 40
ASD 80 63 81 65 / 20 10 30 30
MSY 80 63 80 65 / 20 10 20 20
GPT 77 63 77 64 / 20 10 30 20
PQL 80 62 79 64 / 20 10 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
347 PM CDT Thu Mar 19 2015
.SHORT TERM: (Through Late Tonight)
Issued at 342 PM CDT Thu Mar 19 2015
The combination of weak mid level frontogenesis, weak low-level
convergence, and weak large scale ascent having been driving a band
of rain from eastern KS across northern MO into west central IL for
much of the afternoon. The band has managed to stay just north of
Columbia for much of the day. Present indications are that as the
attendant upstream shortwave migrates eastward this evening, the
western portion of the band will sink a bit south and impact areas
slight further south with likely or higher pops through mid-evening
persisting in the north. Later tonight the RAP and HRRR have been
very persistent for the last 4+ runs indicating another pocket of
rain will move along and just north of I-44 moving into central MO
around 05z and exiting the CWA by 10z. This appears to be in
response to mid-level convergence and frontogenesis and looks quite
reasonable, thus I have introduced some high chance to likely pops.
Otherwise clouds/stratus will hang tuf with clearing across parts of
central MO in the predawn hours, probably allowing for some fog.
Glass
.LONG TERM: (Friday through Next Thursday)
Issued at 342 PM CDT Thu Mar 19 2015
Mdls are in relatively good agreement thru the forecast period. A
cdfnt will drop into the region late Sat, bringing cooler temps for
Sun. Ahead of the fnt, have trended aoa the warmer guidance, which
is slightly warmer than the prev forecast.
Mdls prog a s/w within the nrn branch approaching the region on Mon.
Have kept PoPs low attm given the different mdl solns. For Tues, the
GFS/GEM mdls suggest any precip will remain further W, with a more
amplified flow and a more sly component of the LLJ. While the ECMWF
soln is a possibility, this does not seem likely attm. With
differences in sfc low track and strength of upper low, timing of
precip for Wed and beyond is more difficult. Have kept PoPs out of
the likely range for now given timing differences. However, it seems
that precip will be likely sometime between Tues night and Thurs
morning. Hopefully, timing will improve with future mdl cycles.
Temps are expected to remain near or above seasonal average.
Tilly
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1242 PM CDT Thu Mar 19 2015
In general, all terminals should see deteriorating flight conditions
from the afternoon into the evening. IFR should become dominate at
KCOU this afternoon, with IFR at KUIN this evening,and the St.
Louis area near 06z. Rainfall through this afternoon is expected
to remain predominately from west central MO into west central IL
with KCOU on the southern periphery and KUIN on the northern edge.
This rain area should move east and settle slowly south this
evening with drizzle and light rain become more predominate from
late evening into overnight. Stratus/cigs will also be slow to
clear and improve with KCOU/KUIN clearing on Friday morning and
the St. Louis area early Friday afternoon.
Specifics for KSTL:
Flight conditions expected to lower to MVFR this afternoon however
rain should remain just to the north. Light rain/drizzle expected to
settle in early this evening with continual lowering of cigs/vsbys
and IFR flight conditions around 06z. Stratus/cigs will be slow
to clear with clearing not expected until early Friday afternoon.
Glass
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 40 63 44 73 / 60 5 0 0
Quincy 36 59 42 68 / 70 0 0 0
Columbia 37 63 43 73 / 60 5 0 0
Jefferson City 37 63 42 74 / 60 5 0 0
Salem 41 57 43 69 / 50 10 0 0
Farmington 39 60 42 71 / 50 10 0 0
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
321 PM CDT THU MAR 19 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 257 PM CDT THU MAR 19 2015
SNOW ACROSS NORTHERN NORTH DAKOTA TONIGHT HIGHLIGHTS THE SHORT
TERM FORECAST.
THE LOW STRATUS FIELD ACROSS WESTERN AND CENTRAL NORTH DAKOTA
WILL CONTINUE TO ERODE FROM WEST TO EAST THROUGH THE REMAINDER OF
THE AFTERNOON AND EARLY EVENING GIVEN THE LATEST VISIBLE SATELLITE
TRENDS AND 16-18 UTC HRRR ITERATIONS. THEREAFTER...A RAPIDLY
PROPAGATING CLIPPER SYSTEM WILL ENTER NORTHWESTERN NORTH DAKOTA
EARLY FRIDAY MORNING...EXITING INTO NORTH CENTRAL SOUTH DAKOTA BY
18 UTC. A BAND OF LIGHT TO MODERATE SNOW WILL DEVELOP NORTH OF THE
SURFACE LOW TRACK ACROSS NORTH CENTRAL NORTH DAKOTA IN CONJUNCTION
WITH THE ARRIVAL OF A COLD FRONT INTO NORTHERN NORTH DAKOTA. THE
GREATEST SNOWFALL TOTALS OF TWO TO THREE INCHES ARE FORECAST FOR
THE TURTLE MOUNTAINS...QUICKLY DECREASING TO THE SOUTH AND WEST.
IN THE WARM SECTOR OF THE CLIPPER ACROSS SOUTHERN NORTH
DAKOTA...HIGHS IN THE LOWER 60S ARE POSSIBLE...NEAR THE WARMER
EDGE OF THE 12 UTC SUITE...GIVEN THE BIAS TO BE TOO COLD SO FAR IN
A WELL MIXED ENVIRONMENT WITH GOOD INSOLATION THIS MONTH.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 320 PM CDT THU MAR 19 2015
SEVERAL PERIODS OF ACCUMULATING SNOW ARE POSSIBLE SATURDAY THROUGH
WEDNESDAY.
AN ACTIVE WEATHER PATTERN IS SETTING UP FOR WESTERN AND CENTRAL
NORTH DAKOTA THIS WEEKEND THROUGH MID-WEEK.
THE FIRST STORM...AND POTENTIAL FOR WIDESPREAD ACCUMULATING SNOW...
WILL ARRIVE LATE SATURDAY AFTERNOON AND REMAIN THROUGH LATE SUNDAY
NIGHT. UPSLOPE FLOW...POTENT LEE CYCLOGENESIS AND FAVORABLE UPPER
LEVEL JET DYNAMICS (RIGHT ENTRANCE REGION OF A AN 80 KNOT JET)
COULD PRODUCE WIDESPREAD MODERATE SNOWFALL. THE MAIN AXIS OF
FRONTOGENESIS AND LIFT APPEARS TO BE SETTING UP MAINLY NORTH AND
EAST OF THE MISSOURI RIVER.
THE NEXT...AND POTENTIALLY STRONGER...STORM SYSTEM SHOULD IMPACT
THE REGION MONDAY NIGHT THROUGH WEDNESDAY AFTERNOON. THERE IS SOME
UNCERTAINTY IN THE EXACT TRACK OF THIS SYSTEM. THE 12 UTC GFS HAS
BEEN CONSISTENT IN SHOWING THE DEFORMATION ZONE ACROSS SOUTHERN
NORTH DAKOTA...WHILE THE 12 UTC ECMWF IS STILL SHOWING A FURTHER
NORTH SOLUTION. IT IS IMPORTANT TO NOTE THAT THE LATEST ECMWF RUN
IS TRENDING FURTHER SOUTH COMPARED TO PREVIOUS RUNS. SO IT DOES
APPEAR THAT AT LEAST SOME PORTION OF NORTH DAKOTA WILL BE
IMPACTED. HEAVY SNOWFALL IS POSSIBLE WITH THIS SYSTEM AS STRONG
FRONTOGENESIS...DEFORMATION BANDING...AND POTENTIAL TROW SET UP
ACROSS THE REGION. SURFACE TEMPERATURES WILL PLAY A LARGE ROLE IN
DETERMINING HOW MUCH SNOWFALL ACTUALLY ACCUMULATES. INDICATIONS
ARE THAT DURING THE DAYLIGHT HOURS TEMPERATURES ACROSS THE
NORTH DAKOTA WILL REMAIN WELL ABOVE FREEZING. DYNAMIC COOLING IN
SNOWBANDS WOULD LIKELY REDUCE AFTERNOON HEATING...BUT REGARDLESS
IT APPEARS THE MAJORITY OF ACCUMULATING SNOW WILL HAVE TO TAKE
PLACE OVERNIGHT.
NO HEADLINES WERE ISSUED WITH THIS FORECAST. IF TRENDS AND
CONFIDENCE CONTINUE TO INCREASE...HEADLINES ARE POSSIBLE THIS
WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 256 PM CDT THU MAR 19 2015
PRECIPITATION WAS MOVING OUT OF THE FORECAST AREA EARLY THIS
AFTERNOON. EXPECT SOME LINGERING FLURRIES AND MVFR CIGS EARLY IN THE
PERIOD...RISING TO VFR FROM WEST TO EAST AFT 20Z. A FEW SPRINKLES
AND BAND OF LOWER CIGS WILL MOVE SOUTHEAST FROM THE MONTANA BORDER
OVERNIGHT. BREEZY CONDITIONS IN THE SOUTHWEST PART OF THE STATE WILL
GIVE WAY TO LIGHT AND VARIABLE WINDS ACROSS ALL SITES BY EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AYD
LONG TERM...AJ
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS NORMAN OK
542 PM CDT THU MAR 19 2015
.AVIATION...
IFR CONDITIONS IN FOG AND LOW CEILINGS ARE EXPECTED TO LAST
THROUGH THE EVENING AND INTO EARLY FRIDAY. CONDITIONS WILL SLOWLY
IMPROVE NORTH TO SOUTH ACROSS OKLAHOMA LATER FRIDAY MORNING.
ISOLATED THUNDERSTORMS WILL END AROUND WICHITA FALLS BEFORE
200600. LIGHT RAIN WILL MOVE EAST OF OKLAHOMA CITY FRIDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 356 PM CDT THU MAR 19 2015/
DISCUSSION...
THE FIRST POINT OF CONCERN IS THE RISK OF THUNDERSTORMS INTO THIS
EVENING...MAINLY IN OUR TEXAS COUNTIES. THE RECENTLY-ISSUED
MESOSCALE DISCUSSION FROM SPC PROVIDES DETAILS ON THE SITUATION
THERE. IN ADDITION...THE HRRR MODEL SUPPORTS STORM DEVELOPMENT
FROM NOW INTO THE LATE EVENING...INCLUDING A FEW NON-SEVERE STORMS
NORTH ALMOST AS FAR AS I-40.
A COLD FRONT...WHICH IS PART OF THE REASON FOR THE RAIN AND
STORMS...WILL STRENGTHEN AND EDGE SOUTH THIS EVENING AND
OVERNIGHT...EVENTUALLY PUSHING THE MAIN PRECIPITATION AREA SOUTH.
HOWEVER...THE FRONT WILL NOT GET ALL THAT FAR INTO TEXAS...AND
SUFFICIENT MOISTURE/LIFT WILL REMAIN IN PLACE TO KEEP A CHANCE OF
RAIN IN OUR SOUTHERN COUNTIES WELL INTO THE WEEKEND.
ON TUESDAY...ANOTHER STORM SYSTEM WILL TAKE SHAPE...AND TUESDAY
SHOULD BE A WINDY DAY WITH A MODERATE TO STRONG CAPPING INVERSION.
THIS WILL HOLD DOWN THE CHANCES FOR STORMS UNTIL A COLD FRONT
ARRIVES LATE TUESDAY INTO WEDNESDAY. STORM CHANCES WILL RETURN
WITH THIS FRONT...ALTHOUGH IT WILL STILL HAVE THE CAP TO CONTEND
WITH.
BEYOND WEDNESDAY...MODELS DIVERGE QUITE A BIT...ALTHOUGH THE GFS
DOES NOT APPEAR TO HAVE A GOOD BACKING FROM ITS OWN ENSEMBLE.
SO...WE CAN PROBABLY SAFELY IGNORE THE SNOWFALL THAT IT GENERATES
ON THURSDAY AND FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 43 66 47 70 / 70 10 0 10
HOBART OK 42 62 46 70 / 70 10 0 10
WICHITA FALLS TX 49 62 50 68 / 90 20 10 20
GAGE OK 37 70 43 74 / 50 10 0 0
PONCA CITY OK 39 71 44 73 / 50 10 0 0
DURANT OK 52 62 53 66 / 90 40 20 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
26/09/09
AREA FORECAST DISCUSSION
NWS NORMAN OK
356 PM CDT THU MAR 19 2015
.DISCUSSION...
THE FIRST POINT OF CONCERN IS THE RISK OF THUNDERSTORMS INTO THIS
EVENING...MAINLY IN OUR TEXAS COUNTIES. THE RECENTLY-ISSUED
MESOSCALE DISCUSSION FROM SPC PROVIDES DETAILS ON THE SITUATION
THERE. IN ADDITION...THE HRRR MODEL SUPPORTS STORM DEVELOPMENT
FROM NOW INTO THE LATE EVENING...INCLUDING A FEW NON-SEVERE STORMS
NORTH ALMOST AS FAR AS I-40.
A COLD FRONT...WHICH IS PART OF THE REASON FOR THE RAIN AND
STORMS...WILL STRENGTHEN AND EDGE SOUTH THIS EVENING AND
OVERNIGHT...EVENTUALLY PUSHING THE MAIN PRECIPITATION AREA SOUTH.
HOWEVER...THE FRONT WILL NOT GET ALL THAT FAR INTO TEXAS...AND
SUFFICIENT MOISTURE/LIFT WILL REMAIN IN PLACE TO KEEP A CHANCE OF
RAIN IN OUR SOUTHERN COUNTIES WELL INTO THE WEEKEND.
ON TUESDAY...ANOTHER STORM SYSTEM WILL TAKE SHAPE...AND TUESDAY
SHOULD BE A WINDY DAY WITH A MODERATE TO STRONG CAPPING INVERSION.
THIS WILL HOLD DOWN THE CHANCES FOR STORMS UNTIL A COLD FRONT
ARRIVES LATE TUESDAY INTO WEDNESDAY. STORM CHANCES WILL RETURN
WITH THIS FRONT...ALTHOUGH IT WILL STILL HAVE THE CAP TO CONTEND
WITH.
BEYOND WEDNESDAY...MODELS DIVERGE QUITE A BIT...ALTHOUGH THE GFS
DOES NOT APPEAR TO HAVE A GOOD BACKING FROM ITS OWN ENSEMBLE.
SO...WE CAN PROBABLY SAFELY IGNORE THE SNOWFALL THAT IT GENERATES
ON THURSDAY AND FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 43 66 47 70 / 70 10 0 10
HOBART OK 42 62 46 70 / 70 10 0 10
WICHITA FALLS TX 49 62 50 68 / 90 20 10 20
GAGE OK 37 70 43 74 / 50 10 0 0
PONCA CITY OK 39 71 44 73 / 50 10 0 0
DURANT OK 52 62 53 66 / 90 40 20 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
84/23
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
644 PM EDT THU MAR 19 2015
.SYNOPSIS...
ONE LOW PRESSURE SYSTEM WILL CROSS TO THE COAST FROM THE TENNESSEE VALLEY
AND THEN HEAD NORTH ALONG THE COAST FRIDAY. A SECOND LOW WILL HEAD
EASTWARD ALONG THE OHIO VALLEY ON FRIDAY WITH ITS ASSOCIATED COLD
FRONT SWEEPING ACROSS THE AREA. HIGH PRESSURE WILL BUILDS INTO THE
AREA FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 630 PM EDT THURSDAY...
MADE SOME ADJUSTMENTS TO POPS/WX TYPE/TEMPS AND SNOW AMOUNTS
THROUGH EVENING. HRRR FROM 21Z SEEMS TO BE HANDLING LOCATION OF
PRECIP FAIRLY WELL. STILL GETTING A MIX OF SLEET/RAIN HERE WITH
SNOW FURTHER NORTH INTO THE HIGHER ELEVATIONS. MADE ADJUSTMENTS TO
THE PTYPE BASED ON THE RAP AND WET BULB...WHICH GIVES MORE SNOW TO
THE HIGHER ELEVATIONS NORTH OF LWB AND LEXINGTON. SOME AREAS COULD
SEE AN INCH OR TWO OF SNOW...BUT OVERALL THE SNOW AMOUNTS WILL BE
LIMITED BY WET/MILD GROUND. MOST LOCATIONS WILL HAVE MAINLY RAIN
OVERNIGHT...WITH SOME PERIODS WHERE NOTHING IS FALLING FROM THE
SKY BETWEEN UPPER VORTS. THERE IS A TIGHT GRADIENT IN TERMS OF
DEWPOINTS IN THE NORTH...WHERE CHO/SHD HAVE DEWPOINTS IN THE 20S
WHERE PRECIP HAS HELD OFF TO MID 30S AROUND LYH...SO THERE WILL
BE WET-BULBING EFFECTS NORTH OF INTERSTATE 64 INTO THE BLUE RIDGE
NORTH OF ROANOKE WHERE SNOW AND SLEET OCCUR EARLY.
ROADS SHOULD STAY WET GIVEN MILD TEMPERATURES OF THE
GROUND...THOUGH OVER THE HIGHER SECONDARY ROADS OF GREENBRIER
COUNTY EAST TO ROCKBRIDGE...A COATING MAY OCCUR.
PREVIOUS VALID DISCUSSION...
LOW PRESSURE WAS PROGRESSING INTO EASTERN TENNESSEE ALL WHILE A
PRECIPITATION ASSOCIATED WITH ITS WARM CONVEYOR BELT SPREAD ACROSS
THE REGION.
THROUGH THE OVERNIGHT...BOTH TEMPERATURES AND DEW POINTS WILL SLOWLY
RISE SO THAT LOW TEMPERATURES SHOULD OCCUR AROUND SUNSET...EXCEPT
FOR THOSE AREAS IN THE NORTH THAT WILL START TO COOL AS THE
PRECIPITATION INCREASES IN INTENSITY. LOWS WILL RANGE FROM THE
LOW TO MID 30S ACROSS THE MOUNTAINS TO THE UPPER 30S TO LOWER 40S
ACROSS THE PIEDMONT.
BY FRIDAY MORNING...THE TENNESSEE LOW WILL BE NEAR THE
COAST...AND STARTED ITS PROGRESSION NORTHEAST.
CONCURRENTLY...ANOTHER AREA OF LOW PRESSURE WILL BE PROGRESSING
EASTWARD THROUGH THE OHIO VALLEY. ITS ASSOCIATED COLD FRONT WILL
PROGRESS ACROSS THE AREA FRIDAY AFTERNOON. UNTIL THAT
TIME...EXPECT THE COLD AIR DAMMING WEDGE TO HOLD FAST ACROSS THE
REGION...WITH PLENTY OF CLOUD COVER. PRECIPITATION WILL GRADUALLY
DECREASE IN COVERAGE ACROSS THE AREA FRIDAY MORNING WITH THE
DEPARTURE OF THE COASTAL LOW. HOWEVER...LOOK FOR A RESURGENCE IN
THE WEST AS THE COLD FRONT CROSSES THE AREA. FRIDAY
AFTERNOON...PRECIPITATION IS EXPECTED TO BE LACKING EAST OF THE
BLUE RIDGE AS DOWNSLOPE WINDS SUPPRESS THE ACTIVITY. TEMPERATURES
WILL BE SLOW TO RISE WHILE THE COLD AIR DAMMING IS STILL IN PLACE.
IRONICALLY...IT WILL TAKE THE COLD FRONT TO HELP MIX THE LOWER
ATMOSPHERE AND START TO THIN OUT THE CLOUD COVER A BIT IN THE EAST
TO HELP TEMPERATURES RISE ON FRIDAY. HIGHS ARE EXPECTED TO RANGE
FROM THE UPPER 40S TO AROUND 50 ACROSS THE MOUNTAINS...TO THE 50S
ACROSS THE PIEDMONT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 310 PM EDT THURSDAY...
CONFLUENT FLOW ALOFT AND DRIER AIR BEHIND THE COLD FRONT FRIDAY AND
SATURDAY. ANY PRECIPITATION THAT IS LEFT OVER LATE IN THE DAY ON
FRIDAY WILL QUICKLY DISSIPATE FRIDAY EVENING.
A COLD FRONT WILL COME THROUGH SATURDAY. NO PRECIPITATION IS
EXPECTED ALONG THIS BOUNDARY.
HAVE PROBABILITY OF PRECIPITATION MOVING BACK INTO THE SOUTHERN
COUNTY WARNING AREA ON SUNDAY WITH THE APPROACH OF A WEAKENING
SOUTHERN STREAM SHORT WAVE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 1205 PM EDT THURSDAY...
SPLIT FLOW WITH BROAD EASTERN UNITED STATES TROF ON MONDAY
TRANSITIONS TO A WESTERN TROF AND RIDGING OVER THE EAST ON WEDNESDAY
AND THURSDAY. SOUTHERN STREAM SYSTEM REMAINS SUPPRESSED ON SUNDAY
NIGHT AND MONDAY WITH A MAJORITY OF THE HEAVIER PRECIPITATION ACROSS
THE SOUTHEAST UNITED STATES. SOME WINTER PRECIPITATION MAY BE
POSSIBLE ON THE NORTHERN FRINGE OF THIS SYSTEM. THIS WILL DEPEND ON
HOW FAR COLDER AIR AND HIGH PRESSURE WEDGES DOWN INTO THE MID
ATLANTIC REGION. CENTER OF HIGH PRESSURE WILL BE IN A FAVORABLE
POSITION FOR A WEDGE ON MONDAY. CAD WILL ALSO BE ENHANCED BY INVERTED
TROFFING WEST OF THE APPALACHIANS.
SOME SHORT WAVE ENERGY COMING THROUGH THE NORTHERN STREAM ON TUESDAY
MAY IMPACT THE FORECAST AREA. THERE WILL ALSO BE A WARMING TREND ON
WEDNESDAY AND THURSDAY IN ADVANCE OF THE NEXT SIGNIFICANT COLD
FRONT. ECMWF SHOWED SOME INDICATIONS OF A CHANCE OF PRECIPITATION IN
ASSOCIATION WITH A WARM FRONT ON WEDNESDAY. SURFACE HIGH PRESSURE
MOVES OFFSHORE BY WEDNESDAY WITH DEEP MOISTURE COMING OUT OF THE
GULF AHEAD OF THE COLD FRONT.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 145 PM EDT THURSDAY...
PRECIPITATION SHIELD OF RAIN AND SNOW CONTINUES TO SPREAD ACROSS
THE AREA. ISOLATED SLEET HAS BEEN NOTED NEAR THE VA/NC BORDER.
CIGS WILL CONTINUE TO TREND TO MVFR LEVELS AS THE AFTERNOON
PROGRESSES ALONG WITH MVFR/VFR VSBYS IN ASSOCIATION WITH THE
PRECIPITATION. PRECIPITATION WILL INCREASE THROUGH THE NIGHT WITH
A TREND TOWARDS MORE RAIN THAN SNOW...ALTHOUGH SNOW WILL STILL BE
POSSIBLE AT HIGHER ELEVATIONS...ESPECIALLY ALONG AND NORTH OF I-64.
CIGS AND VSBYS WILL TREND LOWER WITH MANY LOCATIONS WITH IFR CIGS
AND VSBYS BY 12Z/8AM FRIDAY.
THERE WILL BE A DECREASE IN THE PRECIPITATION COVERAGE FRIDAY
MORNING AS A COASTAL LOW LIFTS NORTHEAST AWAY FROM THE AREA.
HOWEVER...ANOTHER LOW MOVING THROUGH THE OHIO VALLEY WILL BRING
ITS ASSOCIATED PRECIPITATION TOWARDS THE REGION BY MID-DAY
FRIDAY. ANTICIPATE AREAS ALONG AND EAST OF THE BLUE RIDGE TO TREND
TO LOW END VFR. MVFR CONDITIONS WILL BE MORE COMMON ACROSS THE
MOUNTAINS.
EXTENDED FORECAST...COLD FRONT MOVES THROUGH THE REGION ON FRIDAY
IMPROVING CONDITIONS TO VFR AT ROA/LYH/DAN. CLOUDS MAY LINGER IN
THE MOUNTAINS...IMPACTING BLF/LWB/BCB...WITH POTENTIAL FOR MVFR
THROUGH MUCH OF FRIDAY. HIGH PRESSURE AND RETURN TO MAINLY VFR
CONDITIONS EXPECTED FOR THE WEEKEND AND EARLY NEXT WEEK.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...DS
NEAR TERM...DS/WP
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...DS