Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/20/14
AREA FORECAST DISCUSSION
NWS TUCSON AZ
855 AM MST TUE FEB 18 2014
.SYNOPSIS...ONE MORE DAY OF NEAR RECORD HIGH TEMPERATURES. A WEAK
WEATHER SYSTEM PASSING NORTH OF THE AREA WILL BRING GUSTY AFTERNOON
WINDS WEDNESDAY. OTHERWISE...EXPECT A GRADUAL COOLING TREND THIS
WEEK BUT TEMPERATURES WILL REMAIN ABOVE AVERAGE INTO AT LEAST EARLY
NEXT WEEK.
&&
.DISCUSSION...WATER VAPOR IMAGERY SHOWS A WEAK SHORTWAVE SYSTEM
CURRENTLY MOVING THROUGH SE COLORADO AND NE NEW MEXICO AT THIS TIME.
MEANWHILE...NEARLY ZONAL FLOW WILL PERSISTS TODAY ACROSS THE DESERT
SOUTHWEST WITH ANOTHER TROUGH MOVING BY TO OUR NORTH OVER THE FOUR
CORNERS REGION LATE WEDNESDAY AFTERNOON. THIS SYSTEM WILL BRING AN
INCREASE IN THE WINDS WEDNESDAY AFTERNOON MAINLY ACROSS THE FAR
EASTERN ZONES...SPECIFICALLY ALONG THE NEW MEXICO BORDER. THAT
SAID...A FIRE WEATHER WATCH IS IN EFFECT FOR THIS AREA FOR WEDNESDAY
AFTERNOON AND EARLY EVENING (SEE THE FIRE WEATHER SECTION BELOW).
AS OF 15Z (8 AM MST)...TEMPERATURES ACROSS THE REGION RANGED FROM
THE UPPER 40S TO THE MID 50S AND THESE READINGS APPEAR TO BE ON
TRACK WITH THE ANTICIPATED HIGH TEMPERATURES FOR THIS AFTERNOON.
THEREFORE...NO CHANGES ARE PLANNED AT THIS TIME...BUT WILL CONTINUE
TO MONITOR SURFACE OBSERVATIONS AND WILL MAKE CHANGES IF NEEDED.
FOR DETAILS REGARDING THE FORECAST BEYOND TODAY...PLEASE REFER TO
THE PREVIOUS DISCUSSION BELOW.
&&
.AVIATION...VALID THRU 19/18Z. SCT-BKN ABV 20K FT. NORMAL DIURNAL
WIND TRENDS LESS THAN 10 KTS...EXCEPT BECMG SW 8-14KT AFT 18/20Z
THRU 19/02Z MAINLY SE OF KTUS. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.
&&
.FIRE WEATHER...ABOVE AVERAGE TEMPERATURES AND DRY CONDITIONS INTO
THIS COMING WEEKEND. SOME LOCALLY BREEZY SPOTS THIS AFTERNOON...THEN
AN UPPER LEVEL TROF IS EXPECTED TO SLIDE SE ACROSS THE 4-CORNERS
AREA LATE WEDNESDAY GENERATING INCREASED WESTERLY WINDS WEDNESDAY.
THE STRONGEST WINDS WILL BE ACROSS EASTERN AREAS AND WIND PRONE
LOCATIONS ALONG THE EASTERN SLOPES. GENERALLY EXPECTING 15-25 MPH 20
FT WINDS ACROSS THOSE LOCATIONS WITH AREAS OF RED FLAG CONDITIONS
POSSIBLE ACROSS EASTERN COCHISE...SOUTHERN GREENLEE AND SOUTHEAST
GRAHAM COUNTIES AS PER CURRENT FIRE WEATHER WATCH FOR WEDNESDAY.
&&
.PREVIOUS DISCUSSION...ZONAL FLOW DIRTIED UP WITH CIRRUS LEVEL
MOISTURE AT TIMES...BUT OTHERWISE RATHER DRY. PRECIPITABLE WATER
UNDER 1/3 OF AN INCH AND SURFACE DEWPTS IN THE TEENS AND 20S. A
GRADUAL COOLING TREND AS HEIGHTS AND THICKNESSES RECEDE EARLY THIS
WEEK...BUT STILL WARM ENOUGH FOR ONE MORE DAY NEAR RECORDS IN A
COUPLE OF LOCATIONS.
LATEST HRRR STREAMLINE TRENDS HINTING AT MODEST GRADIENT ENHANCEMENT
AS EARLY AS MID TO LATE AFTERNOON TODAY. AN IMPULSE PASSING NORTH OF
THE AREA WEDNESDAY WILL SEE THE STRONGEST GRADIENT IN OUR PART OF
THE STATE FOR WEDNESDAY AFTERNOON. BELOW ADVISORY LEVELS BUT SOME
CONCERNS FOR THE FIRE WEATHER FORECAST AS ADDRESSED BELOW.
AN EVEN HIGHER LATITUDE RESOLUTION FOR THE WEEKEND SYSTEM AS THE
REBUILDING EASTERN PACIFIC RIDGE NOSES IN TO CONTINUE TO KEEP US DRY
AND UNSEASONABLY WARM.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...FIRE WEATHER WATCH IN EFFECT
WEDNESDAY AFTERNOON AND EVENING...FOR SOUTHERN PORTIONS OF FIRE
WEATHER ZONES 146 AND EASTERN PORTIONS OF FIRE WEATHER ZONE 148.
&&
$$
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CURRENT DISCUSSION...MOLLERE
PREVIOUS DISCUSSION...MEYER/RASMUSSEN
AREA FORECAST DISCUSSION
NWS TUCSON AZ
230 AM MST TUE FEB 18 2014
.SYNOPSIS...ONE MORE DAY OF NEAR RECORD HIGH TEMPERATURES. A WEAK
WEATHER SYSTEM PASSING NORTH OF THE AREA WILL BRING GUSTY AFTERNOON
WINDS WEDNESDAY. OTHERWISE...EXPECT A GRADUAL COOLING TREND THIS
WEEK BUT TEMPERATURES WILL REMAIN ABOVE AVERAGE INTO AT LEAST EARLY
NEXT WEEK.
&&
.DISCUSSION...ZONAL FLOW DIRTIED UP WITH CIRRUS LEVEL MOISTURE AT
TIMES...BUT OTHERWISE RATHER DRY. PRECIPITABLE WATER UNDER 1/3 OF AN
INCH AND SURFACE DEWPTS IN THE TEENS AND 20S. A GRADUAL COOLING
TREND AS HEIGHTS AND THICKNESSES RECEDE EARLY THIS WEEK...BUT STILL
WARM ENOUGH FOR ONE MORE DAY NEAR RECORDS IN A COUPLE OF LOCATIONS.
LATEST HRRR STREAMLINE TRENDS HINTING AT MODEST GRADIENT ENHANCEMENT
AS EARLY AS MID TO LATE AFTERNOON TODAY. AN IMPULSE PASSING NORTH OF
THE AREA WEDNESDAY WILL SEE THE STRONGEST GRADIENT IN OUR PART OF
THE STATE FOR WEDNESDAY AFTERNOON. BELOW ADVISORY LEVELS BUT SOME
CONCERNS FOR THE FIRE WEATHER FORECAST AS ADDRESSED BELOW.
AN EVEN HIGHER LATITUDE RESOLUTION FOR THE WEEKEND SYSTEM AS THE
REBUILDING EASTERN PACIFIC RIDGE NOSES IN TO CONTINUE TO KEEP US DRY
AND UNSEASONABLY WARM.
&&
.AVIATION...VALID THRU 19/12Z. SCT-BKN ABV 20K FT. NORMAL DIURNAL
WIND TRENDS LESS THAN 10 KTS...EXCEPT BECMG SW 8-14KT AFT 18/20Z
THRU 19/02Z MAINLY SE OF KTUS. AVIATION DISCUSSION NOT UPDATED FOR
TAF AMENDMENTS.
&&
.FIRE WEATHER...ABOVE AVERAGE TEMPERATURES AND DRY CONDITIONS INTO
THIS COMING WEEKEND. SOME LOCALLY BREEZY SPOTS THIS AFTERNOON...THEN
AN UPPER LEVEL TROF IS EXPECTED TO SLIDE SE ACROSS THE 4-CORNERS
AREA LATE WEDNESDAY GENERATING INCREASED WESTERLY WINDS WEDNESDAY.
THE STRONGEST WINDS WILL BE ACROSS EASTERN AREAS AND WIND PRONE
LOCATIONS ALONG THE EASTERN SLOPES. GENERALLY EXPECTING 15-25 MPH
20 FT WINDS ACROSS THOSE LOCATIONS WITH AREAS OF RED FLAG CONDITIONS
POSSIBLE ACROSS EASTERN COCHISE...SOUTHERN GREENLEE AND SOUTHEAST
GRAHAM COUNTIES AS PER CURRENT FIRE WEATHER WATCH FOR WEDNESDAY.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...FIRE WEATHER WATCH IN EFFECT
WEDNESDAY AFTERNOON AND EVENING...FOR SOUTHERN PORTIONS OF FIRE
WEATHER ZONES 146 AND EASTERN PORTIONS OF FIRE WEATHER ZONE 148.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
MEYER/RASMUSSEN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
858 PM MST WED FEB 19 2014
.UPDATE...
&&
.SHORT TERM...VERY CONVECTIVE ENVIRONMENT HAS DEVELOPED WITH
THUNDERSNOW OVER SOUTH DENVER WITH BRIEF 40-50DBZ ON 88D. PRECIP
HAS RAPIDLY CHANGED TO SNOW IN MOST LOCALES. LOOKS LIKE THE
RAP/HRRR WAS RIGHT ON AGAIN AND EVEN THE NAM HAS COME AROUND TO
SNOW ACCUM FURTHER WEST TOWARDS THE FRONT RANGE. MODELS ARE
PAINTING 3-6 INCHES OF SNOW OVER THE PALMER DIVIDE TONIGHT AND
LOOKS REASONABLE GIVEN LATEST TRENDS. HAVE ALREADY HOISTED AN
ADVISORY FOR ZONES 41..46 AS THESE LOOK TO BE THE AREAS TO GET THE
BRUNT OF THE SNOW WITH FAVORED NORTHERLY OROGRAPHIC FLOW. STRONG
QG ASCENT AND GOOD INSTABILITY ARE TILTING THE SCALES FOR MORE
SNOW. MIGHT NEED TO ADD ZONE 36 INTO THE ADVISORY AS WELL IF
CURRENT TRENDS CONTINUE.
.AVIATION...CIGS/VSBYS HAVE LOWERED RAPIDLY IN THE PAST HOUR WITH
EVEN THUNDERSNOW AT APA AND IFR CONDITIONS AT KDEN. BJC WILL SEE
LESS SNOW AS THEY ARE ON THE NORTHERN FRINGE OF THE MOISTURE AND
BETTER UPSLOPE FLOW. LATEST SNOWFALL LOOKS TO BE 1-2 INCHES AT
KDEN AND 2-3 INCHES AT APA. LESS THAN AN INCH AT BJC. CONDITIONS
WILL IMPROVE AFTER MIDNIGHT.
&&
.PREV DISCUSSION... /ISSUED 732 PM MST WED FEB 19 2014/
UPDATE...
SHORT TERM...COLD FRONT MOVING ACROSS THE CWA AS WINDS ON THE
PLAINS SHIFTING NORTH AND NORTHEAST AT 20-35KT. 88D SHOWING
REFLECTIVITY RAPIDLY DEVELOPING EARLY THIS EVENING PRETTY MUCH
LIKE THE RAP/HRRR HAVE BEEN SHOWING IN LATEST RUNS. JUST UPDATED
FORECASTS FOR LIKELY POPS FOR SNOW TONIGHT BUT OVERALL
ACCUMULATIONS STILL UNDER 2 INCHES. QG FIELDS HAVE BEEN SHOWING
STRONG UPWARD ASCENT AND GOOD INSTABILITY WITH THIS SYSTEM AND
APPEARS ABLE TO OVERCOME SOME OF THE DOWNSLOPE FLOW OFF THE FRONT
RANGE. GIVEN THE STRONG 3HR 5MB RISE INTO NEBRASKA PANHANDLE
EXPECT SOME NORTHEAST WINDS OVER SOUTHERN AND EASTERN PORTIONS OF
CWA. WILL MONITOR THIS EVENING IN CASE HIGHER SNOWFALL AMOUNTS ARE
NEEDED. THE RAP DID INDICATE HEAVIER AMOUNTS OVER THE PALMER
DIVIDE AND MAYBE NOT OUT OF THE QUESTION.
AVIATION...STRONG NORTHERLY WINDS HAVE DEVELOPED AT KDEN AND WILL
MOVE INTO BJC/APA DURING THE NEXT HOUR. EXPECT CEILINGS TO LOWER
AND PRECIP TO DEVELOP BETWEEN 03-04Z. MAYBE A BRIEF SHOT OF
RAIN/SNOW BUT SHOULD TURN TO ALL SNOW RATHER QUICKLY. MOISTURE AND
UPSLOPE LOOK BETTER THIS EVENING AND WILL BE SHOWING LOWER
CIGS/VSBYS THAN CURRENT IN TAFS. SNOWFALL ACCUM STILL SHOULD BE
LESS THAN AN INCH AT BJC/DEN AND POSSIBLE UP TO 2 INCHES AT APA
WITH FAVORED NORTHERLY FLOW THERE. TAF UPDATES COMING.
PREV DISCUSSION... /ISSUED 219 PM MST WED FEB 19 2014/
SHORT TERM...UPPER TROUGH AXIS OVER NRN UT/WRN WY THIS AFTN
WILL CONTINUE IT TRACK ACROSS NORTHERN COLORADO LATE THIS
AFTERNOON AND TONIGHT. MDT TO STG MID AND UPPER LEVEL QG ASCENT
OVER NORTHERN COLORADO THROUGH THIS EVENING...WITH THE TROF AXIS
ALONG THE EASTERN CO BORDER BY 12Z THURSDAY. COLD FRONT ASSOCIATED
WITH THE SYSTEM MOVING INTO NWRN CO AT THIS TIME. SHOULD SEE SNOW
INCREASE IN COVERAGE NORTH OF INTERSTATE 70 THIS AFTERNOON...WITH
MODERATE TO HEAVY SNOWFALL OVERNIGHT. THE SYSTEM IS UNSTABLE AS
WELL SO COULD SEE A LIGHTNING STRIKE OR TWO AS THE SYSTEM PASSES
OVER THE STATE SO MAY ADD ISOLD THUNDER TO THE MOUNTAIN GRIDS AS
WELL. I WILL LIKELY EXTEND THE WINTER WEATHER ADVISORY INTO
THURSDAY MORNING. ACROSS THE NORTHEAST PLAINS...THE FRONT WILL
MOVE THROUGH THE AREA BY MID EVENING...WITH A STRONG NORTHERLY
PUSH FOLLOWING FROPA. WL KEEP CHC POPS ALONG THE URBAN CORRIDOR.
BEST CHC OF SNOW WILL OCCUR ON OR AFTER FROPA WITH GOOD INSTBY
OVERHEAD AND PRETTY GOOD QG ASCENT AS WELL. BEST CHC FOR
ACCUMULATING SNOWFALL WILL BE FURTHER EAST. SNOW MAY NOT STICK
INITIALLY...BUT COULD BECOME MORE OF AN ISSUE TOWARD MIDNIGHT. IT
IS A FAIRLY SHORT SNOW EVENT...2 TO 4 HOURS...SO WL KEEP EXPECTED
ACCUMULATIONS 2 INCHES OR LESS. STRONG WINDS FOLLOWING THE FRONT
MAY ALSO PRODUCE AREAS OF BLOWING SNOW SO HAVE ADDED THE GRIDS AS
WELL. ON THURSDAY...AMS WILL DRY OUT SIGNIFICANTLY AS STRONG
SUBSIDENCE DEVELOPS. GOOD OROGRAPHIC COMPONENT IN THE MORNING SO
WL GO WITH SOME LIGHT SNOW...PRIMARILY ALONG WEST FACING SLOPES.
WL EXTEND THE WINTER WEATHER ADVISORY UNTIL NOON. ACROSS THE
NORTHEAST PLAINS...STRONG NW WINDS WITH BORA TYPE SET UP. WL KEEP
THE STRONGER GUSTS UNDER HIGH WIND CRITERIA BUT KEEP GUSTS TO 50
MPH OVER THE ZONES ADJACENT TO NEBRASKA/KANSAS BORDERS.
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...A NORTHWEST FLOW
ALOFT WILL BE OVER THE CENTRAL ROCKIES THROUGH SUNDAY. WINDY
CONDITIONS ARE EXPECTED THURSDAY NIGHT IN AND NEAR FOOTHILLS AS
MODELS ARE HINTING AT A MOUNTAIN WAVE FORMING. SOME DIFFERENCE WITH
THE DETAILS IN THE MODELS...SO FOR NOW WILL GO WITH GUSTS OF 60 TO
70 MPH...JUST BELOW HIGH WIND CRITERIA.
SNOW WILL INCREASE IN THE MOUNTAINS AS MOISTURE INCREASES AND
DEEPENS. EXPECT MOUNTAIN SNOW FROM THURSDAY NIGHT THROUGH SATURDAY
NIGHT. BEST AND DEEPEST MOISTURE OCCURS THURSDAY NIGHT THEN AGAIN ON
FRIDAY NIGHT AND SATURDAY. THE OROGRAPHIC LIFT WILL BE THE PRIMARY
FORCING...SO EXPECT MOST OF THE SNOW OVER THE MOUNTAINS WITH JUST
LIGHT AMOUNTS IN THE VALLEYS. MAY BE ENOUGH FOR A WINTER WEATHER
ADVISORY. WILL LET TONIGHT`S SYSTEM PLAY OUT BEFORE ISSUING ANYTHING
FOR THE NEXT ROUND OF SNOW.
FOR NORTHEAST COLORADO...FRIDAY WILL BE WINDY WITH MILD TEMPERATURES
AHEAD OF AN APPROACHING COLD FRONT. THIS FRONT WILL MOVE THROUGH
LATE FRIDAY OR SATURDAY. THIS SCENARIO IS SIMILAR TO THIS PAST
SATURDAY WHERE MODELS DISAGREED ON HOW FAR SOUTH THE FRONT WOULD
GET. THE ECMWF IS AGAIN SHOWING THE COLDER AIR BEING DEEPER AND
ARRIVING SOONER. SINCE ECMWF WAS THE MOST ACCURATE WILL BASE THE
FORECAST ON THIS. WENT AHEAD AND LOWERED TEMPERATURES INTO THE 30S
FOR NORTHEAST COLORADO. BY SATURDAY EVENING...COULD SEE SOME SNOW
MOVE ONTO THE PLAINS AS A SHORT WAVE TROUGH MOVES OVER NORTHERN
COLORADO AND WYOMING.
FLOW ALOFT WILL WEAKEN EARLY NEXT WEEK AS AN UPPER LEVEL RIDGE
BUILDS OVER THE GREAT BASIN. THIS WILL REDUCE THE CHANCE FOR SNOW IN
THE MOUNTAINS. SHORT WAVE TROUGHS EMBEDDED IN THE NORTHWEST FLOW
ALOFT WILL PASS TO THE NORTHEAST OF COLORADO. THE TROUGH ON MONDAY
WILL PUSH A COLD FRONT THROUGH THE AREA DURING THE DAY
MONDAY...HELPING TO REINFORCE THE COOLER AIR. EXPECT TEMPERATURES TO
REMAIN AT OR BELOW NORMAL EARLY NEXT WEEK. CAN`T RULE OUT SOME
MOUNTAIN SNOW...BUT WITH THE MAIN FLOW ALOFT NORTH AND EAST OF THE
STATE...ANY SNOW WILL BE LIGHT.
AVIATION...VFR CIGS/VSBYS THROUGH 02Z. NW WINDS WILL PICK UP AS
SFC LOW SHIFTS MORE SOUTH AND EAST AND WE GET INTO MORE OF THE
PRESSURE GRADIENT. FROPA SHOULD OCCUR IN THE 05-06Z WITH A BRIEF
PERIOD OF NELY SFC WINDS...THEN IT WILL SWITCH BACK TO NNW. STRONG
DYNAMICS ALOFT AND GOOD INSTABILITY WITH THE FROPA...SO SNOW MAY
SWITCH OVER FAIRLY FAST. COULD ALSO SEE A BRIEF PERIOD OF
THUNDERSNOW WITH THE FROPA. NOT CONFIDENT ENUF TO PUT IT IN THE
TAFS AT THIS TIME. CIGS WILL DROP TO BLO 5K FT AFTER 02Z. IF SOME
THUNDER MIXES IN WITH THE SNOW...THEN IFR CIGS/VSBYS POSSIBLE FOR
A BRIEF PERIOD. WINDOW FOR SNOWFALL WILL BE IN THE 2-4 HOUR TIME
FRAME...04-08Z. IMPROVING CIGS AFTER 09Z...WITH NWLY WINDS
INCREASING AFTER 15Z THURSDAY.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON MST THURSDAY FOR COZ031-033-
034.
WINTER WEATHER ADVISORY UNTIL 4 AM MST THURSDAY FOR COZ041-046.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM....MEIER
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
855 PM MST WED FEB 19 2014
.UPDATE...
ISSUED AT 850 PM MST WED FEB 19 2014
ADDING SNOW/BLOWING SNOW ADVISORY TO TELLER/NORTHERN EL PASO COUNTIES
FOR THE REST OF TONIGHT...BASED ON RADAR/SATELLITE TRENDS AND HI RES
MODEL FORECASTS FOR THE REMAINDER OF THE NIGHT. HRRR DEVELOPS GOOD
PERIOD OF SNOW/BLOWING SNOW ACROSS TELLER/MAINLY NORTHERN EL PASO
COUNTIES SHORTLY AND THEN CONTINUING FOR SEVERAL HOURS BEFORE
ENDING. ADVISORY AND UPDATED PRODUCTS WILL BE OUT SHORTLY. LW
UPDATE ISSUED AT 701 PM MST WED FEB 19 2014
LOADED LATEST OBSERVATIONS AND BLENDED INTO FORECAST. ADJUSTED
SKY COVER AND PRECIP GRIDS TO REFLECT LATEST RADAR AND SATELLITE
TRENDS...AS WELL AS SHORT TERM HI RES MODEL FORECASTS. LW
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 333 PM MST WED FEB 19 2014
STRONG UPPER TROUGH MOVING QUICKLY EASTWARD THROUGH THE GREAT BASIN
INTO WESTERN COLORADO THIS AFTERNOON...WITH SNOW DEVELOPING AND EVEN
A COUPLE LIGHTNING STRIKES WEST OF THE CONTINENTAL DIVIDE THIS
AFTERNOON. EXPECT SNOW TO BEGIN BY SUNSET OVER THE CENTRAL AND
SOUTHWEST MOUNTAINS...WITH A PERIOD OF HEAVY SNOW AND BLOWING SNOW
OVERNIGHT...ESPECIALLY FROM MONARCH PASS NORTHWARD. CURRENT SNOWFALL
FORECAST IN THE 5 TO 9 INCH RANGE LOOKS ON TRACK...HIGHEST AMOUNTS
LIKELY NORTH OF COTTONWOOD PASS. SURFACE COLD FRONT DROPPING
QUICKLY SOUTH THROUGH WYOMING AS OF 22Z...AND WILL MOVE RAPIDLY
SOUTH ACROSS EASTERN COLORADO THIS EVENING. NORTH WINDS FOLLOWING
THE FROPA WILL GUST IN THE 45-55 MPH RANGE...AS STRONG SURFACE
PRESSURE RISE CENTER DROPS INTO THE REGION 06-09Z. MAY BE A QUICK
BURST OF -SHRA/-SHSN BEHIND THE FRONT OVER THE EASTERN MOUNTAINS AND
PLAINS...WITH THE BEST CHANCE OF PRECIP NORTH OF THE ARKANSAS RIVER
AND EAST OF THE I-25 CORRIDOR. NOT LOOKING FOR MUCH IF ANY
ACCUMULATING SNOW...THOUGH VISIBILITY COULD FALL BELOW A MILE
FOR A BRIEF PERIOD UNDER THE HEAVIER SHOWERS. ANY PRECIP WILL
QUICKLY EXIT THE AREA THURSDAY MORNING...AND ONLY A FEW -SHSN WILL
BE FOUND LINGERING OVER THE CENTRAL MOUNTAINS BY AFTERNOON. STRONG
N-NW WINDS WILL CONTINUE MOST LOCATIONS THROUGH THE DAY...THOUGH
I-25 CORRIDOR WILL LIKELY SEE SOME DECREASE IN SPEEDS BY MID/LATE
AFTERNOON. MODEL RH FORECASTS KEEP ALL OF THE PLAINS ABOVE 15
PERCENT THRESHOLD FOR A FIRE WX HIGHLIGHT...BUT GIVEN ATROCIOUS
DEWPOINT FORECASTS OF LATE...EXPECT DRIEST AREAS ALONG THE NM BORDER
TO BECOME DRY ENOUGH TO WARRANT A RED FLAG WARNING...WHILE AREA
FARTHER NORTH LOOKS TOO COOL TO FORCE RH LOW ENOUGH. MAX TEMPS MOST
LOCATIONS SHOULD FALL 15-20F VERSUS WED MAXES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 333 PM MST WED FEB 19 2014
THURSDAY NIGHT AND FRIDAY...BRISK NW FLOW ALOFT WILL KEEP SCATTERED
OR EVEN LIKELY POPS FOR THE CENTRAL MTS IN PLACE THROUGH THU
NIGHT...THEN AS THE FLOW SHIFTS TO A MORE WESTERLY DIRECTION PCPN
CHANCES ARE EXPECTED TO DROP OFF THROUGH FRI. STRONG DOWNSLOPE FLOW
IS FORECAST TO BOOST MAX TEMPS FOR THE PLAINS INTO THE MID 50S TO
AROUND 60 F. GFS AND EC MODELS PAINT A COLD FRONT DROPPING DOWN THE
EASTERN HALF OF THE STATE LATE FRI EVE. THIS WILL SET UP THE REGION
FOR A COOLER SAT.
SATURDAY AND SUNDAY...A REINFORCING PUSH OF LLVL UPSLOPE FLOW WILL
KEEP COOLER AIR IN PLACE FOR THE PLAINS...AS WELL AS BRING ISOLATED
SNOW POPS TO THE PALMER DVD AND FAR EASTERN PLAINS BY SAT AFTN AND
EVE. MEANWHILE...ISOLATED TO SCATTERED POPS CONTINUE FOR THE CENTRAL
MTS. FOR SUN...THE COOL AIR REMAINS IN PLACE FOR MAC TEMPS IN THE
30S AND 40S FOR THE CWA...BUT IT LOOKS LIKE IT MIGHT REMAIN DRY FOR
ALL AREAS WITH WESTERLY FLOW ALOFT.
MONDAY THROUGH WEDNESDAY...NW FLOW ALOFT CONTINUES WITH A CONTINUED
ISOLATED THREAT OF SNOW FOR THE CENTRAL MTS. MODELS ARE INDICATING A
DRY COLD FRONT MONDAY EVE WHICH WOULD COOL MAX TEMPS FOR TUE.
OTHERWISE...ISOLATED SNOW FOR THE HIGHER ELEVATIONS OF LAKE AND
CHAFFEE COUNTIES...WHILE DRY AND WARMER FOR THE REMAINDER OF THE
FORECAST AREA. MOORE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 333 PM MST WED FEB 19 2014
KALS...VFR CONDITIONS TONIGHT AND THURSDAY. SHOWERS OVER THE
MOUNTAINS WILL SPREAD ACROSS THE VALLEY AFTER 00Z...AND HAVE A VCSH
MENTION 00Z-06Z. SHOWER ACTIVITY SHOULD DISSIPATE AFTER 06Z ALONG
WITH DECREASING WINDS. ON THU...GUSTY W-SW WINDS WILL AGAIN DEVELOP
AFTER 19Z.
KCOS...VFR CONDITIONS THROUGH THE NEXT 24 HOURS. A STRONG COLD FRONT
WILL DROP SOUTH ACROSS THE TERMINAL 03-05Z THIS EVENING. A FEW -SHSN
ARE POSSIBLE OVER THE HIGHER TERRAIN NORTH AND WEST OF THE
TERMINAL...BUT WON`T CARRY ANY PRECIP IN THE TAF AT THIS POINT.
NORTH WINDS BEHIND THE FRONT WILL LIKELY GUST TO NEAR 45 KTS
OVERNIGHT BEFORE GRADUALLY DECREASING DURING THE DAY THURSDAY.
KPUB...VFR CONDITIONS TONIGHT AND THURSDAY. A STRONG COLD FRONT WILL
MOVE SOUTH ACROSS THE TERMINAL 03-05Z THIS EVENING WITH NORTHERLY
WINDS BEHIND IT. GUSTS WILL APPROACH 40 KTS OVERNIGHT AND EARLY
THURSDAY MORNING.
OVER THE MOUNTAINS...CONTINENTAL DIVIDE WILL BE OBSCURED BY CLOUDS
AND SNOW OVERNIGHT AND THU MORNING...WITH GRADUALLY IMPROVING
CONDITIONS THU AFTERNOON...AFTER 20Z. REMAINDER OF THE MOUNTAINS
WILL SEE SCATTERED -SHSN AFTER 00Z...WITH AREAS OF MVFR/BRIEF IFR
CONDITIONS INTO THU MORNING.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM MST THURSDAY FOR COZ081-082-
084.
RED FLAG WARNING FROM 11 AM TO 6 PM MST THURSDAY FOR COZ229-230-
233-237.
WINTER WEATHER ADVISORY UNTIL 8 AM MST THURSDAY FOR COZ058-060.
&&
$$
UPDATE...LW
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
732 PM MST WED FEB 19 2014
.UPDATE...
&&
.SHORT TERM...COLD FRONT MOVING ACROSS THE CWA AS WINDS ON THE
PLAINS SHIFTING NORTH AND NORTHEAST AT 20-35KT. 88D SHOWING
REFLECTIVITY RAPIDLY DEVELOPING EARLY THIS EVENING PRETTY MUCH
LIKE THE RAP/HRRR HAVE BEEN SHOWING IN LATEST RUNS. JUST UPDATED
FORECASTS FOR LIKELY POPS FOR SNOW TONIGHT BUT OVERALL
ACCUMULATIONS STILL UNDER 2 INCHES. QG FIELDS HAVE BEEN SHOWING
STRONG UPWARD ASCENT AND GOOD INSTABILITY WITH THIS SYSTEM AND
APPEARS ABLE TO OVERCOME SOME OF THE DOWNSLOPE FLOW OFF THE FRONT
RANGE. GIVEN THE STRONG 3HR 5MB RISE INTO NEBRASKA PANHANDLE
EXPECT SOME NORTHEAST WINDS OVER SOUTHERN AND EASTERN PORTIONS OF
CWA. WILL MONITOR THIS EVENING IN CASE HIGHER SNOWFALL AMOUNTS ARE
NEEDED. THE RAP DID INDICATE HEAVIER AMOUNTS OVER THE PALMER
DIVIDE AND MAYBE NOT OUT OF THE QUESTION.
.AVIATION...STRONG NORTHERLY WINDS HAVE DEVELOPED AT KDEN AND WILL
MOVE INTO BJC/APA DURING THE NEXT HOUR. EXPECT CEILINGS TO LOWER
AND PRECIP TO DEVELOP BETWEEN 03-04Z. MAYBE A BRIEF SHOT OF
RAIN/SNOW BUT SHOULD TURN TO ALL SNOW RATHER QUICKLY. MOISTURE AND
UPSLOPE LOOK BETTER THIS EVENING AND WILL BE SHOWING LOWER
CIGS/VSBYS THAN CURRENT IN TAFS. SNOWFALL ACCUM STILL SHOULD BE
LESS THAN AN INCH AT BJC/DEN AND POSSIBLE UP TO 2 INCHES AT APA
WITH FAVORED NORTHERLY FLOW THERE. TAF UPDATES COMING.
&&
.PREV DISCUSSION... /ISSUED 219 PM MST WED FEB 19 2014/
SHORT TERM...UPPER TROUGH AXIS OVER NRN UT/WRN WY THIS AFTN
WILL CONTINUE IT TRACK ACROSS NORTHERN COLORADO LATE THIS
AFTERNOON AND TONIGHT. MDT TO STG MID AND UPPER LEVEL QG ASCENT
OVER NORTHERN COLORADO THROUGH THIS EVENING...WITH THE TROF AXIS
ALONG THE EASTERN CO BORDER BY 12Z THURSDAY. COLD FRONT ASSOCIATED
WITH THE SYSTEM MOVING INTO NWRN CO AT THIS TIME. SHOULD SEE SNOW
INCREASE IN COVERAGE NORTH OF INTERSTATE 70 THIS AFTERNOON...WITH
MODERATE TO HEAVY SNOWFALL OVERNIGHT. THE SYSTEM IS UNSTABLE AS
WELL SO COULD SEE A LIGHTNING STRIKE OR TWO AS THE SYSTEM PASSES
OVER THE STATE SO MAY ADD ISOLD THUNDER TO THE MOUNTAIN GRIDS AS
WELL. I WILL LIKELY EXTEND THE WINTER WEATHER ADVISORY INTO
THURSDAY MORNING. ACROSS THE NORTHEAST PLAINS...THE FRONT WILL
MOVE THROUGH THE AREA BY MID EVENING...WITH A STRONG NORTHERLY
PUSH FOLLOWING FROPA. WL KEEP CHC POPS ALONG THE URBAN CORRIDOR.
BEST CHC OF SNOW WILL OCCUR ON OR AFTER FROPA WITH GOOD INSTBY
OVERHEAD AND PRETTY GOOD QG ASCENT AS WELL. BEST CHC FOR
ACCUMULATING SNOWFALL WILL BE FURTHER EAST. SNOW MAY NOT STICK
INITIALLY...BUT COULD BECOME MORE OF AN ISSUE TOWARD MIDNIGHT. IT
IS A FAIRLY SHORT SNOW EVENT...2 TO 4 HOURS...SO WL KEEP EXPECTED
ACCUMULATIONS 2 INCHES OR LESS. STRONG WINDS FOLLOWING THE FRONT
MAY ALSO PRODUCE AREAS OF BLOWING SNOW SO HAVE ADDED THE GRIDS AS
WELL. ON THURSDAY...AMS WILL DRY OUT SIGNIFICANTLY AS STRONG
SUBSIDENCE DEVELOPS. GOOD OROGRAPHIC COMPONENT IN THE MORNING SO
WL GO WITH SOME LIGHT SNOW...PRIMARILY ALONG WEST FACING SLOPES.
WL EXTEND THE WINTER WEATHER ADVISORY UNTIL NOON. ACROSS THE
NORTHEAST PLAINS...STRONG NW WINDS WITH BORA TYPE SET UP. WL KEEP
THE STRONGER GUSTS UNDER HIGH WIND CRITERIA BUT KEEP GUSTS TO 50
MPH OVER THE ZONES ADJACENT TO NEBRASKA/KANSAS BORDERS.
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...A NORTHWEST FLOW
ALOFT WILL BE OVER THE CENTRAL ROCKIES THROUGH SUNDAY. WINDY
CONDITIONS ARE EXPECTED THURSDAY NIGHT IN AND NEAR FOOTHILLS AS
MODELS ARE HINTING AT A MOUNTAIN WAVE FORMING. SOME DIFFERENCE WITH
THE DETAILS IN THE MODELS...SO FOR NOW WILL GO WITH GUSTS OF 60 TO
70 MPH...JUST BELOW HIGH WIND CRITERIA.
SNOW WILL INCREASE IN THE MOUNTAINS AS MOISTURE INCREASES AND
DEEPENS. EXPECT MOUNTAIN SNOW FROM THURSDAY NIGHT THROUGH SATURDAY
NIGHT. BEST AND DEEPEST MOISTURE OCCURS THURSDAY NIGHT THEN AGAIN ON
FRIDAY NIGHT AND SATURDAY. THE OROGRAPHIC LIFT WILL BE THE PRIMARY
FORCING...SO EXPECT MOST OF THE SNOW OVER THE MOUNTAINS WITH JUST
LIGHT AMOUNTS IN THE VALLEYS. MAY BE ENOUGH FOR A WINTER WEATHER
ADVISORY. WILL LET TONIGHT`S SYSTEM PLAY OUT BEFORE ISSUING ANYTHING
FOR THE NEXT ROUND OF SNOW.
FOR NORTHEAST COLORADO...FRIDAY WILL BE WINDY WITH MILD TEMPERATURES
AHEAD OF AN APPROACHING COLD FRONT. THIS FRONT WILL MOVE THROUGH
LATE FRIDAY OR SATURDAY. THIS SCENARIO IS SIMILAR TO THIS PAST
SATURDAY WHERE MODELS DISAGREED ON HOW FAR SOUTH THE FRONT WOULD
GET. THE ECMWF IS AGAIN SHOWING THE COLDER AIR BEING DEEPER AND
ARRIVING SOONER. SINCE ECMWF WAS THE MOST ACCURATE WILL BASE THE
FORECAST ON THIS. WENT AHEAD AND LOWERED TEMPERATURES INTO THE 30S
FOR NORTHEAST COLORADO. BY SATURDAY EVENING...COULD SEE SOME SNOW
MOVE ONTO THE PLAINS AS A SHORT WAVE TROUGH MOVES OVER NORTHERN
COLORADO AND WYOMING.
FLOW ALOFT WILL WEAKEN EARLY NEXT WEEK AS AN UPPER LEVEL RIDGE
BUILDS OVER THE GREAT BASIN. THIS WILL REDUCE THE CHANCE FOR SNOW IN
THE MOUNTAINS. SHORT WAVE TROUGHS EMBEDDED IN THE NORTHWEST FLOW
ALOFT WILL PASS TO THE NORTHEAST OF COLORADO. THE TROUGH ON MONDAY
WILL PUSH A COLD FRONT THROUGH THE AREA DURING THE DAY
MONDAY...HELPING TO REINFORCE THE COOLER AIR. EXPECT TEMPERATURES TO
REMAIN AT OR BELOW NORMAL EARLY NEXT WEEK. CAN`T RULE OUT SOME
MOUNTAIN SNOW...BUT WITH THE MAIN FLOW ALOFT NORTH AND EAST OF THE
STATE...ANY SNOW WILL BE LIGHT.
AVIATION...VFR CIGS/VSBYS THROUGH 02Z. NW WINDS WILL PICK UP AS
SFC LOW SHIFTS MORE SOUTH AND EAST AND WE GET INTO MORE OF THE
PRESSURE GRADIENT. FROPA SHOULD OCCUR IN THE 05-06Z WITH A BRIEF
PERIOD OF NELY SFC WINDS...THEN IT WILL SWITCH BACK TO NNW. STRONG
DYNAMICS ALOFT AND GOOD INSTABILITY WITH THE FROPA...SO SNOW MAY
SWITCH OVER FAIRLY FAST. COULD ALSO SEE A BRIEF PERIOD OF
THUNDERSNOW WITH THE FROPA. NOT CONFIDENT ENUF TO PUT IT IN THE
TAFS AT THIS TIME. CIGS WILL DROP TO BLO 5K FT AFTER 02Z. IF SOME
THUNDER MIXES IN WITH THE SNOW...THEN IFR CIGS/VSBYS POSSIBLE FOR
A BRIEF PERIOD. WINDOW FOR SNOWFALL WILL BE IN THE 2-4 HOUR TIME
FRAME...04-08Z. IMPROVING CIGS AFTER 09Z...WITH NWLY WINDS
INCREASING AFTER 15Z THURSDAY.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON MST THURSDAY FOR COZ031-033-
034.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM....MEIER
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1046 AM MST TUE FEB 18 2014
.UPDATE...
&&
.SHORT TERM...WE GOT OUR LAST LITTLE SURGE OF WIND ALONG THE FRONT
RANGE RIGHT BEHIND THE TROUGH AXIS AS EXPECTED...BUT THE HIGH WIND
THREAT THERE IS NOW DIMINISHING. HOWEVER THE LOW LEVEL WINDS ON
THE PLAINS HAVE BEEN A LITTLE STRONGER. SURGE OF STRONGER
NORTHWEST WINDS HAVE PRODUCED GUSTS NEAR 50 KNOTS ACROSS THE
NORTHEAST CORNER...AND THE EDGE OF THE STRONGER WINDS IS JUST
ABOUT TO BACK INTO THE DENVER AREA. WITH A LITTLE INCREASE STILL
POSSIBLE OVER THE NEXT COUPLE HOURS...DECIDED TO GO AHEAD WITH A
HIGH WIND WARNING FOR THE NORTHEAST CORNER. WINDS CLOSER TO DENVER
MAY BE STRONGER THAN EXPECTED DURING THE MIDDAY PERIOD AS
WELL...BUT SHOULD STAY BELOW WARNING CRITERIA.
SOME DOUBT ABOUT THE TRANSITION TO AN ANTICYCLONIC CIRCULATION IN
THE LATE AFTERNOON OR EARLY EVENING...STILL THINK IT WILL HAPPEN
IN SOME FORM AS THE PLAINS WINDS START TO DECREASE...ESPECIALLY
WITH THE STABILITY CHANGE THAT SHOULD HAPPEN AROUND SUNSET.
NOT REALLY EXPECTING TOO MANY CHANGES TO THE GRIDS...BUT I WILL
NEED TO BOOST WINDS THROUGH THE EARLY AFTERNOON.
&&
.AVIATION...WINDS WILL BECOME A BIT MORE NORTHERLY AND WILL REMAIN
STRONG WITH GUSTS OF 30-40 KNOTS IN THE DENVER AREA THROUGH EARLY
AFTERNOON. SPEEDS MAY START TO DROP OFF AT KBJC. A SHIFT TO
EASTERLY WINDS IS EXPECTED BY LATE AFTERNOON...MAY BE A PERIOD OF
NE WINDS BUT THEN FAIRLY QUICKLY TURNING TO THE SOUTHEAST AT
LIGHTER SPEEDS. VFR CONDITIONS THROUGH TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 400 AM MST TUE FEB 18 2014/
SHORT TERM...MODEL DEPICTIONS SHOW THAT THE LEADING EDGE OF THE
PACIFIC JET STREAM IS JUST MOVING OVER NORTHERN COLORADO IN THE
PAST COUPLE HOURS. THE PLATTEVILLE PROFILER SHOWS WESTERLY WINDS
OF 55 KNOTS DOWN TO 650 MB...NEAR RIDGETOP LEVEL OVER THE
MOUNTAINS. FAVORABLE VERTICAL SHEAR PROFILES SHOULD REMAIN IN
PLACE FOR A FEW MORE HOURS...JUSTIFYING THE HIGH WIND WARNING OVER
THE MOUNTAINS AND FOOTHILLS. OVER THE PAST HOUR AND A HALF THE
DOPPLER RADAR HAS BEEN SHOWING THE MOUNTAIN WAVE SIGNATURE
DESCENDING OVER THE FRONT RANGE FOOTHILLS. MESONET OBSERVATIONS
FROM THE FOOTHILLS WEST OF BOULDER AND GOLDEN ARE SHOWING WIND
GUSTS TO 55-75 MPH WHILE 35-45 MPH GUSTS ARE BEING RECORDED FROM
EASTERN BOULDER EASTWARD TO ERIE. WINDY CONDITIONS SHOULD CONTINUE
THROUGH ABOUT MID-MORNING BEFORE TOO MUCH VERTICAL SHEAR DEVELOPS
AND THE MOUNTAIN WAVE BEGINS TO BREAK DOWN. THE RUC AND RAP MODELS
SHOW BREEZY CONDITIONS SPREADING ACROSS THE PLAINS THROUGH EARLY
AFTERNOON DUE TO STRONG VERTICAL MIXING OF WINDS ALOFT DOWN TO
THE SURFACE. SPEEDS ON THE PLAINS ARE NOT EXPECTED TO REACH HIGH
WIND CRITERIA...SO NO HIGHLIGHTS ARE ANTICIPATED OUT THERE.
THE WINDY CONDITIONS THIS MORNING HAVE KEPT TEMPERATURES MILD
ACROSS THE COUNTY WARNING AREA...AND SHOULD ALLOW TEMPERATURES TO
WARM TO THEIR MAX READINGS BY ABOUT THE NOON HOUR. OTHER THAN THE
WIND AND WARM TEMPERATURES...INCREASING HIGH CLOUDS BY AFTERNOON WILL
BE THE ONLY OTHER SENSIBLE WEATHER ELEMENT TO WORRY ABOUT. WINDS
WILL CONTINUE DECREASING TONIGHT AS PRESSURE GRADIENTS RELAX AND
THE UPPER JET MOVES NORTH OF THE STATE.
LONG TERM...AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE AREA WED AFTN
INTO WED NIGHT AND THEN BE EAST OF THE AREA BY THU MORNING.
MOISTURE WILL INCREASE IN THE MTNS AS THE SYSTEM APPROACHES WITH
THE FLOW SWITCHING FM SWLY TO NWLY BY EARLY WED EVENING AS THE
TROUGH MOVES ACROSS. WITH DECENT LAPSES RATE AND MDT QG ASCENT IN
THE MID LVLS THERE WILL LIKELY BE A PERIOD OF HEAVIER SNOW IN THE
00Z-06Z TIMEFRAME. AT THIS TIME IT LOOKS LIKE AN ADVISORY TYPE
EVENT IN MOST PLACES WITH GUSTY WINDS AS WELL. AT LOWER ELEVATIONS
SFC LOW PRES WILL INTENSIFY OVER ERN COLORADO DURING THE DAY AND
THEN MOVE EAST AS A CDFNT MOVES INTO NERN CO WED EVENING. AHEAD OF
THE FNT WILL SEE ANOTHER MILD DAY WITH READINGS IN THE 55 TO 60
DEGREE RANGE. AS THE CDFNT MOVES ACROSS WED EVENING WILL SEE A
BETTER CHC OF PCPN OVER NERN CO AS THE MAIN UPPER LEVEL TROUGH
MOVES ACROSS. SOUNDINGS SHOW RAIN WILL CHANGE TO SNOW AFTER 03Z SO
A FEW PLACES COULD PICK UP A QUICK INCH OR SO WITH PCPN DECREASING
AFTER 06Z.
ON THU DRIER AIR WILL SPREAD ACROSS THE AREA HOWEVER THERE WILL
STILL BE SOME LINGERING SHALLOW MOISTURE IN THE MTNS WHICH MAY LEAD
TO SOME OROGRAPHIC DRIVEN LIGHT SNOW. OVER NERN CO IT WILL BE DRY
HOWEVER IT WILL BE WINDY AS BNDRY LYR WINDS WILL BE IN THE 35-40 KT
RANGE. THUS AS MIXING OCCURS WILL PROBABLY SEE SOME GUSTS UP TO 50
MPH OVER THE PLAINS. AS FOR HIGHS WILL KEEP HIGHS MOSTLY IN THE
UPPER 30S TO LOWER 40S AS STG CAA WILL OCCUR.
FOR THU NIGHT THROUGH FRI NIGHT STG NWLY FLOW ALOFT WILL BE OVER THE
AREA AS A FEW DISTURBANCES MOVE ACROSS. MOISTURE WILL INCREASE IN
THE MTNS WITH FAVORABLE OROGRAPHICS AND DECENT LAPSE RATES BY FRI
ALONG WITH SOME QG ASCENT. THUS SHOULD SEE PERIODS OF SNOW IN THE
MTNS. AT LOWER ELEVATIONS THE THREAT FOR HIGH WINDS WILL INCREASE
IN AND NR THE FOOTHILLS THU NIGHT INTO FRI MORNING AS CROSS MTN FLOW
INCREASES TO 65-70 KT. OTHERWISE FOR FRI THE LOW LVL FLOW WILL BE
NWLY SO DO NOT EXPECT ANY PCPN OVER THE PLAINS. AS FOR HIGHS WILL
KEEP READINGS IN THE LOWER TO MID 40S OVER NERN CO.
BY THE WEEKEND THE FLOW ALOFT WILL REMAIN MAINLY NWLY. THE ECMWF
SHOWS MORE MOISTURE THAN THE GFS FOR SAT WHICH ALLOWS FOR A BETTER
CHC OF SNOW IN THE MTNS. FURTHERMORE THE ECWMF SHOWS A CDFNT MOVING
INTO NERN CO ON SAT WHILE THE GFS KEEPS IT FURTHER NORTH OVER SERN
WY AND THE NE PNHDL. AS A RESULT THE ECWMF SHOWS SOME UPSLOPE FLOW
DEVELOPING BY AFTN OVER NERN CO WITH A CHC OF PCPN ESPECIALLY SAT
NIGHT WHILE THE GFS SHOWS NO PCPN DUE TO HAVING THE FNT AND BETTER
MOISTURE FURTHER NORTH. FOR NOW WILL MENTION AT LEAST A SLIGHT CHC
OF PCPN OVER NERN CO FOR SAT NIGHT. FOR SUN BOTH THE ECMWF AND GFS
SHOW LIMITED MOISTURE IN THE MTNS AND OVER NERN CO THUS WILL ONLY
MENTION LOW POPS IN THE MTNS WITH DRY CONDITIONS OVER THE PLAINS.
LATEST 850-700 MB TEMPS WOULD KEEP READINGS MAINLY IN THE LOWER
TO MID 40S OVER NERN CO.
FOR EARLY NEXT WEEK THE ENDLESS PATTERN OF NWLY FLOW WILL CONTINUE.
THE ECMWF SHOWS ANOTHER CDFNT MOVING INTO NERN CO ON MON WHILE THE
GFS KEEPS IT FURTHER NORTH. FOR NOW WILL KEEP HIGHS OVER NERN CO IN
THE MID 30S TO LOWER 40S WITH THE COLDER READINGS ALONG THE WY-NE
BORDER. NEITHER MODEL SHOWS A LOT OF MOISTURE SO WILL JUST HAVE LOW
POPS IN THE MTNS AND ACROSS THE PLAINS.
AVIATION...WITH ALL OF THE WESTERLY FLOW COMING OVER THE
MOUNTAINS...ONE WOULD EXPECT WESTERLY WINDS AT THE AIRPORTS... AND
AT TIMES WE HAVE SEEN THAT. AT OTHER TIMES...SOUTHERLY DRAINAGE
WINDS HAVE DEVELOPED AT KDEN AND EVEN A BRIEF EASTERLY WIND HAS
OCCURRED AT KBJC. AFTER THE SUN COMES UP...WINDS SHOULD BECOME ALL
WEST AS DAYTIME HEATING MIXES LOW LEVEL WINDS DOWN TO THE SURFACE.
THE STRONGEST WINDS SHOULD BE OBSERVED THROUGH ABOUT 17Z WITH A
GRADUAL DECREASE THROUGH THE AFTERNOON. TYPICAL DRAINAGE WINDS ARE
EXPECTED TONIGHT. CEILINGS AND VISIBILITIES SHOULD BE UNLIMITED
ALL DAY.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ042-044-
048>051.
&&
$$
SHORT TERM...DANKERS
LONG TERM....RPK
AVIATION/UPDATE...GIMMESTAD
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
400 AM MST TUE FEB 18 2014
.SHORT TERM...MODEL DEPICTIONS SHOW THAT THE LEADING EDGE OF THE
PACIFIC JET STREAM IS JUST MOVING OVER NORTHERN COLORADO IN THE
PAST COUPLE HOURS. THE PLATTEVILLE PROFILER SHOWS WESTERLY WINDS
OF 55 KNOTS DOWN TO 650 MB...NEAR RIDGETOP LEVEL OVER THE
MOUNTAINS. FAVORABLE VERTICAL SHEAR PROFILES SHOULD REMAIN IN
PLACE FOR A FEW MORE HOURS...JUSTIFYING THE HIGH WIND WARNING OVER
THE MOUNTAINS AND FOOTHILLS. OVER THE PAST HOUR AND A HALF THE
DOPPLER RADAR HAS BEEN SHOWING THE MOUNTAIN WAVE SIGNATURE
DESCENDING OVER THE FRONT RANGE FOOTHILLS. MESONET OBSERVATIONS
FROM THE FOOTHILLS WEST OF BOULDER AND GOLDEN ARE SHOWING WIND
GUSTS TO 55-75 MPH WHILE 35-45 MPH GUSTS ARE BEING RECORDED FROM
EASTERN BOULDER EASTWARD TO ERIE. WINDY CONDITIONS SHOULD CONTINUE
THROUGH ABOUT MID-MORNING BEFORE TOO MUCH VERTICAL SHEAR DEVELOPS
AND THE MOUNTAIN WAVE BEGINS TO BREAK DOWN. THE RUC AND RAP MODELS
SHOWBREEZY CONDITIONS SPREADING ACROSS THE PLAINS THROUGH EARLY
AFTERNOON DUE TO STRONG VERICAL MIXING OF WINDS ALOFT DOWN TO THE
SURFACE. SPEEDS ON THE PLAINS ARE NOT EXPECTED TO REACH HIGH WIND
CRITERIA...SO NO HIGHLIGHTS ARE ANTICIPATED OUT THERE.
THE WINDY CONDITIONS THIS MORNING HAVE KEPT TEMPERATURES MILD
ACROSS THE COUNTY WARNING AREA...AND SHOULD ALLOW TEMPERATURES TO
WARM TO THEIR MAX READINGS BY ABOUT THE NOON HOUR. OTHER THAN THE
WIND AND WARM TEMPERATURES...INCREASING HIGH CLOUDS BY AFTERNOON WILL
BE THE ONLY OTHER SENSIBLE WEATHER ELEMENT TO WORRY ABOUT. WINDS
WILL CONTINUE DECREASING TONIGHT AS PRESSURE GRADIENTS RELAX AND
THE UPPER JET MOVES NORTH OF THE STATE.
.LONG TERM...AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE AREA WED AFTN
INTO WED NIGHT AND THEN BE EAST OF THE AREA BY THU MORNING.
MOISTURE WILL INCREASE IN THE MTNS AS THE SYSTEM APPROACHES WITH
THE FLOW SWITCHING FM SWLY TO NWLY BY EARLY WED EVENING AS THE
TROUGH MOVES ACROSS. WITH DECENT LAPSES RATE AND MDT QG ASCENT IN
THE MID LVLS THERE WILL LIKELY BE A PERIOD OF HEAVIER SNOW IN THE
00Z-06Z TIMEFRAME. AT THIS TIME IT LOOKS LIKE AN ADVISORY TYPE
EVENT IN MOST PLACES WITH GUSTY WINDS AS WELL. AT LOWER ELEVATIONS
SFC LOW PRES WILL INTENSIFY OVER ERN COLORADO DURING THE DAY AND
THEN MOVE EAST AS A CDFNT MOVES INTO NERN CO WED EVENING. AHEAD OF
THE FNT WILL SEE ANOTHER MILD DAY WITH READINGS IN THE 55 TO 60
DEGREE RANGE. AS THE CDFNT MOVES ACROSS WED EVENING WILL SEE A
BETTER CHC OF PCPN OVER NERN CO AS THE MAIN UPPER LEVEL TROUGH
MOVES ACROSS. SOUNDINGS SHOW RAIN WILL CHANGE TO SNOW AFTER 03Z SO
A FEW PLACES COULD PICK UP A QUICK INCH OR SO WITH PCPN DECREASING
AFTER 06Z.
ON THU DRIER AIR WILL SPREAD ACROSS THE AREA HOWEVER THERE WILL
STILL BE SOME LINGERING SHALLOW MOISTURE IN THE MTNS WHICH MAY LEAD
TO SOME OROGRAPHIC DRIVEN LIGHT SNOW. OVER NERN CO IT WILL BE DRY
HOWEVER IT WILL BE WINDY AS BNDRY LYR WINDS WILL BE IN THE 35-40 KT
RANGE. THUS AS MIXING OCCURS WILL PROBABLY SEE SOME GUSTS UP TO 50
MPH OVER THE PLAINS. AS FOR HIGHS WILL KEEP HIGHS MOSTLY IN THE
UPPER 30S TO LOWER 40S AS STG CAA WILL OCCUR.
FOR THU NIGHT THROUGH FRI NIGHT STG NWLY FLOW ALOFT WILL BE OVER THE
AREA AS A FEW DISTURBANCES MOVE ACROSS. MOISTURE WILL INCREASE IN
THE MTNS WITH FAVORABLE OROGRAPHICS AND DECENT LAPSE RATES BY FRI
ALONG WITH SOME QG ASCENT. THUS SHOULD SEE PERIODS OF SNOW IN THE
MTNS. AT LOWER ELEVATIONS THE THREAT FOR HIGH WINDS WILL INCREASE
IN AND NR THE FOOTHILLS THU NIGHT INTO FRI MORNING AS CROSS MTN FLOW
INCREASES TO 65-70 KT. OTHERWISE FOR FRI THE LOW LVL FLOW WILL BE
NWLY SO DO NOT EXPECT ANY PCPN OVER THE PLAINS. AS FOR HIGHS WILL
KEEP READINGS IN THE LOWER TO MID 40S OVER NERN CO.
BY THE WEEKEND THE FLOW ALOFT WILL REMAIN MAINLY NWLY. THE ECMWF
SHOWS MORE MOISTURE THAN THE GFS FOR SAT WHICH ALLOWS FOR A BETTER
CHC OF SNOW IN THE MTNS. FURTHERMORE THE ECWMF SHOWS A CDFNT MOVING
INTO NERN CO ON SAT WHILE THE GFS KEEPS IT FURTHER NORTH OVER SERN
WY AND THE NE PNHDL. AS A RESULT THE ECWMF SHOWS SOME UPSLOPE FLOW
DEVELOPING BY AFTN OVER NERN CO WITH A CHC OF PCPN ESPECIALLY SAT
NIGHT WHILE THE GFS SHOWS NO PCPN DUE TO HAVING THE FNT AND BETTER
MOISTURE FURTHER NORTH. FOR NOW WILL MENTION AT LEAST A SLIGHT CHC
OF PCPN OVER NERN CO FOR SAT NIGHT. FOR SUN BOTH THE ECMWF AND GFS
SHOW LIMITED MOISTURE IN THE MTNS AND OVER NERN CO THUS WILL ONLY
MENTION LOW POPS IN THE MTNS WITH DRY CONDITIONS OVER THE PLAINS.
LATEST 850-700 MB TEMPS WOULD KEEP READINGS MAINLY IN THE LOWER
TO MID 40S OVER NERN CO.
FOR EARLY NEXT WEEK THE ENDLESS PATTERN OF NWLY FLOW WILL CONTINUE.
THE ECMWF SHOWS ANOTHER CDFNT MOVING INTO NERN CO ON MON WHILE THE
GFS KEEPS IT FURTHER NORTH. FOR NOW WILL KEEP HIGHS OVER NERN CO IN
THE MID 30S TO LOWER 40S WITH THE COLDER READINGS ALONG THE WY-NE
BORDER. NEITHER MODEL SHOWS A LOT OF MOISTURE SO WILL JUST HAVE LOW
POPS IN THE MTNS AND ACROSS THE PLAINS.
&&
.AVIATION...WITH ALL OF THE WESTERLY FLOW COMING OVER THE
MOUNTAINS...ONE WOULD EXPECT WESTERLY WINDS AT THE AIRPORTS... AND
AT TIMES WE HAVE SEEN THAT. AT OTHER TIMES...SOUTHERLY DRAINAGE
WINDS HAVE DEVELOPED AT KDEN AND EVEN A BRIEF EASTERLY WIND HAS
OCCURRED AT KBJC. AFTER THE SUN COMES UP...WINDS SHOULD BECOME ALL
WEST AS DAYTIME HEATING MIXES LOW LEVEL WINDS DOWN TO THE SURFACE.
THE STRONGEST WINDS SHOULD BE OBSERVED THROUGH ABOUT 17Z WITH A
GRADUAL DECREASE THROUGH THE AFTERNOON. TYPICAL DRAINAGE WINDS ARE
EXPECTED TONIGHT. CEILINGS AND VISIBILITIES SHOULD BE UNLIMITED
ALL DAY.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 10 AM MST THIS MORNING FOR COZ033>036.
&&
$$
SHORT TERM...DANKERS
LONG TERM....RPK
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS ALBANY NY
1248 AM EST TUE FEB 18 2014
.SYNOPSIS...
HIGH PRESSURE WILL START TO MOVE OFF THE NEW ENGLAND
COAST TONIGHT. A FAST MOVING STORM SYSTEM WILL BRING IN LIGHT SNOW
ACROSS THE REGION ON TUESDAY. ANOTHER FAST MOVING SYSTEM WILL BRING IN
RAIN AND SNOW SHOWERS FOR WEDNESDAY. WARMER AIR WILL MOVE INTO THE
REGION BY THE LATTER PART OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1245 AM EST...AFTER A PERIOD OF MOSTLY CLEAR SKIES AND LIGHT
TO CALM WIND...TEMPS PLUMMETED ACROSS THE REGION...INTO THE SINGLE
DIGITS ABOVE AND BELOW ZERO. HOWEVER...CLOUDS ARE NOW
THICKENING...AND A LIGHT SOUTHEAST WIND WILL SOON ALSO DEVELOP.
THIS SHOULD ALLOW TEMPS TO RISE THE REMAINDER OF THE NIGHT...INTO
THE TEENS IN MOST AREAS BY DAYBREAK.
LOW PRESSURE IS CURRENTLY OVER SE LOWER MICHIGAN...WITH THE
GREATEST PRESSURE FALLS LOCATED ACROSS SOUTHERN ONTARIO AND FAR
WESTERN NYS. AS THIS LOW CONTINUES TO MOVE ENE...SOME LIGHT
SNOW WILL BE TOWARD DAYBREAK...AS IT SPREADS FROM SOUTHWEST TO
NORTHEAST ACROSS THE REGION. THE LATEST 3KM HRRR AND RAP13 SHOW
THE POTENTIAL FOR SNOW TO MOVE IN AFTER 09Z...ALTHOUGH THIS MAY BE
DELAYED SOMEWHAT AS A DEEP LAYER OF LOW/MID LEVEL DRY AIR IMPEDES
ITS INITIAL PROGRESS INTO THE REGION. WITH THE DRY AIRMASS IN
PLACE...IT MAY TAKE A LITTLE WHILE TO SATURATE THE COLUMN...SO
SOME OF THIS INITIAL PRECIP WILL BE LOST TO VIRGA. STILL...MANY
AREAS WILL BE STARTING TO SEE SOME SNOWFLAKES FALLING JUST BEFORE
SUNRISE IN OUR AREA...WITH A COATING POSSIBLE BY THE END OF THE
NIGHT ACROSS WESTERN AND SOUTHERN AREAS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/...
TUESDAY...THE AREA OF LOW PRESSURE WILL BE ACROSS THE EASTERN
GREAT LAKES BEFORE IT MAKES ITS TRANSITION TO THE COAST. SNOW WILL
CONTINUE TO OVERSPREAD THE ENTIRE AREA AND CONTINUE INTO THE EARLY
AFTERNOON HOURS. MOST AREAS WILL SEE 2-4 INCHES ACROSS THE CWA.
THE ONLY EXCEPTION WILL BE THE NEW ENGLAND COUNTIES WHERE A WINTER
WEATHER ADVISORY HAS BEEN HOISTED FOR 3-6 INCHES OF SNOW. THE
ADVISORY IS IN EFFECT FOR WINDHAM...BENNINGTON...BERKSHIRE AND
LITCHFIELD COUNTIES FROM 5 AM - 3 PM. MODEL GUIDANCE WAS IN FAIRLY
GOOD AGREEMENT FOR QPF. HAVE LEANED AGAINST THE NAM QPF AS IT WAS
A BIT ON THE HIGH SIDE AND FURTHER NORTH AND WEST WITH MAX QPF
VALUES. BEST FRONTOGENESIS/FORCING ON GUIDANCE IS BEST OVER THE
NEW ENGLAND AREA. THE LOW PRESSURE SYSTEM WILL MOVE OFF THE ME
COAST BY TUESDAY EVENING.
HIGH TEMPERATURES ON TUESDAY WILL START TO MODERATE WITH HIGHS IN
THE UPPER 20S TO LOWER 30S ACROSS THEN NORTHERN ZONES AND LOW TO
MID 3OS ACROSS THE SOUTHERN ZONES.
TUESDAY EVENING...WE WILL BE BETWEEN SYSTEMS AND HAVE A BRIEF
PERIOD OF CLEARING. LOW TEMPERATURES WILL BE IN THE TEENS TO
LOWER 20S.
WEDNESDAY - THURSDAY... ANOTHER SYSTEM WILL MOVE THROUGH THE
REGION BY WEDNESDAY AFTERNOON. THE PRECIPITATION ASSOCIATED WITH
WEDNESDAY SYSTEM WILL BE LIMITED AND OF THE SHOWERY TYPE.
TEMPERATURES WILL START TO BE ON THE INCREASE WITH HIGHS IN THE
UPPER 30S TO LOWER 40S. HIGH PRESSURE WILL BUILD ON THURSDAY AND
WE WILL SEE HIGH TEMPERATURES IN THE UPPER 30S ACROSS THE NORTH TO
LOW TO MID 40S ACROSS THE SOUTHERN TWO THIRDS OF THE REGION.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
A WARM FRONT WILL BE MOVING NORTHWARD ACROSS THE REGION DURING THE
THURSDAY NIGHT TIME PERIOD. 850 HPA TEMPS WILL RISE FROM NEAR 0 TO
+2 DEGREES C TO +7 TO +10 DEGREES C BY FRIDAY MORNING WITH THE
PASSAGE OF THE WARM FRONT. SOME LIGHT PRECIPITATION WILL FALL WITH
THE PASSAGE OF THE FRONTAL BOUNDARY...MAINLY IN THE FORM OF RAIN. IN
SOME SHELTERED MOUNTAIN VALLEYS OF THE ADIRONDACKS...SRN
GREENS...AND BERKSHIRES...TEMPERATURES MAY BE BELOW FREEZING FOR A
PERIOD...RESULTING IN SOME FREEZING RAIN. A LIGHT ACCRETION OF ICE
WILL BE POSSIBLE FOR THESE AREAS...AND WE WILL HIGHLIGHT THIS
POTENTIAL IN THE HWO STATEMENT. SFC TEMPS MAY FALL INITIALLY DURING
THE LATE EVENING HOURS...BUT SHOULD STEADILY RISE EVERYWHERE AFTER
MIDNIGHT. BY DAYBREAK FRIDAY...MOST AREAS SHOULD BE ABOVE
FREEZING...WITH TEMPS AS WARM AS THE LOW 40S IN THE CAPITAL
REGION/MID HUDSON VALLEY.
A STRONG COLD FRONT WILL PASS ACROSS THE REGION ON FRIDAY. THE
TIMING OF THE FRONT LOOKS TO BE SOMETIME BETWEEN THE LATE MORNING
AND MID AFTN HOURS. A LINE OF STEADY RAIN WILL ACCOMPANY THIS
BOUNDARY...ALONG WITH SOME GUSTY WINDS. TEMPS WILL REACH WELL INTO
THE 40S IN MOST AREAS AHEAD OF THIS FRONT...WITH FALLING TEMPS
BEHIND THE BOUNDARY.
HIGH PRESSURE WILL MOVE ACROSS THE REGION FOR FRIDAY NIGHT THROUGH
SATURDAY NIGHT. THIS SHOULD ALLOW FOR DRY WEATHER. TEMPS WILL STILL
BE A LITTLE ABOVE NORMAL...WITH UPPER 30S TO MID 40S FOR MAX TEMPS
ON SAT...AND MIN TEMPS ON BOTH FRI AND SAT NIGHT/S IN THE 20S.
A CLIPPER SYSTEM WILL MOVE ACROSS THE AREA FOR SUNDAY. ALTHOUGH
MOISTURE WILL BE QUITE LIMITED...THIS MAY ALLOW FOR SOME LIGHT SNOW
SHOWERS. HAVE GONE WITH SLIGHT CHC TO CHC POPS TO ACCOUNT FOR THIS
POSSIBILITY. TEMPS LOOK TO BE NEAR SEASONABLE WITH HIGHS IN THE
30S...AND LOWS IN THE TEENS/20S. HIGH PRESSURE LOOKS TO RETURN FOR
MONDAY WITH CONTINUED SEASONABLE TEMPERATURES.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
VFR CONDITIONS ARE EXPECTED THROUGH THE OVERNIGHT AS MID AND HIGH
LEVEL CLOUDS OVERSPREAD THE REGION. IT LOOKS TO BE DRY UNTIL ABOUT
13Z-14Z...WHEN LIGHT SNOW WILL SPREAD FROM SOUTHWEST TO NORTHEAST
ACROSS THE AREA AS AN AREA OF LOW PRESSURE APPROACHES FROM THE
GREAT LAKES REGION. SNOW WILL QUICKLY ALLOW FOR IFR CONDITIONS TO
DEVELOP...WHICH WILL CONTINUE THROUGH NEARLY THE ENTIRE DAY ON
TUESDAY. VSBY MAY FINALLY START TO IMPROVE BY EARLY TUESDAY
EVENING...ALTHOUGH CIGS WILL LIKELY STILL STAY MVFR DUE TO
LINGERING LOW LEVEL MOISTURE.
LIGHT/CALM WINDS TONIGHT WILL BECOME E-SE AT 5-10 KTS ON TUESDAY.
BY LATE IN THE DAY...THEY WILL SWITCH TO THE W-NW AT SIMILAR SPEEDS.
OUTLOOK...
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SN.
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN.
WEDNESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN.
THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. LIKELY RA.
FRIDAY: HIGH OPERATIONAL IMPACT. LIKELY RA.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
WITH A LIGHT SNOW EVENT IN STORE FOR TUESDAY...MORE SNOW/LIQUID WILL BE
ADDED TO OUR CURRENT PACK. SNOW DEPTHS ACROSS EAST CENTRAL NEW
YORK AND ADJACENT WESTERN NEW ENGLAND ARE GENERALLY FROM A FOOT TO
THREE FEET. ALTHOUGH WE HAVE WARMER TEMPERATURES IN THE FORECAST
FOR THE LATTER PART OF THE WEEK...OVERNIGHT LOWS WILL BE AROUND OR
SLIGHTLY BELOW FREEZING TO ALLOW A MELT FREEZE CYCLE TO TAKE
PLACE. THIS WILL HELP WITH A SLOW MELT AND HOPEFULLY ALLEVIATE ANY
FLOODING ISSUES.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
THE MONTHLY SNOWFALL TOTAL FOR FEBRUARY AT THE ALBANY INTERNATIONAL
AIRPORT IS AT 25.7 INCHES THROUGH THE 16TH. THIS AMOUNT IS ONLY 0.3 INCHES
FROM REACHING INTO THE TOP 10 FOR SNOWIEST FEBRUARYS SINCE 1885.
A LIGHT TO MODERATE SNOWFALL IS EXPECTED TUESDAY.
TOP 10 SNOWIEST FEBRUARYS ALBANY
1. 40.7 INCHES 1893
2. 34.5 INCHES 1962
3. 32.3 INCHES 1926
4. 31.7 INCHES 1950
5. 30.1 INCHES 2011
6. 28.6 INCHES 1993
7. 27.5 INCHES 1899
8. 26.1 INCHES 1914
9. 26.0 INCHES 1958
10. 26.0 INCHES 1988
LOOKING AT THE SEASONAL SNOWFALL IT STANDS AT 62.8 INCHES. NORMAL FOR
THE ENTIRE WINTER SEASON IS 59.1 INCHES.
SO HOW DOES THIS WINTER COMPARE TO RECENT WINTERS FOR ALBANY...
2012-13: 51.4 INCHES
2011-12: 23.3 INCHES
2010-11: 87.2 INCHES
2009-10: 45.4 INCHES
2008-09: 52.6 INCHES
2007-08: 61.1 INCHES
2006-07: 45.9 INCHES
2005-06: 30.2 INCHES
2004-05: 75.9 INCHES
2003-04: 65.1 INCHES
2002-03: 105.4 INCHES
2001-02: 47.4 INCHES
2000-01: 77.1 INCHES
ALBANY EXTREMES:
SNOWIEST 1970-71 WITH 112.5 INCHES
LEAST 1912-13 WITH ONLY 13.8 INCHES
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY FROM 5 AM EARLY THIS MORNING TO 3 PM
EST THIS AFTERNOON FOR CTZ001-013.
NY...NONE.
MA...WINTER WEATHER ADVISORY FROM 5 AM EARLY THIS MORNING TO 3 PM
EST THIS AFTERNOON FOR MAZ001-025.
VT...WINTER WEATHER ADVISORY FROM 5 AM EARLY THIS MORNING TO 3 PM
EST THIS AFTERNOON FOR VTZ013>015.
&&
$$
SYNOPSIS...VTK
NEAR TERM...FRUGIS/KL
SHORT TERM...VTK
LONG TERM...FRUGIS
AVIATION...FRUGIS/11
HYDROLOGY...VTK
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
649 AM EST TUE FEB 18 2014
.SYNOPSIS...
LOW PRESSURE NEAR THE GREAT LAKES WILL MOVE INTO EASTERN CANADA
TODAY. ANOTHER LOW PRESSURE SYSTEM WILL DEVELOP OFF THE NEW JERSEY
COAST THIS MORNING THEN MOVE TO THE CANADIAN MARITIMES BY TONIGHT.
THEN THE MAIN WEATHER STORY THE REST OF THIS WEEK WILL BE MILDER
WEATHER AND A SERIES OF FRONTS. A COLD FRONT WILL CROSS THE MID
ATLANTIC STATES MIDDAY WEDNESDAY. A WARM FRONT IS EXPECTED TO
ARRIVE THURSDAY NIGHT...AND BE IMMEDIATELY FOLLOWED BY A STRONG
COLD FRONT LATE FRIDAY. ANOTHER COLD FRONT MAY CROSS OUR AREA THIS
WEEKEND. TEMPERATURES SHOULD BE AT OR ABOVE NORMAL THROUGH AT
SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
630 UPDATE...THE PRECIPITATION CONTINUES TO END WEST TO EAST.
THUS...HAVE CANCELLED THE WINTER WEATHER ADVISORY ACROSS NE
MD...DE...EASTERN PA...AND FAR NW NJ. SOME BRIEF PERIOD OF
FREEZING RAIN REPORTED IN MILLVILLE...BUT THE SHOULD BE WARMING
ABOVE FREEZING SHORTLY...AND ALL OTHER REPORTS ARE OF SNOW OR
RAIN.
AT 3 AM...THE SNOW BAND CONTINUED TO TRANSLATE THROUGH THE REGION.
BASED ON UPSTREAM OBS...RADAR...AND SATELLITE TRENDS...EXPECT ONLY
VERY LIGHT SNOW LINGERING BEHIND THIS MAIN SNOW BAND. WV SATELLITE
IMAGERY SHOWING THE DRY SLOT LIFTING NORTH INTO THE REGION. AT THE
SAME TIME...THE UPPER LEVEL LOW IS BEGINNING TO OCCLUDE. A SECONDARY
SNOW BAND IS TRYING TO DEVELOP OVER CENTRAL PA...BUT THERE HAS BEEN
LITTLE EVIDENCE OF INCREASING ORGANIZATION IN THIS BAND...AND IR
SATELLITE IS SHOWING WARMING CLOUD TOPS. THIS IS IN LINE WITH THE
PATTERN THE 03Z HRRR WAS SHOWING WITH SNOW BANDS BECOMING LESS
ORGANIZED AS THEY APPROACH OUR REGION. THUS...EXPECT THE LOW TO
BEGIN TO FILL AND WEAKEN OVER THE NEXT FEW HOURS. HAVE TRENDED SNOW
TOTALS DOWN...BUT PLAN TO HOLD ON TO THE WINTER WEATHER ADVISORY FOR
AT LEAST A FEW MORE HOURS TO SEE WHAT KIND OF SNOW RATES THIS MAIN
BAND WILL PROVIDE AND IF THE SECONDARY BAND CAN GET ORGANIZED.
THERE IS ALSO A POSSIBILITY THAT PRECIPITATION COULD REDEVELOP NEAR
OR JUST OFF THE JERSEY SHORE AROUND 18Z AS THE UPPER LEVEL TROUGH
FINALLY LIFTS NE AWAY FROM THE REGION. HOWEVER...BY THIS
POINT...EXPECT TEMPERATURES HIGH ENOUGH TO SUPPORT RAIN NOT SNOW.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
BIGGEST CONCERN IN THE TONIGHT PERIOD IS THE POTENTIAL FOR FOG.
LATEST MODELS SHOW AFTER THE INITIAL MOISTENING IN THE LOW LEVELS
THIS MORNING BEHIND THE SNOW...DRIER AIR SHOULD BEGIN TO WORK INTO
THE REGION. AT THIS TIME...IT DOESN/T APPEAR THAT TEMPS WILL GET LOW
ENOUGH FOR SATURATED BOUNDARY LAYER CONDITIONS. THERE IS SOME CONCERN
HOWEVER...IF WINDS DROP OFF ENOUGH THAT PRIME RADIATIONAL COOLING
CONDITIONS WILL LEAD TO LOW TEMPS LOWER THAN WHAT IS CURRENTLY
FORECAST. IN ADDITION...IF THERE IS SIGNIFICANT SNOW PACK MELT TO
TODAY...THAT COULD ADD TO THE NEAR SURFACE MOISTURE. BUT FOR
NOW...TOO LOW OF A CHANCE TO MENTION IN THE FORECAST.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AT THE BEGINNING OF THE PD, A WK CDFNT WILL APPROACH THE REGION AD
CROSS THE AREA DURG THE FIRST HALF OF WED. THIS FRONT WILL BRING
MAINLY RAIN WITH IT, BUT IF THE PRECIP STARTS EARLY ENOUGH N AND W
THERE COULD BE SOME FREEZING RAIN N AND W OR SOME KIND OF WINTRY
MIX FOR A FEW HOURS. OVERALL QPF IS FAIRLY LIGHT.
BEHIND THIS FRONT, HIGH PRESSURE WILL BUILD IN FOR WED NIGHT INTO
THU, BRINGING DRY WX.
THEN, AS STRONG LOW PRES DEVELOPS OVER THE PLAINS AND MOVES EWD,
ITS ATTENDANT WMFNT WILL PUSH THRU THE REGION THU NIGHT. THE LOW
WILL ADVANCE NEWD INTO ERN CANADA AND ITS ASSOCD STRONG CDFNT WILL
CROSS THE REGION ON FRI. THIS FRONT WILL BRING SHOWERS, PSBLY SOME
THUNDER AND A DECENT SHOT OF RAIN...SOME OF IT COULD BE
HEAVY...FOR A TIME.
AFTER THIS FRONT PASSES, HIGH PRESSURE WILL BUILD BACK IN FOR
LATER FRI INTO AT LEAST SUN.
THEN, THE ECMWF TRIES TO DEVELOP ANOTHER WK LOW OVER THE OH VLY
AND PUSH IT EWD SUN NIGHT INTO MON WHILE THE ECMWF AND CMC ARE DRY
WITH A LARGE AREA OF HIGH PRESSURE BUILDING DOWN FROM CANADA OVER
THE CNTRL PORTION OF THE NATION AND SLOWLY MOVG EWD.
CONFIDENCE IS LOW ON WHICH MDL, IF ANY, WILL BE RIGHT AT THIS TIME
SCALE, SO WILL CONTINUE THE DRY FCST ATTM.
TEMPS WILL BE ON QUITE A ROLLER COASTER. WE WILL SEE ABOVE NRML
TEMPS FOR THE FIRST TIME IN QUITE SOME TIME. THIS WILL HELP MELT
SOME OF THE SNOW. UNFORTUNATELY IF IT DOES IT TO QUICKLY AND IF WE
GET DECENT RAIN ON FRI THERE COULD BE SOME FLOODING ISSUES.
TEMPS WILL BE AT OR ABOVE NRML FOR ABOUT FOR 6 DAYS BEFORE
RETURNING TO BELOW NRML VALUES BY THE END OF THE PD. ON WED HIGH
WILL MAINLY BE IN THE MID 40S THEY WILL RISE A FEW DEGREES ON THU
WITH MANY AREAS FROM THE I-95 CORRIDOR S AND E MAKING A RUN AT 50
DEGREES. FRI WILL BE THE WARMEST DAY AS WE WILL BE IN THE WARM
SECTOR WITH GOOD SWLY FLOW AHEAD OF THE CFP. DEPENDING ON THE
TIMING OF THE FRONT AND HOW MUCH SUN WE SEE, A 60 DEGREE READING
ON THE I-95 CORRIDOR IS NOT OUT OF THE QUESTION. TEMPS WILL BE A
BIT COOLER ON SAT BUT NOT UNBEARABLE AND WILL TREND MUCH COOLER BY
MONDAY.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
AS OF 08Z SNOW BAND IS MOVING THROUGH THE REGION. MINIMUM CONDITIONS
ARE AROUND 1/2SM SN OVC007 IN THE MIDDLE OF THE BAND. THE BAND
SHOULD BE EAST OF THE REGION NO LATER THAN 12Z. IN ITS WAKE...COULD
STILL SEE MVFR CEILINGS...AND ISOLATED CASES OF -SN REDUCING
VISIBILITY TO 3SM...BUT CONDITIONS SHOULD BE BETTER THAN WHAT WE ARE
SEEING NOW.
CONDITIONS SHOULD BE IMPROVING TO VFR BY 18Z FOR THE TERMINALS. ONCE
CONDITIONS IMPROVE...EXPECT VFR TO CONTINUE THROUGH THE TAF PERIOD.
HIGH RES MODELS SHOW SOME REDEVELOPMENT OF MOSTLY RAIN POSSIBLE
ALONG THE JERSEY SHORE AFTER 15Z...BUT AT THIS TIME IT LOOKS TO STAY
MOSTLY N OF KACY.
OUTLOOK...
WED...A SYS WILL MOVE THRU IN THE MRNG AND BRING MAINLY SHRA.
THERE CUD BE FZRA OR MIXED PRECIP OVER NRN AND WRN AREAS IF THE
PRECIP DEVELOPS EARLY ENOUGH WED AM. MVFR PSBL IFR IN THE MRNG
THEN IMPROVING TO VFR BY AFTN. SW WIND GUST 15-20 KT SHIFT NW
DURING THE AFTERNOON. MDT CONFIDENCE
WED NIGHT...GENLY VFR WITH PATCHY IFR FOG PSBL TOWARD SUNRISE IN
THE MORE RURAL AREAS. MDT CONFIDENCE
THU...VFR THROUGH THE DAY. CONDITIONS DETERIORATING TO IFR IN
ST/FOG/RAIN-DRIZZLE THURSDAY NIGHT. LLWS POSSIBLE BY DAYBREAK
FRIDAY. MDT CONFIDENCE
FRI...MVFR...AND POSSIBLY IFR IN ST/FOG/SHOWERS EXPECTED ACROSS
THE REGION IN THE MORNING. CFP FRI AFTN... BRINGING AN ABRUPT WIND
SHIFT...AND RETURN TO VFR. LLWS POTENTIAL DURING THE MORNING. SW
WIND GUSTS 20-30 KT THROUGH MIDDAY SHIFT NW AFTER THE CFP. MDT TO
HIGH CONFIDENCE.
SATURDAY...VFR. HIGH CONFIDENCE.
&&
.MARINE...
WINDS AND SEAS WILL CONTINUE TO INCREASE THROUGH AT LEAST MID DAY.
WIND DIRECTION WILL BE SHIFTING FROM SOUTHERLY TO WESTERLY THROUGH
THE DAY TODAY. WINDS SHOULD DECREASE BELOW SCA CONDITIONS BY EARLY
THIS EVENING AND STAY BELOW SCA CRITERIA THROUGH THE NIGHT.
OUTLOOK...
WED...SCA CONDS PSBL IN SW TO W FLOW.
THU...SUB-SCA CONDITIONS THROUGH THE DAY...BUT WIND AND SEAS
INCREASE THU NIGHT IN ADVANCE OF CDFNT.
FRI...SCA LIKELY. S WIND IN THE MRNG WILL SHIFT TO NW BEHIND CFP
IN THE AFTN.
SAT...SUB-SCA CONDS.
THE FIRST TWO WEEKS OF FEBRUARY THROUGH THE 16TH HAVE AVERAGED ABOUT
3 DEGREES (SOUTH) TO MORE THAN 6 DEGREES (NORTH)...ALL COLDER THAN
NORMAL!
SEASONAL SNOW TOTALS AND RANKING AS OF 7 AM TODAY-MONDAY FEBRUARY
17.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ009-010-012-013-015.
WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
NJZ020>022-027.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NJZ016>019.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
ANZ450>453.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430-
431-454-455.
&&
$$
SYNOPSIS...NIERENBERG
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...NIERENBERG
AVIATION...JOHNSON/NIERENBERG
MARINE...JOHNSON/NIERENBERG
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
345 AM EST TUE FEB 18 2014
.SYNOPSIS...
LOW PRESSURE NEAR THE GREAT LAKES WILL MOVE INTO EASTERN CANADA
TODAY. ANOTHER LOW PRESSURE SYSTEM WILL DEVELOP OFF THE NEW JERSEY
COAST THIS MORNING THEN MOVE TO THE CANADIAN MARITIMES BY TONIGHT.
THEN THE MAIN WEATHER STORY THE REST OF THIS WEEK WILL BE MILDER
WEATHER AND A SERIES OF FRONTS. A COLD FRONT WILL CROSS THE MID
ATLANTIC STATES MIDDAY WEDNESDAY. A WARM FRONT IS EXPECTED TO
ARRIVE THURSDAY NIGHT...AND BE IMMEDIATELY FOLLOWED BY A STRONG
COLD FRONT LATE FRIDAY. ANOTHER COLD FRONT MAY CROSS OUR AREA THIS
WEEKEND. TEMPERATURES SHOULD BE AT OR ABOVE NORMAL THROUGH AT
SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AT 3 AM...THE SNOW BAND CONTINUED TO TRANSLATE THROUGH THE REGION.
BASED ON UPSTREAM OBS...RADAR...AND SATELLITE TRENDS...EXPECT ONLY
VERY LIGHT SNOW LINGERING BEHIND THIS MAIN SNOW BAND. WV SATELLITE
IMAGERY SHOWING THE DRY SLOT LIFTING NORTH INTO THE REGION. AT THE
SAME TIME...THE UPPER LEVEL LOW IS BEGINNING TO OCCLUDE. A SECONDARY
SNOW BAND IS TRYING TO DEVELOP OVER CENTRAL PA...BUT THERE HAS BEEN
LITTLE EVIDENCE OF INCREASING ORGANIZATION IN THIS BAND...AND IR
SATELLITE IS SHOWING WARMING CLOUD TOPS. THIS IS IN LINE WITH THE
PATTERN THE 03Z HRRR WAS SHOWING WITH SNOW BANDS BECOMING LESS
ORGANIZED AS THEY APPROACH OUR REGION. THUS...EXPECT THE LOW TO
BEGIN TO FILL AND WEAKEN OVER THE NEXT FEW HOURS. HAVE TRENDED SNOW
TOTALS DOWN...BUT PLAN TO HOLD ON TO THE WINTER WEATHER ADVISORY FOR
AT LEAST A FEW MORE HOURS TO SEE WHAT KIND OF SNOW RATES THIS MAIN
BAND WILL PROVIDE AND IF THE SECONDARY BAND CAN GET ORGANIZED.
THERE IS ALSO A POSSIBILITY THAT PRECIPITATION COULD REDEVELOP NEAR
OR JUST OFF THE JERSEY SHORE AROUND 18Z AS THE UPPER LEVEL TROUGH
FINALLY LIFTS NE AWAY FROM THE REGION. HOWEVER...BY THIS
POINT...EXPECT TEMPERATURES HIGH ENOUGH TO SUPPORT RAIN NOT SNOW.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
BIGGEST CONCERN IN THE TONIGHT PERIOD IS THE POTENTIAL FOR FOG.
LATEST MODELS SHOW AFTER THE INITIAL MOISTENING IN THE LOW LEVELS
THIS MORNING BEHIND THE SNOW...DRIER AIR SHOULD BEGIN TO WORK INTO
THE REGION. AT THIS TIME...IT DOESN/T APPEAR THAT TEMPS WILL GET LOW
ENOUGH FOR SATURATED BOUNDARY LAYER CONDITIONS. THERE IS SOME CONCERN
HOWEVER...IF WINDS DROP OFF ENOUGH THAT PRIME RADIATIONAL COOLING
CONDITIONS WILL LEAD TO LOW TEMPS LOWER THAN WHAT IS CURRENTLY
FORECAST. IN ADDITION...IF THERE IS SIGNIFICANT SNOW PACK MELT TO
TODAY...THAT COULD ADD TO THE NEAR SURFACE MOISTURE. BUT FOR
NOW...TOO LOW OF A CHANCE TO MENTION IN THE FORECAST.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AT THE BEGINNING OF THE PD, A WK CDFNT WILL APPROACH THE REGION AD
CROSS THE AREA DURG THE FIRST HALF OF WED. THIS FRONT WILL BRING
MAINLY RAIN WITH IT, BUT IF THE PRECIP STARTS EARLY ENOUGH N AND W
THERE COULD BE SOME FREEZING RAIN N AND W OR SOME KIND OF WINTRY
MIX FOR A FEW HOURS. OVERALL QPF IS FAIRLY LIGHT.
BEHIND THIS FRONT, HIGH PRESSURE WILL BUILD IN FOR WED NIGHT INTO
THU, BRINGING DRY WX.
THEN, AS STRONG LOW PRES DEVELOPS OVER THE PLAINS AND MOVES EWD,
ITS ATTENDANT WMFNT WILL PUSH THRU THE REGION THU NIGHT. THE LOW
WILL ADVANCE NEWD INTO ERN CANADA AND ITS ASSOCD STRONG CDFNT WILL
CROSS THE REGION ON FRI. THIS FRONT WILL BRING SHOWERS, PSBLY SOME
THUNDER AND A DECENT SHOT OF RAIN...SOME OF IT COULD BE
HEAVY...FOR A TIME.
AFTER THIS FRONT PASSES, HIGH PRESSURE WILL BUILD BACK IN FOR
LATER FRI INTO AT LEAST SUN.
THEN, THE ECMWF TRIES TO DEVELOP ANOTHER WK LOW OVER THE OH VLY
AND PUSH IT EWD SUN NIGHT INTO MON WHILE THE ECMWF AND CMC ARE DRY
WITH A LARGE AREA OF HIGH PRESSURE BUILDING DOWN FROM CANADA OVER
THE CNTRL PORTION OF THE NATION AND SLOWLY MOVG EWD.
CONFIDENCE IS LOW ON WHICH MDL, IF ANY, WILL BE RIGHT AT THIS TIME
SCALE, SO WILL CONTINUE THE DRY FCST ATTM.
TEMPS WILL BE ON QUITE A ROLLER COASTER. WE WILL SEE ABOVE NRML
TEMPS FOR THE FIRST TIME IN QUITE SOME TIME. THIS WILL HELP MELT
SOME OF THE SNOW. UNFORTUNATELY IF IT DOES IT TO QUICKLY AND IF WE
GET DECENT RAIN ON FRI THERE COULD BE SOME FLOODING ISSUES.
TEMPS WILL BE AT OR ABOVE NRML FOR ABOUT FOR 6 DAYS BEFORE
RETURNING TO BELOW NRML VALUES BY THE END OF THE PD. ON WED HIGH
WILL MAINLY BE IN THE MID 40S THEY WILL RISE A FEW DEGREES ON THU
WITH MANY AREAS FROM THE I-95 CORRIDOR S AND E MAKING A RUN AT 50
DEGREES. FRI WILL BE THE WARMEST DAY AS WE WILL BE IN THE WARM
SECTOR WITH GOOD SWLY FLOW AHEAD OF THE CFP. DEPENDING ON THE
TIMING OF THE FRONT AND HOW MUCH SUN WE SEE, A 60 DEGREE READING
ON THE I-95 CORRIDOR IS NOT OUT OF THE QUESTION. TEMPS WILL BE A
BIT COOLER ON SAT BUT NOT UNBEARABLE AND WILL TREND MUCH COOLER BY
MONDAY.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
AS OF 08Z SNOW BAND IS MOVING THROUGH THE REGION. MINIMUM CONDITIONS
ARE AROUND 1/2SM SN OVC007 IN THE MIDDLE OF THE BAND. THE BAND
SHOULD BE EAST OF THE REGION NO LATER THAN 12Z. IN ITS WAKE...COULD
STILL SEE MVFR CEILINGS...AND ISOLATED CASES OF -SN REDUCING
VISIBILITY TO 3SM...BUT CONDITIONS SHOULD BE BETTER THAN WHAT WE ARE
SEEING NOW.
CONDITIONS SHOULD BE IMPROVING TO VFR BY 18Z FOR THE TERMINALS. ONCE
CONDITIONS IMPROVE...EXPECT VFR TO CONTINUE THROUGH THE TAF PERIOD.
HIGH RES MODELS SHOW SOME REDEVELOPMENT OF MOSTLY RAIN POSSIBLE
ALONG THE JERSEY SHORE AFTER 15Z...BUT AT THIS TIME IT LOOKS TO STAY
MOSTLY N OF KACY.
OUTLOOK...
WED...A SYS WILL MOVE THRU IN THE MRNG AND BRING MAINLY SHRA.
THERE CUD BE FZRA OR MIXED PRECIP OVER NRN AND WRN AREAS IF THE
PRECIP DEVELOPS EARLY ENOUGH WED AM. MVFR PSBL IFR IN THE MRNG
THEN IMPROVING TO VFR BY AFTN. SW WIND GUST 15-20 KT SHIFT NW
DURING THE AFTERNOON. MDT CONFIDENCE
WED NIGHT...GENLY VFR WITH PATCHY IFR FOG PSBL TOWARD SUNRISE IN
THE MORE RURAL AREAS. MDT CONFIDENCE
THU...VFR THROUGH THE DAY. CONDITIONS DETERIORATING TO IFR IN
ST/FOG/RAIN-DRIZZLE THURSDAY NIGHT. LLWS POSSIBLE BY DAYBREAK
FRIDAY. MDT CONFIDENCE
FRI...MVFR...AND POSSIBLY IFR IN ST/FOG/SHOWERS EXPECTED ACROSS
THE REGION IN THE MORNING. CFP FRI AFTN... BRINGING AN ABRUPT WIND
SHIFT...AND RETURN TO VFR. LLWS POTENTIAL DURING THE MORNING. SW
WIND GUSTS 20-30 KT THROUGH MIDDAY SHIFT NW AFTER THE CFP. MDT TO
HIGH CONFIDENCE.
SATURDAY...VFR. HIGH CONFIDENCE.
&&
.MARINE...
WINDS AND SEAS WILL CONTINUE TO INCREASE THROUGH AT LEAST MID DAY.
WIND DIRECTION WILL BE SHIFTING FROM SOUTHERLY TO WESTERLY THROUGH
THE DAY TODAY. WINDS SHOULD DECREASE BELOW SCA CONDITIONS BY EARLY
THIS EVENING AND STAY BELOW SCA CRITERIA THROUGH THE NIGHT.
OUTLOOK...
WED...SCA CONDS PSBL IN SW TO W FLOW.
THU...SUB-SCA CONDITIONS THROUGH THE DAY...BUT WIND AND SEAS
INCREASE THU NIGHT IN ADVANCE OF CDFNT.
FRI...SCA LIKELY. S WIND IN THE MRNG WILL SHIFT TO NW BEHIND CFP
IN THE AFTN.
SAT...SUB-SCA CONDS.
THE FIRST TWO WEEKS OF FEBRUARY THROUGH THE 16TH HAVE AVERAGED ABOUT
3 DEGREES (SOUTH) TO MORE THAN 6 DEGREES (NORTH)...ALL COLDER THAN
NORMAL!
SEASONAL SNOW TOTALS AND RANKING AS OF 7 AM TODAY-MONDAY FEBRUARY
17.
&&
.CLIMATE...
PHL 55.4 IS TIED FOR #3 OFFICIAL RECORDS BACK TO 1884
1. 78.7 2009-10
2. 65.5 1995-96
3. 55.4 2013-14
1898-99
5. 54.9 1977-78
ABE 65.4 IS #4 OFFICIAL RECORDS BACK TO 1922
1. 75.4 1993-94
2. 71.4 1995-96
3. 67.2 1966-67
4. 65.4 2013-14
5. 65.2 1960-61
ILG 45.9 IS #5 OFFICIAL RECORDS BACK TO 1894
1. 72.8 2009-10
2. 49.5 1957-58
3. 48.8 1906-07 (MISSING DAYS)
4. 46.1 2002-03
5. 45.9 2013-14
ACY 27.0 RANKED 18. OFFICIAL RECORDS BACK TO 1874.
FOR THE MONTH OF FEBRUARY THROUGH 7AM TODAY-MONDAY 2/17/14
PHL 18.3 RANKED 10TH AND MAY JUMP TO # 7 TUESDAY MORNING? HERE IS
THE PHILADELPHIA FEBRUARY SNOWFALL RANKING LISTING BELOW.
1. 51.5 2010
2. 31.5 1899
3. 29.6 2003
4. 27.6 1979
5. 26.1 1983
6. 24.1 1907
7. 19.0 1978
8/9 18.5 1967 AND 1934
10. 18.3 2014
ABE 35.2 RANKED #2 BEHIND THE 42.9 OF 2010.
ILG 16.5 RANKED #11 BEHIND THE 18.0 #10 OF 1899 AND THE #1 46.9 OF
2010.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
PAZ054-055-060>062-103>106.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
PAZ070-071-101-102.
NJ...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
NJZ001-007>010-012-013-015.
WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR
NJZ020>022-027.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NJZ016>019.
DE...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR DEZ002.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
DEZ001.
MD...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR MDZ015-
019-020.
WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
MDZ008-012.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
ANZ450>453.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ430-
431-454-455.
&&
$$
SYNOPSIS...NIERENBERG
NEAR TERM...JOHNSON
SHORT TERM...JOHNSON
LONG TERM...NIERENBERG
AVIATION...JOHNSON/NIERENBERG
MARINE...JOHNSON/NIERENBERG
CLIMATE...DRAG
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
429 AM EST TUE FEB 18 2014
.SYNOPSIS...
WEAK FRONT CROSSED THE AREA OVERNIGHT AND WILL STALL SOUTH OF THE
REGION TODAY AS HIGH PRESSURE BUILDS INTO THE AREA. THE FRONT WILL
MEANDER ACROSS THE REGION OVER THE NEXT COUPLE OF DAYS UNTIL A
STRONG COLD FRONT FINALLY EJECTS IT FROM THE REGION ON FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WEAK FRONTAL BOUNDARY CONTINUES TO CROSS THE AREA WITH ISOLATED
RAIN SHOWERS HAVING ENDED ACROSS THE FORECAST AREA. THE FRONT WILL
SLOWLY MOVE SOUTHWARD THROUGH THE DAY THEN RETURN NORTHWARD
TONIGHT AS A WARM FRONT. HAVE INCREASED POPS TONIGHT AS THE FRONT
MOVES THROUGH THE FORECAST AREA AND INCLUDED SLIGHT CHANCE OF
THUNDERSTORMS. POTENTIAL FOR THUNDERSTORMS IS LOW...HOWEVER THERE
IS ENOUGH INSTABILITY ALOFT TO INCLUDE A SLIGHT CHANCE.
TEMPERATURES THIS AFTERNOON WILL TOP OUT IN THE MID 60S TO AROUND
70 WITH OVERNIGHT LOWS TONIGHT IN THE UPPER 40S TO LOWER 50S.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
ENERGY WITH THE WARM FRONT WILL MOVE NORTHEAST OF THE REGION
AROUND DAYBREAK WITH HIGH PRESSURE BUILDING BACK INTO THE REGION.
THIS WILL AGAIN KEEP THE FRONTAL BOUNDARY OVER THE FORECAST AREA
WEDNESDAY WITH THE FRONT SLIDING SLIGHTLY NORTHWARD WEDNESDAY
NIGHT. LOW PRESSURE DEEPENING OVER THE CENTRAL MS VALLEY ON
THURSDAY WILL TRACK INTO THE CENTRAL GREAT LAKES THURSDAY NIGHT
AND PUSH A STRENGTHENING COLD FRONT TOWARD THE FORECAST AREA. WITH
THE FRONT ACROSS THE REGION THERE WILL BE A SLIGHT CHANCE OF
SHOWERS THROUGH THE SHORT TERM...MAINLY OVER THE NORTHERN
MIDLANDS...HOWEVER WITH LIMITED MOISTURE EXPECT ANY SHOWERS TO BE
LIGHT WITH A COUPLE HUNDREDTHS OF QPF AT MOST. TEMPERATURES WILL
CONTINUE TO WARM FOR THE WEDNESDAY AND THURSDAY WITH LOWER TO
MIDDLE 70S FOR AFTERNOON HIGHS AND OVERNIGHT LOWS IN THE UPPER 40S
TO LOWER 50S WEDNESDAY NIGHT AND MIDDLE TO UPPER 50S THURSDAY
NIGHT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH SATURDAY NIGHT WITH
DIFFERENCES FROM SUNDAY THROUGH MONDAY. COLD FRONT WILL CROSS THE
AREA ON FRIDAY WITH DRIER AIR QUICKLY BUILDING IN BEHIND THE
FRONT. HAVE INCLUDED THUNDERSTORMS TO THE FRIDAY FORECAST AS
INSTABILITY CONTINUES TO INCREASE AND THE DRY AIR MOVING IN BEHIND
THE FRONT IS ALSO A CONCERN. HIGH PRESSURE AND DRIER AIR WILL
REMAIN IN CONTROL OF THE REGION THROUGH SATURDAY NIGHT WITH MODEL
SOLUTIONS DIFFERING FOR SUNDAY AND MONDAY. GFS EJECTS THE HIGH
PRESSURE FASTER THEN THE ECMWF WITH BOTH MODELS RETURNING MOISTURE
TO THE REGION MONDAY AFTERNOON. WITH CONFIDENCE LOW FOR SUNDAY AND
MONDAY HAVE ONLY MADE MINOR ADJUSTMENTS TO THE FORECAST.
TEMPERATURES THROUGH THE LONG TERM WILL BE NEAR NORMAL TO SLIGHTLY
ABOVE NORMAL.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
A PERIOD OF MVFR IS POSSIBLE TOWARD DAYBREAK...OTHERWISE VFR
CONDITIONS EXPECTED.
STRATO-CUMULUS DECK WILL OVERSPREAD THE REGION OVERNIGHT AND
POSSIBLY LOWER TOWARD MORNING AS WEAK TROUGH MOVES THROUGH THE
REGION. CONFIDENCE HIGH THAT FOG WILL NOT DEVELOP GIVEN STRONG
BOUNDARY LAYER WINDS...BUT LOW CEILINGS MAY DEVELOP AS SUGGESTED
BY LAMP AND HRRR GUIDANCE. VAD WINDS FROM KCAE RADAR INDICATING
SOUTH TO SOUTHWEST WINDS AROUND 2000 FT 40 TO 50 KTS...SO WITH
WINDS LESS THAN 10 KTS AT THE SURFACE EXPECT A PERIOD OF NON-
CONVECTIVE WIND SHEAR...WEAKENING BY 12Z. CLEARING SKIES EXPECTED
BY MID MORNING AND SKY MAY GO CLEAR FOR MOST OF THE DAY. AFTER 00Z
EXPECT STRATO-CUMULUS CLOUDS TO SPREAD INTO THE REGION FROM
GEORGIA AHEAD OF APPROACHING WARM FRONT...BUT REMAIN VFR THROUGH
06Z WEDNESDAY.
EXTENDED AVIATION OUTLOOK...CEILING RESTRICTIONS POSSIBLE
WEDNESDAY MORNING AS WARM FRONT CROSSES THE REGION AND AGAIN ON
FRIDAY AS A STRONG COLD FRONT MOVES THROUGH.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1240 AM EST TUE FEB 18 2014
.SYNOPSIS...
A WEAK FRONT TO CROSS THE AREA OVERNIGHT. HIGH PRESSURE WILL
BRIEFLY TAKE HOLD TUESDAY. ANOTHER FRONT WILL AFFECT THE REGION
FRIDAY. A WARMING TREND IS STILL ON TAP FOR THIS WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
TONIGHT...A COLD FRONT WEILL CROSS THE AREA OVERNIGHT. AHEAD OF
THIS FRONT...SHOWERS CONTINUE TO BE SHOWN ON REGIONAL RADARS
MOVING THROUGH THE UPSTATE OF SC AND THROUGH NORTH-CENTRAL GA.
PRECIP IS FAST MOVING AND LIGHT TO MODERATE IN INTENSITY. MOISTURE
WITH THE FRONT WILL REMAIN LIMITED AND MOSTLY CONFINED TO THE LOW
LEVELS. SHOWERS SHOULD WEAKEN SLIGHTLY AS THEY APPROACH THE CWA
LATE TONIGHT. AS SUCH HAVE REMAINED WITH SLIGHT CHANCE POPS
ACROSS THE NORTHERN AND WESTERN MIDLANDS WITH GENERALLY NO POPS
ELSEWHERE AS DOWNSLOPING FURTHER DIMINISHES REMAINING MOISTURE.
INCREASING CLOUDS SHOULD KEEP OVERNIGHT LOWS IN THE LOW TO MID
40S.
TUESDAY...THE FRONT WILL MOVE EAST OF THE MIDLANDS AND CSRA
AROUND SUNRISE. HIGH PRESSURE WILL QUICKLY CROSS THE AREA AS THE
FRONT BECOMES STATIONARY ALONG THE GULF COAST. WENT WITH MOS
CONSENSUS FOR HIGHS TUESDAY IN THE MID 60S TO LOWER 70S.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT...UPPER AND SURFACE LOW
PRESSURE WILL BE OFF THE NEW ENGLAND COAST BY TUESDAY NIGHT WITH
THE ASSOCIATED FRONT ALSO OFFSHORE. ANOTHER AREA OF SURFACE LOW
PRESSURE WILL BE CENTERED OVER SOUTH CENTRAL CANADA WITH A COLD
FRONT DRAPED ACROSS THE OHIO AND TENNESSEE VALLEYS. MOISTURE AND
CLOUDINESS WILL INCREASE ACROSS THE FORECAST AREA AHEAD OF THE
FRONT LATE TUESDAY INTO WEDNESDAY. GFS PRECIPITABLE WATER VALUES
ARE AROUND 1 INCH WEDNESDAY MORNING. THE FRONT WILL CROSS THE
FORECAST AREA WEDNESDAY MORNING BRINGING ONLY A SLIGHT CHANCE OF
RAIN. SURFACE HIGH PRESSURE WILL RETURN BY WEDNESDAY AFTERNOON.
ABOVE NORMAL TEMPERATURES ON WEDNESDAY IN THE LOWER TO MIDDLE 70S.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...MODELS ARE IN GOOD
AGREEMENT SHOWING A LARGE TROUGH DEVELOPING OVER THE ROCKIES
REGION BY EARLY THURSDAY. THE UPPER TROUGH WILL DIG TOWARD THE
CENTRAL PLAINS WITH A DOWNSTREAM RIDGE OVER THE EASTERN CONUS. AT
THE SURFACE...AN AREA OF LOW PRESSURE CENTERED OVER THE CENTRAL
PLAINS EARLY THURSDAY WILL SHIFT NORTHEASTWARD TOWARD THE GREAT
LAKES AND DEEPEN WITH A WARM FRONT EXTENDING INTO THE FORECAST
AREA. CONTINUED TO INDICATE A SLIGHT CHANCE OF RAIN ALONG THE WARM
FRONT ON THURSDAY. TEMPERATURES ON THURSDAY WILL BE ABOVE NORMAL
WITH UPPER RIDGING AND SOUTHERLY FLOW INTO THE AREA. EXPECT HIGHS
IN THE LOW TO MID 70S.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
FRIDAY THROUGH FRIDAY NIGHT...SURFACE LOW PRESSURE WILL CONTINUE
TO DEEPEN AS IT SHIFTS NORTHEASTWARD INTO CANADA EARLY FRIDAY WITH
A COLD FRONT DRAPED ACROSS THE APPALACHIANS. MODELS SHOW AMPLE
MOISTURE ACROSS THE AREA FRIDAY MORNING WITH GFS PRECIPITABLE
WATER VALUES AROUND 1.4 INCHES AT 12Z. THE COLD FRONT WILL CROSS
THE FORECAST AREA DURING THE FRIDAY MORNING/EARLY AFTERNOON TIME
FRAME WITH RAIN LIKELY. THE SPC HAS NORTHERN AND CENTRAL GEORGIA
AND THE CAROLINAS IN ITS DAY 5 CONVECTIVE OUTLOOK. STRONG FLOW
ALOFT MAY RESULT IN A DAMAGING WIND THREAT. THE COLD FRONT SHOULD
BE EAST OF THE FORECAST AREA BY FRIDAY EVENING AS THE UPPER TROUGH
SHIFTS EASTWARD AND EXPANDS ACROSS THE EASTERN CONUS.
SATURDAY THROUGH MONDAY...THE FRONTAL BOUNDARY MAY STALL ALONG
THE COAST ON SATURDAY WITH SURFACE HIGH PRESSURE RIDGING INTO THE
FORECAST AREA BEHIND IT. MOISTURE WILL INCREASE AGAIN ON SUNDAY
WITH MODEL PRECIPITABLE WATER VALUES RETURNING TO OVER AN INCH.
THE NEXT COLD FRONT WILL APPROACH FROM THE WEST MONDAY WITH HIGH
PRESSURE AND DRY AIR RETURNING TUESDAY.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
A PERIOD OF MVFR IS POSSIBLE TOWARD DAYBREAK...OTHERWISE VFR
CONDITIONS EXPECTED.
STRATO-CUMULUS DECK WILL OVERSPREAD THE REGION OVERNIGHT AND
POSSIBLY LOWER TOWARD MORNING AS WEAK TROUGH MOVES THROUGH THE
REGION. CONFIDENCE HIGH THAT FOG WILL NOT DEVELOP GIVEN STRONG
BOUNDARY LAYER WINDS...BUT LOW CEILINGS MAY DEVELOP AS SUGGESTED
BY LAMP AND HRRR GUIDANCE. VAD WINDS FROM KCAE RADAR INDICATING
SOUTH TO SOUTHWEST WINDS AROUND 2000 FT 40 TO 50 KTS...SO WITH
WINDS LESS THAN 10 KTS AT THE SURFACE EXPECT A PERIOD OF NON-
CONVECTIVE WIND SHEAR...WEAKENING BY 12Z. CLEARING SKIES EXPECTED
BY MID MORNING AND SKY MAY GO CLEAR FOR MOST OF THE DAY. AFTER 00Z
EXPECT STRATO-CUMULUS CLOUDS TO SPREAD INTO THE REGION FROM
GEORGIA AHEAD OF APPROACHING WARM FRONT...BUT REMAIN VFR THROUGH
06Z WEDNESDAY.
EXTENDED AVIATION OUTLOOK...CEILING RESTRICTIONS POSSIBLE
WEDNESDAY MORNING AS WARM FRONT CROSSES THE REGION AND AGAIN ON
FRIDAY AS A STRONG COLD FRONT MOVES THROUGH.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
918 PM CST WED FEB 19 2014
.DISCUSSION...
918 PM CST
EVENING UPDATE...
KEY UPDATE THIS EVENING IS THAT WE WILL BE HOISTING A HIGH WIND
WATCH FOR THE ENTIRE AREA STARTING AT 00Z TOMORROW EVENING.
INTENSE WARM ADVECTION DRIVEN PRECIP CURRENTLY ACROSS SOUTHERN IA
AND NORTHERN MO AHEAD OF DEVELOPING SURFACE LOW OVER CENTRAL
PLAINS WILL OVERSPREAD AREA LATE TONIGHT. BIGGEST CONCERN IS WITH
SURFACE TEMPERATURES ESPECIALLY NORTH OF INTERSTATE 80 AND ALSO
TEMPERATURES ALOFT DUE TO EVAPORATIONAL/DYNAMIC COOLING MAINLY
ALONG/NORTH OF I-88 AS PRECIP BEGINS. SURFACE WET BULB 0 VALUES
WITH DEWPOINTS CURRENTLY IN THE 20S NORTH OF I-80 WILL BE AT OR
BELOW FREEZING UNTIL 12Z OR SO WE ADDED IN FREEZING MENTION ALONG
I-80 CORRIDOR. STRONG WARM SURGE WITH H8 TEMPS WARMING TO +6 OR
+7C FROM SOUTH SHOULD AID IN WARMING ENTIRE COLUMN ABOVE FREEZING
BY DAYBREAK. FARTHER NORTH/ALONG NORTH OF I-88...DRY EAST FLOW
ALOFT WILL CAUSE COLUMN TO COOL TO OR BELOW FREEZING AS IT TRIES
TO SATURATE. THUS THERE COULD BE A BURST OF ACCUMULATING
SNOW/SLEET...FOLLOWED BY TRANSITION TO ZR AND THEN PLAIN RAIN BY
14 TO 15Z TOMORROW. WOULD EXPECT IMMEDIATE DOWNTOWN CHICAGO TO BE
AT LESS OF A THREAT OF SNOW AND BRIEF ICE ACCUMS DUE TO VERY MILD
TEMPS THE PAST FEW DAYS. SURFACE TEMPS WILL NEED TO BE MONITORED
CLOSELY REGARDING POTENTIAL FOR ZR TO HOLD ON A BIT LONGER IN
PARTS OF FAR NORTHERN IL TOMORROW AM. WILL CONTINUE WITH SPS FOR
SNOW/ICE THREAT.
STILL ON TRACK FOR RAPID WARM UP TOMORROW AFTERNOON...WHICH COULD
RESULT IN AREAS OF DENSE FOG BUT MORE IMPORTANTLY ACCELERATE
SNOWMELT ON TOP OF WHAT OCCURRED WITH THE HEAVY RAIN IN THE AM.
THUS HAVE MADE NO CHANGES TO FLOOD WATCH. ISOLATED TSRA ARE
POSSIBLE IN STEEP MIDLEVEL LAPSE RATES UNDER DRY SLOT OF
INTENSIFYING CYCLONE.
FINALLY...REGARDING WINDS...VERY IMPRESSIVE SET-UP AS LOW LIFTS TO
SOUTHERN WI TOMORROW EVENING SWINGING POWERFUL COLD FRONT THROUGH
AREA. VERY SHARP CAA AND STRONG ISALLOBARIC PRESSURE RISES WILL
MAKE IT MUCH EASIER TO TAP INTO 50+ KT WINDS AT TOP OF THE
CHANNEL. SUSTAINED WESTERLY WIND SPEEDS COULD ALSO BE UP TO 30 KT.
THUS WITH POTENTIAL FOR 50+ KT GUSTS AND 30+ KT SUSTAINED
SPEEDS...WILL HOIST HIGH WIND WATCH FOR ENTIRE CWA STARTING 00Z
THURSDAY EVENING. WATCH ENDS A BIT EARLIER IN THE FAR SOUTH WHERE
WINDS MAY DIMINISH SLIGHTLY SOONER...BUT GOES TO 12Z FRIDAY FOR
MOST OF THE AREA.
RC
&&
.PREV DISCUSSION...
303 PM CST
SHORT TERM...TONIGHT THROUGH THURSDAY PM...
A VERY DYNAMIC AND COMPLEX STORM SYSTEM WILL IMPACT THE AREA LATE
TONIGHT THROUGH THURSDAY EVENING. THIS WILL PRESENT A PLETHORA OF
FORECAST CONCERNS OVER THE NEXT 24 TO 36 HOURS. THESE INCLUDE:
1.) THE THREAT FOR ACCUMULATING SNOW AND ICE AT THE ONSET OVERNIGHT
TONIGHT...PARTICULARLY ACROSS FAR NORTHERN ILLINOIS ALONG AND NORTH
OF INTERSTATE 88.
2.)RAINFALL AMOUNTS AND HYDRO ISSUES ON THURSDAY.
3.)POTENTIAL FOR SOME STRONG THUNDERSTORMS THURSDAY AFTERNOON.
4.)POTENTIAL FOR AREAS OF FOG ON THURSDAY.
5.)THE SYNOPTIC WINDS ON THE BACK SIDE OF THE SYSTEM LATE THURSDAY
AFTERNOON AND INTO THURSDAY NIGHT.
THE 12 UTC GLOBAL MODELS HAVE THE BEST HANDLE ON THE EVOLUTION AND
TRACK OF THIS STORM SYSTEM OVER THE NEXT 36 HOURS. AS SUCH...THE 12
UTC NAM WAS A FAR EAST OUTLIER ON THE SURFACE LOW TRACK. IN MOST
CASES...THE 12 UTC NAM WAS A GOOD 100 TO 150 MILES EAST OF THE
GLOBAL MODELS AND ENSEMBLE SOLUTIONS...SO THE 12 UTC NAM WAS NOT
FOLLOWED.
OVERALL...CYCLOGENESIS WILL SET UP ACROSS THE FRONT RANGE OF THE
COLORADO ROCKIES THIS EVENING IN ASSOCIATION WITH A STOUT SHORT WAVE
DISTURBANCE...NOW PUSHING ACROSS THE INTER-MOUNTAIN WEST. THIS WILL
RESULT IN A SURFACE LOW AROUND 992 MB...WHICH SHOULD PUSH EASTWARD
ACROSS THE KANSAS OKLAHOMA STATE LINE OVERNIGHT. THE MID LEVEL
SYSTEM WILL BE FORCED TO BECOME NEGATIVELY TILTED AS IT ENCOUNTERS
RAPIDLY BUILDING HIGHS ACROSS THE GREAT LAKES REGION EARLY THURSDAY.
AS A RESULT...THE SURFACE LOW WILL DEVELOP EXPLOSIVELY...WITH THE
CENTRAL PRESSURE EXPECTED TO DROP NEARLY 12 MB IN 12 HOURS AS THE
LOW LIFTS NORTHEASTWARD TO SOUTHEASTERN WISCONSIN BY EARLY THURSDAY
EVENING. THE LOW WILL LIKELY CONTINUE DEEPENING TO AROUND 970 MB BY
FRIDAY MORNING AS IT MOVES ACROSS THE UPPER GREAT LAKES REGION.
THE RAPID DEEPENING OF THE CENTRAL PRESSURE OF THIS LOW ALONE SAYS
THAT THIS WILL BE A NOTABLE WEATHER MAKER FOR MUCH OF THE CENTRAL
CONUS. PRECIPITATION WILL LIKELY ONSET QUICKLY ACROSS MOST OF
ILLINOIS AND INTO INDIANA TONIGHT AFTER 1 OR 2 IN THE MORNING AS 45
TO 50 KT LOW LEVEL JET DEVELOPS AND NOSES INTO THE REGION. THIS WILL
SET UP A VERY IMPRESSIVE SURGE OF GULF MOISTURE...WITH PWATS QUICKLY
INCREASING FROM ONLY A TENTH OR TWO OF AN INCH...TWO AROUND 1 INCH
BY DAYBREAK THURSDAY. CLIMATOLOGICALLY SPEAKING...1 INCH PWATS THIS
TIME OF YEAR RANK IN THE 99 TH PERCENTILE...SO HEAVY RAINFALL WILL
DEFINITELY BE A CONCERN. FOR MORE INFO ON THE HYDRO...SEE THE HYDRO
DISCUSSION BELOW.
THERE CONTINUES TO BE CONCERNS OF A WINTER MIX OF SNOW...FREEZING
RAIN AND SLEET AT THE ONSET OF THE PRECIPITATION
OVERNIGHT...PARTICULARLY AREAS ALONG AND NORTH OF INTERSTATE 88. IT
APPEARS THAT STRONG DYNAMIC FORCING WILL SET UP ALONG THE NOSE OF
THE LOW LEVEL JET...AND THIS STRONG FORCING COMBINED WITH
EVAPORATION COOLING COULD RESULT IN A COLUMN COLD ENOUGH FOR ALL
SNOW...ESPECIALLY CLOSER TO THE WISCONSIN BOARDER. THIS COULD RESULT
IN A PERIOD OF MODERATE TO HEAVY SNOW AND SLEET ACROSS FAR NORTHERN
ILLINOIS TONIGHT INTO VERY EARLY THURSDAY MORNING BEFORE THE WARM
SURGE KICKS NORTHWARD...CHANGING EVERYTHING OVER TO LIQUID. MODEL
BUFFER SOUNDINGS ACROSS THIS REGION ARE VERY CONCERNING...WITH THE
PROFILES INDICATING A NEARLY ISOTHERMAL LAYER FROM THE SURFACE UP TO
AROUND 700 MB HUGGING THE FREEZING POINT...AND VERY STEEP MID LEVEL
LAPSE RATES ABOVE THIS ISOTHERMAL LAYER. SO ALTHOUGH THERE MAY ONLY
BE A COUPLE HOUR PERIOD SUPPORTIVE OF SNOW...SLEET AND FREEZING
RAIN...THERE COULD BE A FEW INCHES OF SNOW ACCUMULATION AND A FEW
HUNDREDTHS OF AN INCH OF ICE ACCUMULATION FAR NORTH PRIOR TO THE
CHANGE OVER TO RAIN...ESPECIALLY WITH ANY CONVECTIVE ELEMENTS.
CONFIDENCE REMAINS LOW...BUT I HAVE ADDED SOME SNOW AND ICE
ACCUMULATIONS INTO THE FORECAST...WITH THE POTENTIAL OF SOME RAPID
SNOW ACCUMULATIONS. I WILL HIGHLIGHT THIS THREAT IN AN SPS...AND
PASS ALONG THE CONCERNS TO THE EVENING SHIFT TO SEE IF ANY WINTER WX
HEADLINE WILL BE NEEDED.
ANY WINTER PRECIP WILL QUICKLY COME TO AN END EARLY THURSDAY
MORNING...WITH PERIODS OF RAIN AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING AS THE WARM FRONT SHIFTS ACROSS NORTHERN
ILLINOIS. IN ADDITION TO THE THUNDERSTORMS AND HEAVY RAIN
POTENTIAL...THERE IS A THREAT OF FOG...ESPECIALLY IN THE VICINITY
OF THE WARM FRONT AND SURFACE LOW. A STRONG COLD FRONT WILL BEGIN TO
PUSH ACROSS THE AREA DURING THE AFTERNOON...AND THIS LOOKS TO BE THE
FOCUS FOR A LINE OF STORMS. IT CURRENTLY APPEARS THE BETTER THREAT
FOR MORE WIDESPREAD SEVERE STORMS WILL BE SOUTH OF THE AREA. THE
EXTENSIVE SNOW PACK ACROSS THE AREA MAY RESULT IN A NEAR SURFACE
INVERSION THAT MAY KEEP THE STORMS FROM ROOTING THEMSELVES IN THE
BOUNDARY LAYER. BECAUSE OF THIS...ALTHOUGH THE WINDS WILL BE
SCREAMING UP OVER 50 KT OFF THE SURFACE...THEY MAY HAVE A HARD TIME
BEING FORCED TO THE GROUND WITH THE STORMS. THEREFORE...ALTHOUGH
SOME ISOLATED SEVERE WIND GUSTS ARE POSSIBLE WITH THESE AFTERNOON
SHOWERS/STORMS...IT APPEARS THE MORE WIDESPREAD ACTIVITY WILL REMAIN
SOUTH OF MUCH OF THE AREA.
A DRY MID LEVEL DRY SLOT WILL PUSH IN ACROSS THE AREA BY EARLY
THURSDAY EVENING...AND THIS SHOULD BRING AN END TO THE
PRECIP...WITH THE EXCEPTION OF FAR NORTH CENTRAL ILLINOIS...WHERE
SOME RAP AROUND SNOW SHOWERS ARE POSSIBLE IN ASSOCIATION WITH THE
MID LEVEL DEFORMATION ZONE.
THE MAIN STORY THURSDAY EVENING...HOWEVER...WILL BE THE STRONG
SYNOPTIC WINDS IN THE WAKE OF THE COLD FRONT. THE TRACK OF THE
SURFACE LOW WILL PLACE NORTHERN ILLINOIS/NORTHWESTERN INDIANA IN A
VERY FAVORABLE LOCATION FOR VERY STRONG SYNOPTIC WINDS THURSDAY
EVENING. ISOBARIC PRESSURE RISES ON THE ORDER OF 14+ MB IN A 6 HOUR
PERIOD ARE EXPECTED TO OVERSPREAD THE AREA. THIS COULD LEAD TO TOP
OF THE CHANNEL TYPE MIXING FOR A FEW HOURS FOLLOWING THE THE COLD
FRONTAL PASSAGE EARLY THURSDAY EVENING. AS SUCH...THIS COULD LEAD TO
50+ KT WIND GUSTS ACROSS THE AREA FOR A PERIOD THURSDAY EVENING. IN
SPITE OF THIS...I WILL LET THE OVERNIGHT SHIFT GET ANOTHER LOOK AT
THIS POTENTIAL TO SEE IF EITHER A WIND ADVISORY OR HIGH WIND
WARNING WILL BE NEEDED FOR THIS PERIOD.
KJB
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...
300 PM...STRONG LOW PRESSURE OVER WISCONSIN WILL CONTINUE TO
DEEPEN THURSDAY NIGHT AS IT LIFTS NORTH TO LAKE SUPERIOR. THE
GRADIENT WILL REMAIN TIGHT THROUGH FRIDAY AFTERNOON WITH WESTERLY
WINDS 20-30 MPH WITH HIGHER GUSTS INTO THE 40 MPH RANGE. THERE
REMAINS A SMALL POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS LATE
THURSDAY NIGHT INTO EARLY FRIDAY MORNING MAINLY ACROSS THE NORTH
HALF/THIRD OF THE CWA. ANY AMOUNTS WILL BE LIGHT BUT WITH THE
CONTINUED STRONG WINDS...ANY FRESH SNOW WILL LIKELY CAUSE SOME
BLOWING/DRIFTING SNOW.
A WEAKER COLD FRONT/TROUGH WILL PASS ACROSS THE REGION FRIDAY
EVENING...BRINGING ANOTHER CHANCE OF LIGHT SNOW/SNOW SHOWERS AND
HAVE ADDED THIS TO THE FORECAST...BUT PRIOR TO ITS ARRIVAL...WEAK
WARM AIR ADVECTION WILL SPREAD ACROSS THE AREA WITH AT LEAST SOME
SUNSHINE THROUGH MIDDAY. HAVE BUMPED HIGH TEMPS UP A TAD INTO THE
MID/UPPER 30S ACROSS MUCH OF THE CWA BUT THIS IS STILL A FEW
DEGREES BELOW CURRENT GUIDANCE LEVELS AND MAY END UP BEING TOO
COOL.
COLDER AIR THEN SPREADS BACK ACROSS THE REGION THIS WEEKEND WITH
BELOW NORMAL/MUCH COLDER TEMPERATURES THROUGH THE MIDDLE OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 20S AND LOWS IN THE SINGLE DIGITS.
ECMWF/GFS HAVE BEEN SOMEWHAT CONSISTENT WITH A CLIPPER LIKE SYSTEM
MOVING ACROSS THE AREA MONDAY NIGHT WITH A TENTH OR TWO OF QPF.
THIS COULD EASILY FLUFF UP A FEW INCHES OF SNOW. HAVE MAINTAINED
GOING CHANCE POPS AS THE TREND HAS BEEN FOR IT TO SAG A LITTLE
FURTHER SOUTH AND PERHAPS AFFECT ONLY THE SOUTHERN PART OF THE CWA.
MODELS THAN DIFFER ON JUST HOW COLD THE NEXT PUNCH OF ARCTIC AIR
WILL BE WHEN IT ARRIVES WEDNESDAY/WEDNESDAY NIGHT. CMS
&&
.HYDROLOGY...
330 PM CST...THE STRONG LATE WINTER STORM SYSTEM IS EXPECTED TO
BRING CONDITIONS THAT WOULD BE CONDUCIVE TO THE POTENTIAL FOR
WIDESPREAD AREAL AND RIVER FLOODING TO NORTHERN ILLINOIS AND
NORTHWEST INDIANA.
PRECIPITATION IS EXPECTED TO BEGIN DURING THE EARLY MORNING HOURS
AND WILL INITIALLY BE A WINTRY MIX WITH LIGHT QPF AMOUNTS. THROUGH
THE MORNING AND INTO THE AFTERNOON...AS THE MAIN SFC LOW DEEPENS...
THE ASSOCIATED WARM FRONT WILL SURGE NORTH INTO WISCONSIN AND SET
UP A PERSISTENT FETCH OF WARM...MOIST AIR FROM A WIDE OPEN WESTERN
GLFMEX REGION. CURRENT INDICATORS SUGGEST THAT TEMPERATURES WILL
SURGE INTO THE UPPER 40S NEAR THE WISCONSIN BORDER TO THE MIDDLE
50S SOUTH OF THE ILLINOIS AND KANKAKEE RIVER VALLEYS. SFC
DEWPOINTS WILL ALSO SURGE INTO THE MIDDLE 40S TO AROUND 50F. THE
MODEL GUIDANCE SUGGESTS THAT PRECIPITABLE WATER VALUES WILL
APPROACH 1 INCH TOMORROW...WHICH IS AT LEAST 2 STANDARD DEVIATIONS
HIGHER THAN NORMAL FOR LATE FEBRUARY. THE HIGH PRECIPITABLE WATER
VALUES AND THE DYNAMIC SYSTEM ARE INDICATIVE THAT THE POTENTIAL
FOR A SIGNIFICANT AMOUNT OF LIQUID PRECIPITATION...WITH THE
CURRENT FORECAST CARRYING 0.75 TO 1.00 INCHES FOR THE PERIOD
FROM 09Z THURSDAY THROUGH 00Z FRIDAY. THE HEAVY RAIN WILL HAVE AN
IMPACT ON BOTH AREAL FLOOD AND RIVER FLOOD CONCERNS.
THE WARM...HIGH DEWPOINT AIR IS VERY EFFICIENT AT MELTING SNOW
AND...CURRENTLY...THERE IS 2 TO 4 INCHES OF LIQUID EQUIVALENT
TRAPPED IN THE SNOW PACK. THIS...COMBINED WITH AROUND 1 INCH OF
WIDESPREAD QPF...WOULD GIVE A WORST CASE SCENARIO OF 3 TO 5 INCHES
OF RAINFALL. HOWEVER...THERE ARE LIMITING AND COMPLICATING FACTORS
WHICH NEED TO PLAY OUT...WHICH WOULD ACT TO EITHER LIMIT THE FLOOD
POTENTIAL OR ENHANCE THE FLOOD POTENTIAL...ESPECIALLY FOR AREA
RIVERS. CURRENTLY...MOST AREA RIVERS AND STREAMS ARE EITHER TOTALLY
ICE COVERED OR ONLY HAVE VERY LIMITED AMOUNTS OF OPEN WATER...SINCE
THIS WINTER HAS SEEN AN UNUSUAL DEGREE OF EXTREME COLD. EVEN THE
ILLINOIS RIVER HAS MUCH MORE ICE COVERAGE THAN IS NORMALLY OBSERVED
IN A TYPICAL WINTER. HEAVY RAINFALL AND ICE COVERED RIVERS WILL
HAVE A TWO-FOLD IMPACT. THE CAPACITY OF ICE COVERED RIVERS IS MUCH
LOWER THAN OPEN RIVERS WITH THE RAIN COLLECTING ON TOP OF THE ICE AS
IT IT WERE A RIVER BED. SO...LESS RAINFALL WOULD BE NEEDED TO RAISE
WATER LEVELS ABOVE BANK FULL AND TO FLOOD STAGE. ALSO...THE RAINFALL
WILL INCREASE BASE FLOW AND INFILTRATION OF RAINFALL INTO THE
RIVERS...LEADING TO INCREASED STREAM FLOW RATES...INCREASING
HYDROSTATIC PRESSURE UNDER THE ICE...WHICH COULD THEN LEAD TO ICE
BREAKUP AND ICE JAM FLOODING. ANY ICE JAM FLOODING WOULD ONLY
COMPOUND ANY RIVER FLOODING CAUSED BY THE RAINFALL RUNNING OFF ON
TOP OF THE ICE. HOWEVER...SINCE THE FROST DEPTH IS AROUND 14 INCHES
ACROSS THE AREA...IT IS UNLIKELY THAT THE INFLUX OF WARM AIR AND
RAIN WILL HAVE A SIGNIFICANT IMPACT ON THE FROST DEPTH. SO...ANY
MELTING AND RAINFALL WILL LIKELY MOSTLY BECOME RUNOFF...RATHER THAN
BEING INCORPORATED INTO INCREASED BASE FLOW...SO THERE IS LESS OF A
THREAT FOR WIDESPREAD BREAKUP OF THE THICKER ICE. BUT THE
POSSIBILITY OF ICE BREAKUP AND ICE JAM FLOODING CAN NOT BE RULED OUT
FOR RIVERS WITH THINNER ICE COVERAGE. THERE IS ALSO SOME
UNCERTAINTY AS TO THE DEGREE OF SNOW MELT THAT CAN BE EXPECTED AND
THE ASSOCIATED IMPACT ON RIVER LEVELS. CURRENTLY...THE RIVER STAGE
MODELS HAVE BEEN RUN WITH THE PREMISE THAT THE SNOW PACK WILL NOT
COMPLETELY MELT...ESPECIALLY FOR THE NORTHERN PORTIONS OF THE CWA
WHICH HAVE A DEEPER SNOW PACK AND SHOULD BE COLDER FOR A LONGER
PERIOD OF TIME. THERE IS ALSO THE CONSIDERATION THAT THE SNOW PACK
WILL ABSORB SOME OF THE RAINFALL BEFORE IT IS CONVERTED INTO
RUNOFF. SO...ALL THINGS CONSIDERED...THERE WILL BE A SIGNIFICANT
CHANCE FOR RIVER FLOODING WITH MANY RIVERS REACHING OR EXCEEDING
BANK FULL...BUT MAJOR OR RECORD BREAKING RIVER STAGES IS NOT LIKELY.
FOR AREAL FLOODING...THE MAIN CONTRIBUTORS WILL BE THE HEAVY
RAINFALL AND MELTING SNOW. AGAIN...WITH THE FROST DEPTH OF 14
INCHES...IT IS UNLIKELY THAT THERE WILL BE SIGNIFICANT INFILTRATION
INTO THE GROUND AND SNOW MELT AND RAINFALL WILL COMBINE INTO RUNOFF.
HOWEVER...SIMILAR TO THE RIVER ISSUES...IT WILL BE TOUGH FOR ALL OF
THE SNOW PACK TO MELT AND SOME OF THE RAINFALL COULD BECOME TRAPPED
IN THE RESIDUAL SNOW PACK...WHICH WOULD IN TURN LOWER THE RUNOFF.
AT THIS POINT...FEEL THAT AREAL FLOODING WILL BE LIMITED TO FLOODING
OF LOW LYING AREAS...UNDERPASSES AND DITCHES ADJACENT TO ROADS.
ALSO...URBAN AND SUBURBAN AREAS COULD SEE WIDESPREAD AREAS OF
PONDING AND STANDING WATER DUE TO SNOW-CLOGGED STORM DRAINS.
FOR THE HEADLINES...WILL MAINTAIN THE GOING FLOOD WATCH AND MONITOR
CONDITIONS BEFORE EITHER GOING WITH A FLOOD WARNING OR AN URBAN AND
SMALL STREAM FLOOD ADVISORY. AS FOR AREA RIVERS...WILL WAIT UNTIL
THE NEXT MODEL RUNS FROM THE NCRFC BEFORE DECIDING ON HEADLINES FOR
AREA RIVERS. THE CURRENT RIVER FORECASTS DO CONSIDER THE
RAINFALL...BUT HAVE BEEN RUN WITH AN INITIAL CONDITION OF LIMITED
SNOW MELT. CHANGES IN THE INITIAL CONDITIONS FOR SNOW MELT AND QPF
WILL HAVE A SIGNIFICANT IMPACT ON THE RIVER STAGE FORECASTS.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* WARM FRONT LIFTING ACROSS THE REGION LATE OVERNIGHT WITH CIGS
QUICKLY DROPPING TO IFR AND PRECIPITATION...POSSIBLY A WINTRY
MIX...OVERSPREADING THE AREA.
* SHIFTING WINDS THROUGH THE DAY...BECOMING GUSTY IN THE
AFTERNOON...AND VERY GUSTY IN THE EVENING.
BMD
//DISCUSSION...UPDATED 00Z...
HIGH PRESSURE LIES OVER THE OHIO VALLEY THIS EVENING WITH A RIDGE
EXTENDING INTO THE LOWER LAKES REGION PROVIDING LIGHT FLOW AND VFR
CONDITIONS LOCALLY. QUIET WEATHER WILL PERSIST THROUGH SOME OF THE
OVERNIGHT HOURS...BUT LOW PRESSURE WILL DEEPEN OVER THE SOUTHERN
PLAINS OVERNIGHT WITH A WARMFRONT LIFTING ACROSS THE REGION AND
CONDITIONS QUICKLY DETERIORATING. A LEAD WAVE IS EXPECTED TO PASS
OVER THE REGION EARLY THURSDAY MORNING WITH THE COLUMN QUICKLY
SATURATING AND CIGS FALLING FROM ROUGHLY 100-120 AT 06Z...TO AROUND
015 BY 11Z. TEMPERATURES WILL BE KEY OVERNIGHT TO DETERMINING PRECIP
TYPE...AND UNFORTUNATELY THERE REMAINS CONSIDERABLE UNCERTAINTY EVEN
THIS CLOSE TO THE ONSET OF PRECIP. HAVE LEANED CLOSELY TOWARDS RAP
GUIDANCE WITH NAM SUGGESTING WARMER TEMPS AND A QUICKER TRANSITION
TO RAIN. THE RAP DOES SUGGEST A SHORT WINDOW OF SNOW...BUT
TEMPERATURES ALOFT WARM QUICKLY ON THE NOSE OF A 50+KT LOW LEVEL JET
AND EXPECT FULL MELTING OF PRECIP AS IT FALLS TO THE SURFACE.
SURFACE TEMPS THEN WILL BE THE DETERMINING FACTOR IN THE PERSISTENCE
OF THE ICE THREAT...AND GUIDANCE SHOWS A LOT OF VARIABILITY IN HOW
QUICKLY SURFACE TEMPS WILL RISE ABOVE FREEZING. MEANWHILE...CIGS
WILL CONTINUE TO FALL WITH THE SURFACE LOW TRACK ACROSS NORTH
CENTRAL ILLINOIS BY LATE AFTERNOON. DEWPOINTS RISING IN THE MID TO
UPPER 30S BY EARLY TO MID AFTERNOON OVER THE SNOWPACK WILL ALSO POSE
A THREAT FOR DENSE FOG TO DEVELOP...THOUGH IT IS UNCERTAIN HOW LOW
VSBY WILL GO. ANOTHER 40-50KT LLJ WILL ADVECT VERY MODEST
INSTABILITY OVERHEAD RESULTING THE THE THREAT FOR EMBEDDED
THUNDERSTORMS MID TO LATE AFTERNOON. WINDS WILL TURN WESTERLY BEHIND
THE DEPARTING LOW...WITH GUSTS TO OR IN EXCESS OF 40 KTS AT TIMES
POSSIBLE LATE IN THE EVENING AND OVERNIGHT.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE IN CIG TRENDS AND MEDIUM CONFIDENCE IN TIMING.
* LOW-MEDIUM CONFIDENCE IN WIND DIRECTION/SPEED.
* HIGH CONFIDENCE IN PRECIPITATION OVERSPREADING THE AREA THOUGH
LOW TO MEDIUM CONFIDENCE IN PTYPE AND TIMING POTENTIAL
TRANSITION TO ALL RAIN.
* LOW CONFIDENCE IN HOW DENSE FOG WILL BECOME.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...CHC SNOW OVERNIGHT.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHC SNOW OVERNIGHT.
TUESDAY...VFR.
BMD
&&
.MARINE...
315 PM...LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS
TONIGHT AND DEEPEN AS IT MOVES TO SOUTHERN WISCONSIN THURSDAY
EVENING. THIS LOW WILL THEN CONTINUE TO DEEPEN AS IT REACHES LAKE
SUPERIOR FRIDAY MORNING. SOUTHERLY WINDS WILL TURN SOUTHEAST
TONIGHT AND GRADUALLY INCREASE OVERNIGHT THEN TURN A BIT MORE
EAST/SOUTHEAST THURSDAY AS SPEEDS INCREASE TO 30 KTS MIDDAY. AS
THE LOW APPROACHES...GALES WILL DEVELOP LATE THURSDAY AFTERNOON.
ONCE THE LOW REACHES WISCONSIN...WINDS WILL SHIFT TO THE SOUTHWEST
AND STEADILY INCREASE THROUGH HIGH END GALES AND POTENTIALLY INTO
STORM FORCE. HAVE UPGRADED THE GALE WATCH TO A GALE WARNING AS
CONFIDENCE IS HIGH BUT MAINTAINED THE STORM WATCH FOR NOW. THE LOW
WILL WEAKEN SOME AS IT REACHES JAMES BAY BUT THEN BECOME NEARLY
STATIONARY WHICH WILL ALLOW A FAIRLY STRONG WESTERLY GRADIENT TO
CONTINUE INTO THIS WEEKEND WITH GALES ENDING ACROSS THE NORTH
FRIDAY NIGHT OR SATURDAY MORNING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...3 AM THURSDAY
TO 6 PM THURSDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...3 AM THURSDAY
TO 6 PM THURSDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM THURSDAY TO
MIDNIGHT FRIDAY.
STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 PM
THURSDAY TO 4 PM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
859 PM CST WED FEB 19 2014
.DISCUSSION...
303 PM CST
SHORT TERM...TONIGHT THROUGH THURSDAY PM...
A VERY DYNAMIC AND COMPLEX STORM SYSTEM WILL IMPACT THE AREA LATE
TONIGHT THROUGH THURSDAY EVENING. THIS WILL PRESENT A PLETHORA OF
FORECAST CONCERNS OVER THE NEXT 24 TO 36 HOURS. THESE INCLUDE:
1.) THE THREAT FOR ACCUMULATING SNOW AND ICE AT THE ONSET OVERNIGHT
TONIGHT...PARTICULARLY ACROSS FAR NORTHERN ILLINOIS ALONG AND NORTH
OF INTERSTATE 88.
2.)RAINFALL AMOUNTS AND HYDRO ISSUES ON THURSDAY.
3.)POTENTIAL FOR SOME STRONG THUNDERSTORMS THURSDAY AFTERNOON.
4.)POTENTIAL FOR AREAS OF FOG ON THURSDAY.
5.)THE SYNOPTIC WINDS ON THE BACK SIDE OF THE SYSTEM LATE THURSDAY
AFTERNOON AND INTO THURSDAY NIGHT.
THE 12 UTC GLOBAL MODELS HAVE THE BEST HANDLE ON THE EVOLUTION AND
TRACK OF THIS STORM SYSTEM OVER THE NEXT 36 HOURS. AS SUCH...THE 12
UTC NAM WAS A FAR EAST OUTLIER ON THE SURFACE LOW TRACK. IN MOST
CASES...THE 12 UTC NAM WAS A GOOD 100 TO 150 MILES EAST OF THE
GLOBAL MODELS AND ENSEMBLE SOLUTIONS...SO THE 12 UTC NAM WAS NOT
FOLLOWED.
OVERALL...CYCLOGENESIS WILL SET UP ACROSS THE FRONT RANGE OF THE
COLORADO ROCKIES THIS EVENING IN ASSOCIATION WITH A STOUT SHORT WAVE
DISTURBANCE...NOW PUSHING ACROSS THE INTER-MOUNTAIN WEST. THIS WILL
RESULT IN A SURFACE LOW AROUND 992 MB...WHICH SHOULD PUSH EASTWARD
ACROSS THE KANSAS OKLAHOMA STATE LINE OVERNIGHT. THE MID LEVEL
SYSTEM WILL BE FORCED TO BECOME NEGATIVELY TILTED AS IT ENCOUNTERS
RAPIDLY BUILDING HIGHS ACROSS THE GREAT LAKES REGION EARLY THURSDAY.
AS A RESULT...THE SURFACE LOW WILL DEVELOP EXPLOSIVELY...WITH THE
CENTRAL PRESSURE EXPECTED TO DROP NEARLY 12 MB IN 12 HOURS AS THE
LOW LIFTS NORTHEASTWARD TO SOUTHEASTERN WISCONSIN BY EARLY THURSDAY
EVENING. THE LOW WILL LIKELY CONTINUE DEEPENING TO AROUND 970 MB BY
FRIDAY MORNING AS IT MOVES ACROSS THE UPPER GREAT LAKES REGION.
THE RAPID DEEPENING OF THE CENTRAL PRESSURE OF THIS LOW ALONE SAYS
THAT THIS WILL BE A NOTABLE WEATHER MAKER FOR MUCH OF THE CENTRAL
CONUS. PRECIPITATION WILL LIKELY ONSET QUICKLY ACROSS MOST OF
ILLINOIS AND INTO INDIANA TONIGHT AFTER 1 OR 2 IN THE MORNING AS 45
TO 50 KT LOW LEVEL JET DEVELOPS AND NOSES INTO THE REGION. THIS WILL
SET UP A VERY IMPRESSIVE SURGE OF GULF MOISTURE...WITH PWATS QUICKLY
INCREASING FROM ONLY A TENTH OR TWO OF AN INCH...TWO AROUND 1 INCH
BY DAYBREAK THURSDAY. CLIMATOLOGICALLY SPEAKING...1 INCH PWATS THIS
TIME OF YEAR RANK IN THE 99 TH PERCENTILE...SO HEAVY RAINFALL WILL
DEFINITELY BE A CONCERN. FOR MORE INFO ON THE HYDRO...SEE THE HYDRO
DISCUSSION BELOW.
THERE CONTINUES TO BE CONCERNS OF A WINTER MIX OF SNOW...FREEZING
RAIN AND SLEET AT THE ONSET OF THE PRECIPITATION
OVERNIGHT...PARTICULARLY AREAS ALONG AND NORTH OF INTERSTATE 88. IT
APPEARS THAT STRONG DYNAMIC FORCING WILL SET UP ALONG THE NOSE OF
THE LOW LEVEL JET...AND THIS STRONG FORCING COMBINED WITH
EVAPORATION COOLING COULD RESULT IN A COLUMN COLD ENOUGH FOR ALL
SNOW...ESPECIALLY CLOSER TO THE WISCONSIN BOARDER. THIS COULD RESULT
IN A PERIOD OF MODERATE TO HEAVY SNOW AND SLEET ACROSS FAR NORTHERN
ILLINOIS TONIGHT INTO VERY EARLY THURSDAY MORNING BEFORE THE WARM
SURGE KICKS NORTHWARD...CHANGING EVERYTHING OVER TO LIQUID. MODEL
BUFFER SOUNDINGS ACROSS THIS REGION ARE VERY CONCERNING...WITH THE
PROFILES INDICATING A NEARLY ISOTHERMAL LAYER FROM THE SURFACE UP TO
AROUND 700 MB HUGGING THE FREEZING POINT...AND VERY STEEP MID LEVEL
LAPSE RATES ABOVE THIS ISOTHERMAL LAYER. SO ALTHOUGH THERE MAY ONLY
BE A COUPLE HOUR PERIOD SUPPORTIVE OF SNOW...SLEET AND FREEZING
RAIN...THERE COULD BE A FEW INCHES OF SNOW ACCUMULATION AND A FEW
HUNDREDTHS OF AN INCH OF ICE ACCUMULATION FAR NORTH PRIOR TO THE
CHANGE OVER TO RAIN...ESPECIALLY WITH ANY CONVECTIVE ELEMENTS.
CONFIDENCE REMAINS LOW...BUT I HAVE ADDED SOME SNOW AND ICE
ACCUMULATIONS INTO THE FORECAST...WITH THE POTENTIAL OF SOME RAPID
SNOW ACCUMULATIONS. I WILL HIGHLIGHT THIS THREAT IN AN SPS...AND
PASS ALONG THE CONCERNS TO THE EVENING SHIFT TO SEE IF ANY WINTER WX
HEADLINE WILL BE NEEDED.
ANY WINTER PRECIP WILL QUICKLY COME TO AN END EARLY THURSDAY
MORNING...WITH PERIODS OF RAIN AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING AS THE WARM FRONT SHIFTS ACROSS NORTHERN
ILLINOIS. IN ADDITION TO THE THUNDERSTORMS AND HEAVY RAIN
POTENTIAL...THERE IS A THREAT OF FOG...ESPECIALLY IN THE VICINITY
OF THE WARM FRONT AND SURFACE LOW. A STRONG COLD FRONT WILL BEGIN TO
PUSH ACROSS THE AREA DURING THE AFTERNOON...AND THIS LOOKS TO BE THE
FOCUS FOR A LINE OF STORMS. IT CURRENTLY APPEARS THE BETTER THREAT
FOR MORE WIDESPREAD SEVERE STORMS WILL BE SOUTH OF THE AREA. THE
EXTENSIVE SNOW PACK ACROSS THE AREA MAY RESULT IN A NEAR SURFACE
INVERSION THAT MAY KEEP THE STORMS FROM ROOTING THEMSELVES IN THE
BOUNDARY LAYER. BECAUSE OF THIS...ALTHOUGH THE WINDS WILL BE
SCREAMING UP OVER 50 KT OFF THE SURFACE...THEY MAY HAVE A HARD TIME
BEING FORCED TO THE GROUND WITH THE STORMS. THEREFORE...ALTHOUGH
SOME ISOLATED SEVERE WIND GUSTS ARE POSSIBLE WITH THESE AFTERNOON
SHOWERS/STORMS...IT APPEARS THE MORE WIDESPREAD ACTIVITY WILL REMAIN
SOUTH OF MUCH OF THE AREA.
A DRY MID LEVEL DRY SLOT WILL PUSH IN ACROSS THE AREA BY EARLY
THURSDAY EVENING...AND THIS SHOULD BRING AN END TO THE
PRECIP...WITH THE EXCEPTION OF FAR NORTH CENTRAL ILLINOIS...WHERE
SOME RAP AROUND SNOW SHOWERS ARE POSSIBLE IN ASSOCIATION WITH THE
MID LEVEL DEFORMATION ZONE.
THE MAIN STORY THURSDAY EVENING...HOWEVER...WILL BE THE STRONG
SYNOPTIC WINDS IN THE WAKE OF THE COLD FRONT. THE TRACK OF THE
SURFACE LOW WILL PLACE NORTHERN ILLINOIS/NORTHWESTERN INDIANA IN A
VERY FAVORABLE LOCATION FOR VERY STRONG SYNOPTIC WINDS THURSDAY
EVENING. ISOBARIC PRESSURE RISES ON THE ORDER OF 14+ MB IN A 6 HOUR
PERIOD ARE EXPECTED TO OVERSPREAD THE AREA. THIS COULD LEAD TO TOP
OF THE CHANNEL TYPE MIXING FOR A FEW HOURS FOLLOWING THE THE COLD
FRONTAL PASSAGE EARLY THURSDAY EVENING. AS SUCH...THIS COULD LEAD TO
50+ KT WIND GUSTS ACROSS THE AREA FOR A PERIOD THURSDAY EVENING. IN
SPITE OF THIS...I WILL LET THE OVERNIGHT SHIFT GET ANOTHER LOOK AT
THIS POTENTIAL TO SEE IF EITHER A WIND ADVISORY OR HIGH WIND
WARNING WILL BE NEEDED FOR THIS PERIOD.
KJB
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...
300 PM...STRONG LOW PRESSURE OVER WISCONSIN WILL CONTINUE TO
DEEPEN THURSDAY NIGHT AS IT LIFTS NORTH TO LAKE SUPERIOR. THE
GRADIENT WILL REMAIN TIGHT THROUGH FRIDAY AFTERNOON WITH WESTERLY
WINDS 20-30 MPH WITH HIGHER GUSTS INTO THE 40 MPH RANGE. THERE
REMAINS A SMALL POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS LATE
THURSDAY NIGHT INTO EARLY FRIDAY MORNING MAINLY ACROSS THE NORTH
HALF/THIRD OF THE CWA. ANY AMOUNTS WILL BE LIGHT BUT WITH THE
CONTINUED STRONG WINDS...ANY FRESH SNOW WILL LIKELY CAUSE SOME
BLOWING/DRIFTING SNOW.
A WEAKER COLD FRONT/TROUGH WILL PASS ACROSS THE REGION FRIDAY
EVENING...BRINGING ANOTHER CHANCE OF LIGHT SNOW/SNOW SHOWERS AND
HAVE ADDED THIS TO THE FORECAST...BUT PRIOR TO ITS ARRIVAL...WEAK
WARM AIR ADVECTION WILL SPREAD ACROSS THE AREA WITH AT LEAST SOME
SUNSHINE THROUGH MIDDAY. HAVE BUMPED HIGH TEMPS UP A TAD INTO THE
MID/UPPER 30S ACROSS MUCH OF THE CWA BUT THIS IS STILL A FEW
DEGREES BELOW CURRENT GUIDANCE LEVELS AND MAY END UP BEING TOO
COOL.
COLDER AIR THEN SPREADS BACK ACROSS THE REGION THIS WEEKEND WITH
BELOW NORMAL/MUCH COLDER TEMPERATURES THROUGH THE MIDDLE OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 20S AND LOWS IN THE SINGLE DIGITS.
ECMWF/GFS HAVE BEEN SOMEWHAT CONSISTENT WITH A CLIPPER LIKE SYSTEM
MOVING ACROSS THE AREA MONDAY NIGHT WITH A TENTH OR TWO OF QPF.
THIS COULD EASILY FLUFF UP A FEW INCHES OF SNOW. HAVE MAINTAINED
GOING CHANCE POPS AS THE TREND HAS BEEN FOR IT TO SAG A LITTLE
FURTHER SOUTH AND PERHAPS AFFECT ONLY THE SOUTHERN PART OF THE CWA.
MODELS THAN DIFFER ON JUST HOW COLD THE NEXT PUNCH OF ARCTIC AIR
WILL BE WHEN IT ARRIVES WEDNESDAY/WEDNESDAY NIGHT. CMS
&&
.HYDROLOGY...
330 PM CST...THE STRONG LATE WINTER STORM SYSTEM IS EXPECTED TO
BRING CONDITIONS THAT WOULD BE CONDUCIVE TO THE POTENTIAL FOR
WIDESPREAD AREAL AND RIVER FLOODING TO NORTHERN ILLINOIS AND
NORTHWEST INDIANA.
PRECIPITATION IS EXPECTED TO BEGIN DURING THE EARLY MORNING HOURS
AND WILL INITIALLY BE A WINTRY MIX WITH LIGHT QPF AMOUNTS. THROUGH
THE MORNING AND INTO THE AFTERNOON...AS THE MAIN SFC LOW DEEPENS...
THE ASSOCIATED WARM FRONT WILL SURGE NORTH INTO WISCONSIN AND SET
UP A PERSISTENT FETCH OF WARM...MOIST AIR FROM A WIDE OPEN WESTERN
GLFMEX REGION. CURRENT INDICATORS SUGGEST THAT TEMPERATURES WILL
SURGE INTO THE UPPER 40S NEAR THE WISCONSIN BORDER TO THE MIDDLE
50S SOUTH OF THE ILLINOIS AND KANKAKEE RIVER VALLEYS. SFC
DEWPOINTS WILL ALSO SURGE INTO THE MIDDLE 40S TO AROUND 50F. THE
MODEL GUIDANCE SUGGESTS THAT PRECIPITABLE WATER VALUES WILL
APPROACH 1 INCH TOMORROW...WHICH IS AT LEAST 2 STANDARD DEVIATIONS
HIGHER THAN NORMAL FOR LATE FEBRUARY. THE HIGH PRECIPITABLE WATER
VALUES AND THE DYNAMIC SYSTEM ARE INDICATIVE THAT THE POTENTIAL
FOR A SIGNIFICANT AMOUNT OF LIQUID PRECIPITATION...WITH THE
CURRENT FORECAST CARRYING 0.75 TO 1.00 INCHES FOR THE PERIOD
FROM 09Z THURSDAY THROUGH 00Z FRIDAY. THE HEAVY RAIN WILL HAVE AN
IMPACT ON BOTH AREAL FLOOD AND RIVER FLOOD CONCERNS.
THE WARM...HIGH DEWPOINT AIR IS VERY EFFICIENT AT MELTING SNOW
AND...CURRENTLY...THERE IS 2 TO 4 INCHES OF LIQUID EQUIVALENT
TRAPPED IN THE SNOW PACK. THIS...COMBINED WITH AROUND 1 INCH OF
WIDESPREAD QPF...WOULD GIVE A WORST CASE SCENARIO OF 3 TO 5 INCHES
OF RAINFALL. HOWEVER...THERE ARE LIMITING AND COMPLICATING FACTORS
WHICH NEED TO PLAY OUT...WHICH WOULD ACT TO EITHER LIMIT THE FLOOD
POTENTIAL OR ENHANCE THE FLOOD POTENTIAL...ESPECIALLY FOR AREA
RIVERS. CURRENTLY...MOST AREA RIVERS AND STREAMS ARE EITHER TOTALLY
ICE COVERED OR ONLY HAVE VERY LIMITED AMOUNTS OF OPEN WATER...SINCE
THIS WINTER HAS SEEN AN UNUSUAL DEGREE OF EXTREME COLD. EVEN THE
ILLINOIS RIVER HAS MUCH MORE ICE COVERAGE THAN IS NORMALLY OBSERVED
IN A TYPICAL WINTER. HEAVY RAINFALL AND ICE COVERED RIVERS WILL
HAVE A TWO-FOLD IMPACT. THE CAPACITY OF ICE COVERED RIVERS IS MUCH
LOWER THAN OPEN RIVERS WITH THE RAIN COLLECTING ON TOP OF THE ICE AS
IT IT WERE A RIVER BED. SO...LESS RAINFALL WOULD BE NEEDED TO RAISE
WATER LEVELS ABOVE BANK FULL AND TO FLOOD STAGE. ALSO...THE RAINFALL
WILL INCREASE BASE FLOW AND INFILTRATION OF RAINFALL INTO THE
RIVERS...LEADING TO INCREASED STREAM FLOW RATES...INCREASING
HYDROSTATIC PRESSURE UNDER THE ICE...WHICH COULD THEN LEAD TO ICE
BREAKUP AND ICE JAM FLOODING. ANY ICE JAM FLOODING WOULD ONLY
COMPOUND ANY RIVER FLOODING CAUSED BY THE RAINFALL RUNNING OFF ON
TOP OF THE ICE. HOWEVER...SINCE THE FROST DEPTH IS AROUND 14 INCHES
ACROSS THE AREA...IT IS UNLIKELY THAT THE INFLUX OF WARM AIR AND
RAIN WILL HAVE A SIGNIFICANT IMPACT ON THE FROST DEPTH. SO...ANY
MELTING AND RAINFALL WILL LIKELY MOSTLY BECOME RUNOFF...RATHER THAN
BEING INCORPORATED INTO INCREASED BASE FLOW...SO THERE IS LESS OF A
THREAT FOR WIDESPREAD BREAKUP OF THE THICKER ICE. BUT THE
POSSIBILITY OF ICE BREAKUP AND ICE JAM FLOODING CAN NOT BE RULED OUT
FOR RIVERS WITH THINNER ICE COVERAGE. THERE IS ALSO SOME
UNCERTAINTY AS TO THE DEGREE OF SNOW MELT THAT CAN BE EXPECTED AND
THE ASSOCIATED IMPACT ON RIVER LEVELS. CURRENTLY...THE RIVER STAGE
MODELS HAVE BEEN RUN WITH THE PREMISE THAT THE SNOW PACK WILL NOT
COMPLETELY MELT...ESPECIALLY FOR THE NORTHERN PORTIONS OF THE CWA
WHICH HAVE A DEEPER SNOW PACK AND SHOULD BE COLDER FOR A LONGER
PERIOD OF TIME. THERE IS ALSO THE CONSIDERATION THAT THE SNOW PACK
WILL ABSORB SOME OF THE RAINFALL BEFORE IT IS CONVERTED INTO
RUNOFF. SO...ALL THINGS CONSIDERED...THERE WILL BE A SIGNIFICANT
CHANCE FOR RIVER FLOODING WITH MANY RIVERS REACHING OR EXCEEDING
BANK FULL...BUT MAJOR OR RECORD BREAKING RIVER STAGES IS NOT LIKELY.
FOR AREAL FLOODING...THE MAIN CONTRIBUTORS WILL BE THE HEAVY
RAINFALL AND MELTING SNOW. AGAIN...WITH THE FROST DEPTH OF 14
INCHES...IT IS UNLIKELY THAT THERE WILL BE SIGNIFICANT INFILTRATION
INTO THE GROUND AND SNOW MELT AND RAINFALL WILL COMBINE INTO RUNOFF.
HOWEVER...SIMILAR TO THE RIVER ISSUES...IT WILL BE TOUGH FOR ALL OF
THE SNOW PACK TO MELT AND SOME OF THE RAINFALL COULD BECOME TRAPPED
IN THE RESIDUAL SNOW PACK...WHICH WOULD IN TURN LOWER THE RUNOFF.
AT THIS POINT...FEEL THAT AREAL FLOODING WILL BE LIMITED TO FLOODING
OF LOW LYING AREAS...UNDERPASSES AND DITCHES ADJACENT TO ROADS.
ALSO...URBAN AND SUBURBAN AREAS COULD SEE WIDESPREAD AREAS OF
PONDING AND STANDING WATER DUE TO SNOW-CLOGGED STORM DRAINS.
FOR THE HEADLINES...WILL MAINTAIN THE GOING FLOOD WATCH AND MONITOR
CONDITIONS BEFORE EITHER GOING WITH A FLOOD WARNING OR AN URBAN AND
SMALL STREAM FLOOD ADVISORY. AS FOR AREA RIVERS...WILL WAIT UNTIL
THE NEXT MODEL RUNS FROM THE NCRFC BEFORE DECIDING ON HEADLINES FOR
AREA RIVERS. THE CURRENT RIVER FORECASTS DO CONSIDER THE
RAINFALL...BUT HAVE BEEN RUN WITH AN INITIAL CONDITION OF LIMITED
SNOW MELT. CHANGES IN THE INITIAL CONDITIONS FOR SNOW MELT AND QPF
WILL HAVE A SIGNIFICANT IMPACT ON THE RIVER STAGE FORECASTS.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* WARM FRONT LIFTING ACROSS THE REGION LATE OVERNIGHT WITH CIGS
QUICKLY DROPPING TO IFR AND PRECIPITATION...POSSIBLY A WINTRY
MIX...OVERSPREADING THE AREA.
* SHIFTING WINDS THROUGH THE DAY...BECOMING GUSTY IN THE
AFTERNOON...AND VERY GUSTY IN THE EVENING.
BMD
//DISCUSSION...UPDATED 00Z...
HIGH PRESSURE LIES OVER THE OHIO VALLEY THIS EVENING WITH A RIDGE
EXTENDING INTO THE LOWER LAKES REGION PROVIDING LIGHT FLOW AND VFR
CONDITIONS LOCALLY. QUIET WEATHER WILL PERSIST THROUGH SOME OF THE
OVERNIGHT HOURS...BUT LOW PRESSURE WILL DEEPEN OVER THE SOUTHERN
PLAINS OVERNIGHT WITH A WARMFRONT LIFTING ACROSS THE REGION AND
CONDITIONS QUICKLY DETERIORATING. A LEAD WAVE IS EXPECTED TO PASS
OVER THE REGION EARLY THURSDAY MORNING WITH THE COLUMN QUICKLY
SATURATING AND CIGS FALLING FROM ROUGHLY 100-120 AT 06Z...TO AROUND
015 BY 11Z. TEMPERATURES WILL BE KEY OVERNIGHT TO DETERMINING PRECIP
TYPE...AND UNFORTUNATELY THERE REMAINS CONSIDERABLE UNCERTAINTY EVEN
THIS CLOSE TO THE ONSET OF PRECIP. HAVE LEANED CLOSELY TOWARDS RAP
GUIDANCE WITH NAM SUGGESTING WARMER TEMPS AND A QUICKER TRANSITION
TO RAIN. THE RAP DOES SUGGEST A SHORT WINDOW OF SNOW...BUT
TEMPERATURES ALOFT WARM QUICKLY ON THE NOSE OF A 50+KT LOW LEVEL JET
AND EXPECT FULL MELTING OF PRECIP AS IT FALLS TO THE SURFACE.
SURFACE TEMPS THEN WILL BE THE DETERMINING FACTOR IN THE PERSISTENCE
OF THE ICE THREAT...AND GUIDANCE SHOWS A LOT OF VARIABILITY IN HOW
QUICKLY SURFACE TEMPS WILL RISE ABOVE FREEZING. MEANWHILE...CIGS
WILL CONTINUE TO FALL WITH THE SURFACE LOW TRACK ACROSS NORTH
CENTRAL ILLINOIS BY LATE AFTERNOON. DEWPOINTS RISING IN THE MID TO
UPPER 30S BY EARLY TO MID AFTERNOON OVER THE SNOWPACK WILL ALSO POSE
A THREAT FOR DENSE FOG TO DEVELOP...THOUGH IT IS UNCERTAIN HOW LOW
VSBY WILL GO. ANOTHER 40-50KT LLJ WILL ADVECT VERY MODEST
INSTABILITY OVERHEAD RESULTING THE THE THREAT FOR EMBEDDED
THUNDERSTORMS MID TO LATE AFTERNOON. WINDS WILL TURN WESTERLY BEHIND
THE DEPARTING LOW...WITH GUSTS TO OR IN EXCESS OF 40 KTS AT TIMES
POSSIBLE LATE IN THE EVENING AND OVERNIGHT.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE IN CIG TRENDS AND MEDIUM CONFIDENCE IN TIMING.
* LOW-MEDIUM CONFIDENCE IN WIND DIRECTION/SPEED.
* HIGH CONFIDENCE IN PRECIPITATION OVERSPREADING THE AREA THOUGH
LOW TO MEDIUM CONFIDENCE IN PTYPE AND TIMING POTENTIAL
TRANSITION TO ALL RAIN.
* LOW CONFIDENCE IN HOW DENSE FOG WILL BECOME.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...CHC SNOW OVERNIGHT.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHC SNOW OVERNIGHT.
TUESDAY...VFR.
BMD
&&
.MARINE...
315 PM...LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS
TONIGHT AND DEEPEN AS IT MOVES TO SOUTHERN WISCONSIN THURSDAY
EVENING. THIS LOW WILL THEN CONTINUE TO DEEPEN AS IT REACHES LAKE
SUPERIOR FRIDAY MORNING. SOUTHERLY WINDS WILL TURN SOUTHEAST
TONIGHT AND GRADUALLY INCREASE OVERNIGHT THEN TURN A BIT MORE
EAST/SOUTHEAST THURSDAY AS SPEEDS INCREASE TO 30 KTS MIDDAY. AS
THE LOW APPROACHES...GALES WILL DEVELOP LATE THURSDAY AFTERNOON.
ONCE THE LOW REACHES WISCONSIN...WINDS WILL SHIFT TO THE SOUTHWEST
AND STEADILY INCREASE THROUGH HIGH END GALES AND POTENTIALLY INTO
STORM FORCE. HAVE UPGRADED THE GALE WATCH TO A GALE WARNING AS
CONFIDENCE IS HIGH BUT MAINTAINED THE STORM WATCH FOR NOW. THE LOW
WILL WEAKEN SOME AS IT REACHES JAMES BAY BUT THEN BECOME NEARLY
STATIONARY WHICH WILL ALLOW A FAIRLY STRONG WESTERLY GRADIENT TO
CONTINUE INTO THIS WEEKEND WITH GALES ENDING ACROSS THE NORTH
FRIDAY NIGHT OR SATURDAY MORNING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...3 AM THURSDAY
TO 6 PM THURSDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...3 AM THURSDAY
TO 6 PM THURSDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM THURSDAY TO
MIDNIGHT FRIDAY.
STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 PM
THURSDAY TO 4 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION...CORRECTED
NWS CHICAGO/ROMEOVILLE IL
621 PM CST WED FEB 19 2014
.DISCUSSION...
303 PM CST
SHORT TERM...TONIGHT THROUGH THURSDAY PM...
A VERY DYNAMIC AND COMPLEX STORM SYSTEM WILL IMPACT THE AREA LATE
TONIGHT THROUGH THURSDAY EVENING. THIS WILL PRESENT A PLETHORA OF
FORECAST CONCERNS OVER THE NEXT 24 TO 36 HOURS. THESE INCLUDE:
1.) THE THREAT FOR ACCUMULATING SNOW AND ICE AT THE ONSET OVERNIGHT
TONIGHT...PARTICULARLY ACROSS FAR NORTHERN ILLINOIS ALONG AND NORTH
OF INTERSTATE 88.
2.)RAINFALL AMOUNTS AND HYDRO ISSUES ON THURSDAY.
3.)POTENTIAL FOR SOME STRONG THUNDERSTORMS THURSDAY AFTERNOON.
4.)POTENTIAL FOR AREAS OF FOG ON THURSDAY.
5.)THE SYNOPTIC WINDS ON THE BACK SIDE OF THE SYSTEM LATE THURSDAY
AFTERNOON AND INTO THURSDAY NIGHT.
THE 12 UTC GLOBAL MODELS HAVE THE BEST HANDLE ON THE EVOLUTION AND
TRACK OF THIS STORM SYSTEM OVER THE NEXT 36 HOURS. AS SUCH...THE 12
UTC NAM WAS A FAR EAST OUTLIER ON THE SURFACE LOW TRACK. IN MOST
CASES...THE 12 UTC NAM WAS A GOOD 100 TO 150 MILES EAST OF THE
GLOBAL MODELS AND ENSEMBLE SOLUTIONS...SO THE 12 UTC NAM WAS NOT
FOLLOWED.
OVERALL...CYCLOGENESIS WILL SET UP ACROSS THE FRONT RANGE OF THE
COLORADO ROCKIES THIS EVENING IN ASSOCIATION WITH A STOUT SHORT WAVE
DISTURBANCE...NOW PUSHING ACROSS THE INTER-MOUNTAIN WEST. THIS WILL
RESULT IN A SURFACE LOW AROUND 992 MB...WHICH SHOULD PUSH EASTWARD
ACROSS THE KANSAS OKLAHOMA STATE LINE OVERNIGHT. THE MID LEVEL
SYSTEM WILL BE FORCED TO BECOME NEGATIVELY TILTED AS IT ENCOUNTERS
RAPIDLY BUILDING HIGHS ACROSS THE GREAT LAKES REGION EARLY THURSDAY.
AS A RESULT...THE SURFACE LOW WILL DEVELOP EXPLOSIVELY...WITH THE
CENTRAL PRESSURE EXPECTED TO DROP NEARLY 12 MB IN 12 HOURS AS THE
LOW LIFTS NORTHEASTWARD TO SOUTHEASTERN WISCONSIN BY EARLY THURSDAY
EVENING. THE LOW WILL LIKELY CONTINUE DEEPENING TO AROUND 970 MB BY
FRIDAY MORNING AS IT MOVES ACROSS THE UPPER GREAT LAKES REGION.
THE RAPID DEEPENING OF THE CENTRAL PRESSURE OF THIS LOW ALONE SAYS
THAT THIS WILL BE A NOTABLE WEATHER MAKER FOR MUCH OF THE CENTRAL
CONUS. PRECIPITATION WILL LIKELY ONSET QUICKLY ACROSS MOST OF
ILLINOIS AND INTO INDIANA TONIGHT AFTER 1 OR 2 IN THE MORNING AS 45
TO 50 KT LOW LEVEL JET DEVELOPS AND NOSES INTO THE REGION. THIS WILL
SET UP A VERY IMPRESSIVE SURGE OF GULF MOISTURE...WITH PWATS QUICKLY
INCREASING FROM ONLY A TENTH OR TWO OF AN INCH...TWO AROUND 1 INCH
BY DAYBREAK THURSDAY. CLIMATOLOGICALLY SPEAKING...1 INCH PWATS THIS
TIME OF YEAR RANK IN THE 99 TH PERCENTILE...SO HEAVY RAINFALL WILL
DEFINITELY BE A CONCERN. FOR MORE INFO ON THE HYDRO...SEE THE HYDRO
DISCUSSION BELOW.
THERE CONTINUES TO BE CONCERNS OF A WINTER MIX OF SNOW...FREEZING
RAIN AND SLEET AT THE ONSET OF THE PRECIPITATION
OVERNIGHT...PARTICULARLY AREAS ALONG AND NORTH OF INTERSTATE 88. IT
APPEARS THAT STRONG DYNAMIC FORCING WILL SET UP ALONG THE NOSE OF
THE LOW LEVEL JET...AND THIS STRONG FORCING COMBINED WITH
EVAPORATION COOLING COULD RESULT IN A COLUMN COLD ENOUGH FOR ALL
SNOW...ESPECIALLY CLOSER TO THE WISCONSIN BOARDER. THIS COULD RESULT
IN A PERIOD OF MODERATE TO HEAVY SNOW AND SLEET ACROSS FAR NORTHERN
ILLINOIS TONIGHT INTO VERY EARLY THURSDAY MORNING BEFORE THE WARM
SURGE KICKS NORTHWARD...CHANGING EVERYTHING OVER TO LIQUID. MODEL
BUFFER SOUNDINGS ACROSS THIS REGION ARE VERY CONCERNING...WITH THE
PROFILES INDICATING A NEARLY ISOTHERMAL LAYER FROM THE SURFACE UP TO
AROUND 700 MB HUGGING THE FREEZING POINT...AND VERY STEEP MID LEVEL
LAPSE RATES ABOVE THIS ISOTHERMAL LAYER. SO ALTHOUGH THERE MAY ONLY
BE A COUPLE HOUR PERIOD SUPPORTIVE OF SNOW...SLEET AND FREEZING
RAIN...THERE COULD BE A FEW INCHES OF SNOW ACCUMULATION AND A FEW
HUNDREDTHS OF AN INCH OF ICE ACCUMULATION FAR NORTH PRIOR TO THE
CHANGE OVER TO RAIN...ESPECIALLY WITH ANY CONVECTIVE ELEMENTS.
CONFIDENCE REMAINS LOW...BUT I HAVE ADDED SOME SNOW AND ICE
ACCUMULATIONS INTO THE FORECAST...WITH THE POTENTIAL OF SOME RAPID
SNOW ACCUMULATIONS. I WILL HIGHLIGHT THIS THREAT IN AN SPS...AND
PASS ALONG THE CONCERNS TO THE EVENING SHIFT TO SEE IF ANY WINTER WX
HEADLINE WILL BE NEEDED.
ANY WINTER PRECIP WILL QUICKLY COME TO AN END EARLY THURSDAY
MORNING...WITH PERIODS OF RAIN AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING AS THE WARM FRONT SHIFTS ACROSS NORTHERN
ILLINOIS. IN ADDITION TO THE THUNDERSTORMS AND HEAVY RAIN
POTENTIAL...THERE IS A THREAT OF FOG...ESPECIALLY IN THE VICINITY
OF THE WARM FRONT AND SURFACE LOW. A STRONG COLD FRONT WILL BEGIN TO
PUSH ACROSS THE AREA DURING THE AFTERNOON...AND THIS LOOKS TO BE THE
FOCUS FOR A LINE OF STORMS. IT CURRENTLY APPEARS THE BETTER THREAT
FOR MORE WIDESPREAD SEVERE STORMS WILL BE SOUTH OF THE AREA. THE
EXTENSIVE SNOW PACK ACROSS THE AREA MAY RESULT IN A NEAR SURFACE
INVERSION THAT MAY KEEP THE STORMS FROM ROOTING THEMSELVES IN THE
BOUNDARY LAYER. BECAUSE OF THIS...ALTHOUGH THE WINDS WILL BE
SCREAMING UP OVER 50 KT OFF THE SURFACE...THEY MAY HAVE A HARD TIME
BEING FORCED TO THE GROUND WITH THE STORMS. THEREFORE...ALTHOUGH
SOME ISOLATED SEVERE WIND GUSTS ARE POSSIBLE WITH THESE AFTERNOON
SHOWERS/STORMS...IT APPEARS THE MORE WIDESPREAD ACTIVITY WILL REMAIN
SOUTH OF MUCH OF THE AREA.
A DRY MID LEVEL DRY SLOT WILL PUSH IN ACROSS THE AREA BY EARLY
THURSDAY EVENING...AND THIS SHOULD BRING AN END TO THE
PRECIP...WITH THE EXCEPTION OF FAR NORTH CENTRAL ILLINOIS...WHERE
SOME RAP AROUND SNOW SHOWERS ARE POSSIBLE IN ASSOCIATION WITH THE
MID LEVEL DEFORMATION ZONE.
THE MAIN STORY THURSDAY EVENING...HOWEVER...WILL BE THE STRONG
SYNOPTIC WINDS IN THE WAKE OF THE COLD FRONT. THE TRACK OF THE
SURFACE LOW WILL PLACE NORTHERN ILLINOIS/NORTHWESTERN INDIANA IN A
VERY FAVORABLE LOCATION FOR VERY STRONG SYNOPTIC WINDS THURSDAY
EVENING. ISOBARIC PRESSURE RISES ON THE ORDER OF 14+ MB IN A 6 HOUR
PERIOD ARE EXPECTED TO OVERSPREAD THE AREA. THIS COULD LEAD TO TOP
OF THE CHANNEL TYPE MIXING FOR A FEW HOURS FOLLOWING THE THE COLD
FRONTAL PASSAGE EARLY THURSDAY EVENING. AS SUCH...THIS COULD LEAD TO
50+ KT WIND GUSTS ACROSS THE AREA FOR A PERIOD THURSDAY EVENING. IN
SPITE OF THIS...I WILL LET THE OVERNIGHT SHIFT GET ANOTHER LOOK AT
THIS POTENTIAL TO SEE IF EITHER A WIND ADVISORY OR HIGH WIND
WARNING WILL BE NEEDED FOR THIS PERIOD.
KJB
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...
300 PM...STRONG LOW PRESSURE OVER WISCONSIN WILL CONTINUE TO
DEEPEN THURSDAY NIGHT AS IT LIFTS NORTH TO LAKE SUPERIOR. THE
GRADIENT WILL REMAIN TIGHT THROUGH FRIDAY AFTERNOON WITH WESTERLY
WINDS 20-30 MPH WITH HIGHER GUSTS INTO THE 40 MPH RANGE. THERE
REMAINS A SMALL POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS LATE
THURSDAY NIGHT INTO EARLY FRIDAY MORNING MAINLY ACROSS THE NORTH
HALF/THIRD OF THE CWA. ANY AMOUNTS WILL BE LIGHT BUT WITH THE
CONTINUED STRONG WINDS...ANY FRESH SNOW WILL LIKELY CAUSE SOME
BLOWING/DRIFTING SNOW.
A WEAKER COLD FRONT/TROUGH WILL PASS ACROSS THE REGION FRIDAY
EVENING...BRINGING ANOTHER CHANCE OF LIGHT SNOW/SNOW SHOWERS AND
HAVE ADDED THIS TO THE FORECAST...BUT PRIOR TO ITS ARRIVAL...WEAK
WARM AIR ADVECTION WILL SPREAD ACROSS THE AREA WITH AT LEAST SOME
SUNSHINE THROUGH MIDDAY. HAVE BUMPED HIGH TEMPS UP A TAD INTO THE
MID/UPPER 30S ACROSS MUCH OF THE CWA BUT THIS IS STILL A FEW
DEGREES BELOW CURRENT GUIDANCE LEVELS AND MAY END UP BEING TOO
COOL.
COLDER AIR THEN SPREADS BACK ACROSS THE REGION THIS WEEKEND WITH
BELOW NORMAL/MUCH COLDER TEMPERATURES THROUGH THE MIDDLE OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 20S AND LOWS IN THE SINGLE DIGITS.
ECMWF/GFS HAVE BEEN SOMEWHAT CONSISTENT WITH A CLIPPER LIKE SYSTEM
MOVING ACROSS THE AREA MONDAY NIGHT WITH A TENTH OR TWO OF QPF.
THIS COULD EASILY FLUFF UP A FEW INCHES OF SNOW. HAVE MAINTAINED
GOING CHANCE POPS AS THE TREND HAS BEEN FOR IT TO SAG A LITTLE
FURTHER SOUTH AND PERHAPS AFFECT ONLY THE SOUTHERN PART OF THE CWA.
MODELS THAN DIFFER ON JUST HOW COLD THE NEXT PUNCH OF ARCTIC AIR
WILL BE WHEN IT ARRIVES WEDNESDAY/WEDNESDAY NIGHT. CMS
&&
.HYDROLOGY...
330 PM CST...THE STRONG LATE WINTER STORM SYSTEM IS EXPECTED TO
BRING CONDITIONS THAT WOULD BE CONDUCIVE TO THE POTENTIAL FOR
WIDESPREAD AREAL AND RIVER FLOODING TO NORTHERN ILLINOIS AND
NORTHWEST INDIANA.
PRECIPITATION IS EXPECTED TO BEGIN DURING THE EARLY MORNING HOURS
AND WILL INITIALLY BE A WINTRY MIX WITH LIGHT QPF AMOUNTS. THROUGH
THE MORNING AND INTO THE AFTERNOON...AS THE MAIN SFC LOW DEEPENS...
THE ASSOCIATED WARM FRONT WILL SURGE NORTH INTO WISCONSIN AND SET
UP A PERSISTENT FETCH OF WARM...MOIST AIR FROM A WIDE OPEN WESTERN
GLFMEX REGION. CURRENT INDICATORS SUGGEST THAT TEMPERATURES WILL
SURGE INTO THE UPPER 40S NEAR THE WISCONSIN BORDER TO THE MIDDLE
50S SOUTH OF THE ILLINOIS AND KANKAKEE RIVER VALLEYS. SFC
DEWPOINTS WILL ALSO SURGE INTO THE MIDDLE 40S TO AROUND 50F. THE
MODEL GUIDANCE SUGGESTS THAT PRECIPITABLE WATER VALUES WILL
APPROACH 1 INCH TOMORROW...WHICH IS AT LEAST 2 STANDARD DEVIATIONS
HIGHER THAN NORMAL FOR LATE FEBRUARY. THE HIGH PRECIPITABLE WATER
VALUES AND THE DYNAMIC SYSTEM ARE INDICATIVE THAT THE POTENTIAL
FOR A SIGNIFICANT AMOUNT OF LIQUID PRECIPITATION...WITH THE
CURRENT FORECAST CARRYING 0.75 TO 1.00 INCHES FOR THE PERIOD
FROM 09Z THURSDAY THROUGH 00Z FRIDAY. THE HEAVY RAIN WILL HAVE AN
IMPACT ON BOTH AREAL FLOOD AND RIVER FLOOD CONCERNS.
THE WARM...HIGH DEWPOINT AIR IS VERY EFFICIENT AT MELTING SNOW
AND...CURRENTLY...THERE IS 2 TO 4 INCHES OF LIQUID EQUIVALENT
TRAPPED IN THE SNOW PACK. THIS...COMBINED WITH AROUND 1 INCH OF
WIDESPREAD QPF...WOULD GIVE A WORST CASE SCENARIO OF 3 TO 5 INCHES
OF RAINFALL. HOWEVER...THERE ARE LIMITING AND COMPLICATING FACTORS
WHICH NEED TO PLAY OUT...WHICH WOULD ACT TO EITHER LIMIT THE FLOOD
POTENTIAL OR ENHANCE THE FLOOD POTENTIAL...ESPECIALLY FOR AREA
RIVERS. CURRENTLY...MOST AREA RIVERS AND STREAMS ARE EITHER TOTALLY
ICE COVERED OR ONLY HAVE VERY LIMITED AMOUNTS OF OPEN WATER...SINCE
THIS WINTER HAS SEEN AN UNUSUAL DEGREE OF EXTREME COLD. EVEN THE
ILLINOIS RIVER HAS MUCH MORE ICE COVERAGE THAN IS NORMALLY OBSERVED
IN A TYPICAL WINTER. HEAVY RAINFALL AND ICE COVERED RIVERS WILL
HAVE A TWO-FOLD IMPACT. THE CAPACITY OF ICE COVERED RIVERS IS MUCH
LOWER THAN OPEN RIVERS WITH THE RAIN COLLECTING ON TOP OF THE ICE AS
IT IT WERE A RIVER BED. SO...LESS RAINFALL WOULD BE NEEDED TO RAISE
WATER LEVELS ABOVE BANK FULL AND TO FLOOD STAGE. ALSO...THE RAINFALL
WILL INCREASE BASE FLOW AND INFILTRATION OF RAINFALL INTO THE
RIVERS...LEADING TO INCREASED STREAM FLOW RATES...INCREASING
HYDROSTATIC PRESSURE UNDER THE ICE...WHICH COULD THEN LEAD TO ICE
BREAKUP AND ICE JAM FLOODING. ANY ICE JAM FLOODING WOULD ONLY
COMPOUND ANY RIVER FLOODING CAUSED BY THE RAINFALL RUNNING OFF ON
TOP OF THE ICE. HOWEVER...SINCE THE FROST DEPTH IS AROUND 14 INCHES
ACROSS THE AREA...IT IS UNLIKELY THAT THE INFLUX OF WARM AIR AND
RAIN WILL HAVE A SIGNIFICANT IMPACT ON THE FROST DEPTH. SO...ANY
MELTING AND RAINFALL WILL LIKELY MOSTLY BECOME RUNOFF...RATHER THAN
BEING INCORPORATED INTO INCREASED BASE FLOW...SO THERE IS LESS OF A
THREAT FOR WIDESPREAD BREAKUP OF THE THICKER ICE. BUT THE
POSSIBILITY OF ICE BREAKUP AND ICE JAM FLOODING CAN NOT BE RULED OUT
FOR RIVERS WITH THINNER ICE COVERAGE. THERE IS ALSO SOME
UNCERTAINTY AS TO THE DEGREE OF SNOW MELT THAT CAN BE EXPECTED AND
THE ASSOCIATED IMPACT ON RIVER LEVELS. CURRENTLY...THE RIVER STAGE
MODELS HAVE BEEN RUN WITH THE PREMISE THAT THE SNOW PACK WILL NOT
COMPLETELY MELT...ESPECIALLY FOR THE NORTHERN PORTIONS OF THE CWA
WHICH HAVE A DEEPER SNOW PACK AND SHOULD BE COLDER FOR A LONGER
PERIOD OF TIME. THERE IS ALSO THE CONSIDERATION THAT THE SNOW PACK
WILL ABSORB SOME OF THE RAINFALL BEFORE IT IS CONVERTED INTO
RUNOFF. SO...ALL THINGS CONSIDERED...THERE WILL BE A SIGNIFICANT
CHANCE FOR RIVER FLOODING WITH MANY RIVERS REACHING OR EXCEEDING
BANK FULL...BUT MAJOR OR RECORD BREAKING RIVER STAGES IS NOT LIKELY.
FOR AREAL FLOODING...THE MAIN CONTRIBUTORS WILL BE THE HEAVY
RAINFALL AND MELTING SNOW. AGAIN...WITH THE FROST DEPTH OF 14
INCHES...IT IS UNLIKELY THAT THERE WILL BE SIGNIFICANT INFILTRATION
INTO THE GROUND AND SNOW MELT AND RAINFALL WILL COMBINE INTO RUNOFF.
HOWEVER...SIMILAR TO THE RIVER ISSUES...IT WILL BE TOUGH FOR ALL OF
THE SNOW PACK TO MELT AND SOME OF THE RAINFALL COULD BECOME TRAPPED
IN THE RESIDUAL SNOW PACK...WHICH WOULD IN TURN LOWER THE RUNOFF.
AT THIS POINT...FEEL THAT AREAL FLOODING WILL BE LIMITED TO FLOODING
OF LOW LYING AREAS...UNDERPASSES AND DITCHES ADJACENT TO ROADS.
ALSO...URBAN AND SUBURBAN AREAS COULD SEE WIDESPREAD AREAS OF
PONDING AND STANDING WATER DUE TO SNOW-CLOGGED STORM DRAINS.
FOR THE HEADLINES...WILL MAINTAIN THE GOING FLOOD WATCH AND MONITOR
CONDITIONS BEFORE EITHER GOING WITH A FLOOD WARNING OR AN URBAN AND
SMALL STREAM FLOOD ADVISORY. AS FOR AREA RIVERS...WILL WAIT UNTIL
THE NEXT MODEL RUNS FROM THE NCRFC BEFORE DECIDING ON HEADLINES FOR
AREA RIVERS. THE CURRENT RIVER FORECASTS DO CONSIDER THE
RAINFALL...BUT HAVE BEEN RUN WITH AN INITIAL CONDITION OF LIMITED
SNOW MELT. CHANGES IN THE INITIAL CONDITIONS FOR SNOW MELT AND QPF
WILL HAVE A SIGNIFICANT IMPACT ON THE RIVER STAGE FORECASTS.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* WARM FRONT LIFTING ACROSS THE REGION LATE OVERNIGHT WITH CIGS
QUICKLY DROPPING TO IFR AND PRECIPITATION...POSSIBLY A WINTRY
MIX...OVERSPREADING THE AREA.
* SHIFTING WINDS THROUGH THE DAY...BECOMING GUSTY IN THE
AFTERNOON...AND VERY GUSTY IN THE EVENING.
BMD
//DISCUSSION...UPDATED 00Z...
HIGH PRESSURE LIES OVER THE OHIO VALLEY THIS EVENING WITH A RIDGE
EXTENDING INTO THE LOWER LAKES REGION PROVIDING LIGHT FLOW AND VFR
CONDITIONS LOCALLY. QUIET WEATHER WILL PERSIST THROUGH SOME OF THE
OVERNIGHT HOURS...BUT LOW PRESSURE WILL DEEPEN OVER THE SOUTHERN
PLAINS OVERNIGHT WITH A WARMFRONT LIFTING ACROSS THE REGION AND
CONDITIONS QUICKLY DETERIORATING. A LEAD WAVE IS EXPECTED TO PASS
OVER THE REGION EARLY THURSDAY MORNING WITH THE COLUMN QUICKLY
SATURATING AND CIGS FALLING FROM ROUGHLY 100-120 AT 06Z...TO AROUND
015 BY 11Z. TEMPERATURES WILL BE KEY OVERNIGHT TO DETERMINING PRECIP
TYPE...AND UNFORTUNATELY THERE REMAINS CONSIDERABLE UNCERTAINTY EVEN
THIS CLOSE TO THE ONSET OF PRECIP. HAVE LEANED CLOSELY TOWARDS RAP
GUIDANCE WITH NAM SUGGESTING WARMER TEMPS AND A QUICKER TRANSITION
TO RAIN. THE RAP DOES SUGGEST A SHORT WINDOW OF SNOW...BUT
TEMPERATURES ALOFT WARM QUICKLY ON THE NOSE OF A 50+KT LOW LEVEL JET
AND EXPECT FULL MELTING OF PRECIP AS IT FALLS TO THE SURFACE.
SURFACE TEMPS THEN WILL BE THE DETERMINING FACTOR IN THE PERSISTENCE
OF THE ICE THREAT...AND GUIDANCE SHOWS A LOT OF VARIABILITY IN HOW
QUICKLY SURFACE TEMPS WILL RISE ABOVE FREEZING. MEANWHILE...CIGS
WILL CONTINUE TO FALL WITH THE SURFACE LOW TRACK ACROSS NORTH
CENTRAL ILLINOIS BY LATE AFTERNOON. DEWPOINTS RISING IN THE MID TO
UPPER 30S BY EARLY TO MID AFTERNOON OVER THE SNOWPACK WILL ALSO POSE
A THREAT FOR DENSE FOG TO DEVELOP...THOUGH IT IS UNCERTAIN HOW LOW
VSBY WILL GO. ANOTHER 40-50KT LLJ WILL ADVECT VERY MODEST
INSTABILITY OVERHEAD RESULTING THE THE THREAT FOR EMBEDDED
THUNDERSTORMS MID TO LATE AFTERNOON. WINDS WILL TURN WESTERLY BEHIND
THE DEPARTING LOW...WITH GUSTS TO OR IN EXCESS OF 40 KTS AT TIMES
POSSIBLE LATE IN THE EVENING AND OVERNIGHT.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE IN CIG TRENDS AND MEDIUM CONFIDENCE IN TIMING.
* LOW-MEDIUM CONFIDENCE IN WIND DIRECTION/SPEED.
* HIGH CONFIDENCE IN PRECIPITATION OVERSPREADING THE AREA THOUGH
LOW TO MEDIUM CONFIDENCE IN PTYPE AND TIMING POTENTIAL
TRANSITION TO ALL RAIN.
* LOW CONFIDENCE IN HOW DENSE FOG WILL BECOME.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...CHC SNOW OVERNIGHT.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHC SNOW OVERNIGHT.
TUESDAY...VFR.
BMD
&&
.MARINE...
315 PM...LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS
TONIGHT AND DEEPEN AS IT MOVES TO SOUTHERN WISCONSIN THURSDAY
EVENING. THIS LOW WILL THEN CONTINUE TO DEEPEN AS IT REACHES LAKE
SUPERIOR FRIDAY MORNING. SOUTHERLY WINDS WILL TURN SOUTHEAST
TONIGHT AND GRADUALLY INCREASE OVERNIGHT THEN TURN A BIT MORE
EAST/SOUTHEAST THURSDAY AS SPEEDS INCREASE TO 30 KTS MIDDAY. AS
THE LOW APPROACHES...GALES WILL DEVELOP LATE THURSDAY AFTERNOON.
ONCE THE LOW REACHES WISCONSIN...WINDS WILL SHIFT TO THE SOUTHWEST
AND STEADILY INCREASE THROUGH HIGH END GALES AND POTENTIALLY INTO
STORM FORCE. HAVE UPGRADED THE GALE WATCH TO A GALE WARNING AS
CONFIDENCE IS HIGH BUT MAINTAINED THE STORM WATCH FOR NOW. THE LOW
WILL WEAKEN SOME AS IT REACHES JAMES BAY BUT THEN BECOME NEARLY
STATIONARY WHICH WILL ALLOW A FAIRLY STRONG WESTERLY GRADIENT TO
CONTINUE INTO THIS WEEKEND WITH GALES ENDING ACROSS THE NORTH
FRIDAY NIGHT OR SATURDAY MORNING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...3 AM THURSDAY
TO 6 PM THURSDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...3 AM THURSDAY
TO 6 PM THURSDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM THURSDAY TO
MIDNIGHT FRIDAY.
STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 PM
THURSDAY TO 4 PM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
610 PM CST WED FEB 19 2014
.DISCUSSION...
303 PM CST
SHORT TERM...TONIGHT THROUGH THURSDAY PM...
A VERY DYNAMIC AND COMPLEX STORM SYSTEM WILL IMPACT THE AREA LATE
TONIGHT THROUGH THURSDAY EVENING. THIS WILL PRESENT A PLETHORA OF
FORECAST CONCERNS OVER THE NEXT 24 TO 36 HOURS. THESE INCLUDE:
1.) THE THREAT FOR ACCUMULATING SNOW AND ICE AT THE ONSET OVERNIGHT
TONIGHT...PARTICULARLY ACROSS FAR NORTHERN ILLINOIS ALONG AND NORTH
OF INTERSTATE 88.
2.)RAINFALL AMOUNTS AND HYDRO ISSUES ON THURSDAY.
3.)POTENTIAL FOR SOME STRONG THUNDERSTORMS THURSDAY AFTERNOON.
4.)POTENTIAL FOR AREAS OF FOG ON THURSDAY.
5.)THE SYNOPTIC WINDS ON THE BACK SIDE OF THE SYSTEM LATE THURSDAY
AFTERNOON AND INTO THURSDAY NIGHT.
THE 12 UTC GLOBAL MODELS HAVE THE BEST HANDLE ON THE EVOLUTION AND
TRACK OF THIS STORM SYSTEM OVER THE NEXT 36 HOURS. AS SUCH...THE 12
UTC NAM WAS A FAR EAST OUTLIER ON THE SURFACE LOW TRACK. IN MOST
CASES...THE 12 UTC NAM WAS A GOOD 100 TO 150 MILES EAST OF THE
GLOBAL MODELS AND ENSEMBLE SOLUTIONS...SO THE 12 UTC NAM WAS NOT
FOLLOWED.
OVERALL...CYCLOGENESIS WILL SET UP ACROSS THE FRONT RANGE OF THE
COLORADO ROCKIES THIS EVENING IN ASSOCIATION WITH A STOUT SHORT WAVE
DISTURBANCE...NOW PUSHING ACROSS THE INTER-MOUNTAIN WEST. THIS WILL
RESULT IN A SURFACE LOW AROUND 992 MB...WHICH SHOULD PUSH EASTWARD
ACROSS THE KANSAS OKLAHOMA STATE LINE OVERNIGHT. THE MID LEVEL
SYSTEM WILL BE FORCED TO BECOME NEGATIVELY TILTED AS IT ENCOUNTERS
RAPIDLY BUILDING HIGHS ACROSS THE GREAT LAKES REGION EARLY THURSDAY.
AS A RESULT...THE SURFACE LOW WILL DEVELOP EXPLOSIVELY...WITH THE
CENTRAL PRESSURE EXPECTED TO DROP NEARLY 12 MB IN 12 HOURS AS THE
LOW LIFTS NORTHEASTWARD TO SOUTHEASTERN WISCONSIN BY EARLY THURSDAY
EVENING. THE LOW WILL LIKELY CONTINUE DEEPENING TO AROUND 970 MB BY
FRIDAY MORNING AS IT MOVES ACROSS THE UPPER GREAT LAKES REGION.
THE RAPID DEEPENING OF THE CENTRAL PRESSURE OF THIS LOW ALONE SAYS
THAT THIS WILL BE A NOTABLE WEATHER MAKER FOR MUCH OF THE CENTRAL
CONUS. PRECIPITATION WILL LIKELY ONSET QUICKLY ACROSS MOST OF
ILLINOIS AND INTO INDIANA TONIGHT AFTER 1 OR 2 IN THE MORNING AS 45
TO 50 KT LOW LEVEL JET DEVELOPS AND NOSES INTO THE REGION. THIS WILL
SET UP A VERY IMPRESSIVE SURGE OF GULF MOISTURE...WITH PWATS QUICKLY
INCREASING FROM ONLY A TENTH OR TWO OF AN INCH...TWO AROUND 1 INCH
BY DAYBREAK THURSDAY. CLIMATOLOGICALLY SPEAKING...1 INCH PWATS THIS
TIME OF YEAR RANK IN THE 99 TH PERCENTILE...SO HEAVY RAINFALL WILL
DEFINITELY BE A CONCERN. FOR MORE INFO ON THE HYDRO...SEE THE HYDRO
DISCUSSION BELOW.
THERE CONTINUES TO BE CONCERNS OF A WINTER MIX OF SNOW...FREEZING
RAIN AND SLEET AT THE ONSET OF THE PRECIPITATION
OVERNIGHT...PARTICULARLY AREAS ALONG AND NORTH OF INTERSTATE 88. IT
APPEARS THAT STRONG DYNAMIC FORCING WILL SET UP ALONG THE NOSE OF
THE LOW LEVEL JET...AND THIS STRONG FORCING COMBINED WITH
EVAPORATION COOLING COULD RESULT IN A COLUMN COLD ENOUGH FOR ALL
SNOW...ESPECIALLY CLOSER TO THE WISCONSIN BOARDER. THIS COULD RESULT
IN A PERIOD OF MODERATE TO HEAVY SNOW AND SLEET ACROSS FAR NORTHERN
ILLINOIS TONIGHT INTO VERY EARLY THURSDAY MORNING BEFORE THE WARM
SURGE KICKS NORTHWARD...CHANGING EVERYTHING OVER TO LIQUID. MODEL
BUFFER SOUNDINGS ACROSS THIS REGION ARE VERY CONCERNING...WITH THE
PROFILES INDICATING A NEARLY ISOTHERMAL LAYER FROM THE SURFACE UP TO
AROUND 700 MB HUGGING THE FREEZING POINT...AND VERY STEEP MID LEVEL
LAPSE RATES ABOVE THIS ISOTHERMAL LAYER. SO ALTHOUGH THERE MAY ONLY
BE A COUPLE HOUR PERIOD SUPPORTIVE OF SNOW...SLEET AND FREEZING
RAIN...THERE COULD BE A FEW INCHES OF SNOW ACCUMULATION AND A FEW
HUNDREDTHS OF AN INCH OF ICE ACCUMULATION FAR NORTH PRIOR TO THE
CHANGE OVER TO RAIN...ESPECIALLY WITH ANY CONVECTIVE ELEMENTS.
CONFIDENCE REMAINS LOW...BUT I HAVE ADDED SOME SNOW AND ICE
ACCUMULATIONS INTO THE FORECAST...WITH THE POTENTIAL OF SOME RAPID
SNOW ACCUMULATIONS. I WILL HIGHLIGHT THIS THREAT IN AN SPS...AND
PASS ALONG THE CONCERNS TO THE EVENING SHIFT TO SEE IF ANY WINTER WX
HEADLINE WILL BE NEEDED.
ANY WINTER PRECIP WILL QUICKLY COME TO AN END EARLY THURSDAY
MORNING...WITH PERIODS OF RAIN AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING AS THE WARM FRONT SHIFTS ACROSS NORTHERN
ILLINOIS. IN ADDITION TO THE THUNDERSTORMS AND HEAVY RAIN
POTENTIAL...THERE IS A THREAT OF FOG...ESPECIALLY IN THE VICINITY
OF THE WARM FRONT AND SURFACE LOW. A STRONG COLD FRONT WILL BEGIN TO
PUSH ACROSS THE AREA DURING THE AFTERNOON...AND THIS LOOKS TO BE THE
FOCUS FOR A LINE OF STORMS. IT CURRENTLY APPEARS THE BETTER THREAT
FOR MORE WIDESPREAD SEVERE STORMS WILL BE SOUTH OF THE AREA. THE
EXTENSIVE SNOW PACK ACROSS THE AREA MAY RESULT IN A NEAR SURFACE
INVERSION THAT MAY KEEP THE STORMS FROM ROOTING THEMSELVES IN THE
BOUNDARY LAYER. BECAUSE OF THIS...ALTHOUGH THE WINDS WILL BE
SCREAMING UP OVER 50 KT OFF THE SURFACE...THEY MAY HAVE A HARD TIME
BEING FORCED TO THE GROUND WITH THE STORMS. THEREFORE...ALTHOUGH
SOME ISOLATED SEVERE WIND GUSTS ARE POSSIBLE WITH THESE AFTERNOON
SHOWERS/STORMS...IT APPEARS THE MORE WIDESPREAD ACTIVITY WILL REMAIN
SOUTH OF MUCH OF THE AREA.
A DRY MID LEVEL DRY SLOT WILL PUSH IN ACROSS THE AREA BY EARLY
THURSDAY EVENING...AND THIS SHOULD BRING AN END TO THE
PRECIP...WITH THE EXCEPTION OF FAR NORTH CENTRAL ILLINOIS...WHERE
SOME RAP AROUND SNOW SHOWERS ARE POSSIBLE IN ASSOCIATION WITH THE
MID LEVEL DEFORMATION ZONE.
THE MAIN STORY THURSDAY EVENING...HOWEVER...WILL BE THE STRONG
SYNOPTIC WINDS IN THE WAKE OF THE COLD FRONT. THE TRACK OF THE
SURFACE LOW WILL PLACE NORTHERN ILLINOIS/NORTHWESTERN INDIANA IN A
VERY FAVORABLE LOCATION FOR VERY STRONG SYNOPTIC WINDS THURSDAY
EVENING. ISOBARIC PRESSURE RISES ON THE ORDER OF 14+ MB IN A 6 HOUR
PERIOD ARE EXPECTED TO OVERSPREAD THE AREA. THIS COULD LEAD TO TOP
OF THE CHANNEL TYPE MIXING FOR A FEW HOURS FOLLOWING THE THE COLD
FRONTAL PASSAGE EARLY THURSDAY EVENING. AS SUCH...THIS COULD LEAD TO
50+ KT WIND GUSTS ACROSS THE AREA FOR A PERIOD THURSDAY EVENING. IN
SPITE OF THIS...I WILL LET THE OVERNIGHT SHIFT GET ANOTHER LOOK AT
THIS POTENTIAL TO SEE IF EITHER A WIND ADVISORY OR HIGH WIND
WARNING WILL BE NEEDED FOR THIS PERIOD.
KJB
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...
300 PM...STRONG LOW PRESSURE OVER WISCONSIN WILL CONTINUE TO
DEEPEN THURSDAY NIGHT AS IT LIFTS NORTH TO LAKE SUPERIOR. THE
GRADIENT WILL REMAIN TIGHT THROUGH FRIDAY AFTERNOON WITH WESTERLY
WINDS 20-30 MPH WITH HIGHER GUSTS INTO THE 40 MPH RANGE. THERE
REMAINS A SMALL POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS LATE
THURSDAY NIGHT INTO EARLY FRIDAY MORNING MAINLY ACROSS THE NORTH
HALF/THIRD OF THE CWA. ANY AMOUNTS WILL BE LIGHT BUT WITH THE
CONTINUED STRONG WINDS...ANY FRESH SNOW WILL LIKELY CAUSE SOME
BLOWING/DRIFTING SNOW.
A WEAKER COLD FRONT/TROUGH WILL PASS ACROSS THE REGION FRIDAY
EVENING...BRINGING ANOTHER CHANCE OF LIGHT SNOW/SNOW SHOWERS AND
HAVE ADDED THIS TO THE FORECAST...BUT PRIOR TO ITS ARRIVAL...WEAK
WARM AIR ADVECTION WILL SPREAD ACROSS THE AREA WITH AT LEAST SOME
SUNSHINE THROUGH MIDDAY. HAVE BUMPED HIGH TEMPS UP A TAD INTO THE
MID/UPPER 30S ACROSS MUCH OF THE CWA BUT THIS IS STILL A FEW
DEGREES BELOW CURRENT GUIDANCE LEVELS AND MAY END UP BEING TOO
COOL.
COLDER AIR THEN SPREADS BACK ACROSS THE REGION THIS WEEKEND WITH
BELOW NORMAL/MUCH COLDER TEMPERATURES THROUGH THE MIDDLE OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 20S AND LOWS IN THE SINGLE DIGITS.
ECMWF/GFS HAVE BEEN SOMEWHAT CONSISTENT WITH A CLIPPER LIKE SYSTEM
MOVING ACROSS THE AREA MONDAY NIGHT WITH A TENTH OR TWO OF QPF.
THIS COULD EASILY FLUFF UP A FEW INCHES OF SNOW. HAVE MAINTAINED
GOING CHANCE POPS AS THE TREND HAS BEEN FOR IT TO SAG A LITTLE
FURTHER SOUTH AND PERHAPS AFFECT ONLY THE SOUTHERN PART OF THE CWA.
MODELS THAN DIFFER ON JUST HOW COLD THE NEXT PUNCH OF ARCTIC AIR
WILL BE WHEN IT ARRIVES WEDNESDAY/WEDNESDAY NIGHT. CMS
&&
.HYDROLOGY...
330 PM CST...THE STRONG LATE WINTER STORM SYSTEM IS EXPECTED TO
BRING CONDITIONS THAT WOULD BE CONDUCIVE TO THE POTENTIAL FOR
WIDESPREAD AREAL AND RIVER FLOODING TO NORTHERN ILLINOIS AND
NORTHWEST INDIANA.
PRECIPITATION IS EXPECTED TO BEGIN DURING THE EARLY MORNING HOURS
AND WILL INITIALLY BE A WINTRY MIX WITH LIGHT QPF AMOUNTS. THROUGH
THE MORNING AND INTO THE AFTERNOON...AS THE MAIN SFC LOW DEEPENS...
THE ASSOCIATED WARM FRONT WILL SURGE NORTH INTO WISCONSIN AND SET
UP A PERSISTENT FETCH OF WARM...MOIST AIR FROM A WIDE OPEN WESTERN
GLFMEX REGION. CURRENT INDICATORS SUGGEST THAT TEMPERATURES WILL
SURGE INTO THE UPPER 40S NEAR THE WISCONSIN BORDER TO THE MIDDLE
50S SOUTH OF THE ILLINOIS AND KANKAKEE RIVER VALLEYS. SFC
DEWPOINTS WILL ALSO SURGE INTO THE MIDDLE 40S TO AROUND 50F. THE
MODEL GUIDANCE SUGGESTS THAT PRECIPITABLE WATER VALUES WILL
APPROACH 1 INCH TOMORROW...WHICH IS AT LEAST 2 STANDARD DEVIATIONS
HIGHER THAN NORMAL FOR LATE FEBRUARY. THE HIGH PRECIPITABLE WATER
VALUES AND THE DYNAMIC SYSTEM ARE INDICATIVE THAT THE POTENTIAL
FOR A SIGNIFICANT AMOUNT OF LIQUID PRECIPITATION...WITH THE
CURRENT FORECAST CARRYING 0.75 TO 1.00 INCHES FOR THE PERIOD
FROM 09Z THURSDAY THROUGH 00Z FRIDAY. THE HEAVY RAIN WILL HAVE AN
IMPACT ON BOTH AREAL FLOOD AND RIVER FLOOD CONCERNS.
THE WARM...HIGH DEWPOINT AIR IS VERY EFFICIENT AT MELTING SNOW
AND...CURRENTLY...THERE IS 2 TO 4 INCHES OF LIQUID EQUIVALENT
TRAPPED IN THE SNOW PACK. THIS...COMBINED WITH AROUND 1 INCH OF
WIDESPREAD QPF...WOULD GIVE A WORST CASE SCENARIO OF 3 TO 5 INCHES
OF RAINFALL. HOWEVER...THERE ARE LIMITING AND COMPLICATING FACTORS
WHICH NEED TO PLAY OUT...WHICH WOULD ACT TO EITHER LIMIT THE FLOOD
POTENTIAL OR ENHANCE THE FLOOD POTENTIAL...ESPECIALLY FOR AREA
RIVERS. CURRENTLY...MOST AREA RIVERS AND STREAMS ARE EITHER TOTALLY
ICE COVERED OR ONLY HAVE VERY LIMITED AMOUNTS OF OPEN WATER...SINCE
THIS WINTER HAS SEEN AN UNUSUAL DEGREE OF EXTREME COLD. EVEN THE
ILLINOIS RIVER HAS MUCH MORE ICE COVERAGE THAN IS NORMALLY OBSERVED
IN A TYPICAL WINTER. HEAVY RAINFALL AND ICE COVERED RIVERS WILL
HAVE A TWO-FOLD IMPACT. THE CAPACITY OF ICE COVERED RIVERS IS MUCH
LOWER THAN OPEN RIVERS WITH THE RAIN COLLECTING ON TOP OF THE ICE AS
IT IT WERE A RIVER BED. SO...LESS RAINFALL WOULD BE NEEDED TO RAISE
WATER LEVELS ABOVE BANK FULL AND TO FLOOD STAGE. ALSO...THE RAINFALL
WILL INCREASE BASE FLOW AND INFILTRATION OF RAINFALL INTO THE
RIVERS...LEADING TO INCREASED STREAM FLOW RATES...INCREASING
HYDROSTATIC PRESSURE UNDER THE ICE...WHICH COULD THEN LEAD TO ICE
BREAKUP AND ICE JAM FLOODING. ANY ICE JAM FLOODING WOULD ONLY
COMPOUND ANY RIVER FLOODING CAUSED BY THE RAINFALL RUNNING OFF ON
TOP OF THE ICE. HOWEVER...SINCE THE FROST DEPTH IS AROUND 14 INCHES
ACROSS THE AREA...IT IS UNLIKELY THAT THE INFLUX OF WARM AIR AND
RAIN WILL HAVE A SIGNIFICANT IMPACT ON THE FROST DEPTH. SO...ANY
MELTING AND RAINFALL WILL LIKELY MOSTLY BECOME RUNOFF...RATHER THAN
BEING INCORPORATED INTO INCREASED BASE FLOW...SO THERE IS LESS OF A
THREAT FOR WIDESPREAD BREAKUP OF THE THICKER ICE. BUT THE
POSSIBILITY OF ICE BREAKUP AND ICE JAM FLOODING CAN NOT BE RULED OUT
FOR RIVERS WITH THINNER ICE COVERAGE. THERE IS ALSO SOME
UNCERTAINTY AS TO THE DEGREE OF SNOW MELT THAT CAN BE EXPECTED AND
THE ASSOCIATED IMPACT ON RIVER LEVELS. CURRENTLY...THE RIVER STAGE
MODELS HAVE BEEN RUN WITH THE PREMISE THAT THE SNOW PACK WILL NOT
COMPLETELY MELT...ESPECIALLY FOR THE NORTHERN PORTIONS OF THE CWA
WHICH HAVE A DEEPER SNOW PACK AND SHOULD BE COLDER FOR A LONGER
PERIOD OF TIME. THERE IS ALSO THE CONSIDERATION THAT THE SNOW PACK
WILL ABSORB SOME OF THE RAINFALL BEFORE IT IS CONVERTED INTO
RUNOFF. SO...ALL THINGS CONSIDERED...THERE WILL BE A SIGNIFICANT
CHANCE FOR RIVER FLOODING WITH MANY RIVERS REACHING OR EXCEEDING
BANK FULL...BUT MAJOR OR RECORD BREAKING RIVER STAGES IS NOT LIKELY.
FOR AREAL FLOODING...THE MAIN CONTRIBUTORS WILL BE THE HEAVY
RAINFALL AND MELTING SNOW. AGAIN...WITH THE FROST DEPTH OF 14
INCHES...IT IS UNLIKELY THAT THERE WILL BE SIGNIFICANT INFILTRATION
INTO THE GROUND AND SNOW MELT AND RAINFALL WILL COMBINE INTO RUNOFF.
HOWEVER...SIMILAR TO THE RIVER ISSUES...IT WILL BE TOUGH FOR ALL OF
THE SNOW PACK TO MELT AND SOME OF THE RAINFALL COULD BECOME TRAPPED
IN THE RESIDUAL SNOW PACK...WHICH WOULD IN TURN LOWER THE RUNOFF.
AT THIS POINT...FEEL THAT AREAL FLOODING WILL BE LIMITED TO FLOODING
OF LOW LYING AREAS...UNDERPASSES AND DITCHES ADJACENT TO ROADS.
ALSO...URBAN AND SUBURBAN AREAS COULD SEE WIDESPREAD AREAS OF
PONDING AND STANDING WATER DUE TO SNOW-CLOGGED STORM DRAINS.
FOR THE HEADLINES...WILL MAINTAIN THE GOING FLOOD WATCH AND MONITOR
CONDITIONS BEFORE EITHER GOING WITH A FLOOD WARNING OR AN URBAN AND
SMALL STREAM FLOOD ADVISORY. AS FOR AREA RIVERS...WILL WAIT UNTIL
THE NEXT MODEL RUNS FROM THE NCRFC BEFORE DECIDING ON HEADLINES FOR
AREA RIVERS. THE CURRENT RIVER FORECASTS DO CONSIDER THE
RAINFALL...BUT HAVE BEEN RUN WITH AN INITIAL CONDITION OF LIMITED
SNOW MELT. CHANGES IN THE INITIAL CONDITIONS FOR SNOW MELT AND QPF
WILL HAVE A SIGNIFICANT IMPACT ON THE RIVER STAGE FORECASTS.
KREIN
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* NO CONCERNS IN THE NEAR TERM.
* WINTRY MIX OF PCPN BEGINNING DURG THE PRE-DAWN HOURS...LIKELY
SN/FZRA...THOUGH THERE IS A CHANCE THAT SOME IP COULD MIX IN
BRIEFLY. AMOUNT OF ICE ACCUMULATION IS UNCERTAIN.
* TIMING OF CHANGEOVER FROM WINTRY MIX TO ALL RAIN. LIKELY BY ARND
12Z...BUT EXACT TIMING IS STILL UNCERTAIN.
* VIS MAY DROP TO IFR...OR POSSIBLY LIFR...IN BR/FG BY LATE
MORNING OR EARLY AFTERNOON.
* CHANCE OF ISOLD/EMBEDDED TSRA LATE MORNING THROUGH EARLY
AFTERNOON UNTIL FRONTAL PASSAGE.
* WINDS SHIFTING TO SSWLY-SWLY BY EARLY AFTERNOON...STRENGTHENING
AND BECMG GUSTY TO ARND 30KT IN THE LATE AFTERNOON. GUSTS COULD
POSSIBLY BE EVEN HIGHER LATE AFTERNOON/EARLY EVENING.
KREIN/BMD
//DISCUSSION...UPDATED 18Z...UPDATED 1845Z...
QUIET CONDITIONS THROUGH LATE TONIGHT. CLEAR SKIES WILL GIVE WAY
TO INCREASING MID AND HIGH CLOUD AS A COMPLEX WEATHER SYSTEM
DEVELOPS OVER THE CENTRAL PLAINS AND CLOUD COVER BEGINS TO RACE
OUT AHEAD OF THE DOUBLE BARRELED LOW PRESSURE SYSTEM. OF MAIN
CONCERN TO NRN IL/NWRN INDIANA WILL BE THE TRACK AND DEVELOPMENT
OF THE SOUTHERN OF THE 2 LOWS...WHICH IS EXPECTED TO INITIALLY
DEVELOP OVER THE SOUTH HIGH PLAINS AND AND RAPIDLY DEEPEN AS IT
TRACKS THROUGH THE MIDDLE MISSISSIPPI VALLEY TO EASTERN WISCONSIN
BY EARLY TOMORROW EVENING.
THIS SYSTEM WILL BRING A COMPLEX WEATHER SCENARIO TO THE TERMINALS
WHICH WILL BE HIGHLY DEPENDANT ON THE EXACT TRACK OF THE
SYSTEM...AS WELL AS THE IMPACT OF THE DENSE SNOW PACK OVER THE
REGION. BASED ON THE CURRENTLY EXPECTED TRACK...AN ASSOCIATED WARM
FRONT WOULD LIFT NWD THROUGH THE REGION. WITH WARMER AIR ALOFT
OVERRIDING THE COLDER AIR AND SNOW PACK AT THE SFC...PCPN SHOULD
START OUT AS EITHER ALL SNOW...OR A WINTRY MIX OF
FZRA/IP/SN/RA...WHICH WILL BE HIGHLY DEPENDANT ON THE DEPTH AND
DURATION OF A SUB-FREEZING LAYER AT THE SFC...WITH THE DENSE
SNOWPACK POSSIBLY HELPING TO KEEP SFC TEMPS AT ARND THE FREEZING
MARK. THERE ARE PLEANTY OF QUESTIONS MARKS WITH THIS
SYSTEM...AMONG THEM BEING THE DURATION OF THE FREEZING AND FROZEN
PCPN TYPES. THE SYSTEM IS EXPECTED TO BE VERY FAST-MOVING...BUT
VERY DYNAMIC. THE SPEED OF THE SYSTEM WILL HELP LIMIT THE DURATION
OF THE FREEZING/FROZEN PCPN AND SNOW OR ICE ACCUMULATIONS WOULD BE
MINOR...BUT THE DYNAMICS OF THE SYSTEM COULD HELP GENERATE SOME
ADDITIONAL DYNAMIC COOLING...WHICH WOULD DELAY A CHAGEOVER FROM
SNOW TO FREEZING PCPN AND ADD TO THE SNOW ACCUMULATION TOTALS.
BEST ESTIMATION AT THIS POINT WOULD BE THAT ICE AND SNOW
ACCUMULATIONS WILL BE RELATIVELY MINOR...BUT ENOUGH TO HAVE A
SIGNIFICANT IMPACT ON OPERATIONS EVEN IF THE DURATION IS LIMITED
TO 2-3 HOURS. HAVE RELATIVELY HIGH CONFIDENCE THAT PCPN WILL
CHANGE OVER TO ALL RAIN AS THE WARM FRONT LIFTS NORTH OF THE
TERMINALS. HOWEVER...THIS WILL BRING THE NEXT SIGNIFICANT CONCERN
OF HEAVY RAIN WITH EMBEDDED THUNDERSTORMS. BASED ON THE CURRENTLY
ANTICIPATED TRACK OF THE SYSTEM...WITH THE MAIN SFC LOW PASSING
THROUGH FAR NWRN IL WOULD PUT THE TERMINAL AREAS INTO A WARM
SECTOR OF THE SYSTEM...FOLLOWED BY THE PASSAGE OF A STRONG COLD
FRONT. THE STRONGEST FORCING AND INSTABILITY SHOULD FOCUS THE MOST
EXTENSIVE AND STRONGEST THUNDERSTORMS TO THE SOUTHEAST OF THE
TERMINALS...BUT FORCING AND INSTABILITY SHOULD BE SUFFICIENT FOR
ISOLATED/EMBEDDED THUNDER FROM LATE MORNING AND THROUGH THE
AFTERNOON HOURS. IN ADDITION TO THE RAIN AND THUNDER
CONCERNS...ALSO HAVE CONCERN FOR THE POTENTIAL FOR DENSE FOG WITH
THE ADVECTION OF WARM/MOIST AIR OVER THE SNOW PACK...WHICH WILL
ALSO HAVE INCREASING MOISTURE CONTENT AS THE SNOW ABSORBS THE
FALLING RAIN. WITH HIGH DEWPOINT WARM AIR OVERSPREADING THE
SNOW...THERE IS A CONCERN THAT DENSE FOG COULD DEVELOP BY LATE
MORNING/EARLY AFTERNOON...EVEN WITH STRENGTHENING SELY-SLY WINDS.
HAVE LIMITED THE LOWER EXTENT OF THE VISBY TO 3/4SM TO 1SM FOR
TOMORROW...BUT THERE IS THE POTENTIAL FOR PERIODS OF VISBY
DROPPING TO 1/4SM IN FOG UNTIL THE PASSAGE OF THE STRONG COLD
FRONT TOMORROW EVENING.
THE THIRD CONCERN WILL THEN BECOME WINDS. SELY WINDS WILL BEGIN
TO INCREASE THROUGH THE MORNING WITH THE APPROACH OF THE COLD
FRONT...WITH SELY-SLY WINDS INCREASING AND BECMG GUSTY APPROACHING
30KT LATE THIS AFTERNOON. WHILE IT WILL BE AFTER THE CURRENT TAF
PERIOD...WINDS WILL SHIFT THROUGH SWLY TO WLY FOLLOWING THE FROPA
AND INCREASE FURTHER...POSSIBLY GUSTING TO 40KT EARLY TOMORROW
EVENING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS THROUGH LATE TONIGHT.
* HIGH CONFIDENCE IN A PERIOD OF A WINTRY MIX OF PCPN DURG THE
EARLY MORNING HOURS...BUT LOWER CONFIDENCE IN TIMING AND
DURATION OF THE WINTRY MIX PCPN.
* HIGH CONFIDENCE THAT PCPN WILL CHANGE OVER TO ALL RAIN BY LATE
MORNING...BUT LOWER CONFIDENCE IN EXACT TIMING.
* MEDIUM CONFIDENCE IN WIND TRENDS.
* LOW TO MEDIUM CONFIDENCE IN VISBY TRENDS...ESPECIALLY RELATED TO
THE CHANCE FOR IFR/LIFR VIS IN FOG DEVELOPING LATE TOMORROW
MORNING INTO TOMORROW AFTERNOON.
KREIN/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...RAIN OR SNOW SHOWERS...WITH POSSIBLE MVFR
CONDITIONS. VERY STRONG SOUTHWEST WINDS OF 25 TO 35 MPH WITH GUSTS
UP TO 50 MPH
FRIDAY...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHANCE OF LIGHT SNOW.
TUESDAY...SLIGHT CHANCE OF LIGHT SNOW.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* WARM FRONT LIFTING ACROSS THE REGION LATE OVERNIGHT WITH CIGS
QUICKLY DROPPING TO IFR AND PRECIPITATION...POSSIBLY A WINTRY
MIX...OVERSPREADING THE AREA.
* SHIFTING WINDS THROUGH THE DAY...BECOMING GUSTY IN THE
AFTERNOON...AND VERY GUSTY IN THE EVENING.
BMD
//DISCUSSION...UPDATED 00Z...
HIGH PRESSURE LIES OVER THE OHIO VALLEY THIS EVENING WITH A RIDGE
EXTENDING INTO THE LOWER LAKES REGION PROVIDING LIGHT FLOW AND VFR
CONDITIONS LOCALLY. QUIET WEATHER WILL PERSIST THROUGH SOME OF THE
OVERNIGHT HOURS...BUT LOW PRESSURE WILL DEEPEN OVER THE SOUTHERN
PLAINS OVERNIGHT WITH A WARMFRONT LIFTING ACROSS THE REGION AND
CONDITIONS QUICKLY DETERIORATING. A LEAD WAVE IS EXPECTED TO PASS
OVER THE REGION EARLY THURSDAY MORNING WITH THE COLUMN QUICKLY
SATURATING AND CIGS FALLING FROM ROUGHLY 100-120 AT 06Z...TO AROUND
015 BY 11Z. TEMPERATURES WILL BE KEY OVERNIGHT TO DETERMINING PRECIP
TYPE...AND UNFORTUNATELY THERE REMAINS CONSIDERABLE UNCERTAINTY EVEN
THIS CLOSE TO THE ONSET OF PRECIP. HAVE LEANED CLOSELY TOWARDS RAP
GUIDANCE WITH NAM SUGGESTING WARMER TEMPS AND A QUICKER TRANSITION
TO RAIN. THE RAP DOES SUGGEST A SHORT WINDOW OF SNOW...BUT
TEMPERATURES ALOFT WARM QUICKLY ON THE NOSE OF A 50+KT LOW LEVEL JET
AND EXPECT FULL MELTING OF PRECIP AS IT FALLS TO THE SURFACE.
SURFACE TEMPS THEN WILL BE THE DETERMINING FACTOR IN THE PERSISTENCE
OF THE ICE THREAT...AND GUIDANCE SHOWS A LOT OF VARIABILITY IN HOW
QUICKLY SURFACE TEMPS WILL RISE ABOVE FREEZING. MEANWHILE...CIGS
WILL CONTINUE TO FALL WITH THE SURFACE LOW TRACK ACROSS NORTH
CENTRAL ILLINOIS BY LATE AFTERNOON. DEWPOINTS RISING IN THE MID TO
UPPER 30S BY EARLY TO MID AFTERNOON OVER THE SNOWPACK WILL ALSO POSE
A THREAT FOR DENSE FOG TO DEVELOP...THOUGH IT IS UNCERTAIN HOW LOW
VSBY WILL GO. ANOTHER 40-50KT LLJ WILL ADVECT VERY MODEST
INSTABILITY OVERHEAD RESULTING THE THE THREAT FOR EMBEDDED
THUNDERSTORMS MID TO LATE AFTERNOON. WINDS WILL TURN WESTERLY BEHIND
THE DEPARTING LOW...WITH GUSTS TO OR IN EXCESS OF 40 KTS AT TIMES
POSSIBLE LATE IN THE EVENING AND OVERNIGHT.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE IN CIG TRENDS AND MEDIUM CONFIDENCE IN TIMING.
* LOW-MEDIUM CONFIDENCE IN WIND DIRECTION/SPEED.
* HIGH CONFIDENCE IN PRECIPITATION OVERSPREADING THE AREA THOUGH
LOW TO MEDIUM CONFIDENCE IN PTYPE AND TIMING POTENTIAL
TRANSITION TO ALL RAIN.
* LOW CONFIDENCE IN HOW DENSE FOG WILL BECOME.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...CHC SNOW OVERNIGHT.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHC SNOW OVERNIGHT.
TUESDAY...VFR.
BMD
&&
.MARINE...
315 PM...LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS
TONIGHT AND DEEPEN AS IT MOVES TO SOUTHERN WISCONSIN THURSDAY
EVENING. THIS LOW WILL THEN CONTINUE TO DEEPEN AS IT REACHES LAKE
SUPERIOR FRIDAY MORNING. SOUTHERLY WINDS WILL TURN SOUTHEAST
TONIGHT AND GRADUALLY INCREASE OVERNIGHT THEN TURN A BIT MORE
EAST/SOUTHEAST THURSDAY AS SPEEDS INCREASE TO 30 KTS MIDDAY. AS
THE LOW APPROACHES...GALES WILL DEVELOP LATE THURSDAY AFTERNOON.
ONCE THE LOW REACHES WISCONSIN...WINDS WILL SHIFT TO THE SOUTHWEST
AND STEADILY INCREASE THROUGH HIGH END GALES AND POTENTIALLY INTO
STORM FORCE. HAVE UPGRADED THE GALE WATCH TO A GALE WARNING AS
CONFIDENCE IS HIGH BUT MAINTAINED THE STORM WATCH FOR NOW. THE LOW
WILL WEAKEN SOME AS IT REACHES JAMES BAY BUT THEN BECOME NEARLY
STATIONARY WHICH WILL ALLOW A FAIRLY STRONG WESTERLY GRADIENT TO
CONTINUE INTO THIS WEEKEND WITH GALES ENDING ACROSS THE NORTH
FRIDAY NIGHT OR SATURDAY MORNING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...3 AM THURSDAY
TO 6 PM THURSDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...3 AM THURSDAY
TO 6 PM THURSDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM THURSDAY TO
MIDNIGHT FRIDAY.
STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 PM
THURSDAY TO 4 PM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
317 AM CST TUE FEB 18 2014
.DISCUSSION...
248 PM CST
SHORT TERM...THROUGH TONIGHT...
WILL LEAVE THE WINTER STORM WARNING AS IS...WITH THE WESTERN
COUNTIES ENDING AT 6PM AND THE EASTERN COUNTIES ENDING AT 9PM CST.
TWO LOWS ARE OVER THE REGION. THE DEEPER ONE IS OVER SOUTHWEST MN
WHILE THE OTHER IS OVER SOUTHERN IL. BOTH LOWS HAVE DEEPENED IN
THE PAST HOUR. ALOFT...THERE IS AN UPPER LEVEL TROUGH FROM MN
THROUGH MO WITH A SLIGHT NEGATIVE TILT. THIS TROUGH IS PROVIDING THE
LIFT FOR THE SNOW. THE RAP HAS HAD A PRETTY GOOD IDEA OF THE FGEN
FORCING AND CAPE TODAY. THE FGEN IS FOCUSED JUST SOUTH OF THE CWA
AND HAVE IT PASSING FROM MCLEAN COUNTY INTO CENTRAL INDIANA LATE
THIS AFTERNOON AND THE CAPE REMAINS ON THE WARM SIDE OF THE FGEN
BAND. AS SUCH THINKING THUNDERSNOW WILL REMAIN CONFINED TO AREAS
SOUTH OF I-80 AND NORTHWEST INDIANA FOR THE NEXT COUPLE OF HOURS
BEFORE SHIFTING INTO INDIANA BY 3PM. BUT THINKING THUNDERSNOW IS NOT
AS LIKELY AS IT WAS EARLIER TODAY...AND WE ARE ON A DOWNWARD TREND.
AREAS SOUTH OF I-80 AND NW INDIANA...HAVE ALSO BEEN HARDEST HIT BY
SNOW THUS FAR WITH REPORTS AS HIGH AS 2.5 INCHES PER HOUR. THE AREA
OF SNOW RESPONSIBLE FOR THOSE INTENSE RATES HAS MOVED EAST. HOWEVER
ANOTHER BAND OF SNOW COINCIDING WITH THE FGEN BAND STRETCHES FROM
MCHENRY COUNTY THROUGH CHAMPAIGN COUNTY. IT JUST MOVED OVER THE
OFFICE HERE AND VSBY DROPPED TO LESS THAN 1/8 OF A MILE WITH HEAVY
SNOW. AS SUCH WILL KEEP HEAVY SNOW IN THE FORECAST AS THIS BAND
PROGRESSES EASTWARD. HAVE THE BAND PUSHING EAST OF THE CWA BY 5PM
CST.
THE BACK END OF THE SNOW STRETCHES FROM EASTERN MN TO PEORIA TO
DECATUR IL AND IS QUICKLY PUSHING EAST AS WELL. AS SUCH QUICKENED
THE END TIME OF SNOW IN THE GRIDS. LEFT TOTALS AS IS WITH GENERALLY
4 TO 8 INCHES ACROSS THE CWA. EXPECTING SLIGHTLY LOWER TOTALS ALONG
THE IL/WI STATE LINE AND THEN HIGHER TOTALS ACROSS THE SOUTHERN
CWA. WITH THIS BEING A WETTER TYPE SNOW...LEFT BLOWING SNOW OUT OF
THE FORECAST. WIND GUSTS PICK UP SOUTH OF I-80 BEHIND THE TROUGH
AXIS THIS EVENING. GUSTS UP TO 25 KT ARE EXPECTED...AND THEY
DIMINISH BY MORNING.
FOR TEMPS...THE PREVIOUS FORECAST WAS RIGHT ON SO DID NOT MAKE TOO
MANY CHANGES TO TODAYS TEMPS. FOR TONIGHT...WENT A BIT LOWER THAN
GUIDANCE GIVEN THE FRESH SNOW AND CLEARING SKIES. LOWS WILL BE IN
THE MID TEENS TO AROUND 20.
JEE
TUESDAY THROUGH WEDNESDAY...
SEMI-ZONAL FLOW OVERHEAD CONTINUES TO PUSH THE 500MB TROUGH AXIS TO
THE EAST OF THE REGION TUESDAY...WITH SFC RIDGING BUILDING INTO
NORTHERN IL/NORTHWEST IN. THE COMBINATION OF RIDGING...P-CLOUDY
SKIES...ALONG WITH MID-LVL TEMPS BEGINNING TO WARM...SHOULD ALLOW
SFC TEMPS TO WARM MID/UPR 30S TUE AFTN. A FEW POINTS ALONG THE FAR
SOUTHERN CWFA COULD TOUCH 40 DEGREES.
THEN WITH THE SEMI-ZONAL FLOW ALLOWING FOR A RELATIVELY FLUID
ENVIRONMENT...A WEAK TROUGH PIVOTS EAST FROM THE NORTHERN PLAINS TUE
AFTN/EVE...AND BRINGS THICKENING CLOUD COVER BACK TO THE FORECAST
AREA. LOCAL MODEL WAS INDICATING SOME SPRINKLES WITH THE WEAK WAVE
OVER THE NORTHERN PORTIONS OF THE FORECAST AREA TUE EVE...HOWEVER
FEEL TOO MUCH DRY AIR WILL NEED TO BE OVERCOME...SO WILL CONTINUE TO
RIDE WITH A DRY FORECAST THROUGH TUE NGT INTO WED AS FRONTAL
BOUNDARY SWEEPS EAST ACROSS THE CWFA. SFC RIDGING WILL DEPART
EAST...HOWEVER BROAD RIDGING ACROSS THE CENTRAL PLAINS WILL THEN
PROVIDE ANOTHER DRY INFLUENCE FOR THE AREA INTO WED. THIS FEATURE
WILL THEN SHIFT EAST TOWARDS THE OHIO VALLEY.
TEMPS ONLY COOL MARGINALLY TUE NGT ALOFT...SO NOT EXPECTING MUCH
COOLING AT THE SFC...THUS HAVE HELD ONTO TEMPS IN THE LOW/MID 20S
FOR OVERNIGHT LOWS. THEN FOR WED WITH ANOTHER DRY DAY AND P-CLOUDY
SKIES...TEMPS SHUD BE ABLE TO WARM BACK ABOVE FREEZING INTO THE
LOW/MID 30S.
WEAK MID-LVL RIDGE SLIDES OVERHEAD WED AFTN/EVE...WITH SFC RIDGING
KEEPING A SLIGHT INFLUENCE OVER THE CWFA THRU EARLY EVE. THIS SHUD
KEEP PRECIP OUT OF THE FORECAST AREA UNTIL LATE WED NGT/EARLY THUR.
CONFIDENCE...MEDIUM/HIGH.
THURSDAY THROUGH FRIDAY...
FOCUS REMAINS ON THE THURSDAY TIMEFRAME...ESPECIALLY WITH THE
SUBSTANTIAL WARM-UP THAT CONTINUES TO BE PROGGED BY NUMEROUS
FORECAST MODELS. WHILE SOME CORRECTIONS CONTINUE TO TAKE
PLACE...WITH RESPECT TO THE PLACEMENT/INTENSITY OF THE DEVELOPING
SHORTWAVE AND WARM AIR. 500MB TROUGH REMAINS MORE OF AN ELONGATED
SETUP...WITH THE VORT MAX OVER THE NORTHERN ROCKIES DESPITE THE
TROUGH STRETCHING SOUTH THROUGH THE FOOTHILLS OF COLORADO EARLY
THUR. GUIDANCE CONTINUES TO POINT TOWARDS A SFC WAVE DEVELOPING ON
THE LEE-SIDE OF THE ROCKIES NEAR SOUTHEAST COLORADO EARLY THUR. WITH
THE DOWNSTREAM RIDGING OVER THE SOUTHEAST CONUS...RETURN FLOW
MOISTURE WILL LIKELY STREAM NORTH AHEAD OF THIS DEVELOPING SYSTEM.
ENSEMBLES HAVE MAINTAINED A DECENT AGREEMENT WITH PWAT VALUES
NEARING 1" FOR AREAS ALONG AND SOUTH OF I-80 IN NORTHERN
IL/NORTHWEST IN THUR...WITH STRONG MFLUX CONVERGENCE AT 850MB. THIS
COUPLED WITH A VERY ROBUST LLVL JET...AND STRONG INSTABILITY...POINT
TOWARDS NOT ONLY THE POTENTIAL FOR MODERATE RAIN GIVEN THE SURGE IN
WARM AIR OVER THE FORECAST AREA...BUT ALSO THE POSSIBILITY FOR
STRONG THUNDERSTORMS. THE SPC HAS A PORTION OF THE FORECAST
AREA...OUTLOOKED FOR POSSIBLE STRONG THUNDERSTORMS. THIS REMAINS
MAINLY ALONG AND EAST OF A PONTIAC TO RENSSELAER LINE FOR THE MAIN
FOCUS AREA...HOWEVER GIVEN THE CONTINUED UNCERTAINTY ON
TIMING/INTENSITY/PLACEMENT OF THE SYSTEM THIS WILL LIKELY BE
ADJUSTED OVER TIME.
SHORTWAVE THEN SLIDES OVER THE FORECAST AREA THUR EVE...WITH A
FRONTAL BOUNDARY BRINGING AN END TO THE MILD AIRMASS AND RETURNING
P-TYPE BACK TO LGT SNOW BEFORE ENDING FRI MORNING FROM WEST TO EAST.
AFTER TEMPS REACHING INTO THE MID/UPR 40S THUR...FRI HIGHS WILL
RETURN TO MORE SEASONAL CONDS IN THE LOW/MID 30S.
CONFIDENCE...MEDIUM.
SATURDAY THROUGH EARLY NEXT WEEK...
THE UPCOMING WEEKEND THROUGH EARLY NEXT WEEK PATTERN IS PROGGED TO
RETURN TO WHAT HAS BEEN A COMMON PATTERN OF TROUGHING OVER THE GREAT
LAKES REGION...WITH HIGH AMPLITUDE RIDGING PUSHING INTO WESTERN
CANADA. TEMPS FOR THE WEEKEND WILL COOL BACK INTO THE 20S FOR HIGHS.
THEN GUIDANCE IS INDICATING A COUPLE WEAK MID-LVL WAVES TRAVERSING
THE REGION FOR THE SECOND HALF OF THE WEEKEND INTO EARLY NEXT WEEK.
CONFIDENCE...MEDIUM/HIGH.
&&
.HYDROLOGY...
LATEST MODEL GUIDANCE CONTINUES TO INDICATE ENHANCED CONCERN
REGARDING FLOODING POTENTIAL FOR THURSDAY...POSSIBLY LINGERING
INTO THE WEEKEND. MORE DETAIL METEOROLOGICAL DISCUSSION IS ABOVE.
NO CHANGES REALLY TO THE PREVIOUS HYDROLOGICAL DISCUSSION OTHER
THAN SLIGHTLY MORE SNOW AND SNOW WATER EQUIVALENT IS EXPECTED TO
BE IN PLACE AFTER TODAY`S SNOW SYSTEM. WILL FRESHEN UP THE ESF
AGAIN THIS MORNING BUT NOT PLANNING ANY BIG CHANGES.
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* MVFR CEILINGS LINGERING ACROSS BOTH MDW/ORD THRU 1130Z.
* PATCHY FOG THIS MORNING.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
SURFACE LOW/TROUGH CONTINUE TO EXIT THE REGION...WITH THE LOW
STRATUS LINGERING OVER PORTIONS OF NORTHERN ILLINOIS AND NORTHWEST
INDIANA. THIS STRATUS IS PROGRESSIVE WITH BOTH DISTANCE SPEED TOOL
AND SHORT TERM GUIDANCE BOTH TAKING THIS STRATUS EAST OF ALL THE
TERMINALS OVER THE NEXT 1-3 HOURS. WITH ITS DEPARTURE...DONT
ANTICIPATE MUCH IN TERMS OF CLOUD COVER FOR TUESDAY...OUTSIDE OF
HIGH LEVEL CIRRUS. AT THIS TIME...THE NEXT SYSTEM TO PUSH THROUGH
THE AREA SHOULD ONLY BRING ABOUT SOME MID LEVEL CLOUD COVER LATER
TUESDAY EVENING/OVERNIGHT...BUT WILL NEED TO KEEP AN EYE ON SOME
POSSIBLE LIGHT PRECIP. WESTERLY WINDS SHOULD RAPIDLY DROP OFF HERE
IN THE NEAR TERM WITH SURFACE RIDGING OCCURRING. AS THEY DECREASE
IN SPEED...WILL TURN MORE SOUTHERLY EARLY MONDAY MORNING...AND
THEN INCREASE IN SPEED THROUGH MID DAY.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH CONFIDENCE WITH CEILING TRENDS.
* HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION.
* MEDIUM CONFIDENCE WITH FOG.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...PREDOMINANTLY VFR.
WEDNESDAY NIGHT...RAIN OR FZRA DEVELOPING.
THURSDAY..RAIN/FOG/IFR LIKELY. CHANCE THUNDER. FZRA POSSIBLE IN
THE MORNING.
FRIDAY...VFR PROBABLE.
SATURDAY AND SUNDAY...SOME POTENTIAL FOR SNOW.
MDB
&&
.MARINE...
300 PM CST
HAVE EXTENDED THE GALE WARNING FOR THE CENTRAL PORTIONS OF LAKE
MICHIGAN INTO THIS EVENING AS A STRONG SOUTHEASTERLY PRESSURE
GRADIENT WILL REMAIN...BETWEEN STRONG HIGH PRESSURE SLOWLY MOVES
THROUGH THE NERN CONUS AND A DEEP TROUGH AND STRONG COLD FRONT
MOVE THROUGH THE UPPER MISSISSIPPI VALLEY AND INTO THE WESTERN
GREAT LAKES REGION. THE COLD FRONT WILL PUSH ACROSS THE LAKE
TONIGHT AND A WEAK RIDGE WILL QUICKLY FOLLOW THE FRONT...SETTING
UP A PERIOD OF RELATIVELY VARIABLE...BUT WEAKER WINDS OVER THE
LAKE. BY TUESDAY NIGHT...A CLIPPER TYPE SYSTEM WILL TRACK THROUGH
SRN CANADA...DRAGGING ANOTHER COLD FRONT ACROSS THE PLAINS. AS THE
FRONTAL TROUGH APPROACHES THE LAKES...SLY-SWLY WINDS WILL INCREASE
TO ARND 30KT...WITH OCCASIONAL GALE FORCE GUSTS POSSIBLE. THE NEXT
SIGNIFICANT WEATHER SYSTEM TO IMPACT THE LAKES IS EXPECTED TO
DEVELOP OVER THE PLAINS WEDNESDAY NIGHT WITH WEAKER LOW PRESSURE
DEVELOPING OVER THE DAKOTAS AND A STRONGER LOW DEVELOPING OVER THE
SOUTH HIGH PLAINS. THE SOUTHERN LOW WILL BE THE MAIN SYSTEM OF
CONCERN AS IT IS EXPECTED TO DEEPEN RAPIDLY AS IT TRACKS THROUGH
ERN WISCONSIN THURSDAY NIGHT...WHILE DRAGGING A STRONG COLD FRONT
ACROSS THE LAKE. SWLY WINDS MAY APPROACH GALE FORCE JUST AHEAD OF
THE COLD FRONT...AND WILL LIKELY EXCEED GALE FORCE WHILE SHIFTING
TO WLY FOLLOWING THE FROPA.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...NOON TUESDAY TO 10 PM TUESDAY.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1203 AM CST TUE FEB 18 2014
.DISCUSSION...
248 PM CST
SHORT TERM...THROUGH TONIGHT...
WILL LEAVE THE WINTER STORM WARNING AS IS...WITH THE WESTERN
COUNTIES ENDING AT 6PM AND THE EASTERN COUNTIES ENDING AT 9PM CST.
TWO LOWS ARE OVER THE REGION. THE DEEPER ONE IS OVER SOUTHWEST MN
WHILE THE OTHER IS OVER SOUTHERN IL. BOTH LOWS HAVE DEEPENED IN
THE PAST HOUR. ALOFT...THERE IS AN UPPER LEVEL TROUGH FROM MN
THROUGH MO WITH A SLIGHT NEGATIVE TILT. THIS TROUGH IS PROVIDING THE
LIFT FOR THE SNOW. THE RAP HAS HAD A PRETTY GOOD IDEA OF THE FGEN
FORCING AND CAPE TODAY. THE FGEN IS FOCUSED JUST SOUTH OF THE CWA
AND HAVE IT PASSING FROM MCLEAN COUNTY INTO CENTRAL INDIANA LATE
THIS AFTERNOON AND THE CAPE REMAINS ON THE WARM SIDE OF THE FGEN
BAND. AS SUCH THINKING THUNDERSNOW WILL REMAIN CONFINED TO AREAS
SOUTH OF I-80 AND NORTHWEST INDIANA FOR THE NEXT COUPLE OF HOURS
BEFORE SHIFTING INTO INDIANA BY 3PM. BUT THINKING THUNDERSNOW IS NOT
AS LIKELY AS IT WAS EARLIER TODAY...AND WE ARE ON A DOWNWARD TREND.
AREAS SOUTH OF I-80 AND NW INDIANA...HAVE ALSO BEEN HARDEST HIT BY
SNOW THUS FAR WITH REPORTS AS HIGH AS 2.5 INCHES PER HOUR. THE AREA
OF SNOW RESPONSIBLE FOR THOSE INTENSE RATES HAS MOVED EAST. HOWEVER
ANOTHER BAND OF SNOW COINCIDING WITH THE FGEN BAND STRETCHES FROM
MCHENRY COUNTY THROUGH CHAMPAIGN COUNTY. IT JUST MOVED OVER THE
OFFICE HERE AND VSBY DROPPED TO LESS THAN 1/8 OF A MILE WITH HEAVY
SNOW. AS SUCH WILL KEEP HEAVY SNOW IN THE FORECAST AS THIS BAND
PROGRESSES EASTWARD. HAVE THE BAND PUSHING EAST OF THE CWA BY 5PM
CST.
THE BACK END OF THE SNOW STRETCHES FROM EASTERN MN TO PEORIA TO
DECATUR IL AND IS QUICKLY PUSHING EAST AS WELL. AS SUCH QUICKENED
THE END TIME OF SNOW IN THE GRIDS. LEFT TOTALS AS IS WITH GENERALLY
4 TO 8 INCHES ACROSS THE CWA. EXPECTING SLIGHTLY LOWER TOTALS ALONG
THE IL/WI STATE LINE AND THEN HIGHER TOTALS ACROSS THE SOUTHERN
CWA. WITH THIS BEING A WETTER TYPE SNOW...LEFT BLOWING SNOW OUT OF
THE FORECAST. WIND GUSTS PICK UP SOUTH OF I-80 BEHIND THE TROUGH
AXIS THIS EVENING. GUSTS UP TO 25 KT ARE EXPECTED...AND THEY
DIMINISH BY MORNING.
FOR TEMPS...THE PREVIOUS FORECAST WAS RIGHT ON SO DID NOT MAKE TOO
MANY CHANGES TO TODAYS TEMPS. FOR TONIGHT...WENT A BIT LOWER THAN
GUIDANCE GIVEN THE FRESH SNOW AND CLEARING SKIES. LOWS WILL BE IN
THE MID TEENS TO AROUND 20.
JEE
TUESDAY THROUGH WEDNESDAY...
SEMI-ZONAL FLOW OVERHEAD CONTINUES TO PUSH THE 500MB TROUGH AXIS TO
THE EAST OF THE REGION TUESDAY...WITH SFC RIDGING BUILDING INTO
NORTHERN IL/NORTHWEST IN. THE COMBINATION OF RIDGING...P-CLOUDY
SKIES...ALONG WITH MID-LVL TEMPS BEGINNING TO WARM...SHOULD ALLOW
SFC TEMPS TO WARM MID/UPR 30S TUE AFTN. A FEW POINTS ALONG THE FAR
SOUTHERN CWFA COULD TOUCH 40 DEGREES.
THEN WITH THE SEMI-ZONAL FLOW ALLOWING FOR A RELATIVELY FLUID
ENVIRONMENT...A WEAK TROUGH PIVOTS EAST FROM THE NORTHERN PLAINS TUE
AFTN/EVE...AND BRINGS THICKENING CLOUD COVER BACK TO THE FORECAST
AREA. LOCAL MODEL WAS INDICATING SOME SPRINKLES WITH THE WEAK WAVE
OVER THE NORTHERN PORTIONS OF THE FORECAST AREA TUE EVE...HOWEVER
FEEL TOO MUCH DRY AIR WILL NEED TO BE OVERCOME...SO WILL CONTINUE TO
RIDE WITH A DRY FORECAST THROUGH TUE NGT INTO WED AS FRONTAL
BOUNDARY SWEEPS EAST ACROSS THE CWFA. SFC RIDGING WILL DEPART
EAST...HOWEVER BROAD RIDGING ACROSS THE CENTRAL PLAINS WILL THEN
PROVIDE ANOTHER DRY INFLUENCE FOR THE AREA INTO WED. THIS FEATURE
WILL THEN SHIFT EAST TOWARDS THE OHIO VALLEY.
TEMPS ONLY COOL MARGINALLY TUE NGT ALOFT...SO NOT EXPECTING MUCH
COOLING AT THE SFC...THUS HAVE HELD ONTO TEMPS IN THE LOW/MID 20S
FOR OVERNIGHT LOWS. THEN FOR WED WITH ANOTHER DRY DAY AND P-CLOUDY
SKIES...TEMPS SHUD BE ABLE TO WARM BACK ABOVE FREEZING INTO THE
LOW/MID 30S.
WEAK MID-LVL RIDGE SLIDES OVERHEAD WED AFTN/EVE...WITH SFC RIDGING
KEEPING A SLIGHT INFLUENCE OVER THE CWFA THRU EARLY EVE. THIS SHUD
KEEP PRECIP OUT OF THE FORECAST AREA UNTIL LATE WED NGT/EARLY THUR.
CONFIDENCE...MEDIUM/HIGH.
THURSDAY THROUGH FRIDAY...
FOCUS REMAINS ON THE THURSDAY TIMEFRAME...ESPECIALLY WITH THE
SUBSTANTIAL WARM-UP THAT CONTINUES TO BE PROGGED BY NUMEROUS
FORECAST MODELS. WHILE SOME CORRECTIONS CONTINUE TO TAKE
PLACE...WITH RESPECT TO THE PLACEMENT/INTENSITY OF THE DEVELOPING
SHORTWAVE AND WARM AIR. 500MB TROUGH REMAINS MORE OF AN ELONGATED
SETUP...WITH THE VORT MAX OVER THE NORTHERN ROCKIES DESPITE THE
TROUGH STRETCHING SOUTH THROUGH THE FOOTHILLS OF COLORADO EARLY
THUR. GUIDANCE CONTINUES TO POINT TOWARDS A SFC WAVE DEVELOPING ON
THE LEE-SIDE OF THE ROCKIES NEAR SOUTHEAST COLORADO EARLY THUR. WITH
THE DOWNSTREAM RIDGING OVER THE SOUTHEAST CONUS...RETURN FLOW
MOISTURE WILL LIKELY STREAM NORTH AHEAD OF THIS DEVELOPING SYSTEM.
ENSEMBLES HAVE MAINTAINED A DECENT AGREEMENT WITH PWAT VALUES
NEARING 1" FOR AREAS ALONG AND SOUTH OF I-80 IN NORTHERN
IL/NORTHWEST IN THUR...WITH STRONG MFLUX CONVERGENCE AT 850MB. THIS
COUPLED WITH A VERY ROBUST LLVL JET...AND STRONG INSTABILITY...POINT
TOWARDS NOT ONLY THE POTENTIAL FOR MODERATE RAIN GIVEN THE SURGE IN
WARM AIR OVER THE FORECAST AREA...BUT ALSO THE POSSIBILITY FOR
STRONG THUNDERSTORMS. THE SPC HAS A PORTION OF THE FORECAST
AREA...OUTLOOKED FOR POSSIBLE STRONG THUNDERSTORMS. THIS REMAINS
MAINLY ALONG AND EAST OF A PONTIAC TO RENSSELAER LINE FOR THE MAIN
FOCUS AREA...HOWEVER GIVEN THE CONTINUED UNCERTAINTY ON
TIMING/INTENSITY/PLACEMENT OF THE SYSTEM THIS WILL LIKELY BE
ADJUSTED OVER TIME.
SHORTWAVE THEN SLIDES OVER THE FORECAST AREA THUR EVE...WITH A
FRONTAL BOUNDARY BRINGING AN END TO THE MILD AIRMASS AND RETURNING
P-TYPE BACK TO LGT SNOW BEFORE ENDING FRI MORNING FROM WEST TO EAST.
AFTER TEMPS REACHING INTO THE MID/UPR 40S THUR...FRI HIGHS WILL
RETURN TO MORE SEASONAL CONDS IN THE LOW/MID 30S.
CONFIDENCE...MEDIUM.
SATURDAY THROUGH EARLY NEXT WEEK...
THE UPCOMING WEEKEND THROUGH EARLY NEXT WEEK PATTERN IS PROGGED TO
RETURN TO WHAT HAS BEEN A COMMON PATTERN OF TROUGHING OVER THE GREAT
LAKES REGION...WITH HIGH AMPLITUDE RIDGING PUSHING INTO WESTERN
CANADA. TEMPS FOR THE WEEKEND WILL COOL BACK INTO THE 20S FOR HIGHS.
THEN GUIDANCE IS INDICATING A COUPLE WEAK MID-LVL WAVES TRAVERSING
THE REGION FOR THE SECOND HALF OF THE WEEKEND INTO EARLY NEXT WEEK.
CONFIDENCE...MEDIUM/HIGH.
&&
.HYDROLOGY...
LATEST MODEL GUIDANCE CONTINUES TO INDICATE ENHANCED CONCERN
REGARDING FLOODING POTENTIAL FOR THURSDAY...POSSIBLY LINGERING
INTO THE WEEKEND. MORE DETAIL METEOROLOGICAL DISCUSSION IS ABOVE.
NO CHANGES REALLY TO THE PREVIOUS HYDROLOGICAL DISCUSSION OTHER
THAN SLIGHTLY MORE SNOW AND SNOW WATER EQUIVALENT IS EXPECTED TO
BE IN PLACE AFTER TODAY`S SNOW SYSTEM. WILL FRESHEN UP THE ESF
AGAIN THIS MORNING BUT NOT PLANNING ANY BIG CHANGES.
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MVFR CEILINGS LINGERING ACROSS BOTH MDW/ORD THRU 10Z.
* WESTERLY WINDS GUSTING TO AROUND 20KT EXPECTED TO DIMINISH WHILE
TURNING MORE SOUTHERLY OVERNIGHT THROUGH EARLY TUESDAY
MORNING...WITH BLOWING SNOW ENDING.
* PATCHY FOG THROUGH TUESDAY MORNING...WITH VIS IN THE 3-5SM
RANGE.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
SURFACE LOW/TROUGH CONTINUE TO EXIT THE REGION...WITH THE LOW
STRATUS LINGERING OVER PORTIONS OF NORTHERN ILLINOIS AND NORTHWEST
INDIANA. THIS STRATUS IS PROGRESSIVE WITH BOTH DISTANCE SPEED TOOL
AND SHORT TERM GUIDANCE BOTH TAKING THIS STRATUS EAST OF ALL THE
TERMINALS OVER THE NEXT 1-3 HOURS. WITH ITS DEPARTURE...DONT
ANTICIPATE MUCH IN TERMS OF CLOUD COVER FOR TUESDAY...OUTSIDE OF
HIGH LEVEL CIRRUS. AT THIS TIME...THE NEXT SYSTEM TO PUSH THROUGH
THE AREA SHOULD ONLY BRING ABOUT SOME MID LEVEL CLOUD COVER LATER
TUESDAY EVENING/OVERNIGHT...BUT WILL NEED TO KEEP AN EYE ON SOME
POSSIBLE LIGHT PRECIP. WESTERLY WINDS SHOULD RAPIDLY DROP OFF HERE
IN THE NEAR TERM WITH SURFACE RIDGING OCCURRING. AS THEY DECREASE
IN SPEED...WILL TURN MORE SOUTHERLY EARLY MONDAY MORNING...AND
THEN INCREASE IN SPEED THROUGH MID DAY.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE WITH CEILING TRENDS.
* HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION...AND BLOWING SNOW
TRENDS.
* MEDIUM CONFIDENCE WITH FOG AND VIS.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...PREDOMINANTLY VFR.
WEDNESDAY NIGHT...RAIN OR FZRA DEVELOPING.
THURSDAY..RAIN/FOG/IFR LIKELY. CHANCE THUNDER. FZRA POSSIBLE IN
THE MORNING.
FRIDAY...VFR PROBABLE.
SATURDAY AND SUNDAY...SOME POTENTIAL FOR SNOW.
MDB
&&
.MARINE...
300 PM CST
HAVE EXTENDED THE GALE WARNING FOR THE CENTRAL PORTIONS OF LAKE
MICHIGAN INTO THIS EVENING AS A STRONG SOUTHEASTERLY PRESSURE
GRADIENT WILL REMAIN...BETWEEN STRONG HIGH PRESSURE SLOWLY MOVES
THROUGH THE NERN CONUS AND A DEEP TROUGH AND STRONG COLD FRONT
MOVE THROUGH THE UPPER MISSISSIPPI VALLEY AND INTO THE WESTERN
GREAT LAKES REGION. THE COLD FRONT WILL PUSH ACROSS THE LAKE
TONIGHT AND A WEAK RIDGE WILL QUICKLY FOLLOW THE FRONT...SETTING
UP A PERIOD OF RELATIVELY VARIABLE...BUT WEAKER WINDS OVER THE
LAKE. BY TUESDAY NIGHT...A CLIPPER TYPE SYSTEM WILL TRACK THROUGH
SRN CANADA...DRAGGING ANOTHER COLD FRONT ACROSS THE PLAINS. AS THE
FRONTAL TROUGH APPROACHES THE LAKES...SLY-SWLY WINDS WILL INCREASE
TO ARND 30KT...WITH OCCASIONAL GALE FORCE GUSTS POSSIBLE. THE NEXT
SIGNIFICANT WEATHER SYSTEM TO IMPACT THE LAKES IS EXPECTED TO
DEVELOP OVER THE PLAINS WEDNESDAY NIGHT WITH WEAKER LOW PRESSURE
DEVELOPING OVER THE DAKOTAS AND A STRONGER LOW DEVELOPING OVER THE
SOUTH HIGH PLAINS. THE SOUTHERN LOW WILL BE THE MAIN SYSTEM OF
CONCERN AS IT IS EXPECTED TO DEEPEN RAPIDLY AS IT TRACKS THROUGH
ERN WISCONSIN THURSDAY NIGHT...WHILE DRAGGING A STRONG COLD FRONT
ACROSS THE LAKE. SWLY WINDS MAY APPROACH GALE FORCE JUST AHEAD OF
THE COLD FRONT...AND WILL LIKELY EXCEED GALE FORCE WHILE SHIFTING
TO WLY FOLLOWING THE FROPA.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1156 PM EST MON FEB 17 2014
.SYNOPSIS...
ISSUED AT 115 PM EST MON FEB 17 2014
A LOW PRESSURE SYSTEM OVER WEST CENTRAL INDIANA WILL MOVE RAPIDLY
NORTHEAST ACROSS NORTHERN INDIANA AND NORTHWEST OHIO THIS EVENING.
THIS SYSTEM WILL CAUSE SNOW ACROSS OUR AREA... HEAVY AT TIMES
THIS EVENING. SOME SLEET AND FREEZING RAIN WILL MIX WITH THE SNOW
ALONG AND SOUTH OF HIGHWAY 24 IN INDIANA AND OHIO. TOTAL SNOW
ACCUMULATIONS ARE FORECAST TO RANGE BETWEEN 2 AND 6 INCHES ACROSS
THE FORECAST AREA...HEAVIEST ACROSS NORTHWEST INDIANA AND SOUTHERN
MICHIGAN. BRISK WEST WINDS WILL DEVELOP IN THE WAKE OF THE LOW
OVERNIGHT CAUSING BLOWING AND DRIFTING SNOW. A HIGH PRESSURE RIDGE
WILL MOVE ACROSS THE AREA ON TUESDAY PROVIDING DRY CONDITIONS.
LOWS TONIGHT WILL BE AROUND 20... WITH HIGHS TUESDAY IN THE MIDDLE
TO UPPER 30S.
&&
.UPDATE...
ISSUED AT 934 PM EST MON FEB 17 2014
DEFORMATION ZONE SNOW CONTG TO DEVELOP OVER THE AREA THIS EVE.
THIS SHOULD END ACROSS OUR AREA FROM WEST-EAST OVERNIGHT AS
DEEPENING MID LEVEL LOW MOVES ENE INTO THE LWR GRTLKS. WSW WINDS
PICKING UP ACROSS SW PORTION OF CWA IN WAKE OF SFC LOW CURRENTLY
OVER NE PORTION OF THE AREA. THIS SHOULD RESULT IN CONSIDERABLE
BLOWING AND DRIFTING SNOW OVERNIGHT... THUS HAVE EXTENDED THE
WINTER WEATHER ADVISORY THROUGH THE EARLY MORNING HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 349 PM EST MON FEB 17 2014
SNOWFALL RATES 2-3.5 INCHES/HR IN XTRMLY HVY TSSN ENTERING WRN CWA.
CONTD VERY SIMILAR RAP/NAM/PREV BLENDED APPROACH UTILIZED WITH
MIDDAY UPDATE. GENERAL CONTD CONSENSUS OF SREF MEAN AND TIGHT PLUME
PACK IN ADDITION TO 12 UTC NAM COBB OUTPUT SUPPORTS LATEST EVENT
TOTALS IN PRIOR 1233 PM EST WSW UPDATE WITH HIEST GENRLY ALONG NORTH
OF TOLL ROAD. THANKFULLY XTRM RATES BRIEF AND WITH TRANSITION TO
LESS THAN OPTIMAL FLAKE SIZE OUTSIDE OF CONVECTIVE ELEMENTS SHOULD
KEEP MAJORITY OF ACCUMS TO LTE 6 INCHES. SOME CONCERN THOUGH FOR HIR
AMOUNTS WITH TROWAL LIFTING ACRS FAR NRN CWA THIS EVENING PRIOR TO
LIFTG FARTHER N OF CWA BYND 03 UTC...INDICATIONS THOUGH THAT IT WILL
LIE OUT E-W JUST NORTH OF CWA...BEFORE GRDL EWD LIFTOUT. LEADING
WARM CONVEYOR BELT INTENSE WITH XTRM MSTR TAP WITH 6-7 G/KG ON I295K
SFC SLIDES EWD THROUGH SRN IN THIS EVENING...PROVIDING XTRM
MFLUX/UVM ATOP NOSE OF RAMPING SWRLY 850-7H JET AXIS. JETLET OF 65
KTS AT 21 UTC POSITIONED ACRS SRN IN...STRENGTHENS TO 75 KTS MEAN
LYR FLOW INTO SRN OH BY 00 UTC. SPECIAL KILX MIDDAY SNDG YIELDS 320
J/KG MUCAPE/LIFTED FM 7H AND WHILE LATEST RAP TREND NOTED DOWNWARD
WRT MUCAPE WL CONT WITH PRIOR AREA ADDED AND HAVE NOW INCLUDED FAR
ERN AREAS AS WELL IN 22-02 UTC TIMEFRAME GIVEN APPROACH OF STOUT 6-7
C/KM MID TROPOSPHERIC LAPSE RATE PLUME AND SYSTEM DEEPENING. MID LVL
CIRC AND TO CLOSE OFF ACRS CHICAGOLAND SHORTLY AND TRACK EWD TO
WINDSOR ONT BY 09 UTC TUE...ALSO SUGGESTING HIEST AMOUNTS HERE/JUST
NORTH OF CWA...WHERE HIGHLY ELEVATED MAX UVM BEST COLLOCATED WITHIN
A SATURATED DGZ. RAPID CRASH OF CLOUD DEPTH IN WAKE OF SYSTEM IN
PERTURBED MOIST BLYR STILL SUGGESTIVE OF BRIEF LIGHT FZDZSN POTNL AT
BEFORE ENDING. HELD ONTO CLOUD COVER A BIT LONGER INTO TUE AWAITING
SHORTWAVE 925MB RIDGING THAT STILL HOLDS JUST WEST FM KGRB INTO NERN
IL AT 12 UTC TUE.
&&
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 349 PM EST MON FEB 17 2014
FOCUS CONTINUES ON WARMER TEMPERATURES/ADDITIONAL PRECIPITATION
THROUGH FRIDAY AND FLOODING/SEVERE WEATHER CONCERNS.
THE NEXT RIPPLE IN THE UPPER FLOW WILL AID IN THE DEVELOPMENT OF LOW
PRESSURE WHICH WILL TRACK ACROSS SOUTHERN CANADA WITH A TRAILING
COLD FRONT. THIS FRONT WILL SWEEP INTO THE REGION LATE TUES NGT INTO
WEDNESDAY BUT WILL BE STARVED OF MOISTURE AND DYNAMICS LEADING TO A
GENERALLY QUIET PASSAGE. ALTHOUGH COOLER AIR WILL ARRIVE BEHIND THE
FRONT...THIS WILL BE SHORT LIVED AND COMPARED TO THE AIR OF THE PAST
SEVERAL WEEKS WILL FEEL DOWNRIGHT NICE.
TEMPERATURES WILL CLIMB ABOVE FREEZING WEDNESDAY ALLOWING FOR THE
START OF THE MELTDOWN OF THE LARGE SNOWPACK ACROSS THE REGION.
DEWPOINTS WILL REMAIN IN THE 20S...KEEPING ANY FOG FORMATION AWAY
AND ALLOWING FOR A SLOW RELEASE AND NO SIGNIFICANT HYDRO ISSUES.
PIECE OF ENERGY ORIGINATING FROM GULF OF ALASKA UPPER LOW WILL DROP
INTO THE WESTERN STATES AND CARVE OUT A DEEPENING TROUGH WHICH WILL
ALLOW A SURGE OF EVEN WARMER AIR STARTING LATE WEDS NGT INTO THURS
GULF OF MEXICO OPENING WIDE TO SEND ABUNDANT MSTR TO THE REGION.
THIS WILL SET THE STAGE FOR PRECIP ARRIVING LATE WEDS NGT INTO
THURSDAY MORNING. LOW LEVEL THERMAL PROFILES SHOW ABOVE FREEZING
VALUES...HOWEVER REMAINING SNOWPACK MAY POSE A INITIAL CHALLENGE AND
THREAT OF BRIEF PERIOD OF FREEZING RAIN AT ONSET OF RAINFALL.
HOWEVER...BY MID THURSDAY MORNING TEMPS SHOULD BE ABOVE FREEZING AND
ANY ICING THREAT OVER. HAVE ADJUSTED GRIDS TO REFLECT THIS. IN
ADDITION...LAST FEW FRAMES OF NAM12 AND HINTS ON ECMWF/GFS INDICATE
NEGATIVE SHOWWALTER VALUES BEGIN TO NUDGE IN BY LATE MORNING IN
WESTERN AREAS AND ACROSS THE ENTIRE AREA THURS AFTERNOON. ECMWF IS
MOST AGGRESSIVE WITH MSTR RETURN AS SFC DEWPTS CLIMB INTO THE LOWER
50S IN SE HALF. WHILE SOME MODELS HINT THERE COULD BE A BREAK IN
PRECIP...HAVE DECIDED TO CONTINUE WITH CAT POPS...INTRODUCED THUNDER
WEST LATE AM AND INCREASED TO CHC THUNDER ALL AREAS THURS AFTN.
CONTINUED MENTION OF FOG WHICH WILL LIKELY BE DENSE AS DWPTS CLIMB
ABOVE 40S ACROSS THE ENTIRE AREA. BEST CHANCES FOR HEAVY RAINFALL
LOOK TO BE THROUGH THURS MORNING AND AGAIN LATE AFTN INTO EVENING AS
COLD FRONT ARRIVES. IN TERMS OF FLOODING THREAT...GREATEST RELEASE
WILL OCCUR INTO THURS EVE AND ONLY SLOW DOWN SOMEWHAT THURS NGT WITH
TEMPS CLIMBING BACK ABOVE FREEZING FRIDAY. IF ADVERTISED
DEWPOINTS DO ARRIVE...LIKELY WON`T BE MUCH OF A SNOWPACK LEFT WITH
FLOODING CONCERNS INCREASE SUBSTANTIALLY AND TEMPS IN THE 30S TO LOW
40S WILL ALLOW FOR CONTINUED MELTING. HWO AND ESF HAVE THIS HANDLED
WELL THUS FAR SO NO CHANGES PLANNED. TO COMPLICATE MATTERS
FURTHER...GIVEN THE AMOUNT OF MSTR...ELEVATED INSTABILITY AND STRONG
LL FLOW ON THE ORDER OF 60 KTS PLUS...THREAT FOR STG-SVR STORMS DOES
EXIST AND WILL NEED TO BE MONITORED. SPC PLACED IN/OH UNDER DAY 4
OUTLOOK FOR SEVERE ON MORNING ISSUANCE. WILL HOLD OFF FOR NOW ON
MENTION IN HWO.
SEVERAL CLIPPER SYSTEMS TO MOVE THROUGH OVER THE WEEKEND TO WRECK
HAVOC WITH TEMPS AS AFTERNOON HIGHS EVEN INTO SAT REMAIN NEAR OR
ABOVE FREEZING. MORE SIGNIFICANT BLAST OF COLD AIR WILL ARRIVE LATE
IN THE WEEKEND INTO NEXT WEEK AS 850 MB TEMPS DROP BACK TO -10 C OR
LOWER. CHANCE FOR PRECIP MAY ARRIVE WITH EACH CLIPPER SYSTEM BUT
KEEPING WITH GOING FORECAST WITH MINIMAL CHANCES FOR NOW AS
TIMING/TRACK ISSUES ABOUND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1156 PM EST MON FEB 17 2014
STRONG WINDS EXPECTED TO PERSIST EARLY THIS MORNING ON BACKSIDE OF
SFC LOW PRESSURE LIFTING THROUGH SOUTHEAST LOWER MICHIGAN. SOME
-SN/FZDZ AND IFR/LOW MVFR VISBY`S WILL LIKELY LINGER AT MAINLY FWA
ALONG TRAILING LOW LEVEL CONVERGENT AXIS THROUGH 10Z. SIGNIFICANT
DRYING/SUBSIDENCE WILL SUPPORT IMPROVING CONDITIONS LATER THIS
MORNING/AFTN WITH EVENTUAL BREAKUP OF LINGERING MVFR STRATUS DECK.
STRONG SOUTHWEST FLOW WILL DEVELOP LATER THIS AFTN/EVE AS ANOTHER
WEAKER SHORTWAVE IN PROGRESSIVE PACIFIC FLOW APPROACHES THE
REGION. VERY SHALLOW MIXING DEPTHS WILL LIMIT SFC WINDS WITH 55-60
KT LLJ WARRANTING A LLWS MENTION.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...WINTER WEATHER ADVISORY UNTIL 4 AM EST /3 AM CST/ TUESDAY FOR
INZ003>009-012>018-020-022>027-032>034.
MI...WINTER WEATHER ADVISORY UNTIL 4 AM EST TUESDAY FOR MIZ077>081.
OH...WINTER WEATHER ADVISORY UNTIL 4 AM EST TUESDAY FOR OHZ001-002-
004-005-015-016-024-025.
LM...NONE.
&&
$$
UPDATE...JT
SYNOPSIS...JT
SHORT TERM...MURPHY
LONG TERM...FISHER
AVIATION...STEINWEDEL
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
806 PM MST WED FEB 19 2014
.UPDATE...
ISSUED AT 806 PM MST WED FEB 19 2014
MADE SOME MINOR ADJUSTMENTS TO THE FORECAST. MAJORITY OF THE
FORECAST REMAINS UNCHANGED. WINDS ARE BEGINNING TO PICK UP WITH
LOCATIONS ACROSS NORTHEAST COLORADO NOW SUSTAINED AT 25 KTS AND
GUSTING TO 35-37 KTS. WINDS ARE EXPECTED TO CONTINUE INCREASING
THIS EVENING AS THE FRONT BLASTS THROUGH. SOME GUIDANCE CONTINUES
TO SUGGEST THAT WINDS WILL REALLY INCREASE OVER PORTIONS OF
NORTHWEST KANSAS LATE TONIGHT...POSSIBLY EXCEEDING HIGH WIND
WARNING CRITERIA. A SHORTER FUSED HIGH WIND WARNING MAY BE NEEDED
HOWEVER WITH CONFLICTING SIGNALS IN THE MODEL DATA...WAS NOT
CONFIDENT ENOUGH TO MAKE ANY CHANGES TO CURRENT HIGHLIGHTS.
WINDS FOR TOMORROW STILL LOOK ON TRACK. THERE ARE SOME INDICATIONS
THERE COULD BE SOME BLOWING DUST TOMORROW BUT WITH SNOW EXPECTED
TONIGHT AND MELTING TOMORROW...THINK THE GROUND WILL BE TOO WET IN
OUR AREA FOR BLOWING DUST PROBLEMS. THE MOST LIKELY LOCATIONS TO
SEE BLOWING DUST WOULD BE SOUTHWEST NEBRASKA WITH DUST MOVING IN
FROM THE NEBRASKA PANHANDLE. DID NOT PLACE BLOWING DUST INTO THE
GRIDS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 230 PM MST WED FEB 19 2014
LATEST RAP UPPER LEVEL ANALYSIS SHOWS TROUGH CENTERED OVER
SASKATCHEWAN CANADA WITH MEAN AXIS EXTENDING SOUTH OVER MONTANA
AND UTAH. AT THE SURFACE A COLD FRONT CURRENTLY EXTENDS FROM THE
DAKOTAS ACROSS CENTRAL WYOMING AND CENTRAL UTAH. OVER EASTERN
COLORADO A 994MB SURFACE LOW HAS DEVELOPED WITH TIGHT SOUTHERLY
GRADIENT IN PLACE OVER OUR CWA.
REGARDING WINTER WEATHER ADVISORY TONIGHT...
WINTER STORM SHOULD DEVELOPING AS TROUGH MOVES OUT OF NORTHERN
ROCKIES. UPPER LEVEL FORCING SHOULD INCREASE THIS EVENING WITH
COLD FRONT PUSHING SOUTH INTO NW PART OF THE CWA BY ABOUT
03Z...AND THEN ACROSS THE REMAINING CWA THROUGH 09Z. WHILE THERE
ISNT REALLY STRONG CAA BEHIND THIS FRONT...CHANGEOVER SHOULD BE
RELATIVELY QUICK FOR ALL BUT THE FAR SOUTHEAST AS SATURATION TO
WETBULB TEMP WOULD SUPPORT SNOW REACHING SURFACE. BEHIND THIS
FRONT THE COMBINATION OF VERY HIGH 3-6 HOUR PRESSURE RISES AND
STEEP LAPSE RATES WILL HELP MIX A VERY STRONG LLJ TO THE
SURFACE...WITH NEAR WARNING CRITERIA WINDS (60 MPH GUSTS)
POSSIBLE. GUIDANCE HAS GENERALLY TRENDED BACK A LITTLE ON WINDS
ALOFT COMPARED TO A DAY AGO...BUT CONFIDENCE IS IS STILL HIGH FOR
GUSTS AROUND 55 MPH (ISOLATED 60MPH). SHORT RANGE GUIDANCE
(RAP/HRRR) CONTINUES TO INDICATE A VERY INTENSE AND PROGRESSIVE
BAND OF PRECIP MOVING FROM THE NORTHWEST TO THE SOUTHEAST TONIGHT.
THIS GENERALLY MATCH RECENT TRENDS ON GUIDANCE (THOUGH THERE ARE
STILL MINOR DIFFERENCES ON QPF AMOUNTS AND POSITION).
TIMING/POSITION OF DEFORMATION PRECIP BAND WILL DETERMINE LOCATION
OF HIGHER SNOWFALL RATES AND TIMING OF POSSIBLE WHITEOUT
CONDITIONS. SNOW RATES WITH THIS BAND COULD BE QUITE INTENSE AS
MODEL CROSS SECTION CONTINUE TO INDICATE AN UNSTABLE LAYER
ASSOCIATED WITH THE BAND...WHICH COULD LEAD TO SNOWFALL RATES OF
AROUND 2" PER HOUR. DUE TO THE PROGRESSIVE NATURE OF THIS BAND THE
WORST VISIBILITIES ARE NOT EXPECTED TO MEET 3HR REQUIREMENT FOR
BLIZZARD WARNING...AND AMOUNTS WITH BAND SHOULD STILL BE AROUND 3"
MAX. NO CHANGE TO CURRENT WINTER WEATHER ADVISORY AT THIS
TIME...AND WILL ALLOW SUBSEQUENT SHIFT TO MONITOR FOR CHANGES IN
UPSTREAM TRENDS.
THURSDAY...LARGE SCALE SUBSIDENCE WILL SUPPORT RAPIDLY CLEARING
CONDITIONS FROM THE WEST TO THE EAST...WITH ALL PRECIP COMING TO
AN END AROUND SUNRISE. IT STILL LOOKS LIKE THERE WILL BE A BRIEF
REPRIEVE FROM THE STRONGEST WINDS THURSDAY MORNING BEFORE DAYTIME
MIXING BRINGS STRONGER WINDS BACK TO THE SURFACE. WINDS
ALOFT/MIXING HEIGHTS MIGHT SUPPORT NEAR WARNING CRITERIA BEING MET.
IT IS NOT A SLAM DUNK THAT WE WILL REACH WARNING CRITERIA
EVERYWHERE...AND CURRENT WIND ADVISORY THURSDAY COVERS WINDS TO 55
MPH (WHICH GENERALLY MATCHES CURRENT GUIDANCE). NO CHANGE TO WIND
ADVISORY WAS PLANNED WITH THIS UPDATE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 230 PM MST WED FEB 19 2014
THURSDAY NIGHT-SATURDAY...DRY CONDITIONS EXPECTED WITH VARYING
AMOUNTS OF CLOUDINESS...THICK AT TIMES. BREEZY TO PERHAPS WINDY
CONDITIONS FROM THE NORTHWEST LATE FRIDAY MORNING THROUGH THE
AFTERNOON. HIGHS FRIDAY UPPER 40S FAR NORTHWEST WITH 50S OVER THE
REMAINDER OF THE AREA. FOR SATURDAY COOLER BEHIND FRIDAYS FRONTAL
PASSAGE WITH UPPER 30S NORTHWEST TO MID/UPPER 40S FAR
SOUTH/SOUTHEAST. LOWS THROUGH THE PERIOD GENERALLY IN THE 20S.
SATURDAY NIGHT-WEDNESDAY NIGHT...FORECAST AREA UNDER NORTHWEST FLOW
THROUGH THE PERIOD. WILL HAVE A CHANCE OF SOME LIGHT PRECIPITATION
SATURDAY NIGHT AS A BATCH OF 850-500 MOISTURE MOVES ACROSS AREAS
GENERALLY ALONG AND NORTH OF THE INTERSTATE. SHOULD HAVE A LULL IN
ACTIVITY SUNDAY WITH A SMALL CHANCE OF PRECIP ACROSS THE NORTHEAST
SUNDAY NIGHT INTO MONDAY. COULD SEE ANOTHER ROUND OF LIGHT PRECIP
MONDAY NIGHT A BIT FURTHER WEST THEN PREVIOUS DAYS NEAR PROXIMITY
TO FAVORABLE PORTION OF UPPER JET. TUESDAY AND WEDNESDAY LOOK TO
BE DRY.
HIGH TEMPERATURES A BIT BELOW NORMAL SUNDAY THROUGH TUESDAY WITH
NEAR NORMAL READINGS WEDNESDAY. LOWS THROUGH THE PERIOD PRETTY
CLOSE TO NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 428 PM MST WED FEB 19 2014
THE TAF PERIOD WILL START OUT RELATIVELY QUIET WITH VFR CONDITIONS
BUT WILL DETERIORATE AS THE NEXT COLD FRONT MOVES THROUGH AND
SNOW...ALONG WITH STRONG...GUSTY NORTHWEST WINDS OCCUR BEHIND THE
FRONT. NAM AND RAP BUFKIT SOUNDINGS...ALONG WITH CONSIDERING WHAT
GUIDANCE HAD...PROVIDED THE BEST ASSESSMENT OF HOW CONDITIONS WILL
EVOLVE AS OF RIGHT NOW. AMENDMENTS WILL BE MADE AS THE EVENT
UNFOLDS.
FOR KGLD...THE COLD FRONT WILL MOVE THROUGH AROUND 06Z WITH WINDS
SHIFTING FROM THE SOUTHEAST TO THE NORTH...GUSTING TO 36 KTS WITH
LIGHT RAIN DEVELOPING SLIGHTLY AHEAD OF AND ALONG THE FRONT. ONCE
THE COLD FRONT MOVES THROUGH...CEILINGS WILL LOWER TO LIFR AND SNOW
WILL DEVELOP AROUND 08Z WITH NORTH WINDS GUSTING UP TO 45
KTS...WHICH WILL CREATE BLOWING SNOW DROPPING VISIBILITY DOWN TO
1SM. INCLUDED A TEMPO GROUP FOR HEAVY SNOWFALL AND BLOWING SNOW
DROPPING VISIBILITY DOWN TO 1/2SM. CONSIDERING THIS IS A FAIRLY
QUICK MOVING SYSTEM...HAVE SNOW ENDING AT 11Z WITH VFR CEILINGS.
BY LATE MORNING...NORTHWEST WINDS WILL PICK UP AGAIN...WITH GUSTS
AROUND 42 KTS. DID NOT INCLUDE BLOWING SNOW AT THIS TIME SINCE
TEMPERATURES MAY WARM ENOUGH TO MELT THE SNOW AND THE GROUND MAY
BE TOO SATURATED FROM THE SNOWFALL FOR BLOWING DUST.
FOR KMCK...THE COLD FRONT WILL MOVE THROUGH AROUND 07Z WITH WINDS
SHIFTING FROM THE SOUTHEAST TO THE NORTHWEST...GUSTING TO 40 KTS
WITH LIGHT RAIN DEVELOPING SLIGHTLY AHEAD OF AND ALONG THE FRONT.
CEILINGS WILL LOWER TO LIFR AND SNOW WILL DEVELOP AROUND 09Z WITH
NORTHWEST WINDS GUSTING TO 42 KTS...WHICH WILL CREATE BLOWING AND
DRIFTING SNOW DROPPING VISIBILITY DOWN TO 1SM. INCLUDED A TEMPO
GROUP FOR HEAVY SNOWFALL AND BLOWING SNOW DROPPING VISIBILITY DOWN
TO 1/2SM. SNOW SHOULD END AROUND 11Z WITH VFR CEILINGS RETURNING.
BY AFTERNOON...NORTHWEST WINDS WILL INCREASE GUSTING TO AROUND 41
KTS. ALSO DID NOT INCLUDE BLOWING SNOW AT THIS TIME SINCE
TEMPERATURES MAY BE WARM ENOUGH TO MELT THE SNOW AND THE GROUND
MAY BE TOO SATURATED FROM THE SNOWFALL FOR BLOWING DUST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL 6 AM MST /7 AM CST/ THURSDAY FOR
KSZ001-002-013-014-027-041.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ TO 5 PM MST /6 PM CST/
THURSDAY FOR KSZ001>004-013>016-027>029-041-042.
WINTER WEATHER ADVISORY FROM 1 AM TO 8 AM CST THURSDAY FOR
KSZ003-004-015-016-028-029-042.
CO...WINTER WEATHER ADVISORY UNTIL 6 AM MST THURSDAY FOR COZ090>092.
WIND ADVISORY FROM 9 AM TO 5 PM MST THURSDAY FOR COZ090>092.
NE...WINTER WEATHER ADVISORY UNTIL 6 AM MST /7 AM CST/ THURSDAY FOR
NEZ079>081.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ TO 5 PM MST /6 PM CST/
THURSDAY FOR NEZ079>081.
&&
$$
UPDATE...RRH
SHORT TERM...DR
LONG TERM...99
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS GOODLAND KS
444 PM MST WED FEB 19 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 230 PM MST WED FEB 19 2014
LATEST RAP UPPER LEVEL ANALYSIS SHOWS TROUGH CENTERED OVER
SASKATCHEWAN CANADA WITH MEAN AXIS EXTENDING SOUTH OVER MONTANA
AND UTAH. AT THE SURFACE A COLD FRONT CURRENTLY EXTENDS FROM THE
DAKOTAS ACROSS CENTRAL WYOMING AND CENTRAL UTAH. OVER EASTERN
COLORADO A 994MB SURFACE LOW HAS DEVELOPED WITH TIGHT SOUTHERLY
GRADIENT IN PLACE OVER OUR CWA.
REGARDING WINTER WEATHER ADVISORY TONIGHT...
WINTER STORM SHOULD DEVELOPING AS TROUGH MOVES OUT OF NORTHERN
ROCKIES. UPPER LEVEL FORCING SHOULD INCREASE THIS EVENING WITH
COLD FRONT PUSHING SOUTH INTO NW PART OF THE CWA BY ABOUT
03Z...AND THEN ACROSS THE REMAINING CWA THROUGH 09Z. WHILE THERE
ISNT REALLY STRONG CAA BEHIND THIS FRONT...CHANGEOVER SHOULD BE
RELATIVELY QUICK FOR ALL BUT THE FAR SOUTHEAST AS SATURATION TO
WETBULB TEMP WOULD SUPPORT SNOW REACHING SURFACE. BEHIND THIS
FRONT THE COMBINATION OF VERY HIGH 3-6 HOUR PRESSURE RISES AND
STEEP LAPSE RATES WILL HELP MIX A VERY STRONG LLJ TO THE
SURFACE...WITH NEAR WARNING CRITERIA WINDS (60 MPH GUSTS)
POSSIBLE. GUIDANCE HAS GENERALLY TRENDED BACK A LITTLE ON WINDS
ALOFT COMPARED TO A DAY AGO...BUT CONFIDENCE IS IS STILL HIGH FOR
GUSTS AROUND 55 MPH (ISOLATED 60MPH). SHORT RANGE GUIDANCE
(RAP/HRRR) CONTINUES TO INDICATE A VERY INTENSE AND PROGRESSIVE
BAND OF PRECIP MOVING FROM THE NORTHWEST TO THE SOUTHEAST TONIGHT.
THIS GENERALLY MATCH RECENT TRENDS ON GUIDANCE (THOUGH THERE ARE
STILL MINOR DIFFERENCES ON QPF AMOUNTS AND POSITION).
TIMING/POSITION OF DEFORMATION PRECIP BAND WILL DETERMINE LOCATION
OF HIGHER SNOWFALL RATES AND TIMING OF POSSIBLE WHITEOUT
CONDITIONS. SNOW RATES WITH THIS BAND COULD BE QUITE INTENSE AS
MODEL CROSS SECTION CONTINUE TO INDICATE AN UNSTABLE LAYER
ASSOCIATED WITH THE BAND...WHICH COULD LEAD TO SNOWFALL RATES OF
AROUND 2" PER HOUR. DUE TO THE PROGRESSIVE NATURE OF THIS BAND THE
WORST VISIBILITIES ARE NOT EXPECTED TO MEET 3HR REQUIREMENT FOR
BLIZZARD WARNING...AND AMOUNTS WITH BAND SHOULD STILL BE AROUND 3"
MAX. NO CHANGE TO CURRENT WINTER WEATHER ADVISORY AT THIS
TIME...AND WILL ALLOW SUBSEQUENT SHIFT TO MONITOR FOR CHANGES IN
UPSTREAM TRENDS.
THURSDAY...LARGE SCALE SUBSIDENCE WILL SUPPORT RAPIDLY CLEARING
CONDITIONS FROM THE WEST TO THE EAST...WITH ALL PRECIP COMING TO
AN END AROUND SUNRISE. IT STILL LOOKS LIKE THERE WILL BE A BRIEF
REPRIEVE FROM THE STRONGEST WINDS THURSDAY MORNING BEFORE DAYTIME
MIXING BRINGS STRONGER WINDS BACK TO THE SURFACE. WINDS
ALOFT/MIXING HEIGHTS MIGHT SUPPORT NEAR WARNING CRITERIA BEING MET.
IT IS NOT A SLAM DUNK THAT WE WILL REACH WARNING CRITERIA
EVERYWHERE...AND CURRENT WIND ADVISORY THURSDAY COVERS WINDS TO 55
MPH (WHICH GENERALLY MATCHES CURRENT GUIDANCE). NO CHANGE TO WIND
ADVISORY WAS PLANNED WITH THIS UPDATE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 230 PM MST WED FEB 19 2014
THURSDAY NIGHT-SATURDAY...DRY CONDITIONS EXPECTED WITH VARYING
AMOUNTS OF CLOUDINESS...THICK AT TIMES. BREEZY TO PERHAPS WINDY
CONDITIONS FROM THE NORTHWEST LATE FRIDAY MORNING THROUGH THE
AFTERNOON. HIGHS FRIDAY UPPER 40S FAR NORTHWEST WITH 50S OVER THE
REMAINDER OF THE AREA. FOR SATURDAY COOLER BEHIND FRIDAYS FRONTAL
PASSAGE WITH UPPER 30S NORTHWEST TO MID/UPPER 40S FAR
SOUTH/SOUTHEAST. LOWS THROUGH THE PERIOD GENERALLY IN THE 20S.
SATURDAY NIGHT-WEDNESDAY NIGHT...FORECAST AREA UNDER NORTHWEST FLOW
THROUGH THE PERIOD. WILL HAVE A CHANCE OF SOME LIGHT PRECIPITATION
SATURDAY NIGHT AS A BATCH OF 850-500 MOISTURE MOVES ACROSS AREAS
GENERALLY ALONG AND NORTH OF THE INTERSTATE. SHOULD HAVE A LULL IN
ACTIVITY SUNDAY WITH A SMALL CHANCE OF PRECIP ACROSS THE NORTHEAST
SUNDAY NIGHT INTO MONDAY. COULD SEE ANOTHER ROUND OF LIGHT PRECIP
MONDAY NIGHT A BIT FURTHER WEST THEN PREVIOUS DAYS NEAR PROXIMITY
TO FAVORABLE PORTION OF UPPER JET. TUESDAY AND WEDNESDAY LOOK TO
BE DRY.
HIGH TEMPERATURES A BIT BELOW NORMAL SUNDAY THROUGH TUESDAY WITH
NEAR NORMAL READINGS WEDNESDAY. LOWS THROUGH THE PERIOD PRETTY
CLOSE TO NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 428 PM MST WED FEB 19 2014
THE TAF PERIOD WILL START OUT RELATIVELY QUIET WITH VFR CONDITIONS
BUT WILL DETERIORATE AS THE NEXT COLD FRONT MOVES THROUGH AND
SNOW...ALONG WITH STRONG...GUSTY NORTHWEST WINDS OCCUR BEHIND THE
FRONT. NAM AND RAP BUFKIT SOUNDINGS...ALONG WITH CONSIDERING WHAT
GUIDANCE HAD...PROVIDED THE BEST ASSESSMENT OF HOW CONDITIONS WILL
EVOLVE AS OF RIGHT NOW. AMMENDMENTS WILL BE MADE AS THE EVENT
UNFOLDS.
FOR KGLD...THE COLD FRONT WILL MOVE THROUGH AROUND 06Z WITH WINDS
SHIFTING FROM THE SOUTHEAST TO THE NORTH...GUSTING TO 36 KTS WITH
LIGHT RAIN DEVELOPING SLIGHTLY AHEAD OF AND ALONG THE FRONT. ONCE
THE COLD FRONT MOVES THROUGH...CEILINGS WILL LOWER TO LIFR AND SNOW
WILL DEVELOP AROUND 08Z WITH NORTH WINDS GUSTING UP TO 45
KTS...WHICH WILL CREATE BLOWING SNOW DROPPING VISIBILITY DOWN TO
1SM. INCLUDED A TEMPO GROUP FOR HEAVY SNOWFALL AND BLOWING SNOW
DROPPING VISIBILITY DOWN TO 1/2SM. CONSIDERING THIS IS A FAIRLY
QUICK MOVING SYSTEM...HAVE SNOW ENDING AT 11Z WITH VFR CEILINGS.
BY LATE MORNING...NORTHWEST WINDS WILL PICK UP AGAIN...WITH GUSTS
AROUND 42 KTS. DID NOT INCLUDE BLOWING SNOW AT THIS TIME SINCE
TEMPERATURES MAY WARM ENOUGH TO MELT THE SNOW AND THE GROUND MAY
BE TOO SATURATED FROM THE SNOWFALL FOR BLOWING DUST.
FOR KMCK...THE COLD FRONT WILL MOVE THROUGH AROUND 07Z WITH WINDS
SHIFTING FROM THE SOUTHEAST TO THE NORTHWEST...GUSTING TO 40 KTS
WITH LIGHT RAIN DEVELOPING SLIGHTLY AHEAD OF AND ALONG THE FRONT.
CEILINGS WILL LOWER TO LIFR AND SNOW WILL DEVELOP AROUND 09Z WITH
NORTHWEST WINDS GUSTING TO 42 KTS...WHICH WILL CREATE BLOWING AND
DRIFTING SNOW DROPPING VISIBILITY DOWN TO 1SM. INCLUDED A TEMPO
GROUP FOR HEAVY SNOWFALL AND BLOWING SNOW DROPPING VISIBILITY DOWN
TO 1/2SM. SNOW SHOULD END AROUND 11Z WITH VFR CEILINGS RETURNING.
BY AFTERNOON...NORTHWEST WINDS WILL INCREASE GUSTING TO AROUND 41
KTS. ALSO DID NOT INCLUDE BLOWING SNOW AT THIS TIME SINCE
TEMPERATURES MAY BE WARM ENOUGH TO MELT THE SNOW AND THE GROUND
MAY BE TOO SATURATED FROM THE SNOWFALL FOR BLOWING DUST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY FROM 8 PM MST /9 PM CST/ THIS EVENING TO
6 AM MST /7 AM CST/ THURSDAY FOR KSZ001-002-013-014-027-041.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ TO 5 PM MST /6 PM CST/
THURSDAY FOR KSZ001>004-013>016-027>029-041-042.
WINTER WEATHER ADVISORY FROM 1 AM TO 8 AM CST THURSDAY FOR
KSZ003-004-015-016-028-029-042.
CO...WINTER WEATHER ADVISORY FROM 8 PM THIS EVENING TO 6 AM MST
THURSDAY FOR COZ090>092.
WIND ADVISORY FROM 9 AM TO 5 PM MST THURSDAY FOR COZ090>092.
NE...WINTER WEATHER ADVISORY FROM 8 PM MST /9 PM CST/ THIS EVENING TO
6 AM MST /7 AM CST/ THURSDAY FOR NEZ079>081.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ TO 5 PM MST /6 PM CST/
THURSDAY FOR NEZ079>081.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS GOODLAND KS
224 PM MST TUE FEB 18 2014
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 145 PM MST TUE FEB 18 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS INDICATE SHORTWAVE TROUGH OVER
EASTERN NEBRASKA/KANSAS WITH SHORTWAVE RIDGE OVER THE GREAT BASIN
AND NORTHERN ROCKIES. A COLD FRONT (WHICH SHOWS UP BETTER WITH
VERTICAL THICKNESS FIELD) IS MOVING SOUTH TO THE KS/NE BORDER WITH A
PREFRONTAL SURFACE TROUGH AXIS NOW ACROSS CENTRAL KANSAS.
THIS AFTERNOON...STRONG PRESSURE GRADIENT HAS LED TO DEVELOPMENT OF
WIND GUSTS 45-60 MPH ACROSS THE NORTHERN HALF OF THE CWA...WITH
WINDS JUST STARTING TO COME UP ACROSS THE EAST AND SOUTH OVER THE
LAST HOUR. STRONGEST GUSTS WERE ASSOCIATED WITH INITIAL SURGE AS
SURFACE TROUGH SHIFTED SOUTH AND 3HR PRESSURE RISES BEHIND COLD
FRONT PEAKED AROUND 4MB. WINDS HAVE STABILIZED WITHIN ADVISORY
CRITERIA AFTER THIS INITIAL SURGE...SO DECISION WAS MADE TO HOLD
ONTO ADVISORY. RED FLAG CONDITIONS ARE BEING MET AT MOST OF WARNED
AREA...THOUGH INCREASING TD VALUES FROM THE NORTH ARE KEEPING RH
VALUES CLOSER TO 30 PERCENT ACROSS THE NORTHERN PART OF THE RFW. WE
MAY NOT MEET THE HIGH END THRESHOLD FOR RED FLAG CONDITIONS...
HOWEVER WITH THE MAGNITUDE OF WIND...I SEE NO REASON TO MAKE A CHANGE
TO GOING HEADLINES AT THIS POINT. RFW/NPW WILL CONTINUE THROUGH 01Z.
TONIGHT-WEDNESDAY...WINDS WILL QUICKLY DECREASE WITH LOSS OF DAYTIME
MIXING AND WEAKENING GRADIENT THIS EVENING. HIGH CLOUD COVER MOVING
IN FROM THE WEST LATER THIS EVENING MAY LIMIT RADIATIONAL COOLING
TONIGHT AND DIURNAL HEATING WEDNESDAY. LEE TROUGH ALSO REDEVELOPS
AFTER MIDNIGHT TONIGHT IN RESPONSE TO STRONG TROUGH MOVING OUT OF
THE PACIFIC NORTHWEST...WITH RESULTING SOUTHERLY FLOW SUPPORTING WAA
ACROSS THE WEST. I BUMPED LOW TEMPS UP TONIGHT AND HIGH TEMPS UP WED
FOR NOW...AND COULD SEE BOTH PERIODS BEING A LITTLE WARMER/COOLER
THAN ADVERTISED DEPENDING ON CLOUDS. OTHER IMMEDIATE CONCERN WILL BE
BREEZY-WINDY CONDITIONS WEDNESDAY AS SOUTHERLY GRADIENT INCREASE
AHEAD OF APPROACHING UPPER LEVEL SYSTEM. MODEL TEMPERATURE PROFILES
INDICATE MIXING HEIGHTS AROUND 750MB-800MB WHICH KEEPS WINDS JUST
UNDER (OR NEAR) ADVISORY CRITERIA...AND WITH CLOUD COVER POSSIBLY
LIMITING MIXING OVERALL...I DECIDED AGAINST ISSUANCE OF ANOTHER
ADVISORY WED AFTERNOON. UPPER LEVEL SYSTEM DOES APPROACH CENTRAL
ROCKIES WED AFTERNOON AND SURFACE TROUGH WILL SHIFT EAST ALLOWING
WINDS TO DECREASE LATER IN THE AFTERNOON. WHILE FORCING DOES BEGIN
TO INCREASE OVER THE ROCKIES...IT CURRENTLY LOOKS LIKE PRECIP
CHANCES SHOULD HOLD OFF UNTIL WED EVENING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 224 PM MST TUE FEB 18 2014
FORECAST CONCERNS WILL BE WINDS THROUGH FRIDAY AND PRECIPITATION
CHANCE/PHASE WEDNESDAY NIGHT. SATELLITE SHOWING A PROGRESSIVE AND
ACTIVE WAVE TRAIN FROM THE PACIFIC INTO THE ATLANTIC. NEXT SHORTWAVE
OF INTEREST IS ENTERING THE PACIFIC NORTHWEST. VERY DRY AIR MASS
ALOFT AT THIS TIME.
AT JET LEVEL...MODELS STARTED OUT FINE. AT MID LEVELS...LOOKS TO BE
NO SERIOUS INITIALIZATION PROBLEMS WITH THE MODELS MAYBE A LITTLE
TOO FAR SOUTH AND EAST. AT THIS TIME...THE ECMWF...CANADIAN...UKMET
AND GFS APPEAR TO BE DOING SLIGHTLY BETTER. ECMWF AND SREF WERE
DOING WELL INITIALLY WITH THE SURFACE WIND AND PRESSURE PATTERN.
THE CANADIAN...UKMET AND GFS WERE DOING THE BEST WITH THE LOW LEVEL
THERMAL FIELD.
WEDNESDAY NIGHT...AREA TRANSITIONS FROM WARM...DRY AND WINDY TO
COLD...WET AND WINDY. THERE ARE SOME DIFFERENCES IN THE JET AND
TROUGH POSITION. SOME MODELS HAVE THE LEFT FRONT QUADRANT WELL
SOUTH...AFFECTING THE SOUTHERN HALF OF THE AREA OR STILL TO THE WEST
OF THE AREA. BY THE MIDDLE OF THE NIGHT...THE JET AXIS HAS MOVED
ACROSS WITH THE MAIN AFFECT FROM THE LEFT FRONT QUADRANT ACROSS THE
SOUTHERN HALF OF THE AREA THROUGH THE EVENING. VERY STRONG
FRONTOGENITICAL FORCING MOVES ACROSS THE AREA FROM EARLY IN THE
EVENING TO LATE IN THE NIGHT. THETA-E LAPSE RATES NEAR ZERO OR
SLIGHTLY BELOW ZERO ARE NOT ONLY AT MID LEVELS FOR THE ENTIRE NIGHT
BUT FOR A BRIEF PERIOD ARE AT LOW LEVELS.
SO THE LIKELIHOOD OF PRECIPITATION IS PRETTY HIGH. THE QUESTION
BECOMES WHEN WILL THE PHASE CHANGE FROM RAIN TO SNOW AND HOW MUCH
SNOW WILL OCCUR AFTER THIS HAPPENS. MODEL SOUNDINGS AND WET BULB
PROGS WOULD INDICATE THE NORTHWEST HALF WILL TRANSITION FROM A
RAIN/SNOW MIX EARLY TO ALL SNOW BY 06Z. THE SOUTHEAST HALF WILL
HAVE RAIN UNTIL NEAR 05-06Z BEFORE RAPIDLY CHANGING TO SNOW.
PRECIPITABLE WATER NEARS A HALF INCH OVER THE EASTERN HALF TO TWO
THIRDS OF THE AREA. LIKE THE REPRESENTATION OF QPF THAT WPC HAS AND
USED AS A THE BUILDING BLOCK FOR THE QPF AND SNOWFALL. WPC SLR
GUIDANCE WOULD INDICATE A NEAR 13 TO 1 RATIO IS NEAR NORMAL AND THAT
SEEMS REASONABLE. SO CONSIDERING THE FORCING AND INSTABILITY...THE
SNOW COULD BE RATHER INTENSE AT TIMES DURING THE NIGHT.
SO WITH USING THE WPC QPF AND CUTTING OFF A LITTLE BIT DUE TO THE
EXPECTED PHASE TO BE RAIN...CAME UP WITH 1 TO 4 INCHES WITH THE
LOWEST IN THE FAR SOUTH AND THE MOST FROM YUMA COUNTY TO THE COUNTIES
ALONG THE KANSAS AND NEBRASKA BORDER.
ALL INDICATIONS ARE THAT VERY WINDY CONDITIONS WILL BE A CERTAINTY.
EXTREMELY TIGHT PRESSURE GRADIENT AND 3 HOUR PRESSURE RISES OF NEAR
10 MB WILL PRODUCE VERY WINDY CONDITIONS. AND THAT IS NOT EVEN
CONSIDERING THE POSSIBILITY OF MIXING DOWN EVEN STRONGER WINDS.
THOUGHT LONG AND HARD ABOUT HOW TO HANDLE THIS SCENARIO. WINDS
SHOULD BE IN THE HIGH WIND ADVISORY TO LOW HIGH WIND WARNING RANGE.
SO DESPITE THE AMOUNT OF SNOW EXPECTED...SIGNIFICANT BLOWING OF THAT
SNOW IS EXPECTED. DUE TO HOW FAST THE SNOW MOVES ACROSS THE AREA...3
HOURS OF BLIZZARD CONDITIONS ARE NOT EXPECTED TO OCCUR WHICH WOULD
MEAN A BLIZZARD WARNING. AFTER PLENTY OF DISCUSSION WE HAVE DECIDED
TO ISSUE A WINTER WEATHER ADVISORY AND EMPHASIZE THAT NEAR BLIZZARD
OR BLIZZARD CONDITIONS COULD OCCUR FOR A SHORT PERIOD OF TIME WITH
VISIBILITIES OF A HALF MILE TO A MILE EXPECTED FOR MOST OF THE
PERIOD. SNOW SHOULD BE DONE BY THE END OF THE NIGHT PLUS THE WINDS
SHOULD GO DOWN BY THAT TIME. SO THE WINTER WEATHER ADVISORY WILL BE
FOR THE WHOLE NIGHT FOR THE NORTHWEST HALF AND FOR THE SOUTHEAST HALF
FOR THE LAST HALF OF THE NIGHT ENDING AT 6 TO 7 AM LOCAL TIME.
THURSDAY/THURSDAY NIGHT...SOME DIFFERENCES IN THE SPEED OF INCOMING
NORTH TO SOUTH JET...BUT IT LOOKS TO BE WEST OF THE AREA THROUGH
THE DAY. THAT SEGMENT FLATTENS OUT WITH A WEST TO EAST JET AXIS AND
RIGHT REAR QUADRANT OVER THE NORTHERN HALF OF THE AREA BY THE END
OF THE NIGHT. AT THIS TIME ALL THE MOISTURE IS ALOFT SO THIS WILL
ONLY CAUSE CLOUDS.
THE BIG PROBLEM WILL BE THAT WINDS WILL COME UP AGAIN DURING THE
DAY BEHIND THE EXITING SHORTWAVE TROUGH. QUESTIONS WILL BE HOW
MUCH MIXING WILL OCCUR...ESPECIALLY IN THE NORTH...DUE TO SNOW ON THE
GROUND. LOOK TO STAY MIXED THROUGH THE NIGHT. DURING THE DAY THERE IS
GOOD UNIDIRECTIONAL FLOW WITH DECENT DOWNWARD MOTION. MODELS SHOW
GOOD LAPSE RATES TO AT LEAST 700 MB. SO IT WOULD APPEAR THINGS WILL
MIX WELL. MODEL SOUNDINGS WOULD INDICATE AT LEAST WIND ADVISORY...
POSSIBLY HIGH END...AND POSSIBLY REACHING HIGH WIND WARNING
CRITERIA. SO WILL KEEP WINDY TO VERY WINDY CONDITIONS AND THIS WILL
NEED TO BE ADDRESSED AFTER THE WINTER WEATHER ADVISORY IS DONE.
DEPENDING ON THE AMOUNT OF SNOW AND HOW MUCH IF ANY THE SNOW CRUSTS
OVER...THERE COULD BE SOME MORE BLOWING SNOW DESPITE NO PRECIPITATION
OCCURRING. SO DID PUT IN PATCHY BLOWING SNOW AT THIS TIME. WILL PUT
MAXES IN NEAR TO SLIGHTLY BELOW GUIDANCE.
FRIDAY...ABOVE JET MOVES SOUTH ACROSS THE AREA AT VARIOUS SPEEDS AND
WILL BE NEAR OR JUST SOUTH OF THE AREA BY THE END OF THE DAY. THIS
JUST LOOKS TO PRODUCE SOME CLOUDS. MODELS SHOWING WIND SPEEDS
INCREASING INTO THE WINDY CATEGORY AGAIN. LAPSE RATES LOOK TO STILL
STAY GOOD BUT THE FLOW IS NOT AS UNIDIRECTIONAL AND THE DOWNWARD
MOTION IS NOT AS GREAT. BUFKIT SOUNDINGS ARE INDICATING THE MIXING
DOWN OF A LEAST WIND ADVISORY CRITERIA WINDS AGAIN. WILL DEFINITELY
TRY AND HAVE WINDY WORDING IN THERE AT THIS TIME. TEMPERATURES
SHOULD BE WARMER BUT NOT SURE DEPENDING ON THE AMOUNT OF SNOW ON THE
GROUND.
FRIDAY NIGHT THROUGH TUESDAY...AT END OF THE SHORT TERM INTO THE
BEGINNING OF THIS PERIOD...THE PATTERN TRANSITIONS FROM A
PROGRESSIVE FLOW TO A HIGH AMPLITUDE RIDGE ALONG THE WEST COAST OF
NORTH AMERICA AND HUDSON BAY LOW BECOMING ESTABLISHED ONCE AGAIN BY
THE END OF THE PERIOD. PRECIPITATION IS VERY HARD TO PIN DOWN. WILL
HAVE VERY FAST WEST TO NORTHWEST FLOW WITH EMBEDDED SHORTWAVE TROUGHS
AND JET ENERGY. SIGNIFICANT MOISTURE WILL BE HARD TO COME BY IN THIS
SCENARIO. HOWEVER CANNOT RULE OUT SOME BRIEF AND SPOTTY PRECIPITATION
CHANCES. SO LEFT THE CRH_INIT POPS ALONE WHICH WERE NO HIGHER THAN
SLIGHT CHANCE WHICH SEEMS REASONABLE.
COLDER TEMPERATURES LOOK TO BE COMING BACK. BY LATE IN THE WEEKEND
A SHALLOW COLD AIR MASS WILL BE IN PLACE AS A SURFACE RIDGE BECOMES
ESTABLISHED OVER THE NORTH CENTRAL PORTION OF THE COUNTRY. SO
FOLLOWED OTHER OFFICES AND MADE SLIGHT ADJUSTMENTS DOWN IN
TEMPERATURES...ESPECIALLY THE MAXES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1018 AM MST TUE FEB 18 2014
WHILE VFR CONDITIONS ARE EXPECTED TO PREVAIL...THERE IS A
POSSIBILITY THAT GUSTY WINDS THIS AFTERNOON COULD RESULT IN
BLOWING DUST AND REDUCED VISIBILITIES TO MVFR/IFR AT BOTH
KGLD/KMCK. CONFIDENCE IS TOO LOW ON HOW THIS WOULD IMPACT EACH
TERMINAL...SO I LEFT MENTION OUT. WILL MONITOR FOR THESE
CONDITIONS AND ADJUST AS NEEDED. REGARDING WINDS...THERE SHOULD BE
AN INCREASING TREND OVER THE NEXT HOUR AS A SURFACE TROUGH MOVES
SOUTH AND PRESSURE GRADIENT INCREASES. GUSTS AROUND 40KT ARE STILL
EXPECTED THIS AFTERNOON. THERE SHOULD BE A DECREASE IN WINDS
OVERNIGHT BEFORE WINDS SHIFT FROM THE WEST TO THE SOUTH AND THEN
INCREASE ONCE AGAIN WEDNESDAY MORNING AS AN UPPER LEVEL SYSTEM
APPROACHES FROM THE NORTHWEST AND A SURFACE LOW DEVELOPS OVER
EASTERN COLORADO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 6 PM MST /7 PM CST/ THIS EVENING
FOR KSZ001>004-013>016-027>029-041-042.
WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ WEDNESDAY TO 6
AM MST /7 AM CST/ THURSDAY FOR KSZ001-002-013-027.
WIND ADVISORY UNTIL 6 PM MST /7 PM CST/ THIS EVENING FOR
KSZ001>004-013>016-027>029-041-042.
WINTER WEATHER ADVISORY FROM 10 PM MST /11 PM CST/ WEDNESDAY TO
6 AM MST /7 AM CST/ THURSDAY FOR KSZ003-004-014>016-028-029-
041-042.
CO...RED FLAG WARNING UNTIL 6 PM MST THIS EVENING FOR COZ252>254.
WINTER WEATHER ADVISORY FROM 7 PM WEDNESDAY TO 6 AM MST
THURSDAY FOR COZ090>092.
WIND ADVISORY UNTIL 6 PM MST THIS EVENING FOR COZ090>092.
NE...RED FLAG WARNING UNTIL 6 PM MST /7 PM CST/ THIS EVENING FOR
NEZ079>081.
WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ WEDNESDAY TO 6
AM MST /7 AM CST/ THURSDAY FOR NEZ079>081.
WIND ADVISORY UNTIL 6 PM MST /7 PM CST/ THIS EVENING FOR
NEZ079>081.
&&
$$
SHORT TERM...DJR
LONG TERM...BULLER
AVIATION...DJR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
145 PM MST TUE FEB 18 2014
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 145 PM MST TUE FEB 18 2014
LATEST WV IMAGERY AND RAP H5 ANALYSIS INDICATE SHORTWAVE TROUGH OVER
EASTERN NEBRASKA/KANSAS WITH SHORTWAVE RIDGE OVER THE GREAT BASIN
AND NORTHERN ROCKIES. A COLD FRONT (WHICH SHOWS UP BETTER WITH
VERTICAL THICKNESS FIELD) IS MOVING SOUTH TO THE KS/NE BORDER WITH A
PREFRONTAL SURFACE TROUGH AXIS NOW ACROSS CENTRAL KANSAS.
THIS AFTERNOON...STRONG PRESSURE GRADIENT HAS LED TO DEVELOPMENT OF
WIND GUSTS 45-60 MPH ACROSS THE NORTHERN HALF OF THE CWA...WITH
WINDS JUST STARTING TO COME UP ACROSS THE EAST AND SOUTH OVER THE
LAST HOUR. STRONGEST GUSTS WERE ASSOCIATED WITH INITIAL SURGE AS
SURFACE TROUGH SHIFTED SOUTH AND 3HR PRESSURE RISES BEHIND COLD
FRONT PEAKED AROUND 4MB. WINDS HAVE STABILIZED WITHIN ADVISORY
CRITERIA AFTER THIS INITIAL SURGE...SO DECISION WAS MADE TO HOLD
ONTO ADVISORY. RED FLAG CONDITIONS ARE BEING MET AT MOST OF WARNED
AREA...THOUGH INCREASING TD VALUES FROM THE NORTH ARE KEEPING RH
VALUES CLOSER TO 30 PERCENT ACROSS THE NORTHERN PART OF THE RFW. WE
MAY NOT MEET THE HIGH END THRESHOLD FOR RED FLAG CONDITIONS...HOWEVER
WITH THE MAGNITUDE OF WIND...I SEE NO REASON TO MAKE A CHANGE TO
GOING HEADLINES AT THIS POINT. RFW/NPW WILL CONTINUE THROUGH 01Z.
TONIGHT-WEDNESDAY...WINDS WILL QUICKLY DECREASE WITH LOSS OF DAYTIME
MIXING AND WEAKENING GRADIENT THIS EVENING. HIGH CLOUD COVER MOVING
IN FROM THE WEST LATER THIS EVENING MAY LIMIT RADIATIONAL COOLING
TONIGHT AND DIURNAL HEATING WEDNESDAY. LEE TROUGH ALSO REDEVELOPS
AFTER MIDNIGHT TONIGHT IN RESPONSE TO STRONG TROUGH MOVING OUT OF
THE PACIFIC NORTHWEST...WITH RESULTING SOUTHERLY FLOW SUPPORTING WAA
ACROSS THE WEST. I BUMPED LOW TEMPS UP TONIGHT AND HIGH TEMPS UP WED
FOR NOW...AND COULD SEE BOTH PERIODS BEING A LITTLE WARMER/COOLER
THAN ADVERTISED DEPENDING ON CLOUDS. OTHER IMMEDIATE CONCERN WILL BE
BREEZY-WINDY CONDITIONS WEDNESDAY AS SOUTHERLY GRADIENT INCREASE
AHEAD OF APPROACHING UPPER LEVEL SYSTEM. MODEL TEMPERATURE PROFILES
INDICATE MIXING HEIGHTS AROUND 750MB-800MB WHICH KEEPS WINDS JUST
UNDER (OR NEAR) ADVISORY CRITERIA...AND WITH CLOUD COVER POSSIBLY
LIMITING MIXING OVERALL...I DECIDED AGAINST ISSUANCE OF ANOTHER
ADVISORY WED AFTERNOON. UPPER LEVEL SYSTEM DOES APPROACH CENTRAL
ROCKIES WED AFTERNOON AND SURFACE TROUGH WILL SHIFT EAST ALLOWING
WINDS TO DECREASE LATER IN THE AFTERNOON. WHILE FORCING DOES BEGIN
TO INCREASE OVER THE ROCKIES...IT CURRENTLY LOOKS LIKE PRECIP
CHANCES SHOULD HOLD OFF UNTIL WED EVENING.
.LONG TERM...(FRIDAY THROUGH NEXT TUESDAY)
ISSUED AT 1231 AM MST TUE FEB 18 2014
A DEEP TROUGH WILL BE CARVED OUT ACROSS THE NORTHERN PLAINS AND
GREAT LAKES THIS PERIOD WITH A SERIES OF SHORTWAVE TROUGHS MOVING
THROUGH. BEST PRECIPITATION CHANCES WILL REMAIN NORTH OF THE LOCAL
AREA...ALTHOUGH CANNOT RULE OUT A SLIGHT CHANCE OF LIGHT
PRECIPITATION WITH THE SHORTWAVE EARLY NEXT WEEK WHICH TRACKS A
LITTLE FURTHER SOUTH. TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE
NORMAL EARLY IN THE PERIOD...BUT TEMPERATURES WILL FALL TO BELOW
NORMAL LATE IN THE WEEKEND AND ESPECIALLY EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1018 AM MST TUE FEB 18 2014
WHILE VFR CONDITIONS ARE EXPECTED TO PREVAIL...THERE IS A
POSSIBILITY THAT GUSTY WINDS THIS AFTERNOON COULD RESULT IN
BLOWING DUST AND REDUCED VISIBILITIES TO MVFR/IFR AT BOTH
KGLD/KMCK. CONFIDENCE IS TOO LOW ON HOW THIS WOULD IMPACT EACH
TERMINAL...SO I LEFT MENTION OUT. WILL MONITOR FOR THESE
CONDITIONS AND ADJUST AS NEEDED. REGARDING WINDS...THERE SHOULD BE
AN INCREASING TREND OVER THE NEXT HOUR AS A SURFACE TROUGH MOVES
SOUTH AND PRESSURE GRADIENT INCREASES. GUSTS AROUND 40KT ARE STILL
EXPECTED THIS AFTERNOON. THERE SHOULD BE A DECREASE IN WINDS
OVERNIGHT BEFORE WINDS SHIFT FROM THE WEST TO THE SOUTH AND THEN
INCREASE ONCE AGAIN WEDNESDAY MORNING AS AN UPPER LEVEL SYSTEM
APPROACHES FROM THE NORTHWEST AND A SURFACE LOW DEVELOPS OVER
EASTERN COLORADO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...RED FLAG WARNING UNTIL 6 PM MST /7 PM CST/ THIS EVENING FOR
KSZ001>004-013>016-027>029-041-042.
WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ WEDNESDAY TO 6
AM MST /7 AM CST/ THURSDAY FOR KSZ001-002-013-027.
WIND ADVISORY UNTIL 6 PM MST /7 PM CST/ THIS EVENING FOR
KSZ001>004-013>016-027>029-041-042.
WINTER WEATHER ADVISORY FROM 10 PM MST /11 PM CST/ WEDNESDAY TO
6 AM MST /7 AM CST/ THURSDAY FOR KSZ003-004-014>016-028-029-
041-042.
CO...RED FLAG WARNING UNTIL 6 PM MST THIS EVENING FOR COZ252>254.
WINTER WEATHER ADVISORY FROM 7 PM WEDNESDAY TO 6 AM MST THURSDAY
FOR COZ090>092.
WIND ADVISORY UNTIL 6 PM MST THIS EVENING FOR COZ090>092.
NE...RED FLAG WARNING UNTIL 6 PM MST /7 PM CST/ THIS EVENING FOR
NEZ079>081.
WINTER WEATHER ADVISORY FROM 7 PM MST /8 PM CST/ WEDNESDAY TO 6
AM MST /7 AM CST/ THURSDAY FOR NEZ079>081.
WIND ADVISORY UNTIL 6 PM MST /7 PM CST/ THIS EVENING FOR
NEZ079>081.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...DR
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1100 AM CST Tue Feb 18 2014
...UPDATE TO AVIATION...
.SYNOPSIS...
ISSUED AT 945 AM CST TUE FEB 18 2014
Water vapor imagery and 12Z upper air analysis indicate a prevailing
westerly flow aloft across the Western High Plains. Meanwhile, a
weak upper level shortwave trough is tracking eastward across the
Northern Plains. Near the surface, a lee side trough of low pressure
extends from extreme northwesterly Kansas down into southeastern
Colorado. Low level moisture has increased somewhat across central
and southwest Kansas with surface dewpoints up into the 20s(F).
&&
.UPDATE...
ISSUED AT 541 AM CST TUE FEB 18 2014
A Wind Advisory is in effect from 1 pm CST to 7 pm CST today. A
cold front will sweep down from Nebraska, and northwest winds
behind the front will increase to 25 to 35 mph with higher gusts.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 134 AM CST TUE FEB 18 2014
An upper level, sharply amplified trough over the Great Lakes region
will move northeast today and tonight. A zonal westerly flow from
the Rockies into to the plains will persist today. The main affect
will be streaming cirrus clouds across Kansas, and a slight down
slope warming affect. Nearer the surface, a low level jet of around
40 knots will set up across western Kansas towards 12z this morning,
and persist until it migrates to the east by 18z. This jet will mix
down partially, but probably not totally. Therefore, I think winds
will be from the southwest at 15 mph gusting to near 30 mph today,
and subside to westerly at 10 to 20 mph after 20z. A weak cold
front will drop south through the afternoon, and this will cause
winds to shift to the west as well. It will be unseasonably warm
with highs ranging from the mid 60s near Hays to the lower 70s
around Elkhart. Max temps may occur early today, prior to the cold
frontal passage. I loaded model Dew Points from the EC, GFS, NAM,
RUC and HRRR models, and the only model with lower dew points than
the others was the HRRR model. If the HRRR guidance Dew Points are
correct, we would have RH`s below 15% in our western half. But
since the other 4 models favored Dew Points in the upper teens and
20s, plus the fact that frequent gusts to 25 mph do not seem
likely, I decided not to issue a Red Flag Warning today. It should
be windier to the north of our forecast area, as well as drier, so
I can see the reason for fire headlines to my north.
The tonight period was not changed. The flow aloft will still be
from the west, and surface high pressure will be in control. Low
temperatures will be relatively mild for mid February, and should
settle into the 30F degree range in our western zones near Syracuse
and Johnson City, into the lower 30s in our north around Hays and
Ness City, and to the middle 30s in locations such as Medicine
Lodge, Pratt and Coldwater. Winds tonight should drop off fairly
mild from an east to northeast direction with that high building
down. By morning, winds should be from the south at 5 to 10 mph.
.LONG TERM...(Wednesday through Monday)
ISSUED AT 420 AM CST TUE FEB 18 2014
Busy extended period with a fairly significant cyclone to deal with
Wednesday/Thursday. The weighted blend solution (Friday onward) was
left as is.
Anyway, the main focus was on Wednesday and Thursday. A fairly intense
trof is located across the northeastern Pacific and into western Canada
as of this morning. This upper level feature will eventually be the
impetus to our sensible weather impacts midweek. The trof will be located
across the central Rockies Thursday morning. Significant dynamics are
associated with this as a 110-120 kt 250 hPa jet streak rounds the base
of the longwave trof and ejects across Kansas. An ageostrophic response
will lead to impressive surface cyclogenesis Wednesday evening through
Thursday evening across Kansas. Ahead of the sfc cyclone, low 40F dewpoints
will advect in across the warm sector. Depending on which model you
believe, some of the solutions are generating a few hundred J/kg of
MUCAPE. At this point, cannot rule out a rumble of thunder Wednesday
evening across central and south central Kansas. Moreover, The entire
lower tropospheric response is very impressive with a deep sfc to 850
hPa cyclone. Temperature advections are very impressive as well with
strong warm air advection Wednesday evening, followed by intense cold
air advection Thursday morning. This system has a lot of downslope southwesterly
momentum associated with it, so that will limit precipitation for the
southern 2/3rds of the forecast area of responsibility. Low level thermodynamic
profiles are rather warm, and this in combination with a delayed saturated
dendritic zone will limit overall snowfall amounts. Still, cannot rule
out an inch or so along the I70 corridor as the 700/850 hPa deformation
zone strengthens on the backside of the departing cyclone. Have made
spatiotemporal adjustments to pops with the highest probabilities across
the northern zones in association with WAA ahead of the cyclone and
the deformation zone is the most pronounced and developed behind the
cyclone. This area is also closer to the left exit region and the related
transverse circulation providing lift. Lastly, the whole kinematic profile
is very strong and a solid wind advisory is a no-brainer for Thursday.
Will defer to later shifts as we already have one issued in the short
term period. It will be very windy Thursday.
Beyond that, zonal to northwesterly flow aloft will continue thru the
weekend and into next week. This favors cooler temperatures, particularly
next week as colder 850 hPa temperatures advect in the wake of as passing
synoptic trof.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1100 AM CST TUE FEB 18 2014
VFR conditions will prevail at all TAF sites through early Wednesday
morning. As for winds, a weak cold front will push southward across
western Kansas this afternoon turning winds northerly 20 to 30kt
through early this evening. Surface high pressure will quickly
follow southeastward across western Kansas tonight resulting in
light and variable winds through daybreak Wednesday. Winds will
then become southerly 15 to 25kt mid to late morning Wednesday as
the surface high departs to the east.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 35 61 37 / 0 0 0 10
GCK 67 35 62 33 / 0 0 0 20
EHA 72 37 67 34 / 0 0 0 10
LBL 72 35 66 36 / 0 0 0 10
HYS 65 33 59 35 / 0 0 10 50
P28 67 35 60 46 / 0 0 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY from 1 PM this afternoon to 7 PM CST this evening
FOR KSZ030-031-043>046.
&&
$$
UPDATE...Burke
SYNOPSIS...JJohnson
SHORT TERM...Burke
LONG TERM...Sugden
AVIATION...JJohnson
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
947 AM CST Tue Feb 18 2014
...UPDATE TO SYNOPSIS...
.SYNOPSIS...
ISSUED AT 945 AM CST TUE FEB 18 2014
Water vapor imagery and 12Z upper air analysis indicate a prevailing
westerly flow aloft across the Western High Plains. Meanwhile, a
weak upper level shortwave trough is tracking eastward across the
Northern Plains. Near the surface, a lee side trough of low pressure
extends from extreme northwesterly Kansas down into southeastern
Colorado. Low level moisture has increased somewhat across central
and southwest Kansas with surface dewpoints up into the 20s(F).
&&
.UPDATE...
ISSUED AT 541 AM CST TUE FEB 18 2014
A Wind Advisory is in effect from 1 pm CST to 7 pm CST today. A
cold front will sweep down from Nebraska, and northwest winds
behind the front will increase to 25 to 35 mph with higher gusts.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 134 AM CST TUE FEB 18 2014
An upper level, sharply amplified trough over the Great Lakes region
will move northeast today and tonight. A zonal westerly flow from
the Rockies into to the plains will persist today. The main affect
will be streaming cirrus clouds across Kansas, and a slight down
slope warming affect. Nearer the surface, a low level jet of around
40 knots will set up across western Kansas towards 12z this morning,
and persist until it migrates to the east by 18z. This jet will mix
down partially, but probably not totally. Therefore, I think winds
will be from the southwest at 15 mph gusting to near 30 mph today,
and subside to westerly at 10 to 20 mph after 20z. A weak cold
front will drop south through the afternoon, and this will cause
winds to shift to the west as well. It will be unseasonably warm
with highs ranging from the mid 60s near Hays to the lower 70s
around Elkhart. Max temps may occur early today, prior to the cold
frontal passage. I loaded model Dew Points from the EC, GFS, NAM,
RUC and HRRR models, and the only model with lower dew points than
the others was the HRRR model. If the HRRR guidance Dew Points are
correct, we would have RH`s below 15% in our western half. But
since the other 4 models favored Dew Points in the upper teens and
20s, plus the fact that frequent gusts to 25 mph do not seem
likely, I decided not to issue a Red Flag Warning today. It should
be windier to the north of our forecast area, as well as drier, so
I can see the reason for fire headlines to my north.
The tonight period was not changed. The flow aloft will still be
from the west, and surface high pressure will be in control. Low
temperatures will be relatively mild for mid February, and should
settle into the 30F degree range in our western zones near Syracuse
and Johnson City, into the lower 30s in our north around Hays and
Ness City, and to the middle 30s in locations such as Medicine
Lodge, Pratt and Coldwater. Winds tonight should drop off fairly
mild from an east to northeast direction with that high building
down. By morning, winds should be from the south at 5 to 10 mph.
.LONG TERM...(Wednesday through Monday)
ISSUED AT 420 AM CST TUE FEB 18 2014
Busy extended period with a fairly significant cyclone to deal with
Wednesday/Thursday. The weighted blend solution (Friday onward) was
left as is.
Anyway, the main focus was on Wednesday and Thursday. A fairly intense
trof is located across the northeastern Pacific and into western Canada
as of this morning. This upper level feature will eventually be the
impetus to our sensible weather impacts midweek. The trof will be located
across the central Rockies Thursday morning. Significant dynamics are
associated with this as a 110-120 kt 250 hPa jet streak rounds the base
of the longwave trof and ejects across Kansas. An ageostrophic response
will lead to impressive surface cyclogenesis Wednesday evening through
Thursday evening across Kansas. Ahead of the sfc cyclone, low 40F dewpoints
will advect in across the warm sector. Depending on which model you
believe, some of the solutions are generating a few hundred J/kg of
MUCAPE. At this point, cannot rule out a rumble of thunder Wednesday
evening across central and south central Kansas. Moreover, The entire
lower tropospheric response is very impressive with a deep sfc to 850
hPa cyclone. Temperature advections are very impressive as well with
strong warm air advection Wednesday evening, followed by intense cold
air advection Thursday morning. This system has a lot of downslope southwesterly
momentum associated with it, so that will limit precipitation for the
southern 2/3rds of the forecast area of responsibility. Low level thermodynamic
profiles are rather warm, and this in combination with a delayed saturated
dendritic zone will limit overall snowfall amounts. Still, cannot rule
out an inch or so along the I70 corridor as the 700/850 hPa deformation
zone strengthens on the backside of the departing cyclone. Have made
spatiotemporal adjustments to pops with the highest probabilities across
the northern zones in association with WAA ahead of the cyclone and
the deformation zone is the most pronounced and developed behind the
cyclone. This area is also closer to the left exit region and the related
transverse circulation providing lift. Lastly, the whole kinematic profile
is very strong and a solid wind advisory is a no-brainer for Thursday.
Will defer to later shifts as we already have one issued in the short
term period. It will be very windy Thursday.
Beyond that, zonal to northwesterly flow aloft will continue thru the
weekend and into next week. This favors cooler temperatures, particularly
next week as colder 850 hPa temperatures advect in the wake of as passing
synoptic trof.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 500 AM CST TUE FEB 18 2014
Main focus is winds for this TAF issuance. Both sfc trof and cold front
will move across the region. This will result in southwesterly winds
veering northwesterly to northerly today. The strongest winds will be
for KHYS with magnitudes in the 25-35 kt range. Farther south, 20-30
kt winds expected for KGCK/KDDC. VFR conditions will prevail.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 35 61 37 / 0 0 0 10
GCK 67 35 62 33 / 0 0 0 20
EHA 72 37 67 34 / 0 0 0 10
LBL 72 35 66 36 / 0 0 0 10
HYS 65 33 59 35 / 0 0 10 50
P28 67 35 60 46 / 0 0 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY from 1 PM this afternoon to 7 PM CST this evening
FOR KSZ030-031-043>046.
&&
$$
UPDATE...Burke
SYNOPSIS...JJohnson
SHORT TERM...Burke
LONG TERM...Sugden
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
543 AM CST Tue Feb 18 2014
...Updated for the wind advisory...
.UPDATE...
ISSUED AT 541 AM CST TUE FEB 18 2014
A Wind Advisory is in effect from 1 pm CST to 7 pm CST today. A
cold front will sweep down from Nebraska, and northwest winds
behind the front will increase to 25 to 35 mph with higher gusts.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 134 AM CST TUE FEB 18 2014
An upper level, sharply amplified trough over the Great Lakes region
will move northeast today and tonight. A zonal westerly flow from
the Rockies into to the plains will persist today. The main affect
will be streaming cirrus clouds across Kansas, and a slight down
slope warming affect. Nearer the surface, a low level jet of around
40 knots will set up across western Kansas towards 12z this morning,
and persist until it migrates to the east by 18z. This jet will mix
down partially, but probably not totally. Therefore, I think winds
will be from the southwest at 15 mph gusting to near 30 mph today,
and subside to westerly at 10 to 20 mph after 20z. A weak cold
front will drop south through the afternoon, and this will cause
winds to shift to the west as well. It will be unseasonably warm
with highs ranging from the mid 60s near Hays to the lower 70s
around Elkhart. Max temps may occur early today, prior to the cold
frontal passage. I loaded model Dew Points from the EC, GFS, NAM,
RUC and HRRR models, and the only model with lower dew points than
the others was the HRRR model. If the HRRR guidance Dew Points are
correct, we would have RH`s below 15% in our western half. But
since the other 4 models favored Dew Points in the upper teens and
20s, plus the fact that frequent gusts to 25 mph do not seem
likely, I decided not to issue a Red Flag Warning today. It should
be windier to the north of our forecast area, as well as drier, so
I can see the reason for fire headlines to my north.
The tonight period was not changed. The flow aloft will still be
from the west, and surface high pressure will be in control. Low
temperatures will be relatively mild for mid February, and should
settle into the 30F degree range in our western zones near Syracuse
and Johnson City, into the lower 30s in our north around Hays and
Ness City, and to the middle 30s in locations such as Medicine
Lodge, Pratt and Coldwater. Winds tonight should drop off fairly
mild from an east to northeast direction with that high building
down. By morning, winds should be from the south at 5 to 10 mph.
.LONG TERM...(Wednesday through Monday)
ISSUED AT 420 AM CST TUE FEB 18 2014
Busy extended period with a fairly significant cyclone to deal with
Wednesday/Thursday. The weighted blend solution (Friday onward) was
left as is.
Anyway, the main focus was on Wednesday and Thursday. A fairly intense
trof is located across the northeastern Pacific and into western Canada
as of this morning. This upper level feature will eventually be the
impetus to our sensible weather impacts midweek. The trof will be located
across the central Rockies Thursday morning. Significant dynamics are
associated with this as a 110-120 kt 250 hPa jet streak rounds the base
of the longwave trof and ejects across Kansas. An ageostrophic response
will lead to impressive surface cyclogenesis Wednesday evening through
Thursday evening across Kansas. Ahead of the sfc cyclone, low 40F dewpoints
will advect in across the warm sector. Depending on which model you
believe, some of the solutions are generating a few hundred J/kg of
MUCAPE. At this point, cannot rule out a rumble of thunder Wednesday
evening across central and south central Kansas. Moreover, The entire
lower tropospheric response is very impressive with a deep sfc to 850
hPa cyclone. Temperature advections are very impressive as well with
strong warm air advection Wednesday evening, followed by intense cold
air advection Thursday morning. This system has a lot of downslope southwesterly
momentum associated with it, so that will limit precipitation for the
southern 2/3rds of the forecast area of responsibility. Low level thermodynamic
profiles are rather warm, and this in combination with a delayed saturated
dendritic zone will limit overall snowfall amounts. Still, cannot rule
out an inch or so along the I70 corridor as the 700/850 hPa deformation
zone strengthens on the backside of the departing cyclone. Have made
spatiotemporal adjustments to pops with the highest probabilities across
the northern zones in association with WAA ahead of the cyclone and
the deformation zone is the most pronounced and developed behind the
cyclone. This area is also closer to the left exit region and the related
transverse circulation providing lift. Lastly, the whole kinematic profile
is very strong and a solid wind advisory is a no-brainer for Thursday.
Will defer to later shifts as we already have one issued in the short
term period. It will be very windy Thursday.
Beyond that, zonal to northwesterly flow aloft will continue thru the
weekend and into next week. This favors cooler temperatures, particularly
next week as colder 850 hPa temperatures advect in the wake of as passing
synoptic trof.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 500 AM CST TUE FEB 18 2014
Main focus is winds for this TAF issuance. Both sfc trof and cold front
will move across the region. This will result in southwesterly winds
veering northwesterly to northerly today. The strongest winds will be
for KHYS with magnitudes in the 25-35 kt range. Farther south, 20-30
kt winds expected for KGCK/KDDC. VFR conditions will prevail.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 34 61 37 / 0 0 10 10
GCK 67 32 62 33 / 0 0 10 20
EHA 72 33 67 34 / 0 0 0 10
LBL 72 32 66 36 / 0 0 0 10
HYS 65 32 59 35 / 0 0 20 60
P28 67 36 60 46 / 0 0 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY from 1 PM this afternoon to 7 PM CST this evening
FOR KSZ030-031-043>046.
&&
$$
UPDATE...Burke
SHORT TERM...Burke
LONG TERM...Sugden
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
502 AM CST Tue Feb 18 2014
...Update to aviation for 12Z TAFs...
.SHORT TERM...(Today and tonight)
ISSUED AT 134 AM CST TUE FEB 18 2014
An upper level, sharply amplified trough over the Great Lakes region
will move northeast today and tonight. A zonal westerly flow from
the Rockies into to the plains will persist today. The main affect
will be streaming cirrus clouds across Kansas, and a slight down
slope warming affect. Nearer the surface, a low level jet of around
40 knots will set up across western Kansas towards 12z this morning,
and persist until it migrates to the east by 18z. This jet will mix
down partially, but probably not totally. Therefore, I think winds
will be from the southwest at 15 mph gusting to near 30 mph today,
and subside to westerly at 10 to 20 mph after 20z. A weak cold
front will drop south through the afternoon, and this will cause
winds to shift to the west as well. It will be unseasonably warm
with highs ranging from the mid 60s near Hays to the lower 70s
around Elkhart. Max temps may occur early today, prior to the cold
frontal passage. I loaded model Dew Points from the EC, GFS, NAM,
RUC and HRRR models, and the only model with lower dew points than
the others was the HRRR model. If the HRRR guidance Dew Points are
correct, we would have RH`s below 15% in our western half. But
since the other 4 models favored Dew Points in the upper teens and
20s, plus the fact that frequent gusts to 25 mph do not seem
likely, I decided not to issue a Red Flag Warning today. It should
be windier to the north of our forecast area, as well as drier, so
I can see the reason for fire headlines to my north.
The tonight period was not changed. The flow aloft will still be
from the west, and surface high pressure will be in control. Low
temperatures will be relatively mild for mid February, and should
settle into the 30F degree range in our western zones near Syracuse
and Johnson City, into the lower 30s in our north around Hays and
Ness City, and to the middle 30s in locations such as Medicine
Lodge, Pratt and Coldwater. Winds tonight should drop off fairly
mild from an east to northeast direction with that high building
down. By morning, winds should be from the south at 5 to 10 mph.
.LONG TERM...(Wednesday through Monday)
ISSUED AT 420 AM CST TUE FEB 18 2014
Busy extended period with a fairly significant cyclone to deal with
Wednesday/Thursday. The weighted blend solution (Friday onward) was
left as is.
Anyway, the main focus was on Wednesday and Thursday. A fairly intense
trof is located across the northeastern Pacific and into western Canada
as of this morning. This upper level feature will eventually be the
impetus to our sensible weather impacts midweek. The trof will be located
across the central Rockies Thursday morning. Significant dynamics are
associated with this as a 110-120 kt 250 hPa jet streak rounds the base
of the longwave trof and ejects across Kansas. An ageostrophic response
will lead to impressive surface cyclogenesis Wednesday evening through
Thursday evening across Kansas. Ahead of the sfc cyclone, low 40F dewpoints
will advect in across the warm sector. Depending on which model you
believe, some of the solutions are generating a few hundred J/kg of
MUCAPE. At this point, cannot rule out a rumble of thunder Wednesday
evening across central and south central Kansas. Moreover, The entire
lower tropospheric response is very impressive with a deep sfc to 850
hPa cyclone. Temperature advections are very impressive as well with
strong warm air advection Wednesday evening, followed by intense cold
air advection Thursday morning. This system has a lot of downslope southwesterly
momentum associated with it, so that will limit precipitation for the
southern 2/3rds of the forecast area of responsibility. Low level thermodynamic
profiles are rather warm, and this in combination with a delayed saturated
dendritic zone will limit overall snowfall amounts. Still, cannot rule
out an inch or so along the I70 corridor as the 700/850 hPa deformation
zone strengthens on the backside of the departing cyclone. Have made
spatiotemporal adjustments to pops with the highest probabilities across
the northern zones in association with WAA ahead of the cyclone and
the deformation zone is the most pronounced and developed behind the
cyclone. This area is also closer to the left exit region and the related
transverse circulation providing lift. Lastly, the whole kinematic profile
is very strong and a solid wind advisory is a no-brainer for Thursday.
Will defer to later shifts as we already have one issued in the short
term period. It will be very windy Thursday.
Beyond that, zonal to northwesterly flow aloft will continue thru the
weekend and into next week. This favors cooler temperatures, particularly
next week as colder 850 hPa temperatures advect in the wake of as passing
synoptic trof.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 500 AM CST TUE FEB 18 2014
Main focus is winds for this TAF issuance. Both sfc trof and cold front
will move across the region. This will result in southwesterly winds
veering northwesterly to northerly today. The strongest winds will be
for KHYS with magnitudes in the 25-35 kt range. Farther south, 20-30
kt winds expected for KGCK/KDDC. VFR conditions will prevail.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 34 61 37 / 0 0 10 10
GCK 67 32 62 33 / 0 0 10 20
EHA 72 33 67 34 / 0 0 0 10
LBL 72 32 66 36 / 0 0 0 10
HYS 65 32 59 35 / 0 0 20 60
P28 67 36 60 46 / 0 0 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY from 1 PM this afternoon to 7 PM CST this evening
FOR KSZ030-031-043>046.
&&
$$
SHORT TERM...Burke
LONG TERM...Sugden
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
420 AM CST Tue Feb 18 2014
...Update to long term...
.SHORT TERM...(Today and tonight)
ISSUED AT 134 AM CST TUE FEB 18 2014
An upper level, sharply amplified trough over the Great Lakes region
will move northeast today and tonight. A zonal westerly flow from
the Rockies into to the plains will persist today. The main affect
will be streaming cirrus clouds across Kansas, and a slight down
slope warming affect. Nearer the surface, a low level jet of around
40 knots will set up across western Kansas towards 12z this morning,
and persist until it migrates to the east by 18z. This jet will mix
down partially, but probably not totally. Therefore, I think winds
will be from the southwest at 15 mph gusting to near 30 mph today,
and subside to westerly at 10 to 20 mph after 20z. A weak cold
front will drop south through the afternoon, and this will cause
winds to shift to the west as well. It will be unseasonably warm
with highs ranging from the mid 60s near Hays to the lower 70s
around Elkhart. Max temps may occur early today, prior to the cold
frontal passage. I loaded model Dew Points from the EC, GFS, NAM,
RUC and HRRR models, and the only model with lower dew points than
the others was the HRRR model. If the HRRR guidance Dew Points are
correct, we would have RH`s below 15% in our western half. But
since the other 4 models favored Dew Points in the upper teens and
20s, plus the fact that frequent gusts to 25 mph do not seem
likely, I decided not to issue a Red Flag Warning today. It should
be windier to the north of our forecast area, as well as drier, so
I can see the reason for fire headlines to my north.
The tonight period was not changed. The flow aloft will still be
from the west, and surface high pressure will be in control. Low
temperatures will be relatively mild for mid February, and should
settle into the 30F degree range in our western zones near Syracuse
and Johnson City, into the lower 30s in our north around Hays and
Ness City, and to the middle 30s in locations such as Medicine
Lodge, Pratt and Coldwater. Winds tonight should drop off fairly
mild from an east to northeast direction with that high building
down. By morning, winds should be from the south at 5 to 10 mph.
.LONG TERM...(Wednesday through Monday)
ISSUED AT 420 AM CST TUE FEB 18 2014
Busy extended period with a fairly significant cyclone to deal with
Wednesday/Thursday. The weighted blend solution (Friday onward) was
left as is.
Anyway, the main focus was on Wednesday and Thursday. A fairly intense
trof is located across the northeastern Pacific and into western Canada
as of this morning. This upper level feature will eventually be the
impetus to our sensible weather impacts midweek. The trof will be located
across the central Rockies Thursday morning. Significant dynamics are
associated with this as a 110-120 kt 250 hPa jet streak rounds the base
of the longwave trof and ejects across Kansas. An ageostrophic response
will lead to impressive surface cyclogenesis Wednesday evening through
Thursday evening across Kansas. Ahead of the sfc cyclone, low 40F dewpoints
will advect in across the warm sector. Depending on which model you
believe, some of the solutions are generating a few hundred J/kg of
MUCAPE. At this point, cannot rule out a rumble of thunder Wednesday
evening across central and south central Kansas. Moreover, The entire
lower tropospheric response is very impressive with a deep sfc to 850
hPa cyclone. Temperature advections are very impressive as well with
strong warm air advection Wednesday evening, followed by intense cold
air advection Thursday morning. This system has a lot of downslope southwesterly
momentum associated with it, so that will limit precipitation for the
southern 2/3rds of the forecast area of responsibility. Low level thermodynamic
profiles are rather warm, and this in combination with a delayed saturated
dendritic zone will limit overall snowfall amounts. Still, cannot rule
out an inch or so along the I70 corridor as the 700/850 hPa deformation
zone strengthens on the backside of the departing cyclone. Have made
spatiotemporal adjustments to pops with the highest probabilities across
the northern zones in association with WAA ahead of the cyclone and
the deformation zone is the most pronounced and developed behind the
cyclone. This area is also closer to the left exit region and the related
transverse circulation providing lift. Lastly, the whole kinematic profile
is very strong and a solid wind advisory is a no-brainer for Thursday.
Will defer to later shifts as we already have one issued in the short
term period. It will be very windy Thursday.
Beyond that, zonal to northwesterly flow aloft will continue thru the
weekend and into next week. This favors cooler temperatures, particularly
next week as colder 850 hPa temperatures advect in the wake of as passing
synoptic trof.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
ISSUED AT 1141 PM CST MON FEB 17 2014
There will a low level jet setting up this morning, with winds
starting out from the southwest at 16g25kt. Plenty of high level
cirrus will be streaming by to the east, but will not lower any
cigs. Flight conditions will stay VFR through the 24 hour period.
Surface winds will shift to the west around 15 to 16Z, as a trough
crosses from west to east.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 34 61 37 / 0 0 10 10
GCK 67 32 62 33 / 0 0 10 20
EHA 72 33 67 34 / 0 0 0 10
LBL 72 32 66 36 / 0 0 0 10
HYS 65 32 59 35 / 0 0 20 60
P28 67 36 60 46 / 0 0 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY from 1 PM this afternoon to 7 PM CST this evening
FOR KSZ030-031-043>046.
&&
$$
SHORT TERM...Burke
LONG TERM...Sugden
AVIATION...Burke
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
142 AM CST Tue Feb 18 2014
...Updated for the short term discussion...
.SHORT TERM...(Today and tonight)
ISSUED AT 134 AM CST TUE FEB 18 2014
An upper level, sharply amplified trough over the Great Lakes region
will move northeast today and tonight. A zonal westerly flow from
the Rockies into to the plains will persist today. The main affect
will be streaming cirrus clouds across Kansas, and a slight down
slope warming affect. Nearer the surface, a low level jet of around
40 knots will set up across western Kansas towards 12z this morning,
and persist until it migrates to the east by 18z. This jet will mix
down partially, but probably not totally. Therefore, I think winds
will be from the southwest at 15 mph gusting to near 30 mph today,
and subside to westerly at 10 to 20 mph after 20z. A weak cold
front will drop south through the afternoon, and this will cause
winds to shift to the west as well. It will be unseasonably warm
with highs ranging from the mid 60s near Hays to the lower 70s
around Elkhart. Max temps may occur early today, prior to the cold
frontal passage. I loaded model Dew Points from the EC, GFS, NAM,
RUC and HRRR models, and the only model with lower dew points than
the others was the HRRR model. If the HRRR guidance Dew Points are
correct, we would have RH`s below 15% in our western half. But
since the other 4 models favored Dew Points in the upper teens and
20s, plus the fact that frequent gusts to 25 mph do not seem
likely, I decided not to issue a Red Flag Warning today. It should
be windier to the north of our forecast area, as well as drier, so
I can see the reason for fire headlines to my north.
The tonight period was not changed. The flow aloft will still be
from the west, and surface high pressure will be in control. Low
temperatures will be relatively mild for mid February, and should
settle into the 30F degree range in our western zones near Syracuse
and Johnson City, into the lower 30s in our north around Hays and
Ness City, and to the middle 30s in locations such as Medicine
Lodge, Pratt and Coldwater. Winds tonight should drop off fairly
mild from an east to northeast direction with that high building
down. By morning, winds should be from the south at 5 to 10 mph.
.LONG TERM...(Tuesday night through Monday)
ISSUED AT 202 PM CST MON FEB 17 2014
The extended period starts out dry with partly cloudy skies Tuesday
night into Wednesday with an increase in clouds Wednesday afternoon.
The main concern in the extended period will be Wednesday night into
Thursday as an upper level shortwave moves into the Rockies
Wednesday night and into the Plains on Thursday. This feature will
help push a cold front through western Kansas overnight Wednesday
shifting winds to more of a northerly direction with windy
conditions. A wind advisory may be needed overnight but do not have
enough confidence to place it in the grids at this time. A chance of
precipitation will also accompany this system with northern Kansas
having the best chance. Precipitation should start out as rain
Wednesday evening possibly changing over to snow as temperatures
fall to around and below zero. This system is still a few days out
so confidence in the exact timing and position of this system is
still low. Decreasing clouds are expected Thursday night into Friday
as the system moves to the east. The remainder of the forecast
period looks dry with partly cloudy skies. This is due to upper
level ridging across the western US with northwest flow aloft across
the Central High Plains. A weak shortwave is progged to move
southeast through this flow this weekend pushing a surface cold
front across the area on Saturday.
As for temperatures, highs Wednesday are expected to be around 60
degrees then decreasing to the 40s on Thursday behind the
aforementioned cold front. Lows Wednesday and Thursday morning are
anticipated to be in the lower to mid 30s. A brief warm up is
expected Friday as highs reach into the mid 50s. However, this will
be short lived as the next cold front moves through the area
Saturday with highs back in the 40s Saturday and Sunday. Lows Friday
through Sunday morning are forecasted to dip into the mid to upper
20s.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
ISSUED AT 1141 PM CST MON FEB 17 2014
There will a low level jet setting up this morning, with winds
starting out from the southwest at 16g25kt. Plenty of high level
cirrus will be streaming by to the east, but will not lower any
cigs. Flight conditions will stay VFR through the 24 hour period.
Surface winds will shift to the west around 15 to 16Z, as a trough
crosses from west to east.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 34 61 35 / 0 0 10 20
GCK 67 33 62 33 / 0 0 10 20
EHA 70 35 67 34 / 0 0 0 10
LBL 70 34 66 35 / 0 0 0 10
HYS 65 32 59 34 / 0 0 10 30
P28 67 36 60 41 / 0 0 10 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burke
LONG TERM...Hovorka_42
AVIATION...Burke
AREA FORECAST DISCUSSION
NWS GRAY ME
500 PM EST TUE FEB 18 2014
.SYNOPSIS...
LOW PRESSURE DEEPENS OFF THE NEW ENGLAND COAST AND MOVE OVER THE
GULF OF MAINE TONIGHT BEFORE MOVING INTO THE CANADIAN MARITIMES.
A COLD FRONT WILL SWING IN FROM THE WEST ON WEDNESDAY AND LOW
PRESSURE WILL DEVELOP ON THE FRONT AS IT PUSHES INTO THE GULF OF
MAINE WEDNESDAY EVENING. LOW PRESSURE WILL QUICKLY SHIFT EAST INTO
THE MARITIMES WEDNESDAY NIGHT. HIGH PRESSURE BUILD SIN FROM
THE WEST ON THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE REGION
THURSDAY NIGHT AND IS QUICKLY FOLLOWED BY A COLD FRONT FRIDAY.
HIGH PRESSURE BUILDS SOUTH OF NEW ENGLAND FRIDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
458 PM...BANDS OF HEAVY SNOW ARE RACING NORTH AND EAST ACROSS THE
FORECAST AREA. SNOWFALL RATES HAVE APPROACHED 3 INCHES PER HOUR
IN THE HEAVIEST BANDS. I`VE ADJUSTED AMOUNTS UP A BIT FOR THIS
UPDATE AND EXPANDED THE WARNING TO INCLUDE SEACOAST NEW HAMPSHIRE.
PREV DISC...
LOW PRES IS RAPIDLY DEVELOPING AS EXPECTED OVER SRN NEW ENGLAND
COAST ATTM. BASED ON RADAR AND SFC OBSERVATIONS...IT WOULD SEEM AS
IF LOW PRES WILL TRACK JUST N OF KPYM AND INTO THE GULF OF ME.
HEAVY SNFL HAS WORKED INTO SRN NH AND ADJACENT SWRN ME...WITH
RATES APPROACHING 1 TO 3 INCHES PER HOUR. SNFL TOTALS ARE ALREADY
PUSHING 4 TO 6 OR MORE ACROSS PARTS OF INTERIOR ROCKINGHAM COUNTY.
BASED ON MODEL PROGS AND REPORTS...FEEL THAT THIS IS THE AREA NOW
IN LINE FOR HIGHEST AMOUNTS IN THE CWFA. HAVE INCREASED QPF AND
SNFL FORECAST FOR THIS AREA. FOR THE REST OF THE AREA USED A BLEND
OF THE ECMWF...NAM12...RAP...AND NERFC QPF. THIS SHIFTED THE
HEAVIEST SN A LITTLE EWD FROM PREVIOUS FORECAST. SNFL AMOUNTS
STILL MATCHED HEADLINES WELL...SO THEY WILL REMAIN AS IS.
ELY WINDS HAVE ALSO WARMED THE IMMEDIATE COAST AOA FREEZING.
DESPITE THE WARM TEMPS...DEW POINT DEPRESSIONS WILL ALLOW WET BULB
COOLING TO KEEP PCPN MOSTLY SN. HOWEVER...IT MAY BE WETTER IN
NATURE AND CLING TO POWER LINES/TREES LEADING TO SCT POWER
OUTAGES. ELY WINDS ARE ALSO DOWNSLOPING ON THE N SIDE OF THE
WHITES...DRYING OUT THE COLUMN. SN WILL LIKELY STRUGGLE TO REACH
THE GROUND AT TIMES IN THE FAR N.
AS FOR SRN NH INTO SWRN ME...HEAVY SNFL REMAINS IN THE FORECAST
INTO THE EVENING. RAP CONTINUES TO SHOW FORECAST SOUNDINGS FROM
KCON TO NEAR KPWM APPROACHING A MAUL...MOIST ABSOLUTELY UNSTABLE
LAYER. MODEL GUIDANCE HAS AN AREA OF 6 TO 7 DEG/KM LAPSE RATES
ALOFT WORKING INTO THE REGION THRU THE EVENING. THIS KIND OF
INSTABILITY WOULD BE FAVORABLE FOR CONVECTION IN THE WARM
SEASON...LET ALONE FEBRUARY. THERE HAVE BEEN NO RECENT REPORTS OF
LIGHTNING...BUT WOULD NOT BE SURPRISED TO SEE A FEW IN THE NEXT
COUPLE OF HOURS. CONSIDERING THE SNFL OCCURRING ATTM IN SERN
NH...SEE NO REASON WHY THIS TREND WON/T THEN CONTINUE FOR THE NEXT
SEVERAL HOURS INTO SWRN ME. THIS IS ALL ONGOING AS MID LEVEL LOW
CENTER QUICKLY SPIN UP...MAXIMIZING DYNAMICS. AS THESE MATURE THIS
EVENING...SN WILL GRADUALLY TAPER TO MORE MODEST RATES. AS FORCING
SHIFTS EWD...SN WILL RAPIDLY END FROM S TO N AROUND MIDNIGHT.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS SOON AS TONIGHT`S STORM LIFTS INTO THE CANADIAN MARITIMES...
ANOTHER SHORT WAVE QUICKLY FOLLOWS ON ITS HEELS...FOLLOWING A
SIMILAR PATH. SURFACE LOW PRESSURE DEEPENS OVER THE GULF OF MAINE
WEDNESDAY AFTERNOON INTO THURSDAY MORNING. THIS STORM IS FORMING A
LITTLE TOO FAR OFFSHORE TO ACCOUNT FOR MORE THAN 1-3 INCHES AS IT
MOVES QUICKLY BY.
TEMPERATURES WILL BE IN THE MID 30S TO MID 40S WEDNESDAY THROUGH
FRIDAY AS WARM AIR ADVECTION IS REINFORCED EVERY 18 HRS OR SO.
THE TIMING OF THESE WAVES AS WELL AS NEAR ZONAL FLOW ALOFT WILL
KEEP ANY COLD AIR FROM TAKING HOLD FOR MOST OF THE WEEK.
HOWEVER...SOME COLDER AIR DOES MANAGE TO SNEAK IN BEHIND A COLD
FRONT ON FRIDAY. THIS WILL BE PRECEDED BY A WARM FRONT FRIDAY
MORNING. TEMPERATURES AT THE ONSET OF THIS PRECIPITATION EVENT
SUPPORTS A LARGE SWATH OF FREEZING RAIN AND POSSIBLY SOME SLEET
FRIDAY MORNING AS WARMER AIR OVERRIDES FREEZING TEMPERATURES
NEAR THE SURFACE. AT THIS TIME IT LOOKS TO BE A COUPLE TENTHS OF
AN INCH OF ICE ACCUMULATION...BUT IT WILL OCCUR DURING MORNING RUSH
HOUR. AS WARMER AIR IS DRAGGED DOWN WE WILL TRANSITION TO A MOSTLY
RAIN EVENT DURING THE DAY WITH A LITTLE WRAP AROUND SNOW ONCE THE
COLD FRONT MOVES THROUGH. THIS SYSTEM HAS MUCH MORE MOISTURE TO
WORK WITH THAN WE HAVE HAD LATELY...AND THIS WILL RESULT IN PLENTY
OF SNOW MELT AND POSSIBLY ICE JAM ISSUES.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
SHORT TERM.../THROUGH WEDNESDAY MORNING/...WIDESPREAD IFR AND LIFR
EXPECTED S OF THE FOOTHILLS THRU THIS EVENING. N OF THE MTNS IFR
CONDITIONS WILL BE MORE VARIABLE AS DOWNSLOPING DRIES OUT THE AIR
MASS. CONDITIONS WILL QUICKLY IMPROVE FROM S TO N AFTER MIDNIGHT.
LONG TERM...ADDITIONAL SNOW IS FORECAST FOR WEDNESDAY AFTERNOON
INTO THURSDAY MORNING...AND WILL PRODUCE LIFR CEILINGS AND
VISIBILITIES. WIDESPREAD MIXED PRECIPITATION INCLUDING FREEZING
RAIN AND RAIN WILL CREATE POOR FLYING CONDITIONS THURSDAY NIGHT
INTO FRIDAY.
&&
.MARINE...
SHORT TERM...GALES REMAIN UP FOR THE OUTER WATERS...WITH SCA
CONDITIONS EXPECTED IN THE BAYS. WINDS AND SEAS GRADUALLY SUBSIDE
INTO WED MORNING.
LONG TERM...SMALL CRAFT ADVISORIES MAY BE NEEDED AT TIMES THROUGH
FRIDAY WITH GUSTS AROUND 25-30 KTS AND WAVES IN THE 4-6 FT
RANGE...MAINLY OUTSIDE THE BAYS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING UNTIL 4 AM EST WEDNESDAY FOR MEZ018>020-
023>026.
WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR
MEZ012>014-021-022-027-028.
NH...WINTER STORM WARNING UNTIL 4 AM EST WEDNESDAY FOR NHZ006-009.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR
NHZ002>005-007.
WINTER STORM WARNING UNTIL 1 AM EST WEDNESDAY FOR NHZ008-010-
013-014.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST WEDNESDAY FOR ANZ151-153.
GALE WARNING UNTIL 4 AM EST WEDNESDAY FOR ANZ150-152-154.
&&
$$
ES
AREA FORECAST DISCUSSION
NWS GRAY ME
328 PM EST TUE FEB 18 2014
.SYNOPSIS...
LOW PRESSURE DEEPENS OFF THE NEW ENGLAND COAST AND MOVE OVER THE
GULF OF MAINE TONIGHT BEFORE MOVING INTO THE CANADIAN MARITIMES.
A COLD FRONT WILL SWING IN FROM THE WEST ON WEDNESDAY AND LOW
PRESSURE WILL DEVELOP ON THE FRONT AS IT PUSHES INTO THE GULF OF
MAINE WEDNESDAY EVENING. LOW PRESSURE WILL QUICKLY SHIFT EAST INTO
THE MARITIMES WEDNESDAY NIGHT. HIGH PRESSURE BUILD SIN FROM
THE WEST ON THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE REGION
THURSDAY NIGHT AND IS QUICKLY FOLLOWED BY A COLD FRONT FRIDAY.
HIGH PRESSURE BUILDS SOUTH OF NEW ENGLAND FRIDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
LOW PRES IS RAPIDLY DEVELOPING AS EXPECTED OVER SRN NEW ENGLAND
COAST ATTM. BASED ON RADAR AND SFC OBSERVATIONS...IT WOULD SEEM AS
IF LOW PRES WILL TRACK JUST N OF KPYM AND INTO THE GULF OF ME.
HEAVY SNFL HAS WORKED INTO SRN NH AND ADJACENT SWRN ME...WITH
RATES APPROACHING 1 TO 3 INCHES PER HOUR. SNFL TOTALS ARE ALREADY
PUSHING 4 TO 6 OR MORE ACROSS PARTS OF INTERIOR ROCKINGHAM COUNTY.
BASED ON MODEL PROGS AND REPORTS...FEEL THAT THIS IS THE AREA NOW
IN LINE FOR HIGHEST AMOUNTS IN THE CWFA. HAVE INCREASED QPF AND
SNFL FORECAST FOR THIS AREA. FOR THE REST OF THE AREA USED A BLEND
OF THE ECMWF...NAM12...RAP...AND NERFC QPF. THIS SHIFTED THE
HEAVIEST SN A LITTLE EWD FROM PREVIOUS FORECAST. SNFL AMOUNTS
STILL MATCHED HEADLINES WELL...SO THEY WILL REMAIN AS IS.
ELY WINDS HAVE ALSO WARMED THE IMMEDIATE COAST AOA FREEZING.
DESPITE THE WARM TEMPS...DEW POINT DEPRESSIONS WILL ALLOW WET BULB
COOLING TO KEEP PCPN MOSTLY SN. HOWEVER...IT MAY BE WETTER IN
NATURE AND CLING TO POWER LINES/TREES LEADING TO SCT POWER
OUTAGES. ELY WINDS ARE ALSO DOWNSLOPING ON THE N SIDE OF THE
WHITES...DRYING OUT THE COLUMN. SN WILL LIKELY STRUGGLE TO REACH
THE GROUND AT TIMES IN THE FAR N.
AS FOR SRN NH INTO SWRN ME...HEAVY SNFL REMAINS IN THE FORECAST
INTO THE EVENING. RAP CONTINUES TO SHOW FORECAST SOUNDINGS FROM
KCON TO NEAR KPWM APPROACHING A MAUL...MOIST ABSOLUTELY UNSTABLE
LAYER. MODEL GUIDANCE HAS AN AREA OF 6 TO 7 DEG/KM LAPSE RATES
ALOFT WORKING INTO THE REGION THRU THE EVENING. THIS KIND OF
INSTABILITY WOULD BE FAVORABLE FOR CONVECTION IN THE WARM
SEASON...LET ALONE FEBRUARY. THERE HAVE BEEN NO RECENT REPORTS OF
LIGHTNING...BUT WOULD NOT BE SURPRISED TO SEE A FEW IN THE NEXT
COUPLE OF HOURS. CONSIDERING THE SNFL OCCURRING ATTM IN SERN
NH...SEE NO REASON WHY THIS TREND WON/T THEN CONTINUE FOR THE NEXT
SEVERAL HOURS INTO SWRN ME. THIS IS ALL ONGOING AS MID LEVEL LOW
CENTER QUICKLY SPIN UP...MAXIMIZING DYNAMICS. AS THESE MATURE THIS
EVENING...SN WILL GRADUALLY TAPER TO MORE MODEST RATES. AS FORCING
SHIFTS EWD...SN WILL RAPIDLY END FROM S TO N AROUND MIDNIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH TUESDAY/...
AS SOON AS TONIGHT`S STORM LIFTS INTO THE CANADIAN MARITIMES...
ANOTHER SHORT WAVE QUICKLY FOLLOWS ON ITS HEELS...FOLLOWING A
SIMILAR PATH. SURFACE LOW PRESSURE DEEPENS OVER THE GULF OF MAINE
WEDNESDAY AFTERNOON INTO THURSDAY MORNING. THIS STORM IS FORMING A
LITTLE TOO FAR OFFSHORE TO ACCOUNT FOR MORE THAN 1-3 INCHES AS IT
MOVES QUICKLY BY.
TEMPERATURES WILL BE IN THE MID 30S TO MID 40S WEDNESDAY THROUGH
FRIDAY AS WARM AIR ADVECTION IS REINFORCED EVERY 18 HRS OR SO.
THE TIMING OF THESE WAVES AS WELL AS NEAR ZONAL FLOW ALOFT WILL
KEEP ANY COLD AIR FROM TAKING HOLD FOR MOST OF THE WEEK.
HOWEVER...SOME COLDER AIR DOES MANAGE TO SNEAK IN BEHIND A COLD
FRONT ON FRIDAY. THIS WILL BE PRECEDED BY A WARM FRONT FRIDAY
MORNING. TEMPERATURES AT THE ONSET OF THIS PRECIPITATION EVENT
SUPPORTS A LARGE SWATH OF FREEZING RAIN AND POSSIBLY SOME SLEET
FRIDAY MORNING AS WARMER AIR OVERRIDES FREEZING TEMPERATURES
NEAR THE SURFACE. AT THIS TIME IT LOOKS TO BE A COUPLE TENTHS OF
AN INCH OF ICE ACCUMULATION...BUT IT WILL OCCUR DURING MORNING RUSH
HOUR. AS WARMER AIR IS DRAGGED DOWN WE WILL TRANSITION TO A MOSTLY
RAIN EVENT DURING THE DAY WITH A LITTLE WRAP AROUND SNOW ONCE THE
COLD FRONT MOVES THROUGH. THIS SYSTEM HAS MUCH MORE MOISTURE TO
WORK WITH THAN WE HAVE HAD LATELY...AND THIS WILL RESULT IN PLENTY
OF SNOW MELT AND POSSIBLY ICE JAM ISSUES.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
SHORT TERM.../THROUGH WEDNESDAY MORNING/...WIDESPREAD IFR AND LIFR
EXPECTED S OF THE FOOTHILLS THRU THIS EVENING. N OF THE MTNS IFR
CONDITIONS WILL BE MORE VARIABLE AS DOWNSLOPING DRIES OUT THE AIR
MASS. CONDITIONS WILL QUICKLY IMPROVE FROM S TO N AFTER MIDNIGHT.
LONG TERM...ADDITIONAL SNOW IS FORECAST FOR WEDNESDAY AFTERNOON
INTO THURSDAY MORNING...AND WILL PRODUCE LIFR CEILINGS AND
VISIBILITIES. WIDESPREAD MIXED PRECIPITATION INCLUDING FREEZING
RAIN AND RAIN WILL CREATE POOR FLYING CONDITIONS THURSDAY NIGHT
INTO FRIDAY.
&&
.MARINE...
SHORT TERM...GALES REMAIN UP FOR THE OUTER WATERS...WITH SCA
CONDITIONS EXPECTED IN THE BAYS. WINDS AND SEAS GRADUALLY SUBSIDE
INTO WED MORNING.
LONG TERM...SMALL CRAFT ADVISORIES MAY BE NEEDED AT TIMES THROUGH
FRIDAY WITH GUSTS AROUND 25-30 KTS AND WAVES IN THE 4-6 FT
RANGE...MAINLY OUTSIDE THE BAYS.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING UNTIL 4 AM EST WEDNESDAY FOR MEZ018>020-
023>026.
WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR
MEZ012>014-021-022-027-028.
NH...WINTER STORM WARNING UNTIL 4 AM EST WEDNESDAY FOR NHZ006-009.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR
NHZ002>005-007-014.
WINTER STORM WARNING UNTIL 1 AM EST WEDNESDAY FOR NHZ008-010-
013.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST WEDNESDAY FOR ANZ151-153.
GALE WARNING UNTIL 4 AM EST WEDNESDAY FOR ANZ150-152-154.
&&
$$
LEGRO/HANES
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
1033 AM EST TUE FEB 18 2014
.SYNOPSIS...
LOW PRESSURE APPROACHING FROM THE WEST WILL REDEVELOP OFF THE NEW
ENGLAND COAST THIS AFTERNOON AND WILL RACE INTO THE MARITIMES THIS
EVENING. A COLD FRONT WILL SWING IN FROM THE WEST ON WEDNESDAY AND
LOW PRESSURE WILL DEVELOP ON THE FRONT AS IT PUSHES INTO THE GULF OF
MAINE WEDNESDAY EVENING. LOW PRESSURE WILL QUICKLY SHIFT EAST INTO
THE MARITIMES WEDNESDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE
WEST ON THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE REGION
THURSDAY NIGHT AND WILL BE QUICKLY FOLLOWED BY A COLD FRONT ON
FRIDAY. HIGH PRESSURE WILL BUILD SOUTH OF NEW ENGLAND FRIDAY NIGHT
AND WILL SHIFT OFFSHORE ON SATURDAY. A COLD FRONT FRONT WILL CROSS
THE REGION SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...A FEW MINOR CHANGES TO THE GRIDS TO BRING FORECAST IN
LINE WITH CURRENT OBSERVATIONAL TRENDS. PROGRESSION OF POP
LOOKS TO BE ON TRACK ATTM...SO DIDN/T CHANGE TOO MUCH FROM
PREVIOUS. MESOSCALE MODEL GUIDANCE CONTINUES TO BE IN STRONG
AGREEMENT ON EVOLUTION OF LOW PRES THIS AFTERNOON. FORECAST
SOUNDINGS FROM THESE MODELS CONTINUE TO INDICATE HINTS OF A
MAUL...MOIST ABSOLUTELY UNSTABLE LAYER...SO THERE REMAINS THE
THREAT OF POTENTIALLY INTENSE SNFL RATES LATER TODAY.
PREVIOUSLY..
A VERY STRONG SHORT WAVE TROUGH CROSSING THE LOWER GREAT LAKES
EARLY THIS MORNING WILL CONTINUE EASTWARD AND WILL AID IN RAPID
CYCLOGENESIS OVER SOUTHERN NEW ENGLAND BY THIS AFTERNOON. LIGHT
SNOW IS ALREADY OCCURRING IN THE WAA IN ADVANCE OF THIS SHORT WAVE
ACROSS NORTHEAST PA INTO CENTRAL NY. THIS ACTIVITY WILL LIKELY
PUSH INTO NORTHERN NEW ENGLAND LATER THIS MORNING BUT SHOULD
REMAIN LIGHT.
THE REAL SHOW LOOKS TO GET GOING LATE THIS MORNING AND EARLY
AFTERNOON AS LOW PRESSURE DEVELOP OVER LONG ISLAND NY OR SOUTHERN
NEW ENGLAND AS MID LEVEL LOW PRESSURE BEGINS TO CLOSE OFF. AS THIS
HAPPENS...STRONG DYNAMICS AND KINEMATICS WILL GO INTO MOTION AND
ALLOW A HEAVY PRECIPITATION SHIELD TO BLOSSOM OVER SOUTHERN NEW
ENGLAND AND HEAD NNEWD. THIS OCCURS AS STRONG ISENTROPIC LIFT
DEVELOPS VIA STRONG EASTERLY INFLOW UPGLIDING INTO A
STRENGTHENING DEFORMATION ZONE OVER NEW ENGLAND. THE RESULTANT
COMMA HEAD THAT DEVELOPS OVER SOUTHERN NEW ENGLAND SHOULD THEN
RIDE NNEWD INTO SOUTHERN NH AND SOUTHERNMOST ME BY EARLY
AFTERNOON...WHICH WILL THEN SPREAD NEWD FROM THERE...AFFECTING THE
REST OF THE WARNING AREA MAINLY LATE THIS AFTERNOON AND EVENING.
THE VARIOUS 00Z MODELS...INCLUDING LATEST RUNS OF THE RAP AND HRRR
ARE ALL IN GENERALLY GOOD AGREEMENT WITH THE DEVELOPING SYSTEM.
HOWEVER...THERE ARE STILL SOME DIFFERENCES IN HOW FAR WEST THE
HEAVIEST SNOW BANDING WILL EXTEND. THE CURRENT CONSENSUS IS FOR
THE AXIS OF MAX QPF AND RESULTANT SNOWFALL TO OCCUR ACROSS THE
SOUTHEASTERN QUARTER OF NEW HAMPSHIRE NORTHWARD TO THE COASTAL
PLAIN OF MAINE TO JUST SOUTH OF AUGUSTA. THE BANDING THEN WANES AS
THE SYSTEM STOPS DEEPENING...THEREFORE...LOWER AMOUNTS ARE
CURRENTLY EXPECTED NORTHEAST OF THE WARNING AREA. IT IS WORTH
NOTING AT THIS TIME THAT THE HIGHER RESOLUTION MODELS SUCH AS THE
RAP AND VARIOUS 4KM WRF MODELS ARE MORE POTENT...WITH MORE QPF
OVER A WIDER AREA. WHILE THEY ARE LIKELY SOMEWHAT OVERDONE...THIS
SITUATION MAY LEND MORE CREDENCE TO THEM AS THEY MAY BE CAPTURING
THE MESOSCALE PROCESSES BETTER THAN THE LOWER RESOLUTION MODELS.
THEREFORE...THE DAY SHIFT WILL HAVE TO ASSESS TRENDS AND SEE IF
WARNINGS AND ADVISORIES WILL HAVE TO BE ADJUSTED.
ON THE IMMEDIATE COAST...BOUNDARY LAYER TEMPERATURE ISSUES MAY
LEAD TO LOWER SNOWFALL AMOUNTS...HOWEVER...ONCE THE BANDING SETS
IN...SNOW SHOULD BE THE FAVORED PRECIP TYPE. THE SNOW MAY BE WET
THERE...SO SOME POWER OUTAGES POSSIBLE.
FORECAST STORM TOTAL SNOWFALL AMOUNTS ARE NOT EXPECTED TO BE
OVERLY HIGH WITH THIS SYSTEM...MAINLY IN THE 4-8 INCH RANGE WITH
LOCALLY HIGHER AMOUNTS POSSIBLE IN PERSISTENT BANDING.
HOWEVER...SNOWFALL RATES OF 1-3 INCHES PER HOUR FOR A
TIME...PROBABLY DURING THE EVENING COMMUTE WILL LIKELY ALLOW FOR A
HIGH-IMPACT EVENT. ISOLD THUNDER MAY EVEN OCCUR IN THE HEAVIEST
BANDING.
THE SNOW WILL TAPER OFF EARLY THIS MORNING ACROSS SOUTHERNMOST
ZONES...AND FINALLY END ON THE MID COAST AFTER MIDNIGHT.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
THE SNOW WILL TAPER OFF EARLY THIS MORNING ACROSS SOUTHERNMOST
ZONES...AND FINALLY END ON THE MID COAST AFTER MIDNIGHT.
NO REST FOR THE WEARY AS ANOTHER SYSTEM LOOKS TO AFFECT THE AREA
ON WEDNESDAY...MAINLY DURING THE AFTERNOON. THIS SYSTEM WILL BE
WEAKER AND BOUNDARY LAYER TEMPERATURES WARMER THAN TODAY/S SYSTEM.
HOWEVER...MODELS ARE SPINNING UP LOW PRESSURE CLOSE TO THE COAST
FASTER THAT PREVIOUS RUNS...ALLOWING FOR THE POTENTIAL FOR HEAVY
PRECIPITATION WED AFTERNOON AND EVENING. IF THIS
OCCURS...ESPECIALLY LIKELY ECMWF IS SHOWING...MORE WEATHER
HEADLINES MAY BE NEEDED...ESPECIALLY NORTHEAST OF PORTLAND TO THE
MID COAST.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
LOW PRESSURE WILL SPIN UP JUST OFFSHORE WEDNESDAY EVENING. IF
MODEL TRENDS CONTINUE LOW PRESSURE MAY SPIN UP QUICK ENOUGH TO
WARRANT ADVISORIES IN MID COAST MAINE AND FAR EASTERN COUNTIES OF
THE FORECAST AREA. QPF FROM THE NEW ECMWF HAS INCREASED
SIGNIFICANTLY FROM LAST NIGHT IN THESE AREAS.
IN ANY CASE...LOW PRESSURE WILL QUICKLY RACE INTO THE MARITIMES
BEFORE MIDNIGHT BRINGING A QUICK END TO PRECIP ACROSS THE AREA.
EXPECT CLEARING DOWNWIND OF THE MOUNTAINS AFTER MIDNIGHT BUT
INCREASING UPSLOPE FLOW AND LINGERING LOW LEVEL MOISTURE WILL KEEP
CLOUDS AND A CHANCE OF SNOW SHOWERS IN THE FORECAST FOR THE NORTH
INTO THURSDAY MORNING.
NARROW RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST ON THURSDAY
PROVIDING MOSTLY SUNNY SKIES FOR MOST OF THE AREA. EXPECT LINGERING
CLOUDS IN THE MOUNTAINS TO GRADUALLY DIMINISH DURING THE DAY. WILL
ACTUALLY SEE HIGHS CLIMBING ABOVE NORMAL WITH HIGHS REACHING THE MID
30S TO LOWER 40S NORTH AND LOWER TO MID 40S SOUTH.
HIGH PRESSURE WILL SHIFT OFFSHORE EARLY THURSDAY EVENING AND A WARM
FRONT WILL LIFT NORTH INTO THE REGION OVERNIGHT. THIS WILL SET THE
STAGE FOR ANOTHER ROUND OF MIXED PRECIPITATION IN SOUTHERN ZONES AND
SNOW CHANGING TO MIXED PRECIP IN NORTHERN ZONES BEFORE TAPERING OFF
TOWARD FRIDAY MORNING. QPF NOT VERY IMPRESSIVE WITH THIS INITIAL
BURST OF OVER-RUNNING PRECIP BUT WILL LIKELY CAUSE TRAVEL PROBLEMS
OVERNIGHT AND DURING THE MORNING COMMUTE ON FRIDAY. COLD FRONT
APPROACHING FROM THE WEST WILL BRING A ROUND OF SHOWERS TO THE
REGION LATE FRIDAY MORNING THROUGH MID AFTERNOON. SHOULD BE A QUICK
HITTER WITH PRECIP PUSHING EAST OF THE FORECAST AREA BY MID
AFTERNOON.
WEAK HIGH PRESSURE BUILDING SOUTH OF NEW ENGLAND FRIDAY NIGHT SHOULD
RESULT IN MOSTLY CLEAR NIGHT WITH SEASONABLE TEMPS. HIGH PRESSURE
WILL QUICKLY SHIFT OFFSHORE SOUTH OF NEW ENGLAND SATURDAY MORNING.
EXPECT A MOSTLY SUNNY START TO THE DAY BEFORE CLOUDS AHEAD OF AN
APPROACHING COLD FRONT PUSH IN FROM THE WEST IN THE AFTERNOON. AT
THIS POINT IN TIME...APPEARS ANY ASSOCIATED PRECIP WILL HOLD OFF
UNTIL SATURDAY EVENING WITH A BRIEF SNOW SHOWER POSSIBLE WITH THE
FROPA. EXPECTING LITTLE IF ANY ACCUMULATION AS THIS MOISTURE
STARVED SYSTEM QUICKLY BLOWS THROUGH OVERNIGHT.
BEHIND THE FRONT ANOTHER SHOT OF ARCTIC AIR WILL INVADE NEW ENGLAND
FOR THE LAST HALF OF THE WEEKEND AND THE BEGINNING OF NEXT WEEK.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...VFR THIS MORNING GIVES WAY TO LIFR IN HEAVY SNOW THIS
AFTERNOON AND EVENING. MVFR TO VFR RETURNS AFTER MIDNIGHT TONIGHT.
HOWEVER...MVFR OF LOWER CONDITIONS ONCE AGAIN POSSIBLE IN SNOW
AND/OR RAIN WEDNESDAY...ESPECIALLY IN THE AFTERNOON AND EVENING.
LONG TERM...VFR THURSDAY. MVFR/IFR CEILINGS DEVELOPING THURSDAY
NIGHT AND PERSISTING THROUGH FRIDAY. VFR FRIDAY NIGHT THROUGH
SATURDAY.
&&
.MARINE...
SHORT TERM...GALES FOR THE OCEAN WATERS THIS AFTERNOON AND EVENING
AS LOW PRESSURE CRANKS UP IN THE GULF OF MAINE. SCA RETURNS LATER
TONIGHT AND FOR WEDNESDAY.
LONG TERM...SCA`S LIKELY WEDNESDAY NIGHT THROUGH EARLY THURSDAY.
GALES POSSIBLE ON FRIDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING UNTIL 4 AM EST WEDNESDAY FOR MEZ018>020-
023>026.
WINTER WEATHER ADVISORY UNTIL 4 AM EST WEDNESDAY FOR
MEZ012>014-021-022-027-028.
NH...WINTER STORM WARNING UNTIL 4 AM EST WEDNESDAY FOR NHZ006-009.
WINTER WEATHER ADVISORY UNTIL 1 AM EST WEDNESDAY FOR
NHZ002>005-007-014.
WINTER STORM WARNING UNTIL 1 AM EST WEDNESDAY FOR NHZ008-010-
013.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST WEDNESDAY FOR ANZ151-153.
GALE WARNING UNTIL 4 AM EST WEDNESDAY FOR ANZ150-152-154.
&&
$$
NEAR TERM...LEGRO
AREA FORECAST DISCUSSION
NWS GRAY ME
710 AM EST TUE FEB 18 2014
.SYNOPSIS...
LOW PRESSURE APPROACHING FROM THE WEST WILL REDEVELOP OFF THE NEW
ENGLAND COAST THIS AFTERNOON AND WILL RACE INTO THE MARITIMES THIS
EVENING. A COLD FRONT WILL SWING IN FROM THE WEST ON WEDNESDAY AND
LOW PRESSURE WILL DEVELOP ON THE FRONT AS IT PUSHES INTO THE GULF OF
MAINE WEDNESDAY EVENING. LOW PRESSURE WILL QUICKLY SHIFT EAST INTO
THE MARITIMES WEDNESDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE
WEST ON THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE REGION
THURSDAY NIGHT AND WILL BE QUICKLY FOLLOWED BY A COLD FRONT ON
FRIDAY. HIGH PRESSURE WILL BUILD SOUTH OF NEW ENGLAND FRIDAY NIGHT
AND WILL SHIFT OFFSHORE ON SATURDAY. A COLD FRONT FRONT WILL CROSS
THE REGION SATURDAY NIGHT.
&&
.NEAR TERM /TODAY THROUGH MIDNIGHT TONIGHT/...
710 AM UPDATE...NO CHANGES TO THE LATEST FORECAST. THINGS ARE
CURRENTLY DEVELOPING AS PLANNED. RAP AND HRRR CONTINUE TO DEVELOP
HEAVY SNOWFALL FROM SOUTH TO NORTH STARTING EARLY THIS AFTERNOON.
PREVIOUSLY..
A VERY STRONG SHORT WAVE TROUGH CROSSING THE LOWER GREAT LAKES
EARLY THIS MORNING WILL CONTINUE EASTWARD AND WILL AID IN RAPID
CYCLOGENESIS OVER SOUTHERN NEW ENGLAND BY THIS AFTERNOON. LIGHT
SNOW IS ALREADY OCCURRING IN THE WAA IN ADVANCE OF THIS SHORT WAVE
ACROSS NORTHEAST PA INTO CENTRAL NY. THIS ACTIVITY WILL LIKELY
PUSH INTO NORTHERN NEW ENGLAND LATER THIS MORNING BUT SHOULD
REMAIN LIGHT.
THE REAL SHOW LOOKS TO GET GOING LATE THIS MORNING AND EARLY
AFTERNOON AS LOW PRESSURE DEVELOP OVER LONG ISLAND NY OR SOUTHERN
NEW ENGLAND AS MID LEVEL LOW PRESSURE BEGINS TO CLOSE OFF. AS THIS
HAPPENS...STRONG DYNAMICS AND KINEMATICS WILL GO INTO MOTION AND
ALLOW A HEAVY PRECIPITATION SHIELD TO BLOSSOM OVER SOUTHERN NEW
ENGLAND AND HEAD NNEWD. THIS OCCURS AS STRONG ISENTROPIC LIFT
DEVELOPS VIA STRONG EASTERLY INFLOW UPGLIDING INTO A
STRENGTHENING DEFORMATION ZONE OVER NEW ENGLAND. THE RESULTANT
COMMA HEAD THAT DEVELOPS OVER SOUTHERN NEW ENGLAND SHOULD THEN
RIDE NNEWD INTO SOUTHERN NH AND SOUTHERNMOST ME BY EARLY
AFTERNOON...WHICH WILL THEN SPREAD NEWD FROM THERE...AFFECTING THE
REST OF THE WARNING AREA MAINLY LATE THIS AFTERNOON AND EVENING.
THE VARIOUS 00Z MODELS...INCLUDING LATEST RUNS OF THE RAP AND HRRR
ARE ALL IN GENERALLY GOOD AGREEMENT WITH THE DEVELOPING SYSTEM.
HOWEVER...THERE ARE STILL SOME DIFFERENCES IN HOW FAR WEST THE
HEAVIEST SNOW BANDING WILL EXTEND. THE CURRENT CONSENSUS IS FOR
THE AXIS OF MAX QPF AND RESULTANT SNOWFALL TO OCCUR ACROSS THE
SOUTHEASTERN QUARTER OF NEW HAMPSHIRE NORTHWARD TO THE COASTAL
PLAIN OF MAINE TO JUST SOUTH OF AUGUSTA. THE BANDING THEN WANES AS
THE SYSTEM STOPS DEEPENING...THEREFORE...LOWER AMOUNTS ARE
CURRENTLY EXPECTED NORTHEAST OF THE WARNING AREA. IT IS WORTH
NOTING AT THIS TIME THAT THE HIGHER RESOLUTION MODELS SUCH AS THE
RAP AND VARIOUS 4KM WRF MODELS ARE MORE POTENT...WITH MORE QPF
OVER A WIDER AREA. WHILE THEY ARE LIKELY SOMEWHAT OVERDONE...THIS
SITUATION MAY LEND MORE CREDENCE TO THEM AS THEY MAY BE CAPTURING
THE MESOSCALE PROCESSES BETTER THAN THE LOWER RESOLUTION MODELS.
THEREFORE...THE DAY SHIFT WILL HAVE TO ASSESS TRENDS AND SEE IF
WARNINGS AND ADVISORIES WILL HAVE TO BE ADJUSTED.
ON THE IMMEDIATE COAST...BOUNDARY LAYER TEMPERATURE ISSUES MAY
LEAD TO LOWER SNOWFALL AMOUNTS...HOWEVER...ONCE THE BANDING SETS
IN...SNOW SHOULD BE THE FAVORED PRECIP TYPE. THE SNOW MAY BE WET
THERE...SO SOME POWER OUTAGES POSSIBLE.
FORECAST STORM TOTAL SNOWFALL AMOUNTS ARE NOT EXPECTED TO BE
OVERLY HIGH WITH THIS SYSTEM...MAINLY IN THE 4-8 INCH RANGE WITH
LOCALLY HIGHER AMOUNTS POSSIBLE IN PERSISTENT BANDING.
HOWEVER...SNOWFALL RATES OF 1-3 INCHES PER HOUR FOR A
TIME...PROBABLY DURING THE EVENING COMMUTE WILL LIKELY ALLOW FOR A
HIGH-IMPACT EVENT. ISOLD THUNDER MAY EVEN OCCUR IN THE HEAVIEST
BANDING.
THE SNOW WILL TAPER OFF EARLY THIS MORNING ACROSS SOUTHERNMOST
ZONES...AND FINALLY END ON THE MID COAST AFTER MIDNIGHT.
&&
.SHORT TERM /MIDNIGHT TONIGHT THROUGH 6 PM WEDNESDAY/...
THE SNOW WILL TAPER OFF EARLY THIS MORNING ACROSS SOUTHERNMOST
ZONES...AND FINALLY END ON THE MID COAST AFTER MIDNIGHT.
NO REST FOR THE WEARY AS ANOTHER SYSTEM LOOKS TO AFFECT THE AREA
ON WEDNESDAY...MAINLY DURING THE AFTERNOON. THIS SYSTEM WILL BE
WEAKER AND BOUNDARY LAYER TEMPERATURES WARMER THAN TODAY/S SYSTEM.
HOWEVER...MODELS ARE SPINNING UP LOW PRESSURE CLOSE TO THE COAST
FASTER THAT PREVIOUS RUNS...ALLOWING FOR THE POTENTIAL FOR HEAVY
PRECIPITATION WED AFTERNOON AND EVENING. IF THIS
OCCURS...ESPECIALLY LIKELY ECMWF IS SHOWING...MORE WEATHER
HEADLINES MAY BE NEEDED...ESPECIALLY NORTHEAST OF PORTLAND TO THE
MID COAST.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
LOW PRESSURE WILL SPIN UP JUST OFFSHORE WEDNESDAY EVENING. IF
MODEL TRENDS CONTINUE LOW PRESSURE MAY SPIN UP QUICK ENOUGH TO
WARRANT ADVISORIES IN MID COAST MAINE AND FAR EASTERN COUNTIES OF
THE FORECAST AREA. QPF FROM THE NEW ECMWF HAS INCREASED
SIGNIFICANTLY FROM LAST NIGHT IN THESE AREAS.
IN ANY CASE...LOW PRESSURE WILL QUICKLY RACE INTO THE MARITIMES
BEFORE MIDNIGHT BRINGING A QUICK END TO PRECIP ACROSS THE AREA.
EXPECT CLEARING DOWNWIND OF THE MOUNTAINS AFTER MIDNIGHT BUT
INCREASING UPSLOPE FLOW AND LINGERING LOW LEVEL MOISTURE WILL KEEP
CLOUDS AND A CHANCE OF SNOW SHOWERS IN THE FORECAST FOR THE NORTH
INTO THURSDAY MORNING.
NARROW RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST ON THURSDAY
PROVIDING MOSTLY SUNNY SKIES FOR MOST OF THE AREA. EXPECT LINGERING
CLOUDS IN THE MOUNTAINS TO GRADUALLY DIMINISH DURING THE DAY. WILL
ACTUALLY SEE HIGHS CLIMBING ABOVE NORMAL WITH HIGHS REACHING THE MID
30S TO LOWER 40S NORTH AND LOWER TO MID 40S SOUTH.
HIGH PRESSURE WILL SHIFT OFFSHORE EARLY THURSDAY EVENING AND A WARM
FRONT WILL LIFT NORTH INTO THE REGION OVERNIGHT. THIS WILL SET THE
STAGE FOR ANOTHER ROUND OF MIXED PRECIPITATION IN SOUTHERN ZONES AND
SNOW CHANGING TO MIXED PRECIP IN NORTHERN ZONES BEFORE TAPERING OFF
TOWARD FRIDAY MORNING. QPF NOT VERY IMPRESSIVE WITH THIS INITIAL
BURST OF OVER-RUNNING PRECIP BUT WILL LIKELY CAUSE TRAVEL PROBLEMS
OVERNIGHT AND DURING THE MORNING COMMUTE ON FRIDAY. COLD FRONT
APPROACHING FROM THE WEST WILL BRING A ROUND OF SHOWERS TO THE
REGION LATE FRIDAY MORNING THROUGH MID AFTERNOON. SHOULD BE A QUICK
HITTER WITH PRECIP PUSHING EAST OF THE FORECAST AREA BY MID
AFTERNOON.
WEAK HIGH PRESSURE BUILDING SOUTH OF NEW ENGLAND FRIDAY NIGHT SHOULD
RESULT IN MOSTLY CLEAR NIGHT WITH SEASONABLE TEMPS. HIGH PRESSURE
WILL QUICKLY SHIFT OFFSHORE SOUTH OF NEW ENGLAND SATURDAY MORNING.
EXPECT A MOSTLY SUNNY START TO THE DAY BEFORE CLOUDS AHEAD OF AN
APPROACHING COLD FRONT PUSH IN FROM THE WEST IN THE AFTERNOON. AT
THIS POINT IN TIME...APPEARS ANY ASSOCIATED PRECIP WILL HOLD OFF
UNTIL SATURDAY EVENING WITH A BRIEF SNOW SHOWER POSSIBLE WITH THE
FROPA. EXPECTING LITTLE IF ANY ACCUMULATION AS THIS MOISTURE
STARVED SYSTEM QUICKLY BLOWS THROUGH OVERNIGHT.
BEHIND THE FRONT ANOTHER SHOT OF ARCTIC AIR WILL INVADE NEW ENGLAND
FOR THE LAST HALF OF THE WEEKEND AND THE BEGINNING OF NEXT WEEK.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...VFR THIS MORNING GIVES WAY TO LIFR IN HEAVY SNOW THIS
AFTERNOON AND EVENING. MVFR TO VFR RETURNS AFTER MIDNIGHT TONIGHT.
HOWEVER...MVFR OF LOWER CONDITIONS ONCE AGAIN POSSIBLE IN SNOW
AND/OR RAIN WEDNESDAY...ESPECIALLY IN THE AFTERNOON AND EVENING.
LONG TERM...VFR THURSDAY. MVFR/IFR CEILINGS DEVELOPING THURSDAY
NIGHT AND PERSISTING THROUGH FRIDAY. VFR FRIDAY NIGHT THROUGH
SATURDAY.
&&
.MARINE...
SHORT TERM...GALES FOR THE OCEAN WATERS THIS AFTERNOON AND EVENING
AS LOW PRESSURE CRANKS UP IN THE GULF OF MAINE. SCA RETURNS LATER
TONIGHT AND FOR WEDNESDAY.
LONG TERM...SCA`S LIKELY WEDNESDAY NIGHT THROUGH EARLY THURSDAY.
GALES POSSIBLE ON FRIDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING FROM 10 AM THIS MORNING TO 4 AM EST
WEDNESDAY FOR MEZ018>020-023>026.
WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 AM EST
WEDNESDAY FOR MEZ012>014-021-022-027-028.
NH...WINTER STORM WARNING FROM 10 AM THIS MORNING TO 4 AM EST
WEDNESDAY FOR NHZ006-009.
WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 1 AM EST
WEDNESDAY FOR NHZ002>005-007-014.
WINTER STORM WARNING FROM 7 AM THIS MORNING TO 1 AM EST
WEDNESDAY FOR NHZ008-010-013.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 AM EST
WEDNESDAY FOR ANZ151-153.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 4 AM EST WEDNESDAY
FOR ANZ150-152-154.
&&
$$
NEAR/SHORT TERM...EKSTER
AREA FORECAST DISCUSSION...CORRECTED
NWS GRAY ME
418 AM EST TUE FEB 18 2014
.SYNOPSIS...
LOW PRESSURE APPROACHING FROM THE WEST WILL REDEVELOP OFF THE NEW
ENGLAND COAST THIS AFTERNOON AND WILL RACE INTO THE MARITIMES THIS
EVENING. A COLD FRONT WILL SWING IN FROM THE WEST ON WEDNESDAY AND
LOW PRESSURE WILL DEVELOP ON THE FRONT AS IT PUSHES INTO THE GULF OF
MAINE WEDNESDAY EVENING. LOW PRESSURE WILL QUICKLY SHIFT EAST INTO
THE MARITIMES WEDNESDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE
WEST ON THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE REGION
THURSDAY NIGHT AND WILL BE QUICKLY FOLLOWED BY A COLD FRONT ON
FRIDAY. HIGH PRESSURE WILL BUILD SOUTH OF NEW ENGLAND FRIDAY NIGHT
AND WILL SHIFT OFFSHORE ON SATURDAY. A COLD FRONT FRONT WILL CROSS
THE REGION SATURDAY NIGHT.
&&
.NEAR TERM /TODAY THROUGH MIDNIGHT TONIGHT/...
A VERY STRONG SHORT WAVE TROUGH CROSSING THE LOWER GREAT LAKES
EARLY THIS MORNING WILL CONTINUE EASTWARD AND WILL AID IN RAPID
CYCLOGENESIS OVER SOUTHERN NEW ENGLAND BY THIS AFTERNOON. LIGHT
SNOW IS ALREADY OCCURRING IN THE WAA IN ADVANCE OF THIS SHORT WAVE
ACROSS NORTHEAST PA INTO CENTRAL NY. THIS ACTIVITY WILL LIKELY
PUSH INTO NORTHERN NEW ENGLAND LATER THIS MORNING BUT SHOULD
REMAIN LIGHT.
THE REAL SHOW LOOKS TO GET GOING LATE THIS MORNING AND EARLY
AFTERNOON AS LOW PRESSURE DEVELOP OVER LONG ISLAND NY OR SOUTHERN
NEW ENGLAND AS MID LEVEL LOW PRESSURE BEGINS TO CLOSE OFF. AS THIS
HAPPENS...STRONG DYNAMICS AND KINEMATICS WILL GO INTO MOTION AND
ALLOW A HEAVY PRECIPITATION SHIELD TO BLOSSOM OVER SOUTHERN NEW
ENGLAND AND HEAD NNEWD. THIS OCCURS AS STRONG ISENTROPIC LIFT
DEVELOPS VIA STRONG EASTERLY INFLOW UPGLIDING INTO A
STRENGTHENING DEFORMATION ZONE OVER NEW ENGLAND. THE RESULTANT
COMMA HEAD THAT DEVELOPS OVER SOUTHERN NEW ENGLAND SHOULD THEN
RIDE NNEWD INTO SOUTHERN NH AND SOUTHERNMOST ME BY EARLY
AFTERNOON...WHICH WILL THEN SPREAD NEWD FROM THERE...AFFECTING THE
REST OF THE WARNING AREA MAINLY LATE THIS AFTERNOON AND EVENING.
THE VARIOUS 00Z MODELS...INCLUDING LATEST RUNS OF THE RAP AND HRRR
ARE ALL IN GENERALLY GOOD AGREEMENT WITH THE DEVELOPING SYSTEM.
HOWEVER...THERE ARE STILL SOME DIFFERENCES IN HOW FAR WEST THE
HEAVIEST SNOW BANDING WILL EXTEND. THE CURRENT CONSENSUS IS FOR
THE AXIS OF MAX QPF AND RESULTANT SNOWFALL TO OCCUR ACROSS THE
SOUTHEASTERN QUARTER OF NEW HAMPSHIRE NORTHWARD TO THE COASTAL
PLAIN OF MAINE TO JUST SOUTH OF AUGUSTA. THE BANDING THEN WANES AS
THE SYSTEM STOPS DEEPENING...THEREFORE...LOWER AMOUNTS ARE
CURRENTLY EXPECTED NORTHEAST OF THE WARNING AREA. IT IS WORTH
NOTING AT THIS TIME THAT THE HIGHER RESOLUTION MODELS SUCH AS THE
RAP AND VARIOUS 4KM WRF MODELS ARE MORE POTENT...WITH MORE QPF
OVER A WIDER AREA. WHILE THEY ARE LIKELY SOMEWHAT OVERDONE...THIS
SITUATION MAY LEND MORE CREDENCE TO THEM AS THEY MAY BE CAPTURING
THE MESOSCALE PROCESSES BETTER THAN THE LOWER RESOLUTION MODELS.
THEREFORE...THE DAY SHIFT WILL HAVE TO ASSESS TRENDS AND SEE IF
WARNINGS AND ADVISORIES WILL HAVE TO BE ADJUSTED.
ON THE IMMEDIATE COAST...BOUNDARY LAYER TEMPERATURE ISSUES MAY
LEAD TO LOWER SNOWFALL AMOUNTS...HOWEVER...ONCE THE BANDING SETS
IN...SNOW SHOULD BE THE FAVORED PRECIP TYPE. THE SNOW MAY BE WET
THERE...SO SOME POWER OUTAGES POSSIBLE.
FORECAST STORM TOTAL SNOWFALL AMOUNTS ARE NOT EXPECTED TO BE
OVERLY HIGH WITH THIS SYSTEM...MAINLY IN THE 4-8 INCH RANGE WITH
LOCALLY HIGHER AMOUNTS POSSIBLE IN PERSISTENT BANDING.
HOWEVER...SNOWFALL RATES OF 1-3 INCHES PER HOUR FOR A
TIME...PROBABLY DURING THE EVENING COMMUTE WILL LIKELY ALLOW FOR A
HIGH-IMPACT EVENT. ISOLD THUNDER MAY EVEN OCCUR IN THE HEAVIEST
BANDING.
THE SNOW WILL TAPER OFF EARLY THIS MORNING ACROSS SOUTHERNMOST
ZONES...AND FINALLY END ON THE MID COAST AFTER MIDNIGHT.
&&
.SHORT TERM /MIDNIGHT TONIGHT THROUGH 6 PM WEDNESDAY/...
THE SNOW WILL TAPER OFF EARLY THIS MORNING ACROSS SOUTHERNMOST
ZONES...AND FINALLY END ON THE MID COAST AFTER MIDNIGHT.
NO REST FOR THE WEARY AS ANOTHER SYSTEM LOOKS TO AFFECT THE AREA
ON WEDNESDAY...MAINLY DURING THE AFTERNOON. THIS SYSTEM WILL BE
WEAKER AND BOUNDARY LAYER TEMPERATURES WARMER THAN TODAY/S SYSTEM.
HOWEVER...MODELS ARE SPINNING UP LOW PRESSURE CLOSE TO THE COAST
FASTER THAT PREVIOUS RUNS...ALLOWING FOR THE POTENTIAL FOR HEAVY
PRECIPITATION WED AFTERNOON AND EVENING. IF THIS
OCCURS...ESPECIALLY LIKELY ECMWF IS SHOWING...MORE WEATHER
HEADLINES MAY BE NEEDED...ESPECIALLY NORTHEAST OF PORTLAND TO THE
MID COAST.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
LOW PRESSURE WILL SPIN UP JUST OFFSHORE WEDNESDAY EVENING. IF
MODEL TRENDS CONTINUE LOW PRESSURE MAY SPIN UP QUICK ENOUGH TO
WARRANT ADVISORIES IN MID COAST MAINE AND FAR EASTERN COUNTIES OF
THE FORECAST AREA. QPF FROM THE NEW ECMWF HAS INCREASED
SIGNIFICANTLY FROM LAST NIGHT IN THESE AREAS.
IN ANY CASE...LOW PRESSURE WILL QUICKLY RACE INTO THE MARITIMES
BEFORE MIDNIGHT BRINGING A QUICK END TO PRECIP ACROSS THE AREA.
EXPECT CLEARING DOWNWIND OF THE MOUNTAINS AFTER MIDNIGHT BUT
INCREASING UPSLOPE FLOW AND LINGERING LOW LEVEL MOISTURE WILL KEEP
CLOUDS AND A CHANCE OF SNOW SHOWERS IN THE FORECAST FOR THE NORTH
INTO THURSDAY MORNING.
NARROW RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST ON THURSDAY
PROVIDING MOSTLY SUNNY SKIES FOR MOST OF THE AREA. EXPECT LINGERING
CLOUDS IN THE MOUNTAINS TO GRADUALLY DIMINISH DURING THE DAY. WILL
ACTUALLY SEE HIGHS CLIMBING ABOVE NORMAL WITH HIGHS REACHING THE MID
30S TO LOWER 40S NORTH AND LOWER TO MID 40S SOUTH.
HIGH PRESSURE WILL SHIFT OFFSHORE EARLY THURSDAY EVENING AND A WARM
FRONT WILL LIFT NORTH INTO THE REGION OVERNIGHT. THIS WILL SET THE
STAGE FOR ANOTHER ROUND OF MIXED PRECIPITATION IN SOUTHERN ZONES AND
SNOW CHANGING TO MIXED PRECIP IN NORTHERN ZONES BEFORE TAPERING OFF
TOWARD FRIDAY MORNING. QPF NOT VERY IMPRESSIVE WITH THIS INITIAL
BURST OF OVER-RUNNING PRECIP BUT WILL LIKELY CAUSE TRAVEL PROBLEMS
OVERNIGHT AND DURING THE MORNING COMMUTE ON FRIDAY. COLD FRONT
APPROACHING FROM THE WEST WILL BRING A ROUND OF SHOWERS TO THE
REGION LATE FRIDAY MORNING THROUGH MID AFTERNOON. SHOULD BE A QUICK
HITTER WITH PRECIP PUSHING EAST OF THE FORECAST AREA BY MID
AFTERNOON.
WEAK HIGH PRESSURE BUILDING SOUTH OF NEW ENGLAND FRIDAY NIGHT SHOULD
RESULT IN MOSTLY CLEAR NIGHT WITH SEASONABLE TEMPS. HIGH PRESSURE
WILL QUICKLY SHIFT OFFSHORE SOUTH OF NEW ENGLAND SATURDAY MORNING.
EXPECT A MOSTLY SUNNY START TO THE DAY BEFORE CLOUDS AHEAD OF AN
APPROACHING COLD FRONT PUSH IN FROM THE WEST IN THE AFTERNOON. AT
THIS POINT IN TIME...APPEARS ANY ASSOCIATED PRECIP WILL HOLD OFF
UNTIL SATURDAY EVENING WITH A BRIEF SNOW SHOWER POSSIBLE WITH THE
FROPA. EXPECTING LITTLE IF ANY ACCUMULATION AS THIS MOISTURE
STARVED SYSTEM QUICKLY BLOWS THROUGH OVERNIGHT.
BEHIND THE FRONT ANOTHER SHOT OF ARCTIC AIR WILL INVADE NEW ENGLAND
FOR THE LAST HALF OF THE WEEKEND AND THE BEGINNING OF NEXT WEEK.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...VFR THIS MORNING GIVES WAY TO LIFR IN HEAVY SNOW THIS
AFTERNOON AND EVENING. MVFR TO VFR RETURNS AFTER MIDNIGHT TONIGHT.
HOWEVER...MVFR OF LOWER CONDITIONS ONCE AGAIN POSSIBLE IN SNOW
AND/OR RAIN WEDNESDAY...ESPECIALLY IN THE AFTERNOON AND EVENING.
LONG TERM...VFR THURSDAY. MVFR/IFR CEILINGS DEVELOPING THURSDAY
NIGHT AND PERSISTING THROUGH FRIDAY. VFR FRIDAY NIGHT THROUGH
SATURDAY.
&&
.MARINE...
SHORT TERM...GALES FOR THE OCEAN WATERS THIS AFTERNOON AND EVENING
AS LOW PRESSURE CRANKS UP IN THE GULF OF MAINE. SCA RETURNS LATER
TONIGHT AND FOR WEDNESDAY.
LONG TERM...SCA`S LIKELY WEDNESDAY NIGHT THROUGH EARLY THURSDAY.
GALES POSSIBLE ON FRIDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING FROM 10 AM THIS MORNING TO 4 AM EST
WEDNESDAY FOR MEZ018>020-023>026.
WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 AM EST
WEDNESDAY FOR MEZ012>014-021-022-027-028.
NH...WINTER STORM WARNING FROM 10 AM THIS MORNING TO 4 AM EST
WEDNESDAY FOR NHZ006-009.
WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 1 AM EST
WEDNESDAY FOR NHZ002>005-007-014.
WINTER STORM WARNING FROM 7 AM THIS MORNING TO 1 AM EST
WEDNESDAY FOR NHZ008-010-013.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 AM EST
WEDNESDAY FOR ANZ151-153.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 4 AM EST WEDNESDAY
FOR ANZ150-152-154.
&&
$$
NEAR/SHORT TERM...EKSTER
AREA FORECAST DISCUSSION
NWS GRAY ME
417 AM EST TUE FEB 18 2014
.SYNOPSIS...
LOW PRESSURE APPROACHING FROM THE WEST WILL REDEVELOP OFF THE NEW
ENGLAND COAST THIS AFTERNOON AND WILL RACE INTO THE MARITIMES THIS
EVENING. A COLD FRONT WILL SWING IN FROM THE WEST ON WEDNESDAY AND
LOW PRESSURE WILL DEVELOP ON THE FRONT AS IT PUSHES INTO THE GULF OF
MAINE WEDNESDAY EVENING. LOW PRESSURE WILL QUICKLY SHIFT EAST INTO
THE MARITIMES WEDNESDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE
WEST ON THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE REGION
THURSDAY NIGHT AND WILL BE QUICKLY FOLLOWED BY A COLD FRONT ON
FRIDAY. HIGH PRESSURE WILL BUILD SOUTH OF NEW ENGLAND FRIDAY NIGHT
AND WILL SHIFT OFFSHORE ON SATURDAY. A COLD FRONT FRONT WILL CROSS
THE REGION SATURDAY NIGHT.
&&
.NEAR TERM /TODAY THROUGH MIDNIGHT TONIGHT/...
A VERY STRONG SHORT WAVE TROUGH CROSSING THE LOWER GREAT LAKES
EARLY THIS MORNING WILL CONTINUE EASTWARD AND WILL AID IN RAPID
CYCLOGENESIS OVER SOUTHERN NEW ENGLAND BY THIS AFTERNOON. LIGHT
SNOW IS ALREADY OCCURRING IN THE WAA IN ADVANCE OF THIS SHORT WAVE
ACROSS NORTHEAST PA INTO CENTRAL NY. THIS ACTIVITY WILL LIKELY
PUSH INTO NORTHERN NEW ENGLAND LATER THIS MORNING BUT SHOULD
REMAIN LIGHT.
THE REAL SHOW LOOKS TO GET GOING LATE THIS MORNING AND EARLY
AFTERNOON AS LOW PRESSURE DEVELOP OVER LONG ISLAND NY OR SOUTHERN
NEW ENGLAND AS MID LEVEL LOW PRESSURE BEGINS TO CLOSE OFF. AS THIS
HAPPENS...STRONG DYNAMICS AND KINEMATICS WILL GO INTO MOTION AND
ALLOW A HEAVY PRECIPITATION SHIELD TO BLOSSOM OVER SOUTHERN NEW
ENGLAND AND HEAD NNEWD. THIS OCCURS AS STRONG ISENTROPIC LIFT
DEVELOPS VIA STRONG EASTERLY INFLOW UPGLIDING INTO A
STRENGTHENING DEFORMATION ZONE OVER NEW ENGLAND. THE RESULTANT
COMMA HEAD THAT DEVELOPS OVER SOUTHERN NEW ENGLAND SHOULD THEN
RIDE NNEWD INTO SOUTHERN NH AND SOUTHERNMOST ME BY EARLY
AFTERNOON...WHICH WILL THEN SPREAD NEWD FROM THERE...AFFECTING THE
REST OF THE WARNING AREA MAINLY LATE THIS AFTERNOON AND EVENING.
THE VARIOUS 00Z MODELS...INCLUDING LATEST RUNS OF THE RAP AND HRRR
ARE ALL IN GENERALLY GOOD AGREEMENT WITH THE DEVELOPING SYSTEM.
HOWEVER...THERE ARE STILL SOME DIFFERENCES IN HOW FAR WEST THE
HEAVIEST SNOW BANDING WILL EXTEND. THE CURRENT CONSENSUS IS FOR
THE AXIS OF MAX QPF AND RESULTANT SNOWFALL TO OCCUR ACROSS THE
SOUTHEASTERN QUARTER OF NEW HAMPSHIRE NORTHWARD TO THE COASTAL
PLAIN OF MAINE TO JUST SOUTH OF AUGUSTA. THE BANDING THEN WANES AS
THE SYSTEM STOPS DEEPENING...THEREFORE...LOWER AMOUNTS ARE
CURRENTLY EXPECTED NORTHEAST OF THE WARNING AREA. IT IS WORTH
NOTING AT THIS TIME THAT THE HIGHER RESOLUTION MODELS SUCH AS THE
RAP AND VARIOUS 4KM WRF MODELS ARE MORE POTENT...WITH MORE QPF
OVER A WIDER AREA. WHILE THEY ARE LIKELY SOMEWHAT OVERDONE...THIS
SITUATION MAY LEND MORE CREDENCE TO THEM AS THEY MAY BE CAPTURING
THE MESOSCALE PROCESSES BETTER THAN THE LOWER RESOLUTION MODELS.
THEREFORE...THE DAY SHIFT WILL HAVE TO ASSESS TRENDS AND SEE IF
WARNINGS AND ADVISORIES WILL HAVE TO BE ADJUSTED.
ON THE IMMEDIATE COAST...BOUNDARY LAYER TEMPERATURE ISSUES MAY
LEAD TO LOWER SNOWFALL AMOUNTS...HOWEVER...ONCE THE BANDING SETS
IN...SNOW SHOULD BE THE FAVORED PRECIP TYPE. THE SNOW MAY BE WET
THERE...SO SOME POWER OUTAGES POSSIBLE.
FORECAST STORM TOTAL SNOWFALL AMOUNTS ARE NOT EXPECTED TO BE
OVERLY HIGH WITH THIS SYSTEM...MAINLY IN THE 4-8 INCH RANGE WITH
LOCALLY HIGHER AMOUNTS POSSIBLE IN PERSISTENT BANDING.
HOWEVER...SNOWFALL RATES OF 1-3 INCHES PER HOUR FOR A
TIME...PROBABLY DURING THE EVENING COMMUTE WITH LIKELY ALLOW FOR A
HIGH-IMPACT EVENT. ISOLD THUNDER MAY EVEN OCCUR IN THE HEAVIEST
BANDING.
THE SNOW WILL TAPER OFF EARLY THIS MORNING ACROSS SOUTHERNMOST
ZONES...AND FINALLY END ON THE MID COAST AFTER MIDNIGHT.
&&
.SHORT TERM /MIDNIGHT TONIGHT THROUGH 6 PM WEDNESDAY/...
THE SNOW WILL TAPER OFF EARLY THIS MORNING ACROSS SOUTHERNMOST
ZONES...AND FINALLY END ON THE MID COAST AFTER MIDNIGHT.
NO REST FOR THE WEARY AS ANOTHER SYSTEM LOOKS TO AFFECT THE AREA
ON WEDNESDAY...MAINLY DURING THE AFTERNOON. THIS SYSTEM WILL BE
WEAKER AND BOUNDARY LAYER TEMPERATURES WARMER THAN TODAY/S SYSTEM.
HOWEVER...MODELS ARE SPINNING UP LOW PRESSURE CLOSE TO THE COAST
FASTER THAT PREVIOUS RUNS...ALLOWING FOR THE POTENTIAL FOR HEAVY
PRECIPITATION WED AFTERNOON AND EVENING. IF THIS
OCCURS...ESPECIALLY LIKELY ECMWF IS SHOWING...MORE WEATHER
HEADLINES MAY BE NEEDED...ESPECIALLY NORTHEAST OF PORTLAND TO THE
MID COAST.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
LOW PRESSURE WILL SPIN UP JUST OFFSHORE WEDNESDAY EVENING. IF
MODEL TRENDS CONTINUE LOW PRESSURE MAY SPIN UP QUICK ENOUGH TO
WARRANT ADVISORIES IN MID COAST MAINE AND FAR EASTERN COUNTIES OF
THE FORECAST AREA. QPF FROM THE NEW ECMWF HAS INCREASED
SIGNIFICANTLY FROM LAST NIGHT IN THESE AREAS.
IN ANY CASE...LOW PRESSURE WILL QUICKLY RACE INTO THE MARITIMES
BEFORE MIDNIGHT BRINGING A QUICK END TO PRECIP ACROSS THE AREA.
EXPECT CLEARING DOWNWIND OF THE MOUNTAINS AFTER MIDNIGHT BUT
INCREASING UPSLOPE FLOW AND LINGERING LOW LEVEL MOISTURE WILL KEEP
CLOUDS AND A CHANCE OF SNOW SHOWERS IN THE FORECAST FOR THE NORTH
INTO THURSDAY MORNING.
NARROW RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST ON THURSDAY
PROVIDING MOSTLY SUNNY SKIES FOR MOST OF THE AREA. EXPECT LINGERING
CLOUDS IN THE MOUNTAINS TO GRADUALLY DIMINISH DURING THE DAY. WILL
ACTUALLY SEE HIGHS CLIMBING ABOVE NORMAL WITH HIGHS REACHING THE MID
30S TO LOWER 40S NORTH AND LOWER TO MID 40S SOUTH.
HIGH PRESSURE WILL SHIFT OFFSHORE EARLY THURSDAY EVENING AND A WARM
FRONT WILL LIFT NORTH INTO THE REGION OVERNIGHT. THIS WILL SET THE
STAGE FOR ANOTHER ROUND OF MIXED PRECIPITATION IN SOUTHERN ZONES AND
SNOW CHANGING TO MIXED PRECIP IN NORTHERN ZONES BEFORE TAPERING OFF
TOWARD FRIDAY MORNING. QPF NOT VERY IMPRESSIVE WITH THIS INITIAL
BURST OF OVER-RUNNING PRECIP BUT WILL LIKELY CAUSE TRAVEL PROBLEMS
OVERNIGHT AND DURING THE MORNING COMMUTE ON FRIDAY. COLD FRONT
APPROACHING FROM THE WEST WILL BRING A ROUND OF SHOWERS TO THE
REGION LATE FRIDAY MORNING THROUGH MID AFTERNOON. SHOULD BE A QUICK
HITTER WITH PRECIP PUSHING EAST OF THE FORECAST AREA BY MID
AFTERNOON.
WEAK HIGH PRESSURE BUILDING SOUTH OF NEW ENGLAND FRIDAY NIGHT SHOULD
RESULT IN MOSTLY CLEAR NIGHT WITH SEASONABLE TEMPS. HIGH PRESSURE
WILL QUICKLY SHIFT OFFSHORE SOUTH OF NEW ENGLAND SATURDAY MORNING.
EXPECT A MOSTLY SUNNY START TO THE DAY BEFORE CLOUDS AHEAD OF AN
APPROACHING COLD FRONT PUSH IN FROM THE WEST IN THE AFTERNOON. AT
THIS POINT IN TIME...APPEARS ANY ASSOCIATED PRECIP WILL HOLD OFF
UNTIL SATURDAY EVENING WITH A BRIEF SNOW SHOWER POSSIBLE WITH THE
FROPA. EXPECTING LITTLE IF ANY ACCUMULATION AS THIS MOISTURE
STARVED SYSTEM QUICKLY BLOWS THROUGH OVERNIGHT.
BEHIND THE FRONT ANOTHER SHOT OF ARCTIC AIR WILL INVADE NEW ENGLAND
FOR THE LAST HALF OF THE WEEKEND AND THE BEGINNING OF NEXT WEEK.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SHORT TERM...VFR THIS MORNING GIVES WAY TO LIFR IN HEAVY SNOW THIS
AFTERNOON AND EVENING. MVFR TO VFR RETURNS AFTER MIDNIGHT TONIGHT.
HOWEVER...MVFR OF LOWER CONDITIONS ONCE AGAIN POSSIBLE IN SNOW
AND/OR RAIN WEDNESDAY...ESPECIALLY IN THE AFTERNOON AND EVENING.
LONG TERM...VFR THURSDAY. MVFR/IFR CEILINGS DEVELOPING THURSDAY
NIGHT AND PERSISTING THROUGH FRIDAY. VFR FRIDAY NIGHT THROUGH
SATURDAY.
&&
.MARINE...
SHORT TERM...GALES FOR THE OCEAN WATERS THIS AFTERNOON AND EVENING
AS LOW PRESSURE CRANKS UP IN THE GULF OF MAINE. SCA RETURNS LATER
TONIGHT AND FOR WEDNESDAY.
LONG TERM...SCA`S LIKELY WEDNESDAY NIGHT THROUGH EARLY THURSDAY.
GALES POSSIBLE ON FRIDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING FROM 10 AM THIS MORNING TO 4 AM EST
WEDNESDAY FOR MEZ018>020-023>026.
WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 AM EST
WEDNESDAY FOR MEZ012>014-021-022-027-028.
NH...WINTER STORM WARNING FROM 10 AM THIS MORNING TO 4 AM EST
WEDNESDAY FOR NHZ006-009.
WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 1 AM EST
WEDNESDAY FOR NHZ002>005-007-014.
WINTER STORM WARNING FROM 7 AM THIS MORNING TO 1 AM EST
WEDNESDAY FOR NHZ008-010-013.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 AM EST
WEDNESDAY FOR ANZ151-153.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 4 AM EST WEDNESDAY
FOR ANZ150-152-154.
&&
$$
NEAR/SHORT TERM...EKSTER
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
456 AM EST TUE FEB 18 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION TODAY...FOLLOWED BY A COLD
FRONT MOVING THROUGH THE AREA WEDNESDAY. HIGH PRESSURE WILL RETURN
THURSDAY AND THURSDAY NIGHT BEFORE A STRONG COLD FRONT PASSES
FRIDAY. HIGH PRESSURE WILL THEN BRIEFLY RETURN THROUGH
SATURDAY...FOLLOWED BY UNSETTLED WEATHER ON SUNDAY AND MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...ALL PCPN E OF I-95. HV CANX REST OF WINTER WX ADVY.
ALSO...HV NOTED PCPN DVLP SE OF SNOW BAND ACRS SRN MD. RDR AND
MTRS SUGGEST THIS TO BE SOMETHING OTR THAN SNW. RAP MDL SNDGS
SUPPORT MOST OBS SUGGESTING SLEET...HWVR SOME PCPN SCHEMES SUGGEST
SOME FZRA TOO. HV ADDED A MIX TO GRIDS AND ISSUED SPS. REGARDLESS
OF TYPE...IT/LL BE DONE ACRS MUCH OF THE AREA BY 6AM.
PRVS DSCN...
WATER VAPOR IMGRY AND SFC ANALYSIS SUGGESTS THAT LOPRES OVER THE
ERN GRTLKS...PROGGED TO HEAD TWD THE ST LAWR VLY. THIS RTE IS
FURTHER N THAT PRVS PROGS...AND KEEP ENERGY TOO FAR AWAY FM CWFA
TO SUPPORT APPRECIATIVE PCPN. CSTL RDVLPMNT LOOKING TO TAKE PLACE
OFF LONG ISLAND OR SNE...WHICH IS ALSO TOO FAR N FOR US. WITH THAT
IN MIND... HV LWRD QPF BY ABT HALF...WHICH SUBSEQUENTLY LWRD SNW
ACCUMS. AS A RESULT...HV CANX WINTER WX ADVY FOR MUCH OF THE AREA.
AM HANGING ONTO NE MD /FREDERICK TO HARFORD/BALT CITY/ AS AREA
POSITIONED FOR BEST SUPPORT AND HV SNOW HEADED THAT WAY.
ELSW...PCPN STILL LKLY... BUT ACCUMS MINIMAL. AM KEEPING IT MAINLY
SNOW FOR SIMPLICITY...BUT ACKNOWLEDGE THAT THERE WL BE A RA/SN
LINE ACRS SRN MD. CHC FOR MIXED PCPN MINIMAL.
ANY LINGERING PCPN SHUD BE PULLING E OF THE AREA BY 12Z...W/ RAPID
CLRG MVG IN BHD IT. THE PD OF POTL UPSLP SEEM MINIMAL AS WNDS DONT
VEER MUCH MORE THAN WLY /AND THE LAKES FRZN ANYWAYS/. CAA BHD TROF
DOES KICK UP MOMENTUM TRANSFER...AND HV G20 KT IN THE AFTN /G30 KT
IN THE APLCNS/.
WLY WNDS BHD TROF AXIS WL SUPPORT A WARMING TREND...AND FLLWD MOS
MEAN FOR MAXT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
ZNL FLOW WL BE IN PLACE TNGT-TMRW...W/ BRIEF SFC RDGG. A NRN STREAM
S/WV WL DROP A WK CDFNT ACRS THE AREA WED...MOST LKLY LT MRNG. WL BE
INCRSG CLDS ELY MRNG...AND INTRODUCING CHC RA INTO THE FCST. ALTHO
TEMPS TNGT WL BE MOSTLY SUBFRZG...SWLY FLOW/WAA WL BE SUFFICIENT TO
BRING TEMPS ABV BEFORE PCPN STARTS. AGN...GOOD MIXING WL FLLW FNT...
PROVIDING A BRZY AFTN. THE COMPRESSIONAL WARMING SHUD OFFSET ANY
CAA...AND HV TEMPS WED HIER THAN TUE-- BTWN MET/MAV MOS BUT TWD THE
WARMER EDGE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE MOVES OVERHEAD ON WED NIGHT...THEN OFF THE NC COAST ON
THURSDAY WHICH WILL BRING SOME NICE WARM GULF OF MX FLOW INTO
REGION. ACTUALLY...TEMPS ARE PROGGED BY THE MEX IN THE LOWER 50S
WHICH IS ONLY A FEW DEG ABOVE NORMAL FOR THIS TIME OF FEB...BUT
WILL SEEM LIKE SPRING WITH THE COLD WX SO FAR THIS MONTH. FRI SHOULD/COULD
BE EVEN WARMER AHEAD OF THE FRONT FOR A TIME DESPITE
CLOUDS. THE TIMING...CLOUD COVER...AND SHOWERS CONTRIBUTE TO MUCH
UNCERTAINTY ABOUT HOW HIGH WE GET ON FRI.
FRIDAY ALSO HAS THE MAKING OF AN INTERESTING DAY WITH SVR
POTENTIAL ASSOC WITH THE STRONG FROPA. YESTERDAY...SPC HAD REGION
IN DAY 5 OUTLOOK. HARD TO THINK ABOUT SVR WITH A SNOWPACK IN PLACE
BUT H85 JET OF 70+KTS IS PRESENT IN CONDITIONALLY UNSTABLE ATMOS PER
00Z GFS MODEL SOUNDINGS. SEVERE POTL WILL DEPEND GREATLY ON THE
TIMING OF THE FRONT...WITH THE GFS BEING QUICKER WITH PREDAWN
FROPA FRIDAY MORNING...AND THE ECMWF TRAILING BY 6-12 HOURS LATER
WHICH WOULD PRODUCE MORE OF A SVR POTENTIAL.
AFTER FROPA FRI...HIGH PRESSURE BUILDS IN AGAIN THROUGH SAT. 00Z
ECMWF HAVE A CLIPPER LOW MOVING FROM THE OH VALLEY TO THE NORTHEAST
US...JUST CATCHING THE CWA ON THE SOUTHERN PCPN GRADIENT.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
FLGT CATEGORIES HV BEEN VARIABLE IN REPONSE TO AREAS OF SNW.
HWVR...MOST OF THOSE CHGS HV ALREADY HPPND. STILL MVFR TO PERHAPS
BRIEF IFR PSBL FOR METRO TERMINALS THRU 11Z. /MOST OF THE
RESTRICTIONS HV ALREADY TAKEN PLACE AT MRB./ AFTER THAT...CONDS
SHUD IMPRV TO VFR...AND REMAIN THERE THRU TNGT.
A CDFNT WL APPROACH TERMINALS WED MRNG...AND MVFR CONDS SHUD RTN
THEN. VFR FROM WED NIGHT THROUGH THU NIGHT...BUT MVFR RETURNS ON
FRI WITH POTL TSTMS AND LLWS WITH STRONG LLVL JET OF 60-70KTS.
&&
.MARINE...
SELY WNDS HV SUBSIDED ACRS MARINE AREA. SCA HAS BEEN CANCELLED FOR
THE MRNG. HWVR...WLY WNDS WL INCR ONCE AGN BHD TROF AXIS LATER
TDA. SCA IN EFFECT FOR ALL WATERS 11AM-5PM. A BRIEF PD OF RDGG
TNGT WL SUPPORT DIMINISHING WNDS. THEN...ANTHR WK CDFNT WL DROP
ACRS WATERS WED MIDDAY. MOMENTUM TRANSFER BHD THIS CDFNT
SUFFICIENT TO CAUSE A RTN TO SCA FOR WED AFTN AS WELL.
MARINE WINDS BLO SCA UNTIL THURSDAY AFTERNOON...WHEN SCA IS
LIKELY. BOTH THE 00Z GFS AND ECMWF HAVE STRONG LLVL WIND
FIELDS THURSDAY NIGHT AND FRI...BUT WITH WARM AIR OVER COLDER
WATERS. HOWEVER...HAVE RAISED THE POTL OF GLW FOR FRIDAY FOR NOW.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 5 PM EST THIS
AFTERNOON FOR ANZ530>543.
SMALL CRAFT ADVISORY FROM NOON TO 6 PM EST WEDNESDAY FOR
ANZ530>543.
&&
$$
SYNOPSIS...LEE
NEAR TERM...HTS
SHORT TERM...HTS
LONG TERM...LEE
AVIATION...LEE/HTS
MARINE...LEE/HTS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
943 PM EST WED FEB 19 2014
.UPDATE...
ISSUED AT 942 PM EST WED FEB 19 2014
ADJUSTED MIN TEMPS UP A COUPLE OF DEGREES...MAINLY OVER THE W AND
NEAR THE WI BORDER WHERE HI CLDS HAVE ARRIVED BEFORE SFC WINDS COULD
DECOUPLE. BUT CONCERN THAT HI CLDS MIGHT THIN LATER TNGT WITH
RELATIVELY LGT WINDS/OVERALL DRY AIRMASS IN PLACE LIMITED THE
ADJUSTMENT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 518 PM EST WED FEB 19 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW TROF MOVING ACROSS THE
ROCKIES WITH 2 MAIN SHORTWAVES OF INTEREST THAT WILL CONSPIRE TO
BRING A STRONG WINTER STORM TO THE UPPER LAKES. ONE IS OVER SRN
SASKATCHEWAN/MT AND THE OTHER IS MOVING ACROSS NV/UT. WELL OUT AHEAD
OF THESE FEATURES...A QUIET NIGHT IS EXPECTED ACROSS THE FCST AREA.
MAINLY CLEAR SKIES INITIALLY WILL GIVE WAY TO INCREASING HIGH AND
MID CLOUDS DURING THE NIGHT. LIGHT WINDS AND LACK OF SIGNIFICANT
CLOUD COVER EARLY SHOULD ALLOW TEMPS OVER THE CNTRL AND E TO FALL
QUICKLY. LEANED TOWARD SOME OF THE COLDER GUIDANCE WITH MINS IN THE
MID TEENS IN THE INTERIOR. OUT W...DEVELOPING LIGHT SOUTHERLY FLOW
AND A QUICKER INCREASE IN CLOUDS SHOULD HOLD TEMPS UP INTO THE
LOW/MID 20S.
ON THU...LOW PRES ORGANIZING OVER THE SRN PLAINS EARLY IN THE MORNING
WILL LIFT NE INTO THE MID MISSISSIPPI VALLEY DURING THE AFTN.
GENERAL MODEL TREND IN THE LAST DAY OR SO HAS BEEN FOR A SLOWER
EXPANSION OF PCPN NE INTO THE UPPER LAKES AS SYSTEM IS TENDING TO
START THE RAPID DEEPENING PHASE MORE QUICKLY BEFORE REACHING THE
UPPER LAKES. OPTED TO FOLLOW THIS TREND AND FAVOR THE SLOWER
SOLUTIONS. AS A RESULT...PCPN ONSET HAS BEEN PUSHED BACK SOME. MAIN
PUSH OF HEAVY PCPN IS NOT EXPECTED UNTIL THU NIGHT WHEN IT WILL
RAPIDLY SPREAD ACROSS THE AREA. INITIALLY...EVAPORATIVE/ADIABATIC
COOLING SHOULD LEAD TO PTYPE AS MAINLY SNOW...BUT DID INCLUDE SOME
MENTION OF MIXED PTYPES OVER ABOUT THE SE HALF.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 518 PM EST WED FEB 19 2014
MAIN CONCERN FOR THE LONG TERM FORECAST IS THE WINTER STORM EXPECTED
ON THURSDAY NIGHT AND FRIDAY.
EARLIER MODEL RUNS HAVE CONSISTENTLY KEPT THE TWO SURFACE LOWS
CROSSING FROM ILLINOIS AND MINNESOTA THURSDAY AFTERNOON TO A MERGED
LOW OVER CENTRAL UPPER MICHIGAN BY LATE THURSDAY EVENING. THIS
BRINGS WARM AIR AND HENCE MIXED PRECIPITATION INTO PORTIONS OF
CENTRAL AND EASTERN UPPER MICHIGAN. CONCERNS THIS PAST FEW DAYS HAVE
BEEN ABOUT THE FORECASTED LOW TRACK SHIFTING AS THE MODELS HAD NOT
REALLY BEEN ABLE TO ADEQUATELY SAMPLE THE SYSTEM UP UNTIL TODAY.
HOWEVER...NOW THAT THE LOW PRESSURE TROUGH RESPONSIBLE FOR THE
DEVELOPMENT OF THIS SYSTEM HAS MOVED ONSHORE IN THE PACIFIC
NORTHWEST...DIFFERENCES IN THE MODELS HAVE DEVELOPED. THE 6Z NAM
BEGAN TRENDING THE SYSTEM EASTWARD...AND THE 12Z NAM HAS COMPLETELY
MOVED THE LOW PRESSURE CENTER LATE THURSDAY EVENING FROM THE CENTRAL
U.P. TO OVER NORTHERN LAKE MICHIGAN. IT IS ALSO SLOWER THAN THE
OTHER SOLUTIONS. FURTHER COMPLICATING MATTERS...THE 12Z GEM MOVED
THE LOW PRESSURE CENTER FURTHER WEST OVER NORTH CENTRAL UPPER
MICHIGAN. THE 12Z GFS HOWEVER...HAS TRENDED SLIGHTLY WESTWARD FROM
ITS 6Z SOLUTION. THIS PUTS THE LOW OVER WESTERN UPPER MI BY 6Z
FRIDAY.
OVERALL...FURTHER EAST SOLUTIONS DIMINISH MIXED PRECIPITATION
CONCERNS AND PULL THE HEAVIEST CORE OF SNOW FURTHER EAST...WHEREAS
PREVIOUS FCST HAD IT MAINLY OVER THE WEST. FOR THIS
FORECAST...DECIDED TO LEAN TOWARDS THE WESTERN SOLUTIONS AS THIS HAS
BEEN THE MORE PERSISTENT SOLUTION. STARTED TRENDING SLIGHTLY MORE
WESTWARD WITH THE FORECAST GRIDS AS A RESULT...NAMELY THE
GFS/GEM/ECMWF COMPROMISE. AS FAR AS TIMING GOES...THE GEM BRINGS
THINGS IN SLOWER. THE 00Z ECMWF/12Z GFS BRING THE LOW THROUGH
QUICKER BY ABOUT 6 HRS...WITH THE CENTER OVER NORTH CENTRAL UPPER MI
BY 6Z FRIDAY. THE GEM IS STILL OVER CENTRAL WI AT THIS TIME.
PREVIOUS RUNS OF THE GEM HAD TIMING MORE LIKE THAT OF THE RECENT
RUNS OF THE ECMWF/GFS...THOUGH THE GFS TENDS TO BE MORE PROGRESSIVE
WITH SYSTEMS. WILL GO MIDDLE OF THE ROAD FOR NOW TO COMPENSATE FOR
THIS.
THE GFS/GEM/ECMWF BLEND SHOWS A BROAD AREA OF ISENTROPIC ASCENT
OVERSPREADING THE AREA STARTING THURSDAY AFTERNOON...WITH THE
STRONGEST MOISTURE TRANSPORT FROM THE 18Z THUR-06Z FRI TIME FRAME
OVER LOWER MICHIGAN...NORTHERN WI...AND CENTRAL/EASTERN UPPER
MICHIGAN. 700/850MB FGEN BAND MOVES FROM ROUGHLY SOUTH TO NORTH
ACROSS THE AREA BEGINNING AROUND THIS TIME AND CONTINUING THROUGH AS
SYSTEM DEEPENS WITH NEGATIVELY TILTING UPPER TROUGH. THE SYSTEM
BEGINS TO OCCLUDE...AND THE TROWAL DEVELOPS AND POSITIONS ITSELF/AND
THE ASSOCIATED FGEN BAND OVER WESTERN UPPER MI.
AS FAR AS PTYPE GOES...THERE ARE DIFFERENCES BETWEEN THE 12Z GFS/12Z
GEM/00Z ECMWF WITH REGARDS TO THE HEIGHT/TEMP OF THE WARMEST LAYER
ALOFT AND DEPTH OF THE SURFACE COLD LAYER FROM 00-03Z FRI...AND THE
SURFACE WARM LAYER AROUND 6-9Z FRI. BY 12Z FRIDAY THE MODELS ARE
CONSISTENT IN HAVING THE WHOLE SOUNDING BELOW ZERO.
IT LOOKS LIKE THE EASTERN HALF WILL SEE THE BEST SHOT FOR FREEZING
RAIN FROM 00-9Z...AND THE RAIN/SNOW LINE SEEMS TO SET UP FROM
EASTERN MARQUETTE COUNTY TO EASTERN DICKINSON COUNTY. ONCE WE GET
PAST 9Z...THE ENTIRE PROFILE IN THIS AREA DROPS BELOW ZERO.
GENERALLY...MIXED PRECIP TIME LOOKS TO BE QUICK ESPECIALLY GIVEN THE
STRONG DYNAMICS IN THE SYSTEM. MAX TS ALOFT REACH A MAX OF 2C WITH
THE WARM GFS...AND STAY BELOW ZERO WITH THE 00Z ECMWF. EAST OF THIS
LINE...WARM LAYER REACHES 3C AROUND 850 AND THE COLD SURFACE LAYER
IS FAIRLY SHALLOW AND EVEN SNEAKS ABOVE ZERO FROM 6-9Z ACCORDING TO
THE GEM...BRINGING A POT POURRI OF PRECIPITATION. THIS AREA IS STILL
ON TRACK FOR SEEING MORE ICE ACCUMULATION. ALL OTHER AREAS WILL BE
PRIMARILY SNOW.
WINDS ARE A CONSIDERABLE ISSUE WITH THIS SYSTEM AS WELL. STRONG
PRESSURE RISE FALL COUPLET SNEAKS IN WITH THE SYSTEM...BRINGING A
SIGNIFICANT ISALLOBARIC COMPONENT TO THE WIND. THIS IS ESPECIALLY
THE CASE ACROSS EASTERN UPPER MICHIGAN EARLY THURSDAY EVENING UNTIL
AROUND 06Z...AND THEN IN THE WEST AND NORTH CENTRAL BY FRIDAY
MORNING/AFTERNOON. THIS WILL ONLY ADD TO THE REDUCED VISIBILITY WITH
EXTENSIVE BLOWING/DRIFTING SNOW. GUSTS IN SOME OF THESE
AREAS...PARTICULARLY THE EXPOSED REGIONS IN THE WEST-NORTHWEST
FAVORED REGIONS...WILL LIKELY SEE GUSTS INTO THE 40S FRIDAY.
GIVEN THE RECENT MODEL RUNS...FELT CONFIDENT ENOUGH TO GO WITH A
WINTER STORM WARNING FOR LOCATIONS WEST OF MARQUETTE/DICKINSON
COUNTIES. SNOW ACCUMULATIONS RANGE FROM ABOUT 8 TO 12 INCHES IN
THESE COUNTIES. ALSO UPGRADED THE BLIZZARD WATCH TO A WARNING FOR
KEWEENAW/N.HOUGHTON COUNTIES GIVEN THE EXTENSIVE WINDS AND SNOW.
OTHERWISE...KEPT THE REST OF THE CWA UNDER A WINTER STORM WATCH TO
PIN DOWN THE DETAILS. IF THE SYSTEM DOES SNEAK EASTWARD...WE MAY
NEED TO ADD ADDITIONAL COUNTIES INTO THE WARNING. MOST OF THE
UNCERTAINTIES WILL IMPACT THE CENTRAL/EASTERN COUNTIES THE MOST...SO
A WATCH SEEMED BEST RIGHT NOW.
FOR THE EXTENDED...WITH THE LINGERING UPPER LEVEL TROUGH IN THE
AREA...EXPECT COLDER TEMPERATURES TO RETURN. 850MB TEMPS WILL DROP
TOWARDS -25C TO -30C AS WE HEAD FURTHER INTO THE LATER TIME PERIODS.
SNOW WILL GRADUALLY CONFINE TO THE WEST WIND FAVORED REGIONS NEAR
LAKE SUPERIOR...AS ICE WILL LIKELY BE BROKEN ENOUGH TO INDUCE
INSTABILITY FOR LES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 653 PM EST WED FEB 19 2014
EXPECT VFR CONDITIONS TO PREVAIL AT ALL 3 TAF SITES THRU AT LEAST
THIS EVNG. BUT THE ARRIVAL OF MORE LLVL MSTR LATE TNGT IN THE PRESENCE
OF NOCTURNAL COOLING MIGHT RESULT IN SOME FOG AND LO CLD DEVELOPMENT...
ESPECIALLY AT SAW WITH MORE FVRBL UPSLOPE SSE WIND DIRECTION. BUT
INCRSG MID/HI CLDS WL LIMIT RADIATIONAL COOLING AND THE POTENTIAL FOR
IFR VSBYS/CIGS. AS DEEPENING LO PRES APRCHS UPR MI FM THE S ON THU...
EXPECT DETERIORATING CONDITIONS WITH GUSTY WINDS/SOME LGT SN AND
BLSN/MVFR CONDITIONS ARRIVING IN THE AFTN. AN EXTENDED PERIOD OF
CONDITIONS BLO AIRFIELD LANDING MINS IS POSSIBLE AT KCMX BEGINNING AT
SOME POINT THU NIGHT OR FRI MORNING AS THE MORE EXPOSED KEWEENAW
PENINSULA WL BE PLAGUED BY VERY STRONG E WINDS SHIFTING TO THE W AND
SN/BLSN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 PM EST WED FEB 19 2014
WINDS WILL DIMINISH THIS EVENING...BECOMING LIGHT UNDER 15KT. WINDS
WILL THEN BEGIN TO INCREASE OVERNIGHT AHEAD OF A WINTER STORM
ORGANIZING OVER THE SOUTHERN PLAINS. E TO NE WINDS MAY REACH UPWARDS
OF 30KT OVER FAR WRN LAKE SUPERIOR BY MORNING. WINDS WILL STEADILY
INCREASE ACROSS THE LAKE THU AS THE ORGANIZING LOW PRES SYSTEM LIFTS
INTO THE MID MISSISSIPPI VALLEY. THE LOW WILL THEN RAPIDLY DEEPEN...
BECOMING AN INTENSE LOW WITH PRES BOTTOMING OUT AROUND 28.7 INCHES
AS IT MOVES NNE ACROSS CNTRL UPPER MI AND CNTRL LAKE SUPERIOR LATE
THU NIGHT AND FRI MORNING. AHEAD OF THE LOW...EASTERLY GALES WILL
DEVELOP OVER CNTRL AND ERN LAKE SUPERIOR THU EVENING. WHILE E TO NE
GALES MAY ALSO DEVELOP OVER WRN LAKE SUPERIOR...W GALES ARE MORE
LIKELY IN THE WAKE OF THE LOW FRI/FRI NIGHT. GALES WILL CONTINUE
OVER CNTRL AND ERN LAKE SUPERIOR FRI THRU SAT WITH THE POTENTIAL FOR
STORM FORCE WINDS OVER ERN LAKE SUPERIOR FRI. ALTHOUGH GALES WILL
END BY SUN...WINDS WILL LIKELY REMAIN IN THE 20-30KT RANGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING FROM 4 PM EST /3 PM CST/ THURSDAY TO NOON
EST /11 AM CST/ FRIDAY FOR MIZ002-004-009-010-084.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ006-007-012>014-085.
BLIZZARD WARNING FROM 7 PM THURSDAY TO 10 PM EST FRIDAY FOR
MIZ001-003.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ005-011.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THURSDAY TO 6 PM EST SATURDAY FOR LSZ244-
245-264>267.
GALE WARNING FROM 7 AM EST /6 AM CST/ FRIDAY TO 7 AM EST /6 AM
CST/ SATURDAY FOR LSZ162-241>243-263.
LAKE MICHIGAN...
GALE WARNING FROM 7 PM THURSDAY TO 5 PM EST FRIDAY FOR LMZ221-
248-250.
&&
$$
UPDATE...KC
SHORT TERM...ROLFSON
LONG TERM...MCD
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
656 PM EST WED FEB 19 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 518 PM EST WED FEB 19 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW TROF MOVING ACROSS THE
ROCKIES WITH 2 MAIN SHORTWAVES OF INTEREST THAT WILL CONSPIRE TO
BRING A STRONG WINTER STORM TO THE UPPER LAKES. ONE IS OVER SRN
SASKATCHEWAN/MT AND THE OTHER IS MOVING ACROSS NV/UT. WELL OUT AHEAD
OF THESE FEATURES...A QUIET NIGHT IS EXPECTED ACROSS THE FCST AREA.
MAINLY CLEAR SKIES INITIALLY WILL GIVE WAY TO INCREASING HIGH AND
MID CLOUDS DURING THE NIGHT. LIGHT WINDS AND LACK OF SIGNIFICANT
CLOUD COVER EARLY SHOULD ALLOW TEMPS OVER THE CNTRL AND E TO FALL
QUICKLY. LEANED TOWARD SOME OF THE COLDER GUIDANCE WITH MINS IN THE
MID TEENS IN THE INTERIOR. OUT W...DEVELOPING LIGHT SOUTHERLY FLOW
AND A QUICKER INCREASE IN CLOUDS SHOULD HOLD TEMPS UP INTO THE
LOW/MID 20S.
ON THU...LOW PRES ORGANIZING OVER THE SRN PLAINS EARLY IN THE MORNING
WILL LIFT NE INTO THE MID MISSISSIPPI VALLEY DURING THE AFTN.
GENERAL MODEL TREND IN THE LAST DAY OR SO HAS BEEN FOR A SLOWER
EXPANSION OF PCPN NE INTO THE UPPER LAKES AS SYSTEM IS TENDING TO
START THE RAPID DEEPENING PHASE MORE QUICKLY BEFORE REACHING THE
UPPER LAKES. OPTED TO FOLLOW THIS TREND AND FAVOR THE SLOWER
SOLUTIONS. AS A RESULT...PCPN ONSET HAS BEEN PUSHED BACK SOME. MAIN
PUSH OF HEAVY PCPN IS NOT EXPECTED UNTIL THU NIGHT WHEN IT WILL
RAPIDLY SPREAD ACROSS THE AREA. INITIALLY...EVAPORATIVE/ADIABATIC
COOLING SHOULD LEAD TO PTYPE AS MAINLY SNOW...BUT DID INCLUDE SOME
MENTION OF MIXED PTYPES OVER ABOUT THE SE HALF.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 518 PM EST WED FEB 19 2014
MAIN CONCERN FOR THE LONG TERM FORECAST IS THE WINTER STORM EXPECTED
ON THURSDAY NIGHT AND FRIDAY.
EARLIER MODEL RUNS HAVE CONSISTENTLY KEPT THE TWO SURFACE LOWS
CROSSING FROM ILLINOIS AND MINNESOTA THURSDAY AFTERNOON TO A MERGED
LOW OVER CENTRAL UPPER MICHIGAN BY LATE THURSDAY EVENING. THIS
BRINGS WARM AIR AND HENCE MIXED PRECIPITATION INTO PORTIONS OF
CENTRAL AND EASTERN UPPER MICHIGAN. CONCERNS THIS PAST FEW DAYS HAVE
BEEN ABOUT THE FORECASTED LOW TRACK SHIFTING AS THE MODELS HAD NOT
REALLY BEEN ABLE TO ADEQUATELY SAMPLE THE SYSTEM UP UNTIL TODAY.
HOWEVER...NOW THAT THE LOW PRESSURE TROUGH RESPONSIBLE FOR THE
DEVELOPMENT OF THIS SYSTEM HAS MOVED ONSHORE IN THE PACIFIC
NORTHWEST...DIFFERENCES IN THE MODELS HAVE DEVELOPED. THE 6Z NAM
BEGAN TRENDING THE SYSTEM EASTWARD...AND THE 12Z NAM HAS COMPLETELY
MOVED THE LOW PRESSURE CENTER LATE THURSDAY EVENING FROM THE CENTRAL
U.P. TO OVER NORTHERN LAKE MICHIGAN. IT IS ALSO SLOWER THAN THE
OTHER SOLUTIONS. FURTHER COMPLICATING MATTERS...THE 12Z GEM MOVED
THE LOW PRESSURE CENTER FURTHER WEST OVER NORTH CENTRAL UPPER
MICHIGAN. THE 12Z GFS HOWEVER...HAS TRENDED SLIGHTLY WESTWARD FROM
ITS 6Z SOLUTION. THIS PUTS THE LOW OVER WESTERN UPPER MI BY 6Z
FRIDAY.
OVERALL...FURTHER EAST SOLUTIONS DIMINISH MIXED PRECIPITATION
CONCERNS AND PULL THE HEAVIEST CORE OF SNOW FURTHER EAST...WHEREAS
PREVIOUS FCST HAD IT MAINLY OVER THE WEST. FOR THIS
FORECAST...DECIDED TO LEAN TOWARDS THE WESTERN SOLUTIONS AS THIS HAS
BEEN THE MORE PERSISTENT SOLUTION. STARTED TRENDING SLIGHTLY MORE
WESTWARD WITH THE FORECAST GRIDS AS A RESULT...NAMELY THE
GFS/GEM/ECMWF COMPROMISE. AS FAR AS TIMING GOES...THE GEM BRINGS
THINGS IN SLOWER. THE 00Z ECMWF/12Z GFS BRING THE LOW THROUGH
QUICKER BY ABOUT 6 HRS...WITH THE CENTER OVER NORTH CENTRAL UPPER MI
BY 6Z FRIDAY. THE GEM IS STILL OVER CENTRAL WI AT THIS TIME.
PREVIOUS RUNS OF THE GEM HAD TIMING MORE LIKE THAT OF THE RECENT
RUNS OF THE ECMWF/GFS...THOUGH THE GFS TENDS TO BE MORE PROGRESSIVE
WITH SYSTEMS. WILL GO MIDDLE OF THE ROAD FOR NOW TO COMPENSATE FOR
THIS.
THE GFS/GEM/ECMWF BLEND SHOWS A BROAD AREA OF ISENTROPIC ASCENT
OVERSPREADING THE AREA STARTING THURSDAY AFTERNOON...WITH THE
STRONGEST MOISTURE TRANSPORT FROM THE 18Z THUR-06Z FRI TIME FRAME
OVER LOWER MICHIGAN...NORTHERN WI...AND CENTRAL/EASTERN UPPER
MICHIGAN. 700/850MB FGEN BAND MOVES FROM ROUGHLY SOUTH TO NORTH
ACROSS THE AREA BEGINNING AROUND THIS TIME AND CONTINUING THROUGH AS
SYSTEM DEEPENS WITH NEGATIVELY TILTING UPPER TROUGH. THE SYSTEM
BEGINS TO OCCLUDE...AND THE TROWAL DEVELOPS AND POSITIONS ITSELF/AND
THE ASSOCIATED FGEN BAND OVER WESTERN UPPER MI.
AS FAR AS PTYPE GOES...THERE ARE DIFFERENCES BETWEEN THE 12Z GFS/12Z
GEM/00Z ECMWF WITH REGARDS TO THE HEIGHT/TEMP OF THE WARMEST LAYER
ALOFT AND DEPTH OF THE SURFACE COLD LAYER FROM 00-03Z FRI...AND THE
SURFACE WARM LAYER AROUND 6-9Z FRI. BY 12Z FRIDAY THE MODELS ARE
CONSISTENT IN HAVING THE WHOLE SOUNDING BELOW ZERO.
IT LOOKS LIKE THE EASTERN HALF WILL SEE THE BEST SHOT FOR FREEZING
RAIN FROM 00-9Z...AND THE RAIN/SNOW LINE SEEMS TO SET UP FROM
EASTERN MARQUETTE COUNTY TO EASTERN DICKINSON COUNTY. ONCE WE GET
PAST 9Z...THE ENTIRE PROFILE IN THIS AREA DROPS BELOW ZERO.
GENERALLY...MIXED PRECIP TIME LOOKS TO BE QUICK ESPECIALLY GIVEN THE
STRONG DYNAMICS IN THE SYSTEM. MAX TS ALOFT REACH A MAX OF 2C WITH
THE WARM GFS...AND STAY BELOW ZERO WITH THE 00Z ECMWF. EAST OF THIS
LINE...WARM LAYER REACHES 3C AROUND 850 AND THE COLD SURFACE LAYER
IS FAIRLY SHALLOW AND EVEN SNEAKS ABOVE ZERO FROM 6-9Z ACCORDING TO
THE GEM...BRINGING A POT POURRI OF PRECIPITATION. THIS AREA IS STILL
ON TRACK FOR SEEING MORE ICE ACCUMULATION. ALL OTHER AREAS WILL BE
PRIMARILY SNOW.
WINDS ARE A CONSIDERABLE ISSUE WITH THIS SYSTEM AS WELL. STRONG
PRESSURE RISE FALL COUPLET SNEAKS IN WITH THE SYSTEM...BRINGING A
SIGNIFICANT ISALLOBARIC COMPONENT TO THE WIND. THIS IS ESPECIALLY
THE CASE ACROSS EASTERN UPPER MICHIGAN EARLY THURSDAY EVENING UNTIL
AROUND 06Z...AND THEN IN THE WEST AND NORTH CENTRAL BY FRIDAY
MORNING/AFTERNOON. THIS WILL ONLY ADD TO THE REDUCED VISIBILITY WITH
EXTENSIVE BLOWING/DRIFTING SNOW. GUSTS IN SOME OF THESE
AREAS...PARTICULARLY THE EXPOSED REGIONS IN THE WEST-NORTHWEST
FAVORED REGIONS...WILL LIKELY SEE GUSTS INTO THE 40S FRIDAY.
GIVEN THE RECENT MODEL RUNS...FELT CONFIDENT ENOUGH TO GO WITH A
WINTER STORM WARNING FOR LOCATIONS WEST OF MARQUETTE/DICKINSON
COUNTIES. SNOW ACCUMULATIONS RANGE FROM ABOUT 8 TO 12 INCHES IN
THESE COUNTIES. ALSO UPGRADED THE BLIZZARD WATCH TO A WARNING FOR
KEWEENAW/N.HOUGHTON COUNTIES GIVEN THE EXTENSIVE WINDS AND SNOW.
OTHERWISE...KEPT THE REST OF THE CWA UNDER A WINTER STORM WATCH TO
PIN DOWN THE DETAILS. IF THE SYSTEM DOES SNEAK EASTWARD...WE MAY
NEED TO ADD ADDITIONAL COUNTIES INTO THE WARNING. MOST OF THE
UNCERTAINTIES WILL IMPACT THE CENTRAL/EASTERN COUNTIES THE MOST...SO
A WATCH SEEMED BEST RIGHT NOW.
FOR THE EXTENDED...WITH THE LINGERING UPPER LEVEL TROUGH IN THE
AREA...EXPECT COLDER TEMPERATURES TO RETURN. 850MB TEMPS WILL DROP
TOWARDS -25C TO -30C AS WE HEAD FURTHER INTO THE LATER TIME PERIODS.
SNOW WILL GRADUALLY CONFINE TO THE WEST WIND FAVORED REGIONS NEAR
LAKE SUPERIOR...AS ICE WILL LIKELY BE BROKEN ENOUGH TO INDUCE
INSTABILITY FOR LES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 653 PM EST WED FEB 19 2014
EXPECT VFR CONDITIONS TO PREVAIL AT ALL 3 TAF SITES THRU AT LEAST
THIS EVNG. BUT THE ARRIVAL OF MORE LLVL MSTR LATE TNGT IN THE PRESENCE
OF NOCTURNAL COOLING MIGHT RESULT IN SOME FOG AND LO CLD DEVELOPMENT...
ESPECIALLY AT SAW WITH MORE FVRBL UPSLOPE SSE WIND DIRECTION. BUT
INCRSG MID/HI CLDS WL LIMIT RADIATIONAL COOLING AND THE POTENTIAL FOR
IFR VSBYS/CIGS. AS DEEPENING LO PRES APRCHS UPR MI FM THE S ON THU...
EXPECT DETERIORATING CONDITIONS WITH GUSTY WINDS/SOME LGT SN AND
BLSN/MVFR CONDITIONS ARRIVING IN THE AFTN. AN EXTENDED PERIOD OF
CONDITIONS BLO AIRFIELD LANDING MINS IS POSSIBLE AT KCMX BEGINNING AT
SOME POINT THU NIGHT OR FRI MORNING AS THE MORE EXPOSED KEWEENAW
PENINSULA WL BE PLAGUED BY VERY STRONG E WINDS SHIFTING TO THE W AND
SN/BLSN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 PM EST WED FEB 19 2014
WINDS WILL DIMINISH THIS EVENING...BECOMING LIGHT UNDER 15KT. WINDS
WILL THEN BEGIN TO INCREASE OVERNIGHT AHEAD OF A WINTER STORM
ORGANIZING OVER THE SOUTHERN PLAINS. E TO NE WINDS MAY REACH UPWARDS
OF 30KT OVER FAR WRN LAKE SUPERIOR BY MORNING. WINDS WILL STEADILY
INCREASE ACROSS THE LAKE THU AS THE ORGANIZING LOW PRES SYSTEM LIFTS
INTO THE MID MISSISSIPPI VALLEY. THE LOW WILL THEN RAPIDLY DEEPEN...
BECOMING AN INTENSE LOW WITH PRES BOTTOMING OUT AROUND 28.7 INCHES
AS IT MOVES NNE ACROSS CNTRL UPPER MI AND CNTRL LAKE SUPERIOR LATE
THU NIGHT AND FRI MORNING. AHEAD OF THE LOW...EASTERLY GALES WILL
DEVELOP OVER CNTRL AND ERN LAKE SUPERIOR THU EVENING. WHILE E TO NE
GALES MAY ALSO DEVELOP OVER WRN LAKE SUPERIOR...W GALES ARE MORE
LIKELY IN THE WAKE OF THE LOW FRI/FRI NIGHT. GALES WILL CONTINUE
OVER CNTRL AND ERN LAKE SUPERIOR FRI THRU SAT WITH THE POTENTIAL FOR
STORM FORCE WINDS OVER ERN LAKE SUPERIOR FRI. ALTHOUGH GALES WILL
END BY SUN...WINDS WILL LIKELY REMAIN IN THE 20-30KT RANGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING FROM 4 PM EST /3 PM CST/ THURSDAY TO NOON
EST /11 AM CST/ FRIDAY FOR MIZ002-004-009-010-084.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ006-007-012>014-085.
BLIZZARD WARNING FROM 7 PM THURSDAY TO 10 PM EST FRIDAY FOR
MIZ001-003.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ005-011.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THURSDAY TO 6 PM EST SATURDAY FOR LSZ244-
245-264>267.
GALE WARNING FROM 7 AM EST /6 AM CST/ FRIDAY TO 7 AM EST /6 AM
CST/ SATURDAY FOR LSZ162-241>243-263.
LAKE MICHIGAN...
GALE WARNING FROM 7 PM THURSDAY TO 5 PM EST FRIDAY FOR LMZ221-
248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MCD
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
508 PM EST TUE FEB 18 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 405 PM EST TUE FEB 18 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A LOW AMPLITUDE TROF
MOVING ACROSS THE NCNTRL STATES/UPPER MISSISSIPPI VALLEY. THERE ARE
SEVERAL VORT MAXES WITHIN THE TROF. AHEAD OF ONE SHORTWAVE OVER NRN
ONTARIO INTO MN...RADAR RETURNS HAVE BEEN SHOWING UP IN NE MN AND
NOW ACROSS LAKE SUPERIOR. GIVEN DRY LOW-LEVELS...PCPN HAS NOT BEEN
ABLE TO REACH THE GROUND.
AS AFOREMENTIONED SHORTWAVE MOVES ACROSS THE UPPER LAKES TONIGHT...
NOT OUT OF THE QUESTION THAT PATCHY -SN/FLURRIES OR -FZDZ COULD
DEVELOP OVER THE ERN FCST AREA WHERE SHALLOW LOW-LEVEL MOISTURE HAS
ADVECTED N OFF LAKE MICHIGAN. IF LAYER BTWN THE MID LEVEL MOISTURE
AND SHALLOW MOISTURE OFF THE LAKE DOES NOT MOISTEN SUFFICIENTLY...
THEN -FZDZ WILL BE THE PTYPE IF ANY PCPN DOES OCCUR. ELSEWHERE...
HAVE SOME CONCERN FOR -FZDZ OVER THE KEWEENAW WITH WINDS SHIFTING TO
AN UPSLOPE WESTERLY DIRECTION WITH SFC TROF PASSAGE. THERE IS AN
AXIS OF SLIGHTLY HIGHER DWPTS THAT WILL BE ADVECTED INTO THE HIGHER
TERRAIN...AND THIS COULD LEAD TO POSSIBLE STRATUS/FOG AND EVEN
-FZDZ. HOWEVER...WITH FCST SOUNDINGS SHOWING ONLY A VERY SHALLOW SFC
BASED MOIST LAYER AND SINCE MUCH OF WRN LAKE SUPERIOR IS ICED OVER
TO GREATLY LIMIT ANY ADDITIONAL MOISTENING FROM THE LAKE...-FZDZ
POTENTIAL SEEMS VERY MINIMAL ATTM. OUTSIDE OF THOSE CONCERNS...
TONIGHT WILL BE ONE OF THE WARMER NIGHTS IN QUITE A WHILE UNDER
PACIFIC AIR MASS. EXPECT MIN TEMPS GENERALLY IN THE MID TEENS TO
LOWER 20S.
WED WILL BE A DRY DAY AS MIDLEVEL TROF SHIFTS E OF THE AREA AND
SHORTWAVE RIDGING BUILDS INTO THE WRN LAKES. WHILE THERE MIGHT BE
SOME LOW CLOUDS LINGERING INTO WED MORNING OVER THE NW AND MORE
LIKELY THE NE FCST AREA...EXPECT MOST AREAS TO SEE A GOOD DISPLAY OF
SUNSHINE WED. HIGHER MID TO LATE FEB SUN ANGLE WORKING ON THE LOWER
ALBEDO FORESTED TERRAIN WILL HELP TEMPS RISE WELL INTO THE 30S AND
EVEN INTO THE LWR 40S ACROSS MUCH OF THE FCST AREA. NOT OUT OF THE
QUESTION FOR A FEW LOCATIONS TO REACH THE MID 40S WHERE DOWNSLOPING
OCCURS. WITH W TO WNW WINDS FOR MUCH OF THE DAY...TEMPS WILL BE
COOLEST NEAR LAKE SUPERIOR OVER WRN UPPER MI AND OVER THE NE FCST
AREA. IN THOSE LOCATIONS...TEMPS SHOULD STRUGGLE TO RISE ABOVE
FREEZING NEAR THE LAKE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 505 PM EST TUE FEB 18 2014
WED NIGHT...
HIGH PRES AND CLEAR TO PARTLY CLOUDY SKIES WILL GIVE WAY
TO INCREASING SRLY WINDS AND MID/HIGH CLOUDS AS THE WAA REGIME
STRENGTHENS AHEAD OF THE MID LEVEL TROUGH OVER THE PLAINS AND SFC
TROUGH MOVING INTO THE UPPER MS VALLEY. LOWS ARE ONLY EXPECTED TO
DROP INTO THE LOWER 20S.
THURSDAY INTO FRIDAY...
THE MODELS HAVE COME INTO RELATIVELY GOOD AGREEMENT WITH THE TRACK
OF THE INTENSIFYING LOW PRESSURE SYSTEM MOVING INTO THE WRN GREAT
LAKES AND THE STRENGTH/POSITION OF THE MID LEVEL FEATURES. THE WPC
FAVORED ECMWF/GEM REMAINED A BIT FARTHER WEST WITH THE TRACK
COMPARED TO THE GFS. SINCE THE 12Z NAM WAS ALSO VERY CLOSE TO THE
ECMWF...IT WAS USED FOR MORE OF THE FCST DETAILS. THE LOW IS
EXPECTED TO RAPIDLY DEEPEN AS IT TRACKS NORTH FROM NEAR MKE AT
00Z/FRI TO NEAR MARQUETTE AT 06Z/FRI AND INTO NRN LAKE SUPERIOR AT
12Z/FRI.
THE POTENT MID LEVEL DYNAMICS WITH STRONG 700-300 QVECTOR CONV AND
FGEN COMBINED WITH ABUNDANT MOISTURE INFLOW SHOULD EASILY BE ABLE TO
PRODUCE QPF AMOUNTS AROUND AN INCH...ESPECIALLY OVER THE WEST THIRD
OF THE CWA. WITH AN ELEVATED DGZ AOA 10K FT...SLR ONLY AROUND 12Z/1
ARE EXPECTED LEADING TO SNOWFALL AMOUNTS AOA 10 INCHES OVER THE WEST
AND AROUND 6 INCHES CENTRAL. MIXED PCPN IS ALSO EXPECTED OVER THE
EAST HALF WITH AN 850-700 MB WARM LAYER MOVING LATE THU INTO THU
EVENING. WITH SFC TEMPS NEAR FREEZING...A MIX OF SN/PL/FZRA BEFORE
THE PCPN CHANGES BACK TO SNOW LATE. THERE IS STILL MORE UNCERTAINTY
ABOUT THE SNOW AMOUNTS AND PCPN TYPE TIMING OVER THE EAST HALF GIVEN
LINGERING MODEL DIFFERENCES. AS THE LOW MOVES NORTH OF UPPER MI LATE
THU NIGHT INTO FRI MORNING...STRONG WEST WINDS ARE EXPECTED TO
DEVELOP. NAM BUFKIT MIXED LAYER WINDS IN THE 40-50 KT RANGE OVER THE
KEWEENAW SUGGEST POTENTIAL FOR VERY STRONG SFC WINDS WITH SEVERE
BLOWING AND DRIFTING SNOW. SO...A BLIZZARD WATCH WAS POSTED FOR THE
KEWEENAW. OTHER LOCATIONS ACROSS THE CWA WILL ALSO BLSN BUT WILL
HAVE FEWER IMPACTS WITH A WEST WIND. THE WINDS WILL ONLY GRADUALLY
DIMINISH FRIDAY AFTERNOON INTO EVENING. ALTHOUGH THE STRONG WINDS
MAY BREAK UP SOME OF THE LAKE ICE...THE REMAINING EXTENSIVE ICE
COVER WILL SIGNIFICANTLY REDUCE CHANCE FOR ADDITIONAL LAKE ENHANCED
SNOW OR LES. HOWEVER...THE UPSLOPE TERRAIN ENHANCEMENT COULD STILL
BOOST SNOWFALL AMOUNTS OVER THE HIGHER TERRAIN OF THE NW CWA.
SAT-TUE...
ONLY SMALL CHANCE POPS WERE INCLUDED NEAR LAKE SUPERIOR FOR WNW/W
FLOW AREAS AS TEMPS ARE SUFFICIENTLY COLD FOR LAKE EFFECT RIGHT
THROUGH THE WEEKEND. WITH THE EXTENSIVE ICE ON LAKE SUPERIOR IT WILL
BE BE INTERESTING TO SEE HOW MUCH OPEN WATER DEVELOPS AFTER THE
STRONG WINDS EXPECTED ON FRIDAY. AWAY FROM ANY LAKE EFFECT...THE
RETURNING COLD WILL BE THE MAIN STORY WITH READINGS BOTH SATURDAY AND
SUNDAY IN THE TEENS. THE COLD REGIME LOOKS TO AS THE WRN CONUS RIDGE
REEMERGES AND ARCTIC HIGH PRES BUILDS INTO THE REGION FROM WRN
CANADA. HOWEVER...THE MODELS WERE LESS AGGRESSIVE IN BRINGING THE
VERY COLD AIR COMPARED TO PREVIOUS RUNS. TEMPS WILL REMAIN WELL BELOW
NORMAL WITH HIGHS FROM 10 TO 15 AND LOWS FROM ZERO TO AT LEAST 5
BELOW. WIND CHILLS MON AND TUE MORNING ARE ALSO EXPECTED TO DROP TO
NEAR 20 BELOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1239 PM EST TUE FEB 18 2014
PERSISTENT STRATUS AFFECTING KSAW WITH LIFR/IFR CIGS IS GRADUALLY
ERODING FROM THE EDGES. EXPECT A TREND TO VFR IN THE NEXT HR.
HOWEVER...ADDITIONAL STRATUS IS QUICKLY ADVECTING N UP LAKE MICHIGAN
AND MAY BRING LOW MVFR CIGS TO KSAW LATER THIS AFTN/EVENING. PASSAGE
OF SFC TROF AND WIND SHIFT TO A DOWNSLOPE W DIRECTION WILL BRING A
RETURN OF VFR LATE EVENING OR EARLY OVERNIGHT. TO THE W...KIWD/KCMX
WILL REMAIN VFR THIS AFTN. AXIS OF HIGH DWPTS ACCOMPANYING A WIND
SHIFT TO AN UPSLOPE W DIRECTION MAY BRING STRATUS/LOW MVFR CIG OR
PERHAPS IFR TO KCMX THIS EVENING. CLOUDS SHOULD SCATTER OUT
OVERNIGHT AS DRIER AIR ARRIVES. LOW CLOUDS APPEAR LESS LIKELY TO
FORM AT KIWD...BUT IT WILL BE SOMETHING TO MONITOR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST TUE FEB 18 2014
WINDS ARE FORECAST TO BE LESS THAN 30 KTS THROUGH WED. POTENTIAL FOR
A VERY STRONG LOW PRESSURE SYSTEM THURSDAY INTO FRIDAY WITH PRESSURE
LOWER THAN 975MB OR 29 INCHES TO LIFT ACROSS LAKE SUPERIOR THURSDAY
NIGHT AND INTO NORTHERN ONTARIO ON FRIDAY. NW GALES LIKELY LATE
THURSDAY NIGHT WITH WESTERLY GALES FRIDAY AND FRIDAY NIGHT. EVEN A
RISK OF STORM FORCE WINDS IF THIS SYSTEM TRENDS SLIGHTLY STRONGER.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ006-007-012>014-085.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ002-004-009-010-084.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ005-011.
BLIZZARD WATCH FROM THURSDAY EVENING THROUGH FRIDAY EVENING FOR
MIZ001-003.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
405 PM EST TUE FEB 18 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 405 PM EST TUE FEB 18 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A LOW AMPLITUDE TROF
MOVING ACROSS THE NCNTRL STATES/UPPER MISSISSIPPI VALLEY. THERE ARE
SEVERAL VORT MAXES WITHIN THE TROF. AHEAD OF ONE SHORTWAVE OVER NRN
ONTARIO INTO MN...RADAR RETURNS HAVE BEEN SHOWING UP IN NE MN AND
NOW ACROSS LAKE SUPERIOR. GIVEN DRY LOW-LEVELS...PCPN HAS NOT BEEN
ABLE TO REACH THE GROUND.
AS AFOREMENTIONED SHORTWAVE MOVES ACROSS THE UPPER LAKES TONIGHT...
NOT OUT OF THE QUESTION THAT PATCHY -SN/FLURRIES OR -FZDZ COULD
DEVELOP OVER THE ERN FCST AREA WHERE SHALLOW LOW-LEVEL MOISTURE HAS
ADVECTED N OFF LAKE MICHIGAN. IF LAYER BTWN THE MID LEVEL MOISTURE
AND SHALLOW MOISTURE OFF THE LAKE DOES NOT MOISTEN SUFFICIENTLY...
THEN -FZDZ WILL BE THE PTYPE IF ANY PCPN DOES OCCUR. ELSEWHERE...
HAVE SOME CONCERN FOR -FZDZ OVER THE KEWEENAW WITH WINDS SHIFTING TO
AN UPSLOPE WESTERLY DIRECTION WITH SFC TROF PASSAGE. THERE IS AN
AXIS OF SLIGHTLY HIGHER DWPTS THAT WILL BE ADVECTED INTO THE HIGHER
TERRAIN...AND THIS COULD LEAD TO POSSIBLE STRATUS/FOG AND EVEN
-FZDZ. HOWEVER...WITH FCST SOUNDINGS SHOWING ONLY A VERY SHALLOW SFC
BASED MOIST LAYER AND SINCE MUCH OF WRN LAKE SUPERIOR IS ICED OVER
TO GREATLY LIMIT ANY ADDITIONAL MOISTENING FROM THE LAKE...-FZDZ
POTENTIAL SEEMS VERY MINIMAL ATTM. OUTSIDE OF THOSE CONCERNS...
TONIGHT WILL BE ONE OF THE WARMER NIGHTS IN QUITE A WHILE UNDER
PACIFIC AIR MASS. EXPECT MIN TEMPS GENERALLY IN THE MID TEENS TO
LOWER 20S.
WED WILL BE A DRY DAY AS MIDLEVEL TROF SHIFTS E OF THE AREA AND
SHORTWAVE RIDGING BUILDS INTO THE WRN LAKES. WHILE THERE MIGHT BE
SOME LOW CLOUDS LINGERING INTO WED MORNING OVER THE NW AND MORE
LIKELY THE NE FCST AREA...EXPECT MOST AREAS TO SEE A GOOD DISPLAY OF
SUNSHINE WED. HIGHER MID TO LATE FEB SUN ANGLE WORKING ON THE LOWER
ALBEDO FORESTED TERRAIN WILL HELP TEMPS RISE WELL INTO THE 30S AND
EVEN INTO THE LWR 40S ACROSS MUCH OF THE FCST AREA. NOT OUT OF THE
QUESTION FOR A FEW LOCATIONS TO REACH THE MID 40S WHERE DOWNSLOPING
OCCURS. WITH W TO WNW WINDS FOR MUCH OF THE DAY...TEMPS WILL BE
COOLEST NEAR LAKE SUPERIOR OVER WRN UPPER MI AND OVER THE NE FCST
AREA. IN THOSE LOCATIONS...TEMPS SHOULD STRUGGLE TO RISE ABOVE
FREEZING NEAR THE LAKE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 439 AM EST TUE FEB 18 2014
WEATHER FOR WEDNESDAY INTO WEDNESDAY NIGHT QUIET COMPARED TO LATE
THIS WEEK. RAN WITH MENTION OF FZDZ OVR NORTHWEST AND NORTHEAST CWA
EARLY WEDNESDAY WHERE ONSHORE/UPSLOPING FLOW IS FORECAST ALONG WITH
MOISTURE TO H9 AND EVEN SOME LIFT WITHIN THAT MOIST LAYER. SPEED
SHEAR ALSO THERE WHICH CAN SOMETIMES ENHANCE DRIZZLE POTENTIAL. AFTER
LOW CLOUDS GET OUT OF THE WAY BY MIDDAY WEDNESDAY...NUDGED TEMPS UP
IN THE AFTN WITH READINGS OVER INTERIOR WEST AND SCNTRL POSSIBLY
CRACKING 40 DEGREES AS GEM GUIDANCE HAS SHOWN FOR A FEW DAYS NOW.
FORECAST GETS VERY INTERESTING BEYOND WEDNESDAY.
NO DOUBT ABOUT IT. MODELS CONTINUE TO LATCH ON TO THE POTENTIAL
FOR A VERY MAJOR AND HIGH IMPACT STORM ACROSS THE WESTERN GREAT
LAKES THURSDAY INTO FRIDAY. AND THIS IS JUST THE WINTER SIDE TO
THIS SYSTEM. SEVERE WEATHER...MAYBE EVEN FORM OF A LARGER SCALE
SQUALL LINE...COULD AFFECT OHIO VALLEY/TENNESSEE VALLEY AND MAYBE
AS FAR NORTH AS LOWER GREAT LAKES ON THE WARMER SIDE OF THE SYSTEM.
ON THAT FRONT...CANNOT RULE OUT ISOLD LIGHTNING STRIKES AS FAR NORTH
AS UPPER GREAT LAKES ON NOSE OF DRY SLOT WORKING THROUGH LATER
THURSDAY. SPC DAY3 OUTLOOK DOES HAVE EASTERN HALF OF UPR MICHIGAN IN
GENERAL THUNDER PROBS.
AGREEMENT AND CONSISTENCY IN MSLP/THERMAL FIELDS THE LAST FEW RUNS
FROM THE MAIN MEDIUM RANGE MODELS OF THE ECMWF/GFS/GEM-NH IS
IMPRESSIVE. ENTHUSIASM AND CONFIDENCE IN MODEL AGREEMENT IS TEMPERED
SOMEWHAT THOUGH AS PRIMARY SHORTWAVE THAT WILL HELP DEVELOP THE
STRONG SFC LOW IS STILL OVER THE GULF OF ALASKA THIS MORNING AND THE
FORECAST STRONG DEEPENING OF THE LOW AND ASSOCIATED PRECIP WITH IT
ARE DIRECTLY DEPENDANT ON PHASING OF SOUTHERN BRANCH SHORTWAVE WITH
INITIAL SHORTWAVE IN THE NORTHERN BRANCH. THIS IS ALWAYS A TRICKY
PROPOSITION. PROBABLY WILL SEE SOME SHIFTING AROUND IN TERMS OF
LOCATION AND STRENGTH OF LOW AND WARM LAYER ALOFT. IF IT ALL COMES TO
FRUITION AS MODELS CURRENTLY INDICATE THOUGH...SIGNIFICANT SNOWSTORM
WOULD IMPACT UPR MICHIGAN. WOULD ALSO BE ENOUGH WARM AIR ALOFT PER
1000-850/850-700MB THICKNESSES AND H85 TEMPS FOR SLEET AND FREEZING
RAIN OVER AT LEAST THE SOUTH AND EAST CWA...MAINLY ON THURSDAY NIGHT.
DEGREE OF ICING IS UNCERTAIN...AS IT WILL DEPEND ON TREATMENT OF
ROADS AND ALSO TIMING OF SWITCH OVER FROM SNOW TO RAIN. WPC WWD GRAPHICS
INDICATE SNOW AMOUNTS OVER WESTERN UPR MICHIGAN 12Z THURSDAY THROUGH
12Z FRIDAY OF 8-10 INCHES TAPERING TO 4-6 INCHES OVER EASTERN CWA ALONG
WITH ICE AMOUNTS THERE UP TO A TENTH OF AN INCH.
IMPACT TOWARD THE END OF THE PASSAGE OF THE LOW WOULD BE A FULL
FLEDGED BLIZZARD ALONG EXPOSED SHORELINE OF WESTERN LK SUPERIOR
LATE THURSDAY NIGHT INTO FRIDAY...MAINLY AFFECTING THE KEWEENAW
PENINSULA. FORECAST SUB 970MB LOW TO NORTH OF LK SUPERIOR AT 12Z
FRIDAY WITH WEST WINDS AT H85 OF 45 KTS AND SUFFICIENT MOIST
CYCLONIC FLOW AT H85-H7 WITH H85 TEMPS AROUND -12C WOULD BE BAD
ENOUGH ON ITS OWN. ADD FACT THAT WESTERN LK SUPERIOR IS COVERED WITH
ICE AND THERE WILL BE ONGOING SNOW AND BLOWING SNOW FROM THE LOW
PRESSURE SYSTEM AND IT CERTAINLY SEEMS THERE ARE THE MAKINGS OF
WIDESPREAD BLIZZARD CONDITIONS. MOST OF THE U.P. NEAR LAKE SUPERIOR
WOULD BE IMPACTED BY CONSIDERABLE BLSN DUE TO PROXIMITY OF THE SFC
LOW. WORST CONDITIONS WOULD BE ON THE KEWEENAW THOUGH. SYSTEM REALLY
BEARS WATCHING DUE TO THE POTENTIAL FOR SUCH HIGH IMPACTS FROM THE
SNOW...ICE...AND WIND. IF THIS SYSTEM ENDS UP AS FORECAST RIGHT
NOW...A WATCH WILL BE NEEDED. WILL START OUT HIGHLIGHTING IT THIS
MORNING BY ISSUING AN SPECIAL WEATHER STATEMENT. ALSO WILL KEEP
MENTION IN HAZARDOUS WEATHER OUTLOOK.
REST OF EXTENDED...KEPT WITH MONDAY DAYSHIFT THINKING OF SMALL CHANCE
POPS NEAR LK SUPERIOR FOR WNW/W FLOW AREAS AS TEMPS ARE SUFFICIENTLY
COLD FOR LAKE EFFECT RIGHT THROUGH THE WEEKEND. A LOT OF ICE ON LK
SUPERIOR BUT WILL BE INTERESTING TO SEE HOW MUCH OPEN WATER APPEARS
AFTER THE STRONG WINDS EXPECTED ON FRIDAY. AWAY FM ANY LAKE
EFFECT...THE RETURNING COLD WILL BE THE MAIN STORY WITH READINGS
BOTH SATURDAY AND SUNDAY IN THE TEENS. BEYOND THE EXTENDED...COLD
REGIME LOOKS TO REASSERT ITSELF AS WESTERN CONUS RIDGE TIED TO THE
PERSISTENT POSITIVE PNA PATTERN REAPPEARS. 00Z ECMWF BACKED OFF SOME
BUT STILL LOOKS QUITE COLD BY MIDDLE OF NEXT WEEK WITH H85 TEMPS DOWN
NEAR -28C. PROBABLY WILL BE DEALING WITH A RETURN OF WIND CHILL ISSUES
BY THAT TIME. MORAL OF THE STORY...ENJOY BRIEF RETURN OF WARMER TEMPS
AS BY THE WEEKEND AND BEYOND THEY WILL BE JUST A DISTANT MEMORY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1239 PM EST TUE FEB 18 2014
PERSISTENT STRATUS AFFECTING KSAW WITH LIFR/IFR CIGS IS GRADUALLY
ERODING FROM THE EDGES. EXPECT A TREND TO VFR IN THE NEXT HR.
HOWEVER...ADDITIONAL STRATUS IS QUICKLY ADVECTING N UP LAKE MICHIGAN
AND MAY BRING LOW MVFR CIGS TO KSAW LATER THIS AFTN/EVENING. PASSAGE
OF SFC TROF AND WIND SHIFT TO A DOWNSLOPE W DIRECTION WILL BRING A
RETURN OF VFR LATE EVENING OR EARLY OVERNIGHT. TO THE W...KIWD/KCMX
WILL REMAIN VFR THIS AFTN. AXIS OF HIGH DWPTS ACCOMPANYING A WIND
SHIFT TO AN UPSLOPE W DIRECTION MAY BRING STRATUS/LOW MVFR CIG OR
PERHAPS IFR TO KCMX THIS EVENING. CLOUDS SHOULD SCATTER OUT
OVERNIGHT AS DRIER AIR ARRIVES. LOW CLOUDS APPEAR LESS LIKELY TO
FORM AT KIWD...BUT IT WILL BE SOMETHING TO MONITOR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST TUE FEB 18 2014
WINDS ARE FORECAST TO BE LESS THAN 30 KTS THROUGH WED. POTENTIAL FOR
A VERY STRONG LOW PRESSURE SYSTEM THURSDAY INTO FRIDAY WITH PRESSURE
LOWER THAN 975MB OR 29 INCHES TO LIFT ACROSS LAKE SUPERIOR THURSDAY
NIGHT AND INTO NORTHERN ONTARIO ON FRIDAY. NW GALES LIKELY LATE
THURSDAY NIGHT WITH WESTERLY GALES FRIDAY AND FRIDAY NIGHT. EVEN A
RISK OF STORM FORCE WINDS IF THIS SYSTEM TRENDS SLIGHTLY STRONGER.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ006-007-012>014-085.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ002-004-009-010-084.
WINTER STORM WATCH FROM THURSDAY AFTERNOON THROUGH FRIDAY
MORNING FOR MIZ005-011.
BLIZZARD WATCH FROM THURSDAY EVENING THROUGH FRIDAY EVENING FOR
MIZ001-003.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1240 PM EST TUE FEB 18 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 509 AM EST TUE FEB 18 2014
09Z WV IMAGERY AND RUC ANALYSIS SHOWS THE STRONG SHORTWAVE
RESPONSIBLE FOR YESTERDAY/S SNOW IS NOW MOVING EAST THROUGH THE
LOWER GREAT LAKES. DEEP LAYER MOISTURE AND WEAK MID-LVL Q-VECT CONV
ASSOCIATED WITH THIS SYSTEM ARE ALSO PULLING OUT OF THE ERN FCST
AREA AS LIGHT SNOW HAS NOW ENDED OR DIMINISHED TO LITTLE MORE THAN
FLURRIES. AN AREA OF STRATUS CLOUDS STILL REMAIN OVER MAINLY THE WRN
FCST AREA BUT THESE CLOUDS SHOULD BREAK UP OR LIFT OUT THE AREA
SHORTLY AFTER SUNRISE WITH INCREASED MIXING FM WAA SOUTHERLY FLOW
AHEAD OF NEXT SYSTEM MOVING IN FM THE NORTHERN PLAINS.
TODAY...A COUPLE SHORTWAVES NOTED IN UPSTREAM ZONAL FLOW...ONE
NORTHERN WAVE MOVING EAST ACROSS MANITOBA INTO WRN ONTARIO AND A
SECOND SRN WAVE MOVING EAST ALONG THE SOUTH DAKOTA/NEBRASKA BORDER.
THESE WAVES WILL HELP PROPEL A WARM FRONT ACROSS THE FCST AREA THIS
MORNING TO BE FOLLOWED BY THE PASSAGE OF A SFC TROUGH AND WEAK COLD
FRONT TONIGHT. THE WEAK SHRTWV MOVING THROUGH NRN ONTARIO WILL BRUSH
LAKE SUPERIOR. A BAND OF 285-290K ISENTROPIC LIFT AHEAD OF THE
SHRTWV MAY PRODUCE SOME LIGHT SNOW...BUT BULK OF SNOW SHOULD REMAIN
MAINLY NORTH OF UPPER MI. OTHERWISE...FCST SNDGS AND LATEST IR
SATELLITE LOOP SUGGEST THERE SHOULD BE ENOUGH CLEARING AND SUNSHINE
FOR TEMPS TO CLIMB ABOVE NORMAL. SOUTHERLY FLOW WILL FAVOR THE WRN
HALF OF THE FCST FOR THE HIGHEST TEMPS RANGING FROM THE MID 30S TO
EVEN LOWER 40S FOR DOWNSLOPE LOCATIONS ALONG LAKE SUPERIOR. COOLER
SOUTH FLOW OFF MOSTLY ICE COVERED LAKE MI WILL KEEP ERN HALF OF CWA
COOLER...MAINLY IN THE LOWER 30S.
TONIGHT...NRN STREAM SHORTWAVE TROF WILL QUICKLY SHIFT ACROSS THE
WRN GREAT LAKES THIS EVENING ALONG WITH ASSOCIATED SFC TROUGH. NOT
EXPECTING MUCH IF ANY PCPN...AS DEEP LAYER FORCING/MID LEVEL
MOISTURE EXITS QUICKLY E OF THE FCST AREA IN THE EVENING. MAY SEE A
LITTLE BIT OF -SN/FLURRY ACTIVITY OVER THE E EARLY IN THE EVENING.
AFTER THAT...QUESTION IS WHETHER THERE MIGHT BE SOME LINGERING
FLURRIES OR MORE LIKELY PATCHY -FZDZ FOR AREAS FAVORED IN WNW
UPSLOPE FLOW AS TEMP PROFILE IN LINGERING SHALLOW MOISTURE IS ABOVE
-10C. BEST CHANCE FOR UPSLOPE PATCHY FZDZ WILL BE OVER THE KEWEENAW
AND FAR NE CWA. SHOULD BE ONE OF THE WARMER NIGHTS IN QUITE A WHILE
UNDER PACIFIC AIR MASS WITH WINDS HELPING TO KEEP TEMPS UP. EXPECT
MINS IN THE TEENS TO LOWER 20S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 439 AM EST TUE FEB 18 2014
WEATHER FOR WEDNESDAY INTO WEDNESDAY NIGHT QUIET COMPARED TO LATE
THIS WEEK. RAN WITH MENTION OF FZDZ OVR NORTHWEST AND NORTHEAST CWA
EARLY WEDNESDAY WHERE ONSHORE/UPSLOPING FLOW IS FORECAST ALONG WITH
MOISTURE TO H9 AND EVEN SOME LIFT WITHIN THAT MOIST LAYER. SPEED
SHEAR ALSO THERE WHICH CAN SOMETIMES ENHANCE DRIZZLE POTENTIAL. AFTER
LOW CLOUDS GET OUT OF THE WAY BY MIDDAY WEDNESDAY...NUDGED TEMPS UP
IN THE AFTN WITH READINGS OVER INTERIOR WEST AND SCNTRL POSSIBLY
CRACKING 40 DEGREES AS GEM GUIDANCE HAS SHOWN FOR A FEW DAYS NOW.
FORECAST GETS VERY INTERESTING BEYOND WEDNESDAY.
NO DOUBT ABOUT IT. MODELS CONTINUE TO LATCH ON TO THE POTENTIAL
FOR A VERY MAJOR AND HIGH IMPACT STORM ACROSS THE WESTERN GREAT
LAKES THURSDAY INTO FRIDAY. AND THIS IS JUST THE WINTER SIDE TO
THIS SYSTEM. SEVERE WEATHER...MAYBE EVEN FORM OF A LARGER SCALE
SQUALL LINE...COULD AFFECT OHIO VALLEY/TENNESSEE VALLEY AND MAYBE
AS FAR NORTH AS LOWER GREAT LAKES ON THE WARMER SIDE OF THE SYSTEM.
ON THAT FRONT...CANNOT RULE OUT ISOLD LIGHTNING STRIKES AS FAR NORTH
AS UPPER GREAT LAKES ON NOSE OF DRY SLOT WORKING THROUGH LATER
THURSDAY. SPC DAY3 OUTLOOK DOES HAVE EASTERN HALF OF UPR MICHIGAN IN
GENERAL THUNDER PROBS.
AGREEMENT AND CONSISTENCY IN MSLP/THERMAL FIELDS THE LAST FEW RUNS
FROM THE MAIN MEDIUM RANGE MODELS OF THE ECMWF/GFS/GEM-NH IS
IMPRESSIVE. ENTHUSIASM AND CONFIDENCE IN MODEL AGREEMENT IS TEMPERED
SOMEWHAT THOUGH AS PRIMARY SHORTWAVE THAT WILL HELP DEVELOP THE
STRONG SFC LOW IS STILL OVER THE GULF OF ALASKA THIS MORNING AND THE
FORECAST STRONG DEEPENING OF THE LOW AND ASSOCIATED PRECIP WITH IT
ARE DIRECTLY DEPENDANT ON PHASING OF SOUTHERN BRANCH SHORTWAVE WITH
INITIAL SHORTWAVE IN THE NORTHERN BRANCH. THIS IS ALWAYS A TRICKY
PROPOSITION. PROBABLY WILL SEE SOME SHIFTING AROUND IN TERMS OF
LOCATION AND STRENGTH OF LOW AND WARM LAYER ALOFT. IF IT ALL COMES TO
FRUITION AS MODELS CURRENTLY INDICATE THOUGH...SIGNIFICANT SNOWSTORM
WOULD IMPACT UPR MICHIGAN. WOULD ALSO BE ENOUGH WARM AIR ALOFT PER
1000-850/850-700MB THICKNESSES AND H85 TEMPS FOR SLEET AND FREEZING
RAIN OVER AT LEAST THE SOUTH AND EAST CWA...MAINLY ON THURSDAY NIGHT.
DEGREE OF ICING IS UNCERTAIN...AS IT WILL DEPEND ON TREATMENT OF
ROADS AND ALSO TIMING OF SWITCH OVER FROM SNOW TO RAIN. WPC WWD GRAPHICS
INDICATE SNOW AMOUNTS OVER WESTERN UPR MICHIGAN 12Z THURSDAY THROUGH
12Z FRIDAY OF 8-10 INCHES TAPERING TO 4-6 INCHES OVER EASTERN CWA ALONG
WITH ICE AMOUNTS THERE UP TO A TENTH OF AN INCH.
IMPACT TOWARD THE END OF THE PASSAGE OF THE LOW WOULD BE A FULL
FLEDGED BLIZZARD ALONG EXPOSED SHORELINE OF WESTERN LK SUPERIOR
LATE THURSDAY NIGHT INTO FRIDAY...MAINLY AFFECTING THE KEWEENAW
PENINSULA. FORECAST SUB 970MB LOW TO NORTH OF LK SUPERIOR AT 12Z
FRIDAY WITH WEST WINDS AT H85 OF 45 KTS AND SUFFICIENT MOIST
CYCLONIC FLOW AT H85-H7 WITH H85 TEMPS AROUND -12C WOULD BE BAD
ENOUGH ON ITS OWN. ADD FACT THAT WESTERN LK SUPERIOR IS COVERED WITH
ICE AND THERE WILL BE ONGOING SNOW AND BLOWING SNOW FROM THE LOW
PRESSURE SYSTEM AND IT CERTAINLY SEEMS THERE ARE THE MAKINGS OF
WIDESPREAD BLIZZARD CONDITIONS. MOST OF THE U.P. NEAR LAKE SUPERIOR
WOULD BE IMPACTED BY CONSIDERABLE BLSN DUE TO PROXIMITY OF THE SFC
LOW. WORST CONDITIONS WOULD BE ON THE KEWEENAW THOUGH. SYSTEM REALLY
BEARS WATCHING DUE TO THE POTENTIAL FOR SUCH HIGH IMPACTS FROM THE
SNOW...ICE...AND WIND. IF THIS SYSTEM ENDS UP AS FORECAST RIGHT
NOW...A WATCH WILL BE NEEDED. WILL START OUT HIGHLIGHTING IT THIS
MORNING BY ISSUING AN SPECIAL WEATHER STATEMENT. ALSO WILL KEEP
MENTION IN HAZARDOUS WEATHER OUTLOOK.
REST OF EXTENDED...KEPT WITH MONDAY DAYSHIFT THINKING OF SMALL CHANCE
POPS NEAR LK SUPERIOR FOR WNW/W FLOW AREAS AS TEMPS ARE SUFFICIENTLY
COLD FOR LAKE EFFECT RIGHT THROUGH THE WEEKEND. A LOT OF ICE ON LK
SUPERIOR BUT WILL BE INTERESTING TO SEE HOW MUCH OPEN WATER APPEARS
AFTER THE STRONG WINDS EXPECTED ON FRIDAY. AWAY FM ANY LAKE
EFFECT...THE RETURNING COLD WILL BE THE MAIN STORY WITH READINGS
BOTH SATURDAY AND SUNDAY IN THE TEENS. BEYOND THE EXTENDED...COLD
REGIME LOOKS TO REASSERT ITSELF AS WESTERN CONUS RIDGE TIED TO THE
PERSISTENT POSITIVE PNA PATTERN REAPPEARS. 00Z ECMWF BACKED OFF SOME
BUT STILL LOOKS QUITE COLD BY MIDDLE OF NEXT WEEK WITH H85 TEMPS DOWN
NEAR -28C. PROBABLY WILL BE DEALING WITH A RETURN OF WIND CHILL ISSUES
BY THAT TIME. MORAL OF THE STORY...ENJOY BRIEF RETURN OF WARMER TEMPS
AS BY THE WEEKEND AND BEYOND THEY WILL BE JUST A DISTANT MEMORY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1239 PM EST TUE FEB 18 2014
PERSISTENT STRATUS AFFECTING KSAW WITH LIFR/IFR CIGS IS GRADUALLY
ERODING FROM THE EDGES. EXPECT A TREND TO VFR IN THE NEXT HR.
HOWEVER...ADDITIONAL STRATUS IS QUICKLY ADVECTING N UP LAKE MICHIGAN
AND MAY BRING LOW MVFR CIGS TO KSAW LATER THIS AFTN/EVENING. PASSAGE
OF SFC TROF AND WIND SHIFT TO A DOWNSLOPE W DIRECTION WILL BRING A
RETURN OF VFR LATE EVENING OR EARLY OVERNIGHT. TO THE W...KIWD/KCMX
WILL REMAIN VFR THIS AFTN. AXIS OF HIGH DWPTS ACCOMPANYING A WIND
SHIFT TO AN UPSLOPE W DIRECTION MAY BRING STRATUS/LOW MVFR CIG OR
PERHAPS IFR TO KCMX THIS EVENING. CLOUDS SHOULD SCATTER OUT
OVERNIGHT AS DRIER AIR ARRIVES. LOW CLOUDS APPEAR LESS LIKELY TO
FORM AT KIWD...BUT IT WILL BE SOMETHING TO MONITOR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 439 AM EST TUE FEB 18 2014
WINDS ARE FORECAST TO BE LESS THAN 30 KTS THROUGH WED. POTENTIAL FOR
A VERY STRONG LOW PRESSURE SYSTEM THURSDAY INTO FRIDAY WITH PRESSURE
LOWER THAN 975MB OR 29 INCHES TO LIFT ACROSS LAKE SUPERIOR THURSDAY
NIGHT AND INTO NORTHERN ONTARIO ON FRIDAY. NW GALES LIKELY LATE
THURSDAY NIGHT WITH WESTERLY GALES FRIDAY AND FRIDAY NIGHT. EVEN A
RISK OF STORM FORCE WINDS IF THIS SYSTEM TRENDS SLIGHTLY STRONGER.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
709 AM EST TUE FEB 18 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 509 AM EST TUE FEB 18 2014
09Z WV IMAGERY AND RUC ANALYSIS SHOWS THE STRONG SHORTWAVE
RESPONSIBLE FOR YESTERDAY/S SNOW IS NOW MOVING EAST THROUGH THE
LOWER GREAT LAKES. DEEP LAYER MOISTURE AND WEAK MID-LVL Q-VECT CONV
ASSOCIATED WITH THIS SYSTEM ARE ALSO PULLING OUT OF THE ERN FCST
AREA AS LIGHT SNOW HAS NOW ENDED OR DIMINISHED TO LITTLE MORE THAN
FLURRIES. AN AREA OF STRATUS CLOUDS STILL REMAIN OVER MAINLY THE WRN
FCST AREA BUT THESE CLOUDS SHOULD BREAK UP OR LIFT OUT THE AREA
SHORTLY AFTER SUNRISE WITH INCREASED MIXING FM WAA SOUTHERLY FLOW
AHEAD OF NEXT SYSTEM MOVING IN FM THE NORTHERN PLAINS.
TODAY...A COUPLE SHORTWAVES NOTED IN UPSTREAM ZONAL FLOW...ONE
NORTHERN WAVE MOVING EAST ACROSS MANITOBA INTO WRN ONTARIO AND A
SECOND SRN WAVE MOVING EAST ALONG THE SOUTH DAKOTA/NEBRASKA BORDER.
THESE WAVES WILL HELP PROPEL A WARM FRONT ACROSS THE FCST AREA THIS
MORNING TO BE FOLLOWED BY THE PASSAGE OF A SFC TROUGH AND WEAK COLD
FRONT TONIGHT. THE WEAK SHRTWV MOVING THROUGH NRN ONTARIO WILL BRUSH
LAKE SUPERIOR. A BAND OF 285-290K ISENTROPIC LIFT AHEAD OF THE
SHRTWV MAY PRODUCE SOME LIGHT SNOW...BUT BULK OF SNOW SHOULD REMAIN
MAINLY NORTH OF UPPER MI. OTHERWISE...FCST SNDGS AND LATEST IR
SATELLITE LOOP SUGGEST THERE SHOULD BE ENOUGH CLEARING AND SUNSHINE
FOR TEMPS TO CLIMB ABOVE NORMAL. SOUTHERLY FLOW WILL FAVOR THE WRN
HALF OF THE FCST FOR THE HIGHEST TEMPS RANGING FROM THE MID 30S TO
EVEN LOWER 40S FOR DOWNSLOPE LOCATIONS ALONG LAKE SUPERIOR. COOLER
SOUTH FLOW OFF MOSTLY ICE COVERED LAKE MI WILL KEEP ERN HALF OF CWA
COOLER...MAINLY IN THE LOWER 30S.
TONIGHT...NRN STREAM SHORTWAVE TROF WILL QUICKLY SHIFT ACROSS THE
WRN GREAT LAKES THIS EVENING ALONG WITH ASSOCIATED SFC TROUGH. NOT
EXPECTING MUCH IF ANY PCPN...AS DEEP LAYER FORCING/MID LEVEL
MOISTURE EXITS QUICKLY E OF THE FCST AREA IN THE EVENING. MAY SEE A
LITTLE BIT OF -SN/FLURRY ACTIVITY OVER THE E EARLY IN THE EVENING.
AFTER THAT...QUESTION IS WHETHER THERE MIGHT BE SOME LINGERING
FLURRIES OR MORE LIKELY PATCHY -FZDZ FOR AREAS FAVORED IN WNW
UPSLOPE FLOW AS TEMP PROFILE IN LINGERING SHALLOW MOISTURE IS ABOVE
-10C. BEST CHANCE FOR UPSLOPE PATCHY FZDZ WILL BE OVER THE KEWEENAW
AND FAR NE CWA. SHOULD BE ONE OF THE WARMER NIGHTS IN QUITE A WHILE
UNDER PACIFIC AIR MASS WITH WINDS HELPING TO KEEP TEMPS UP. EXPECT
MINS IN THE TEENS TO LOWER 20S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 439 AM EST TUE FEB 18 2014
WEATHER FOR WEDNESDAY INTO WEDNESDAY NIGHT QUIET COMPARED TO LATE
THIS WEEK. RAN WITH MENTION OF FZDZ OVR NORTHWEST AND NORTHEAST CWA
EARLY WEDNESDAY WHERE ONSHORE/UPSLOPING FLOW IS FORECAST ALONG WITH
MOISTURE TO H9 AND EVEN SOME LIFT WITHIN THAT MOIST LAYER. SPEED
SHEAR ALSO THERE WHICH CAN SOMETIMES ENHANCE DRIZZLE POTENTIAL. AFTER
LOW CLOUDS GET OUT OF THE WAY BY MIDDAY WEDNESDAY...NUDGED TEMPS UP
IN THE AFTN WITH READINGS OVER INTERIOR WEST AND SCNTRL POSSIBLY
CRACKING 40 DEGREES AS GEM GUIDANCE HAS SHOWN FOR A FEW DAYS NOW.
FORECAST GETS VERY INTERESTING BEYOND WEDNESDAY.
NO DOUBT ABOUT IT. MODELS CONTINUE TO LATCH ON TO THE POTENTIAL
FOR A VERY MAJOR AND HIGH IMPACT STORM ACROSS THE WESTERN GREAT
LAKES THURSDAY INTO FRIDAY. AND THIS IS JUST THE WINTER SIDE TO
THIS SYSTEM. SEVERE WEATHER...MAYBE EVEN FORM OF A LARGER SCALE
SQUALL LINE...COULD AFFECT OHIO VALLEY/TENNESSEE VALLEY AND MAYBE
AS FAR NORTH AS LOWER GREAT LAKES ON THE WARMER SIDE OF THE SYSTEM.
ON THAT FRONT...CANNOT RULE OUT ISOLD LIGHTNING STRIKES AS FAR NORTH
AS UPPER GREAT LAKES ON NOSE OF DRY SLOT WORKING THROUGH LATER
THURSDAY. SPC DAY3 OUTLOOK DOES HAVE EASTERN HALF OF UPR MICHIGAN IN
GENERAL THUNDER PROBS.
AGREEMENT AND CONSISTENCY IN MSLP/THERMAL FIELDS THE LAST FEW RUNS
FROM THE MAIN MEDIUM RANGE MODELS OF THE ECMWF/GFS/GEM-NH IS
IMPRESSIVE. ENTHUSIASM AND CONFIDENCE IN MODEL AGREEMENT IS TEMPERED
SOMEWHAT THOUGH AS PRIMARY SHORTWAVE THAT WILL HELP DEVELOP THE
STRONG SFC LOW IS STILL OVER THE GULF OF ALASKA THIS MORNING AND THE
FORECAST STRONG DEEPENING OF THE LOW AND ASSOCIATED PRECIP WITH IT
ARE DIRECTLY DEPENDANT ON PHASING OF SOUTHERN BRANCH SHORTWAVE WITH
INITIAL SHORTWAVE IN THE NORTHERN BRANCH. THIS IS ALWAYS A TRICKY
PROPOSITION. PROBABLY WILL SEE SOME SHIFTING AROUND IN TERMS OF
LOCATION AND STRENGTH OF LOW AND WARM LAYER ALOFT. IF IT ALL COMES TO
FRUITION AS MODELS CURRENTLY INDICATE THOUGH...SIGNIFICANT SNOWSTORM
WOULD IMPACT UPR MICHIGAN. WOULD ALSO BE ENOUGH WARM AIR ALOFT PER
1000-850/850-700MB THICKNESSES AND H85 TEMPS FOR SLEET AND FREEZING
RAIN OVER AT LEAST THE SOUTH AND EAST CWA...MAINLY ON THURSDAY NIGHT.
DEGREE OF ICING IS UNCERTAIN...AS IT WILL DEPEND ON TREATMENT OF
ROADS AND ALSO TIMING OF SWITCH OVER FROM SNOW TO RAIN. WPC WWD GRAPHICS
INDICATE SNOW AMOUNTS OVER WESTERN UPR MICHIGAN 12Z THURSDAY THROUGH
12Z FRIDAY OF 8-10 INCHES TAPERING TO 4-6 INCHES OVER EASTERN CWA ALONG
WITH ICE AMOUNTS THERE UP TO A TENTH OF AN INCH.
IMPACT TOWARD THE END OF THE PASSAGE OF THE LOW WOULD BE A FULL
FLEDGED BLIZZARD ALONG EXPOSED SHORELINE OF WESTERN LK SUPERIOR
LATE THURSDAY NIGHT INTO FRIDAY...MAINLY AFFECTING THE KEWEENAW
PENINSULA. FORECAST SUB 970MB LOW TO NORTH OF LK SUPERIOR AT 12Z
FRIDAY WITH WEST WINDS AT H85 OF 45 KTS AND SUFFICIENT MOIST
CYCLONIC FLOW AT H85-H7 WITH H85 TEMPS AROUND -12C WOULD BE BAD
ENOUGH ON ITS OWN. ADD FACT THAT WESTERN LK SUPERIOR IS COVERED WITH
ICE AND THERE WILL BE ONGOING SNOW AND BLOWING SNOW FROM THE LOW
PRESSURE SYSTEM AND IT CERTAINLY SEEMS THERE ARE THE MAKINGS OF
WIDESPREAD BLIZZARD CONDITIONS. MOST OF THE U.P. NEAR LAKE SUPERIOR
WOULD BE IMPACTED BY CONSIDERABLE BLSN DUE TO PROXIMITY OF THE SFC
LOW. WORST CONDITIONS WOULD BE ON THE KEWEENAW THOUGH. SYSTEM REALLY
BEARS WATCHING DUE TO THE POTENTIAL FOR SUCH HIGH IMPACTS FROM THE
SNOW...ICE...AND WIND. IF THIS SYSTEM ENDS UP AS FORECAST RIGHT
NOW...A WATCH WILL BE NEEDED. WILL START OUT HIGHLIGHTING IT THIS
MORNING BY ISSUING AN SPECIAL WEATHER STATEMENT. ALSO WILL KEEP
MENTION IN HAZARDOUS WEATHER OUTLOOK.
REST OF EXTENDED...KEPT WITH MONDAY DAYSHIFT THINKING OF SMALL CHANCE
POPS NEAR LK SUPERIOR FOR WNW/W FLOW AREAS AS TEMPS ARE SUFFICIENTLY
COLD FOR LAKE EFFECT RIGHT THROUGH THE WEEKEND. A LOT OF ICE ON LK
SUPERIOR BUT WILL BE INTERESTING TO SEE HOW MUCH OPEN WATER APPEARS
AFTER THE STRONG WINDS EXPECTED ON FRIDAY. AWAY FM ANY LAKE
EFFECT...THE RETURNING COLD WILL BE THE MAIN STORY WITH READINGS
BOTH SATURDAY AND SUNDAY IN THE TEENS. BEYOND THE EXTENDED...COLD
REGIME LOOKS TO REASSERT ITSELF AS WESTERN CONUS RIDGE TIED TO THE
PERSISTENT POSITIVE PNA PATTERN REAPPEARS. 00Z ECMWF BACKED OFF SOME
BUT STILL LOOKS QUITE COLD BY MIDDLE OF NEXT WEEK WITH H85 TEMPS DOWN
NEAR -28C. PROBABLY WILL BE DEALING WITH A RETURN OF WIND CHILL ISSUES
BY THAT TIME. MORAL OF THE STORY...ENJOY BRIEF RETURN OF WARMER TEMPS
AS BY THE WEEKEND AND BEYOND THEY WILL BE JUST A DISTANT MEMORY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 645 AM EST TUE FEB 18 2014
EXPECT PREVAILING VFR CONDITIONS AT ALL THREE TAF SITES UNTIL THIS
EVENING. AS WINDS SHIFT WEST THIS EVENING BEHIND THE PASSAGE OF A
TROUGH...UPSLOPE MVFR CLOUDS AND A COMBINATION OF FLURRIES AND FZDZ
COULD DEVELOP AT KCMX AND PERHAPS KIWD AS WELL. DOWNSLOPE WESTERLY
FLOW AT KSAW SHOULD MAINTAIN VFR CONDITIONS THERE THROUGH THE PERIOD.
&&
MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 439
AM EST TUE FEB 18 2014
WINDS ARE FORECAST TO BE LESS THAN 30 KTS THROUGH WED. POTENTIAL FOR
A VERY STRONG LOW PRESSURE SYSTEM THURSDAY INTO FRIDAY WITH PRESSURE
LOWER THAN 975MB OR 29 INCHES TO LIFT ACROSS LAKE SUPERIOR THURSDAY
NIGHT AND INTO NORTHERN ONTARIO ON FRIDAY. NW GALES LIKELY LATE
THURSDAY NIGHT WITH WESTERLY GALES FRIDAY AND FRIDAY NIGHT. EVEN A
RISK OF STORM FORCE WINDS IF THIS SYSTEM TRENDS SLIGHTLY STRONGER.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...VOSS
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
509 AM EST TUE FEB 18 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 509 AM EST TUE FEB 18 2014
09Z WV IMAGERY AND RUC ANALYSIS SHOWS THE STRONG SHORTWAVE
RESPONSIBLE FOR YESTERDAY/S SNOW IS NOW MOVING EAST THROUGH THE
LOWER GREAT LAKES. DEEP LAYER MOISTURE AND WEAK MID-LVL Q-VECT CONV
ASSOCIATED WITH THIS SYSTEM ARE ALSO PULLING OUT OF THE ERN FCST
AREA AS LIGHT SNOW HAS NOW ENDED OR DIMINISHED TO LITTLE MORE THAN
FLURRIES. AN AREA OF STRATUS CLOUDS STILL REMAIN OVER MAINLY THE WRN
FCST AREA BUT THESE CLOUDS SHOULD BREAK UP OR LIFT OUT THE AREA
SHORTLY AFTER SUNRISE WITH INCREASED MIXING FM WAA SOUTHERLY FLOW
AHEAD OF NEXT SYSTEM MOVING IN FM THE NORTHERN PLAINS.
TODAY...A COUPLE SHORTWAVES NOTED IN UPSTREAM ZONAL FLOW...ONE
NORTHERN WAVE MOVING EAST ACROSS MANITOBA INTO WRN ONTARIO AND A
SECOND SRN WAVE MOVING EAST ALONG THE SOUTH DAKOTA/NEBRASKA BORDER.
THESE WAVES WILL HELP PROPEL A WARM FRONT ACROSS THE FCST AREA THIS
MORNING TO BE FOLLOWED BY THE PASSAGE OF A SFC TROUGH AND WEAK COLD
FRONT TONIGHT. THE WEAK SHRTWV MOVING THROUGH NRN ONTARIO WILL BRUSH
LAKE SUPERIOR. A BAND OF 285-290K ISENTROPIC LIFT AHEAD OF THE
SHRTWV MAY PRODUCE SOME LIGHT SNOW...BUT BULK OF SNOW SHOULD REMAIN
MAINLY NORTH OF UPPER MI. OTHERWISE...FCST SNDGS AND LATEST IR
SATELLITE LOOP SUGGEST THERE SHOULD BE ENOUGH CLEARING AND SUNSHINE
FOR TEMPS TO CLIMB ABOVE NORMAL. SOUTHERLY FLOW WILL FAVOR THE WRN
HALF OF THE FCST FOR THE HIGHEST TEMPS RANGING FROM THE MID 30S TO
EVEN LOWER 40S FOR DOWNSLOPE LOCATIONS ALONG LAKE SUPERIOR. COOLER
SOUTH FLOW OFF MOSTLY ICE COVERED LAKE MI WILL KEEP ERN HALF OF CWA
COOLER...MAINLY IN THE LOWER 30S.
TONIGHT...NRN STREAM SHORTWAVE TROF WILL QUICKLY SHIFT ACROSS THE
WRN GREAT LAKES THIS EVENING ALONG WITH ASSOCIATED SFC TROUGH. NOT
EXPECTING MUCH IF ANY PCPN...AS DEEP LAYER FORCING/MID LEVEL
MOISTURE EXITS QUICKLY E OF THE FCST AREA IN THE EVENING. MAY SEE A
LITTLE BIT OF -SN/FLURRY ACTIVITY OVER THE E EARLY IN THE EVENING.
AFTER THAT...QUESTION IS WHETHER THERE MIGHT BE SOME LINGERING
FLURRIES OR MORE LIKELY PATCHY -FZDZ FOR AREAS FAVORED IN WNW
UPSLOPE FLOW AS TEMP PROFILE IN LINGERING SHALLOW MOISTURE IS ABOVE
-10C. BEST CHANCE FOR UPSLOPE PATCHY FZDZ WILL BE OVER THE KEWEENAW
AND FAR NE CWA. SHOULD BE ONE OF THE WARMER NIGHTS IN QUITE A WHILE
UNDER PACIFIC AIR MASS WITH WINDS HELPING TO KEEP TEMPS UP. EXPECT
MINS IN THE TEENS TO LOWER 20S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 439 AM EST TUE FEB 18 2014
WEATHER FOR WEDNESDAY INTO WEDNESDAY NIGHT QUIET COMPARED TO LATE
THIS WEEK. RAN WITH MENTION OF FZDZ OVR NORTHWEST AND NORTHEAST CWA
EARLY WEDNESDAY WHERE ONSHORE/UPSLOPING FLOW IS FORECAST ALONG WITH
MOISTURE TO H9 AND EVEN SOME LIFT WITHIN THAT MOIST LAYER. SPEED
SHEAR ALSO THERE WHICH CAN SOMETIMES ENHANCE DRIZZLE POTENTIAL. AFTER
LOW CLOUDS GET OUT OF THE WAY BY MIDDAY WEDNESDAY...NUDGED TEMPS UP
IN THE AFTN WITH READINGS OVER INTERIOR WEST AND SCNTRL POSSIBLY
CRACKING 40 DEGREES AS GEM GUIDANCE HAS SHOWN FOR A FEW DAYS NOW.
FORECAST GETS VERY INTERESTING BEYOND WEDNESDAY.
NO DOUBT ABOUT IT. MODELS CONTINUE TO LATCH ON TO THE POTENTIAL
FOR A VERY MAJOR AND HIGH IMPACT STORM ACROSS THE WESTERN GREAT
LAKES THURSDAY INTO FRIDAY. AND THIS IS JUST THE WINTER SIDE TO
THIS SYSTEM. SEVERE WEATHER...MAYBE EVEN FORM OF A LARGER SCALE
SQUALL LINE...COULD AFFECT OHIO VALLEY/TENNESSEE VALLEY AND MAYBE
AS FAR NORTH AS LOWER GREAT LAKES ON THE WARMER SIDE OF THE SYSTEM.
ON THAT FRONT...CANNOT RULE OUT ISOLD LIGHTNING STRIKES AS FAR NORTH
AS UPPER GREAT LAKES ON NOSE OF DRY SLOT WORKING THROUGH LATER
THURSDAY. SPC DAY3 OUTLOOK DOES HAVE EASTERN HALF OF UPR MICHIGAN IN
GENERAL THUNDER PROBS.
AGREEMENT AND CONSISTENCY IN MSLP/THERMAL FIELDS THE LAST FEW RUNS
FROM THE MAIN MEDIUM RANGE MODELS OF THE ECMWF/GFS/GEM-NH IS
IMPRESSIVE. ENTHUSIASM AND CONFIDENCE IN MODEL AGREEMENT IS TEMPERED
SOMEWHAT THOUGH AS PRIMARY SHORTWAVE THAT WILL HELP DEVELOP THE
STRONG SFC LOW IS STILL OVER THE GULF OF ALASKA THIS MORNING AND THE
FORECAST STRONG DEEPENING OF THE LOW AND ASSOCIATED PRECIP WITH IT
ARE DIRECTLY DEPENDANT ON PHASING OF SOUTHERN BRANCH SHORTWAVE WITH
INITIAL SHORTWAVE IN THE NORTHERN BRANCH. THIS IS ALWAYS A TRICKY
PROPOSITION. PROBABLY WILL SEE SOME SHIFTING AROUND IN TERMS OF
LOCATION AND STRENGTH OF LOW AND WARM LAYER ALOFT. IF IT ALL COMES TO
FRUITION AS MODELS CURRENTLY INDICATE THOUGH...SIGNIFICANT SNOWSTORM
WOULD IMPACT UPR MICHIGAN. WOULD ALSO BE ENOUGH WARM AIR ALOFT PER
1000-850/850-700MB THICKNESSES AND H85 TEMPS FOR SLEET AND FREEZING
RAIN OVER AT LEAST THE SOUTH AND EAST CWA...MAINLY ON THURSDAY NIGHT.
DEGREE OF ICING IS UNCERTAIN...AS IT WILL DEPEND ON TREATMENT OF
ROADS AND ALSO TIMING OF SWITCH OVER FROM SNOW TO RAIN. WPC WWD GRAPHICS
INDICATE SNOW AMOUNTS OVER WESTERN UPR MICHIGAN 12Z THURSDAY THROUGH
12Z FRIDAY OF 8-10 INCHES TAPERING TO 4-6 INCHES OVER EASTERN CWA ALONG
WITH ICE AMOUNTS THERE UP TO A TENTH OF AN INCH.
IMPACT TOWARD THE END OF THE PASSAGE OF THE LOW WOULD BE A FULL
FLEDGED BLIZZARD ALONG EXPOSED SHORELINE OF WESTERN LK SUPERIOR
LATE THURSDAY NIGHT INTO FRIDAY...MAINLY AFFECTING THE KEWEENAW
PENINSULA. FORECAST SUB 970MB LOW TO NORTH OF LK SUPERIOR AT 12Z
FRIDAY WITH WEST WINDS AT H85 OF 45 KTS AND SUFFICIENT MOIST
CYCLONIC FLOW AT H85-H7 WITH H85 TEMPS AROUND -12C WOULD BE BAD
ENOUGH ON ITS OWN. ADD FACT THAT WESTERN LK SUPERIOR IS COVERED WITH
ICE AND THERE WILL BE ONGOING SNOW AND BLOWING SNOW FROM THE LOW
PRESSURE SYSTEM AND IT CERTAINLY SEEMS THERE ARE THE MAKINGS OF
WIDESPREAD BLIZZARD CONDITIONS. MOST OF THE U.P. NEAR LAKE SUPERIOR
WOULD BE IMPACTED BY CONSIDERABLE BLSN DUE TO PROXIMITY OF THE SFC
LOW. WORST CONDITIONS WOULD BE ON THE KEWEENAW THOUGH. SYSTEM REALLY
BEARS WATCHING DUE TO THE POTENTIAL FOR SUCH HIGH IMPACTS FROM THE
SNOW...ICE...AND WIND. IF THIS SYSTEM ENDS UP AS FORECAST RIGHT
NOW...A WATCH WILL BE NEEDED. WILL START OUT HIGHLIGHTING IT THIS
MORNING BY ISSUING AN SPECIAL WEATHER STATEMENT. ALSO WILL KEEP
MENTION IN HAZARDOUS WEATHER OUTLOOK.
REST OF EXTENDED...KEPT WITH MONDAY DAYSHIFT THINKING OF SMALL CHANCE
POPS NEAR LK SUPERIOR FOR WNW/W FLOW AREAS AS TEMPS ARE SUFFICIENTLY
COLD FOR LAKE EFFECT RIGHT THROUGH THE WEEKEND. A LOT OF ICE ON LK
SUPERIOR BUT WILL BE INTERESTING TO SEE HOW MUCH OPEN WATER APPEARS
AFTER THE STRONG WINDS EXPECTED ON FRIDAY. AWAY FM ANY LAKE
EFFECT...THE RETURNING COLD WILL BE THE MAIN STORY WITH READINGS
BOTH SATURDAY AND SUNDAY IN THE TEENS. BEYOND THE EXTENDED...COLD
REGIME LOOKS TO REASSERT ITSELF AS WESTERN CONUS RIDGE TIED TO THE
PERSISTENT POSITIVE PNA PATTERN REAPPEARS. 00Z ECMWF BACKED OFF SOME
BUT STILL LOOKS QUITE COLD BY MIDDLE OF NEXT WEEK WITH H85 TEMPS DOWN
NEAR -28C. PROBABLY WILL BE DEALING WITH A RETURN OF WIND CHILL ISSUES
BY THAT TIME. MORAL OF THE STORY...ENJOY BRIEF RETURN OF WARMER TEMPS
AS BY THE WEEKEND AND BEYOND THEY WILL BE JUST A DISTANT MEMORY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1245 AM EST TUE FEB 18 2014
GRADUALLY IMPROVING CONDITIONS SHOULD OCCUR AT ALL THREE TAF SITES
THROUGH THE NIGHT AS SNOW TAPERS OFF AND WITH DRIER AIR MOVING INTO
THE AREA CIGS WILL IMPROVE TO VFR BY MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 439 AM EST TUE FEB 18 2014
WINDS ARE FORECAST TO BE LESS THAN 30 KTS THROUGH WED. POTENTIAL FOR
A VERY STRONG LOW PRESSURE SYSTEM THURSDAY INTO FRIDAY WITH PRESSURE
LOWER THAN 975MB OR 29 INCHES TO LIFT ACROSS LAKE SUPERIOR THURSDAY
NIGHT AND INTO NORTHERN ONTARIO ON FRIDAY. NW GALES LIKELY LATE
THURSDAY NIGHT WITH WESTERLY GALES FRIDAY AND FRIDAY NIGHT. EVEN A
RISK OF STORM FORCE WINDS IF THIS SYSTEM TRENDS SLIGHTLY STRONGER.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...JLA
AVIATION...MZ
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
448 AM EST TUE FEB 18 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 445 PM EST MON FEB 17 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH
THROUGH THE UPPER MS VALLEY WITH SEVERAL EMBEDDED SHRTWVS...THE
STRONGEST OF WHICH WAS LOCATED OVER CNTRL IL. MODERATE 700-300 MB
QVECTOR CONV FARTHER NORTH AHEAD OF A WEAKER SHRTWV OVER NW WI
SUPPORTED LIGHT TO MODERATE SNOW FORM NRN WI THROUGH UPPER MI.
TONIGHT...RADAR/SATELLITE TRENDS AND SHORT RANGE MODELS SUGGEST THAT
THE HEAVIER SNOW THIS EVENING WILL REMAIN ACROSS SRN PORTION OF THE
CWA...WHERE ADDITIONAL AMOUNTS OF 1 TO 3 INCHES ARE LIKELY AFTER
21Z. DEEP MOISTURE QUICKLY EXITS FROM WEST TO EAST THIS EVENING AS
SHORTWAVE DEPARTS SE OF REGION AND LEVEL RIDGING BUILDS IN WITH
STRONG MID LVL SUBSIDENCE AND DRYING LATE TONIGHT.
TUESDAY...ANOTHER WEAK SHRTWV MOVING THROUGH NRN ONTARIO WILL BRUSH
LAKE SUPERIOR. A BAND OF 290K ISENTROPIC LIFT AHEAD OF THE SHRTWV
MAY PRODUCE SOME LIGHT SNOW...BUT SHOULD REMAIN MAINLY NORTH OF
UPPER MI. OTHERWISE...925-850 MB RH FCST SUGGESTS THAT THERE WILL BE
ENOUGH CLEARING AND SUNSHINE FOR TEMPS TO CLIMB ABOVE NORMAL INTO
THE LOW AND MID 30S NORTH AND EAST AND THE UPPER 30S SOUTH.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 439 AM EST TUE FEB 18 2014
WEATHER FOR WEDNESDAY INTO WEDNESDAY NIGHT QUIET COMPARED TO LATE
THIS WEEK. RAN WITH MENTION OF FZDZ OVR NORTHWEST AND NORTHEAST CWA
EARLY WEDNESDAY WHERE ONSHORE/UPSLOPING FLOW IS FORECAST ALONG WITH
MOISTURE TO H9 AND EVEN SOME LIFT WITHIN THAT MOIST LAYER. SPEED
SHEAR ALSO THERE WHICH CAN SOMETIMES ENHANCE DRIZZLE POTENTIAL. AFTER
LOW CLOUDS GET OUT OF THE WAY BY MIDDAY WEDNESDAY...NUDGED TEMPS UP
IN THE AFTN WITH READINGS OVER INTERIOR WEST AND SCNTRL POSSIBLY
CRACKING 40 DEGREES AS GEM GUIDANCE HAS SHOWN FOR A FEW DAYS NOW.
FORECAST GETS VERY INTERESTING BEYOND WEDNESDAY.
NO DOUBT ABOUT IT. MODELS CONTINUE TO LATCH ON TO THE POTENTIAL
FOR A VERY MAJOR AND HIGH IMPACT STORM ACROSS THE WESTERN GREAT
LAKES THURSDAY INTO FRIDAY. AND THIS IS JUST THE WINTER SIDE TO
THIS SYSTEM. SEVERE WEATHER...MAYBE EVEN FORM OF A LARGER SCALE
SQUALL LINE...COULD AFFECT OHIO VALLEY/TENNESSEE VALLEY AND MAYBE
AS FAR NORTH AS LOWER GREAT LAKES ON THE WARMER SIDE OF THE SYSTEM.
ON THAT FRONT...CANNOT RULE OUT ISOLD LIGHTNING STRIKES AS FAR NORTH
AS UPPER GREAT LAKES ON NOSE OF DRY SLOT WORKING THROUGH LATER
THURSDAY. SPC DAY3 OUTLOOK DOES HAVE EASTERN HALF OF UPR MICHIGAN IN
GENERAL THUNDER PROBS.
AGREEMENT AND CONSISTENCY IN MSLP/THERMAL FIELDS THE LAST FEW RUNS
FROM THE MAIN MEDIUM RANGE MODELS OF THE ECMWF/GFS/GEM-NH IS
IMPRESSIVE. ENTHUSIASM AND CONFIDENCE IN MODEL AGREEMENT IS TEMPERED
SOMEWHAT THOUGH AS PRIMARY SHORTWAVE THAT WILL HELP DEVELOP THE
STRONG SFC LOW IS STILL OVER THE GULF OF ALASKA THIS MORNING AND THE
FORECAST STRONG DEEPENING OF THE LOW AND ASSOCIATED PRECIP WITH IT
ARE DIRECTLY DEPENDANT ON PHASING OF SOUTHERN BRANCH SHORTWAVE WITH
INITIAL SHORTWAVE IN THE NORTHERN BRANCH. THIS IS ALWAYS A TRICKY
PROPOSITION. PROBABLY WILL SEE SOME SHIFTING AROUND IN TERMS OF
LOCATION AND STRENGTH OF LOW AND WARM LAYER ALOFT. IF IT ALL COMES TO
FRUITION AS MODELS CURRENTLY INDICATE THOUGH...SIGNIFICANT SNOWSTORM
WOULD IMPACT UPR MICHIGAN. WOULD ALSO BE ENOUGH WARM AIR ALOFT PER
1000-850/850-700MB THICKNESSES AND H85 TEMPS FOR SLEET AND FREEZING
RAIN OVER AT LEAST THE SOUTH AND EAST CWA...MAINLY ON THURSDAY NIGHT.
DEGREE OF ICING IS UNCERTAIN...AS IT WILL DEPEND ON TREATMENT OF
ROADS AND ALSO TIMING OF SWITCH OVER FROM SNOW TO RAIN. WPC WWD GRAPHICS
INDICATE SNOW AMOUNTS OVER WESTERN UPR MICHIGAN 12Z THURSDAY THROUGH
12Z FRIDAY OF 8-10 INCHES TAPERING TO 4-6 INCHES OVER EASTERN CWA ALONG
WITH ICE AMOUNTS THERE UP TO A TENTH OF AN INCH.
IMPACT TOWARD THE END OF THE PASSAGE OF THE LOW WOULD BE A FULL
FLEDGED BLIZZARD ALONG EXPOSED SHORELINE OF WESTERN LK SUPERIOR
LATE THURSDAY NIGHT INTO FRIDAY...MAINLY AFFECTING THE KEWEENAW
PENINSULA. FORECAST SUB 970MB LOW TO NORTH OF LK SUPERIOR AT 12Z
FRIDAY WITH WEST WINDS AT H85 OF 45 KTS AND SUFFICIENT MOIST
CYCLONIC FLOW AT H85-H7 WITH H85 TEMPS AROUND -12C WOULD BE BAD
ENOUGH ON ITS OWN. ADD FACT THAT WESTERN LK SUPERIOR IS COVERED WITH
ICE AND THERE WILL BE ONGOING SNOW AND BLOWING SNOW FROM THE LOW
PRESSURE SYSTEM AND IT CERTAINLY SEEMS THERE ARE THE MAKINGS OF
WIDESPREAD BLIZZARD CONDITIONS. MOST OF THE U.P. NEAR LAKE SUPERIOR
WOULD BE IMPACTED BY CONSIDERABLE BLSN DUE TO PROXIMITY OF THE SFC
LOW. WORST CONDITIONS WOULD BE ON THE KEWEENAW THOUGH. SYSTEM REALLY
BEARS WATCHING DUE TO THE POTENTIAL FOR SUCH HIGH IMPACTS FROM THE
SNOW...ICE...AND WIND. IF THIS SYSTEM ENDS UP AS FORECAST RIGHT
NOW...A WATCH WILL BE NEEDED. WILL START OUT HIGHLIGHTING IT THIS
MORNING BY ISSUING AN SPECIAL WEATHER STATEMENT. ALSO WILL KEEP
MENTION IN HAZARDOUS WEATHER OUTLOOK.
REST OF EXTENDED...KEPT WITH MONDAY DAYSHIFT THINKING OF SMALL CHANCE
POPS NEAR LK SUPERIOR FOR WNW/W FLOW AREAS AS TEMPS ARE SUFFICIENTLY
COLD FOR LAKE EFFECT RIGHT THROUGH THE WEEKEND. A LOT OF ICE ON LK
SUPERIOR BUT WILL BE INTERESTING TO SEE HOW MUCH OPEN WATER APPEARS
AFTER THE STRONG WINDS EXPECTED ON FRIDAY. AWAY FM ANY LAKE
EFFECT...THE RETURNING COLD WILL BE THE MAIN STORY WITH READINGS
BOTH SATURDAY AND SUNDAY IN THE TEENS. BEYOND THE EXTENDED...COLD
REGIME LOOKS TO REASSERT ITSELF AS WESTERN CONUS RIDGE TIED TO THE
PERSISTENT POSITIVE PNA PATTERN REAPPEARS. 00Z ECMWF BACKED OFF SOME
BUT STILL LOOKS QUITE COLD BY MIDDLE OF NEXT WEEK WITH H85 TEMPS DOWN
NEAR -28C. PROBABLY WILL BE DEALING WITH A RETURN OF WIND CHILL ISSUES
BY THAT TIME. MORAL OF THE STORY...ENJOY BRIEF RETURN OF WARMER TEMPS
AS BY THE WEEKEND AND BEYOND THEY WILL BE JUST A DISTANT MEMORY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1245 AM EST TUE FEB 18 2014
GRADUALLY IMPROVING CONDITIONS SHOULD OCCUR AT ALL THREE TAF SITES
THROUGH THE NIGHT AS SNOW TAPERS OFF AND WITH DRIER AIR MOVING INTO
THE AREA CIGS WILL IMPROVE TO VFR BY MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 439 AM EST TUE FEB 18 2014
WINDS ARE FORECAST TO BE LESS THAN 30 KTS THROUGH WED. POTENTIAL FOR
A VERY STRONG LOW PRESSURE SYSTEM THURSDAY INTO FRIDAY WITH PRESSURE
LOWER THAN 975MB OR 29 INCHES TO LIFT ACROSS LAKE SUPERIOR THURSDAY
NIGHT AND INTO NORTHERN ONTARIO ON FRIDAY. NW GALES LIKELY LATE
THURSDAY NIGHT WITH WESTERLY GALES FRIDAY AND FRIDAY NIGHT. EVEN A
RISK OF STORM FORCE WINDS IF THIS SYSTEM TRENDS SLIGHTLY STRONGER.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...MZ
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1246 AM EST TUE FEB 18 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 445 PM EST MON FEB 17 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH
THROUGH THE UPPER MS VALLEY WITH SEVERAL EMBEDDED SHRTWVS...THE
STRONGEST OF WHICH WAS LOCATED OVER CNTRL IL. MODERATE 700-300 MB
QVECTOR CONV FARTHER NORTH AHEAD OF A WEAKER SHRTWV OVER NW WI
SUPPORTED LIGHT TO MODERATE SNOW FORM NRN WI THROUGH UPPER MI.
TONIGHT...RADAR/SATELLITE TRENDS AND SHORT RANGE MODELS SUGGEST THAT
THE HEAVIER SNOW THIS EVENING WILL REMAIN ACROSS SRN PORTION OF THE
CWA...WHERE ADDITIONAL AMOUNTS OF 1 TO 3 INCHES ARE LIKELY AFTER
21Z. DEEP MOISTURE QUICKLY EXITS FROM WEST TO EAST THIS EVENING AS
SHORTWAVE DEPARTS SE OF REGION AND LEVEL RIDGING BUILDS IN WITH
STRONG MID LVL SUBSIDENCE AND DRYING LATE TONIGHT.
TUESDAY...ANOTHER WEAK SHRTWV MOVING THROUGH NRN ONTARIO WILL BRUSH
LAKE SUPERIOR. A BAND OF 290K ISENTROPIC LIFT AHEAD OF THE SHRTWV
MAY PRODUCE SOME LIGHT SNOW...BUT SHOULD REMAIN MAINLY NORTH OF
UPPER MI. OTHERWISE...925-850 MB RH FCST SUGGESTS THAT THERE WILL BE
ENOUGH CLEARING AND SUNSHINE FOR TEMPS TO CLIMB ABOVE NORMAL INTO
THE LOW AND MID 30S NORTH AND EAST AND THE UPPER 30S SOUTH.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 445 PM EST MON FEB 17 2014
PROGRESSIVE/LOWER AMPLITUDE PATTERN WILL LEAD TO A PERIOD OF WARMER
WEATHER AND ABOVE NORMAL TEMPS CENTERED ON THE MIDWEEK PERIOD.
HOWEVER...THE WARMTH WILL BE SHORT-LIVED. ALL INDICATIONS POINT
TOWARD THE RETURN OF A STRONG RIDGE CENTERED ALONG OR SLIGHTLY
INLAND OF THE WEST COAST THIS WEEKEND INTO NEXT WEEK. MANY OF THE
GEM ENSEMBLES OVER THE LAST FEW DAYS HAVE INDICATED A VERY COLD
REGIME FOR LATE FEB NEXT WEEK...AND NOW TODAYS 12Z ECMWF SHOWS A
BITTERLY COLD AIR MASS DUMPING INTO THE UPPER LAKES DURING THE
MIDDLE OF NEXT WEEK WITH A REINFORCING SHOT UPSTREAM YET.
DETERMINISTIC GFS RUNS OUT TO 16 DAYS HAVE SHOWN WIDE FLUCTUATION IN
THE LAST DAY OR SO... BUT RUNS KEEP APPEARING THAT MAINTAIN A VERY
AMPLIFIED PATTERN OF WRN RIDGE/ERN TROF...LEADING TO A VERY COLD
PERIOD FOR THE UPPER LAKES. IN ANY EVENT...AS THIS CHANGE BACK TO A
COLD PATTERN GETS UNDERWAY...ATTENTION WILL BE ON AN AMPLIFYING TROF
SHIFTING ACROSS THE CONUS DURING THE MID AND LATE WEEK. OVER THE
LAST SEVERAL DAYS...MODELS HAVE STRUGGLED WITH PHASING OF SHORTWAVES
WITHIN THE DEEPENING TROF. HOWEVER...WITH TODAYS 12Z MEDIUM RANGE
MODEL RUNS...THERE ARE SOLID TRENDS TOWARD MUCH BETTER AGREEMENT ON
A SRN STREAM WAVE LIFTING NE AND PHASING WITH A NRN BRANCH WAVE OVER
AND JUST NE OF THE GREAT LAKES. THIS WILL LEAD TO THE ONLY
SIGNIFICANT PCPN EVENT (SNOW AND MIXED PCPN) DURING THE LONG TERM
PORTION OF THE FCST. OUTSIDE OF THIS ONE EVENT...NOT MUCH PCPN IS
EXPECTED DURING THE LONG TERM.
BEGINNING TUE NIGHT...NEXT SHORTWAVE TROF WILL QUICKLY SHIFT ACROSS
THE WRN GREAT LAKES. WITH SEVERAL DISJOINTED VORT CENTERS COMPRISING
THE TROF...NOT EXPECTING MUCH IF ANY PCPN...ESPECIALLY WITH DEEP
LAYER FORCING/MID LEVEL MOISTURE EXITING TO THE E OF THE AREA
ALREADY IN THE EVENING. BEFORE THAT HAPPENS...MAY SEE A LITTLE BIT
OF -SN/FLURRY ACTIVITY OVER THE E EARLY IN THE EVENING. AFTER
THAT...QUESTION IS WHETHER THERE MIGHT BE SOME FLURRIES OR MORE
LIKELY -FZDZ AS TEMP PROFILE IN LINGERING GENERALLY SHALLOW MOISTURE
IS ABOVE -10C. UNDER W TO WNW LOW-LEVEL WINDS...BEST CHANCE WOULD BE
OVER THE UPSLOPE AREAS OF WRN UPPER MI AND PERHAPS THE FAR NE FCST
AREA AS WINDS VEER WNW THERE LATER IN THE NIGHT. SINCE ANY
ADDITIONAL MOISTENING THAT COULD BE PROVIDED BY LAKE SUPERIOR IS
VERY LIMITED AS THE LAKE IS NEARLY COMPLETELY ICED OVER...WILL HOLD
OFF ON INCLUDING A MENTION OF -FZDZ. TUE NIGHT WILL BE ONE OF THE
WARMER NIGHTS IN QUITE A WHILE UNDER PACIFIC AIR MASS WITH WINDS
HELPING TO KEEP TEMPS UP. EXPECT MINS IN THE TEENS TO LOWER 20S.
WED WILL BE A DRY DAY AS SHORTWAVE TROF SHIFTS E OF THE AREA AND
SHORTWAVE RIDGING BUILDS INTO THE WRN LAKES. WHILE THERE MIGHT BE
SOME LOW CLOUDS LINGERING INTO WED MORNING...EXPECT MOST AREAS TO
SEE A GOOD DISPLAY OF SUNSHINE WED. HIGHER MID TO LATE FEB SUN ANGLE
WORKING ON THE LOWER ALBEDO FORESTED TERRAIN WILL HELP TEMPS RISE
INTO THE 30S ACROSS THE BOARD. MAY NOT BE OUT OF THE QUESTION FOR A
FEW LOCATIONS TO REACH 40F WHERE DOWNSLOPING OCCURS. WITH W TO WNW
WINDS FOR MUCH OF THE DAY...TEMPS WILL BE COOLEST NEAR LAKE SUPERIOR
OVER WRN UPPER MI AND OVER THE NE FCST AREA. IN THOSE LOCATIONS...
TEMPS SHOULDN`T RISE ABOVE FREEZING.
AS ALLUDED TO ABOVE...MEDIUM RANGE GUIDANCE HAS STRONGLY TRENDED
TOWARD MUCH BETTER AGREEMENT WITH THE DETAILS OF AMPLIFYING TROF
SHIFTING ACROSS THE CONUS MID AND LATE WEEK. ALTHOUGH THE MODEL
AGREEMENT THAT HAS APPEARED WITH TODAYS 12Z MODEL RUNS IS RATHER
REMARKABLE GIVEN THE VERY RECENT DISAGREEMENT...THE SHORTWAVES
INVOLVED ARE STILL IN THE GULF OF ALASKA AND ALEUTIANS...SUGGESTING
CONTINUED ADJUSTMENTS ARE IN THE OFFING. THAT SAID...THE
GEM/GFS/ECMWF ARE IN EXCELLENT AGREEMENT TODAY SHOWING A SRN STREAM
SHORTWAVE MOVING OUT OVER THE SRN PLAINS THU AND THEN LIFTING NE AND
PHASING WITH NRN STREAM ENERGY OVER THE UPPER MISSISSIPPI VALLEY.
RESULT IS A SFC LOW OVER THE SRN PLAINS THU MORNING LIFTING NE
ACROSS NW IL AND THEN RAPIDLY DEEPENING AS IT MOVES JUST E OF KGRB
THEN ACROSS ERN LAKE SUPERIOR THU NIGHT. WITH 12HR HEIGHT FALLS OF
250-300M AT 500MB...THIS WILL BE A VERY DYNAMIC SYSTEM WITH A
RAPIDLY ORGANIZING/INTENSIFYING PCPN SHIELD AS IT MOVES ACROSS THE
UPPER LAKES. WITH SYSTEM TAPPING A GOOD FEED OF GULF MOISTURE...
STRONG DYNAMICS WILL MAKE THIS A SIGNIFICANT PCPN PRODUCER ACROSS
MUCH OF UPPER MI. BASED OFF 12Z MODELS WHICH ARE IN GOOD
AGREEMENT...PTYPE SHOULD BE JUST SNOW W OF LINE ROUGHLY FROM JUST NW
MENOMINEE TO AROUND MUNISING WITH A WINTRY MIX TO THE E FOR AT LEAST
A TIME. HOWEVER...UNTIL SHORTWAVES INVOLVED ARRIVE IN THE
CONUS/CANADA...EXPECT SOME FLUCTUATION IN SYSTEM STRENGTH/TRACK AND
THERMAL FIELDS/PTYPES. POPS WILL BE RAISED ACROSS THE BOARD TO
CATEGORICAL FOR AT LEAST A PORTION OF THU AFTN/NIGHT. DEPENDING ON
EXACTLY HOW STRONG THE LOW BECOMES...WINDS/BLSN COULD BECOME
SIGNIFICANT ON THE BACKSIDE. RIGHT NOW...IT APPEARS BACKSIDE WINDS
WILL BE FROM A W TO WNW DIRECTION. IF SO...THOUGH FALLING SNOW WILL
BE MUCH LIGHTER...BLIZZARD CONDITIONS WILL BE POSSIBLE OVER THE
KEWEENAW WITH THE ADDED COMPONENT OF BLSN OFF LAKE SUPERIOR ICE
COVER. STRONG WINDS WILL LIKELY LOOSEN UP ICE COVER AND CREATE
SUFFICIENT BREAKS FOR SOME LES OFF LAKE SUPERIOR AFTER THE SYNOPTIC
MOISTURE PULLS OUT FRI AND 850MB TEMPS FALL INTO THE MID -TEENS C.
ARCTIC AIR BECOMES RE-ESTABLISHED OVER THE GREAT LAKES OVER THE
WEEKEND INTO NEXT WEEK. HOW COLD IS UNCERTAIN...BUT TEMPS SHOULD BE
SOLIDLY BLO NORMAL WITH A TREND TO COLDER CONDITIONS EARLY NEXT WEEK
AND BEYOND. WHILE THERE MAY BE SOME -SN AT TIMES AND PROBABLY SOME
LIMITED LAKE EFFECT OFF LAKE SUPERIOR DUE TO FRACTURED ICE
COVER/SMALL OPEN WATER AREAS...NO PCPN OF SIGNIFICANCE IS
ANTICIPATED AT THIS POINT SAT THRU MON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1245 AM EST TUE FEB 18 2014
GRADUALLY IMPROVING CONDITIONS SHOULD OCCUR AT ALL THREE TAF SITES
THROUGH THE NIGHT AS SNOW TAPERS OFF AND WITH DRIER AIR MOVING INTO
THE AREA CIGS WILL IMPROVE TO VFR BY MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 PM EST MON FEB 17 2014
WINDS ARE FORECAST TO BE LESS THAN 30 KTS THROUGH WED. THERE IS THE
POTENTIAL FOR A STRONG LOW PRESSURE SYSTEM TO MOVE THROUGH LAKE
SUPERIOR THURSDAY NIGHT AND INTO NORTHERN ONTARIO FRIDAY. THIS WOULD
LIKELY BRING A PERIOD OF NORTHWEST TO WEST GALES LATE THURSDAY NIGHT
THROUGH FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 1 AM EST EARLY THIS MORNING FOR
MIZ006-007-014-085.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...ROLFSON
AVIATION...MZ
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1152 PM EST MON FEB 17 2014
.AVIATION...
//DISCUSSION...
SNOW CONTINUES TO TAPER OFF AS LOW PRESSURE LIFTS OUT OF SOUTHEAST
MICHIGAN. CONDITIONS SHOULD SETTLE INTO THE MVFR CATEGORY...WITH IFR
CONDITIONS POSSIBLE THROUGH 10Z AS MODERATE SNOW CONTINUES TO MOVE
THROUGH THE TAF SITES. DOPPLER RADAR SHOWS A BRIEF BREAK CURRENTLY
OVER THE TAF SITES...WITH ANOTHER BAND OF SNOW EXPECTED TO TRACK
THROUGH DURING THE EARLY MORNING HOURS ON TUESDAY. ADDITIONAL
ACCUMULATIONS WILL BE LIGHT...GENERALLY 1 TO 2 INCHES. CONDITIONS
ARE EXPECTED TO IMPROVE TO VFR LATER THIS MORNING AND CONTINUE INTO
THE AFTERNOON HOURS AS THE LOW TRACKS TO THE EAST AS WINDS PICK UP
BEHIND THE LOW.
FOR DTW...MVFR CONDITIONS ARE EXPECTED THIS MORNING AS ANOTHER BAND
OF SNOW OCCASIONALLY BRINGS CONDITIONS DOWN TO IFR. CONDITIONS ARE
EXPECTED TO IMPROVE TO VFR LATER THIS MORNING.
//DTW THRESHOLD THREATS...
* HIGH CONFIDENCE IN CEILING BELOW 5000 FT LATE THROUGH THIS MORNING.
* HIGH CONFIDENCE IN PRECIPITATION TYPE AS SNOW.
&&
.PREV DISCUSSION...ISSUED 720 PM EST MON FEB 17 2014
UPDATE...
UPDATED EARLY TO ISSUE THE UPGRADE TO A WINTER STORM WARNING FOR
THE TRI CITIES AND NORTHERN THUMB. STRONG ISENTROPIC LIFT PRODUCED
RATES IN THE 1-2 INCH PER HOUR RANGE IN THE TRI CITIES WITH THE
DEFORMATION/TROWAL PORTION OF THE SYSTEM YET TO GO. DRY AIR IN
BETWEEN HAS THINGS OFF TO A SLOW START SOUTH OF INTERSTATE 69 BUT
THIS WILL BE MADE UP FOR BY BANDS OF MODERATE TO HEAVY SNOW,
IMPLIED BY 1/2 TO 1/4 MILE VISIBILITY, FROM ACTIVITY MOVING IN
FROM INDIANA AND OHIO.
THE LEADING QUICK 2 INCH ACCUMULATION IN THE TRI CITIES MADE THE
UPGRADE CALL A BIT EASIER EVEN WITH SOME UNCERTAINTY LEFT ON THE
THE TROWAL/DEFORMATION AXIS PROGRESSION. EVEN WITHOUT A PIVOT, THE
NORTH FLANK OF THE CIRCULATION NOW LOOKS CAPABLE OF 6 INCHES IN 9
HOURS OR POSSIBLY 8 INCHES IN 12 HOURS BEFORE THE SYSTEM EXITS
INTO ONTARIO BETWEEN 3 AM AND 6 AM. THE NORTHWARD INTRUSION OF THE
DRY SLOT WILL KEEP TOTAL ACCUMULATION IN THE ADVISORY RANGE OVER
THE REST OF SE MICHIGAN. THIS WILL BE ESPECIALLY TRUE NEAR THE
OHIO BORDER WHERE SNOW PELLETS, WHILE REPRESENTING CONVECTIVE
FORCING, WILL ACTUALLY CUT INTO SNOW RATIO ENOUGH TO LIMIT
ACCUMULATION.
PREV DISCUSSION...ISSUED 353 PM EST MON FEB 17 2014
SHORT TERM... AFTERNOON THROUGH TONIGHT
THE WINTER WEATHER ADVISORY WILL REMAIN IN EFFECT TONIGHT FOR HIGH
END ADVISORY SNOW ACCUMULATION. THE RANGE OF 3 TO 6 INCHES WILL
LIKELY VERIFY CLOSER TO THE 6 INCH END OF THE RANGE FOR MOST
LOCATIONS. LOCALLY HIGHER AMOUNTS AND A SHORT FUSED WARNING
UPGRADE ALSO REMAINS IN PLAY AS THE POSITION AND CHARACTER OF
MESOSCALE FORCING BECOMES CLEARER. THIS WOULD MOST LIKELY BE IN
THE TRI CITIES TO NORTHERN THUMB BASED ON OBSERVATIONS AS THEY
BECOME AVAILABLE DURING THE LATE AFTERNOON INTO EARLY EVENING. THE
MAIN UNCERTAINTY WITH AN UPGRADE LIES WITH THE PROGRESSION VERSUS
PIVOT OF THE DEFORMATION AXIS ON THE NORTH FLANK OF THE SYSTEM AND
THE NORTHWARD PUSH OF THE DRY SLOT. OBSERVATIONS WILL BE
MONITORED FOR A PIVOT WHICH WOULD PERMIT HIGHER RATES FOR A LONGER
PERIOD OF TIME AND HIGHER SYSTEM TOTALS AND/OR 6 INCH AMOUNTS
COMING IN CLOSER TO 6 TO 9 HOUR TIME PERIOD. FARTHER SOUTH, A
CONVECTIVE COMPONENT IN THE FORCING WILL BRING HIGH SNOWFALL RATES
AND EVEN SOME GRAUPEL/SNOW PELLETS WITH A RUMBLE OF THUNDER AT
TIMES BEFORE THE MID LEVEL DRY SLOT CONFINES TOTAL ACCUMULATION
CLOSER TO 4 INCHES.
MID AFTERNOON SATELLITE IMAGERY SHOWS THE LOW PRESSURE SYSTEM OVER
ILLINOIS/INDIANA COMING TOGETHER IN A STRONGLY DYNAMIC FASHION.
VISIBILITY NEAR ZERO IN SURFACE OBSERVATIONS WITH SEVERAL CLUSTERS
OF CG LIGHTNING STRIKES DEPICTS THE CONVECTIVE NATURE OF THE
SITUATION, AS DOES THE SPECIAL 18Z KILX SOUNDING WITH BORDERLINE DRY
ADIABATIC LAPSE RATES IN THE 700-500 MB LAYER. NEAR TERM MODEL
FIELDS HAVE PICKED UP ON THIS AS A STRONG COMBINATION OF MID LEVEL
DCVA AND LOW LEVEL THETA-E ADVECTION ON 850 MB WIND PUSHING 50
KNOTS. THE WIND FIELD WILL EVENTUALLY GET CONVERTED TO TROWAL
FORCING WITH SPECIFIC HUMIDITY SETTLING IN AROUND 3 G/KG. THE
TROWAL/DEFORMATION AXIS IS EXPECTED TO SET UP NORTH OF THE
INTERSTATE 69 CORRIDOR AS THE SURFACE LOW DROPS FROM 1007 MB TO NEAR
1000 MB OVER THE EAST SHORE OF LAKE ST CLAIR BY MIDNIGHT. AS
MENTIONED ABOVE, THERE WILL BE CONVECTIVE INSTABILITY BOTH WITHIN
THE WARM ADVECTION PATTERN AND ON THE INTERIOR FLANK OF THE
TROWAL/THETA-E RIDGE. THIS THERMODYNAMIC ENVIRONMENT COUPLED WITH
THE STRONG WIND FIELD WILL RESULT IN SNOWFALL RATES IN THE 1-2 INCH
PER HOUR RANGE. IN ADDITION, MODEL SOUNDINGS INDICATE FAVORABLE
TEMPERATURE AND MOISTURE PROFILES THAT DEPICT A DGZ DEPTH ROUGHLY
FROM 600 TO 800 MB THAT SHOULD SUPPORT SNOW RATIO IN THE 10-13:1
RANGE. THE NAM AND THE RAP MODELS SEEMINGLY HAVE ALSO PICKED UP ON
THE COMBINATION OF HIGHER MOISTURE CONTENT AND STRONG DYNAMIC
FORCING REFLECTED IN LIQUID EQUIVALENT QPF RANGING FROM 0.6 TO 0.8
IN THE 12 HOUR PERIOD FROM 18Z TO 06Z TONIGHT. THIS ILLUSTRATES THE
POTENTIAL FOR OVERACHIEVEMENT SHOULD MESOSCALE FORCING STALL OVER
ANY ONE REGION OF SE MICHIGAN DURING THE EVENING. THE SYSTEM WILL
THEN MOVE EASTWARD ENOUGH OVERNIGHT FOR SNOW TO DIMINISH ON THE
WESTERN FLANK OF THE UPPER CIRCULATION BY SUNRISE TUESDAY
MORNING.
LONG TERM...TUESDAY THROUGH SUNDAY
PROGRESSIVE LOW AMPLITUDE LONGWAVE PATTERN WILL CONTINUE THROUGH THE
MID WEEK BEFORE BROAD TROUGH SETS UP ACROSS MUCH OF THE CENTRAL
CONUS AND GREAT LAKES THROUGH THE WEEKEND. THE ENERGETIC JET WILL
SHIFT FAR ENOUGH NORTH TO ALLOW A WARMUP THROUGH THE MID WEEK PERIOD
WITH TEMPS IN THE MID 30S AND EVEN NEAR 40F BEFORE THE NEXT TROUGH
AND STRONG SYSTEM PUSHES THE MILD AIR SOUTH DROPPING US BACK INTO
THE 20S. THE DIFFICULTY IN THE TEMP FORECAST WILL BE TAKING INTO
ACCOUNT THE DEEP SNOWPACK THAT IS PRESENT ACROSS THE AREA.
THERE MAY BE SOME LINGERING LIGHT SNOW SHOWERS OR FLURRIES OVER THE
AREA TUESDAY MORNING AS THE BACK EDGE OF MONDAYS SYSTEM HOLDS OVER
THE AREA. AS THIS EXITS...A FRONTAL BOUNDARY EXTENDING SOUTHEAST
FROM A MUCH LARGER SYSTEM OVER CENTRAL CANADA WILL LIFT NORTH
THROUGH THE GREAT LAKES. THIS...ALONG WITH A SHORTWAVE RIDGE
BUILDING ACROSS THE AREA...WILL LEAD TO INCREASING SW FLOW AND A WAA
PATTERN. LOW LEVEL TEMPS WILL CLIMB FROM -8C/-12C AT 850MB/925MB
CURRENTLY UP TO AROUND 3-5C BY LATE TUESDAY AFTERNOON. MODEL
SOUNDING KEEP THE BOUNDARY MUCH COOLER THOUGH WITH TEMPS STILL BELOW
0C. GUSTY WINDS SHOULD BE ABLE TO MIX SOME OF THAT DOWN BUT THE COLD
DEEP SNOWPACK WILL WORK AGAINST IT MUCH OF TIME. WITH THE WARMEST
AIR TAKING SO LONG TO GET INTO THE AREA...HAVE KEPT HIGH TEMPS
AROUND THE MID 30S FOR NOW.
WEDNESDAYS FORECAST WILL ALSO BE A TRICKY ONE AS A COLD FRONT WILL
SWEEP THROUGH THE AREA IN THE MORNING. THERE IS A LOW CHANCE THAT WE
COULD SEE SOME SNOW FLAKES FROM THIS FRONT BUT NOT MUCH IN THE WAY
OF ACCUMULATIONS. LOW LEVEL THERMAL PROFILE DOES NOT TANK MUCH AS
RIDGING QUICKLY BUILDS IN THE WAKE OF THIS FRONT. MID LEVELS DO COOL
QUITE A BIT THOUGH. WITH SFC HIGH PRESSURE BRINGING MOSTLY CLEAR
SKIES...SHOULD NOT BE TOO HARD TO GET BACK INTO THE MID/UPPER 30S
EVEN WITH SFC-800MB TEMPS HOVERING AROUND 0C. POTENTIAL TO ADD A
DEGREE OR TWO TO THE FORECAST BUT ONCE AGAIN WOULD LIKE TO SEE HOW
SEVERE THE SNOW PACK AFFECTS THINGS BEFORE GOING TOO HIGH.
LOW PRESSURE ORIGINATING FROM THE TEXAS PANHANDLE WILL TRACK
NORTHEAST TOWARD THE GREAT LAKES BY THURSDAY. THE TRACK AND
ORIENTATION OF THIS SYSTEM WILL ALLOW MOISTURE FROM THE GULF OF
MEXICO TO ENHANCE QPF AMOUNTS AND ALSO WARM THE SYSTEM CONSIDERABLY.
EXPECTING BETWEEN 0.5 AND 1.0 INCHES OF RAINFALL ALONG WITH
CONSIDERABLE SNOWMELT FROM THIS SYSTEM...WHICH MAY LEAD TO
RIVER/AREAL FLOOD ISSUES. AVERAGE SNOW CORES ACROSS THE REGION ARE
OVER 3 INCHES OF LIQUID EQUIVALENT IN 16 INCHES OF SNOW
DEPTH...EXCLUDING THE 3-6 INCHES EXPECTED TONIGHT.
MARINE...
A LOW PRESSURE SYSTEM WILL TRACK FROM SOUTH OF LAKE MICHIGAN ACROSS
TO WESTERN LAKE ERIE AND NORTHEAST THROUGH LAKE ST CLAIR TONIGHT.
THIS WILL PRODUCE A PERIOD OF HEAVY SNOW THIS EVENING. GUSTY
WESTERLY WINDS WILL FOLLOW THE SYSTEM ON TUESDAY MORNING WITH THE
POTENTIAL TO BRIEFLY TOP 25 KNOTS OVER LAKE ERIE AND LAKE ST CLAIR.
WINDS WILL RELAX SOME TUESDAY AFTERNOON AS A RIDGE OF HIGH PRESSURE
BUILDS INTO THE REGION. A WEAK COLD FRONT COULD AGAIN LEAD TO GUSTY
WINDS ON WEDNESDAY BUT THIS TIME OUT OF THE NORTHWEST. SUBSTANTIAL
ICE COVERAGE ACROSS ALL MARINE AREAS WILL KEEP WAVES ABSENT FROM ALL
FORECAST PRODUCTS.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING...MIZ047-MIZ048-MIZ049-MIZ053-MIZ054...UNTIL 4
AM TUESDAY.
WINTER WEATHER ADVISORY...MIZ055-MIZ060-MIZ061-MIZ062-MIZ063-MIZ068-
MIZ069-MIZ070-MIZ075-MIZ076-MIZ082-MIZ083...UNTIL 4 AM TUESDAY.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....KURIMSKI
UPDATE.......BT
SHORT TERM...BT
LONG TERM....DRK/MM
MARINE.......DRK
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
836 PM CST Wed Feb 19 2014
.UPDATE:
Issued at 836 PM CST Wed Feb 19 2014
Having serious concerns that PoPs tonight are too high across
much of the area. Latest short range guidance keeps the vast
majority of the precip west and northwest of the STL Metro area
through the night. Not to say there couldn`t be some isolated to
scattered showers/t-storms just about anywhere after 06Z, but it
may not be worth the likely to categorical PoPs currently in the
forecast. The RAP focuses the low level jet over northeast MO into
central IL. This pushes the baroclinic zone north and while the
low level jet continues to be relatively strong across the entire
area, temperature/moisture advection becomes almost neutral for
the majority of the area. Will keep likely-categorical PoPs over
northern sections tonight near the baroclinic zone and the nose of
the low level jet. Further south, will start with just low
chance/slight chance and trend slowly upward through the night as
the shortwave approaches.
Carney
&&
.SHORT TERM: (Through Late Tonight)
Issued at 253 PM CST Wed Feb 19 2014
Main concerns tonight are the potential for localized flooding and
that a few thunderstorms could produce some hail near severe
limits. Showers and scattered thunderstorms have already begun to
develop over southeast Kansas this afternoon in a band of strong
moisture convergence that extends from the Central Plains into the
Mid South. The RAP shows this moisture convergence moving into
central Missouri by 00Z, which will then spreads northeast across the
CWA during the evening. Large scale ascent will increase across the
CWA tonight with the approach of the upper trough. At the same
time, the instability will also increase through the night as lapse
rates steepens with the approach of the upper trough in a highly
sheared environment. Overall coverage with any severe storms
capable of producing quarter size hail between 06-12Z is expected to
be limited in coverage over parts of central, northeast and east
central Missouri as well as adjacent sections of Illinois. A flood
watch will go into effect at midnight tonight where we expect
thunderstorms to move over the remaining snowpack. The ground is
frozen in these areas and streams and area rivers have had problems
with ice jams that could cause some localized flooding. The NMM and
NSSL WRF/GFS simulated reflectivity are similar to going forecast
which already have high chances for showers and thunderstorms this
evening across central and northeast Missouri and west central
Illinois, that then spreads southeast across the rest of the CWA
overnight.
Britt
.LONG TERM: (Thursday through Next Wednesday)
Issued at 253 PM CST Wed Feb 19 2014
Deepening surface low to lift northeast into southeastern Iowa by
18z Thursday, then into Great Lakes region by 06z Friday. In the
meantime, associated cold front to rapidly slide east through
forecast area with another round of showers and thunderstorms on
Thursday. Some of the storms could be strong with isolated severe
storms not out of the question but best chances will be east and
southeast of forecast area. Heaviest rains continue to be in an
axis from central through northeast MO and into west central IL.
Flood watch for portions of central/northeast MO and west central IL,
where there is still snow cover, to remain in effect until 00z
Friday. As for temperatures, will warm up into the mid 40s to
upper 60s by midday, then temperatures to fall through the
afternoon hours as cold front exits region. Another issue to deal
with will be the winds. Winds to pickup from the south ahead of
cold front then veer to the west and increase even more, between
15 and 25 mph with gusts near 35-40 mph at times. At this time no
wind advisory needed, but will need to keep an eye out on future
model runs to see if one will be needed.
Precipitation to move out of forecast area by 00z Friday with winds
gradually diminishing and skies clearing out. Lows will be near
normal in the mid 20s to low 30s.
On Friday, weak surface ridge to build in with winds becoming
southwesterly once again ahead of a weak cold front. Highs will
range from the upper 40s northeast to the upper 50s southwest.
As front slides through late Friday afternoon and Friday night,
energy to remain just north and northeast of forecast area, so
should see dry conditions. Did keep silent slight chance pops over
northeast MO and west central IL on Friday where some light
snow/light rain may be possible, but confidence is low right now.
By Saturday, surface ridge to build back in with cooler conditions
expected. Highs will only be in the upper 30s to mid 50s, but still
near normal for this time of year.
Beyond that, another weak shortwave to approach region Saturday
night, but confidence is low on any precipitation. So kept silent
slight chance pops for portions of forecast area for now. Lows
Saturday night will range from near 20 far north to the low 30s
far south. Dry and colder weather expected Sunday and Sunday night
with highs in the low 30s to mid 40s and lows in the upper teens
to mid 20s.
Next chance for precipitation will be Monday and Monday night,
though best chances will be over northern MO and northern half of
IL, so adjusted pops accordingly. With colder air moving in, the
precipitation will be in the form of light snow with this system.
Colder weather to persist through mid week with highs in the mid 20s
to low 40s each day and lows in the teens to low 20s.
Byrd
&&
.AVIATION: (For the 00z TAFs through 00z Thursday Evening)
Issued at 549 PM CST Wed Feb 19 2014
Several concerns for this TAF period. First is LLWS after 06z at
KSUS/KCPS due to a developing LLJ. Next concern is scattered
thunderstorms overnight ahead of a strong storm system. After a
brief break in the precipitation, additional thunderstorms are
anticipated ahead of the system`s cold front. These storms will
eventually congeal into a line, but there is still some
uncertainty regarding the timing and location. Strong WSW winds
will occur behind the cold front.
Specifics for KSTL: Several concerns for this TAF period. First is
LLWS after 06z due to a developing LLJ. Next concern is scattered
thunderstorms overnight ahead of a strong storm system. After a
brief break in the precipitation, additional thunderstorms are
anticipated ahead of the system`s cold front. These storms will
eventually congeal into a line, but there is still some
uncertainty regarding the timing and location. Strong WSW winds
will occur behind the cold front during the afternoon.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FLOOD WATCH from Midnight CST tonight through Thursday afternoon
FOR Audrain MO-Boone MO-Knox MO-Lewis MO-Marion MO-Monroe
MO-Pike MO-Ralls MO-Shelby MO.
IL...FLOOD WATCH from Midnight CST tonight through Thursday afternoon
FOR Adams IL-Brown IL-Greene IL-Macoupin IL-Montgomery IL-
Pike IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
655 PM CST Wed Feb 19 2014
.SHORT TERM: (Through Late Tonight)
Issued at 253 PM CST Wed Feb 19 2014
Main concerns tonight are the potential for localized flooding and
that a few thunderstorms could produce some hail near severe
limits. Showers and scattered thunderstorms have already begun to
develop over southeast Kansas this afternoon in a band of strong
moisture convergence that extends from the Central Plains into the
Mid South. The RAP shows this moisture convergence moving into
central Missouri by 00Z, which will then spreads northeast across the
CWA during the evening. Large scale ascent will increase across the
CWA tonight with the approach of the upper trough. At the same
time, the instability will also increase through the night as lapse
rates steepens with the approach of the upper trough in a highly
sheared environment. Overall coverage with any severe storms
capable of producing quarter size hail between 06-12Z is expected to
be limited in coverage over parts of central, northeast and east
central Missouri as well as adjacent sections of Illinois. A flood
watch will go into effect at midnight tonight where we expect
thunderstorms to move over the remaining snowpack. The ground is
frozen in these areas and streams and area rivers have had problems
with ice jams that could cause some localized flooding. The NMM and
NSSL WRF/GFS simulated reflectivity are similar to going forecast
which already have high chances for showers and thunderstorms this
evening across central and northeast Missouri and west central
Illinois, that then spreads southeast across the rest of the CWA
overnight.
Britt
.LONG TERM: (Thursday through Next Wednesday)
Issued at 253 PM CST Wed Feb 19 2014
Deepening surface low to lift northeast into southeastern Iowa by
18z Thursday, then into Great Lakes region by 06z Friday. In the
meantime, associated cold front to rapidly slide east through
forecast area with another round of showers and thunderstorms on
Thursday. Some of the storms could be strong with isolated severe
storms not out of the question but best chances will be east and
southeast of forecast area. Heaviest rains continue to be in an
axis from central through northeast MO and into west central IL.
Flood watch for portions of central/northeast MO and west central IL,
where there is still snow cover, to remain in effect until 00z
Friday. As for temperatures, will warm up into the mid 40s to
upper 60s by midday, then temperatures to fall through the
afternoon hours as cold front exits region. Another issue to deal
with will be the winds. Winds to pickup from the south ahead of
cold front then veer to the west and increase even more, between
15 and 25 mph with gusts near 35-40 mph at times. At this time no
wind advisory needed, but will need to keep an eye out on future
model runs to see if one will be needed.
Precipitation to move out of forecast area by 00z Friday with winds
gradually diminishing and skies clearing out. Lows will be near
normal in the mid 20s to low 30s.
On Friday, weak surface ridge to build in with winds becoming
southwesterly once again ahead of a weak cold front. Highs will
range from the upper 40s northeast to the upper 50s southwest.
As front slides through late Friday afternoon and Friday night,
energy to remain just north and northeast of forecast area, so
should see dry conditions. Did keep silent slight chance pops over
northeast MO and west central IL on Friday where some light
snow/light rain may be possible, but confidence is low right now.
By Saturday, surface ridge to build back in with cooler conditions
expected. Highs will only be in the upper 30s to mid 50s, but still
near normal for this time of year.
Beyond that, another weak shortwave to approach region Saturday
night, but confidence is low on any precipitation. So kept silent
slight chance pops for portions of forecast area for now. Lows
Saturday night will range from near 20 far north to the low 30s
far south. Dry and colder weather expected Sunday and Sunday night
with highs in the low 30s to mid 40s and lows in the upper teens
to mid 20s.
Next chance for precipitation will be Monday and Monday night,
though best chances will be over northern MO and northern half of
IL, so adjusted pops accordingly. With colder air moving in, the
precipitation will be in the form of light snow with this system.
Colder weather to persist through mid week with highs in the mid 20s
to low 40s each day and lows in the teens to low 20s.
Byrd
&&
.AVIATION: (For the 00z TAFs through 00z Thursday Evening)
Issued at 549 PM CST Wed Feb 19 2014
Several concerns for this TAF period. First is LLWS after 06z at
KSUS/KCPS due to a developing LLJ. Next concern is scattered
thunderstorms overnight ahead of a strong storm system. After a
brief break in the precipitation, additional thunderstorms are
anticipated ahead of the system`s cold front. These storms will
eventually congeal into a line, but there is still some
uncertainty regarding the timing and location. Strong WSW winds
will occur behind the cold front.
Specifics for KSTL: Several concerns for this TAF period. First is
LLWS after 06z due to a developing LLJ. Next concern is scattered
thunderstorms overnight ahead of a strong storm system. After a
brief break in the precipitation, additional thunderstorms are
anticipated ahead of the system`s cold front. These storms will
eventually congeal into a line, but there is still some
uncertainty regarding the timing and location. Strong WSW winds
will occur behind the cold front during the afternoon.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FLOOD WATCH from Midnight CST tonight through Thursday afternoon
FOR Audrain MO-Boone MO-Knox MO-Lewis MO-Marion MO-Monroe
MO-Pike MO-Ralls MO-Shelby MO.
IL...FLOOD WATCH from Midnight CST tonight through Thursday afternoon
FOR Adams IL-Brown IL-Greene IL-Macoupin IL-Montgomery IL-
Pike IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
633 PM EST WED FEB 19 2014
.SYNOPSIS...
ANY EVENING LIGHT RAIN OR SNOW SHOWERS WILL COME TO AN END
OVERNIGHT AS LOW PRESSURE DEPARTS EAST INTO THE MARITIMES.
INCLEMENT WEATHER THEN RETURNS THURSDAY NIGHT INTO FRIDAY WITH
MIXED PRECIPITATION LIKELY AS A STORM SYSTEM PASSES THROUGH THE
GREAT LAKES. MILD TEMPERATURES CONTINUE INTO SATURDAY...WITH
CONIDITIONS TRENDING DRIER AND MUCH COLDER AGAIN BY EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 7 AM THURSDAY MORNING/...
AS OF 633 PM EST WEDNESDAY...MINOR UPDATES TO POPS/SKY/T/TD
DATASETS TO MATCH CURRENT OBSERVATIONAL TRENDS AS OF 600 PM. DID
OPT TO CHARACTERIZE REMAINDER OF BACK-END PCPN AS SHOWERY AS
OPPOPSED TO STEADIER SNOWS PER FAIRLY PALTRY RADAR RETURNS.
NONETHELESS...EXPECT AT LEAST SOME OF THIS ACTIVITY TO CONTINUE
THROUGH MIDNIGHT OR SO AS TAIL-END UPPER TROUGH SWINGS THROUGH THE
REGION. MESOSCALE MODELS ACTUALLY SHOWING SOME BRIEF SHSN
ENHANCEMENT ON THE VT SIDE OF THE CHVLY AND ALONG THE WRN SLOPES
INTO THE HIGHER TERRAIN OF THE GREENS IN THE 8-11 PM TIME FRAME AS
AFOREMENTIONED FEATURE SWINGS THROUGH AND FLOW REMAINS BLOCKED
BELOW 850 MB. TIME WILL TELL. REGARDLESS...LEFT POPS ALONE MAINLY
ADVERTISING HIGH CHC TO LIKELY VALUES THROUGH 11 PM OR SO BEFORE
CURTAILING THINGS FAIRLY SHARPLY LATER TONIGHT WITH SOME PARTIAL
CLEARING. ADDL ACCUMS LIGHT...MAINLY LESS THAN 1 INCH. WINDS TREND
LIGHT WESTERLY BEHIND THE TROUGH PASSAGE OVERNIGHT...BUT NO REAL
AIRMASS CHANGE SO TEMPS SHOULD HOLD SEASONABLY MILD IN THE 20S FOR
MOST SPOTS. HAVE A GREAT EVENING. PRIOR DISCUSSION FOLLOWS.
PRIOR DISCUSSION...
STEADY SNOW IS ENDING ACROSS CENTRAL/ERN VT LATE THIS AFTN AS
DEVELOPING SFC LOW ACROSS SERN MA TRACKS NEWD INTO THE GULF OF
MAINE. RECEIVED REPORTS OF 3-4" ACROSS RUTLAND AND WINDSOR
COUNTIES THIS AFTERNOON...SO LIKELY SOME LINGERING SLOW TRAVEL
THRU THE EVENING COMMUTE DUE TO SNOW COVERED ROADWAYS.
HIGH RESOLUTION MODELS CONTINUE TO INDICATE LINGERING FLURRY OR
LIGHT SNOW SHOWER ACTIVITY IN THE NRN ADIRONDACKS AND NRN GREEN
MTNS. THIS IS CONSISTENT WITH INCREASING TREND IN RADAR
REFLECTIVITY ACROSS ERN FRANKLIN VT/CHITTENDEN COUNTY DURING THE
PAST HOUR. MAY SEE LOCALIZED 1-2" AMTS ACROSS THE MTNS
THIS EVENING...WITH ACTIVITY DIMINISHING AFTER MIDNIGHT. PARTIAL
CLEARING IS EXPECTED BY DAYBREAK AREAWIDE AS SHORTWAVE RIDGE
BUILDS INTO NRN NY TOWARD 12Z WEDNESDAY. LOWS WILL BE ABOVE
AVERAGE TONIGHT AS AIR MASS CONTINUES TO MODERATE...AND CLOUDS
LIMIT RADIATIVE COOLING TO SOME EXTENT. LOOKING FOR LOWS GENERALLY
IN THE UPPER TEENS TO MID 20S...HIGHEST IN THE CHAMPLAIN VLY.
&&
.SHORT TERM /7 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 315 PM EST WEDNESDAY...QUIET AND MILD CONDITIONS THURSDAY.
SFC RIDGE AND SHORTWAVE RIDGING ALOFT WILL BISECT THE NORTH
COUNTRY AT 18Z. 850MB TEMPS MODERATE TO -1C TO -3C...AND THIS
SHOULD ALLOW SFC TEMPS TO RISE INTO UPPER 30S TO LOWER 40S. MOSTLY
SUNNY IN THE MORNING...BUT SHOULD SEE AN INCREASE IN MID-UPR LEVEL
CLOUD COVER DURING THE AFTN WITH ONSET OF ISENTROPIC ASCENT IN
ADVANCE OF NEXT FRONTAL SYSTEM.
RAPIDLY DEEPENING SFC CYCLONE (970MB BY 12Z FRIDAY) TRACKING NEWD
THRU THE CENTRAL GREAT LAKES THURSDAY NIGHT IS ASSOCIATED WITH A
LEADING WARM FRONT AND STRONG SLY LOW-LEVEL JET WHICH WILL BE
LIFTING THRU THE NORTH COUNTRY. THE 12Z NWP GUIDANCE IS A BIT
QUICKER WITH ONSET OF MIXED WINTRY PRECIPITATION ACROSS THE
REGION...WITH STRONG WAA BRINGING WIDESPREAD STRATIFORM PCPN INTO
THE AREA. PRECIPITATION WILL REACH THE ADIRONDACKS AND S-CENTRAL
VT BY MIDNIGHT...AND OVERSPREAD THE REMAINDER OF THE REGION DURING
THE PRE-DAWN HOURS. IT APPEARS A QUICK CHANGE FROM SNOW TO
SLEET/FREEZING RAIN IS LIKELY IN THE ADIRONDACKS...NRN ST. LAWRENCE
VALLEY...AND POINTS EAST OF THE GREEN MTNS DURING THE PRE-DAWN HRS
FRIDAY...LASTING INTO THE MORNING COMMUTE. IN THE CHAMPLAIN
VALLEY...WET SNOW TO MAINLY RAIN EXPECTED WITH LOCALLY ABOVE 32F
TEMPS. SFC TEMPS REMAIN 28-32F LONGEST EAST OF THE GREEN
MTNS...AND WITH TEMPS REACHING +4 TO +6C IN SOUNDING WARM "NOSE"
BETWEEN 850-800MB...THERMODYNAMIC PROFILES STRONGLY FAVOR PERIOD
OF FREEZING RAIN ACROSS CENTRAL/ERN VT. ICY ROAD CONDITIONS WITH
COLD GROUND CONDITIONS WILL MAKE FOR A HAZARDOUS MORNING COMMUTE
AWAY FROM THE CHAMPLAIN VALLEY...ESPECIALLY CENTRAL/ERN VT. A
WINTER WEATHER ADVISORY MAY EVENTUALLY BE REQUIRED AS WE GET
CLOSER TO THE EVENT. TOTAL ICE WILL GENERALLY REMAIN BELOW 0.2"
MAX...SO MAIN IMPACT WILL BE TO TRANSPORTATION. ANY SNOW/SLEET AT
THE START OF THE PRECIPITATION EVENT WILL AMOUNT TO 2" OR LESS.
SOME GUSTY DOWNSLOPE WINDS ARE ALSO POSSIBLE EARLY FRIDAY...SE
20-30 WITH GUSTS TO 40 MPH ALONG THE WRN SLOPES OF THE GREEN MTNS.
THIS WOULD MAINLY OCCUR BETWEEN 06-15Z FRIDAY. FOLLOWING COLD
FRONTAL PASSAGE...STEEP LOW-LEVEL LAPSE RATES AND CHANNELED FLOW
IN THE ST. LAWRENCE VALLEY WILL LIKELY YIELD SOME SW GUSTS 40-45
MPH. WINDS SHOULD NOT BE QUITE AS STRONG ELSEWHERE.
QPF AMTS EXPECTED TO RANGE FROM 0.4"-0.8"...HIGHEST IN THE
ADIRONDACKS WITH UPSLOPE FLOW AND INTO THE CENTRAL GREEN MTNS.
LOCAL SHADOWING AFFECTS IN THE CHAMPLAIN VALLEY WILL RESULT IN
TOTAL PRECIPITATION ON THE LOW END OF THE RANGE. DESPITE TEMPS
WELL INTO THE 40S TO NEAR 50F...NOT ANTICIPATING ANY SIGNIFICANT
HYDRO CONCERNS AS OUTLINED IN HYDRO SECTION BELOW.
CLEARING FRIDAY NIGHT WITH WLY FLOW. AIR MASS IS NOT PARTICULARLY
COLD IN THE WAKE OF THE COLD FRONT PER NAM/GFS THERMAL FIELDS.
KEPT LOWS GENERALLY IN THE 20S FOR FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 250 PM EST WEDNESDAY...LITTLE CHANGE FROM PREVIOUS COUPLE OF
FCSTS WITH REGARDS TO LARGE SCALE SYNOPTIC PATTERN WHICH SUPPORTS
DEEP FULL LATITUDE MID/UPPER LVL TROF DEVELOPING ACRS THE EASTERN
CONUS. THIS WL SUPPORT A TREND TWD BLW NORMAL TEMPS BY EARLY NEXT
WEEK...ALONG WITH BLW NORMAL CHCS FOR PRECIP. GIVEN THE POSITION
OF TROF AXIS AND SFC HIGH PRES...EXPECTING A FAST WESTERLY
CONFLUENT FLW ACRS OUR CWA...WITH NO INTERACTION OF SUB TROPICAL
MOISTURE INTO OUR REGION. THE COMBINATION OF S/W ENERGY IN THE FLW
ALOFT AND SFC TROFS EVERY COUPLE OF DAYS...WL RESULT IN MAINLY ON
AND OFF MTN SNOW SHOWERS THRU THE PERIOD...BUT ACCUMULATIONS WL BE
LIGHT. TEMPS WL START MUCH ABOVE NORMAL FOR SAT WITH PROGGED 925MB
TEMPS RANGING FROM -2C SLV TO +2C CT RIVER VALLEY...SUPPORTING L/M
30S MTNS L/M 40S VALLEYS...ESPECIALLY LWR CT RIVER VALLEY. BY
SUNDAY...925MB TEMPS FALL ANOTHER 3 TO 6 DEGREES SUPPORTING HIGHS
BACK INTO THE 20S MTNS TO 30S VALLEYS. THIS TREND OF COOLING LLVL
THERMAL PROFILES BY 3 TO 6 DEGREES A DAY CONTINUES FOR MONDAY INTO
TUESDAY...WITH EXPECTED HIGHS IN THE TEENS TO L/M20S ANTICIPATED.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
THROUGH 18Z THURSDAY...IFR CONDITIONS WL OCCUR AT RUT/MPV THRU 21Z
TODAY...WITH POTENTIAL IFR CIGS/VIS DEVELOPING AT SLK BY 23Z THIS
EVENING. CRNT RADAR SHOWS BAND OF MODERATE SNOW LIFTING ACRS
CENTRAL/SOUTHERN VT...IMPACTING MPV/RUT WITH VIS BLW 1SM. BASED ON
RAP13 AND HRRR MODEL PROGGED COMPOSITE REFLECTIVITY EXPECT THIS
ACTIVITY TO BE EAST OF OUR TAF SITES BY 21Z WITH MAINLY MVFR
CONDITIONS PREVAILING. AT SLK THINKING WEAK SFC TROF WL SHIFT THE
WINDS TO THE WEST/NORTHWEST THIS EVENING WITH LLVL CLOUDS AND
LIGHT SNOW DEVELOPING. THIS WL RESULT IN A PERIOD OF IFR
CONDITIONS AT SLK WITH VIS BLW 2SM AND CIGS BLW OVC 1000 FT.
ELSEWHERE...EXPECTING MAINLY VFR WITH BRIEF PERIODS OF MVFR AT
MSS/BTV THRU THIS EVENING. WEAK SFC RIDGE WITH VFR CONDITIONS WL
PREVAIL LATE TONIGHT INTO 18Z WEDS AT OUR TAF SITES.
OUTLOOK 18Z THURSDAY THROUGH SUNDAY...
VFR CONDITIONS WITH THICKENING CLOUDS THRU 00Z FRIDAY. SFC WARM
FRNT WL RESULT IN MIXED PRECIP DEVELOPING BY 06Z FRIDAY WITH SOME
ICE ACCUMULATION POSSIBLE AT MPV...ALONG WITH WIDESPREAD MVFR/IFR
CONDITIONS LIKELY BTWN 06Z-12Z FRIDAY. ANOTHER BAND OF MAINLY RAIN
SHOWERS OCCURS FRIDAY WITH MVFR CONDITIONS...WITH EXCEPTION OF IFR
POSSIBLE AT MSS/SLK/MPV. ALSO...WITH WARM TEMPS MOVING OVER
RELATIVELY COLD SFC TEMPS/SNOWPACK AREAS OF FOG/BR WL BE POSSIBLE
IN THE DEEPER PROTECTED VALLEY LOCATIONS OF VT/NY FRIDAY INTO
SATURDAY. STRONG LLVL JET WL RESULT IN AREAS OF LLVL WS ON
FRIDAY...ESPECIALLY AT MSS WITH NORTHEAST SFC WINDS AND SW WINDS
ALOFT AT 1500 FEET AND AT MPV WITH LIGHT SFC WINDS ANTICIPATED AND
STRONG 1000 AGL WINDS OF 45 TO 50 KNTS. GUSTY SE WINDS OF 30 TO 35
KNTS WL BE POSSIBLE AT RUTLAND ON FRIDAY MORNING...WHICH WL SHIFT
TO THE SOUTHWEST AND BECM GUSTY AT MSS/SLK/PBG/BTV DURING THE
AFTN/EVENING OF FRIDAY. OTHERWISE...DRY SLOT WL RESULT IN VFR
CONDITIONS DEVELOPING FRIDAY NIGHT AND PREVAILING INTO SUNDAY.
&&
.HYDROLOGY...
NO SIGNIFICANT HYDROLOGICAL ISSUES FORESEEN WITH BRIEF WARMUP
THURSDAY AND FRIDAY AS SNOWPACK IS NOT RIPE FOR RAPID SNOWMELT. MOST
OF THE EXPECTED PRECIPITATION FRIDAY (BASIN AVG AROUND 0.40"-0.70")
IS EXPECTED TO BE ABSORBED INTO THE SNOWPACK GIVEN CURRENT
CHARACTERISTICS OF SNOWPACK. THAWING DEGREE HOURS REACH NEAR 300
ACROSS A LIMITED AREA OF ADDISON/RUTLAND COUNTY AND IN ST. LAWRENCE
COUNTY NY...WHERE TEMPERATURES WILL APPROACH 48-50F FOR A TIME
FRIDAY. SHOULD ANY MINOR ICE JAMS DEVELOP FRIDAY OR FRIDAY
NIGHT...WILL LIKELY BE CONFINED TO RUTLAND/ADDISON/ST. LAWRENCE
COUNTIES...AND ON THE SMALLER RIVERS AND STREAMS. LOW PROBABILITY
OF ANY ICE JAM FLOODING AT THIS POINT...BUT WE WILL CONTINUE TO
MONITOR.
&&
.EQUIPMENT...
DAMAGED EQUIPMENT HAS RESULTED IN AN AUDIBLE HUM ON THE MOUNT
ASCUTNEY NOAA WEATHER RADIO BROADCAST (WXM-44). OUR TECHNICIANS
ARE AWARE OF THE PROBLEM AND WILL RESOLVE THE ISSUE AS QUICKLY AS
POSSIBLE. REPAIRS MAY INVOLVE COORDINATION AND ACCESS BY
TELCO...INCLUDING PARTS ACQUISITION. THIS MAY TAKE 1-2 DAYS TO
RESOLVE. IN THE MEANTIME...WE APOLOGIZE FOR ANY DIFFICULTIES IN
HEARING THE BROADCAST FROM MOUNT ASCUTNEY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG/BANACOS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
HYDROLOGY...BANACOS
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
534 PM EST TUE FEB 18 2014
.SYNOPSIS...
LIGHT SNOW WILL COME TO AN END THIS EVENING AS WEAK HIGH PRESSURE
BUILDS INTO THE REGION. ANOTHER ROUND OF VERY LIGHT SNOW OR
FLURRIES IS EXPECTED ACROSS THE AREA ON WEDNESDAY AS ADDITIONAL
WEAK LOW PRESSURE CROSSES THE REGION. A STRONGER STORM SYSTEM WILL
AFFECT THE AREA THURSDAY NIGHT INTO FRIDAY WITH MILDER
TEMPERATURES ALONG WITH A MIX OF WINTRY PRECIPITATION AND LOCALLY
GUSTY WINDS.
&&
.NEAR TERM /UNTIL 7 AM WEDNESDAY MORNING/...
AS OF 534 PM EST TUESDAY...FORECAST IN GOOD SHAPE AS WE HEAD INTO
THE EVENING HOURS. DID OPT TO CUT BACK ON POPS RATHER QUICKLY THIS
EVENING PER LATEST RAP PROGS WHICH APPEARS TO BE HANDLING CURRENT
SITUATION QUITE WELL BASED OFF RECENT RADAR TRENDS. THUS EXPECT
MOST SNOWFALL TO BE OVER IN MOST AREAS BY 8 PM IF NOT SOONER IN
THE CASE OF NORTHERN NEW YORK. TEMPERATURES STILL HOLDING IN THE
LOWER TO MID 20S IN MOST SPOTS AS OF THE 5 PM HOUR WITH ONLY A
SMALL DOWNWARD TREND OVERNIGHT DUE TO CONTINUED S/SW FLOW AND AT
LEAST SOME CLOUD COVER HERE AND THERE THROUGH THE NIGHT. PRIOR
DISCUSSION FOLLOWS. HAVE A GREAT EVENING.
PRIOR DISCUSSION...
PERIOD OF ACCUMULATING SNOW WILL CONTINUE THRU 23-00Z ASSOCIATED
WITH UPPER LOW...WHICH IS CURRENTLY MVG ENEWD ACROSS THE NRN
ADIRONDACKS AT 2030Z. ANTICIPATE ANOTHER 1-2" ACROSS NRN VT AND
NRN NY BEFORE ENDING. ATLANTIC MOISTURE ASSOCIATED WITH SECONDARY
LOW SPINNING UP ACROSS RI AND SERN MA NOT REALLY BEING TAPPED AT
THE MOMENT. THAT SAID...POTENTIAL STILL EXISTS FOR SOME
MOISTURE/UPSLOPE ENHANCEMENT ACROSS S-CENTRAL VT ALLOWING FOR
LOCALLY HIGHER SNOW TOTALS OF 3-6". ANTICIPATE THE HIGHEST SNOW
TOTALS ALONG THE ERN SLOPES OF THE GREEN MTNS FROM LUDLOW TO
BETHEL AND ACROSS THE SUMMITS. MAINTAINED WINTER WX ADVISORY FOR
RUTLAND/WINDSOR/ORANGE THRU 02Z. SNOW COVERED ROADS AREAWIDE AND
PERIODS OF 1/2 MILE VSBY WILL MAKE FOR SOME TRAVEL SLOWDOWNS
DURING THE EVENING COMMUTE...WITH SOMEWHAT WORSE CONDITIONS ACROSS
S-CENTRAL VT.
ANTICYCLONIC FLOW ALOFT AND NARROW SFC RIDGE AXIS BUILDS INTO NRN
NY BY 03Z AND ACROSS VT BY 06Z. THIS SHOULD RESULT IN SUBSIDENCE
AND QUICK END TO ACCUMULATING SNOW THIS EVENING. KEPT SOME CHANCE
POPS ACROSS FAR ERN VT THRU ABOUT MIDNIGHT. NAM/RAP MODEL RH
PROFILES SUGGEST SOME CLEARING OVERNIGHT WITHIN THE RIDGE AXIS.
WITH LIGHT SFC WINDS AND PARTIAL CLEARING...LOWS SHOULD DRO
&&
.SHORT TERM /7 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 346 PM EST TUESDAY...PROGRESSIVE UPPER FLOW PATTERN CONTINUES
ACROSS THE CENTRAL AND ERN CONUS. NEXT FAST-MOVING
TROUGH...CURRENTLY ACROSS THE UPPER MS VALLEY...IS EXPECTED TO
REACH THE ERN GREAT LAKES REGION BY 12Z WEDNESDAY...AND THEN THRU
THE NORTH COUNTRY BETWEEN 18-00Z. PERIOD OF MID-LEVEL UVV
TRANSLATES EWD ACROSS THE NORTH COUNTRY MIDDAY THRU LATE AFTERNOON
WEDNESDAY...BRINGING A PERIOD OF SNOW SHOWER ACTIVITY ACROSS THE
REGION. LOOKING FOR SUB-ADVISORY SNOWFALL ACCUMULATIONS...GENERALLY
1-3"...HIGHEST AWAY FROM THE CHAMPLAIN VALLEY (WHERE SOME LOCAL
SHADOWING EFFECTS APPEAR LIKELY). TROUGH PASSAGE AFTER 00Z SHOULD
BRING AN END TO THE SNOWFALL BY LATE EVENING FOR MOST SECTIONS.
ALSO...AIR MASS WILL CONTINUE TO MODERATE WEDNESDAY. DESPITE
MOSTLY CLOUDY TO CLOUDY CONDITIONS...HIGH TEMPERATURES WILL
GENERALLY REACH THE 33-37F. ABOVE FREEZING NEAR- SURFACE LAYER IS
MARGINAL FOR ANY VALLEY RAIN...WITH ABOVE FREEZING DEPTH GENERALLY
800-900 FT. WILL KEEP AS GENERALLY SNOW...BUT MAY SEE SOMEWHAT
LOWER VALLEY ACCUMULATIONS DUE TO WARMER SFC
CONDITIONS...ESPECIALLY ON PAVEMENT.
NEXT MOBILE SHORTWAVE RIDGE TRAVERSES THE REGION WEDNESDAY NIGHT
WITH GENERALLY DRY WEATHER CONDITIONS. VARIABLE CLOUDY CONDITIONS
EXPECTED...AND WILL HELP KEEP TEMPERATURES GENERALLY IN THE 20S FOR
OVERNIGHT LOWS WEDNESDAY NIGHT.
CONTINUED QUIET FOR THURSDAY. RIDGE AXIS SLIDES EAST OF THE CT RIVER
VALLEY AND WILL ALLOW FOR A DEVELOPING LIGHT (5-10 MPH) RETURN FLOW.
PARTLY SUNNY CONDITIONS ANTICIPATED BASED ON SOME HIGHER MID-UPR
LEVEL RH ACROSS THE REGION. 850MB TEMPS CLIMB TO NEAR 0C BY 00Z
FRIDAY. SHOULD SEE MOST LOCATIONS IN THE 37-42F RANGE FOR DAYTIME
HIGHS THURSDAY AFTN.
STRONGER/HIGH AMPLITUDE MID-LEVEL TROUGH ACROSS THE CENTRAL MS VALLEY
THURSDAY NIGHT RESULTS IN RAPIDLY DEEPENING LOW PRESSURE ACROSS THE
GREAT LAKES REGION (976MB PER 12Z GFS AT 06Z FRIDAY). STRONG SLY
LOW-LEVEL JET DEVELOPS DURING THURSDAY NIGHT...WITH 60KT AT 850MB BY
DAYBREAK FRIDAY ACROSS NRN NY AND EWD INTO THE CHAMPLAIN VALLEY.
STRONG WARM FRONTAL ASCENT WILL BRING STRATIFORM PRECIPITATION TO
THE REGION...ESPECIALLY AFTER MIDNIGHT THURSDAY NIGHT. A BIT OF
ELEVATED CAPE ALSO PRESENT IN NAM FORECAST SOUNDINGS AROUND 10-12Z
FRIDAY...SO MAY SEE SOME EMBEDDED CONVECTIVE ELEMENTS WITH HVY
PRECIPITATION. WILL CONTINUE TO SHOW 60-80 POPS AFTER 06Z. ABOVE
FREEZING TEMPS LIKELY IN THE CHAMPLAIN VALLEY. HOWEVER...IT APPEARS
BASED ON MODEL SOUNDINGS THAT TEMPS ELSEWHERE WILL BE BELOW FREEZING
NEAR THE SFC WITH FAVORABLE PROFILES FOR A PERIOD OF SLEET AND
POSSIBLE FREEZING RAIN. THIS MAY HAVE SOME TRAVEL IMPACT DURING THE
PRE-DAWN HRS INTO THE EARLY MORNING COMMUTE. WILL CONTINUE TO SHOW
MIXED PRECIPITATION IN THE FCST GRIDS. ALSO LOOKING AT LOCALLY
STRONG AND GUSTY WINDS...WITH SOUTH GUSTS 25-35 MPH...PERHAPS A BIT
STRONGER RIGHT ALONG THE WRN SLOPES OF THE GREEN MOUNTAINS WITH
DOWNSLOPE EFFECTS.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 315 PM EST TUESDAY...A CHANGEABLE WX PATTERN UPCOMING FROM
MID/UPPER LVL RIDGE ACRS THE EASTERN CONUS ON FRIDAY/SATURDAY
TO A DEEP TROF AND ARCTIC AIR BY EARLY NEXT WEEK. FCST CHALLENGE
ON FRIDAY WL BE PTYPE...WINDS...AND TEMPS...FOLLOWED BY TIMING OF
COOLING FOR FRIDAY NIGHT INTO SATURDAY. STILL SOME UNCERTAINTY ON
MAGNITUDE OF MID/UPPER LVL TROF NEXT WEEK AND AMOUNT OF LLVL CAA
ACRS OUR CWA.
BOTH GFS/NAM SHOW VERY STRONG 925MB TO 850MB WINDS OF 45 TO 65
KNOTS ON FRIDAY MORNING...WHICH WL RESULT IN STRONG LOCALIZED SE
DOWNSLOPE WINDS OF 30 TO 40 KNOTS. THESE WINDS WL QUICKLY SHIFT TO
THE SOUTHWEST AS FROPA OCCURS DURING THE LATE MORNING/EARLY AFTN
HRS...WITH STRONGEST PRES RISE COUPLET ACRS THE SLV. THINKING THIS
WL RESULT IN GUSTY SOUTHWEST WINDS ACRS THE SLV/DACKS BTWN 30 AND 40
KNOTS ON FRIDAY MIDDAY.
ALL MODELS AGREE ON PRECIP COMING IN TWO SEPARATE WAVES...FIRST
ASSOCIATED WITH WAA EARLY FRIDAY MORNING...FOLLOWED BY FROPA
PRECIP BTWN 12Z AND 21Z FRIDAY. THE PRECIP ASSOCIATED WITH THE
COLD FRNT WL BE A 2 TO 5 HR PRECIP EVENT WITH GENERAL QPF BTWN
0.25 AND 0.50" ACRS OUR CWA. EXPECTING SFC TEMPS TO BE MAINLY
ABOVE FREEZING WITH SFC FRNT...RESULTING IN RAIN...BUT SOME
POCKETS OF FREEZING RAIN WL BE POSSIBLE IN THE COLDER VALLEYS OF
CENTRAL/EASTERN VT...INCLUDING THE NEK ON FRIDAY. PROGGED 85H
TEMPS WARM BTWN 6C AND 8C PRIOR TO FROPA...SUGGESTING TEMPS WELL
INTO THE 40S...WITH EVEN A FEW L50S POSSIBLE AROUND RUTLAND AND IN
THE CANTON/POTSDAM AREAS ON FRIDAY MORNING. TEMPS ACRS THE HIGHER
TRRN WL COOL QUICKLY ON FRIDAY AFTN...WITH STRONG 85H CAA
DEVELOPING ON GUSTY WINDS.
SATURDAY-TUESDAY...TEMPS WL SLOWLY RETURN TO BLW NORMAL BY EARLY
NEXT WEEK AS MID/UPPER LVL TROF REDEVELOPS ACRS OUR CWA. GIVEN
SOUTHWEST FLW ALOFT ON SATURDAY AND PROGGED 85H TEMPS BTWN -4C AND
-6C...TEMPS SHOULD WARM INTO THE 40S WARMER VALLEYS AND MID 30S
MTNS/NEK. WARMEST TEMPS WL BE AROUND VSF DUE TO DOWNSLOPE WARMING
ON WESTERLY FLW. SECONDARY COLD FRNT ARRIVES ON SUNDAY...WITH
LATEST GFS SHOWING A RIBBON OF ENHANCED FGEN FORCING ALONG WITH
DEEPER 850 TO 500MB RH. HAVE INCLUDED CHC POPS FOR SAT NIGHT INTO
SUNDAY...BUT OVERALL QPF/SNOWFALL WL BE LIGHT. ADDITIONAL S/W
ENERGY AND ANOTHER FRNT PUSHES ACRS OUR CWA LATE SUNDAY INTO
MONDAY WITH ANOTHER SURGE OF COLDER TEMPS. PROGGED 85H TEMPS DROP
TO AROUND -20C BY 12Z MONDAY OFF BOTH THE GFS/ECMWF...SUPPORTING
HIGHS ONLY IN THE TEENS MTNS TO L/M 20S VALLEYS WITH ONLY A SLIGHT
CHC FOR MAINLY MTN SNOW SHOWERS. THE 6 TO 10 DAY OUTLOOK FROM CPC
SHOWS BLW NORMAL TEMPS AND PRECIP. AS ALWAYS THE DEPTH AND
POSITION OF THE MID/UPPER LVL TROF AXIS WL HAVE TO BE WATCHED
CLOSELY...ALONG WITH TIMING OF INDIVIDUAL S/W`S IN THE
NORTHERN/SOUTHERN STREAMS FOR NEXT WEEK AND DEVELOPMENT OF LOW
PRES ACRS THE EASTERN CONUS.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 18Z WEDNESDAY...SHORT TERM AVIATION FOCUS WL BE ON IFR
CONDITIONS ASSOCIATED WITH BAND OF LIGHT TO MODERATE SNOW LIFTING
ACRS OUR TAF SITES THIS AFTN. CRNT RADAR AND OBS SHOW VIS BTWN
1/2SM AND 3SM IN THIS BAND OF SNOW...WHICH WL CONT TO IMPACT OUR
TAF SITES THRU 22Z THIS EVENING...BEFORE DISSIPATING.
ALSO...EXPECT SOME IFR CIGS AT SLK/MSS TO DEVELOP WITH BASES BTWN
600 AND 900 FEET THIS AFTN...THEN REDEVELOP AGAIN BTWN 02Z AND 06Z
THIS EVENING. GUSTY SOUTHERLY WINDS AT 15 TO 20 KNOTS WL DISSIPATE
AS HEAVIER PRECIP ARRIVES THIS AFTN AND GENERALLY SHIFT TO THE
SOUTHWEST AT 5 TO 10 KNOTS...EXCEPT NORTHEAST AT AROUND 10 KNOTS
AT MSS. SNOW WL QUICKLY END BY 00Z TONIGHT WITH GENERALLY VFR
CONDITIONS DEVELOPING BY 04Z...WITH EXCEPT OF LINGERING MVFR AT
SLK/MSS/MPV. NEXT WARM FRNT WITH LIGHT SNOW ACTIVITY APPROACHES
OUR TAF SITES BY 16Z WEDS.
OUTLOOK 18Z WEDNESDAY THROUGH SATURDAY...
WARM FRONT AND ASSOCIATED MOISTURE/LIFT WL PRODUCE A BAND OF LIGHT
SNOW BTWN 18Z WEDS AND 00Z THURS WITH MVFR TO OCCASIONAL IFR
LIKELY...ESPECIALLY AT MPV/SLK/MSS. WEAK SFC HIGH PRES WITH VFR
CONDITIONS PREVAIL FROM 00Z THURS INTO 00Z FRIDAY. NEXT WARM FRNT
WITH BAND OF LIGHT TO MODERATE MIXED PRECIP ARRIVES AFT 06Z
FRIDAY UNTIL 15Z FRIDAY WITH IFR/MVFR CONDITIONS...AND SOME ICING
POSSIBLE AT MPV/MSS. ALSO...LLVL WIND SHEAR IS LIKELY AFT 06Z
FRIDAY...ASSOCIATED WITH 925MB TO 850MB JET OF 45 TO 65 KNOTS AND
LIMITED MIXING. SOUTHERLY WINDS WL SHIFT TO THE SOUTHWEST BEHIND
FROPA AFT 18Z FRIDAY. IN ADDITION...FROPA WL BE ASSOCIATED WITH A
BRIEF 1 TO 3 HR WINDOW OF LIGHT TO MODERATE RAIN ON
FRIDAY...BEFORE DRIER AND BREEZY WINDS DEVELOP ON SATURDAY WITH
SOME LEFTOVER MTN SNOW SHOWERS.
&&
.EQUIPMENT...
DAMAGED EQUIPMENT HAS RESULTED IN AN AUDIBLE HUM ON THE MOUNT
ASCUTNEY NOAA WEATHER RADIO BROADCAST (WXM-44). OUR TECHNICIANS
ARE AWARE OF THE PROBLEM AND WILL RESOLVE THE ISSUE AS QUICKLY AS
POSSIBLE. REPAIRS MAY INVOLVE COORDINATION AND ACCESS BY
TELCO...INCLUDING PARTS ACQUISITION. THIS MAY TAKE 1-2 DAYS TO
RESOLVE. IN THE MEANTIME...WE APOLOGIZE FOR ANY DIFFICULTIES IN
HEARING THE BROADCAST FROM MOUNT ASCUTNEY.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER WEATHER ADVISORY UNTIL 9 PM EST THIS EVENING FOR
VTZ010>012-019.
NY...NONE.
&&
$$
SYNOPSIS...JMG
NEAR TERM...JMG/BANACOS
SHORT TERM...BANACOS
LONG TERM...TABER
AVIATION...TABER
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS BUFFALO NY
735 AM EST TUE FEB 18 2014
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL LIFT NORTH OF LAKE ONTARIO TODAY WITH
SCATTERED SNOWFALL AND GUSTY WINDS. THE LOW WILL SHIFT TO THE NEW
ENGLAND COAST THIS AFTERNOON WITH SNOW AND GUSTY WINDS TAPERING OFF.
TEMPERATURES WILL WARM ABOVE FREEZING WEDNESDAY...WITH THE WARMING
TREND CONTINUING THROUGH THE END OF THE WEEK AS A WARM FRONT LIFTS
NORTH ACROSS THE REGION. THE MILD WEATHER WILL COME TO AN END NEXT
WEEKEND WITH THE PASSAGE OF A STRONG COLD FRONT AND A RETURN TO MORE
WINTER-LIKE CONDITIONS.
&&
.NEAR TERM /THROUGH TONIGHT/...
A DEEP MID LEVEL CUT OFF LOW IS VERTICALLY STACKED ABOVE A STRONG
AREA OF LOW PRESSURE CENTERED OVER THE WESTERN END OF LAKE ONTARIO
AT 12Z WITH A COLD FRONT EXTENDING SOUTH ACROSS THE EASTERN END OF
LAKE ERIE AND THE WESTERN SOUTHERN TIER JUST WEST OF BUFFALO.
AREA RADARS SHOW A WIDE BAND OF SNOW ORIENTED JUST AHEAD OF THE COLD
FRONT ACROSS WESTERN NEW YORK. FURTHER EAST A SECOND BAND OF SNOW IS
LIFTING NORTH ACROSS THE NORTH COUNTY ALONG A WEAK WARM FRONT
EXTENDING EAST ACROSS LAKE ONTARIO TO NORTH OF SYRACUSE. ANOTHER
ROUND OF GUSTY...SUB ADVISORY...WINDS HAS WORKED ACROSS WESTERN NY
AS COLD AIR MIXES DOWN ALONG THE COLD FRONT. THESE WINDS ARE
CREATING BLOWING SNOW WITH REDUCED VISIBILITIES THIS MORNING. HAVE
DROPPED THE WIND ADVISORY AS THE STRONGEST WINDS HAVE SHIFTED EAST
OF THE FORECAST AREA.
THROUGH TODAY THE STORM SYSTEM WILL LIFT NORTH OF LAKE ONTARIO BY
NOON THEN AS THE BASE OF THE NEGATIVELY TILTING MID LEVEL TROUGH
REACHES THE EAST COAST THE SURFACE LOW WILL TRANSFER OFF THE NY/NJ
COAST THIS AFTERNOON. AS THIS WHOLE PROCESS OCCURS...MESOSCALE
MODELS INCLUDING THE WELL PERFORMING HRRR SHOW THE BAND OF SNOW
CURRENTLY OVER WESTERN NEW YORK WILL SHIFT EAST TO CENTRAL NEW YORK
FOR THE AFTERNOON. USED A BLEND OF MESOSCALE MODEL QPF WITH THE
LATEST UPDATE WHICH CAPTURES THE MESOSCALE ENHANCEMENT ORIENTATION
AND TIMING VERY WELL. OVERALL ONLY A GENERAL COATING TO AN INCH CAN
BE EXPECTED ACROSS MUCH OF THE NIAGARA FRONTIER...GENESEE VALLEY AND
FINGER LAKES. HIGHER SNOW TOTALS OF 2-3 INCHES LOOK TO OCCUR ACROSS
THE WESTERN SOUTHERN TIER AND 2-4 INCHES ACROSS THE TUG HILL
ASSOCIATED WITH THE ENHANCEMENT OF OROGRAPHIC LIFTING OVER THE
HIGHER TERRAIN OF THOSE LOCATIONS.
TONIGHT THE STORM SYSTEM WILL NORTH JUST OFF THE NEW ENGLAND COAST
WITH A BRIEF AREA OF RIDGING SHIFTING ACROSS OUR REGION. THIS SHOULD
PROVIDE MOST OF THE OVERNIGHT WITH FAIR WEATHER AND A LULL IN THE
GUSTY WINDS AND EVEN SOME BREAKS IN THE CLOUDS POSSIBLE. FURTHER
UPSTREAM ANOTHER STORM SYSTEM WILL SHIFT NORTH OF THE UPPER GREAT
LAKES WITH ITS COLD FRONT SHIFTING JUST TO THE DOORSTEP OF WESTERN
NEW YORK. THIS FRONT WILL BRING A CHANCE OF SOME MORE LIGHT SNOW
LATE OVERNIGHT TOWARD DAYBREAK WEDNESDAY BUT MOISTURE AND LIFT LOOK
TO BE VERY LIMITED SO ANY SNOW THAT DOES ARRIVE WILL BE VERY LIGHT.
SOUTHERLY WINDS WILL ALSO INCREASE AGAIN HELPING TEMPERATURES TO
RISE OVERNIGHT FROM THE MID 20S TOWARD THE LOW 30S.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
THEN LATTER HALF OF THE WEEK WILL REMAIN AN UNSETTLED PERIOD FOR THE
LOWER GREAT LAKES THANKS TO A VERY ACTIVE JET STREAM THAT WILL
REMAIN DRAPED ACROSS THE CONTIGUOUS UNITED STATES. A SHORTWAVE
EMBEDDED WITHIN THIS FLOW WILL CROSS THE REGION DURING THE DAY
WEDNESDAY BRINGING A CHANCE OF SNOW SHOWERS TO WESTERN AND NORTH
CENTRAL NEW YORK. AT THIS POINT IT APPEARS THAT THE STRONGEST PVA
WILL BE LOCATED WELL TO OUR SOUTH ACROSS PENNSYLVANIA WHILE THE MAIN
UPPER LOW AND SURFACE LOW WILL REMAIN WELL TO OUR NORTH IN THE
VICINITY OF JAMES BAY. WITH THE FORECAST AREA CAUGHT IN A ZONE OF
WEAKER FORCING IN BETWEEN THESE STRONGER FEATURES...AM THINKING THAT
WE WILL SEE SCATTERED RAIN/SNOW SHOWERS AT BEST WITH THE EXCEPTION
BEING ACROSS THE NORTH COUNTRY WHERE UPSLOPE FLOW SHOULD ENHANCE
ACTIVITY ENOUGH TO WARRANT LIKELY POPS.
TEMPERATURES WILL BE QUITE MILD AS COMPARED TO THE RECENT COLD
WEATHER THANKS TO BRISK SOUTHERLY FLOW AND WARM ADVECTION THAT WILL
PUSH TEMPS INTO THE UPPER 30S TO NEAR 40. READINGS WILL FALL BACK
INTO THE 20S WEDNESDAY NIGHT HOWEVER AS THE UPPER LEVEL TROUGH AND
ASSOCIATED WEAK SURFACE COLD FRONT SLIDES ACROSS THE REGION.
HIGH PRESSURE WILL TRAVERSE THE LOWER GREAT LAKES WEDNESDAY NIGHT
AND QUICKLY SLIDE TO THE EAST COAST THURSDAY. THIS WILL SET THE
STAGE FOR THE REAL WARMUP THAT WILL BEGIN ON THURSDAY AS RETURN FLOW
DEVELOPS BETWEEN THE HIGH MOVING OFF THE EAST COAST AND A LOW
PRESSURE SYSTEM MOVING OUT OF THE GREAT PLAINS TO THE MISSISSIPPI
VALLEY. LATEST MODEL RUNS HAVE SLOWED THE PROGRESSION OF THIS SYSTEM
CONSIDERABLY AND AS SUCH HAVE BACKED OFF THURSDAY/S HIGHS A FEW
DEGREES AS THE WARM FRONT WILL BE A LITTLE SLOWER TO ARRIVE THAN
PREVIOUSLY INDICATED. WHILE 50 IS NOT LIKELY TO BE ATTAINED
THURSDAY...LOW TO MID 40S THAT ARE NO EXPECTED WILL STILL FEEL QUITE
BALMY COMPARED TO THE RECENT COLD.
AS MENTIONED ABOVE...WITH THE LATEST GFS/ECMWF MODEL RUNS IN GOOD
AGREEMENT IN SLOWING THE PROGRESSION OF THE DEEPENING LOW OUT OF
THE MISSISSIPPI VALLEY...THE EXPECTED WARM FRONTAL PRECIP IS NOW NOT
EXPECTED TO DEVELOP ACROSS WESTERN NEW YORK UNTIL THURSDAY EVENING.
IT IS WORTH NOTING THAT THE NAM IS DEFINITELY A FAST OUTLIER
REGARDING THE SPEED OF THIS SYSTEM. STRONG WINDS WILL BE POSSIBLE
ACROSS THE HILLTOPS AND TYPICAL DOWNSLOPE AREAS AS A VERY STRONG LOW
LEVEL JET WILL PUSH ACROSS THE REGION AHEAD OF THE APPROACHING COLD
FRONT THAT WILL LIKELY BE PUSHING INTO WESTERN NEW YORK LATE
THURSDAY NIGHT...BRINGING HEAVY RAIN AND STRONG WINDS. AT THIS POINT
THE INSTABILITY PARAMETERS DO NOT APPEAR TO BE ENOUGH TO SUPPORT
THUNDER...HOWEVER GIVEN THE VERY STRONG DYNAMICS ASSOCIATED WITH
THIS SYSTEM...A SQUALL LINE IS NOT OUT OF THE QUESTION AND THE
POTENTIAL FOR DAMAGING WINDS ACCOMPANYING SUCH A SQUALL LINE WILL
NEED TO BE MONITORED CAREFULLY.
AS THE TIMING OF THE WARM FRONTAL PASSAGE AND SUBSEQUENT INCREASE IN
TEMPERATURES AND DEWPOINTS HAS SLOWED UP...SO HAS THE TIMING OF THE
FLOOD POTENTIAL. WHILE TEMPERATURES WILL CLIMB INTO THE LOWER 40S BY
THURSDAY AFTERNOON...DEWPOINTS ARE NOT EXPECTED TO CLIMB ABOVE
FREEZING UNTIL AT LEAST THURSDAY EVENING. HOWEVER ONCE THIS
OCCURS...THE MELTING OF THE SNOWPACK WILL BEGIN IN EARNEST WITH THE
INCREASING WINDS AND ANY RAIN SHOWERS ACCOMPANYING THE WARM FRONT
AND IN PARTICULAR THE POTENTIALLY HEAVY RAINS ALONG/AHEAD OF THE
COLD FRONT ACCELERATING THE MELT OFF AND INCREASING THE FLOOD
POTENTIAL FROM LATE THURSDAY NIGHT ONWARDS.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
CONCERN THIS PERIOD WILL COME IN THE THURSDAY AND FRIDAY TIME FRAME
WHEN WE SHIFT TO A SHARP WARMING TREND AND THE POTENTIAL FOR
SIGNIFICANT RAINFALL WHICH WILL LEAD TO AN INCREASED FLOOD
POTENTIAL.
MOST OF THE GUIDANCE SUGGESTING TWO DISTINCT EASTERN PACIFIC WAVES
PHASING ACROSS THE UPPER MIDWEST/NORTHERN GREAT LAKES...PROMOTING
STRONG CYCLOGENESIS ACROSS THE WESTERN GREAT LAKES THURSDAY/THURSDAY
NIGHT. THIS PATTERN WILL LIKELY PROMOTE STRONG LOW LEVEL THETA E
ADVECTION/MOISTURE TRANSPORT NORTHEASTWARD INTO THE LOWER GREAT
LAKES BY THURSDAY AFTERNOON. INITIAL CHANCES FOR PRECIPITATION LOOK
TO BE THURSDAY AFTERNOON. PROFILES BY THIS TIME LOOK TO BE WARM
ENOUGH TO SUPPORT RAIN...ALTHOUGH IF PRECIPITATION OCCURS A BIT
SOONER THERE MAY BE A BRIEF PERIOD OF SNOW OR FREEZING RAIN AT THE
IMMEDIATE ONSET. HOWEVER...FEEL ANY MIXED PRECIPITATION WILL BE VERY
SHORT LIVED AS STRENGTH OF LOW LEVEL ADVECTION WILL EASILY OVERWHELM
PROFILES OVER TO LIQUID PRECIPITATION.
AFTER THIS INITIAL WARM/MOIST ADVECTIVE SURGE THURSDAY AFTERNOON THE
FOCUS WILL TURN TOWARD THE POTENTIAL FOR ADDITIONAL PRECIPITATION
THURSDAY NIGHT INTO EARLY FRIDAY. DEPENDING ON THE EXACT EVOLUTION
OF THE PATTERN WITH REGARDS TO THE DEEPENING OF THE WESTERN GREAT
LAKES STORM...THE ASSOCIATED POWERFUL COLD FRONT SHOULD SWEEP
THROUGH THE AREA QUICKLY LATE THURSDAY NIGHT OR EARLY FRIDAY.
THE PRECIPITATION AHEAD AND ESPECIALLY ALONG THE FRONTAL ZONE WILL
LIKELY HAVE SOME CONVECTIVE NATURE TO IT. SOME AMOUNT OF UNCERTAINTY
EXISTS MAINLY WITH THE DEGREE OF INSTABILITY BEING THE LIMITING
FACTOR...BUT EMBEDDED THUNDERSTORM THREAT WILL BE POSSIBLE WITH THE
FRONTAL PASSAGE. STRENGTH OF WIND FIELDS ALOFT MAY SUGGEST THE
POTENTIAL FOR DAMAGING WINDS IF AN ORGANIZED CONVECTIVE LINE CAN
DEVELOP.
RAINFALL AMOUNTS DURING THIS TIME FRAME ARE ALSO A CONCERN...
ESPECIALLY IF ANY ENHANCED CONVECTIVE RAINFALL OCCURS. THE FLOOD
POTENTIAL CERTAINLY WILL BE INCREASED NOT ONLY FROM THE RAINFALL AND
WARM TEMPERATURES...BUT ALSO WITH EXPECTED SURFACE DEWPOINTS RISING
INTO THE UPPER 30S OR EVEN HIGHER WHICH WILL GREATLY ACCELERATE
SNOWMELT. FOR THESE REASONS A FLOOD WATCH HAS BEEN ISSUED FOR THE
ENTIRE AREA STARTING THURSDAY NIGHT. IN ADDITION...LOCALLY DENSE FOG
COULD BE AN ISSUE WITH DEWPOINTS THIS HIGH WORKING OVER THE FROZEN
GROUND.
ONCE THE COLD FRONT CROSSES THE AREA FRIDAY...THE COLDER AND DRIER
AIR ADVECTING IN ITS WAKE WILL PROVIDE SOME RELIEF TO THE RUNOFF
SITUATION...BUT I WOULD EXPECT ANY FLOODING PROBLEMS WHICH DO
DEVELOP TO BE ONGOING DURING THE DAY FRIDAY...BUT MUCH OF THIS WILL
DEPEND ON EXACT RAINFALL AMOUNTS FROM THURSDAY INTO EARLY FRIDAY AND
TEMPERATURE AND DEWPOINT TRENDS.
LOWER CONFIDENCE FORECAST BEYOND THIS POINT AS SMALLER SCALE WAVES
WILL BE IMPACTING THE AREA FOR THE WEEKEND AND EARLY NEXT WEEK...
WITH THE POTENTIAL FOR A SERIES OF LOW LEVEL AMPLITUDE CLIPPER
SYSTEMS THROUGH THIS PERIOD. THERE IS SOME BETTER MODEL SUPPORT
SHOWING REINFORCING COLDER AIR INTO THE LOWER LAKES BY EARLY NEXT
WEEK WHICH WOULD BE MORE SUPPORTIVE OF LAKE EFFECT/ENHANCED SNOWS IN
A NORTHWEST FLOW REGIME. THERE MAY EVEN BE SOME LAKE RESPONSE ISSUES
OFF LAKE ERIE DEPENDING UPON HOW MUCH OPEN WATER CAN DEVELOP FROM
THE INCOMING MILDER AIRMASS.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
WIDESPREAD IFR CONDITIONS IN SNOW AND BLSN THIS MORNING ACROSS
WESTERN NEW YORK ASSOCIATED WITH SNOW FALLING ALONG A COLD FRONT
WHICH IS SWEEPING EAST ACROSS NEW YORK WITH SOME GUSTY WINDS. THESE
CONDITIONS WILL SHIFT EAST THROUGH THE MORNING TO KROC AND KART.
WESTERLY WIND GUSTS UP TO 35 KNOTS ARE ALSO IMPACTING THE REGION AS
COLD AIR MIXES DOWN TO THE SURFACE BEHIND THE COLD FRONT.
THE SNOW WILL TAPER OFF FROM WEST TO EAST THIS AFTERNOON
AS THE SURFACE LOW AND UPPER LEVEL SUPPORT TRANSFER TO THE NEW
ENGLAND COAST. EXPECT CONDITIONS TO IMPROVE TO VFR ACROSS MUCH OF
THE REGION BY THIS EVENING. VFR WILL BE IN PLACE THROUGH MUCH OF THE
NIGHT THEN ANOTHER COLD FRONT WILL APPROACH WESTERN NEW YORK LATE
TONIGHT FROM THE WEST WITH A 50 KNOT LOW LEVEL JET AHEAD OF IT. THIS
WILL BRING ANOTHER ROUND OF LLWS BY 08-10Z.
OUTLOOK...
WEDNESDAY...MAINLY VFR WITH A CHANCE OF RAIN/SNOW SHOWERS.
THURSDAY...MVFR WITH RAIN SHOWERS LIKELY.
FRIDAY...MAINLY VFR WITH A CHANCE OF RAIN SHOWERS.
SATURDAY...VFR.
&&
.MARINE...
SOUTHERLY TO SOUTHWESTERLY WINDS IN PLACE THIS MORNING ACROSS THE
REGION AS A LOW PRESSURE AREA SHIFTS NORTH OF LAKE ONTARIO. GUSTY
WINDS ARE REACHING INTO SMALL CRAFT ADVISORY RANGE...ALTHOUGH
OFFSHORE FLOW WILL LIMIT WAVE HEIGHT. SOUTHWEST WINDS ALONG THE LAKE
ERIE BASIN ARE SUFFICIENTLY STRONG TO NECESSITATE A BRISK WIND
ADVISORY FOR THE ICE COVERED LAKE. STRONG WINDS COULD SEPARATE THE
LAKE ICE FROM THE SHORE OR CREATE OPEN LEADS IN THE ICE COVER...
MAKING IT ILL-ADVISED AND POTENTIALLY HAZARDOUS TO VENTURE OUT ON
LAKE ICE DURING THE STRONG WINDS.
HIGH PRESSURE NOSING ACROSS THE REGION WILL BRING A BRIEF DECREASE
IN WINDS TONIGHT BEFORE SOUTHWESTERLIES FRESHEN ONCE AGAIN WEDNESDAY
AS ANOTHER LOW PASSES WELL TO THE NORTH ACROSS NORTHERN
ONTARIO/QUEBEC. THIS WILL BE FOLLOWED BY HIGH PRESSURE THAT SHOULD
BRING ANOTHER PERIOD OF TRANQUIL CONDITIONS WEDNESDAY NIGHT INTO
THURSDAY.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH FROM LATE THURSDAY NIGHT THROUGH LATE FRIDAY NIGHT
FOR NYZ004>008-014.
FLOOD WATCH FROM THURSDAY EVENING THROUGH FRIDAY AFTERNOON FOR
NYZ001>003-010>013-019>021-085.
MARINE...BRISK WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR
LOZ042>044.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...SMITH
SHORT TERM...WOOD
LONG TERM...TMA/WOOD
AVIATION...SMITH
MARINE...SMITH
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
852 AM EST TUE FEB 18 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE AREA THIS MORNING. HIGH
PRESSURE WILL REMAIN SOUTH OF THE AREA TODAY AND TONIGHT. A COLD
FRONT WILL APPROACH THE AREA WEDNESDAY AND MOVE THROUGH WEDNESDAY
NIGHT. ANOTHER FRONT WILL MOVE THROUGH EASTERN NORTH CAROLINA
FRIDAY NIGHT. HIGH PRESSURE WILL BUILD IN SATURDAY AND
SUNDAY...WITH ANOTHER FRONT EXPECTED SUNDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 850 AM TUE...PARTLY TO MOSTLY CLOUDY SKIES ACROSS THE
FORECAST AREA AT PRESENT BUT WILL CLEAR OUT THROUGH THE MORNING.
HOURLY RUC ANALYSIS SHOWS ATMOSPHERE DRYING OUT QUICKLY. WARM
FRONT THAT WAS HUNG UP ALONG THE COAST HAS STARTED MOVING
NORTHWARD ACROSS EASTERN NORTH CAROLINA WITH SOUTHEASTERLY FLOW
BECOMING SOUTHWESTERLY.
UPPER FLOW WILL BECOME QUASI ZONAL THROUGH THE DAY WITH WEAK HIGH
PRESSURE BUILDING IN...TURNING SURFACE FLOW FROM NORTHWESTERLY
BEHIND THE FRONT TO WESTERLY. WESTERLY DOWNSLOPE FLOW WILL HELP
BRING AFTERNOON TEMPERATURES INTO THE 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
AS OS 217 AM TUE...SURFACE HIGH PRESSURE AXIS WILL MOVE OFFSHORE
DURING THE EVENING HOURS...ALLOWING SURFACE FLOW TO BECOME
SOUTHERLY. ANOTHER UPPER LEVEL LOW WILL MOVE THROUGH THE NORTHERN
TIER STATES DURING THE NIGHT...BRINGING WITH IT WEAK UPPER LEVEL
ENERGY AND A HINT OF A WARM FRONT DURING THE EARLY MORNING HOURS
WEDNESDAY...ALLOWING FOR A CHANCE OF SHOWERS AFTER MIDNIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
SCATTERED SHOWERS ASSOCD WITH MID LEVEL TROF WILL CROSS THE FORECAST
AREA WED MORNING THEN MOVE OFF THE COAST DURING MIDDAY TO EARLY
AFTERNOON. DEVELOPING DEEP WEST FLOW AND DECREASING CLOUDS WITH
RISING LOW LEVEL THICKNESSES BOOST TEMPS TO AROUND 70 INLAND WITH
LOW TO MID 60S AT THE BEACHES. A WEAK DRY FRONT DROPS SOUTH ACROSS
THE AREA WED NIGHT THEN LIFTS BACK NORTH ON THU. GIVEN THE LIMITED
FORCING AND LACK OF DEEP MOISTURE WILL KEEP THE DRY FORECAST FOR NOW
ALTHO WUDNT COMPLETELY RULE OUT A SHOWER OR TWO AS THE WARM FRONT
PUSHES NORTH THRU THE AREA THU. A WARM AFTERNOON EXPECTED ON
THU WITH HIGHS REACHING INTO THE LOW 70S INLAND IF ENOUGH SUN CAN
DEVELOP. MILD/WARM TEMPERATURES WILL CONTINUE AHEAD OF A STRONGER
COLD FRONT APPROACHING THE AREA THU NIGHT/FRIDAY. IT STILL APPEARS
THAT MOST PRECIP WILL HOLD OFF UNTIL AFTER SUNRISE FRIDAY BUT A FEW
SHOWERS MAY GRAZE THE SE COAST IN THE MOIST SW FLOW LATE THU NIGHT.
GOOD BAND OF MOISTURE WILL CROSS WITH FRONT FRI AFTN AND KEPT LIKELY
POPS. MDLS SHOWING GOOD SHEAR AND DECENT INSTAB SO THERE MAY BE A
SEVERE THREAT...CONT CHC TSRA WORDING FRI AFTN. WILL BE IN WARM
SECTOR MUCH OF THE DAY WITH HIGHS AGAIN IN THE LOWER 70S INLAND AND
60S CST. THE COLD FRONT PUSHES THRU THE AREA FRIDAY NIGHT BUT MAY
GET HUNG UNDER PARALLEL STEERING FLOW UP JUST OFF THE SE COAST WITH
A LINGERING CHANCE OF SHOWERS THERE THRU SAT MORNING. BROAD TROF
PUSHING THRU THE EASTERN STATES WILL EVENTUALLY SHUNT THE BNDRY
FARTHER OFFSHORE YIELDING GRADUALLY DECREASING CLOUDINESS AND A
RETURN TO MORE SEASONABLE TEMPS THRU THE WEEKEND.
A WEAK COLD FRONT DROPPING THRU THE AREA WILL BRING SOMEWHAT COOLER
TEMPERATURES EARLY NEXT WEEK BUT PRECIP CHANCES WITH THE FRONT
APPEAR TO BE LIMITED GIVEN LACK OF MOISTURE AND WEAK FORCING.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 850 AM TUE...AM EXPECTING CLEAR SKIES BY MIDDAY WITH WESTERLY
DOWNSLOPE FLOW. MODELS DISAGREE ON AMOUNT OF LOW LEVEL MOISTURE
AFTER SUNSET THIS EVENING WITH GFS BRINGING IN LOWER CLOUDS
EARLIER AND NAM REMAINING CLEAR TIL SHORTLY BEFORE SUNRISE WED.
HAVE GONE WITH MVFR AFTER SUNSET IN THE TAFS.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
QUICK MOVING SHORT WAVE WILL SPREAD MOISTURE AND SCATTERED SHRAS
ACROSS THE REGION WED MORN WITH THREAT OF SOME LOWER CIGS/VSBYS.
GENERALLY DRY WED AFTERNOON AND THU WITH MAINLY VFR...CANT RULE
OUT SCT FOG/LOW CLOUDS EARLY THU AS WARM FRONT CROSSES. BETTER CHC
OF REDUCED FLIGHT CATEGORIES LATE THU NIGHT THRU FRI AS COLD FRONT
DROPS INTO THE REGION WITH SCT TO NUMEROUS SHRA/ISOLD TSRA. LOOKS
LIKE DEEPER MOISTURE WILL SLIDE E ON SAT WITH MAINLY VFR EXPECTED.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 850 AM TUE...SEAS IN THE WATERS NORTH OF OREGON INLET ARE
RUNNING 3-5 FEET AND ARE NOT FORECAST TO GO ANY HIGHER SO WILL
DROP THE SMALL CRAFT ADVISORY. SEAS FROM OREGON INLET TO OCRACOKE
ARE AVERAGING 6 FEET SO WILL TRIM BACK THE FORECAST THERE TO 4-6
FEET. WILL BUMP UP WIND SPEEDS IN THAT ZONE AS WELL SINCE DIAMOND
BUOY IS 20-25 KTS WITH HIGHER GUSTS.
PREV DISC...WARM FRONT MOVING NORTH THROUGH THE WATERS. COLD
FRONT EXPECT TO MOVE EAST THROUGH THE WATERS BY MIDDAY. CONDITIONS
TO IMPROVE QUICKLY BEHIND THE FRONT AS GRADIENT RELAXES...DROPPING
WIND AND SEAS BELOW SMALL CRAFT ADVISORY CRITERIA BY MIDDAY. HIGH
RPESSURE WILL BUILD IN DURING THE AFTERNOON. NORTHWESTERLY FLOW
OVER THE WATERS BEHIND THE FRONT WILL BECOME WESTERLY AS THE
SURFACE RIDGE BUILDS IN.
FLOW WILL BECOME SOUTHERLY AGAIN TONIGHT AS THE RIDGE AXIS MOVES
OFFSHORE. ANOTHER UPPER LEVEL SYSTEM WILL MOVE THROUGH THE NORTHERN
TIER STATES...BRINGING WITH IT ANOTHER SYSTEM...WHICH WILL BE
APPROACHING THE AREA TONIGHT. SOUTHERLY FLOW WILL BECOME
SOUTHWESTERLY IN ADVANCE OF THIS FRONT. CONDITIONS EXPECTED TO STAY
BELOW SMALL CRAFT ADVISORY DURING THE NIGHT.
LONG TERM /WEDNESDAY THROUGH SATURDAY/
WSW WINDS INCREASING TO 15 TO 25 KTS WED AND SMALL CRAFT ADVISORIES
WILL LIKELY BE NEEDED. A FRONT DROPS SOUTH THRU THE AREA WED EVENING
WITH WINDS SHIFTING N THEN GRADUALLY DIMINISHING THRU EARLY THU.
WINDS VEER TO SE/S THU/THU NIGHT AS WARM FRONT LIFTS S TO N. SMALL
CRAFT ADVISORIES LIKELY AGAIN AS S/SW WINDS INCREASE TO 20 TO 30 KTS
FRI AHEAD OF THE FRONT WITH SEAS TOPPING OUT AT 6 TO 8 FT OUTER
WATERS. WINDS SHIFT N/NE WINDS AND DIMINISH BEHIND COLD FRONT
PASSAGE LATE FRI NIGHT AND SAT. SEAS GRADUALLY SUBSIDE BLO 6 FT
SATURDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR AMZ152-
154.
&&
$$
SYNOPSIS...HSA
NEAR TERM...HSA/DAG
SHORT TERM...HSA
LONG TERM...RF
AVIATION...HSA/DAG/RF
MARINE...HSA/DAG/RF
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
305 AM EST TUE FEB 18 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE AREA EARLY THIG MORNING. HIGH
PRESSURE WILL REMAIN SOUTH OF THE AREA TODAY AND TONIGHT. A COLD
FRONT WILL APPROACH THE AREA WEDNESDAY AND MOVE THROUGH WEDNESDAY
NIGHT. ANOTHER FRONT WILL MOVE THROUGH EASTERN NORTH CAROLINA FRIDAY
NIGHT. HIGH PRESSURE WILL BUILD IN SATURDAY AND SUNDAY...WITH
ANOTHER FRONT EXPECTED SUNDAY NIGHT.
&&
.NEAR TERM /TODAY/...
AS OF 210 AM TUE...UPPER LOW OVER THE GREAT LAKES AREA WILL BRING A
COLD FRONT THROUGH EASTERN NORTH CAROLINA AROUND SUNRISE THIS
MORNING. MODELS IN GOOD AGREEMENT ON TIMING OF THIS SURFACE
FEATURE...HOWEVER NAM IS FASTER THAN GFS/ECMWF ON SWINGING THE UPPER
LOW THROUGH THE NORTHERN TIER STATES. THIS DOESNT APPEAR TO AFFECT
SENSIBLE WEATHER OVER EASTERN NORTH CAROLINA. ANY SHOWER ACTIVITY
THAT MAY BE LINGERING OVER THE AREA AT THE START OF THE PERIOD WILL
END QUICKLY. UPPER FLOW WILL BECOME QUASI ZONAL THROUGH THE DAY WITH
WEAK HIGH PRESSURE BUILDING IN...TURNING SURFACE FLOW FROM
NORTHWESTERLY BEHIND THE FRONT TO WESTERLY. WESTERLY DOWNSLOPE FLOW
WILL HELP BRING AFTERNOON TEMPERATURES INTO THE 60S.
&&
.SHORT TERM /TONIGHT/...
AS OS 217 AM TUE...SURFACE HIGH PRESSURE AXIS WILL MOVE OFFSHORE
DURING THE EVENING HOURS...ALLOWING SURFACE FLOW TO BECOME
SOUTHERLY. ANOTHER UPPER LEVEL LOW WILL MOVE THROUGH THE NORTHERN
TIER STATES DURING THE NIGHT...BRINGING WITH IT WEAK UPPER LEVEL
ENERGY AND A HINT OF A WARM FRONT DURING THE EARLY MORNING HOURS
WEDNESDAY...ALLOWING FOR A CHANCE OF SHOWERS AFTER MIDNIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
SCATTERED SHOWERS ASSOCD WITH MID LEVEL TROF WILL CROSS THE FORECAST
AREA WED MORNING THEN MOVE OFF THE COAST DURING MIDDAY TO EARLY
AFTERNOON. DEVELOPING DEEP WEST FLOW AND DECREASING CLOUDS WITH
RISING LOW LEVEL THICKNESSES BOOST TEMPS TO AROUND 70 INLAND WITH
LOW TO MID 60S AT THE BEACHES. A WEAK DRY FRONT DROPS SOUTH ACROSS
THE AREA WED NIGHT THEN LIFTS BACK NORTH ON THU. GIVEN THE LIMITED
FORCING AND LACK OF DEEP MOISTURE WILL KEEP THE DRY FORECAST FOR NOW
ALTHO WUDNT COMPLETELY RULE OUT A SHOWER OR TWO AS THE WARM FRONT
PUSHES NORTH THRU THE AREA THU. A WARM AFTERNOON EXPECTED ON
THU WITH HIGHS REACHING INTO THE LOW 70S INLAND IF ENOUGH SUN CAN
DEVELOP. MILD/WARM TEMPERATURES WILL CONTINUE AHEAD OF A STRONGER
COLD FRONT APPROACHING THE AREA THU NIGHT/FRIDAY. IT STILL APPEARS
THAT MOST PRECIP WILL HOLD OFF UNTIL AFTER SUNRISE FRIDAY BUT A FEW
SHOWERS MAY GRAZE THE SE COAST IN THE MOIST SW FLOW LATE THU NIGHT.
GOOD BAND OF MOISTURE WILL CROSS WITH FRONT FRI AFTN AND KEPT LIKELY
POPS. MDLS SHOWING GOOD SHEAR AND DECENT INSTAB SO THERE MAY BE A
SEVERE THREAT...CONT CHC TSRA WORDING FRI AFTN. WILL BE IN WARM
SECTOR MUCH OF THE DAY WITH HIGHS AGAIN IN THE LOWER 70S INLAND AND
60S CST. THE COLD FRONT PUSHES THRU THE AREA FRIDAY NIGHT BUT MAY
GET HUNG UNDER PARALLEL STEERING FLOW UP JUST OFF THE SE COAST WITH
A LINGERING CHANCE OF SHOWERS THERE THRU SAT MORNING. BROAD TROF
PUSHING THRU THE EASTERN STATES WILL EVENTUALLY SHUNT THE BNDRY
FARTHER OFFSHORE YIELDING GRADUALLY DECREASING CLOUDINESS AND A
RETURN TO MORE SEASONABLE TEMPS THRU THE WEEKEND.
A WEAK COLD FRONT DROPPING THRU THE AREA WILL BRING SOMEWHAT COOLER
TEMPERATURES EARLY NEXT WEEK BUT PRECIP CHANCES WITH THE FRONT
APPEAR TO BE LIMITED GIVEN LACK OF MOISTURE AND WEAK FORCING.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 1212 AM TUE...MVFR CONDITIONS PREVELENT ACROSS THE AREA THIS
MORNING WITH WARM FRONT HANGING UP ALONG THE SOUTHERN COASTAL
SECTIONS. FEW SHOWERS OFFSHORE...BUT NOT MOVING TOWARD SHORE AT THIS
TIME. HRRR SEEMS TO HAVE BEST HANDLE ON SITUATION WITH
LOCATION/STRENGTH OF COASTAL TROUGH. HOWEVER IT APPEARS TOO WET.
ISOLATED SHOWERS POSSIBLE AS BOUNDARY WEAKENS AND LIFTS NORTH
THROUGH THE AREA AND COLD FRONT MOVE THROUGH AROUND SUNRISE. HAVE
LEFT THEM OUT OF TAFS AT THIS TIME DUE TO ISOLATED NATURE. SKIES
WILL CLEAR THROUGH THE POST SUNRISE HOURS BEHIND THE COLD FRONT.
MODELS DISAGREE ON AMOUNT OF LOW LEVEL MOISTURE AFTER SUNSET THIS
EVENING WITH GFS BRINGING IN LOWER CLOUDS EARLIER AND NAM REMAINING
CLEAR TIL SHORTLY BEFORE SUNRISE WED. HAVE GONE WITH MVFR AFTER
SUNSET IN THE TAFS.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
QUICK MOVING SHORT WAVE WILL SPREAD MOISTURE AND SCATTERED SHRAS
ACROSS THE REGION WED MORN WITH THREAT OF SOME LOWER CIGS/VSBYS.
GENERALLY DRY WED AFTERNOON AND THU WITH MAINLY VFR...CANT RULE
OUT SCT FOG/LOW CLOUDS EARLY THU AS WARM FRONT CROSSES. BETTER CHC
OF REDUCED FLIGHT CATEGORIES LATE THU NIGHT THRU FRI AS COLD FRONT
DROPS INTO THE REGION WITH SCT TO NUMEROUS SHRA/ISOLD TSRA. LOOKS
LIKE DEEPER MOISTURE WILL SLIDE E ON SAT WITH MAINLY VFR EXPECTED.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 226 AM TUE...WARM FRONT/COASTAL TROUGH HAS STARTED TO MOVE
WEST AT THIS TIME...TURNING FLOW OVER THE WATERS TO SOUTHEASTERLY
RUNNING 10 TO 15 KNOTS WITH SEAS 4 TO 5 FEET. CENTRAL WATERS HAVING
20 KNOT SUSTAINED WITH GUSTS TO 25 AND SEAS TO 6 FEET. CONDITIONS
EXPECTED TO PICK UP IN NORTHERN WATERS BY SUNRISE AS THE FRONT
APPROACHES AND PASSES THROUGH THE COASTAL WATERS. SMALL CRAFT
ADVISORY IN EFFECT FOR THOSE WATERS. CONDITIONS TO IMPROVE QUICKLY
BEHIND THE FRONT AS GRADIENT RELAXES...DROPPING WIND AND SEAS BELOW
SMALL CRAFT ADVISORY CRITERIA BY MIDDAY. HIGH RPESSURE WILL BUILD IN
DURING THE AFTERNOON. NORTHWESTERLY FLOW OVER THE WATERS BEHIND THE
FRONT WILL BECOME WESTERLY AS THE SURFACE RIDGE BUILDS IN.
FLOW WILL BECOME SOUTHERLY AGAIN TONIGHT AS THE RIDGE AXIS MOVES
OFFSHORE. ANOTHER UPPER LEVEL SYSTEM WILL MOVE THROUGH THE NORTHERN
TIER STATES...BRINGING WITH IT ANOTHER SYSTEM...WHICH WILL BE
APPROACHING THE AREA TONIGHT. SOUTHERLY FLOW WILL BECOME
SOUTHWESTERLY IN ADVANCE OF THIS FRONT. CONDITIONS EXPECTED TO STAY
BELOW SMALL CRAFT ADVISORY DURING THE NIGHT.
LONG TERM /WEDNESDAY THROUGH SATURDAY/
WSW WINDS INCREASING TO 15 TO 25 KTS WED AND SMALL CRAFT ADVISORIES
WILL LIKELY BE NEEDED. A FRONT DROPS SOUTH THRU THE AREA WED EVENING
WITH WINDS SHIFTING N THEN GRADUALLY DIMINISHING THRU EARLY THU.
WINDS VEER TO SE/S THU/THU NIGHT AS WARM FRONT LIFTS S TO N. SMALL
CRAFT ADVISORIES LIKELY AGAIN AS S/SW WINDS INCREASE TO 20 TO 30 KTS
FRI AHEAD OF THE FRONT WITH SEAS TOPPING OUT AT 6 TO 8 FT OUTER
WATERS. WINDS SHIFT N/NE WINDS AND DIMINISH BEHIND COLD FRONT
PASSAGE LATE FRI NIGHT AND SAT. SEAS GRADUALLY SUBSIDE BLO 6 FT
SATURDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EST TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY FROM 7 AM TO NOON EST TUESDAY FOR AMZ150.
&&
$$
SYNOPSIS...CGG
NEAR TERM...CGG
SHORT TERM...CGG
LONG TERM...BTC
AVIATION...CGG/BTC
MARINE...CGG/BTC
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
111 AM EST TUE FEB 18 2014
.SYNOPSIS...
A WARM FRONT WILL APPROACH FROM THE SOUTHWEST TONIGHT AND PASS
THROUGH THE AREA TUESDAY MORNING...FOLLOWED SOON AFTER BY A COLD
FRONT FROM THE WEST. ANOTHER FRONT WILL MOVE THROUGH
WEDNESDAY. THE NEXT FRONT COMES THROUGH FRIDAY...BECOMING
STATIONARY OFF THE COAST THIS WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /OVERNIGHT/...
AS OF 107 AM TUE...WARM FRONT HUNG UP ALONG THE COAST THIS
MORNING...HAVING A HARD TIME MAKING ANY PROGRESSION NORTHWARD
INLAND. TEMPERATURES HAVE BOTTOMED OUT AND WILL BE STEADY FOR THE
NEXT COUPLE OF HOURS OR SO...THEN START TO RISE AS THE WARM FRONT
MOVES NORTH. SOME SHOWERS OFFSHORE ALONG THE BOUNDARY...BUT RADAR
LOOPS INDICATE SHOWERS NOT MOVING TOWARD LAND...HOWEVER COULD CLIP
THE OUTER BANKS IN A FEW HOURS. SCATTERED SHOWERS EVIDENT ON RADAR
TO THE WEST WILL BE MOVING OVER EASTERN NORTH CAROLINA WITH BEST
CHANCES IN NORTHERN AREAS. HRRR SEEMS TO HAVE A GOOD HANDLE ON
PLACEMENT OF WARM FRONT AND PRECIPITATION. COLD FRONT EXPECTED TO
MOVE THROUGH AREA AROUND SUNRISE OR A FEW HOURS AFTER SUNRISE.
&&
.SHORT TERM /TUESDAY/...
AS OF 3 PM MON...THE WARM FRONT WILL QUICKLY LIFT THROUGH FROM THE
SOUTH IN THE MORNING...BRINGING AN END TO ANY SHOWER ACTIVITY. THE
ASSOCIATED COLD FRONT WILL PASS THROUGH SOON AFTER THAT AROUND
MIDDAY. ALL THE AVAILABLE MOISTURE FOR SHOWERS WILL BE GONE SO
HAVE NO PRECIP MENTIONED AFTER 15Z. DRY DOWNSLOPING WINDS ACROSS
THE AREA WILL PUSH THE HIGHS INTO THE LOWER/MID 60S ALL AREAS
EXCEPT FOR A FEW DEGREES COOLER ALONG THE OUTER BANKS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
AS OF 3 PM MON...GENERALLY ZONAL FLOW OVER THE REGION EARLY ON
WILL GRADUALLY GIVE WAY TO BROAD RIDGING OVER THE SE STATES LATE
IN THE WEEK WITH MUCH MILDER PERIOD IN STORE. THE MORE AMPLIFIED
FLOW WILL CONTINUE INTO THE WEEKEND WITH BROAD TROF REPLACING THE
RIDGING OVER THE EASTERN STATES.
TEMPERATURES WILL RISE NICELY TUE WITH LOW LEVEL THICKNESS RISES IN
THE DOWNSLOPE FLOW TUE WITH HIGHS REACHING IN THE MID 60S INLAND.
ANOTHER WEAK LOW AMPLITUDE WAVE WILL CROSS THE AREA LATE TUE NIGHT
BRINGING RENEWED PRECIP CHANCES. NAM/GFS/SREF FAIRLY DRY WITH MOST
QPF IMD CST WHILE ECMWF WETTER...HAVE LEANED TWRD DRIER SOLUTION
WITH CHC POPS CST TO SLIGHT CHC INLAND...MAINLY IN THE MORNING.
AFTER PRECIP ENDS EXPECT BREEZY AND WARM CONDITIONS AS GOOD
WESTERLY FLOW DEVELOPS WED AFTERNOON WITH INLAND HIGHS UPR 60S TO
AROUND 70 INLAND.
A WEAK DRY FRONT DROPS SOUTH ACROSS THE AREA WED NIGHT THEN LIFTS
BACK NORTH ON THU. GIVEN THE LIMITED FORCING AND LACK OF DEEP
MOISTURE WILL KEEP THE DRY FORECAST FOR NOW ALTHO WUDNT COMPLETELY
RULE OUT A SHOWER OR TWO AS THE WARM FRONT PUSHES NORTH THRU THE
AREA THU. ANOTHER WARM AFTERNOON EXPECTED ON THU WITH HIGHS
REACHING INTO THE LOW 70S INLAND IF ENOUGH SUN CAN DEVELOP.
MILD/WARM TEMPERATURES WILL CONTINUE AHEAD OF A STRONGER COLD FRONT
APPROACHING THE AREA ON THU NIGHT/FRIDAY. MODELS HAVE BACKED OFF
ON PRECIP CHANCES LATE THU NIGHT INTO EARLY FRI SO HAVE REMOVED
POPS THU NIGHT. GOOD BAND OF MOISTURE WILL CROSS WITH FRONT ESPCLY
FRI AFTN AND RAISED POP TO LIKELY. MDLS SHOWING GOOD SHEAR AND
DECENT INSTAB SO THERE MAY BE A SEVERE THREAT...CONT CHC TSRA
WORDING FRI AFTN. WILL BE IN WARM SECTOR MUCH OF THE DAY WITH
70 TO 75 INLAND AND 60S CST.
GFS/ECMWF COMING INTO BETTER AGREEMENT WITH MORE PROGRESSIVE
FRONTAL PASSAGE. WILL KEEP SMALL CHC POP CST EARLY SAT CST THEN
DRY SAT NIGHT INTO MON AS FRONT MOVES WELL OFFSHORE. TEMPS WILL BE
COOLER BEHIND FRONT WITH HIGHS MAINLY UPR 50S TO LOWER 60S.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TUESDAY/...
AS OF 1212 AM TUE...MVFR CONDITIONS PREVELENT ACROSS THE AREA THIS
MORNING WITH WARM FRONT HANGING UP ALONG THE SOUTHERN COASTAL
SECTIONS. FEW SHOWERS OFFSHORE...BUT NOT MOVING TOWARD SHORE AT THIS
TIME. HRRR SEEMS TO HAVE BEST HANDLE ON SITUATION WITH
LOCATION/STRENGTH OF COASTAL TROUGH. HOWEVER IT APPEARS TOO WET.
ISOLATED SHOWERS POSSIBLE AS BOUNDARY WEAKENS AND LIFTS NORTH
THROUGH THE AREA AND COLD FRONT MOVE THROUGH AROUND SUNRISE. HAVE
LEFT THEM OUT OF TAFS AT THIS TIME DUE TO ISOLATED NATURE. SKIES
WILL CLEAR THROUGH THE POST SUNRISE HOURS BEHIND THE COLD FRONT.
MODELS DISAGREE ON AMOUNT OF LOW LEVEL MOISTURE AFTER SUNSET THIS
EVENING WITH GFS BRINGING IN LOWER CLOUDS EARLIER AND NAM REMAINING
CLEAR TIL SHORTLY BEFORE SUNRISE WED. HAVE GONE WITH MVFR AFTER
SUNSET IN THE TAFS.
LONG TERM /TUESDAY NIGHT THROUGH SAT/...
AS OF 3 PM MON...VFR TUE EVENING WITH MCLR SKIES. QUICK MOVING
SHORT WAVE WILL SPREAD MOISTURE AND POSS SOME SHRA ACROSS REGION LATE
TUE NIGHT AND WED MORN WITH THREAT OF SOME LOWER CIGS/VSBYS.
GENERALLY DRY WED AFTERNOON AND THU WITH MAINLY VFR...CANT RULE
OUT SCT FOG/LOW CLOUDS EARLY THU AS WARM FRONT CROSSES. BETTER CHC
OF REDUCED FLIGHT CATEGORIES FRI AFTN AS COLD FRONT DROPS INTO THE
REGION WITH SCT TO NUMEROUS SHRA/ISOLD TSRA. LOOKS LIKE DEEPER
MOISTURE WILL SLIDE E ON SAT WITH MAINLY VFR EXPECTED.
&&
.MARINE...
SHORT TERM /THROUGH TUE/...
AS OF 110 AM TUE...CONTINUING TO SEE NORTHEASTERLY FLOW OVER THE
WATERS THIS MORNING RUNNING 10 TO 15 KNOTS WITH SEAS 4 TO 6 FEET.
WARM FRONT REMAINS HUNG UP ALONG THE COAST. MODELS INDICATING IT
WILL MOVE THROUGH WATERS OVER THE NEXT COUPLE OF HOURS WITH COLD
FRONT MOVING THROUGH WATERS AFTER SUNRISE...TURNING FLOW TO WESTERLY.
PREV DISC...AS OF 1030 PM MON...LATEST SURFACE AND BUOY DATA
INDICATE NE/E WINDS 10-15 KT WITH GUSTS NEAR 20 KT OFF DIAMOND
SHOALS AND WELL OFF ONSLOW BAY. SEAS CONTINUE 3-5 FT MOST WATERS
THOUGH DIAMOND SHOALS HAS REPORTED 6-7 FT OVER THE PAST 2 HOURS SO
WILL MOVE BACK START OF SCA FOR THE CENTRAL WATERS TO PRESENT TO
ACCOUNT FOR THE LINGERING ELEVATED SEAS. COULD SEE SEAS FALL BELOW 6
FT FOR A FEW HOURS OVERNIGHT BETWEEN THE NE SWELL SUBSIDING AND SW
GRADIENT DEVELOPING. WINDS WILL VEER FROM EAST TO SOUTHEAST
OVERNIGHT AS A WARM FRONT APPROACHES FROM THE SOUTHWEST. THE FRONT
WILL MOVE THROUGH THE MARINE ZONES TUES MORNING WITH WINDS VEERING
FURTHER TO SOUTHWEST...THEN WEST IN THE AFTERNOON. WINDS AND SEAS
WILL INCREASE TO SMALL CRAFT LEVELS FROM DIAMOND SHOALS NORTH FOR
THE FIRST HALF OF THE DAY...ENDING IN THE AFTERNOON AFTER A COLD
FRONT MOVES THROUGH FROM THE WEST AND THE PRESSURE GRADIENT LOOSENS.
LONG TERM /TUESDAY NIGHT THROUGH SAT/
AS OF 3 PM MON...WINDS BECOMING SW AND INCREASING TO 15 TO 20
KTS AGAIN LATER TUE NIGHT AND EARLY WED...POSS 25 KTS OUTER WTRS.
THESE WINDS WILL BUILD SEAS TO 5 TO 7 FT CNTRL AND SRN WTRS. ANOTHER
FRONT DROPS SOUTH THRU THE AREA WED EVENING WITH WINDS SHIFTING N
AND DIMINISHING AGAIN. WINDS GRADUALLY VEER TO S AND SW THU/THU
NIGHT AS WARM FRONT LIFT S TO THE N. THE SW WINDS INCREASE TO 20 TO
30 KTS FRI AHEAD OF THE FRONT WITH SEAS TOPPING OUT AT 6 TO 8 FT
OUTER WATERS. NE WINDS EARLY SAT WILL BECOME LIGHT AND VARIABLE AS
HIGH PRES BUILDS IN WITH SEAS 2 TO 4 FT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EST TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY FROM 7 AM TO NOON EST TUESDAY FOR AMZ150.
&&
$$
SYNOPSIS...HSA
NEAR TERM...CGG
SHORT TERM...HSA
LONG TERM...RF
AVIATION...CGG/RF
MARINE...CGG/DAG/RF
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
512 AM EST TUE FEB 18 2014
.SYNOPSIS...
A WARM FRONT WILL APPROACH FROM THE SOUTHWEST TONIGHT AND PASS
THROUGH THE AREA TUESDAY MORNING...FOLLOWED SOON AFTER BY A COLD
FRONT FROM THE WEST. ANOTHER FRONT WILL MOVE THROUGH
WEDNESDAY. THE NEXT FRONT COMES THROUGH FRIDAY...BECOMING
STATIONARY OFF THE COAST THIS WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /OVERNIGHT/...
AS OF 1040 PM MON...MINOR ADJUSTMENTS TO TEMPS/DEWPOINTS AGAIN AS
THEY HAVE FALLEN QUICKER THAN EXPECTED...ESPECIALLY ALONG HWY 64
WHERE IT APPEARS DECOUPLED WINDS ALLOWED TEMPS TO DROP TO 32-34 F.
DELAYED ONSET OF PRECIP LATER TONIGHT BASED ON LATEST RADAR TRENDS
WHICH INDICATES SOME SCATTERED SHOWERS ABOUT 40-50 NMI OFF THE
CRYSTAL COAST MOVING NORTH...AND BASED ON LATEST RAP/HRRR WHICH
BRINGS PRECIP ALONG THE SOUTHERN COAST AROUND 2-3 AM EST.
FLOW ALOFT REMAINS ZONAL OVERNIGHT. 03Z SURFACE ANALYSES INDICATES
HIGH PRESSURE OFF THE MID-ATLANTIC COAST NOSING SOUTHWEST OVER
EASTERN NC WITH A WEAK INVERTED TROUGH OFFSHORE OF CAPE FEAR. THE
WARM FRONT HAS SHUNTED SOUTH OF ITS LOCATION A FEW HOURS AGO WHICH
WAS ROUGHLY AUGUSTA GA TO NEAR CHARLESTON SC. THE WARM FRONT IS
PROGGED TO APPROACH FROM THE SOUTH LATE TONIGHT. GIVEN T/TD SPREAD
WITH DEWPOINTS IN THE UPPER 20S...REDUCED TEMPS ACROSS THE COASTAL
PLAIN A FEW DEGREES OVERNIGHT WHERE LOWS SHOULD FALL TO 32-34F.
TEMPS MOSTLY UNCHANGED ELSEWHERE WITH UPPER 30S/LOW 40S ALONG THE
COAST. CURRENT SLIGHT CHANCE TO CHANCE POPS ALSO REMAIN UNCHAINED
THOUGH SHOULD BE NOTED THAT LATEST RAP/HRRR/NAM SUGGEST MOST QPF
REMAINS OFF THE COAST WITH A FEW HUNDREDTHS ALONG THE OBX.
&&
.SHORT TERM /TUESDAY/...
AS OF 3 PM MON...THE WARM FRONT WILL QUICKLY LIFT THROUGH FROM THE
SOUTH IN THE MORNING...BRINGING AN END TO ANY SHOWER ACTIVITY. THE
ASSOCIATED COLD FRONT WILL PASS THROUGH SOON AFTER THAT AROUND
MIDDAY. ALL THE AVAILABLE MOISTURE FOR SHOWERS WILL BE GONE SO
HAVE NO PRECIP MENTIONED AFTER 15Z. DRY DOWNSLOPING WINDS ACROSS
THE AREA WILL PUSH THE HIGHS INTO THE LOWER/MID 60S ALL AREAS
EXCEPT FOR A FEW DEGREES COOLER ALONG THE OUTER BANKS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
AS OF 3 PM MON...GENERALLY ZONAL FLOW OVER THE REGION EARLY ON
WILL GRADUALLY GIVE WAY TO BROAD RIDGING OVER THE SE STATES LATE
IN THE WEEK WITH MUCH MILDER PERIOD IN STORE. THE MORE AMPLIFIED
FLOW WILL CONTINUE INTO THE WEEKEND WITH BROAD TROF REPLACING THE
RIDGING OVER THE EASTERN STATES.
TEMPERATURES WILL RISE NICELY TUE WITH LOW LEVEL THICKNESS RISES IN
THE DOWNSLOPE FLOW TUE WITH HIGHS REACHING IN THE MID 60S INLAND.
ANOTHER WEAK LOW AMPLITUDE WAVE WILL CROSS THE AREA LATE TUE NIGHT
BRINGING RENEWED PRECIP CHANCES. NAM/GFS/SREF FAIRLY DRY WITH MOST
QPF IMD CST WHILE ECMWF WETTER...HAVE LEANED TWRD DRIER SOLUTION
WITH CHC POPS CST TO SLIGHT CHC INLAND...MAINLY IN THE MORNING.
AFTER PRECIP ENDS EXPECT BREEZY AND WARM CONDITIONS AS GOOD
WESTERLY FLOW DEVELOPS WED AFTERNOON WITH INLAND HIGHS UPR 60S TO
AROUND 70 INLAND.
A WEAK DRY FRONT DROPS SOUTH ACROSS THE AREA WED NIGHT THEN LIFTS
BACK NORTH ON THU. GIVEN THE LIMITED FORCING AND LACK OF DEEP
MOISTURE WILL KEEP THE DRY FORECAST FOR NOW ALTHO WUDNT COMPLETELY
RULE OUT A SHOWER OR TWO AS THE WARM FRONT PUSHES NORTH THRU THE
AREA THU. ANOTHER WARM AFTERNOON EXPECTED ON THU WITH HIGHS
REACHING INTO THE LOW 70S INLAND IF ENOUGH SUN CAN DEVELOP.
MILD/WARM TEMPERATURES WILL CONTINUE AHEAD OF A STRONGER COLD FRONT
APPROACHING THE AREA ON THU NIGHT/FRIDAY. MODELS HAVE BACKED OFF
ON PRECIP CHANCES LATE THU NIGHT INTO EARLY FRI SO HAVE REMOVED
POPS THU NIGHT. GOOD BAND OF MOISTURE WILL CROSS WITH FRONT ESPCLY
FRI AFTN AND RAISED POP TO LIKELY. MDLS SHOWING GOOD SHEAR AND
DECENT INSTAB SO THERE MAY BE A SEVERE THREAT...CONT CHC TSRA
WORDING FRI AFTN. WILL BE IN WARM SECTOR MUCH OF THE DAY WITH
70 TO 75 INLAND AND 60S CST.
GFS/ECMWF COMING INTO BETTER AGREEMENT WITH MORE PROGRESSIVE
FRONTAL PASSAGE. WILL KEEP SMALL CHC POP CST EARLY SAT CST THEN
DRY SAT NIGHT INTO MON AS FRONT MOVES WELL OFFSHORE. TEMPS WILL BE
COOLER BEHIND FRONT WITH HIGHS MAINLY UPR 50S TO LOWER 60S.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TUESDAY/...
AS OF 1212 AM TUE...MVFR CONDITIONS PREVELENT ACROSS THE AREA THIS
MORNING WITH WARM FRONT HANGING UP ALONG THE SOUTHERN COASTAL
SECTIONS. FEW SHOWERS OFFSHORE...BUT NOT MOVING TOWARD SHORE AT THIS
TIME. HRRR SEEMS TO HAVE BEST HANDLE ON SITUATION WITH
LOCATION/STRENGTH OF COASTAL TROUGH. HOWEVER IT APPEARS TOO WET.
ISOLATED SHOWERS POSSIBLE AS BOUNDARY WEAKENS AND LIFTS NORTH
THROUGH THE AREA AND COLD FRONT MOVE THROUGH AROUND SUNRISE. HAVE
LEFT THEM OUT OF TAFS AT THIS TIME DUE TO ISOLATED NATURE. SKIES
WILL CLEAR THROUGH THE POST SUNRISE HOURS BEHIND THE COLD FRONT.
MODELS DISAGREE ON AMOUNT OF LOW LEVEL MOISTURE AFTER SUNSET THIS
EVENING WITH GFS BRINGING IN LOWER CLOUDS EARLIER AND NAM REMAINING
CLEAR TIL SHORTLY BEFORE SUNRISE WED. HAVE GONE WITH MVFR AFTER
SUNSET IN THE TAFS.
LONG TERM /TUESDAY NIGHT THROUGH SAT/...
AS OF 3 PM MON...VFR TUE EVENING WITH MCLR SKIES. QUICK MOVING
SHORT WAVE WILL SPREAD MOISTURE AND POSS SOME SHRA ACROSS REGION LATE
TUE NIGHT AND WED MORN WITH THREAT OF SOME LOWER CIGS/VSBYS.
GENERALLY DRY WED AFTERNOON AND THU WITH MAINLY VFR...CANT RULE
OUT SCT FOG/LOW CLOUDS EARLY THU AS WARM FRONT CROSSES. BETTER CHC
OF REDUCED FLIGHT CATEGORIES FRI AFTN AS COLD FRONT DROPS INTO THE
REGION WITH SCT TO NUMEROUS SHRA/ISOLD TSRA. LOOKS LIKE DEEPER
MOISTURE WILL SLIDE E ON SAT WITH MAINLY VFR EXPECTED.
&&
.MARINE...
SHORT TERM /THROUGH TUE/...
AS OF 1030 PM MON...LATEST SURFACE AND BUOY DATA INDICATE NE/E
WINDS 10-15 KT WITH GUSTS NEAR 20 KT OFF DIAMOND SHOALS AND WELL
OFF ONSLOW BAY. SEAS CONTINUE 3-5 FT MOST WATERS THOUGH DIAMOND
SHOALS HAS REPORTED 6-7 FT OVER THE PAST 2 HOURS SO WILL MOVE BACK
START OF SCA FOR THE CENTRAL WATERS TO PRESENT TO ACCOUNT FOR THE
LINGERING ELEVATED SEAS. COULD SEE SEAS FALL BELOW 6 FT FOR A FEW
HOURS OVERNIGHT BETWEEN THE NE SWELL SUBSIDING AND SW GRADIENT
DEVELOPING. WINDS WILL VEER FROM EAST TO SOUTHEAST OVERNIGHT AS A
WARM FRONT APPROACHES FROM THE SOUTHWEST. THE FRONT WILL MOVE
THROUGH THE MARINE ZONES TUES MORNING WITH WINDS VEERING FURTHER
TO SOUTHWEST...THEN WEST IN THE AFTERNOON. WINDS AND SEAS WILL
INCREASE TO SMALL CRAFT LEVELS FROM DIAMOND SHOALS NORTH FOR THE
FIRST HALF OF THE DAY...ENDING IN THE AFTERNOON AFTER A COLD FRONT
MOVES THROUGH FROM THE WEST AND THE PRESSURE GRADIENT LOOSENS.
LONG TERM /TUESDAY NIGHT THROUGH SAT/
AS OF 3 PM MON...WINDS BECOMING SW AND INCREASING TO 15 TO 20
KTS AGAIN LATER TUE NIGHT AND EARLY WED...POSS 25 KTS OUTER WTRS.
THESE WINDS WILL BUILD SEAS TO 5 TO 7 FT CNTRL AND SRN WTRS. ANOTHER
FRONT DROPS SOUTH THRU THE AREA WED EVENING WITH WINDS SHIFTING N
AND DIMINISHING AGAIN. WINDS GRADUALLY VEER TO S AND SW THU/THU
NIGHT AS WARM FRONT LIFT S TO THE N. THE SW WINDS INCREASE TO 20 TO
30 KTS FRI AHEAD OF THE FRONT WITH SEAS TOPPING OUT AT 6 TO 8 FT
OUTER WATERS. NE WINDS EARLY SAT WILL BECOME LIGHT AND VARIABLE AS
HIGH PRES BUILDS IN WITH SEAS 2 TO 4 FT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EST TUESDAY FOR AMZ152-154.
SMALL CRAFT ADVISORY FROM 7 AM TO NOON EST TUESDAY FOR AMZ150.
&&
$$
SYNOPSIS...HSA
NEAR TERM...DAG
SHORT TERM...HSA
LONG TERM...RF
AVIATION...CGG/RF
MARINE...RF/HSA/DAG
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
456 PM EST TUE FEB 18 2014
.SYNOPSIS...
A WEAK COLD FRONT PUSHES EAST LATER TONIGHT. A VIGOROUS SYSTEM
PASSES THURSDAY NIGHT...BUT MILD...PACIFIC AIR FOLLOWS IT AS WELL.
A COLD FRONT CROSSES SATURDAY NIGHT,...BEGINNING A TREND TO COLDER.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
THE SYSTEM THAT PRODUCED THE PRECIPITATION LAST NIGHT HAS PUSHED
WELL TO OUR EAST...WITH WEAK HIGH PRESSURE NOW IN CONTROL OF THE
REGION. THE COMBINATION OF ABUNDANT SUNSHINE AND GUSTY SOUTHWESTERLY
WINDS HAVE PUSHED TEMPERATURES INTO THE MID 40S TO MID 50S ACROSS
MUCH OF THE AREA.
THE HIGH WILL PUSH EAST TONIGHT...ALLOWING A COLD FRONT TO
APPROACH FROM THE WEST. EXPECT CLOUDS WILL INCREASE...WITH
PRECIPITATION EXPECTED TO SPREAD NORTHEAST ACROSS THE AREA AFT 06
UTC.
THE COLD FRONT WILL PUSH EAST ON WEDNESDAY...BRINGING THE
PRECIPITATION CHANCES TO AN END.
WITH NAM/GFS AS WELL AS WPC ALL INDICATING MEASURABLE
PRECIPITATION...HAVE BUMPED POPS TO LIKELY...ALONG AND AHEAD OF THE
FRONT. LOOKS LIKE THIS WILL BE A HIGH POP...LOW QPF EVENT.
LATEST TEMP GUIDANCE SUGGESTS LOW TEMP FORECAST FOR TONIGHT AND
HIGHS ON WEDNESDAY ARE IN THE BALLPARK...SO HAVE ONLY MADE SOME
MINOR TWEAKS.
WITH WARMING TEMPS ALOFT AND MOST OF THE REGION SHOULD BE ABOVE
FREEZING AT THE SURFACE...RAIN SHOULD BE THE PREDOMINANT WEATHER
TYPE.
INITIALLY THOUGHT SOME OF THE SHELTERED NORTHERN MOUNTAIN VALLEYS
WILL BE COLD ENOUGH FOR THE PRECIPITATION TO BE IN THE FORM OF
FREEZING RAIN. BUT IT NOW LOOKS LIKE TEMPERATURES WILL FALL
EARLY...AND THEN WARM AS THE CLOUDS AND PRECIPITATION MOVE IN.
MAY BE SOME ISOLATED LOCATIONS THAT COULD SEE FREEZING RAIN...BUT IT
SHOULD NOT LAST LONG...AND BE VERY LIGHT. WITH THIS CHANGE...DO NOT
THINK THERE IS THE NEED FOR ANY FREEZING RAIN ADVISORIES.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
SPRING SPRINGS THIS PERIOD AS STRONG S FLOW AHEAD OF A VIGOROUS S/W
TROUGH / SFC COLD FRONT BRINGS A RATHER MILD THU...FOLLOWED BY THE
THREAT FOR STRONG THUNDERSTORMS THU EVENING.
BUBBLE HIGH EXITS WED EVENING...ALLOWING STRENGTHENING FLOW FROM THE
S AHEAD OF THE NEXT SYSTEM. WARM FRONT ASSOCIATED WITH THIS SYSTEM
MOVES NWD THROUGH THE AREA EARLY THU MORNING THROUGH THE DAY THU.
ELEVATED INSTABILITY IN THE POSITIVE THETA E ADVECTION COULD LEAD TO
THUNDER AHEAD OF AND ALONG THE WARM FRONT AS PW VALUES CLIMB TO
AROUND AN INCH AND SHOWALTERS GO TO ZERO.
WARM SECTOR BECOMES ESTABLISHED BY THU EVENING...BEFORE COLD FRONT
COMES CHARGING THROUGH OVERNIGHT. PW VALUES GET AS HIGH AS ABOUT
1.25 IN AS SFC DEW POINTS APPROACH 50 AND H85 WIND INCREASE TO 70
KTS OR BETTER. INSTABILITY AXIS JUST AHEAD OF THE COLD FRONT WANES
AS IT CROSSES THE AREA THU NT BUT...GIVEN THE STRONG FLOW
ALOFT...ANY CONVECTIVE LINE THAT GETS GOING UPSTREAM CAN MAINTAIN A
DAMAGING WIND THREAT AT LEAST AS FAR E AS THE E EDGE OF THE SLIGHT
RISK AREA...WHICH CUTS N-S THROUGH HTS...WITH STRONG GUSTS POSSIBLE
WELL E OF THERE. THE RUC WIND GUST MOMENTUM ALGORITHM YIELDS GUSTS
TO 40 KTS OVER THE HIGH TERRAIN AND UP TO 30 KTS OVER THE
LOWLANDS...SO IT WILL TAKE HEAVY SHOWERS...OR THUNDERSTORMS...TO
BRING THE GREATER MOMENTUM DOWN. THE HWO ALREADY CARRIES A SEVERE
THREAT IN THE SLIGHT RISK AREA PER PREVIOUS SHIFT.
USED GFS/NAM BLEND FOR QPF WHICH IS UP NEAR AN INCH IN THE
W...DIMINISHING TO AS LITTLE AS A QUARTER OF AN INCH IN THE
MOUNTAINS...WAY TO LITTLE TO RELEASE THE SNOW PACK EVEN WITH STRONG
WINDS AND DEW POINTS ABOVE FREEZING. THE CANADIAN IS AN ODD MODEL
OUT IN NOT PUSHING THE COLD FRONT THROUGH UNTIL FRI MORNING.
IT APPEARS THE COLD ADVECTION BEHIND THIS COLD FRONT WILL BE TOO
WEAK TO COUNTER DIURNAL HEATING FRI...AS TEMPERATURES WILL RECOVER
TO HIGHS ABOVE NORMAL. A BUBBLE HIGH OF PACIFIC ORIGIN PASSES S OF
THE AREA FRI AFTERNOON...AS LOW PRESSURE INTENSIFIES OVER SERN
CANADA. THE GRADIENT BETWEEN THESE TWO FEATURES WILL PRODUCE STRONG
WINDS...ESPECIALLY ACROSS THE N...WHERE THE MOMENTUM ALGORITHM PUMPS
OUT GUSTS AROUND 30 KTS.
BLENDED IN GFS-BASED BIAS CORRECTED MOS FOR HIGHS AND NAM12 AND THE
MET FOR NON-DIURNAL TEMPERATURES BOTH NTS...OVERALL LITTLE CHANGE
FROM PREVIOUS FCST SAVE FOR TIMING OF COLDER AIR THU NT...A LITTLE
LATER.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MODELS SHOWING COLD AIR MOVING BACK INTO THE REGION LATE THIS
WEEKEND. BOTH THE ECMWF AND GFS SHOWING A POTENTIAL ENHANCED CLIPPER
SNOW EARLY NEXT WEEK. HOWEVER...LOTS OF DIFFERENCES IN THE ENSEMBLE
MEMBERS ON THE TIMING OF FEATURES...EVEN THOUGH ENSEMBLES SUPPORT
THE BROADER PATTERN WITH A TROUGH IN THE EAST. THEREFORE...USED THE
ECMWF AND GEFS MEANS...AS CONFIDENCE WITH INDIVIDUAL ENERGY PIECES
IS LOW.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
17Z SATELLITE IMAGERY INDICATES CLEAR SKIES ARE IN PLACE ACROSS
THE ENTIRE AREA. SW TO W WINDS PREVAILED....WITH GUSTS TO 25 KT
COMMON...ESPECIALLY ACROSS THE HIGHER TERRAIN.
EXPECT WINDS WILL DIMINISH THIS EVENING...AND TURN TO THE
SOUTH.
AFTER 6Z...EXPECT PRECIPITATION AND MVFR CONDITIONS...ASSOCIATED
WITH AN APPROACHING COLD FRONT...WILL OVERSPREAD THE AREA. COME OF
THE PRECIPITATION IN THE NORTHERN SHELTERED MOUNTAIN LOCATIONS
COULD FALL AS FREEZING RAIN BETWEEN 09Z AND 15Z.
THE COLD FRONT WILL PUSH THEN EAST BETWEEN 12Z AND 18Z ON
WEDNESDAY. CONDITIONS AT ANY LOCATION SHOULD IMPROVE BEHIND THE
COLD FRONT. IN ADDITION...EXPECT WINDS WILL BECOME GUSTY FROM THE
SW...AND THEN TURN TO THE W BY 18Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF THE ONSET OF PRECIPITATION AND MVFR
PREVALENT CIGS MAY VARY...AND IMPROVEMENT TO VFR TONIGHT/WEDNESDAY
MAY ALSO VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z WEDNESDAY...
IFR POSSIBLE THURSDAY NIGHT IN GUSTY SHOWERS...AND POSSIBLY A STRONG
THUNDERSTORM.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/TRM/RPY
NEAR TERM...ARJ
SHORT TERM...TRM
LONG TERM...RPY
AVIATION...JSH
AREA FORECAST DISCUSSION
NWS TULSA OK
1131 AM CST TUE FEB 18 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
GUSTY SOUTHERLY WINDS WILL CONTINUE THROUGH THE DAY...WITH A WIND
SHIFT OCCURRING OVERNIGHT AS A FRONT MOVES THROUGH THE REGION. LOW
CLOUDS WILL SPREAD INTO SE OK TOMORROW AND MAY IMPACT KMLC BY LATE
MORNING.
&&
.PREV DISCUSSION... /ISSUED 1046 AM CST TUE FEB 18 2014/
..UPDATE...
DISCUSSION...
12Z REGIONAL SOUNDINGS SHOWED POTENTIAL FOR STRONG WARMING TODAY
ALONG WITH VERY DRY PROFILES. CIRRUS OVERSPREADING THE REGION WILL
NOT IMPACT TEMPS TOO MUCH...AND GUSTY SOUTHERLY WINDS WILL BE
MAINTAINED ESPECIALLY AS MIXING DEPTH INCREASES. THE LARGEST
UNCERTAINTY IS DEWPOINT TRENDS THROUGH THE AFTERNOON...WITH LARGE
SPREAD AMONGST SHORT TERM DATA. THE MIXING INTO THE DEEP DRY AIR
WILL ATTEMPT TO BE OFFSET BY LOW LEVEL MOISTURE ADVECTION FROM
EAST TX. NAM DATA SEEMS TO BE MUCH TO AGGRESSIVE WITH THIS
TREND...WHILE THE RAP DATA TOO PESSIMISTIC GIVEN RECENT TRENDS.
UPDATED FORECAST LOWERED AFTERNOON DEWPOINTS BUT STILL MAINTAINED
A STEADY RISE. THE RESULTANT FIRE WEATHER PARAMETERS WERE PUSHED
INTO RED FLAG CRITERIA WITH THIS ADJUSTMENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 74 38 68 56 / 0 0 10 20
FSM 75 42 69 57 / 0 0 10 10
MLC 73 44 70 58 / 0 0 10 10
BVO 74 32 66 52 / 0 0 10 40
FYV 70 37 65 54 / 0 0 10 20
BYV 70 38 63 51 / 0 0 10 20
MKO 74 41 68 56 / 0 0 10 20
MIO 71 35 65 54 / 0 0 10 30
F10 74 42 69 56 / 0 0 10 20
HHW 75 49 71 59 / 0 10 10 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 6 PM TUESDAY FOR OKZ054-OKZ055-OKZ056-
OKZ057-OKZ058-OKZ059-OKZ060-OKZ061-OKZ062-OKZ063-OKZ064-
OKZ065-OKZ066-OKZ067-OKZ068-OKZ069-OKZ070.
AR...RED FLAG WARNING UNTIL 6 PM TUESDAY FOR ARZ001-ARZ002-ARZ010-
ARZ011.
&&
$$
AVIATION...07
AREA FORECAST DISCUSSION
NWS TULSA OK
1046 AM CST TUE FEB 18 2014
...UPDATE...
.DISCUSSION...
12Z REGIONAL SOUNDINGS SHOWED POTENTIAL FOR STRONG WARMING TODAY
ALONG WITH VERY DRY PROFILES. CIRRUS OVERSPREADING THE REGION WILL
NOT IMPACT TEMPS TOO MUCH...AND GUSTY SOUTHERLY WINDS WILL BE
MAINTAINED ESPECIALLY AS MIXING DEPTH INCREASES. THE LARGEST
UNCERTAINTY IS DEWPOINT TRENDS THROUGH THE AFTERNOON...WITH LARGE
SPREAD AMONGST SHORT TERM DATA. THE MIXING INTO THE DEEP DRY AIR
WILL ATTEMPT TO BE OFFSET BY LOW LEVEL MOISTURE ADVECTION FROM
EAST TX. NAM DATA SEEMS TO BE MUCH TO AGGRESSIVE WITH THIS
TREND...WHILE THE RAP DATA TOO PESSIMISTIC GIVEN RECENT TRENDS.
UPDATED FORECAST LOWERED AFTERNOON DEWPOINTS BUT STILL MAINTAINED
A STEADY RISE. THE RESULTANT FIRE WEATHER PARAMETERS WERE PUSHED
INTO RED FLAG CRITERIA WITH THIS ADJUSTMENT.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 74 38 68 56 / 0 0 10 20
FSM 75 42 69 57 / 0 0 10 10
MLC 73 44 70 58 / 0 0 10 10
BVO 74 32 66 52 / 0 0 10 40
FYV 70 37 65 54 / 0 0 10 20
BYV 70 38 63 51 / 0 0 10 20
MKO 74 41 68 56 / 0 0 10 20
MIO 71 35 65 54 / 0 0 10 30
F10 74 42 69 56 / 0 0 10 20
HHW 75 49 71 59 / 0 10 10 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...RED FLAG WARNING UNTIL 6 PM TUESDAY FOR OKZ054-OKZ055-OKZ056-
OKZ057-OKZ058-OKZ059-OKZ060-OKZ061-OKZ062-OKZ063-OKZ064-
OKZ065-OKZ066-OKZ067-OKZ068-OKZ069-OKZ070.
AR...RED FLAG WARNING UNTIL 6 PM TUESDAY FOR ARZ001-ARZ002-ARZ010-
ARZ011.
&&
$$
SHORT TERM...07
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
321 PM CST TUE FEB 18 2014
...MAJOR WINTER STORM TO POSSIBLY IMPACT THE FORECAST AREA THURSDAY
INTO THURSDAY NIGHT...
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 321 PM CST TUE FEB 18 2014
CURRENTLY AS OF 21Z...WATER VAPOP LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED SHORTWAVE TROUGHS OVER MANITOBA AND OVER EASTERN SOUTH DAKOTA
INTO NEBRASKA...RIDGING OVER THE NORTHERN ROCKIES...AND A POTENT
UPPER TROUGH JUST OFF THE BRITISH COLUMBIA AND PACIFIC NORTHWEST
COASTS. THIS POTENT UPPER TROUGH IS THE CULPRIT FOR OUR THURSDAY
STORM. DPVA AND PACIFIC MOISTURE AHEAD OF THE TWO SHORTWAVE TROUGHS
HAVE BEEN SPREADING MID AND HIGH CLOUDS ACROSS THE FORECAST AREA
TODAY. THESE CLOUDS HAVE LIMITED SOME INSOLATION...BUT SOUTHWESTERLY
925-850MB FLOW AHEAD OF A COLD FRONT MOVING INTO THE FORECAST AREA
HELPED BOOST TEMPERATURES INTO THE 30S TO MID 40S THIS AFTERNOON.
OVER WESTERN IOWA WHERE NO SNOW EXISTS...READINGS ARE IN THE 50S TO
LOW 60S. IN THE WAKE OF THE COLD FRONT...READINGS ARE STILL IN THE
30S AND 40S...PARTIALLY DUE TO A BIT MORE SUN AND DOWNSLOPING FLOW
OFF THE NORTHERN ROCKIES.
THE QUIET BEFORE THE STORM PHRASE WORKS PERFECTLY FOR THE SHORT
TERM. 18.12Z MODEL GUIDANCE DEPICT THE RIDGING OVER THE NORTHERN
ROCKIES MARCHING EASTWARD TO ABOUT OVER THE FORECAST AREA BY 00Z
THU...PUSHED BY THE POTENT NORTHEAST PACIFIC NORTHWEST TROUGH
PLOWING INTO THE ROCKIES. ON THE EAST SIDE OF THE UPPER RIDGE AXIS
THERE IS A WEAK SHORTWAVE AT 500MB SUGGESTED TO DROP SOUTHEAST
THROUGH THE FORECAST AREA LATE TONIGHT...BUT THIS FEATURE WILL COME
THROUGH DRY WITH BASICALLY NO CLOUD.
ONLY REAL ISSUE TO CONTEND WITH TONIGHT IS IF ANY FOG CAN FORM
RESULTING FROM MELTING SNOW. ALL MODELS KEEP A DECENT PRESSURE
GRADIENT IN PLACE TONIGHT WITH A SURFACE RIDGE AXIS ONLY REACHING
WESTERN MN BY 12Z WED. 925MB WINDS STAY UP 20-30 KT FOR MUCH OF THE
NIGHT IN THE WAKE OF THE COLD FRONTAL PASSAGE THIS EVENING.
THUS...THINK ANY FOG WOULD BE LIMITED TO PERHAPS THE TYPICAL COLD
SPOTS AND SOME SMALL VALLEYS.
PLENTY OF SUN LOOKS ON TAP FOR WEDNESDAY...OUTSIDE OF SOME CLOUDS
INCREASING LATE AS THE RIDGE AXIS APPROACHES. 925MB TEMPS IN THE 0-
2C RANGE AT 18Z WED SUPPORTS HIGHS IN THE 30S TO A COUPLE
40S...WARMEST IN SOUTHWEST WI.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 321 PM CST TUE FEB 18 2014
...WINTER STORM FOR WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...
MANY FACETS OF THE STORM TO TALK ABOUT...
MODEL ANALYSIS...18.12Z GUIDANCE CONTINUES TO FOLLOW THE PAST COUPLE
OF CYCLES...PHASING TROUGHING OVER THE ROCKIES ON TOP OF THE
FORECAST AREA THURSDAY. THE PHASED UPPER TROUGH ALSO BECOMES
NEGATIVELY TITLED AS IT LIFTS THROUGH THE FORECAST AREA THURSDAY
EVENING. OVERALL...THE SPREAD IN GUIDANCE FROM 500MB TO THE SURFACE
IS FAIRLY LOW CONSIDERING THIS IS A PHASING TROUGH AND STILL ISNT
ONSHORE YET. THEREFORE...CONFIDENCE IS INCREASING THAT A HIGH IMPACT
WINTER STORM WILL AFFECT THE FORECAST AREA.
WINDS...MOST OF THE GUIDANCE IS IN AGREEMENT THAT AS THE PHASING
TAKES PLACE OF THE UPPER TROUGH...THE SURFACE LOW IS GOING TO
UNDERGO BOMBOGENESIS...DROPPING FROM A PRESSURE OF 995MB IN EASTERN
KS AT 12Z THU TO AROUND 970MB OVER LAKE SUPERIOR AT 12Z FRI. TO
HANDLE THIS PRESSURE DROP AND THE COLD AIR THAT GETS PULLED
IN...925MB WINDS INCREASE OUT OF THE WEST-NORTHWEST AT 30-50 KT ON
THE BACK SIDE OF THE STORM FOR THURSDAY EVENING. THE STRONGEST CORE
TRACKS ACROSS SOUTHEAST MN AND NORTHEAST IOWA...THE FAVORABLE
BLIZZARD AREA.
PRECIPITATION...THERE IS SOME UNCERTAINTY ON HOW QUICK PRECIPITATION
DEVELOPS. GFS/NAM/ECMWF SOUNDINGS DEPICT A DECENT DRY LAYER BETWEEN
900-700MB WEDNESDAY NIGHT...WITH MUCH OF THE LIFT FROM WARM
ADVECTION IN THAT LAYER VERSUS IN THE MID/HIGH CLOUDS ABOVE IT.
PRECIPITATION SHOULD STAND A MUCH BETTER CHANCE MOVING IN
THURSDAY...LIKELY SOUTH TO NORTH...AS THE STORM SYSTEM MOVES INTO
SOUTHERN WI. DURING THE AFTERNOON...FRONTOGENESIS IN THE MID/UPPER
LEVELS REALLY INTENSIFIES WITH THE APPROACH OF THE UPPER TROUGH...
WHICH SHOULD DEVELOP A STRONG AND HEAVY PRECIPITATING COLD CONVEYOR
BELT. PRECIPITABLE WATER PROGGED BETWEEN 0.5-0.75 INCHES OR 200-250
PERCENT OF NORMAL SUGGESTS PLENTY OF MOISTURE AVAILABLE FOR THE
FORCING TO PRODUCE FAIRLY HEAVY QPF. CROSS-SECTIONS EVEN SHOW A
LARGE AREA OF NEGATIVE EPV AND SOME WEAK CAPE IN THE AFTERNOON...
SUGGESTING THUNDER COULD OCCUR. WILL SEE IF THIS TRENDS HOLDS WITH
LATER MODELS. COLD CONVEYOR BELT WILL GRADUALLY LIFT INTO THE U.P.
OF MI THU NIGHT...GRADUALLY ENDING PRECIPITATION SOUTHWEST TO
NORTHEAST.
PRECIPITATION TYPE...A DRY WARM LAYER ALOFT SHOULD RESIDE OVER THE
FORECAST AREA WEDNESDAY NIGHT. AS THE PRECIPITATION SPREADS IN LATE
WEDNESDAY NIGHT/THURSDAY MORNING...THAT COULD FALL AS EITHER
SLEET...FREEZING RAIN OR RAIN UNTIL EVAPORATIVE COOLING SWITCHES IT
OVER TO SNOW. THE AFTERNOON IS TRICKY AND COMPLETELY DEPENDS ON THE
850MB LOW TRACK. AHEAD OF THE 850MB LOW...A WARM LAYER ALOFT AND AT
THE SURFACE WILL ADVECT NORTH...RESULTING IN A MIX OR COMPLETELY
SWITCHOVER TO RAIN. RIGHT NOW THIS SEEMS MOST PROBABLE TO OCCUR IN
FAR SOUTHEAST SECTIONS OF THE FORECAST AREA FROM 15-21Z THU. IF THE
LOW TRACKS FARTHER NORTHWEST LIKE THE 18.12Z UKMET...THEN RAIN COULD
FALL EVEN AT LA CROSSE. HOWEVER...THE UKMET IS A NORTHWEST OUTLIER.
SNOW AMOUNTS/ICE ACCUMULATION...ANY ICE ACCUMULATION LOOKS TO BE
LATE WEDNESDAY NIGHT FROM THE INITIAL WARM LAYER. EVEN SNOW AMOUNTS
REALLY DO NOT START TO PICK UP UNTIL LATE THURSDAY MORNING WHEN
HEAVIER PRECIPITATION BEGINS TO DEVELOP. DURING THURSDAY AFTERNOON
AND EVENING...1 TO 2 INCH PER HOUR RATES ARE POSSIBLE...ESPECIALLY
IF CONVECTION FORMS. PRESENTLY DEPICT 2 TO 10 INCHES FOR
TOTALS...HIGHEST IN NORTH CENTRAL WI WHERE THE LONGEST DURATION OF
SNOW IS EXPECTED. IMPORTANT...THESE AMOUNTS ARE SUBJECT TO
CHANGE...AS EVEN THE NEW 18.18Z NAM SUGGESTS OF A FOOT IN SOUTHEAST
MN.
...REST OF THE LONG TERM PERIOD...
AFTER THE WINTER STORM...THE WEATHER GETS QUIET. 18.12Z
ECMWF/CANADIAN/GFS AND ENSEMBLE DATA REMAIN CONSISTENT IN FORMING AN
OMEGA BLOCK FROM THE U.S. WEST COAST INTO ALASKA...RESULTING IN DEEP
TROUGHING OVER MUCH OF CANADA AND INTO THE UPPER MIDWEST. THIS
ALLOWS FOR A GRADUAL COOLING TREND FROM FRIDAY THROUGH NEXT
TUESDAY...AND ACCORDING TO THE CFS WOULD CONTINUE THROUGH THE REST
OF THE MONTH. WIND CHILLS THROUGH TUESDAY LOOK TO STAY JUST ABOVE
WIND CHILL ADVISORY CRITERIA...I.E. -20 F. DESPITE THE COOLING
TREND...THERE ARE NOT THAT MANY PRECIPITATING SYSTEMS TO DEAL WITH.
THERE ARE SOME HINTS OF A WEAK SHORTWAVE CROSSING THE SOUTHERN
PORTION OF THE FORECAST AREA FRIDAY NIGHT WITH SOME LIGHT SNOW.
LOOKING OUT TO MONDAY AND MONDAY NIGHT OUR SOUTHERN FORECAST AREA
COULD ALSO GET CLIPPED BY A MID LEVEL FRONTOGENESIS BAND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY NOON)
ISSUED AT 1133 AM CST TUE FEB 18 2014
GOOD VFR CONDITIONS EXPECTED THIS AFTERNOON THRU AT LEAST WED
MORNING. VALLEY INVERSIONS HAVE LIFTED/BROKEN WITH TEMPERATURES
ACROSS THE AREA MOSTLY IN THE LOW-MID 30S AS OF 17Z. WITH DEEPER
MIXING...VSBYS ACROSS THE AREA ARE 10SM...AND LOOK TO REMAIN SO THRU
TONIGHT/WED MORNING. A COLD FRONT WILL MOVE EAST ACROSS THE AREA
LATER THIS AFTERNOON/EARLY THIS EVENING...AROUND 21Z AT KRST AND 00Z
AT KLSE. SOUTH AND SOUTHWEST WINDS EARLY THIS AFTERNOON WILL BECOME
NORTHWEST LATER THIS AFTERNOON AND TONIGHT. DRY LOWER LEVEL AIR
BEHIND THIS BOUNDARY...SO CLOUDS THRU TONIGHT/WED EXPECTED TO REMAIN
AT OR ABOVE 15K FT. ENOUGH OF A PRESSURE GRADIENT BEHIND THIS FRONT
AND ACROSS MN/IA/WI TONIGHT FOR NORTHWEST WINDS IN THE 8-12KT
RANGE...ENOUGH TO KEEP ANY LATE NIGHT/EARLY MORNING HZ/BR TO A
MINIMUM AT BOTH VALLEY AND HIGHER ELEVATION SITES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY
NIGHT FOR WIZ017-029-032>034-041>044-053>055-061.
MN...BLIZZARD WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY NIGHT
FOR MNZ086-087-094-095.
WINTER STORM WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY
NIGHT FOR MNZ079-088-096.
IA...BLIZZARD WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY NIGHT
FOR IAZ008>010-018-019-029.
WINTER STORM WATCH FROM THURSDAY MORNING THROUGH LATE THURSDAY
NIGHT FOR IAZ011-030.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 PM CST MON FEB 17 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 310 PM CST MON FEB 17 2014
CURRENTLY AS OF 21Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED NEARLY ZONAL FLOW ACROSS MUCH OF THE NORTHERN
U.S....WITH THE BIG EXCEPTION FOR A NARROW BUT POTENT/DEEP
SHORTWAVE TROUGH EXTENDING FROM MINNESOTA INTO EASTERN MISSOURI.
STRONG LIFT AHEAD OF THE TROUGH COMBINED WITH A SURGE OF
PRECIPITABLE WATER AROUND A 0.5 INCH PER 12Z MPX SOUNDING BROUGHT
SNOW TO MUCH OF THE FORECAST AREA. THIS SNOW WAS VERY EFFICIENT IN
REDUCING VISIBILITIES...WITH MANY LOCATIONS SEEING 3-4 HOURS OF
1/2 MILE OR LESS...AIDED TOO BY WINDS THAT GUSTED 20 TO 30 MPH.
ROADS QUICKLY DETERIORATED TOO. SNOWFALL ACCUMULATIONS...ON THE
OTHER HAND...WERE LESS THAN EXPECTED DESPITE THE STRONG FORCING.
BELIEVE SOME LEFT-OVER DRY AIR SEEN ON THE 12Z DVN SOUNDING
ABSORBED SOME OF THE SNOW...AND KEPT THE SNOW FROM ORGANIZING INTO
ONE SOLID AREA. IT ALSO APPEARS THAT THE STRONGEST LIFT ENDED UP
SHIFTING SOUTH...INITIALLY PROGGED OVER NORTHERN WISCONSIN ON
FRIDAY TO OVER THE FORECAST AREA YESTERDAY AND IN REALITY ENDED UP
OVER ILLINOIS. STRONG SUBSIDENCE IN THE WAKE OF THE SHORTWAVE
TROUGH HAS LED TO CLEARING SKIES IN MN AND IA. WARMER AIR IS ALSO
ACCOMPANYING THE CLEARING...WITH READINGS IN THE 30S ALONG AND
WEST OF I-35.
ANY LINGERING SNOW ALONG/EAST OF THE MISSISSIPPI RIVER WILL PUSH
OFF TO THE EAST EARLY THIS EVENING. CLEARING SHOULD THEN WORK ITS
WAY ACROSS THE FORECAST AREA TONIGHT AS 500MB HEIGHTS RISE IN THE
WAKE OF THE SHORTWAVE TROUGH. ATTENTION THEN TURNS TO A STRING OF
SHORTWAVES STRETCHING FROM WASHINGTON STATE INTO SOUTHERN
SASKATCHEWAN. THESE SHORTWAVES ARE PROGGED BY ALL MODELS TO DIG
INTO THE REGION TUESDAY AFTERNOON. AHEAD OF THESE SHORTWAVES...A
PLUME OF WARMER 925-850MB AIR IS FORECAST...WITH 925MB TEMPS
CLIMBING TO 2-6C BY 12Z TUESDAY. THESE TEMPS GRADUALLY COOL
THROUGH THE DAY AS THE SHORTWAVES APPROACH...BUT THE COMBINATION
OF FILTERED SUNSHINE AND THESE WARMER TEMPS SHOULD ALLOW HIGHS TO
CLIMB INTO THE MID 30S TO LOW 40S. BOTH THE 17.12Z GFS AND ECMWF
HINT AT SOME LIGHT QPF PRODUCED FROM THESE SHORTWAVES AS WELL IN
THE AFTERNOON. SOUNDINGS DEPICT A DRY LAYER BETWEEN 700-900MB TO
OVERCOME...SO FOR NOW HAVE KEPT ANY PRECIPITATION OUT OF THE
FORECAST. WOULD NOT BE SURPRISED IF SOME SPRINKLES OCCUR...THOUGH.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 310 PM CST MON FEB 17 2014
THERE ARE TWO ITEMS OF CONCERN IN THE LONG TERM...A POSSIBLE HIGH
IMPACT WINTER STORM FOR THURSDAY...AND THEN MORE BELOW NORMAL
TEMPERATURES FOR FRIDAY AND BEYOND.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...MENTIONED IN YESTERDAYS
DISCUSSION MODELS HAD TRENDED AWAY FROM HAVING A CENTRAL PLAINS
STORM AFFECTING THE AREA. THAT HAS COMPLETELY CHANGED WITH THE
17.12Z MODELS. THE EVOLUTION OF THIS STORM IS A RESULT OF PHASING OF
TWO SHORTWAVE TROUGHS...AT 12Z THURSDAY PROGGED OVER KANSAS AND THE
DAKOTAS. THE PHASING LOOKS TO BEGIN OVER THE FORECAST AREA THURSDAY
AFTERNOON...RESULTING IN A RAPIDLY DEEPENING SURFACE LOW BEING
PULLED NORTH FROM EASTERN KANSAS INTO UPPER MI. PLENTIFUL MOISTURE
FROM THE GULF OF MEXICO SHOULD ADVECT NORTH INTO THE FORECAST AREA
AHEAD OF THE STORM...WITH PRECIPITABLE WATER VALUES PROGGED TO REACH
0.5-0.75 INCHES. WITH 17.12Z MODEL CONSENSUS ALL HEADING TOWARD THE
PHASED IDEA...INCREASING PRECIPITATION CHANCES...ESPECIALLY FOR
THURSDAY. BEING PHASED...THERE ARE GOING TO BE ISSUES...
1. PRECIPITATION TYPE. THERE IS SOME WARM AIR AROUND WEDNESDAY
NIGHT...WITH WARM LAYER ALOFT TEMPS AROUND 3C...WHICH WHEN THE
INITIAL PRECIPITATION STARTS TO FALL COULD END UP BEING AS
RAIN...FREEZING RAIN OR SLEET. EVAPORATIVE COOLING SHOULD THEN ALLOW
THE TYPE TO GO OVER TO SNOW. THIS IS TEMPORARY FOR THE SOUTHEAST
HALF OF THE FORECAST AREA...BECAUSE AS WE HEAD INTO THE DAY
THURSDAY...WARM AIR COMES BACK IN FROM THE SOUTH. AT THE SAME TIME
DAYTIME HEATING IS HELPING TO BRING TEMPERATURES UP INTO THE MID 30S
ALONG THE MS RIVER AND EAST. SO A MIX WITH RAIN IS POSSIBLE. THESE
PRECIPITATION TYPE ISSUES ARE GOING TO CREATE HAVOC WITH FORECASTING
SNOWFALL AMOUNTS.
2. SNOWFALL AMOUNTS. THE NORTHWEST / DEFORMATION SIDE OF THIS STORM
COULD EASILY PUT DOWN SOME HEAVY SNOW IF THE PHASING OCCURS AS
PLANNED. THE NEW 17.18Z NAM REALLY HITS AN AREA FROM NORTH CENTRAL
IOWA INTO CENTRAL WISCONSIN HARD WITH UPWARDS OF 1-1.5 INCHES OF
QPF. THIS IS ON THE HIGH SIDE OF ALL AVAILABLE GUIDANCE...INCLUDING
THE 15.09Z/15.15Z SREF...BUT REFLECTS THAT WE NEED TO WATCH THE
STORM. WHERE THE DEFORMATION TRACKS TOO DEPENDS ON THE STORM TRACK.
3. WINDS ON THE BACK SIDE FOR THURSDAY AFTERNOON/NIGHT. 925MB WINDS
FROM THE 17.12Z GFS AND ECMWF ARE SUGGESTED TO INCREASE TO 30-40 KT
IN A STRONG COLD ADVECTION REGIME THURSDAY EVENING. THESE WINDS
COULD RESULT IN EXTENSIVE BLOWING OF THE SNOW. INCREASED WINDS AND
MENTIONED BLOWING SNOW...BUT MAY NEED TO RAISE WINDS MORE.
WITH THE CURRENT STORM SYSTEM STILL LINGERING AROUND...AND THAT THE
MODELS HAVE JUST TRENDED BACK TO A PHASED SYSTEM...HAVE DECIDED NOT
TO ISSUE A WINTER STORM WATCH AT THIS POINT. HOWEVER...SHOULD MODELS
SHOW THE SAME THING AGAIN TONIGHT...WATCHES MAY BE NEEDED...
ESPECIALLY OVER THE NORTHWEST HALF OF THE FORECAST AREA.
FRIDAY INTO EARLY NEXT WEEK...17.12Z GFS/ECMWF/CANADIAN REMAIN IN
GOOD AGREEMENT ON A COOL DOWN EACH DAY. THIS COOL DOWN IS A RESULT
OF AN OMEGA BLOCK THAT DEVELOPS FROM ALASKA DOWN THE WEST COAST OF
THE U.S...CAUSING DEEP TROUGHING OVER MUCH OF CANADA INTO THE UPPER
MIDWEST. FOLLOWING A MODEL CONSENSUS FORECAST...WE COULD BE
APPROACHING WIND CHILL ADVISORY CONCERNS AGAIN AS EARLY AS MONDAY.
EVEN COLDER AIR APPEARS TO BE LURKING BEYOND MONDAY...ESPECIALLY IN
THE ECMWF AND CFS. THIS DEEP UPPER TROUGHING FORMING PUSHES MOST
PRECIPITATING SYSTEMS SOUTH OF THE FORECAST AREA...BUT DO HAVE SOME
LOW CHANCES OF SNOW HERE AND THERE FOR SHORTWAVES TRAVERSING THE
BOTTOM OF THE TROUGH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1100 PM CST MON FEB 17 2014
LOW MVFR CIGS BEEN STUBBORN TO CLEAR KLSE...BUT ON THE DOORSTEP PER
LATEST FOG/STRATUS SATELLITE IMAGERY. RAP13 RH FIELDS DO PRESS IT
EAST...AND EXPECT SKC BY 06Z.
WINDS WILL BECOME MORE SOUTHERLY ON TUE...AHEAD OF ANOTHER SFC
BOUNDARY. NOT EXPECTING ANY PCPN WITH THIS FRONT...MOSTLY MID/HIGH
LEVEL CLOUDS. COULD GET SOME LOW SCT...POTENTIALLY A FEW HOURS
BKN025. GOING TO KEEP CONDITIONS VFR FOR NOW. WITH ANOTHER WEAK
RIDGE FOR WED...VFR CONDITIONS SHOULD BE THE RULE FOR A COUPLE DAYS.
THU COULD SEE ANOTHER SIGNIFICANT WINTER STORM BLAST ACROSS THE
AREA. SIGNIFICANT SNOWFALL WITH PROLONGED LIFR/IFR CONDITIONS COULD
RESULT. WINDS PICK UP BY LATE AFTERNOON - WHICH WOULD RESULT IN LOW
VSBYS FROM BLSN AT KRST THROUGH THE NIGHT. TOO EARLY TO SAY AS STORM
TRACK IS NOT CERTAIN...BUT SOMETHING TO WATCH.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM....AJ
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1152 PM MST WED FEB 19 2014
.UPDATE...
ISSUED AT 1151 PM MST WED FEB 19 2014
LOADED LATEST OBSERVATIONS AND BLENDED TO REST OF FORECAST.
ALSO...ADJUSTED PRECIP COVERAGE TO REFLECT CURRENT RADAR.
NO OTHER UPDATES AT THIS TIME. LW
UPDATE ISSUED AT 850 PM MST WED FEB 19 2014
ADDING SNOW/BLOWING SNOW ADVISORY TO TELLER/NORTHERN EL PASO COUNTIES
FOR THE REST OF TONIGHT...BASED ON RADAR/SATELLITE TRENDS AND HI RES
MODEL FORECASTS FOR THE REMAINDER OF THE NIGHT. HRRR DEVELOPS GOOD
PERIOD OF SNOW/BLOWING SNOW ACROSS TELLER/MAINLY NORTHERN EL PASO
COUNTIES SHORTLY AND THEN CONTINUING FOR SEVERAL HOURS BEFORE
ENDING. ADVISORY AND UPDATED PRODUCTS WILL BE OUT SHORTLY. LW
UPDATE ISSUED AT 701 PM MST WED FEB 19 2014
LOADED LATEST OBSERVATIONS AND BLENDED INTO FORECAST. ADJUSTED
SKY COVER AND PRECIP GRIDS TO REFLECT LATEST RADAR AND SATELLITE
TRENDS...AS WELL AS SHORT TERM HI RES MODEL FORECASTS. LW
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 333 PM MST WED FEB 19 2014
STRONG UPPER TROUGH MOVING QUICKLY EASTWARD THROUGH THE GREAT BASIN
INTO WESTERN COLORADO THIS AFTERNOON...WITH SNOW DEVELOPING AND EVEN
A COUPLE LIGHTNING STRIKES WEST OF THE CONTINENTAL DIVIDE THIS
AFTERNOON. EXPECT SNOW TO BEGIN BY SUNSET OVER THE CENTRAL AND
SOUTHWEST MOUNTAINS...WITH A PERIOD OF HEAVY SNOW AND BLOWING SNOW
OVERNIGHT...ESPECIALLY FROM MONARCH PASS NORTHWARD. CURRENT SNOWFALL
FORECAST IN THE 5 TO 9 INCH RANGE LOOKS ON TRACK...HIGHEST AMOUNTS
LIKELY NORTH OF COTTONWOOD PASS. SURFACE COLD FRONT DROPPING
QUICKLY SOUTH THROUGH WYOMING AS OF 22Z...AND WILL MOVE RAPIDLY
SOUTH ACROSS EASTERN COLORADO THIS EVENING. NORTH WINDS FOLLOWING
THE FROPA WILL GUST IN THE 45-55 MPH RANGE...AS STRONG SURFACE
PRESSURE RISE CENTER DROPS INTO THE REGION 06-09Z. MAY BE A QUICK
BURST OF -SHRA/-SHSN BEHIND THE FRONT OVER THE EASTERN MOUNTAINS AND
PLAINS...WITH THE BEST CHANCE OF PRECIP NORTH OF THE ARKANSAS RIVER
AND EAST OF THE I-25 CORRIDOR. NOT LOOKING FOR MUCH IF ANY
ACCUMULATING SNOW...THOUGH VISIBILITY COULD FALL BELOW A MILE
FOR A BRIEF PERIOD UNDER THE HEAVIER SHOWERS. ANY PRECIP WILL
QUICKLY EXIT THE AREA THURSDAY MORNING...AND ONLY A FEW -SHSN WILL
BE FOUND LINGERING OVER THE CENTRAL MOUNTAINS BY AFTERNOON. STRONG
N-NW WINDS WILL CONTINUE MOST LOCATIONS THROUGH THE DAY...THOUGH
I-25 CORRIDOR WILL LIKELY SEE SOME DECREASE IN SPEEDS BY MID/LATE
AFTERNOON. MODEL RH FORECASTS KEEP ALL OF THE PLAINS ABOVE 15
PERCENT THRESHOLD FOR A FIRE WX HIGHLIGHT...BUT GIVEN ATROCIOUS
DEWPOINT FORECASTS OF LATE...EXPECT DRIEST AREAS ALONG THE NM BORDER
TO BECOME DRY ENOUGH TO WARRANT A RED FLAG WARNING...WHILE AREA
FARTHER NORTH LOOKS TOO COOL TO FORCE RH LOW ENOUGH. MAX TEMPS MOST
LOCATIONS SHOULD FALL 15-20F VERSUS WED MAXES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 333 PM MST WED FEB 19 2014
THURSDAY NIGHT AND FRIDAY...BRISK NW FLOW ALOFT WILL KEEP SCATTERED
OR EVEN LIKELY POPS FOR THE CENTRAL MTS IN PLACE THROUGH THU
NIGHT...THEN AS THE FLOW SHIFTS TO A MORE WESTERLY DIRECTION PCPN
CHANCES ARE EXPECTED TO DROP OFF THROUGH FRI. STRONG DOWNSLOPE FLOW
IS FORECAST TO BOOST MAX TEMPS FOR THE PLAINS INTO THE MID 50S TO
AROUND 60 F. GFS AND EC MODELS PAINT A COLD FRONT DROPPING DOWN THE
EASTERN HALF OF THE STATE LATE FRI EVE. THIS WILL SET UP THE REGION
FOR A COOLER SAT.
SATURDAY AND SUNDAY...A REINFORCING PUSH OF LLVL UPSLOPE FLOW WILL
KEEP COOLER AIR IN PLACE FOR THE PLAINS...AS WELL AS BRING ISOLATED
SNOW POPS TO THE PALMER DVD AND FAR EASTERN PLAINS BY SAT AFTN AND
EVE. MEANWHILE...ISOLATED TO SCATTERED POPS CONTINUE FOR THE CENTRAL
MTS. FOR SUN...THE COOL AIR REMAINS IN PLACE FOR MAC TEMPS IN THE
30S AND 40S FOR THE CWA...BUT IT LOOKS LIKE IT MIGHT REMAIN DRY FOR
ALL AREAS WITH WESTERLY FLOW ALOFT.
MONDAY THROUGH WEDNESDAY...NW FLOW ALOFT CONTINUES WITH A CONTINUED
ISOLATED THREAT OF SNOW FOR THE CENTRAL MTS. MODELS ARE INDICATING A
DRY COLD FRONT MONDAY EVE WHICH WOULD COOL MAX TEMPS FOR TUE.
OTHERWISE...ISOLATED SNOW FOR THE HIGHER ELEVATIONS OF LAKE AND
CHAFFEE COUNTIES...WHILE DRY AND WARMER FOR THE REMAINDER OF THE
FORECAST AREA. MOORE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1019 PM MST WED FEB 19 2014
MAIN CONCERN WILL BE SN SHWRS...WHICH WILL BE THE MOST WIDESPREAD
OVR THE NEXT FEW HOURS...AND COULD RESULT IN BRIEF IFR CONDITIONS
ESPECIALLY THRU 09Z. BANDED SN SHWRS WILL MOVE TO THE S WITH THE
COLD FRONT THRU THU MORNING...SO EXPECT IMPROVING CONDITIONS AT
KCOS AFTER 09-10Z AND AT KPUB AN HOUR OR TWO LATER. ONLY SPOTTY
ISOLD SHWRS EXPECTED AT ALS...WHICH SHOULD BE VFR FOR THU.
COULD BE A FEW SHOWERS AND LOCALIZED LOW CIGS THRU ABOUT 12Z E OF
THE MTS. WINDS WILL CONTINUE TO GUST FROM THE N TO NW BEHIND THE
FRONT. THERE COULD BE A BRIEF LULL IN THE WINDS EARLY THU...BUT WINDS
SHOULD INCREASE AGAIN FROM THE NW IN THE 16Z TO 23Z TIME FRAME...AND
THERE COULD BE A FEW GUSTS IN THE 40 KT RANGE DURING THIS TIME.
WINDS WILL RELAX THU EVENING. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM MST THURSDAY FOR COZ081-082-
084.
RED FLAG WARNING FROM 11 AM TO 6 PM MST THURSDAY FOR COZ229-230-
233-237.
WINTER WEATHER ADVISORY UNTIL 8 AM MST THURSDAY FOR COZ058-060.
&&
$$
UPDATE...LW
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1026 PM MST WED FEB 19 2014
.UPDATE...
ISSUED AT 850 PM MST WED FEB 19 2014
ADDING SNOW/BLOWING SNOW ADVISORY TO TELLER/NORTHERN EL PASO COUNTIES
FOR THE REST OF TONIGHT...BASED ON RADAR/SATELLITE TRENDS AND HI RES
MODEL FORECASTS FOR THE REMAINDER OF THE NIGHT. HRRR DEVELOPS GOOD
PERIOD OF SNOW/BLOWING SNOW ACROSS TELLER/MAINLY NORTHERN EL PASO
COUNTIES SHORTLY AND THEN CONTINUING FOR SEVERAL HOURS BEFORE
ENDING. ADVISORY AND UPDATED PRODUCTS WILL BE OUT SHORTLY. LW
UPDATE ISSUED AT 701 PM MST WED FEB 19 2014
LOADED LATEST OBSERVATIONS AND BLENDED INTO FORECAST. ADJUSTED
SKY COVER AND PRECIP GRIDS TO REFLECT LATEST RADAR AND SATELLITE
TRENDS...AS WELL AS SHORT TERM HI RES MODEL FORECASTS. LW
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 333 PM MST WED FEB 19 2014
STRONG UPPER TROUGH MOVING QUICKLY EASTWARD THROUGH THE GREAT BASIN
INTO WESTERN COLORADO THIS AFTERNOON...WITH SNOW DEVELOPING AND EVEN
A COUPLE LIGHTNING STRIKES WEST OF THE CONTINENTAL DIVIDE THIS
AFTERNOON. EXPECT SNOW TO BEGIN BY SUNSET OVER THE CENTRAL AND
SOUTHWEST MOUNTAINS...WITH A PERIOD OF HEAVY SNOW AND BLOWING SNOW
OVERNIGHT...ESPECIALLY FROM MONARCH PASS NORTHWARD. CURRENT SNOWFALL
FORECAST IN THE 5 TO 9 INCH RANGE LOOKS ON TRACK...HIGHEST AMOUNTS
LIKELY NORTH OF COTTONWOOD PASS. SURFACE COLD FRONT DROPPING
QUICKLY SOUTH THROUGH WYOMING AS OF 22Z...AND WILL MOVE RAPIDLY
SOUTH ACROSS EASTERN COLORADO THIS EVENING. NORTH WINDS FOLLOWING
THE FROPA WILL GUST IN THE 45-55 MPH RANGE...AS STRONG SURFACE
PRESSURE RISE CENTER DROPS INTO THE REGION 06-09Z. MAY BE A QUICK
BURST OF -SHRA/-SHSN BEHIND THE FRONT OVER THE EASTERN MOUNTAINS AND
PLAINS...WITH THE BEST CHANCE OF PRECIP NORTH OF THE ARKANSAS RIVER
AND EAST OF THE I-25 CORRIDOR. NOT LOOKING FOR MUCH IF ANY
ACCUMULATING SNOW...THOUGH VISIBILITY COULD FALL BELOW A MILE
FOR A BRIEF PERIOD UNDER THE HEAVIER SHOWERS. ANY PRECIP WILL
QUICKLY EXIT THE AREA THURSDAY MORNING...AND ONLY A FEW -SHSN WILL
BE FOUND LINGERING OVER THE CENTRAL MOUNTAINS BY AFTERNOON. STRONG
N-NW WINDS WILL CONTINUE MOST LOCATIONS THROUGH THE DAY...THOUGH
I-25 CORRIDOR WILL LIKELY SEE SOME DECREASE IN SPEEDS BY MID/LATE
AFTERNOON. MODEL RH FORECASTS KEEP ALL OF THE PLAINS ABOVE 15
PERCENT THRESHOLD FOR A FIRE WX HIGHLIGHT...BUT GIVEN ATROCIOUS
DEWPOINT FORECASTS OF LATE...EXPECT DRIEST AREAS ALONG THE NM BORDER
TO BECOME DRY ENOUGH TO WARRANT A RED FLAG WARNING...WHILE AREA
FARTHER NORTH LOOKS TOO COOL TO FORCE RH LOW ENOUGH. MAX TEMPS MOST
LOCATIONS SHOULD FALL 15-20F VERSUS WED MAXES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 333 PM MST WED FEB 19 2014
THURSDAY NIGHT AND FRIDAY...BRISK NW FLOW ALOFT WILL KEEP SCATTERED
OR EVEN LIKELY POPS FOR THE CENTRAL MTS IN PLACE THROUGH THU
NIGHT...THEN AS THE FLOW SHIFTS TO A MORE WESTERLY DIRECTION PCPN
CHANCES ARE EXPECTED TO DROP OFF THROUGH FRI. STRONG DOWNSLOPE FLOW
IS FORECAST TO BOOST MAX TEMPS FOR THE PLAINS INTO THE MID 50S TO
AROUND 60 F. GFS AND EC MODELS PAINT A COLD FRONT DROPPING DOWN THE
EASTERN HALF OF THE STATE LATE FRI EVE. THIS WILL SET UP THE REGION
FOR A COOLER SAT.
SATURDAY AND SUNDAY...A REINFORCING PUSH OF LLVL UPSLOPE FLOW WILL
KEEP COOLER AIR IN PLACE FOR THE PLAINS...AS WELL AS BRING ISOLATED
SNOW POPS TO THE PALMER DVD AND FAR EASTERN PLAINS BY SAT AFTN AND
EVE. MEANWHILE...ISOLATED TO SCATTERED POPS CONTINUE FOR THE CENTRAL
MTS. FOR SUN...THE COOL AIR REMAINS IN PLACE FOR MAC TEMPS IN THE
30S AND 40S FOR THE CWA...BUT IT LOOKS LIKE IT MIGHT REMAIN DRY FOR
ALL AREAS WITH WESTERLY FLOW ALOFT.
MONDAY THROUGH WEDNESDAY...NW FLOW ALOFT CONTINUES WITH A CONTINUED
ISOLATED THREAT OF SNOW FOR THE CENTRAL MTS. MODELS ARE INDICATING A
DRY COLD FRONT MONDAY EVE WHICH WOULD COOL MAX TEMPS FOR TUE.
OTHERWISE...ISOLATED SNOW FOR THE HIGHER ELEVATIONS OF LAKE AND
CHAFFEE COUNTIES...WHILE DRY AND WARMER FOR THE REMAINDER OF THE
FORECAST AREA. MOORE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1019 PM MST WED FEB 19 2014
MAIN CONCERN WILL BE SN SHWRS...WHICH WILL BE THE MOST WIDESPREAD
OVR THE NEXT FEW HOURS...AND COULD RESULT IN BRIEF IFR CONDITIONS
ESPECIALLY THRU 09Z. BANDED SN SHWRS WILL MOVE TO THE S WITH THE
COLD FRONT THRU THU MORNING...SO EXPECT IMPROVING CONDITIONS AT
KCOS AFTER 09-10Z AND AT KPUB AN HOUR OR TWO LATER. ONLY SPOTTY
ISOLD SHWRS EXPECTED AT ALS...WHICH SHOULD BE VFR FOR THU.
COULD BE A FEW SHOWERS AND LOCALIZED LOW CIGS THRU ABOUT 12Z E OF
THE MTS. WINDS WILL CONTINUE TO GUST FROM THE N TO NW BEHIND THE
FRONT. THERE COULD BE A BRIEF LULL IN THE WINDS EARLY THU...BUT WINDS
SHOULD INCREASE AGAIN FROM THE NW IN THE 16Z TO 23Z TIME FRAME...AND
THERE COULD BE A FEW GUSTS IN THE 40 KT RANGE DURING THIS TIME.
WINDS WILL RELAX THU EVENING. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM MST THURSDAY FOR COZ081-082-
084.
RED FLAG WARNING FROM 11 AM TO 6 PM MST THURSDAY FOR COZ229-230-
233-237.
WINTER WEATHER ADVISORY UNTIL 8 AM MST THURSDAY FOR COZ058-060.
&&
$$
UPDATE...LW
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1213 AM CST THU FEB 20 2014
.DISCUSSION...
918 PM CST
EVENING UPDATE...
KEY UPDATE THIS EVENING IS THAT WE WILL BE HOISTING A HIGH WIND
WATCH FOR THE ENTIRE AREA STARTING AT 00Z TOMORROW EVENING.
INTENSE WARM ADVECTION DRIVEN PRECIP CURRENTLY ACROSS SOUTHERN IA
AND NORTHERN MO AHEAD OF DEVELOPING SURFACE LOW OVER CENTRAL
PLAINS WILL OVERSPREAD AREA LATE TONIGHT. BIGGEST CONCERN IS WITH
SURFACE TEMPERATURES ESPECIALLY NORTH OF INTERSTATE 80 AND ALSO
TEMPERATURES ALOFT DUE TO EVAPORATIONAL/DYNAMIC COOLING MAINLY
ALONG/NORTH OF I-88 AS PRECIP BEGINS. SURFACE WET BULB 0 VALUES
WITH DEWPOINTS CURRENTLY IN THE 20S NORTH OF I-80 WILL BE AT OR
BELOW FREEZING UNTIL 12Z OR SO WE ADDED IN FREEZING MENTION ALONG
I-80 CORRIDOR. STRONG WARM SURGE WITH H8 TEMPS WARMING TO +6 OR
+7C FROM SOUTH SHOULD AID IN WARMING ENTIRE COLUMN ABOVE FREEZING
BY DAYBREAK. FARTHER NORTH/ALONG NORTH OF I-88...DRY EAST FLOW
ALOFT WILL CAUSE COLUMN TO COOL TO OR BELOW FREEZING AS IT TRIES
TO SATURATE. THUS THERE COULD BE A BURST OF ACCUMULATING
SNOW/SLEET...FOLLOWED BY TRANSITION TO ZR AND THEN PLAIN RAIN BY
14 TO 15Z TOMORROW. WOULD EXPECT IMMEDIATE DOWNTOWN CHICAGO TO BE
AT LESS OF A THREAT OF SNOW AND BRIEF ICE ACCUMS DUE TO VERY MILD
TEMPS THE PAST FEW DAYS. SURFACE TEMPS WILL NEED TO BE MONITORED
CLOSELY REGARDING POTENTIAL FOR ZR TO HOLD ON A BIT LONGER IN
PARTS OF FAR NORTHERN IL TOMORROW AM. WILL CONTINUE WITH SPS FOR
SNOW/ICE THREAT.
STILL ON TRACK FOR RAPID WARM UP TOMORROW AFTERNOON...WHICH COULD
RESULT IN AREAS OF DENSE FOG BUT MORE IMPORTANTLY ACCELERATE
SNOWMELT ON TOP OF WHAT OCCURRED WITH THE HEAVY RAIN IN THE AM.
THUS HAVE MADE NO CHANGES TO FLOOD WATCH. ISOLATED TSRA ARE
POSSIBLE IN STEEP MIDLEVEL LAPSE RATES UNDER DRY SLOT OF
INTENSIFYING CYCLONE.
FINALLY...REGARDING WINDS...VERY IMPRESSIVE SET-UP AS LOW LIFTS TO
SOUTHERN WI TOMORROW EVENING SWINGING POWERFUL COLD FRONT THROUGH
AREA. VERY SHARP CAA AND STRONG ISALLOBARIC PRESSURE RISES WILL
MAKE IT MUCH EASIER TO TAP INTO 50+ KT WINDS AT TOP OF THE
CHANNEL. SUSTAINED WESTERLY WIND SPEEDS COULD ALSO BE UP TO 30 KT.
THUS WITH POTENTIAL FOR 50+ KT GUSTS AND 30+ KT SUSTAINED
SPEEDS...WILL HOIST HIGH WIND WATCH FOR ENTIRE CWA STARTING 00Z
THURSDAY EVENING. WATCH ENDS A BIT EARLIER IN THE FAR SOUTH WHERE
WINDS MAY DIMINISH SLIGHTLY SOONER...BUT GOES TO 12Z FRIDAY FOR
MOST OF THE AREA.
RC
//PREV DISCUSSION...
303 PM CST
SHORT TERM...TONIGHT THROUGH THURSDAY PM...
A VERY DYNAMIC AND COMPLEX STORM SYSTEM WILL IMPACT THE AREA LATE
TONIGHT THROUGH THURSDAY EVENING. THIS WILL PRESENT A PLETHORA OF
FORECAST CONCERNS OVER THE NEXT 24 TO 36 HOURS. THESE INCLUDE:
1.) THE THREAT FOR ACCUMULATING SNOW AND ICE AT THE ONSET OVERNIGHT
TONIGHT...PARTICULARLY ACROSS FAR NORTHERN ILLINOIS ALONG AND NORTH
OF INTERSTATE 88.
2.)RAINFALL AMOUNTS AND HYDRO ISSUES ON THURSDAY.
3.)POTENTIAL FOR SOME STRONG THUNDERSTORMS THURSDAY AFTERNOON.
4.)POTENTIAL FOR AREAS OF FOG ON THURSDAY.
5.)THE SYNOPTIC WINDS ON THE BACK SIDE OF THE SYSTEM LATE THURSDAY
AFTERNOON AND INTO THURSDAY NIGHT.
THE 12 UTC GLOBAL MODELS HAVE THE BEST HANDLE ON THE EVOLUTION AND
TRACK OF THIS STORM SYSTEM OVER THE NEXT 36 HOURS. AS SUCH...THE 12
UTC NAM WAS A FAR EAST OUTLIER ON THE SURFACE LOW TRACK. IN MOST
CASES...THE 12 UTC NAM WAS A GOOD 100 TO 150 MILES EAST OF THE
GLOBAL MODELS AND ENSEMBLE SOLUTIONS...SO THE 12 UTC NAM WAS NOT
FOLLOWED.
OVERALL...CYCLOGENESIS WILL SET UP ACROSS THE FRONT RANGE OF THE
COLORADO ROCKIES THIS EVENING IN ASSOCIATION WITH A STOUT SHORT WAVE
DISTURBANCE...NOW PUSHING ACROSS THE INTER-MOUNTAIN WEST. THIS WILL
RESULT IN A SURFACE LOW AROUND 992 MB...WHICH SHOULD PUSH EASTWARD
ACROSS THE KANSAS OKLAHOMA STATE LINE OVERNIGHT. THE MID LEVEL
SYSTEM WILL BE FORCED TO BECOME NEGATIVELY TILTED AS IT ENCOUNTERS
RAPIDLY BUILDING HIGHS ACROSS THE GREAT LAKES REGION EARLY THURSDAY.
AS A RESULT...THE SURFACE LOW WILL DEVELOP EXPLOSIVELY...WITH THE
CENTRAL PRESSURE EXPECTED TO DROP NEARLY 12 MB IN 12 HOURS AS THE
LOW LIFTS NORTHEASTWARD TO SOUTHEASTERN WISCONSIN BY EARLY THURSDAY
EVENING. THE LOW WILL LIKELY CONTINUE DEEPENING TO AROUND 970 MB BY
FRIDAY MORNING AS IT MOVES ACROSS THE UPPER GREAT LAKES REGION.
THE RAPID DEEPENING OF THE CENTRAL PRESSURE OF THIS LOW ALONE SAYS
THAT THIS WILL BE A NOTABLE WEATHER MAKER FOR MUCH OF THE CENTRAL
CONUS. PRECIPITATION WILL LIKELY ONSET QUICKLY ACROSS MOST OF
ILLINOIS AND INTO INDIANA TONIGHT AFTER 1 OR 2 IN THE MORNING AS 45
TO 50 KT LOW LEVEL JET DEVELOPS AND NOSES INTO THE REGION. THIS WILL
SET UP A VERY IMPRESSIVE SURGE OF GULF MOISTURE...WITH PWATS QUICKLY
INCREASING FROM ONLY A TENTH OR TWO OF AN INCH...TWO AROUND 1 INCH
BY DAYBREAK THURSDAY. CLIMATOLOGICALLY SPEAKING...1 INCH PWATS THIS
TIME OF YEAR RANK IN THE 99 TH PERCENTILE...SO HEAVY RAINFALL WILL
DEFINITELY BE A CONCERN. FOR MORE INFO ON THE HYDRO...SEE THE HYDRO
DISCUSSION BELOW.
THERE CONTINUES TO BE CONCERNS OF A WINTER MIX OF SNOW...FREEZING
RAIN AND SLEET AT THE ONSET OF THE PRECIPITATION
OVERNIGHT...PARTICULARLY AREAS ALONG AND NORTH OF INTERSTATE 88. IT
APPEARS THAT STRONG DYNAMIC FORCING WILL SET UP ALONG THE NOSE OF
THE LOW LEVEL JET...AND THIS STRONG FORCING COMBINED WITH
EVAPORATION COOLING COULD RESULT IN A COLUMN COLD ENOUGH FOR ALL
SNOW...ESPECIALLY CLOSER TO THE WISCONSIN BOARDER. THIS COULD RESULT
IN A PERIOD OF MODERATE TO HEAVY SNOW AND SLEET ACROSS FAR NORTHERN
ILLINOIS TONIGHT INTO VERY EARLY THURSDAY MORNING BEFORE THE WARM
SURGE KICKS NORTHWARD...CHANGING EVERYTHING OVER TO LIQUID. MODEL
BUFFER SOUNDINGS ACROSS THIS REGION ARE VERY CONCERNING...WITH THE
PROFILES INDICATING A NEARLY ISOTHERMAL LAYER FROM THE SURFACE UP TO
AROUND 700 MB HUGGING THE FREEZING POINT...AND VERY STEEP MID LEVEL
LAPSE RATES ABOVE THIS ISOTHERMAL LAYER. SO ALTHOUGH THERE MAY ONLY
BE A COUPLE HOUR PERIOD SUPPORTIVE OF SNOW...SLEET AND FREEZING
RAIN...THERE COULD BE A FEW INCHES OF SNOW ACCUMULATION AND A FEW
HUNDREDTHS OF AN INCH OF ICE ACCUMULATION FAR NORTH PRIOR TO THE
CHANGE OVER TO RAIN...ESPECIALLY WITH ANY CONVECTIVE ELEMENTS.
CONFIDENCE REMAINS LOW...BUT I HAVE ADDED SOME SNOW AND ICE
ACCUMULATIONS INTO THE FORECAST...WITH THE POTENTIAL OF SOME RAPID
SNOW ACCUMULATIONS. I WILL HIGHLIGHT THIS THREAT IN AN SPS...AND
PASS ALONG THE CONCERNS TO THE EVENING SHIFT TO SEE IF ANY WINTER WX
HEADLINE WILL BE NEEDED.
ANY WINTER PRECIP WILL QUICKLY COME TO AN END EARLY THURSDAY
MORNING...WITH PERIODS OF RAIN AND THUNDERSTORMS THROUGH THE
REMAINDER OF THE MORNING AS THE WARM FRONT SHIFTS ACROSS NORTHERN
ILLINOIS. IN ADDITION TO THE THUNDERSTORMS AND HEAVY RAIN
POTENTIAL...THERE IS A THREAT OF FOG...ESPECIALLY IN THE VICINITY
OF THE WARM FRONT AND SURFACE LOW. A STRONG COLD FRONT WILL BEGIN TO
PUSH ACROSS THE AREA DURING THE AFTERNOON...AND THIS LOOKS TO BE THE
FOCUS FOR A LINE OF STORMS. IT CURRENTLY APPEARS THE BETTER THREAT
FOR MORE WIDESPREAD SEVERE STORMS WILL BE SOUTH OF THE AREA. THE
EXTENSIVE SNOW PACK ACROSS THE AREA MAY RESULT IN A NEAR SURFACE
INVERSION THAT MAY KEEP THE STORMS FROM ROOTING THEMSELVES IN THE
BOUNDARY LAYER. BECAUSE OF THIS...ALTHOUGH THE WINDS WILL BE
SCREAMING UP OVER 50 KT OFF THE SURFACE...THEY MAY HAVE A HARD TIME
BEING FORCED TO THE GROUND WITH THE STORMS. THEREFORE...ALTHOUGH
SOME ISOLATED SEVERE WIND GUSTS ARE POSSIBLE WITH THESE AFTERNOON
SHOWERS/STORMS...IT APPEARS THE MORE WIDESPREAD ACTIVITY WILL REMAIN
SOUTH OF MUCH OF THE AREA.
A DRY MID LEVEL DRY SLOT WILL PUSH IN ACROSS THE AREA BY EARLY
THURSDAY EVENING...AND THIS SHOULD BRING AN END TO THE
PRECIP...WITH THE EXCEPTION OF FAR NORTH CENTRAL ILLINOIS...WHERE
SOME RAP AROUND SNOW SHOWERS ARE POSSIBLE IN ASSOCIATION WITH THE
MID LEVEL DEFORMATION ZONE.
THE MAIN STORY THURSDAY EVENING...HOWEVER...WILL BE THE STRONG
SYNOPTIC WINDS IN THE WAKE OF THE COLD FRONT. THE TRACK OF THE
SURFACE LOW WILL PLACE NORTHERN ILLINOIS/NORTHWESTERN INDIANA IN A
VERY FAVORABLE LOCATION FOR VERY STRONG SYNOPTIC WINDS THURSDAY
EVENING. ISOBARIC PRESSURE RISES ON THE ORDER OF 14+ MB IN A 6 HOUR
PERIOD ARE EXPECTED TO OVERSPREAD THE AREA. THIS COULD LEAD TO TOP
OF THE CHANNEL TYPE MIXING FOR A FEW HOURS FOLLOWING THE THE COLD
FRONTAL PASSAGE EARLY THURSDAY EVENING. AS SUCH...THIS COULD LEAD TO
50+ KT WIND GUSTS ACROSS THE AREA FOR A PERIOD THURSDAY EVENING. IN
SPITE OF THIS...I WILL LET THE OVERNIGHT SHIFT GET ANOTHER LOOK AT
THIS POTENTIAL TO SEE IF EITHER A WIND ADVISORY OR HIGH WIND
WARNING WILL BE NEEDED FOR THIS PERIOD.
KJB
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...
300 PM...STRONG LOW PRESSURE OVER WISCONSIN WILL CONTINUE TO
DEEPEN THURSDAY NIGHT AS IT LIFTS NORTH TO LAKE SUPERIOR. THE
GRADIENT WILL REMAIN TIGHT THROUGH FRIDAY AFTERNOON WITH WESTERLY
WINDS 20-30 MPH WITH HIGHER GUSTS INTO THE 40 MPH RANGE. THERE
REMAINS A SMALL POTENTIAL FOR LIGHT SNOW OR SNOW SHOWERS LATE
THURSDAY NIGHT INTO EARLY FRIDAY MORNING MAINLY ACROSS THE NORTH
HALF/THIRD OF THE CWA. ANY AMOUNTS WILL BE LIGHT BUT WITH THE
CONTINUED STRONG WINDS...ANY FRESH SNOW WILL LIKELY CAUSE SOME
BLOWING/DRIFTING SNOW.
A WEAKER COLD FRONT/TROUGH WILL PASS ACROSS THE REGION FRIDAY
EVENING...BRINGING ANOTHER CHANCE OF LIGHT SNOW/SNOW SHOWERS AND
HAVE ADDED THIS TO THE FORECAST...BUT PRIOR TO ITS ARRIVAL...WEAK
WARM AIR ADVECTION WILL SPREAD ACROSS THE AREA WITH AT LEAST SOME
SUNSHINE THROUGH MIDDAY. HAVE BUMPED HIGH TEMPS UP A TAD INTO THE
MID/UPPER 30S ACROSS MUCH OF THE CWA BUT THIS IS STILL A FEW
DEGREES BELOW CURRENT GUIDANCE LEVELS AND MAY END UP BEING TOO
COOL.
COLDER AIR THEN SPREADS BACK ACROSS THE REGION THIS WEEKEND WITH
BELOW NORMAL/MUCH COLDER TEMPERATURES THROUGH THE MIDDLE OF NEXT
WEEK WITH HIGHS GENERALLY IN THE 20S AND LOWS IN THE SINGLE DIGITS.
ECMWF/GFS HAVE BEEN SOMEWHAT CONSISTENT WITH A CLIPPER LIKE SYSTEM
MOVING ACROSS THE AREA MONDAY NIGHT WITH A TENTH OR TWO OF QPF.
THIS COULD EASILY FLUFF UP A FEW INCHES OF SNOW. HAVE MAINTAINED
GOING CHANCE POPS AS THE TREND HAS BEEN FOR IT TO SAG A LITTLE
FURTHER SOUTH AND PERHAPS AFFECT ONLY THE SOUTHERN PART OF THE CWA.
MODELS THAN DIFFER ON JUST HOW COLD THE NEXT PUNCH OF ARCTIC AIR
WILL BE WHEN IT ARRIVES WEDNESDAY/WEDNESDAY NIGHT. CMS
&&
.HYDROLOGY...
330 PM CST...THE STRONG LATE WINTER STORM SYSTEM IS EXPECTED TO
BRING CONDITIONS THAT WOULD BE CONDUCIVE TO THE POTENTIAL FOR
WIDESPREAD AREAL AND RIVER FLOODING TO NORTHERN ILLINOIS AND
NORTHWEST INDIANA.
PRECIPITATION IS EXPECTED TO BEGIN DURING THE EARLY MORNING HOURS
AND WILL INITIALLY BE A WINTRY MIX WITH LIGHT QPF AMOUNTS. THROUGH
THE MORNING AND INTO THE AFTERNOON...AS THE MAIN SFC LOW DEEPENS...
THE ASSOCIATED WARM FRONT WILL SURGE NORTH INTO WISCONSIN AND SET
UP A PERSISTENT FETCH OF WARM...MOIST AIR FROM A WIDE OPEN WESTERN
GLFMEX REGION. CURRENT INDICATORS SUGGEST THAT TEMPERATURES WILL
SURGE INTO THE UPPER 40S NEAR THE WISCONSIN BORDER TO THE MIDDLE
50S SOUTH OF THE ILLINOIS AND KANKAKEE RIVER VALLEYS. SFC
DEWPOINTS WILL ALSO SURGE INTO THE MIDDLE 40S TO AROUND 50F. THE
MODEL GUIDANCE SUGGESTS THAT PRECIPITABLE WATER VALUES WILL
APPROACH 1 INCH TOMORROW...WHICH IS AT LEAST 2 STANDARD DEVIATIONS
HIGHER THAN NORMAL FOR LATE FEBRUARY. THE HIGH PRECIPITABLE WATER
VALUES AND THE DYNAMIC SYSTEM ARE INDICATIVE THAT THE POTENTIAL
FOR A SIGNIFICANT AMOUNT OF LIQUID PRECIPITATION...WITH THE
CURRENT FORECAST CARRYING 0.75 TO 1.00 INCHES FOR THE PERIOD
FROM 09Z THURSDAY THROUGH 00Z FRIDAY. THE HEAVY RAIN WILL HAVE AN
IMPACT ON BOTH AREAL FLOOD AND RIVER FLOOD CONCERNS.
THE WARM...HIGH DEWPOINT AIR IS VERY EFFICIENT AT MELTING SNOW
AND...CURRENTLY...THERE IS 2 TO 4 INCHES OF LIQUID EQUIVALENT
TRAPPED IN THE SNOW PACK. THIS...COMBINED WITH AROUND 1 INCH OF
WIDESPREAD QPF...WOULD GIVE A WORST CASE SCENARIO OF 3 TO 5 INCHES
OF RAINFALL. HOWEVER...THERE ARE LIMITING AND COMPLICATING FACTORS
WHICH NEED TO PLAY OUT...WHICH WOULD ACT TO EITHER LIMIT THE FLOOD
POTENTIAL OR ENHANCE THE FLOOD POTENTIAL...ESPECIALLY FOR AREA
RIVERS. CURRENTLY...MOST AREA RIVERS AND STREAMS ARE EITHER TOTALLY
ICE COVERED OR ONLY HAVE VERY LIMITED AMOUNTS OF OPEN WATER...SINCE
THIS WINTER HAS SEEN AN UNUSUAL DEGREE OF EXTREME COLD. EVEN THE
ILLINOIS RIVER HAS MUCH MORE ICE COVERAGE THAN IS NORMALLY OBSERVED
IN A TYPICAL WINTER. HEAVY RAINFALL AND ICE COVERED RIVERS WILL
HAVE A TWO-FOLD IMPACT. THE CAPACITY OF ICE COVERED RIVERS IS MUCH
LOWER THAN OPEN RIVERS WITH THE RAIN COLLECTING ON TOP OF THE ICE AS
IT IT WERE A RIVER BED. SO...LESS RAINFALL WOULD BE NEEDED TO RAISE
WATER LEVELS ABOVE BANK FULL AND TO FLOOD STAGE. ALSO...THE RAINFALL
WILL INCREASE BASE FLOW AND INFILTRATION OF RAINFALL INTO THE
RIVERS...LEADING TO INCREASED STREAM FLOW RATES...INCREASING
HYDROSTATIC PRESSURE UNDER THE ICE...WHICH COULD THEN LEAD TO ICE
BREAKUP AND ICE JAM FLOODING. ANY ICE JAM FLOODING WOULD ONLY
COMPOUND ANY RIVER FLOODING CAUSED BY THE RAINFALL RUNNING OFF ON
TOP OF THE ICE. HOWEVER...SINCE THE FROST DEPTH IS AROUND 14 INCHES
ACROSS THE AREA...IT IS UNLIKELY THAT THE INFLUX OF WARM AIR AND
RAIN WILL HAVE A SIGNIFICANT IMPACT ON THE FROST DEPTH. SO...ANY
MELTING AND RAINFALL WILL LIKELY MOSTLY BECOME RUNOFF...RATHER THAN
BEING INCORPORATED INTO INCREASED BASE FLOW...SO THERE IS LESS OF A
THREAT FOR WIDESPREAD BREAKUP OF THE THICKER ICE. BUT THE
POSSIBILITY OF ICE BREAKUP AND ICE JAM FLOODING CAN NOT BE RULED OUT
FOR RIVERS WITH THINNER ICE COVERAGE. THERE IS ALSO SOME
UNCERTAINTY AS TO THE DEGREE OF SNOW MELT THAT CAN BE EXPECTED AND
THE ASSOCIATED IMPACT ON RIVER LEVELS. CURRENTLY...THE RIVER STAGE
MODELS HAVE BEEN RUN WITH THE PREMISE THAT THE SNOW PACK WILL NOT
COMPLETELY MELT...ESPECIALLY FOR THE NORTHERN PORTIONS OF THE CWA
WHICH HAVE A DEEPER SNOW PACK AND SHOULD BE COLDER FOR A LONGER
PERIOD OF TIME. THERE IS ALSO THE CONSIDERATION THAT THE SNOW PACK
WILL ABSORB SOME OF THE RAINFALL BEFORE IT IS CONVERTED INTO
RUNOFF. SO...ALL THINGS CONSIDERED...THERE WILL BE A SIGNIFICANT
CHANCE FOR RIVER FLOODING WITH MANY RIVERS REACHING OR EXCEEDING
BANK FULL...BUT MAJOR OR RECORD BREAKING RIVER STAGES IS NOT LIKELY.
FOR AREAL FLOODING...THE MAIN CONTRIBUTORS WILL BE THE HEAVY
RAINFALL AND MELTING SNOW. AGAIN...WITH THE FROST DEPTH OF 14
INCHES...IT IS UNLIKELY THAT THERE WILL BE SIGNIFICANT INFILTRATION
INTO THE GROUND AND SNOW MELT AND RAINFALL WILL COMBINE INTO RUNOFF.
HOWEVER...SIMILAR TO THE RIVER ISSUES...IT WILL BE TOUGH FOR ALL OF
THE SNOW PACK TO MELT AND SOME OF THE RAINFALL COULD BECOME TRAPPED
IN THE RESIDUAL SNOW PACK...WHICH WOULD IN TURN LOWER THE RUNOFF.
AT THIS POINT...FEEL THAT AREAL FLOODING WILL BE LIMITED TO FLOODING
OF LOW LYING AREAS...UNDERPASSES AND DITCHES ADJACENT TO ROADS.
ALSO...URBAN AND SUBURBAN AREAS COULD SEE WIDESPREAD AREAS OF
PONDING AND STANDING WATER DUE TO SNOW-CLOGGED STORM DRAINS.
FOR THE HEADLINES...WILL MAINTAIN THE GOING FLOOD WATCH AND MONITOR
CONDITIONS BEFORE EITHER GOING WITH A FLOOD WARNING OR AN URBAN AND
SMALL STREAM FLOOD ADVISORY. AS FOR AREA RIVERS...WILL WAIT UNTIL
THE NEXT MODEL RUNS FROM THE NCRFC BEFORE DECIDING ON HEADLINES FOR
AREA RIVERS. THE CURRENT RIVER FORECASTS DO CONSIDER THE
RAINFALL...BUT HAVE BEEN RUN WITH AN INITIAL CONDITION OF LIMITED
SNOW MELT. CHANGES IN THE INITIAL CONDITIONS FOR SNOW MELT AND QPF
WILL HAVE A SIGNIFICANT IMPACT ON THE RIVER STAGE FORECASTS.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* WINTRY MIX POSSIBLE AT PRECIP ONSET.
* RAIN AND THUNDER POSSIBLE THIS MORNING...AND POSSIBLE AGAIN IN
THE AFTERNOON.
* IFR/LIFR CEILINGS.
* STRONG TURNING WINDS.
RODRIGUEZ
//DISCUSSION...UPDATED 06Z...
COMPLEX FORECAST THIS PERIOD WITH SEVERAL ISSUES POSSIBLE TODAY
THROUGH TONIGHT. SYSTEM TO AFFECT THE REGION STILL APPROACHING AT
THIS TIME BUT REMAINING WEST/SOUTHWEST OF THE TERMINALS. THIS
SHOULD CHANGE OVER THE NEXT SEVERAL HOURS AS BETTER FORCING/PRECIP
SPREAD NORTHEAST ACROSS THE AREA. HAVE PRECIP REACHING THE
TERMINALS BY THE 9Z AND 10Z TIME WITH SOME POTENTIAL FOR A WINTRY
MIX OF SNOW/FREEZING RAIN/SLEET AT THE ONSET. ALTHOUGH WITH
SURFACE TEMPERATURES POSSIBLY HOLDING STEADY OR RISING
SLIGHTLY...THE MAIN THREAT COULD END UP ONLY BEING SNOW OR SLEET.
NONETHELESS...THIS WINTRY MIX SHOULD ONLY BE BRIEF BEFORE IT
BECOMES ALL RAIN SOON THERE AFTER. DID ALSO INCLUDE THE MENTION OF
VCTS IN THE TAFS BY 10Z AS STRONG FORCING AND AN INCREASE IN
INSTABILITY MOVE OVER THE TAFS. CONFIDENCE IS LOW WITH REGARDS TO
THE DURATION...BUT COULD EASILY SEE THUNDER TO BE IN AND AROUND
THE TERMINALS FOR A TWO TO THREE HOUR WINDOW. VFR CEILINGS SHOULD
QUICKLY COME DOWN TO LOW END MVFR AND IFR BY THE 12-13Z TIME
FRAME...AND THEN STAY DOWN WITH A TREND TOWARDS LIFR LIKELY.
PRECIP WILL LIKELY CONTINUE THROUGH THE DAY BUT REMAIN ALL
RAIN...WITH THUNDER POSSIBLE ONCE AGAIN IN THE AFTERNOON.
EXPECT SOUTHEAST WINDS TO BECOME MORE EASTERLY AND POSSIBLY
NORTHEAST LATER THIS MORNING...BEFORE TURNING BACK TOWARDS THE
SOUTHEAST AND SOUTH THIS AFTERNOON. WINDS WILL RAMP UP AND BECOME
STRONG IN THE LATE AFTERNOON AND EARLY EVENING...AS THEY TURN
SOUTHWEST.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE WITH PRECIP SPREADING ACROSS THE TERMINALS...LOW
MEDIUM CONFIDENCE WITH WINTRY MIX AT ONSET.
* MEDIUM CONFIDENCE WITH THUNDER TRENDS.
* HIGH CONFIDENCE WITH CEILING TRENDS.
* MEDIUM CONFIDENCE IN WIND DIRECTION/SPEED.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...CHC SNOW OVERNIGHT.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...CHC SNOW OVERNIGHT.
TUESDAY...VFR.
BMD
&&
.MARINE...
315 PM...LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS
TONIGHT AND DEEPEN AS IT MOVES TO SOUTHERN WISCONSIN THURSDAY
EVENING. THIS LOW WILL THEN CONTINUE TO DEEPEN AS IT REACHES LAKE
SUPERIOR FRIDAY MORNING. SOUTHERLY WINDS WILL TURN SOUTHEAST
TONIGHT AND GRADUALLY INCREASE OVERNIGHT THEN TURN A BIT MORE
EAST/SOUTHEAST THURSDAY AS SPEEDS INCREASE TO 30 KTS MIDDAY. AS
THE LOW APPROACHES...GALES WILL DEVELOP LATE THURSDAY AFTERNOON.
ONCE THE LOW REACHES WISCONSIN...WINDS WILL SHIFT TO THE SOUTHWEST
AND STEADILY INCREASE THROUGH HIGH END GALES AND POTENTIALLY INTO
STORM FORCE. HAVE UPGRADED THE GALE WATCH TO A GALE WARNING AS
CONFIDENCE IS HIGH BUT MAINTAINED THE STORM WATCH FOR NOW. THE LOW
WILL WEAKEN SOME AS IT REACHES JAMES BAY BUT THEN BECOME NEARLY
STATIONARY WHICH WILL ALLOW A FAIRLY STRONG WESTERLY GRADIENT TO
CONTINUE INTO THIS WEEKEND WITH GALES ENDING ACROSS THE NORTH
FRIDAY NIGHT OR SATURDAY MORNING. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039...3 AM THURSDAY
TO 6 PM THURSDAY.
HIGH WIND WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022...6
PM THURSDAY TO 6 AM FRIDAY.
HIGH WIND WATCH...ILZ023-ILZ032-ILZ033-ILZ039...6 PM THURSDAY TO
3 AM FRIDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...3 AM THURSDAY
TO 6 PM THURSDAY.
HIGH WIND WATCH...INZ001-INZ002...6 PM THURSDAY TO 6 AM FRIDAY.
HIGH WIND WATCH...INZ010-INZ011-INZ019...6 PM THURSDAY TO 3 AM
FRIDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM THURSDAY TO
MIDNIGHT FRIDAY.
STORM WATCH...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...3 PM
THURSDAY TO 9 PM THURSDAY.
STORM WATCH...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...9 PM
THURSDAY TO 10 AM FRIDAY.
&&
$$
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
1213 AM MST THU FEB 20 2014
.UPDATE...
ISSUED AT 806 PM MST WED FEB 19 2014
MADE SOME MINOR ADJUSTMENTS TO THE FORECAST. MAJORITY OF THE
FORECAST REMAINS UNCHANGED. WINDS ARE BEGINNING TO PICK UP WITH
LOCATIONS ACROSS NORTHEAST COLORADO NOW SUSTAINED AT 25 KTS AND
GUSTING TO 35-37 KTS. WINDS ARE EXPECTED TO CONTINUE INCREASING
THIS EVENING AS THE FRONT BLASTS THROUGH. SOME GUIDANCE CONTINUES
TO SUGGEST THAT WINDS WILL REALLY INCREASE OVER PORTIONS OF
NORTHWEST KANSAS LATE TONIGHT...POSSIBLY EXCEEDING HIGH WIND
WARNING CRITERIA. A SHORTER FUSED HIGH WIND WARNING MAY BE NEEDED
HOWEVER WITH CONFLICTING SIGNALS IN THE MODEL DATA...WAS NOT
CONFIDENT ENOUGH TO MAKE ANY CHANGES TO CURRENT HIGHLIGHTS.
WINDS FOR TOMORROW STILL LOOK ON TRACK. THERE ARE SOME INDICATIONS
THERE COULD BE SOME BLOWING DUST TOMORROW BUT WITH SNOW EXPECTED
TONIGHT AND MELTING TOMORROW...THINK THE GROUND WILL BE TOO WET IN
OUR AREA FOR BLOWING DUST PROBLEMS. THE MOST LIKELY LOCATIONS TO
SEE BLOWING DUST WOULD BE SOUTHWEST NEBRASKA WITH DUST MOVING IN
FROM THE NEBRASKA PANHANDLE. DID NOT PLACE BLOWING DUST INTO THE
GRIDS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 230 PM MST WED FEB 19 2014
LATEST RAP UPPER LEVEL ANALYSIS SHOWS TROUGH CENTERED OVER
SASKATCHEWAN CANADA WITH MEAN AXIS EXTENDING SOUTH OVER MONTANA
AND UTAH. AT THE SURFACE A COLD FRONT CURRENTLY EXTENDS FROM THE
DAKOTAS ACROSS CENTRAL WYOMING AND CENTRAL UTAH. OVER EASTERN
COLORADO A 994MB SURFACE LOW HAS DEVELOPED WITH TIGHT SOUTHERLY
GRADIENT IN PLACE OVER OUR CWA.
REGARDING WINTER WEATHER ADVISORY TONIGHT...
WINTER STORM SHOULD DEVELOPING AS TROUGH MOVES OUT OF NORTHERN
ROCKIES. UPPER LEVEL FORCING SHOULD INCREASE THIS EVENING WITH
COLD FRONT PUSHING SOUTH INTO NW PART OF THE CWA BY ABOUT
03Z...AND THEN ACROSS THE REMAINING CWA THROUGH 09Z. WHILE THERE
ISNT REALLY STRONG CAA BEHIND THIS FRONT...CHANGEOVER SHOULD BE
RELATIVELY QUICK FOR ALL BUT THE FAR SOUTHEAST AS SATURATION TO
WETBULB TEMP WOULD SUPPORT SNOW REACHING SURFACE. BEHIND THIS
FRONT THE COMBINATION OF VERY HIGH 3-6 HOUR PRESSURE RISES AND
STEEP LAPSE RATES WILL HELP MIX A VERY STRONG LLJ TO THE
SURFACE...WITH NEAR WARNING CRITERIA WINDS (60 MPH GUSTS)
POSSIBLE. GUIDANCE HAS GENERALLY TRENDED BACK A LITTLE ON WINDS
ALOFT COMPARED TO A DAY AGO...BUT CONFIDENCE IS IS STILL HIGH FOR
GUSTS AROUND 55 MPH (ISOLATED 60MPH). SHORT RANGE GUIDANCE
(RAP/HRRR) CONTINUES TO INDICATE A VERY INTENSE AND PROGRESSIVE
BAND OF PRECIP MOVING FROM THE NORTHWEST TO THE SOUTHEAST TONIGHT.
THIS GENERALLY MATCH RECENT TRENDS ON GUIDANCE (THOUGH THERE ARE
STILL MINOR DIFFERENCES ON QPF AMOUNTS AND POSITION).
TIMING/POSITION OF DEFORMATION PRECIP BAND WILL DETERMINE LOCATION
OF HIGHER SNOWFALL RATES AND TIMING OF POSSIBLE WHITEOUT
CONDITIONS. SNOW RATES WITH THIS BAND COULD BE QUITE INTENSE AS
MODEL CROSS SECTION CONTINUE TO INDICATE AN UNSTABLE LAYER
ASSOCIATED WITH THE BAND...WHICH COULD LEAD TO SNOWFALL RATES OF
AROUND 2" PER HOUR. DUE TO THE PROGRESSIVE NATURE OF THIS BAND THE
WORST VISIBILITIES ARE NOT EXPECTED TO MEET 3HR REQUIREMENT FOR
BLIZZARD WARNING...AND AMOUNTS WITH BAND SHOULD STILL BE AROUND 3"
MAX. NO CHANGE TO CURRENT WINTER WEATHER ADVISORY AT THIS
TIME...AND WILL ALLOW SUBSEQUENT SHIFT TO MONITOR FOR CHANGES IN
UPSTREAM TRENDS.
THURSDAY...LARGE SCALE SUBSIDENCE WILL SUPPORT RAPIDLY CLEARING
CONDITIONS FROM THE WEST TO THE EAST...WITH ALL PRECIP COMING TO
AN END AROUND SUNRISE. IT STILL LOOKS LIKE THERE WILL BE A BRIEF
REPRIEVE FROM THE STRONGEST WINDS THURSDAY MORNING BEFORE DAYTIME
MIXING BRINGS STRONGER WINDS BACK TO THE SURFACE. WINDS
ALOFT/MIXING HEIGHTS MIGHT SUPPORT NEAR WARNING CRITERIA BEING MET.
IT IS NOT A SLAM DUNK THAT WE WILL REACH WARNING CRITERIA
EVERYWHERE...AND CURRENT WIND ADVISORY THURSDAY COVERS WINDS TO 55
MPH (WHICH GENERALLY MATCHES CURRENT GUIDANCE). NO CHANGE TO WIND
ADVISORY WAS PLANNED WITH THIS UPDATE.
.LONG TERM...(SUNDAY THROUGH NEXT THURSDAY)
ISSUED AT 1206 AM MST THU FEB 20 2014
A LONGWAVE TROUGH WILL BE OVER THE NORTHERN PLAINS AND GREAT LAKES
WITH A SERIES OF SHORTWAVE TROUGHS MOVING THROUGH. THIS WILL
RESULT IN NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES AND
OCCASIONAL CHANCES FOR LIGHT SNOW. THESE SYSTEMS ARE ALL VERY WEAK
AND PRODUCE AN INCH OR LESS OF SNOW. HIGH TEMPERATURES WILL
GENERALLY BE IN THE 30S AND 40S WITH LOWS IN THE TEENS AND 20S. AT
THE VERY END OF THE LONG TERM PERIOD...COLDER AIR MAY BE TAPPED BY
A SOUTHERN STREAM SYSTEM WHICH COULD RESULT IN MUCH BELOW NORMAL
TEMPERATURES FOR THE END OF NEXT WEEK AND BETTER CHANCES OF SNOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1040 PM MST WED FEB 19 2014
VFR CONDITIONS FOR KGLD AND KMCK TO BEGIN THE TAF PERIOD WITH
CONDITIONS RAPIDLY DETERIORATING SOON. THE COLD FRONT IS ALREADY
MOVING INTO NORTHWEST KANSAS. NORTH WINDS BEHIND THE FRONT ARE
ALREADY GUSTING TO 40 KTS IN KAKO AND 42 KTS IN KLIC.
KGLD WILL BE GUSTING TO NEAR 42 KTS AROUND 08Z WITH SNOW. ALSO
INCLUDED BLOWING SNOW WITH VISIBILITY AT 1SM. A TEMPO GROUP WAS
INCLUDED FOR WHEN THE HEAVIEST BANDS OF SNOW ARE EXPECTED TO MOVE
ACROSS THE TERMINAL BETWEEN 08Z AND 11Z. VISIBILITY MAY BECOME
LIFR AT 1/2SM. SNOW SHOULD START TO TAPER OFF AROUND 12Z...THIS
TIME IS PUSHED BACK A LITTLE FROM THE 0Z TAFS SINCE RAP MODEL
UPDATES SHOW SNOW LINGERING OVER THE TERMINAL A LITTLE LONGER THAN
PREVIOUSLY THOUGHT. BY LATE MORNING...WIND GUSTS WILL RAMP UP
AGAIN TO NEAR 46 KTS AND THEN COME DOWN BY LATER AFTERNOON WITH
GUSTS DIMINISHING AROUND 0Z.
KMCK SHOULD GUST TO 35 KTS AROUND 07Z AS SHOWERS MOVE INTO THE
TERMINAL. NORTH WINDS WILL INCREASE AROUND 09Z WITH GUSTS NEAR 38
KTS AND LIGHT SNOW BEHIND THE FRONT. VISIBILITY SHOULD BE SIMILAR
TO KGLD WITH BLOWING SNOW SO HAVE IT REDUCED TO 1SM WITH A TEMPO
GROUP FOR LIFR VISIBILITY OF 1/2SM FROM 08Z TO 11Z. ALSO PUSHED
BACK ENDING TIME FOR SNOW TO 13Z. NORTHWEST WINDS WILL INCREASE
ONCE AGAIN IN THE EARLY AFTERNOON TO AROUND 40 KTS AND THEN WILL
DECREASE LATER IN THE AFTERNOON WITH GUSTS DIMINISHING AROUND 0Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL 6 AM MST /7 AM CST/ EARLY THIS
MORNING FOR KSZ001-002-013-014-027-041.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ THIS MORNING TO 5 PM MST
/6 PM CST/ THIS AFTERNOON FOR KSZ001>004-013>016-027>029-
041-042.
WINTER WEATHER ADVISORY UNTIL 8 AM CST THIS MORNING FOR KSZ003-
004-015-016-028-029-042.
CO...WINTER WEATHER ADVISORY UNTIL 6 AM MST EARLY THIS MORNING FOR
COZ090>092.
WIND ADVISORY FROM 9 AM THIS MORNING TO 5 PM MST THIS AFTERNOON
FOR COZ090>092.
NE...WINTER WEATHER ADVISORY UNTIL 6 AM MST /7 AM CST/ EARLY THIS
MORNING FOR NEZ079>081.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ THIS MORNING TO 5 PM MST
/6 PM CST/ THIS AFTERNOON FOR NEZ079>081.
&&
$$
UPDATE...RRH
SHORT TERM...DR
LONG TERM...024
AVIATION...ALW/RRH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1040 PM MST WED FEB 19 2014
.UPDATE...
ISSUED AT 806 PM MST WED FEB 19 2014
MADE SOME MINOR ADJUSTMENTS TO THE FORECAST. MAJORITY OF THE
FORECAST REMAINS UNCHANGED. WINDS ARE BEGINNING TO PICK UP WITH
LOCATIONS ACROSS NORTHEAST COLORADO NOW SUSTAINED AT 25 KTS AND
GUSTING TO 35-37 KTS. WINDS ARE EXPECTED TO CONTINUE INCREASING
THIS EVENING AS THE FRONT BLASTS THROUGH. SOME GUIDANCE CONTINUES
TO SUGGEST THAT WINDS WILL REALLY INCREASE OVER PORTIONS OF
NORTHWEST KANSAS LATE TONIGHT...POSSIBLY EXCEEDING HIGH WIND
WARNING CRITERIA. A SHORTER FUSED HIGH WIND WARNING MAY BE NEEDED
HOWEVER WITH CONFLICTING SIGNALS IN THE MODEL DATA...WAS NOT
CONFIDENT ENOUGH TO MAKE ANY CHANGES TO CURRENT HIGHLIGHTS.
WINDS FOR TOMORROW STILL LOOK ON TRACK. THERE ARE SOME INDICATIONS
THERE COULD BE SOME BLOWING DUST TOMORROW BUT WITH SNOW EXPECTED
TONIGHT AND MELTING TOMORROW...THINK THE GROUND WILL BE TOO WET IN
OUR AREA FOR BLOWING DUST PROBLEMS. THE MOST LIKELY LOCATIONS TO
SEE BLOWING DUST WOULD BE SOUTHWEST NEBRASKA WITH DUST MOVING IN
FROM THE NEBRASKA PANHANDLE. DID NOT PLACE BLOWING DUST INTO THE
GRIDS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 230 PM MST WED FEB 19 2014
LATEST RAP UPPER LEVEL ANALYSIS SHOWS TROUGH CENTERED OVER
SASKATCHEWAN CANADA WITH MEAN AXIS EXTENDING SOUTH OVER MONTANA
AND UTAH. AT THE SURFACE A COLD FRONT CURRENTLY EXTENDS FROM THE
DAKOTAS ACROSS CENTRAL WYOMING AND CENTRAL UTAH. OVER EASTERN
COLORADO A 994MB SURFACE LOW HAS DEVELOPED WITH TIGHT SOUTHERLY
GRADIENT IN PLACE OVER OUR CWA.
REGARDING WINTER WEATHER ADVISORY TONIGHT...
WINTER STORM SHOULD DEVELOPING AS TROUGH MOVES OUT OF NORTHERN
ROCKIES. UPPER LEVEL FORCING SHOULD INCREASE THIS EVENING WITH
COLD FRONT PUSHING SOUTH INTO NW PART OF THE CWA BY ABOUT
03Z...AND THEN ACROSS THE REMAINING CWA THROUGH 09Z. WHILE THERE
ISNT REALLY STRONG CAA BEHIND THIS FRONT...CHANGEOVER SHOULD BE
RELATIVELY QUICK FOR ALL BUT THE FAR SOUTHEAST AS SATURATION TO
WETBULB TEMP WOULD SUPPORT SNOW REACHING SURFACE. BEHIND THIS
FRONT THE COMBINATION OF VERY HIGH 3-6 HOUR PRESSURE RISES AND
STEEP LAPSE RATES WILL HELP MIX A VERY STRONG LLJ TO THE
SURFACE...WITH NEAR WARNING CRITERIA WINDS (60 MPH GUSTS)
POSSIBLE. GUIDANCE HAS GENERALLY TRENDED BACK A LITTLE ON WINDS
ALOFT COMPARED TO A DAY AGO...BUT CONFIDENCE IS IS STILL HIGH FOR
GUSTS AROUND 55 MPH (ISOLATED 60MPH). SHORT RANGE GUIDANCE
(RAP/HRRR) CONTINUES TO INDICATE A VERY INTENSE AND PROGRESSIVE
BAND OF PRECIP MOVING FROM THE NORTHWEST TO THE SOUTHEAST TONIGHT.
THIS GENERALLY MATCH RECENT TRENDS ON GUIDANCE (THOUGH THERE ARE
STILL MINOR DIFFERENCES ON QPF AMOUNTS AND POSITION).
TIMING/POSITION OF DEFORMATION PRECIP BAND WILL DETERMINE LOCATION
OF HIGHER SNOWFALL RATES AND TIMING OF POSSIBLE WHITEOUT
CONDITIONS. SNOW RATES WITH THIS BAND COULD BE QUITE INTENSE AS
MODEL CROSS SECTION CONTINUE TO INDICATE AN UNSTABLE LAYER
ASSOCIATED WITH THE BAND...WHICH COULD LEAD TO SNOWFALL RATES OF
AROUND 2" PER HOUR. DUE TO THE PROGRESSIVE NATURE OF THIS BAND THE
WORST VISIBILITIES ARE NOT EXPECTED TO MEET 3HR REQUIREMENT FOR
BLIZZARD WARNING...AND AMOUNTS WITH BAND SHOULD STILL BE AROUND 3"
MAX. NO CHANGE TO CURRENT WINTER WEATHER ADVISORY AT THIS
TIME...AND WILL ALLOW SUBSEQUENT SHIFT TO MONITOR FOR CHANGES IN
UPSTREAM TRENDS.
THURSDAY...LARGE SCALE SUBSIDENCE WILL SUPPORT RAPIDLY CLEARING
CONDITIONS FROM THE WEST TO THE EAST...WITH ALL PRECIP COMING TO
AN END AROUND SUNRISE. IT STILL LOOKS LIKE THERE WILL BE A BRIEF
REPRIEVE FROM THE STRONGEST WINDS THURSDAY MORNING BEFORE DAYTIME
MIXING BRINGS STRONGER WINDS BACK TO THE SURFACE. WINDS
ALOFT/MIXING HEIGHTS MIGHT SUPPORT NEAR WARNING CRITERIA BEING MET.
IT IS NOT A SLAM DUNK THAT WE WILL REACH WARNING CRITERIA
EVERYWHERE...AND CURRENT WIND ADVISORY THURSDAY COVERS WINDS TO 55
MPH (WHICH GENERALLY MATCHES CURRENT GUIDANCE). NO CHANGE TO WIND
ADVISORY WAS PLANNED WITH THIS UPDATE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 230 PM MST WED FEB 19 2014
THURSDAY NIGHT-SATURDAY...DRY CONDITIONS EXPECTED WITH VARYING
AMOUNTS OF CLOUDINESS...THICK AT TIMES. BREEZY TO PERHAPS WINDY
CONDITIONS FROM THE NORTHWEST LATE FRIDAY MORNING THROUGH THE
AFTERNOON. HIGHS FRIDAY UPPER 40S FAR NORTHWEST WITH 50S OVER THE
REMAINDER OF THE AREA. FOR SATURDAY COOLER BEHIND FRIDAYS FRONTAL
PASSAGE WITH UPPER 30S NORTHWEST TO MID/UPPER 40S FAR
SOUTH/SOUTHEAST. LOWS THROUGH THE PERIOD GENERALLY IN THE 20S.
SATURDAY NIGHT-WEDNESDAY NIGHT...FORECAST AREA UNDER NORTHWEST FLOW
THROUGH THE PERIOD. WILL HAVE A CHANCE OF SOME LIGHT PRECIPITATION
SATURDAY NIGHT AS A BATCH OF 850-500 MOISTURE MOVES ACROSS AREAS
GENERALLY ALONG AND NORTH OF THE INTERSTATE. SHOULD HAVE A LULL IN
ACTIVITY SUNDAY WITH A SMALL CHANCE OF PRECIP ACROSS THE NORTHEAST
SUNDAY NIGHT INTO MONDAY. COULD SEE ANOTHER ROUND OF LIGHT PRECIP
MONDAY NIGHT A BIT FURTHER WEST THEN PREVIOUS DAYS NEAR PROXIMITY
TO FAVORABLE PORTION OF UPPER JET. TUESDAY AND WEDNESDAY LOOK TO
BE DRY.
HIGH TEMPERATURES A BIT BELOW NORMAL SUNDAY THROUGH TUESDAY WITH
NEAR NORMAL READINGS WEDNESDAY. LOWS THROUGH THE PERIOD PRETTY
CLOSE TO NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1040 PM MST WED FEB 19 2014
VFR CONDITIONS FOR KGLD AND KMCK TO BEGIN THE TAF PERIOD WITH
CONDITIONS RAPIDLY DETERIORATING SOON. THE COLD FRONT IS ALREADY
MOVING INTO NORTHWEST KANSAS. NORTH WINDS BEHIND THE FRONT ARE
ALREADY GUSTING TO 40 KTS IN KAKO AND 42 KTS IN KLIC.
KGLD WILL BE GUSTING TO NEAR 42 KTS AROUND 08Z WITH SNOW. ALSO
INCLUDED BLOWING SNOW WITH VISIBILITY AT 1SM. A TEMPO GROUP WAS
INCLUDED FOR WHEN THE HEAVIEST BANDS OF SNOW ARE EXPECTED TO MOVE
ACROSS THE TERMINAL BETWEEN 08Z AND 11Z. VISIBILITY MAY BECOME
LIFR AT 1/2SM. SNOW SHOULD START TO TAPER OFF AROUND 12Z...THIS
TIME IS PUSHED BACK A LITTLE FROM THE 0Z TAFS SINCE RAP MODEL
UPDATES SHOW SNOW LINGERING OVER THE TERMINAL A LITTLE LONGER THAN
PREVIOUSLY THOUGHT. BY LATE MORNING...WIND GUSTS WILL RAMP UP
AGAIN TO NEAR 46 KTS AND THEN COME DOWN BY LATER AFTERNOON WITH
GUSTS DIMINISHING AROUND 0Z.
KMCK SHOULD GUST TO 35 KTS AROUND 07Z AS SHOWERS MOVE INTO THE
TERMINAL. NORTH WINDS WILL INCREASE AROUND 09Z WITH GUSTS NEAR 38
KTS AND LIGHT SNOW BEHIND THE FRONT. VISIBILITY SHOULD BE SIMILAR
TO KGLD WITH BLOWING SNOW SO HAVE IT REDUCED TO 1SM WITH A TEMPO
GROUP FOR LIFR VISIBILITY OF 1/2SM FROM 08Z TO 11Z. ALSO PUSHED
BACK ENDING TIME FOR SNOW TO 13Z. NORTHWEST WINDS WILL INCREASE
ONCE AGAIN IN THE EARLY AFTERNOON TO AROUND 40 KTS AND THEN WILL
DECREASE LATER IN THE AFTERNOON WITH GUSTS DIMINISHING AROUND 0Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL 6 AM MST /7 AM CST/ THURSDAY FOR
KSZ001-002-013-014-027-041.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ TO 5 PM MST /6 PM CST/
THURSDAY FOR KSZ001>004-013>016-027>029-041-042.
WINTER WEATHER ADVISORY UNTIL 8 AM CST THURSDAY FOR KSZ003-004-
015-016-028-029-042.
CO...WINTER WEATHER ADVISORY UNTIL 6 AM MST THURSDAY FOR COZ090>092.
WIND ADVISORY FROM 9 AM TO 5 PM MST THURSDAY FOR COZ090>092.
NE...WINTER WEATHER ADVISORY UNTIL 6 AM MST /7 AM CST/ THURSDAY FOR
NEZ079>081.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ TO 5 PM MST /6 PM CST/
THURSDAY FOR NEZ079>081.
&&
$$
UPDATE...RRH
SHORT TERM...DR
LONG TERM...99
AVIATION...ALW/RRH
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1229 AM EST THU FEB 20 2014
.UPDATE...
ISSUED AT 942 PM EST WED FEB 19 2014
ADJUSTED MIN TEMPS UP A COUPLE OF DEGREES...MAINLY OVER THE W AND
NEAR THE WI BORDER WHERE HI CLDS HAVE ARRIVED BEFORE SFC WINDS COULD
DECOUPLE. BUT CONCERN THAT HI CLDS MIGHT THIN LATER TNGT WITH
RELATIVELY LGT WINDS/OVERALL DRY AIRMASS IN PLACE LIMITED THE
ADJUSTMENT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 518 PM EST WED FEB 19 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW TROF MOVING ACROSS THE
ROCKIES WITH 2 MAIN SHORTWAVES OF INTEREST THAT WILL CONSPIRE TO
BRING A STRONG WINTER STORM TO THE UPPER LAKES. ONE IS OVER SRN
SASKATCHEWAN/MT AND THE OTHER IS MOVING ACROSS NV/UT. WELL OUT AHEAD
OF THESE FEATURES...A QUIET NIGHT IS EXPECTED ACROSS THE FCST AREA.
MAINLY CLEAR SKIES INITIALLY WILL GIVE WAY TO INCREASING HIGH AND
MID CLOUDS DURING THE NIGHT. LIGHT WINDS AND LACK OF SIGNIFICANT
CLOUD COVER EARLY SHOULD ALLOW TEMPS OVER THE CNTRL AND E TO FALL
QUICKLY. LEANED TOWARD SOME OF THE COLDER GUIDANCE WITH MINS IN THE
MID TEENS IN THE INTERIOR. OUT W...DEVELOPING LIGHT SOUTHERLY FLOW
AND A QUICKER INCREASE IN CLOUDS SHOULD HOLD TEMPS UP INTO THE
LOW/MID 20S.
ON THU...LOW PRES ORGANIZING OVER THE SRN PLAINS EARLY IN THE MORNING
WILL LIFT NE INTO THE MID MISSISSIPPI VALLEY DURING THE AFTN.
GENERAL MODEL TREND IN THE LAST DAY OR SO HAS BEEN FOR A SLOWER
EXPANSION OF PCPN NE INTO THE UPPER LAKES AS SYSTEM IS TENDING TO
START THE RAPID DEEPENING PHASE MORE QUICKLY BEFORE REACHING THE
UPPER LAKES. OPTED TO FOLLOW THIS TREND AND FAVOR THE SLOWER
SOLUTIONS. AS A RESULT...PCPN ONSET HAS BEEN PUSHED BACK SOME. MAIN
PUSH OF HEAVY PCPN IS NOT EXPECTED UNTIL THU NIGHT WHEN IT WILL
RAPIDLY SPREAD ACROSS THE AREA. INITIALLY...EVAPORATIVE/ADIABATIC
COOLING SHOULD LEAD TO PTYPE AS MAINLY SNOW...BUT DID INCLUDE SOME
MENTION OF MIXED PTYPES OVER ABOUT THE SE HALF.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 518 PM EST WED FEB 19 2014
MAIN CONCERN FOR THE LONG TERM FORECAST IS THE WINTER STORM EXPECTED
ON THURSDAY NIGHT AND FRIDAY.
EARLIER MODEL RUNS HAVE CONSISTENTLY KEPT THE TWO SURFACE LOWS
CROSSING FROM ILLINOIS AND MINNESOTA THURSDAY AFTERNOON TO A MERGED
LOW OVER CENTRAL UPPER MICHIGAN BY LATE THURSDAY EVENING. THIS
BRINGS WARM AIR AND HENCE MIXED PRECIPITATION INTO PORTIONS OF
CENTRAL AND EASTERN UPPER MICHIGAN. CONCERNS THIS PAST FEW DAYS HAVE
BEEN ABOUT THE FORECASTED LOW TRACK SHIFTING AS THE MODELS HAD NOT
REALLY BEEN ABLE TO ADEQUATELY SAMPLE THE SYSTEM UP UNTIL TODAY.
HOWEVER...NOW THAT THE LOW PRESSURE TROUGH RESPONSIBLE FOR THE
DEVELOPMENT OF THIS SYSTEM HAS MOVED ONSHORE IN THE PACIFIC
NORTHWEST...DIFFERENCES IN THE MODELS HAVE DEVELOPED. THE 6Z NAM
BEGAN TRENDING THE SYSTEM EASTWARD...AND THE 12Z NAM HAS COMPLETELY
MOVED THE LOW PRESSURE CENTER LATE THURSDAY EVENING FROM THE CENTRAL
U.P. TO OVER NORTHERN LAKE MICHIGAN. IT IS ALSO SLOWER THAN THE
OTHER SOLUTIONS. FURTHER COMPLICATING MATTERS...THE 12Z GEM MOVED
THE LOW PRESSURE CENTER FURTHER WEST OVER NORTH CENTRAL UPPER
MICHIGAN. THE 12Z GFS HOWEVER...HAS TRENDED SLIGHTLY WESTWARD FROM
ITS 6Z SOLUTION. THIS PUTS THE LOW OVER WESTERN UPPER MI BY 6Z
FRIDAY.
OVERALL...FURTHER EAST SOLUTIONS DIMINISH MIXED PRECIPITATION
CONCERNS AND PULL THE HEAVIEST CORE OF SNOW FURTHER EAST...WHEREAS
PREVIOUS FCST HAD IT MAINLY OVER THE WEST. FOR THIS
FORECAST...DECIDED TO LEAN TOWARDS THE WESTERN SOLUTIONS AS THIS HAS
BEEN THE MORE PERSISTENT SOLUTION. STARTED TRENDING SLIGHTLY MORE
WESTWARD WITH THE FORECAST GRIDS AS A RESULT...NAMELY THE
GFS/GEM/ECMWF COMPROMISE. AS FAR AS TIMING GOES...THE GEM BRINGS
THINGS IN SLOWER. THE 00Z ECMWF/12Z GFS BRING THE LOW THROUGH
QUICKER BY ABOUT 6 HRS...WITH THE CENTER OVER NORTH CENTRAL UPPER MI
BY 6Z FRIDAY. THE GEM IS STILL OVER CENTRAL WI AT THIS TIME.
PREVIOUS RUNS OF THE GEM HAD TIMING MORE LIKE THAT OF THE RECENT
RUNS OF THE ECMWF/GFS...THOUGH THE GFS TENDS TO BE MORE PROGRESSIVE
WITH SYSTEMS. WILL GO MIDDLE OF THE ROAD FOR NOW TO COMPENSATE FOR
THIS.
THE GFS/GEM/ECMWF BLEND SHOWS A BROAD AREA OF ISENTROPIC ASCENT
OVERSPREADING THE AREA STARTING THURSDAY AFTERNOON...WITH THE
STRONGEST MOISTURE TRANSPORT FROM THE 18Z THUR-06Z FRI TIME FRAME
OVER LOWER MICHIGAN...NORTHERN WI...AND CENTRAL/EASTERN UPPER
MICHIGAN. 700/850MB FGEN BAND MOVES FROM ROUGHLY SOUTH TO NORTH
ACROSS THE AREA BEGINNING AROUND THIS TIME AND CONTINUING THROUGH AS
SYSTEM DEEPENS WITH NEGATIVELY TILTING UPPER TROUGH. THE SYSTEM
BEGINS TO OCCLUDE...AND THE TROWAL DEVELOPS AND POSITIONS ITSELF/AND
THE ASSOCIATED FGEN BAND OVER WESTERN UPPER MI.
AS FAR AS PTYPE GOES...THERE ARE DIFFERENCES BETWEEN THE 12Z GFS/12Z
GEM/00Z ECMWF WITH REGARDS TO THE HEIGHT/TEMP OF THE WARMEST LAYER
ALOFT AND DEPTH OF THE SURFACE COLD LAYER FROM 00-03Z FRI...AND THE
SURFACE WARM LAYER AROUND 6-9Z FRI. BY 12Z FRIDAY THE MODELS ARE
CONSISTENT IN HAVING THE WHOLE SOUNDING BELOW ZERO.
IT LOOKS LIKE THE EASTERN HALF WILL SEE THE BEST SHOT FOR FREEZING
RAIN FROM 00-9Z...AND THE RAIN/SNOW LINE SEEMS TO SET UP FROM
EASTERN MARQUETTE COUNTY TO EASTERN DICKINSON COUNTY. ONCE WE GET
PAST 9Z...THE ENTIRE PROFILE IN THIS AREA DROPS BELOW ZERO.
GENERALLY...MIXED PRECIP TIME LOOKS TO BE QUICK ESPECIALLY GIVEN THE
STRONG DYNAMICS IN THE SYSTEM. MAX TS ALOFT REACH A MAX OF 2C WITH
THE WARM GFS...AND STAY BELOW ZERO WITH THE 00Z ECMWF. EAST OF THIS
LINE...WARM LAYER REACHES 3C AROUND 850 AND THE COLD SURFACE LAYER
IS FAIRLY SHALLOW AND EVEN SNEAKS ABOVE ZERO FROM 6-9Z ACCORDING TO
THE GEM...BRINGING A POT POURRI OF PRECIPITATION. THIS AREA IS STILL
ON TRACK FOR SEEING MORE ICE ACCUMULATION. ALL OTHER AREAS WILL BE
PRIMARILY SNOW.
WINDS ARE A CONSIDERABLE ISSUE WITH THIS SYSTEM AS WELL. STRONG
PRESSURE RISE FALL COUPLET SNEAKS IN WITH THE SYSTEM...BRINGING A
SIGNIFICANT ISALLOBARIC COMPONENT TO THE WIND. THIS IS ESPECIALLY
THE CASE ACROSS EASTERN UPPER MICHIGAN EARLY THURSDAY EVENING UNTIL
AROUND 06Z...AND THEN IN THE WEST AND NORTH CENTRAL BY FRIDAY
MORNING/AFTERNOON. THIS WILL ONLY ADD TO THE REDUCED VISIBILITY WITH
EXTENSIVE BLOWING/DRIFTING SNOW. GUSTS IN SOME OF THESE
AREAS...PARTICULARLY THE EXPOSED REGIONS IN THE WEST-NORTHWEST
FAVORED REGIONS...WILL LIKELY SEE GUSTS INTO THE 40S FRIDAY.
GIVEN THE RECENT MODEL RUNS...FELT CONFIDENT ENOUGH TO GO WITH A
WINTER STORM WARNING FOR LOCATIONS WEST OF MARQUETTE/DICKINSON
COUNTIES. SNOW ACCUMULATIONS RANGE FROM ABOUT 8 TO 12 INCHES IN
THESE COUNTIES. ALSO UPGRADED THE BLIZZARD WATCH TO A WARNING FOR
KEWEENAW/N.HOUGHTON COUNTIES GIVEN THE EXTENSIVE WINDS AND SNOW.
OTHERWISE...KEPT THE REST OF THE CWA UNDER A WINTER STORM WATCH TO
PIN DOWN THE DETAILS. IF THE SYSTEM DOES SNEAK EASTWARD...WE MAY
NEED TO ADD ADDITIONAL COUNTIES INTO THE WARNING. MOST OF THE
UNCERTAINTIES WILL IMPACT THE CENTRAL/EASTERN COUNTIES THE MOST...SO
A WATCH SEEMED BEST RIGHT NOW.
FOR THE EXTENDED...WITH THE LINGERING UPPER LEVEL TROUGH IN THE
AREA...EXPECT COLDER TEMPERATURES TO RETURN. 850MB TEMPS WILL DROP
TOWARDS -25C TO -30C AS WE HEAD FURTHER INTO THE LATER TIME PERIODS.
SNOW WILL GRADUALLY CONFINE TO THE WEST WIND FAVORED REGIONS NEAR
LAKE SUPERIOR...AS ICE WILL LIKELY BE BROKEN ENOUGH TO INDUCE
INSTABILITY FOR LES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1229 AM EST THU FEB 20 2014
EXPECT VFR CONDITIONS TO PREVAIL THRU THIS MRNG AS LLVL AIRMASS IS
TOO DRY FOR FOG UNDER A VEIL OF MID/HI CLDS. AS DEEPENING LO PRES
APRCHS UPR MI FM THE S LATER TODAY...EXPECT DETERIORATING CONDITIONS
WITH GUSTY WINDS/SOME LGT SN AND BLSN/MVFR CONDITIONS ARRIVING IN
THE AFTN. CONDITIONS WL FALL TO LIFR/VLIFR FOR AT LEAST SEVERAL HRS
THIS EVNG...MAINLY AT IWD AND CMX WHERE THE PCPN WL BE IN THE FORM
OF HEAVY SN. AN EXTENDED PERIOD OF VLIFR CONDITIONS IS LIKELY AT THE
MORE EXPOSED KCMX SITE BEGINNING TNGT AND LASTING THRU MUCH OF FRI
AS THE MORE EXPOSED KEWEENAW PENINSULA WL BE PLAGUED BY SN/BLSN WITH
VERY STRONG E WINDS SHIFTING TO THE W ONCE THE SFC LO MOVES TO THE N
OF THE AREA LATE TNGT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 518 PM EST WED FEB 19 2014
WINDS WILL DIMINISH THIS EVENING...BECOMING LIGHT UNDER 15KT. WINDS
WILL THEN BEGIN TO INCREASE OVERNIGHT AHEAD OF A WINTER STORM
ORGANIZING OVER THE SOUTHERN PLAINS. E TO NE WINDS MAY REACH UPWARDS
OF 30KT OVER FAR WRN LAKE SUPERIOR BY MORNING. WINDS WILL STEADILY
INCREASE ACROSS THE LAKE THU AS THE ORGANIZING LOW PRES SYSTEM LIFTS
INTO THE MID MISSISSIPPI VALLEY. THE LOW WILL THEN RAPIDLY DEEPEN...
BECOMING AN INTENSE LOW WITH PRES BOTTOMING OUT AROUND 28.7 INCHES
AS IT MOVES NNE ACROSS CNTRL UPPER MI AND CNTRL LAKE SUPERIOR LATE
THU NIGHT AND FRI MORNING. AHEAD OF THE LOW...EASTERLY GALES WILL
DEVELOP OVER CNTRL AND ERN LAKE SUPERIOR THU EVENING. WHILE E TO NE
GALES MAY ALSO DEVELOP OVER WRN LAKE SUPERIOR...W GALES ARE MORE
LIKELY IN THE WAKE OF THE LOW FRI/FRI NIGHT. GALES WILL CONTINUE
OVER CNTRL AND ERN LAKE SUPERIOR FRI THRU SAT WITH THE POTENTIAL FOR
STORM FORCE WINDS OVER ERN LAKE SUPERIOR FRI. ALTHOUGH GALES WILL
END BY SUN...WINDS WILL LIKELY REMAIN IN THE 20-30KT RANGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING FROM 4 PM EST /3 PM CST/ THIS AFTERNOON TO
NOON EST /11 AM CST/ FRIDAY FOR MIZ002-004-009-010-084.
WINTER STORM WATCH FROM THIS AFTERNOON THROUGH FRIDAY MORNING
FOR MIZ006-007-012>014-085.
BLIZZARD WARNING FROM 7 PM THIS EVENING TO 10 PM EST FRIDAY FOR
MIZ001-003.
WINTER STORM WATCH FROM THIS AFTERNOON THROUGH FRIDAY MORNING
FOR MIZ005-011.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM THIS EVENING TO 6 PM EST SATURDAY FOR
LSZ244-245-264>267.
GALE WARNING FROM 7 AM EST /6 AM CST/ FRIDAY TO 7 AM EST /6 AM
CST/ SATURDAY FOR LSZ162-241>243-263.
LAKE MICHIGAN...
GALE WARNING FROM 7 PM THIS EVENING TO 5 PM EST FRIDAY FOR
LMZ221-248-250.
&&
$$
UPDATE...KC
SHORT TERM...ROLFSON
LONG TERM...MCD
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1156 PM CST Wed Feb 19 2014
.UPDATE:
Issued at 836 PM CST Wed Feb 19 2014
Having serious concerns that PoPs tonight are too high across
much of the area. Latest short range guidance keeps the vast
majority of the precip west and northwest of the STL Metro area
through the night. Not to say there couldn`t be some isolated to
scattered showers/t-storms just about anywhere after 06Z, but it
may not be worth the likely to categorical PoPs currently in the
forecast. The RAP focuses the low level jet over northeast MO into
central IL. This pushes the baroclinic zone north and while the
low level jet continues to be relatively strong across the entire
area, temperature/moisture advection becomes almost neutral for
the majority of the area. Will keep likely-categorical PoPs over
northern sections tonight near the baroclinic zone and the nose of
the low level jet. Further south, will start with just low
chance/slight chance and trend slowly upward through the night as
the shortwave approaches.
Carney
&&
.SHORT TERM: (Through Late Tonight)
Issued at 253 PM CST Wed Feb 19 2014
Main concerns tonight are the potential for localized flooding and
that a few thunderstorms could produce some hail near severe
limits. Showers and scattered thunderstorms have already begun to
develop over southeast Kansas this afternoon in a band of strong
moisture convergence that extends from the Central Plains into the
Mid South. The RAP shows this moisture convergence moving into
central Missouri by 00Z, which will then spreads northeast across the
CWA during the evening. Large scale ascent will increase across the
CWA tonight with the approach of the upper trough. At the same
time, the instability will also increase through the night as lapse
rates steepens with the approach of the upper trough in a highly
sheared environment. Overall coverage with any severe storms
capable of producing quarter size hail between 06-12Z is expected to
be limited in coverage over parts of central, northeast and east
central Missouri as well as adjacent sections of Illinois. A flood
watch will go into effect at midnight tonight where we expect
thunderstorms to move over the remaining snowpack. The ground is
frozen in these areas and streams and area rivers have had problems
with ice jams that could cause some localized flooding. The NMM and
NSSL WRF/GFS simulated reflectivity are similar to going forecast
which already have high chances for showers and thunderstorms this
evening across central and northeast Missouri and west central
Illinois, that then spreads southeast across the rest of the CWA
overnight.
Britt
.LONG TERM: (Thursday through Next Wednesday)
Issued at 253 PM CST Wed Feb 19 2014
Deepening surface low to lift northeast into southeastern Iowa by
18z Thursday, then into Great Lakes region by 06z Friday. In the
meantime, associated cold front to rapidly slide east through
forecast area with another round of showers and thunderstorms on
Thursday. Some of the storms could be strong with isolated severe
storms not out of the question but best chances will be east and
southeast of forecast area. Heaviest rains continue to be in an
axis from central through northeast MO and into west central IL.
Flood watch for portions of central/northeast MO and west central IL,
where there is still snow cover, to remain in effect until 00z
Friday. As for temperatures, will warm up into the mid 40s to
upper 60s by midday, then temperatures to fall through the
afternoon hours as cold front exits region. Another issue to deal
with will be the winds. Winds to pickup from the south ahead of
cold front then veer to the west and increase even more, between
15 and 25 mph with gusts near 35-40 mph at times. At this time no
wind advisory needed, but will need to keep an eye out on future
model runs to see if one will be needed.
Precipitation to move out of forecast area by 00z Friday with winds
gradually diminishing and skies clearing out. Lows will be near
normal in the mid 20s to low 30s.
On Friday, weak surface ridge to build in with winds becoming
southwesterly once again ahead of a weak cold front. Highs will
range from the upper 40s northeast to the upper 50s southwest.
As front slides through late Friday afternoon and Friday night,
energy to remain just north and northeast of forecast area, so
should see dry conditions. Did keep silent slight chance pops over
northeast MO and west central IL on Friday where some light
snow/light rain may be possible, but confidence is low right now.
By Saturday, surface ridge to build back in with cooler conditions
expected. Highs will only be in the upper 30s to mid 50s, but still
near normal for this time of year.
Beyond that, another weak shortwave to approach region Saturday
night, but confidence is low on any precipitation. So kept silent
slight chance pops for portions of forecast area for now. Lows
Saturday night will range from near 20 far north to the low 30s
far south. Dry and colder weather expected Sunday and Sunday night
with highs in the low 30s to mid 40s and lows in the upper teens
to mid 20s.
Next chance for precipitation will be Monday and Monday night,
though best chances will be over northern MO and northern half of
IL, so adjusted pops accordingly. With colder air moving in, the
precipitation will be in the form of light snow with this system.
Colder weather to persist through mid week with highs in the mid 20s
to low 40s each day and lows in the teens to low 20s.
Byrd
&&
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1138 PM CST Wed Feb 19 2014
Specifics for KUIN: The two primary issues for this TAF period
are convective trends and wind trends. Thunderstorms were moving
through KUIN at TAF issuance and should persist for a few more
hours. Additional precipitation is expected ahead of a cold
front during the mid-morning hours, but the timing and placement
of storms remains somewhat uncertain. Wind speeds and gusts will
increase markedly after 18z with gusts exceeding 40 kts.
Specifics for KCOU: The two primary issues for this TAF period are
convective trends and wind trends. Showers with embedded
thunderstorms have developed farther north and east than
previously anticipated. I cannot rule out additional precipitation
overnight given upstream radar trends, but TSRA chances appear
higher after 12z ahead of an approaching cold front. Wind speeds
and gusts will increase markedly after 16-18z. Gusts may approach
40 kts at times.
Specifics for KSTL, KSUS, KCPS: The three primary issues for this
TAF period are convective trends, wind trends, and LLWS. Light
showers were ongoing at TAF issuance invof metro area TAF sites
near a lifting warm front, but this precipitation should only last
a couple of hours at most. A separate line of thunderstorms is
expected to develop ahead of a cold front during the morning or
early afternoon hours, but the timing and placement of the storms
remains somewhat uncertain. Wind speeds and gusts will increase
markedly after 18z. Gusts may exceed 40 kts. A strong southerly
LLJ will produce LLWS conditions through the early morning.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FLOOD WATCH through Thursday afternoon FOR Audrain MO-Boone MO-
Knox MO-Lewis MO-Marion MO-Monroe MO-Pike MO-Ralls MO-
Shelby MO.
IL...FLOOD WATCH through Thursday afternoon FOR Adams IL-Brown IL-
Greene IL-Macoupin IL-Montgomery IL-Pike IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
418 AM EST THU FEB 20 2014
.SYNOPSIS...
WARM FRONT LIFTS NORTH TODAY. STRONG COLD FRONT TONIGHT. ANOTHER
SYSTEM MOVES THROUGH ON SUNDAY. SNOW MONDAY NIGHT INTO TUESDAY.
WINTER CONTINUES IN NEW WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WARM FRONT LIFTS NORTH THIS MORNING WITH BETTER CHANCES FOR RAIN
SHOWERS ACROSS SOUTHEAST OH...NORTHEAST KY...AND PORTIONS OF WV
ALONG THE OH RIVER. INCREASED POPS LIFTING WITH THE WARM FRONT TO
LIKELY...DIMINISHING AS SHOWERS MOVE NORTH.
MODELS INDICATE WIND FLOW WILL INCREASE FROM THE SOUTHWEST TO
60-70 KNOTS AT H85 AHEAD OF A COLD FRONT EXPECTED TO PASS TONIGHT.
SOME OF THESE STRONG WINDS WILL MOST LIKELY BE FELT OVER THE
HIGHER TERRAIN...AND ALONG SHOWERS WHICH WILL BE CAPABLE TO MIX
DOWN THESE WINDS. HOWEVER...IN THE WARM SECTOR IT WILL STRUGGLE
TO MIX DOWN PER UP GLIDING ASPECT EVIDENT IN ISENTROPIC SURFACES.
THE FRONT SHOULD PRODUCE A QUICK 0.5 INCHES OF RAIN...PERHAPS MORE
ALONG THE STRONGER STORM OR SHOWER.
HOLD OFF ON ISSUING A WIND ADVISORY AS THE EVENT LOOKS MARGINAL
ATTM. THE BEST WINDS 40 TO 50 KNOTS...OCCUR IN THE WARM SECTOR AS
EXPLAINED BEFORE. A WIND ADVISORY COULD BE NECESSARY ALONG OR
BEHIND THE FRONT. OR THE EVENT COULD BE TREATED WITH SPS AND
SEVERE STORM WARNINGS IF NEEDED. WILL LET DAY SHIFT TO DECIDE HOW
TO HANDLE THIS EVENT.
THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS TONIGHT WITH
DAMAGING WINDS BEING THE MAIN THREAT. SMALL HAIL CAN NOT BE RULED
OUT OF THE QUESTIONS AS FREEZING LEVELS WILL BE AROUND 9-10 KFT.
SNOW MELT HAVE CAUSE WATERS IN SMALL STREAMS TO RISE. FLOODING WAS
KEPT IN THE HAZARDOUS WEATHER OUTLOOK.
MINOR TWEAKS TO PREVIOUS TEMPERATURES. BLENDED THE RUC13 WITH MOST
GUIDANCE FOR TEMPERATURES THROUGH THE PERIOD.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
STRONG SYSTEM EXITING THE AREA AT THE OUTSET OF THE SHORT-TERM
PERIOD 12Z FRI. CONSENSUS OF NWP OUTPUT SLOWING THE FRONT JUST A BIT
OVERNIGHT FROM PREV RUNS...WITH THE VARIOUS MODELS HAVING THE SFC FRONT
LOCATED PRETTY MUCH ON OUR EASTERN CWA BORDER OF POCAHONTAS AND
RANDOLPH COUNTIES AT 12Z FRI. ELEVATED FRONT OF COURSE THEN IS A BIT
SLOWER AS WELL AND CROSSES THE HIGH PEAKS BTWN 12Z-15Z FRI MORNING
WITH A RAPID COOL DOWN FOR LOCATIONS SUCH AS SNO FROM THE LOW 40S AT
12Z FRI TO THE UPPER 20S/LOW 30S BY 15Z FRI. REFLECTED THIS IN THE
HOURLY TEMP TRACE FRIDAY MORNING. ALSO SLOWED DOWN PRECIP EXIT JUST
A BIT WITH IT...WITH LATEST NAM12 AND GFS BUFKIT SOUNDINGS STILL
INDICATING NEARLY COMPLETE SATURATION UP TO 600-500MB AT 15Z FRI.
THIS PRECIP WILL BE ALL RAIN INITIALLY ON THE HIGHEST PEAKS BUT WILL
QUICKLY CHANGE TO SNOW FOR A BRIEF WINDOW OF 1-3 HOURS AS THE PRECIP
MOVES OUT OF THE AREA. MAY GET A QUICK HALF-INCH TO PERHAPS AN INCH
OF SNOW FRI MID-MORNING AS THIS SYSTEM WINDS DOWN...BUT AGAIN THIS
SHOULD BE CONFINED TO ELEVATIONS MAINLY ABOVE 3KFT.
ONCE THE LAST OF THE PRECIP MOVES OUT...THE REMAINDER OF FRIDAY WILL
SEE IMPROVING CONDITIONS WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES BY
THE AFTERNOON HOURS WITH TEMPS INTO THE UPPER 40S TO LOWER 50S FOR
THE LOWLANDS. MAY SEE A BIT MORE STRATO-CU HANGING ON ACROSS THE
NORTHERN ZONES DURING THE AFTERNOON HOURS WITH A BIT MORE LLVL
MOISTURE TO WORK WITH. IT WILL CONTINUE TO BE A VERY WINDY DAY
ACROSS THE AREA WITH STRONG SFC LOW PRESSURE LOCATED OVER THE
NORTHERN GREAT LAKES. FOR THE LOWLANDS...EXPECT GENERAL 20G30KTS FOR
MUCH OF THE DAY...WHILE THE HIGHEST PEAKS OF THE EASTERN MOUNTAINS
SEE POTENTIALLY 40-45KT GUSTS. A 50KT GUST WOULD NOT BE IMPOSSIBLE
TO REALIZE AT THE HIGHEST ELEVATIONS...PARTICULARLY FOR AN HOUR OR
SO IMMEDIATELY FOLLOWING THE FRONTAL PASSAGE.
FRIDAY EVENING THE SFC LOW OVER THE GREAT LAKES CONTINUES TO SLOWLY
PULL AWAY WITH SFC HIGH PRESSURE LOCATED NEAR THE SMOKY MOUNTAIN
REGION BY 12Z SAT. DRY WEATHER WILL CONTINUE AND THE WORST OF THE
WINDY CONDITIONS WILL QUICKLY DISSIPATE NEAR AND AFTER SUNSET WITH
THE LOSS OF ANY MIXING. WITH A DECENT PRESSURE GRADIENT OVER THE
AREA WILL STILL MAINTAIN A PUFF OF WIND IT APPEARS. ALSO WILL SEE
SOME WARM ADVECTION MAKING INTO THE AREA BY AND AFTER 06Z SAT.
INHERITED MIN TEMPS FROM PREV SHIFT GENERALLY LOOK GOOD...WITH MINOR
ADJUSTMENTS.
SATURDAY WILL BE ANOTHER PLEASANT DAY. SFC HIGH PRESSURE SLOWLY
PULLS EAST WITH A RETURN S/SW FLOW SETTING UP BY THE AFTERNOON.
BUMPED UP MAX TEMPS FOR SATURDAY A GOOD 3-5 DEGREES AREA-WIDE WITH
925MB TEMPS PROGGED AROUND 8-9C...EXPECT TEMPS TO REBOUND INTO THE
MID 50S NORTHERN LOWLANDS AND UPPER 50S TO 60 CENTRAL AND SOUTHERN
LOWLANDS. IT WILL STILL BE ON THE BREEZY SIDE BUT NOT NEARLY AS
GUSTY AS FRIDAY...SO IT WILL PROBABLY FEEL MUCH NICER THAN FRIDAY.
SATURDAY NIGHT...INHERITED MINS THE LOW/MID 30S LOWLANDS STILL
APPEAR ON TRACK AGAIN...WITH JUST A FEW ADJUSTMENTS. A WEAK
DISTURBANCE IN THE NEAR ZONAL FLOW MAY DRAG A WEAK COLD FRONT INTO
THE NORTHERN ZONES BY END OF PERIOD AND THUS WILL CONTINUE THE
SLIGHT TO LOW CHANCE POPS FROM PREV SHIFT IN THESE AREAS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
MODELS SHOWING A WEAK SYSTEM SYSTEM MOVING THROUGH SATURDAY NIGHT
INTO SUNDAY. TYPE OF PRECIPITATION IS QUESTIONABLE BASED ON TIMING
AND HOW MUCH RADIATION OCCURS SATURDAY NIGHT IN ADVANCE OF THE
SYSTEM. USED A BLEND OF THE ECMWF AND GFS.
FOR MONDAY THROUGH WEDNESDAY...USED A BLEND OF THE GEFS ENSEMBLE
MEAN AND ECMWF ENSEMBLE MEAN. THIS KEEPS A TROUGH OVER THE EASTERN
UNITED STATES CREATING A WINTER WEATHER SITUATION WHERE VARIOUS
WAVES COULD CREATE SNOW AT TIMES. THE TIMING OF THE WAVES AND
INTENSITY OF THE COLD AIR REMAIN IN QUESTION HOWEVER...AS VARIOUS
ENSEMBLE MEMBERS VARY CONSIDERABLY.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
WIND BECOME CALM OVERNIGHT AS THE ATMOSPHERE DECOUPLES. WEAK HIGH
PRESSURE KEEPS CONDITIONS DRY TONIGHT INTO EARLY THURSDAY.
SFC WIND BECOMES SOUTHEAST AND THEN SOUTH THURSDAY INTO THURSDAY
NIGHT. ALOFT...DEEP SOUTHWESTERLY FLOW INCREASES AFTER 12Z
THURSDAY AHEAD OF A STRONG COLD FRONT. MODELS SHOW H85 WINDS
INCREASING TO 50 BY 18Z THURSDAY...AND EVEN 70 KNOTS BY 06Z
FRIDAY...AHEAD OF THE FRONT.
MAIN SQUALL LINE WITH FAST MOVING SHOWERS/EMBEDDED THUNDERSTORM
SHOULD STILL BE WEST OF AREA AT 00Z FRIDAY. CONVECTION AHEAD OF
FROPA SHOULD REACH SOUTHEAST OH BY 06-09Z FRIDAY. THERE IS A
SLIGHT RISK FOR DAMAGING WINDS WITH STORMS WITH THIS FROPA. THE
WINDY SHOWERS OR STORMS WILL SPREAD QUICKLY EAST. THIS WILL BE AN
HIGH SHEAR...LOW CAPE ENVIRONMENT...WITH PW AROUND 1 INCH.
LOW LEVEL WIND SHEAR IS POSSIBLE EARLY THURSDAY MORNING AS WINDS
ALOFT INCREASE AND THE SFC REMAINS DECOUPLED FOR FEW HOURS UNTIL
DIURNAL MIXING TAKES PLACE. WILL CONSIDER TO CODE LLWS IN 12Z TAF
ISSUANCE.
HAVE CLOUDS THICKENING FROM 12 TO 18Z THURSDAY FROM SOUTH TO NORTH
DOWN TO 3500 FEET...EXCEPT 2500 FEET EXTREME NORTHWEST PORTIONS OF
OUR CWA. CEILINGS DETERIORATE WITH THE PROXIMITY OF FROPA
OVERNIGHT THURSDAY NIGHT DOWN TO AROUND 2000 FEET UNDER RAIN
SHOWERS. BRIEF PERIODS OF IFR POSSIBLE ALONG HEAVIEST SHOWERS.
CEILINGS WILL REMAIN AT LEAST MVFR FOR THE MOST PART AFTER FROPA
EXCEPT IFR ALONG THE EASTERN MOUNTAINS BY FRIDAY 12Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MORE SHOWER COVERAGE ASSOCIATED WITH THE WARM
FRONT A BIT FURTHER EAST THAN FORECAST. TIMING COVERAGE OF LOWER
CLOUDS DEVELOPING ON EASTERN SLOPES 18Z THURSDAY TO 00Z FRIDAY
COULD VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE THU 02/20/14
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EST 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H M M H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY L L L H H H H H M M M H
CKB CONSISTENCY L H H H H H H H H H H H
AFTER 06Z FRIDAY...
IFR POSSIBLE THURSDAY NIGHT IN FAST MOVING AND GUSTY SHOWERS...AND
POSSIBLY A BRIEF THUNDERSTORM.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/50
NEAR TERM...ARJ
SHORT TERM...50
LONG TERM...RPY
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
456 AM EST THU FEB 20 2014
.SYNOPSIS...
HIGH PRESSURE OVER CENTRAL PENNSYLVANIA EARLY THIS MORNING WILL
SLIDE EAST AND MOVE OFF THE MID-ATLANTIC COAST BY THIS AFTERNOON.
A WARM FRONT WILL LIFT NORTH ACROSS THE AREA EARLY TONIGHT...BEFORE
A STRONG COLD FRONT RACES EAST ACROSS THE COMMONWEALTH EARLY FRIDAY.
TEMPERATURES SHOULD AVERAGE NEAR OR SLIGHTLY ABOVE NORMAL INTO
WEEKEND BEFORE TRENDING COLDER INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY AM MODIS 11-3.7UM IMAGERY SHOWING EXTENSIVE VALLEY FOG AND
STRATUS ACROSS NORTHWEST PA...THE RESULT OF CLEAR SKIES AND CALM
WIND UNDER HIGH PRES SYSTEM. LAMP AND RAP DATA BOTH INDICATE AREAS
OF FOG WILL LIFT BTWN 12Z-14Z. FOCUS WILL THEN BE ON BAND OF SHRA
LIFTING NORTHEAST FROM THE OHIO VALLEY ALONG APPROACHING WARM
FRONT. REGIONAL RADAR MOSAIC ALREADY SHOWING THIS DEVELOPING BAND
OF RAIN ACROSS ILLINOIS/INDIANA...WHERE NOSE OF LL JET INTERSECTS
RETREATING 8H BAROCLINIC ZONE. ALL NEAR TERM MDL DATA TIMES THIS
FEATURE THRU CENTRAL PA BTWN 17Z-23Z. ENSEMBLE MFLUX VALUES AND
QPF PROBS SUPPORT NEAR 100 PCT CHC OF RAIN ACROSS THE NW
MTNS...WITH PROGRESSIVELY LOWER CHC OF SHOWERS FURTHER SE.
EARLY SUNSHINE WILL FADE BEHIND LOWERING/THICKENING CLOUD COVER
TODAY. HOWEVER...A RELATIVELY MILD START TO THE DAY...COMBINED
WITH DEVELOPING SOUTHERLY FLOW WEST OF RETREATING HIGH PRES SHOULD
PUSH READINGS INTO THE 40S BY AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
A STRONG MID-LVL TROUGH ENTERING THE PLAINS STATES THIS AM IS
FCST TO TAKE ON A NEGATIVE TILT AS IT REACHES THE UPPER GRT LKS
AND MS/OH VLYS TNGT. THE MAIN SYNOPTIC FEATURE OF INTEREST WILL
BE THE SHARP/TRAILING COLD FRONT WHICH WILL BE CROSSING THE
APPLCHNS AROUND 12Z FRI. THIS FRONT IS EXPECTED TO BE A FOCUS FOR
A THIN LINE OF LOW-TOPPED CONVECTION WHICH COULD REACH THE WRN
ALLEGHENIES EARLY FRI MORNING.
SPC CONVECTIVE OUTLOOKS PLACE THE AREA IN GENERAL RISK...AND
MENTIONED THIS POTENTIAL FOR LOW TOPPED SQUALL LINE WITH ELEVATED
INSTABILITY IN HWO ALONG WITH POTENTIAL FOR GUSTY WINDS /AS VERY
POTENT LLJET DEVELOPS/. THE SYSTEM IS PROGRESSIVE WHICH WILL LIMIT
HVY RAIN POTNL/FLOOD THREAT...HOWEVER ICE JAM EFFECTS COULD BE A
CONCERN. ATTM DO NOT ANTICIPATE RAPID SNOW-MELT.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS COLD FRONT SLIDES ACROSS ON FRI...PRECIP WILL PUSH EASTWARD
AND COOLER AIR WILL FILTER BACK INTO THE REGION. GFS/ECMWF NOW IN
QUITE GOOD ALIGNMENT WITH MAIN FEATURES AS THIS SYSTEM
EVOLVES...WITH PRECIP ENDING BY LUNCHTIME FRI.
AFTER THAT...BROAD TROUGH BECOMES MORE AND MORE ENTRENCHED ACROSS
EASTERN 2/3RDS OF U.S. THROUGH NEXT MIDWEEK...GIVING US A SLOW
AND STEADY RETURN BACK TO BELOW NORMAL TEMPERATURES. FOR THE
UPCOMING WEEKEND...WEAK FRONT PUSHES THROUGH THAT MAY BRING LIGHT
ACCUMS OF SNOW. OTHERWISE...NO BIG SYSTEMS THROUGH TUE AS
PERSISTENT NW FLOW CONTINUES WHILE HUDSON BAY LOW GRADUALLY
DEEPENS AND PUSHES COLDER AIR FURTHER SOUTHWARD. SNOWFLAKES WILL
LINGER OVER THE WESTERN/NORTHERN HIGHER TERRAIN.
NOTABLE WAVE PROGGED TO SWING AROUND THE TROUGH NEXT MIDWEEK...AND
LONG RANGE MODELS /BOTH ECMWF AND GFS/ BEGINNING TO HINT AT
POTENTIAL LOW DEVELOPMENT AS IT SLIDES OFF THE EAST COAST. BUT THAT
REMAINS A LONG WAY OFF FOR NOW.
AS FAR AS THE SNOW COVER AND RIVER ICE...WARMING TREND LATE THIS
WEEK WILL BE FAIRLY SHORT-LIVED...SO MELTING OF SNOW AND ICE WILL
REMAIN GRADUAL...WHICH SHOULD KEEP POTENTIAL FOR WIDESPREAD
PROBLEMS LOW.
&&
.AVIATION /10Z THURSDAY THROUGH MONDAY/...
EARLY AM SATL IMAGERY SHOWS VALLEY FOG HAS FORMED ACROSS THE NW
MTNS. ANOTHER COUPLE HOURS OF RADIATIONAL COOLING SHOULD ENSURE
THAT LOW CLOUDS/FOG PERSIST AT KBFD THRU THE NEXT FEW HOURS.
ELSEWHERE...CONDITIONAL CLIMATOLOGY BASED ON 09Z SFC OBS SUGGEST
THERE IS ARND A 40 PCT CHC OF KUNV AND KAOO BRIEFING DIPPING TO
IFR ARND 12Z.
AS HIGH PRES PASSES EAST OF THE AREA...EXPECT A DEVELOPING
SOUTHERLY BREEZE TO CAUSE ANY FOG TO LIFT BTWN 12Z-14Z. LATEST
LAMP/RAP OUTPUT BOTH SUPPORT THIS SCENARIO WITH A RETURN TO
WIDESPREAD VFR CONDS OVER MOST OF CENTRAL PA FOR MOST OF THE
DAYLIGHT HOURS. A BAND OF SHRA ASSOC WITH A WARM FRONT WILL LIKELY
LIFT THRU THE AREA DURING THE AFTN...AFFECTING MAINLY NW PA WHERE
MVFR REDUCTIONS ARE LIKELY AT KBFD.
A STRONG CORE OF SOUTHERLY WINDS ALOFT WILL OVERSPREAD THE REGION
THIS EVENING IN ADVANCE OF AN APPROACHING COLD FRONT. THIS WILL
LIKELY LEAD TO LLWS CRITERIA...ESP ACROSS THE W MTNS. MDL
SOUNDINGS ALSO SUPPORT THE IDEA OF WIDESPREAD MVFR /POSS IFR/ CIGS
DEVELOPING THIS EVENING IN RESPONSE TO A SURGE OF MOISTURE WORKING
INTO THE STATE ON SOUTHERLY FLOW.
OUTLOOK...
FRI...WINDY. AM SHRA/LOW CIGS POSS.
SAT-MON...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD/STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
436 AM EST THU FEB 20 2014
.SYNOPSIS...
HIGH PRESSURE OVER CENTRAL PENNSYLVANIA EARLY THIS MORNING WILL
SLIDE EAST AND MOVE OFF THE MID-ATLANTIC COAST BY THIS AFTERNOON.
A WARM FRONT WILL LIFT NORTH ACROSS THE AREA EARLY TONIGHT...BEFORE
A STRONG COLD FRONT RACES EAST ACROSS THE COMMONWEALTH EARLY FRIDAY.
TEMPERATURES SHOULD AVERAGE NEAR OR SLIGHTLY ABOVE NORMAL INTO
WEEKEND BEFORE TRENDING COLDER INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY AM MODIS 11-3.7UM IMAGERY SHOWING EXTENSIVE VALLEY FOG AND
STRATUS ACROSS NORTHWEST PA...THE RESULT OF CLEAR SKIES AND CALM
WIND UNDER HIGH PRES SYSTEM. LAMP AND RAP DATA BOTH INDICATE AREAS
OF FOG WILL LIFT BTWN 12Z-14Z. FOCUS WILL THEN BE ON BAND OF SHRA
LIFTING NORTHEAST FROM THE OHIO VALLEY ALONG APPROACHING WARM
FRONT. REGIONAL RADAR MOSAIC ALREADY SHOWING THIS DEVELOPING BAND
OF RAIN ACROSS ILLINOIS/INDIANA...WHERE NOSE OF LL JET INTERSECTS
RETREATING 8H BAROCLINIC ZONE. ALL NEAR TERM MDL DATA TIMES THIS
FEATURE THRU CENTRAL PA BTWN 17Z-23Z. ENSEMBLE MFLUX VALUES AND
QPF PROBS SUPPORT NEAR 100 PCT CHC OF RAIN ACROSS THE NW
MTNS...WITH PROGRESSIVELY LOWER CHC OF SHOWERS FURTHER SE.
EARLY SUNSHINE WILL FADE BEHIND LOWERING/THICKENING CLOUD COVER
TODAY. HOWEVER...A RELATIVELY MILD START TO THE DAY...COMBINED
WITH DEVELOPING SOUTHERLY FLOW WEST OF RETREATING HIGH PRES SHOULD
PUSH READINGS INTO THE 40S BY AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
A STRONG MID-LVL TROUGH ENTERING THE PLAINS STATES THIS AM IS
FCST TO TAKE ON A NEGATIVE TILT AS IT REACHES THE UPPER GRT LKS
AND MS/OH VLYS TNGT. THE MAIN SYNOPTIC FEATURE OF INTEREST WILL
BE THE SHARP/TRAILING COLD FRONT WHICH WILL BE CROSSING THE
APPLCHNS AROUND 12Z FRI. THIS FRONT IS EXPECTED TO BE A FOCUS FOR
A THIN LINE OF LOW-TOPPED CONVECTION WHICH COULD REACH THE WRN
ALLEGHENIES EARLY FRI MORNING.
SPC CONVECTIVE OUTLOOKS PLACE THE AREA IN GENERAL RISK...AND
MENTIONED THIS POTENTIAL FOR LOW TOPPED SQUALL LINE WITH ELEVATED
INSTABILITY IN HWO ALONG WITH POTENTIAL FOR GUSTY WINDS /AS VERY
POTENT LLJET DEVELOPS/. THE SYSTEM IS PROGRESSIVE WHICH WILL LIMIT
HVY RAIN POTNL/FLOOD THREAT...HOWEVER ICE JAM EFFECTS COULD BE A
CONCERN. ATTM DO NOT ANTICIPATE RAPID SNOW-MELT.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS COLD FRONT SLIDES ACROSS ON FRI...PRECIP WILL PUSH EASTWARD
AND COOLER AIR WILL FILTER BACK INTO THE REGION. GFS/ECMWF NOW IN
QUITE GOOD ALIGNMENT WITH MAIN FEATURES AS THIS SYSTEM
EVOLVES...WITH PRECIP ENDING BY LUNCHTIME FRI.
AFTER THAT...BROAD TROUGH BECOMES MORE AND MORE ENTRENCHED ACROSS
EASTERN 2/3RDS OF U.S. THROUGH NEXT MIDWEEK...GIVING US A SLOW
AND STEADY RETURN BACK TO BELOW NORMAL TEMPERATURES. FOR THE
UPCOMING WEEKEND...WEAK FRONT PUSHES THROUGH THAT MAY BRING LIGHT
ACCUMS OF SNOW. OTHERWISE...NO BIG SYSTEMS THROUGH TUE AS
PERSISTENT NW FLOW CONTINUES WHILE HUDSON BAY LOW GRADUALLY
DEEPENS AND PUSHES COLDER AIR FURTHER SOUTHWARD. SNOWFLAKES WILL
LINGER OVER THE WESTERN/NORTHERN HIGHER TERRAIN.
NOTABLE WAVE PROGGED TO SWING AROUND THE TROUGH NEXT MIDWEEK...AND
LONG RANGE MODELS /BOTH ECMWF AND GFS/ BEGINNING TO HINT AT
POTENTIAL LOW DEVELOPMENT AS IT SLIDES OFF THE EAST COAST. BUT THAT
REMAINS A LONG WAY OFF FOR NOW.
AS FAR AS THE SNOW COVER AND RIVER ICE...WARMING TREND LATE THIS
WEEK WILL BE FAIRLY SHORT-LIVED...SO MELTING OF SNOW AND ICE WILL
REMAIN GRADUAL...WHICH SHOULD KEEP POTENTIAL FOR WIDESPREAD
PROBLEMS LOW.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
MCLEAR SKIES AND LGT WIND UNDERNEATH HIGH PRES SYSTEM WILL PRODUCE
CONDS FAVORABLE FOR PATCHY RADIATION FOG EARLY THIS MORNING. BASED
ON 06Z DWPT DEPRESSIONS...KBFD APPEARS MOST SUSCEPTIBLE TO A
PERIOD OF IFR VSBYS EARLY THIS AM. HOWEVER...THICKENING CIRRUS
APPROACHING FROM NORTHERN OHIO COMPLICATES MATTERS AND COULD
MITIGATE THE FOG THREAT. ELSEWHERE...SREF AND OPER MDL SFC RH
FIELDS SUGGEST A DIMINISHING WIND COULD PRODUCE A BRIEF PERIOD OF
FOG ARND KMDT/KLNS ARND 12Z.
ANY PATCHY FOG SHOULD LIFT BTWN 12Z-14Z...WITH WIDESPREAD VFR
CONDS EXPECTED OVER MOST OF CENTRAL PA FOR MOST OF THE DAYLIGHT
HOURS. A BAND OF SHRA ASSOC WITH A WARM FRONT WILL LIKELY LIFT
THRU THE AREA DURING THE AFTN...AFFECTING MAINLY NW PA WHERE MVFR
REDUCTIONS ARE LIKELY AT KBFD.
A STRONG CORE OF SOUTHERLY WINDS ALOFT WILL OVERSPREAD THE REGION
THIS EVENING IN ADVANCE OF AN APPROACHING COLD FRONT. THIS WILL
LIKELY LEAD TO LLWS CRITERIA...ESP ACROSS THE W MTNS. MDL
SOUNDINGS ALSO SUPPORT THE IDEA OF WIDESPREAD MVFR /POSS IFR/ CIGS
DEVELOPING THIS EVENING IN RESPONSE TO A SURGE OF MOISTURE WORKING
INTO THE STATE ON SOUTHERLY FLOW.
OUTLOOK...
FRI...WINDY. AM SHRA/LOW CIGS POSS.
SAT-MON...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD/STEINBUGL
LONG TERM...RXR
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1008 PM PST Wed Feb 19 2014
.SYNOPSIS...
A fast moving disturbance will bring a swath of snow to northeast
Washington and north Idaho early Thursday morning followed by more
gusty winds Thursday afternoon. Snow showers are expected to
linger over the mountains on Friday, but there should be less
wind. The weekend is expected to be colder than average with
chance for snow, mainly over the mountains.
&&
.DISCUSSION...
Evening update: main adjustment was to slow the timing of the
winter weather advisories and overall precipitation onset with the
incoming system. The latest HRRR and other short-range guidance
that came in shows the main threat begins overnight (somewhere in
the 08-11Z time frame.) It looks like a quick mover and much of it
should be slipping into the northeast WA and Panhandle mountains
by mid-morning. However a messy commute time in the larger
populated Spokane/C`dA area and Palouse remains a good threat. /J. Cote`
&&
.AVIATION...
06Z TAFs: VFR conditions at all TAF sites expected this evening
through 08-10Z. After ad through 14z-16Z a warm front and swiftly
trailing occluded front will move through the region bringing a 3
to 5 hour period of likely IFR visibilities and ceilings in light
snow to the KGEG,KSFF,KCOE and KPUW TAF sites. A shorter period of
MVFR or possible IFR conditions in -SN is possible at KEAT between
08Z and 12Z. KMWH is likely to be skipped by precipitation and
KLWS may receive some MVFR ceilings and vis as the front passes.
Otherwise conditions will improve quickly after the occlusion
passes with a mainly orographic lingering shower regime which may
impact the KGEG area TAF sites with brief MVFR conditions during
the unstable afternoon period. Breezy to windy conditions in the
afternoon expected, before gradually dissipating after 00-03Z. /J.
Cote`
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 28 41 26 35 21 34 / 90 100 30 10 10 10
Coeur d`Alene 28 39 25 34 18 32 / 70 100 50 20 10 10
Pullman 29 41 27 36 23 34 / 70 80 30 20 10 0
Lewiston 32 48 32 45 28 41 / 50 50 20 30 10 0
Colville 26 41 23 37 17 35 / 80 90 60 20 10 10
Sandpoint 23 37 24 34 17 32 / 50 100 80 20 20 10
Kellogg 25 35 24 32 18 30 / 60 100 80 40 30 10
Moses Lake 32 48 29 44 25 40 / 40 10 0 0 10 10
Wenatchee 29 44 28 42 23 39 / 60 20 0 0 10 10
Omak 28 41 23 38 20 35 / 80 20 10 0 10 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory from 2 AM to 4 PM PST Thursday for
Central Panhandle Mountains.
Winter Weather Advisory from 1 AM to 8 AM PST Thursday for Coeur
d`Alene Area-Idaho Palouse.
Winter Weather Advisory from 1 AM to 10 AM PST Thursday for
Northern Panhandle.
WA...Winter Weather Advisory from 1 AM to 8 AM PST Thursday for
Spokane Area-Washington Palouse.
Winter Weather Advisory from 1 AM to 10 AM PST Thursday for
Northeast Mountains.
Winter Weather Advisory until 10 AM PST Thursday for East Slopes
Northern Cascades.
Winter Weather Advisory until 4 PM PST Thursday for Northeast
Blue Mountains.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
358 AM CST THU FEB 20 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 358 AM CST THU FEB 20 2014
POWERFUL/DANGEROUS WINTER STORM IMPACTS THE AREA TODAY INTO FRIDAY.
CURRENTLY SEEING SOME LIGHT/MOSTLY LIQUID FORM PRECIPITATION WORKING
NORTHEAST WARD INTO PORTIONS OF NORTHEAST IA/SOUTHWEST WI EARLY THIS
MORNING. THIS IS IN RESPONSE TO A MID-LEVEL TROUGH AHEAD OF THE
POTENT TROUGH AND STRONG SURFACE CYCLOGENESIS TAKING PLACE OVER THE
SOUTHERN PLAINS. LOOK FOR THIS FIRST AND ASSOCIATED RAIN/SLEET/SNOW
TO EXIT EAST THIS MORNING. THERE MAY BE A A LULL IN THE ACTION BY
MID-MORNING..TRANSITIONING TO MORE OF A DRIZZLE. EXPECTING SOME
LIGHT ICING ON ROADWAYS/SIDEWALKS WHERE TEMPERATURES WILL BE AT OR
EVEN BELOW FREEZING.
THEN...LOOK FOR THE MAIN/POWERFUL STORM SYSTEM TO LIFT FROM THE
SOUTHERN PLAINS TO JUST EAST OF GRANT COUNTY IN SOUTHWEST WI BY
00Z/6PM. AS THE LOW APPROACHES...MODEL SHOW MAXIMUM TEMPERATURES
ALOFT INCREASING INTO THE +3 TO +8C RANGE ACROSS A SMALL PART OF
NORTHEAST IA INTO SOUTHWEST AND CENTRAL WI. AS A RESULT...MUCH OF
THE PRECIPITATION FALLING ACROSS THIS AREA TODAY WILL BE IN THE FORM
OF RAIN. MEANWHILE...FARTHER WEST ACROSS NORTHEAST IA/SOUTHEAST
MN/NORTHWEST WI...TEMPERATURE PROFILES SUPPORT SNOW. THIS WILL BE
MAINLY NORTHWEST OF A LINE FROM NEW HAMPTON IA/PRESTON MN/WINONA
LINE. STRONG FRONTOGENESIS/NEGATIVE EPV SUPPORTS THE THREAT FOR
THUNDERSNOW AND INTENSE SNOW RATES EASILY 1 IN/HR THIS AFTERNOON. IN
ADDITION...STRONG NORTHWEST WINDS WILL BE KICKING IN BY LATER THIS
AFTERNOON ON THE BACKSIDE OF THE DEEP 982MB LOW. THINKING THIS AREA
SHOULD SEE SNOWFALL IN THE 5-8 INCH RANGE IN THE NOON TO 6 PM
TIMEFRAME. IN ADDITION...STRONG NORTHWEST WINDS WILL BE KICKING IN
LATER IN THE AFTERNOON FOR WIDESPREAD BLOWING AND DRIFTING AND
OCCASIONAL WHITEOUT CONDITIONS.
LOOK FOR THE HEAVY SNOW TO CONTINUE THROUGH THE EVENING OVER
NORTHEAST IA/SOUTHEAST MN INTO NORTHERN WI TONIGHT AS THE LOW PULLS
TOWARD LAKE SUPERIOR BY 6 AM. PRECIPITATION WILL TRANSITION QUICKLY
TO ALL SNOW ACROSS THE REST OF THE AREA AS COLDER AIR IS DRAWN IN BY
THE SYSTEM. VERY STRONG/GUSTY NORTHWEST WINDS WILL BE IN PLACE
ACROSS THE ENTIRE AREA WITH GUSTS APPROACHING 50 MPH ACROSS THE MORE
OPEN AREAS OF NORTHEAST IA/SOUTHEAST MN...CONTINUING THE BLOWING AND
DRIFTING. LOOK FOR THE SNOW TO SLOWLY TAPER LATER TONIGHT/AFTER
MIDNIGHT THROUGH FRIDAY MORNING FROM SOUTH TO NORTH AS THE LOW PULLS
INTO THE U.P...BUT STRONG GUSTY WINDS WILL CONTINUE TO CAUSE BLOWING
AND DRIFTING PROBLEMS.
BY THE TIME ALL IS SAID AND DONE AROUND NOON FRIDAY...6-12 INCH SNOW
ACCUMULATIONS CAN BE EXPECTED ACROSS PORTIONS OF NORTHEAST
IA/SOUTHEAST MN INTO NORTH CENTRAL WI.
DUE TO THE COMPLEXITY OF THE THERMAL PROFILE OF THIS POWERFUL STORM
AND AFFECT IT HAS ON SNOWFALL AMOUNTS AND PRECIPITATION
TYPES...HEADLINES WERE ADJUSTED/EXTENDED OVERNIGHT.
FOR FULL DETAILS INCLUDING WINTER WEATHER HEADLINES/GRAPHICAL
DISPLAY OF SNOW AMOUNTS AND OTHER HAZARDS TIED TO THE STORM...SEE
OUR NEWS STORY ON OUR INTERNET PAGE AT WWW.WEATHER.GOV/LACROSSE.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 400 AM CST THU FEB 20 2014
WITH THE DEPARTING STORM SYSTEM FRIDAY...LOOK FOR COLDER NORTHWEST
FLOW ALOFT TO KICK IN INTO NEXT WEEK. UNSEASONABLY COLD TEMPERATURES
WILL RESULT WITH HIGHS SATURDAY STARTING OFF IN THE TEENS AND LOWER
20S...THEN DROPPING INTO THE UPPER SINGLE DIGITS AND TEENS ABOVE ZERO
BY WEDNESDAY. OVERNIGHT LOWS ARE EXPECTED TO DIP INTO THE SINGLE
DIGITS ABOVE AND BELOW ZERO...POSSIBLY TEEN/NEAR 20 BELOW BY
WEDNESDAY NIGHT. ALSO...APPEARS THERE WILL BE A SHOT AT SOME LIGHT
SNOW MONDAY/MONDAY NIGHT TIME FRAME AS A WEAK MID-LEVEL TROUGH
ROTATES THROUGH THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1122 PM CST WED FEB 19 2014
NO SIGNIFICANT FORECAST CHANGES EXPECTED BASED ON THE LATEST MODEL
INFORMATION. REGIONAL RADARS SHOWING THE FIRST WAVE OF
PRECIPITATION OCCURRING OVER SOUTHERN IOWA MOVING NORTHEAST. THE
20.00Z NAM AND 20.03Z HRRR SHOW THE BULK OF THIS PRECIPITATION
MOVING PAST THE TAF SITES TO THE SOUTHEAST. STILL EXPECTING SOME
LIGHT PRECIPITATION TO HIT THE TAF SITES AS THIS COMES IN AND THE
CONCERN REMAINS WHETHER THERE WILL BE ICE AVAILABLE IN THE CLOUDS
AND IF THERE IS...WILL THE WARM LAYER ABOVE THE SURFACE BE ENOUGH
FOR COMPLETE OR PARTIAL MELTING. HAVE CONTINUED THE TREND OF
SHOWING LIGHT SNOW WITH A PERIOD OF FREEZING RAIN AND SLEET
POSSIBLE AT KLSE AND INTRODUCED THE FREEZING RAIN THREAT AT KRST
AS WELL. BY MID MORNING...LOW LEVEL TEMPERATURES STILL EXPECTED TO
BE WARM ENOUGH FOR A RAIN/SNOW MIX AT KLSE WHILE PRIMARILY SNOW IS
EXPECTED AT KRST. THIS INITIAL PRECIPITATION SHOULD PRODUCE
PRIMARILY MVFR CONDITIONS. CONDITIONS THEN DETERIORATE RAPIDLY
DURING THE AFTERNOON AS THE STRONG FORCING MOVES IN WITH MODERATE
TO HEAVY SNOW AND IFR CONDITIONS INTO THE EVENING HOURS. ONCE THE
SURFACE LOW MOVES PAST...THE FALLING SNOW WILL START TO DECREASE
IN INTENSITY BUT THE WINDS WILL BECOME STRONG OUT OF THE WEST WITH
GUSTS OF 30 TO 40 KNOTS WHICH WILL PRODUCE BLOWING SNOW AT BOTH
AIRPORTS AND KEEP KRST IN IFR CONDITIONS.
.HYDROLOGY...(FOR TODAY INTO EARLY THIS EVENING)
ISSUED AT 358 AM CST THU FEB 20 2014
WITH WARMER AIR WRAPPING INTO THIS INTENSE LOW...MORE RAINFALL WILL
BE SEEN ACROSS SOUTHWEST INTO CENTRAL WI. WITH FROZEN GROUND AND
SEWERS PLUGGED WITH ICE/SNOW...LOOK FOR PONDING OF WATER AND SOME
RUNOFF INTO STREAMS FOR LOCAILZED RISES WHERE STREAM ARE RUNNING
UNFROZEN.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL NOON CST FRIDAY FOR WIZ041>044-
053>055-061.
WINTER STORM WARNING FROM 9 AM THIS MORNING TO NOON CST FRIDAY
FOR WIZ017-029-032>034.
MN...WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR
MNZ086>088-094-095.
BLIZZARD WARNING FROM 9 AM THIS MORNING TO NOON CST FRIDAY FOR
MNZ079-086-087-094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST FRIDAY FOR MNZ096.
WINTER STORM WARNING FROM 9 AM THIS MORNING TO NOON CST FRIDAY
FOR MNZ088.
IA...WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR
IAZ008>010-018-019-029.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1122 PM CST WED FEB 19 2014
.UPDATE...
ISSUED AT 741 PM CST WED FEB 19 2014
DID A REWORK OF THE WEATHER TYPES FOR TONIGHT INTO THURSDAY
MORNING. LOOKING AT THE FORECAST SOUNDINGS FROM BOTH THE 19.18Z
NAM AND GFS...THERE IS A POTENTIAL FOR A REAL MIXED BAG OF
PRECIPITATION TYPES. THERE MAY OR MAY NOT BE ICE IN THE CLOUDS FOR
SOME PARTS OF THE AREA AND TEMPERATURES ALOFT WILL BE WARMING THAT
COULD MELT OR PARTIALLY MELT THE FALLING SNOW IF THERE IS ICE.
PREVIOUS THINKING WAS THIS MIX COULD EXTEND NORTH TO ABOUT THE I90
CORRIDOR AND ESSENTIALLY MADE OUR WEATHER TYPES AGREE WITH WHAT
WAS BEING TALKED ABOUT IN OUR TEXT PRODUCTS. BEST POTENTIAL FOR
ICING WILL BE ACROSS THE FAR SOUTHERN SECTIONS OF THE AREA WHERE
UP TO A TENTH OF ICE IS POSSIBLE FROM FAYETTE ACROSS CLAYTON INTO
GRANT COUNTIES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 328 PM CST WED FEB 19 2014
DANGEROUS WINTER STORM TO IMPACT THE AREA THURSDAY AFTERNOON INTO
THURSDAY NIGHT.
STRONG LOW PRESSURE WILL DEVELOP OVER THE CENTRAL PLAINS TONIGHT AND
IS EXPECTED TO START TRACKING NORTHEAST TOWARD THE UPPER
MISSISSIPPI RIVER VALLEY. WARM AIR ADVECTION OVERSPREADS THE
REGION TONIGHT AHEAD OF THE DEVELOPING SYSTEM AND WILL LEAD TO A
WINTRY MIX OF FREEZING RAIN...SLEET AND SNOW. THE BULK OF THE
PRECIPITATION TONIGHT WILL OCCUR ALONG AND SOUTH OF THE INTERSTATE
90 CORRIDOR. LIGHT ICE ACCUMULATIONS OF AROUND 1/10 OF AN INCH ARE
POSSIBLE MAINLY OVER PORTIONS OF NORTHEAST IOWA INTO FAR
SOUTHWEST WISCONSIN. THIS LIGHT ICING WILL LEAD TO A SLICK
THURSDAY MORNING COMMUTE.
THE MAIN SYSTEM LIFTS INTO THE AREA THURSDAY AFTERNOON WITH
CONDITIONS RAPIDLY DETERIORATING DURING THE EARLY AFTERNOON HOURS.
LOOK FOR HEAVY SNOW TO OVERSPREAD THE REGION WITH SNOWFALL RATES
OF 1 TO 2 INCHES PER HOURS LIKELY. TRAVEL CONDITIONS WILL BECOME
DANGEROUS BY LATE THURSDAY AFTERNOON. AS THE CYCLONE LIFTS INTO
SOUTHERN WISCONSIN DURING THE LATE AFTERNOON AND EARLY EVENING
NORTHWEST WINDS WILL INCREASE TO 25 TO 35 MPH ON THE BACK SIDE OF
THE LOW...LEADING TO BLIZZARD CONDITIONS ACROSS OPEN AREAS. THERE
REMAINS SOME UNCERTAINTY ON SNOW ACCUMULATIONS OVER PORTIONS OF
CENTRAL WISCONSIN WHERE WARMER AIR WILL KEEP MORE OF A
RAIN/SLEET/SNOW MIX GOING INTO THE EARLY EVENING HOURS. DECIDED TO
INCLUDE GRANT COUNTY IN THE WINTER STORM WARNING WHERE AROUND 3.5
INCHES OF SNOW AND THE STRONG NORTHWEST WINDS WILL LEAD TO NEAR
BLIZZARD CONDITIONS AT TIMES. THE MORE SHELTERED LOCATIONS OVER
CENTRAL WISCONSIN ARE EXPECTED TO SEE SNOW AMOUNTS OF 1 TO 3
INCHES OF SNOW AND SLIGHTLY LIGHTER WIND SPEEDS. HAVE SIDED WITH
THE ECMWF/GFS FOR THE LOW TRACK TONIGHT. IF THE SYSTEM WOULD SLIDE
SLIGHTLY FURTHER EAST...RICHLAND...ADAMS...AND JUNEAU COUNTIES
WOULD LIKELY NEED TO BE UPGRADED TO A WINTER STORM WARNING.
FURTHER TO THE WEST...OVER MUCH OF NORTHEAST IOWA...SOUTHEAST
MINNESOTA...AND WEST CENTRAL INTO NORTH CENTRAL WISCONSIN...SNOW
ACCUMULATIONS OF 6 TO 10 INCHES ARE EXPECTED. ROADS WILL LIKELY
BECOME IMPASSABLE...ESPECIALLY ACROSS THE OPEN AREAS OF SOUTHEAST
MINNESOTA INTO NORTHEAST IOWA FROM THE DRIFTING SNOW.
ALSO...VISIBILITIES WILL BE REDUCED TO ZERO AT TIMES. THE LOW
FINALLY OCCLUDES AND LIFTS NORTH OVER LAKE SUPERIOR LATE THURSDAY
NIGHT INTO EARLY FRIDAY MORNING WITH SNOW TAPERING OFF.
HOWEVER...STRONG NORTHWEST WINDS WILL CONTINUE TO PRODUCE AREAS OF
BLOWING AND DRIFTING SNOW...IMPACTING THE FRIDAY MORNING COMMUTE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 328 PM CST WED FEB 19 2014
COOL HIGH PRESSURE BUILDS BACK INTO THE REGION LATE FRIDAY INTO
SATURDAY AND REMAINS OVER THE REGION THROUGH THE WEEKEND. PLAN ON
QUIET WEATHER WITH HIGHS IN THE TEENS TO LOWER 20S AND LOWS IN THE
SINGLE DIGITS ABOVE AND BELOW ZERO. THE NEXT CHANCE FOR SNOW MOVES
ACROSS THE AREA MONDAY INTO MONDAY NIGHT...BUT LATEST TRENDS
APPEAR THAT IT MAY TRACK JUST SOUTH OF THE FORECAST AREA. COLD
HIGH PRESSURE LOOKS TO MAKE A RETURN TUESDAY NIGHT WITH LOWS
FALLING INTO THE SINGLE DIGITS TO TEENS BELOW ZERO. EVEN COLDER
TEMPERATURES ARE POSSIBLE WEDNESDAY NIGHT WHEN LOWS COULD FALL
INTO THE TEENS BELOW ZERO ACROSS THE ENTIRE FORECAST AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1122 PM CST WED FEB 19 2014
NO SIGNIFICANT FORECAST CHANGES EXPECTED BASED ON THE LATEST MODEL
INFORMATION. REGIONAL RADARS SHOWING THE FIRST WAVE OF
PRECIPITATION OCCURRING OVER SOUTHERN IOWA MOVING NORTHEAST. THE
20.00Z NAM AND 20.03Z HRRR SHOW THE BULK OF THIS PRECIPITATION
MOVING PAST THE TAF SITES TO THE SOUTHEAST. STILL EXPECTING SOME
LIGHT PRECIPITATION TO HIT THE TAF SITES AS THIS COMES IN AND THE
CONCERN REMAINS WHETHER THERE WILL BE ICE AVAILABLE IN THE CLOUDS
AND IF THERE IS...WILL THE WARM LAYER ABOVE THE SURFACE BE ENOUGH
FOR COMPLETE OR PARTIAL MELTING. HAVE CONTINUED THE TREND OF
SHOWING LIGHT SNOW WITH A PERIOD OF FREEZING RAIN AND SLEET
POSSIBLE AT KLSE AND INTRODUCED THE FREEZING RAIN THREAT AT KRST
AS WELL. BY MID MORNING...LOW LEVEL TEMPERATURES STILL EXPECTED TO
BE WARM ENOUGH FOR A RAIN/SNOW MIX AT KLSE WHILE PRIMARILY SNOW IS
EXPECTED AT KRST. THIS INITIAL PRECIPITATION SHOULD PRODUCE
PRIMARILY MVFR CONDITIONS. CONDITIONS THEN DETERIORATE RAPIDLY
DURING THE AFTERNOON AS THE STRONG FORCING MOVES IN WITH MODERATE
TO HEAVY SNOW AND IFR CONDITIONS INTO THE EVENING HOURS. ONCE THE
SURFACE LOW MOVES PAST...THE FALLING SNOW WILL START TO DECREASE
IN INTENSITY BUT THE WINDS WILL BECOME STRONG OUT OF THE WEST WITH
GUSTS OF 30 TO 40 KNOTS WHICH WILL PRODUCE BLOWING SNOW AT BOTH
AIRPORTS AND KEEP KRST IN IFR CONDITIONS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
WIZ041-042-053-054-061.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
WIZ017-029-032>034-041-042-053-054-061.
WINTER WEATHER ADVISORY FROM 3 AM THURSDAY TO 6 AM CST FRIDAY
FOR WIZ043-044-055.
MN...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
MNZ086>088-094>096.
BLIZZARD WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
MNZ079-086-087-094-095.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
MNZ088-096.
IA...WINTER WEATHER ADVISORY FROM 3 AM TO 9 AM CST THURSDAY FOR
IAZ008>011-018-019-029-030.
BLIZZARD WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
IAZ008>010-018-019-029.
WINTER STORM WARNING FROM 9 AM THURSDAY TO 6 AM CST FRIDAY FOR
IAZ011-030.
&&
$$
UPDATE...04
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...04
AREA FORECAST DISCUSSION
NWS ALBANY NY
944 AM EST THU FEB 20 2014
.SYNOPSIS...
A POWERFUL STORM WILL DEVELOP OVER THE CENTER OF THE NATION AND
TRACK NORTHWARD ACROSS THE GREAT LAKES REGION TONIGHT. ITS
ASSOCIATED WARM FRONT WILL PROVIDE A PERIOD OF WINTRY
PRECIPITATION FOR MANY AREAS TONIGHT. HOWEVER..WARMER AIR WILL
EVENTUALLY LIFT NORTHWARD TO RESULT IN MOSTLY RAIN FRIDAY ALONG
WITH A CHANCE FOR A THUNDERSTORM. A STRONG COLD FRONT PASSES
ACROSS THE AREA FRIDAY AFTERNOON WITH A RETURN TO COOLER WEATHER
FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 944 AM EST...JUST SOME MINOR CHANGES FOR THE REST OF TODAY.
TEMPERATURES ARE RISING RATHER QUICKLY THIS MORNING...EVEN FOR
AREAS THAT WERE COLDER EARLIER THIS MORNING DUE TO PLENTY OF
SUNSHINE AND A WARMING SOUTHWEST FLOW ALOFT. SO CURRENT
TEMPERATURE FORECAST LOOKS TO BE ON TRACK WITH ALL AREAS EXPECTED
TO REACH WELL ABOVE FREEZING THIS AFTERNOON. OTHERWISE...HIGH AND
MID LEVEL CLOUDS WILL GRADUALLY INCREASE THROUGH THE REST OF THE
DAY AHEAD OF A WARM FRONT APPROACHING FROM THE OHIO VALLEY AND
GREAT LAKES REGION.
UPSTREAM ELEVATED CONVECTIVE ACTIVITY CONTINUES TO BE RATHER
IMPRESSIVE WITH A SMALL-SCALE MCS APPROACHING MOVING THROUGH
IL/IN/OH/MI AREA. LATEST HRRR REFLECTIVITY FORECASTS SUGGEST
REMNANTS OF THIS ACTIVITY FORCED BY INCREASING ISENTROPIC LIFT
AND ENHANCED 2D FGEN...WILL MOVE INTO OUR AREA TOWARD THE 22-00Z
TIME FRAME. THERMAL PROFILES STILL LOOK RATHER CHILLY FOR THE
NORTHERN 2/3RDS WITH SNOW MIXING WITH SLEET AND FREEZING RAIN AS
NO CHANGES TO THE CURRENT HEADLINES.
H2O VAPOR IMAGERY REVEALS A VERY POTENT SHORT WAVE EJECTING OUT
ONTO THE CENTRAL PLAINS. MEANWHILE...A SUBTROPICAL PLUME OF
MOISTURE EXTENDED FROM THE CENTRAL PACIFIC...ACROSS BAJA
CALIFORNIA AND ONTO THE SOUTHERN PLAINS AND MID WEST. PWATS WITHIN
THIS DEEPER MOISTURE WAS BETWEEN 1-3 STANDARD DEVIATIONS ABOVE
NORMAL AS NCEP MODEL SUITE AND SHORT TERM GUIDANCE /RUC13-HRRR/
SUGGEST A RAPID INCREASE IN MOISTURE TRANSPORT EVOLVING THROUGH
THE DAY TODAY. LOW LEVEL JET GREATER THAN 50KTS IS ALSO EXPECTED
TO DEVELOP TO ASSIST WITH THE MOISTURE TRANSPORT NORTHWARD INTO
OUR CWA BY LATE THIS AFTERNOON. THERMAL PROFILES FROM BUFR
PROFILES SUGGEST A RAIN/SNOW LINE SOMEWHERE ALONG OR JUST SOUTH OF
I90 PER WET BULB ZERO.
CROSS SECTIONS TONIGHT POINT TOWARD ANOTHER IMPRESSIVE 2D FGEN
ENHANCEMENTS AS PER CSTAR RESEARCH SUGGESTS BANDED STRUCTURES TO
THE PRECIP DEVELOPING OVER THE REGION. PER THE NCEP MODEL
SUITE...THIS BAND WILL MIGRATE FROM SOUTH TO NORTH THROUGH THIS
EVENING AND MAY LINGER ACROSS PORTIONS OF THE ADIRONDACKS
OVERNIGHT. IN ADDITION...INCREASING SOUTHERLY FLOW FAVORS UPSLOPE
CONDITIONS FURTHER ENHANCING THE PRECIP AMOUNTS. AS FOR
PRECIP...THERMAL PROFILES ARE TRICKY. WITHIN THE VICINITY OF I90
CORRIDOR...THE INITIAL ONSET OF PRECIP WILL LIKELY BE A RAIN/SNOW
TO SNOW THIS EARLY EVENING WITH A TRANSITION TO SLEET AND PERHAPS
A PERIOD OF FREEZING RAIN THROUGH THE LATER EVENING HOURS AS
WARMER AIR ALOFT /H850/ CLIMBS ABOVE FREEZING. DUE TO THE ENHANCE
2D FGEN AND A LAYER OF NEGATIVE EPV JUST ABOVE THIS LAYER WITH >20
UBAR/SEC OMEGA...THIS POINTS TOWARD THE POTENTIAL FOR AN MODERATE
TO HEAVY BAND OF PRECIP LIFTING NORTHWARD WITH A QUICK
ACCUMULATING SNOW THIS EVENING. THE BETTER CHANCE FOR A QUICK
ACCUMULATING SNOWFALL WILL BE NORTH OF I90 WHERE UP TO 4 INCHES
COULD FALL IN A SHORT PERIOD OF TIME. DUE TO THE COMPLEX THERMAL
PROFILES AND THE HIGH POTENTIAL FOR BANDED PRECIP STRUCTURES...WE
WILL HOIST ADVISORIES FOR THE NORTHERN 2/3RDS OF THE CWA. SOUTHERN
PORTIONS APPEAR TO REMAIN ABOVE FREEZING FOR MOST OF THE PRECIP TO
FALL AS RAIN. AS THE WARMER AIR CONTINUES ALOFT...THE PRECIP TO
THE NORTH OF I90 MIXING WITH SLEET AND FREEZING RAIN. THOSE LOWER
VALLEY LOCATIONS WITHIN THE MOUNTAINS COULD EXPERIENCE A PERIOD OF
ACCUMULATING ICE WITH CURRENT PROJECTIONS UP TO TWO TENTHS OF AN
INCH IN A FEW LOCATIONS WITH MOST AREA EXPECTED TO REMAIN BELOW
THAT VALUE.
TEMPERATURES WILL FOLLOW A NON-DIURNAL CURVE THE NEXT 24 HOURS AS
STRENGTHENING WARM ADVECTION UNFOLDS AS WARM FRONT LIFTS NORTHWARD.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
LOW LEVEL JET PER THE GEFS/SREF ENSEMBLES WILL RANGE BETWEEN 2-3
STANDARD DEVIATIONS ABOVE NORMAL ACROSS THE REGION ALONG WITH
THOSE HIGH PWATS FOR THIS TIME OF THE YEAR. AS TEMPERATURES
CONTINUE TO CLIMB ABOVE FREEZING...THIS WILL REDUCE THE WINTRY
MIXTURE TO MAINLY RAIN. THE FORECAST AREA IS EXPECTED TO BE WELL
WITHIN THE WARM SECTOR AS H850 TEMPS CLIMB TOWARD +8C. THIS WILL
INCREASE THE SNOW MELT ALONG WITH DEWPOINTS CLIMBING ABOVE
FREEZING. PATCHY FOG IS EXPECTED ALONG WITH THE INCREASE IN
RAINFALL POTENTIAL. IN FACT...FORECAST SOUNDINGS SUGGEST LIFTING
PARCELS ABOVE THE BOUNDARY LAYER YIELDS THE POSSIBILITY FOR
THUNDERSTORMS AS SHOWALTERS DROP BELOW 0C. IN COORDINATION WITH
SPC...WE WILL INTRODUCE A SLIGHT CHANCE FOR THUNDER ACROSS THE
ENTIRE REGION. RAINFALL RATES ALONG THE STRONG BAROCLINIC FRONTAL
ZONE COULD BE RATHER HIGH FOR THIS TIME OF THE YEAR. AT THIS
TIME...NO HYDRO RELATED HEADLINES BUT COULD SEE SOME URBAN AND
SMALL STREAM ISSUES AS PERHAPS ICE JAMS DUE TO BREAK UP /MORE
BELOW IN THE HYDRO SECTION/. TEMPERATURES FOR MOST OF THE AREA ARE
EXPECTED TO BE WELL INTO 40S. THE STRONG WINDS ALOFT SHOULD REMAIN
ABOVE THE BOUNDARY LAYER WITH NOT MUCH MIXING EXPECTED.
FROPA IS EXPECTED AROUND THE 21Z TIME FRAME. THE H850 TEMPS PLUNGE
FROM AROUND +8C TO AROUND -6C IN ABOUT 6HRS. THERE COULD A PERIOD
OF RAIN MIXING WITH A LITTLE SNOW IN THE WAKE OF THE FROPA BUT
ACCUMULATIONS ARE NOT EXPECTED FOR MOST OF THE REGION. WHERE SOME
LIGHT ACCUMULATIONS ARE POSSIBLE WILL BE ACROSS THE ADIRONDACKS AS
AN UPPER LEVEL IMPULSE ROTATES ACROSS THIS REGION AROUND THE
PERIPHERY OF THE DEEP UPPER LOW NEAR JAMES BAY AND SOME LAKE
ONTARIO CONTRIBUTION. TEMPERATURES WILL DIP BACK BELOW FREEZING
FRIDAY NIGHT AS SOME BLACK ICE COULD FORM ON THOSE UNTREATED
SURFACES.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
MUCH OF THE PERIOD WILL FEATURE THE RETURN OF BELOW NORMAL
TEMPERATURES...ALONG WITH A FEW POSSIBLE EPISODES OF SNOW SHOWERS
AND/OR LIGHT SNOW...AS MID/UPPER LEVEL HEIGHTS FALL CONSIDERABLY
ACROSS SOUTHERN AND EASTERN CANADA...INTO THE CENTRAL AND EASTERN
U.S.
HERE ARE SOME MORE SPECIFIC DETAILS...
SAT-SAT NT...IN THE WAKE OF FRIDAY/S FRONTAL SYSTEM...A BROAD
SOUTHWEST FLOW IN THE MID AND UPPER LEVELS OF THE TROPOSPHERE WILL
ALLOW FOR ONLY GRADUAL LOW LEVEL COOLING TO OCCUR. THEREFORE...WE
EXPECT TEMPS TO REMAIN ABOVE SEASONAL LEVELS ON SAT...RISING INTO
THE 40S IN MOST VALLEY AREAS...AND 30S ACROSS HIGHER ELEVATIONS. IT
IS POSSIBLE THAT SOME PORTIONS OF THE MID HUDSON VALLEY AND LOWER
ELEVATIONS IN NW CT APPROACH 50 WITH SUNSHINE AND A DOWNSLOPING
WESTERLY LOW LEVEL FLOW. IN THE AFTERNOON...A WEAK UPPER LEVEL
IMPULSE MAY BRING SOME CLOUDS...AND PERHAPS SOME LIGHT SHOWERS OF
RAIN/SNOW IN THE AFTERNOON/EVENING FOR CENTRAL AND NORTHERN AREAS.
FOR SAT NT...TEMPS WILL FALL INTO THE 20S IN MOST AREAS...WITH SOME
TEENS ACROSS THE WESTERN ADIRONDACKS...WHERE SOME SNOW SHOWERS WILL
ALSO BE POSSIBLE.
SUN-MON NT...THE TREND TOWARD COLDER TEMPS WILL CONTINUE...WITH
SUNDAY MAX TEMPS REACHING THE MID 30S TO LOWER 40S IN VALLEYS...AND
20S TO LOWER 30S ACROSS HIGHER ELEVATIONS...WHILE MONDAY MAXES ONLY
REACH THE 20S IN VALLEYS...AND TEENS ACROSS HIGHER ELEVATIONS. SOME
SNOW SHOWERS/FLURRIES WILL BE POSSIBLE ACROSS CENTRAL AND NORTHERN
AREAS LATE SUN INTO MONDAY NT. TEMPS MON NT WILL FALL INTO THE
SINGLE DIGITS IN MOST AREAS.
TUE-WED...MODEL UNCERTAINTY INCREASES WITH REGARD TO THE HANDLING OF
POTENTIAL FAST MOVING UPPER LEVEL IMPULSES DURING THIS TIME PERIOD.
THE 00Z/20 ECMWF HINTS AT ONE POSSIBLE IMPULSE AFFECTING THE REGION
TUE...ESP CENTRAL AND SOUTHERN AREAS...WITH SOME LIGHT SNOW...WHILE
THIS SIGNAL IS SOMEWHAT WEAKER IN THE 00Z/20 GFS AND GEFS. WILL
TREND TOWARD THE ECMWF SOLUTION...WITH SLIGHT CHC POPS ACROSS
CENTRAL AND SOUTHERN AREAS FOR SNOW SHOWERS...ALONG WITH SOME CHC
POPS ACROSS THE WESTERN ADIRONDACKS. BOTH THE 00Z/20 ECMWF/GFS AND
GEFS HINT AT ANOTHER IMPULSE PASSING MAINLY SOUTH OF THE REGION ON
WED...ALTHOUGH THE GEFS ARE A LITTLE FURTHER NORTH WITH POSSIBLE
MEASURABLE PRECIPITATION. WILL THEREFORE INDICATE LOW CHC POPS FOR
LIGHT SNOW ON WED. OTHERWISE...TEMPS WILL REMAIN WELL BELOW NORMAL
DURING THIS PERIOD...WITH DAYTIME MAXES MAINLY IN THE 20S FOR
VALLEYS...AND TEENS FOR HIGHER ELEVATIONS...AND OVERNIGHT MIN TEMPS
MAINLY IN THE SINGLE DIGITS TO LOWER TEENS.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
AFTER ANY FOG/LOW CLOUDS LIFT BETWEEN 12Z-14Z/THU...VFR CONDITIONS
ARE EXPECTED THROUGH AT LEAST 22Z/THU. THEREAFTER...A STRONG WARM
FRONT WILL APPROACH FROM THE SOUTHWEST. A BAND OF MODERATE TO
LOCALLY HEAVY PRECIPITATION IS EXPECTED TO DEVELOP AHEAD OF THIS
FRONT...IMPACTING KGFL THE LONGEST...AND SOMEWHAT SHORTER AT
KALB/KPSF...AND LEAST AT KPOU. P-TYPE INITIALLY SHOULD BE MAINLY
SNOW AT KGFL...AND A MIX OF SNOW/SLEET AND SOME RAIN AT KALB AND
KPSF. AS MILDER AIR ALOFT MOVES IN...SNOW SHOULD CHANGE TO A MIX OF
FREEZING RAIN AND SLEET AFTER ROUGHLY 03Z/FRI AT KGFL. AT KALB AND
KPSF...AFTER A SNOW/SLEET/RAIN MIX...P-TYPE SHOULD BECOME MAINLY
RAIN WITH PERHAPS SOME OCCASIONAL SLEET AFTER 03Z/FRI. CONDITIONS
WILL GENERALLY BE IFR IN AREAS WHERE SNOW AND SLEET INITIALLY
OCCUR...AND MVFR WITHIN ANY RAIN. HOWEVER...LATER TONIGHT...CIGS
AND VSBYS WILL LIKELY DIP INTO THE IFR/LIFR RANGE IN ALL AREAS.
WEST TO NORTHWEST WINDS AT 5-10 KT WILL BECOME LIGHT/VARIABLE AS A
HIGH PRESSURE RIDGE SLIDES ACROSS THE TAF SITES. AS THE RIDGE SHIFTS
EAST OF THE TAF SITES...WINDS WILL BECOME SOUTHEAST TO SOUTH AT 5-10
KT LATER THIS AFTERNOON INTO TONIGHT...ALTHOUGH MAY BACK INTO THE
NORTHEAST AT KGFL AFTER SUNSET. WINDS THU NT SHOULD BE MAINLY FROM
THE E TO NE...AT LESS THAN 5 KT...EXCEPT SOUTH TO SOUTHEAST AT KALB
AT 5-10 KT.
OUTLOOK...
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...FG.
FRIDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...FG.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
THE SNOW DEPTHS ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN
NEW ENGLAND ARE GENERALLY FROM 1 TO 3 FEET.
MODERATING TEMPERATURES REMAIN IN THE FORECAST WHICH WILL REACH
ITS PEAK DURING FRIDAY. SNOW MELT WILL INITIALLY BE SMALL AT FIRST
WITH A GRADUAL INCREASE DURING FRIDAY.
RAINFALL TOTALS TONIGHT AND FRIDAY ARE FORECAST TO GENERALLY BE
IN THE HALF AN INCH TO ONE INCH RANGE BASED ON THE LATEST
NERFC/WPC GUIDANCE. THE HIGHER TOTALS ARE EXPECTED ACROSS THE SRN
DACKS REGION...WHERE ISOLATED AMOUNTS TO AN INCH AND A HALF ARE
POSSIBLE. THERE WILL BE A PERIOD OF WINTRY MIXTURE AT THE ONSET
AND THROUGH MOST OF TONIGHT WITH A TRANSITION TO RAIN FROM
SOUTHWEST TO NORTHEAST. WE EXPECT MUCH OF THE RAINFALL WILL SOAK
INTO THE DEEP SNOW PACK.
PER THE LATEST MMEFS...THERE IS A SMALL POTENTIAL FOR FLOODING
ACROSS THE WESTERN MOHAWK VALLEY BUT DUE TO ICE IN PLACE...FOCUS
WILL BE THE ICE JAM POTENTIAL. HOWEVER...ACCUMULATING TEMPERATURES
REMAINING ABOVE FREEZING WILL BE MINIMAL WHICH SHOULD KEEP THINGS
IN CHECK. NEVERTHELESS...IT IS NOT ZERO AS WE WILL CONTINUE TO
HIGHLIGHT WITHING THE HWO.
COLDER TEMPERATURES ARE EXPECTED FRIDAY NIGHT...AND LATER IN THE
WEEK. AN ISOLATED OR LOCALIZED ICE JAM THREAT WILL CONTINUE TO BE
MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
THE MONTHLY SNOWFALL TOTAL FOR FEBRUARY AT THE ALBANY INTERNATIONAL
AIRPORT IS AT 27.7 INCHES THROUGH THE 19TH. IT IS THE 7TH
SNOWIEST FEBRUARY ON RECORD.
TOP 10 SNOWIEST FEBRUARYS ALBANY
1. 40.7 INCHES 1893
2. 34.5 INCHES 1962
3. 32.3 INCHES 1926
4. 31.7 INCHES 1950
5. 30.1 INCHES 2011
6. 28.6 INCHES 1993
7. 27.7 INCHES 2014
8. 27.5 INCHES 1899
9. 26.1 INCHES 1914
10. 26.0 INCHES 1958
10. 26.0 INCHES 1988
LOOKING AT THE SEASONAL SNOWFALL IT STANDS AT 64.8 INCHES. NORMAL
FOR THE ENTIRE WINTER SEASON IS 59.1 INCHES.
SO HOW DOES THIS WINTER COMPARE TO RECENT WINTERS FOR ALBANY...
2012-13: 51.4 INCHES
2011-12: 23.3 INCHES
2010-11: 87.2 INCHES
2009-10: 45.4 INCHES
2008-09: 52.6 INCHES
2007-08: 61.1 INCHES
2006-07: 45.9 INCHES
2005-06: 30.2 INCHES
2004-05: 75.9 INCHES
2003-04: 65.1 INCHES
2002-03: 105.4 INCHES
2001-02: 47.4 INCHES
2000-01: 77.1 INCHES
ALBANY EXTREMES:
SNOWIEST 1970-71 WITH 112.5 INCHES
LEAST 1912-13 WITH ONLY 13.8 INCHES
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM EST
FRIDAY FOR NYZ033-039>043-048>050-082>084.
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 PM EST
THIS EVENING FOR NYZ032-038-047-051>054.
MA...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 PM EST
THIS EVENING FOR MAZ001-025.
VT...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM EST
FRIDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM/JPV
SHORT TERM...BGM
LONG TERM...KL
AVIATION...KL
HYDROLOGY...KL/BGM/WASULA
CLIMATE...NWS STAFF
AREA FORECAST DISCUSSION
NWS GOODLAND KS
325 AM MST THU FEB 20 2014
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT.)
ISSUED AT 236 AM MST THU FEB 20 2014
SNOW AND BLOWING SNOW WITH AREAS OF REDUCED VISIBILITY CONTINUE
TO MOVE ACROSS MAINLY THE EASTERN PORTION OF THE FORECAST AREA
THIS MORNING WHILE SNOW APPEARS TO BE ENDING FROM WEST TO EAST
ACROSS FAR EASTERN COLORADO. AM RELUCTANT TO TRIM OFF THE WESTERN
PORTION OF THE WINTER WEATHER ADVISORY TOO EARLY AS WINDS ARE
STILL STRONG ENOUGH TO PRODUCE AREAS OF BLOWING SNOW AND REDUCED
VISIBILITIES.
EXPECT SNOW TO CONTINUE TO MOVE EAST OUT OF THE FORECAST AREA
QUICKLY THIS MORNING AND WILL CONTINUE TO EVALUATE THE POSSIBLE
NEED FOR EXPANSION OF THE ADVISORY IN TIME ACROSS THE EAST THIS
MORNING AND THE POSSIBLE TRIMMING OF THE ADVISORY AREAS ACROSS
THE WEST.
EXPECT THE WINDS TO DECREASE SOMEWHAT THIS MORNING FOLLOWING
SUNRISE AND TO RE-INTENSIFY THROUGH THE MORNING. WILL LEAVE THE
WIND ADVISORY INTACT ACROSS THE ENTIRE FORECAST AREA AS A RESULT.
NORTHWEST WINDS DECREASE RAPIDLY LATE THIS AFTERNOON AND
EVENING AND TURN MORE WESTERLY OVERNIGHT TONIGHT.
WARMER TEMPERATURES ARE EXPECTED ON FRIDAY WITH COOLER
TEMPERATURES SATURDAY WITH A CHANCE OF LIGHT SNOW MOVING INTO THE
AREA FROM THE NORTH ON SATURDAY NIGHT AS THE JET STREAM POSITIONED
ACROSS THE NORTHERN PLAINS BRINGS WEAK IMPULSES EAST OF THE
ROCKIES.
.LONG TERM...(SUNDAY THROUGH NEXT THURSDAY)
ISSUED AT 1206 AM MST THU FEB 20 2014
A LONGWAVE TROUGH WILL BE OVER THE NORTHERN PLAINS AND GREAT LAKES
WITH A SERIES OF SHORTWAVE TROUGHS MOVING THROUGH. THIS WILL
RESULT IN NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES AND
OCCASIONAL CHANCES FOR LIGHT SNOW. THESE SYSTEMS ARE ALL VERY WEAK
AND PRODUCE AN INCH OR LESS OF SNOW. HIGH TEMPERATURES WILL
GENERALLY BE IN THE 30S AND 40S WITH LOWS IN THE TEENS AND 20S. AT
THE VERY END OF THE LONG TERM PERIOD...COLDER AIR MAY BE TAPPED BY
A SOUTHERN STREAM SYSTEM WHICH COULD RESULT IN MUCH BELOW NORMAL
TEMPERATURES FOR THE END OF NEXT WEEK AND BETTER CHANCES OF SNOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1040 PM MST WED FEB 19 2014
VFR CONDITIONS FOR KGLD AND KMCK TO BEGIN THE TAF PERIOD WITH
CONDITIONS RAPIDLY DETERIORATING SOON. THE COLD FRONT IS ALREADY
MOVING INTO NORTHWEST KANSAS. NORTH WINDS BEHIND THE FRONT ARE
ALREADY GUSTING TO 40 KTS IN KAKO AND 42 KTS IN KLIC.
KGLD WILL BE GUSTING TO NEAR 42 KTS AROUND 08Z WITH SNOW. ALSO
INCLUDED BLOWING SNOW WITH VISIBILITY AT 1SM. A TEMPO GROUP WAS
INCLUDED FOR WHEN THE HEAVIEST BANDS OF SNOW ARE EXPECTED TO MOVE
ACROSS THE TERMINAL BETWEEN 08Z AND 11Z. VISIBILITY MAY BECOME
LIFR AT 1/2SM. SNOW SHOULD START TO TAPER OFF AROUND 12Z...THIS
TIME IS PUSHED BACK A LITTLE FROM THE 0Z TAFS SINCE RAP MODEL
UPDATES SHOW SNOW LINGERING OVER THE TERMINAL A LITTLE LONGER THAN
PREVIOUSLY THOUGHT. BY LATE MORNING...WIND GUSTS WILL RAMP UP
AGAIN TO NEAR 46 KTS AND THEN COME DOWN BY LATER AFTERNOON WITH
GUSTS DIMINISHING AROUND 0Z.
KMCK SHOULD GUST TO 35 KTS AROUND 07Z AS SHOWERS MOVE INTO THE
TERMINAL. NORTH WINDS WILL INCREASE AROUND 09Z WITH GUSTS NEAR 38
KTS AND LIGHT SNOW BEHIND THE FRONT. VISIBILITY SHOULD BE SIMILAR
TO KGLD WITH BLOWING SNOW SO HAVE IT REDUCED TO 1SM WITH A TEMPO
GROUP FOR LIFR VISIBILITY OF 1/2SM FROM 08Z TO 11Z. ALSO PUSHED
BACK ENDING TIME FOR SNOW TO 13Z. NORTHWEST WINDS WILL INCREASE
ONCE AGAIN IN THE EARLY AFTERNOON TO AROUND 40 KTS AND THEN WILL
DECREASE LATER IN THE AFTERNOON WITH GUSTS DIMINISHING AROUND 0Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY UNTIL 6 AM MST /7 AM CST/ EARLY THIS
MORNING FOR KSZ001-002-013-014-027-041.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ THIS MORNING TO 5 PM MST
/6 PM CST/ THIS AFTERNOON FOR KSZ001>004-013>016-027>029-
041-042.
WINTER WEATHER ADVISORY UNTIL 8 AM CST THIS MORNING FOR KSZ003-
004-015-016-028-029-042.
CO...WINTER WEATHER ADVISORY UNTIL 6 AM MST EARLY THIS MORNING FOR
COZ090>092.
WIND ADVISORY FROM 9 AM THIS MORNING TO 5 PM MST THIS AFTERNOON
FOR COZ090>092.
NE...WINTER WEATHER ADVISORY UNTIL 6 AM MST /7 AM CST/ EARLY THIS
MORNING FOR NEZ079>081.
WIND ADVISORY FROM 9 AM MST /10 AM CST/ THIS MORNING TO 5 PM MST
/6 PM CST/ THIS AFTERNOON FOR NEZ079>081.
&&
$$
SHORT TERM...LOCKHART
LONG TERM...024
AVIATION...ALW/RRH
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
521 AM CST Thu Feb 20 2014
.SHORT TERM...(Today and Tonight)
Issued at 430 AM CST THU FEB 20 2014
At the surface a very strong trough has formed on the eastern side
of the Rocky mountains, and currently sits over SC/SE Kansas. The
surface pressure gradient associated with this very strong trough
will cause southerly winds to pick up on the eastern edge to around
20 to 30 mph with gusts approaching 40 mph later today. An evident
surface warm front currently sits along Interstate 70, and is
characterized by temperatures in the 30s to lower 40s north of the
boundary to temperatures well in the 50s to lower 60s in the warm
sector south of the boundary. Thunderstorms are currently forming
along along the advancing warm front and will have plenty of
instability to grow upscale into strong thunderstorms. This activity
is generally forming along a strong low level jet which is currently
nosing into western Missouri, and is characterized by strong 850
winds between 50 and 60 kts. Effective bulk shear is between 40 and
50 kts, and given strong MU elevated CAPE of around 1000 J/kg the
ingredients are in place for these storms to be strong to marginally
severe. As the morning progresses HRRR indicates that these storms
will form a line spanning west to east just north of Interstate 70,
and will lift north through the day. Expect the bulk of the strong
thunderstorm potential to move northward into Iowa by around 10 am.
The focus then shifts to the late morning and afternoon hours, when
areas of far northwestern Missouri could experience a period of
moderate to heavy snow. The main mid level trough, which currently
sits over the High Plains will swing through the area later this
afternoon. Southern and Central Missouri will likely see a down tick
in precipitation coverage as the systems dry slot races through
southern and central Missouri. Across northern Missouri large scale
ascent associated with the mid level trough will bring another round
of precipitation later this morning. The aforementioned surface
trough will continue eastward, and behind the departing trough cold
northwest winds will crash into the area causing the thermal profile
to cool very quickly. By mid morning the thermal profile along
northern Missouri will be cooled adequately for snow production.
Very strong low/mid level frontogenesis in northern Missouri, as
well as some negative EPV will enhance the lift associated with the
mid level wave. All told there could be up to 15 to 20 -ubar of
Omega this morning and this afternoon contributing to rather
efficient snow production. While cold air will rush in surface
temperatures will struggle to drop below freezing, so any snow
production and accumulation may be mitigated by the warmer surface
temperatures. Went with a general 10-12:1 snow ratio to attain a
final figure of around 2 to 4 inches of snow accumulation for the
far NW corner of Missouri, with decreasing amounts toward the east
and south. Concurrent to the snow will be strong northwest winds,
which will race in as the surface pressure gradient behind the
departing trough moves through the area this afternoon. Expect the
winds to be sustained out of the northwest around 30 to 40 mph, with
gusts perhaps exceeding 50 mph. The strong winds and period of
moderate to heavy snow will cause visibility to decrease through the
day. Expect the period of snowfall to be rather brief as the overall
system quickly glides off to the northeast. By mid afternoon expect
the bulk of the precipitation to be off to the north, with perhaps
some lingering rain/snow through the evening.
Model soundings indicate that the low levels could stay well mixed
through the evening and into the overnight hours, which would allow
the strong wind gusts to continue at least into the evening and
perhaps into the overnight hours before gradually dissipating early
Friday morning.
.LONG TERM...(Friday through Wednesday)
Issued at 430 AM CST THU FEB 20 2014
A return to a West Coast blocking pattern, similar to what prevailed
through much of January, will send us back into a cold and dry
pattern by early next week. Primary cold front will drop into the
forecast area Friday night with a reinforcing shot of cold air
arriving Sunday. Temperatures in this pattern won`t be near as cold
as they were back in January, but still about 10 degrees below
average with highs in the 20s and 30s and lows in the teens and 20s
for much of next week. Could see some light snow Monday and Monday
night with a broad upper impulse tracking through the Upper Midwest
but better chances will be to our north.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday Morning)
Issued at 516 AM CST THU FEB 20 2014
Cluster of thunderstorms currently affecting KMCI and KSTJ will move
off to the north within the next couple hours. Not expecting much in
the way of convective redevelopment once these showers pass, however
there will be the chance for some light rain/snow mix later this
afternoon. The bigger story for this afternoon will be the very
strong winds, which will race into the area bringing 30 to 40 kt
gusts later this afternoon. Expect winds to gradually dissipate later
this evening, but winds will still be out of the northwest around 15
to 25 kts.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY from 10 AM this morning to 9 PM CST this evening
FOR KSZ025-057-060-102>105.
WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR KSZ025-
102.
MO...WIND ADVISORY from 10 AM this morning to 9 PM CST this evening
FOR MOZ001>005-011>014-020>022-028>031-037>040-043>046-053-
054.
WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR
MOZ001>005-011>013-020.
WIND ADVISORY from 1 PM this afternoon to Midnight CST tonight
FOR MOZ006>008-015>017-023>025-032-033.
FLOOD WATCH through this afternoon FOR MOZ006>008-015>017-
023>025.
&&
$$
SHORT TERM...Leighton
LONG TERM...Hawblitzel
AVIATION...Leighton
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
434 AM CST Thu Feb 20 2014
.SHORT TERM...(Today and Tonight)
Issued at 430 AM CST THU FEB 20 2014
At the surface a very strong trough has formed on the eastern side
of the Rocky mountains, and currently sits over SC/SE Kansas. The
surface pressure gradient associated with this very strong trough
will cause southerly winds to pick up on the eastern edge to around
20 to 30 mph with gusts approaching 40 mph later today. An evident
surface warm front currently sits along Interstate 70, and is
characterized by temperatures in the 30s to lower 40s north of the
boundary to temperatures well in the 50s to lower 60s in the warm
sector south of the boundary. Thunderstorms are currently forming
along along the advancing warm front and will have plenty of
instability to grow upscale into strong thunderstorms. This activity
is generally forming along a strong low level jet which is currently
nosing into western Missouri, and is characterized by strong 850
winds between 50 and 60 kts. Effective bulk shear is between 40 and
50 kts, and given strong MU elevated CAPE of around 1000 J/kg the
ingredients are in place for these storms to be strong to marginally
severe. As the morning progresses HRRR indicates that these storms
will form a line spanning west to east just north of Interstate 70,
and will lift north through the day. Expect the bulk of the strong
thunderstorm potential to move northward into Iowa by around 10 am.
The focus then shifts to the late morning and afternoon hours, when
areas of far northwestern Missouri could experience a period of
moderate to heavy snow. The main mid level trough, which currently
sits over the High Plains will swing through the area later this
afternoon. Southern and Central Missouri will likely see a down tick
in precipitation coverage as the systems dry slot races through
southern and central Missouri. Across northern Missouri large scale
ascent associated with the mid level trough will bring another round
of precipitation later this morning. The aforementioned surface
trough will continue eastward, and behind the departing trough cold
northwest winds will crash into the area causing the thermal profile
to cool very quickly. By mid morning the thermal profile along
northern Missouri will be cooled adequately for snow production.
Very strong low/mid level frontogenesis in northern Missouri, as
well as some negative EPV will enhance the lift associated with the
mid level wave. All told there could be up to 15 to 20 -ubar of
Omega this morning and this afternoon contributing to rather
efficient snow production. While cold air will rush in surface
temperatures will struggle to drop below freezing, so any snow
production and accumulation may be mitigated by the warmer surface
temperatures. Went with a general 10-12:1 snow ratio to attain a
final figure of around 2 to 4 inches of snow accumulation for the
far NW corner of Missouri, with decreasing amounts toward the east
and south. Concurrent to the snow will be strong northwest winds,
which will race in as the surface pressure gradient behind the
departing trough moves through the area this afternoon. Expect the
winds to be sustained out of the northwest around 30 to 40 mph, with
gusts perhaps exceeding 50 mph. The strong winds and period of
moderate to heavy snow will cause visibility to decrease through the
day. Expect the period of snowfall to be rather brief as the overall
system quickly glides off to the northeast. By mid afternoon expect
the bulk of the precipitation to be off to the north, with perhaps
some lingering rain/snow through the evening.
Model soundings indicate that the low levels could stay well mixed
through the evening and into the overnight hours, which would allow
the strong wind gusts to continue at least into the evening and
perhaps into the overnight hours before gradually dissipating early
Friday morning.
.LONG TERM...(Friday through Wednesday)
Issued at 430 AM CST THU FEB 20 2014
A return to a West Coast blocking pattern, similar to what prevailed
through much of January, will send us back into a cold and dry
pattern by early next week. Primary cold front will drop into the
forecast area Friday night with a reinforcing shot of cold air
arriving Sunday. Temperatures in this pattern won`t be near as cold
as they were back in January, but still about 10 degrees below
average with highs in the 20s and 30s and lows in the teens and 20s
for much of next week. Could see some light snow Monday and Monday
night with a broad upper impulse tracking through the Upper Midwest
but better chances will be to our north.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1130 PM CST WED FEB 19 2014
Scattered showers and occasional, isolated thunderstorms will
continue through the night across most of the region ahead of a
northeastward moving warm front. As the warm front approaches between
10z-12z Thursday, another round of more robust thunderstorms are
possible, especially along and north of Interstate 70. South of the
front, IFR to LIFR stratus and some light fog are expected to spread
into the TAF sites between 12z-16z. After 16z, a cold front will
sweep through the area from west to east, bringing strong northwest
winds, IFR to LIFR stratus, and scattered light showers, possibly
mixing with or changing over to snow in northwest and far northern
Missouri. Blowing snow with briefly reduced visibility is possible
across far northwest Missouri during the early afternoon hours, but
should stay north of all TAF sites.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY from 10 AM this morning to 9 PM CST this evening
FOR KSZ025-057-060-102>105.
WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR KSZ025-
102.
MO...WIND ADVISORY from 10 AM this morning to 9 PM CST this evening
FOR MOZ001>005-011>014-020>022-028>031-037>040-043>046-053-
054.
WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR
MOZ001>005-011>013-020.
WIND ADVISORY from 1 PM this afternoon to Midnight CST tonight
FOR MOZ006>008-015>017-023>025-032-033.
FLOOD WATCH through this afternoon FOR MOZ006>008-015>017-
023>025.
&&
$$
SHORT TERM...Leighton
LONG TERM...Hawblitzel
AVIATION...Laflin
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1045 AM EST THU FEB 20 2014
.SYNOPSIS...HIGH PRESSURE OVER THE MID ATLANTIC WILL MOVE OFFSHORE
TODAY. A WARM FRONT WILL MOVE NORTH THROUGH THE REGION LATE THIS
AFTERNOON. A STRONG COLD FRONT WILL SWEEP EAST ACROSS THE AREA
FRIDAY. HIGH PRESSURE WILL BUILD INTO THE REGION FOR THE FIRST PART
OF THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM THURSDAY...
REST OF TODAY: ONLY SMALL CHANGES NEEDED TO THE EXISTING FORECAST.
THE DEW POINT DISCONTINUITY IS VERY APPARENT WITH VALUES RANGING
FROM THE MID 30S IN THE FAR NORTH (WHERE SURFACE WINDS ARE MORE
EASTERLY OR ENE) TO LOWER 50S IN THE SOUTH (WITH MORE SOUTHEASTERLY
SURFACE WINDS). THIS WARM FRONTAL ZONE IS EXPECTED TO TRANSLATE
NORTHWARD TODAY... ALBEIT WITH LITTLE FANFARE AS INCOMING PRECIP
WATER (ACCORDING TO BLENDED TPW IMAGERY) REMAINS BELOW ONE INCH WITH
CONSIDERABLE DRY AIR THROUGH THE COLUMN (ACCORDING TO UPSTREAM
SOUNDINGS AND RAP FORECAST SOUNDINGS) AND AN ABSENCE OF FORCING FOR
ASCENT. CONVECTION-ALLOWING MODELS PICK UP ON THE PATCHY SPRINKLES
IN THE FAR NW CWA BUT THESE ARE EXPECTED TO DRY UP AND HEAD TO OUR
NORTH IN THE NEXT COUPLE OF HOURS... RESULTING IN A POP-FREE
AFTERNOON AREAWIDE. THE LATEST TEMP TRENDS... AS WELL AS THE
LINGERING LOWER CLOUDS IN THE NW CWA AND PLENTY OF FILTERED SUNSHINE
ELSEWHERE... SUPPORT HIGHS FROM 65 NW RANGING TO 76 SOUTHEAST.
(TODAY`S RECORD HIGH IS 75 AT RDU IN 1939... 74 IN GSO IN 1922...
AND 79 IN FAY IN 1956.) -GIH
TONIGHT...LOW LEVEL JET INCREASES IN RESPONSE TO THE APPROACH OF A
SIGNIFICANT S/W CROSSING THE UPPER MID WEST INTO THE GREAT LAKES.
WHILE SHOULD SEE SFC WINDS INCREASE TO AROUND 15 MPH AFTER
MIDNIGHT...DO NOT THINK THAT WE WILL BE ABLE TO TAP INTO THE
STRONGER WINDS JUST OFF THE SURFACE DUE TO A SFC BASED STABLE LAYER.
THE WELL MIXED AIR MASS ALONG WITH THE OVERCAST STRATUS DECK WILL
LEAD TO A MILD OVERNIGHT WITH TEMPS EITHER HOLDING STEADY OR SLOWLY
RISING. ANY SHOWERS THAT OCCUR SHOULD BE ISOLATED AND MAINLY
CONFINED TO THE YADKIN RIVER VALLEY. SHOULD SEE AN INCREASE IN
SHOWER COVERAGE HOWEVER TOWARD DAYBREAK IN THE FAR NW PIEDMONT AS A
STRONG COLD FRONT ASSOCIATED WITH THE GREAT LAKES S/W APPROACHES.
MIN TEMPS UPPER 50S TO AROUND 60. -WSS
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 315 AM THURSDAY...
FRIDAY...SFC COLD FRONT PROJECTED TO MARCH EAST ACROSS CENTRAL NC
DURING THE MORNING THROUGH THE EARLY AFTERNOON HOURS. CONVERGENCE
ALONG THE BOUNDARY ALONG WITH A MOIST AIR MASS SHOULD RESULT IN A
BAND OF HEAVY SHOWERS. WILL SEE POTENTIAL FOR STRONG GUSTY SFC WINDS
TO OCCUR AHEAD OF THE BOUNDARY (NEAR 30KTS). EXPECT MAIN BAND OF
SHOWERS TO LIE ALONG THE U.S. 1 CORRIDOR BY LATE MORNING/MIND
DAY...AND INTO THE COASTAL PLAIN BY EARLY AFTERNOON. CONVECTIVE
PARAMETERS SUGGEST A HIGH SHEAR/LOW CAPE ENVIRONMENT WILL EXISTS
ALONG AND EAST OF HIGHWAY 1. THIS WILL LEAD TO THE DEVELOPMENT OF A
FEW THUNDERSTORMS IN THE LINE OF HEAVY SHOWERS. THIS MAY LEAD TO AN
INCREASE THREAT FOR DAMAGING WIND GUSTS AS THE SHOWERS AND STORMS
PROGRESS EAST INTO THE COASTAL PLAIN AND INTERACT WITH THE LOW LEVEL
JET. LOW LEVEL HELICITY VALUES SUPPORTIVE OF SOME WEAK ROTATION BUT
THE LACK OF A WELL-DEFINED SFC CIRCULATION IN OUR VICINITY WILL
LIMIT TORNADIC THREAT.
MAIN MID-UPPER LEVEL SUPPORT SWEEPS THROUGH THE COASTAL PLAIN BY MID
AFTERNOON...LEADING TO RAPID DISSIPATION/EXIT OF THE SHOWERS AND
STORMS. DOWNSLOPE FLOW IN THE WAKE OF THE SFC BOUNDARY COUPLED WITH
DECENT SUBSIDENCE IN THE WAKE OF THE MID-UPPER LEVEL TROUGH WILL
LEAD TO CLEARING SKIES IN THE WESTERN PIEDMONT BY EARLY
AFTERNOON...AND INTO THE TRIANGLE AREA AND NORTHEAST PIEDMONT BY MID-
LATE AFTERNOON.
MAX TEMPS FRIDAY DEPENDENT ON ARRIVAL TIME OF SHOWERS AND POSSIBLY
CLEARING IN THE AFTERNOON. MODEL GUIDANCE IN REASONABLE AGREEMENT
AND GENERALLY FOLLOWED. MAX TEMPS MID 60S NW TO LOWER 70S FAR EAST.
COOLER DRIER AIR WILL OVERSPREAD CENTRAL NC FRIDAY NIGHT AS HIGH
PRESSURE OVER THE LOWER MS VALLEY BUILDS EAST-NE. SFC WINDS WILL
SUBSIDE AND UNDER MAINLY CLEAR SKIES...SHOULD SEE TEMPS COOL BACK
INTO THE 30S BY EARLY SATURDAY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 306 AM THURSDAY...
WITH THE FRONT OFFSHORE... HIGH PRESSURE WILL BRIEFLY BUILD ACROSS
THE AREA SATURDAY. A SIGNIFICANTLY DRIER AIRMASS ACROSS THE AREA
WILL BRING MOSTLY SUNNY SKIES. ON SUNDAY... WITH BROAD HIGH PRESSURE
OVER THE ATLANTIC AND A COLD FRONT APPROACHING FROM THE WEST... LOW
LEVEL SOUTHWEST FLOW WILL ENCOMPASS THE AREA... AND LOW LEVEL
THICKNESSES WILL RISE A OVER SATURDAY... PROVIDING SLIGHTLY WARMER
TEMPERATURES.
BROAD TROUGHING WILL BEGIN TO RE-ESTABLISH ITSELF ACROSS THE EAST
COAST TO BEGIN THE WEEK. A DRY COLD FRONT WILL MOVE THROUGH THE AREA
EARLY MONDAY... AND TEMPERATURES WILL FALL BACK A FEW DEGREES BELOW
NORMAL THROUGH THE FIRST PART OF THE WEEK. ANOTHER COLD FRONT LOOKS
LIKELY TO CROSS THE AREA WEDNESDAY... DROPPING TEMPERATURES AGAIN BY
A FEW DEGREES. GLOBAL MODELS DEVELOP A SURFACE WAVE ALONG THE
BAROCLINIC ZONE NEAR THE COAST. WILL CONTINUE WITH SLIGHT CHANCE
POPS THE LATTER HALF OF TUESDAY INTO EARLY WEDNESDAY.
&&
.AVIATION /12Z WEDNESDAY THROUGH MONDAY/...
AS OF 708 AM THURSDAY...
ASIDE FROM POCKETS OF MVFR VISIBILITY DUE TO FOG...VFR CONDITIONS
COVER CENTRAL NC EARLY THIS MORNING. STILL A CHANCE THAT LOW STRATUS
WILL DEVELOP AROUND 14Z AND PERSIST UNTIL 18Z WITH IFR/LOW END MVFR
CEILINGS. IF STRATUS DOES NOT DEVELOP...VFR CONDITIONS WILL PERSIST
THROUGH THE AFTERNOON THROUGH THE EARLY EVENING HOURS. SOUTHEASTERLY
SFC WINDS WILL BECOME A LITTLE BREEZY....OCCASIONALLY GUSTING BETWEEN
16 AND 20 KTS.
LOW CLOUDS WILL RETURN LATE TONIGHT (AFTER 06Z FRIDAY) AS SLY FLOW
AHEAD OF A STRONG COLD FRONT PULLS WARM MOIST AIR INTO CENTRAL NC.
EXPECT WIDESPREAD IFR/LIFR CEILINGS LATE TONIGHT INTO EARLY FRIDAY
MORNING. THE APPROACHING COLD FRONT WILL INCREASE THE THREAT FOR
SHOWERS IN THE KINT AND KGSO VICINITIES BETWEEN 09Z-12Z FRIDAY.
THE COLD FRONT WILL PROGRESS EAST ACROSS THE PIEDMONT FRIDAY MORNING
AND THE SANDHILLS AND COASTAL PLAIN IN THE EARLY AFTERNOON.
WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS WILL ACCOMPANY THE FRONT.
A FEW THUNDERSTORM WIND GUST MAY REACH AS HIGH AS 40-50KTS...MAINLY
IN VICINITY OF KRDU...KFAY AND KRWI. IN ADDITION...EXPECT IFR/MVFR
CEILINGS.
AVIATION WEATHER CONDITIONS WILL IMPROVE WEST-TO-EAST AS WESTERLY
WINDS BEHIND THE DEPARTING ADVECT DRIER MORE STABLE AIR INTO CENTRAL
NC. EXPECT VFR CONDITIONS IN THE WESTERN PIEDMONT BY MID
AFTERNOON...AND INTO THE COASTAL PLAIN AND SANDHILLS BY EARLY
EVENING. WITH HIGH PRESSURE IN CONTROL OF OUR WEATHER THIS
WEEKEND...EXPECT VFR CONDITIONS THROUGH SUNDAY. SLY FLOW ON THE BACK
SIDE OF THE RETREATING HIGH PRESSURE SYSTEM WILL LIKELY INCREASE THE
THREAT FOR SUB VFR CONDITIONS SUNDAY NIGHT INTO MONDAY MORNING.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JB
NEAR TERM...HARTFIELD/WSS
SHORT TERM..WSS
LONG TERM...SEC
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
937 AM EST THU FEB 20 2014
.SYNOPSIS...
WARM FRONT LIFTS NORTH TODAY. STRONG COLD FRONT TONIGHT. ANOTHER
SYSTEM MOVES THROUGH ON SUNDAY. SNOW MONDAY NIGHT INTO TUESDAY.
WINTER CONTINUES IN NEW WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAD TO ADJUST THE POPS WITH THE ONGOING CONVECTION. STILL PLAYING
THE THUNDER CARD ALTHOUGH IT APPEARS THE CELLS ARE TRANSFORMING
INTO LARGER AREA OF SHOWERS. SHOULD EXIT TO THE NORTH BY 17Z.
PREVIOUS DISCUSSION...
A WARM FRONT LIFTS NORTH THIS MORNING WITH BETTER CHANCES FOR RAIN
SHOWERS ACROSS SOUTHEAST OH...NORTHEAST KY...AND PORTIONS OF WV
ALONG THE OH RIVER. INCREASED POPS LIFTING WITH THE WARM FRONT TO
LIKELY...DIMINISHING AS SHOWERS MOVE NORTH.
MODELS INDICATE WIND FLOW WILL INCREASE FROM THE SOUTHWEST TO
60-70 KNOTS AT H85 AHEAD OF A COLD FRONT EXPECTED TO PASS TONIGHT.
SOME OF THESE STRONG WINDS WILL MOST LIKELY BE FELT OVER THE
HIGHER TERRAIN...AND ALONG SHOWERS WHICH WILL BE CAPABLE TO MIX
DOWN THESE WINDS. HOWEVER...IN THE WARM SECTOR IT WILL STRUGGLE
TO MIX DOWN PER UP GLIDING ASPECT EVIDENT IN ISENTROPIC SURFACES.
THE FRONT SHOULD PRODUCE A QUICK 0.5 INCHES OF RAIN...PERHAPS MORE
ALONG THE STRONGER STORM OR SHOWER.
HOLD OFF ON ISSUING A WIND ADVISORY AS THE EVENT LOOKS MARGINAL
ATTM. THE BEST WINDS 40 TO 50 KNOTS...OCCUR IN THE WARM SECTOR AS
EXPLAINED BEFORE. A WIND ADVISORY COULD BE NECESSARY ALONG OR
BEHIND THE FRONT. OR THE EVENT COULD BE TREATED WITH SPS AND
SEVERE STORM WARNINGS IF NEEDED. WILL LET DAY SHIFT TO DECIDE HOW
TO HANDLE THIS EVENT.
THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS TONIGHT WITH
DAMAGING WINDS BEING THE MAIN THREAT. SMALL HAIL CAN NOT BE RULED
OUT OF THE QUESTIONS AS FREEZING LEVELS WILL BE AROUND 9-10 KFT.
SNOW MELT HAVE CAUSE WATERS IN SMALL STREAMS TO RISE. FLOODING WAS
KEPT IN THE HAZARDOUS WEATHER OUTLOOK.
MINOR TWEAKS TO PREVIOUS TEMPERATURES. BLENDED THE RUC13 WITH MOST
GUIDANCE FOR TEMPERATURES THROUGH THE PERIOD.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
STRONG SYSTEM EXITING THE AREA AT THE OUTSET OF THE SHORT-TERM
PERIOD 12Z FRI. CONSENSUS OF NWP OUTPUT SLOWING THE FRONT JUST A BIT
OVERNIGHT FROM PREV RUNS...WITH THE VARIOUS MODELS HAVING THE SFC FRONT
LOCATED PRETTY MUCH ON OUR EASTERN CWA BORDER OF POCAHONTAS AND
RANDOLPH COUNTIES AT 12Z FRI. ELEVATED FRONT OF COURSE THEN IS A BIT
SLOWER AS WELL AND CROSSES THE HIGH PEAKS BTWN 12Z-15Z FRI MORNING
WITH A RAPID COOL DOWN FOR LOCATIONS SUCH AS SNO FROM THE LOW 40S AT
12Z FRI TO THE UPPER 20S/LOW 30S BY 15Z FRI. REFLECTED THIS IN THE
HOURLY TEMP TRACE FRIDAY MORNING. ALSO SLOWED DOWN PRECIP EXIT JUST
A BIT WITH IT...WITH LATEST NAM12 AND GFS BUFKIT SOUNDINGS STILL
INDICATING NEARLY COMPLETE SATURATION UP TO 600-500MB AT 15Z FRI.
THIS PRECIP WILL BE ALL RAIN INITIALLY ON THE HIGHEST PEAKS BUT WILL
QUICKLY CHANGE TO SNOW FOR A BRIEF WINDOW OF 1-3 HOURS AS THE PRECIP
MOVES OUT OF THE AREA. MAY GET A QUICK HALF-INCH TO PERHAPS AN INCH
OF SNOW FRI MID-MORNING AS THIS SYSTEM WINDS DOWN...BUT AGAIN THIS
SHOULD BE CONFINED TO ELEVATIONS MAINLY ABOVE 3KFT.
ONCE THE LAST OF THE PRECIP MOVES OUT...THE REMAINDER OF FRIDAY WILL
SEE IMPROVING CONDITIONS WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES BY
THE AFTERNOON HOURS WITH TEMPS INTO THE UPPER 40S TO LOWER 50S FOR
THE LOWLANDS. MAY SEE A BIT MORE STRATO-CU HANGING ON ACROSS THE
NORTHERN ZONES DURING THE AFTERNOON HOURS WITH A BIT MORE LLVL
MOISTURE TO WORK WITH. IT WILL CONTINUE TO BE A VERY WINDY DAY
ACROSS THE AREA WITH STRONG SFC LOW PRESSURE LOCATED OVER THE
NORTHERN GREAT LAKES. FOR THE LOWLANDS...EXPECT GENERAL 20G30KTS FOR
MUCH OF THE DAY...WHILE THE HIGHEST PEAKS OF THE EASTERN MOUNTAINS
SEE POTENTIALLY 40-45KT GUSTS. A 50KT GUST WOULD NOT BE IMPOSSIBLE
TO REALIZE AT THE HIGHEST ELEVATIONS...PARTICULARLY FOR AN HOUR OR
SO IMMEDIATELY FOLLOWING THE FRONTAL PASSAGE.
FRIDAY EVENING THE SFC LOW OVER THE GREAT LAKES CONTINUES TO SLOWLY
PULL AWAY WITH SFC HIGH PRESSURE LOCATED NEAR THE SMOKY MOUNTAIN
REGION BY 12Z SAT. DRY WEATHER WILL CONTINUE AND THE WORST OF THE
WINDY CONDITIONS WILL QUICKLY DISSIPATE NEAR AND AFTER SUNSET WITH
THE LOSS OF ANY MIXING. WITH A DECENT PRESSURE GRADIENT OVER THE
AREA WILL STILL MAINTAIN A PUFF OF WIND IT APPEARS. ALSO WILL SEE
SOME WARM ADVECTION MAKING INTO THE AREA BY AND AFTER 06Z SAT.
INHERITED MIN TEMPS FROM PREV SHIFT GENERALLY LOOK GOOD...WITH MINOR
ADJUSTMENTS.
SATURDAY WILL BE ANOTHER PLEASANT DAY. SFC HIGH PRESSURE SLOWLY
PULLS EAST WITH A RETURN S/SW FLOW SETTING UP BY THE AFTERNOON.
BUMPED UP MAX TEMPS FOR SATURDAY A GOOD 3-5 DEGREES AREA-WIDE WITH
925MB TEMPS PROGGED AROUND 8-9C...EXPECT TEMPS TO REBOUND INTO THE
MID 50S NORTHERN LOWLANDS AND UPPER 50S TO 60 CENTRAL AND SOUTHERN
LOWLANDS. IT WILL STILL BE ON THE BREEZY SIDE BUT NOT NEARLY AS
GUSTY AS FRIDAY...SO IT WILL PROBABLY FEEL MUCH NICER THAN FRIDAY.
SATURDAY NIGHT...INHERITED MINS THE LOW/MID 30S LOWLANDS STILL
APPEAR ON TRACK AGAIN...WITH JUST A FEW ADJUSTMENTS. A WEAK
DISTURBANCE IN THE NEAR ZONAL FLOW MAY DRAG A WEAK COLD FRONT INTO
THE NORTHERN ZONES BY END OF PERIOD AND THUS WILL CONTINUE THE
SLIGHT TO LOW CHANCE POPS FROM PREV SHIFT IN THESE AREAS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
MODELS SHOWING A WEAK SYSTEM SYSTEM MOVING THROUGH SATURDAY NIGHT
INTO SUNDAY. TYPE OF PRECIPITATION IS QUESTIONABLE BASED ON TIMING
AND HOW MUCH RADIATION OCCURS SATURDAY NIGHT IN ADVANCE OF THE
SYSTEM. USED A BLEND OF THE ECMWF AND GFS.
FOR MONDAY THROUGH WEDNESDAY...USED A BLEND OF THE GEFS ENSEMBLE
MEAN AND ECMWF ENSEMBLE MEAN. THIS KEEPS A TROUGH OVER THE EASTERN
UNITED STATES CREATING A WINTER WEATHER SITUATION WHERE VARIOUS
WAVES COULD CREATE SNOW AT TIMES. THE TIMING OF THE WAVES AND
INTENSITY OF THE COLD AIR REMAIN IN QUESTION HOWEVER...AS VARIOUS
ENSEMBLE MEMBERS VARY CONSIDERABLY.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS WILL CONTINUE AT MOST SITES...EXCEPT MVFR UNDER
LIGHT FOG AT PKB AND VICINITY.
CALM WINDS WILL GRADUALLY INCREASE FROM THE SOUTHEAST AT THE
SURFACE AND SOUTHWEST ALOFT BY MID MORNING...LASTING INTO THE
EVENING HOURS.
CEILINGS WILL REMAIN AT LEAST MVFR FOR THE MOST PART AFTER FROPA
EXCEPT IFR ALONG THE EASTERN MOUNTAINS BY FRIDAY 12Z.
LOW LEVEL WIND SHEAR WILL BE POSSIBLE LATER THIS AFTERNOON AND
TONIGHT IF LOWER ATMOSPHERE DECOUPLES. WINDS ALOFT WILL INCREASE
EVEN THIS EVENING FOR FEW HOURS UNTIL DIURNAL MIXING STOPS. MODELS
SHOW H85 WINDS INCREASING TO 50 KNOTS BY 18Z TODAY...AND EVEN 70
KNOTS BY 06Z TONIGHT...AHEAD OF THE FRONT.
EXPECT SOME CONVECTION DEVELOPING AHEAD OF THE COLD FRONT THIS
AFTERNOON AND EVENING...WITH THE MAIN CONVECTIVE SQUALL LINE WITH
FAST MOVING SHOWERS/EMBEDDED THUNDERSTORM REACHING SOUTHEAST OHIO
AROUND MIDNIGHT.
CONVECTION AHEAD OF FROPA SHOULD REACH SOUTHEAST OH BY 06-09Z
FRIDAY TO SPREAD IFR CEILINGS ALONG THEIR PATH.
THERE IS A SLIGHT RISK FOR DAMAGING WINDS WITH STORMS WITH THIS
FROPA. THE WINDY SHOWERS OR STORMS WILL SPREAD QUICKLY EAST. THIS
WILL BE AN HIGH SHEAR...LOW CAPE ENVIRONMENT...WITH PW AROUND 1
INCH.
HAVE CLOUDS THICKENING FROM 12 TO 18Z TODAY FROM SOUTH TO NORTH
DOWN TO 3500 FEET...EXCEPT 2500 FEET EXTREME NORTHWEST PORTIONS OF
OUR CWA. CEILINGS DETERIORATE WITH THE PROXIMITY OF FROPA
OVERNIGHT TONIGHT DOWN TO AROUND 2000 FEET UNDER RAIN SHOWERS.
BRIEF PERIODS OF IFR POSSIBLE ALONG HEAVIEST SHOWERS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MORE SHOWER COVERAGE ASSOCIATED WITH THE WARM
FRONT A BIT FURTHER EAST THAN FORECAST. TIMING COVERAGE OF LOWER
CLOUDS DEVELOPING ON EASTERN SLOPES 18Z THURSDAY TO 00Z FRIDAY
COULD VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
CRW CONSISTENCY M H H H H H H H H H H H
HTS CONSISTENCY M H H M M H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H M M M H H H H H L L
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z FRIDAY...
IFR POSSIBLE TONIGHT IN FAST MOVING AND GUSTY SHOWERS...AND
POSSIBLY BRIEF THUNDERSTORMS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/50
NEAR TERM...ARJ/26
SHORT TERM...50
LONG TERM...RPY
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
537 AM EST THU FEB 20 2014
.SYNOPSIS...
WARM FRONT LIFTS NORTH TODAY. STRONG COLD FRONT TONIGHT. ANOTHER
SYSTEM MOVES THROUGH ON SUNDAY. SNOW MONDAY NIGHT INTO TUESDAY.
WINTER CONTINUES IN NEW WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A WARM FRONT LIFTS NORTH THIS MORNING WITH BETTER CHANCES FOR RAIN
SHOWERS ACROSS SOUTHEAST OH...NORTHEAST KY...AND PORTIONS OF WV
ALONG THE OH RIVER. INCREASED POPS LIFTING WITH THE WARM FRONT TO
LIKELY...DIMINISHING AS SHOWERS MOVE NORTH.
MODELS INDICATE WIND FLOW WILL INCREASE FROM THE SOUTHWEST TO
60-70 KNOTS AT H85 AHEAD OF A COLD FRONT EXPECTED TO PASS TONIGHT.
SOME OF THESE STRONG WINDS WILL MOST LIKELY BE FELT OVER THE
HIGHER TERRAIN...AND ALONG SHOWERS WHICH WILL BE CAPABLE TO MIX
DOWN THESE WINDS. HOWEVER...IN THE WARM SECTOR IT WILL STRUGGLE
TO MIX DOWN PER UP GLIDING ASPECT EVIDENT IN ISENTROPIC SURFACES.
THE FRONT SHOULD PRODUCE A QUICK 0.5 INCHES OF RAIN...PERHAPS MORE
ALONG THE STRONGER STORM OR SHOWER.
HOLD OFF ON ISSUING A WIND ADVISORY AS THE EVENT LOOKS MARGINAL
ATTM. THE BEST WINDS 40 TO 50 KNOTS...OCCUR IN THE WARM SECTOR AS
EXPLAINED BEFORE. A WIND ADVISORY COULD BE NECESSARY ALONG OR
BEHIND THE FRONT. OR THE EVENT COULD BE TREATED WITH SPS AND
SEVERE STORM WARNINGS IF NEEDED. WILL LET DAY SHIFT TO DECIDE HOW
TO HANDLE THIS EVENT.
THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS TONIGHT WITH
DAMAGING WINDS BEING THE MAIN THREAT. SMALL HAIL CAN NOT BE RULED
OUT OF THE QUESTIONS AS FREEZING LEVELS WILL BE AROUND 9-10 KFT.
SNOW MELT HAVE CAUSE WATERS IN SMALL STREAMS TO RISE. FLOODING WAS
KEPT IN THE HAZARDOUS WEATHER OUTLOOK.
MINOR TWEAKS TO PREVIOUS TEMPERATURES. BLENDED THE RUC13 WITH MOST
GUIDANCE FOR TEMPERATURES THROUGH THE PERIOD.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
STRONG SYSTEM EXITING THE AREA AT THE OUTSET OF THE SHORT-TERM
PERIOD 12Z FRI. CONSENSUS OF NWP OUTPUT SLOWING THE FRONT JUST A BIT
OVERNIGHT FROM PREV RUNS...WITH THE VARIOUS MODELS HAVING THE SFC FRONT
LOCATED PRETTY MUCH ON OUR EASTERN CWA BORDER OF POCAHONTAS AND
RANDOLPH COUNTIES AT 12Z FRI. ELEVATED FRONT OF COURSE THEN IS A BIT
SLOWER AS WELL AND CROSSES THE HIGH PEAKS BTWN 12Z-15Z FRI MORNING
WITH A RAPID COOL DOWN FOR LOCATIONS SUCH AS SNO FROM THE LOW 40S AT
12Z FRI TO THE UPPER 20S/LOW 30S BY 15Z FRI. REFLECTED THIS IN THE
HOURLY TEMP TRACE FRIDAY MORNING. ALSO SLOWED DOWN PRECIP EXIT JUST
A BIT WITH IT...WITH LATEST NAM12 AND GFS BUFKIT SOUNDINGS STILL
INDICATING NEARLY COMPLETE SATURATION UP TO 600-500MB AT 15Z FRI.
THIS PRECIP WILL BE ALL RAIN INITIALLY ON THE HIGHEST PEAKS BUT WILL
QUICKLY CHANGE TO SNOW FOR A BRIEF WINDOW OF 1-3 HOURS AS THE PRECIP
MOVES OUT OF THE AREA. MAY GET A QUICK HALF-INCH TO PERHAPS AN INCH
OF SNOW FRI MID-MORNING AS THIS SYSTEM WINDS DOWN...BUT AGAIN THIS
SHOULD BE CONFINED TO ELEVATIONS MAINLY ABOVE 3KFT.
ONCE THE LAST OF THE PRECIP MOVES OUT...THE REMAINDER OF FRIDAY WILL
SEE IMPROVING CONDITIONS WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES BY
THE AFTERNOON HOURS WITH TEMPS INTO THE UPPER 40S TO LOWER 50S FOR
THE LOWLANDS. MAY SEE A BIT MORE STRATO-CU HANGING ON ACROSS THE
NORTHERN ZONES DURING THE AFTERNOON HOURS WITH A BIT MORE LLVL
MOISTURE TO WORK WITH. IT WILL CONTINUE TO BE A VERY WINDY DAY
ACROSS THE AREA WITH STRONG SFC LOW PRESSURE LOCATED OVER THE
NORTHERN GREAT LAKES. FOR THE LOWLANDS...EXPECT GENERAL 20G30KTS FOR
MUCH OF THE DAY...WHILE THE HIGHEST PEAKS OF THE EASTERN MOUNTAINS
SEE POTENTIALLY 40-45KT GUSTS. A 50KT GUST WOULD NOT BE IMPOSSIBLE
TO REALIZE AT THE HIGHEST ELEVATIONS...PARTICULARLY FOR AN HOUR OR
SO IMMEDIATELY FOLLOWING THE FRONTAL PASSAGE.
FRIDAY EVENING THE SFC LOW OVER THE GREAT LAKES CONTINUES TO SLOWLY
PULL AWAY WITH SFC HIGH PRESSURE LOCATED NEAR THE SMOKY MOUNTAIN
REGION BY 12Z SAT. DRY WEATHER WILL CONTINUE AND THE WORST OF THE
WINDY CONDITIONS WILL QUICKLY DISSIPATE NEAR AND AFTER SUNSET WITH
THE LOSS OF ANY MIXING. WITH A DECENT PRESSURE GRADIENT OVER THE
AREA WILL STILL MAINTAIN A PUFF OF WIND IT APPEARS. ALSO WILL SEE
SOME WARM ADVECTION MAKING INTO THE AREA BY AND AFTER 06Z SAT.
INHERITED MIN TEMPS FROM PREV SHIFT GENERALLY LOOK GOOD...WITH MINOR
ADJUSTMENTS.
SATURDAY WILL BE ANOTHER PLEASANT DAY. SFC HIGH PRESSURE SLOWLY
PULLS EAST WITH A RETURN S/SW FLOW SETTING UP BY THE AFTERNOON.
BUMPED UP MAX TEMPS FOR SATURDAY A GOOD 3-5 DEGREES AREA-WIDE WITH
925MB TEMPS PROGGED AROUND 8-9C...EXPECT TEMPS TO REBOUND INTO THE
MID 50S NORTHERN LOWLANDS AND UPPER 50S TO 60 CENTRAL AND SOUTHERN
LOWLANDS. IT WILL STILL BE ON THE BREEZY SIDE BUT NOT NEARLY AS
GUSTY AS FRIDAY...SO IT WILL PROBABLY FEEL MUCH NICER THAN FRIDAY.
SATURDAY NIGHT...INHERITED MINS THE LOW/MID 30S LOWLANDS STILL
APPEAR ON TRACK AGAIN...WITH JUST A FEW ADJUSTMENTS. A WEAK
DISTURBANCE IN THE NEAR ZONAL FLOW MAY DRAG A WEAK COLD FRONT INTO
THE NORTHERN ZONES BY END OF PERIOD AND THUS WILL CONTINUE THE
SLIGHT TO LOW CHANCE POPS FROM PREV SHIFT IN THESE AREAS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
MODELS SHOWING A WEAK SYSTEM SYSTEM MOVING THROUGH SATURDAY NIGHT
INTO SUNDAY. TYPE OF PRECIPITATION IS QUESTIONABLE BASED ON TIMING
AND HOW MUCH RADIATION OCCURS SATURDAY NIGHT IN ADVANCE OF THE
SYSTEM. USED A BLEND OF THE ECMWF AND GFS.
FOR MONDAY THROUGH WEDNESDAY...USED A BLEND OF THE GEFS ENSEMBLE
MEAN AND ECMWF ENSEMBLE MEAN. THIS KEEPS A TROUGH OVER THE EASTERN
UNITED STATES CREATING A WINTER WEATHER SITUATION WHERE VARIOUS
WAVES COULD CREATE SNOW AT TIMES. THE TIMING OF THE WAVES AND
INTENSITY OF THE COLD AIR REMAIN IN QUESTION HOWEVER...AS VARIOUS
ENSEMBLE MEMBERS VARY CONSIDERABLY.
&&
.AVIATION /10Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS WILL CONTINUE AT MOST SITES...EXCEPT MVFR UNDER
LIGHT FOG AT PKB AND VICINITY.
CALM WINDS WILL GRADUALLY INCREASE FROM THE SOUTHEAST AT THE
SURFACE AND SOUTHWEST ALOFT BY MID MORNING...LASTING INTO THE
EVENING HOURS.
CEILINGS WILL REMAIN AT LEAST MVFR FOR THE MOST PART AFTER FROPA
EXCEPT IFR ALONG THE EASTERN MOUNTAINS BY FRIDAY 12Z.
LOW LEVEL WIND SHEAR WILL BE POSSIBLE LATER THIS AFTERNOON AND
TONIGHT IF LOWER ATMOSPHERE DECOUPLES. WINDS ALOFT WILL INCREASE
EVEN THIS EVENING FOR FEW HOURS UNTIL DIURNAL MIXING STOPS. MODELS
SHOW H85 WINDS INCREASING TO 50 KNOTS BY 18Z TODAY...AND EVEN 70
KNOTS BY 06Z TONIGHT...AHEAD OF THE FRONT.
EXPECT SOME CONVECTION DEVELOPING AHEAD OF THE COLD FRONT THIS
AFTERNOON AND EVENING...WITH THE MAIN CONVECTIVE SQUALL LINE WITH
FAST MOVING SHOWERS/EMBEDDED THUNDERSTORM REACHING SOUTHEAST OHIO
AROUND MIDNIGHT.
CONVECTION AHEAD OF FROPA SHOULD REACH SOUTHEAST OH BY 06-09Z
FRIDAY TO SPREAD IFR CEILINGS ALONG THEIR PATH.
THERE IS A SLIGHT RISK FOR DAMAGING WINDS WITH STORMS WITH THIS
FROPA. THE WINDY SHOWERS OR STORMS WILL SPREAD QUICKLY EAST. THIS
WILL BE AN HIGH SHEAR...LOW CAPE ENVIRONMENT...WITH PW AROUND 1
INCH.
HAVE CLOUDS THICKENING FROM 12 TO 18Z TODAY FROM SOUTH TO NORTH
DOWN TO 3500 FEET...EXCEPT 2500 FEET EXTREME NORTHWEST PORTIONS OF
OUR CWA. CEILINGS DETERIORATE WITH THE PROXIMITY OF FROPA
OVERNIGHT TONIGHT DOWN TO AROUND 2000 FEET UNDER RAIN SHOWERS.
BRIEF PERIODS OF IFR POSSIBLE ALONG HEAVIEST SHOWERS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MORE SHOWER COVERAGE ASSOCIATED WITH THE WARM
FRONT A BIT FURTHER EAST THAN FORECAST. TIMING COVERAGE OF LOWER
CLOUDS DEVELOPING ON EASTERN SLOPES 18Z THURSDAY TO 00Z FRIDAY
COULD VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE THU 02/20/14
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EST 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H M M H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY L L L H H H H H M M M H
CKB CONSISTENCY L H H H H H H H H H H H
AFTER 12Z FRIDAY...
IFR POSSIBLE TONIGHT IN FAST MOVING AND GUSTY SHOWERS...AND
POSSIBLY BRIEF THUNDERSTORMS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/50
NEAR TERM...ARJ
SHORT TERM...50
LONG TERM...RPY
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS NORMAN OK
547 AM CST THU FEB 20 2014
.AVIATION...20 FEB 12Z TAF ISSUANCE...
MAJOR AVIATION CONCERN IS FOCUSED ON EXCESSIVE WINDS THIS MORNING
THROUGH THE EARLY AFTERNOON. CURRENTLY... WINDS ACROSS THE
PANHANDLES INTO SWRN KS ARE SUSTAINED 30 TO 40... GUSTING 45 TO
50 KTS. THESE STOUT WINDS WILL MOVE INTO NWRN OK THROUGH
SUNRISE... SPREADING E/SE ACROSS THE REGION THROUGH THE DAY AS THE
COLD FRONT CONTINUES ITS SURGE. WITH STRONG WINDS... BLOWING DIRT
WILL CAUSE VISIBILITY ISSUES AT AIRFIELDS ACROSS WRN AND CENTRAL
OKLAHOMA. EXPECT AIRFIELDS ACROSS WRN OK AND CENTRAL OK TO FLIRT
WITH MVFR VISIBILITIES THROUGH THE MORNING OFF AND ON DUE TO THE
BLOWING DIRT. LOW TO MID LEVEL STRATUS WILL CONTINUE TO STREAM TO
THE E/NE THIS MORNING... WITH ANY REMAINING MVFR CIGS ACROSS WRN
OK IMPROVING THROUGH THE MORNING AS THE FRONT MOVES IN. WINDS WILL
CALM EVER SO SLIGHTLY THROUGH THE AFTERNOON... CALMING AND BACKING
OUT OF THE SOUTHWEST OVERNIGHT THROUGH THE END OF THE PERIOD.
JTK
&&
.PREV DISCUSSION... /ISSUED 416 AM CST THU FEB 20 2014/
DISCUSSION...
PRIMARY FORECAST CONCERN REMAINS FOCUSED IN THE NEAR TERM... ON VERY
HIGH WINDS... ESPECIALLY ACROSS WRN AND NWRN OK... WHERE SUSTAINED
WINDS WILL REACH 40 MPH WITH GUSTS UP TO 60 ARE EXPECTED.
CURRENTLY... THROUGH 3 AM... ALREADY SEEING SUSTAINED WINDS OF 35-
40MPH IN THE PANHANDLE... WITH GUSTS 45-55. 09Z SFC ANALYSIS REVEALS
AN IMPRESSIVE 992MB SFC LOW TRAVERSING THE WRN OK/KS BORDER... WITH
A STOUT COLD FRONT EXTENDING FROM N/NE OF DODGE CITY S/SW ACROSS THE
PANHANDLES. RAP/NAM GUIDANCE HAS CONSISTENTLY PRODUCED 3HR PRES
CHANGE ALONG THE FRONT/SFC TROUGH OF 8 TO 10MB... ALONG WITH 0-1KM
LAPSE RATES OVER 7-8 C/KM. WITH HIGH CONFIDENCE FOR STRONG...
POTENTIALLY DAMAGING WINDS ACROSS NWRN OK... UPGRADED THE WIND
ADVISORY TO A HIGH WIND WARNING FOR PORTIONS OF NWRN OK... 40 MPH
SUSTAINED WITH GUSTS TO 60 MPH. BEST POTENTIAL FOR DAMAGING WIND
GUSTS WILL BE FROM NOW THROUGH MID/LATE MORNING.
WINDS WILL INCREASE ACROSS CENTRAL AND SRN OK AND WRN N TX THROUGH
THE MID TO LATE MORNING AS THE COLD FRONT CONTINUES TO TREK E/SE
ACROSS THE REGION. EXPECT THE COLD FRONT TO REACH THE OKC METRO SW
ALONG THE I-44 CORRIDOR NEAR NOON. SUSTAINED WINDS OF 30 TO 40
GUSTING 50 TO 55 MPH CAN BE EXPECTED THROUGH THE EARLY AFTERNOON.
MORNING COMMUTERS SHOULD TAKE CAUTION DRIVING THIS MORNING...
ESPECIALLY WHEN PILOTING A HIGH PROFILE VEHICLE ALONG E/W ROADS.
WIND GUSTS NEAR 60 MPH ARE CAPABLE OF MINOR DAMAGE TO TREES AND
POWER LINES. ALONG WITH STOUT WINDS... DRY AIR WILL FUNNEL IN ACROSS
THE REGION BEHIND THE FRONT. WITH THIS COMBINATION... ANY FIRES WILL
BURN OUT OF CONTROL QUICKLY... OUTSIDE BURNING IS HIGHLY DISCOURAGED
AND ANY FIRE WILL CAUSE A THREAT TO LIFE AND PROPERTY.
NORTH AND WEST OF THE SFC LOW... SOME ISOLATED -RA WILL CONTINUE TO
MOVE EWRD JUST NORTH OF THE OK/KS BORDER THIS MORNING. RECENT RUNS
OF THE HRRR AND NSSL WRF INDICATED SOME OF THIS ACTIVITY MAY DRIFT
SOUTH INTO FAR NRN OK. THIS IS A REASONABLE SCENARIO GIVEN THE
AVAILABLE MOISTURE AND RADAR TREND. WENT AHEAD AND STUCK SOME SLGT
CHC POPS ALONG THE NRN OK BORDER FOR THE MORNING HOURS.
WINDS WILL SLOWLY LESSEN THROUGH SUNSET FROM WEST TO EAST. REMAINING
WELL MIXED... TEMPS WILL COOL SLIGHTLY BEHIND THE FRONT... WITH AFTN
HIGHS IN THE MID 50S ACROSS NRN OK TO THE LOWER 60S ACROSS TEXOMA.
FOR FRIDAY... WINDS WILL QUICKLY BACK TO THE SW AS THE SFC HIGH
SLIDES TO TX GULF COAST. WINDS... ALTHOUGH NOT AS STRONG AS TODAY...
WILL INCREASE ONCE AGAIN. BUFR SOUNDINGS SHOW WRN N TX/SWRN OK
DRYING OUT AND MIXING QUICKLY BY THE AFTN. WITH BL FLOW OF 20 TO
30KTS... RH VALUES WILL DIP INTO THE LOWER 20S/UPPER TEENS FOR A FEW
HOURS IN THE AFTN. IN RESPONSE... VERY HIGH FIRE DANGER IS
ANTICIPATED FOR FRIDAY AS AFTN HIGHS CLIMB INTO THE MID TO UPPER 60S
AND SW WINDS ACROSS WRN OK/WRN N TX GUST INTO THE MID 20S.
BROAD TROUGHING WILL SET UP THROUGH SATURDAY WITH PSUEDO-ZONAL
FLOW ACROSS THE SRN PLAINS... S/SW SFC/BL FLOW WILL CONTINUE...
WITH WELL ABOVE AVG TEMPS PERSISTING. THE PATTERN WILL BEGIN TO
CHANGE LEADING INTO SUN... AS A WEAK H500 SHORT WAVE DEVELOPS OVER
THE ROCKIES... AND A COLD FRONT DROPS SWRD SUN MORNING. THIS IS
WHERE THE GFS/ECMWF SOLUTIONS START TO DIVERGE WITH REGARDS TO THE
SFC/BL. THE OVERALL SYNOPTIC PATTERN IS SIMILAR BTWN THE TWO...
BUT THE GFS IS MORE AGGRESSIVE WITH THE SFC HIGH SETTLING SWRD
INTO THE SRN PLAINS THROUGH MON. MEANWHILE THE ECMWF SETS UP GULF
RETURN FLOW...AND DEVELOPS SOME LIGHT QPF ACROSS CENTRAL AND ERN
OK. OF COURSE... THESE DIFFERENCES HAVE CREATED SOME CONFIDENCE
ISSUES WITH REGARDS TO TEMPS. GIVEN THE PATTERN... EXPECT A REGION
OF CANADIAN HIGH PRESSURE TO SLIDE S/SE ACROSS THE MIDWEST...
WITH TEMPS COOLING BACK AT OR NEAR NORMAL BY TUESDAY. TOOK A
CONSERVATIVE ROUTE WITH TEMPS... NOT GOING AS EXTREME AS THE
GFS...BUT A TAD COOLER THAN THE ECMWF... I GUESS YOU COULD SAY I
MADE A COMPROMISE. KEEP CHECKING BACK AS THE FORECAST FOR NEXT
WEEK BECOMES CLEARER.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 56 32 66 37 / 0 0 0 0
HOBART OK 56 31 64 35 / 0 0 0 0
WICHITA FALLS TX 61 34 69 39 / 0 0 0 0
GAGE OK 52 26 63 29 / 10 0 0 0
PONCA CITY OK 55 28 63 33 / 20 0 0 0
DURANT OK 64 38 66 41 / 10 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR OKZ008-013-
018>020-023>048-050>052.
HIGH WIND WARNING UNTIL 3 PM CST THIS AFTERNOON FOR OKZ004>007-
009>012-014>017-021-022.
TX...WIND ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR TXZ083>090.
&&
$$
11/04/04
AREA FORECAST DISCUSSION
NWS NORMAN OK
416 AM CST THU FEB 20 2014
.DISCUSSION...
PRIMARY FORECAST CONCERN REMAINS FOCUSED IN THE NEAR TERM... ON VERY
HIGH WINDS... ESPECIALLY ACROSS WRN AND NWRN OK... WHERE SUSTAINED
WINDS WILL REACH 40 MPH WITH GUSTS UP TO 60 ARE EXPECTED.
CURRENTLY... THROUGH 3 AM... ALREADY SEEING SUSTAINED WINDS OF 35-
40MPH IN THE PANHANDLE... WITH GUSTS 45-55. 09Z SFC ANALYSIS REVEALS
AN IMPRESSIVE 992MB SFC LOW TRAVERSING THE WRN OK/KS BORDER... WITH
A STOUT COLD FRONT EXTENDING FROM N/NE OF DODGE CITY S/SW ACROSS THE
PANHANDLES. RAP/NAM GUIDANCE HAS CONSISTENTLY PRODUCED 3HR PRES
CHANGE ALONG THE FRONT/SFC TROUGH OF 8 TO 10MB... ALONG WITH 0-1KM
LAPSE RATES OVER 7-8 C/KM. WITH HIGH CONFIDENCE FOR STRONG...
POTENTIALLY DAMAGING WINDS ACROSS NWRN OK... UPGRADED THE WIND
ADVISORY TO A HIGH WIND WARNING FOR PORTIONS OF NWRN OK... 40 MPH
SUSTAINED WITH GUSTS TO 60 MPH. BEST POTENTIAL FOR DAMAGING WIND
GUSTS WILL BE FROM NOW THROUGH MID/LATE MORNING.
WINDS WILL INCREASE ACROSS CENTRAL AND SRN OK AND WRN N TX THROUGH
THE MID TO LATE MORNING AS THE COLD FRONT CONTINUES TO TREK E/SE
ACROSS THE REGION. EXPECT THE COLD FRONT TO REACH THE OKC METRO SW
ALONG THE I-44 CORRIDOR NEAR NOON. SUSTAINED WINDS OF 30 TO 40
GUSTING 50 TO 55 MPH CAN BE EXPECTED THROUGH THE EARLY AFTERNOON.
MORNING COMMUTERS SHOULD TAKE CAUTION DRIVING THIS MORNING...
ESPECIALLY WHEN PILOTING A HIGH PROFILE VEHICLE ALONG E/W ROADS.
WIND GUSTS NEAR 60 MPH ARE CAPABLE OF MINOR DAMAGE TO TREES AND
POWER LINES. ALONG WITH STOUT WINDS... DRY AIR WILL FUNNEL IN ACROSS
THE REGION BEHIND THE FRONT. WITH THIS COMBINATION... ANY FIRES WILL
BURN OUT OF CONTROL QUICKLY... OUTSIDE BURNING IS HIGHLY DISCOURAGED
AND ANY FIRE WILL CAUSE A THREAT TO LIFE AND PROPERTY.
NORTH AND WEST OF THE SFC LOW... SOME ISOLATED -RA WILL CONTINUE TO
MOVE EWRD JUST NORTH OF THE OK/KS BORDER THIS MORNING. RECENT RUNS
OF THE HRRR AND NSSL WRF INDICATED SOME OF THIS ACTIVITY MAY DRIFT
SOUTH INTO FAR NRN OK. THIS IS A REASONABLE SCENARIO GIVEN THE
AVAILABLE MOISTURE AND RADAR TREND. WENT AHEAD AND STUCK SOME SLGT
CHC POPS ALONG THE NRN OK BORDER FOR THE MORNING HOURS.
WINDS WILL SLOWLY LESSEN THROUGH SUNSET FROM WEST TO EAST. REMAINING
WELL MIXED... TEMPS WILL COOL SLIGHTLY BEHIND THE FRONT... WITH AFTN
HIGHS IN THE MID 50S ACROSS NRN OK TO THE LOWER 60S ACROSS TEXOMA.
FOR FRIDAY... WINDS WILL QUICKLY BACK TO THE SW AS THE SFC HIGH
SLIDES TO TX GULF COAST. WINDS... ALTHOUGH NOT AS STRONG AS TODAY...
WILL INCREASE ONCE AGAIN. BUFR SOUNDINGS SHOW WRN N TX/SWRN OK
DRYING OUT AND MIXING QUICKLY BY THE AFTN. WITH BL FLOW OF 20 TO
30KTS... RH VALUES WILL DIP INTO THE LOWER 20S/UPPER TEENS FOR A FEW
HOURS IN THE AFTN. IN RESPONSE... VERY HIGH FIRE DANGER IS
ANTICIPATED FOR FRIDAY AS AFTN HIGHS CLIMB INTO THE MID TO UPPER 60S
AND SW WINDS ACROSS WRN OK/WRN N TX GUST INTO THE MID 20S.
BROAD TROUGHING WILL SET UP THROUGH SATURDAY WITH PSUEDO-ZONAL
FLOW ACROSS THE SRN PLAINS... S/SW SFC/BL FLOW WILL CONTINUE...
WITH WELL ABOVE AVG TEMPS PERSISTING. THE PATTERN WILL BEGIN TO
CHANGE LEADING INTO SUN... AS A WEAK H500 SHORT WAVE DEVELOPS OVER
THE ROCKIES... AND A COLD FRONT DROPS SWRD SUN MORNING. THIS IS
WHERE THE GFS/ECMWF SOLUTIONS START TO DIVERGE WITH REGARDS TO THE
SFC/BL. THE OVERALL SYNOPTIC PATTERN IS SIMILAR BTWN THE TWO...
BUT THE GFS IS MORE AGGRESSIVE WITH THE SFC HIGH SETTLING SWRD
INTO THE SRN PLAINS THROUGH MON. MEANWHILE THE ECMWF SETS UP GULF
RETURN FLOW...AND DEVELOPS SOME LIGHT QPF ACROSS CENTRAL AND ERN
OK. OF COURSE... THESE DIFFERENCES HAVE CREATED SOME CONFIDENCE
ISSUES WITH REGARDS TO TEMPS. GIVEN THE PATTERN... EXPECT A REGION
OF CANADIAN HIGH PRESSURE TO SLIDE S/SE ACROSS THE MIDWEST...
WITH TEMPS COOLING BACK AT OR NEAR NORMAL BY TUESDAY. TOOK A
CONSERVATIVE ROUTE WITH TEMPS... NOT GOING AS EXTREME AS THE
GFS...BUT A TAD COOLER THAN THE ECMWF... I GUESS YOU COULD SAY I
MADE A COMPROMISE. KEEP CHECKING BACK AS THE FORECAST FOR NEXT
WEEK BECOMES CLEARER.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 56 32 66 37 / 0 0 0 0
HOBART OK 56 31 64 35 / 0 0 0 0
WICHITA FALLS TX 61 34 69 39 / 0 0 0 0
GAGE OK 52 26 63 29 / 10 0 0 0
PONCA CITY OK 55 28 63 33 / 20 0 0 0
DURANT OK 64 38 66 41 / 10 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR OKZ008-013-
018>020-023>048-050>052.
HIGH WIND WARNING UNTIL 3 PM CST THIS AFTERNOON FOR OKZ004>007-
009>012-014>017-021-022.
TX...WIND ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR TXZ083>090.
&&
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
704 AM EST THU FEB 20 2014
.SYNOPSIS...
HIGH PRESSURE OVER CENTRAL PENNSYLVANIA EARLY THIS MORNING WILL
SLIDE EAST AND MOVE OFF THE MID-ATLANTIC COAST BY THIS AFTERNOON.
A WARM FRONT WILL LIFT NORTH ACROSS THE AREA EARLY TONIGHT...BEFORE
A STRONG COLD FRONT RACES EAST ACROSS THE COMMONWEALTH EARLY FRIDAY.
TEMPERATURES SHOULD AVERAGE NEAR OR SLIGHTLY ABOVE NORMAL INTO
WEEKEND BEFORE TRENDING COLDER INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY AM MODIS 11-3.7UM IMAGERY SHOWING EXTENSIVE VALLEY FOG AND
STRATUS ACROSS NORTHWEST PA...THE RESULT OF CLEAR SKIES AND CALM
WIND UNDER HIGH PRES SYSTEM. LAMP AND RAP DATA BOTH INDICATE AREAS
OF FOG WILL LIFT BTWN 12Z-14Z. FOCUS WILL THEN BE ON BAND OF SHRA
LIFTING NORTHEAST FROM THE OHIO VALLEY ALONG APPROACHING WARM
FRONT. REGIONAL RADAR MOSAIC ALREADY SHOWING THIS DEVELOPING BAND
OF RAIN ACROSS ILLINOIS/INDIANA...WHERE NOSE OF LL JET INTERSECTS
RETREATING 8H BAROCLINIC ZONE. ALL NEAR TERM MDL DATA TIMES THIS
FEATURE THRU CENTRAL PA BTWN 17Z-23Z. ENSEMBLE MFLUX VALUES AND
QPF PROBS SUPPORT NEAR 100 PCT CHC OF RAIN ACROSS THE NW
MTNS...WITH PROGRESSIVELY LOWER CHC OF SHOWERS FURTHER SE.
EARLY SUNSHINE WILL FADE BEHIND LOWERING/THICKENING CLOUD COVER
TODAY. HOWEVER...A RELATIVELY MILD START TO THE DAY...COMBINED
WITH DEVELOPING SOUTHERLY FLOW WEST OF RETREATING HIGH PRES SHOULD
PUSH READINGS INTO THE 40S BY AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
A STRONG MID-LVL TROUGH ENTERING THE PLAINS STATES THIS AM IS
FCST TO TAKE ON A NEGATIVE TILT AS IT REACHES THE UPPER GRT LKS
AND MS/OH VLYS TNGT. THE MAIN SYNOPTIC FEATURE OF INTEREST WILL
BE THE SHARP/TRAILING COLD FRONT WHICH WILL BE CROSSING THE
APPLCHNS AROUND 12Z FRI. THIS FRONT IS EXPECTED TO BE A FOCUS FOR
A THIN LINE OF LOW-TOPPED CONVECTION WHICH COULD REACH THE WRN
ALLEGHENIES EARLY FRI MORNING.
SPC CONVECTIVE OUTLOOKS PLACE THE AREA IN GENERAL RISK...AND
MENTIONED THIS POTENTIAL FOR LOW TOPPED SQUALL LINE WITH ELEVATED
INSTABILITY IN HWO ALONG WITH POTENTIAL FOR GUSTY WINDS /AS VERY
POTENT LLJET DEVELOPS/. THE SYSTEM IS PROGRESSIVE WHICH WILL LIMIT
HVY RAIN POTNL/FLOOD THREAT...HOWEVER ICE JAM EFFECTS COULD BE A
CONCERN. ATTM DO NOT ANTICIPATE RAPID SNOW-MELT.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A POWERFUL/NEGATIVE TILT UPPER SHORT-WAVE TROUGH WITH 200-300M/12HR
500MB HGT FALLS CROSSING THE GRT LKS/MIDWEST/TN VLY REGIONS AT THE
START OF THE PERIOD /12Z FRI/ WILL LIFT NEWD ACRS THE UPPER OH
VLY/LWR GRT LKS EARLY FRI AND CONTINUE NEWD THRU THE NORTHEAST/NEW
ENGLAND AND INTO ERN CANADA FRI NGT. AT THE SFC...AN INTENSE
OCCLUDING LOW IS FCST SIMILARLY BY THE MODELS TO SHFT NWD FROM
U.P. OF MI/LAKE SUPERIOR TO JAMES BAY. MEANWHILE...A WELL-DEFINED
TRAILING COLD FRONT EXTENDING SWD FROM TRIPLE POINT INVOF THE LWR
GRT LKS WILL RACE EWD ACRS THE APPLCHNS AND MOVE OFF THE MID-ATLC
COAST BY FRI EVE.
HIRES ARW/NMM MODEL DATA DEPICTS A SEMI-CONTINUOUS...RELATIVELY THIN
BAND OF STRONGLY FORCED LOW-TOPPED CONVECTIVE SHOWERS /WITH LITTLE
TO NO TS OR LTG/ CROSSING THE ALLEGHENY PLATEAU EARLY FRIDAY
MORNING...THEN ADVANCING QUICKLY EWD ACRS THE MID-STATE DURING THE
MID-LATE MORNING BEFORE EXITING THE ERN CWA BTWN 18-21Z. AS IS
USUALLY THE CASE WITH THESE STRONGLY FORCED COLD-SEASON
FROPAS...THERE WILL BE A RISK FOR DAMAGING WIND GUSTS
ALONG/IMMEDIATELY BEHIND THE HEAVY SHOWER BAND GIVEN VERY STRONG
WINDS ALOFT/DRY SLOT PUNCH AND MODESTLY STEEP MID-LVL LAPSE RATES.
SOUNDING DATA SHOWS A FAIRLY DEEP BLYR INVERSION IN THE PRE-
FRONTAL WARM SECTOR WHICH SHOULD BE A LIMITING FACTOR...BUT THE
STRONG FORCING/FLOW COUPLED WITH AN ISALLOBARIC PRES RISE MAX ON
THE ORDER OF 4-6MB/3HR MAY OVERCOME THE LLVL STABILITY AND PRODUCE
PEAK GUSTS IN THE 40-50 MPH RANGE. PERSISTENT..POST-FRONTAL WND
GUSTS IN THE 30-35KT RANGE SHOULD CONTINUE OVER THE WRN ZONES INTO
THE AFTN. NON-TSTM/POST-FRONTAL PEAK WND GUSTS ARE NEAR ADVY
CRITERIA...WHICH WAS CONSIDERED FOR THIS CYCLE. WILL CONTINUE TO
MENTION POTNL WIND THREAT IN THE HWO. ALTHOUGH THERE IS VERY STG
MSTR TRANSPORT/FLUX OF HI PWS VIA ANOMALOUS SLY LLJ...THE
PROGRESSIVE NATURE OF THIS SYSTEM SHOULD LIMIT QPF AMTS BTWN .5
AND 1 INCH. THESE RNFL AMTS COMBINED WITH ORDERLY SNOWMELT AND
BRIEF WARM-UP CONTINUES TO FAVOR A LOW-RISK FOR SIGNIFICANT
FLOODING...HOWEVER ICE JAM EFFECTS ALONG WITH AFOREMENTIONED
FACTORS MAY CONTRIBUTE TO MINOR/POOR DRAINAGE FLOODING IN SOME
LOCATIONS.
A SERIES OF REINFORCING FRONTS ACCOMPANYING INDIVIDUAL SHORTWAVES
ROTATING EWD AROUND THE BASE OF HUDSON/JAMES BAY POLAR VORTEX WILL
SUPPORT A GRADUAL COOL-DOWN INTO NEXT WEEK...AS THE LARGE SCALE
PATTERN REVERTS BACK TO ITS 2014 COLD SEASON FORM...WITH BLOCKING
RIDGE BECOMING REESTABLISHED OVER ALASKA AND ALLOWING A LARGE POOL
OF CONTINENTAL POLAR TO ARCTIC AIR TO BUILD OVER ERN CANADA AND
SPILL SWD INTO THE ERN U.S. THE UN-WELCOMED COOLING TREND IS THE
HIGH CONFIDENCE FCST AND SHOULD BE THE MAIN STORY INTO THE MIDDLE
OF NEXT WEEK. QUESTIONS/UNCERTAINTY REMAIN REGARDING A CLIPPER
FEATURE/COASTAL LOW DEVELOPMENT IN THE TUE-WED TIMEFRAME.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS HIGH PRES PASSES EAST OF THE AREA...EXPECT A DEVELOPING
SOUTHERLY BREEZE WILL CAUSE ANY FOG/LOW CLOUDS TO MIX OUT BTWN
12Z-14Z. LATEST LAMP/RAP OUTPUT BOTH SUPPORT THIS SCENARIO WITH A
RETURN TO WIDESPREAD VFR CONDS OVER MOST OF CENTRAL PA FOR MOST OF
THE DAYLIGHT HOURS. A BAND OF SHRA ASSOC WITH A WARM FRONT WILL
LIKELY LIFT THRU THE AREA DURING THE AFTN...AFFECTING MAINLY NW PA
WHERE MVFR REDUCTIONS ARE LIKELY AT KBFD.
A STRONG CORE OF SOUTHERLY WINDS ALOFT WILL OVERSPREAD THE REGION
THIS EVENING IN ADVANCE OF AN APPROACHING COLD FRONT. THIS WILL
LIKELY LEAD TO LLWS CRITERIA...ESP ACROSS THE W MTNS. MDL
SOUNDINGS ALSO SUPPORT THE IDEA OF WIDESPREAD MVFR /POSS IFR/ CIGS
DEVELOPING THIS EVENING IN RESPONSE TO A SURGE OF MOISTURE WORKING
INTO THE STATE ON SOUTHERLY FLOW.
COLD FRONT WILL PUSH INTO THE W MTNS BY ARND 12Z
FRIDAY...ACCOMPANIED BY SOME HEAVY SHOWERS AND PERHAPS A GUSTY
TSRA.
OUTLOOK...
FRI...WINDY. AM SHRA/LOW CIGS POSS.
SAT-MON...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD/STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
545 AM EST THU FEB 20 2014
.SYNOPSIS...
HIGH PRESSURE OVER CENTRAL PENNSYLVANIA EARLY THIS MORNING WILL
SLIDE EAST AND MOVE OFF THE MID-ATLANTIC COAST BY THIS AFTERNOON.
A WARM FRONT WILL LIFT NORTH ACROSS THE AREA EARLY TONIGHT...BEFORE
A STRONG COLD FRONT RACES EAST ACROSS THE COMMONWEALTH EARLY FRIDAY.
TEMPERATURES SHOULD AVERAGE NEAR OR SLIGHTLY ABOVE NORMAL INTO
WEEKEND BEFORE TRENDING COLDER INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
EARLY AM MODIS 11-3.7UM IMAGERY SHOWING EXTENSIVE VALLEY FOG AND
STRATUS ACROSS NORTHWEST PA...THE RESULT OF CLEAR SKIES AND CALM
WIND UNDER HIGH PRES SYSTEM. LAMP AND RAP DATA BOTH INDICATE AREAS
OF FOG WILL LIFT BTWN 12Z-14Z. FOCUS WILL THEN BE ON BAND OF SHRA
LIFTING NORTHEAST FROM THE OHIO VALLEY ALONG APPROACHING WARM
FRONT. REGIONAL RADAR MOSAIC ALREADY SHOWING THIS DEVELOPING BAND
OF RAIN ACROSS ILLINOIS/INDIANA...WHERE NOSE OF LL JET INTERSECTS
RETREATING 8H BAROCLINIC ZONE. ALL NEAR TERM MDL DATA TIMES THIS
FEATURE THRU CENTRAL PA BTWN 17Z-23Z. ENSEMBLE MFLUX VALUES AND
QPF PROBS SUPPORT NEAR 100 PCT CHC OF RAIN ACROSS THE NW
MTNS...WITH PROGRESSIVELY LOWER CHC OF SHOWERS FURTHER SE.
EARLY SUNSHINE WILL FADE BEHIND LOWERING/THICKENING CLOUD COVER
TODAY. HOWEVER...A RELATIVELY MILD START TO THE DAY...COMBINED
WITH DEVELOPING SOUTHERLY FLOW WEST OF RETREATING HIGH PRES SHOULD
PUSH READINGS INTO THE 40S BY AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
A STRONG MID-LVL TROUGH ENTERING THE PLAINS STATES THIS AM IS
FCST TO TAKE ON A NEGATIVE TILT AS IT REACHES THE UPPER GRT LKS
AND MS/OH VLYS TNGT. THE MAIN SYNOPTIC FEATURE OF INTEREST WILL
BE THE SHARP/TRAILING COLD FRONT WHICH WILL BE CROSSING THE
APPLCHNS AROUND 12Z FRI. THIS FRONT IS EXPECTED TO BE A FOCUS FOR
A THIN LINE OF LOW-TOPPED CONVECTION WHICH COULD REACH THE WRN
ALLEGHENIES EARLY FRI MORNING.
SPC CONVECTIVE OUTLOOKS PLACE THE AREA IN GENERAL RISK...AND
MENTIONED THIS POTENTIAL FOR LOW TOPPED SQUALL LINE WITH ELEVATED
INSTABILITY IN HWO ALONG WITH POTENTIAL FOR GUSTY WINDS /AS VERY
POTENT LLJET DEVELOPS/. THE SYSTEM IS PROGRESSIVE WHICH WILL LIMIT
HVY RAIN POTNL/FLOOD THREAT...HOWEVER ICE JAM EFFECTS COULD BE A
CONCERN. ATTM DO NOT ANTICIPATE RAPID SNOW-MELT.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A POWERFUL/NEGATIVE TILT UPPER SHORT-WAVE TROUGH WITH 200-300M/12HR
500MB HGT FALLS CROSSING THE GRT LKS/MIDWEST/TN VLY REGIONS AT THE
START OF THE PERIOD /12Z FRI/ WILL LIFT NEWD ACRS THE UPPER OH
VLY/LWR GRT LKS EARLY FRI AND CONTINUE NEWD THRU THE NORTHEAST/NEW
ENGLAND AND INTO ERN CANADA FRI NGT. AT THE SFC...AN INTENSE
OCCLUDING LOW IS FCST SIMILARLY BY THE MODELS TO SHFT NWD FROM
U.P. OF MI/LAKE SUPERIOR TO JAMES BAY. MEANWHILE...A WELL-DEFINED
TRAILING COLD FRONT EXTENDING SWD FROM TRIPLE POINT INVOF THE LWR
GRT LKS WILL RACE EWD ACRS THE APPLCHNS AND MOVE OFF THE MID-ATLC
COAST BY FRI EVE.
HIRES ARW/NMM MODEL DATA DEPICTS A SEMI-CONTINUOUS...RELATIVELY THIN
BAND OF STRONGLY FORCED LOW-TOPPED CONVECTIVE SHOWERS /WITH LITTLE
TO NO TS OR LTG/ CROSSING THE ALLEGHENY PLATEAU EARLY FRIDAY
MORNING...THEN ADVANCING QUICKLY EWD ACRS THE MID-STATE DURING THE
MID-LATE MORNING BEFORE EXITING THE ERN CWA BTWN 18-21Z. AS IS
USUALLY THE CASE WITH THESE STRONGLY FORCED COLD-SEASON
FROPAS...THERE WILL BE A RISK FOR DAMAGING WIND GUSTS
ALONG/IMMEDIATELY BEHIND THE HEAVY SHOWER BAND GIVEN VERY STRONG
WINDS ALOFT/DRY SLOT PUNCH AND MODESTLY STEEP MID-LVL LAPSE RATES.
SOUNDING DATA SHOWS A FAIRLY DEEP BLYR INVERSION IN THE PRE-
FRONTAL WARM SECTOR WHICH SHOULD BE A LIMITING FACTOR...BUT THE
STRONG FORCING/FLOW COUPLED WITH AN ISALLOBARIC PRES RISE MAX ON
THE ORDER OF 4-6MB/3HR MAY OVERCOME THE LLVL STABILITY AND PRODUCE
PEAK GUSTS IN THE 40-50 MPH RANGE. PERSISTENT..POST-FRONTAL WND
GUSTS IN THE 30-35KT RANGE SHOULD CONTINUE OVER THE WRN ZONES INTO
THE AFTN. NON-TSTM/POST-FRONTAL PEAK WND GUSTS ARE NEAR ADVY
CRITERIA...WHICH WAS CONSIDERED FOR THIS CYCLE. WILL CONTINUE TO
MENTION POTNL WIND THREAT IN THE HWO. ALTHOUGH THERE IS VERY STG
MSTR TRANSPORT/FLUX OF HI PWS VIA ANOMALOUS SLY LLJ...THE
PROGRESSIVE NATURE OF THIS SYSTEM SHOULD LIMIT QPF AMTS BTWN .5
AND 1 INCH. THESE RNFL AMTS COMBINED WITH ORDERLY SNOWMELT AND
BRIEF WARM-UP CONTINUES TO FAVOR A LOW-RISK FOR SIGNIFICANT
FLOODING...HOWEVER ICE JAM EFFECTS ALONG WITH AFOREMENTIONED
FACTORS MAY CONTRIBUTE TO MINOR/POOR DRAINAGE FLOODING IN SOME
LOCATIONS.
A SERIES OF REINFORCING FRONTS ACCOMPANYING INDIVIDUAL SHORTWAVES
ROTATING EWD AROUND THE BASE OF HUDSON/JAMES BAY POLAR VORTEX WILL
SUPPORT A GRADUAL COOL-DOWN INTO NEXT WEEK...AS THE LARGE SCALE
PATTERN REVERTS BACK TO ITS 2014 COLD SEASON FORM...WITH BLOCKING
RIDGE BECOMING REESTABLISHED OVER ALASKA AND ALLOWING A LARGE POOL
OF CONTINENTAL POLAR TO ARCTIC AIR TO BUILD OVER ERN CANADA AND
SPILL SWD INTO THE ERN U.S. THE UN-WELCOMED COOLING TREND IS THE
HIGH CONFIDENCE FCST AND SHOULD BE THE MAIN STORY INTO THE MIDDLE
OF NEXT WEEK. QUESTIONS/UNCERTAINTY REMAIN REGARDING A CLIPPER
FEATURE/COASTAL LOW DEVELOPMENT IN THE TUE-WED TIMEFRAME.
&&
.AVIATION /10Z THURSDAY THROUGH MONDAY/...
EARLY AM SATL IMAGERY SHOWS VALLEY FOG HAS FORMED ACROSS THE NW
MTNS. ANOTHER COUPLE HOURS OF RADIATIONAL COOLING SHOULD ENSURE
THAT LOW CLOUDS/FOG PERSIST AT KBFD THRU THE NEXT FEW HOURS.
ELSEWHERE...CONDITIONAL CLIMATOLOGY BASED ON 09Z SFC OBS SUGGEST
THERE IS ARND A 40 PCT CHC OF KUNV AND KAOO BRIEFING DIPPING TO
IFR ARND 12Z.
AS HIGH PRES PASSES EAST OF THE AREA...EXPECT A DEVELOPING
SOUTHERLY BREEZE TO CAUSE ANY FOG TO LIFT BTWN 12Z-14Z. LATEST
LAMP/RAP OUTPUT BOTH SUPPORT THIS SCENARIO WITH A RETURN TO
WIDESPREAD VFR CONDS OVER MOST OF CENTRAL PA FOR MOST OF THE
DAYLIGHT HOURS. A BAND OF SHRA ASSOC WITH A WARM FRONT WILL LIKELY
LIFT THRU THE AREA DURING THE AFTN...AFFECTING MAINLY NW PA WHERE
MVFR REDUCTIONS ARE LIKELY AT KBFD.
A STRONG CORE OF SOUTHERLY WINDS ALOFT WILL OVERSPREAD THE REGION
THIS EVENING IN ADVANCE OF AN APPROACHING COLD FRONT. THIS WILL
LIKELY LEAD TO LLWS CRITERIA...ESP ACROSS THE W MTNS. MDL
SOUNDINGS ALSO SUPPORT THE IDEA OF WIDESPREAD MVFR /POSS IFR/ CIGS
DEVELOPING THIS EVENING IN RESPONSE TO A SURGE OF MOISTURE WORKING
INTO THE STATE ON SOUTHERLY FLOW.
OUTLOOK...
FRI...WINDY. AM SHRA/LOW CIGS POSS.
SAT-MON...NO SIG WX EXPECTED.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD/STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1006 AM CST THU FEB 20 2014
.DISCUSSION...
SKIES ARE MOSTLY CLOUDY ACROSS THE FORECAST AREA THIS MORNING WITH
TEMPERATURES FROM THE MID 60S TO LOWER 70S. SURFACE LOW CURRENTLY
NEAR KANSAS/MISSOURI BORDER WITH COLD FRONT EXTENDING SOUTH FROM
THE LOW THROUGH EASTERN OKLAHOMA AND INTO CENTRAL TEXAS. THERE IS
NOT MUCH IN THE WAY OF THUNDERSTORM DEVELOPMENT AT THIS TIME BUT
AS THE FRONT MOVES INTO WESTERN ARKANSAS THUNDERSTORMS WILL BEGIN
TO DEVELOP. WILL UPDATE FORECAST TO REMOVE MORNING WORDING BUT NO
BIG CHANGES ARE NEEDED AT THIS TIME.
ARS
&&
.PREV DISCUSSION... /ISSUED 557 AM CST THU FEB 20 2014/
DISCUSSION...
..A SIGNIFICANT COLD FRONT WILL BRING SEVERE WEATHER TO THE ENTIRE
MID-SOUTH THIS AFTERNOON AND INTO THIS EVENING...
SYNOPSIS...CURRENT GOES WATER VAPOR IMAGERY SHOWS A SIGNIFICANT
LONGWAVE TROUGH DIGGING ACROSS THE CENTRAL PLAINS THIS MORNING.
THIS TROUGH WILL CONTINUE TO DEEPEN AND ACQUIRE A NEGATIVE TILT AS
IT PUSHES INTO THE MID MISSISSIPPI VALLEY THIS AFTERNOON. LATEST
SURFACE ANALYIS SHOWS AN ASSOCIATED AND IMPRESSIVE 992MB DEEPENING
LOW PRESSURE SYSTEM LOCATED JUST TO THE NORTH OF THE OKLAHOMA
PANHANDLE. THIS SURFACE CYCLONE IS EXPECTED TO TRACK NORTHEAST
THROUGH NORTHERN MISSOURI THIS AFTERNOON...AND INTO THE
GREAT LAKES REGION BY THIS EVENING. SURFACE DEWPOINTS ACROSS THE
SOUTH RANGE FROM MID TO UPPER 50S TO MID 60S AS A WARM FRONT
CONTINUES TO PUSH NORTH. THIS SYSTEM IS EXPECTED TO BECOME
OCCLUDED JUST AS IT ARRIVES INTO THE MID-SOUTH. THIS ENVIRONMENT
WILL SET THE STAGE FOR A STRONG SQUALL LINE OF THUNDERSTORMS ALONG
THE COLD FRONT TO PUSH THROUGH THIS AFTERNOON INTO TONIGHT.
IN RESPECT TO TIMING AND THREATS...
THE INITIAL CONVECTIVE MODE IS EXPECTED TO BE MIXED AND THEN
TRANSITION INTO A LINEAR MODE BY 4 PM OR SO JUST AS IT ARRIVES AT
THE MISSISSIPPI RIVER.
PREDOMINANTLY WEST OF THE MISSISSIPPI RIVER...IN THE WARM SECTOR AHEAD
OF THE COLD FRONT...LATEST HRRR MODEL SHOWS SOME ISOLATED CELLS
FORMING BY EARLY AFTERNOON AS THE MODERATE UPPER LEVEL HEIGHT FALLS ARE
OCCURRING. WITH LATEST GUIDANCE SUGGESTING ABOUT 800-1000 J/KG
SBCAPE...60 KTS OF BULK SHEAR...AND A WEAK CAP IN PLACE
.CONVECTION WILL INITIATE. THIS WILL ALLOW SOME ISOLATED CELLS TO
DEVELOP JUST AHEAD OF THE FRONT. SEMI-DISCREET SUPERCELLS AS WELL
AS SOME BOWING SEGMENTS WILL BE POSSIBLE. A FEW TORNADOES
ALONG WITH DAMAGING WINDS WILL BE THE PRIMARY THREAT.
BY LATE AFTERNOON ...THE COLD FRONT WILL CATCH UP TO THE PREFRONTAL
CONVECTION AND TRANSITION INTO A IMPRESSIVE QLCS (SQUALL LINE).
THIS IS WHEN DAMAGING WINDS WILL BECOME THE PRIMARY THREAT.
DAMAGING WINDS MAY BECOME WIDESPREAD EAST OF THE MISSISSIPPI RIVER
ALONG WITH A FEW SIGNIFICANT WIND GUSTS IN EXCESS OF 70MPH. AS THE
LINE MOVES EASTWARD...SOME EMBEDDED MESOVORTICES WITHIN THE QLCS
MAY POSE AN ISOLATED TORNADO RISK. ANY TORNADOES EMBEDDED WITHIN
THE LINE SHOULD BE SHORT TRACKED. THE SEVERE LINE SHOULD DEPART
EASTERN AREAS OF THE CWA BY LATE EVENING.
LONG TERM...FRIDAY THROUGH NEXT WEEK...
AFTER THE COLD FRONT MOVES THROUGH THIS EVENING...HIGH PRESSURE
WILL BUILD INTO THE REGION AND BRING A RETURN TO DRY WEATHER AND
CONTINUED MILD TEMPERATURES. THIS PLEASANT WEATHER SHOULD
CONTINUE FROM FRIDAY THROUGH THE FIRST HALF OF THE WEEKEND.
A COLD FRONT WILL MOVE THROUGH THE MID SOUTH ON SUNDAY BRINGING A
RETURN TO COOLER TEMPERATURES. DRY CONDITIONS SHOULD CONTINUE INTO
EARLY NEXT WEEK WITH TEMPERATURES RETURNING TO NEAR OR SLIGHTLY
BELOW AVERAGE. ANOTHER REINFORCING COLD FRONT WILL MOVE THROUGH ON
TUESDAY WITH LIGHT PRECIPITATION CHANCES AND COLDER TEMPERATURES.
AC3
&&
.AVIATION...
12Z TAF CYCLE
SURFACE LOW PRESSURE ORGANIZING ACROSS THE SOUTHERN PLAINS THIS
MORNING WILL CONTINUE TO TIGHTEN THE PRESSURE GRADIENT. AS THIS
LOW LIFTS NORTHEAST AND DEEPENS THROUGH THE AFTERNOON...A VERY
TIGHT GRADIENT WILL DEVELOP. THIS TRANSLATES INTO STRONG SOUTHERLY
WINDS AT ALL TERMINALS BEGINNING THIS MORNING AND CONTINUING INTO
THE LATE AFTERNOON AND EVENING AHEAD OF A COLD FRONTAL PASSAGE.
SUSTAINED WINDS IN EXCESS OF 25 KTS WILL BE COMMON...WITH GUSTS
BETWEEN 35-40 KTS...ESPECIALLY BY THIS AFTERNOON.
IN ADDITION...MVFR CIGS WILL CONTINUE TO ADVECT INTO THE TERMINALS
EARLY THIS MORNING...BEFORE STRONG MIXING BENEATH A STOUT CAPPING
INVERSION BASED AROUND 7 KFT AS OBSERVED FROM THE 12Z LZK
SOUNDING...HELPS TO BRING CIGS UP BY MID/LATE MORNING TO VFR
LEVELS AND BECOMING INCREASINGLY BKN.
SCATTERED SHOWERS MAY IMPACT KJBR AND KMEM FROM LATE MORNING INTO
THE EARLY AFTERNOON. THIS WILL BE PRIOR TO POTENTIAL SEVERE
THUNDERSTORMS DEVELOPING IN SCATTERED FASHION NEAR KJBR BY MID
AFTERNOON (20/20Z-20/22Z). THESE STORMS SHOULD CONSOLIDATE INTO A MORE SOLID LINE
BY LATE AFTERNOON...IMPACTING KMEM BETWEEN 20/21Z-20/23Z. THIS LINE
WILL RACE EAST AND SHOULD IMPACT KMKL BETWEEN 20/22Z-21/00Z AND KTUP
BETWEEN 21/00Z-21/02Z. DAMAGING WIND GUSTS WILL BE POSSIBLE...ESPECIALLY
EAST OF THE MISSISSIPPI RIVER. VSBYS MAY BE REDUCED TO IFR DURING
ANY STRONG CONVECTION.
WINDS WILL SWITCH NORTHWESTERLY BEHIND THE CONVECTIVE LINE AND
DIMINISH LATE TONIGHT AS SKIES EVENTUALLY CLEAR OVERNIGHT.
JLH
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 74 40 62 41 / 100 50 0 0
MKL 75 37 61 36 / 90 70 0 0
JBR 72 35 59 37 / 60 10 0 0
TUP 77 40 62 37 / 60 100 0 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE MS-
MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.
TN...WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR BENTON TN-CARROLL-
CHESTER-CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-HARDEMAN-
HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE-LAUDERDALE-MADISON-
MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
637 AM CST THU FEB 20 2014
.UPDATE...FOR 12Z AVIATION FORECAST
&&
.AVIATION...
MVFR CEILINGS HAVE MOVED NORTHWARD LAST COUPLE OF HOURS WITH IFR
AT CROSSVILLE. EVEN WITH THE WINDS TODAY NOT SURE WE CAN MIX OUT
ENOUGH TO GET BREAKS IN CLOUDS FOR VERY LONG. THINK THE MAIN
CONCERN INITIALLY TODAY WILL BE LOW LEVEL WIND SHEAR OFF SURFACE
AFFECTING LANDINGS AND TAKEOFFS. SOUTHERNLY WINDS WILL BE GUSTY
THROUGHOUT THE DAY. FRONTOGENICS GET STRONGER DURING THE AFTERNOON
IN EASTERN ARKANSAS AND THINK THIS WHERE WILL WE SEE SQUALL LINE
DEVELOP JUST AHEAD OF COLD FRONT. SQUALL LINE SHOULD BE ALONG
MISSISSIPPI RIVER AT 22Z. HRRR HAS SQUALL LINE INTO THE
CLARKSVILLE AREA AROUND 6 PM...NASHVILLE ABOUT 7 PM AND CROSSVILLE
BY 11 PM.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 9 AM THIS MORNING TO MIDNIGHT CST TONIGHT FOR
TNZ009>011-029>034-063>066-077>080.
WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR TNZ005>008-023>028-056>062-075-093>095.
&&
$$
BOYD
01
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
557 AM CST THU FEB 20 2014
.UPDATE...
UPDATED FOR THE 12Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 449 AM CST THU FEB 20 2014/
DISCUSSION...
...A SIGNIFICANT COLD FRONT WILL BRING SEVERE WEATHER TO THE ENTIRE
MID-SOUTH THIS AFTERNOON AND INTO THIS EVENING...
.SYNOPSIS...CURRENT GOES WATER VAPOR IMAGERY SHOWS A SIGNIFICANT
LONGWAVE TROUGH DIGGING ACROSS THE CENTRAL PLAINS THIS MORNING.
THIS TROUGH WILL CONTINUE TO DEEPEN AND ACQUIRE A NEGATIVE TILT AS
IT PUSHES INTO THE MID MISSISSIPPI VALLEY THIS AFTERNOON. LATEST
SURFACE ANALYIS SHOWS AN ASSOCIATED AND IMPRESSIVE 992MB DEEPENING
LOW PRESSURE SYSTEM LOCATED JUST TO THE NORTH OF THE OKLAHOMA
PANHANDLE. THIS SURFACE CYCLONE IS EXPECTED TO TRACK NORTHEAST
THROUGH NORTHERN MISSOURI THIS AFTERNOON...AND INTO THE
GREAT LAKES REGION BY THIS EVENING. SURFACE DEWPOINTS ACROSS THE
SOUTH RANGE FROM MID TO UPPER 50S TO MID 60S AS A WARM FRONT
CONTINUES TO PUSH NORTH. THIS SYSTEM IS EXPECTED TO BECOME
OCCLUDED JUST AS IT ARRIVES INTO THE MID-SOUTH. THIS ENVIRONMENT
WILL SET THE STAGE FOR A STRONG SQUALL LINE OF THUNDERSTORMS ALONG
THE COLD FRONT TO PUSH THROUGH THIS AFTERNOON INTO TONIGHT.
IN RESPECT TO TIMING AND THREATS...
THE INITIAL CONVECTIVE MODE IS EXPECTED TO BE MIXED AND THEN
TRANSITION INTO A LINEAR MODE BY 4 PM OR SO JUST AS IT ARRIVES AT
THE MISSISSIPPI RIVER.
PREDOMINANTLY WEST OF THE MISSISSIPPI RIVER...IN THE WARM SECTOR AHEAD
OF THE COLD FRONT...LATEST HRRR MODEL SHOWS SOME ISOLATED CELLS
FORMING BY EARLY AFTERNOON AS THE MODERATE UPPER LEVEL HEIGHT FALLS ARE
OCCURRING. WITH LATEST GUIDANCE SUGGESTING ABOUT 800-1000 J/KG
SBCAPE...60 KTS OF BULK SHEAR...AND A WEAK CAP IN PLACE
..CONVECTION WILL INITIATE. THIS WILL ALLOW SOME ISOLATED CELLS TO
DEVELOP JUST AHEAD OF THE FRONT. SEMI-DISCREET SUPERCELLS AS WELL
AS SOME BOWING SEGMENTS WILL BE POSSIBLE. A FEW TORNADOES
ALONG WITH DAMAGING WINDS WILL BE THE PRIMARY THREAT.
BY LATE AFTERNOON ...THE COLD FRONT WILL CATCH UP TO THE PREFRONTAL
CONVECTION AND TRANSITION INTO A IMPRESSIVE QLCS (SQUALL LINE).
THIS IS WHEN DAMAGING WINDS WILL BECOME THE PRIMARY THREAT.
DAMAGING WINDS MAY BECOME WIDESPREAD EAST OF THE MISSISSIPPI RIVER
ALONG WITH A FEW SIGNIFICANT WIND GUSTS IN EXCESS OF 70MPH. AS THE
LINE MOVES EASTWARD...SOME EMBEDDED MESOVORTICES WITHIN THE QLCS
MAY POSE AN ISOLATED TORNADO RISK. ANY TORNADOES EMBEDDED WITHIN
THE LINE SHOULD BE SHORT TRACKED. THE SEVERE LINE SHOULD DEPART
EASTERN AREAS OF THE CWA BY LATE EVENING.
.LONG TERM...FRIDAY THROUGH NEXT WEEK...
AFTER THE COLD FRONT MOVES THROUGH THIS EVENING...HIGH PRESSURE
WILL BUILD INTO THE REGION AND BRING A RETURN TO DRY WEATHER AND
CONTINUED MILD TEMPERATURES. THIS PLEASANT WEATHER SHOULD
CONTINUE FROM FRIDAY THROUGH THE FIRST HALF OF THE WEEKEND.
A COLD FRONT WILL MOVE THROUGH THE MID SOUTH ON SUNDAY BRINGING A
RETURN TO COOLER TEMPERATURES. DRY CONDITIONS SHOULD CONTINUE INTO
EARLY NEXT WEEK WITH TEMPERATURES RETURNING TO NEAR OR SLIGHTLY
BELOW AVERAGE. ANOTHER REINFORCING COLD FRONT WILL MOVE THROUGH ON
TUESDAY WITH LIGHT PRECIPITATION CHANCES AND COLDER TEMPERATURES.
AC3
&&
.AVIATION...
12Z TAF CYCLE
SURFACE LOW PRESSURE ORGANIZING ACROSS THE SOUTHERN PLAINS THIS
MORNING WILL CONTINUE TO TIGHTEN THE PRESSURE GRADIENT. AS THIS
LOW LIFTS NORTHEAST AND DEEPENS THROUGH THE AFTERNOON...A VERY
TIGHT GRADIENT WILL DEVELOP. THIS TRANSLATES INTO STRONG SOUTHERLY
WINDS AT ALL TERMINALS BEGINNING THIS MORNING AND CONTINUING INTO
THE LATE AFTERNOON AND EVENING AHEAD OF A COLD FRONTAL PASSAGE.
SUSTAINED WINDS IN EXCESS OF 25 KTS WILL BE COMMON...WITH GUSTS
BETWEEN 35-40 KTS...ESPECIALLY BY THIS AFTERNOON.
IN ADDITION...MVFR CIGS WILL CONTINUE TO ADVECT INTO THE TERMINALS
EARLY THIS MORNING...BEFORE STRONG MIXING BENEATH A STOUT CAPPING
INVERSION BASED AROUND 7 KFT AS OBSERVED FROM THE 12Z LZK
SOUNDING...HELPS TO BRING CIGS UP BY MID/LATE MORNING TO VFR
LEVELS AND BECOMING INCREASINGLY BKN.
SCATTERED SHOWERS MAY IMPACT KJBR AND KMEM FROM LATE MORNING INTO
THE EARLY AFTERNOON. THIS WILL BE PRIOR TO POTENTIAL SEVERE
THUNDERSTORMS DEVELOPING IN SCATTERED FASHION NEAR KJBR BY MID
AFTERNOON (20/20Z-20/22Z). THESE STORMS SHOULD CONSOLIDATE INTO A MORE SOLID LINE
BY LATE AFTERNOON...IMPACTING KMEM BETWEEN 20/21Z-20/23Z. THIS LINE
WILL RACE EAST AND SHOULD IMPACT KMKL BETWEEN 20/22Z-21/00Z AND KTUP
BETWEEN 21/00Z-21/02Z. DAMAGING WIND GUSTS WILL BE POSSIBLE...ESPECIALLY
EAST OF THE MISSISSIPPI RIVER. VSBYS MAY BE REDUCED TO IFR DURING
ANY STRONG CONVECTION.
WINDS WILL SWITCH NORTHWESTERLY BEHIND THE CONVECTIVE LINE AND
DIMINISH LATE TONIGHT AS SKIES EVENTUALLY CLEAR OVERNIGHT.
JLH
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 74 40 62 41 / 100 50 0 0
MKL 75 37 61 36 / 90 70 0 0
JBR 72 35 59 37 / 60 10 0 0
TUP 77 40 62 37 / 60 100 0 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR CLAY-CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-
MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR ALCORN-BENTON MS-CALHOUN-CHICKASAW-COAHOMA-DESOTO-
ITAWAMBA-LAFAYETTE-LEE MS-MARSHALL-MONROE-PANOLA-PONTOTOC-
PRENTISS-QUITMAN-TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-
UNION-YALOBUSHA.
TN...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR BENTON TN-CARROLL-CHESTER-CROCKETT-DECATUR-DYER-FAYETTE-
GIBSON-HARDEMAN-HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE-
LAUDERDALE-MADISON-MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
449 AM CST THU FEB 20 2014
.DISCUSSION...
A SIGNIFICANT COLD FRONT WILL BRING SEVERE WEATHER TO THE ENTIRE
MID-SOUTH THIS AFTERNOON AND INTO THIS EVENING.
SYNOPSIS...CURRENT GOES WATER VAPOR IMAGERY SHOWS A SIGNIFICANT
LONGWAVE TROUGH DIGGING ACROSS THE CENTRAL PLAINS THIS MORNING.
THIS TROUGH WILL CONTINUE TO DEEPEN AND ACQUIRE A NEGATIVE TILT AS
IT PUSHES INTO THE MID MISSISSIPPI VALLEY THIS AFTERNOON. LATEST
SURFACE ANALYIS SHOWS AN ASSOCIATED AND IMPRESSIVE 992MB DEEPENING
LOW PRESSURE SYSTEM LOCATED JUST TO THE NORTH OF THE OKLAHOMA
PANHANDLE. THIS SURFACE CYCLONE IS EXPECTED TO TRACK NORTHEAST
THROUGH NORTHERN MISSOURI THIS AFTERNOON...AND INTO THE
GREAT LAKES REGION BY THIS EVENING. SURFACE DEWPOINTS ACROSS THE
SOUTH RANGE FROM MID TO UPPER 50S TO MID 60S AS A WARM FRONT
CONTINUES TO PUSH NORTH. THIS SYSTEM IS EXPECTED TO BECOME
OCCLUDED JUST AS IT ARRIVES INTO THE MID-SOUTH. THIS ENVIRONMENT
WILL SET THE STAGE FOR A STRONG SQUALL LINE OF THUNDERSTORMS ALONG
THE COLD FRONT TO PUSH THROUGH THIS AFTERNOON INTO TONIGHT.
IN RESPECT TO TIMING AND THREATS...
THE INITIAL CONVECTIVE MODE IS EXPECTED TO BE MIXED AND THEN
TRANSITION INTO A LINEAR MODE BY 4 PM OR SO JUST AS IT ARRIVES AT
THE MISSISSIPPI RIVER.
PREDOMINANTLY WEST OF THE MISSISSIPPI RIVER...IN THE WARM SECTOR AHEAD
OF THE COLD FRONT...LATEST HRRR MODEL SHOWS SOME ISOLATED CELLS
FORMING BY EARLY AFTERNOON AS THE MODERATE UPPER LEVEL HEIGHT FALLS ARE
OCCURRING. WITH LATEST GUIDANCE SUGGESTING ABOUT 800-1000 J/KG
SBCAPE...60 KTS OF BULK SHEAR...AND A WEAK CAP IN PLACE
...CONVECTION WILL INITIATE. THIS WILL ALLOW SOME ISOLATED CELLS TO
DEVELOP JUST AHEAD OF THE FRONT. SEMI-DISCREET SUPERCELLS AS WELL
AS SOME BOWING SEGMENTS WILL BE POSSIBLE. A FEW TORNADOES
ALONG WITH DAMAGING WINDS WILL BE THE PRIMARY THREAT.
BY LATE AFTERNOON ...THE COLD FRONT WILL CATCH UP TO THE PREFRONTAL
CONVECTION AND TRANSITION INTO A IMPRESSIVE QLCS (SQUALL LINE).
THIS IS WHEN DAMAGING WINDS WILL BECOME THE PRIMARY THREAT.
DAMAGING WINDS MAY BECOME WIDESPREAD EAST OF THE MISSISSIPPI RIVER
ALONG WITH A FEW SIGNIFICANT WIND GUSTS IN EXCESS OF 70MPH. AS THE
LINE MOVES EASTWARD...SOME EMBEDDED MESOVORTICES WITHIN THE QLCS
MAY POSE AN ISOLATED TORNADO RISK. ANY TORNADOES EMBEDDED WITHIN
THE LINE SHOULD BE SHORT TRACKED. THE SEVERE LINE SHOULD DEPART
EASTERN AREAS OF THE CWA BY LATE EVENING.
...FRIDAY THROUGH NEXT WEEK...
AFTER THE COLD FRONT MOVES THROUGH THIS EVENING...HIGH PRESSURE
WILL BUILD INTO THE REGION AND BRING A RETURN TO DRY WEATHER AND
CONTINUED MILD TEMPERATURES. THIS PLEASANT WEATHER SHOULD
CONTINUE FROM FRIDAY THROUGH THE FIRST HALF OF THE WEEKEND.
A COLD FRONT WILL MOVE THROUGH THE MID SOUTH ON SUNDAY BRINGING A
RETURN TO COOLER TEMPERATURES. DRY CONDITIONS SHOULD CONTINUE INTO
EARLY NEXT WEEK WITH TEMPERATURES RETURNING TO NEAR OR SLIGHTLY
BELOW AVERAGE. ANOTHER REINFORCING COLD FRONT WILL MOVE THROUGH ON
TUESDAY WITH LIGHT PRECIPITATION CHANCES AND COLDER TEMPERATURES.
AC3
&&
.AVIATION...
06Z TAF SET
A WARM FRONT HAS LIFTED NORTHWARD ACROSS THE AREA. SE WINDS ARE
OCCURRING EVERYWHERE EXCEPT KJBR BUT EXPECT THEM TO SHIFT SHORTLY.
ALL TAF SITES ARE VFR FOR NOW. STRATUS WILL INVADE THE AREA FROM
THE SOUTH BETWEEN 8-12Z. CIGS WILL DROP TO MVFR DURING THAT TIME.
THE MVFR CIGS WILL CONTINUE UNTIL A COLD FRONT PUSHES THROUGH.
KJBR WILL BE IMPACTED FIRST BETWEEN 16-20Z. SCATTERED TSRAS WILL
DEVELOP AHEAD OF THE FRONT AND EVENTUALLY WILL FORM A SQUALL LINE
ROUGHLY AROUND THE MISSISSIPPI RIVER. TSRAS WILL IMPACT KMEM
BETWEEN 19-22Z...KMKL BETWEEN 20-24Z AND KTUP BETWEEN 23-03Z. STRONG
S WINDS WILL OCCUR AHEAD OF THE FRONT. EXPECT SPEEDS TO INCREASE
TO 15-20 KTS SUSTAINED WITH GUSTS UP TO 30 KTS AFTER 14-16Z. WINDS
WILL TURN AROUND TO THE NW BEHIND THE FRONT WITH SPEEDS
EXPECTED TO DIMINISH AS WELL AT THAT TIME.
KRM
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 74 40 62 41 / 100 50 0 0
MKL 75 37 61 36 / 90 70 0 0
JBR 72 35 59 37 / 60 10 0 0
TUP 77 40 62 37 / 60 100 0 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR CLAY-CRAIGHEAD-CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-
MISSISSIPPI-PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR ALCORN-BENTON MS-CALHOUN-CHICKASAW-COAHOMA-DESOTO-
ITAWAMBA-LAFAYETTE-LEE MS-MARSHALL-MONROE-PANOLA-PONTOTOC-
PRENTISS-QUITMAN-TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-
UNION-YALOBUSHA.
TN...WIND ADVISORY FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR BENTON TN-CARROLL-CHESTER-CROCKETT-DECATUR-DYER-FAYETTE-
GIBSON-HARDEMAN-HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE-
LAUDERDALE-MADISON-MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
411 AM CST THU FEB 20 2014
.UPDATE...
ISSUED AT 410 AM CST THU FEB 20 2014
NOTE HEADLINE CHANGES BELOW. LATEST WSW STATEMENT WILL BE OUT
SHORTLY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 358 AM CST THU FEB 20 2014
POWERFUL/DANGEROUS WINTER STORM IMPACTS THE AREA TODAY INTO FRIDAY.
CURRENTLY SEEING SOME LIGHT/MOSTLY LIQUID FORM PRECIPITATION WORKING
NORTHEAST WARD INTO PORTIONS OF NORTHEAST IA/SOUTHWEST WI EARLY THIS
MORNING. THIS IS IN RESPONSE TO A MID-LEVEL TROUGH AHEAD OF THE
POTENT TROUGH AND STRONG SURFACE CYCLOGENESIS TAKING PLACE OVER THE
SOUTHERN PLAINS. LOOK FOR THIS FIRST AND ASSOCIATED RAIN/SLEET/SNOW
TO EXIT EAST THIS MORNING. THERE MAY BE A A LULL IN THE ACTION BY
MID-MORNING..TRANSITIONING TO MORE OF A DRIZZLE. EXPECTING SOME
LIGHT ICING ON ROADWAYS/SIDEWALKS WHERE TEMPERATURES WILL BE AT OR
EVEN BELOW FREEZING.
THEN...LOOK FOR THE MAIN/POWERFUL STORM SYSTEM TO LIFT FROM THE
SOUTHERN PLAINS TO JUST EAST OF GRANT COUNTY IN SOUTHWEST WI BY
00Z/6PM. AS THE LOW APPROACHES...MODEL SHOW MAXIMUM TEMPERATURES
ALOFT INCREASING INTO THE +3 TO +8C RANGE ACROSS A SMALL PART OF
NORTHEAST IA INTO SOUTHWEST AND CENTRAL WI. AS A RESULT...MUCH OF
THE PRECIPITATION FALLING ACROSS THIS AREA TODAY WILL BE IN THE FORM
OF RAIN. MEANWHILE...FARTHER WEST ACROSS NORTHEAST IA/SOUTHEAST
MN/NORTHWEST WI...TEMPERATURE PROFILES SUPPORT SNOW. THIS WILL BE
MAINLY NORTHWEST OF A LINE FROM NEW HAMPTON IA/PRESTON MN/WINONA
LINE. STRONG FRONTOGENESIS/NEGATIVE EPV SUPPORTS THE THREAT FOR
THUNDERSNOW AND INTENSE SNOW RATES EASILY 1 IN/HR THIS AFTERNOON. IN
ADDITION...STRONG NORTHWEST WINDS WILL BE KICKING IN BY LATER THIS
AFTERNOON ON THE BACKSIDE OF THE DEEP 982MB LOW. THINKING THIS AREA
SHOULD SEE SNOWFALL IN THE 5-8 INCH RANGE IN THE NOON TO 6 PM
TIMEFRAME. IN ADDITION...STRONG NORTHWEST WINDS WILL BE KICKING IN
LATER IN THE AFTERNOON FOR WIDESPREAD BLOWING AND DRIFTING AND
OCCASIONAL WHITEOUT CONDITIONS.
LOOK FOR THE HEAVY SNOW TO CONTINUE THROUGH THE EVENING OVER
NORTHEAST IA/SOUTHEAST MN INTO NORTHERN WI TONIGHT AS THE LOW PULLS
TOWARD LAKE SUPERIOR BY 6 AM. PRECIPITATION WILL TRANSITION QUICKLY
TO ALL SNOW ACROSS THE REST OF THE AREA AS COLDER AIR IS DRAWN IN BY
THE SYSTEM. VERY STRONG/GUSTY NORTHWEST WINDS WILL BE IN PLACE
ACROSS THE ENTIRE AREA WITH GUSTS APPROACHING 50 MPH ACROSS THE MORE
OPEN AREAS OF NORTHEAST IA/SOUTHEAST MN...CONTINUING THE BLOWING AND
DRIFTING. LOOK FOR THE SNOW TO SLOWLY TAPER LATER TONIGHT/AFTER
MIDNIGHT THROUGH FRIDAY MORNING FROM SOUTH TO NORTH AS THE LOW PULLS
INTO THE U.P...BUT STRONG GUSTY WINDS WILL CONTINUE TO CAUSE BLOWING
AND DRIFTING PROBLEMS.
BY THE TIME ALL IS SAID AND DONE AROUND NOON FRIDAY...6-12 INCH SNOW
ACCUMULATIONS CAN BE EXPECTED ACROSS PORTIONS OF NORTHEAST
IA/SOUTHEAST MN INTO NORTH CENTRAL WI.
DUE TO THE COMPLEXITY OF THE THERMAL PROFILE OF THIS POWERFUL STORM
AND AFFECT IT HAS ON SNOWFALL AMOUNTS AND PRECIPITATION
TYPES...HEADLINES WERE ADJUSTED/EXTENDED OVERNIGHT.
FOR FULL DETAILS INCLUDING WINTER WEATHER HEADLINES/GRAPHICAL
DISPLAY OF SNOW AMOUNTS AND OTHER HAZARDS TIED TO THE STORM...SEE
OUR NEWS STORY ON OUR INTERNET PAGE AT WWW.WEATHER.GOV/LACROSSE.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 400 AM CST THU FEB 20 2014
WITH THE DEPARTING STORM SYSTEM FRIDAY...LOOK FOR COLDER NORTHWEST
FLOW ALOFT TO KICK IN INTO NEXT WEEK. UNSEASONABLY COLD TEMPERATURES
WILL RESULT WITH HIGHS SATURDAY STARTING OFF IN THE TEENS AND LOWER
20S...THEN DROPPING INTO THE UPPER SINGLE DIGITS AND TEENS ABOVE ZERO
BY WEDNESDAY. OVERNIGHT LOWS ARE EXPECTED TO DIP INTO THE SINGLE
DIGITS ABOVE AND BELOW ZERO...POSSIBLY TEEN/NEAR 20 BELOW BY
WEDNESDAY NIGHT. ALSO...APPEARS THERE WILL BE A SHOT AT SOME LIGHT
SNOW MONDAY/MONDAY NIGHT TIME FRAME AS A WEAK MID-LEVEL TROUGH
ROTATES THROUGH THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1122 PM CST WED FEB 19 2014
NO SIGNIFICANT FORECAST CHANGES EXPECTED BASED ON THE LATEST MODEL
INFORMATION. REGIONAL RADARS SHOWING THE FIRST WAVE OF
PRECIPITATION OCCURRING OVER SOUTHERN IOWA MOVING NORTHEAST. THE
20.00Z NAM AND 20.03Z HRRR SHOW THE BULK OF THIS PRECIPITATION
MOVING PAST THE TAF SITES TO THE SOUTHEAST. STILL EXPECTING SOME
LIGHT PRECIPITATION TO HIT THE TAF SITES AS THIS COMES IN AND THE
CONCERN REMAINS WHETHER THERE WILL BE ICE AVAILABLE IN THE CLOUDS
AND IF THERE IS...WILL THE WARM LAYER ABOVE THE SURFACE BE ENOUGH
FOR COMPLETE OR PARTIAL MELTING. HAVE CONTINUED THE TREND OF
SHOWING LIGHT SNOW WITH A PERIOD OF FREEZING RAIN AND SLEET
POSSIBLE AT KLSE AND INTRODUCED THE FREEZING RAIN THREAT AT KRST
AS WELL. BY MID MORNING...LOW LEVEL TEMPERATURES STILL EXPECTED TO
BE WARM ENOUGH FOR A RAIN/SNOW MIX AT KLSE WHILE PRIMARILY SNOW IS
EXPECTED AT KRST. THIS INITIAL PRECIPITATION SHOULD PRODUCE
PRIMARILY MVFR CONDITIONS. CONDITIONS THEN DETERIORATE RAPIDLY
DURING THE AFTERNOON AS THE STRONG FORCING MOVES IN WITH MODERATE
TO HEAVY SNOW AND IFR CONDITIONS INTO THE EVENING HOURS. ONCE THE
SURFACE LOW MOVES PAST...THE FALLING SNOW WILL START TO DECREASE
IN INTENSITY BUT THE WINDS WILL BECOME STRONG OUT OF THE WEST WITH
GUSTS OF 30 TO 40 KNOTS WHICH WILL PRODUCE BLOWING SNOW AT BOTH
AIRPORTS AND KEEP KRST IN IFR CONDITIONS.
.HYDROLOGY...(FOR TODAY INTO EARLY THIS EVENING)
ISSUED AT 358 AM CST THU FEB 20 2014
WITH WARMER AIR WRAPPING INTO THIS INTENSE LOW...MORE RAINFALL WILL
BE SEEN ACROSS SOUTHWEST INTO CENTRAL WI. WITH FROZEN GROUND AND
SEWERS PLUGGED WITH ICE/SNOW...LOOK FOR PONDING OF WATER AND SOME
RUNOFF INTO STREAMS FOR LOCAILZED RISES WHERE STREAM ARE RUNNING
UNFROZEN.
&&
.HYDROLOGY...(FOR TODAY INTO EARLY THIS EVENING)
ISSUED AT 358 AM CST THU FEB 20 2014
WITH WARMER AIR WRAPPING INTO THIS INTENSE LOW...MORE RAINFALL WILL
BE SEEN ACROSS SOUTHWEST INTO CENTRAL WI. WITH FROZEN GROUND AND
SEWERS PLUGGED WITH ICE/SNOW...LOOK FOR PONDING OF WATER AND SOME
RUNOFF INTO STREAMS FOR LOCAILZED RISES WHERE STREAM ARE RUNNING
UNFROZEN.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY UNTIL NOON CST FRIDAY FOR WIZ041>044-
053>055-061.
WINTER STORM WARNING FROM 9 AM THIS MORNING TO NOON CST FRIDAY
FOR WIZ017-029-032>034.
MN...WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR
MNZ086>088-094-095.
BLIZZARD WARNING FROM 9 AM THIS MORNING TO NOON CST FRIDAY FOR
MNZ079-086-087-094-095.
WINTER WEATHER ADVISORY UNTIL NOON CST FRIDAY FOR MNZ096.
WINTER STORM WARNING FROM 9 AM THIS MORNING TO NOON CST FRIDAY
FOR MNZ088.
IA...WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR
IAZ008>010-018-019-029.
BLIZZARD WARNING FROM 9 AM THIS MORNING TO NOON CST FRIDAY FOR
IAZ008>010-018-019-029.
WINTER WEATHER ADVISORY UNTIL NOON CST FRIDAY FOR IAZ011-030.
&&
$$
UPDATE...ZT
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...04
AREA FORECAST DISCUSSION
NWS ALBANY NY
1254 PM EST THU FEB 20 2014
.SYNOPSIS...
A STRONG LOW PRESSURE SYSTEM WILL NORTHWARD INTO THE WESTERN GREAT
LAKES REGION TONIGHT. ITS ASSOCIATED WARM FRONT WILL PROVIDE A
PERIOD OF WINTRY PRECIPITATION FOR MANY AREAS TONIGHT.
HOWEVER...WARMER AIR WILL EVENTUALLY LIFT NORTHWARD TO RESULT IN
MOSTLY RAIN FRIDAY ALONG WITH A SLIGHT CHANCE FOR THUNDERSTORMS. A
COLD FRONT PASSES ACROSS THE AREA FRIDAY AFTERNOON WITH A RETURN TO
COOLER WEATHER FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM EST...HIGH PRESSURE CONTINUES TO MOVE EAST OF THE MID
ATLANTIC AND DELMARVA REGION EARLY THIS AFTERNOON. A WARM FRONT
CONTINUES TO LIFT NORTH/NORTHEAST FROM THE OHIO VALLEY AND LOWER
MID ATLANTIC REGION. SUNSHINE...IS GIVING WAY TO PARTIAL SUNSHINE
WITH INCREASING MID AND HIGH CLOUDS FROM THE WEST. THESE CLOUDS
ARE MOVING IN QUICK WHICH WILL SLOW DOWN THE WARMING...WHICH HAS
BEEN SUBSTANTIAL TODAY WITH LOWER TO MID 40S IN MANY OF THE VALLEY
AREAS. SOME SLIGHT TWEAK WERE MADE WITH THE MAX TEMP AND TRENDS.
CLOUDS WERE ALSO RETOOLED BASED ON THE SATELLITE PICTURE. THE
LATEST HRRR 3-KM REF PRODUCT IS ALSO A TAD BIT SLOWER THIS RUN
WITH THE STRONG ISENTROPIC LIFT ON THE 285/290K SFC NOT ARRIVING
UNTIL ABOUT 23Z-01Z. THE POPS WERE RETRENDED SLIGHTLY FAVORING A
RAIN/SNOW TRANSITION ESPECIALLY FROM THE CAPITAL REGION NORTH. THE
INTENSITY OF THE PCPN...AND THE ACTUAL WET BULB COOLING WILL
DETERMINE HOW FAR SOUTH THE HEAVIER PCPN/SNOW WILL BE. THE
HEADLINES WILL REMAIN FOR NOW...AS FAR SOUTH AS THE CAPITAL
REGION.
TONIGHT...H2O VAPOR IMAGERY REVEALS A VERY POTENT SHORT WAVE
EJECTING OUT ONTO THE CENTRAL PLAINS. MEANWHILE...A SUBTROPICAL
PLUME OF MOISTURE EXTENDED FROM THE CENTRAL PACIFIC...ACROSS BAJA
CALIFORNIA AND ONTO THE SOUTHERN PLAINS AND MID WEST. PWATS WITHIN
THIS DEEPER MOISTURE WAS BETWEEN 1-3 STANDARD DEVIATIONS ABOVE
NORMAL AS NCEP MODEL SUITE AND SHORT TERM GUIDANCE /RUC13-HRRR/
SUGGEST A RAPID INCREASE IN MOISTURE TRANSPORT EVOLVING THROUGH
THE DAY TODAY. LOW LEVEL JET GREATER THAN 50KTS IS ALSO EXPECTED
TO DEVELOP TO ASSIST WITH THE MOISTURE TRANSPORT NORTHWARD INTO
OUR CWA BY LATE THIS AFTERNOON. THERMAL PROFILES FROM BUFR
PROFILES SUGGEST A RAIN/SNOW LINE SOMEWHERE ALONG OR JUST SOUTH OF
I90 PER WET BULB ZERO.
CROSS SECTIONS TONIGHT POINT TOWARD ANOTHER IMPRESSIVE 2D FGEN
ENHANCEMENTS AS PER CSTAR RESEARCH SUGGESTS BANDED STRUCTURES TO
THE PRECIP DEVELOPING OVER THE REGION. PER THE NCEP MODEL
SUITE...THIS BAND WILL MIGRATE FROM SOUTH TO NORTH THROUGH THIS
EVENING AND MAY LINGER ACROSS PORTIONS OF THE ADIRONDACKS
OVERNIGHT. IN ADDITION...INCREASING SOUTHERLY FLOW FAVORS UPSLOPE
CONDITIONS FURTHER ENHANCING THE PRECIP AMOUNTS. AS FOR
PRECIP...THERMAL PROFILES ARE TRICKY. WITHIN THE VICINITY OF I90
CORRIDOR...THE INITIAL ONSET OF PRECIP WILL LIKELY BE A RAIN/SNOW
TO SNOW THIS EARLY EVENING WITH A TRANSITION TO SLEET AND PERHAPS
A PERIOD OF FREEZING RAIN THROUGH THE LATER EVENING HOURS AS
WARMER AIR ALOFT /H850/ CLIMBS ABOVE FREEZING. DUE TO THE ENHANCE
2D FGEN AND A LAYER OF NEGATIVE EPV JUST ABOVE THIS LAYER WITH >20
UBAR/SEC OMEGA...THIS POINTS TOWARD THE POTENTIAL FOR AN MODERATE
TO HEAVY BAND OF PRECIP LIFTING NORTHWARD WITH A QUICK
ACCUMULATING SNOW THIS EVENING. THE BETTER CHANCE FOR A QUICK
ACCUMULATING SNOWFALL WILL BE NORTH OF I90 WHERE UP TO 4 INCHES
COULD FALL IN A SHORT PERIOD OF TIME. DUE TO THE COMPLEX THERMAL
PROFILES AND THE HIGH POTENTIAL FOR BANDED PRECIP STRUCTURES...WE
WILL HOIST ADVISORIES FOR THE NORTHERN 2/3RDS OF THE CWA. SOUTHERN
PORTIONS APPEAR TO REMAIN ABOVE FREEZING FOR MOST OF THE PRECIP TO
FALL AS RAIN. AS THE WARMER AIR CONTINUES ALOFT...THE PRECIP TO
THE NORTH OF I90 MIXING WITH SLEET AND FREEZING RAIN. THOSE LOWER
VALLEY LOCATIONS WITHIN THE MOUNTAINS COULD EXPERIENCE A PERIOD OF
ACCUMULATING ICE WITH CURRENT PROJECTIONS UP TO TWO TENTHS OF AN
INCH IN A FEW LOCATIONS WITH MOST AREA EXPECTED TO REMAIN BELOW
THAT VALUE.
TEMPERATURES WILL FOLLOW A NON-DIURNAL CURVE THE NEXT 24 HOURS AS
STRENGTHENING WARM ADVECTION UNFOLDS AS WARM FRONT LIFTS NORTHWARD.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
LOW LEVEL JET PER THE GEFS/SREF ENSEMBLES WILL RANGE BETWEEN 2-3
STANDARD DEVIATIONS ABOVE NORMAL ACROSS THE REGION ALONG WITH
THOSE HIGH PWATS FOR THIS TIME OF THE YEAR. AS TEMPERATURES
CONTINUE TO CLIMB ABOVE FREEZING...THIS WILL REDUCE THE WINTRY
MIXTURE TO MAINLY RAIN. THE FORECAST AREA IS EXPECTED TO BE WELL
WITHIN THE WARM SECTOR AS H850 TEMPS CLIMB TOWARD +8C. THIS WILL
INCREASE THE SNOW MELT ALONG WITH DEWPOINTS CLIMBING ABOVE
FREEZING. PATCHY FOG IS EXPECTED ALONG WITH THE INCREASE IN
RAINFALL POTENTIAL. IN FACT...FORECAST SOUNDINGS SUGGEST LIFTING
PARCELS ABOVE THE BOUNDARY LAYER YIELDS THE POSSIBILITY FOR
THUNDERSTORMS AS SHOWALTERS DROP BELOW 0C. IN COORDINATION WITH
SPC...WE WILL INTRODUCE A SLIGHT CHANCE FOR THUNDER ACROSS THE
ENTIRE REGION. RAINFALL RATES ALONG THE STRONG BAROCLINIC FRONTAL
ZONE COULD BE RATHER HIGH FOR THIS TIME OF THE YEAR. AT THIS
TIME...NO HYDRO RELATED HEADLINES BUT COULD SEE SOME URBAN AND
SMALL STREAM ISSUES AS PERHAPS ICE JAMS DUE TO BREAK UP /MORE
BELOW IN THE HYDRO SECTION/. TEMPERATURES FOR MOST OF THE AREA ARE
EXPECTED TO BE WELL INTO 40S. THE STRONG WINDS ALOFT SHOULD REMAIN
ABOVE THE BOUNDARY LAYER WITH NOT MUCH MIXING EXPECTED.
FROPA IS EXPECTED AROUND THE 21Z TIME FRAME. THE H850 TEMPS PLUNGE
FROM AROUND +8C TO AROUND -6C IN ABOUT 6HRS. THERE COULD A PERIOD
OF RAIN MIXING WITH A LITTLE SNOW IN THE WAKE OF THE FROPA BUT
ACCUMULATIONS ARE NOT EXPECTED FOR MOST OF THE REGION. WHERE SOME
LIGHT ACCUMULATIONS ARE POSSIBLE WILL BE ACROSS THE ADIRONDACKS AS
AN UPPER LEVEL IMPULSE ROTATES ACROSS THIS REGION AROUND THE
PERIPHERY OF THE DEEP UPPER LOW NEAR JAMES BAY AND SOME LAKE
ONTARIO CONTRIBUTION. TEMPERATURES WILL DIP BACK BELOW FREEZING
FRIDAY NIGHT AS SOME BLACK ICE COULD FORM ON THOSE UNTREATED
SURFACES.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
MUCH OF THE PERIOD WILL FEATURE THE RETURN OF BELOW NORMAL
TEMPERATURES...ALONG WITH A FEW POSSIBLE EPISODES OF SNOW SHOWERS
AND/OR LIGHT SNOW...AS MID/UPPER LEVEL HEIGHTS FALL CONSIDERABLY
ACROSS SOUTHERN AND EASTERN CANADA...INTO THE CENTRAL AND EASTERN
U.S.
HERE ARE SOME MORE SPECIFIC DETAILS...
SAT-SAT NT...IN THE WAKE OF FRIDAY/S FRONTAL SYSTEM...A BROAD
SOUTHWEST FLOW IN THE MID AND UPPER LEVELS OF THE TROPOSPHERE WILL
ALLOW FOR ONLY GRADUAL LOW LEVEL COOLING TO OCCUR. THEREFORE...WE
EXPECT TEMPS TO REMAIN ABOVE SEASONAL LEVELS ON SAT...RISING INTO
THE 40S IN MOST VALLEY AREAS...AND 30S ACROSS HIGHER ELEVATIONS. IT
IS POSSIBLE THAT SOME PORTIONS OF THE MID HUDSON VALLEY AND LOWER
ELEVATIONS IN NW CT APPROACH 50 WITH SUNSHINE AND A DOWNSLOPING
WESTERLY LOW LEVEL FLOW. IN THE AFTERNOON...A WEAK UPPER LEVEL
IMPULSE MAY BRING SOME CLOUDS...AND PERHAPS SOME LIGHT SHOWERS OF
RAIN/SNOW IN THE AFTERNOON/EVENING FOR CENTRAL AND NORTHERN AREAS.
FOR SAT NT...TEMPS WILL FALL INTO THE 20S IN MOST AREAS...WITH SOME
TEENS ACROSS THE WESTERN ADIRONDACKS...WHERE SOME SNOW SHOWERS WILL
ALSO BE POSSIBLE.
SUN-MON NT...THE TREND TOWARD COLDER TEMPS WILL CONTINUE...WITH
SUNDAY MAX TEMPS REACHING THE MID 30S TO LOWER 40S IN VALLEYS...AND
20S TO LOWER 30S ACROSS HIGHER ELEVATIONS...WHILE MONDAY MAXES ONLY
REACH THE 20S IN VALLEYS...AND TEENS ACROSS HIGHER ELEVATIONS. SOME
SNOW SHOWERS/FLURRIES WILL BE POSSIBLE ACROSS CENTRAL AND NORTHERN
AREAS LATE SUN INTO MONDAY NT. TEMPS MON NT WILL FALL INTO THE
SINGLE DIGITS IN MOST AREAS.
TUE-WED...MODEL UNCERTAINTY INCREASES WITH REGARD TO THE HANDLING OF
POTENTIAL FAST MOVING UPPER LEVEL IMPULSES DURING THIS TIME PERIOD.
THE 00Z/20 ECMWF HINTS AT ONE POSSIBLE IMPULSE AFFECTING THE REGION
TUE...ESP CENTRAL AND SOUTHERN AREAS...WITH SOME LIGHT SNOW...WHILE
THIS SIGNAL IS SOMEWHAT WEAKER IN THE 00Z/20 GFS AND GEFS. WILL
TREND TOWARD THE ECMWF SOLUTION...WITH SLIGHT CHC POPS ACROSS
CENTRAL AND SOUTHERN AREAS FOR SNOW SHOWERS...ALONG WITH SOME CHC
POPS ACROSS THE WESTERN ADIRONDACKS. BOTH THE 00Z/20 ECMWF/GFS AND
GEFS HINT AT ANOTHER IMPULSE PASSING MAINLY SOUTH OF THE REGION ON
WED...ALTHOUGH THE GEFS ARE A LITTLE FURTHER NORTH WITH POSSIBLE
MEASURABLE PRECIPITATION. WILL THEREFORE INDICATE LOW CHC POPS FOR
LIGHT SNOW ON WED. OTHERWISE...TEMPS WILL REMAIN WELL BELOW NORMAL
DURING THIS PERIOD...WITH DAYTIME MAXES MAINLY IN THE 20S FOR
VALLEYS...AND TEENS FOR HIGHER ELEVATIONS...AND OVERNIGHT MIN TEMPS
MAINLY IN THE SINGLE DIGITS TO LOWER TEENS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
HIGH AND MID LEVEL CLOUDS WILL CONTINUE TO INCREASE AND THICKEN THIS
AFTERNOON AHEAD OF A WARM FRONT APPROACHING FROM THE OHIO VALLEY AND
GREAT LAKES REGION. PRECIPITATION IS EXPECTED TO DEVELOP THIS
EVENING...BUT WITH SLIGHTLY LATER TIMING COMPARED TO PREVIOUS
FORECASTS. STILL EXPECTING A WINTRY MIX AT THE ONSET...ESPECIALLY
FROM KALB/KPSF TO KGFL. SOME SLEET MAY BRIEFLY MIX IN AT KPOU. KALB
WILL HAVE A FAIRLY QUICK CHANGE TO ALL RAIN LATER THIS EVENING...DUE
TO SOUTHERLY FLOW UP THE HUDSON VALLEY. KGFL WILL HOLD ONTO FROZEN
PRECIP THE LONGEST...INTO FRIDAY MORNING.
CONDITIONS WILL DETERIORATE TO MVFR THEN IFR THIS EVENING. SOLID
IFR/LIFR EXPECTED OVERNIGHT AND THROUGH MUCH OF FRIDAY MORNING DUE
TO RELATIVELY WARM/MOIST AIR MOVING OVER A DEEP SNOWPACK. RAIN WILL
CONTINUE THROUGH MUCH OF FRIDAY BEFORE A COLD FRONT PASSES THROUGH
DURING THE AFTERNOON.
WINDS WILL BE SOUTH-SOUTHEAST AROUND 4-8 KT...BECOMING LIGHT AND
VARIABLE TONIGHT INTO FRIDAY MORNING.
OUTLOOK...
FRIDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...FG.
FRIDAY NIGHT TO SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN. SUNDAY
NIGHT TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
THE SNOW DEPTHS ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN
NEW ENGLAND ARE GENERALLY FROM 1 TO 3 FEET.
MODERATING TEMPERATURES REMAIN IN THE FORECAST WHICH WILL REACH
ITS PEAK DURING FRIDAY. SNOW MELT WILL INITIALLY BE SMALL AT FIRST
WITH A GRADUAL INCREASE DURING FRIDAY.
RAINFALL TOTALS TONIGHT AND FRIDAY ARE FORECAST TO GENERALLY BE
IN THE HALF AN INCH TO ONE INCH RANGE BASED ON THE LATEST
NERFC/WPC GUIDANCE. THE HIGHER TOTALS ARE EXPECTED ACROSS THE SRN
DACKS REGION...WHERE ISOLATED AMOUNTS TO AN INCH AND A HALF ARE
POSSIBLE. THERE WILL BE A PERIOD OF WINTRY MIXTURE AT THE ONSET
AND THROUGH MOST OF TONIGHT WITH A TRANSITION TO RAIN FROM
SOUTHWEST TO NORTHEAST. WE EXPECT MUCH OF THE RAINFALL WILL SOAK
INTO THE DEEP SNOW PACK.
PER THE LATEST MMEFS...THERE IS A SMALL POTENTIAL FOR FLOODING
ACROSS THE WESTERN MOHAWK VALLEY BUT DUE TO ICE IN PLACE...FOCUS
WILL BE THE ICE JAM POTENTIAL. HOWEVER...ACCUMULATING TEMPERATURES
REMAINING ABOVE FREEZING WILL BE MINIMAL WHICH SHOULD KEEP THINGS
IN CHECK. NEVERTHELESS...IT IS NOT ZERO AS WE WILL CONTINUE TO
HIGHLIGHT WITHING THE HWO.
COLDER TEMPERATURES ARE EXPECTED FRIDAY NIGHT...AND LATER IN THE
WEEK. AN ISOLATED OR LOCALIZED ICE JAM THREAT WILL CONTINUE TO BE
MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
THE MONTHLY SNOWFALL TOTAL FOR FEBRUARY AT THE ALBANY INTERNATIONAL
AIRPORT IS AT 27.7 INCHES THROUGH THE 19TH. IT IS THE 7TH
SNOWIEST FEBRUARY ON RECORD.
TOP 10 SNOWIEST FEBRUARYS ALBANY
1. 40.7 INCHES 1893
2. 34.5 INCHES 1962
3. 32.3 INCHES 1926
4. 31.7 INCHES 1950
5. 30.1 INCHES 2011
6. 28.6 INCHES 1993
7. 27.7 INCHES 2014
8. 27.5 INCHES 1899
9. 26.1 INCHES 1914
10. 26.0 INCHES 1958
10. 26.0 INCHES 1988
LOOKING AT THE SEASONAL SNOWFALL IT STANDS AT 64.8 INCHES. NORMAL
FOR THE ENTIRE WINTER SEASON IS 59.1 INCHES.
SO HOW DOES THIS WINTER COMPARE TO RECENT WINTERS FOR ALBANY...
2012-13: 51.4 INCHES
2011-12: 23.3 INCHES
2010-11: 87.2 INCHES
2009-10: 45.4 INCHES
2008-09: 52.6 INCHES
2007-08: 61.1 INCHES
2006-07: 45.9 INCHES
2005-06: 30.2 INCHES
2004-05: 75.9 INCHES
2003-04: 65.1 INCHES
2002-03: 105.4 INCHES
2001-02: 47.4 INCHES
2000-01: 77.1 INCHES
ALBANY EXTREMES:
SNOWIEST 1970-71 WITH 112.5 INCHES
LEAST 1912-13 WITH ONLY 13.8 INCHES
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM EST
FRIDAY FOR NYZ033-039>043-048>050-082>084.
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 PM EST
THIS EVENING FOR NYZ032-038-047-051>054.
MA...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 PM EST
THIS EVENING FOR MAZ001-025.
VT...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM EST
FRIDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...BGM/JPV/WASULA
SHORT TERM...BGM
LONG TERM...KL
AVIATION...JPV
HYDROLOGY...KL/BGM/WASULA
CLIMATE...NWS ALY STAFF
AREA FORECAST DISCUSSION
NWS ALBANY NY
1230 PM EST THU FEB 20 2014
.SYNOPSIS...
A STRONG LOW PRESSURE SYSTEM WILL NORTHWARD INTO THE WESTERN GREAT
LAKES REGION TONIGHT. ITS ASSOCIATED WARM FRONT WILL PROVIDE A
PERIOD OF WINTRY PRECIPITATION FOR MANY AREAS TONIGHT.
HOWEVER...WARMER AIR WILL EVENTUALLY LIFT NORTHWARD TO RESULT IN
MOSTLY RAIN FRIDAY ALONG WITH A SLIGHT CHANCE FOR THUNDERSTORMS. A
COLD FRONT PASSES ACROSS THE AREA FRIDAY AFTERNOON WITH A RETURN TO
COOLER WEATHER FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM EST...HIGH PRESSURE CONTINUES TO MOVE EAST OF THE MID
ATLANTIC AND DELMARVA REGION EARLY THIS AFTERNOON. A WARM FRONT
CONTINUES TO LIFT NORTH/NORTHEAST FROM THE OHIO VALLEY AND LOWER
MID ATLANTIC REGION. SUNSHINE...IS GIVING WAY TO PARTIAL SUNSHINE
WITH INCREASING MID AND HIGH CLOUDS FROM THE WEST. THESE CLOUDS
ARE MOVING IN QUICK WHICH WILL SLOW DOWN THE WARMING...WHICH HAS
BEEN SUBSTANTIAL TODAY WITH LOWER TO MID 40S IN MANY OF THE VALLEY
AREAS. SOME SLIGHT TWEAK WERE MADE WITH THE MAX TEMP AND TRENDS.
CLOUDS WERE ALSO RETOOLED BASED ON THE SATELLITE PICTURE. THE
LATEST HRRR 3-KM REF PRODUCT IS ALSO A TAD BIT SLOWER THIS RUN
WITH THE STRONG ISENTROPIC LIFT ON THE 285/290K SFC NOT ARRIVING
UNTIL ABOUT 23Z-01Z. THE POPS WERE RETRENDED SLIGHTLY FAVORING A
RAIN/SNOW TRANSITION ESPECIALLY FROM THE CAPITAL REGION NORTH. THE
INTENSITY OF THE PCPN...AND THE ACTUAL WET BULB COOLING WILL
DETERMINE HOW FAR SOUTH THE HEAVIER PCPN/SNOW WILL BE. THE
HEADLINES WILL REMAIN FOR NOW...AS FAR SOUTH AS THE CAPITAL
REGION.
TONIGHT...H2O VAPOR IMAGERY REVEALS A VERY POTENT SHORT WAVE
EJECTING OUT ONTO THE CENTRAL PLAINS. MEANWHILE...A SUBTROPICAL
PLUME OF MOISTURE EXTENDED FROM THE CENTRAL PACIFIC...ACROSS BAJA
CALIFORNIA AND ONTO THE SOUTHERN PLAINS AND MID WEST. PWATS WITHIN
THIS DEEPER MOISTURE WAS BETWEEN 1-3 STANDARD DEVIATIONS ABOVE
NORMAL AS NCEP MODEL SUITE AND SHORT TERM GUIDANCE /RUC13-HRRR/
SUGGEST A RAPID INCREASE IN MOISTURE TRANSPORT EVOLVING THROUGH
THE DAY TODAY. LOW LEVEL JET GREATER THAN 50KTS IS ALSO EXPECTED
TO DEVELOP TO ASSIST WITH THE MOISTURE TRANSPORT NORTHWARD INTO
OUR CWA BY LATE THIS AFTERNOON. THERMAL PROFILES FROM BUFR
PROFILES SUGGEST A RAIN/SNOW LINE SOMEWHERE ALONG OR JUST SOUTH OF
I90 PER WET BULB ZERO.
CROSS SECTIONS TONIGHT POINT TOWARD ANOTHER IMPRESSIVE 2D FGEN
ENHANCEMENTS AS PER CSTAR RESEARCH SUGGESTS BANDED STRUCTURES TO
THE PRECIP DEVELOPING OVER THE REGION. PER THE NCEP MODEL
SUITE...THIS BAND WILL MIGRATE FROM SOUTH TO NORTH THROUGH THIS
EVENING AND MAY LINGER ACROSS PORTIONS OF THE ADIRONDACKS
OVERNIGHT. IN ADDITION...INCREASING SOUTHERLY FLOW FAVORS UPSLOPE
CONDITIONS FURTHER ENHANCING THE PRECIP AMOUNTS. AS FOR
PRECIP...THERMAL PROFILES ARE TRICKY. WITHIN THE VICINITY OF I90
CORRIDOR...THE INITIAL ONSET OF PRECIP WILL LIKELY BE A RAIN/SNOW
TO SNOW THIS EARLY EVENING WITH A TRANSITION TO SLEET AND PERHAPS
A PERIOD OF FREEZING RAIN THROUGH THE LATER EVENING HOURS AS
WARMER AIR ALOFT /H850/ CLIMBS ABOVE FREEZING. DUE TO THE ENHANCE
2D FGEN AND A LAYER OF NEGATIVE EPV JUST ABOVE THIS LAYER WITH >20
UBAR/SEC OMEGA...THIS POINTS TOWARD THE POTENTIAL FOR AN MODERATE
TO HEAVY BAND OF PRECIP LIFTING NORTHWARD WITH A QUICK
ACCUMULATING SNOW THIS EVENING. THE BETTER CHANCE FOR A QUICK
ACCUMULATING SNOWFALL WILL BE NORTH OF I90 WHERE UP TO 4 INCHES
COULD FALL IN A SHORT PERIOD OF TIME. DUE TO THE COMPLEX THERMAL
PROFILES AND THE HIGH POTENTIAL FOR BANDED PRECIP STRUCTURES...WE
WILL HOIST ADVISORIES FOR THE NORTHERN 2/3RDS OF THE CWA. SOUTHERN
PORTIONS APPEAR TO REMAIN ABOVE FREEZING FOR MOST OF THE PRECIP TO
FALL AS RAIN. AS THE WARMER AIR CONTINUES ALOFT...THE PRECIP TO
THE NORTH OF I90 MIXING WITH SLEET AND FREEZING RAIN. THOSE LOWER
VALLEY LOCATIONS WITHIN THE MOUNTAINS COULD EXPERIENCE A PERIOD OF
ACCUMULATING ICE WITH CURRENT PROJECTIONS UP TO TWO TENTHS OF AN
INCH IN A FEW LOCATIONS WITH MOST AREA EXPECTED TO REMAIN BELOW
THAT VALUE.
TEMPERATURES WILL FOLLOW A NON-DIURNAL CURVE THE NEXT 24 HOURS AS
STRENGTHENING WARM ADVECTION UNFOLDS AS WARM FRONT LIFTS NORTHWARD.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
LOW LEVEL JET PER THE GEFS/SREF ENSEMBLES WILL RANGE BETWEEN 2-3
STANDARD DEVIATIONS ABOVE NORMAL ACROSS THE REGION ALONG WITH
THOSE HIGH PWATS FOR THIS TIME OF THE YEAR. AS TEMPERATURES
CONTINUE TO CLIMB ABOVE FREEZING...THIS WILL REDUCE THE WINTRY
MIXTURE TO MAINLY RAIN. THE FORECAST AREA IS EXPECTED TO BE WELL
WITHIN THE WARM SECTOR AS H850 TEMPS CLIMB TOWARD +8C. THIS WILL
INCREASE THE SNOW MELT ALONG WITH DEWPOINTS CLIMBING ABOVE
FREEZING. PATCHY FOG IS EXPECTED ALONG WITH THE INCREASE IN
RAINFALL POTENTIAL. IN FACT...FORECAST SOUNDINGS SUGGEST LIFTING
PARCELS ABOVE THE BOUNDARY LAYER YIELDS THE POSSIBILITY FOR
THUNDERSTORMS AS SHOWALTERS DROP BELOW 0C. IN COORDINATION WITH
SPC...WE WILL INTRODUCE A SLIGHT CHANCE FOR THUNDER ACROSS THE
ENTIRE REGION. RAINFALL RATES ALONG THE STRONG BAROCLINIC FRONTAL
ZONE COULD BE RATHER HIGH FOR THIS TIME OF THE YEAR. AT THIS
TIME...NO HYDRO RELATED HEADLINES BUT COULD SEE SOME URBAN AND
SMALL STREAM ISSUES AS PERHAPS ICE JAMS DUE TO BREAK UP /MORE
BELOW IN THE HYDRO SECTION/. TEMPERATURES FOR MOST OF THE AREA ARE
EXPECTED TO BE WELL INTO 40S. THE STRONG WINDS ALOFT SHOULD REMAIN
ABOVE THE BOUNDARY LAYER WITH NOT MUCH MIXING EXPECTED.
FROPA IS EXPECTED AROUND THE 21Z TIME FRAME. THE H850 TEMPS PLUNGE
FROM AROUND +8C TO AROUND -6C IN ABOUT 6HRS. THERE COULD A PERIOD
OF RAIN MIXING WITH A LITTLE SNOW IN THE WAKE OF THE FROPA BUT
ACCUMULATIONS ARE NOT EXPECTED FOR MOST OF THE REGION. WHERE SOME
LIGHT ACCUMULATIONS ARE POSSIBLE WILL BE ACROSS THE ADIRONDACKS AS
AN UPPER LEVEL IMPULSE ROTATES ACROSS THIS REGION AROUND THE
PERIPHERY OF THE DEEP UPPER LOW NEAR JAMES BAY AND SOME LAKE
ONTARIO CONTRIBUTION. TEMPERATURES WILL DIP BACK BELOW FREEZING
FRIDAY NIGHT AS SOME BLACK ICE COULD FORM ON THOSE UNTREATED
SURFACES.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
MUCH OF THE PERIOD WILL FEATURE THE RETURN OF BELOW NORMAL
TEMPERATURES...ALONG WITH A FEW POSSIBLE EPISODES OF SNOW SHOWERS
AND/OR LIGHT SNOW...AS MID/UPPER LEVEL HEIGHTS FALL CONSIDERABLY
ACROSS SOUTHERN AND EASTERN CANADA...INTO THE CENTRAL AND EASTERN
U.S.
HERE ARE SOME MORE SPECIFIC DETAILS...
SAT-SAT NT...IN THE WAKE OF FRIDAY/S FRONTAL SYSTEM...A BROAD
SOUTHWEST FLOW IN THE MID AND UPPER LEVELS OF THE TROPOSPHERE WILL
ALLOW FOR ONLY GRADUAL LOW LEVEL COOLING TO OCCUR. THEREFORE...WE
EXPECT TEMPS TO REMAIN ABOVE SEASONAL LEVELS ON SAT...RISING INTO
THE 40S IN MOST VALLEY AREAS...AND 30S ACROSS HIGHER ELEVATIONS. IT
IS POSSIBLE THAT SOME PORTIONS OF THE MID HUDSON VALLEY AND LOWER
ELEVATIONS IN NW CT APPROACH 50 WITH SUNSHINE AND A DOWNSLOPING
WESTERLY LOW LEVEL FLOW. IN THE AFTERNOON...A WEAK UPPER LEVEL
IMPULSE MAY BRING SOME CLOUDS...AND PERHAPS SOME LIGHT SHOWERS OF
RAIN/SNOW IN THE AFTERNOON/EVENING FOR CENTRAL AND NORTHERN AREAS.
FOR SAT NT...TEMPS WILL FALL INTO THE 20S IN MOST AREAS...WITH SOME
TEENS ACROSS THE WESTERN ADIRONDACKS...WHERE SOME SNOW SHOWERS WILL
ALSO BE POSSIBLE.
SUN-MON NT...THE TREND TOWARD COLDER TEMPS WILL CONTINUE...WITH
SUNDAY MAX TEMPS REACHING THE MID 30S TO LOWER 40S IN VALLEYS...AND
20S TO LOWER 30S ACROSS HIGHER ELEVATIONS...WHILE MONDAY MAXES ONLY
REACH THE 20S IN VALLEYS...AND TEENS ACROSS HIGHER ELEVATIONS. SOME
SNOW SHOWERS/FLURRIES WILL BE POSSIBLE ACROSS CENTRAL AND NORTHERN
AREAS LATE SUN INTO MONDAY NT. TEMPS MON NT WILL FALL INTO THE
SINGLE DIGITS IN MOST AREAS.
TUE-WED...MODEL UNCERTAINTY INCREASES WITH REGARD TO THE HANDLING OF
POTENTIAL FAST MOVING UPPER LEVEL IMPULSES DURING THIS TIME PERIOD.
THE 00Z/20 ECMWF HINTS AT ONE POSSIBLE IMPULSE AFFECTING THE REGION
TUE...ESP CENTRAL AND SOUTHERN AREAS...WITH SOME LIGHT SNOW...WHILE
THIS SIGNAL IS SOMEWHAT WEAKER IN THE 00Z/20 GFS AND GEFS. WILL
TREND TOWARD THE ECMWF SOLUTION...WITH SLIGHT CHC POPS ACROSS
CENTRAL AND SOUTHERN AREAS FOR SNOW SHOWERS...ALONG WITH SOME CHC
POPS ACROSS THE WESTERN ADIRONDACKS. BOTH THE 00Z/20 ECMWF/GFS AND
GEFS HINT AT ANOTHER IMPULSE PASSING MAINLY SOUTH OF THE REGION ON
WED...ALTHOUGH THE GEFS ARE A LITTLE FURTHER NORTH WITH POSSIBLE
MEASURABLE PRECIPITATION. WILL THEREFORE INDICATE LOW CHC POPS FOR
LIGHT SNOW ON WED. OTHERWISE...TEMPS WILL REMAIN WELL BELOW NORMAL
DURING THIS PERIOD...WITH DAYTIME MAXES MAINLY IN THE 20S FOR
VALLEYS...AND TEENS FOR HIGHER ELEVATIONS...AND OVERNIGHT MIN TEMPS
MAINLY IN THE SINGLE DIGITS TO LOWER TEENS.
&&
.AVIATION /17Z THURSDAY THROUGH MONDAY/...
AFTER ANY FOG/LOW CLOUDS LIFT BETWEEN 12Z-14Z/THU...VFR CONDITIONS
ARE EXPECTED THROUGH AT LEAST 22Z/THU. THEREAFTER...A STRONG WARM
FRONT WILL APPROACH FROM THE SOUTHWEST. A BAND OF MODERATE TO
LOCALLY HEAVY PRECIPITATION IS EXPECTED TO DEVELOP AHEAD OF THIS
FRONT...IMPACTING KGFL THE LONGEST...AND SOMEWHAT SHORTER AT
KALB/KPSF...AND LEAST AT KPOU. P-TYPE INITIALLY SHOULD BE MAINLY
SNOW AT KGFL...AND A MIX OF SNOW/SLEET AND SOME RAIN AT KALB AND
KPSF. AS MILDER AIR ALOFT MOVES IN...SNOW SHOULD CHANGE TO A MIX OF
FREEZING RAIN AND SLEET AFTER ROUGHLY 03Z/FRI AT KGFL. AT KALB AND
KPSF...AFTER A SNOW/SLEET/RAIN MIX...P-TYPE SHOULD BECOME MAINLY
RAIN WITH PERHAPS SOME OCCASIONAL SLEET AFTER 03Z/FRI. CONDITIONS
WILL GENERALLY BE IFR IN AREAS WHERE SNOW AND SLEET INITIALLY
OCCUR...AND MVFR WITHIN ANY RAIN. HOWEVER...LATER TONIGHT...CIGS
AND VSBYS WILL LIKELY DIP INTO THE IFR/LIFR RANGE IN ALL AREAS.
WEST TO NORTHWEST WINDS AT 5-10 KT WILL BECOME LIGHT/VARIABLE AS A
HIGH PRESSURE RIDGE SLIDES ACROSS THE TAF SITES. AS THE RIDGE SHIFTS
EAST OF THE TAF SITES...WINDS WILL BECOME SOUTHEAST TO SOUTH AT 5-10
KT LATER THIS AFTERNOON INTO TONIGHT...ALTHOUGH MAY BACK INTO THE
NORTHEAST AT KGFL AFTER SUNSET. WINDS THU NT SHOULD BE MAINLY FROM
THE E TO NE...AT LESS THAN 5 KT...EXCEPT SOUTH TO SOUTHEAST AT KALB
AT 5-10 KT.
OUTLOOK...
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY RA...FG.
FRIDAY: HIGH OPERATIONAL IMPACT. DEFINITE RA...FG.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
THE SNOW DEPTHS ACROSS EAST CENTRAL NEW YORK AND ADJACENT WESTERN
NEW ENGLAND ARE GENERALLY FROM 1 TO 3 FEET.
MODERATING TEMPERATURES REMAIN IN THE FORECAST WHICH WILL REACH
ITS PEAK DURING FRIDAY. SNOW MELT WILL INITIALLY BE SMALL AT FIRST
WITH A GRADUAL INCREASE DURING FRIDAY.
RAINFALL TOTALS TONIGHT AND FRIDAY ARE FORECAST TO GENERALLY BE
IN THE HALF AN INCH TO ONE INCH RANGE BASED ON THE LATEST
NERFC/WPC GUIDANCE. THE HIGHER TOTALS ARE EXPECTED ACROSS THE SRN
DACKS REGION...WHERE ISOLATED AMOUNTS TO AN INCH AND A HALF ARE
POSSIBLE. THERE WILL BE A PERIOD OF WINTRY MIXTURE AT THE ONSET
AND THROUGH MOST OF TONIGHT WITH A TRANSITION TO RAIN FROM
SOUTHWEST TO NORTHEAST. WE EXPECT MUCH OF THE RAINFALL WILL SOAK
INTO THE DEEP SNOW PACK.
PER THE LATEST MMEFS...THERE IS A SMALL POTENTIAL FOR FLOODING
ACROSS THE WESTERN MOHAWK VALLEY BUT DUE TO ICE IN PLACE...FOCUS
WILL BE THE ICE JAM POTENTIAL. HOWEVER...ACCUMULATING TEMPERATURES
REMAINING ABOVE FREEZING WILL BE MINIMAL WHICH SHOULD KEEP THINGS
IN CHECK. NEVERTHELESS...IT IS NOT ZERO AS WE WILL CONTINUE TO
HIGHLIGHT WITHING THE HWO.
COLDER TEMPERATURES ARE EXPECTED FRIDAY NIGHT...AND LATER IN THE
WEEK. AN ISOLATED OR LOCALIZED ICE JAM THREAT WILL CONTINUE TO BE
MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.CLIMATE...
THE MONTHLY SNOWFALL TOTAL FOR FEBRUARY AT THE ALBANY INTERNATIONAL
AIRPORT IS AT 27.7 INCHES THROUGH THE 19TH. IT IS THE 7TH
SNOWIEST FEBRUARY ON RECORD.
TOP 10 SNOWIEST FEBRUARYS ALBANY
1. 40.7 INCHES 1893
2. 34.5 INCHES 1962
3. 32.3 INCHES 1926
4. 31.7 INCHES 1950
5. 30.1 INCHES 2011
6. 28.6 INCHES 1993
7. 27.7 INCHES 2014
8. 27.5 INCHES 1899
9. 26.1 INCHES 1914
10. 26.0 INCHES 1958
10. 26.0 INCHES 1988
LOOKING AT THE SEASONAL SNOWFALL IT STANDS AT 64.8 INCHES. NORMAL
FOR THE ENTIRE WINTER SEASON IS 59.1 INCHES.
SO HOW DOES THIS WINTER COMPARE TO RECENT WINTERS FOR ALBANY...
2012-13: 51.4 INCHES
2011-12: 23.3 INCHES
2010-11: 87.2 INCHES
2009-10: 45.4 INCHES
2008-09: 52.6 INCHES
2007-08: 61.1 INCHES
2006-07: 45.9 INCHES
2005-06: 30.2 INCHES
2004-05: 75.9 INCHES
2003-04: 65.1 INCHES
2002-03: 105.4 INCHES
2001-02: 47.4 INCHES
2000-01: 77.1 INCHES
ALBANY EXTREMES:
SNOWIEST 1970-71 WITH 112.5 INCHES
LEAST 1912-13 WITH ONLY 13.8 INCHES
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM EST
FRIDAY FOR NYZ033-039>043-048>050-082>084.
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 PM EST
THIS EVENING FOR NYZ032-038-047-051>054.
MA...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 PM EST
THIS EVENING FOR MAZ001-025.
VT...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 11 AM EST
FRIDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...BGM/WASULA
NEAR TERM...BGM/JPV/WASULA
SHORT TERM...BGM
LONG TERM...KL
AVIATION...KL
HYDROLOGY...KL/BGM/WASULA
CLIMATE...
LONG TERM FORECAST DISCUSSION...
/ISSUED 415 AM EST THU FEB 20 2014/
BEHIND FRIDAY`S COLD FRONT... ECMWF AND GFS SHOW A COOL DOME OF
HIGH PRESSURE BUILDING OVER THE FORECAST AREA FRIDAY NIGHT... AND
SHOULD DOMINATE THROUGH SATURDAY. THE RIDGE DOES SLIP EAST AND
ESTABLISH A LIGHT/WARM SOUTHERLY WIND FLOW BY SATURDAY AFTERNOON.
THIS WILL ALLOW A NICE WARM-UP INTO THE 60S ON SATURDAY.
BOTH MODELS SHOW A WEAK UPPER DISTURBANCE IN THE NEARLY ZONAL FLOW
ALOFT TRAVERSING THE AREAS AND INTERACTING WITH AN OLD FRONTAL
BOUNDARY ACROSS SOUTH GEORGIA. THIS SPREADS SOME ISOLATED TO LOW
SCATTERED SHOWERS INTO THE FORECAST AREA ON SUNDAY...WITH THE GREATER
RAIN CHANCES EXPECTED ACROSS PARTS OF CENTRAL GEORGIA ON SUNDAY.
STILL GOOD AGREEMENT ON A REINFORCING COLD FRONT PUSHING ACROSS
THE AREA SUNDAY NIGHT... WITH A DRY FORECAST ON TAP FOR MONDAY.
BOTH MODELS SHOW AN ACTIVE NEARLY ZONAL FLOW ALOFT INTERACTING
WITH A WEAK FRONTAL BOUNDARY MEANDERING ACROSS THE AREA ON TUESDAY
AND WEDNESDAY. STILL SOME UNCERTAINTY ON JUST WHERE BEST RAIN
CHANCES WILL SET UP... SO WILL JUST SHOW A SLIGHT CHANCE OF
SHOWERS ALL ZONES FOR NOW. LACK OF INSTABILITY AND WIND SHEAR WILL
WARRANT JUST WORDING FOR SHOWERS WITH NO THUNDERSTORMS EXPECTED AT
THIS TIME.
39
&&
AVIATION...
18Z UPDATE...
SOME LIGHT SHOWERS ARE POSSIBLE THIS AFTERNOON BUT SHOULD REMAIN
NORTH OF THE TAF SITES. IT ISNT UNTIL OVERNIGHT THAT THE TSRA/SHRA
WILL MOVE THROUGH THE TAF SITES. WINDS THIS AFTERNOON WILL WAIVER
AROUND 180 BUT WITH WINDS ABOVE THE SFC BEING SW...THINK THEY WILL
FAVOR THE SW SIDE OF 180. CIGS ARE VRB ACROSS THE SITES...BUT
CONTINUE TO IMPROVE THIS AFTERNOON. WILL SEE A DECREASE TO LOW MVFR/IFR
OVERNIGHT.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM CONFIDENCE ON CIGS...VSBYS...AND TIMING OF PRECIP. LOW CONFIDENCE
ON WIND DIRECTION GIVEN THE VARIABILITY AROUND 180.
11
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 51 62 34 67 / 90 100 5 10
ATLANTA 48 58 38 64 / 100 80 5 10
BLAIRSVILLE 46 54 30 62 / 100 70 5 10
CARTERSVILLE 48 59 31 66 / 100 60 5 10
COLUMBUS 52 60 38 67 / 100 100 5 10
GAINESVILLE 48 60 36 66 / 100 100 5 10
MACON 56 63 33 68 / 70 90 5 10
ROME 48 60 29 65 / 100 40 5 10
PEACHTREE CITY 50 60 29 67 / 100 90 5 10
VIDALIA 61 66 44 68 / 30 100 10 10
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....20
AVIATION...11
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
212 PM EST THU FEB 20 2014
.SYNOPSIS...
WARM TEMPERATURES CONTINUE ONCE AGAIN TODAY AHEAD OF AN
APPROACHING COLD FRONT. THIS STRONG COLD FRONT WILL CROSS THE
AREA FRIDAY BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. HIGH
PRESSURE AND DRIER AIR WILL BUILD INTO THE REGION FRIDAY EVENING.
&&
.NEAR TERM /THROUGH TONIGHT/...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE WESTERN ATLANTIC.
WE ARE EXPECTING NEAR RECORD HIGH TEMPERATURES UNDER SUNNY SKIES
THIS AFTERNOON. TEMPERATURES SHOULD PEAK IN THE MID 70S TO LOWER
80S.
LOW PRESSURE OVER THE CENTRAL PLAINS WILL LIFT NORTH TO THE
WESTERN GREAT LAKES TONIGHT. ITS ASSOCIATED COLD FRONT WILL CROSS
THE MS RIVER VALLEY THIS EVENING AND CROSS THE APPALACHIANS TOWARD
DAWN FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL
INCREASE LATE TONIGHT AS THIS STRONG COLD FRONT APPROACHES.
THE HRRR MODEL INDICATING FOG/STRATUS SPREADING INTO THE EASTERN
MIDLANDS FROM THE COAST LATE THIS EVENING. IF THIS OCCURS A DENSE
FOG ADVISORY MAY BE NEEDED. LOW TEMPERATURES TONIGHT WILL BE
AROUND 60.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
A STRONG COLD FRONT WILL BE JUST WEST OF THE FORECAST AREA BY
FRIDAY MORNING...AND IS EXPECTED TO RAPIDLY MOVE THROUGH THE CWA
FROM THE MORNING INTO THE EARLY AFTERNOON. BY THE AFTERNOON THE
FRONT WILL BE MOVE MOVING EAST TO THE COAST AND OFFSHORE FRIDAY
NIGHT. THERE REMAINS A POTENTIAL FOR THUNDERSTORMS AHEAD OF THE
FRONT...MAINLY DUE TO THE LOW-LEVEL WINDS AROUND 850MB AT 50 TO 55
KNOTS. OTHER CONCERN IS FOR DRIER AIR QUICKLY OVERTAKING THE MID
LEVELS BEHIND THE FRONT. ONE NEGATIVE IN REGARDS TO STORMS IS THAT
THE MODELS ARE SHOWING MUCH OF THE STRONGER UPPER ENERGY LIFTING
NORTH OF THE AREA DURING THE MORNING. OVERALL CONCERN FOR SEVERE
POTENTIAL WITH FROPA IS STILL POSSIBLE AT THIS TIME BUT WILL
CONTINUE TO MONITOR.
HIGH TEMPERATURES WILL BE IN THE MID 60S FOR FRIDAY WITH TEMPERATURES
ONLY SLOWLY CLIMBING THROUGH THE MORNING AND THEN FALLING DURING THE
AFTERNOON. OVERNIGHT LOWS IN THE UPPER 30S TO THE LOWER 40S FRIDAY
NIGHT.
HIGH PRESSURE WILL BUILD IN OVER THE AREA FOR SATURDAY. COOLER WITH
HIGHS IN THE MIDDLE TO 60S. OVERNIGHT LOWS MAINLY IN THE LOWER TO
MIDDLE 40S SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
VERY FEW CHANGES IN THE EXTENDED FORECAST. NEAR ZONAL FLOW ALOFT
WITH WEAK IMPULSES WILL BE THE RULE SUNDAY THROUGH WEDNESDAY...WITH
A BROAD UPPER TROUGH DEVELOPING OVER THE SOUTHERN PLAINS BY
THURSDAY. OVERALL...WITH THE WEAK IMPULSES IN THE ZONAL
FLOW...EXPECT A SLIGHT CHANCE OF RAIN FOR PORTIONS OF THE LONG TERM
WITH SOME LOW CONFIDENCE WITH THE TIMING ISSUES. TEMPERATURES
THROUGH THE LONG TERM WILL BE NEAR TO SLIGHTLY ABOVE NORMAL.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
HIGH CONFIDENCE FOR VFR CONDITIONS ALL TERMINALS THROUGH AROUND
02Z.
GUSTY SOUTHERLY WINDS EXPECTED THIS AFTERNOON. WINDS TO DIMINISH
AROUND 23Z. THE HRRR MODEL...AND THE SREF MODEL...INDICATING
FOG/STRATUS SPREADING INTO THE EASTERN MIDLAND FROM THE COAST LATE
THIS EVENING. THUS HAVE INDICATED IFR CIGS DEVELOPING AT
OGB/CUB/CAE DURING THE 03Z-05Z TIME-FRAME. MVFR OR LOWER LOWER
CONDITIONS TO DEVELOP AT AGS/DNL AFTER 06Z AS LOW LEVEL MOISTURE
INCREASES AHEAD OF AN APPROACHING COLD FRONT.
GUIDANCE SUGGESTS VSBYS WILL ALSO GO DOWN INTO THE IFR RANGE BUT
NOT AS CONFIDENT GIVEN MODERATE SURFACE WINDS AS THE PRESSURE
GRADIENT INCREASES AHEAD OF THE FRONT. COULD SEE ISOLATED SHOWERS
AROUND THE TERMINALS 08Z-11Z... WITH WIDESPREAD SHOWER AND
THUNDERSTORMS CROSSING THE TAF SITES IN THE 12-16Z TIME-FRAME
AHEAD OF A STRONG COLD FRONT.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE SUNDAY NIGHT AND
AGAIN TUESDAY AS A COUPLE FRONTAL BOUNDARIES CROSS THE AREA.
&&
.CLIMATE...
HIGH TEMPERATURES THIS AFTERNOON APPROACHING DAILY RECORD VALUES.
AT CAE...RECORD HIGH FOR FEB 20TH IS 83 SET IN 1991.
AT AGS...RECORD HIGH FOR FEB 20TH IS 82 SET IN 1991.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
203 PM EST THU FEB 20 2014
.SYNOPSIS...
WARM TEMPERATURES CONTINUE ONCE AGAIN TODAY AHEAD OF AN
APPROACHING COLD FRONT. THIS STRONG COLD FRONT WILL CROSS THE
AREA FRIDAY BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS. HIGH
PRESSURE AND DRIER AIR WILL BUILD INTO THE REGION FRIDAY EVENING.
&&
.NEAR TERM /THROUGH TONIGHT/...
SURFACE HIGH PRESSURE WILL REMAIN OVER THE WESTERN ATLANTIC.
WE ARE EXPECTING NEAR RECORD HIGH TEMPERATURES UNDER SUNNY SKIES
THIS AFTERNOON. TEMPERATURES SHOULD PEAK IN THE MID 70S TO LOWER
80S.
LOW PRESSURE OVER THE CENTRAL PLAINS WILL LIFT NORTH TO THE
WESTERN GREAT LAKES TONIGHT. ITS ASSOCIATED COLD FRONT WILL CROSS
THE MS RIVER VALLEY THIS EVENING AND CROSS THE APPALACHIANS TOWARD
DAWN FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL
INCREASE LATE TONIGHT AS THIS STRONG COLD FRONT APPROACHES.
THE HRRR MODEL INDICATING FOG/STRATUS SPREADING INTO THE EASTERN
MIDLANDS FROM THE COAST LATE THIS EVENING. IF THIS OCCURS A DENSE
FOG ADVISORY MAY BE NEEDED. LOW TEMPERATURES TONIGHT WILL BE
AROUND 60.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
LOW PRESSURE WILL MOVE INTO THE WESTERN GREAT LAKES THURSDAY NIGHT
AS AN ASSOCIATED COLD FRONT PUSHES ACROSS THE GULF STATES THURSDAY
NIGHT AND INTO THE FORECAST AREA FRIDAY MORNING AND INTO THE
AFTERNOON. BY THE AFTERNOON THE FRONT WILL MOVE TO THE COAST AND
OFFSHORE FRIDAY NIGHT. POTENTIAL FOR THUNDERSTORMS CONTINUES TO
SLOWLY INCREASE FOR COLD FRONT PASSAGE WITH CURRENT CONCERN
SURROUNDING SHEAR WITH WINDS AROUND 850MB NEARING 50 KNOTS. OTHER
CONCERN IS FOR DRIER AIR QUICKLY OVERTAKING THE MID LEVELS BEHIND
THE FRONT. OVERALL CONCERN FOR SEVERE POTENTIAL WITH FROPA REMAINS
LOW AT THIS TIME BUT WILL CONTINUE TO MONITOR. LOW TEMPERATURES
THURSDAY NIGHT MAINLY AROUND 60. HIGH TEMPERATURES WILL BE IN THE
MID 60S TO AROUND 70 FOR FRIDAY...WITH OVERNIGHT LOWS IN THE UPPER
30S TO THE LOWER 40S FRIDAY NIGHT.
HIGH PRESSURE WILL BUILD IN OVER THE AREA FOR SATURDAY. COOLER WITH
HIGHS IN THE LOWER TO MIDDLE 60S. OVERNIGHT LOWS IN THE LOWER TO
MIDDLE 40S SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
MODELS THROUGH THE LONG TERM SEEM TO BE IN GOOD AGREEMENT WITH THE
SYNOPTIC PATTERN...HOWEVER HAVE SIGNIFICANT DIFFERENCES IN TIMING OF
MOISTURE ACROSS THE REGION. UPPER PATTERN FOR MUCH OF THE LONG TERM
REMAINS MOSTLY ZONAL WITH SOME SHORT WAVE ACTIVITY APPROACHING FROM
THE WEST. GFS MAY BE A BIT TOO AGGRESSIVE WITH INCREASED MOISTURE SO
WILL LEAN TOWARDS A DRIER SOLUTION FOR SUNDAY. WILL KEEP SLIGHT
CHANCE POPS MONDAY THROUGH TUESDAY AS A FRONTAL SYSTEM REMAINS JUST
SOUTH OF THE AREA. MAINLY DRY FOR WEDNESDAY. THE UNCERTAINTY
CONTINUES THROUGH THE REMAINDER OF THE LONG TERM RESULTING IN LOW
CONFIDENCE AND ONLY MINOR ADJUSTMENTS TO MONDAY THROUGH WEDNESDAY.
TEMPERATURES THROUGH THE LONG TERM WILL BE NEAR TO SLIGHTLY ABOVE
NORMAL.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
HIGH CONFIDENCE FOR VFR CONDITIONS ALL TERMINALS THROUGH AROUND
02Z.
GUSTY SOUTHERLY WINDS EXPECTED THIS AFTERNOON. WINDS TO DIMINISH
AROUND 23Z. THE HRRR MODEL...AND THE SREF MODEL...INDICATING
FOG/STRATUS SPREADING INTO THE EASTERN MIDLAND FROM THE COAST LATE
THIS EVENING. THUS HAVE INDICATED IFR CIGS DEVELOPING AT
OGB/CUB/CAE DURING THE 03Z-05Z TIME-FRAME. MVFR OR LOWER LOWER
CONDITIONS TO DEVELOP AT AGS/DNL AFTER 06Z AS LOW LEVEL MOISTURE
INCREASES AHEAD OF AN APPROACHING COLD FRONT.
GUIDANCE SUGGESTS VSBYS WILL ALSO GO DOWN INTO THE IFR RANGE BUT
NOT AS CONFIDENT GIVEN MODERATE SURFACE WINDS AS THE PRESSURE
GRADIENT INCREASES AHEAD OF THE FRONT. COULD SEE ISOLATED SHOWERS
AROUND THE TERMINALS 08Z-11Z... WITH WIDESPREAD SHOWER AND
THUNDERSTORMS CROSSING THE TAF SITES IN THE 12-16Z TIME-FRAME
AHEAD OF A STRONG COLD FRONT.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE SUNDAY NIGHT AND
AGAIN TUESDAY AS A COUPLE FRONTAL BOUNDARIES CROSS THE AREA.
&&
.CLIMATE...
HIGH TEMPERATURES THIS AFTERNOON APPROACHING DAILY RECORD VALUES.
AT CAE...RECORD HIGH FOR FEB 20TH IS 83 SET IN 1991.
AT AGS...RECORD HIGH FOR FEB 20TH IS 82 SET IN 1991.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
115 PM CST THU FEB 20 2014
.DISCUSSION...
1130 AM CST
UPDATED FORECAST GRIDS FOR THE AFTERNOON REFLECT HIGHER POPS AND
QPF BASED ON LATEST RADAR TRENDS AND PRONOUNCED LOW LEVEL MOISTURE
CONVERGENCE ACROSS THE AREA. AN INITIAL LINE OF SHOWERS AND STORMS
MOVED THROUGH EARLY THIS MORNING AND A SECOND BATCH IS CROSSING
THE AREA AROUND MIDDAY. EXPECT THE CURRENT ACTIVITY TO LINGER INTO
THE EARLY AFTERNOON ACROSS THE NORTHERN TWO THIRDS OF THE FORECAST
AREA. TWO BOUNDARIES HAVE YET TO CROSS THE AREA...THE WARM FRONT
LIFTING OUT OF SOUTHEAST IOWA AND CENTRAL ILLINOIS...AND THE COLD
FRONT ACROSS WESTERN MISSOURI. WITH EITHER OR BOTH OF THESE
BOUNDARIES THERE IS A GOOD CHANCE FOR ANOTHER LINE OF SHOWERS AND
POSSIBLE THUNDERSTORMS LATER THIS AFTERNOON.
THE ARRIVAL OF THE WARM FRONTAL BOUNDARY THIS AFTERNOON WILL
USHER IN VERY MOIST AIR WITH DEWPOINTS IN THE 50S. VSBYS AS LOW AS
1/4 TO 1/2 MILE ARE BEING REPORTED NEAR THIS FEATURE IN CENTRAL
ILLINOIS BUT FORTUNATELY THESE VALUES DO NOT APPEAR TO BE
WIDESPREAD. A DENSE FOG ADVISORY MAY YET BE REQUIRED THIS
AFTERNOON BUT FOR NOW WILL JUST PLAN TO MONITOR THE SITUATION FOR
WIDESPREAD DETERIORATING CONDITIONS.
THE ONSET OF STRONG WINDS TOWARD LATE AFTERNOON OR EVENING STILL
LOOKS ON TRACK. DIRECTION WOULD START AS SOUTHERLY AND THEN BECOME
SOUTHWESTERLY OVERNIGHT. GUSTS EXCEEDING 50 MPH ARE BEING
REPORTED IN SW MISSOURI.
LENNING
//PREV DISCUSSION...
534 AM CST
HAVE GOTTEN SEVERAL REPORTS OF THUNDERSNOW OUT OF THE NORTHERN
CHICAGO SUBURBS. ACARS SOUNDINGS OUT OF ORD WOULD SUPPORT ALL
RAIN...BUT WOULD SUSPECT THE STRONG LIFT WITH THE CONVECTION IS
LOCALLY COOLING THE COLUMN ENOUGH FOR A SWITCH OVER TO WHAT HAS
BEEN REPORTED AS A HEAVY VERY WET SNOW. COOP IN JUST NW OF
WOODSTOCK PICKED UP 1.3 INCHES OF SLUSH. AS THE HEAVIER
REFLECTIVITY SHIFTS EAST AND WAA CONTINUES WOULD EXPECT THE
THREAT OF +TSSN TO END SHORTLY. HAVE ISSUED A NOWCAST TO COVER
THIS THREAT THAT SHOULD (HOPEFULLY) BE ENDING IN THE NEXT 30-60
MINS.
IZZI
//PREV DISCUSSION...
324 AM CST
POTENTIALLY HIGH IMPACT...MULTIFACETED CYCLONE WILL CONTINUE TO
IMPACT THE REGION THROUGH TONIGHT. POTENTIAL EXISTS FOR HEAVY
RAINFALL (MAINLY THROUGH MID MORNING)...THUNDERSTORMS...A SQUALL
LINE AROUND 00Z THIS EVENING...THEN NON-CONVECTIVE STRONG/LOCALLY
DAMAGING WINDS THIS EVENING.
VERY STRONG LOW LEVEL JET (NEARLY 60KT @ 850MB) CONTINUES TO DRIVE
UNSEASONABLY MOIST AIR NORTHWARD INTO A LOOSELY ORGANIZED MCS
ONGOING OVER EASTERN IA/NORTHERN IL EARLY THIS MORNING. BEEN A
REMARKABLE AMOUNT OF CG LIGHTNING FOR THIS TIME OF YEAR WITH THIS
COMPLEX WITH WSR-88D DATA INDICATING A LOT OF POTENTIAL
GRAUPEL/SMALL HAIL ALOFT WITH THE HIGH DBZ ECHOS...THOUGH SOME OF
THAT COULD ALSO BE WET SNOW FLAKES MELTING.
MCS WILL TRAVERSE THE REGION EARLY THIS MORNING WITH SOME BACK
BUILDING POSSIBLY RESULTING IN PRECIP LINGERING INTO THE 15-18Z TIME
RANGE...BUT THE MAJORITY OF THE HEAVIEST PRECIP LIKELY DONE BEFORE
15Z. SHORT RANGE CONVECTIVE ALLOWING MODELS CONTINUE TO SUGGEST THAT
LOCALIZED RAINFALL TOTALS UP TO AROUND AN INCH ARE POSSIBLE WITH
THIS MCS...PARTICULARLY IN THE VICINITY OF THE I-80 CORRIDOR AND
THIS SEEMS TO BE SUPPORTED BY REGIONAL RADAR TRENDS. NOTE: USE THE
HOURLY AND STORM TOTAL PRECIP PRODUCTS FROM OUR RADAR THIS MORNING
WITH CAUTION...BRIGHT BANDING/GRAUPEL/SMALL HAIL ARE RESULTING IN
INFLATED VALUES BASED ON UPSTREAM SFC OBS.
JUST GET A REPORT OF SOME SPOTTY WET SNOW BETWEEN ELGIN IN RFD BY
WTVO MORNING MET ON HER WAY TO WORK...SO DEFINITELY SEEING SOME
SPOTTY WET SNOW/SLEET/GRAUPEL...BUT ANTICIPATE MOST OF THAT TO
QUICKY TRANSITION TO ALL RAIN AS WARM AIR ADVECTION CONTINUES. TEMPS
ARE MOSTLY IN THE MID 30S AND ALMOST ALL THE ROAD SFC TEMP DATA
SENSORS WE HAVE ACCESS TO SHOW PAVEMENT TEMPS ABOVE FREEZING...SO
ITS LOOKING LIKE WE WILL LARGELY DODGE A BULLET WITH ANY SNOW/ICE
PROBLEMS BRIEF AND CONFINED MOSTLY TO MORE RURAL AREAS OF NC IL.
THE INITIAL SHORTWAVE HELPING ORGANIZING THIS MORNING CONVECTION
SHOULD SHIFT EAST ALONG WITH THE NOSE OF THE LOW LEVEL JET...SO
SHOULD SEE WIDESPREAD AND HEAVIER PRECIP END FROM MID-LATE MORNING
THROUGH MUCH OF THE AFTERNOON. SHOULD STILL BE SOME SCTD/OCNL
SHOWERS IN THE CONTINUED WAA REGIME AS WARM FRONT INCHES NORTH.
DESPITE THE END OF THE HEAVIER MORE WIDESPREAD RAIN BEFORE
18Z...PLAN TO HANG ON TO FLOOD WATCH THRU 21Z TO COVER RUN OFF AND
SNOW MELT PROBLEMS THAT COULD LINGER INTO THE AFTERNOON AFTER THE
HEAVIER RAIN ENDS.
STILL LOOKS LIKELY THAT A STRONGLY FORCED LOW TOPPED LINE OF
CONVECTION WITH LITTLE/NO LIGHTNING ACCOMPANYING THE COLD FRONT WILL
SWEEP ACROSS THE CWA BETWEEN ABOUT 2230Z AND 0130Z. SFC BASED
INSTABILITY IS LIKELY TO BE LACKING...BUT THE EXTREMELY STRONG
FORCING WITH THE VERY DYNAMIC/EXPLOSIVELY DEEPENING SYSTEM STILL
LEAVES ME QUITE CONCERNED ABOUT WIND GUSTS OVER 60 MPH IN SPOTS WITH
THIS SQUALL LINE. IN THE WAKE OF THE SQUALL LINE VERY STRONG
PRESSURE GRADIENT AND IMPRESSIVE PRESSURE RISES WITH MODEST COLD AIR
ADVECTION/STEEP LOW LEVEL LAPSE RATES SHOULD ALLOW FOR A PERIOD OF
VERY STRONG WINDS THIS EVENING. TO PUT INTO PERSPECTIVE JUST HOW
IMPRESSIVE THIS STORM IS...A COLLEGUE AT WPC WHO HAS BEEN DOING WORK
WITH MINIMUM/MAXIMUM MONTHLY PRESSURE TOOK A QUICK LOOK AND INITIAL
FINDINGS INDICATE THAT THIS STORM WILL LIKELY BE THE DEEPEST
FEBRUARY LOW PRESSURE IN THIS REGION SINCE 1902!
HAVE OPTED TO UPGRADE THE HIGH WIND WATCH TO A WARNING FOR THIS
EVENING. NOT CONFIDENT THAT WE`LL MEET STRICT 58MPH GUST CRITERIA
EVERYWHERE...BUT SEEMS LIKELY AT LEAST SOME LOCATIONS WILL GUST TO
AROUND 60 MPH. THE FRINGE BENEFIT IS THAT THIS WARNING SHOULD COVER
ANY BRIEF CONVECTIVE 60+ MPH WIND GUSTS WITH THE LINE OF STRONGLY
FORCED SHOWERS ALONG THE COLD FRONT THIS EVENING AND ALLEVIATE
HAVING TO POTENTIALLY ISSUE SEVERE THUNDERSTORM WARNINGS FOR
LIGHTNING-LESS CONVECTION IF IT DOES END UP PRODUCING SEVERE GUSTS.
VERY STRONG WINDS WILL LIKELY CONTINUE BEYOND THE 05Z SCHEDULED
EXPIRATION TIME OF THE HIGH WIND WARNING...BUT LIKELY MORE IN THE
45-55 MPH RANGE AND FULLY ANTICIPATE THE HIGH WIND WARNING BEING
RAMPED DOWN TO A WIND ADVISORY THIS EVENING.
STRONG WINDS AND SEASONABLY COLD AIR ARE ON TAP FOR FRIDAY AS THE
MASSIVE THEN OCCLUDED CYCLONE FILLS AND GRADUALLY SPINS ITSELF DOWN.
MODELS ARE STILL HAVING FITS HANDLING WEAK SUBTLE WAVES TRACKING
ALONG THE SOUTHERN PERIPHERY OF THE HUDSON LOW...WITH GEM/GFS
HINTING AT SOME LIGHT ACCUMULATING SNOW OVER CENTRAL IL AND OUR
SOUTHERN CWA FRIDAY NIGHT...THEN NAM IS BY ITSELF ALL AMPED UP ABOUT
AN ACCUMULATING SNOW SAT NIGHT (AGAIN SOUTHERN HALF OF CWA)...THEN
ECMWF IS HITTING SNOW CHANCES HARD LATER MONDAY. CERTAINLY PLAUSIBLE
THAT WE COULD POTENTIALLY SEE ONE OR MORE BOUTS OF SOME ACCUMULATING
SNOW INTO EARLY NEXT WEEK...BUT UNTIL WE START TO GET A STRONGER
MORE CONSISTENT SIGNAL IN MODEL GUIDANCE IT IS HARD TO GO VERY HIGH
WITH POPS.
MEDIUM RANGE MODELS CONTINUE TO PAINT AN UNSEASONABLY COLD PICTURE
HEADING INTO NEXT WEEK. ECMWF/GFS BOTH FORECAST H8 TEMPS TO GET INTO
THE 3+ STANDARD DEVIATION BELOW AVERAGE TERRITORY...WHICH IF IT WERE
TO VERIFY COULD RESULT IN TEMPS THREATENING RECORDS BY THE MIDDLE OF
NEXT WEEK. CERTAINLY PLENTY OF TIME FOR MODELS TO BACK ON OF
MAGNITUDE OF THE COLD SOME...BUT THE GENERAL IDEA OF MUCH BELOW
AVERAGE TEMPS HEADING INTO THE LAST WEEK OF METEOROLOGICAL WINTER
LOOKS VERY LIKELY. SOME INDICATIONS ARE THAT THERE COULD BE ANOTHER
ACCUMULATING SNOW THREAT IN/NEAR THE AREA IN ADVANCE OF THE STRONGER
PUSH OF ARCTIC AIR TOWARD THE MIDDLE OF NEXT WEEK...BUT WITH SO MUCH
VARIABILITY OF THE EXACT MODEL DETAILS...THERE IS LITTLE TO HANG
YOUR HAT ON AT THIS TIME.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 19Z...
* 1/2 TO 1/4 SM VISIBILITIES IN FOG LIKELY THROUGH LATE
AFTERNOON/EARLY EVENING.
* IFR TO LIFR CIGS THROUGH THE AFTERNOON.
* MORE THUNDERSTORMS POSSIBLE LATER THIS AFTERNOON INTO THE EARLY
EVENING.
* VERY STRONG WEST-SOUTHWEST WINDS SETTING UP EARLY THIS EVENING
WITH GUSTS AS HIGH AS 50 KT OUT OF THE SOUTHWEST.
* PERIOD OF LIGHT SNOW LATE TONIGHT INTO FRIDAY MORNING.
KJB
//DISCUSSION...UPDATED 19Z...
ALREADY MADE AN UPDATE TO THE 18 UTC TAFS BASED ON OBS TO THE
SOUTH. IT APPEARS MUCH MORE LIKELY THAT DENSE FOG WITH VIS OF 1/2
TO 1/4 SM WILL DEVELOP ACROSS THE TERMINALS. IN FACT THE LATEST
OBSERVATION OUT OF MDW INDICATES THEY ARE ALREADY THERE...SO ORD
AND DPA WILL BE IN IT WITHIN THE NEXT COUPLE HOURS. IT APPEARS
THAT THIS FOG WILL LAST FOR SEVERAL HOURS THIS AFTERNOON...LIKELY
UNTIL THE LINE OF THUNDERSTORMS CURRENTLY ACROSS MISSOURI GETS
HERE LATER THIS AFTERNOON AROUND 22-23 UTC.
KB
//DISCUSSION...UPDATED 18Z...
A VERY POWERFUL STORM SYSTEM WILL IMPACT THE REGION THROUGH MUCH OF
THE PERIOD. THIS WILL RESULT IN PERIODS OF RAIN AND EMBEDDED
THUNDERSTORMS THIS AFTERNOON...ALONG WITH IFR TO LIFR CIGS AND
IFR TO LIFR VISIBILITIES. A SURFACE WARM FRONT...ASSOCIATED WITH
THE STORM SYSTEM...WILL LIFT NORTHWARD ACROSS THE TAF SITES BY MID
TO LATE AFTERNOON. DEW POINTS ARE EXPECTED TO SPIKE WELL INTO THE
40S IN THE WAKE OF THIS FRONT AS MOISTURE SURGES NORTHWARD. THIS
COULD SET THE STAGE FOR A FEW HOUR PERIOD OF DENSE FOG ACROSS THE
AREA LATER THIS AFTERNOON AND EARLY EVENING AS THESE HIGH DEW
POINTS MOVE OVER THE SNOW PACK...ESSENTIALLY SATURATING THE LOW
LEVELS.
THE RAIN CURRENTLY MOVING ACROSS THE AREA DOES HAVE A FEW EMBEDDED
LIGHTENING STRIKES. IN SPITE OF THIS...I LEFT THE MENTION OF TSRA OUT
OF THE NEW TAF FOR THE NEXT FEW HOURS...MENTIONING ONLY PREVAILING
SHOWERS OF RAIN. I EXPECT THIS ACTIVITY TO CONTINUE ACROSS THE
REGION FOR THE NEXT COUPLE HOURS...INTO THE EARLY AFTERNOON HOURS.
THEREAFTER...SOME FOG IS LIKELY TO REDUCE VISIBILITIES THROUGH THE
REST OF THE AFTERNOON. IT IS POSSIBLE FOR VISIBILITIES TO DROP WELL
BELOW A MILE IN FOG LATER THIS AFTERNOON...AS THE HIGHER DEW POINTS
STREAM NORTHWARD. HOWEVER...CONFIDENCE IN HOW DENSE THE FOG WILL
BECOME IS STILL SOMEWHAT LOW. THEREFORE I HAVE REMAINED
OPTIMISTIC...ONLY MENTIONING VIS DOWN AROUND 3/4 SM IN THE GOING
TAFS.
A STRONG COLD FRONT IS SET TO PUSH ACROSS THE AREA EARLY THIS
EVENING. THIS COULD RESULT IN ANOTHER VERY QUICK HIT OF SHOWERS AND
THUNDERSTORMS ALONG AND AHEAD OF THIS FRONT. HOWEVER...THE MAIN
STORY WILL BE THE VERY STRONG WINDS SETTING UP RIGHT BEHIND THIS
FRONT. WINDS WILL QUICKLY SHIFT OUT OF THE SOUTHWEST AND BECOME VERY
GUSTY AFTER 02 TO 03 UTC THIS EVENING. IN FACT...GUSTS COULD BE
CLOSE TO 50 KT FOR A COUPLE HOUR PERIOD THIS EVENING...BEFORE THEY
EASE SOME OVERNIGHT. THESE STRONG GUSTY WINDS WILL LIKELY REMAIN
GUSTY UP AROUND 36 KT THROUGH FRIDAY AS THE SURFACE LOW CONTINUES TO
STRENGTHEN AS IT MOVES NORTHWARD ACROSS THE UPPER GREAT LAKES
REGION.
ALTHOUGH VISIBILITIES AND CIGS SHOULD IMPROVE FOLLOWING THE FRONTAL
PASSAGE THIS EVENING...MOISTURE RAPPING AROUND THE LARGE STRONG AREA
OF LOW PRESSURE COULD RESULT IN A PERIOD OF SNOW ACROSS THE AREA
VERY LATE TONIGHT INTO FRIDAY MORNING. THIS COULD LEAD TO LOWER VIS
IN SNOW AND BLSN...WITH SOME MINOR ACCUMULATIONS POSSIBLE.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 19Z...
* HIGH FOR PERIODS OF FOG WITH VIS 1/2 SM OR LESS THROUGH THE REST
OF THE AFTERNOON.
* MEDIUM WITH RAIN/THUNDERSTORM TIMING LATER THIS AFTERNOON AND
EARLY EVENING.
* MEDIUM TO HIGH WITH CEILINGS.
* MEDIUM TO HIGH WITH WIND DIRECTION/SPEED.
* MEDIUM ON PERIOD OF SNOW LATE TONIGHT INTO EARLY FRIDAY.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...VFR.
SUNDAY...VFR.
MONDAY...SLIGHT CHANCE OF LIGHT SNOW...OTHERWISE VFR.
TUESDAY...VFR.
WEDNESDAY...VFR.
RODRIGUEZ
&&
.MARINE...
448 AM CST
VERY STRONG WINDS EXPECTED OVER THE ENTIRE LAKE WHICH INCLUDES THE
NEARSHORE AND OPEN WATERS LATER THIS AFTERNOON INTO FRIDAY.
AS APPROACHING LOW PRESSURE OVER THE CENTRAL PLAINS TAKES SHAPE
THIS MORNING...LIGHTER SOUTHEAST WINDS CURRENTLY BEING OBSERVED
OVER THE LAKE. ALTHOUGH AS THIS LOW APPROACHES AND STRENGTHENS
TODAY...WINDS WILL STEADILY INCREASE WITH GALES LIKELY BY LATE
THIS AFTERNOON. GALES WILL THEN CONTINUE INCREASING WITH THIS
STRENGTHENING LOW THIS EVENING...WHILE TURNING MORE SOUTHERLY.
WITH COLDER AIR MOVING OVER THE LAKE THIS EVENING...WINDS WILL
STRENGTHEN TO STORM FORCE AS THEY TURN TO THE SOUTHWEST. STORM
FORCE WINDS WILL THEN BE OBSERVED OVER THE OPEN WATERS THROUGH
FRIDAY AFTERNOON...WITH SOME UNCERTAINTY AS TO THE DURATION OF THE
STORM FORCE WINDS OVER THE NEARSHORE. CURRENTLY HAVE STORM FORCE
WINDS AND THE WARNING FOR TONIGHT...BUT ITS POSSIBLE THIS MAY NEED
TO BE EXTENDED IN THE NEARSHORE. GALES WILL THEN BE LIKELY INTO
FRIDAY EVENING FOR THE OPEN WATERS...AND THROUGH FRIDAY FOR THE
NEARSHORE.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLOOD WATCH...ILZ010-ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-
ILZ021-ILZ022-ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 3 PM
THURSDAY.
HIGH WIND WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...5 PM THURSDAY TO 11 PM
THURSDAY.
IN...FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 3 PM
THURSDAY.
HIGH WIND WARNING...INZ001-INZ002-INZ010-INZ011-INZ019...5 PM
THURSDAY TO 11 PM THURSDAY.
LM...GALE WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL MIDNIGHT FRIDAY.
STORM WARNING...LMZ080-LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-LMZ868-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...MIDNIGHT FRIDAY TO 3
PM FRIDAY.
GALE WARNING...NEARSHORE WATERS UNTIL 9
PM THURSDAY.
STORM WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745...9 PM
THURSDAY TO 4 AM FRIDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
115 PM CST Thu Feb 20 2014
.MESOSCALE DISCUSSION...
ISSUED 114 PM CST Thu Feb 20 2014
Warm front getting a substantial push northward and is starting to
come into Bloomington. Still have mid to upper 30s to the north,
but widespread upper 50s to near 60 south. Dew points of 50 degrees
now as far north as Lincoln.
Line of thunderstorms rapidly filling in across central Missouri,
in an area where some clearing helped destabilize the atmosphere,
with surface based CAPE`s around 1000 J/kg per SPC mesoanalysis
page. HRRR has been doing a good job with the development and
placement of this line. HRRR and extrapolation tool on AWIPS
indicate the line should move into the western CWA between 2:30
and 3 pm and reach the eastern counties between 4-5 pm. Still
several inches of snow cover across the north which will help
stabilize things, but Springfield has lost 4 inches of snow depth
just this morning and much of what`s left will be gone very soon,
helping with the instability. RAP model showing MUCAPE`s around
800 J/kg across the central and southeast CWA by mid afternoon,
helping to sustain the storms. VAD wind profile off our radar
showing 55 knots at the 925 mb level, so plenty of wind in the low
levels for the storms to try and bring downward toward the
surface.
Geelhart
&&
.AVIATION...
ISSUED 1155 AM CST Thu Feb 20 2014
Warm front has lifted just north of KSPI/KDEC/KCMI, shifting winds
back around to the south and gusting to around 25-30 knots, while
east winds around 10 knots continue further north. Should see the
front continue to lift northward over the next couple of hours.
Have had some areas of dense fog primarily north of the front, as
a significant increase in low level moisture moves in with the
front, but this is likely to fade out in the next couple hours.
Line of convection starting to form in central Missouri, and will
move east through central Illinois mid to late afternoon. Have
included about a 3 hour period of VCTS at each TAF site for now,
and will update later to narrow down the time frame once the line
becomes more mature. A cold front will pass by shortly behind the
line of storms, switching winds to the west. Still looks like
gusts of 35-45 knots will be likely this evening, as impressive
pressure rises spread across the state in the wake of a deepening
low pressure passage. Wraparound snow showers may spread as far
south as KPIA/KBMI after 06Z. Have maintained the MVFR conditions
through the night, before improvement early Friday morning. Winds
by Friday morning not quite as high, but still gusting in the 30
knot vicinity.
Geelhart
&&
.PREV DISCUSSION...
ISSUED 1010 AM CST Thu Feb 20 2014
Warm frontal boundary is waffling along the I-72 corridor this
morning, with 40s and 50s south and 30s to the north. Most of the
precipitation over the last few hours has been on the cold side of
the storm, especially across the far northwest CWA where
thunderstorms have produced some pea size hail as well. That
particular area has received 1 to 1.5 inches of rain since
yesterday evening. The front extends to parent low pressure along
the Kansas/Missouri border.
Focus remains with the winds, precipitation and temperature
trends. Have sent some zone/grid updates recently to reflect a
period of lower PoP`s into early afternoon, and as the front lifts
northward, before the main activity develops toward mid to late
afternoon. Latest Day1 convective outlook pushed the slight risk
back northwest to around Shelbyville, reflective of the slower
arrival of the cold front, with damaging winds still the primary
threat. The cold front should push to around I-57 by sunset and
exit the state shortly after that. The post-frontal period is when
the winds will really start ramping up, as the low experiences
substantial and rapid intensification this afternoon as it moves
into southwest Wisconsin. 3-hour pressure rises of around 10 mb
will push through Missouri late this afternoon and across the CWA
early this evening. Wind gusts outside the storms still look to
reach around 45 mph by late afternoon and 50-60 mph this evening.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 3 AM CST Friday FOR ILZ056-061>063-066>068-
071>073.
HIGH WIND WARNING until 3 AM CST Friday FOR ILZ027>031-036>038-
040>055-057.
FLOOD WATCH until 6 PM CST this evening FOR ILZ027>031-036>038-
040>053.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1103 AM MST THU FEB 20 2014
.UPDATE...
ISSUED AT 1103 AM MST THU FEB 20 2014
BASED ON LATEST MODEL DATA AS WELL AS UPSTREAM OBSERVATIONS IN
WESTERN NEBRASKA...HAVE ISSUED A HIGH WIND WARNING FOR COUNTIES
ALONG/EAST OF A HITCHCOCK TO RAWLINS AND SHERIDAN COUNTY LINE FOR
THIS AFTERNOON.
LATEST HRRR HAS BEGUN TO SHOW AN AREA OF 50 KT WINDS MOVING
ACROSS THE AFOREMENTIONED AREA THIS AFTERNOON. IN ADDITION THE
LATEST RUC HAS ALSO INCREASED THE WIND SPEEDS AT THE TOP OF THE
BOUNDARY LAYER FOR THIS AFTERNOON AS WELL AS EXPANDED THE AREA OF
HIGHEST WIND GUSTS. WIND GUSTS AROUND 60 MPH CAN BE EXPECTED IN
THE NEXT HOUR OR TWO...WITH WIND GUSTS DECLINING DURING THE LATE
AFTERNOON. DUE TO TEMPERATURES BEING ABOVE FREEZING DO NOT
ANTICIPATE MUCH IF ANY BLOWING SNOW.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT.)
ISSUED AT 236 AM MST THU FEB 20 2014
SNOW AND BLOWING SNOW WITH AREAS OF REDUCED VISIBILITY CONTINUE
TO MOVE ACROSS MAINLY THE EASTERN PORTION OF THE FORECAST AREA
THIS MORNING WHILE SNOW APPEARS TO BE ENDING FROM WEST TO EAST
ACROSS FAR EASTERN COLORADO. AM RELUCTANT TO TRIM OFF THE WESTERN
PORTION OF THE WINTER WEATHER ADVISORY TOO EARLY AS WINDS ARE
STILL STRONG ENOUGH TO PRODUCE AREAS OF BLOWING SNOW AND REDUCED
VISIBILITIES.
EXPECT SNOW TO CONTINUE TO MOVE EAST OUT OF THE FORECAST AREA
QUICKLY THIS MORNING AND WILL CONTINUE TO EVALUATE THE POSSIBLE
NEED FOR EXPANSION OF THE ADVISORY IN TIME ACROSS THE EAST THIS
MORNING AND THE POSSIBLE TRIMMING OF THE ADVISORY AREAS ACROSS
THE WEST.
EXPECT THE WINDS TO DECREASE SOMEWHAT THIS MORNING FOLLOWING
SUNRISE AND TO RE-INTENSIFY THROUGH THE MORNING. WILL LEAVE THE
WIND ADVISORY INTACT ACROSS THE ENTIRE FORECAST AREA AS A RESULT.
NORTHWEST WINDS DECREASE RAPIDLY LATE THIS AFTERNOON AND
EVENING AND TURN MORE WESTERLY OVERNIGHT TONIGHT.
WARMER TEMPERATURES ARE EXPECTED ON FRIDAY WITH COOLER
TEMPERATURES SATURDAY WITH A CHANCE OF LIGHT SNOW MOVING INTO THE
AREA FROM THE NORTH ON SATURDAY NIGHT AS THE JET STREAM POSITIONED
ACROSS THE NORTHERN PLAINS BRINGS WEAK IMPULSES EAST OF THE
ROCKIES.
.LONG TERM...(SUNDAY THROUGH NEXT THURSDAY)
ISSUED AT 1206 AM MST THU FEB 20 2014
A LONGWAVE TROUGH WILL BE OVER THE NORTHERN PLAINS AND GREAT LAKES
WITH A SERIES OF SHORTWAVE TROUGHS MOVING THROUGH. THIS WILL
RESULT IN NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES AND
OCCASIONAL CHANCES FOR LIGHT SNOW. THESE SYSTEMS ARE ALL VERY WEAK
AND PRODUCE AN INCH OR LESS OF SNOW. HIGH TEMPERATURES WILL
GENERALLY BE IN THE 30S AND 40S WITH LOWS IN THE TEENS AND 20S. AT
THE VERY END OF THE LONG TERM PERIOD...COLDER AIR MAY BE TAPPED BY
A SOUTHERN STREAM SYSTEM WHICH COULD RESULT IN MUCH BELOW NORMAL
TEMPERATURES FOR THE END OF NEXT WEEK AND BETTER CHANCES OF SNOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1013 AM MST THU FEB 20 2014
VFR CONDITIONS FORECAST FOR THE 12Z TAFS. MAIN ISSUE WILL BE THE
WIND SPEEDS FOR THIS AFTERNOON. EXPECT THE NORTHWEST WINDS TO
INCREASE AS THE MAIN UPPER LEVEL TROUGH APPROACHES THE AREA
THROUGH MID AFTERNOON. KMCK COULD SEE A FEW GUSTS NEAR/AT 50 KTS
DURING THE EARLY TO MID AFTERNOON. OTHERWISE WINDS WILL DECLINE
DURING THE LATE AFTERNOON...BECOMING LIGHT TO BREEZY TONIGHT. DO
NOT ANTICIPATE MUCH BLOWING SNOW SINCE TEMPERATURES HAVE WARMED
ABOVE FREEZING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ001-013-014-027>029-041-042.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR KSZ002>004-015-
016.
CO...WIND ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR COZ090>092.
NE...WIND ADVISORY UNTIL 5 PM MST THIS AFTERNOON FOR NEZ079.
HIGH WIND WARNING UNTIL 6 PM CST THIS EVENING FOR NEZ080-081.
&&
$$
UPDATE...JTL
SHORT TERM...LOCKHART
LONG TERM...024
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
344 PM CST THU FEB 20 2014
.SHORT TERM...
BIGGEST IMPACT OVER THE FORECAST PERIOD WILL BE OVER THE NEXT 12 TO
15 HOURS. AN UPPER LEVEL TROUGH IS CURRENTLY MOVING ACROSS THE
NORTHERN AND CENTRAL PLAINS OF THE UNITED STATES. THE TIGHTEST CURL
AT THE BASE OF THE LOW IS NOW STARTING TO CURL NORTHEAST TOWARDS THE
UPPER MISSISSIPPI VALLEY. THE ASSOCIATED COLD FRONT IS NOW MOVING
SOUTHEAST OVER EASTERN TEXAS AND JUST ENTERING THE EXTREME
NORTHWESTERN LOUISIANA PARISHES. LATEST RADAR IMAGERY SHOWS A LINE
OF THUNDERSTORMS HAS DEVELOPED ALONG AND AHEAD OF THE LEADING EDGE OF
THE COLD FRONT. MORE LOCALLY...SHOWERS ARE BEGINNING TO INCREASE IN
COVERAGE OVER MOST OF THE CWA. MODELS SHOW THIS TREND CONTINUING
THROUGH THE REST OF THE AFTERNOON. MODEL SOUNDINGS INDICATE THAT
ELEVATED INSTABILITY DOES EXIST OVER THE AREA RIGHT NOW WITH A
SLIGHTLY WARM NOSE JUST ABOVE 700MB. THIS WILL ERODE OVER THE NEXT
FEW HOURS WHICH COULD ALLOW FOR A A FEW STORMS TO INTENSIFY AND
LIKELY START PRODUCING THUNDER. THE NCEP WRF WAS THE MOST AGGRESSIVE
WITH MORE DISCRETE CELLS BEING DEPICTED ON IT. LOOKS TO BE THE
OUTLIAR OF MESO AND MEDIUM RANGE MODELS. THE MAIN PLAYER THIS
EVENING SHOULD BE STORMS ALONG AND JUST AHEAD OF THE COLD FRONT AS
IT MARCHES THROUGH THE FORECAST AREA WHERE DYNAMICAL LIFT WILL BE
THE GREATEST. IT WILL HAVE TO OVERCOME PRETTY SIGNIFICANTLY
DEVELOPING INVERSION WHILE COMING THROUGH. WITH THAT TYPE OF LIFT
AND FAIRLY STRONG WINDS THROUGH THE COLUMN...40 TO 50 KNOTS...THERE
WILL BE A THREAT FOR STRONG TO SEVERE WINDS ALONG THE FRONT. A
TORNADO IS NOT OUT OF THE QUESTION EITHER. THE RISK WILL BE GREATEST
IN SOUTHWEST MISSISSIPPI AND ADJACENT LOUISIANA PARISHES WITH
DECREASING THREAT TO THE SOUTH TOWARDS THE COAST. HRRR LOOKS TO
PRETTY SPOT ON IN TERMS OF INITIALIZATION OF THE CURRENT SQUALL
LINE POSITION AND MOVEMENT. CARRYING THAT OUT IN TIME BRINGS THE
LINE TO NWRN ZONES BY 02Z AND NEW ORLEANS METRO BY 06Z. SHOULD BE
FINISHING UP OVER LAND AREAS WITH STRONGER ACTIVITY BY AROUND 09Z
WITH LINGERING SHOWERS TRAILING BY A FEW HOURS. WOULD NOT BE
SURPRISED TO SEE A SEVERE WATCH PUT OUT FOR MUCH IF NOT ALL OF THE
AREA DURING THE EVENING AND EARLY MORNING HOURS. FOR THE POPS...KEPT
IT SIMPLE AND HAVE A PEAK OF 100 PCT ACROSS THE ENTIRE CWA. THE RAIN
SHOULD THEN TAPER OFF VERY QUICKLY CLOSING IN ON 12Z FRIDAY. BY THIS
POINT...ONLY EXTREME COASTAL LOCATIONS OF MS/LA AND SOUTHWARD SHOULD
HAVE ANY SHOWERS LEFT. THE COLD FRONT WILL CONTINUE SOUTH AND STALL
IN THE CENTRAL GULF OF MEXICO.
.LONG TERM...
ZONAL FLOW WILL RETURN ON SATURDAY AND REMAIN IN PLACE FOR A FEW
DAYS. BUILDING UPPER LEVEL RIDGE WELL TO THE SOUTH OF THE FORECAST
AREA WHICH WILL BRING THE PREVIOUS BOUNDARY BACK NORTH TO THE GULF
COAST. THIS WILL LIKELY BE THE FOCUS FOR SCATTERED SHOWERS AND
POSSIBLY A FEW THUNDERSTORMS BEGINNING ON SUNDAY. HAVE INCREASED
POPS QUITE A BIT ON SUNDAY TO BE MORE IN LINE WITH BOTH GFS AND
ECMWF QPF OUTPUTS. SLIGHTLY BELOW MEX BUT NOT BY MUCH. TEMPERATURES
WILL BE AT OR ABOVE NORMAL THROUGH THE ENTIRE FORECAST PERIOD.
MEFFER
&&
.MARINE...
STILL SEEING SOME LINGERING FOG OVER THE NEARSHORE WATERS NEAR AND
WEST OF THE MISSISSIPPI RIVER. WILL CONTINUE ADVISORY IN THOSE
COASTAL ZONES UNTIL MIDNIGHT. AFTER MIDNIGHT...WIND INCREASE SHOULD
MIX OUT FOG. WILL DROP ADVISORY OVER THE SOUNDS WITH FORECAST
ISSUANCE.
WILL HAVE A PERIOD OF EXERCISE CAUTION WINDS OVER PORTIONS OF THE
EASTERN OPEN WATERS OVERNIGHT...BUT WINDS ARE EXPECTED TO RELAX
SLIGHTLY DURING THE DAY ON THURSDAY. EXPECT SMALL CRAFT ADVISORY TO
BE NECESSARY ON FRIDAY BEHIND THE COLD FRONT...WITH WINDS EASING BY
EVENING. QUIET CONDITIONS EXPECTED BEYOND FRIDAY FOR THE WEEKEND. 35
&&
.AVIATION...
ONSHORE FLOW WELL ESTABLISHED TODAY WITH MVFR TO VFR CEILINGS
COMMON. GENERALLY SEEING LOWER DECK IN FL015-025 RANGE AND SECOND
DECK IN FL035-050 LAYER. THESE WILL OCCASIONALLY SCATTER OUT AND
THEN FILL BACK IN. HAVE MADE LITTLE CHANGE IN TIMING OF LINE OF
CONVECTION THAT IS JUST NOW BEGINNING TO DEVELOP NORTHWEST OF
SHREVEPORT...18Z TAF PACKAGE TIMING STILL REASONABLE. STILL
POTENTIAL FOR SEVERE WIND GUSTS WITH THIS LINE AS WELL AS TEMPORARY
IFR CEILINGS/VISIBILITIES. THE THUNDERSTORMS WILL BE NEAR OR JUST
AHEAD OF COLD FRONT WITH A QUICK SHIFT TO NORTHWEST WINDS BEHIND
FRONT. ANTICIPATE SEVERAL HOURS OF GUSTY WINDS BEHIND THE
FRONT...POSSIBLY GUSTING ABOVE 30 KNOTS DOWNWIND OF LAKE
PONTCHARTRAIN AT KMSY AND KNEW. CLOUDS EXPECTED TO CLEAR OUT RAPIDLY
BEHIND THE FRONT FRIDAY MORNING. 35
&&
.DECISION SUPPORT...
DSS CODE...BLUE WITH POSSIBLE UPGRADE THIS EVENING
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
MONITORING TSTM THREAT FOR THIS EVE/TONIGHT.
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 TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 45 66 37 70 / 100 10 0 0
BTR 47 67 42 73 / 100 10 0 0
ASD 51 67 38 69 / 100 10 0 0
MSY 53 66 47 68 / 100 10 0 0
GPT 51 66 40 66 / 100 10 0 0
PQL 50 68 37 69 / 100 20 0 0
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...SMALL CRAFT ADVISORY FROM MIDNIGHT FRIDAY TO NOON FRIDAY FOR THE
FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...COASTAL
WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER OUT 20 NM...COASTAL WATERS FROM
PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO 60 NM...COASTAL
WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20
NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA
RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM PORT FOURCHON
TO LOWER ATCHAFALAYA RIVER OUT 20 NM...COASTAL WATERS FROM
STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST
PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO
60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM...LAKE
BORGNE...LAKE PONTCHARTRAIN AND LAKE MAUREPAS...AND
MISSISSIPPI SOUND.
MS...NONE.
GM...SMALL CRAFT ADVISORY FROM MIDNIGHT FRIDAY TO NOON FRIDAY FOR THE
FOLLOWING ZONES: BRETON SOUND...CHANDELEUR SOUND...COASTAL
WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER OUT 20 NM...COASTAL WATERS FROM
PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO 60 NM...COASTAL
WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20
NM...COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA
RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM PORT FOURCHON
TO LOWER ATCHAFALAYA RIVER OUT 20 NM...COASTAL WATERS FROM
STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI
RIVER FROM 20 TO 60 NM...COASTAL WATERS FROM THE SOUTHWEST
PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO
60 NM...COASTAL WATERS FROM THE SOUTHWEST PASS OF THE
MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM...LAKE
BORGNE...LAKE PONTCHARTRAIN AND LAKE MAUREPAS...AND
MISSISSIPPI SOUND.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
427 PM EST THU FEB 20 2014
.SYNOPSIS...
A STALLED FRONTAL BOUNDARY ACROSS NORTH CAROLINA THIS EVENING WILL
LIFT NORTH AS A WARM FRONT LATER TONIGHT. A COLD FRONT CROSSES THE
MID ATLANTIC REGION ON FRIDAY. HIGH PRESSURE AND DRIER CONDITIONS
RETURN TO THE REGION DURING THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
VARIABLE CLOUDINESS TODAY WILL CONTINUE THROUGH TONIGHT. PLENTY OF
INSTABILITY IN THE FORM OF ACCAS CLOUDS (VIA VISIBLE SATELLITE
IMAGERY) CAN BE SEEN ALONG AND SOUTH OF A WARM FRONT STALLED
ACROSS NORTH CAROLINA LATE THIS AFTN. WILL NEED TO MONITOR THE
LOCATION/PROGRESS OF THE ACCAS INTO FAR WRN PORTIONS OF THE FA
LATE TONIGHT AS THE WARM FRONT LIFTS THROUGH THE REGION. HAVE
LIMITED POPS TO 10 PERCENT FOR THE PIEDMONT OVERNIGHT. GUSTY SOUTH
WINDS WILL DEVELOP AFTER MIDNIGHT BEHIND THE WARM FRONT AND
TEMPS/DEWPOINTS WILL START TO RISE. TEMPS SHOULD BOTTOM OUT
SHORTLY AFTER MIDNIGHT WITH LOWS IN THE LOWER 50S NORTH TO AROUND
60 DEGREES SOUTH. BY DAYBREAK...TEMPS SHOULD BE IN THE MID 50S
NORTH TO LOWER 60S SOUTH.
MEANWHILE...A STRONG LOW PRESSURE SYSTEM IN THE MIDWEST WILL TRACK
ALMOST DUE NORTH INTO THE GREAT LAKES REGION TONIGHT. THIS WILL
SHIFT THE UPPER LEVEL JET DYNAMICS INTO A MORE NORTH-TO-SOUTH
ORIENTATION AND WILL LIKELY DELAY THE ONSET OF PRECIPITATION BY A
FEW HOURS. THEREFORE PRECIP IS NOT EXPECTED TO MOVE INTO FAR WRN
PORTIONS OF THE FA UNTIL JUST AFTER DAYBREAK...HOWEVER ISENTROPIC
LIFT ADVECTING MOISTURE INTO THE PIEDMONT/CTRL VA MAY BE ENOUGH TO
SUPPORT SHOWERS JUST PRIOR TO SUNRISE. DUE TO SLOWER TIMING...HAVE
CUT BACK ON PRECIP CHANCES IN WRN AREAS TO 30 PERCENT PRE-DAWN TO
60-70 PERCENT JUST AFTER DAYBREAK.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
THE APPROACHING COLD FRONT WILL MOVE INTO THE WRN HALF OF THE CWA BY
MID-LATE MORNING AND THEN CROSS THE ERN HALF DURING THE AFTN...
PUSHING OFFSHORE DURING THE EVENING. THE BULK OF RAINFALL WILL
OCCUR RIGHT ALONG AND BEHIND THE FRONT WHICH WILL THEN CONTINUE
INTO FRIDAY EVENING BEFORE TAPERING OFF FROM WEST TO EAST. THERE
ARE SEVERAL PARAMETERS THAT WILL SUPPORT THUNDERSTORM DEVELOPMENT
ON FRIDAY DESPITE THE BEST DYNAMICS LYING WELL TO THE NORTH. THE
AREA WILL BE LOCATED ALONG THE RIGHT ENTRANCE REGION OF THE UPPER
LEVEL JET PLUS THERE IS DECENT MID LEVEL INSTABILITY (850-500 MB)
PRESENT...BOTH OF WHICH SUPPORT ENHANCED LIFT. 0-1 KM WIND SHEAR
PROFILES VEER FROM SOUTH TO SOUTHWEST AND THEN BECOME UNIDIRECTIONAL
FROM THE SOUTHWEST ABOVE 1 KM. THIS TYPE OF SHEAR PROFILE SUPPORTS
THUNDERSTORM LINE SEGMENTS AND ULTIMATELY A THREAT FOR GUSTY
THUNDERSTORM WINDS. AT THE SFC...SOUTH WINDS OF 15-20 MPH WILL
INCREASE IN STRENGTH AND BECOME GUSTY JUST AHEAD OF THE COLD
FRONTAL PASSAGE DURING THE LATE MORNING/EARLY AFTERNOON HOURS.
NON-THUNDERSTORM WIND GUSTS SHOULD AVERAGE AROUND 30-35 MPH.
MEANWHILE...THUNDERSTORM WIND GUSTS SHOULD RANGE FROM 30-50 MPH
WITH LOCALLY HIGHER GUSTS POSSIBLE. PWATS INCREASE TO 1.00-1.50
INCHES DURING THE DAY. THIS WILL CONTRIBUTE TO THE POTENTIAL FOR
MODERATE TO HEAVY RAINFALL AT TIMES...ESPECIALLY UNDER STRONGER
STORM CORES. STORM TOTAL QPF SHOULD AVERAGE 0.50 INCHES WITH
LOCALLY HIGHER AMOUNTS POSSIBLE DUE TO CONVECTION. TEMPERATURES
WILL BE TRICKY AND HIGHLY DEPENDENT ON THE FROPA TIMING. TRENDING
TWD A LATER ARRIVAL OF THE FRONT MEANS THAT TEMPS SHOULD TAKE ON
MORE OF A NORMAL DIURNAL TREND...BUT MAY PEAK BY LATE MORNING FAR
WRN AREAS AND BY EARLY AFTN FOR THE ERN HALF OF THE FA. HIGH TEMPS
RANGE FROM THE LOWER 60S NW/N TO UPPER 60S SE (AROUND 70 COASTAL
NE NC).
PRECIP COMES TO AN END FRIDAY EVENING AS THE FRONT PUSHES WELL
OFFSHORE. DECENT CLEARING AND WINDS BECOMING LIGHT WILL ALLOW TEMPS
TO DROP INTO THE LOW-MID 30S NW TO UPPER 30S SE BY SATURDAY MORNING.
HIGH PRESSURE AND DRIER CONDITIONS WILL PREVAIL SATURDAY INTO
SUNDAY. HIGHS WILL GENERALLY BE IN THE 60S SAT/SUN WITH LOWS SUNDAY
MORNING IN THE MID-UPPER 30S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH LATITUDES CONTINUE TO BE DOMINATED BY A DYNAMIC/HIGHLY
AMPLIFIED PATTERN THROUGH THE EXTENDED. QUASI-ZONAL FLOW OVER THE
CONUS TO BEGIN THE EXTENDED WILL AMPLIFY EARLY NEXT WEEK...
CHARACTERIZED BY A MEAN RIDGE IN THE WEST AND DEEPENING TROUGH IN
THE EAST. SHORTWAVE ENERGY IN THE NRN STREAM...ROUNDING THE BASE
OF A STRONG -2 TO -3 STD DEV UPPER LOW...WILL IMPACT THE NE INTO
THE MID- ATLANTIC THROUGH THE EXTENDED. HOWEVER...THESE WAVES ARE
TYPICALLY DIFFICULT TO TIME AND THERE REMAINS LARGE SPREADS IN
ENSEMBLE GUIDANCE AND DETERMINISTIC RUNS. THE FIRST WAVE WILL PUSH
A CLIPPER FRONT THROUGH THE REGION SUN NIGHT-MON MORNING. FRONTAL
PASSAGE ANTICIPATED TO BE DRY AS PROFILES SHOW LIMITED NRN STREAM
MOISTURE AND WLY FLOW. HIGH PRESSURE BUILDS IN BEHIND THE DEPARTING
FRONT MON. SPATIAL AND TIMING DIFFERENCES WITH THE SFC HIGH RESULT
IN A TRICKY TEMP FORECAST MON AS LOW LEVEL THICKNESSES BTWN
GFS/GEFS AND ECMWF ARE NEARLY 30 M. THE RESULT WOULD BE HIGHS IN
THE MID 40S OR MID 50S. PREFERRED AN ENSEMBLE/WPC APPROACH TO
SMOOTH OUT THE DIFFERENCES FOR THE TIME BEING WITH TEMPS SLIGHTLY
BELOW SEASONAL NORMS (HIGHS MID 40S NORTH TO LOW 50S SOUTH). THE
NEXT SHORTWAVE WILL TRAVERSE THE NE STATES TUES AS A WEAK SRN
STREAM WAVE DEVELOPS A LOW ALONG THE STALLED COLD FRONT OVER THE
GULF STATES. MODELS KEEP ANY MEASURABLE PRECIP SOUTH OF THE
REGION...WHICH MATCHES WELL WITH THE DEEPENING TROUGH OVER THE ERN
CONUS. WHILE CONDITIONS WILL REMAIN DRY TUES...DO ANTICIPATE
INCREASING CLOUDS THROUGH THE DAY. MORE POTENT SHORTWAVE DIGGING
OVER THE GREAT LAKES LATE TUES-TUES NIGHT AND INCREASING WINDS
ALOFT WILL DEVELOP A STRONGER WAVE ALONG THE FRONT OFF THE SE
COAST TUES NIGHT. LOW WILL LIFT OFF THE MID-ATLANTIC COAST WEDS
MORNING. HAVE OPTED TO MAINTAIN SLIGHT CHANCE POPS INLAND DUE TO
UNCERTAINTY (WHILE THE TREND MAY BE TO TAKE THEM OUT) BUT HAVE
INCREASED THE COAST TO LOW END CHANCE POPS TUES NIGHT-WEDS
MORNING. TEMPS MAY BE COLD ENOUGH FOR FROZEN PRECIP BUT CAA LOOKS
MARGINAL DUE TO NO STRONG HIGH PRESSURE TO THE NORTHWEST...SO HAVE
OPTED FOR RAIN OR SNOW WORDING AS FAR SOUTH AS CENTRAL VA. HIGH
PRESSURE BUILDS IN FROM THE WEST WED AFTERNOON THROUGH THE END OF
THE EXTENDED PERIOD...RESULTING IN MOSTLY CLEAR SKIES AND DRY/COOL
CONDITIONS.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
FRONTAL BOUNDARY WILL SLOWLY LIFT NORTH THROUGH THE AREA TONIGHT.
THE FRONT ALOFT IS GENERATING SOME CLOUDS THIS AFTERNOON AND
EVENING...ALL WILL BE VFR CIGS. NO PRECIPITATION IS EXPECTED. LATER
TONIGHT ALL MODELS SHOW MOISTURE ADVECTING NORTH OFF THE GULF
STREAM AND ACROSS THE AREA AT THE LOW LEVELS AFTER 06Z TONIGHT.
STILL NOT COMPLETELY CONVINCED ON THIS AS THE SREF ONLY DEPICTS IT
FOR KRIC AND KSBY. HOWEVER ALL BUFKIT SOUNDINGS FROM THE GFS NAM
AND RAP SHOW IT AT ALL THE SITES. SO DEVELOPED IFR CIGS AFTER 06Z
TONIGHT. MODELS ARE SLOW TO BREAK THESE CLOUDS FRIDAY MORNING SO
ONLY SLOWLY RAISE CIGS TO MVFR DURING THE MORNING. COLD FRONT WILL
BE APPROACHING KRIC BY THE END OF THE PERIOD AND BRING SHOWERS
INTO RIC AFTER 15Z AND KPHF BY 17Z. THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG THE LEADING EDGE OF THE FRONT AS IT MOVES THROUGH
THE AREA. EXPECT CIGS AND POTENTIALLY VSBY TO BECOME IFR WITH THESE
SHOWERS DUE TO MODERATE TO HEAVY RAINFALL COMBINED WITH GUSTY
SOUTHWEST WINDS. ALL PRECIPITATION WILL EXIT THE COAST BY FRIDAY
EVENING WITH SKIES CLEARING BEHIND IT...BRINGING VFR CONDITIONS TO
THE REGION ONCE AGAIN. VFR CONDITIONS ARE EXPECT THROUGH THE
WEEKEND.
&&
.MARINE...
HIGH PRESSURE HAS PUSHED OFFSHORE THIS AFTERNOON AS A WARM FRONT
LIFTS NWD FROM NC. BENIGN CONDITIONS (WINDS GENERALLY AOB 5-10 KT)
OVER THE WATERS WILL QUICKLY GIVE WAY TO INCREASING SLY WINDS THIS
EVENING THROUGH TONIGHT AS THE WARM FRONT LIFTS OVER OF THE WATERS.
GRADIENT WILL STRENGTHEN OVER THE WATERS IN ADVANCE OF A STRONG COLD
FRONT WITH SLY WINDS REACHING SCA SPEEDS AROUND MIDNIGHT TONIGHT.
WHILE A STRONG LOW LEVEL INVERSION WILL PREVENT THE STRONGEST WINDS
ALOFT FROM REACHING THE WATER...PRESSURE FALLS AND THE TIGHT
GRADIENT WILL PRODUCE WINDS OF 15-25 KT OVER THE BAY AND 20-30 KT
OVER THE COASTAL WATERS. STRONG WINDS WILL CONTINUE INTO FRI BEFORE
THE COLD FRONT CROSSES THE WATERS FRIDAY AFTERNOON. SHOWERS AND
THUNDERSTORMS WILL ALSO ACCOMPANY THE FRONT...WHICH MAY PRODUCE
STRONGER WIND GUSTS WITH CONVECTION. AS THE FRONT CROSSES THE WATERS
AND WINDS BACK TO THE NW...ANTICIPATE A QUICK SURGE POST FRONTAL
BEFORE WINDS DIMINISH FRIDAY NIGHT AS HIGH PRESSURE BUILDS IN FROM
THE SOUTHWEST. WAVES MAY BRIEFLY INCREASE TO 4 FT AROUND MIDDAY
FRIDAY ON THE BAY. MEANWHILE...SEAS WILL BUILD TO 5-6 FT ON THE
SOUTHERN COASTAL WATERS...AND 6-8 FT ON THE NORTHERN COASTAL WATERS.
HEADLINES ARE IN EFFECT FOR ALL WATERS FROM AFTER MIDNIGHT TONIGHT
THROUGH 4PM FRIDAY. RIVERS DROP OFF FIRST BEFORE THE BAY AT 6PM AND
THE NRN COASTAL WATERS AT MIDNIGHT FRI NIGHT. HIGH PRESSURE REMAINS
OVER THE WATERS THROUGH THE WEEKEND BEFORE A CLIPPER FRONT CROSSES
THE WATERS SUNDAY NIGHT-MONDAY MORNING.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 4 PM EST FRIDAY FOR
ANZ635>638.
SMALL CRAFT ADVISORY FROM 1 AM TO 6 PM EST FRIDAY FOR
ANZ630>634.
SMALL CRAFT ADVISORY FROM 1 AM FRIDAY TO MIDNIGHT EST FRIDAY
NIGHT FOR ANZ650-652-654.
SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST FRIDAY FOR ANZ656-
658.
&&
$$
SYNOPSIS...BMD
NEAR TERM...BMD
SHORT TERM...BMD
LONG TERM...SAM
AVIATION...JDM/JAB
MARINE...SAM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1244 PM EST THU FEB 20 2014
.SYNOPSIS...
A STALLED FRONTAL BOUNDARY ACROSS NORTH CAROLINA TODAY...WILL
MOVE BACK NORTH AS A WARM FRONT TONIGHT. A COLD FRONT MOVES
ACROSS THE AREA FRIDAY. HIGH PRESSURE RETURNS FOR THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FRONTAL BOUNDARY THAT DROPPED THROUGH THE FA LAST NIGHT PROGGED
TO STALL ACROSS NC TODAY AS WEAK HIGH PRESSURE DRIFTS EAST THEN
OFF THE NORTHERN MID ATLANTIC COAST THIS AFTERNOON. TSCTNS SHOW
PLENTY OF MOISTURE AT VARIOUS LEVELS DUE THE MID LEVEL MOISTURE
SEEN CAUGHT UP IN THE UPR LEVEL FLOW COMBINED WITH THE LOW LEVEL
MOISTURE DUE TO THE LIGHT E-SE FLOW AROUND THE DEPARTING HIGH.
UPSHOT WILL BE SKIES BECMG M CLDY TO CLDY (CIGS BTWN 2-5K FT) AS
THE DAY PROGRESSES.
SREF/NAM JUST SHOWING JUST CLOUDS BUT GFS TRIES TO DVLP SOME LGT
SHWRS/SPRINKLES ACROSS THE PIEDMONT (WEST OF I95) AFTER 18Z AS THE
FRONTAL BOUNDARY BEGINS TO RETURN NORTH AS A WARM FRONT. ALTHOUGH
A SPRINKLE NOT OUT OF THE QUESTION W OF I95...CHCS ARE RATHER LOW
SO KEPT A DRY FCST TODAY BUT INDICATED A 14 POP W OF I95. COOLER
DUE TO CLOUDS AND ONSHORE FLOW. HIGHS 55-60 NORTH...60-65 SOUTH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
A MORE AMPLIFIED TROUGH APPROACHES THE REGION TONIGHT. THE PRIMARY
MID-LEVEL LOW LIFTS NNE ACROSS THE GREAT LAKES WHICH ALLOWS THE
WARM FRONT TO LIFT NORTH ACROSS THE AREA...WITH THE MODELS NOW
SHOWING THE TRAILING COLD FRONT IVOF THE I81 CORRIDOR BY 12Z FRI.
A SUSTAINED SOUTH WIND KEEPS MINS FROM DROPPING MUCH...WITH READINGS
RISING OVERNIGHT AS SRLY FLOW INCREASES DUE TO THE TIGHTENING PRS
GRADIENT. LOWS FROM U40S/ARND 50 F NORTH TO THE M-U50S SOUTH AROUND
MIDNIGHT RISING INTO THE M50S-L60S BY 12Z FRI. SCT SHWRS PROGGED
TO DVLP ACROSS THE WRN PIEDMONT AFTER 09Z.
ALL MODELS HAVE THE COLD FRONT CROSSING THE FA FRI. SPC HAS CWA IN
SLIGHT RISK FOR SEVERE (PRIMARILY WINDS). A FEW MAIN THINGS EXIST
THAT WOULD SUGGEST ONLY A MINIMAL CHANCE FOR SEVERE WX: 1) TIMING IS
EARLY IN THE PERIOD...WITH LITTLE CHANCE FOR DAYTIME HEATING EXCEPT
OVER THE FAR SE ZONES. 2) THE MID LVL TROUGH / SHORTWAVE BECOMES
NEGATIVELY TILTED WELL OFF TO OUR NW TONIGHT/FRI...SUGGESTING THAT
THE BEST ENERGY FOR STRONG STORMS WOULD REMAIN WEST OF THE MTNS
WHERE THE FRONTOGENETIC FIELDS WEAKEN...AND THE BOUNDARY TAKES ON
MORE OF AN ANAFRONTAL STRUCTURE. CATEGORICAL POPS (90%) ALL AREAS...
MAINLY IN THE LATE MORNING TO EARLY AFTN TIMEFRAME. KEPT A PERIOD
OF SLIGHT CHC TSTMS IN THE NW...AND CHC TSTMS SE...BUT THINK THAT
STORMS WILL GENLY BE SUB-SEVERE IN NATURE (WITH BEST CHC FOR SEVERE
BEING OVER FAR SE VA/NE NC). WILL MENTION THIS IN HWO. HIGH TMPS
WILL DEPEND ON ACTUAL TIMING OF FROPA & PCPN. EXPECT MORNING HIGHS
IN THE 60S... NR 70 SERN AREAS WITH STEADLY OR FALLING READINGS IN
THE AFTERNOON. TSCTNS SHOW COLUMN DRYING ACROSS WESTERN HALF OF FA
AFTER 18Z LEADING TO SOME PARTIAL SUNSHINE. TOTAL QPF ONE THIRD TO
ONE HALF INCH.
LINGERING SHOWERS ACROSS THE SERN COASTAL AREAS QUICKLY END ERLY FRI
EVENING. OTW...DRY WX FRI NIGHT/SAT AND STAYING FAIRLY MILD AS LOW
LEVEL FLOW IS WSW SO COLDER AIR REMAINS OVER THE MIDWEST/NE STATES.
LOWS FRI NIGHT IN THE 30S...PT TO MSTLY SSAT. HIGHS 60-65.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
MEDIUM RANGE GUIDANCE GENERALLY IN GOOD AGREEMENT WITH UPPER AIR
PATTERN THROUGH THE EXTENDED PERIOD AS THE NRN STREAM REMAINS
ACTIVE. SFC HIGH PRESSURE WILL SLIDE OFFSHORE SAT NIGHT-SUN MORNING
AS A CLIPPER FRONT APPROACHES FROM THE WEST. ECMWF IS MORE
AMPLIFIED/STRONGER WITH THE SHORTWAVE ENERGY OVER THE GREAT LAKES
REGION SUN...WHILE ITS GFS COUNTERPART REMAINS MAINLY ZONAL OVER THE
MID-ATLANTIC. AS A RESULT...THE GFS PUSHES THE FRONT THROUGH THE
REGION QUICKER THAN THE ECMWF. THIS WILL MOSTLY IMPACT HIGH TEMPS
SUN AS THE FRONT REMAINS DRY (BOTH GLOBAL MODELS KEEP PRECIP
CONFINED WELL SOUTH OF THE LOCAL AREA). HAVE TRENDED TOWARD THE
WARMER ECMWF WITH HIGHS IN THE LOW-MID 60S UNDER PARTLY CLOUDY SKIES
(COOLER ALONG THE COAST AND ERN SHORE). THEREAFTER...BROAD CYCLONIC
FLOW WILL REMAIN OVER THE ERN CONUS THROUGH THE EXTENDED PERIOD AS
ADDITIONAL SHORTWAVE ENERGY DIGS OVER THE OH VALLEY.
HOWEVER...SPATIAL AND TIMING DIFFERENCES WRT TO SHORTWAVE ENERGY
WILL IMPACT HOW DEEP THE TROUGH BECOMES AND HOW FAR SOUTH THE
ASSOCIATED COLD AIR REACHES. HAVE TRENDED TEMPS BELOW SEASONABLE
NORMS BEGINNING MONDAY. BEST CHANCE FOR PRECIP DURING THE EXTENDED
LOOKS TO BE TUES-WEDS AS A SFC LOW DEVELOPS ALONG A COLD FRONT OVER
THE GULF STATES/NRN GULF TUES NIGHT. SFC LOW WILL LIFT ALONG THE SE
COAST AND OFF THE MID-ATLANTIC COAST WEDS MORNING...PULLING AWAY
FROM THE REGION WEDS AFTERNOON. WILL MAINTAIN SLIGHT CHANCE POPS DUE
TO MODEL UNCERTAINTY AND LIMITED MOISTURE AND TREND TEMPS COOLER.
COULD ALSO SEE FROZEN PRECIP TUES NIGHT-WEDS MORNING...MAINLY OVER
THE NRN LOCAL AREA.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
FRONTAL BOUNDARY WILL SLOWLY NORTH NORTH THROUGH THE AREA TONIGHT.
THE FRONT ALOFT IS GENERATING SOME CLOUDS THIS AFTERNOON AND
EVENING ALL WILL BE VFR CIGS. NO PRECIPITATION IS EXPECTED. LATER
TONIGHT ALL MODELS SHOW MOISTURE ADVECTING NORTH OFF THE GULF
STREAM AND ACROSS THE AREA AT THE LOW LEVELS. MODELS ALL DEVELOP
IFR STRATUS CLOUDS AFTER 06Z TONIGHT. STILL NOT COMPLETELY
CONVINCED ON THIS AS THE SREF ONLY DEPICTS IT FOR KRIC AND KSBY.
HOWEVER ALL BUFKIT SOUNDINGS FROM THE GFS NAM AND RAP SHOW IT AT
ALL THE SITES. SO DEVELOPED IFR CIGS AFTER 06Z TONIGHT. MODELS ARE
SLOW TO BREAK THESE CLOUDS IN THE MORNING ON FRIDAY SO ONLY SLOWLY
RAISE CIGS TO MVFR DURING THE MORNING. COLD FRONT WILL BE
APPROACHING KRIC BY THE END OF THE PERIOD AND BRING SHOWERS INTO
RIC AFTER 15Z AND KPHF BY 17Z. THERE COULD BE ISOLATED
THUNDERSTORMS ACCOMPANYING THE FRONT AS IT MOVES THROUGH. EXPECT
CIGS AND POTENTIALLY VSBY TO BECOME IFR WITH THESE SHOWERS. ALL
PRECIPITATION WILL EXIT THE COAST BY FRIDAY EVENING WITH SKIES
CLEARING BEHIND IT GIVING VFR CONDITIONS AGAIN.
VFR CONDITIONS ARE EXPECT THROUGH THE WEEKEND.
&&
.MARINE...
HIGH PRESSURE CENTERED OVER THE WATERS THIS MORNING WILL MOVE
EASTWARD BY LATER TODAY AS A WARM FRONT LIFTS NWD OVER THE REGION.
LIGHT NE WINDS WILL GRADUALLY VEER AROUND TO THE SOUTHEAST BY LATE
TODAY. WINDS BECOME SOUTHERLY AND INCREASE TONIGHT IN ADVANCE OF A
COLD FRONT THAT WILL CROSS THE WATERS FRIDAY AFTERNOON. SHOWERS AND
THUNDERSTORMS WILL ACCOMPANY THE FRONTAL PASSAGE. SCA`S HAVE BEEN
HOISTED FOR FRIDAY AS SLY WINDS OF 15-20 KT WITH GUSTS TO 25 KT ON
THE BAY/ERN VA RIVERS/CURRITUCK SOUND AND 20-25 KT WITH GUSTS TO 30
KT FOR THE COASTAL WATERS APPEAR LIKELY. WAVES MAY BRIEFLY INCREASE
TO 4 FT AROUND MIDDAY FRIDAY ON THE BAY. MEANWHILE...SEAS WILL BUILD
TO 5-6 FT ON THE SOUTHERN COASTAL WATERS...AND 6-8 FT ON THE NORTHERN
COASTAL WATERS. WINDS/WAVES/SEAS WILL DIMINISH/SUBSIDE LATE FRIDAY
IN THE WAKE OF THE FRONT. HIGH PRESSURE RETURNS THROUGH THE WEEKEND.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 3 AM TO 1 PM EST FRIDAY FOR
ANZ635>638.
SMALL CRAFT ADVISORY FROM 3 AM TO 4 PM EST FRIDAY FOR
ANZ630>634.
SMALL CRAFT ADVISORY FROM 3 AM FRIDAY TO MIDNIGHT EST FRIDAY
NIGHT FOR ANZ650-652-654.
SMALL CRAFT ADVISORY FROM 3 AM TO 7 PM EST FRIDAY FOR ANZ656-
658.
&&
$$
SYNOPSIS...MPR
NEAR TERM...MPR
SHORT TERM...LKB/MPR
LONG TERM...SAM
AVIATION...JDM/JAB
MARINE...JDM
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1142 AM CST Thu Feb 20 2014
.UPDATE:
Issued at 1032 AM CST Thu Feb 20 2014
Surface low in the MKC vicinity will deepen and move northeastward
this afternoon and evening in response the strong upstream
shortwave trof progressing into and across the region. The
attendant cold front is still forecast to begin accelerating and
sweep across the CWA this afternoon, exiting our south central IL
counties near 00Z. Winds will be increasing both ahead and
especially behind the cold front, with mixing and a tight pressure
gradient associated with the deepening low contributing to strong
post-frontal sw/w winds gusting from 45-50 mph. The current wind
advisory looks right on target, although the timing of the cold
front passage in IL has resulted in moving up the onset of the
wind advisory to 21Z to the east of the MS river. Still monitoring
the severe weather potential for this afternoon. The amount of
instability is the biggest unknown. The RAP and NAM both have
SBCAPE increasing to above 1000 j/kg by mid-afternoon in a
north/south corridor across eastern MO just ahead of the cold
front but based on the latest SPC mesoanalysis, this may be a
little high. If we can get tds into the u50s and some decent
heating this may materialize, otherwise 500-1000 j/kg seems more
probable. The very strong wind fields will support a threat of
damaging winds with any strong storms, with higher CAPE values
supporting greater storm coverage and damaging wind potential as
well as isolated tornadoes. Present indications are that scattered
storms should develop along the front this afternoon in response
to linear forcing associated with the front and upper wave, likely
between Columbia and St. Louis, but possibly as far west as COU.
Eventually upscale growth will result in a strongly forced line of
storms, most likely evolving near or just east of St. Louis.
Glass
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 405 AM CST Thu Feb 20 2014
It`s going to be one of those days.
Lots of wx expected so here goes. At 09z, surface obs show a warm
front poking into central MO near COU/JEF and then sagging somewhat
down to near FAM. Temps rise quickly into the 50s with warm FROPA
with dewpoints in the 50s following not long thereafter. Temps are
only in the 30s for the far northern CWA, including UIN. Radar
shows a cluster of TSRA in southwest MO moving northeast. Much of
the rest of the area just has scattered SHRA or nothing at all with
much of the pcpn from earlier having shifted further north.
Pcpn chances: local 4km WRF model has an excellent handle on things
and used this for primary guidance today. It tracks the cluster of
TSRA northeast thru most of central...east-central MO and southwest
IL this morning. Then a lull in the action for much of our region
from just before midday thru about mid-afternoon. All models are on
board with a slower frontal timing and by all accounts should see
sfc-based TSRA develop along cold front between 20-21z from
UIN-STL-UNO and then expand and continue to track eastward along
front for remainder of the afternoon...exiting around 00z. Could
see severe chances being revisited despite current SPC day 1 outlook
if this scenario verifies.
Flood potential: combo of very moist soil/frozen soil and QPF and
still existant snowpack is best in northeast MO and west-central IL
and current flood watch is justified. More in doubt in central MO,
though, where snow melted a couple days ago, soil is not frozen but
is moist, but QPF also more limited with what moves thru with the
cluster of TSRA to the south probably it for the day. Will trim
flood watch to remove pertinent sections of central MO.
Winds: strong lo level jet of 50kts already exists but passage of
warm front will not allow too much mixing, either, with gusts
expected to reach to 30-35mph. The really strong gusts will hold
off until passage of cold front later this afternoon, allowing for
deeper mixing and tapping the high winds aloft. Looks like gusts
45-50mph will be common across much of the area at some point into
the evening, perhaps longer, and will issue a Wind Advisory.
Temps: a challenge to say the least. Clouds and pcpn will try to
keep the warmup in check, but dry slot also expected to push into
STL metro and areas S and E later today and allow for decent rise to
near 70F. Look for temp fall for central-northeast MO this
afternoon behind front.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 405 AM CST Thu Feb 20 2014
Showers and thunderstorms along a fast moving cold front should
shift rapidly east of our forecast area by late evening. Some
light rain/snow in the southwestern tail of the deformation zone,
wrap around precipitation may graze our nern MO and w central IL
counties early this evening. Strong and gusty winds will continue
this evening due to the tight surface pressure gradient behind the
deepening surface low moving northeastward through WI this
evening. The winds should begin to gradually slacken by late
tonight. Much colder temperatures tonight due to low level cold
air advection behind the cold front this evening, a clearing sky,
and lowering surface dew points tonight. This cooling trend will
be short lived as 850 mb temperatures slowly warm from sw to ne on
Friday. Although Fridays highs will not be as warm as Thursday
they will still be above normal. A weak cold front will sag slowly
southward through our forecast area late Friday night and
Saturday. There could be patchy light rain or snow along this
front. Should be the start of a gradual cooling trend Saturday
night and Sunday as a large and relatively strong surface ridge
builds southeastward into our area from the northern Plains. The
ECMWF model was depicting some light qpf Monday and Monday night
across our forecast area, which should be mainly in the form of
snow, due to low-mid level warm air advection ahead of a
southeastward moving shortwave moving through the northern Plains.
The GFS model keeps most of the precipitation north of our
forecast area. Even colder, well below normal temperatures
expected for Tuesday night as another surface ridge builds
southeastward into our area.
GKS
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1127 AM CST Thu Feb 20 2014
Surface low now NW of KMKC will move northeastward this afternoon
and tonight with the warm front lifting northward through KUIN
within the next hour or so, and the trailing cold front sweeping
eastward across the area this afternoon. Predominately VFR
conditons are expected ahead of the cold front along with gusty
southerly winds. The exception is with any thunderstorms occurring
along/ahead of front which could drop flight conditions briefly
to IFR and contain strong winds. Coverage of any storms is hard to
judge at this time and thus have just mentioned Vicinity in the
current TAFS and will update as needed once coverage and impacts
can be determined. Very strong southwest-west winds gusting 38-45
kts will occur with the passage of the cold front, along with a
period of MVFR cigs. Clouds will clear this evening and the winds
should diminish some this evening but will remain gusty through
the period.
Specifics for KSTL:
VFR conditions and gusty southerly winds are expected until a cold front
passage around 22z. Thunderstorm chances/coverage with the cold
front are hard to judge at this time, and thus have kept with a
mention of VCTS and will update if needed once coverage and impacts
can be determined. Very strong southwest-west winds gusting 38-45
kts will occur with the passage of the cold front at 22z, along
with a period of MVFR cigs into mid-evening. Clouds will clear
around 02-03z and the winds should diminish some this evening but
will remain gusty through the period.
Glass
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WIND ADVISORY until Midnight CST tonight FOR Audrain MO-Boone MO-
Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-
Iron MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Madison MO-
Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike
MO-Ralls MO-Reynolds MO-Shelby MO-St. Charles MO-St.
Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve
MO-Warren MO-Washington MO.
FLOOD WATCH until 6 PM CST this evening FOR Knox MO-Lewis MO-
Marion MO-Shelby MO.
IL...WIND ADVISORY until Midnight CST tonight FOR Adams IL-Brown IL-
Calhoun IL-Greene IL-Jersey IL-Macoupin IL-Madison IL-
Monroe IL-Pike IL-St. Clair IL.
WIND ADVISORY from 3 PM this afternoon to Midnight CST tonight
FOR Bond IL-Clinton IL-Fayette IL-Marion IL-Montgomery IL-
Randolph IL-Washington IL.
FLOOD WATCH until 6 PM CST this evening FOR Adams IL-Brown IL-
Greene IL-Macoupin IL-Montgomery IL-Pike IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1140 AM CST Thu Feb 20 2014
.UPDATE...
Issued at 1001 AM CST THU FEB 20 2014
Latest model data and trends from radar indicate that north central
to northeast Missouri will likely be spared from widespread rains
that could induce flooding. Therefore have dropped the Flood Watch
for that was still in effect for that section of the forecast area.
Shower and thunderstorm activity will remain focused more across
northeast Kansas and northwest Missouri this morning where a
combination of rain, changing to sleet and snow, will occur through
the early afternoon hours. Snowfall totals in far northwest Missouri
remain very difficult to forecast owing to the fact that surface
temperatures are currently, and are expected to remain, above
freezing through much of the daylight hours while its precipitating.
But, the dynamics of the deformation band aloft still look sufficient
to put down a couple quick inches of slushy accumulations from
Maryville south through St Joseph and possibly into the far northern
side of Kansas City...and as far east as Interstate 35.
&&
.SHORT TERM...(Today and Tonight)
Issued at 430 AM CST THU FEB 20 2014
At the surface a very strong trough has formed on the eastern side
of the Rocky mountains, and currently sits over SC/SE Kansas. The
surface pressure gradient associated with this very strong trough
will cause southerly winds to pick up on the eastern edge to around
20 to 30 mph with gusts approaching 40 mph later today. An evident
surface warm front currently sits along Interstate 70, and is
characterized by temperatures in the 30s to lower 40s north of the
boundary to temperatures well in the 50s to lower 60s in the warm
sector south of the boundary. Thunderstorms are currently forming
along along the advancing warm front and will have plenty of
instability to grow upscale into strong thunderstorms. This activity
is generally forming along a strong low level jet which is currently
nosing into western Missouri, and is characterized by strong 850
winds between 50 and 60 kts. Effective bulk shear is between 40 and
50 kts, and given strong MU elevated CAPE of around 1000 J/kg the
ingredients are in place for these storms to be strong to marginally
severe. As the morning progresses HRRR indicates that these storms
will form a line spanning west to east just north of Interstate 70,
and will lift north through the day. Expect the bulk of the strong
thunderstorm potential to move northward into Iowa by around 10 am.
The focus then shifts to the late morning and afternoon hours, when
areas of far northwestern Missouri could experience a period of
moderate to heavy snow. The main mid level trough, which currently
sits over the High Plains will swing through the area later this
afternoon. Southern and Central Missouri will likely see a down tick
in precipitation coverage as the systems dry slot races through
southern and central Missouri. Across northern Missouri large scale
ascent associated with the mid level trough will bring another round
of precipitation later this morning. The aforementioned surface
trough will continue eastward, and behind the departing trough cold
northwest winds will crash into the area causing the thermal profile
to cool very quickly. By mid morning the thermal profile along
northern Missouri will be cooled adequately for snow production.
Very strong low/mid level frontogenesis in northern Missouri, as
well as some negative EPV will enhance the lift associated with the
mid level wave. All told there could be up to 15 to 20 -ubar of
Omega this morning and this afternoon contributing to rather
efficient snow production. While cold air will rush in surface
temperatures will struggle to drop below freezing, so any snow
production and accumulation may be mitigated by the warmer surface
temperatures. Went with a general 10-12:1 snow ratio to attain a
final figure of around 2 to 4 inches of snow accumulation for the
far NW corner of Missouri, with decreasing amounts toward the east
and south. Concurrent to the snow will be strong northwest winds,
which will race in as the surface pressure gradient behind the
departing trough moves through the area this afternoon. Expect the
winds to be sustained out of the northwest around 30 to 40 mph, with
gusts perhaps exceeding 50 mph. The strong winds and period of
moderate to heavy snow will cause visibility to decrease through the
day. Expect the period of snowfall to be rather brief as the overall
system quickly glides off to the northeast. By mid afternoon expect
the bulk of the precipitation to be off to the north, with perhaps
some lingering rain/snow through the evening.
Model soundings indicate that the low levels could stay well mixed
through the evening and into the overnight hours, which would allow
the strong wind gusts to continue at least into the evening and
perhaps into the overnight hours before gradually dissipating early
Friday morning.
.LONG TERM...(Friday through Wednesday)
Issued at 430 AM CST THU FEB 20 2014
A return to a West Coast blocking pattern, similar to what prevailed
through much of January, will send us back into a cold and dry
pattern by early next week. Primary cold front will drop into the
forecast area Friday night with a reinforcing shot of cold air
arriving Sunday. Temperatures in this pattern won`t be near as cold
as they were back in January, but still about 10 degrees below
average with highs in the 20s and 30s and lows in the teens and 20s
for much of next week. Could see some light snow Monday and Monday
night with a broad upper impulse tracking through the Upper Midwest
but better chances will be to our north.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon)
Issued at 1139 AM CST THU FEB 20 2014
Most of the thunderstorm activity cleared the terminals by the late
morning hours, and while a few more showers and isolated
thunderstorms may be possible any of that activity will likely occur
to the east of our locations. Now waiting for a band of rain, sleet
and snow to move across western Missouri this afternoon. Conditions
should be a bit worse the farther north you go, but with above
freezing surface temperatures prevailing precipitation type will be
hard to pin down. Otherwise, strong and gusty northwest winds will
persist through the rest of the daylight hours diminishing this
evening as they back to the west. The decrease in wind speed should
accompany VFR conditions.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY until 9 PM CST this evening FOR KSZ025-057-060-
102>105.
WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR KSZ025-
102.
MO...WIND ADVISORY until 9 PM CST this evening FOR MOZ001>005-011>014-
020>022-028>031-037>040-043>046-053-054.
WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR
MOZ001>005-011>013-020.
WIND ADVISORY until Midnight CST tonight FOR MOZ006>008-015>017-
023>025-032-033.
&&
$$
UPDATE...Cutter
SHORT TERM...Leighton
LONG TERM...Hawblitzel
AVIATION...Cutter
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1040 AM CST Thu Feb 20 2014
.UPDATE:
Issued at 1032 AM CST Thu Feb 20 2014
Surface low in the MKC vicinity will deepen and move northeastward
this afternoon and evening in response the strong upstream
shortwave trof progressing into and across the region. The
attendant cold front is still forecast to begin accelerating and
sweep across the CWA this afternoon, exiting our south central IL
counties near 00Z. Winds will be increasing both ahead and
especially behind the cold front, with mixing and a tight pressure
gradient associated with the deepening low contributing to strong
post-frontal sw/w winds gusting from 45-50 mph. The current wind
advisory looks right on target, although the timing of the cold
front passage in IL has resulted in moving up the onset of the
wind advisory to 21Z to the east of the MS river. Still monitoring
the severe weather potential for this afternoon. The amount of
instability is the biggest unknown. The RAP and NAM both have
SBCAPE increasing to above 1000 j/kg by mid-afternoon in a
north/south corridor across eastern MO just ahead of the cold
front but based on the latest SPC mesoanalysis, this may be a
little high. If we can get tds into the u50s and some decent
heating this may materialize, otherwise 500-1000 j/kg seems more
probable. The very strong wind fields will support a threat of
damaging winds with any strong storms, with higher CAPE values
supporting greater storm coverage and damaging wind potential as
well as isolated tornadoes. Present indications are that scattered
storms should develop along the front this afternoon in response
to linear forcing associated with the front and upper wave, likely
between Columbia and St. Louis, but possibly as far west as COU.
Eventually upscale growth will result in a strongly forced line of
storms, most likely evolving near or just east of St. Louis.
Glass
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 405 AM CST Thu Feb 20 2014
It`s going to be one of those days.
Lots of wx expected so here goes. At 09z, surface obs show a warm
front poking into central MO near COU/JEF and then sagging somewhat
down to near FAM. Temps rise quickly into the 50s with warm FROPA
with dewpoints in the 50s following not long thereafter. Temps are
only in the 30s for the far northern CWA, including UIN. Radar
shows a cluster of TSRA in southwest MO moving northeast. Much of
the rest of the area just has scattered SHRA or nothing at all with
much of the pcpn from earlier having shifted further north.
Pcpn chances: local 4km WRF model has an excellent handle on things
and used this for primary guidance today. It tracks the cluster of
TSRA northeast thru most of central...east-central MO and southwest
IL this morning. Then a lull in the action for much of our region
from just before midday thru about mid-afternoon. All models are on
board with a slower frontal timing and by all accounts should see
sfc-based TSRA develop along cold front between 20-21z from
UIN-STL-UNO and then expand and continue to track eastward along
front for remainder of the afternoon...exiting around 00z. Could
see severe chances being revisited despite current SPC day 1 outlook
if this scenario verifies.
Flood potential: combo of very moist soil/frozen soil and QPF and
still existant snowpack is best in northeast MO and west-central IL
and current flood watch is justified. More in doubt in central MO,
though, where snow melted a couple days ago, soil is not frozen but
is moist, but QPF also more limited with what moves thru with the
cluster of TSRA to the south probably it for the day. Will trim
flood watch to remove pertinent sections of central MO.
Winds: strong lo level jet of 50kts already exists but passage of
warm front will not allow too much mixing, either, with gusts
expected to reach to 30-35mph. The really strong gusts will hold
off until passage of cold front later this afternoon, allowing for
deeper mixing and tapping the high winds aloft. Looks like gusts
45-50mph will be common across much of the area at some point into
the evening, perhaps longer, and will issue a Wind Advisory.
Temps: a challenge to say the least. Clouds and pcpn will try to
keep the warmup in check, but dry slot also expected to push into
STL metro and areas S and E later today and allow for decent rise to
near 70F. Look for temp fall for central-northeast MO this
afternoon behind front.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 405 AM CST Thu Feb 20 2014
Showers and thunderstorms along a fast moving cold front should
shift rapidly east of our forecast area by late evening. Some
light rain/snow in the southwestern tail of the deformation zone,
wrap around precipitation may graze our nern MO and w central IL
counties early this evening. Strong and gusty winds will continue
this evening due to the tight surface pressure gradient behind the
deepening surface low moving northeastward through WI this
evening. The winds should begin to gradually slacken by late
tonight. Much colder temperatures tonight due to low level cold
air advection behind the cold front this evening, a clearing sky,
and lowering surface dew points tonight. This cooling trend will
be short lived as 850 mb temperatures slowly warm from sw to ne on
Friday. Although Fridays highs will not be as warm as Thursday
they will still be above normal. A weak cold front will sag slowly
southward through our forecast area late Friday night and
Saturday. There could be patchy light rain or snow along this
front. Should be the start of a gradual cooling trend Saturday
night and Sunday as a large and relatively strong surface ridge
builds southeastward into our area from the northern Plains. The
ECMWF model was depicting some light qpf Monday and Monday night
across our forecast area, which should be mainly in the form of
snow, due to low-mid level warm air advection ahead of a
southeastward moving shortwave moving through the northern Plains.
The GFS model keeps most of the precipitation north of our
forecast area. Even colder, well below normal temperatures
expected for Tuesday night as another surface ridge builds
southeastward into our area.
GKS
&&
.AVIATION: (For the 12z TAFs through 12z Friday Morning)
Issued at 615 AM CST Thu Feb 20 2014
Warm front now pushing thru I-70 corridor TAF sites and should
further enhance probs of reaching IFR CIGs for areas to the north
this morning: namely UIN. Further to the south, CIGs will bounce
around until warm front gets further north thru these areas with
advance of dry slot later in the day to have CIGs either go
solidly VFR or breakup. Pcpn expected to largely exit the area by
late morning as well. Cold front will shift winds to SW-W,
increase them substantially, and ignite a new round of TSRA for
STL metro for a short period this afternoon before it heads east.
Strong W winds will then persist into this evening before slow
diminishment.
Specifics for KSTL: TSRA thru mid-morning with CIGs bouncing
around before a more steady period of VFR and dry for late
morning and early afternoon. Cold front late this afternoon will
attempt to ignite a new round of TSRA and strengthen the winds as
they shift out of the west. The strong W winds will then continue
into the evening before a slow diminishment.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...WIND ADVISORY until Midnight CST tonight FOR Audrain MO-Boone MO-
Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-
Iron MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Madison MO-
Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike
MO-Ralls MO-Reynolds MO-Shelby MO-St. Charles MO-St.
Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve
MO-Warren MO-Washington MO.
FLOOD WATCH until 6 PM CST this evening FOR Knox MO-Lewis MO-
Marion MO-Shelby MO.
IL...WIND ADVISORY until Midnight CST tonight FOR Adams IL-Brown IL-
Calhoun IL-Greene IL-Jersey IL-Macoupin IL-Madison IL-
Monroe IL-Pike IL-St. Clair IL.
WIND ADVISORY from 3 PM this afternoon to Midnight CST tonight
FOR Bond IL-Clinton IL-Fayette IL-Marion IL-Montgomery IL-
Randolph IL-Washington IL.
FLOOD WATCH until 6 PM CST this evening FOR Adams IL-Brown IL-
Greene IL-Macoupin IL-Montgomery IL-Pike IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1007 AM CST Thu Feb 20 2014
.UPDATE...
Issued at 1001 AM CST THU FEB 20 2014
Latest model data and trends from radar indicate that north central
to northeast Missouri will likely be spared from widespread rains
that could induce flooding. Therefore have dropped the Flood Watch
for that was still in effect for that section of the forecast area.
Shower and thunderstorm activity will remain focused more across
northeast Kansas and northwest Missouri this morning where a
combination of rain, changing to sleet and snow, will occur through
the early afternoon hours. Snowfall totals in far northwest Missouri
remain very difficult to forecast owing to the fact that surface
temperatures are currently, and are expected to remain, above
freezing through much of the daylight hours while its precipitating.
But, the dynamics of the deformation band aloft still look sufficient
to put down a couple quick inches of slushy accumulations from
Maryville south through St Joseph and possibly into the far northern
side of Kansas City...and as far east as Interstate 35.
&&
.SHORT TERM...(Today and Tonight)
Issued at 430 AM CST THU FEB 20 2014
At the surface a very strong trough has formed on the eastern side
of the Rocky mountains, and currently sits over SC/SE Kansas. The
surface pressure gradient associated with this very strong trough
will cause southerly winds to pick up on the eastern edge to around
20 to 30 mph with gusts approaching 40 mph later today. An evident
surface warm front currently sits along Interstate 70, and is
characterized by temperatures in the 30s to lower 40s north of the
boundary to temperatures well in the 50s to lower 60s in the warm
sector south of the boundary. Thunderstorms are currently forming
along along the advancing warm front and will have plenty of
instability to grow upscale into strong thunderstorms. This activity
is generally forming along a strong low level jet which is currently
nosing into western Missouri, and is characterized by strong 850
winds between 50 and 60 kts. Effective bulk shear is between 40 and
50 kts, and given strong MU elevated CAPE of around 1000 J/kg the
ingredients are in place for these storms to be strong to marginally
severe. As the morning progresses HRRR indicates that these storms
will form a line spanning west to east just north of Interstate 70,
and will lift north through the day. Expect the bulk of the strong
thunderstorm potential to move northward into Iowa by around 10 am.
The focus then shifts to the late morning and afternoon hours, when
areas of far northwestern Missouri could experience a period of
moderate to heavy snow. The main mid level trough, which currently
sits over the High Plains will swing through the area later this
afternoon. Southern and Central Missouri will likely see a down tick
in precipitation coverage as the systems dry slot races through
southern and central Missouri. Across northern Missouri large scale
ascent associated with the mid level trough will bring another round
of precipitation later this morning. The aforementioned surface
trough will continue eastward, and behind the departing trough cold
northwest winds will crash into the area causing the thermal profile
to cool very quickly. By mid morning the thermal profile along
northern Missouri will be cooled adequately for snow production.
Very strong low/mid level frontogenesis in northern Missouri, as
well as some negative EPV will enhance the lift associated with the
mid level wave. All told there could be up to 15 to 20 -ubar of
Omega this morning and this afternoon contributing to rather
efficient snow production. While cold air will rush in surface
temperatures will struggle to drop below freezing, so any snow
production and accumulation may be mitigated by the warmer surface
temperatures. Went with a general 10-12:1 snow ratio to attain a
final figure of around 2 to 4 inches of snow accumulation for the
far NW corner of Missouri, with decreasing amounts toward the east
and south. Concurrent to the snow will be strong northwest winds,
which will race in as the surface pressure gradient behind the
departing trough moves through the area this afternoon. Expect the
winds to be sustained out of the northwest around 30 to 40 mph, with
gusts perhaps exceeding 50 mph. The strong winds and period of
moderate to heavy snow will cause visibility to decrease through the
day. Expect the period of snowfall to be rather brief as the overall
system quickly glides off to the northeast. By mid afternoon expect
the bulk of the precipitation to be off to the north, with perhaps
some lingering rain/snow through the evening.
Model soundings indicate that the low levels could stay well mixed
through the evening and into the overnight hours, which would allow
the strong wind gusts to continue at least into the evening and
perhaps into the overnight hours before gradually dissipating early
Friday morning.
.LONG TERM...(Friday through Wednesday)
Issued at 430 AM CST THU FEB 20 2014
A return to a West Coast blocking pattern, similar to what prevailed
through much of January, will send us back into a cold and dry
pattern by early next week. Primary cold front will drop into the
forecast area Friday night with a reinforcing shot of cold air
arriving Sunday. Temperatures in this pattern won`t be near as cold
as they were back in January, but still about 10 degrees below
average with highs in the 20s and 30s and lows in the teens and 20s
for much of next week. Could see some light snow Monday and Monday
night with a broad upper impulse tracking through the Upper Midwest
but better chances will be to our north.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday Morning)
Issued at 516 AM CST THU FEB 20 2014
Cluster of thunderstorms currently affecting KMCI and KSTJ will move
off to the north within the next couple hours. Not expecting much in
the way of convective redevelopment once these showers pass, however
there will be the chance for some light rain/snow mix later this
afternoon. The bigger story for this afternoon will be the very
strong winds, which will race into the area bringing 30 to 40 kt
gusts later this afternoon. Expect winds to gradually dissipate later
this evening, but winds will still be out of the northwest around 15
to 25 kts.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...WIND ADVISORY until 9 PM CST this evening FOR KSZ025-057-060-
102>105.
WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR KSZ025-
102.
MO...WIND ADVISORY until 9 PM CST this evening FOR MOZ001>005-011>014-
020>022-028>031-037>040-043>046-053-054.
WINTER WEATHER ADVISORY until 3 PM CST this afternoon FOR
MOZ001>005-011>013-020.
WIND ADVISORY from 1 PM this afternoon to Midnight CST tonight
FOR MOZ006>008-015>017-023>025-032-033.
&&
$$
UPDATE...Cutter
SHORT TERM...Leighton
LONG TERM...Hawblitzel
AVIATION...Leighton
AREA FORECAST DISCUSSION
NWS RALEIGH NC
244 PM EST THU FEB 20 2014
.SYNOPSIS...A WARM FRONT WILL MOVE NORTH OF THE AREA THIS
EVENING...WITH A STRONG COLD FRONT TO SWEEP EAST ACROSS THE AREA
FRIDAY. HIGH PRESSURE WILL BUILD INTO THE REGION FOR THE FIRST PART
OF THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
AS OF 1045 AM THURSDAY...
REST OF TODAY: ONLY SMALL CHANGES NEEDED TO THE EXISTING FORECAST.
THE DEW POINT DISCONTINUITY IS VERY APPARENT WITH VALUES RANGING
FROM THE MID 30S IN THE FAR NORTH (WHERE SURFACE WINDS ARE MORE
EASTERLY OR ENE) TO LOWER 50S IN THE SOUTH (WITH MORE SOUTHEASTERLY
SURFACE WINDS). THIS WARM FRONTAL ZONE IS EXPECTED TO TRANSLATE
NORTHWARD TODAY... ALBEIT WITH LITTLE FANFARE AS INCOMING PRECIP
WATER (ACCORDING TO BLENDED TPW IMAGERY) REMAINS BELOW ONE INCH WITH
CONSIDERABLE DRY AIR THROUGH THE COLUMN (ACCORDING TO UPSTREAM
SOUNDINGS AND RAP FORECAST SOUNDINGS) AND AN ABSENCE OF FORCING FOR
ASCENT. CONVECTION-ALLOWING MODELS PICK UP ON THE PATCHY SPRINKLES
IN THE FAR NW CWA BUT THESE ARE EXPECTED TO DRY UP AND HEAD TO OUR
NORTH IN THE NEXT COUPLE OF HOURS... RESULTING IN A POP-FREE
AFTERNOON AREAWIDE. THE LATEST TEMP TRENDS... AS WELL AS THE
LINGERING LOWER CLOUDS IN THE NW CWA AND PLENTY OF FILTERED SUNSHINE
ELSEWHERE... SUPPORT HIGHS FROM 65 NW RANGING TO 76 SOUTHEAST.
(TODAY`S RECORD HIGH IS 75 AT RDU IN 1939... 74 IN GSO IN 1922...
AND 79 IN FAY IN 1956.) -GIH
TONIGHT...LOW LEVEL JET INCREASES IN RESPONSE TO THE APPROACH OF A
SIGNIFICANT S/W CROSSING THE UPPER MID WEST INTO THE GREAT LAKES.
WHILE SHOULD SEE SFC WINDS INCREASE TO AROUND 15 MPH AFTER
MIDNIGHT...DO NOT THINK THAT WE WILL BE ABLE TO TAP INTO THE
STRONGER WINDS JUST OFF THE SURFACE DUE TO A SFC BASED STABLE LAYER.
THE WELL MIXED AIR MASS ALONG WITH THE OVERCAST STRATUS DECK WILL
LEAD TO A MILD OVERNIGHT WITH TEMPS EITHER HOLDING STEADY OR SLOWLY
RISING. ANY SHOWERS THAT OCCUR SHOULD BE ISOLATED AND MAINLY
CONFINED TO THE YADKIN RIVER VALLEY. SHOULD SEE AN INCREASE IN
SHOWER COVERAGE HOWEVER TOWARD DAYBREAK IN THE FAR NW PIEDMONT AS A
STRONG COLD FRONT ASSOCIATED WITH THE GREAT LAKES S/W APPROACHES.
MIN TEMPS UPPER 50S TO AROUND 60. -WSS
FRIDAY DISCUSSION TO BE UPDATED SHORTLY...
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 240 PM THURSDAY...
VERY BROAD CYCLONIC FLOW ALOFT WILL ENCOMPASS MOST OF THE CONUS THIS
WEEKEND...TRANSITIONING TO A SPLIT FLOW PATTERN OVER THE WESTERN US
BY EARLY NEXT WEEK. IN THE WAKE OF THE DEPARTING COLD FRONT FRIDAY
NIGHT...A WELL MODIFIED HIGH PRESSURE WILL BUILD QUICKLY ACROSS THE
SOUTHEAST US ON SATURDAY AND THEN OFFSHORE BY SUNDAY....WITH THE
WEST-SOUTHWESTERLY FLOW ALOFT SUPPLYING PERIODS OF HIGH CLOUDS.
THIS WILL BRING SLIGHTLY COOLER BUT STILL ABOVE NORMAL HIGHS IN THE
60S FOR BOTH SATURDAY AND SUNDAY. ENERGY MOVING ACROSS THE DEEP
SOUTH ON SUNDAY WILL BRING MOISTURE BACK TOWARD THE CAROLINAS BY
LATE SUNDAY...BUT MOST MODELS CONTINUE TO INDICATE PRECIP WILL STAY
SOUTH OF NC...WITH A MOSTLY DRY COLD FRONT TO PUSH THROUGH FROM THE
NORTHWEST SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 240 PM THURSDAY...
A SPLIT FLOW PATTERN OVER THE WESTERN US WILL INHERENTLY LEAD TO
UNCERTAINTY IN THE FORECAST NEXT WEEK...THOUGH THERE IS GENERAL
MODEL AGREEMENT THAT THE LONGWAVE PATTERN WILL AMPLIFY AND A DEEPER
TROUGH WILL DEVELOP OVER THE EASTERN US. DURING THIS TIME...ENERGY
MOVING OUT OF A AN UPPER LOW OVER THE NORTHERN PACIFIC AND THROUGH
THE SOUTHERN STREAM WILL TRACK ACROSS THE SOUTHERN US...WHILE
SHORTWAVES ROTATE AROUND THE PERSISTENT UPPER LOW OVER EASTERN
CANADA. THE TEMPERATURE TREND FOR THE WEEK WILL BE BACK TO BELOW
NORMAL...THOUGH NOT NEARLY AS COLD AT OUR LATITUDE AS WE HAVE SEEN
OVER THE PAST FEW WEEKS. MODELS INDICATE ANOTHER ROUND OF MOISTURE
AND PRECIP SPREADING ACROSS THE SOUTHEAST US BY TUESDAY....WITH A
COLD FRONT TO PUSH THROUGH THE AREA BY WEDNESDAY. HOWEVER... WITHOUT
A STRONG SURFACE HIGH TO OUR NORTH...PTYPE IS EXPECTED TO BE ALL
LIQUID AT THIS TIME.
&&
.AVIATION /18Z WEDNESDAY THROUGH TUESDAY/...
AS OF 135 PM THURSDAY...
CURRENT VFR CONDITIONS ACROSS CENTRAL NC TERMINALS WILL PERSIST FOR
ANOTHER SEVERAL HOURS... LIKELY THROUGH SUNSET... AS A WARM FLOW
FROM THE SOUTHEAST AND SOUTH STEADILY STRENGTHENS TOWARD EVENING
(INT/GSO`S LIGHT WINDS FROM THE NE ARE EXPECTED TO SHIFT TO BE FROM
THE SE AND INCREASE TO NEAR 10 KTS AFTER 21Z). AFTER SUNSET... THIS
STRENGTHENING FLOW WILL BECOME UNIFORMLY FROM THE SOUTH (LIKELY 170-
200 DEGREES) INCREASING TO 14-19 KTS SUSTAINED WITH GUSTS TO 25-30
KTS POSSIBLE FROM MID EVENING ON THROUGH THE NIGHT AND INTO FRI
MORNING... AHEAD OF AN APPROACHING COLD FRONT. THIS INCREASING
SOUTHERLY FLOW WILL BRING A GOOD CHANCE OF LIFR CIGS OVERSPREADING
CENTRAL NC BETWEEN 02Z AND 05Z... ALTHOUGH THE WINDS SHOULD KEEP
VSBYS ABOVE 6SM. THESE LIFR CIGS ARE EXPECTED TO PERSIST THROUGH
SUNRISE FRI. THE COLD FRONT WILL CROSS CENTRAL NC DURING THE MORNING
THROUGH EARLY AFTERNOON... INT/GSO AROUND 14Z-15Z... RDU AROUND 16Z-
17Z... AND RWI/FAY LIKELY NOT UNTIL AFTER 18Z. WIDESPREAD SHOWERS
AND PERHAPS A STORM OR TWO WILL PRECEDE THE FRONT BY AN HOUR OR
TWO... LASTING A COUPLE OF HOURS. STRONG WINDS WILL SWING AROUND TO
SW AND WEST AND DIMINISH IMMEDIATELY BEHIND THE FRONT... WITH CIGS
RISING TO MVFR.
LOOKING BEYOND 18Z FRI: AS NOTED ABOVE... CIGS ARE EXPECTED TO RISE
BEHIND THE FRONT... TO VFR AT INT/GSO SOON AFTER 18Z... AT RDU SOON
AFTER 20Z... AND TO RWI/FAY SOON AFTER 22Z... WITH A SHIFT IN WINDS
TO WESTERLY UNDER 12 KTS. SURFACE HIGH PRESSURE WILL BUILD IN LATE
FRI THROUGH SUN BRINGING VFR CONDITIONS AND LIGHT WINDS DURING THIS
TIME FRAME. A MAINLY DRY COLD FRONT PASSAGE SUNDAY EVENING/NIGHT MAY
BRING BRIEF SUB-VFR CONDITIONS DURING THIS PERIOD... RETURNING TO
VFR MONDAY. INCREASING ONSHORE FLOW TUE MAY BRING SUB-VFR CONDITIONS
ONCE AGAIN LATE TUE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JB
NEAR TERM...HARTFIELD/WSS
SHORT TERM..SMITH
LONG TERM...SMITH
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
135 PM EST THU FEB 20 2014
.SYNOPSIS...HIGH PRESSURE OVER THE MID ATLANTIC WILL MOVE OFFSHORE
TODAY. A WARM FRONT WILL MOVE NORTH THROUGH THE REGION LATE THIS
AFTERNOON. A STRONG COLD FRONT WILL SWEEP EAST ACROSS THE AREA
FRIDAY. HIGH PRESSURE WILL BUILD INTO THE REGION FOR THE FIRST PART
OF THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM THURSDAY...
REST OF TODAY: ONLY SMALL CHANGES NEEDED TO THE EXISTING FORECAST.
THE DEW POINT DISCONTINUITY IS VERY APPARENT WITH VALUES RANGING
FROM THE MID 30S IN THE FAR NORTH (WHERE SURFACE WINDS ARE MORE
EASTERLY OR ENE) TO LOWER 50S IN THE SOUTH (WITH MORE SOUTHEASTERLY
SURFACE WINDS). THIS WARM FRONTAL ZONE IS EXPECTED TO TRANSLATE
NORTHWARD TODAY... ALBEIT WITH LITTLE FANFARE AS INCOMING PRECIP
WATER (ACCORDING TO BLENDED TPW IMAGERY) REMAINS BELOW ONE INCH WITH
CONSIDERABLE DRY AIR THROUGH THE COLUMN (ACCORDING TO UPSTREAM
SOUNDINGS AND RAP FORECAST SOUNDINGS) AND AN ABSENCE OF FORCING FOR
ASCENT. CONVECTION-ALLOWING MODELS PICK UP ON THE PATCHY SPRINKLES
IN THE FAR NW CWA BUT THESE ARE EXPECTED TO DRY UP AND HEAD TO OUR
NORTH IN THE NEXT COUPLE OF HOURS... RESULTING IN A POP-FREE
AFTERNOON AREAWIDE. THE LATEST TEMP TRENDS... AS WELL AS THE
LINGERING LOWER CLOUDS IN THE NW CWA AND PLENTY OF FILTERED SUNSHINE
ELSEWHERE... SUPPORT HIGHS FROM 65 NW RANGING TO 76 SOUTHEAST.
(TODAY`S RECORD HIGH IS 75 AT RDU IN 1939... 74 IN GSO IN 1922...
AND 79 IN FAY IN 1956.) -GIH
TONIGHT...LOW LEVEL JET INCREASES IN RESPONSE TO THE APPROACH OF A
SIGNIFICANT S/W CROSSING THE UPPER MID WEST INTO THE GREAT LAKES.
WHILE SHOULD SEE SFC WINDS INCREASE TO AROUND 15 MPH AFTER
MIDNIGHT...DO NOT THINK THAT WE WILL BE ABLE TO TAP INTO THE
STRONGER WINDS JUST OFF THE SURFACE DUE TO A SFC BASED STABLE LAYER.
THE WELL MIXED AIR MASS ALONG WITH THE OVERCAST STRATUS DECK WILL
LEAD TO A MILD OVERNIGHT WITH TEMPS EITHER HOLDING STEADY OR SLOWLY
RISING. ANY SHOWERS THAT OCCUR SHOULD BE ISOLATED AND MAINLY
CONFINED TO THE YADKIN RIVER VALLEY. SHOULD SEE AN INCREASE IN
SHOWER COVERAGE HOWEVER TOWARD DAYBREAK IN THE FAR NW PIEDMONT AS A
STRONG COLD FRONT ASSOCIATED WITH THE GREAT LAKES S/W APPROACHES.
MIN TEMPS UPPER 50S TO AROUND 60. -WSS
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 315 AM THURSDAY...
FRIDAY...SFC COLD FRONT PROJECTED TO MARCH EAST ACROSS CENTRAL NC
DURING THE MORNING THROUGH THE EARLY AFTERNOON HOURS. CONVERGENCE
ALONG THE BOUNDARY ALONG WITH A MOIST AIR MASS SHOULD RESULT IN A
BAND OF HEAVY SHOWERS. WILL SEE POTENTIAL FOR STRONG GUSTY SFC WINDS
TO OCCUR AHEAD OF THE BOUNDARY (NEAR 30KTS). EXPECT MAIN BAND OF
SHOWERS TO LIE ALONG THE U.S. 1 CORRIDOR BY LATE MORNING/MIND
DAY...AND INTO THE COASTAL PLAIN BY EARLY AFTERNOON. CONVECTIVE
PARAMETERS SUGGEST A HIGH SHEAR/LOW CAPE ENVIRONMENT WILL EXISTS
ALONG AND EAST OF HIGHWAY 1. THIS WILL LEAD TO THE DEVELOPMENT OF A
FEW THUNDERSTORMS IN THE LINE OF HEAVY SHOWERS. THIS MAY LEAD TO AN
INCREASE THREAT FOR DAMAGING WIND GUSTS AS THE SHOWERS AND STORMS
PROGRESS EAST INTO THE COASTAL PLAIN AND INTERACT WITH THE LOW LEVEL
JET. LOW LEVEL HELICITY VALUES SUPPORTIVE OF SOME WEAK ROTATION BUT
THE LACK OF A WELL-DEFINED SFC CIRCULATION IN OUR VICINITY WILL
LIMIT TORNADIC THREAT.
MAIN MID-UPPER LEVEL SUPPORT SWEEPS THROUGH THE COASTAL PLAIN BY MID
AFTERNOON...LEADING TO RAPID DISSIPATION/EXIT OF THE SHOWERS AND
STORMS. DOWNSLOPE FLOW IN THE WAKE OF THE SFC BOUNDARY COUPLED WITH
DECENT SUBSIDENCE IN THE WAKE OF THE MID-UPPER LEVEL TROUGH WILL
LEAD TO CLEARING SKIES IN THE WESTERN PIEDMONT BY EARLY
AFTERNOON...AND INTO THE TRIANGLE AREA AND NORTHEAST PIEDMONT BY MID-
LATE AFTERNOON.
MAX TEMPS FRIDAY DEPENDENT ON ARRIVAL TIME OF SHOWERS AND POSSIBLY
CLEARING IN THE AFTERNOON. MODEL GUIDANCE IN REASONABLE AGREEMENT
AND GENERALLY FOLLOWED. MAX TEMPS MID 60S NW TO LOWER 70S FAR EAST.
COOLER DRIER AIR WILL OVERSPREAD CENTRAL NC FRIDAY NIGHT AS HIGH
PRESSURE OVER THE LOWER MS VALLEY BUILDS EAST-NE. SFC WINDS WILL
SUBSIDE AND UNDER MAINLY CLEAR SKIES...SHOULD SEE TEMPS COOL BACK
INTO THE 30S BY EARLY SATURDAY.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 306 AM THURSDAY...
WITH THE FRONT OFFSHORE... HIGH PRESSURE WILL BRIEFLY BUILD ACROSS
THE AREA SATURDAY. A SIGNIFICANTLY DRIER AIRMASS ACROSS THE AREA
WILL BRING MOSTLY SUNNY SKIES. ON SUNDAY... WITH BROAD HIGH PRESSURE
OVER THE ATLANTIC AND A COLD FRONT APPROACHING FROM THE WEST... LOW
LEVEL SOUTHWEST FLOW WILL ENCOMPASS THE AREA... AND LOW LEVEL
THICKNESSES WILL RISE A OVER SATURDAY... PROVIDING SLIGHTLY WARMER
TEMPERATURES.
BROAD TROUGHING WILL BEGIN TO RE-ESTABLISH ITSELF ACROSS THE EAST
COAST TO BEGIN THE WEEK. A DRY COLD FRONT WILL MOVE THROUGH THE AREA
EARLY MONDAY... AND TEMPERATURES WILL FALL BACK A FEW DEGREES BELOW
NORMAL THROUGH THE FIRST PART OF THE WEEK. ANOTHER COLD FRONT LOOKS
LIKELY TO CROSS THE AREA WEDNESDAY... DROPPING TEMPERATURES AGAIN BY
A FEW DEGREES. GLOBAL MODELS DEVELOP A SURFACE WAVE ALONG THE
BAROCLINIC ZONE NEAR THE COAST. WILL CONTINUE WITH SLIGHT CHANCE
POPS THE LATTER HALF OF TUESDAY INTO EARLY WEDNESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH TUESDAY/...
AS OF 135 PM THURSDAY...
CURRENT VFR CONDITIONS ACROSS CENTRAL NC TERMINALS WILL PERSIST FOR
ANOTHER SEVERAL HOURS... LIKELY THROUGH SUNSET... AS A WARM FLOW
FROM THE SOUTHEAST AND SOUTH STEADILY STRENGTHENS TOWARD EVENING
(INT/GSO`S LIGHT WINDS FROM THE NE ARE EXPECTED TO SHIFT TO BE FROM
THE SE AND INCREASE TO NEAR 10 KTS AFTER 21Z). AFTER SUNSET... THIS
STRENGTHENING FLOW WILL BECOME UNIFORMLY FROM THE SOUTH (LIKELY 170-
200 DEGREES) INCREASING TO 14-19 KTS SUSTAINED WITH GUSTS TO 25-30
KTS POSSIBLE FROM MID EVENING ON THROUGH THE NIGHT AND INTO FRI
MORNING... AHEAD OF AN APPROACHING COLD FRONT. THIS INCREASING
SOUTHERLY FLOW WILL BRING A GOOD CHANCE OF LIFR CIGS OVERSPREADING
CENTRAL NC BETWEEN 02Z AND 05Z... ALTHOUGH THE WINDS SHOULD KEEP
VSBYS ABOVE 6SM. THESE LIFR CIGS ARE EXPECTED TO PERSIST THROUGH
SUNRISE FRI. THE COLD FRONT WILL CROSS CENTRAL NC DURING THE MORNING
THROUGH EARLY AFTERNOON... INT/GSO AROUND 14Z-15Z... RDU AROUND 16Z-
17Z... AND RWI/FAY LIKELY NOT UNTIL AFTER 18Z. WIDESPREAD SHOWERS
AND PERHAPS A STORM OR TWO WILL PRECEDE THE FRONT BY AN HOUR OR
TWO... LASTING A COUPLE OF HOURS. STRONG WINDS WILL SWING AROUND TO
SW AND WEST AND DIMINISH IMMEDIATELY BEHIND THE FRONT... WITH CIGS
RISING TO MVFR.
LOOKING BEYOND 18Z FRI: AS NOTED ABOVE... CIGS ARE EXPECTED TO RISE
BEHIND THE FRONT... TO VFR AT INT/GSO SOON AFTER 18Z... AT RDU SOON
AFTER 20Z... AND TO RWI/FAY SOON AFTER 22Z... WITH A SHIFT IN WINDS
TO WESTERLY UNDER 12 KTS. SURFACE HIGH PRESSURE WILL BUILD IN LATE
FRI THROUGH SUN BRINGING VFR CONDITIONS AND LIGHT WINDS DURING THIS
TIME FRAME. A MAINLY DRY COLD FRONT PASSAGE SUNDAY EVENING/NIGHT MAY
BRING BRIEF SUB-VFR CONDITIONS DURING THIS PERIOD... RETURNING TO
VFR MONDAY. INCREASING ONSHORE FLOW TUE MAY BRING SUB-VFR CONDITIONS
ONCE AGAIN LATE TUE. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JB
NEAR TERM...HARTFIELD/WSS
SHORT TERM..WSS
LONG TERM...SEC
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1259 PM EST THU FEB 20 2014
.SYNOPSIS...
WARM FRONT LIFTS NORTH TODAY. STRONG COLD FRONT TONIGHT. ANOTHER
SYSTEM MOVES THROUGH ON SUNDAY. SNOW MONDAY NIGHT INTO TUESDAY.
WINTER CONTINUES IN NEW WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAD TO ADJUST THE POPS WITH THE ONGOING CONVECTION. STILL PLAYING
THE THUNDER CARD ALTHOUGH IT APPEARS THE CELLS ARE TRANSFORMING
INTO LARGER AREA OF SHOWERS. SHOULD EXIT TO THE NORTH BY 17Z.
PREVIOUS DISCUSSION...
A WARM FRONT LIFTS NORTH THIS MORNING WITH BETTER CHANCES FOR RAIN
SHOWERS ACROSS SOUTHEAST OH...NORTHEAST KY...AND PORTIONS OF WV
ALONG THE OH RIVER. INCREASED POPS LIFTING WITH THE WARM FRONT TO
LIKELY...DIMINISHING AS SHOWERS MOVE NORTH.
MODELS INDICATE WIND FLOW WILL INCREASE FROM THE SOUTHWEST TO
60-70 KNOTS AT H85 AHEAD OF A COLD FRONT EXPECTED TO PASS TONIGHT.
SOME OF THESE STRONG WINDS WILL MOST LIKELY BE FELT OVER THE
HIGHER TERRAIN...AND ALONG SHOWERS WHICH WILL BE CAPABLE TO MIX
DOWN THESE WINDS. HOWEVER...IN THE WARM SECTOR IT WILL STRUGGLE
TO MIX DOWN PER UP GLIDING ASPECT EVIDENT IN ISENTROPIC SURFACES.
THE FRONT SHOULD PRODUCE A QUICK 0.5 INCHES OF RAIN...PERHAPS MORE
ALONG THE STRONGER STORM OR SHOWER.
HOLD OFF ON ISSUING A WIND ADVISORY AS THE EVENT LOOKS MARGINAL
ATTM. THE BEST WINDS 40 TO 50 KNOTS...OCCUR IN THE WARM SECTOR AS
EXPLAINED BEFORE. A WIND ADVISORY COULD BE NECESSARY ALONG OR
BEHIND THE FRONT. OR THE EVENT COULD BE TREATED WITH SPS AND
SEVERE STORM WARNINGS IF NEEDED. WILL LET DAY SHIFT TO DECIDE HOW
TO HANDLE THIS EVENT.
THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS TONIGHT WITH
DAMAGING WINDS BEING THE MAIN THREAT. SMALL HAIL CAN NOT BE RULED
OUT OF THE QUESTIONS AS FREEZING LEVELS WILL BE AROUND 9-10 KFT.
SNOW MELT HAVE CAUSE WATERS IN SMALL STREAMS TO RISE. FLOODING WAS
KEPT IN THE HAZARDOUS WEATHER OUTLOOK.
MINOR TWEAKS TO PREVIOUS TEMPERATURES. BLENDED THE RUC13 WITH MOST
GUIDANCE FOR TEMPERATURES THROUGH THE PERIOD.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
STRONG SYSTEM EXITING THE AREA AT THE OUTSET OF THE SHORT-TERM
PERIOD 12Z FRI. CONSENSUS OF NWP OUTPUT SLOWING THE FRONT JUST A BIT
OVERNIGHT FROM PREV RUNS...WITH THE VARIOUS MODELS HAVING THE SFC FRONT
LOCATED PRETTY MUCH ON OUR EASTERN CWA BORDER OF POCAHONTAS AND
RANDOLPH COUNTIES AT 12Z FRI. ELEVATED FRONT OF COURSE THEN IS A BIT
SLOWER AS WELL AND CROSSES THE HIGH PEAKS BTWN 12Z-15Z FRI MORNING
WITH A RAPID COOL DOWN FOR LOCATIONS SUCH AS SNO FROM THE LOW 40S AT
12Z FRI TO THE UPPER 20S/LOW 30S BY 15Z FRI. REFLECTED THIS IN THE
HOURLY TEMP TRACE FRIDAY MORNING. ALSO SLOWED DOWN PRECIP EXIT JUST
A BIT WITH IT...WITH LATEST NAM12 AND GFS BUFKIT SOUNDINGS STILL
INDICATING NEARLY COMPLETE SATURATION UP TO 600-500MB AT 15Z FRI.
THIS PRECIP WILL BE ALL RAIN INITIALLY ON THE HIGHEST PEAKS BUT WILL
QUICKLY CHANGE TO SNOW FOR A BRIEF WINDOW OF 1-3 HOURS AS THE PRECIP
MOVES OUT OF THE AREA. MAY GET A QUICK HALF-INCH TO PERHAPS AN INCH
OF SNOW FRI MID-MORNING AS THIS SYSTEM WINDS DOWN...BUT AGAIN THIS
SHOULD BE CONFINED TO ELEVATIONS MAINLY ABOVE 3KFT.
ONCE THE LAST OF THE PRECIP MOVES OUT...THE REMAINDER OF FRIDAY WILL
SEE IMPROVING CONDITIONS WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES BY
THE AFTERNOON HOURS WITH TEMPS INTO THE UPPER 40S TO LOWER 50S FOR
THE LOWLANDS. MAY SEE A BIT MORE STRATO-CU HANGING ON ACROSS THE
NORTHERN ZONES DURING THE AFTERNOON HOURS WITH A BIT MORE LLVL
MOISTURE TO WORK WITH. IT WILL CONTINUE TO BE A VERY WINDY DAY
ACROSS THE AREA WITH STRONG SFC LOW PRESSURE LOCATED OVER THE
NORTHERN GREAT LAKES. FOR THE LOWLANDS...EXPECT GENERAL 20G30KTS FOR
MUCH OF THE DAY...WHILE THE HIGHEST PEAKS OF THE EASTERN MOUNTAINS
SEE POTENTIALLY 40-45KT GUSTS. A 50KT GUST WOULD NOT BE IMPOSSIBLE
TO REALIZE AT THE HIGHEST ELEVATIONS...PARTICULARLY FOR AN HOUR OR
SO IMMEDIATELY FOLLOWING THE FRONTAL PASSAGE.
FRIDAY EVENING THE SFC LOW OVER THE GREAT LAKES CONTINUES TO SLOWLY
PULL AWAY WITH SFC HIGH PRESSURE LOCATED NEAR THE SMOKY MOUNTAIN
REGION BY 12Z SAT. DRY WEATHER WILL CONTINUE AND THE WORST OF THE
WINDY CONDITIONS WILL QUICKLY DISSIPATE NEAR AND AFTER SUNSET WITH
THE LOSS OF ANY MIXING. WITH A DECENT PRESSURE GRADIENT OVER THE
AREA WILL STILL MAINTAIN A PUFF OF WIND IT APPEARS. ALSO WILL SEE
SOME WARM ADVECTION MAKING INTO THE AREA BY AND AFTER 06Z SAT.
INHERITED MIN TEMPS FROM PREV SHIFT GENERALLY LOOK GOOD...WITH MINOR
ADJUSTMENTS.
SATURDAY WILL BE ANOTHER PLEASANT DAY. SFC HIGH PRESSURE SLOWLY
PULLS EAST WITH A RETURN S/SW FLOW SETTING UP BY THE AFTERNOON.
BUMPED UP MAX TEMPS FOR SATURDAY A GOOD 3-5 DEGREES AREA-WIDE WITH
925MB TEMPS PROGGED AROUND 8-9C...EXPECT TEMPS TO REBOUND INTO THE
MID 50S NORTHERN LOWLANDS AND UPPER 50S TO 60 CENTRAL AND SOUTHERN
LOWLANDS. IT WILL STILL BE ON THE BREEZY SIDE BUT NOT NEARLY AS
GUSTY AS FRIDAY...SO IT WILL PROBABLY FEEL MUCH NICER THAN FRIDAY.
SATURDAY NIGHT...INHERITED MINS THE LOW/MID 30S LOWLANDS STILL
APPEAR ON TRACK AGAIN...WITH JUST A FEW ADJUSTMENTS. A WEAK
DISTURBANCE IN THE NEAR ZONAL FLOW MAY DRAG A WEAK COLD FRONT INTO
THE NORTHERN ZONES BY END OF PERIOD AND THUS WILL CONTINUE THE
SLIGHT TO LOW CHANCE POPS FROM PREV SHIFT IN THESE AREAS.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
MODELS SHOWING A WEAK SYSTEM SYSTEM MOVING THROUGH SATURDAY NIGHT
INTO SUNDAY. TYPE OF PRECIPITATION IS QUESTIONABLE BASED ON TIMING
AND HOW MUCH RADIATION OCCURS SATURDAY NIGHT IN ADVANCE OF THE
SYSTEM. USED A BLEND OF THE ECMWF AND GFS.
FOR MONDAY THROUGH WEDNESDAY...USED A BLEND OF THE GEFS ENSEMBLE
MEAN AND ECMWF ENSEMBLE MEAN. THIS KEEPS A TROUGH OVER THE EASTERN
UNITED STATES CREATING A WINTER WEATHER SITUATION WHERE VARIOUS
WAVES COULD CREATE SNOW AT TIMES. THE TIMING OF THE WAVES AND
INTENSITY OF THE COLD AIR REMAIN IN QUESTION HOWEVER...AS VARIOUS
ENSEMBLE MEMBERS VARY CONSIDERABLY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AREA NOW IN THE WARM SECTOR AS WARM FRONTAL SHOWERS HAVE LIFTED
NORTH INTO PENNSYLVANIA AND CEILINGS GENERALLY ABOVE 7KFT. WITH THAT
SAID...CONCERNS TURN TO WIND FOR THE REMAINDER OF TODAY THROUGH
00Z FRIDAY.
MAINLY SOUTHERLY FLOW WILL CONTINUE TO BUILD TODAY SUSTAINED
15-20KTS WITH GUSTS TO 30KTS. THERE WILL BE A SLIGHT SOUTHEASTERLY
COMPONENT TO THIS FLOW AT FIRST AND WILL THEN VEER TO THE SOUTH
AHEAD OF THE EXPECTED COLD FRONT AND CONVECTION AFTER 00Z.
LOW LEVEL JET AT 850MB INCREASES OUT OF THE SOUTH SOUTHWEST WITH
THE APPROACH OF THE COLD FRONT. NAM FORECAST MODEL GIVING 60-70KTS
POSSIBLE WITH THIS FEATURE. CAN EXPECT SOME OF THIS MOMENTUM TO
MIX DOWN WITH SHOWERS AND THUNDERSTORMS...SO 40-50KT GUSTS IN THE
CONVECTION ITSELF ARE LIKELY.
EXPECTING A LINE OF CONVECTION TO FORM OUT AHEAD OF THE COLD FRONT
WHICH SHOULD BE A QUICK MOVER THROUGH THE CWA. FELT IT APPROPRIATE
TO CARRY IFR VISIBILITIES IN TSRA FOR ONE HOUR DURATION. TIMING
WILL BE CRITICAL TO THE FORECAST HOWEVER.
EXPECT CEILINGS TO RECOVER FAIRLY QUICKLY BEHIND THE FRONT WITH A
DRY SLOT WORKING IN. WINDS WILL VEER TO THE WEST SOUTHWEST BEHIND
THE FRONT WITH GUSTS IN THE 30-35KT RANGE POSSIBLE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF CONVECTION LINE AND FRONT MAY VARY
BY AN HOUR OR TWO. THIS COULD HAVE LARGE IMPACTS ON THE TAF GIVEN
THE SHORT DURATION OF THE CONVECTION.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H M
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H L L L L L L
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z FRIDAY...
IFR POSSIBLE IN SNOW LATE MONDAY NIGHT AND TUESDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/50
NEAR TERM...ARJ/26
SHORT TERM...50
LONG TERM...RPY
AVIATION...26
AREA FORECAST DISCUSSION
NWS NORMAN OK
1135 AM CST THU FEB 20 2014
.DISCUSSION...
THE 18Z AVIATION DISCUSSION FOLLOWS....
&&
.AVIATION...
STRONG NW WINDS WILL DIMINISH THIS AFTERNOON...AND BECOME LIGHT NW
THIS EVENING...THEN LIGHT SW OVERNIGHT...AS THE STRONG LOW
PRESSURE AREA RESPONSIBLE FOR THEM MOVES AWAY TO THE NE. BY
TOMORROW MORNING...HIGH PRESSURE OVER TX WILL SET UP A MODERATE
PRESSURE GRADIENT AGAIN...AND WINDS WILL INCREASE QUICKLY BY MID-
MORNING AS VERTICAL MIXING RESUMES. A FEW CLOUDS AROUND 2500-3500 FT
AGL WILL LAST A FEW MORE HOURS ACROSS N AND CENTRAL OK BEFORE
DISSIPATING LATE THIS AFTERNOON. EXPECT CLEAR SKIES TONIGHT...AND
JUST SOME HIGH CLOUDS TOMORROW. VISIBILITY RESTRICTIONS ARE NOT
EXPECTED THROUGH THE PERIOD...AS BLDU APPEARS TO HAVE DECREASED
SUBSTANTIALLY...AND IS NOT EXPECTED TO RESUME.
&&
.PREV DISCUSSION... /ISSUED 1037 AM CST THU FEB 20 2014/
UPDATE...
MINOR UPDATES TO THE FORECAST THIS MORNING INCLUDE REMOVAL OF
POPS ACROSS FAR NORTHERN OKLAHOMA. BATCH OF VERY LIGHT PRECIP HAS
MOVED NORTH INTO SRN KS...AND DONT EXPECT ANY FURTHER PRECIP HERE.
ALSO EXPANDED MENTION OF BLOWING DUST INTO PORTIONS OF NORTHERN
AND CENTRAL OKLAHOMA...AND WESTERN NORTH TEXAS. HIGH TEMPS WERE
TWEAKED TO REFLECT COOLER POST FRONTAL AIR ENTERING THE REGION.
EXPECT WINDS TO REMAIN ELEVATED THROUGH THE DAY...AND ONE OR TWO
MORE SEVERE WIND GUSTS MAY OCCUR BEFORE 3PM...MAINLY OVER FAR
NORTH CENTRAL OKLAHOMA. ELSEWHERE...EXPECT SUSTAINED 25 TO 35 MPH
WINDS WITH GUSTS OF 40 TO 45 MPH THROUGH MID AFTERNOON.
THEREAFTER...WINDS WILL GRADUALLY DECREASE IN SPEED THROUGH THIS
EVENING.
PREV DISCUSSION... /ISSUED 547 AM CST THU FEB 20 2014/
AVIATION...20 FEB 12Z TAF ISSUANCE...
MAJOR AVIATION CONCERN IS FOCUSED ON EXCESSIVE WINDS THIS MORNING
THROUGH THE EARLY AFTERNOON. CURRENTLY... WINDS ACROSS THE
PANHANDLES INTO SWRN KS ARE SUSTAINED 30 TO 40... GUSTING 45 TO
50 KTS. THESE STOUT WINDS WILL MOVE INTO NWRN OK THROUGH
SUNRISE... SPREADING E/SE ACROSS THE REGION THROUGH THE DAY AS THE
COLD FRONT CONTINUES ITS SURGE. WITH STRONG WINDS... BLOWING DIRT
WILL CAUSE VISIBILITY ISSUES AT AIRFIELDS ACROSS WRN AND CENTRAL
OKLAHOMA. EXPECT AIRFIELDS ACROSS WRN OK AND CENTRAL OK TO FLIRT
WITH MVFR VISIBILITIES THROUGH THE MORNING OFF AND ON DUE TO THE
BLOWING DIRT. LOW TO MID LEVEL STRATUS WILL CONTINUE TO STREAM TO
THE E/NE THIS MORNING... WITH ANY REMAINING MVFR CIGS ACROSS WRN
OK IMPROVING THROUGH THE MORNING AS THE FRONT MOVES IN. WINDS WILL
CALM EVER SO SLIGHTLY THROUGH THE AFTERNOON... CALMING AND BACKING
OUT OF THE SOUTHWEST OVERNIGHT THROUGH THE END OF THE PERIOD.
JTK
PREV DISCUSSION... /ISSUED 416 AM CST THU FEB 20 2014/
DISCUSSION...
PRIMARY FORECAST CONCERN REMAINS FOCUSED IN THE NEAR TERM... ON VERY
HIGH WINDS... ESPECIALLY ACROSS WRN AND NWRN OK... WHERE SUSTAINED
WINDS WILL REACH 40 MPH WITH GUSTS UP TO 60 ARE EXPECTED.
CURRENTLY... THROUGH 3 AM... ALREADY SEEING SUSTAINED WINDS OF 35-
40MPH IN THE PANHANDLE... WITH GUSTS 45-55. 09Z SFC ANALYSIS REVEALS
AN IMPRESSIVE 992MB SFC LOW TRAVERSING THE WRN OK/KS BORDER... WITH
A STOUT COLD FRONT EXTENDING FROM N/NE OF DODGE CITY S/SW ACROSS THE
PANHANDLES. RAP/NAM GUIDANCE HAS CONSISTENTLY PRODUCED 3HR PRES
CHANGE ALONG THE FRONT/SFC TROUGH OF 8 TO 10MB... ALONG WITH 0-1KM
LAPSE RATES OVER 7-8 C/KM. WITH HIGH CONFIDENCE FOR STRONG...
POTENTIALLY DAMAGING WINDS ACROSS NWRN OK... UPGRADED THE WIND
ADVISORY TO A HIGH WIND WARNING FOR PORTIONS OF NWRN OK... 40 MPH
SUSTAINED WITH GUSTS TO 60 MPH. BEST POTENTIAL FOR DAMAGING WIND
GUSTS WILL BE FROM NOW THROUGH MID/LATE MORNING.
WINDS WILL INCREASE ACROSS CENTRAL AND SRN OK AND WRN N TX THROUGH
THE MID TO LATE MORNING AS THE COLD FRONT CONTINUES TO TREK E/SE
ACROSS THE REGION. EXPECT THE COLD FRONT TO REACH THE OKC METRO SW
ALONG THE I-44 CORRIDOR NEAR NOON. SUSTAINED WINDS OF 30 TO 40
GUSTING 50 TO 55 MPH CAN BE EXPECTED THROUGH THE EARLY AFTERNOON.
MORNING COMMUTERS SHOULD TAKE CAUTION DRIVING THIS MORNING...
ESPECIALLY WHEN PILOTING A HIGH PROFILE VEHICLE ALONG E/W ROADS.
WIND GUSTS NEAR 60 MPH ARE CAPABLE OF MINOR DAMAGE TO TREES AND
POWER LINES. ALONG WITH STOUT WINDS... DRY AIR WILL FUNNEL IN ACROSS
THE REGION BEHIND THE FRONT. WITH THIS COMBINATION... ANY FIRES WILL
BURN OUT OF CONTROL QUICKLY... OUTSIDE BURNING IS HIGHLY DISCOURAGED
AND ANY FIRE WILL CAUSE A THREAT TO LIFE AND PROPERTY.
NORTH AND WEST OF THE SFC LOW... SOME ISOLATED -RA WILL CONTINUE TO
MOVE EWRD JUST NORTH OF THE OK/KS BORDER THIS MORNING. RECENT RUNS
OF THE HRRR AND NSSL WRF INDICATED SOME OF THIS ACTIVITY MAY DRIFT
SOUTH INTO FAR NRN OK. THIS IS A REASONABLE SCENARIO GIVEN THE
AVAILABLE MOISTURE AND RADAR TREND. WENT AHEAD AND STUCK SOME SLGT
CHC POPS ALONG THE NRN OK BORDER FOR THE MORNING HOURS.
WINDS WILL SLOWLY LESSEN THROUGH SUNSET FROM WEST TO EAST. REMAINING
WELL MIXED... TEMPS WILL COOL SLIGHTLY BEHIND THE FRONT... WITH AFTN
HIGHS IN THE MID 50S ACROSS NRN OK TO THE LOWER 60S ACROSS TEXOMA.
FOR FRIDAY... WINDS WILL QUICKLY BACK TO THE SW AS THE SFC HIGH
SLIDES TO TX GULF COAST. WINDS... ALTHOUGH NOT AS STRONG AS TODAY...
WILL INCREASE ONCE AGAIN. BUFR SOUNDINGS SHOW WRN N TX/SWRN OK
DRYING OUT AND MIXING QUICKLY BY THE AFTN. WITH BL FLOW OF 20 TO
30KTS... RH VALUES WILL DIP INTO THE LOWER 20S/UPPER TEENS FOR A FEW
HOURS IN THE AFTN. IN RESPONSE... VERY HIGH FIRE DANGER IS
ANTICIPATED FOR FRIDAY AS AFTN HIGHS CLIMB INTO THE MID TO UPPER 60S
AND SW WINDS ACROSS WRN OK/WRN N TX GUST INTO THE MID 20S.
BROAD TROUGHING WILL SET UP THROUGH SATURDAY WITH PSUEDO-ZONAL
FLOW ACROSS THE SRN PLAINS... S/SW SFC/BL FLOW WILL CONTINUE...
WITH WELL ABOVE AVG TEMPS PERSISTING. THE PATTERN WILL BEGIN TO
CHANGE LEADING INTO SUN... AS A WEAK H500 SHORT WAVE DEVELOPS OVER
THE ROCKIES... AND A COLD FRONT DROPS SWRD SUN MORNING. THIS IS
WHERE THE GFS/ECMWF SOLUTIONS START TO DIVERGE WITH REGARDS TO THE
SFC/BL. THE OVERALL SYNOPTIC PATTERN IS SIMILAR BTWN THE TWO...
BUT THE GFS IS MORE AGGRESSIVE WITH THE SFC HIGH SETTLING SWRD
INTO THE SRN PLAINS THROUGH MON. MEANWHILE THE ECMWF SETS UP GULF
RETURN FLOW...AND DEVELOPS SOME LIGHT QPF ACROSS CENTRAL AND ERN
OK. OF COURSE... THESE DIFFERENCES HAVE CREATED SOME CONFIDENCE
ISSUES WITH REGARDS TO TEMPS. GIVEN THE PATTERN... EXPECT A REGION
OF CANADIAN HIGH PRESSURE TO SLIDE S/SE ACROSS THE MIDWEST...
WITH TEMPS COOLING BACK AT OR NEAR NORMAL BY TUESDAY. TOOK A
CONSERVATIVE ROUTE WITH TEMPS... NOT GOING AS EXTREME AS THE
GFS...BUT A TAD COOLER THAN THE ECMWF... I GUESS YOU COULD SAY I
MADE A COMPROMISE. KEEP CHECKING BACK AS THE FORECAST FOR NEXT
WEEK BECOMES CLEARER.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 52 32 66 37 / 0 0 0 0
HOBART OK 53 31 64 35 / 0 0 0 0
WICHITA FALLS TX 58 34 69 39 / 0 0 0 0
GAGE OK 49 26 63 29 / 0 0 0 0
PONCA CITY OK 49 28 63 33 / 10 0 0 0
DURANT OK 68 38 66 41 / 10 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR OKZ005>008-
011>048-050>052.
TX...WIND ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR TXZ083>090.
&&
$$
84/23/23
AREA FORECAST DISCUSSION
NWS NORMAN OK
1037 AM CST THU FEB 20 2014
.UPDATE...
MINOR UPDATES TO THE FORECAST THIS MORNING INCLUDE REMOVAL OF
POPS ACROSS FAR NORTHERN OKLAHOMA. BATCH OF VERY LIGHT PRECIP HAS
MOVED NORTH INTO SRN KS...AND DONT EXPECT ANY FURTHER PRECIP HERE.
ALSO EXPANDED MENTION OF BLOWING DUST INTO PORTIONS OF NORTHERN
AND CENTRAL OKLAHOMA...AND WESTERN NORTH TEXAS. HIGH TEMPS WERE
TWEAKED TO REFLECT COOLER POST FRONTAL AIR ENTERING THE REGION.
EXPECT WINDS TO REMAIN ELEVATED THROUGH THE DAY...AND ONE OR TWO
MORE SEVERE WIND GUSTS MAY OCCUR BEFORE 3PM...MAINLY OVER FAR
NORTH CENTRAL OKLAHOMA. ELSEWHERE...EXPECT SUSTAINED 25 TO 35 MPH
WINDS WITH GUSTS OF 40 TO 45 MPH THROUGH MID AFTERNOON.
THEREAFTER...WINDS WILL GRADUALLY DECREASE IN SPEED THROUGH THIS
EVENING.
&&
.PREV DISCUSSION... /ISSUED 547 AM CST THU FEB 20 2014/
AVIATION...20 FEB 12Z TAF ISSUANCE...
MAJOR AVIATION CONCERN IS FOCUSED ON EXCESSIVE WINDS THIS MORNING
THROUGH THE EARLY AFTERNOON. CURRENTLY... WINDS ACROSS THE
PANHANDLES INTO SWRN KS ARE SUSTAINED 30 TO 40... GUSTING 45 TO
50 KTS. THESE STOUT WINDS WILL MOVE INTO NWRN OK THROUGH
SUNRISE... SPREADING E/SE ACROSS THE REGION THROUGH THE DAY AS THE
COLD FRONT CONTINUES ITS SURGE. WITH STRONG WINDS... BLOWING DIRT
WILL CAUSE VISIBILITY ISSUES AT AIRFIELDS ACROSS WRN AND CENTRAL
OKLAHOMA. EXPECT AIRFIELDS ACROSS WRN OK AND CENTRAL OK TO FLIRT
WITH MVFR VISIBILITIES THROUGH THE MORNING OFF AND ON DUE TO THE
BLOWING DIRT. LOW TO MID LEVEL STRATUS WILL CONTINUE TO STREAM TO
THE E/NE THIS MORNING... WITH ANY REMAINING MVFR CIGS ACROSS WRN
OK IMPROVING THROUGH THE MORNING AS THE FRONT MOVES IN. WINDS WILL
CALM EVER SO SLIGHTLY THROUGH THE AFTERNOON... CALMING AND BACKING
OUT OF THE SOUTHWEST OVERNIGHT THROUGH THE END OF THE PERIOD.
JTK
PREV DISCUSSION... /ISSUED 416 AM CST THU FEB 20 2014/
DISCUSSION...
PRIMARY FORECAST CONCERN REMAINS FOCUSED IN THE NEAR TERM... ON VERY
HIGH WINDS... ESPECIALLY ACROSS WRN AND NWRN OK... WHERE SUSTAINED
WINDS WILL REACH 40 MPH WITH GUSTS UP TO 60 ARE EXPECTED.
CURRENTLY... THROUGH 3 AM... ALREADY SEEING SUSTAINED WINDS OF 35-
40MPH IN THE PANHANDLE... WITH GUSTS 45-55. 09Z SFC ANALYSIS REVEALS
AN IMPRESSIVE 992MB SFC LOW TRAVERSING THE WRN OK/KS BORDER... WITH
A STOUT COLD FRONT EXTENDING FROM N/NE OF DODGE CITY S/SW ACROSS THE
PANHANDLES. RAP/NAM GUIDANCE HAS CONSISTENTLY PRODUCED 3HR PRES
CHANGE ALONG THE FRONT/SFC TROUGH OF 8 TO 10MB... ALONG WITH 0-1KM
LAPSE RATES OVER 7-8 C/KM. WITH HIGH CONFIDENCE FOR STRONG...
POTENTIALLY DAMAGING WINDS ACROSS NWRN OK... UPGRADED THE WIND
ADVISORY TO A HIGH WIND WARNING FOR PORTIONS OF NWRN OK... 40 MPH
SUSTAINED WITH GUSTS TO 60 MPH. BEST POTENTIAL FOR DAMAGING WIND
GUSTS WILL BE FROM NOW THROUGH MID/LATE MORNING.
WINDS WILL INCREASE ACROSS CENTRAL AND SRN OK AND WRN N TX THROUGH
THE MID TO LATE MORNING AS THE COLD FRONT CONTINUES TO TREK E/SE
ACROSS THE REGION. EXPECT THE COLD FRONT TO REACH THE OKC METRO SW
ALONG THE I-44 CORRIDOR NEAR NOON. SUSTAINED WINDS OF 30 TO 40
GUSTING 50 TO 55 MPH CAN BE EXPECTED THROUGH THE EARLY AFTERNOON.
MORNING COMMUTERS SHOULD TAKE CAUTION DRIVING THIS MORNING...
ESPECIALLY WHEN PILOTING A HIGH PROFILE VEHICLE ALONG E/W ROADS.
WIND GUSTS NEAR 60 MPH ARE CAPABLE OF MINOR DAMAGE TO TREES AND
POWER LINES. ALONG WITH STOUT WINDS... DRY AIR WILL FUNNEL IN ACROSS
THE REGION BEHIND THE FRONT. WITH THIS COMBINATION... ANY FIRES WILL
BURN OUT OF CONTROL QUICKLY... OUTSIDE BURNING IS HIGHLY DISCOURAGED
AND ANY FIRE WILL CAUSE A THREAT TO LIFE AND PROPERTY.
NORTH AND WEST OF THE SFC LOW... SOME ISOLATED -RA WILL CONTINUE TO
MOVE EWRD JUST NORTH OF THE OK/KS BORDER THIS MORNING. RECENT RUNS
OF THE HRRR AND NSSL WRF INDICATED SOME OF THIS ACTIVITY MAY DRIFT
SOUTH INTO FAR NRN OK. THIS IS A REASONABLE SCENARIO GIVEN THE
AVAILABLE MOISTURE AND RADAR TREND. WENT AHEAD AND STUCK SOME SLGT
CHC POPS ALONG THE NRN OK BORDER FOR THE MORNING HOURS.
WINDS WILL SLOWLY LESSEN THROUGH SUNSET FROM WEST TO EAST. REMAINING
WELL MIXED... TEMPS WILL COOL SLIGHTLY BEHIND THE FRONT... WITH AFTN
HIGHS IN THE MID 50S ACROSS NRN OK TO THE LOWER 60S ACROSS TEXOMA.
FOR FRIDAY... WINDS WILL QUICKLY BACK TO THE SW AS THE SFC HIGH
SLIDES TO TX GULF COAST. WINDS... ALTHOUGH NOT AS STRONG AS TODAY...
WILL INCREASE ONCE AGAIN. BUFR SOUNDINGS SHOW WRN N TX/SWRN OK
DRYING OUT AND MIXING QUICKLY BY THE AFTN. WITH BL FLOW OF 20 TO
30KTS... RH VALUES WILL DIP INTO THE LOWER 20S/UPPER TEENS FOR A FEW
HOURS IN THE AFTN. IN RESPONSE... VERY HIGH FIRE DANGER IS
ANTICIPATED FOR FRIDAY AS AFTN HIGHS CLIMB INTO THE MID TO UPPER 60S
AND SW WINDS ACROSS WRN OK/WRN N TX GUST INTO THE MID 20S.
BROAD TROUGHING WILL SET UP THROUGH SATURDAY WITH PSUEDO-ZONAL
FLOW ACROSS THE SRN PLAINS... S/SW SFC/BL FLOW WILL CONTINUE...
WITH WELL ABOVE AVG TEMPS PERSISTING. THE PATTERN WILL BEGIN TO
CHANGE LEADING INTO SUN... AS A WEAK H500 SHORT WAVE DEVELOPS OVER
THE ROCKIES... AND A COLD FRONT DROPS SWRD SUN MORNING. THIS IS
WHERE THE GFS/ECMWF SOLUTIONS START TO DIVERGE WITH REGARDS TO THE
SFC/BL. THE OVERALL SYNOPTIC PATTERN IS SIMILAR BTWN THE TWO...
BUT THE GFS IS MORE AGGRESSIVE WITH THE SFC HIGH SETTLING SWRD
INTO THE SRN PLAINS THROUGH MON. MEANWHILE THE ECMWF SETS UP GULF
RETURN FLOW...AND DEVELOPS SOME LIGHT QPF ACROSS CENTRAL AND ERN
OK. OF COURSE... THESE DIFFERENCES HAVE CREATED SOME CONFIDENCE
ISSUES WITH REGARDS TO TEMPS. GIVEN THE PATTERN... EXPECT A REGION
OF CANADIAN HIGH PRESSURE TO SLIDE S/SE ACROSS THE MIDWEST...
WITH TEMPS COOLING BACK AT OR NEAR NORMAL BY TUESDAY. TOOK A
CONSERVATIVE ROUTE WITH TEMPS... NOT GOING AS EXTREME AS THE
GFS...BUT A TAD COOLER THAN THE ECMWF... I GUESS YOU COULD SAY I
MADE A COMPROMISE. KEEP CHECKING BACK AS THE FORECAST FOR NEXT
WEEK BECOMES CLEARER.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 52 32 66 37 / 0 0 0 0
HOBART OK 53 31 64 35 / 0 0 0 0
WICHITA FALLS TX 58 34 69 39 / 0 0 0 0
GAGE OK 49 26 63 29 / 0 0 0 0
PONCA CITY OK 49 28 63 33 / 10 0 0 0
DURANT OK 68 38 66 41 / 10 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR OKZ008-013-
018>020-023>048-050>052.
HIGH WIND WARNING UNTIL 3 PM CST THIS AFTERNOON FOR OKZ004>007-
009>012-014>017-021-022.
TX...WIND ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR TXZ083>090.
&&
$$
84/23
AREA FORECAST DISCUSSION
NWS PORTLAND OR
928 AM PST THU FEB 20 2014
.SYNOPSIS...EXPECT A WET DAY TODAY IN THE LOWLANDS TODAY WITH PLENTY
OF SNOW IN THE CASCADES...AS A STALLED FRONTAL BOUNDARY KEEPS
PRECIPITATION AROUND THE FORECAST AREA. A SECONDARY DISTURBANCE WILL
MOVE ONSHORE ALONG THE BOUNDARY LATER TODAY...CAUSING STEADIER RAIN
IN THE VALLEYS BY AFTERNOON AND CONTINUED SNOW FOR THE CASCADE PASSES
AND ABOVE. PRECIPITATION WILL GRADUALLY DECREASE OVERNIGHT AS THIS
DISTURBANCE PUSHES EAST OF THE CASCADES AND HIGHER PRESSURE BUILDS
INTO THE PACIFIC NORTHWEST FRIDAY INTO THE WEEKEND. NORTHWEST FLOW
ALOFT MAY CAUSE SOME SHOWERS TO LINGER INTO THE WEEKEND ACROSS OUR
NORTHERN ZONES AS A COUPLE MORE DISTURBANCES BRUSH BY TO THE NORTH.
OTHERWISE THERE MAY BE SOME SUNBREAKS THIS WEEKEND...WITH THE BEST
CHANCE SOUTH AND OUTSIDE OF THE WILLAMETTE VALLEY. MODELS ARE SHOWING
A SYSTEM TRYING TO MOVE THROUGH THE RIDGE FOR SUNDAY NIGHT AND
MONDAY...WITH OCCASIONAL CHANCES OF PRECIPITATION CONTINUING NEXT
WEEK.
&&
.MORNING UPDATE...MADE NO CHANGES TO THE FORECAST THIS MORNING...WE
STILL LOOK ON TRACK FOR A RAINY DAY IN THE LOWLANDS WITH SNOW ABOVE
2500-3500 FEET. SO FAR SNOTEL/ODOT REPORTS INDICATE 2-6 INCHES OF
SNOW IN THE CASCADES OVERNIGHT...WITH WEBCAMS SHOWING STEADY LIGHT TO
MODERATE SNOW CONTINUING THIS MORNING. NEXT SHORTWAVE PRESENTLY
CROSSING 130W...SOMEWHAT VISIBLE ON SATELLITE IMAGERY BUT BETTER
DEFINED WITH THE RAP 850-700MB THETA-E ANALYSIS. AFTER A BRIEF LULL
EXPECT ISENTROPIC LIFT TO INCREASE AGAIN TODAY...CAUSING STEADY
VALLEY RAIN AND MTN SNOW TO INCREASE THROUGHOUT THE DAY BEFORE
TAPERING OFF THIS EVENING. OVERALL...CURRENT WINTER WX ADVISORIES
LOOK GOOD FOR THE CASCADES...THOUGH ACCUMULATIONS WILL PROBABLY BE
MARGINAL IN LANE COUNTY. WEAGLE
.SHORT TERM...TODAY THROUGH SATURDAY...THE WARM OR OCCLUDED FRONT
WITH THE SYSTEM WELL ADVERTISED BY THE MODELS HAS BEEN MOVING INTO
SOUTHWEST WASHINGTON AND NORTHWEST OREGON EARLY THIS MORNING...
MAINLY AFFECTING THE CENTRAL WILLAMETTE VALLEY NORTHWARD SO FAR. THE
MODELS SHOW THE TRAILING COLD FRONT WILL SLOWLY SAG INTO OUR
FORECAST AREA TODAY AND HELP SPREAD PRECIPITATION TO EVEN OUR
SOUTHERN FORECAST ZONES. THIS BOUNDARY THEN STALLS OVER THE OREGON
PORTION OF OUR AREA...WITH QUITE A FETCH OF MOISTURE UPSTREAM OVER
THE PACIFIC AS SEEN ON INFRARED SATELLITE IMAGERY THAT WILL RIDE
ALONG THE FRONT AND INTO OUR AREA TODAY. AS THE FRONT EASES IN...THE
NORTHERN SECTIONS...ESPECIALLY NORTH OF THE COLUMBIA RIVER WILL SEE
THE PRECIPITATION EASE LATER TODAY. THE PRECIPITATION WILL CONTINUE
IN THE OREGON SIDE OF THE FORECAST AREA INTO TONIGHT BEFORE
DECREASING LATER TONIGHT AND EARLY FRIDAY AS WELL.
HAVE MADE A FEW ADJUSTMENTS TO THE WINTER WEATHER ADVISORIES FOR
SNOW. IT APPEARS THE SOUTH WASHINGTON CASCADES SHOULD SEE THE SNOW
DIMINISH CONSIDERABLY BY 4 PM TODAY...SO HAVE MOVED UP THE ENDING
TIME OF THAT ADVISORY TO 4 PM. THE ADVISORY FOR THE NORTH OREGON
CASCADES REMAINS IN EFFECT UNTIL 10 PM TONIGHT. HAVE ISSUED A LOW
END ADVISORY FOR SNOW FOR THE LANE COUNTY CASCADES FROM LATE THIS
MORNING THROUGH MUCH OF TONIGHT AS THE FRONT SAGS INTO THE AREA AND
SNOW CONTINUES WELL INTO TONIGHT.
SNOW LEVELS WILL HOVER 2500 TO 3500 OR 4000 FEET...LOWEST IN THE
NORTH. THIS COULD BRING A LITTLE SNOW TO THE HIGHEST ELEVATIONS OF
THE CASCADE FOOTHILLS AS WELL...BUT BELIEVE AMOUNTS WILL STAY BELOW
ADVISORY CRITERIA AT THIS POINT.
THE UPPER FLOW TURNS MORE NORTHWESTERLY AND DRIES OUT LATER TONIGHT
AND FRIDAY...THOUGH THERE APPEARS ENOUGH ENERGY IN THE NORTHWEST FLOW
FOR A FEW SHOWERS THROUGH FRIDAY MAINLY AROUND THE HIGHER TERRAIN. IT
THEN LOOKS PRETTY DRY EXCEPT ANOTHER SHORT WAVE DROPS INTO WESTERN
WASHINGTON FROM THE NORTHWEST ON SATURDAY AND MAY CLIP MAINLY OUR
WASHINGTON ZONES...SO HAVE SOME LOW POPS FOR THAT. TOLLESON
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
SATURDAY NIGHT THROUGH WEDNESDAY...THE UPPER LEVEL RIDGE RESPONSIBLE
FOR THE DRYING TREND OVER THE WEEKEND SHOWS SIGNS OF BREAKING DOWN
TOWARD SUNDAY NIGHT OR MONDAY. 12Z ECMWF AND NOW 18Z GFS ARE COMING
IN LINE WITH THIS IDEA...THOUGH THEY BOTH TRY TO HANG ON TO SOME THIN
RIDGING LEFT OVER FROM A FAILED REX BLOCK OVER THE YUKON. THERE IS A
FAIR CHANCE THE REX BLOCK WILL DEVELOP AND HOLD...SO WILL KEEP POPS
BELOW CLIMO. HOWEVER WE DID BUMP THEM UP A TAD DUE TO THE MODELS
HINTING AT EITHER THE RIDGE BREAKING DOWN OR A PACIFIC STORM SYSTEM
UNDERCUTTING IT BY MIDWEEK. WEAGLE
&&
.AVIATION...STEADY LIGHT RAIN CONTINUES TODAY AS A FRONT SLOWLY
SAGS ACROSS THE AREA. CONDITIONS LIKELY REMAIN IN THE LOWER VFR
TO MVFR AT INLAND TAF SITES...WHILE COASTAL AREAS LIKELY REMAIN
IN THE MVFR TO IFR CATEGORY. EXPECT CONDITIONS TO SLOWLY IMPROVE
ACROSS THE AREA THIS AFTERNOON AND EVENING AS SHOWERS DECREASE.
MOUNTAINS FREQUENTLY OBSCURED IN CLOUDS AND PCPN THROUGH TONIGHT.
KPDX AND APPROACHES...VFR HOLDING THROUGH MOST OF THE DAY BUT
THERE IS ANOTHER BATCH OF RAIN ARRIVING LATER THIS MORNING THAT
COULD BRING SEVERAL HOURS OF MVFR CIGS.
&&
.MARINE...FRONTAL BOUNDARY WEAKENING ALONG WITH THE PRESSURE
GRADIENTS AND WILL LET ADVISORY FOR WIND EXPIRE. WEST SWELL WILL
BE SLOW TO DECAY...LIKELY REMAINING ABOVE 10 FT UNTIL FRIDAY
MORNING.
MUCH QUIETER CONDITIONS ARE EXPECTED FROM MIDDAY FRIDAY...AS HIGH
PRESSURE ESTABLISHES ITSELF INTO THE WEEKEND BRINGING LIGHTER
WINDS AND CONSIDERABLY LOWER SEAS THOUGH THE WEEKEND. A THERMAL
TROUGH WILL BE POSITIONED TO OUR SOUTH ALONG THE COAST WHICH MAY
INCREASE NORTHERLY WINDS IN THE SOUTHERN WATERS.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 PM PST THIS EVENING FOR
NORTHERN OREGON CASCADES.
WINTER WEATHER ADVISORY UNTIL 4 AM PST FRIDAY FOR CASCADES IN
LANE COUNTY.
WA...WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR SOUTH
WASHINGTON CASCADES.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PST
FRIDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA
TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER
BAR UNTIL 10 PM PST THIS EVENING.
&&
$$
MORE WEATHER INFORMATION ONLINE AT..
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
447 PM CST THU FEB 20 2014
.DISCUSSION...
UPDATED TO BREAK OUT LATE AFTERNOON GROUPING IN THE ZONE FORECAST
PRODUCT FOR GREATER CLARIFICATION FOR FORECAST THROUGH LATE
AFTERNOON HOURS AND FOR TONIGHT.
&&
.PREV DISCUSSION.../ISSUED 348 PM CST THU FEB 20 2014/
..POTENTIAL FOR SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT AS
STRONG COLD FRONT SWEEPS THROUGH...
SHORT TERM...AS OF 330 PM, THUNDERSTORMS WERE ALREADY DEVELOPING
OVER THE EXTREME NORTHWESTERN PART OF OUR CWA. INTERMEDIATE 20Z
OHX SOUNDING STILL SHOWED A WARM NOSE AROUND 700MB, AS DID THE
EARLIER 12Z SOUNDING. HOWEVER, FORECAST RUC SOUNDINGS CONTINUE TO
SUGGEST AN EROSION OF THE INHIBITING NOSE THROUGH OUR NORTHWESTERN
COUNTIES, AS INDICATED BY THE ONGOING THUNDERSTORMS.
RECORD WARMTH WAS RECORDED OVER THE MID STATE TODAY, WITH
NASHVILLE EQUALING A RECORD HIGH OF 78 DEGREES. WINDS CONTINUE TO
GUST TO BETWEEN 35 AND 40 MPH OVER OUR WESTERN COUNTIES, IN
ADVANCE OF THE STORMS.
A TORNADO WATCH IS IN EFFECT UNTIL 9PM FOR OUR MOST WESTERN
COUNTIES, AND IT WOULD NOT BE SURPRISING TO SEE SEVERE WEATHER
WATCHES EXTENDED INTO OTHER PARTS OF THE MID STATE LATER THIS
EVENING.
STILL LOOKS LIKE THE STRONG COLD FRONT, NOW LOCATED BACK OVER
SOUTHEASTERN MISSOURI, WILL SWEEP RAPIDLY EASTWARD ACROSS THE MID
STATE BETWEEN 00Z AND 06Z THIS EVENING, WITH AN ATTENDANT SQUALL
LINE, AND THE EXPECTATION FOR SOME DAMAGING STRAIGHT LINE WINDS,
LARGE HAIL, AND POSSIBLY A FEW TORNADOES AS WELL.
THERE WILL BE A SLIGHT CHANCE FOR LINGERING SHOWERS IN THE
MORNING, ALONG THE CUMBERLAND PLATEAU. OTHERWISE, TOMORROW SHOULD
BRING SOME DRIER AND MUCH QUIETER WEATHER, WITH AFTERNOON HIGHS
IN THE 50S.
UNSEASONABLY MILD TEMPERATURES REMAIN OVER THE UPCOMING WEEKEND,
WITH DAYTIME HIGHS FORECAST TO BE IN THE 60S BOTH SATURDAY AND
SUNDAY.
LONG TERM...A GENERAL COOL DOWN OCCURS NEXT WEEK, WITH HIGHS
FALLING TO THE 40S AND 50S MONDAY AND TUESDAY AND INTO THE 40S FOR
WEDNESDAY AND THURSDAY. HAVE TRENDED TOWARD THE COOLER ECMWF FOR
THE LATTER PERIODS, AS BOTH GFS AND ECMWF SUGGEST SOME PRETTY GOOD
DEEPENING OF UPPER TROUGH BY NEXT WEDNESDAY AND THURSDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 41 57 34 64 / 100 0 05 05
CLARKSVILLE 37 56 36 59 / 100 0 05 05
CROSSVILLE 39 51 32 59 / 100 20 05 05
COLUMBIA 40 57 34 65 / 100 0 05 05
LAWRENCEBURG 40 58 32 65 / 100 0 05 05
WAVERLY 39 57 35 62 / 100 0 05 05
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR TNZ009>011-029>034-
063>066-077>080.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR TNZ005>008-023>028-
056>062-075-093>095.
&&
$$
31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
348 PM CST THU FEB 20 2014
...POTENTIAL FOR SEVERE THUNDERSTORMS THIS EVENING AND TONIGHT AS
STRONG COLD FRONT SWEEPS THROUGH...
.SHORT TERM...AS OF 330 PM, THUNDERSTORMS WERE ALREADY DEVELOPING
OVER THE EXTREME NORTHWESTERN PART OF OUR CWA. INTERMEDIATE 20Z
OHX SOUNDING STILL SHOWED A WARM NOSE AROUND 700MB, AS DID THE
EARLIER 12Z SOUNDING. HOWEVER, FORECAST RUC SOUNDINGS CONTINUE TO
SUGGEST AN EROSION OF THE INHIBITING NOSE THROUGH OUR NORTHWESTERN
COUNTIES, AS INDICATED BY THE ONGOING THUNDERSTORMS.
RECORD WARMTH WAS RECORDED OVER THE MID STATE TODAY, WITH
NASHVILLE EQUALING A RECORD HIGH OF 78 DEGREES. WINDS CONTINUE TO
GUST TO BETWEEN 35 AND 40 MPH OVER OUR WESTERN COUNTIES, IN
ADVANCE OF THE STORMS.
A TORNADO WATCH IS IN EFFECT UNTIL 9PM FOR OUR MOST WESTERN
COUNTIES, AND IT WOULD NOT BE SURPRISING TO SEE SEVERE WEATHER
WATCHES EXTENDED INTO OTHER PARTS OF THE MID STATE LATER THIS
EVENING.
STILL LOOKS LIKE THE STRONG COLD FRONT, NOW LOCATED BACK OVER
SOUTHEASTERN MISSOURI, WILL SWEEP RAPIDLY EASTWARD ACROSS THE MID
STATE BETWEEN 00Z AND 06Z THIS EVENING, WITH AN ATTENDANT SQUALL
LINE, AND THE EXPECTATION FOR SOME DAMAGING STRAIGHT LINE WINDS,
LARGE HAIL, AND POSSIBLY A FEW TORNADOES AS WELL.
THERE WILL BE A SLIGHT CHANCE FOR LINGERING SHOWERS IN THE
MORNING, ALONG THE CUMBERLAND PLATEAU. OTHERWISE, TOMORROW SHOULD
BRING SOME DRIER AND MUCH QUIETER WEATHER, WITH AFTERNOON HIGHS
IN THE 50S.
UNSEASONABLY MILD TEMPERATURES REMAIN OVER THE UPCOMING WEEKEND,
WITH DAYTIME HIGHS FORECAST TO BE IN THE 60S BOTH SATURDAY AND
SUNDAY.
.LONG TERM...A GENERAL COOL DOWN OCCURS NEXT WEEK, WITH HIGHS
FALLING TO THE 40S AND 50S MONDAY AND TUESDAY AND INTO THE 40S FOR
WEDNESDAY AND THURSDAY. HAVE TRENDED TOWARD THE COOLER ECMWF FOR
THE LATTER PERIODS, AS BOTH GFS AND ECMWF SUGGEST SOME PRETTY GOOD
DEEPENING OF UPPER TROUGH BY NEXT WEDNESDAY AND THURSDAY.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR TNZ009>011-029>034-
063>066-077>080.
WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR TNZ005>008-023>028-
056>062-075-093>095.
&&
$$
19
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1139 AM CST THU FEB 20 2014
.UPDATE FOR AVIATION...
UPDATED FOR THE 18Z AVIATION DISCUSSION.
&&
.DISCUSSION... /ISSUED 1006 AM CST THU FEB 20 2014/
SKIES ARE MOSTLY CLOUDY ACROSS THE FORECAST AREA THIS MORNING
WITH TEMPERATURES FROM THE MID 60S TO LOWER 70S. SURFACE LOW
CURRENTLY NEAR KANSAS/MISSOURI BORDER WITH COLD FRONT EXTENDING
SOUTH FROM THE LOW THROUGH EASTERN OKLAHOMA AND INTO CENTRAL
TEXAS. THERE IS NOT MUCH IN THE WAY OF THUNDERSTORM DEVELOPMENT AT
THIS TIME BUT AS THE FRONT MOVES INTO WESTERN ARKANSAS
THUNDERSTORMS WILL BEGIN TO DEVELOP. WILL UPDATE FORECAST TO
REMOVE MORNING WORDING BUT NO BIG CHANGES ARE NEEDED AT THIS TIME.
ARS
PREV DISCUSSION... /ISSUED 557 AM CST THU FEB 20 2014/
A SIGNIFICANT COLD FRONT WILL BRING SEVERE WEATHER TO THE ENTIRE
MID-SOUTH THIS AFTERNOON AND INTO THIS EVENING...
SYNOPSIS...CURRENT GOES WATER VAPOR IMAGERY SHOWS A SIGNIFICANT
LONGWAVE TROUGH DIGGING ACROSS THE CENTRAL PLAINS THIS MORNING.
THIS TROUGH WILL CONTINUE TO DEEPEN AND ACQUIRE A NEGATIVE TILT AS
IT PUSHES INTO THE MID MISSISSIPPI VALLEY THIS AFTERNOON. LATEST
SURFACE ANALYIS SHOWS AN ASSOCIATED AND IMPRESSIVE 992MB DEEPENING
LOW PRESSURE SYSTEM LOCATED JUST TO THE NORTH OF THE OKLAHOMA
PANHANDLE. THIS SURFACE CYCLONE IS EXPECTED TO TRACK NORTHEAST
THROUGH NORTHERN MISSOURI THIS AFTERNOON...AND INTO THE
GREAT LAKES REGION BY THIS EVENING. SURFACE DEWPOINTS ACROSS THE
SOUTH RANGE FROM MID TO UPPER 50S TO MID 60S AS A WARM FRONT
CONTINUES TO PUSH NORTH. THIS SYSTEM IS EXPECTED TO BECOME
OCCLUDED JUST AS IT ARRIVES INTO THE MID-SOUTH. THIS ENVIRONMENT
WILL SET THE STAGE FOR A STRONG SQUALL LINE OF THUNDERSTORMS ALONG
THE COLD FRONT TO PUSH THROUGH THIS AFTERNOON INTO TONIGHT.
IN RESPECT TO TIMING AND THREATS...
THE INITIAL CONVECTIVE MODE IS EXPECTED TO BE MIXED AND THEN
TRANSITION INTO A LINEAR MODE BY 4 PM OR SO JUST AS IT ARRIVES AT
THE MISSISSIPPI RIVER.
PREDOMINANTLY WEST OF THE MISSISSIPPI RIVER...IN THE WARM SECTOR AHEAD
OF THE COLD FRONT...LATEST HRRR MODEL SHOWS SOME ISOLATED CELLS
FORMING BY EARLY AFTERNOON AS THE MODERATE UPPER LEVEL HEIGHT FALLS ARE
OCCURRING. WITH LATEST GUIDANCE SUGGESTING ABOUT 800-1000 J/KG
SBCAPE...60 KTS OF BULK SHEAR...AND A WEAK CAP IN PLACE
CONVECTION WILL INITIATE. THIS WILL ALLOW SOME ISOLATED CELLS TO
DEVELOP JUST AHEAD OF THE FRONT. SEMI-DISCREET SUPERCELLS AS WELL
AS SOME BOWING SEGMENTS WILL BE POSSIBLE. A FEW TORNADOES
ALONG WITH DAMAGING WINDS WILL BE THE PRIMARY THREAT.
BY LATE AFTERNOON ...THE COLD FRONT WILL CATCH UP TO THE PREFRONTAL
CONVECTION AND TRANSITION INTO A IMPRESSIVE QLCS (SQUALL LINE).
THIS IS WHEN DAMAGING WINDS WILL BECOME THE PRIMARY THREAT.
DAMAGING WINDS MAY BECOME WIDESPREAD EAST OF THE MISSISSIPPI RIVER
ALONG WITH A FEW SIGNIFICANT WIND GUSTS IN EXCESS OF 70MPH. AS THE
LINE MOVES EASTWARD...SOME EMBEDDED MESOVORTICES WITHIN THE QLCS
MAY POSE AN ISOLATED TORNADO RISK. ANY TORNADOES EMBEDDED WITHIN
THE LINE SHOULD BE SHORT TRACKED. THE SEVERE LINE SHOULD DEPART
EASTERN AREAS OF THE CWA BY LATE EVENING.
LONG TERM...FRIDAY THROUGH NEXT WEEK...
AFTER THE COLD FRONT MOVES THROUGH THIS EVENING...HIGH PRESSURE
WILL BUILD INTO THE REGION AND BRING A RETURN TO DRY WEATHER AND
CONTINUED MILD TEMPERATURES. THIS PLEASANT WEATHER SHOULD
CONTINUE FROM FRIDAY THROUGH THE FIRST HALF OF THE WEEKEND.
A COLD FRONT WILL MOVE THROUGH THE MID SOUTH ON SUNDAY BRINGING A
RETURN TO COOLER TEMPERATURES. DRY CONDITIONS SHOULD CONTINUE INTO
EARLY NEXT WEEK WITH TEMPERATURES RETURNING TO NEAR OR SLIGHTLY
BELOW AVERAGE. ANOTHER REINFORCING COLD FRONT WILL MOVE THROUGH ON
TUESDAY WITH LIGHT PRECIPITATION CHANCES AND COLDER TEMPERATURES.
AC3
&&
.AVIATION...
18Z TAF CYCLE
TIGHTENING PRESSURE GRADIENT AS LOW DEEPENS OVER MO AHEAD OF
ADVANCING COLD FRONT. THIS TRANSLATES INTO STRONG SOUTHERLY WINDS
CURRENTLY AT ALL TERMINALS AHEAD OF THE COLD FRONTAL PASSAGE.
SUSTAINED WINDS EXPECTED TO CONTINUE 20-25KT...WITH GUSTS POSSIBLE
BETWEEN 35-40 KTS.
PATCHY MVFR CIGS MAINLY BTN 2500-3000FT CONT AT MAINLY OVR THE NE
PORTION OF THE REGION WITH MORE BREAKS AND VFR TO THE SE. CIGS
SHOULD CONT TO LIFT SLOWLY UNTIL THUNDERSTORM ACTIVITY BEGINS TO
DEVELOP ALONG AND IN ADVANCE OF COLD FRONT.
STORMS HAVE RECENTLY BEGUN TO DEVELOP IN NE TX WHERE CAPPING IS A
BIT WEAKER. EXPECT THIS TREND TO CONTINUE...WITH STORMS DVLPG OVR AR
DURING THE 19-21Z RANGE. STORMS SHOULD CONSOLIDATE INTO A MORE
SOLID LINE BY LATE AFTERNOON...IMPACTING KMEM BETWEEN
20/21Z-21/00Z. THIS LINE WILL RACE EAST AND SHOULD IMPACT KMKL
BETWEEN 20/22Z-21/01Z AND KTUP BETWEEN 21/00Z-21/02Z. DAMAGING
WIND GUSTS WILL BE POSSIBLE...ESPECIALLY EAST OF THE MISSISSIPPI
RIVER. VSBYS MAY BE REDUCED TO IFR DURING ANY STRONG CONVECTION.
WINDS WILL SWITCH NORTHWESTERLY BEHIND THE CONVECTIVE LINE AND
BECOME MORE WESTERLY LATE TONIGHT AS SKIES EVENTUALLY
CLEAR. CLEAR SKIES AND WEST WINDS 5-10KT EXPECTED TO CONTINUE THRU
18Z FRI.
NGU
&&
.PRELIMINARY POINT TEMPS/POPS...
MEM 74 40 62 41 / 100 50 0 0
MKL 75 37 61 36 / 90 70 0 0
JBR 72 35 59 37 / 60 10 0 0
TUP 77 40 62 37 / 60 100 0 0
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE MS-
MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.
TN...WIND ADVISORY UNTIL 9 PM CST THIS EVENING FOR BENTON TN-CARROLL-
CHESTER-CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-HARDEMAN-
HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE-LAUDERDALE-MADISON-
MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY.
&&
$$