Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/26/15
AREA FORECAST DISCUSSION
NWS ALBANY NY
808 PM EDT WED MAR 25 2015
.SYNOPSIS...
A WARM FRONT APPROACHING FROM THE LOWER GREAT LAKES REGION AND OHIO
VALLEY WILL BRING SOME RAIN TO THE AREA INTO THE EVENING. AFTER A
BRIEF BREAK IN THE RAINFALL OVERNIGHT INTO EARLY THURSDAY...A LOW
PRESSURE SYSTEM AND ITS COLD FRONT WILL ALLOW FOR WIDESPREAD RAIN TO
DEVELOP BY THURSDAY AFTERNOON. AS THE COLD FRONT MOVES SOUTH OF THE
REGION...THE RAIN WILL MIX WITH THEN CHANGE TO SNOW OVER THE HIGHER
TERRAIN MAINLY NORTH AND WEST OF THE CAPITAL DISTRICT LATE THURSDAY
INTO THURSDAY EVENING. SOME LIGHT ACCUMULATING SNOW WILL BE POSSIBLE
FOR MOST HIGHER TERRAIN AREAS THURSDAY NIGHT. COLDER WEATHER WILL
ONCE AGAIN BE IN PLACE FOR FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 8 PM EDT...THE INITIAL BAND OF PRECIPITATION...IN THE FORM
OF RAIN/SLEET AND WET SNOW...HAS MOVED E OF THE REGION. IN ITS
WAKE...MORE SPOTTY PRECIP...MAINLY IN THE FORM OF LIGHT RAIN AND
DRIZZLE...PERSISTS ACROSS THE SOUTHERN ADIRONDACKS...MOHAWK
VALLEY...LAKE GEORGE SARATOGA REGION...AND INTO SW VT AND WESTERN
MA. SIGNIFICANT WET BULB COOLING HAS ALLOWED TEMPS TO SETTLE TO
AROUND FREEZING ACROSS PORTIONS OF THE WEST CENTRAL MOHAWK
VALLEY...SOUTHERN ADIRONDACKS...AS WELL AS FOR ELEVATIONS BETWEEN
ROUGHLY 1200-2000 FT ACROSS THE EASTERN CATSKILLS...SOUTHERN
VT...WESTERN MA...AND NW CT. IN THESE AREAS...HAVE ADDED MENTION
OF PATCHY FREEZING RAIN THROUGH THIS EVENING...WITH MAINLY LIGHT
RAIN/DRIZZLE ELSEWHERE.
RAINFALL SHOULD TAPER OFF BETWEEN 9 PM AND MIDNIGHT...PER LATEST
3KM HRRR AS THE BEST ISENTROPIC LIFT SHIFTS EAST INTO NEW ENGLAND.
LINGERING ISOLATED TO WIDELY SCATTERED SHOWERS WILL BE POSSIBLE
THEREAFTER MAINLY ACROSS NORTHERN AND SOUTHERN AREAS. MOST AREAS
WILL BE DRY AFTER MIDNIGHT. ALSO PATCHY FOG WILL
DEVELOP...ESPECIALLY FOR AREAS THAT HAVE A SNOWPACK.
AFTER THE INITIAL DROP IN TEMPS THIS EVENING DUE TO WET BULB
COOLING...TEMPS ARE EXPECTED TO HOLD STEADY...AND MAY EVEN RISE A
BIT AFTER MIDNIGHT DUE TO CONTINUED WEAK LOW LEVEL WARM ADVECTION.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
THURSDAY SHOULD START OUT DRY AS WE WILL BE BETWEEN
SYSTEMS...ALTHOUGH IT WILL LIKELY REMAIN MOSTLY CLOUDY WITH SOME
LINGERING PATCHY FOG INTO THE MORNING HOURS. THEN...RAIN WILL RE-
DEVELOP ACROSS THE AREA FROM MAINLY SOUTHWEST TO NORTHEAST AS A LOW
PRESSURE QUICKLY APPROACHES FROM THE OHIO VALLEY. ISENTROPIC LIFT ON
THE 290K SURFACE IS FORECAST TO INCREASE SUBSTANTIALLY BY EARLY
THURSDAY AFTERNOON WITH A STRENGTHENING SOUTH-SOUTHWEST FLOW ALOFT.
RAIN WILL BE MODERATE AT TIMES...WITH THE GREATER RAINFALL AMOUNTS
EXPECTED TO BE NORTH OF THE MID HUDSON VALLEY AND SOUTHWEST NEW
ENGLAND...AS THE TRACK OF THE CYCLONE CENTER SHOULD TRACK CLOSE TO
THAT REGION WITH THE BEST QPF NORTH AND WEST.
THERE IS STILL SOME DISAGREEMENT WITH REGARDS TO THE EXACT TRACK OF
THE LOW TOMORROW INTO THURSDAY NIGHT...ALTHOUGH MOST SOURCES OF
MODEL GUIDANCE HAVE TRENDED SLIGHTLY SOUTH OF PREVIOUS MODEL RUNS.
OUT OF THE 12Z GUIDANCE...THE NAM IS SHOWING THE FARTHEST SOUTH
TRACK WHICH ALSO RESULTS IN A COLDER SOLUTION AND MORE IN THE WAY OF
SNOW FOR AREAS NORTH AND WEST OF ALBANY. THE ECMWF/CMC ARE MORE
NORTHERLY AND WARMER...WHILE THE GFS IS SOMEWHERE IN BETWEEN. GIVEN
A BLEND OF SOLUTIONS LEANING TOWARDS THE GFS/ECMWF...THE THERMAL
PROFILE SHOULD BE WARM ENOUGH FOR ALL RAIN ACROSS MUCH OF THE AREA
THROUGH MOST OF THURSDAY. WILL MENTION A RAIN/SNOW MIX FOR THE
WESTERN ADIRONDACKS THURSDAY AFTERNOON...WITH RAIN/SNOW LINE
GRADUALLY SHIFTING SOUTH AND EAST THURSDAY EVENING AND NIGHT. AGAIN
WITHOUT GOOD MODEL AGREEMENT IT IS DIFFICULT TO PINPOINT SNOW
ACCUMULATIONS...BUT THE BEST POTENTIAL OF AT LEAST A FEW INCHES WILL
BE ACROSS THE HIGHER TERRAIN WEST OF THE HUDSON VALLEY LATE THURSDAY
INTO THURSDAY EVENING...AND THURSDAY NIGHT INTO THE SOUTHERN GREEN
MOUNTAINS. WILL CONTINUE TO MENTION POSSIBLE BORDERLINE ADVISORY
LEVEL SNOW IN THE HWO FOR THE WESTERN/SOUTHERN ADIRONDACKS.
HIGH TEMPERATURES THURSDAY ARE NOT EXPECTED TO BE AS WARM AS
PREVIOUS FORECASTS DUE TO A SLIGHTLY MORE SOUTHERLY TRACK TO THE
LOW. STILL...LOWER TO MID 40S WILL STILL BE LIKELY FOR MOST VALLEY
LOCATIONS WITH SOME UPPER 40S POSSIBLE SOUTH AND EAST OF ALBANY.
COLDER UPPER EXPECTED FOR THE ADIRONDACKS WITH COOLING INTO THE MID
30S POSSIBLE LATE IN THE DAY AS COLDER AIR STARTS TO WORK IN TO THE
NORTH AND WEST OF THE LOW AS IT TRACKS ACROSS SOUTHERN PORTIONS OF
THE REGION. WILL STILL MENTION A SLIGHT CHANCE OF THUNDER FOR FAR
SOUTHEAST AREAS DUE TO THE PRESENCE OF ELEVATED INSTABILITY. ICE
BREAKUP IS POSSIBLE MAINLY FOR SOUTHERN AREAS WITH RUNOFF LEADING TO
RIVER RISES. FLOODING IS NOT ANTICIPATED AT THIS TIME...ALTHOUGH
SITUATION WILL HAVE TO BE WATCHED. PLEASE SEE HYDRO SECTION FOR MORE
DETAILS.
TEMPERATURES WILL GRADUALLY COOL THURSDAY NIGHT FROM NORTHWEST TO
SOUTHEAST ACROSS THE REGION...WHICH COULD ALLOW FOR A RAIN/SNOW MIX
EVEN IN THE VALLEYS LATE THURSDAY NIGHT INTO EARLY FRIDAY MORNING.
THE SURFACE LOW IS FORECAST TO PULL AWAY FROM THE REGION ON
FRIDAY...HOWEVER AN UPPER LEVEL TROUGH IS FORECAST TO GRADUALLY
TRACK FROM THE GREAT LAKES INTO THE NORTHEAST FRIDAY INTO EARLY
SATURDAY. THIS WILL LEAD TO ISOLATED TO SCATTERED RAIN/SNOW SHOWERS
WITH MAINLY CLOUDY SKIES AND TEMPS BELOW NORMAL.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE LONG TERM PERIOD WILL GENERALLY FEATURE BELOW NORMAL TEMPS AND
PRECIPITATION. A FAST WEST/NORTHWEST FLOW ALOFT SHOULD DOMINATE
THROUGH THE PERIOD. WITHIN THIS FLOW...A COUPLE OF FAST MOVING
DISTURBANCES WILL BRING THE CHANCES OF SOME LIGHT PRECIPITATION.
INITIALLY...AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE REGION
SATURDAY. DEPENDING ON INDIVIDUAL DISTURBANCES EMBEDDED WITHIN THIS
TROUGH...AND ALSO THE POSSIBLE ORIENTATION OF AN INVERTED TROUGH
EXTENDING INTO SOUTHEAST PORTIONS OF THE REGION...SOME SNOW SHOWERS
OR SPOTTY LIGHT SNOW COULD AFFECT AREAS MAINLY S AND E OF
ALBANY...ESP SAT MORNING. WILL KEEP SLIGHT CHC TO LOW CHC POPS IN
THIS REGION. SOME MINOR ACCUMS COULD OCCUR ACROSS SOME HIGHER
TERRAIN OF THE SE CATSKILLS...SOUTHERN TACONICS...LITCHFIELD HILLS
AND SOUTHERN BERKSHIRES. OTHERWISE...CLEARING SKIES AND BELOW NORMAL
TEMPS ARE EXPECTED FOR LATER SAT INTO SUN. TEMPS ON SAT SHOULD ONLY
REACH THE 30S FOR VALLEYS...AND 20S ACROSS HIGHER ELEVATIONS. SAT NT-
SUN AM WILL BE QUITE COLD...WITH MIN TEMPS FALLING INTO THE TEENS
AND 20S FOR MOST VALLEYS...WITH SOME SINGLE DIGITS EXPECTED ACROSS
THE WESTERN ADIRONDACKS. ON SUNDAY...WITH MORE SUNSHINE AND THE
UPPER LEVEL TROUGH SHIFTING EAST OF THE REGION...EXPECT AFTERNOON
MAX TEMPS TO REACH THE LOWER/MID 40S IN VALLEYS...WITH MAINLY 30S
ACROSS HIGHER ELEVATIONS.
THEN...A FAST MOVING CLIPPER TYPE SYSTEM IS EXPECTED TO TRANSLATE
EAST ACROSS SE CANADA FOR SUN NT INTO MON. WARM ADVECTIVE PRECIP MAY
ALLOW FOR SNOW SHOWERS ACROSS NORTHERN AREAS LATE SUN NT...WITH
MAINLY RAIN SHOWERS FOR VALLEYS ON MON...AND RAIN/SNOW SHOWERS
ACROSS HIGHER TERRAIN. WINDS MAY BECOME QUITE GUSTY AT TIMES MON.
WITH THE LOW PASSING NORTH OF THE REGION...A LOW LEVEL SOUTHWEST
FLOW SHOULD ALLOW AFTERNOON TEMPS TO REACH THE 40S TO LOWER 50S IN
VALLEYS...WITH MAINLY 30S TO LOWER 40S ACROSS HIGHER ELEVATIONS.
WARMER MAX TEMPS COULD OCCUR SHOULD ANY PROLONGED BREAKS IN THE
CLOUDS DEVELOP...PARTICULARLY ACROSS PORTIONS OF THE MID HUDSON
VALLEY. FOR MON NT...TEMPS SHOULD COOL INTO THE 20S AND 30S...WITH
SOME LINGERING SNOW SHOWERS POSSIBLE ACROSS THE SOUTHERN ADIRONDACKS.
A RIDGE OF HIGH PRESSURE IS EXPECTED MOVE ACROSS THE REGION LATER
TUE INTO TUE NT...WHILE A FAST MOVING IMPULSE IS EXPECTED TO PASS
MAINLY SOUTH OF THE REGION. SOME LINGERING RAIN/SNOW SHOWERS COULD
AFFECT THE SOUTHERN ADIRONDACKS TUE MORNING...OTHERWISE GENERALLY
DRY FOR MOST OF THE REGION TUE AND TUE NT...ALTHOUGH WILL NEED TO
WATCH HOW FAR NORTH THE DISTURBANCE PASSING TO OUR SOUTH TRACKS IN
CASE SOME SHOWERS EXTEND INTO OUR REGION. TEMPS SHOULD REACH THE 40S
FOR MOST VALLEYS...PERHAPS LOWER 50S ACROSS THE MID HUDSON VALLEY ON
TUE...WITH MIN TEMPS TUE NT COOLING INTO THE 20S FOR HIGHER
ELEVATIONS...AND LOWER 30S IN VALLEYS.
THE NEXT FAST MOVING IMPULSE MAY AFFECT THE REGION BY WED...WITH
MORE SHOWERS. TEMPS ARE EXPECTED TO BE NEAR...OR A BIT BELOW
SEASONAL LEVELS.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
A WARM FRONT WILL APPROACH FROM THE SOUTHWEST TONIGHT. A COLD
FRONT WILL THEN SETTLE SOUTHEASTWARD DURING THURSDAY AFTERNOON AND
EVENING.
AN INITIAL SURGE OF PRECIPITATION WILL LINGER UNTIL AROUND 02Z-
04Z/THU ACROSS THE REGION. MOST OF THE PRECIP WILL BE RAIN...BUT A
FEW POCKETS OF SLEET AND WET SNOW COULD BE MIXED IN AT TIMES...ESP
AT KGFL AND KPSF.
LATER THIS EVENING THROUGH THE OVERNIGHT HOURS...LITTLE ADDITIONAL
PRECIP IS EXPECTED. HOWEVER...SOME LOW CLOUDS/FOG WILL BE
POSSIBLE. AT THIS TIME...EXPECT MVFR CIGS/VSBYS TO BECOME
WIDESPREAD. SOME IFR CONDITIONS COULD DEVELOP.
ON THU...AREAS OF MVFR/IFR WILL CONTINUE...WITH THE GREATEST
CHANCE OF IFR CONDITIONS LATER IN THE DAY. AS FOR RAINFALL...MUCH
OF THE MORNING SHOULD BE DRY...BUT SHOWERS AND/OR STEADY RAIN
SHOULD OVERSPREAD THE TAF SITES DURING THE AFTERNOON HOURS.
WINDS WILL BE SOUTH TO SOUTHWEST 8-15 KT THIS EVENING...WITH SOME
GUSTS OF 20-30 KT POSSIBLE AT KALB. WINDS WILL DECREASE LATER THIS
EVENING THROUGH THU MORNING...THEN TREND INTO THE WEST TO
NORTHWEST IN THE AFTERNOON AT 5-10 KT.
LOW LEVEL WIND SHEAR WILL REMAIN POSSIBLE FOR MUCH OF
TONIGHT...ESP IN AREAS WHERE SFC WINDS DECREASE UNDER 10 KT FROM
THE SOUTH...WHILE WINDS AROUND 2000 FT AGL REMAIN SOUTHWEST AT
35-40 KT.
OUTLOOK...
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE RA/SN.
FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE SHRA.
FRIDAY NIGHT-SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE SHSN.
SATURDAY-MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
FIRE WEATHER ISSUES ARE NOT ANTICIPATED OVER THE NEXT SEVERAL DAYS
WITH SNOW COVER IN PLACE ACROSS MUCH OF THE REGION...AND WET/
UNSETTLED WEATHER FORECAST INTO FRIDAY.
A WARM FRONT APPROACHING FROM THE LOWER GREAT LAKES REGION AND OHIO
VALLEY WILL BRING SOME RAIN TO THE AREA INTO THE EVENING. AFTER A
BRIEF BREAK IN THE RAINFALL OVERNIGHT INTO EARLY THURSDAY...A LOW
PRESSURE SYSTEM AND ITS COLD FRONT WILL ALLOW FOR WIDESPREAD RAIN TO
DEVELOP BY THURSDAY AFTERNOON. AS THE COLD FRONT MOVES SOUTH OF THE
REGION...THE RAIN WILL MIX WITH THEN CHANGE TO SNOW OVER THE HIGHER
TERRAIN MAINLY NORTH AND WEST OF THE CAPITAL DISTRICT LATE THURSDAY
INTO THURSDAY EVENING. SOME LIGHT ACCUMULATING SNOW WILL BE POSSIBLE
FOR MOST HIGHER TERRAIN AREAS THURSDAY NIGHT. COLDER WEATHER WILL
ONCE AGAIN BE IN PLACE FOR FRIDAY INTO THE WEEKEND.
&&
.HYDROLOGY...
WIDESPREAD HYDRO ISSUES ARE NOT EXPECTED THROUGH THE NEXT 5
DAYS...ALTHOUGH A FEW RIVER POINTS MAY GET CLOSE TO BANKFULL OVER
THE NEXT COUPLE DAY DUE TO RAINFALL AND SOME SNOWMELT. ALSO ISOLATED
ICE JAMS WILL BE POSSIBLE ACROSS THE SOUTHEAST HALF OF THE HYDRO
SERVICE AREA.
TONIGHT...TEMPERATURES WILL ONLY FALL INTO THE 30S. MOST LOCATIONS
WILL HOLD NEAR OR ABOVE 32 DEGREES. THIS WILL ALLOW SOME VERY MINOR
MELTING OF THE HYDRO SERVICE AREA SNOW PACK. THE SNOW PACK IS NOT
RIPE...AND IT IS VERY DEEP AND DENSE...ESPECIALLY ACROSS THE HIGHER
TERRAIN.
ON THURSDAY...MILDER AIR WITH DEWPOINTS CLIMBING INTO THE 40S MAINLY
SOUTH OF I-90... ALONG WITH RAINFALL IN THE HALF AN INCH TO ONE INCH
RANGE...WILL PRODUCE SOME MELTING OF THE SNOW...AND POTENTIALLY ICE
BREAKUP ON THE RIVERS.
THE LATEST MMEFS GUIDANCE INCLUDING THE NAEFS...GEFS...AND SREFS NOW
INDICATE NO RIVER POINTS FORECAST TO REACH FLOOD STAGE. THE LATEST
NERFC FORECASTS SHOW ABOUT 4 POINTS GETTING TO THE ALERT STAGE EAST
OF THE HUDSON RIVER VALLEY...BUT NO FLOODING AT THIS TIME.
CONFIDENCE CONTINUE BE LOW FOR THE POTENTIAL OF WIDESPREAD
FLOODING...SO NO WATCH HAS BEEN ISSUED AT THIS TIME.
THE MOST LIKELY TIME FRAME FOR ANY POTENTIAL PROBLEMS WOULD BE
THURSDAY EVENING FOR SMALL STREAMS...AND NOT UNTIL FRIDAY FOR THE
CRESTING OF THE BIGGER RIVERS. BY THAT TIME...TEMPERATURES ACROSS
THE ADIRONDACKS WILL BE AT OR BELOW FREEZING. NO SIGNIFICANT
PROBLEMS ARE EXPECTED ACROSS THE NORTHERN TIER OF THE HYDRO SERVICE
AREA...AS MUCH OF THE RAIN WILL SOAK OR BE ABSORBED INTO THE
SNOWFALL...AND THE RAIN WILL CHANGE TO SNOW LATE THURSDAY INTO
THURSDAY NIGHT.
THE POTENTIAL ALSO EXISTS FOR ISOLATED ICE JAMS THURSDAY INTO
FRIDAY...AS ICE BREAKS UP MAY OCCUR ON SOME RIVERS AND
STREAMS...PARTICULARLY FROM THE CAPITAL DISTRICT SOUTH AND EAST
WHERE ICE STILL EXISTS. THIS WILL BE MONITORED OVER THE NEXT COUPLE
OF DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...JPV/WASULA
NEAR TERM...KL/JPV
SHORT TERM...JPV
LONG TERM...KL
AVIATION...FRUGIS/KL
FIRE WEATHER...JPV/WASULA
HYDROLOGY...JPV/WASULA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
523 AM EDT TUE MAR 24 2015
.DISCUSSION...
A PREDOMINANT ZONAL MID/UPR LVL WIND PATTERN ACRS THE REGION WILL
PUSH AN H100-H70 ANTICYCLONE FROM THE DEEP SOUTH INTO THE MID ATLC
TODAY...THEN OFF THE CAROLINA COAST TONIGHT. ONCE IT DOES...IT WILL
BRIDGE A FRONTAL TROF DRAPED OVER THE FL PENINSULA...EVENTUALLY
MERGING WITH THE WRN EXTENSION OF THE ATLC RIDGE OVER THE GREATER
ANTILLES.
THE TRACK OF THE RIDGE WILL GENERATE A SHALLOW NERLY FLOW ACRS
CENTRAL FL THIS MRNG THAT WILL VEER SLOWLY TO THE E BY AFTN...THEN
TO THE SE OVERNIGHT. AT THE SAME TIME...THE ZONAL FLOW ALOFT WILL
PUSH A VERY STABLE SLUG OF H85-H70 AIR FROM THE NRN GOMEX INTO THE
FL PENINSULA...LATEST RUC ANALYSIS SHOWS LAPSE RATES THRU THE LYR
BTWN DROPPING FROM ARND 4.0C/KM OVERHEAD TO AS LOW AS 1.0C/KM S OF
APPALACHICOLA....H70 TEMPS BTWN 8-10C ENVELOP MOST OF THE GOMEX.
THIS WILL EFFECTIVELY CAP VERTICAL MOTION BLO 10KFT WHILE H100-H70
MEAN RH VALUES BLO 60PCT WORK THEIR WAY INTO THE CENTRAL PENINSULA.
ALOFT...RUC SHOWS LITTLE IN THE WAY OF MID LVL VORTICITY OVER THE
GOMEX REGION WHILE A DEPARTING H30-H20 JET STREAK E OF THE BAHAMA
BANK WILL KEEP CENTRAL FL UNDER ITS DESCENDING LEFT REAR QUAD.
WHILE NO SIG COOL AIR ADVECTION HAS OCCURRED BEHIND THE FROPA...AN
EXTENSIVE STRATUS DECK WILL BE SLOW TO BURN OFF AS THE MID LVL
THERMAL CAP PUSHES ACRS THE CENTRAL PENINSULA. A DVLPG ONSHORE FLOW
WILL FURTHER HELP KEEP TEMPS A FEW DEG COOLER THAN WHAT THE GFS MOS
GUIDANCE IS ADVERTISING. WILL GO WITH MAX TEMPS IN THE L/M80S
INTERIOR...M/U70S ALONG THE COAST. LIGHT ONSHORE FLOW OVERNIGHT WILL
KEEP MIN TEMPS IN THE L/M60S...PATCHY FOG IN THE PREDAWN HRS.
WED-THU...DEVELOPING SFC LOW HEADING TOWARD THE GREAT LAKES FROM THE
CENTRAL PLAINS WILL BUMP THE CENTER OF A RATHER LARGE AREA OF HIGH
PRESSURE OFF THE NEW ENGLAND COAST. AS A RESULT THE FLORIDA
PENINSULA WILL BECOME AWASH IN RETURN FLOW AS THE HIGH CENTER
REPOSITIONS SOUTHEAST OVER THE WESTERN ATLANTIC. THIS WILL PROMOTE A
STEADY RETURN OF MOISTURE AS LOCAL WINDS VEER SE-S WED...THEN S-SW
THU. MOISTURE SHOULD BE SUFFICIENT FOR LOCAL CIRCULATIONS AND
BREEZES TO PRODUCE SCT SHOWERS WITH BETTER CHANCES ALONG TREASURE
COAST AND VICINITY OF LAKE OKEECHOBEE WED THEN SPREADING NORTH FOR
THU. WARM WITH MAX TEMPS IN THE MID TO UPPER 80S.
FRI-MON...SIGNIFICANT UPPER TROUGH DIGS SOUTHWARD TO AID THE
PROGRESSION OF THE NEXT SYSTEM TO APPROACH PENINSULA BY FRIDAY.
SOME DYNAMIC VIGOR PRESENT ESPECIALLY WITH STOUT UPPER JET JUST
TO NORTH. CHANCE FOR STORMS NOTED WITH SOME PERHAPS BECOMING STRONG
AS COLD FRONT WITH PREFRONTAL TROUGH SWEEPS BY DURING DAY ON FRI
AND FRI EVENING. POST-FRONTAL COOLER MAX TEMPS BEHIND THE FRONT
FALL BACK IN TO THE 70S AND MINS IN 50S (EXCEPT SOME UPPER 40S
INTERIOR LAKE/VOLUSIA)...MODERATING LATE IN THE PERIOD.
&&
.AVIATION...THRU 25/12Z
SFC WINDS: THRU 24/16Z...N/NW 3-6KTS. BTWN 24/16Z-24/18Z...BCMG E/NE
6-9KTS CONTG THRU 25/03Z. AFT 25/03Z...E/SE AOB 5KTS.
VSBYS/WX: E OF KVRB-KOBE...THRU 24/14Z AREAS IFR/LCL LIFR IN BR/FG.
AFT 24/14Z...VFR ALL SITES CONTG THRU 25/08Z. AFT 25/08Z LCL MVFR BR.
CIGS: E OF KVRB-KOBE THRU 24/14Z PREVAILING VLFR BLO FL004...BTWN
24/14Z-24/16Z MVFR BTWN FL020-030...AFT 24/16Z VFR.
W OF KVRB-KOBE THRU 24/15Z PREVAILING IFR BTWN FL006-009...BTWN
24/15Z-24/18Z MVFR BTWN FL020-030...AFT 24/18Z VFR.
&&
.MARINE...
TODAY-TONIGHT...HI PRES BUILDING ACRS THE DEEP SOUTH WILL
GENERATE A GENTLE TO MODERATE E/NE BREEZE THRU THE DAY...BCMG A
MODERATE SE BREEZE OVERNIGHT AS THE RIDGE BUILDS OFF THE CAROLINA
COAST AND MERGES WITH A SECOND RIDGE AXIS OVER THE GREATER ANTILLES.
SEAS 2-4FT NEARSHORE AND 3-5FT OFFSHORE.
WED-THU...WINDS BECOME SE FOR WED AND CONTINUE TO VEER TO SW BY
THU GENERALLY 10-15 KNOTS AS CENTER OF HIGH PRESSURE RE-POSITIONS.
SEAS 3-4 FEET NEARSHORE AND 4-5 FEET OFFSHORE.
FRI-SAT...COLD FRONT APPROACHES ON FRI BRINGING INCREASING CHANCES
FOR SHOWERS AND STORMS. OFFSHORE WINDS FRI TURN/SURGE NW 15-20
KNOTS FRI NIGHT IN POST-FRONTAL MODE. CONDITIONS REACH CAUTIONARY
LEVELS NEARSHORE AND SCA OFFSHORE INTO SAT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 76 64 83 66 / 10 10 20 30
MCO 82 64 89 67 / 10 10 20 30
MLB 78 67 84 68 / 10 10 20 40
VRB 78 67 84 67 / 10 10 30 40
LEE 80 63 87 66 / 10 10 20 20
SFB 80 64 87 67 / 10 10 20 30
ORL 82 65 87 68 / 10 10 20 30
FPR 79 66 84 67 / 10 10 30 40
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...MB
LONG TERM....DS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
212 PM CDT TUE MAR 24 2015
.UPDATE...
1111 AM CDT
MADE MINOR ADJUSTMENT TO POP/WX TRENDS THROUGH THE
AFTERNOON...AS PRECIP TO THE WEST AND SOUTHWEST GRADUALLY
APPROACH. DELAYED THIS ARRIVAL TO MORE TOWARDS MID TO LATE
AFTERNOON AS PRECIP JUST TO THE SOUTH OF THE CWA SHIFTS EAST ALONG
MID LEVEL SHORTWAVE ENERGY...AND WITH PRECIP OVER SOUTHERN IOWA
DRIVEN BY A MORE VIGOROUS WAVE MOVES TOWARDS EASTERN IOWA. MOST
AREAS WONT LIKELY OBSERVE MORE WIDESPREAD PRECIP UNTIL LATER IN
THE EVENING AS LONGWAVE TROUGH HELPS PRECIP SHIELD REALLY EXPAND
NORTHWARD. SKIES THIS AFTERNOON WILL VARY FROM PARTLY CLOUDY TO
PARTLY SUNNY EARLY...BUT THEN BECOME CLOUDIER LATE THIS AFTERNOON
WITH THE ARRIVAL OF THICKER CLOUD SHIELD TO THE SOUTHWEST.
RODRIGUEZ
&&
.SHORT TERM...
249 AM CDT
THROUGH TONIGHT...
IR IMAGERY EARLY THIS MORNING INDICATED THE STRATUS LAYER HAS
PUSHED WEST OF THE CHICAGO AREA...HOWEVER A FEW POCKETS OF STRATUS
HAVE BEEN REDEVELOPING AND SLIDING ACROSS FAR NORTHEAST IL. TEMPS
ARE GENERALLY REMAINED IN THE UPR 20S EARLY THIS MORNING...WITH A
FEW LOCATIONS RADIATING INTO THE LOW 20S. A NARROW CHANNEL OF
CIRRUS WAS ALREADY STREAMING NORTHEAST FROM THE DEVELOPING
SHORTWAVE CURRENTLY CENTERED OVER THE CENTRAL PLAINS. THE GRADIENT
WILL REMAIN LIGHT THROUGH DAYBREAK...HOWEVER THE WEAK DIFFLUENT
FLOW WILL QUICKLY DISSIPATE AND MIXING WILL STEADILY INCREASE BY
MID-MORNING. GUIDANCE INDICATES SPEEDS THROUGH THE CHANNEL ARND
20KT.
THE MOIST AXIS DOES APPEAR TO BE SLIGHTLY SLOWER TO ARRIVE ACROSS
NORTHEAST IL UNTIL AFT 21Z...SO HAVE NUDGED TIMING BACK AN HOUR OR
TWO. COULD SEE PRECIP PUSHING INTO THE FAR SOUTHWEST CWFA ARND 18-
20Z...HOWEVER WITH THE WEAK DIFFLUENT FLOW LINGERING FURTHER
NORTH...THIS MAY HELP TO HOLD-OFF PRECIP UNTIL CLOSER TO 00Z. WITH A
STEADY CONVEYOR OF SLIGHTLY WARMER AIR ADVECTING NORTH THIS
AFTN...TEMPS ARE EXPECTED TO WARM TO ARND 40. THE CONCERN IS THAT
WITH THE FRESH SNOWPACK THIS MAY HOLD TEMPS DOWN A DEGREE OR TWO.
TONIGHT...
AS ELUDED TOO ABOVE...PRECIP WILL BE STEADILY INCREASING IN
COVERAGE THIS EVENING. BUT THE MAIN CONCERN FOR TONIGHT WILL
REVOLVE AROUND CONVECTION AND POSSIBLY SOME STRONGER EMBEDDED
THUNDERSTORMS. MID- LVL SHEAR IS IMPRESSIVE THIS EVENING...WITH
VALUES NEARING 40-50KTS. GIVEN THE RATHER MOIST PROFILE AND CLOUDY
ENVIRONMENT...CAPE VALUES WILL REMAIN MINIMAL. 0-3KM BULK SHEAR IS
EQUALLY IMPRESSIVE WITH THIS DYNAMIC NEGATIVELY TILTED SHORTWAVE
TONIGHT. THE SPC HAS THE AREAS SOUTH OF PONTIAC TO FOWLER IN A
MARGINAL RISK FOR SEVERE STORMS TONIGHT.
DEW POINTS WILL BE STEADILY INCREASING THIS EVENING AS WELL...AS
WARM AIR CONTINUES TO ADVECT NORTH. BY LATE THIS EVENING DEW POINTS
WILL BE APPROACHING THE LOW/MID 30S...AND POSSIBLY NEAR 40 ACROSS
THE FAR SOUTH. THEN OVERNIGHT DEW POINTS WILL CONTINUE TO RISE INTO
THE MID/UPR 30S NORTH...AND LOW 40S SOUTH. THIS SHOULD AID IN EATING
INTO THE SNOWPACK RATHER QUICKLY...COUPLED WITH THE RAIN AS WELL.
PWAT VALUES WILL BE NEARING 1 INCH LATE TONIGHT...AS THE MOISTURE
TRANSPORT CONTINUES TO FEED NORTH ACROSS THE FORECAST AREA. CURRENT
TRACK OF THE SHORTWAVE IS TO LIFT NORTHEAST ACROSS PONTIAC TO GARY
BY 9Z...WHICH SHUD HELP PUSH CONVECTIVE COVERAGE EAST/NORTHEAST BY
DAYBREAK WED.
BEACHLER
&&
.LONG TERM...
350 AM CDT
WEDNESDAY NIGHT THROUGH MONDAY...
THE MAIN STORY DURING THE LONGER TERM PERIOD WILL BE THE AMPLIFYING
UPPER LEVEL FLOW PATTERN ACROSS NORTH AMERICA. UPPER LEVEL RIDGING
IS FORECAST TO BUILD OVER THE WESTERN CONUS IN RESPONSE TO THE
PROGRESSION A SIGNIFICANT DISTURBANCE OVER THE NORTHERN
PACIFIC...AND THIS WILL ULTIMATELY DRIVE SIGNIFICANT HEIGHT FALLS
AND TROUGHING OVER THE THE EASTERN HALF OF THE CONUS. AS A
RESULT...EXPECT TO TRANSITION BACK TO A PERIOD OF MUCH BELOW AVERAGE
TEMPERATURES LATE THIS WEEK INTO THE FIRST HALF OF THE WEEKEND.
THE PERIOD WILL START OUT MILD ON WEDNESDAY FOLLOWING THE PASSAGE OF
THE TUESDAY NIGHT STORM SYSTEM. IT DOES APPEAR THAT CLOUD COVER
COULD LINGER DURING THE DAY ON WEDNESDAY...AND THIS COULD LIMIT THE
AMOUNT OF WARMING WE EXPERIENCE DURING THE DAY. HOWEVER...WITH THE
COLDER AIRMASS NOT ARRIVING ACROSS THE AREA UNTIL LATER WEDNESDAY
NIGHT TEMPERATURES SHOULD BE ABLE TO CLIMB TO...AT LEAST...NEAR 50
DEGREES. AREAS SOUTH OF INTERSTATE 80 STAND THE BEST CHANCES TO
CLIMB WELL INTO THE 50S.
AS A COLD FRONT BEGINS TO SHIFT ACROSS NORTHERN ILLINOIS WEDNESDAY
NIGHT A WEAK SURFACE WAVE OF LOW PRESSURE IS EXPECTED TO DEVELOP
OVER THE SOUTHERN PLAINS...BEFORE QUICKLY SHIFTING NORTHEASTWARD
ALONG THE FRONT INTO THURSDAY MORNING. INCREASING FGEN ALONG THIS
FRONTAL WAVE SHOULD RESULT IN PRECIPITATION DEVELOPMENT WEDNESDAY
NIGHT...PRIMARILY ACROSS MY EAST CENTRAL ILLINOIS AND NORTHWESTERN
INDIANA COUNTIES. THIS ACTIVITY WILL SHIFT TO THE SOUTH AND EAST OF
MY AREA BY EARLY THURSDAY MORNING AS THE COLD FRONT CONTINUES TO
SHIFT SOUTHEASTWARD. DRY BUT COOLER WEATHER IN THE LOW TO 40S IS
EXPECTED FOR THE DAY THURSDAY.
ANOTHER STRONGER PUSH OF COLD AIR WILL ARRIVE OVER THE AREA BY
THURSDAY NIGHT INTO FRIDAY AS YET ANOTHER COLD FRONT SHIFTS OVER THE
AREA. STEEPENING LOW LEVEL LAPSE RATES OVER LAKE MICHIGAN WITH THIS
COLD AIR MASS COULD EVEN RESULT IN SOME LAKE EFFECT SNOW SHOWERS
ACROSS NORTHEASTERN ILLINOIS AND NORTHWESTERN INDIANA INTO FRIDAY
MORNING...AND THIS ACTIVITY LOOKS AS THOUGH IT COULD BE COMPLIMENTED
BY ANOTHER UPPER LEVEL PV ANOMALY DIGGING INTO THE BASE OF THE UPPER
LEVEL TROUGH OVER THE AREA. IF THIS SCENARIO PANS OUT AS CURRENTLY
FORECAST...THERE COULD BE SOME MINOR SNOW ACCUMULATIONS ACROSS
PORTIONS OF THE AREA WITH THIS ACTIVITY INTO FRIDAY.
WITH THE HEART OF THE COLD AIR MASS EXPECTED TO BE OVERHEAD ON
FRIDAY...IT LOOKS TO BE THE COLDEST DAY. HIGH TEMPERATURES ARE
CURRENTLY ONLY FORECAST TO GET INTO THE LOWER TO MID 30S...WHICH IS
A GOOD 15 TO 20 DEGREES BELOW AVERAGE. SURFACE HIGH PRESSURE SHOULD
BECOME CENTERED OVER OR NEAR THE AREA BY LATE FRIDAY NIGHT...SO THIS
SHOULD ALLOW TEMPERATURES FRIDAY NIGHT TO DROP INTO THE TEENS
INTO SATURDAY MORNING OUTSIDE OF CHICAGO.
AFTER ANOTHER WELL BELOW AVERAGE DAY ON SATURDAY...THINGS LOOKS TO
WARM BACK UP BY SUNDAY SURFACE RIDGE SHIFTS OVER THE SOUTHEASTERN
CONUS. IT APPEARS THAT SUNDAY COULD END UP NOT ONLY BEING A WARMER
DAY...WITH HIGHS POTENTIALLY WARMING BACK UP NEAR OR JUST ABOVE
AVERAGE...BUT ALSO A VERY BREEZY DAY. FORECAST GUIDANCE SUGGESTS
THAT A POTENT CLIPPER SYSTEM WILL TRACK EAST-SOUTHEASTWARD OVER
SOUTHERN ONTARIO...WHICH COULD SET UP A SURFACE GRADIENT SUPPORTIVE
OF SOME STRONG SOUTHWESTERLY WINDS. IN ADDITION...THE INCREASING WARM
AIR ADVECTON REGIME OVER THE AREA COULD ALSO RESULT IN THE
DEVELOPMENT OF SOME LIGHT RAIN SHOWERS DURING THE DAY.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* EAST WINDS AT 10-15 KT BECOMING SOUTHEAST WITH GUSTS UP TO 20
KT THIS EVE.
* SCATTERED SHOWERS AROUND 01Z WITH STEADY RAINFALL AND MVFR
PSBLY IFR VSBY ARRIVING ARND 4Z.
* IFR OR LOWER CIGS EXPECTED WITH STEADY RAIN OVERNIGHT.
* LLWS THIS EVE AND OVERNIGHT.
* GUSTY SOUTHWEST TO WEST WINDS TOMORROW.
JEE
//DISCUSSION...UPDATED 18Z...
THE NEXT LOW IS OVER NORTHEAST OKLAHOMA AND IT WILL MOVE OVER
NORTHEAST IL LATE TONIGHT INTO EARLY WEDNESDAY MORNING. RIGHT NOW
CLOUD COVER IS HAMPERING MIXING WITH ONLY A FEW SITES SHOWING
GUSTS UP TO 20 KT. MAY SEE A FEW OCNL GUSTS AT THE EASTERN
TERMINALS LATE THIS AFTN.
GUIDANCE KEEPS PUSHING BACK THE ARRIVAL TIME OF PRECIP THIS
EVENING...SO DID THE SAME IN THE TAFS. EXPECTING AN AREA OF
SCATTERED SHOWERS TO QUICKLY PASS OVER THE TERMINALS THIS
EVENING...WITH A BREAK IN PRECIP PSBL IN THE LATE EVENING. MORE
WIDESPREAD AND HEAVIER RAIN MOVES IN CLOSER TO MIDNIGHT. THE COMBO
OF WARMER AIR...RAIN...AND SNOW WILL LIKELY RESULT IN LOW END MVFR
TO HIGH END IFR VSBY AND CIGS. SOUTH TO SOUTHEAST WINDS WILL BE
GUSTING TO UP TO 25 KT OVERNIGHT WITH LLWS FORMING AS WELL.
GUIDANCE FEATURES 50KT WINDS JUST 2000 FT OFF OF THE DECK. CIGS
LOWER TO LIFR EARLY WEDNESDAY MORNING.
FOR THUNDER...THE BEST PARAMETERS FOR THUNDER REMAIN SOUTH OF THE
TERMINALS SO KEPT THUNDER OUT OF THE TAFS. CANNOT RULE OUT AN
ISOLATED EMBEDDED THUNDERSTORM AROUND THE TERMINALS...BUT AM
THINKING THE THUNDERSTORMS WILL BE TOO ISOLATED TO TRY TO CAPTURE
IN THE TAFS RIGHT NOW. TEMPERATURES SHOULD ALSO BE ABOVE FREEZING
SO NOT EXPECTING ANY FREEZING OR MIXED PRECIP.
PRECIP COMES TO AN END AS THE LOW SHIFTS NE OF THE AREA AND WINDS
BACK TO SW WITH GUSTS UP TO 25 KT BY MID WEDNESDAY MORNING. HAVE
LIMITED CONFIDENCE IN HOW QUICKLY CIGS IMPROVE TO MVFR AND THEN
EVENTUALLY VFR...AND THEY COULD IMPROVE SLOWER THAN INDICATED IN
THE FORECAST.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN RAIN...MEDIUM-HIGH CONFIDENCE IN TIMING.
* MEDIUM CONFIDENCE MAJORITY OF TS FORMING SOUTH OF THE
TERMINALS...LOW CONFIDENCE IN COVERAGE OF TS.
* HIGH CONFIDENCE IN LOWER CIGS...MEDIUM CONFIDENCE IN TIMING AND
HOW LOW THEY WILL BE.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...WEST TO NORTHWEST WINDS. MAINLY VFR CONDS.
THURSDAY...CHANCE OF SNOW SHOWERS MAINLY IN THE EVENING. MVFR
POSSIBLE.
FRIDAY...SLIGHT CHANCE OF LIGHT SNOW EARLY. OTHERWISE PRIMARILY
VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF RAIN. PATCHY MVFR POSSIBLE.
MONDAY...VFR.
BEACHLER
&&
.MARINE...
212 PM CDT
GENERALLY LIGHT EAST SOUTHEAST WINDS IN PLACE THIS AFTERNOON AS
HIGH PRESSURE IS SITUATED JUST TO THE EAST OF THE LAKE. TWO
SYSTEMS WILL MOVE EAST AND NORTHEAST TOWARDS LAKE MICHIGAN TONIGHT
WITH THE SOUTHERN SYSTEM HELPING TO INCREASE WINDS TO AROUND 30 KT
THIS EVENING. THE STRONGEST WINDS WILL LIKELY BE ACROSS THE
SOUTHERN HALF OF THE LAKE THIS EVENING INTO EARLY WEDNESDAY AS
THIS SYSTEM MOVES THROUGH THE SOUTHERN HALF OF THE LAKE. BOTH THE
NEARSHORE AND OPEN WATERS WILL BOTH OBSERVE THESE 30 KT
WINDS...WITH A PERIOD OF GALE FORCE GUSTS TO 35 KT STILL POSSIBLE
AS WELL. HAVE NOT ISSUED ANY GALE HEADLINES AT THIS TIME WITH THE
PREVAILING CONDITIONS APPEARING TO BE AROUND 30 KT AND WITH THE
DURATION OF THESE GALE FORCE GUSTS LIKELY REMAINING IN THE 4-6
HOUR TIME FRAME...BUT WILL CONTINUE TO MAKE MENTION OF THIS
POSSIBILITY.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...7 PM TUESDAY TO 4 PM WEDNESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
110 PM CDT Tue Mar 24 2015
.UPDATE...
ISSUED AT 1038 AM CDT TUE MAR 24 2015
High pressure sliding east as another low develops over the Plains
and moves into the Midwest later this evening. For now, a frontal
boundary not making much progress northward up into the region.
Between the slower approach of the front and the persistent cloud
cover, have pulled down todays highs. Would like to bring them
down further, but sat imagery starting to show some holes here and
there...and any clearing in the afternoon hours may allow for some
warming...but the highs for today will definitely wait until the
end of the day...with temps steady or climbing through the
overnight hours.
&&
.SHORT TERM...(Today)
ISSUED AT 329 AM CDT TUE MAR 24 2015
A band of mid-level warm frontogenesis will advance into central IL
from the west this morning, causing rain showers to eventually
develop through the dry low level airmass. The leading edge of the
rain band will likely encounter areas with surface temps at or just
below freezing, but not sure how far south will freezing rain
affect. 08z obs show only Jacksonville and Lawrenceville above
freezing, while the remainder of our C and SE IL obs at or below
freezing. Will need to include a mention of freezing rain a bit
farther south this morning as a result. Road surface temps on IDOT
sites showing road temps ranging from 34 to as low as 31F. We could
see some slippery road conditions develop with this initial rain
falling on dry pavement. Air temperatures should rise above freezing
across the board by 15z/10am, so any icing would melt quickly.
However, any ice on initially dry roads can be very slippery.
Will follow the HRRR depiction of rain advancing eastward in a band
that matches the current radar trends rather closely. Likely and
categorical PoPs this morning will be confined to the western
counties where low level saturation will occur the soonest.
The band of warm F-gen will gradually shift north this afternoon,
giving the precip a northward push as well. Have kept likely PoPs
across the northern half of our area through the afternoon.
Instability params support elevated thunderstorms today, generally
in the southwest half of our forecast area.
High temps today will be held in check by the cool east-northeast
flow that will persist through the day. Most areas will see the
mid-upper 40s this afternoon.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 329 AM CDT TUE MAR 24 2015
Deepening surface low pressure currently at 1006 mb over the OK
panhandle to eject ne into the IL river valley over central IL by
06Z/1 am tonight and then to southern part of Lake MI by 12Z/7 am
Wed and swing a cold front through central and eastern IL overnight.
Showers likely ahead of this front along with chances of
thunderstorms. SPC has marginal risk over much of central IL
(excluding Knox, Stark and Marshall counties) with slight risk of
severe storms this evening across central and sw MO from St Louis
southwest. Lows tonight range from upper 30s to near 40F over IL
river valley to upper 40s and lower 50s in southeast IL.
Central IL to be in between weather systems during the day Wed as low
pressure passes ne of the Great Lakes and another surface low
pressure organizes over the southern plains. Isolated showers and
thunderstorms to be possible later Wed afternoon south of I-72.
Milder highs Wed mostly in the 60s, ranging from around 60F from
Peoria north to upper 60s and lower 70s in southeast IL. 1007 mb low
pressure to track ne into far southern IL by 06Z/1 AM Wed night and
up the Ohio river to near the OH/KY border by dawn Thu. Models have
trended further south with this low pressure track, and SPC has
shifted slight risk of severe storms Wed night south of our CWA with
marginal risk into southeast counties along and south of I-70. Heavy
rains of 1-1.5 inches possible south of I-70 Wed night while rain
chances taper off to 20-30% nw of the IL river. Lows Wed night range
from mid 30s over IL river valley to 40-45F in southeast IL from I-70
southeast.
Lingered a chance of rain showers in southeast IL Thu morning then
low pressure moves into south-central PA by midday Thu and far enough
way to end rain chances Thu afternoon. Much cooler highs Thu in the
mid to upper 40s central IL and near 50F southeast IL. Even colder
Friday with highs in the upper 30s and lower 40s, coolest from I-74
ne. Models have been consistent in digging strong upper level trof
into the eastern states Thu/Fri bringing in the very cool
temperatures. 1030 mb Canadian high pressure settles into the Great
Lakes region Fri night and Sat with clouds and winds decreasing and
continued cold temps. Lows Fri night in the low to mid 20s. Highs
Sat in the low to mid 40s.
A cutoff upper level low passes north of the Great Lakes Sunday
keeping best chances of precipitation north of central IL, though
did carry small chances of light rain showers Sunday. Milder highs
Sunday and Monday in the mid to upper 50s with west central IL
around 60F.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 100 PM CDT TUE MAR 24 2015
Quasi stationary boundary at the surface just south of Central
Illinois terminals slow to move this afternoon, delaying the onset
of the MVFR/IFR stratus deck in PIA BMI and CMI. SPI BKN012
now...DEC soon to follow suit. Showers moving along SPI to DEC
path as well, with more rain to the west. Afternoon showers and
thunderstorms late remaining possible, though coverage anticipated
to be rather sparse...keeping the mention to VC since the warm
sector of the approaching low is delayed until after sunset.
Tightening pressure gradient however, will result in some rather
gusty winds after sunset/before midnight gusting to 30kts...mainly
out of the SE. IFR through the overnight hours. Clearing in the
morning with the llvl moisture trapped/enhanced may be delayed
considerably and since the operational models are not clearing
until closer to 16-18z...am holding off mention of improvement
just yet.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Shimon
LONG TERM...07
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
110 PM CDT TUE MAR 24 2015
.UPDATE...
1111 AM CDT
MADE MINOR ADJUSTMENT TO POP/WX TRENDS THROUGH THE
AFTERNOON...AS PRECIP TO THE WEST AND SOUTHWEST GRADUALLY
APPROACH. DELAYED THIS ARRIVAL TO MORE TOWARDS MID TO LATE
AFTERNOON AS PRECIP JUST TO THE SOUTH OF THE CWA SHIFTS EAST ALONG
MID LEVEL SHORTWAVE ENERGY...AND WITH PRECIP OVER SOUTHERN IOWA
DRIVEN BY A MORE VIGOROUS WAVE MOVES TOWARDS EASTERN IOWA. MOST
AREAS WONT LIKELY OBSERVE MORE WIDESPREAD PRECIP UNTIL LATER IN
THE EVENING AS LONGWAVE TROUGH HELPS PRECIP SHIELD REALLY EXPAND
NORTHWARD. SKIES THIS AFTERNOON WILL VARY FROM PARTLY CLOUDY TO
PARTLY SUNNY EARLY...BUT THEN BECOME CLOUDIER LATE THIS AFTERNOON
WITH THE ARRIVAL OF THICKER CLOUD SHIELD TO THE SOUTHWEST.
RODRIGUEZ
&&
.SHORT TERM...
249 AM CDT
THROUGH TONIGHT...
IR IMAGERY EARLY THIS MORNING INDICATED THE STRATUS LAYER HAS
PUSHED WEST OF THE CHICAGO AREA...HOWEVER A FEW POCKETS OF STRATUS
HAVE BEEN REDEVELOPING AND SLIDING ACROSS FAR NORTHEAST IL. TEMPS
ARE GENERALLY REMAINED IN THE UPR 20S EARLY THIS MORNING...WITH A
FEW LOCATIONS RADIATING INTO THE LOW 20S. A NARROW CHANNEL OF
CIRRUS WAS ALREADY STREAMING NORTHEAST FROM THE DEVELOPING
SHORTWAVE CURRENTLY CENTERED OVER THE CENTRAL PLAINS. THE GRADIENT
WILL REMAIN LIGHT THROUGH DAYBREAK...HOWEVER THE WEAK DIFFLUENT
FLOW WILL QUICKLY DISSIPATE AND MIXING WILL STEADILY INCREASE BY
MID-MORNING. GUIDANCE INDICATES SPEEDS THROUGH THE CHANNEL ARND
20KT.
THE MOIST AXIS DOES APPEAR TO BE SLIGHTLY SLOWER TO ARRIVE ACROSS
NORTHEAST IL UNTIL AFT 21Z...SO HAVE NUDGED TIMING BACK AN HOUR OR
TWO. COULD SEE PRECIP PUSHING INTO THE FAR SOUTHWEST CWFA ARND 18-
20Z...HOWEVER WITH THE WEAK DIFFLUENT FLOW LINGERING FURTHER
NORTH...THIS MAY HELP TO HOLD-OFF PRECIP UNTIL CLOSER TO 00Z. WITH A
STEADY CONVEYOR OF SLIGHTLY WARMER AIR ADVECTING NORTH THIS
AFTN...TEMPS ARE EXPECTED TO WARM TO ARND 40. THE CONCERN IS THAT
WITH THE FRESH SNOWPACK THIS MAY HOLD TEMPS DOWN A DEGREE OR TWO.
TONIGHT...
AS ELUDED TOO ABOVE...PRECIP WILL BE STEADILY INCREASING IN
COVERAGE THIS EVENING. BUT THE MAIN CONCERN FOR TONIGHT WILL
REVOLVE AROUND CONVECTION AND POSSIBLY SOME STRONGER EMBEDDED
THUNDERSTORMS. MID- LVL SHEAR IS IMPRESSIVE THIS EVENING...WITH
VALUES NEARING 40-50KTS. GIVEN THE RATHER MOIST PROFILE AND CLOUDY
ENVIRONMENT...CAPE VALUES WILL REMAIN MINIMAL. 0-3KM BULK SHEAR IS
EQUALLY IMPRESSIVE WITH THIS DYNAMIC NEGATIVELY TILTED SHORTWAVE
TONIGHT. THE SPC HAS THE AREAS SOUTH OF PONTIAC TO FOWLER IN A
MARGINAL RISK FOR SEVERE STORMS TONIGHT.
DEW POINTS WILL BE STEADILY INCREASING THIS EVENING AS WELL...AS
WARM AIR CONTINUES TO ADVECT NORTH. BY LATE THIS EVENING DEW POINTS
WILL BE APPROACHING THE LOW/MID 30S...AND POSSIBLY NEAR 40 ACROSS
THE FAR SOUTH. THEN OVERNIGHT DEW POINTS WILL CONTINUE TO RISE INTO
THE MID/UPR 30S NORTH...AND LOW 40S SOUTH. THIS SHOULD AID IN EATING
INTO THE SNOWPACK RATHER QUICKLY...COUPLED WITH THE RAIN AS WELL.
PWAT VALUES WILL BE NEARING 1 INCH LATE TONIGHT...AS THE MOISTURE
TRANSPORT CONTINUES TO FEED NORTH ACROSS THE FORECAST AREA. CURRENT
TRACK OF THE SHORTWAVE IS TO LIFT NORTHEAST ACROSS PONTIAC TO GARY
BY 9Z...WHICH SHUD HELP PUSH CONVECTIVE COVERAGE EAST/NORTHEAST BY
DAYBREAK WED.
BEACHLER
&&
.LONG TERM...
350 AM CDT
WEDNESDAY NIGHT THROUGH MONDAY...
THE MAIN STORY DURING THE LONGER TERM PERIOD WILL BE THE AMPLIFYING
UPPER LEVEL FLOW PATTERN ACROSS NORTH AMERICA. UPPER LEVEL RIDGING
IS FORECAST TO BUILD OVER THE WESTERN CONUS IN RESPONSE TO THE
PROGRESSION A SIGNIFICANT DISTURBANCE OVER THE NORTHERN
PACIFIC...AND THIS WILL ULTIMATELY DRIVE SIGNIFICANT HEIGHT FALLS
AND TROUGHING OVER THE THE EASTERN HALF OF THE CONUS. AS A
RESULT...EXPECT TO TRANSITION BACK TO A PERIOD OF MUCH BELOW AVERAGE
TEMPERATURES LATE THIS WEEK INTO THE FIRST HALF OF THE WEEKEND.
THE PERIOD WILL START OUT MILD ON WEDNESDAY FOLLOWING THE PASSAGE OF
THE TUESDAY NIGHT STORM SYSTEM. IT DOES APPEAR THAT CLOUD COVER
COULD LINGER DURING THE DAY ON WEDNESDAY...AND THIS COULD LIMIT THE
AMOUNT OF WARMING WE EXPERIENCE DURING THE DAY. HOWEVER...WITH THE
COLDER AIRMASS NOT ARRIVING ACROSS THE AREA UNTIL LATER WEDNESDAY
NIGHT TEMPERATURES SHOULD BE ABLE TO CLIMB TO...AT LEAST...NEAR 50
DEGREES. AREAS SOUTH OF INTERSTATE 80 STAND THE BEST CHANCES TO
CLIMB WELL INTO THE 50S.
AS A COLD FRONT BEGINS TO SHIFT ACROSS NORTHERN ILLINOIS WEDNESDAY
NIGHT A WEAK SURFACE WAVE OF LOW PRESSURE IS EXPECTED TO DEVELOP
OVER THE SOUTHERN PLAINS...BEFORE QUICKLY SHIFTING NORTHEASTWARD
ALONG THE FRONT INTO THURSDAY MORNING. INCREASING FGEN ALONG THIS
FRONTAL WAVE SHOULD RESULT IN PRECIPITATION DEVELOPMENT WEDNESDAY
NIGHT...PRIMARILY ACROSS MY EAST CENTRAL ILLINOIS AND NORTHWESTERN
INDIANA COUNTIES. THIS ACTIVITY WILL SHIFT TO THE SOUTH AND EAST OF
MY AREA BY EARLY THURSDAY MORNING AS THE COLD FRONT CONTINUES TO
SHIFT SOUTHEASTWARD. DRY BUT COOLER WEATHER IN THE LOW TO 40S IS
EXPECTED FOR THE DAY THURSDAY.
ANOTHER STRONGER PUSH OF COLD AIR WILL ARRIVE OVER THE AREA BY
THURSDAY NIGHT INTO FRIDAY AS YET ANOTHER COLD FRONT SHIFTS OVER THE
AREA. STEEPENING LOW LEVEL LAPSE RATES OVER LAKE MICHIGAN WITH THIS
COLD AIR MASS COULD EVEN RESULT IN SOME LAKE EFFECT SNOW SHOWERS
ACROSS NORTHEASTERN ILLINOIS AND NORTHWESTERN INDIANA INTO FRIDAY
MORNING...AND THIS ACTIVITY LOOKS AS THOUGH IT COULD BE COMPLIMENTED
BY ANOTHER UPPER LEVEL PV ANOMALY DIGGING INTO THE BASE OF THE UPPER
LEVEL TROUGH OVER THE AREA. IF THIS SCENARIO PANS OUT AS CURRENTLY
FORECAST...THERE COULD BE SOME MINOR SNOW ACCUMULATIONS ACROSS
PORTIONS OF THE AREA WITH THIS ACTIVITY INTO FRIDAY.
WITH THE HEART OF THE COLD AIR MASS EXPECTED TO BE OVERHEAD ON
FRIDAY...IT LOOKS TO BE THE COLDEST DAY. HIGH TEMPERATURES ARE
CURRENTLY ONLY FORECAST TO GET INTO THE LOWER TO MID 30S...WHICH IS
A GOOD 15 TO 20 DEGREES BELOW AVERAGE. SURFACE HIGH PRESSURE SHOULD
BECOME CENTERED OVER OR NEAR THE AREA BY LATE FRIDAY NIGHT...SO THIS
SHOULD ALLOW TEMPERATURES FRIDAY NIGHT TO DROP INTO THE TEENS
INTO SATURDAY MORNING OUTSIDE OF CHICAGO.
AFTER ANOTHER WELL BELOW AVERAGE DAY ON SATURDAY...THINGS LOOKS TO
WARM BACK UP BY SUNDAY SURFACE RIDGE SHIFTS OVER THE SOUTHEASTERN
CONUS. IT APPEARS THAT SUNDAY COULD END UP NOT ONLY BEING A WARMER
DAY...WITH HIGHS POTENTIALLY WARMING BACK UP NEAR OR JUST ABOVE
AVERAGE...BUT ALSO A VERY BREEZY DAY. FORECAST GUIDANCE SUGGESTS
THAT A POTENT CLIPPER SYSTEM WILL TRACK EAST-SOUTHEASTWARD OVER
SOUTHERN ONTARIO...WHICH COULD SET UP A SURFACE GRADIENT SUPPORTIVE
OF SOME STRONG SOUTHWESTERLY WINDS. IN ADDITION...THE INCREASING WARM
AIR ADVECTON REGIME OVER THE AREA COULD ALSO RESULT IN THE
DEVELOPMENT OF SOME LIGHT RAIN SHOWERS DURING THE DAY.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* EAST WINDS AT 10-15 KT BECOMING SOUTHEAST WITH GUSTS UP TO 20
KT THIS EVE.
* SCATTERED SHOWERS AROUND 01Z WITH STEADY RAINFALL AND MVFR
PSBLY IFR VSBY ARRIVING ARND 4Z.
* IFR OR LOWER CIGS EXPECTED WITH STEADY RAIN OVERNIGHT.
* LLWS THIS EVE AND OVERNIGHT.
* GUSTY SOUTHWEST TO WEST WINDS TOMORROW.
JEE
//DISCUSSION...UPDATED 18Z...
THE NEXT LOW IS OVER NORTHEAST OKLAHOMA AND IT WILL MOVE OVER
NORTHEAST IL LATE TONIGHT INTO EARLY WEDNESDAY MORNING. RIGHT NOW
CLOUD COVER IS HAMPERING MIXING WITH ONLY A FEW SITES SHOWING
GUSTS UP TO 20 KT. MAY SEE A FEW OCNL GUSTS AT THE EASTERN
TERMINALS LATE THIS AFTN.
GUIDANCE KEEPS PUSHING BACK THE ARRIVAL TIME OF PRECIP THIS
EVENING...SO DID THE SAME IN THE TAFS. EXPECTING AN AREA OF
SCATTERED SHOWERS TO QUICKLY PASS OVER THE TERMINALS THIS
EVENING...WITH A BREAK IN PRECIP PSBL IN THE LATE EVENING. MORE
WIDESPREAD AND HEAVIER RAIN MOVES IN CLOSER TO MIDNIGHT. THE COMBO
OF WARMER AIR...RAIN...AND SNOW WILL LIKELY RESULT IN LOW END MVFR
TO HIGH END IFR VSBY AND CIGS. SOUTH TO SOUTHEAST WINDS WILL BE
GUSTING TO UP TO 25 KT OVERNIGHT WITH LLWS FORMING AS WELL.
GUIDANCE FEATURES 50KT WINDS JUST 2000 FT OFF OF THE DECK. CIGS
LOWER TO LIFR EARLY WEDNESDAY MORNING.
FOR THUNDER...THE BEST PARAMETERS FOR THUNDER REMAIN SOUTH OF THE
TERMINALS SO KEPT THUNDER OUT OF THE TAFS. CANNOT RULE OUT AN
ISOLATED EMBEDDED THUNDERSTORM AROUND THE TERMINALS...BUT AM
THINKING THE THUNDERSTORMS WILL BE TOO ISOLATED TO TRY TO CAPTURE
IN THE TAFS RIGHT NOW. TEMPERATURES SHOULD ALSO BE ABOVE FREEZING
SO NOT EXPECTING ANY FREEZING OR MIXED PRECIP.
PRECIP COMES TO AN END AS THE LOW SHIFTS NE OF THE AREA AND WINDS
BACK TO SW WITH GUSTS UP TO 25 KT BY MID WEDNESDAY MORNING. HAVE
LIMITED CONFIDENCE IN HOW QUICKLY CIGS IMPROVE TO MVFR AND THEN
EVENTUALLY VFR...AND THEY COULD IMPROVE SLOWER THAN INDICATED IN
THE FORECAST.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN RAIN...MEDIUM-HIGH CONFIDENCE IN TIMING.
* MEDIUM CONFIDENCE MAJORITY OF TS FORMING SOUTH OF THE
TERMINALS...LOW CONFIDENCE IN COVERAGE OF TS.
* HIGH CONFIDENCE IN LOWER CIGS...MEDIUM CONFIDENCE IN TIMING AND
HOW LOW THEY WILL BE.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...WEST TO NORTHWEST WINDS. MAINLY VFR CONDS.
THURSDAY...CHANCE OF SNOW SHOWERS MAINLY IN THE EVENING. MVFR
POSSIBLE.
FRIDAY...SLIGHT CHANCE OF LIGHT SNOW EARLY. OTHERWISE PRIMARILY
VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF RAIN. PATCHY MVFR POSSIBLE.
MONDAY...VFR.
BEACHLER
&&
.MARINE...
409 AM CDT
WINDS WILL BEGIN TO INCREASE OUT OF THE SOUTHEAST OVER SOUTHERN LAKE
MICHIGAN THIS EVENING AS AN AREA OF LOW PRESSURE MOVES TOWARDS
NORTHERN ILLINOIS. IT NOW APPEARS THAT THE SURFACE LOW WILL TAKE A
TRACK RIGHT ACROSS SOUTHERN LAKE MICHIGAN LATE TONIGHT INTO EARLY
WEDNESDAY MORNING. THEREFORE...AS THE LOW MOVES OVER THE
LAKE...WINDS WILL LIKELY BECOME LIGHT AND VARIABLE FOR SHORT
PERIOD OVER FAR SOUTHERN LAKE MICHIGAN. WEST SOUTHWESTERLY WINDS
WILL ENSURE AS THE LOW SHIFTS OVER LOWER MICHIGAN WEDNESDAY
MORNING. WIND SPEEDS COULD APPROACH 25 TO 30 KT DURING THE
MORNING...BUT WIND SPEEDS SHOULD BE ON A DIMINISHING TREND THROUGH
THE DAY.
A COLD FRONT WILL SHIFT DOWN THE LAKE WEDNESDAY NIGHT...RESULTING IN
A NORTHERLY WIND SHIFT FOR THURSDAY. WINDS SPEEDS SHOULD ALSO
INCREASE UP TO 25 TO 30 KT BY THURSDAY EVENING AS THE SURFACE
GRADIENT TIGHTENS AHEAD OF AN AREA OF HIGH PRESSURE SHIFTING
SOUTHEASTWARD OVER THE UPPER MIDWEST. THIS SURFACE HIGH IS EXPECTED
TO SHIFT SOUTHEASTWARD OVER NORTHEASTERN ILLINOIS SATURDAY
MORNING...THEN SHIFT OVER THE SOUTHEASTERN CONUS BY SUNDAY. IT
APPEARS THAT ANOTHER SIGNIFICANT SOUTHERLY WIND EVENT COULD SET UP
FOR SUNDAY AS A POTENTIAL STORM SYSTEM TRACKS ACROSS SOUTHERN
ONTARIO.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...7 PM TUESDAY TO 4 PM WEDNESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
110 PM CDT Tue Mar 24 2015
.UPDATE...
ISSUED AT 1038 AM CDT TUE MAR 24 2015
High pressure sliding east as another low develops over the Plains
and moves into the Midwest later this evening. For now, a frontal
boundary not making much progress northward up into the region.
Between the slower approach of the front and the persistent cloud
cover, have pulled down todays highs. Would like to bring them
down further, but sat imagery starting to show some holes here and
there...and any clearing in the afternoon hours may allow for some
warming...but the highs for today will definitely wait until the
end of the day...with temps steady or climbing through the
overnight hours.
&&
.SHORT TERM...(Today)
ISSUED AT 329 AM CDT TUE MAR 24 2015
A band of mid-level warm frontogenesis will advance into central IL
from the west this morning, causing rain showers to eventually
develop through the dry low level airmass. The leading edge of the
rain band will likely encounter areas with surface temps at or just
below freezing, but not sure how far south will freezing rain
affect. 08z obs show only Jacksonville and Lawrenceville above
freezing, while the remainder of our C and SE IL obs at or below
freezing. Will need to include a mention of freezing rain a bit
farther south this morning as a result. Road surface temps on IDOT
sites showing road temps ranging from 34 to as low as 31F. We could
see some slippery road conditions develop with this initial rain
falling on dry pavement. Air temperatures should rise above freezing
across the board by 15z/10am, so any icing would melt quickly.
However, any ice on initially dry roads can be very slippery.
Will follow the HRRR depiction of rain advancing eastward in a band
that matches the current radar trends rather closely. Likely and
categorical PoPs this morning will be confined to the western
counties where low level saturation will occur the soonest.
The band of warm F-gen will gradually shift north this afternoon,
giving the precip a northward push as well. Have kept likely PoPs
across the northern half of our area through the afternoon.
Instability params support elevated thunderstorms today, generally
in the southwest half of our forecast area.
High temps today will be held in check by the cool east-northeast
flow that will persist through the day. Most areas will see the
mid-upper 40s this afternoon.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 329 AM CDT TUE MAR 24 2015
Deepening surface low pressure currently at 1006 mb over the OK
panhandle to eject ne into the IL river valley over central IL by
06Z/1 am tonight and then to southern part of Lake MI by 12Z/7 am
Wed and swing a cold front through central and eastern IL overnight.
Showers likely ahead of this front along with chances of
thunderstorms. SPC has marginal risk over much of central IL
(excluding Knox, Stark and Marshall counties) with slight risk of
severe storms this evening across central and sw MO from St Louis
southwest. Lows tonight range from upper 30s to near 40F over IL
river valley to upper 40s and lower 50s in southeast IL.
Central IL to be in between weather systems during the day Wed as low
pressure passes ne of the Great Lakes and another surface low
pressure organizes over the southern plains. Isolated showers and
thunderstorms to be possible later Wed afternoon south of I-72.
Milder highs Wed mostly in the 60s, ranging from around 60F from
Peoria north to upper 60s and lower 70s in southeast IL. 1007 mb low
pressure to track ne into far southern IL by 06Z/1 AM Wed night and
up the Ohio river to near the OH/KY border by dawn Thu. Models have
trended further south with this low pressure track, and SPC has
shifted slight risk of severe storms Wed night south of our CWA with
marginal risk into southeast counties along and south of I-70. Heavy
rains of 1-1.5 inches possible south of I-70 Wed night while rain
chances taper off to 20-30% nw of the IL river. Lows Wed night range
from mid 30s over IL river valley to 40-45F in southeast IL from I-70
southeast.
Lingered a chance of rain showers in southeast IL Thu morning then
low pressure moves into south-central PA by midday Thu and far enough
way to end rain chances Thu afternoon. Much cooler highs Thu in the
mid to upper 40s central IL and near 50F southeast IL. Even colder
Friday with highs in the upper 30s and lower 40s, coolest from I-74
ne. Models have been consistent in digging strong upper level trof
into the eastern states Thu/Fri bringing in the very cool
temperatures. 1030 mb Canadian high pressure settles into the Great
Lakes region Fri night and Sat with clouds and winds decreasing and
continued cold temps. Lows Fri night in the low to mid 20s. Highs
Sat in the low to mid 40s.
A cutoff upper level low passes north of the Great Lakes Sunday
keeping best chances of precipitation north of central IL, though
did carry small chances of light rain showers Sunday. Milder highs
Sunday and Monday in the mid to upper 50s with west central IL
around 60F.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 100 PM CDT TUE MAR 24 2015
Quasi stationary boundary at the surface just south of Central
Illinois terminals slow to move this afternoon, delaying the onset
of the MVFR/IFR stratus deck in PIA BMI and CMI. SPI BKN012
now...DEC soon to follow suit. Showers moving along SPI to DEC
path as well, with more rain to the west. Afternoon showers and
thunderstorms late remaining possible, though coverage anticipated
to be rather sparse...keeping the mention to VC since the warm
sector of the approaching low is delayed until after sunset.
Tightening pressure gradient however, will result in some rather
gusty winds after sunset/before midnight gusting to 30kts...mainly
out of the SE. IFR through the overnight hours. Clearing in the
morning with the llvl moisture trapped/enhanced may be delayed
considerably and since the operational models are not clearing
until closer to 16-18z...am holding off mention of improvement
just yet.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Shimon
LONG TERM...07
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1104 AM CDT TUE MAR 24 2015
.SHORT TERM...
249 AM CDT
THROUGH TONIGHT...
IR IMAGERY EARLY THIS MORNING INDICATED THE STRATUS LAYER HAS
PUSHED WEST OF THE CHICAGO AREA...HOWEVER A FEW POCKETS OF STRATUS
HAVE BEEN REDEVELOPING AND SLIDING ACROSS FAR NORTHEAST IL. TEMPS
ARE GENERALLY REMAINED IN THE UPR 20S EARLY THIS MORNING...WITH A
FEW LOCATIONS RADIATING INTO THE LOW 20S. A NARROW CHANNEL OF
CIRRUS WAS ALREADY STREAMING NORTHEAST FROM THE DEVELOPING
SHORTWAVE CURRENTLY CENTERED OVER THE CENTRAL PLAINS. THE GRADIENT
WILL REMAIN LIGHT THROUGH DAYBREAK...HOWEVER THE WEAK DIFFLUENT
FLOW WILL QUICKLY DISSIPATE AND MIXING WILL STEADILY INCREASE BY
MID-MORNING. GUIDANCE INDICATES SPEEDS THROUGH THE CHANNEL ARND
20KT.
THE MOIST AXIS DOES APPEAR TO BE SLIGHTLY SLOWER TO ARRIVE ACROSS
NORTHEAST IL UNTIL AFT 21Z...SO HAVE NUDGED TIMING BACK AN HOUR OR
TWO. COULD SEE PRECIP PUSHING INTO THE FAR SOUTHWEST CWFA ARND 18-
20Z...HOWEVER WITH THE WEAK DIFFLUENT FLOW LINGERING FURTHER
NORTH...THIS MAY HELP TO HOLD-OFF PRECIP UNTIL CLOSER TO 00Z. WITH A
STEADY CONVEYOR OF SLIGHTLY WARMER AIR ADVECTING NORTH THIS
AFTN...TEMPS ARE EXPECTED TO WARM TO ARND 40. THE CONCERN IS THAT
WITH THE FRESH SNOWPACK THIS MAY HOLD TEMPS DOWN A DEGREE OR TWO.
TONIGHT...
AS ELUDED TOO ABOVE...PRECIP WILL BE STEADILY INCREASING IN
COVERAGE THIS EVENING. BUT THE MAIN CONCERN FOR TONIGHT WILL
REVOLVE AROUND CONVECTION AND POSSIBLY SOME STRONGER EMBEDDED
THUNDERSTORMS. MID- LVL SHEAR IS IMPRESSIVE THIS EVENING...WITH
VALUES NEARING 40-50KTS. GIVEN THE RATHER MOIST PROFILE AND CLOUDY
ENVIRONMENT...CAPE VALUES WILL REMAIN MINIMAL. 0-3KM BULK SHEAR IS
EQUALLY IMPRESSIVE WITH THIS DYNAMIC NEGATIVELY TILTED SHORTWAVE
TONIGHT. THE SPC HAS THE AREAS SOUTH OF PONTIAC TO FOWLER IN A
MARGINAL RISK FOR SEVERE STORMS TONIGHT.
DEW POINTS WILL BE STEADILY INCREASING THIS EVENING AS WELL...AS
WARM AIR CONTINUES TO ADVECT NORTH. BY LATE THIS EVENING DEW POINTS
WILL BE APPROACHING THE LOW/MID 30S...AND POSSIBLY NEAR 40 ACROSS
THE FAR SOUTH. THEN OVERNIGHT DEW POINTS WILL CONTINUE TO RISE INTO
THE MID/UPR 30S NORTH...AND LOW 40S SOUTH. THIS SHOULD AID IN EATING
INTO THE SNOWPACK RATHER QUICKLY...COUPLED WITH THE RAIN AS WELL.
PWAT VALUES WILL BE NEARING 1 INCH LATE TONIGHT...AS THE MOISTURE
TRANSPORT CONTINUES TO FEED NORTH ACROSS THE FORECAST AREA. CURRENT
TRACK OF THE SHORTWAVE IS TO LIFT NORTHEAST ACROSS PONTIAC TO GARY
BY 9Z...WHICH SHUD HELP PUSH CONVECTIVE COVERAGE EAST/NORTHEAST BY
DAYBREAK WED.
BEACHLER
&&
.LONG TERM...
350 AM CDT
WEDNESDAY NIGHT THROUGH MONDAY...
THE MAIN STORY DURING THE LONGER TERM PERIOD WILL BE THE AMPLIFYING
UPPER LEVEL FLOW PATTERN ACROSS NORTH AMERICA. UPPER LEVEL RIDGING
IS FORECAST TO BUILD OVER THE WESTERN CONUS IN RESPONSE TO THE
PROGRESSION A SIGNIFICANT DISTURBANCE OVER THE NORTHERN
PACIFIC...AND THIS WILL ULTIMATELY DRIVE SIGNIFICANT HEIGHT FALLS
AND TROUGHING OVER THE THE EASTERN HALF OF THE CONUS. AS A
RESULT...EXPECT TO TRANSITION BACK TO A PERIOD OF MUCH BELOW AVERAGE
TEMPERATURES LATE THIS WEEK INTO THE FIRST HALF OF THE WEEKEND.
THE PERIOD WILL START OUT MILD ON WEDNESDAY FOLLOWING THE PASSAGE OF
THE TUESDAY NIGHT STORM SYSTEM. IT DOES APPEAR THAT CLOUD COVER
COULD LINGER DURING THE DAY ON WEDNESDAY...AND THIS COULD LIMIT THE
AMOUNT OF WARMING WE EXPERIENCE DURING THE DAY. HOWEVER...WITH THE
COLDER AIRMASS NOT ARRIVING ACROSS THE AREA UNTIL LATER WEDNESDAY
NIGHT TEMPERATURES SHOULD BE ABLE TO CLIMB TO...AT LEAST...NEAR 50
DEGREES. AREAS SOUTH OF INTERSTATE 80 STAND THE BEST CHANCES TO
CLIMB WELL INTO THE 50S.
AS A COLD FRONT BEGINS TO SHIFT ACROSS NORTHERN ILLINOIS WEDNESDAY
NIGHT A WEAK SURFACE WAVE OF LOW PRESSURE IS EXPECTED TO DEVELOP
OVER THE SOUTHERN PLAINS...BEFORE QUICKLY SHIFTING NORTHEASTWARD
ALONG THE FRONT INTO THURSDAY MORNING. INCREASING FGEN ALONG THIS
FRONTAL WAVE SHOULD RESULT IN PRECIPITATION DEVELOPMENT WEDNESDAY
NIGHT...PRIMARILY ACROSS MY EAST CENTRAL ILLINOIS AND NORTHWESTERN
INDIANA COUNTIES. THIS ACTIVITY WILL SHIFT TO THE SOUTH AND EAST OF
MY AREA BY EARLY THURSDAY MORNING AS THE COLD FRONT CONTINUES TO
SHIFT SOUTHEASTWARD. DRY BUT COOLER WEATHER IN THE LOW TO 40S IS
EXPECTED FOR THE DAY THURSDAY.
ANOTHER STRONGER PUSH OF COLD AIR WILL ARRIVE OVER THE AREA BY
THURSDAY NIGHT INTO FRIDAY AS YET ANOTHER COLD FRONT SHIFTS OVER THE
AREA. STEEPENING LOW LEVEL LAPSE RATES OVER LAKE MICHIGAN WITH THIS
COLD AIR MASS COULD EVEN RESULT IN SOME LAKE EFFECT SNOW SHOWERS
ACROSS NORTHEASTERN ILLINOIS AND NORTHWESTERN INDIANA INTO FRIDAY
MORNING...AND THIS ACTIVITY LOOKS AS THOUGH IT COULD BE COMPLIMENTED
BY ANOTHER UPPER LEVEL PV ANOMALY DIGGING INTO THE BASE OF THE UPPER
LEVEL TROUGH OVER THE AREA. IF THIS SCENARIO PANS OUT AS CURRENTLY
FORECAST...THERE COULD BE SOME MINOR SNOW ACCUMULATIONS ACROSS
PORTIONS OF THE AREA WITH THIS ACTIVITY INTO FRIDAY.
WITH THE HEART OF THE COLD AIR MASS EXPECTED TO BE OVERHEAD ON
FRIDAY...IT LOOKS TO BE THE COLDEST DAY. HIGH TEMPERATURES ARE
CURRENTLY ONLY FORECAST TO GET INTO THE LOWER TO MID 30S...WHICH IS
A GOOD 15 TO 20 DEGREES BELOW AVERAGE. SURFACE HIGH PRESSURE SHOULD
BECOME CENTERED OVER OR NEAR THE AREA BY LATE FRIDAY NIGHT...SO THIS
SHOULD ALLOW TEMPERATURES FRIDAY NIGHT TO DROP INTO THE TEENS
INTO SATURDAY MORNING OUTSIDE OF CHICAGO.
AFTER ANOTHER WELL BELOW AVERAGE DAY ON SATURDAY...THINGS LOOKS TO
WARM BACK UP BY SUNDAY SURFACE RIDGE SHIFTS OVER THE SOUTHEASTERN
CONUS. IT APPEARS THAT SUNDAY COULD END UP NOT ONLY BEING A WARMER
DAY...WITH HIGHS POTENTIALLY WARMING BACK UP NEAR OR JUST ABOVE
AVERAGE...BUT ALSO A VERY BREEZY DAY. FORECAST GUIDANCE SUGGESTS
THAT A POTENT CLIPPER SYSTEM WILL TRACK EAST-SOUTHEASTWARD OVER
SOUTHERN ONTARIO...WHICH COULD SET UP A SURFACE GRADIENT SUPPORTIVE
OF SOME STRONG SOUTHWESTERLY WINDS. IN ADDITION...THE INCREASING WARM
AIR ADVECTON REGIME OVER THE AREA COULD ALSO RESULT IN THE
DEVELOPMENT OF SOME LIGHT RAIN SHOWERS DURING THE DAY.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* EAST WINDS AT 10-15 KT WITH GUSTS UP TO 20 KT LATE THIS AFTN
THRU THIS EVE.
* SHOWERS ARRIVE AROUND 00Z WITH STEADY RAINFALL AND MVFR VSBY
ARRIVING LATE THIS EVENING.
* IFR OR LOWER CIGS EXPECTED WITH STEADY RAIN THIS EVENING AND
OVERNIGHT.
* LLWS THIS EVE.
* GUSTY SOUTHWEST TO WEST WINDS TOMORROW.
JEE
//DISCUSSION...UPDATED 12Z...
STRATUS CLOUDS HAVE PUSHED WELL TO THE WEST/SOUTHWEST OF THE TAF
SITES EARLY THIS MORNING. IR IMAGERY INDICATES A LAYER OF MID/HIGH
DECK CLOUDS BEGINNING TO STREAM NORTHEAST ACROSS NORTHERN
IL/NORTHWEST IN THIS MORNING. AS THE LOW PRESSURE OVER THE CENTRAL
PLAINS NUDGES NORTHEAST TOWARDS NORTHERN IL AIRFIELDS...WINDS WILL
BEGIN TO INCREASE AND TURN SOUTHEASTERLY LATER THIS MORNING. GUSTS
SHUD START TO INCREASE IN FREQUENCY ARND 20Z...THEN CONTINUE TO
INCREASE IN SPEEDS BY THIS AFTN NEARING 20-23KT. RAIN IS EXPECTED
TO DEVELOP LATE THIS AFTN AND ARRIVE ACROSS THE TAF SITES LATE
AFTN/EARLY EVE...WITH COVERAGE INCREASING LATER TONIGHT. EXPECT
THE MOIST ATMOSPHERE TO ALLOW CIGS TO DROP TO IFR/LOW-END MVFR
LATER TONIGHT THROUGH THE OVERNIGHT HOURS.
IN ADDITION TO THE RAIN WILL BE THE POTENTIAL FOR EMBEDDED
THUNDERSTORMS...HOWEVER THE BEST CHANCE FOR THUNDER APPEARS TO BE
SOUTH OF THE TAF SITES. SO HAVE OPTED TO HOLD OFF ON INCLUDING
THUNDER WITHIN THE CURRENT TAF. LATER TONIGHT THE WINDS AT 2KFT
AGL ARE FORECAST TO APPROACH 50KT AS A LOW LEVEL JET ARRIVES.
EXPECT THE SFC TO BE DECOUPLED FROM THE WINDS ALOFT...SO WILL
CARRY LLWS WITHIN THE TAF. AS THE LOW LIFTS OVERHEAD EARLY WED
MORNING WINDS WILL DIMINISH...THEN INCREASE ARND DAYBREAK ALONG
WITH VEERING WEST. AS THE LOW PASSES OVERHEAD PRECIP WILL COME TO
AN END...HOWEVER MVFR TO IFR CIGS ARE EXPECTED TO PERSIST UNTIL
LATE WED MORNING.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN RAIN...MEDIUM-HIGH CONFIDENCE IN TIMING.
* MEDIUM-LOW CONFIDENCE IN OCCURRENCE AND COVERAGE OF TS.
* HIGH CONFIDENCE IN LOWER CIGS...MEDIUM CONFIDENCE IN TIMING AND
HOW LOW THEY WILL BE.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...WEST TO NORTHWEST WINDS. MAINLY VFR CONDS.
THURSDAY...CHANCE OF SNOW SHOWERS MAINLY IN THE EVENING. MVFR
POSSIBLE.
FRIDAY...SLIGHT CHANCE OF LIGHT SNOW EARLY. OTHERWISE PRIMARILY
VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF RAIN. PATCHY MVFR POSSIBLE.
MONDAY...VFR.
BEACHLER
&&
.MARINE...
409 AM CDT
WINDS WILL BEGIN TO INCREASE OUT OF THE SOUTHEAST OVER SOUTHERN LAKE
MICHIGAN THIS EVENING AS AN AREA OF LOW PRESSURE MOVES TOWARDS
NORTHERN ILLINOIS. IT NOW APPEARS THAT THE SURFACE LOW WILL TAKE A
TRACK RIGHT ACROSS SOUTHERN LAKE MICHIGAN LATE TONIGHT INTO EARLY
WEDNESDAY MORNING. THEREFORE...AS THE LOW MOVES OVER THE
LAKE...WINDS WILL LIKELY BECOME LIGHT AND VARIABLE FOR SHORT
PERIOD OVER FAR SOUTHERN LAKE MICHIGAN. WEST SOUTHWESTERLY WINDS
WILL ENSURE AS THE LOW SHIFTS OVER LOWER MICHIGAN WEDNESDAY
MORNING. WIND SPEEDS COULD APPROACH 25 TO 30 KT DURING THE
MORNING...BUT WIND SPEEDS SHOULD BE ON A DIMINISHING TREND THROUGH
THE DAY.
A COLD FRONT WILL SHIFT DOWN THE LAKE WEDNESDAY NIGHT...RESULTING IN
A NORTHERLY WIND SHIFT FOR THURSDAY. WINDS SPEEDS SHOULD ALSO
INCREASE UP TO 25 TO 30 KT BY THURSDAY EVENING AS THE SURFACE
GRADIENT TIGHTENS AHEAD OF AN AREA OF HIGH PRESSURE SHIFTING
SOUTHEASTWARD OVER THE UPPER MIDWEST. THIS SURFACE HIGH IS EXPECTED
TO SHIFT SOUTHEASTWARD OVER NORTHEASTERN ILLINOIS SATURDAY
MORNING...THEN SHIFT OVER THE SOUTHEASTERN CONUS BY SUNDAY. IT
APPEARS THAT ANOTHER SIGNIFICANT SOUTHERLY WIND EVENT COULD SET UP
FOR SUNDAY AS A POTENTIAL STORM SYSTEM TRACKS ACROSS SOUTHERN
ONTARIO.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...7 PM TUESDAY TO 4 PM WEDNESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1103 AM CDT Tue Mar 24 2015
.UPDATE...
ISSUED AT 1038 AM CDT TUE MAR 24 2015
High pressure sliding east as another low develops over the Plains
and moves into the Midwest later this evening. For now, a frontal
boundary not making much progress northward up into the region.
Between the slower approach of the front and the persistent cloud
cover, have pulled down todays highs. Would like to bring them
down further, but sat imagery starting to show some holes here and
there...and any clearing in the afternoon hours may allow for some
warming...but the highs for today will definitely wait until the
end of the day...with temps steady or climbing through the
overnight hours.
&&
.SHORT TERM...(Today)
ISSUED AT 329 AM CDT TUE MAR 24 2015
A band of mid-level warm frontogenesis will advance into central IL
from the west this morning, causing rain showers to eventually
develop through the dry low level airmass. The leading edge of the
rain band will likely encounter areas with surface temps at or just
below freezing, but not sure how far south will freezing rain
affect. 08z obs show only Jacksonville and Lawrenceville above
freezing, while the remainder of our C and SE IL obs at or below
freezing. Will need to include a mention of freezing rain a bit
farther south this morning as a result. Road surface temps on IDOT
sites showing road temps ranging from 34 to as low as 31F. We could
see some slippery road conditions develop with this initial rain
falling on dry pavement. Air temperatures should rise above freezing
across the board by 15z/10am, so any icing would melt quickly.
However, any ice on initially dry roads can be very slippery.
Will follow the HRRR depiction of rain advancing eastward in a band
that matches the current radar trends rather closely. Likely and
categorical PoPs this morning will be confined to the western
counties where low level saturation will occur the soonest.
The band of warm F-gen will gradually shift north this afternoon,
giving the precip a northward push as well. Have kept likely PoPs
across the northern half of our area through the afternoon.
Instability params support elevated thunderstorms today, generally
in the southwest half of our forecast area.
High temps today will be held in check by the cool east-northeast
flow that will persist through the day. Most areas will see the
mid-upper 40s this afternoon.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 329 AM CDT TUE MAR 24 2015
Deepening surface low pressure currently at 1006 mb over the OK
panhandle to eject ne into the IL river valley over central IL by
06Z/1 am tonight and then to southern part of Lake MI by 12Z/7 am
Wed and swing a cold front through central and eastern IL overnight.
Showers likely ahead of this front along with chances of
thunderstorms. SPC has marginal risk over much of central IL
(excluding Knox, Stark and Marshall counties) with slight risk of
severe storms this evening across central and sw MO from St Louis
southwest. Lows tonight range from upper 30s to near 40F over IL
river valley to upper 40s and lower 50s in southeast IL.
Central IL to be in between weather systems during the day Wed as low
pressure passes ne of the Great Lakes and another surface low
pressure organizes over the southern plains. Isolated showers and
thunderstorms to be possible later Wed afternoon south of I-72.
Milder highs Wed mostly in the 60s, ranging from around 60F from
Peoria north to upper 60s and lower 70s in southeast IL. 1007 mb low
pressure to track ne into far southern IL by 06Z/1 AM Wed night and
up the Ohio river to near the OH/KY border by dawn Thu. Models have
trended further south with this low pressure track, and SPC has
shifted slight risk of severe storms Wed night south of our CWA with
marginal risk into southeast counties along and south of I-70. Heavy
rains of 1-1.5 inches possible south of I-70 Wed night while rain
chances taper off to 20-30% nw of the IL river. Lows Wed night range
from mid 30s over IL river valley to 40-45F in southeast IL from I-70
southeast.
Lingered a chance of rain showers in southeast IL Thu morning then
low pressure moves into south-central PA by midday Thu and far enough
way to end rain chances Thu afternoon. Much cooler highs Thu in the
mid to upper 40s central IL and near 50F southeast IL. Even colder
Friday with highs in the upper 30s and lower 40s, coolest from I-74
ne. Models have been consistent in digging strong upper level trof
into the eastern states Thu/Fri bringing in the very cool
temperatures. 1030 mb Canadian high pressure settles into the Great
Lakes region Fri night and Sat with clouds and winds decreasing and
continued cold temps. Lows Fri night in the low to mid 20s. Highs
Sat in the low to mid 40s.
A cutoff upper level low passes north of the Great Lakes Sunday
keeping best chances of precipitation north of central IL, though
did carry small chances of light rain showers Sunday. Milder highs
Sunday and Monday in the mid to upper 50s with west central IL
around 60F.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 638 AM CDT TUE MAR 24 2015
Initial concern will be light freezing rain at SPI and DEC through
14z. Surface temperatures will be right around the freezing mark
through this time frame so some light icing is not out of the
question before temperatures edge into the middle 30s by mid to
late morning. Further north and east, the latest short term models
suggest the precip may struggle to shift north before 15z so will
hold back the precip threat up at PIA and BMI until after 15z. By
then, it appears the precip would be mostly rain with the
possibility for some isolated convection over parts of west
central and central IL during the morning. For now, will hold off
mentioning any -tsra during the morning, with the better threat for
isolated thunderstorms coming along this evening, as low pressure
passes across IL. MVFR and local IFR cigs will prevail thru most
of this forecast period with periods of rain through this
evening. Rain should come to an end from SW to NE as the low pulls
away into Indiana after midnight.
Surface winds will remain out of the east today, with a gradual
turn into the southeast and then south this evening as the surface
low approaches our area. Wind speeds will range from 12 to 17 kts
with gusts around 22 kts at times this afternoon and early this
evening.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
650 AM CDT TUE MAR 24 2015
.SHORT TERM...
249 AM CDT
THROUGH TONIGHT...
IR IMAGERY EARLY THIS MORNING INDICATED THE STRATUS LAYER HAS
PUSHED WEST OF THE CHICAGO AREA...HOWEVER A FEW POCKETS OF STRATUS
HAVE BEEN REDEVELOPING AND SLIDING ACROSS FAR NORTHEAST IL. TEMPS
ARE GENERALLY REMAINED IN THE UPR 20S EARLY THIS MORNING...WITH A
FEW LOCATIONS RADIATING INTO THE LOW 20S. A NARROW CHANNEL OF
CIRRUS WAS ALREADY STREAMING NORTHEAST FROM THE DEVELOPING
SHORTWAVE CURRENTLY CENTERED OVER THE CENTRAL PLAINS. THE GRADIENT
WILL REMAIN LIGHT THROUGH DAYBREAK...HOWEVER THE WEAK DIFFLUENT
FLOW WILL QUICKLY DISSIPATE AND MIXING WILL STEADILY INCREASE BY
MID-MORNING. GUIDANCE INDICATES SPEEDS THROUGH THE CHANNEL ARND
20KT.
THE MOIST AXIS DOES APPEAR TO BE SLIGHTLY SLOWER TO ARRIVE ACROSS
NORTHEAST IL UNTIL AFT 21Z...SO HAVE NUDGED TIMING BACK AN HOUR OR
TWO. COULD SEE PRECIP PUSHING INTO THE FAR SOUTHWEST CWFA ARND 18-
20Z...HOWEVER WITH THE WEAK DIFFLUENT FLOW LINGERING FURTHER
NORTH...THIS MAY HELP TO HOLD-OFF PRECIP UNTIL CLOSER TO 00Z. WITH A
STEADY CONVEYOR OF SLIGHTLY WARMER AIR ADVECTING NORTH THIS
AFTN...TEMPS ARE EXPECTED TO WARM TO ARND 40. THE CONCERN IS THAT
WITH THE FRESH SNOWPACK THIS MAY HOLD TEMPS DOWN A DEGREE OR TWO.
TONIGHT...
AS ELUDED TOO ABOVE...PRECIP WILL BE STEADILY INCREASING IN
COVERAGE THIS EVENING. BUT THE MAIN CONCERN FOR TONIGHT WILL
REVOLVE AROUND CONVECTION AND POSSIBLY SOME STRONGER EMBEDDED
THUNDERSTORMS. MID- LVL SHEAR IS IMPRESSIVE THIS EVENING...WITH
VALUES NEARING 40-50KTS. GIVEN THE RATHER MOIST PROFILE AND CLOUDY
ENVIRONMENT...CAPE VALUES WILL REMAIN MINIMAL. 0-3KM BULK SHEAR IS
EQUALLY IMPRESSIVE WITH THIS DYNAMIC NEGATIVELY TILTED SHORTWAVE
TONIGHT. THE SPC HAS THE AREAS SOUTH OF PONTIAC TO FOWLER IN A
MARGINAL RISK FOR SEVERE STORMS TONIGHT.
DEW POINTS WILL BE STEADILY INCREASING THIS EVENING AS WELL...AS
WARM AIR CONTINUES TO ADVECT NORTH. BY LATE THIS EVENING DEW POINTS
WILL BE APPROACHING THE LOW/MID 30S...AND POSSIBLY NEAR 40 ACROSS
THE FAR SOUTH. THEN OVERNIGHT DEW POINTS WILL CONTINUE TO RISE INTO
THE MID/UPR 30S NORTH...AND LOW 40S SOUTH. THIS SHOULD AID IN EATING
INTO THE SNOWPACK RATHER QUICKLY...COUPLED WITH THE RAIN AS WELL.
PWAT VALUES WILL BE NEARING 1 INCH LATE TONIGHT...AS THE MOISTURE
TRANSPORT CONTINUES TO FEED NORTH ACROSS THE FORECAST AREA. CURRENT
TRACK OF THE SHORTWAVE IS TO LIFT NORTHEAST ACROSS PONTIAC TO GARY
BY 9Z...WHICH SHUD HELP PUSH CONVECTIVE COVERAGE EAST/NORTHEAST BY
DAYBREAK WED.
BEACHLER
&&
.LONG TERM...
350 AM CDT
WEDNESDAY NIGHT THROUGH MONDAY...
THE MAIN STORY DURING THE LONGER TERM PERIOD WILL BE THE AMPLIFYING
UPPER LEVEL FLOW PATTERN ACROSS NORTH AMERICA. UPPER LEVEL RIDGING
IS FORECAST TO BUILD OVER THE WESTERN CONUS IN RESPONSE TO THE
PROGRESSION A SIGNIFICANT DISTURBANCE OVER THE NORTHERN
PACIFIC...AND THIS WILL ULTIMATELY DRIVE SIGNIFICANT HEIGHT FALLS
AND TROUGHING OVER THE THE EASTERN HALF OF THE CONUS. AS A
RESULT...EXPECT TO TRANSITION BACK TO A PERIOD OF MUCH BELOW AVERAGE
TEMPERATURES LATE THIS WEEK INTO THE FIRST HALF OF THE WEEKEND.
THE PERIOD WILL START OUT MILD ON WEDNESDAY FOLLOWING THE PASSAGE OF
THE TUESDAY NIGHT STORM SYSTEM. IT DOES APPEAR THAT CLOUD COVER
COULD LINGER DURING THE DAY ON WEDNESDAY...AND THIS COULD LIMIT THE
AMOUNT OF WARMING WE EXPERIENCE DURING THE DAY. HOWEVER...WITH THE
COLDER AIRMASS NOT ARRIVING ACROSS THE AREA UNTIL LATER WEDNESDAY
NIGHT TEMPERATURES SHOULD BE ABLE TO CLIMB TO...AT LEAST...NEAR 50
DEGREES. AREAS SOUTH OF INTERSTATE 80 STAND THE BEST CHANCES TO
CLIMB WELL INTO THE 50S.
AS A COLD FRONT BEGINS TO SHIFT ACROSS NORTHERN ILLINOIS WEDNESDAY
NIGHT A WEAK SURFACE WAVE OF LOW PRESSURE IS EXPECTED TO DEVELOP
OVER THE SOUTHERN PLAINS...BEFORE QUICKLY SHIFTING NORTHEASTWARD
ALONG THE FRONT INTO THURSDAY MORNING. INCREASING FGEN ALONG THIS
FRONTAL WAVE SHOULD RESULT IN PRECIPITATION DEVELOPMENT WEDNESDAY
NIGHT...PRIMARILY ACROSS MY EAST CENTRAL ILLINOIS AND NORTHWESTERN
INDIANA COUNTIES. THIS ACTIVITY WILL SHIFT TO THE SOUTH AND EAST OF
MY AREA BY EARLY THURSDAY MORNING AS THE COLD FRONT CONTINUES TO
SHIFT SOUTHEASTWARD. DRY BUT COOLER WEATHER IN THE LOW TO 40S IS
EXPECTED FOR THE DAY THURSDAY.
ANOTHER STRONGER PUSH OF COLD AIR WILL ARRIVE OVER THE AREA BY
THURSDAY NIGHT INTO FRIDAY AS YET ANOTHER COLD FRONT SHIFTS OVER THE
AREA. STEEPENING LOW LEVEL LAPSE RATES OVER LAKE MICHIGAN WITH THIS
COLD AIR MASS COULD EVEN RESULT IN SOME LAKE EFFECT SNOW SHOWERS
ACROSS NORTHEASTERN ILLINOIS AND NORTHWESTERN INDIANA INTO FRIDAY
MORNING...AND THIS ACTIVITY LOOKS AS THOUGH IT COULD BE COMPLIMENTED
BY ANOTHER UPPER LEVEL PV ANOMALY DIGGING INTO THE BASE OF THE UPPER
LEVEL TROUGH OVER THE AREA. IF THIS SCENARIO PANS OUT AS CURRENTLY
FORECAST...THERE COULD BE SOME MINOR SNOW ACCUMULATIONS ACROSS
PORTIONS OF THE AREA WITH THIS ACTIVITY INTO FRIDAY.
WITH THE HEART OF THE COLD AIR MASS EXPECTED TO BE OVERHEAD ON
FRIDAY...IT LOOKS TO BE THE COLDEST DAY. HIGH TEMPERATURES ARE
CURRENTLY ONLY FORECAST TO GET INTO THE LOWER TO MID 30S...WHICH IS
A GOOD 15 TO 20 DEGREES BELOW AVERAGE. SURFACE HIGH PRESSURE SHOULD
BECOME CENTERED OVER OR NEAR THE AREA BY LATE FRIDAY NIGHT...SO THIS
SHOULD ALLOW TEMPERATURES FRIDAY NIGHT TO DROP INTO THE TEENS
INTO SATURDAY MORNING OUTSIDE OF CHICAGO.
AFTER ANOTHER WELL BELOW AVERAGE DAY ON SATURDAY...THINGS LOOKS TO
WARM BACK UP BY SUNDAY SURFACE RIDGE SHIFTS OVER THE SOUTHEASTERN
CONUS. IT APPEARS THAT SUNDAY COULD END UP NOT ONLY BEING A WARMER
DAY...WITH HIGHS POTENTIALLY WARMING BACK UP NEAR OR JUST ABOVE
AVERAGE...BUT ALSO A VERY BREEZY DAY. FORECAST GUIDANCE SUGGESTS
THAT A POTENT CLIPPER SYSTEM WILL TRACK EAST-SOUTHEASTWARD OVER
SOUTHERN ONTARIO...WHICH COULD SET UP A SURFACE GRADIENT SUPPORTIVE
OF SOME STRONG SOUTHWESTERLY WINDS. IN ADDITION...THE INCREASING WARM
AIR ADVECTON REGIME OVER THE AREA COULD ALSO RESULT IN THE
DEVELOPMENT OF SOME LIGHT RAIN SHOWERS DURING THE DAY.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* EAST WINDS PERSIST BETWEEN 5-8KT...INCREASING LATE MORNING TO
10-12KT. WINDS TURN SOUTHEAST AND INCREASE MID-MORNING...SPEEDS
BETWEEN 12-15KT WITH GUSTS UP TO 20KT.
* RAIN DEVELOPS LATE AFTN/EARLY EVE...WITH STEADIER RAIN AFT 00Z
WED. EMBEDDED THUNDER POSSIBLE AFT 00Z WED. IFR CIGS DEVELOP.
* LLWS POSSIBLE LATE TONIGHT...AOA 2KFT AGL SPEEDS INCREASE TO
50KT FROM SOUTHEAST AFT 2Z WED.
* LULL IN WINDS PRIOR TO DAYBREAK WED...THEN VEERING WEST AND
INCREASING JUST AFTER DAYBREAK WED.
BEACHLER
//DISCUSSION...UPDATED 12Z...
STRATUS CLOUDS HAVE PUSHED WELL TO THE WEST/SOUTHWEST OF THE TAF
SITES EARLY THIS MORNING. IR IMAGERY INDICATES A LAYER OF MID/HIGH
DECK CLOUDS BEGINNING TO STREAM NORTHEAST ACROSS NORTHERN
IL/NORTHWEST IN THIS MORNING. AS THE LOW PRESSURE OVER THE CENTRAL
PLAINS NUDGES NORTHEAST TOWARDS NORTHERN IL AIRFIELDS...WINDS WILL
BEGIN TO INCREASE AND TURN SOUTHEASTERLY LATER THIS MORNING. GUSTS
SHUD START TO INCREASE IN FREQUENCY ARND 20Z...THEN CONTINUE TO
INCREASE IN SPEEDS BY THIS AFTN NEARING 20-23KT. RAIN IS EXPECTED
TO DEVELOP LATE THIS AFTN AND ARRIVE ACROSS THE TAF SITES LATE
AFTN/EARLY EVE...WITH COVERAGE INCREASING LATER TONIGHT. EXPECT
THE MOIST ATMOSPHERE TO ALLOW CIGS TO DROP TO IFR/LOW-END MVFR
LATER TONIGHT THROUGH THE OVERNIGHT HOURS.
IN ADDITION TO THE RAIN WILL BE THE POTENTIAL FOR EMBEDDED
THUNDERSTORMS...HOWEVER THE BEST CHANCE FOR THUNDER APPEARS TO BE
SOUTH OF THE TAF SITES. SO HAVE OPTED TO HOLD OFF ON INCLUDING
THUNDER WITHIN THE CURRENT TAF. LATER TONIGHT THE WINDS AT 2KFT
AGL ARE FORECAST TO APPROACH 50KT AS A LOW LEVEL JET ARRIVES.
EXPECT THE SFC TO BE DECOUPLED FROM THE WINDS ALOFT...SO WILL
CARRY LLWS WITHIN THE TAF. AS THE LOW LIFTS OVERHEAD EARLY WED
MORNING WINDS WILL DIMINISH...THEN INCREASE ARND DAYBREAK ALONG
WITH VEERING WEST. AS THE LOW PASSES OVERHEAD PRECIP WILL COME TO
AN END...HOWEVER MVFR TO IFR CIGS ARE EXPECTED TO PERSIST UNTIL
LATE WED MORNING.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE IN CIGS THRU 20Z...MEDIUM CONFIDENCE IN TIMING
OF MVFR/IFR CIGS AFT 00Z WED.
* HIGH CONFIDENCE IN RAIN DEVELOPING AFT 22Z...LOW CONFIDENCE IN
PRECISE TIMING. MEDIUM/LOW IN THUNDER TIMING AND COVERAGE
OVERNIGHT INTO EARLY WED MORNING.
* HIGH CONFIDECE IN LLWS DEVELOPING AND MEDIUM CONFIDENCE IN
SPEEDS OF LLWS.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT...WEST TO NORTHWEST WINDS. MAINLY VFR CONDS.
THURSDAY...CHANCE OF SNOW SHOWERS MAINLY IN THE EVENING. MVFR
POSSIBLE.
FRIDAY...SLIGHT CHANCE OF LIGHT SNOW EARLY. OTHERWISE PRIMARILY
VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF RAIN. PATCHY MVFR POSSIBLE.
MONDAY...VFR.
BEACHLER
&&
.MARINE...
409 AM CDT
WINDS WILL BEGIN TO INCREASE OUT OF THE SOUTHEAST OVER SOUTHERN LAKE
MICHIGAN THIS EVENING AS AN AREA OF LOW PRESSURE MOVES TOWARDS
NORTHERN ILLINOIS. IT NOW APPEARS THAT THE SURFACE LOW WILL TAKE A
TRACK RIGHT ACROSS SOUTHERN LAKE MICHIGAN LATE TONIGHT INTO EARLY
WEDNESDAY MORNING. THEREFORE...AS THE LOW MOVES OVER THE
LAKE...WINDS WILL LIKELY BECOME LIGHT AND VARIABLE FOR SHORT
PERIOD OVER FAR SOUTHERN LAKE MICHIGAN. WEST SOUTHWESTERLY WINDS
WILL ENSURE AS THE LOW SHIFTS OVER LOWER MICHIGAN WEDNESDAY
MORNING. WIND SPEEDS COULD APPROACH 25 TO 30 KT DURING THE
MORNING...BUT WIND SPEEDS SHOULD BE ON A DIMINISHING TREND THROUGH
THE DAY.
A COLD FRONT WILL SHIFT DOWN THE LAKE WEDNESDAY NIGHT...RESULTING IN
A NORTHERLY WIND SHIFT FOR THURSDAY. WINDS SPEEDS SHOULD ALSO
INCREASE UP TO 25 TO 30 KT BY THURSDAY EVENING AS THE SURFACE
GRADIENT TIGHTENS AHEAD OF AN AREA OF HIGH PRESSURE SHIFTING
SOUTHEASTWARD OVER THE UPPER MIDWEST. THIS SURFACE HIGH IS EXPECTED
TO SHIFT SOUTHEASTWARD OVER NORTHEASTERN ILLINOIS SATURDAY
MORNING...THEN SHIFT OVER THE SOUTHEASTERN CONUS BY SUNDAY. IT
APPEARS THAT ANOTHER SIGNIFICANT SOUTHERLY WIND EVENT COULD SET UP
FOR SUNDAY AS A POTENTIAL STORM SYSTEM TRACKS ACROSS SOUTHERN
ONTARIO.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...7 PM TUESDAY TO 4 PM WEDNESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
638 AM CDT Tue Mar 24 2015
.SHORT TERM...(Today)
ISSUED AT 329 AM CDT TUE MAR 24 2015
A band of mid-level warm frontogenesis will advance into central IL
from the west this morning, causing rain showers to eventually
develop through the dry low level airmass. The leading edge of the
rain band will likely encounter areas with surface temps at or just
below freezing, but not sure how far south will freezing rain
affect. 08z obs show only Jacksonville and Lawrenceville above
freezing, while the remainder of our C and SE IL obs at or below
freezing. Will need to include a mention of freezing rain a bit
farther south this morning as a result. Road surface temps on IDOT
sites showing road temps ranging from 34 to as low as 31F. We could
see some slippery road conditions develop with this initial rain
falling on dry pavement. Air temperatures should rise above freezing
across the board by 15z/10am, so any icing would melt quickly.
However, any ice on initially dry roads can be very slippery.
Will follow the HRRR depiction of rain advancing eastward in a band
that matches the current radar trends rather closely. Likely and
categorical PoPs this morning will be confined to the western
counties where low level saturation will occur the soonest.
The band of warm F-gen will gradually shift north this afternoon,
giving the precip a northward push as well. Have kept likely PoPs
across the northern half of our area through the afternoon.
Instability params support elevated thunderstorms today, generally
in the southwest half of our forecast area.
High temps today will be held in check by the cool east-northeast
flow that will persist through the day. Most areas will see the
mid-upper 40s this afternoon.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 329 AM CDT TUE MAR 24 2015
Deepening surface low pressure currently at 1006 mb over the OK
panhandle to eject ne into the IL river valley over central IL by
06Z/1 am tonight and then to southern part of Lake MI by 12Z/7 am
Wed and swing a cold front through central and eastern IL overnight.
Showers likely ahead of this front along with chances of
thunderstorms. SPC has marginal risk over much of central IL
(excluding Knox, Stark and Marshall counties) with slight risk of
severe storms this evening across central and sw MO from St Louis
southwest. Lows tonight range from upper 30s to near 40F over IL
river valley to upper 40s and lower 50s in southeast IL.
Central IL to be in between weather systems during the day Wed as low
pressure passes ne of the Great Lakes and another surface low
pressure organizes over the southern plains. Isolated showers and
thunderstorms to be possible later Wed afternoon south of I-72.
Milder highs Wed mostly in the 60s, ranging from around 60F from
Peoria north to upper 60s and lower 70s in southeast IL. 1007 mb low
pressure to track ne into far southern IL by 06Z/1 AM Wed night and
up the Ohio river to near the OH/KY border by dawn Thu. Models have
trended further south with this low pressure track, and SPC has
shifted slight risk of severe storms Wed night south of our CWA with
marginal risk into southeast counties along and south of I-70. Heavy
rains of 1-1.5 inches possible south of I-70 Wed night while rain
chances taper off to 20-30% nw of the IL river. Lows Wed night range
from mid 30s over IL river valley to 40-45F in southeast IL from I-70
southeast.
Lingered a chance of rain showers in southeast IL Thu morning then
low pressure moves into south-central PA by midday Thu and far enough
way to end rain chances Thu afternoon. Much cooler highs Thu in the
mid to upper 40s central IL and near 50F southeast IL. Even colder
Friday with highs in the upper 30s and lower 40s, coolest from I-74
ne. Models have been consistent in digging strong upper level trof
into the eastern states Thu/Fri bringing in the very cool
temperatures. 1030 mb Canadian high pressure settles into the Great
Lakes region Fri night and Sat with clouds and winds decreasing and
continued cold temps. Lows Fri night in the low to mid 20s. Highs
Sat in the low to mid 40s.
A cutoff upper level low passes north of the Great Lakes Sunday
keeping best chances of precipitation north of central IL, though
did carry small chances of light rain showers Sunday. Milder highs
Sunday and Monday in the mid to upper 50s with west central IL
around 60F.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 638 AM CDT TUE MAR 24 2015
Initial concern will be light freezing rain at SPI and DEC through
14z. Surface temperatures will be right around the freezing mark
through this time frame so some light icing is not out of the
question before temperatures edge into the middle 30s by mid to
late morning. Further north and east, the latest short term models
suggest the precip may struggle to shift north before 15z so will
hold back the precip threat up at PIA and BMI until after 15z. By
then, it appears the precip would be mostly rain with the
possibility for some isolated convection over parts of west
central and central IL during the morning. For now, will hold off
mentioning any -tsra during the morning, with the better threat for
isolated thunderstorms coming along this evening, as low pressure
passes across IL. MVFR and local IFR cigs will prevail thru most
of this forecast period with periods of rain through this
evening. Rain should come to an end from SW to NE as the low pulls
away into Indiana after midnight.
Surface winds will remain out of the east today, with a gradual
turn into the southeast and then south this evening as the surface
low approaches our area. Wind speeds will range from 12 to 17 kts
with gusts around 22 kts at times this afternoon and early this
evening.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
350 AM CDT TUE MAR 24 2015
.SHORT TERM...
249 AM CDT
THROUGH TONIGHT...
IR IMAGERY EARLY THIS MORNING INDICATED THE STRATUS LAYER HAS
PUSHED WEST OF THE CHICAGO AREA...HOWEVER A FEW POCKETS OF STRATUS
HAVE BEEN REDEVELOPING AND SLIDING ACROSS FAR NORTHEAST IL. TEMPS
ARE GENERALLY REMAINED IN THE UPR 20S EARLY THIS MORNING...WITH A
FEW LOCATIONS RADIATING INTO THE LOW 20S. A NARROW CHANNEL OF
CIRRUS WAS ALREADY STREAMING NORTHEAST FROM THE DEVELOPING
SHORTWAVE CURRENTLY CENTERED OVER THE CENTRAL PLAINS. THE GRADIENT
WILL REMAIN LIGHT THROUGH DAYBREAK...HOWEVER THE WEAK DIFFLUENT
FLOW WILL QUICKLY DISSIPATE AND MIXING WILL STEADILY INCREASE BY
MID-MORNING. GUIDANCE INDICATES SPEEDS THROUGH THE CHANNEL ARND
20KT.
THE MOIST AXIS DOES APPEAR TO BE SLIGHTLY SLOWER TO ARRIVE ACROSS
NORTHEAST IL UNTIL AFT 21Z...SO HAVE NUDGED TIMING BACK AN HOUR OR
TWO. COULD SEE PRECIP PUSHING INTO THE FAR SOUTHWEST CWFA ARND 18-
20Z...HOWEVER WITH THE WEAK DIFFLUENT FLOW LINGERING FURTHER
NORTH...THIS MAY HELP TO HOLD-OFF PRECIP UNTIL CLOSER TO 00Z. WITH A
STEADY CONVEYOR OF SLIGHTLY WARMER AIR ADVECTING NORTH THIS
AFTN...TEMPS ARE EXPECTED TO WARM TO ARND 40. THE CONCERN IS THAT
WITH THE FRESH SNOWPACK THIS MAY HOLD TEMPS DOWN A DEGREE OR TWO.
TONIGHT...
AS ELUDED TOO ABOVE...PRECIP WILL BE STEADILY INCREASING IN
COVERAGE THIS EVENING. BUT THE MAIN CONCERN FOR TONIGHT WILL
REVOLVE AROUND CONVECTION AND POSSIBLY SOME STRONGER EMBEDDED
THUNDERSTORMS. MID- LVL SHEAR IS IMPRESSIVE THIS EVENING...WITH
VALUES NEARING 40-50KTS. GIVEN THE RATHER MOIST PROFILE AND CLOUDY
ENVIRONMENT...CAPE VALUES WILL REMAIN MINIMAL. 0-3KM BULK SHEAR IS
EQUALLY IMPRESSIVE WITH THIS DYNAMIC NEGATIVELY TILTED SHORTWAVE
TONIGHT. THE SPC HAS THE AREAS SOUTH OF PONTIAC TO FOWLER IN A
MARGINAL RISK FOR SEVERE STORMS TONIGHT.
DEW POINTS WILL BE STEADILY INCREASING THIS EVENING AS WELL...AS
WARM AIR CONTINUES TO ADVECT NORTH. BY LATE THIS EVENING DEW POINTS
WILL BE APPROACHING THE LOW/MID 30S...AND POSSIBLY NEAR 40 ACROSS
THE FAR SOUTH. THEN OVERNIGHT DEW POINTS WILL CONTINUE TO RISE INTO
THE MID/UPR 30S NORTH...AND LOW 40S SOUTH. THIS SHOULD AID IN EATING
INTO THE SNOWPACK RATHER QUICKLY...COUPLED WITH THE RAIN AS WELL.
PWAT VALUES WILL BE NEARING 1 INCH LATE TONIGHT...AS THE MOISTURE
TRANSPORT CONTINUES TO FEED NORTH ACROSS THE FORECAST AREA. CURRENT
TRACK OF THE SHORTWAVE IS TO LIFT NORTHEAST ACROSS PONTIAC TO GARY
BY 9Z...WHICH SHUD HELP PUSH CONVECTIVE COVERAGE EAST/NORTHEAST BY
DAYBREAK WED.
BEACHLER
&&
.LONG TERM...
350 AM CDT
WEDNESDAY NIGHT THROUGH MONDAY...
THE MAIN STORY DURING THE LONGER TERM PERIOD WILL BE THE AMPLIFYING
UPPER LEVEL FLOW PATTERN ACROSS NORTH AMERICA. UPPER LEVEL RIDGING
IS FORECAST TO BUILD OVER THE WESTERN CONUS IN RESPONSE TO THE
PROGRESSION A SIGNIFICANT DISTURBANCE OVER THE NORTHERN
PACIFIC...AND THIS WILL ULTIMATELY DRIVE SIGNIFICANT HEIGHT FALLS
AND TROUGHING OVER THE THE EASTERN HALF OF THE CONUS. AS A
RESULT...EXPECT TO TRANSITION BACK TO A PERIOD OF MUCH BELOW AVERAGE
TEMPERATURES LATE THIS WEEK INTO THE FIRST HALF OF THE WEEKEND.
THE PERIOD WILL START OUT MILD ON WEDNESDAY FOLLOWING THE PASSAGE OF
THE TUESDAY NIGHT STORM SYSTEM. IT DOES APPEAR THAT CLOUD COVER
COULD LINGER DURING THE DAY ON WEDNESDAY...AND THIS COULD LIMIT THE
AMOUNT OF WARMING WE EXPERIENCE DURING THE DAY. HOWEVER...WITH THE
COLDER AIRMASS NOT ARRIVING ACROSS THE AREA UNTIL LATER WEDNESDAY
NIGHT TEMPERATURES SHOULD BE ABLE TO CLIMB TO...AT LEAST...NEAR 50
DEGREES. AREAS SOUTH OF INTERSTATE 80 STAND THE BEST CHANCES TO
CLIMB WELL INTO THE 50S.
AS A COLD FRONT BEGINS TO SHIFT ACROSS NORTHERN ILLINOIS WEDNESDAY
NIGHT A WEAK SURFACE WAVE OF LOW PRESSURE IS EXPECTED TO DEVELOP
OVER THE SOUTHERN PLAINS...BEFORE QUICKLY SHIFTING NORTHEASTWARD
ALONG THE FRONT INTO THURSDAY MORNING. INCREASING FGEN ALONG THIS
FRONTAL WAVE SHOULD RESULT IN PRECIPITATION DEVELOPMENT WEDNESDAY
NIGHT...PRIMARILY ACROSS MY EAST CENTRAL ILLINOIS AND NORTHWESTERN
INDIANA COUNTIES. THIS ACTIVITY WILL SHIFT TO THE SOUTH AND EAST OF
MY AREA BY EARLY THURSDAY MORNING AS THE COLD FRONT CONTINUES TO
SHIFT SOUTHEASTWARD. DRY BUT COOLER WEATHER IN THE LOW TO 40S IS
EXPECTED FOR THE DAY THURSDAY.
ANOTHER STRONGER PUSH OF COLD AIR WILL ARRIVE OVER THE AREA BY
THURSDAY NIGHT INTO FRIDAY AS YET ANOTHER COLD FRONT SHIFTS OVER THE
AREA. STEEPENING LOW LEVEL LAPSE RATES OVER LAKE MICHIGAN WITH THIS
COLD AIR MASS COULD EVEN RESULT IN SOME LAKE EFFECT SNOW SHOWERS
ACROSS NORTHEASTERN ILLINOIS AND NORTHWESTERN INDIANA INTO FRIDAY
MORNING...AND THIS ACTIVITY LOOKS AS THOUGH IT COULD BE COMPLIMENTED
BY ANOTHER UPPER LEVEL PV ANOMALY DIGGING INTO THE BASE OF THE UPPER
LEVEL TROUGH OVER THE AREA. IF THIS SCENARIO PANS OUT AS CURRENTLY
FORECAST...THERE COULD BE SOME MINOR SNOW ACCUMULATIONS ACROSS
PORTIONS OF THE AREA WITH THIS ACTIVITY INTO FRIDAY.
WITH THE HEART OF THE COLD AIR MASS EXPECTED TO BE OVERHEAD ON
FRIDAY...IT LOOKS TO BE THE COLDEST DAY. HIGH TEMPERATURES ARE
CURRENTLY ONLY FORECAST TO GET INTO THE LOWER TO MID 30S...WHICH IS
A GOOD 15 TO 20 DEGREES BELOW AVERAGE. SURFACE HIGH PRESSURE SHOULD
BECOME CENTERED OVER OR NEAR THE AREA BY LATE FRIDAY NIGHT...SO THIS
SHOULD ALLOW TEMPERATURES FRIDAY NIGHT TO DROP INTO THE TEENS
INTO SATURDAY MORNING OUTSIDE OF CHICAGO.
AFTER ANOTHER WELL BELOW AVERAGE DAY ON SATURDAY...THINGS LOOKS TO
WARM BACK UP BY SUNDAY SURFACE RIDGE SHIFTS OVER THE SOUTHEASTERN
CONUS. IT APPEARS THAT SUNDAY COULD END UP NOT ONLY BEING A WARMER
DAY...WITH HIGHS POTENTIALLY WARMING BACK UP NEAR OR JUST ABOVE
AVERAGE...BUT ALSO A VERY BREEZY DAY. FORECAST GUIDANCE SUGGESTS
THAT A POTENT CLIPPER SYSTEM WILL TRACK EAST-SOUTHEASTWARD OVER
SOUTHERN ONTARIO...WHICH COULD SET UP A SURFACE GRADIENT SUPPORTIVE
OF SOME STRONG SOUTHWESTERLY WINDS. IN ADDITION...THE INCREASING WARM
AIR ADVECTON REGIME OVER THE AREA COULD ALSO RESULT IN THE
DEVELOPMENT OF SOME LIGHT RAIN SHOWERS DURING THE DAY.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* PATCHY MVFR CIGS THRU 8Z...HOWEVER SHUD BE SOUTHWEST OF ORD/MDW.
* EAST WINDS PERSIST BETWEEN 5-8KT...INCREASING AFT DAYBREAK.
* WINDS TURN SOUTHEAST AND INCREASE MID-MORNING...SPEEDS BETWEEN
12-15KT WITH GUSTS UP TO 20KT.
* RAIN DEVELOPS LATE AFTN/EARLY EVE...WITH STEADIER RAIN AFT 00Z
WED. EMBEDDED THUNDER POSSIBLE AFT 00Z WED. IFR CIGS DEVELOP.
* LLWS POSSIBLE LATE TONIGHT...AOA 2KFT AGL SPEEDS INCREASE TO
50KT FROM SOUTHEAST AFT 2Z WED.
BEACHLER
//DISCUSSION...UPDATED 06Z...
HIGH PRESSURE REMAINS CENTERED TO THE NORTHEAST OF THE
REGION...ALLOWING LIGHT EASTERLY FLOW TO PERSIST. DRY AIR HAS BEEN
ABLE TO PUSH STRATUS FURTHER WEST AND SCOUR THE LOW CLOUDS FOR
ORD/MDW/GYY. EXPECT THIS TO SLOWLY PUSH FURTHER WEST OVERNIGHT AND
REACH RFD ARND 8Z. DEVELOPING LOW PRESSURE SYSTEM CONTINUES TO BE
POISED TO ARRIVE ACROSS THE REGION TUESDAY EVENING...WITH RAIN
OVERSPREADING THE TAF SITES LATE IN THE AFTN/EARLY EVE. CURRENT
GUIDANCE INDICATES THAT MVFR CIGS WILL REDEVELOP AFT 22Z AS THE
STEADIER RAIN NEARS THE TAF SITES. THE GRADIENT WILL QUICKLY
INCREASE LATE THIS MORNING...WITH GUSTS NEARING 20KT FROM THE
SOUTHEAST. EXPECT GUSTS TO CONTINUE THRU TONIGHT. LLWS WILL
ACCOMPANY THE LOW PRESSURE SYSTEM...WITH SPEEDS NEARING 50KT AT
2KFT AGL. EXPECT SOME GUSTS OF 20-24KT AT THE SFC.
RAIN WILL PUSH OVER THE TAF SITES...WITH BETTER INSTABILITY
ARRIVING. AT THIS TIME HAVE HELD OFF ON INCLUDING TSRA WITHIN THE
TAF...HOWEVER A FEW EMBEDDED THUNDERSTORMS MAY ACCOMPANY THE
STEADIER RAIN. THUNDER WILL LIKELY REMAIN ISOLATED THRU 09Z...THEN
THE BETTER INSTABILITY DECREASES WITH STEADIER RAIN BEGINNING TO
DISSIPATE SHORTLY BEFORE DAYBREAK WED.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* HIGH CONFIDENCE IN CIGS THRU 20Z...MEDIUM CONFIDENCE IN TIMING
OF MVFR/IFR CIGS AFT 00Z WED.
* HIGH CONFIDENCE IN RAIN DEVELOPING AFT 22Z...LOW CONFIDENCE IN
PRECISE TIMING. MEDIUM/LOW IN THUNDER TIMING AND COVERAGE
OVERNIGHT INTO EARLY WED MORNING.
* MEDIUM/HIGH CONFIDECE IN LLWS DEVELOPING AND MEDIUM CONFIDENCE
IN SPEEDS OF LLWS.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...SLIGHT CHANCE OF SHOWERS WITH MVFR CIGS EARLY AM.
OTHERWISE PRIMARILY VFR. BREEZY SOUTHWEST WINDS.
THURSDAY...SLIGHT CHANCE OF SHOWERS. MVFR POSSIBLE.
FRIDAY...SLIGHT CHANCE OF LIGHT SNOW EARLY. OTHERWISE PRIMARILY
VFR.
SATURDAY...VFR.
SUNDAY...CHANCE OF RAIN. PATCHY MVFR POSSIBLE.
RATZER
&&
.MARINE...
212 PM CDT
HIGH PRESSURE CENTERED OVER EAST-CENTRAL ONTARIO WILL MOVE
SOUTHEAST INTO NEW ENGLAND BY TUESDAY EVENING. THIS WILL ALLOW
EASTERLY WINDS TO SHIFT SOUTHEASTERLY THROUGH THE DAY TUESDAY. LOW
PRESSURE WILL DEVELOP IN THE LEE OF THE ROCKIES THROUGH THE DAY
TUESDAY IN RESPONSE TO AN UPPER LEVEL TROUGH WORKING EASTWARD. ONE
SURFACE LOW WILL CONSOLIDATE ACROSS THE DAKOTAS THEN BE KICKED
EASTWARD BY A SECOND UPPER TROUGH WEDNESDAY. OF MORE IMMEDIATE
NOTE IS THE SURFACE LOW THAT WILL DEVELOP ACROSS THE MID
MISSISSIPPI RIVER VALLEY AND TRACK NORTHEAST FROM THERE LATE
TUESDAY. GUIDANCE HAS STRUGGLED WITH THE STRENGTH AND TRACK OF
THIS LOW WITH MORE OF A SOUTHWARD TRACK FAVORED WHICH TAKES THE
LOW ACROSS SOUTHERN LAKE MICHIGAN. WITH SEVERAL FEATURES IN PLAY
IN TERMS OF THE DEVELOPMENT OF THIS SYSTEM WOULD NOT BE SURPRISED
TO SEE FURTHER FLUCTUATIONS IN THE TRACK/STRENGTH YET TONIGHT AND
TUESDAY MORNING. ALL OF THE ABOVE POINTS TO WINDS THAT ARE NOT AS
STRONG AS THEY APPEARED FOR LAND AND NEARSHORE AREAS...BUT OPEN
WATER AREAS STILL LOOK TO PUSH 30 KT AT TIMES LATE TUESDAY NIGHT
AND WEDNESDAY MORNING...WITH THE STABLE LAYER LIMITING WINDS MUCH
HIGHER THAN THAT SHOULD THE LOW END UP BEING STRONGER. WINDS WILL
BE EASTERLY NORTH OF THE TRACK AND SOUTHERLY SOUTH OF IT WITH A
MORE UNIFORM SOUTHWESTERLY WIND BEHIND THE LOW FOR MUCH OF
WEDNESDAY. THE DAKOTAS LOW WEAKENS AND MOVES ACROSS UPPER MICHIGAN
AND NORTHERN LAKE MICHIGAN WEDNESDAY EVENING WHILE A COLD FRONT
SWEEPS DOWN THE LAKE TURNING WINDS WEST TO NORTHWEST. A STEADY
PRESSURE GRADIENT WILL REMAIN ACROSS THE LAKE THURSDAY AHEAD OF
HIGH PRESSURE WHICH WILL MOVE FROM CENTRAL CANADA TO THE UPPER
MISSISSIPPI RIVER VALLEY BY FRIDAY AND ACROSS THE WESTERN LAKES
FRIDAY NIGHT. BREEZY NORTH TO NORTHWEST WINDS WILL GRADUALLY
DIMINISH DURING THIS TIME. LOW PRESSURE IS THEN EXPECTED TO TRACK
NORTH OF THE AREA EARLY SUNDAY WITH BREEZY SOUTHWEST WINDS
DEVELOPING AHEAD OF IT SHIFTING NORTHWEST AS ANOTHER HIGH MOVES
INTO THE PLAINS MONDAY.
MDB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-
LMZ745...7 PM TUESDAY TO 4 PM WEDNESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
330 AM CDT Tue Mar 24 2015
.SHORT TERM...(Today)
ISSUED AT 329 AM CDT TUE MAR 24 2015
A band of mid-level warm frontogenesis will advance into central IL
from the west this morning, causing rain showers to eventually
develop through the dry low level airmass. The leading edge of the
rain band will likely encounter areas with surface temps at or just
below freezing, but not sure how far south will freezing rain
affect. 08z obs show only Jacksonville and Lawrenceville above
freezing, while the remainder of our C and SE IL obs at or below
freezing. Will need to include a mention of freezing rain a bit
farther south this morning as a result. Road surface temps on IDOT
sites showing road temps ranging from 34 to as low as 31F. We could
see some slippery road conditions develop with this initial rain
falling on dry pavement. Air temperatures should rise above freezing
across the board by 15z/10am, so any icing would melt quickly.
However, any ice on initially dry roads can be very slippery.
Will follow the HRRR depiction of rain advancing eastward in a band
that matches the current radar trends rather closely. Likely and
categorical PoPs this morning will be confined to the western
counties where low level saturation will occur the soonest.
The band of warm F-gen will gradually shift north this afternoon,
giving the precip a northward push as well. Have kept likely PoPs
across the northern half of our area through the afternoon.
Instability params support elevated thunderstorms today, generally
in the southwest half of our forecast area.
High temps today will be held in check by the cool east-northeast
flow that will persist through the day. Most areas will see the
mid-upper 40s this afternoon.
&&
.LONG TERM...(Tonight through Monday)
ISSUED AT 329 AM CDT TUE MAR 24 2015
Deepening surface low pressure currently at 1006 mb over the OK
panhandle to eject ne into the IL river valley over central IL by
06Z/1 am tonight and then to southern part of Lake MI by 12Z/7 am
Wed and swing a cold front through central and eastern IL overnight.
Showers likely ahead of this front along with chances of
thunderstorms. SPC has marginal risk over much of central IL
(excluding Knox, Stark and Marshall counties) with slight risk of
severe storms this evening across central and sw MO from St Louis
southwest. Lows tonight range from upper 30s to near 40F over IL
river valley to upper 40s and lower 50s in southeast IL.
Central IL to be inbetween weather systems during the day Wed as low
pressure passes ne of the Great Lakes and another surface low
pressure organizes over the southern plains. Isolated showers and
thunderstorms to be possible later Wed afternoon south of I-72.
Milder highs Wed mostly in the 60s, ranging from around 60F from
Peoria north to upper 60s and lower 70s in southeast IL. 1007 mb low
pressure to track ne into far southern IL by 06Z/1 AM Wed night and
up the Ohio river to near the OH/KY border by dawn Thu. Models have
trended further south with this low pressure track, and SPC has
shifted slight risk of severe storms Wed night south of our CWA with
marginal risk into southeast counties along and south of I-70. Heavy
rains of 1-1.5 inches possible south of I-70 Wed night while rain
chances taper off to 20-30% nw of the IL river. Lows Wed night range
from mid 30s over IL river valley to 40-45F in southeast IL from I-70
southeast.
Lingered a chance of rain showers in southeast IL Thu morning then
low pressure moves into southcentral PA by midday Thu and far enough
way to end rain chances Thu afternoon. Much cooler highs Thu in the
mid to upper 40s central IL and near 50F southeast IL. Even colder
Friday with highs in the upper 30s and lower 40s, coolest from I-74
ne. Models have been consistent in digging strong upper level trof
into the eastern states Thu/Fri bringing in the very cool
temperatures. 1030 mb Canadian high pressure settles into the Great
Lakes region Fri night and Sat with clouds and winds decreasing and
continued cold temps. Lows Fri night in the low to mid 20s. Highs
Sat in the low to mid 40s.
A cutoff upper level low passes north of the Great Lakes Sunday
keeping best chances of precipitation north of central IL, though
did carry small chances of light rain showers Sunday. Milder highs
Sunday and Monday in the mid to upper 50s with west central IL
around 60F.
&&
.AVIATION...(For the 06Z TAFS through 06Z Tuesday night)
ISSUED AT 1105 PM CDT MON MAR 23 2015
Main concern will be with the threat for a brief period of light
freezing rain at SPI and possibly as far east as DEC in the 10z-
14z time frame. Surface temperatures will be right around the
freezing mark through this time frame so some light icing is not
out of the question before temperatures edge into the middle 30s
by mid to late morning. Further north and east, the latest short
term models suggest the precip may struggle to shift north before
15z so will hold back the precip threat up at PIA and BMI until
after 15z. By then, it appears the precip would be mostly rain
with the possibility for some isolated convection over parts of
west central and central IL during the morning. For now, will hold
off mentioning any -tsra during the morning withe better threat
for isolated thunderstorms coming along tomorrow night. MVFR and
local IFR cigs will prevail thru most of this forecast period with
periods of rain into tomorrow evening as a storm system is
expected to track right over our area Tuesday night.
Surface winds will remain out of the northeast to east tonight at
10 to 15 kts and then easterly winds will prevail Tuesday with a
gradual turn into the southeast and then south Tuesday evening as
the surface low approaches our area. Wind speeds tomorrow will
range from 12 to 17 kts with gusts around 22 kts at times,
especially during the afternoon and evening hours.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Shimon
LONG TERM...07
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1147 PM CDT MON MAR 23 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 339 PM CDT MON MAR 23 2015
OVERNIGHT FORECAST BECOMING COMPLICATED BY STRATUS DEVELOPMENT
TODAY AND MUCH COOLER HIGHS THAN ANTICIPATED. WITH NORTHEAST FLOW
AT THE SURFACE...DEW POINTS WILL REMAIN IN THE MID TO UPPER 20S FOR
THE OVERNIGHT HOURS UNTIL WINDS BECOME MORE SOUTHEAST AFTER 06Z. THIS
SHOULD ACT TO CAP ANY COOLING OVER THE SOUTH AND ACTUALLY RESULT IN
A EITHER STEADY OR A SLOW RISE IN TEMPERATURE AND DEW POINTS OVER
THE REGION BY 12Z. SOUNDINGS CONTINUE TO SHOW DRY AIR IN THE
FORECAST AREA WILL NEED TO BE OVERCOME PRIOR TO ANY PRECIPITATION
REACHING THE GROUND. THE GFS/NAM ARE MOST AGGRESSIVE WITH
SATURATION...THOUGH THE GFS HAS BACKED OFF A BIT ON THE ONSET OF
PRECIPITATION. THE EURO HAS BEEN SIMILAR IN THE PAST 2 MODEL
SOLUTIONS IN DELAYING MOST OF THE PRECIPITATION WITH THE EXCEPTION
OF THE FAR SOUTH UNTIL 09-12Z. AFTER LOOKING AT THE HRRR AND SEEING
THAT THE MESO SCALE MODELS ARE CONTINUING WITH AN EARLIER
ONSET...HAVE TAKEN A BLEND OF THE EURO/GFS SOLUTIONS. BACKED OFF A
BIT ON THE ONSET FROM THE PREVIOUS PACKAGE AND ALSO HAVE TRIMMED
BACK THUNDER CHANCES OVER THE SOUTH WITH ONLY THE FAR SOUTH LIKELY
TO SEE ANY ISO THUNDER THROUGH 12Z. THOUGH MOST OF ANY PRECIPITATION
THAT FALLS SHOULD REMAIN LIQUID...THERE IS STILL A RISK FOR SOME
LIGHT FREEZING RAIN ON THE NORTHERN EDGE OF THE PRECIPITATION SHIELD
AND OVER SOUTHEAST SECTIONS AS THE PRECIPITATION COMMENCES. THIS IS
MAINLY DUE TO TODAYS LACK OF DAYTIME HEATING...THE RELATIVELY DRY
AIR AND THE EXPECTATION THAT OVERNIGHT LOWS OVER THOSE AREAS WILL
LIKELY BE AT OR JUST BELOW THE FREEZING MARK BY SUNRISE. WITH
LIMITED MOISTURE EXPECTED OVERNIGHT...WILL NOT HAVE ANY HEADLINES AT
THIS TIME DUE TO THE POTENTIAL OF MAINLY VERY LIGHT ACCUMULATIONS OF
A HUNDREDTH OR TWO. LOWS WILL RANGE FROM THE 20S NORTHEAST TO THE
LOWER TO MID 30S OVER THE SOUTHWEST.
.LONG TERM /TUESDAY THROUGH MONDAY/...
ISSUED AT 339 PM CDT MON MAR 23 2015
PRECIPITATION EXPECTED TO BE ONGOING ACROSS THE SOUTHERN HALF OF
THE CWA AND WILL CONTINUE TO SPREAD NORTH ACROSS THE REMAINDER OF
THE CWA TUESDAY AS A DOUBLE-BARRELED UPPER LEVEL SYSTEM IMPACTS
THE REGION. INITIAL WAVE ROTATING THROUGH THE BASE OF THE OTHER
LOW TO SWING THROUGH IOWA LATE TUESDAY INTO TUESDAY NIGHT BRINGING
THE MAJORITY OF THE CHANGES OF PRECIPITATION THROUGH WEDNESDAY
NIGHT. WARM FRONT ALOFT TO LIFT NORTHWARD THROUGH THE CWA...WAA
AND MOISTURE ADVECTION IN PLACE ACROSS MUCH OF THE AREA TUESDAY.
STILL EXPECTING A MAIN AREA OF WAA PRECIP TO LIFT THROUGH THE CWA
TUESDAY MORNING...WITH A DRY PERIOD ACROSS PORTIONS OF
CENTRAL/SOUTHERN IOWA MOST LIKELY LATER TUESDAY MORNING INTO EARLY
AFTERNOON. SHOWER AND POTENTIAL ISOLATED THUNDERSTORM
REDEVELOPMENT EXPECTED IN THE AFTERNOON HOURS...AS THE MAIN UPPER
LOW MOVES OVERHEAD. WIDESPREAD PRECIPITATION EXPECTED ACROSS THE
ENTIRE CWA WITH THE MAIN LOW MOVING THROUGH...WITH PRECIPITATION
EXPECTED TO TAPER OFF FROM WEST TO EAST TUESDAY EVENING AS THE
UPPER LOW PUSHES EAST NORTHEAST INTO THE GREAT LAKES REGION.
CONTINUE TO SEE CHANCES FOR ELEVATED THUNDER ACROSS THE SOUTHERN
HALF OF THE CWA TUESDAY INTO TUESDAY EVENING. DYNAMIC COOLING OF
THE COLUMN WITH MORE INTENSE PRECIPITATION AREAS SHOULD ALLOW FOR
A MIXING OF RAIN/SNOW OR COMPLETE CHANGEOVER TO ALL SNOW ACROSS
THE FAR NORTHERN AREAS LATE TUESDAY AFTERNOON INTO TUESDAY
EVENING. A QUICK INCH OR TWO OF SNOW IS POSSIBLE BEFORE
PRECIPITATION CHANCES TAPER OFF TUESDAY EVENING. WIDESPREAD HALF
INCH QPF AMOUNTS CAN BE EXPECTED FROM THIS SYSTEM.
SECOND LOBE OF THE UPPER LEVEL SYSTEM TO DROP SOUTHWARD TOWARD THE
AREA WEDNESDAY...WITH A COLD FRONT DROPPING THROUGH THE CWA. MAY
HAVE SOME PRECIPITATION FORM ALONG AND AHEAD OF THE COLD FRONT BY
LATE AFTERNOON ACROSS FAR SOUTHERN IOWA. ARCTIC HIGH PRESSURE TO
THEN BUILD INTO THE REGION FOR THURSDAY INTO FRIDAY...WITH H85
TEMPS DROPPING INTO THE TEENS BELOW CELSIUS. THIS SHOULD ALLOW
TEMPS ACROSS THE AREA TO REMAIN WELL BELOW AVERAGE TO CLOSE OUT
THE WEEK. THE HIGH QUICKLY SHOVES SOUTHEAST THROUGH AS THE THERMAL
RIDGE BUILDS IN ALOFT OVER THE UPCOMING WEEKEND WITH UPPER LEVEL
RIDGING BUILDING INTO THE CENTRAL US. THEREFORE TEMPS SHOULD WARM
BACK TO NEAR THE SEASONAL AVERAGES OR ABOVE BY SUNDAY AND INTO
EARLY NEXT WEEK.
&&
.AVIATION...24/06Z
ISSUED AT 1144 PM CDT MON MAR 23 2015
LOW CEILINGS WILL REMAIN FOR MUCH OF THE FORECAST WITH MVFR TO IFR
CEILINGS THROUGH TUESDAY EVENING AS MOIST EASTERLY NEAR SURFACE
FLOW PERSISTS. ANTICIPATE SOME CONVECTION MOVING INTO SOUTHERN
IOWA LATE TONIGHT AND SPREADING NORTHWARD DURING THE DAY. ISOLD TO
SCT CONVECTION SEEMS POSSIBLE THROUGH TOMORROW EVENING WITH
ELEVATED INSTABILITY ALTHOUGH DIDNT HIT IT TOO HARD YET IN THE
TAF SINCE IT IS A WAYS OUT. VISIBILITIES WILL SEE SOME
RESTRICTIONS INTO TUESDAY AS WELL WITH THE RAIN AND SOME LIGHT
FOG. OVERALL...GENERALLY FAIR TO POOR CONDITIONS FOR AVIATION
THROUGH THE PERIOD.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...REV
LONG TERM...BEERENDS
AVIATION...COGIL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
219 AM CDT TUE MAR 24 2015
...UPDATED FOR LONG TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 150 AM CDT TUE MAR 24 2015
NAM BUFR SOUNDINGS INDICATING A 3000 TO 3500FT AGL MOIST LAYER
NEAR THE SURFACE ACROSS NORTH CENTRAL KANSAS EARLY THIS MORNING.
THIS MOISTURE ALONG WITH SOME WEAK LIFT IN LAYER WILL BE OCCURRING
UNDER A LAYER OF WARM 800 TO 700MB TEMPERATURES THROUGH 15Z. WILL
THEREFORE TREND TOWARDS HIGH CHANCES FOR LIGHT PRECIPITATION EARLY
THIS MORNING NORTH OF HIGHWAY 96. WILL ALSO KEEP A MENTION OF
THUNDER GOING GIVEN THE IMPROVING INSTABILITY EXPECTED UNDER THE
500MB COOL POOL THAT WILL BE CROSSING WESTERN KANSAS BETWEEN 12Z
AND 18Z TUESDAY.
FOR THE REMAINDER OF THE DAY...THE MODELS THIS MORNING STILL
INDICATING A MIXED LAYER DEPTH UP TO AROUND THE 750MB LEVEL DURING
THE AFTERNOON. USING THESE TEMPERATURES AS A GUIDE TODAY FOR HIGHS
TODAY THE CURRENT FORECAST WILL LOOKS ON TRACK WITH HIGHS MAINLY
IN THE LOW TO MID 70S. 00Z NAM AND 00Z GFS BOTH INDICATED THIS
MORNING THAT THE MEAN MIXED LAYER WINDS IN THIS DEPTH WILL NOT AS
STRONG AS WHAT THE PREVIOUS RUNS SUGGESTED. WILL HAVE SOME 35 TO
45 KNOTS IN THE 850MB TO 800MB LEVEL EARLY THIS MORNING BUT BY 18Z
THE MEAN WIND SPEEDS ARE FORECAST TO WEAKEN INTO THE 25 TO 35 KNOT
RANGE. THIS STILL SUGGESTS A PERIOD OF GUSTY NORTHWEST WIND AT 20
TO NEAR 30 MPH EARLY THIS AFTERNOON, MAINLY ACROSS NORTHWEST AND
SOUTH CENTRAL KANSAS. GIVE THESE EXPECTED WINDS ALONG WITH THE
RELATIVE HUMIDITY VALUES RANGING FROM 10 TO 15 PERCENT DURING THE
AFTERNOON HOURS WILL CONTINUE TO HIGHLIGHT CRITICAL FIRE WEATHER
CONDITIONS TODAY AND KEEP THE RED FLAG WARNING GOING. A FEW AREAS
MAY STRUGGLE TO REACH THE WIND CRITERIA BUT IT WILL BE CLOSE.
TONIGHT ANOTHER UPPER LEVEL DISTURBANCE WILL EXIT THE PACIFIC
NORTHWEST AND MOVE INTO THE CENTRAL ROCKIES. AHEAD OF THIS
APPROACHING UPPER LEVEL SYSTEM MID AND HIGH LEVEL MOISTURE WILL
INCREASE ACROSS WESTERN KANSAS DURING THE OVERNIGHT HOURS. AS THIS
HIGH CLOUDS INCREASE ACROSS WESTERN KANSAS A COLD FRONT WILL BE
MOVING SOUTH OUT OF NEBRASKA AND INTO WESTERN KANSAS BY EARLY
WEDNESDAY MORNING. AT THIS TIME GIVEN THE LOCATION OF THE FRONT
EARLY WEDNESDAY MORNING AND THE EXPECTED CLOUD COVER WILL TREND
TOWARDS THE WARMER GUIDANCE FOR OVERNIGHT LOWS, ESPECIALLY IN
SOUTH CENTRAL KANSAS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 216 AM CDT TUE MAR 24 2015
FOR WEDNESDAY A SHORTWAVE TROUGH WILL BE SWINGING ACROSS THE CENTRAL
PLAINS WITH INCREASING CLOUDINESS AND A COLD FRONT. CHANCES FOR ANY
MEASURABLE PRECIP WILL BE NILL WITH THIS WAVE WITH ONLY MID LEVEL
MOISTURE AVAILABLE. HIGHS WILL BE GENERALLY FROM 60 TO 65 DEGREES
WITH GUSTY NORTH WINDS OF 20 TO 30 MPH BY AFTERNOON.
DRY NORTHWEST FLOW ALOFT FOLLOWS INTO NEXT WEEKEND. HIGHS WILL BE
AROUND 60 ON THURSDAY AS COLDER HIGH PRESSURE SETTLES INTO THE
CENTRAL PLAINS. AS THE COLD SURFACE HIGH RETREATS, WARMER WINDS FROM
THE SOUTH DEVELOP ON FRIDAY WITH HIGHS FROM 60 TO 65. A WARMING
TREND CONTINUES INTO THE WEEKEND WITH HIGHS IN THE 70S INTO EARLY
NEXT WEEK. OVERNIGHT LOWS LOOK TO RANGE FROM 30 TO 35 INTO FRIDAY
MORNING, THEN WARMING INTO THE 40S FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1202 AM CDT TUE MAR 24 2015
OVERNIGHT AS THE FIRST IN A SERIES OF UPPER LEVEL DISTURBANCES
CROSSES INTO CENTRAL KANSAS THE EASTERLY WINDS OVER SOUTHWEST
KANSAS WILL SHIFT TO THE NORTHWEST AND RANGE FROM 10 TO NEAR 15
KNOTS. AS THE WINDS SHIFT TO THE NORTH/NORTHWEST THE 00Z BUFR
SOUNDING DOES INDICATED THE THE MOISTURE NEAR THE SURFACE WILL
INCREASE. THE DEPTH OF THIS MOIST LAYER TOWARDS 12Z TUESDAY IN
HAYS WILL RANGE FROM 3000 TO 4000 FT AGL WHILE AT DDC AND GCK WILL
BE LESS THAN 1500FT AGL. GIVEN THE DEPTH OF THIS MOIST LAYER
BETWEEN 09Z AND 15Z TUESDAY THERE WILL BE A CHANCE FOR LIGHT
PRECIPITATION AS CEILINGS AND VISIBILITIES LOWER INTO THE MVFR/IFR
CATEGORY IN THE HYS AREA. FURTHER SOUTH HRRR AND BUFR SOUNDINGS
INDICATED THE POTENTIAL FOR A BRIEF PERIOD OF MVFR CEILINGS AND
MAINLY IN THE DDC AREA.
AFTER 12Z TUESDAY ANOTHER UPPER LEVEL DISTURBANCE WILL CROSS
WESTERN KANSAS AS AS THIS NEXT SYSTEM PASSES SKIES WILL CLEAR AND
GUSTY NORTHWEST WINDS WILL DEVELOP. ACROSS ALL OF WESTERN KANSAS
THE GUSTY NORTHWEST WINDS WILL RANGE FROM 20 TO NEAR 25 KNOT RANGE
BETWEEN 15Z AND 21Z TUESDAY AND THEN GRADUALLY FALL BACK INTO THE
10 TO 15 KNOT RANGE BY 00Z WEDNESDAY.
&&
.FIRE WEATHER...
ISSUED AT 150 AM CDT TUE MAR 24 2015
GUSTY NORTHWEST WINDS WILL DEVELOP BY LATE MORNING AND CONTINUE
THROUGH THE LATE AFTERNOON. SUSTAINED WIND SPEEDS OF 20 TO NEAR 30
MPH CAN BE EXPECTED WITH HIGHER GUSTS POSSIBLE. IN ADDITION TO THE
INCREASING WINDS THE AFTERNOON RELATIVE HUMIDITY VALUES WILL FALL
BACK INTO THE 10 TO 15 PERCENT RANGE BY 3 PM. THE COMBINATION OF
THESE RELATIVE HUMIDITY VALUES AND VERY WINDY CONDITIONS WILL
CREATE A FAVORABLE ENVIRONMENT WHERE RAPID WILDFIRE GROWTH WILL
OCCUR. ANY OUTDOOR BURNING TODAY SHOULD BE AVOIDED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 72 40 65 32 / 0 0 10 10
GCK 71 38 62 30 / 0 0 10 10
EHA 71 41 63 34 / 0 0 10 10
LBL 73 40 65 33 / 0 0 10 10
HYS 70 39 60 30 / 30 0 10 10
P28 75 43 69 36 / 10 0 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ THIS AFTERNOON TO 7 PM
CDT /6 PM MDT/ THIS EVENING FOR KSZ030-031-043>046-061>066-
074>081-084>090.
&&
$$
SHORT TERM...BURGERT
LONG TERM...KRUSE
AVIATION...BURGERT
FIRE WEATHER...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
153 AM CDT TUE MAR 24 2015
...UPDATED SHORT TERM AND FIRE WEATHER DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 150 AM CDT TUE MAR 24 2015
NAM BUFR SOUNDINGS INDICATING A 3000 TO 3500FT AGL MOIST LAYER
NEAR THE SURFACE ACROSS NORTH CENTRAL KANSAS EARLY THIS MORNING.
THIS MOISTURE ALONG WITH SOME WEAK LIFT IN LAYER WILL BE OCCURRING
UNDER A LAYER OF WARM 800 TO 700MB TEMPERATURES THROUGH 15Z. WILL
THEREFORE TREND TOWARDS HIGH CHANCES FOR LIGHT PRECIPITATION EARLY
THIS MORNING NORTH OF HIGHWAY 96. WILL ALSO KEEP A MENTION OF
THUNDER GOING GIVEN THE IMPROVING INSTABILITY EXPECTED UNDER THE
500MB COOL POOL THAT WILL BE CROSSING WESTERN KANSAS BETWEEN 12Z
AND 18Z TUESDAY.
FOR THE REMAINDER OF THE DAY...THE MODELS THIS MORNING STILL
INDICATING A MIXED LAYER DEPTH UP TO AROUND THE 750MB LEVEL DURING
THE AFTERNOON. USING THESE TEMPERATURES AS A GUIDE TODAY FOR HIGHS
TODAY THE CURRENT FORECAST WILL LOOKS ON TRACK WITH HIGHS MAINLY
IN THE LOW TO MID 70S. 00Z NAM AND 00Z GFS BOTH INDICATED THIS
MORNING THAT THE MEAN MIXED LAYER WINDS IN THIS DEPTH WILL NOT AS
STRONG AS WHAT THE PREVIOUS RUNS SUGGESTED. WILL HAVE SOME 35 TO
45 KNOTS IN THE 850MB TO 800MB LEVEL EARLY THIS MORNING BUT BY 18Z
THE MEAN WIND SPEEDS ARE FORECAST TO WEAKEN INTO THE 25 TO 35 KNOT
RANGE. THIS STILL SUGGESTS A PERIOD OF GUSTY NORTHWEST WIND AT 20
TO NEAR 30 MPH EARLY THIS AFTERNOON, MAINLY ACROSS NORTHWEST AND
SOUTH CENTRAL KANSAS. GIVE THESE EXPECTED WINDS ALONG WITH THE
RELATIVE HUMIDITY VALUES RANGING FROM 10 TO 15 PERCENT DURING THE
AFTERNOON HOURS WILL CONTINUE TO HIGHLIGHT CRITICAL FIRE WEATHER
CONDITIONS TODAY AND KEEP THE RED FLAG WARNING GOING. A FEW AREAS
MAY STRUGGLE TO REACH THE WIND CRITERIA BUT IT WILL BE CLOSE.
TONIGHT ANOTHER UPPER LEVEL DISTURBANCE WILL EXIT THE PACIFIC
NORTHWEST AND MOVE INTO THE CENTRAL ROCKIES. AHEAD OF THIS
APPROACHING UPPER LEVEL SYSTEM MID AND HIGH LEVEL MOISTURE WILL
INCREASE ACROSS WESTERN KANSAS DURING THE OVERNIGHT HOURS. AS THIS
HIGH CLOUDS INCREASE ACROSS WESTERN KANSAS A COLD FRONT WILL BE
MOVING SOUTH OUT OF NEBRASKA AND INTO WESTERN KANSAS BY EARLY
WEDNESDAY MORNING. AT THIS TIME GIVEN THE LOCATION OF THE FRONT
EARLY WEDNESDAY MORNING AND THE EXPECTED CLOUD COVER WILL TREND
TOWARDS THE WARMER GUIDANCE FOR OVERNIGHT LOWS, ESPECIALLY IN
SOUTH CENTRAL KANSAS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 210 PM CDT MON MAR 23 2015
MEDIUM RANGE MODELS INDICATE AN UPPER LEVEL SHORTWAVE TRANSITIONING
EASTWARD OUT OF THE NORTHERN PLAINS INTO THE GREAT LAKES REGION
WEDNESDAY SENDING AN ATTENDANT COLD FRONT SOUTHWARD ACROSS WESTERN
KANSAS. HOWEVER, A FAIRLY WEAK FLOW ALOFT COMBINED WITH A LACK OF
LOW/MID LEVEL MOISTURE AND LITTLE INSTABILITY PRESENT WILL RESULT
IN GENERALLY DRY CONDITIONS ACROSS WESTERN KANSAS THROUGH THURSDAY
AFTERNOON, ALTHOUGH A FEW SPRINKLES/LIGHT RAIN CANNOT BE RULED OUT
BEHIND THE FRONT WEDNESDAY NIGHT. RIDGING ALOFT IS PROJECTED TO
PUSH ASHORE OFF THE PACIFIC THURSDAY SETTING UP A NORTHWEST FLOW
ALOFT ACROSS THE WESTERN HIGH PLAINS. AN OUTSIDE CHANCE FOR PRECIP
MAY PICK UP A LITTLE THURSDAY NIGHT AS AN H5 VORT MAXIMA TRACKS
SOUTHEAST ACROSS THE NORTHERN PLAINS. HOWEVER, LOW/MID LEVEL
MOISTURE WILL REMAIN MINIMAL AT BEST LIMITING PRECIP CHANCES TO A
FEW ISOLATED SHOWERS WITH THE POTENTIAL FOR A SNOW MIX LATE
THURSDAY NIGHT.
COOLER TEMPERATURES ARE LIKELY WEDNESDAY IN WAKE OF A COLD FRONT
PUSHING SOUTHWARD ACROSS WESTERN KANSAS. COLDER AIR FILTERING DOWN
INTO THE AREA WILL LOWER H85 TEMPERATURES FROM THE TEENS(C) THE DAY
PREVIOUS WELL DOWN INTO THE SINGLE DIGITS(C) BY WEDNESDAY AFTERNOON.
LOOK FOR HIGHS GENERALLY UP INTO THE 60S(F) WITH A FEW UPPER 50S(F)
POSSIBLE NEAR THE I-7O CORRIDOR AND NEAR 70F POSSIBLE IN SOUTH
CENTRAL KANSAS DEPENDING ON THE TIMING OF THE FRONT. EXPECT HIGHS
ONLY UP INTO THE 50S(F) ACROSS CENTRAL KANSAS THURSDAY AS SURFACE
HIGH PRESSURE ACROSS THE NORTHERN PLAINS CONTINUES TO HELP EDGE THE
COOLER AIR MASS FURTHER SOUTHWEST INTO THE HIGH PLAINS. NEAR 60F IS
STILL POSSIBLE IN EXTREME SOUTHWEST KANSAS. SIMILAR HIGH
TEMPERATURES ARE EXPECTED THROUGH THE END OF THE WEEK WITH THE AIR
MASS ACROSS THE HIGH PLAINS UNDERGOING LITTLE CHANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1202 AM CDT TUE MAR 24 2015
OVERNIGHT AS THE FIRST IN A SERIES OF UPPER LEVEL DISTURBANCES
CROSSES INTO CENTRAL KANSAS THE EASTERLY WINDS OVER SOUTHWEST
KANSAS WILL SHIFT TO THE NORTHWEST AND RANGE FROM 10 TO NEAR 15
KNOTS. AS THE WINDS SHIFT TO THE NORTH/NORTHWEST THE 00Z BUFR
SOUNDING DOES INDICATED THE THE MOISTURE NEAR THE SURFACE WILL
INCREASE. THE DEPTH OF THIS MOIST LAYER TOWARDS 12Z TUESDAY IN
HAYS WILL RANGE FROM 3000 TO 4000 FT AGL WHILE AT DDC AND GCK WILL
BE LESS THAN 1500FT AGL. GIVEN THE DEPTH OF THIS MOIST LAYER
BETWEEN 09Z AND 15Z TUESDAY THERE WILL BE A CHANCE FOR LIGHT
PRECIPITATION AS CEILINGS AND VISIBILITIES LOWER INTO THE MVFR/IFR
CATEGORY IN THE HYS AREA. FURTHER SOUTH HRRR AND BUFR SOUNDINGS
INDICATED THE POTENTIAL FOR A BRIEF PERIOD OF MVFR CEILINGS AND
MAINLY IN THE DDC AREA.
AFTER 12Z TUESDAY ANOTHER UPPER LEVEL DISTURBANCE WILL CROSS
WESTERN KANSAS AS AS THIS NEXT SYSTEM PASSES SKIES WILL CLEAR AND
GUSTY NORTHWEST WINDS WILL DEVELOP. ACROSS ALL OF WESTERN KANSAS
THE GUSTY NORTHWEST WINDS WILL RANGE FROM 20 TO NEAR 25 KNOT RANGE
BETWEEN 15Z AND 21Z TUESDAY AND THEN GRADUALLY FALL BACK INTO THE
10 TO 15 KNOT RANGE BY 00Z WEDNESDAY.
&&
.FIRE WEATHER...
ISSUED AT 150 AM CDT TUE MAR 24 2015
GUSTY NORTHWEST WINDS WILL DEVELOP BY LATE MORNING AND CONTINUE
THROUGH THE LATE AFTERNOON. SUSTAINED WIND SPEEDS OF 20 TO NEAR 30
MPH CAN BE EXPECTED WITH HIGHER GUSTS POSSIBLE. IN ADDITION TO THE
INCREASING WINDS THE AFTERNOON RELATIVE HUMIDITY VALUES WILL FALL
BACK INTO THE 10 TO 15 PERCENT RANGE BY 3 PM. THE COMBINATION OF
THESE RELATIVE HUMIDITY VALUES AND VERY WINDY CONDITIONS WILL
CREATE A FAVORABLE ENVIRONMENT WHERE RAPID WILDFIRE GROWTH WILL
OCCUR. ANY OUTDOOR BURNING TODAY SHOULD BE AVOIDED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 72 40 65 32 / 0 0 10 10
GCK 71 38 64 30 / 0 0 10 10
EHA 71 41 64 34 / 0 0 10 10
LBL 73 40 67 34 / 0 0 10 10
HYS 70 39 62 31 / 30 0 10 10
P28 75 43 68 36 / 10 0 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ THIS AFTERNOON TO 7 PM
CDT /6 PM MDT/ THIS EVENING FOR KSZ030-031-043>046-061>066-
074>081-084>090.
&&
$$
SHORT TERM...BURGERT
LONG TERM...JJOHNSON
AVIATION...BURGERT
FIRE WEATHER...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1207 AM CDT TUE MAR 24 2015
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1202 AM CDT TUE MAR 24 2015
AT 00Z TUESDAY ONE UPPER LEVEL TROUGH WAS LOCATED OVER SOUTHWEST
KANSAS WITH ANOTHER UPPER LEVEL SYSTEM BEING LOCATED OVER NORTHERN
COLORADO. FURTHER WEST A THIRD, STRONGER, UPPER LEVEL TROUGH WAS
EVIDENT FROM WATER VAPOR LOOP AND 500MB ANALYSIS OVER EASTERN
IDAHO/NORTHERN UTAH. THIS THIRD UPPER LEVEL TROUGH WAS ASSOCIATED
WITH THE LEFT EXIT REGION OF A 250MB JET STREAK. OVER THE
CENTRAL/SOUTHERN HIGH PLAINS AT 00Z TUESDAY AN AREA OF +5 TO +6C
700MB TEMPERATURES EXTENDED FROM EASTERN COLORADO INTO NORTH EAST
NEW MEXICO AND THE PANHANDLE OF TEXAS. THE NORTHERN EDGE OF THESE
WARM TEMPERATURES STRETCHED FROM NORTHEAST COLORADO INTO NORTH
WEST OKLAHOMA. AN 850MB WARM FRONT EXTENDED FROM SOUTHEAST
COLORADO INTO SOUTHWEST OKLAHOMA WITH A WEDGE OF HIGHER DEW POINTS
BEGIN LOCATED FROM DODGE CITY SOUTH AND SOUTHEAST. A SURFACE WARM
FRONT AT 00Z TUESDAY WAS LOCATED ALONG THE KANSAS AND OKLAHOMA
BORDER.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 333 PM CDT MON MAR 23 2015
MURPHY`S LAW IS IN EFFECT THIS EVENING. MORE IMPORTANTLY, TODAY ILLUSTRATES
HOW FICKLE MESOSCALE METEOROLOGY IS. THE WARM FRONT WITH ALL THE HIGHER
DEWPOINTS HAS BARELY MOVED NORTHWARD THIS AFTERNOON. IN ADDITION, CLOUDS
HAVE DEVELOPED ACROSS SOUTHWEST KANSAS KEEPING TEMPERATURES COOL. THE
NET RESULT IS THAT INSTABILITY IS NON-EXISTENT RIGHT NOW. HAVE SERIOUS
DOUBTS THAT ANY THUNDERSTORMS WILL FORM. I HAVE KEPT CHANCE POPS ACROSS
THE EASTERN ZONES JUST IN CASE THE 4 KM NAM IS CORRECT. AGAIN, IT WOULD
TAKE SOME SERIOUS AIR MASS MODIFICATION IN A SHORT PERIOD OF TIME FOR
EVENING THUNDERSTORMS. THERE MIGHT BE SLIGHTLY MORE CONDUCIVE METEOROLOGY
AFTER DARK AS THE LOW LEVEL JET STRENGTHENS. OTHER MODELS ARE SUGGESTING
WHAT I AM NOW THINKING... WE WON`T SEE SQUAT. SEVERE THUNDERSTORMS AND
HAIL ARE BECOMING VERY UNLIKELY AS WELL. LOWS TONIGHT WILL BE IN THE
40S. HIGHS TOMORROW WILL BE IN THE 70S. IT WILL BE WINDY AND DEWPOINTS
WILL MIX OUT. HAVE A RED FLAG WARNING FOR THE ENTIRE REGION AS A RESULT
AS CRITICAL FIRE WEATHER CONDITIONS ARE VERY LIKELY. DO NOT BURN TOMORROW.
OTHER THAN TONIGHT INTO THE OVERNIGHT HOURS, POPS WILL TREND TO ZERO
PERCENT BY THE EARLY AFTERNOON. THERE MAYBE SOME DRIZZLE IN THE MORNING,
BUT THIS ISN`T IN THE FORECAST DUE TO UNCERTAINTY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 210 PM CDT MON MAR 23 2015
MEDIUM RANGE MODELS INDICATE AN UPPER LEVEL SHORTWAVE TRANSITIONING
EASTWARD OUT OF THE NORTHERN PLAINS INTO THE GREAT LAKES REGION
WEDNESDAY SENDING AN ATTENDANT COLD FRONT SOUTHWARD ACROSS WESTERN
KANSAS. HOWEVER, A FAIRLY WEAK FLOW ALOFT COMBINED WITH A LACK OF
LOW/MID LEVEL MOISTURE AND LITTLE INSTABILITY PRESENT WILL RESULT
IN GENERALLY DRY CONDITIONS ACROSS WESTERN KANSAS THROUGH THURSDAY
AFTERNOON, ALTHOUGH A FEW SPRINKLES/LIGHT RAIN CANNOT BE RULED OUT
BEHIND THE FRONT WEDNESDAY NIGHT. RIDGING ALOFT IS PROJECTED TO
PUSH ASHORE OFF THE PACIFIC THURSDAY SETTING UP A NORTHWEST FLOW
ALOFT ACROSS THE WESTERN HIGH PLAINS. AN OUTSIDE CHANCE FOR PRECIP
MAY PICK UP A LITTLE THURSDAY NIGHT AS AN H5 VORT MAXIMA TRACKS
SOUTHEAST ACROSS THE NORTHERN PLAINS. HOWEVER, LOW/MID LEVEL
MOISTURE WILL REMAIN MINIMAL AT BEST LIMITING PRECIP CHANCES TO A
FEW ISOLATED SHOWERS WITH THE POTENTIAL FOR A SNOW MIX LATE
THURSDAY NIGHT.
COOLER TEMPERATURES ARE LIKELY WEDNESDAY IN WAKE OF A COLD FRONT
PUSHING SOUTHWARD ACROSS WESTERN KANSAS. COLDER AIR FILTERING DOWN
INTO THE AREA WILL LOWER H85 TEMPERATURES FROM THE TEENS(C) THE DAY
PREVIOUS WELL DOWN INTO THE SINGLE DIGITS(C) BY WEDNESDAY AFTERNOON.
LOOK FOR HIGHS GENERALLY UP INTO THE 60S(F) WITH A FEW UPPER 50S(F)
POSSIBLE NEAR THE I-7O CORRIDOR AND NEAR 70F POSSIBLE IN SOUTH
CENTRAL KANSAS DEPENDING ON THE TIMING OF THE FRONT. EXPECT HIGHS
ONLY UP INTO THE 50S(F) ACROSS CENTRAL KANSAS THURSDAY AS SURFACE
HIGH PRESSURE ACROSS THE NORTHERN PLAINS CONTINUES TO HELP EDGE THE
COOLER AIR MASS FURTHER SOUTHWEST INTO THE HIGH PLAINS. NEAR 60F IS
STILL POSSIBLE IN EXTREME SOUTHWEST KANSAS. SIMILAR HIGH
TEMPERATURES ARE EXPECTED THROUGH THE END OF THE WEEK WITH THE AIR
MASS ACROSS THE HIGH PLAINS UNDERGOING LITTLE CHANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1202 AM CDT TUE MAR 24 2015
OVERNIGHT AS THE FIRST IN A SERIES OF UPPER LEVEL DISTURBANCES
CROSSES INTO CENTRAL KANSAS THE EASTERLY WINDS OVER SOUTHWEST
KANSAS WILL SHIFT TO THE NORTHWEST AND RANGE FROM 10 TO NEAR 15
KNOTS. AS THE WINDS SHIFT TO THE NORTH/NORTHWEST THE 00Z BUFR
SOUNDING DOES INDICATED THE THE MOISTURE NEAR THE SURFACE WILL
INCREASE. THE DEPTH OF THIS MOIST LAYER TOWARDS 12Z TUESDAY IN
HAYS WILL RANGE FROM 3000 TO 4000 FT AGL WHILE AT DDC AND GCK WILL
BE LESS THAN 1500FT AGL. GIVEN THE DEPTH OF THIS MOIST LAYER
BETWEEN 09Z AND 15Z TUESDAY THERE WILL BE A CHANCE FOR LIGHT
PRECIPITATION AS CEILINGS AND VISIBILITIES LOWER INTO THE MVFR/IFR
CATEGORY IN THE HYS AREA. FURTHER SOUTH HRRR AND BUFR SOUNDINGS
INDICATED THE POTENTIAL FOR A BRIEF PERIOD OF MVFR CEILINGS AND
MAINLY IN THE DDC AREA.
AFTER 12Z TUESDAY ANOTHER UPPER LEVEL DISTUBANCE WILL CROSS
WESTERN KANSAS AS AS THIS NEXT SYSTEM PASSES SKIES WILL CLEAR AND
GUSTY NORTHWEST WINDS WILL DEVELOP. ACROSS ALL OF WESTERN KANSAS
THE GUSTY NORTHWEST WINDS WILL RANGE FROM 20 TO NEAR 25 KNOT RANGE
BETWEEN 15Z AND 21Z TUESDAY AND THEN GRADUALLY FALL BACK INTO THE
10 TO 15 KNOT RANGE BY 00Z WEDNESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 39 65 32 58 / 0 10 10 0
GCK 36 64 30 58 / 0 10 10 10
EHA 41 64 34 60 / 0 10 10 10
LBL 38 67 34 60 / 0 10 10 10
HYS 38 62 31 55 / 0 10 10 0
P28 42 68 36 57 / 0 20 20 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 1 PM CDT /NOON MDT/ THIS AFTERNOON TO 7 PM
CDT /6 PM MDT/ THIS EVENING FOR KSZ030-031-043>046-061>066-
074>081-084>090.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...SUGDEN
LONG TERM...JJOHNSON
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
707 PM EDT Tue Mar 24 2015
...Updated Aviation Discussion...
...Forecast Update...
Issued at 601 PM EDT Tue Mar 24 2015
Have updated the grids early this evening to account for ongoing
trends. Convection continues to blossom in two areas early this
evening, one across MO/OK along a synoptic cold front, and another
over portions of southeast MO and southern IL in response to
increasing isentropic ascent and elevated instability atop a cool
airmass in place over the Ohio Valley. There has recently been a
report of dime sized hail with this latter activity across southeast
MO. The latest hi-res guidance shows this main elevated instability
axis remaining mainly off to the west through much of this evening,
so convection should continue to spark over southeast MO and western
KY and weaken as it moves away from the instability over southern IN
and central KY.
However, the latest RAP depicts this elevated instability axis
working into the southern IN and central KY later on this evening
into tonight as the low-level jet veers in response to a PV anomaly
ejecting out of the Central Plains. Therefore, have introduced
thunder into the forecast for late this evening into the overnight
hours, mainly across southern IN and extreme northern KY. Cannot
completely rule out some small hail, but think the more robust
updrafts capable of hail will remain off to the northwest.
Will continue to keep an eye on the second area of convection
currently across MO as it will approach the region toward dawn.
However, with the surface low passing well to the north, the focused
convergence which will be needed to make up for the loss of
instability will be passing to the north as well. Will continue to
keep up with trends this evening as things unfold.
.SHORT TERM (Now through Wednesday Night)...
Issued at 225 PM EDT Tue Mar 24 2015
Surface front is now a very slow-moving warm front draped across
south-central Kentucky. Isentropic lift is triggered an area of
light rain affecting southern Indiana, and just edging into the I-64
corridor in Kentucky. Temps range from the lower/mid 40s along and
north of I-64 to the 60s in south central Kentucky.
Still looking for the front to lift northward overnight. Low-level
jetting will kick up south of the front, with 900 mb winds
increasing to 50-55 kt. Precip chances initially confined to the
north will spread over the entire area as the night progresses, in
response to the front trying to wave back to the south by morning.
Will keep POPs in the chance category and QPF fairly light. Temp
curve is non-diurnal as we expect only a slight drop this evening,
and then rising temps before daybreak as the low-level jet creates
more of a mixy boundary layer.
Even though a surface wave will scoot past to our north Wednesday
morning, the front is oriented parallel to the flow aloft and will
really be left behind. Mid-level subsidence should provide a break
from any precip, so hourly POPs will be slight chance at best for
much of the day. Temps will depend heavily on how much lingering
cloud cover we have, and the current forecast of lower 70s is a
fairly conservative one. Places that get a decent amount of sunshine
could punch well into the 70s Wednesday afternoon.
Another wave will take shape over the southern Plains and lift ENE
through the Ohio Valley Wednesday night. Expect widespread precip
with embedded thunder. Strong mid-level winds through a deep layer
will not need a lot of help to mix down, which supports the marginal
svr wx threat advertised by SPC. The QPF could be fairly substantial
in places, as our current grids show rainfall in excess of 1 inch
during the night over southern Indiana. Short-fuse nuisance flooding
is possible under the heavier pockets of rain.
.LONG TERM (Thursday through Tuesday)...
Issued at 245 PM EDT Tue Mar 24 2015
The focus in the long term is on precipitation/temperature trends
Thursday then the unseasonably cold period Friday into this upcoming
weekend.
The synoptic pattern Thursday morning is expected to feature a
deepening and digging upper level trough through the Upper Midwest
into the Ohio Valley. At the surface, low pressure will likely be
tracking through southern Indiana into central Ohio with warmer,
moist air ahead. Highs Thursday will occur during the morning and
are are likely to be mild, in the mid 50s to low 60s. However, a
very strong cold front will cross through the forecast area over the
course of the day. 24.12z data still shows some minor timing
differences in how quickly the front passes, but overall, a
non-diurnal temperature trend is expected with readings falling into
the 40s by afternoon for much of the area.
Showers and elevated thunderstorms riding on the nose of the 850 mb
moisture transport will likely push across the area early Thursday
morning before moving off into Ohio. That leaves the post-frontal
rain showers and possibly a thunderstorm associated with the upper
level divergence within the right entrance region of the 130 kt jet.
There is some weak MUCAPE noted, on the order of 200-400 J/kg. The
upper level trough axis is expected to pass through Thursday night,
so expecting a quick shut off of precipitation west to east during
the evening. Rainfall amounts Thursday 1/3 to 1/2 of an inch look
reasonable.
Strong Canadian high pressure nosing down out of the northern Plains
will bring an anomalously cold air mass to the Ohio Valley for this
time of the year on Friday. With the deep upper trough overhead,
soundings show favorable, steep low level lapse rates of 7.5 to
8.5C/km with about 150-200mb of saturation. This could be enough to
spark scattered showers across the northern/eastern areas. Thermal
profiles would support a rain/snow/sleet pellet mix at times. Plan
on highs Friday to be stuck in the low to mid 40s with partly to
mostly cloudy skies and brisk northwest winds.
850 mb temps bottom out in the -8 to -11C range Friday night, or
about 3 standard deviations below normal. Not quite record territory
but lows Saturday morning likely to be in the low/mid 20s
regionwide. Would not be surprised if the colder, sheltered locations
fall into the mid/upper teens. Although the growing season hasn`t
fully taken off, those with agricultural interests or sensitive
vegetation should take note for the prolonged hard freezing
temperatures expected.
Below normal temperatures should continue through this upcoming
weekend as 850 mb temperatures climb slowly. The upper level flow
looks to remain northwesterly or zonal at best. A model consensus of
highs in the 40s Saturday then 50s Sunday look reasonable at this
time. 24.12z guidance showing another vigorous shortwave trough
coming down late Sunday or Monday that could reinforce colder
temperatures and bring a chance of precipitation to the area.
&&
.AVIATION (00Z TAF Update)...
Issued at 706 PM EDT Tue Mar 24 2015
Generally VFR conditions are expected through the period. A band of
precipitation continues to push into portions of southern IN and
northern KY, which will likely affect KSDF and KLEX this evening.
May briefly see vsbys drop to high-end MVFR in this activity, but
cigs should remain VFR.
Otherwise, this precipitation will lift northeast later on this
evening, but another line of showers and perhaps even a rumble of
thunder will push in overnight into the pre-dawn hours Wednesday.
The bulk of the precipitation should remain to the north of KSDF and
KLEX, but there may be just enough coverage to include VCSH wording.
High-end MVFR cigs are briefly possible Wednesday morning behind
this activity, before daytime mixing quickly raises bases to VFR.
Otherwise, after the morning precip chance at KSDF and KLEX, the
bulk of the day looks dry before more showers/storms move in
Wednesday night.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........KJD
Short Term.....RAS
Long Term......ZT
Aviation.......KJD
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
603 PM EDT Tue Mar 24 2015
...Forecast Update...
Issued at 601 PM EDT Tue Mar 24 2015
Have updated the grids early this evening to account for ongoing
trends. Convection continues to blossom in two areas early this
evening, one across MO/OK along a synoptic cold front, and another
over portions of southeast MO and southern IL in response to
increasing isentropic ascent and elevated instability atop a cool
airmass in place over the Ohio Valley. There has recently been a
report of dime sized hail with this latter activity across southeast
MO. The latest hi-res guidance shows this main elevated instability
axis remaining mainly off to the west through much of this evening,
so convection should continue to spark over southeast MO and western
KY and weaken as it moves away from the instability over southern IN
and central KY.
However, the latest RAP depicts this elevated instability axis
working into the southern IN and central KY later on this evening
into tonight as the low-level jet veers in response to a PV anomaly
ejecting out of the Central Plains. Therefore, have introduced
thunder into the forecast for late this evening into the overnight
hours, mainly across southern IN and extreme northern KY. Cannot
completely rule out some small hail, but think the more robust
updrafts capable of hail will remain off to the northwest.
Will continue to keep an eye on the second area of convection
currently across MO as it will approach the region toward dawn.
However, with the surface low passing well to the north, the focused
convergence which will be needed to make up for the loss of
instability will be passing to the north as well. Will continue to
keep up with trends this evening as things unfold.
.SHORT TERM (Now through Wednesday Night)...
Issued at 225 PM EDT Tue Mar 24 2015
Surface front is now a very slow-moving warm front draped across
south-central Kentucky. Isentropic lift is triggered an area of
light rain affecting southern Indiana, and just edging into the I-64
corridor in Kentucky. Temps range from the lower/mid 40s along and
north of I-64 to the 60s in south central Kentucky.
Still looking for the front to lift northward overnight. Low-level
jetting will kick up south of the front, with 900 mb winds
increasing to 50-55 kt. Precip chances initially confined to the
north will spread over the entire area as the night progresses, in
response to the front trying to wave back to the south by morning.
Will keep POPs in the chance category and QPF fairly light. Temp
curve is non-diurnal as we expect only a slight drop this evening,
and then rising temps before daybreak as the low-level jet creates
more of a mixy boundary layer.
Even though a surface wave will scoot past to our north Wednesday
morning, the front is oriented parallel to the flow aloft and will
really be left behind. Mid-level subsidence should provide a break
from any precip, so hourly POPs will be slight chance at best for
much of the day. Temps will depend heavily on how much lingering
cloud cover we have, and the current forecast of lower 70s is a
fairly conservative one. Places that get a decent amount of sunshine
could punch well into the 70s Wednesday afternoon.
Another wave will take shape over the southern Plains and lift ENE
through the Ohio Valley Wednesday night. Expect widespread precip
with embedded thunder. Strong mid-level winds through a deep layer
will not need a lot of help to mix down, which supports the marginal
svr wx threat advertised by SPC. The QPF could be fairly substantial
in places, as our current grids show rainfall in excess of 1 inch
during the night over southern Indiana. Short-fuse nuisance flooding
is possible under the heavier pockets of rain.
.LONG TERM (Thursday through Tuesday)...
Issued at 245 PM EDT Tue Mar 24 2015
The focus in the long term is on precipitation/temperature trends
Thursday then the unseasonably cold period Friday into this upcoming
weekend.
The synoptic pattern Thursday morning is expected to feature a
deepening and digging upper level trough through the Upper Midwest
into the Ohio Valley. At the surface, low pressure will likely be
tracking through southern Indiana into central Ohio with warmer,
moist air ahead. Highs Thursday will occur during the morning and
are are likely to be mild, in the mid 50s to low 60s. However, a
very strong cold front will cross through the forecast area over the
course of the day. 24.12z data still shows some minor timing
differences in how quickly the front passes, but overall, a
non-diurnal temperature trend is expected with readings falling into
the 40s by afternoon for much of the area.
Showers and elevated thunderstorms riding on the nose of the 850 mb
moisture transport will likely push across the area early Thursday
morning before moving off into Ohio. That leaves the post-frontal
rain showers and possibly a thunderstorm associated with the upper
level divergence within the right entrance region of the 130 kt jet.
There is some weak MUCAPE noted, on the order of 200-400 J/kg. The
upper level trough axis is expected to pass through Thursday night,
so expecting a quick shut off of precipitation west to east during
the evening. Rainfall amounts Thursday 1/3 to 1/2 of an inch look
reasonable.
Strong Canadian high pressure nosing down out of the northern Plains
will bring an anomalously cold air mass to the Ohio Valley for this
time of the year on Friday. With the deep upper trough overhead,
soundings show favorable, steep low level lapse rates of 7.5 to
8.5C/km with about 150-200mb of saturation. This could be enough to
spark scattered showers across the northern/eastern areas. Thermal
profiles would support a rain/snow/sleet pellet mix at times. Plan
on highs Friday to be stuck in the low to mid 40s with partly to
mostly cloudy skies and brisk northwest winds.
850 mb temps bottom out in the -8 to -11C range Friday night, or
about 3 standard deviations below normal. Not quite record territory
but lows Saturday morning likely to be in the low/mid 20s
regionwide. Would not be surprised if the colder, sheltered locations
fall into the mid/upper teens. Although the growing season hasn`t
fully taken off, those with agricultural interests or sensitive
vegetation should take note for the prolonged hard freezing
temperatures expected.
Below normal temperatures should continue through this upcoming
weekend as 850 mb temperatures climb slowly. The upper level flow
looks to remain northwesterly or zonal at best. A model consensus of
highs in the 40s Saturday then 50s Sunday look reasonable at this
time. 24.12z guidance showing another vigorous shortwave trough
coming down late Sunday or Monday that could reinforce colder
temperatures and bring a chance of precipitation to the area.
&&
.AVIATION (18Z TAF Update)...
Issued at 1250 PM EDT Tue Mar 24 2015
Quasi-stationary front is currently draped just south of BWG, but
VFR conditions prevail across central Kentucky. Spotty precip over
southern Illinois and Indiana, but conditions remain VFR as the
lower ceilings remain well north.
Expect a lowering of ceilings in SDF and LEX this afternoon as the
precip shield edges closer. Could see a lower deck but ceilings
should remain VFR. Any precip will be intermittent and VCSH should
cover it. BWG will remain dry and even a mid-level ceiling looks
like a worst case scenario there.
Front will lift northward overnight, with winds coming around to
southerly by daybreak. Small chances for precip as we get toward
sunrise but probabilities remain too low to mention.
Low-level jetting really cranks up out of the SW once the warm front
is through, but enough of that will mix down that we should see
surface winds pushing 15 kt, and would very likely stay out of any
LLWS mention. Jetting weakens and mixes out, so wind speeds should
stabilize at 10-12 kt for the remainder of the morning. MVFR
ceilings are quite possible but should stay above fuel-alternate.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........KJD
Short Term.....RAS
Long Term......ZT
Aviation.......RAS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
215 PM EDT TUE MAR 24 2015
.UPDATE...
ISSUED AT 215 PM EDT TUE MAR 24 2015
DID AN UPDATE TO THE GRIDS TO FINE TUNE POPS/SKY/WX THROUGH THE
REST OF THE AFTERNOON AND INTO THE EVENING. ALSO TWEAKED THE
MAXT...T...AND TD PER THE LATEST SHORTBLEND GUIDANCE...OBS...AND
TRENDS. THESE UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
UPDATE ISSUED AT 1115 AM EDT TUE MAR 24 2015
14Z SFC ANALYSIS SHOWS A STATIONARY FRONT LYING ACROSS KENTUCKY
AMIDST A TIGHT BAROCLINIC ZONE. AS SUCH...TEMPERATURES VARY WIDELY
ACROSS THE BOUNDARY FROM THE UPPER 30S AND LOWER 40S NORTHWEST TO
THE MID AND UPPER 50S IN THE SOUTHEAST. MID LEVEL CLOUDS HAVE
PUSHED BACK INTO THE AREA ALONG THE FRONT WHILE SOME LIGHT RAIN IN
FOUND THE NORTH OF THE BOUNDARY...GENERALLY ALONG AND NORTH OF
THE OHIO RIVER. DEWPOINTS RANGE FROM THE UPPER 20S IN THE
NORTHEAST PARTS OF THE CWA WHILE LOW 40S ARE FOUND NEAR THE
TENNESSEE BORDER. THE LATEST HRRR AND NAM12 SHOW PATCHES OF LIGHT
RAIN MOVING INTO THE NORTHERN PARTS OF THE AREA DURING THE
AFTERNOON AND INTO THE EVENING. HAVE ADJUSTED THE FORECAST TO
LIMIT ANY PCPN UNTIL AFTER 1 PM AND ALSO TO FINE TUNE SKY COVER
THROUGH THE FIRST PART OF THE EVENING. DID TWEAK THE MAXT...T...
AND TD GRIDS PER THE LATEST SHORTBLEND GUIDANCE...OBS...AND
TRENDS. UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS
WITH A FRESHENED SET OF ZONES TO FOLLOW.
UPDATE ISSUED AT 824 AM EDT TUE MAR 24 2015
FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS AND SKY COVER TO
BETTER JIVE THE LATEST TRENDS IN OBSERVATIONS...OTHERWISE THE
FORECAST REMAINS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 409 AM EDT TUE MAR 24 2015
SURFACE HIGH PRESSURE IS CURRENTLY CENTERED ACROSS SOUTHEAST
CANADA...WITH LOW PRESSURE MOVING FROM THE FRONT RANGE OF THE
ROCKIES INTO THE HIGH PLAINS. A QUASI-STATIONARY FRONT EXTENDS
EAST FROM THE LOW...BECOMING MORE ILL-DEFINED CLOSER TO
TN/KY...ALTHOUGH THE TEMPERATURE GRADIENT IS PRETTY STOUT WITH
30S IN NORTHERN KY/SOUTHERN OH...AND 50S IN TENNESSEE. ALOFT...AN
UPPER LEVEL TROUGH IS MOVING THROUGH THE ROCKIES...WITH RIDGING
ACROSS THE PLAINS.
THE MODELS ARE IN GOOD AGREEMENT THAT A LEAD SHORT WAVE TROUGH
WILL EJECT OUT OF THE ROCKIES TROUGH AND BECOME NEGATIVELY TILTED
AS IT MOVES ACROSS THE PLAINS LATER TODAY...EVENTUALLY MOVING
INTO THE OHIO VALLEY/GREAT LAKES BY WEDNESDAY. THE SURFACE LOW
WILL FOLLOW SUIT...INITIALLY ALLOWING A WARM FRONT TO MOVE NORTH
INTO THE OHIO VALLEY LATER TONIGHT...BEFORE A COLD FRONT QUICKLY
FOLLOWS FOR WEDNESDAY...ALTHOUGH THE SOUTHERN PORTION OF THE FRONT
WILL BE WEAKENING AS THE UPPER LEVEL FORCING SAILS OFF TO THE
NORTH AND EAST.
FOR EASTERN KENTUCKY...TODAY WILL FEATURE QUITE A BIT OF VARIATION
WITH THE HIGH TEMPERATURES...AS LOCATIONS NORTH OF I-64 WILL
REMAIN CLOUDIER AND COOLER WITH READINGS IN THE LOW 50S...WHILE
SOME SUNSHINE AND SOUTHWEST FLOW HELP PUSH HIGHS TO AROUND 70
ALONG AND SOUTH OF THE HAL ROGERS AND HIGHWAY 80 CORRIDORS. A
MODEST LOW LEVEL JET NOSING IN FROM THE WEST WILL ALLOW FOR SOME
SHOWERS TO THREATEN...MAINLY NORTH OF THE MOUNTAIN PARKWAY THIS
AFTERNOON INTO EARLY THIS EVENING. A LULL IN THE POPS WILL OCCUR
LATER THIS EVENING AS THE WARM FRONT LIFTS NORTH...HOWEVER AS THE
COLD FRONT APPROACHES FROM THE WEST OVERNIGHT INTO
WEDNESDAY...POP CHANCES WILL INCREASE ONCE AGAIN...WITH HIGHER
VALUES NORTHWEST...AND LOWER ONES SOUTHEAST. ELEVATED INSTABILITY
OUT AHEAD OF THE COLD FRONT CONTINUES TO BE SHOWN IN THE
MODELS...SO WILL MAINTAIN SLIGHT CHANCES FOR THUNDER.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 431 AM EDT TUE MAR 24 2015
WE BEGIN THE PERIOD WITH FIRST FRONTAL BOUNDARY AND LOW PRESSURE
SYSTEM PUSHING EAST AND NE OF THE REGION. RIGHT NOW THE GFS WANTS
TO KEEP QPF SIGNALS ALONG THE BAROCLINIC ZONE...HOWEVER IT SEEMS
TO BE THE ODD MODEL OUT AT THIS POINT. CONSEQUENTLY LEANED TOWARD
PREVIOUS FORECAST AND MODEL BLENDS FOR THIS PERIOD. THIS KEEPS
SLIGHT POPS IN BETWEEN THESE TWO UPPER LEVEL INDUCED SYSTEMS.
OPTED TO KEEP SLIGHT CHANCE THUNDER GIVEN REASONABLE ELEVATED
INSTABILITY IN PLACE. THE SECOND LOW PRESSURE WILL BEGIN FORMING
ACROSS THE CENTRAL PLAINS WEDNESDAY NIGHT AND WILL BE THE NEXT
MORE SUBSTANTIAL WEATHER MAKER IN THE PERIOD. THIS FEATURE WILL
MOVE NE ALONG THE BAROCLINIC ZONE AS LONG WAVE TROUGH PROGRESSES
EAST. EVENTUALLY SWINGING A STRONG COLD FRONT ACROSS THE REGION
THURSDAY. THIS WILL GIVE BEST CHANCES FOR POPS THROUGH THE PERIOD
WITH THUNDER POSSIBLE ALONG AND NEAR THE FRONT. ONCE AGAIN DECENT
INSTABILITY WITH LAPSE RATES AOA 6.5C PER KM EARLY ON THURSDAY
MAKES THIS SEEM REASONABLE. THINK THE THUNDER WILL DROP OFF
THROUGH THE DAY AS STRONG COLD FRONT WILL USHER IN COLDER AIR
BEHIND IT. THEREFORE DID OPT TO LEAN TOWARD A NON DIURNAL CURVE
THURSDAY WITH TEMPS DROPPING FROM NW TO SE THROUGH THE LATE
AFTERNOON. THIS FRONT WILL PROGRESS EAST THURSDAY NIGHT AND THE
BEST PRECIP CHANCES WILL GO WITH THE FRONT.
SOME QUESTIONS REMAIN FOR FRIDAY ON HOW MUCH MOISTURE WILL BE LEFT
OVER AS ENERGY ASSOCIATED WITH THE UPPER LEVEL TROUGH SWINGS
ACROSS THE OHIO VALLEY. DID LEAN TOWARD THE BLEND WHICH DOES KEEP
SLIGHT TO CHANCE POPS FROM SW TO NE. SOME SLIGHT CHANCE POPS
LINGER INTO FRIDAY NIGHT SUPPORTED BY THE GFS AND GEM. GIVEN THAT
FORECAST SOUNDINGS SUPPORT MIX TO SOME WET FLAKES HAVE
TRANSITIONED TO THIS OVERNIGHT. OTHERWISE IN THE WAKE OF THIS
STRONG COLD FRONT A CANADIAN HIGH IS FORECAST TO DROP SOUTHEAST.
THIS WILL SET THE STAGE FOR CLEARING SKIES AND MUCH COLDER TEMPS
ACROSS EASTERN KENTUCKY MOVING INTO THE WEEKEND. WHILE FRIDAY
NIGHT WILL FEATURE COLD TEMPERATURES WITH LOWS IN THE MID TO UPPER
20S. CLOUDS WILL SLOWLY CLEAR OUT OVERNIGHT AND THE HIGH WILL
STILL BE NOSING INTO THE REGION. SATURDAY WILL FEATURE SUNNY SKIES
AS DRIER AND COOLER AIR CONTINUE TO FILTER INTO THE REGION. BEST
CHANCE FOR RADIATIONAL COOLING AND CLEAR SKIES WILL BE SATURDAY
NIGHT...AS HIGH PRESSURE MOVES RIGHT OVER EASTERN KENTUCKY. THERE
IS STILL A FAIR AMOUNT OF UNCERTAINTY ON SURFACE HIGH
PLACEMENT...AND THESE TEMPS COULD NEED TO BE BUMPED DOWN FROM THE
LOW TO MID 20S THAT ARE IN THE GRIDS DEPENDING ON HOW THIS PLAYS
OUT. THIS AREA OF HIGH PRESSURE WILL SHIFT SE OF THE REGION SUNDAY
LEADING TO RETURN FLOW. HIGH TEMPS WILL BOUNCE BACK INTO THE LOW
TO MID 50S. MODELS BECOME QUITE DIVERGENT BY SUNDAY NIGHT INTO
MONDAY AS ANOTHER UPPER LEVEL WAVE DROPS SOUTHEAST. RIGHT NOW THE
GFS IS MUCH MORE PROGRESSIVE BRINGING A COLD FRONT SOUTH BY SUNDAY
NIGHT...WHILE THE ECMWF BRINGS THIS FEATURE DOWN LATER MONDAY.
STUCK WITH BLEND AT THIS POINT GIVEN THE GREATER UNCERTAINTY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 200 PM EDT TUE MAR 24 2015
VFR CONDITIONS WILL HOLD ON THROUGH MUCH OF THE PERIOD ACROSS THE
FORECAST AREA. A WARM FRONT IS TAKING SHAPE OVER THE NORTHERN
PARTS OF KENTUCKY...ALLOWING FOR SOME SHOWER ACTIVITY AS WELL AS
LOWER CEILINGS...THOUGH STILL VFR. THE BOUNDARY WILL EVENTUALLY
LIFT NORTH OF EASTERN KENTUCKY LATER TONIGHT...BEFORE A COLD FRONT
APPROACHES FROM THE WEST TOWARD DAWN WEDNESDAY MORNING...
THREATENING THE AREA WITH A BAND OF SHOWERS AND PERHAPS A
THUNDERSTORM. LIGHT AND VARIABLE WINDS WILL BECOME OUT OF SOUTH
AT 5 TO 10 KTS BETWEEN 08 AND 14Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GEOGERIAN
LONG TERM...DJ
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1115 AM EDT TUE MAR 24 2015
.UPDATE...
ISSUED AT 1115 AM EDT TUE MAR 24 2015
14Z SFC ANALYSIS SHOWS A STATIONARY FRONT LYING ACROSS KENTUCKY
AMIDST A TIGHT BAROCLINIC ZONE. AS SUCH...TEMPERATURES VARY WIDELY
ACROSS THE BOUNDARY FROM THE UPPER 30S AND LOWER 40S NORTHWEST TO
THE MID AND UPPER 50S IN THE SOUTHEAST. MID LEVEL CLOUDS HAVE
PUSHED BACK INTO THE AREA ALONG THE FRONT WHILE SOME LIGHT RAIN IN
FOUND THE NORTH OF THE BOUNDARY...GENERALLY ALONG AND NORTH OF
THE OHIO RIVER. DEWPOINTS RANGE FROM THE UPPER 20S IN THE
NORTHEAST PARTS OF THE CWA WHILE LOW 40S ARE FOUND NEAR THE
TENNESSEE BORDER. THE LATEST HRRR AND NAM12 SHOW PATCHES OF LIGHT
RAIN MOVING INTO THE NORTHERN PARTS OF THE AREA DURING THE
AFTERNOON AND INTO THE EVENING. HAVE ADJUSTED THE FORECAST TO
LIMIT ANY PCPN UNTIL AFTER 1 PM AND ALSO TO FINE TUNE SKY COVER
THROUGH THE FIRST PART OF THE EVENING. DID TWEAK THE MAXT...T...
AND TD GRIDS PER THE LATEST SHORTBLEND GUIDANCE...OBS...AND
TRENDS. UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS
WITH A FRESHENED SET OF ZONES TO FOLLOW.
UPDATE ISSUED AT 824 AM EDT TUE MAR 24 2015
FRESHENED UP THE HOURLY TEMPERATURES...DEW POINTS AND SKY COVER TO
BETTER JIVE THE LATEST TRENDS IN OBSERVATIONS...OTHERWISE THE
FORECAST REMAINS ON TRACK.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 409 AM EDT TUE MAR 24 2015
SURFACE HIGH PRESSURE IS CURRENTLY CENTERED ACROSS SOUTHEAST
CANADA...WITH LOW PRESSURE MOVING FROM THE FRONT RANGE OF THE
ROCKIES INTO THE HIGH PLAINS. A QUASI-STATIONARY FRONT EXTENDS
EAST FROM THE LOW...BECOMING MORE ILL-DEFINED CLOSER TO
TN/KY...ALTHOUGH THE TEMPERATURE GRADIENT IS PRETTY STOUT WITH
30S IN NORTHERN KY/SOUTHERN OH...AND 50S IN TENNESSEE. ALOFT...AN
UPPER LEVEL TROUGH IS MOVING THROUGH THE ROCKIES...WITH RIDGING
ACROSS THE PLAINS.
THE MODELS ARE IN GOOD AGREEMENT THAT A LEAD SHORT WAVE TROUGH
WILL EJECT OUT OF THE ROCKIES TROUGH AND BECOME NEGATIVELY TILTED
AS IT MOVES ACROSS THE PLAINS LATER TODAY...EVENTUALLY MOVING
INTO THE OHIO VALLEY/GREAT LAKES BY WEDNESDAY. THE SURFACE LOW
WILL FOLLOW SUIT...INITIALLY ALLOWING A WARM FRONT TO MOVE NORTH
INTO THE OHIO VALLEY LATER TONIGHT...BEFORE A COLD FRONT QUICKLY
FOLLOWS FOR WEDNESDAY...ALTHOUGH THE SOUTHERN PORTION OF THE FRONT
WILL BE WEAKENING AS THE UPPER LEVEL FORCING SAILS OFF TO THE
NORTH AND EAST.
FOR EASTERN KENTUCKY...TODAY WILL FEATURE QUITE A BIT OF VARIATION
WITH THE HIGH TEMPERATURES...AS LOCATIONS NORTH OF I-64 WILL
REMAIN CLOUDIER AND COOLER WITH READINGS IN THE LOW 50S...WHILE
SOME SUNSHINE AND SOUTHWEST FLOW HELP PUSH HIGHS TO AROUND 70
ALONG AND SOUTH OF THE HAL ROGERS AND HIGHWAY 80 CORRIDORS. A
MODEST LOW LEVEL JET NOSING IN FROM THE WEST WILL ALLOW FOR SOME
SHOWERS TO THREATEN...MAINLY NORTH OF THE MOUNTAIN PARKWAY THIS
AFTERNOON INTO EARLY THIS EVENING. A LULL IN THE POPS WILL OCCUR
LATER THIS EVENING AS THE WARM FRONT LIFTS NORTH...HOWEVER AS THE
COLD FRONT APPROACHES FROM THE WEST OVERNIGHT INTO
WEDNESDAY...POP CHANCES WILL INCREASE ONCE AGAIN...WITH HIGHER
VALUES NORTHWEST...AND LOWER ONES SOUTHEAST. ELEVATED INSTABILITY
OUT AHEAD OF THE COLD FRONT CONTINUES TO BE SHOWN IN THE
MODELS...SO WILL MAINTAIN SLIGHT CHANCES FOR THUNDER.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 431 AM EDT TUE MAR 24 2015
WE BEGIN THE PERIOD WITH FIRST FRONTAL BOUNDARY AND LOW PRESSURE
SYSTEM PUSHING EAST AND NE OF THE REGION. RIGHT NOW THE GFS WANTS
TO KEEP QPF SIGNALS ALONG THE BAROCLINIC ZONE...HOWEVER IT SEEMS
TO BE THE ODD MODEL OUT AT THIS POINT. CONSEQUENTLY LEANED TOWARD
PREVIOUS FORECAST AND MODEL BLENDS FOR THIS PERIOD. THIS KEEPS
SLIGHT POPS IN BETWEEN THESE TWO UPPER LEVEL INDUCED SYSTEMS.
OPTED TO KEEP SLIGHT CHANCE THUNDER GIVEN REASONABLE ELEVATED
INSTABILITY IN PLACE. THE SECOND LOW PRESSURE WILL BEGIN FORMING
ACROSS THE CENTRAL PLAINS WEDNESDAY NIGHT AND WILL BE THE NEXT
MORE SUBSTANTIAL WEATHER MAKER IN THE PERIOD. THIS FEATURE WILL
MOVE NE ALONG THE BAROCLINIC ZONE AS LONG WAVE TROUGH PROGRESSES
EAST. EVENTUALLY SWINGING A STRONG COLD FRONT ACROSS THE REGION
THURSDAY. THIS WILL GIVE BEST CHANCES FOR POPS THROUGH THE PERIOD
WITH THUNDER POSSIBLE ALONG AND NEAR THE FRONT. ONCE AGAIN DECENT
INSTABILITY WITH LAPSE RATES AOA 6.5C PER KM EARLY ON THURSDAY
MAKES THIS SEEM REASONABLE. THINK THE THUNDER WILL DROP OFF
THROUGH THE DAY AS STRONG COLD FRONT WILL USHER IN COLDER AIR
BEHIND IT. THEREFORE DID OPT TO LEAN TOWARD A NON DIURNAL CURVE
THURSDAY WITH TEMPS DROPPING FROM NW TO SE THROUGH THE LATE
AFTERNOON. THIS FRONT WILL PROGRESS EAST THURSDAY NIGHT AND THE
BEST PRECIP CHANCES WILL GO WITH THE FRONT.
SOME QUESTIONS REMAIN FOR FRIDAY ON HOW MUCH MOISTURE WILL BE LEFT
OVER AS ENERGY ASSOCIATED WITH THE UPPER LEVEL TROUGH SWINGS
ACROSS THE OHIO VALLEY. DID LEAN TOWARD THE BLEND WHICH DOES KEEP
SLIGHT TO CHANCE POPS FROM SW TO NE. SOME SLIGHT CHANCE POPS
LINGER INTO FRIDAY NIGHT SUPPORTED BY THE GFS AND GEM. GIVEN THAT
FORECAST SOUNDINGS SUPPORT MIX TO SOME WET FLAKES HAVE
TRANSITIONED TO THIS OVERNIGHT. OTHERWISE IN THE WAKE OF THIS
STRONG COLD FRONT A CANADIAN HIGH IS FORECAST TO DROP SOUTHEAST.
THIS WILL SET THE STAGE FOR CLEARING SKIES AND MUCH COLDER TEMPS
ACROSS EASTERN KENTUCKY MOVING INTO THE WEEKEND. WHILE FRIDAY
NIGHT WILL FEATURE COLD TEMPERATURES WITH LOWS IN THE MID TO UPPER
20S. CLOUDS WILL SLOWLY CLEAR OUT OVERNIGHT AND THE HIGH WILL
STILL BE NOSING INTO THE REGION. SATURDAY WILL FEATURE SUNNY SKIES
AS DRIER AND COOLER AIR CONTINUE TO FILTER INTO THE REGION. BEST
CHANCE FOR RADIATIONAL COOLING AND CLEAR SKIES WILL BE SATURDAY
NIGHT...AS HIGH PRESSURE MOVES RIGHT OVER EASTERN KENTUCKY. THERE
IS STILL A FAIR AMOUNT OF UNCERTAINTY ON SURFACE HIGH
PLACEMENT...AND THESE TEMPS COULD NEED TO BE BUMPED DOWN FROM THE
LOW TO MID 20S THAT ARE IN THE GRIDS DEPENDING ON HOW THIS PLAYS
OUT. THIS AREA OF HIGH PRESSURE WILL SHIFT SE OF THE REGION SUNDAY
LEADING TO RETURN FLOW. HIGH TEMPS WILL BOUNCE BACK INTO THE LOW
TO MID 50S. MODELS BECOME QUITE DIVERGENT BY SUNDAY NIGHT INTO
MONDAY AS ANOTHER UPPER LEVEL WAVE DROPS SOUTHEAST. RIGHT NOW THE
GFS IS MUCH MORE PROGRESSIVE BRINGING A COLD FRONT SOUTH BY SUNDAY
NIGHT...WHILE THE ECMWF BRINGS THIS FEATURE DOWN LATER MONDAY.
STUCK WITH BLEND AT THIS POINT GIVEN THE GREATER UNCERTAINTY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 824 AM EDT TUE MAR 24 2015
EXPECT VFR CONDITIONS TO HOLD ON THROUGH THE PERIOD ACROSS THE
AREA. A WEAK WARM FRONT WILL THEN DEVELOP DURING THE
DAY...ALLOWING FOR SOME SHOWER ACTIVITY AS WELL AS LOWER
CEILINGS...ALTHOUGH STILL VFR. THE BOUNDARY WILL EVENTUALLY LIFT
NORTH OF EASTERN KENTUCKY LATER TONIGHT...BEFORE A COLD FRONT
APPROACHES FROM THE WEST TOWARD DAWN WEDNESDAY MORNING...
THREATENING MAINLY THE I-64 CORRIDOR WITH SHOWERS AND PERHAPS A
RUMBLE OF THUNDER. WINDS WILL BE OUT OF THE ENE AT 5 TO 10 KTS
INITIALLY AND THEN LIGHTEN UP TOWARDS DUSK. WINDS WILL THEN BECOME
OUT OF SOUTH AT 5 TO 10 KTS BETWEEN 08 AND 12Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GEOGERIAN
LONG TERM...DJ
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
254 PM CDT TUE MAR 24 2015
.DISCUSSION...
DESPITE THE LEAD SHORTWAVE EJECTING OUT OF THE INTER MOUNTAIN
WEST INTO THE CENTRAL PLAINS...WELL NORTH OF OUR REGION...THERE IS
ENOUGH OF A WEAKNESS WITH THE TROUGH ACROSS THE SOUTHERN PLAINS
THAT WE ARE CLOSELY MONITORING POSSIBLE DEVELOPMENT OF SHOWERS AND
THUNDERSTORMS ACROSS EASTERN OKLAHOMA INTO WESTERN ARKANSAS THIS
AFTERNOON/EVENING.
VIS SATELLITE SHOWING A WELL DEFINED CU FIELD ACROSS N CENTRAL TX
INTO EASTERN OK/NW AR AHEAD OF A STRONG COLD FRONT WHICH AS OF 19Z
WAS LOCATED NEAR A BVO...SPS...ABI LINE. THIS FRONT WILL CONTINUE
TO SLOW AND WILL EVENTUALLY STALL JUST NORTHWEST OF OUR REGION
LATER THIS EVENING. MESOANALYSIS ACROSS THE SOUTHERN PLAINS IS
SHOWING CAPE VALUES NEAR 1000-1500 J/KG POOLING JUST AHEAD OF THE
FRONTAL BOUNDARY WITH LITTLE CINH REMAINING. DEEP LAYER SHEAR IS
ON THE ORDER OF MAGNITUDE OF 40-50KTS WITH MID LEVEL LAPSE RATES
AT OR NEAR 8 DEG/KM. LATEST RUNS OF THE HRRR AND NAM OUTPUT
SUGGESTS CONVECTION WILL LIKELY INITIATE BETWEEN 20-22Z ACROSS SW
MO...SE KS...NE OK...WITH THE CONVECTION BUILDING SOUTH AND WEST
ALONG THE COLD FRONT INTO SE OK. MCCURTAIN COUNTY MAY BE ON THE
SOUTHERN END OF ANY CONVECTION THAT CAN DEVELOP SOUTHWARD ALONG
THE BOUNDARY LATER THIS EVENING. SWOMCD IS CURRENTLY OUT FOR OUR
EXTREME NW ZONES AND A SEVERE THUNDERSTORM WATCH COULD BE ISSUED
FOR A FEW OF OUR NW COUNTIES LATER THIS AFTERNOON. CONVECTION
SHOULD WEAKEN QUICKLY AFTER MIDNIGHT IN COVERAGE AND INTENSITY
WITH STABILIZING EFFECTS OF THE BOUNDARY LAYER.
LOOKING AT A REPEAT SCENARIO FOR WEDNESDAY...EXCEPT ACROSS A
LARGER REGION OF THE SOUTHERN PLAINS BUT AGAIN...OUR REGION WILL
BE RIGHT ON THE EDGE OF STRONG TO SEVERE THUNDERSTORMS...MAINLY
ALONG AND NORTHWEST OF THE I-30 CORRIDOR WEDNESDAY EVENING. A
REINFORCING COLD FRONT ASSOCIATED WITH A LONGWAVE TROUGH WILL
EJECT OUT OF THE INTER MOUNTAIN WEST AND INTO THE PLAINS WED
NIGHT. THIS FRONT LOOKS TO PUSH COMPLETELY THROUGH OUR REGION LATE
WED NIGHT/THU TIME PERIOD BUT MUCH LIKE TONIGHT`S CONVECTION...WE
QUICKLY STABILIZE WED EVENING AS THE FRONT NEARS OUR REGION.
CANNOT RULE OUT SOME ISOLATED STRONG TO SEVERE THUNDERSTORMS
ACROSS OUR NW ZONES INITIALLY BUT AGREE WITH SPC`S DAYTWO OUTLOOK
KEEPING MORE WIDESPREAD ACTIVITY NORTH AND WEST OF OUR REGION
DUE TO STABILIZING EFFECTS AFTER SUNSET WED EVENING.
FRONT PUSHES SOUTHEAST OF OUR REGION QUICKLY ON THURSDAY TAKING
THE RAIN WITH IT. AMOUNTS LOOKING GENERALLY AROUND ONE QUARTER TO
ONE HALF INCH WITH THE EVENT...THUS SHOULD NOT RESULT IN MUCH IF
ANY IMPLICATIONS ON AREA RIVERS AND LAKES WHICH REMAIN HIGH ATTM.
IN THE WAKE OF THE TROUGH WED/THU...EXPANSIVE UPPER RIDGING WILL
DOMINATE THE WESTERN THIRD OF THE COUNTRY WITH A DRY NORTHWEST
FLOW COMMENCING FOR OUR REGION. MODELS CONTINUE TO WARM
TEMPERATURES FOR THE WEEKEND SO FOLLOWED THEIR LEAD CLOSELY. THE
RIDGE OUT WEST BEGINS TO BREAK DOWN EARLY NEXT WEEK AND WILL NEED
TO BE WATCHED FOR INCREASING MOISTURE AND RAIN CHANCES BY THE
EARLY TO MIDDLE PORTION OF NEXT WEEK.
PRELIMS TO FOLLOW...13.
&&
.PREV DISCUSSION... /ISSUED 108 PM CDT TUE MAR 24 2015/
AVIATION...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH MUCH OF THE 18Z TAF
PD. MVFR STRATUS AND SOME PATCHY BR IS EXPECTED AT MOST SITES
BY 07Z-09Z...AND IS EXPECTED TO LIFT/SCATTER BY THE END OF THE PD.
OTHERWISE...EXPECT SOUTHERLY WINDS 8-12 KTS WITH HIGHER GUSTS
THROUGH THE AFTERNOON...DECREASING TO BETWEEN 5 AND 10 KTS
OVERNIGHT. /12/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 59 82 57 63 / 10 10 50 40
MLU 54 80 59 64 / 10 10 20 50
DEQ 56 79 49 62 / 40 20 70 30
TXK 59 80 53 62 / 20 20 60 30
ELD 56 78 57 63 / 20 10 50 50
TYR 60 81 53 62 / 10 10 60 30
GGG 59 82 55 63 / 10 10 60 30
LFK 59 84 58 66 / 10 10 30 40
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
12/13
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
928 PM EDT WED MAR 25 2015
.SYNOPSIS...
SHOWERS ARE EXPECTED THURSDAY AS LOW PRESSURE CROSSES THE UPPER
OHIO VALLEY REGION. MUCH COLDER WEATHER WILL FOLLOW THROUGH THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
DRY WEATHER IS EXPECTED TO CONTINUE TONIGHT UNTIL DEVELOPING LOW
PRESSURE BEGINS TO ADVANCE ACROSS THE OHIO VALLEY REGION
LATE...RETURNING SHOWER CHANCES TO THE REGION. FURTHER ADJUSTED
SKY COVER TONIGHT BASED ON SATELLITE...SURFACE OBS AND NEAR TERM
MODELS. NUDGED TEMPERATURES TO THE LATEST LAMP AND HRRR NUMBERS...
WHICH CAME IN 10 TO 15 DEGREES ABOVE AVERAGE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
COLD FRONT STARTS NEAR OR JUST INTO NW CORNER OF CWA AT 12Z
THURSDAY. WAVE ALONG THE BOUNDARY WILL KEEP EASTWARD PROGRESS SLOW
DURING THE DAY...BUT MODELS ARE IN GOOD AGREEMENT IN HAVING IT
EAST OF THE AREA BY SUNSET. BEST QPF WILL LIE CLOSE TO THE TRACK
OF THE SURFACE LOW IN OHIO. HOWEVER...ENTIRE CWA IS EXPECTED TO
GET A GOOD SOAKING. PWATS WILL BE PUNCHING UP NEAR OR JUST OVER
1.0 INCH IN DECENT SW FLOW AHEAD OF FRONT. LIFT WILL BE AIDED BY A
TIGHTENING TEMPERATURE GRADIENT ALONG THE FRONT ALONG WITH STRONG
LOW LEVEL CONVERGENCE. TOTAL QPF OF 0.4" TO 0.8" LOOKS GOOD FOR
THIS EVENT. THERE MAY BE ENOUGH INSTABILITY TO PRODUCE AN ISOLATED
THUNDERSTORM EAST OF A LBE-MGW LINE. CATEGORICAL POPS ARE
APPROPRIATE AREA WIDE. EXPECTING A NON-DIURNAL TEMPERATURE TRACE
ESPECIALLY IN THE WEST...WITH MUCH ABOVE NORMAL TEMPERATURES
ESPECIALLY IN THE SOUTHEAST COUNTIES.
PRECIP COVERAGE WILL DECREASE THROUGH THE NIGHT AS THE COLDER AIR
RUSHES IN BEHIND THE FRONT. CHANGEOVER TO SNOW WILL PROGRESS FROM
NORTHWEST TO SOUTHEAST WITH TIME AS SUBZERO 850 MB AIR LAGS THE
FRONT A BIT. GIVEN THE TIME OF YEAR AND RELATIVELY WARM
GROUND...NOT EXPECTING MUCH SNOW ACCUMULATION.
EXPECTING SCATTERED SHOWERS TO REDEVELOP FRIDAY AS AN UPPER SHORTWAVE
TROUGH ROTATES SOUTHEAST ACROSS THE GREAT LAKES. MOISTURE IS
LIMITED...SO QPF IS LOW. DURING THE DAY...A WARM BOUNDARY LAYER
WILL ALLOW FOR A MIX OR CHANGEOVER TO RAIN IN MANY AREAS.
PRECIPITATION WILL CHANGE BACK TO SNOW FRIDAY NIGHT. EXPECTING
SHSN TO TAPER OFF BY MIDDAY SATURDAY AS H850 THERMAL TROUGH BEGINS
TO LIFT OUT. TEMPERATURES WILL REMAIN WELL BELOW NORMAL FRIDAY
THROUGH SATURDAY. ONLY MINOR MODIFICATIONS TO PREVIOUS TEMPERATURE
FORECAST.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE IS EXPECTED TO TAKE CONTROL OVER THE WEEKEND. ANOTHER
SYSTEM EMBEDDED IN NW FLOW ALOFT IS PROGGED TO APPROACH THE AREA
BY EARLY NEXT WEEK. TEMPERATURES ARE EXPECTED TO REMAIN BELOW
SEASONAL LEVELS.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
CONDITION DETERIORATION IS EXPECTED TONIGHT WITH THE ADVANCE OF LOW
PRESSURE. MVFR CEILING DEVELOPMENT WILL DEGRADE TO IFR IN SHOWERS
DURING THE PREDAWN HOURS. IMPROVEMENT IS NOT ANTICIPATED UNTIL
AFTER THE COLD FRONT PASSAGE ON THURSDAY AFTERNOON.
.OUTLOOK.../THURSDAY NIGHT THROUGH MONDAY/...
RESTRICTIONS ARE POSSIBLE INTO SATURDAY AS COLD ADVECTION CONTINUES
IN THE WAKE OF THE FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
428 PM EDT TUE MAR 24 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 427 PM EDT TUE MAR 24 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A COMPLEX OF SHORTWAVE
ENERGY FROM THE PACIFIC NW/NRN ROCKIES INTO THE PLAINS STATES. LEAD
ENERGY RESULTED IN CONVECTION ACROSS SRN MO/SRN IL TODAY. CLOSER TO
HOME...SHORTWAVE RIDGE OVER THE UPPER GREAT LAKES HAS ALLOWED SFC
HIGH PRES TO DOMINATE THE REGION TODAY. DRY AIR MASS/SUBSIDENCE
ASSOC WITH THE RIDGE HAS RESULTED SUNNY SKIES ACROSS THE UPPER LAKES
TODAY. WITH THE CENTER OF THE SFC HIGH WELL TO THE EAST...SSE WINDS
OFF LAKE MI HAVE RESULTED IN COOLER TEMPS (MAINLY IN THE 30S) OVER
THE EAST HALF OF THE CWA WHILE THE WARMEST TEMPS HAVE BEEN OVER THE
FAR WEST WHERE READINGS HAVE MANAGED TO REACH INTO THE MID TO UPPER
40S.
TONIGHT AND WEDNESDAY...ATTENTION TURNS TO THE MULTIPLE SHORTWAVES
CURRENTLY MOVING ACROSS THE PACIFIC NW AND WRN PLAINS. 12Z MODELS
STILL INDICATE LEAD ENERGY MOVING OUT ACROSS NE/KS THIS AFTN TAKING
ON A NEGATIVE TILT AS IT MOVES TO VCNTY OF SRN LAKE MI BY 12Z WED
WHILE ANOTHER SHORTWAVE MOVES ACROSS THE DAKOTAS INTO MN. THIS WILL
LEAD TO 2 SFC LOW CENTERS AT 12Z WED...ONE OVER NW MN AND THE SECOND
IN THE VCNTY OF SRN LAKE MI. FOR THE FCST AREA...THIS SHOULD
GENERALLY MEAN THAT THE HEAVIEST PCPN WOULD PASS BY TO THE SE OF
HERE...AND PCPN SHOULD FALL ALMOST EXCLUSIVELY AS SNOW AS IT ARRIVES
FROM THE S AND SW LATE TONIGHT. THERE IS STILL JUST ENOUGH
UNCERTAINTY IN THERMAL PROFILES (PARTICULARLY THE NAM...WHICH SHOWS
A FARTHER NORTH PLACEMENT OF SECONDARY SFC LOW THAN REST OF MODELS)
TO INCLUDE A MENTION OF -FZRA CLOSE TO LAKE MI AND FAR ERN PORTION
OF CWA AS ABOVE FREEZING TEMPS ALOFT COULD BRIEFLY NOSE INTO THE
AREA.
WILL CONTINUE TO UTILIZE MOSTLY A CONSENSUS APPROACH OF ALL AVBL
GUIDANCE TO CONSTRUCT POPS/QPF TONIGHT INTO WED. RESULT IS PCPN
SPREADING N AND NE INTO THE FCST AREA AFTER 06Z. IT`S POSSIBLE THE
SNOW MAY NOT ARRIVE OVER THE FAR N AND E FCST AREA UNTIL 12Z WED OR
AFTER. SHOULD BE LOOKING AT QPF RANGES FROM LESS THAN 0.10 INCH
NORTH TO 0.25 INCHES OVER SRN MNM COUNTY BY 12Z. AS NEG-TILT
SHORTWAVE CONTINUES TO LIFT NE ON WEDNESDAY...MODELS SHOW HEAVIEST
PCPN WILL LIFT INTO ERN COUNTIES OF THE CWA. MOST OF THE MODELS
PARTICUALRLY THE NAM AND REG-GEM SHOW A SECONDARY MAX OF PCPN OVER
NW MQT COUNTY AND THE HURON MOUNTAINS AREA LATE TONIGHT/WED MORNING
IN RESPONSE TO REGION OF ENHANCED MID-LVL FGEN/DEFORMATION SO HAVE
ALSO BUMPED UP QPF AMOUNTS OVER THIS AREA AS WELL. LOOKING AT TOTAL
QPF THROUGH THE EVENT...AMOUNTS GENERALLY RANGE FROM .30 INCH OR
MORE ALONG AND EAST OF A LINE FROM BIG BAY TO IRON MOUNTAIN...WITH
.25 INCH OR LESS WEST OF THIS LINE. VIGOROUS DYNAMICS AND HEALTHY
ISENTROPIC ASCENT NOTED ON 290K SFC SHOULD LEAD TO DECENT PCPN RATES
DURING PEAK FORCING WHICH REACHES THE WI BORDER IN THE 09Z-12Z TIME
FRAME. ALTHOUGH MIXING RATIOS OF 3-4G/KG ARE AVBL AROUND
750MB...SHORT DURATION OF STRONG FORCING (3-6 HRS) AND LOWER SNOW TO
WATER RATIOS DOWN TO AROUND 10 TO 1 MAKE FOR LOWER CONFIDENCE ON
SNOW ACCUMULATIONS REACHING ADVY LEVEL. QPF AMOUNTS COMBINED WITH
SLR OF 10:1 RESULTED IN MOST OF CENTRAL AND ERN CWA STAYING BTWN 2.5
TO 3 INCHES OF SNOW. SINCE SNOW AMOUNTS SHOULD STAY JUST BLO
ADVISORY FOR MUCH OF THE CENTRAL AND ERN CWA WILL JUST CONTINUE THE
SPS AND EXPAND TO INCLUDE MQT-BARAGA AND DICKINSON COUNTIES. WL
CONTINUE TO HIGHLIGHT POTENTIAL FOR MODERATE SNOW AND
SLUSHY/SLIPPERY ROADS DURING THE MORNING COMMUTE IN SPS.
SNOW WILL TAPER OFF QUICKLY FM WEST LATE MORNING/EARLY AFTERNOON AS
NEG-TILT SHORTWAVE QUICKLY MOVES EAST ALLOWIN FOR DRY SLOT TO MOVE
INTO UPPER MI. SOME WRAP AROUND MOISTURE ON BACKSIDE OF LOW COULD
ALLOW FOR LIGHT SNOW TO LINGER INTO THE AFTERNOON HRS OVER THE NW
CWA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 339 PM EDT TUE MAR 24 2015
THE FIRST WAVE OF PRECIPITATION WILL HAVE QUICKLY SHIFTED NORTHEAST
OF THE AREA ON WEDNESDAY...LEAVING THE TRAILING SHORTWAVE AND
SURFACE TROUGH STRETCHING SOUTHWEST ACROSS NORTHERN/WESTERN LAKE
SUPERIOR AT 00Z THURSDAY. EXPECT THERE TO BE SOME RAIN/SNOW SHOWERS
OCCURRING ALONG THIS TROUGH (WETBULB ZERO HEIGHTS SUPPORT A MIX
INITIALLY)...LARGELY OVER WESTERN LAKE SUPERIOR AND OVER THE
KEWEENAW. THE SURFACE-850MB TROUGH WILL THEN SLOWLY SINK SOUTHEAST
ACROSS UPPER MICHIGAN WEDNESDAY NIGHT...LEADING TO MUCH COLDER AIR
TO MOVE INTO THE AREA UNDER NORTHERLY FLOW. 850MB TEMPS WILL DROP
FROM -6C AT 00Z THURSDAY TO -11C BY 12Z AND -17C BY 00Z FRIDAY. THIS
COLDER AIR WILL LEAD TO ENHANCEMENT OF THE SNOW INITIALLY...BEFORE
TRANSITIONING TO PURE LAKE EFFECT DURING THE DAY ON THURSDAY AS THE
DEEPER MOISTURE DEPARTS. THE LOW LEVEL WINDS WILL BE VEERING THROUGH
THE WEDNESDAY NIGHT PERIOD (WESTERLY AT 00Z THURSDAY AND N-NNW BY
12Z THURSDAY)...LIMITING THE FOCUS OF THE TERRAIN ENHANCEMENT
INITIALLY WEDNESDAY EVENING. AS WINDS PERSIST OUT OF THE NORTHERLY
DIRECTION THROUGH THE DAY ON THURSDAY...THE TERRAIN ENHANCEMENT WILL
BECOME FOCUSED AND HAVE THE HIGHEST POPS IN THE NORTHERLY WIND
UPSLOPE AREAS DOWNWIND OF THE OPEN WATER ON LAKE SUPERIOR
(ESSENTIALLY AROUND GOGEBIC/ONTONAGON/MARQUETTE COUNTIES). WHILE
THIS WILL LEAD TO A FAVORABLE PERIOD OF LAKE ENHANCED AND UPSLOPE
SNOW WEDNESDAY NIGHT INTO THURSDAY MORNING...THE SNOW AMOUNTS WILL
DEPEND ON HOW QUICKLY WINDS VEER ON WEDNESDAY NIGHT. WILL FOLLOW THE
GENERAL CONSENSUS ON THE TIMING...WITH THE BEST LAKE ENHANCED QPF
OVER THE KEWEENAW IN THE EVENING AND SPREADING SOUTH TO
GOGEBIC/ONTONAGON/MARQUETTE/BARAGA COUNTIES DURING THE OVERNIGHT
HOURS. SNOW RATIOS WILL START UP AT OR BELOW 10-1 BEFORE TRENDING UP
DURING THE OVERNIGHT HOURS INTO THURSDAY AS THE COLD AIR SURGES INTO
THE AREA AND PUTS THE FOCUS OF THE FORCING CLOSER TO THE DGZ. ALL IN
ALL...HAVE SNOWFALL AMOUNTS WEDNESDAY NIGHT INTO THURSDAY OVER THOSE
PREVIOUSLY MENTIONED FAVORED AREAS OF 3 TO 6 INCHES (AND
POTENTIALLY UP TO 7 INCHES OVER THE PORKIES). IN ADDITION TO THE
SNOW...THE NORTHERLY WINDS WILL BE FAIRLY GUSTY ON THURSDAY
(25-30KTS AND SOME GALE FORCE GUSTS OVER CENTRAL LAKE
SUPERIOR)...WHICH WITH THE FLUFFIER NATURE OF THE SNOW BY THAT TIME
WILL LIKELY LEAD TO SOME BLOWING SNOW ALONG THE LAKE SUPERIOR
SHORELINES.
AS DRY AIR FROM THE CANADIAN HIGH PRESSURE IN MANITOBA NOSES INTO
WESTERN LAKE SUPERIOR ON THURSDAY AFTERNOON...EXPECT THE LAKE
EFFECT TO BEGIN TO DIMINISH AND WILL START LOWERING POPS DURING THE
AFTERNOON AND CONTINUE THE TREND INTO THURSDAY NIGHT. THERE DOES
APPEAR TO BE A FAVORABLE PERIOD OF THE CLOUD BEING WITHIN THE DGZ
LATE THURSDAY AFTERNOON INTO THURSDAY EVENING...WHICH WILL ATTEMPT
TO OFFSET THE DRIER AIR AND LOWERING INVERSION HEIGHTS...BUT DON/T
EXPECT THE ACCUMULATION TO BE TOO SIGNIFICANT (ADDITIONAL AMOUNTS
AROUND 1 INCH ON THURSDAY NIGHT).
AS THE HIGH CONTINUES SOUTH THROUGH MINNESOTA LATE THURSDAY NIGHT
AND INTO WISCONSIN FRIDAY AFTERNOON...A RIDGE WILL SLIDE ACROSS THE
UPPER GREAT LAKES REGION AND BRING AN END TO ANY LINGERING LAKE
EFFECT FRIDAY MORNING. DRY CONDITIONS WILL PERSIST THROUGH FRIDAY
NIGHT AND SATURDAY...AS THE RIDGE LINGERS OVER THE AREA AS THE HIGH
MOVES INTO THE SOUTHEAST CONUS. AFTER BELOW NORMAL TEMPERATURES ON
THURSDAY AND FRIDAY...SATURDAY/S TEMPERATURES WILL REBOUND TOWARDS
NORMAL.
FOCUS THEN TURNS TO A SHORTWAVE COMING ON SHORE IN THE PACIFIC
NORTHWEST FRIDAY NIGHT. THIS WAVE WILL MOVE EAST OVER THE CANADIAN
ROCKIES AND THEN EITHER THROUGH ONTARIO OR THE UPPER GREAT LAKES
REGION LATE SATURDAY NIGHT AND SUNDAY MORNING. OVERALL...MODELS
HAVE BEEN CONSISTENT ON THE TIMING OF THIS FEATURE...THEY JUST VARY
ON THE STRENGTH OF THE UPPER RIDGE OVER THE CENTRAL/SOUTHERN
ROCKIES. THE STRENGTH OF THAT RIDGE WILL DETERMINE IF THE WAVE
DIVES FARTHER SOUTH AND THROUGH THE REGION OR STAYS TO THE NORTH.
FEEL CONFIDENT ON THE TIMING TO SHOW MORE DETAIL IN THAT PORTION OF
THE FORECAST...BUT WILL KEEP POPS STILL IN THE HIGH CHANCE
CATEGORY. WILL KEEP PCPN IN THE FORECAST INTO SUNDAY AND EVEN
SUNDAY NIGHT...AS THERE ARE HINTS OF A SECONDARY WAVE SWEEPING
THROUGH THE AREA. THE PRECIP TYPE STILL IS A LITTLE UNCERTAIN...BUT
THE INITIAL WAVE SHOULD FALL AS SNOW AND THEN MIX WITH OR TURN TO
RAIN ON THE BACK SIDE. THAT POTENTIAL FOR RAIN WILL CONTINUE INTO
SUNDAY...BEFORE COLDER AIR MOVES BACK INTO THE REGION AND SWITCHES
ANY REMAINING PRECIPITATION BACK TO SNOW SUNDAY NIGHT.
THOSE SHORTWAVES WILL SHIFT EAST OF THE AREA SUNDAY NIGHT AND ALLOW
AN UPPER RIDGE TO NOSE EAST INTO THE UPPER GREAT LAKES REGION ON
MONDAY BEFORE FLATTENING ON TUESDAY. THIS WILL ALLOW FOR WARMER
AIR ALOFT TO WORK INTO THE AREA STARTING ON MONDAY AND ESPECIALLY
ON TUESDAY (925MB TEMPS RISING TO AT LEAST 6C). THAT SHOULD PUSH
HIGHS TO OR ABOVE 50 DEGREES FOR MUCH OF THE CWA FOR THE LAST DAY
OF MARCH (NORMAL IS 40-45). LOOKING FARTHER AHEAD...THE PATTERN
LOOKS TO TURN A LITTLE MORE ACTIVE FOR THE SECOND HALF OF NEXT
WEEK...AS THE MODELS REMAIN CONSISTENT ON A STRONGER WAVE MOVE EAST
TOWARDS THE GREAT LAKES REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 151 PM EDT TUE MAR 24 2015
VERY DRY AIR IN THE LOW TO MID LEVELS ASSOCIATED WITH HIGH PRES
MOVING E ACROSS THE LOWER GREAT LAKES TODAY WILL ENSURE VFR
CONDITIONS AT KIWD/KCMX/KSAW THROUGH THIS EVENING. LOW PRES LIFTING
NE TOWARD LAKE MICHIGAN TONIGHT WILL SPREAD SNOW INTO UPPER MI LATE
TONIGHT INTO WED MORNING. IFR CONDITIONS SHOULD REACH KIWD BY 10Z AND
KCMX BY 14Z AND THEN IMPROVE BACK UP TO MVFR BY LATE WED
MORNING/EARLY AFTERNOON. KSAW HAS BEST POTENTIAL FOR HEAVIER SNOW
CLOSER TO TRACK OF SFC LOW SO EXPECT CONDITIONS THERE TO LOWER TO
LIFR SHORTLY AFT 12Z AND THEN IMPROVE BACK TO MVFR BY 16Z AS SYSTEM
LIFTS QUICKLY E.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 PM EDT TUE MAR 24 2015
WINDS WILL REMAIN MOSTLY UNDER 20 KT TONIGHT INTO WED AS LOW PRES
TROF SETS UP ACROSS THE LAKE BTWN ONE LOW PRES CENTER MOVING E
TOWARD LAKE SUPERIOR AND THE OTHER LIFTING NE THRU LWR MI INTO
ONTARIO. THE TROF WILL DROP S OF THE LAKE WED NIGHT...AND WINDS WILL
THEN INCREASE INTO THU AS HIGH PRES BUILDS S TOWARD THE NRN PLAINS
AND MUCH COLDER AIR SPREADS SE INTO THE UPPER LAKES. NORTHERLY WINDS
SHOULD INCREASE TO 20-30KT LATE WED NIGHT INTO THU...AND IT`S NOT
OUT OF THE QUESTION THAT GALE FORCE GUSTS COULD OCCUR FOR A TIME
OVER CNTRL PORTIONS OF LAKE SUPERIOR. WINDS WILL THEN DIMINISH FRI
AS THE HIGH PRES ARRIVES OVER THE WRN GREAT LAKES. SW WINDS TO 25 KT
WILL BEGIN TO RAMP UP AGAIN LATE SAT INTO SUN MORNING AS THE HIGH
SHIFTS TO THE OHIO VALLEY AND LOW PRES DROPS SE FM MANITOBA TOWARD
THE UPPER GREAT LAKES. WINDS TO 25 KT WL SHIFT W-NW SUN AFTERNOON
BEHIND TROF PASSAGE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
339 PM EDT TUE MAR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 557 AM EDT TUE MAR 24 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A MESSY COMPLEX OF
SHORTWAVE ENERGY MOVING ACROSS THE PACIFIC NW AND ROCKIES. LEAD
ENERGY IS ALREADY GENERATING SHRA/TSRA ACROSS THE CNTRL PLAINS EARLY
THIS MORNING. CLOSER TO HOME...SHORTWAVE RIDGE OVER MN IS SUPPORTING
SFC HIGH PRES OVER THE GREAT LAKES. ASSOCIATED DRY AIR
MASS/SUBSIDENCE AHEAD OF RIDGE IS RESULTING IN CLEAR SKIES ACROSS
THE UPPER LAKES EARLY THIS MORNING. WITH LIGHT/CALM WIND...TEMPS IN
THE INTERIOR E HALF HAVE FALLEN INTO THE LOWER TEENS AND SINGLE
DIGITS WITH A FEW SPOTS RECENTLY NEAR 0F. OUT W...20S ARE MORE
COMMON WITH A LIGHT S WIND STIRRING.
MID/UPPER RIDGE SHIFTING ACROSS THE WRN GREAT LAKES TODAY ALONG WITH
DRY AIR MASS WILL RESULT IN ABUNDANT SUNSHINE. HIGH WILL REACH THE
40S OVER THE MUCH OF THE W HALF. S TO SE WINDS OFF LAKE MI WILL KEEP
THE E HALF COOLER IN THE 30S...PROBABLY LOW 30S NEAR THE SHORE OF
LAKE MI.
TONIGHT...ATTENTION TURNS TO THE MULTIPLE SHORTWAVES CURRENTLY
MOVING ACROSS THE PACIFIC NW AND ROCKIES. LEAD ENERGY MOVING OUT
ACROSS NE/KS THIS AFTN IS STILL FCST TO TAKE ON A NEGATIVE TILT AS
IT MOVES TO VCNTY OF SRN LAKE MI BY 12Z WED WHILE ANOTHER SHORTWAVE
MOVES ACROSS THE DAKOTAS INTO MN. THIS WILL LEAD TO 2 SFC LOW
CENTERS AT 12Z WED...ONE OVER NW MN AND THE SECOND IN THE VCNTY OF
SRN LAKE MI. OVER THE LAST FEW DAYS...MODELS HAVE PERSISTENTLY
OVERALL TRENDED SLIGHTLY SE WITH EACH SUCCESSIVE MODEL RUN IN REGARD
TO THE SRN SHORTWAVE/SFC LOW. THAT TREND HAS CONTINUED WITH THE 00Z
MODELS. FOR THE FCST AREA...THIS MEANS HEAVIEST PCPN SHOULD PASS BY
TO THE SE OF HERE...AND PCPN SHOULD FALL ALMOST EXCLUSIVELY AS SNOW
AS IT ARRIVES FROM THE S AND SW LATE TONIGHT. THERE IS STILL JUST
ENOUGH UNCERTAINTY IN THERMAL PROFILES TO INCLUDE A MENTION OF -FZRA
CLOSE TO LAKE MI WHERE WARM NOSE ALOFT OF ABOVE FREEZING TEMPS WILL
COME CLOSE TO THAT AREA. UTILIZED MOSTLY A CONSENSUS APPROACH OF ALL
AVBL GUIDANCE...WEIGHTED TOWARD HIGH RES GUIDANCE (NAM/GEM AND NCEP
HRW-ARW/NMM)...TO CONSTRUCT POPS/QPF TONIGHT. RESULT IS PCPN
SPREADING N AND NE INTO THE FCST AREA AFTER 06Z. IT`S POSSIBLE THE
SNOW MAY NOT ARRIVE OVER THE FAR N AND E FCST AREA UNTIL AROUND 12Z
WED. RESULT FOR QPF IS ROUGHLY 0.10 TO 0.25 INCHES BY 12Z...HIGHEST
IN SRN MENOMINEE COUNTY. VIGOROUS DYNAMICS AND HEALTHY ISENTROPIC
ASCENT NOTED ON 290K SFC SHOULD LEAD TO DECENT PCPN RATES DURING
PEAK FORCING WHICH REACHES THE WI BORDER IN THE 09Z-12Z TIME FRAME.
ALTHOUGH MIXING RATIOS OF 3-4G/KG ARE AVBL AROUND 750MB...SHORT
DURATION OF STRONG FORCING AND LOWER SNOW TO WATER RATIOS DOWN TO 10-
15 TO 1 MAKE FOR LOWER CONFIDENCE ON SNOW ACCUMULATIONS REACHING
ADVY LEVEL. AT THIS POINT...CONSENSUS HERE IS TO HOLD OFF ON ADVY
HEADLINES...ESPECIALLY SINCE THIS IS A VERY LATE 2ND PERIOD AND 3RD
PERIOD EVENT. IF NEXT ROUND OF MODEL RUNS TODAY PAINT A SLIGHTLY
HIGHER QPF PICTURE...CAN FORESEE ADVY HEADLINES FOR POSSIBLY THE E
HALF OF THE FCST AREA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 339 PM EDT TUE MAR 24 2015
THE FIRST WAVE OF PRECIPITATION WILL HAVE QUICKLY SHIFTED NORTHEAST
OF THE AREA ON WEDNESDAY...LEAVING THE TRAILING SHORTWAVE AND
SURFACE TROUGH STRETCHING SOUTHWEST ACROSS NORTHERN/WESTERN LAKE
SUPERIOR AT 00Z THURSDAY. EXPECT THERE TO BE SOME RAIN/SNOW SHOWERS
OCCURRING ALONG THIS TROUGH (WETBULB ZERO HEIGHTS SUPPORT A MIX
INITIALLY)...LARGELY OVER WESTERN LAKE SUPERIOR AND OVER THE
KEWEENAW. THE SURFACE-850MB TROUGH WILL THEN SLOWLY SINK SOUTHEAST
ACROSS UPPER MICHIGAN WEDNESDAY NIGHT...LEADING TO MUCH COLDER AIR
TO MOVE INTO THE AREA UNDER NORTHERLY FLOW. 850MB TEMPS WILL DROP
FROM -6C AT 00Z THURSDAY TO -11C BY 12Z AND -17C BY 00Z FRIDAY. THIS
COLDER AIR WILL LEAD TO ENHANCEMENT OF THE SNOW INITIALLY...BEFORE
TRANSITIONING TO PURE LAKE EFFECT DURING THE DAY ON THURSDAY AS THE
DEEPER MOISTURE DEPARTS. THE LOW LEVEL WINDS WILL BE VEERING THROUGH
THE WEDNESDAY NIGHT PERIOD (WESTERLY AT 00Z THURSDAY AND N-NNW BY
12Z THURSDAY)...LIMITING THE FOCUS OF THE TERRAIN ENHANCEMENT
INITIALLY WEDNESDAY EVENING. AS WINDS PERSIST OUT OF THE NORTHERLY
DIRECTION THROUGH THE DAY ON THURSDAY...THE TERRAIN ENHANCEMENT WILL
BECOME FOCUSED AND HAVE THE HIGHEST POPS IN THE NORTHERLY WIND
UPSLOPE AREAS DOWNWIND OF THE OPEN WATER ON LAKE SUPERIOR
(ESSENTIALLY AROUND GOGEBIC/ONTONAGON/MARQUETTE COUNTIES). WHILE
THIS WILL LEAD TO A FAVORABLE PERIOD OF LAKE ENHANCED AND UPSLOPE
SNOW WEDNESDAY NIGHT INTO THURSDAY MORNING...THE SNOW AMOUNTS WILL
DEPEND ON HOW QUICKLY WINDS VEER ON WEDNESDAY NIGHT. WILL FOLLOW THE
GENERAL CONSENSUS ON THE TIMING...WITH THE BEST LAKE ENHANCED QPF
OVER THE KEWEENAW IN THE EVENING AND SPREADING SOUTH TO
GOGEBIC/ONTONAGON/MARQUETTE/BARAGA COUNTIES DURING THE OVERNIGHT
HOURS. SNOW RATIOS WILL START UP AT OR BELOW 10-1 BEFORE TRENDING UP
DURING THE OVERNIGHT HOURS INTO THURSDAY AS THE COLD AIR SURGES INTO
THE AREA AND PUTS THE FOCUS OF THE FORCING CLOSER TO THE DGZ. ALL IN
ALL...HAVE SNOWFALL AMOUNTS WEDNESDAY NIGHT INTO THURSDAY OVER THOSE
PREVIOUSLY MENTIONED FAVORED AREAS OF 3 TO 6 INCHES (AND
POTENTIALLY UP TO 7 INCHES OVER THE PORKIES). IN ADDITION TO THE
SNOW...THE NORTHERLY WINDS WILL BE FAIRLY GUSTY ON THURSDAY
(25-30KTS AND SOME GALE FORCE GUSTS OVER CENTRAL LAKE
SUPERIOR)...WHICH WITH THE FLUFFIER NATURE OF THE SNOW BY THAT TIME
WILL LIKELY LEAD TO SOME BLOWING SNOW ALONG THE LAKE SUPERIOR
SHORELINES.
AS DRY AIR FROM THE CANADIAN HIGH PRESSURE IN MANITOBA NOSES INTO
WESTERN LAKE SUPERIOR ON THURSDAY AFTERNOON...EXPECT THE LAKE
EFFECT TO BEGIN TO DIMINISH AND WILL START LOWERING POPS DURING THE
AFTERNOON AND CONTINUE THE TREND INTO THURSDAY NIGHT. THERE DOES
APPEAR TO BE A FAVORABLE PERIOD OF THE CLOUD BEING WITHIN THE DGZ
LATE THURSDAY AFTERNOON INTO THURSDAY EVENING...WHICH WILL ATTEMPT
TO OFFSET THE DRIER AIR AND LOWERING INVERSION HEIGHTS...BUT DON/T
EXPECT THE ACCUMULATION TO BE TOO SIGNIFICANT (ADDITIONAL AMOUNTS
AROUND 1 INCH ON THURSDAY NIGHT).
AS THE HIGH CONTINUES SOUTH THROUGH MINNESOTA LATE THURSDAY NIGHT
AND INTO WISCONSIN FRIDAY AFTERNOON...A RIDGE WILL SLIDE ACROSS THE
UPPER GREAT LAKES REGION AND BRING AN END TO ANY LINGERING LAKE
EFFECT FRIDAY MORNING. DRY CONDITIONS WILL PERSIST THROUGH FRIDAY
NIGHT AND SATURDAY...AS THE RIDGE LINGERS OVER THE AREA AS THE HIGH
MOVES INTO THE SOUTHEAST CONUS. AFTER BELOW NORMAL TEMPERATURES ON
THURSDAY AND FRIDAY...SATURDAY/S TEMPERATURES WILL REBOUND TOWARDS
NORMAL.
FOCUS THEN TURNS TO A SHORTWAVE COMING ON SHORE IN THE PACIFIC
NORTHWEST FRIDAY NIGHT. THIS WAVE WILL MOVE EAST OVER THE CANADIAN
ROCKIES AND THEN EITHER THROUGH ONTARIO OR THE UPPER GREAT LAKES
REGION LATE SATURDAY NIGHT AND SUNDAY MORNING. OVERALL...MODELS
HAVE BEEN CONSISTENT ON THE TIMING OF THIS FEATURE...THEY JUST VARY
ON THE STRENGTH OF THE UPPER RIDGE OVER THE CENTRAL/SOUTHERN
ROCKIES. THE STRENGTH OF THAT RIDGE WILL DETERMINE IF THE WAVE
DIVES FARTHER SOUTH AND THROUGH THE REGION OR STAYS TO THE NORTH.
FEEL CONFIDENT ON THE TIMING TO SHOW MORE DETAIL IN THAT PORTION OF
THE FORECAST...BUT WILL KEEP POPS STILL IN THE HIGH CHANCE
CATEGORY. WILL KEEP PCPN IN THE FORECAST INTO SUNDAY AND EVEN
SUNDAY NIGHT...AS THERE ARE HINTS OF A SECONDARY WAVE SWEEPING
THROUGH THE AREA. THE PRECIP TYPE STILL IS A LITTLE UNCERTAIN...BUT
THE INITIAL WAVE SHOULD FALL AS SNOW AND THEN MIX WITH OR TURN TO
RAIN ON THE BACK SIDE. THAT POTENTIAL FOR RAIN WILL CONTINUE INTO
SUNDAY...BEFORE COLDER AIR MOVES BACK INTO THE REGION AND SWITCHES
ANY REMAINING PRECIPITATION BACK TO SNOW SUNDAY NIGHT.
THOSE SHORTWAVES WILL SHIFT EAST OF THE AREA SUNDAY NIGHT AND ALLOW
AN UPPER RIDGE TO NOSE EAST INTO THE UPPER GREAT LAKES REGION ON
MONDAY BEFORE FLATTENING ON TUESDAY. THIS WILL ALLOW FOR WARMER
AIR ALOFT TO WORK INTO THE AREA STARTING ON MONDAY AND ESPECIALLY
ON TUESDAY (925MB TEMPS RISING TO AT LEAST 6C). THAT SHOULD PUSH
HIGHS TO OR ABOVE 50 DEGREES FOR MUCH OF THE CWA FOR THE LAST DAY
OF MARCH (NORMAL IS 40-45). LOOKING FARTHER AHEAD...THE PATTERN
LOOKS TO TURN A LITTLE MORE ACTIVE FOR THE SECOND HALF OF NEXT
WEEK...AS THE MODELS REMAIN CONSISTENT ON A STRONGER WAVE MOVE EAST
TOWARDS THE GREAT LAKES REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 151 PM EDT TUE MAR 24 2015
VERY DRY AIR IN THE LOW TO MID LEVELS ASSOCIATED WITH HIGH PRES
MOVING E ACROSS THE LOWER GREAT LAKES TODAY WILL ENSURE VFR
CONDITIONS AT KIWD/KCMX/KSAW THROUGH THIS EVENING. LOW PRES LIFTING
NE TOWARD LAKE MICHIGAN TONIGHT WILL SPREAD SNOW INTO UPPER MI LATE
TONIGHT INTO WED MORNING. IFR CONDITIONS SHOULD REACH KIWD BY 10Z AND
KCMX BY 14Z AND THEN IMPROVE BACK UP TO MVFR BY LATE WED
MORNING/EARLY AFTERNOON. KSAW HAS BEST POTENTIAL FOR HEAVIER SNOW
CLOSER TO TRACK OF SFC LOW SO EXPECT CONDITIONS THERE TO LOWER TO
LIFR SHORTLY AFT 12Z AND THEN IMPROVE BACK TO MVFR BY 16Z AS SYSTEM
LIFTS QUICKLY E.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 557 AM EDT TUE MAR 24 2015
WITH HIGH PRES OVER THE GREAT LAKES REGION SHIFTING E WHILE LOW PRES
DEVELOPING OVER THE SRN PLAINS MOVES NE...WINDS WILL INCREASE TODAY
AND TONIGHT. SINCE PRES GRADIENT REMAINS RELATIVELY WEAK...WINDS
ACROSS LAKE SUPERIOR SHOULD REMAIN MOSTLY UNDER 20KT...THOUGH HIGH
OBS PLATFORMS WILL PROBABLY SEE SOME GUSTS TO AROUND 25KT. WINDS
WILL DIMINISH WED AS LOW PRES TROF SETS UP ACROSS THE LAKE BTWN ONE
LOW PRES CENTER MOVING E TOWARD LAKE SUPERIOR AND THE OTHER LIFTING
NE THRU LWR MI INTO ONTARIO. THE TROF WILL DROP S OF THE LAKE WED
NIGHT...AND WINDS WILL THEN INCREASE INTO THU AS HIGH PRES BUILDS S
TOWARD THE NRN PLAINS AND MUCH COLDER AIR SPREADS SE INTO THE UPPER
LAKES. NORTHERLY WINDS SHOULD INCREASE TO 20-30KT THU...AND IT`S NOT
OUT OF THE QUESTION THAT GALE FORCE GUSTS COULD OCCUR FOR A TIME
OVER CNTRL PORTIONS OF LAKE SUPERIOR. WINDS WILL THEN DIMINISH FRI
AS THE HIGH PRES ARRIVES OVER THE WRN GREAT LAKES. WIND WILL BEGIN
TO RAMP UP AGAIN SAT...ESPECIALLY LATE...AS THE HIGH SHIFTS TO THE
OHIO VALLEY AND LOW PRES DROPS SE INTO MANITOBA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
159 PM EDT TUE MAR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 557 AM EDT TUE MAR 24 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A MESSY COMPLEX OF
SHORTWAVE ENERGY MOVING ACROSS THE PACIFIC NW AND ROCKIES. LEAD
ENERGY IS ALREADY GENERATING SHRA/TSRA ACROSS THE CNTRL PLAINS EARLY
THIS MORNING. CLOSER TO HOME...SHORTWAVE RIDGE OVER MN IS SUPPORTING
SFC HIGH PRES OVER THE GREAT LAKES. ASSOCIATED DRY AIR
MASS/SUBSIDENCE AHEAD OF RIDGE IS RESULTING IN CLEAR SKIES ACROSS
THE UPPER LAKES EARLY THIS MORNING. WITH LIGHT/CALM WIND...TEMPS IN
THE INTERIOR E HALF HAVE FALLEN INTO THE LOWER TEENS AND SINGLE
DIGITS WITH A FEW SPOTS RECENTLY NEAR 0F. OUT W...20S ARE MORE
COMMON WITH A LIGHT S WIND STIRRING.
MID/UPPER RIDGE SHIFTING ACROSS THE WRN GREAT LAKES TODAY ALONG WITH
DRY AIR MASS WILL RESULT IN ABUNDANT SUNSHINE. HIGH WILL REACH THE
40S OVER THE MUCH OF THE W HALF. S TO SE WINDS OFF LAKE MI WILL KEEP
THE E HALF COOLER IN THE 30S...PROBABLY LOW 30S NEAR THE SHORE OF
LAKE MI.
TONIGHT...ATTENTION TURNS TO THE MULTIPLE SHORTWAVES CURRENTLY
MOVING ACROSS THE PACIFIC NW AND ROCKIES. LEAD ENERGY MOVING OUT
ACROSS NE/KS THIS AFTN IS STILL FCST TO TAKE ON A NEGATIVE TILT AS
IT MOVES TO VCNTY OF SRN LAKE MI BY 12Z WED WHILE ANOTHER SHORTWAVE
MOVES ACROSS THE DAKOTAS INTO MN. THIS WILL LEAD TO 2 SFC LOW
CENTERS AT 12Z WED...ONE OVER NW MN AND THE SECOND IN THE VCNTY OF
SRN LAKE MI. OVER THE LAST FEW DAYS...MODELS HAVE PERSISTENTLY
OVERALL TRENDED SLIGHTLY SE WITH EACH SUCCESSIVE MODEL RUN IN REGARD
TO THE SRN SHORTWAVE/SFC LOW. THAT TREND HAS CONTINUED WITH THE 00Z
MODELS. FOR THE FCST AREA...THIS MEANS HEAVIEST PCPN SHOULD PASS BY
TO THE SE OF HERE...AND PCPN SHOULD FALL ALMOST EXCLUSIVELY AS SNOW
AS IT ARRIVES FROM THE S AND SW LATE TONIGHT. THERE IS STILL JUST
ENOUGH UNCERTAINTY IN THERMAL PROFILES TO INCLUDE A MENTION OF -FZRA
CLOSE TO LAKE MI WHERE WARM NOSE ALOFT OF ABOVE FREEZING TEMPS WILL
COME CLOSE TO THAT AREA. UTILIZED MOSTLY A CONSENSUS APPROACH OF ALL
AVBL GUIDANCE...WEIGHTED TOWARD HIGH RES GUIDANCE (NAM/GEM AND NCEP
HRW-ARW/NMM)...TO CONSTRUCT POPS/QPF TONIGHT. RESULT IS PCPN
SPREADING N AND NE INTO THE FCST AREA AFTER 06Z. IT`S POSSIBLE THE
SNOW MAY NOT ARRIVE OVER THE FAR N AND E FCST AREA UNTIL AROUND 12Z
WED. RESULT FOR QPF IS ROUGHLY 0.10 TO 0.25 INCHES BY 12Z...HIGHEST
IN SRN MENOMINEE COUNTY. VIGOROUS DYNAMICS AND HEALTHY ISENTROPIC
ASCENT NOTED ON 290K SFC SHOULD LEAD TO DECENT PCPN RATES DURING
PEAK FORCING WHICH REACHES THE WI BORDER IN THE 09Z-12Z TIME FRAME.
ALTHOUGH MIXING RATIOS OF 3-4G/KG ARE AVBL AROUND 750MB...SHORT
DURATION OF STRONG FORCING AND LOWER SNOW TO WATER RATIOS DOWN TO 10-
15 TO 1 MAKE FOR LOWER CONFIDENCE ON SNOW ACCUMULATIONS REACHING
ADVY LEVEL. AT THIS POINT...CONSENSUS HERE IS TO HOLD OFF ON ADVY
HEADLINES...ESPECIALLY SINCE THIS IS A VERY LATE 2ND PERIOD AND 3RD
PERIOD EVENT. IF NEXT ROUND OF MODEL RUNS TODAY PAINT A SLIGHTLY
HIGHER QPF PICTURE...CAN FORESEE ADVY HEADLINES FOR POSSIBLY THE E
HALF OF THE FCST AREA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 517 AM EDT TUE MAR 24 2015
FCST MODELS CONTINUE TO MERGE ON A THEME OF HAVING THE INITIAL LOW
FROM THE SW OVER CENTRAL LAKE MI AROUND 12Z WEDNESDAY. THE RESULT
HAS BEEN A TREND TO LESS PRECIP AND MORE IN THE FORM OF SNOW INSTEAD
OF FREEZING RAIN WEDNESDAY MORNING.
PRECIP WILL OVERSPREAD THE REST OF THE CWA WEDNESDAY MORNING. THIS
QUICK BLAST OF MOISTURE WILL ALREADY BE PULLING OUT OF THE SW CORNER
OF UPPER MI BY 18Z WEDNESDAY...AND IF THE 23/18Z RUN OF THE CANADIAN
IS CORRECT MUCH OF THE SW AND CENTRAL CWA. THIS WILL BE WHILE THE
SFC LOW SHIFTS ACROSS E UPPER MI AND NW LAKE HURON BY 18Z...AND
GENERALLY BETWEEN CYLD AND CYXR IN SE ONTARIO BY 00Z THURSDAY. WITH
SFC TEMPS GETTING INTO THE UPPER 30S AND LOW 40S WEDNESDAY
AFTERNOON...SNOW WILL BE DIFFICULT TO MAINTAIN. WHILE A MIX IS
REPRESENTED IN THE FCST...UPPER MI WILL BE IN A LULL...WITH MUCH OF
THE BEST MOISTURE WILL BE ALREADY GONE.
UPDATED THE SPS TO INCLUDE THE COUNTIES OF MENOMINEE TO ALGER AND
E...WHERE THE GREATEST POTENTIAL FOR OVER 2IN OF SNOW EXISTS...ALONG
WITH A BRIEF PERIOD OF FREEZING RAIN.
WILL NEED TO WAIT UNTIL THE SECONDARY SFC LOW /OVER NW MN AT 12Z
WEDNESDAY/ EXITS THE PICTURE. IT SHOULD MOVE OVER NE MN AT 18Z
WEDNEDAY...AND JOIN FORCES WITH THE MAIN LOW EARLY WEDNESDAY EVENING
OVER LAKE SUPERIOR AND SE ONTARIO. 850MB TEMPS STILL AROUND -5C AT
00Z THURSDAY WILL FALL TO AROUND -15C OVER THE W BY 12Z THURSDAY ON
N-NW WINDS. THE RESULT...WITH THE ASSISTANCE OF THE SIZABLE 500MB
TROUGH OVERHEAD CONTINUING TO BRING A SERIES OF SHORTWAVES ACROSS
UPPER MI...WILL BE LIGHT TO AT TIMES MODERATE LES THROUGH THURSDAY
EVENING.
THE 500MB TROUGH WILL EVENTUALLY SHIFT TO OUR SE...MAKING WAY FOR A
RIDGE SATURDAY INTO EARLY SUNDAY. AT THIS POINT...WITH HIGH PRESSURE
AT THE SFC AND ALOFT...DRY WEATHER IS FIGURED FROM LATE MORNING
FRIDAY THROUGH THE DAY SATURDAY.
THE 00Z RUN OF THE ECMWF IS MORE ROBUST WITH THE PRECIP SUNDAY
MORNING. LOOKS LIKE ANOTHER POTENTIAL RAIN/SNOW SITUATION. WHILE THE
ECMWF WOULD INDICATE WARMER AIR AND A BETTER CHANCE OF RAIN...THE
GFS IS MUCH COOLER AND WOULD GIVE MAINLY RAIN. WILL CONTINUE WITH A
MODEL BLEND FOR THIS PERIOD...UNTIL A MORE SOLID CONSENSUS IS
DEVELOPED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 151 PM EDT TUE MAR 24 2015
VERY DRY AIR IN THE LOW TO MID LEVELS ASSOCIATED WITH HIGH PRES
MOVING E ACROSS THE LOWER GREAT LAKES TODAY WILL ENSURE VFR
CONDITIONS AT KIWD/KCMX/KSAW THROUGH THIS EVENING. LOW PRES LIFTING
NE TOWARD LAKE MICHIGAN TONIGHT WILL SPREAD SNOW INTO UPPER MI LATE
TONIGHT INTO WED MORNING. IFR CONDITIONS SHOULD REACH KIWD BY 10Z AND
KCMX BY 14Z AND THEN IMPROVE BACK UP TO MVFR BY LATE WED
MORNING/EARLY AFTERNOON. KSAW HAS BEST POTENTIAL FOR HEAVIER SNOW
CLOSER TO TRACK OF SFC LOW SO EXPECT CONDITIONS THERE TO LOWER TO
LIFR SHORTLY AFT 12Z AND THEN IMPROVE BACK TO MVFR BY 16Z AS SYSTEM
LIFTS QUICKLY E.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 557 AM EDT TUE MAR 24 2015
WITH HIGH PRES OVER THE GREAT LAKES REGION SHIFTING E WHILE LOW PRES
DEVELOPING OVER THE SRN PLAINS MOVES NE...WINDS WILL INCREASE TODAY
AND TONIGHT. SINCE PRES GRADIENT REMAINS RELATIVELY WEAK...WINDS
ACROSS LAKE SUPERIOR SHOULD REMAIN MOSTLY UNDER 20KT...THOUGH HIGH
OBS PLATFORMS WILL PROBABLY SEE SOME GUSTS TO AROUND 25KT. WINDS
WILL DIMINISH WED AS LOW PRES TROF SETS UP ACROSS THE LAKE BTWN ONE
LOW PRES CENTER MOVING E TOWARD LAKE SUPERIOR AND THE OTHER LIFTING
NE THRU LWR MI INTO ONTARIO. THE TROF WILL DROP S OF THE LAKE WED
NIGHT...AND WINDS WILL THEN INCREASE INTO THU AS HIGH PRES BUILDS S
TOWARD THE NRN PLAINS AND MUCH COLDER AIR SPREADS SE INTO THE UPPER
LAKES. NORTHERLY WINDS SHOULD INCREASE TO 20-30KT THU...AND IT`S NOT
OUT OF THE QUESTION THAT GALE FORCE GUSTS COULD OCCUR FOR A TIME
OVER CNTRL PORTIONS OF LAKE SUPERIOR. WINDS WILL THEN DIMINISH FRI
AS THE HIGH PRES ARRIVES OVER THE WRN GREAT LAKES. WIND WILL BEGIN
TO RAMP UP AGAIN SAT...ESPECIALLY LATE...AS THE HIGH SHIFTS TO THE
OHIO VALLEY AND LOW PRES DROPS SE INTO MANITOBA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
716 AM EDT TUE MAR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 557 AM EDT TUE MAR 24 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A MESSY COMPLEX OF
SHORTWAVE ENERGY MOVING ACROSS THE PACIFIC NW AND ROCKIES. LEAD
ENERGY IS ALREADY GENERATING SHRA/TSRA ACROSS THE CNTRL PLAINS EARLY
THIS MORNING. CLOSER TO HOME...SHORTWAVE RIDGE OVER MN IS SUPPORTING
SFC HIGH PRES OVER THE GREAT LAKES. ASSOCIATED DRY AIR
MASS/SUBSIDENCE AHEAD OF RIDGE IS RESULTING IN CLEAR SKIES ACROSS
THE UPPER LAKES EARLY THIS MORNING. WITH LIGHT/CALM WIND...TEMPS IN
THE INTERIOR E HALF HAVE FALLEN INTO THE LOWER TEENS AND SINGLE
DIGITS WITH A FEW SPOTS RECENTLY NEAR 0F. OUT W...20S ARE MORE
COMMON WITH A LIGHT S WIND STIRRING.
MID/UPPER RIDGE SHIFTING ACROSS THE WRN GREAT LAKES TODAY ALONG WITH
DRY AIR MASS WILL RESULT IN ABUNDANT SUNSHINE. HIGH WILL REACH THE
40S OVER THE MUCH OF THE W HALF. S TO SE WINDS OFF LAKE MI WILL KEEP
THE E HALF COOLER IN THE 30S...PROBABLY LOW 30S NEAR THE SHORE OF
LAKE MI.
TONIGHT...ATTENTION TURNS TO THE MULTIPLE SHORTWAVES CURRENTLY
MOVING ACROSS THE PACIFIC NW AND ROCKIES. LEAD ENERGY MOVING OUT
ACROSS NE/KS THIS AFTN IS STILL FCST TO TAKE ON A NEGATIVE TILT AS
IT MOVES TO VCNTY OF SRN LAKE MI BY 12Z WED WHILE ANOTHER SHORTWAVE
MOVES ACROSS THE DAKOTAS INTO MN. THIS WILL LEAD TO 2 SFC LOW
CENTERS AT 12Z WED...ONE OVER NW MN AND THE SECOND IN THE VCNTY OF
SRN LAKE MI. OVER THE LAST FEW DAYS...MODELS HAVE PERSISTENTLY
OVERALL TRENDED SLIGHTLY SE WITH EACH SUCCESSIVE MODEL RUN IN REGARD
TO THE SRN SHORTWAVE/SFC LOW. THAT TREND HAS CONTINUED WITH THE 00Z
MODELS. FOR THE FCST AREA...THIS MEANS HEAVIEST PCPN SHOULD PASS BY
TO THE SE OF HERE...AND PCPN SHOULD FALL ALMOST EXCLUSIVELY AS SNOW
AS IT ARRIVES FROM THE S AND SW LATE TONIGHT. THERE IS STILL JUST
ENOUGH UNCERTAINTY IN THERMAL PROFILES TO INCLUDE A MENTION OF -FZRA
CLOSE TO LAKE MI WHERE WARM NOSE ALOFT OF ABOVE FREEZING TEMPS WILL
COME CLOSE TO THAT AREA. UTILIZED MOSTLY A CONSENSUS APPROACH OF ALL
AVBL GUIDANCE...WEIGHTED TOWARD HIGH RES GUIDANCE (NAM/GEM AND NCEP
HRW-ARW/NMM)...TO CONSTRUCT POPS/QPF TONIGHT. RESULT IS PCPN
SPREADING N AND NE INTO THE FCST AREA AFTER 06Z. IT`S POSSIBLE THE
SNOW MAY NOT ARRIVE OVER THE FAR N AND E FCST AREA UNTIL AROUND 12Z
WED. RESULT FOR QPF IS ROUGHLY 0.10 TO 0.25 INCHES BY 12Z...HIGHEST
IN SRN MENOMINEE COUNTY. VIGOROUS DYNAMICS AND HEALTHY ISENTROPIC
ASCENT NOTED ON 290K SFC SHOULD LEAD TO DECENT PCPN RATES DURING
PEAK FORCING WHICH REACHES THE WI BORDER IN THE 09Z-12Z TIME FRAME.
ALTHOUGH MIXING RATIOS OF 3-4G/KG ARE AVBL AROUND 750MB...SHORT
DURATION OF STRONG FORCING AND LOWER SNOW TO WATER RATIOS DOWN TO 10-
15 TO 1 MAKE FOR LOWER CONFIDENCE ON SNOW ACCUMULATIONS REACHING
ADVY LEVEL. AT THIS POINT...CONSENSUS HERE IS TO HOLD OFF ON ADVY
HEADLINES...ESPECIALLY SINCE THIS IS A VERY LATE 2ND PERIOD AND 3RD
PERIOD EVENT. IF NEXT ROUND OF MODEL RUNS TODAY PAINT A SLIGHTLY
HIGHER QPF PICTURE...CAN FORESEE ADVY HEADLINES FOR POSSIBLY THE E
HALF OF THE FCST AREA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 517 AM EDT TUE MAR 24 2015
FCST MODELS CONTINUE TO MERGE ON A THEME OF HAVING THE INITIAL LOW
FROM THE SW OVER CENTRAL LAKE MI AROUND 12Z WEDNESDAY. THE RESULT
HAS BEEN A TREND TO LESS PRECIP AND MORE IN THE FORM OF SNOW INSTEAD
OF FREEZING RAIN WEDNESDAY MORNING.
PRECIP WILL OVERSPREAD THE REST OF THE CWA WEDNESDAY MORNING. THIS
QUICK BLAST OF MOISTURE WILL ALREADY BE PULLING OUT OF THE SW CORNER
OF UPPER MI BY 18Z WEDNESDAY...AND IF THE 23/18Z RUN OF THE CANADIAN
IS CORRECT MUCH OF THE SW AND CENTRAL CWA. THIS WILL BE WHILE THE
SFC LOW SHIFTS ACROSS E UPPER MI AND NW LAKE HURON BY 18Z...AND
GENERALLY BETWEEN CYLD AND CYXR IN SE ONTARIO BY 00Z THURSDAY. WITH
SFC TEMPS GETTING INTO THE UPPER 30S AND LOW 40S WEDNESDAY
AFTERNOON...SNOW WILL BE DIFFICULT TO MAINTAIN. WHILE A MIX IS
REPRESENTED IN THE FCST...UPPER MI WILL BE IN A LULL...WITH MUCH OF
THE BEST MOISTURE WILL BE ALREADY GONE.
UPDATED THE SPS TO INCLUDE THE COUNTIES OF MENOMINEE TO ALGER AND
E...WHERE THE GREATEST POTENTIAL FOR OVER 2IN OF SNOW EXISTS...ALONG
WITH A BRIEF PERIOD OF FREEZING RAIN.
WILL NEED TO WAIT UNTIL THE SECONDARY SFC LOW /OVER NW MN AT 12Z
WEDNESDAY/ EXITS THE PICTURE. IT SHOULD MOVE OVER NE MN AT 18Z
WEDNEDAY...AND JOIN FORCES WITH THE MAIN LOW EARLY WEDNESDAY EVENING
OVER LAKE SUPERIOR AND SE ONTARIO. 850MB TEMPS STILL AROUND -5C AT
00Z THURSDAY WILL FALL TO AROUND -15C OVER THE W BY 12Z THURSDAY ON
N-NW WINDS. THE RESULT...WITH THE ASSISTANCE OF THE SIZABLE 500MB
TROUGH OVERHEAD CONTINUING TO BRING A SERIES OF SHORTWAVES ACROSS
UPPER MI...WILL BE LIGHT TO AT TIMES MODERATE LES THROUGH THURSDAY
EVENING.
THE 500MB TROUGH WILL EVENTUALLY SHIFT TO OUR SE...MAKING WAY FOR A
RIDGE SATURDAY INTO EARLY SUNDAY. AT THIS POINT...WITH HIGH PRESSURE
AT THE SFC AND ALOFT...DRY WEATHER IS FIGURED FROM LATE MORNING
FRIDAY THROUGH THE DAY SATURDAY.
THE 00Z RUN OF THE ECMWF IS MORE ROBUST WITH THE PRECIP SUNDAY
MORNING. LOOKS LIKE ANOTHER POTENTIAL RAIN/SNOW SITUATION. WHILE THE
ECMWF WOULD INDICATE WARMER AIR AND A BETTER CHANCE OF RAIN...THE
GFS IS MUCH COOLER AND WOULD GIVE MAINLY RAIN. WILL CONTINUE WITH A
MODEL BLEND FOR THIS PERIOD...UNTIL A MORE SOLID CONSENSUS IS
DEVELOPED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 716 AM EDT TUE MAR 24 2015
VERY DRY AIR IN THE LOW TO MID LEVELS ASSOCIATED WITH HIGH PRES
MOVING E ACROSS THE LOWER GREAT LAKES TODAY WILL ENSURE VFR
CONDITIONS AT KIWD/KCMX/KSAW THROUGH THIS EVENING. LOW PRES LIFTING
NE TOWARD LAKE MICHIGAN TONIGHT WILL SPREAD SNOW INTO UPPER MI LATE
TONIGHT. NEAR THE END OF THE FCST PERIOD...IFR CONDITIONS SHOULD
REACH KIWD WITH MVFR AT KCMX/KSAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 557 AM EDT TUE MAR 24 2015
WITH HIGH PRES OVER THE GREAT LAKES REGION SHIFTING E WHILE LOW PRES
DEVELOPING OVER THE SRN PLAINS MOVES NE...WINDS WILL INCREASE TODAY
AND TONIGHT. SINCE PRES GRADIENT REMAINS RELATIVELY WEAK...WINDS
ACROSS LAKE SUPERIOR SHOULD REMAIN MOSTLY UNDER 20KT...THOUGH HIGH
OBS PLATFORMS WILL PROBABLY SEE SOME GUSTS TO AROUND 25KT. WINDS
WILL DIMINISH WED AS LOW PRES TROF SETS UP ACROSS THE LAKE BTWN ONE
LOW PRES CENTER MOVING E TOWARD LAKE SUPERIOR AND THE OTHER LIFTING
NE THRU LWR MI INTO ONTARIO. THE TROF WILL DROP S OF THE LAKE WED
NIGHT...AND WINDS WILL THEN INCREASE INTO THU AS HIGH PRES BUILDS S
TOWARD THE NRN PLAINS AND MUCH COLDER AIR SPREADS SE INTO THE UPPER
LAKES. NORTHERLY WINDS SHOULD INCREASE TO 20-30KT THU...AND IT`S NOT
OUT OF THE QUESTION THAT GALE FORCE GUSTS COULD OCCUR FOR A TIME
OVER CNTRL PORTIONS OF LAKE SUPERIOR. WINDS WILL THEN DIMINISH FRI
AS THE HIGH PRES ARRIVES OVER THE WRN GREAT LAKES. WIND WILL BEGIN
TO RAMP UP AGAIN SAT...ESPECIALLY LATE...AS THE HIGH SHIFTS TO THE
OHIO VALLEY AND LOW PRES DROPS SE INTO MANITOBA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
558 AM EDT TUE MAR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 557 AM EDT TUE MAR 24 2015
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A MESSY COMPLEX OF
SHORTWAVE ENERGY MOVING ACROSS THE PACIFIC NW AND ROCKIES. LEAD
ENERGY IS ALREADY GENERATING SHRA/TSRA ACROSS THE CNTRL PLAINS EARLY
THIS MORNING. CLOSER TO HOME...SHORTWAVE RIDGE OVER MN IS SUPPORTING
SFC HIGH PRES OVER THE GREAT LAKES. ASSOCIATED DRY AIR
MASS/SUBSIDENCE AHEAD OF RIDGE IS RESULTING IN CLEAR SKIES ACROSS
THE UPPER LAKES EARLY THIS MORNING. WITH LIGHT/CALM WIND...TEMPS IN
THE INTERIOR E HALF HAVE FALLEN INTO THE LOWER TEENS AND SINGLE
DIGITS WITH A FEW SPOTS RECENTLY NEAR 0F. OUT W...20S ARE MORE
COMMON WITH A LIGHT S WIND STIRRING.
MID/UPPER RIDGE SHIFTING ACROSS THE WRN GREAT LAKES TODAY ALONG WITH
DRY AIR MASS WILL RESULT IN ABUNDANT SUNSHINE. HIGH WILL REACH THE
40S OVER THE MUCH OF THE W HALF. S TO SE WINDS OFF LAKE MI WILL KEEP
THE E HALF COOLER IN THE 30S...PROBABLY LOW 30S NEAR THE SHORE OF
LAKE MI.
TONIGHT...ATTENTION TURNS TO THE MULTIPLE SHORTWAVES CURRENTLY
MOVING ACROSS THE PACIFIC NW AND ROCKIES. LEAD ENERGY MOVING OUT
ACROSS NE/KS THIS AFTN IS STILL FCST TO TAKE ON A NEGATIVE TILT AS
IT MOVES TO VCNTY OF SRN LAKE MI BY 12Z WED WHILE ANOTHER SHORTWAVE
MOVES ACROSS THE DAKOTAS INTO MN. THIS WILL LEAD TO 2 SFC LOW
CENTERS AT 12Z WED...ONE OVER NW MN AND THE SECOND IN THE VCNTY OF
SRN LAKE MI. OVER THE LAST FEW DAYS...MODELS HAVE PERSISTENTLY
OVERALL TRENDED SLIGHTLY SE WITH EACH SUCCESSIVE MODEL RUN IN REGARD
TO THE SRN SHORTWAVE/SFC LOW. THAT TREND HAS CONTINUED WITH THE 00Z
MODELS. FOR THE FCST AREA...THIS MEANS HEAVIEST PCPN SHOULD PASS BY
TO THE SE OF HERE...AND PCPN SHOULD FALL ALMOST EXCLUSIVELY AS SNOW
AS IT ARRIVES FROM THE S AND SW LATE TONIGHT. THERE IS STILL JUST
ENOUGH UNCERTAINTY IN THERMAL PROFILES TO INCLUDE A MENTION OF -FZRA
CLOSE TO LAKE MI WHERE WARM NOSE ALOFT OF ABOVE FREEZING TEMPS WILL
COME CLOSE TO THAT AREA. UTILIZED MOSTLY A CONSENSUS APPROACH OF ALL
AVBL GUIDANCE...WEIGHTED TOWARD HIGH RES GUIDANCE (NAM/GEM AND NCEP
HRW-ARW/NMM)...TO CONSTRUCT POPS/QPF TONIGHT. RESULT IS PCPN
SPREADING N AND NE INTO THE FCST AREA AFTER 06Z. IT`S POSSIBLE THE
SNOW MAY NOT ARRIVE OVER THE FAR N AND E FCST AREA UNTIL AROUND 12Z
WED. RESULT FOR QPF IS ROUGHLY 0.10 TO 0.25 INCHES BY 12Z...HIGHEST
IN SRN MENOMINEE COUNTY. VIGOROUS DYNAMICS AND HEALTHY ISENTROPIC
ASCENT NOTED ON 290K SFC SHOULD LEAD TO DECENT PCPN RATES DURING
PEAK FORCING WHICH REACHES THE WI BORDER IN THE 09Z-12Z TIME FRAME.
ALTHOUGH MIXING RATIOS OF 3-4G/KG ARE AVBL AROUND 750MB...SHORT
DURATION OF STRONG FORCING AND LOWER SNOW TO WATER RATIOS DOWN TO 10-
15 TO 1 MAKE FOR LOWER CONFIDENCE ON SNOW ACCUMULATIONS REACHING
ADVY LEVEL. AT THIS POINT...CONSENSUS HERE IS TO HOLD OFF ON ADVY
HEADLINES...ESPECIALLY SINCE THIS IS A VERY LATE 2ND PERIOD AND 3RD
PERIOD EVENT. IF NEXT ROUND OF MODEL RUNS TODAY PAINT A SLIGHTLY
HIGHER QPF PICTURE...CAN FORESEE ADVY HEADLINES FOR POSSIBLY THE E
HALF OF THE FCST AREA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 517 AM EDT TUE MAR 24 2015
FCST MODELS CONTINUE TO MERGE ON A THEME OF HAVING THE INITIAL LOW
FROM THE SW OVER CENTRAL LAKE MI AROUND 12Z WEDNESDAY. THE RESULT
HAS BEEN A TREND TO LESS PRECIP AND MORE IN THE FORM OF SNOW INSTEAD
OF FREEZING RAIN WEDNESDAY MORNING.
PRECIP WILL OVERSPREAD THE REST OF THE CWA WEDNESDAY MORNING. THIS
QUICK BLAST OF MOISTURE WILL ALREADY BE PULLING OUT OF THE SW CORNER
OF UPPER MI BY 18Z WEDNESDAY...AND IF THE 23/18Z RUN OF THE CANADIAN
IS CORRECT MUCH OF THE SW AND CENTRAL CWA. THIS WILL BE WHILE THE
SFC LOW SHIFTS ACROSS E UPPER MI AND NW LAKE HURON BY 18Z...AND
GENERALLY BETWEEN CYLD AND CYXR IN SE ONTARIO BY 00Z THURSDAY. WITH
SFC TEMPS GETTING INTO THE UPPER 30S AND LOW 40S WEDNESDAY
AFTERNOON...SNOW WILL BE DIFFICULT TO MAINTAIN. WHILE A MIX IS
REPRESENTED IN THE FCST...UPPER MI WILL BE IN A LULL...WITH MUCH OF
THE BEST MOISTURE WILL BE ALREADY GONE.
UPDATED THE SPS TO INCLUDE THE COUNTIES OF MENOMINEE TO ALGER AND
E...WHERE THE GREATEST POTENTIAL FOR OVER 2IN OF SNOW EXISTS...ALONG
WITH A BRIEF PERIOD OF FREEZING RAIN.
WILL NEED TO WAIT UNTIL THE SECONDARY SFC LOW /OVER NW MN AT 12Z
WEDNESDAY/ EXITS THE PICTURE. IT SHOULD MOVE OVER NE MN AT 18Z
WEDNEDAY...AND JOIN FORCES WITH THE MAIN LOW EARLY WEDNESDAY EVENING
OVER LAKE SUPERIOR AND SE ONTARIO. 850MB TEMPS STILL AROUND -5C AT
00Z THURSDAY WILL FALL TO AROUND -15C OVER THE W BY 12Z THURSDAY ON
N-NW WINDS. THE RESULT...WITH THE ASSISTANCE OF THE SIZABLE 500MB
TROUGH OVERHEAD CONTINUING TO BRING A SERIES OF SHORTWAVES ACROSS
UPPER MI...WILL BE LIGHT TO AT TIMES MODERATE LES THROUGH THURSDAY
EVENING.
THE 500MB TROUGH WILL EVENTUALLY SHIFT TO OUR SE...MAKING WAY FOR A
RIDGE SATURDAY INTO EARLY SUNDAY. AT THIS POINT...WITH HIGH PRESSURE
AT THE SFC AND ALOFT...DRY WEATHER IS FIGURED FROM LATE MORNING
FRIDAY THROUGH THE DAY SATURDAY.
THE 00Z RUN OF THE ECMWF IS MORE ROBUST WITH THE PRECIP SUNDAY
MORNING. LOOKS LIKE ANOTHER POTENTIAL RAIN/SNOW SITUATION. WHILE THE
ECMWF WOULD INDICATE WARMER AIR AND A BETTER CHANCE OF RAIN...THE
GFS IS MUCH COOLER AND WOULD GIVE MAINLY RAIN. WILL CONTINUE WITH A
MODEL BLEND FOR THIS PERIOD...UNTIL A MORE SOLID CONSENSUS IS
DEVELOPED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 129 AM EDT TUE MAR 24 2015
VERY DRY AIR IN THE LOW TO MID LEVELS ASSOCIATED WITH HIGH PRES
BUILDING TOWARD THE ERN GREAT LAKES WILL BRING VFR CONDITIONS TO
KIWD/KCMX/KSAW THROUGH THE FCST PERIOD ALONG WITH LIGHT SOUTHERLY
WINDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 557 AM EDT TUE MAR 24 2015
WITH HIGH PRES OVER THE GREAT LAKES REGION SHIFTING E WHILE LOW PRES
DEVELOPING OVER THE SRN PLAINS MOVES NE...WINDS WILL INCREASE TODAY
AND TONIGHT. SINCE PRES GRADIENT REMAINS RELATIVELY WEAK...WINDS
ACROSS LAKE SUPERIOR SHOULD REMAIN MOSTLY UNDER 20KT...THOUGH HIGH
OBS PLATFORMS WILL PROBABLY SEE SOME GUSTS TO AROUND 25KT. WINDS
WILL DIMINISH WED AS LOW PRES TROF SETS UP ACROSS THE LAKE BTWN ONE
LOW PRES CENTER MOVING E TOWARD LAKE SUPERIOR AND THE OTHER LIFTING
NE THRU LWR MI INTO ONTARIO. THE TROF WILL DROP S OF THE LAKE WED
NIGHT...AND WINDS WILL THEN INCREASE INTO THU AS HIGH PRES BUILDS S
TOWARD THE NRN PLAINS AND MUCH COLDER AIR SPREADS SE INTO THE UPPER
LAKES. NORTHERLY WINDS SHOULD INCREASE TO 20-30KT THU...AND IT`S NOT
OUT OF THE QUESTION THAT GALE FORCE GUSTS COULD OCCUR FOR A TIME
OVER CNTRL PORTIONS OF LAKE SUPERIOR. WINDS WILL THEN DIMINISH FRI
AS THE HIGH PRES ARRIVES OVER THE WRN GREAT LAKES. WIND WILL BEGIN
TO RAMP UP AGAIN SAT...ESPECIALLY LATE...AS THE HIGH SHIFTS TO THE
OHIO VALLEY AND LOW PRES DROPS SE INTO MANITOBA.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KF
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1248 PM CDT TUE MAR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM CDT TUE MAR 24 2015
TOUGH FORECAST AHEAD FOR THIS AFTERNOON AND TONIGHT ON PTYPE AND
RESULTING PRECIPITATION AMOUNTS. THERE WAS QUITE THE DIFFERENCE
OUT THE GATE WITH THE 00Z RUNS BETWEEN THE NAM/GFS VERSUS THE
ECMWF/CANADIAN ON THE LAYOUT OF THE PRECIPITATION PATTERN
DEVELOPING LATER THIS AFTERNOON AND SPREADING ACROSS THE FA
TONIGHT. THE ECMWF AND CANADIAN ARE MUCH FARTHER SOUTH ON THE QPF
AXIS WITH A QUARTER INCH TONIGHT BARELY ACROSS THE SOUTHEAST PART
OF MN WHILE THE NAM/GFS HAVE THE QUARTER INCH INTO THE TWIN
CITIES. A CHECK ON RAP RUNS OVERNIGHT INDICATED A QPF PATTERN
DEVELOPING LIKE WHAT THE ECMWF AND CANADIAN ARE SHOWING. WE
BELIEVE PART OF REASON FOR THE DIFFERENCE IS THE CONVECTION
ONGOING TO OUR SOUTH THIS MORNING WITH STRONGER ACTIVITY PROGGED
FOR THIS AFTERNOON. THE NOSE OF THE 925-850MB MOISTURE TRANSPORT
WITH THE ECMWF JUST REACHES UP INTO NE IA THIS EVENING AND THEN
PASSES ACROSS SOUTHERN WI THIS EVENING. OUR INTERNAL MPX ARW-WRF
IS ALSO SHOWING THE QPF AXIS FURTHER SOUTH AS WELL. PTYPE THIS
AFTERNOON IS IN QUESTION WITH THE HRRR AND RAP SOUNDINGS
INDICATING SURFACE DEW POINTS RISING INTO THE LOWER AND MIDDLE 30S
ACROSS SOUTHERN MN WITH ALL RAIN INDICATED. THEY MAY BE TOO WARM
AS OUR MPX WRF SHOWS A CHANGE OVER TO SNOW ACROSS SOUTH CENTRAL MN
IN THE 21Z-24Z TIME FRAME ALONG WITH SOME FREEZING RAIN. HEADING
THROUGH THE EVENING...A DEEP MID LEVEL WAVE WILL PASS ACROSS IA/MO
WITH A DEFORMATION ZONE FROM NEAR KAEL TO KEAU. THIS IS THE ZONE
FOR 2 TO 4 INCHES OF SNOW ACCUMULATION TONIGHT WITH MUCH OF IT
OCCURRING BEFORE 06Z. SNOW AMOUNTS ARE LESS TO THE NORTHWEST WITH
AN INCH OR TWO IN THE TWIN CITIES WITH AROUND AN INCH AT ST.
CLOUD. BASED ON PTYPE ISSUES THIS AFTERNOON ALONG WITH THE SNOW
TONIGHT COUPLED WITH SOME MIXED SLEET AND FREEZING RAIN...WE
ISSUED A WINTER WEATHER ADVISORY FOR SOUTH CENTRAL MN BEGINNING
LATE THIS AFTERNOON WITH THE ADVISORY SPREADING NORTHEAST ACROSS
MUCH OF WEST CENTRAL WI FOR TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 410 AM CDT TUE MAR 24 2015
THE EXTENDED IS ACTUALLY LOOKING FAIRLY QUIET WITH THE MAIN
HAPPENINGS BEING THAT OF A PATTERN SHIFT...WITH A HIGHLY AMPLIFIED
PATTERN THIS WORK WEEK FLATTENING OUT AND BECOMING MORE ZONAL THIS
WEEKEND INTO NEXT WEEK. THE RESULT...TEMPS WILL REMAIN WELL BELOW
NORMAL THE REST OF THIS WORK WEEK...BUT BY THE WEEKEND...THEY WILL
REBOUND BACK TO NEAR OR EVEN A LITTLE ABOVE NORMAL.
THE LONG TERM WILL START WITH TONIGHTS TROUBLE MAKER PUSHING OUT OF
THE MPX AREA WEDNESDAY MORNING. GUIDANCE HAS CONTINUED TO PUSH WRAP
AROUND PRECIP WED/WED NIGHT FARTHER NORTH. IT IS LOOKING MORE AND
MORE LIKELY THAT THE MPX AREA WILL REMAIN DRY THIS PERIOD AS THE
WRAP AROUND MOISTURE STAYS CLOSER TO THE NRN SFC LOW THAT WILL BE
TRACKING ACROSS THE ARROWHEAD. HAVE CONTINUED THE TREND OF CUTTING
BACK POPS ON WEDNESDAY...WITH WED/WED NIGHT NOW BASICALLY DRY SOUTH
OF I-94. WHAT LOOKS MORE CERTAIN FOR WEDNESDAY ARE BREEZY
CONDITIONS. THE NAM SHOWS 3 HR PRESSURE RISES OF ABOUT 6 MB
FOLLOWING THE SFC LOW ACROSS THE ARROWHEAD...WITH 3 MB/3 HR RISES
ALL THE WAY DOWN INTO CENTRAL MN. IN ADDITION...BUFR SOUNDINGS UP AT
AXN SHOW MID CHANNEL MIX DOWN WINDS NEAR 35 KTS WITH TOP OF THE
CHANNEL WINDS AROUND 40 KTS. AS A RESULT...GAVE FORECAST WIND SPEEDS
A PRETTY GOOD BOOST FOR WEDNESDAY...WITH BORDERLINE WIND ADVY WINDS
NOW IN PLACE ACROSS WEST CENTRAL MN.
FOR THURSDAY AND FRIDAY...THE H5 FLOW BECOMES ALMOST NORTHERLY...
WHICH WILL ALLOW A 1035MB HIGH TO DROP DOWN OUT OF CANADA. WITH H85
TEMPS DOWN BETWEEN -6 TO -10C...WE WILL SEE HIGHS REMAIN IN THE 30S
BOTH DAYS...WITH SOME LOWS IN THE SINGLE DIGITS NOT OUT OF THE
QUESTION FRIDAY MORNING AS THE SFC HIGH SETTLES OVER MN AND OUR SNOW
COVER. THE ONE CHANGE SEEN WITH THE GUIDANCE THIS PERIOD IS THE
GEM/GFS/ECMWF ARE ALL SHOWING A QUICK HIT OF LIGHT PRECIP WORKING
ACROSS THE ERN DAKOTAS AND FAR WRN MN FRI/FRI NIGHT AS SHORT WAVE
ENERGY DROPPING DOWN IN THE NRLY FLOW WORKS WITH THE BAROCLINIC ZONE
ON THE BACKSIDE OF THE HIGH TO PRODUCE SOME LIGHT QPF. STILL HAVE A
DRY FORECAST OUT THAT DIRECTION...BUT IF THIS TREND CONTINUES...WE
MAY NEED TO START ADDING SOME SNOW CHANCES TO THE WEST FOR FRIDAY
EVENING.
THIS WEEKEND...AS THE UPPER FLOW BECOMES LESS AMPLIFIED...WE WILL
SEE A DEEP SFC LOW DROP OUT OF THE CANADIAN ARCTIC AND MOVE TOWARD
NW QUEBEC. WE WILL BE WELL WITHIN THE WARM SECTOR OF THIS SYSTEM...
THOUGH SAID WARM SECTOR IS STILL SCHEDULED TO COME THROUGH IN THE
DEAD OF NIGHT SATURDAY NIGHT. THE GEM/GFS BOTH HAVE A NICE SWATH OF
QPF WORKING DOWN WITH THE FRONT...BUT THE ECMWF CONTINUES TO BE DRY.
WITH THE GULF STILL CUT-OFF...THESE TYPES OF PATTERNS/FROPAS ARE
USUALLY DRY FOR US...SO DEFINITELY FAVOR THE DRIER ECMWF SOLUTION.
HOWEVER...WITH THE GEM/GFS IN THE BLENDING PROCEDURE USED...WE DO
HAVE POPS SPREAD ACROSS THE ENTIRE AREA SAT NIGHT...WITH THE HIGHEST
POPS OVER WI.
AFTER THIS WEEKEND...BOTH THE GFS/ECMWF SHOW THE REGION BEING DRY
UNTIL ANOTHER POWERFUL SPRING SYSTEM SHOWS UP TO WELCOME US TO APRIL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1240 PM CDT TUE MAR 24 2015
MAIN CHGS THIS AFTN WAS TO HOLD OFF ON SIGNIFICANT PRECIPITATION
UNTIL AFT 00Z. SLOWER MOVEMENT OF PRECIPITATION ACROSS NE/SD/IA
HAS LED TO A SLOWER SOLUTION ON THE ONSET OF -RA -SN AND OTHER
MIXED PRECIPITATION. IN ADDITION...HIGHER PRECIPITATION
RATES...ESPECIALLY IN TERMS OF SNOWFALL HAVE SHIFTED SLIGHTLY TO
THE SE OF OUR CWA. THEREFORE VSBYS MAY NOT BE AS LOW AS PREVIOUSLY
EXPECTED AT RNH/STC. OTHERWISE..KEPT -RASN DURING THE ONSET...WITH
A CHANGE OVER TO ALL SNOW DURING THE MID/LATE EVENING. CIGS WILL
LIKELY HOLD IN THE IFR/MVFR RANGE THRU THE PERIOD...WITH ONLY
RNH/EAU HAVING VFR INITIALLY THIS AFTN. WINDS WILL REMAIN FROM THE
SSE AND GUSTY THIS AFTN...BECOME MORE S/SW OVERNIGHT AND VEER TO
THE W/NW WEDNESDAY MORNING. HIGH CONFIDENCE IN MVFR/IFR CIGS
CONTINUING THRU 00Z...WITH LOWER CONFIDENCE ON VSBY RESTRICTION
THIS EVENING IN SNOW.
KMSP...
MAIN CHG FOR THIS TAF PERIOD IS TO HOLD OFF ON PRECIPITATION UNTIL
AFT 2Z...WITH THE BULK OF THE RAIN...CHG TO SNOW AFT 3Z. BEST CHC
OF IFR VSBY/CIGS IN SNOW WILL OCCUR IN THE 3-6Z TIME FRAME. WINDS
WILL BE GUSTY FROM THE SSE THIS AFTN...WITH WINDS DECREASING THIS
EVENING...VEERING TO THE SW BY 12Z...THEN MORE WNW/NW BY 18Z AND
BECOMING GUSTY AGAIN.
/OUTLOOK FOR KMSP/
WED NIGHT...VFR. WINDS NW 15G25 KTS EARLY.
THU...MVFR POSSIBLE EARLY. WINDS NNW 15G25 KTS.
FRI...VFR. WINDS NW 5-10 KTS BCMG SW IN THE AFTN.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 7 AM CDT
WEDNESDAY FOR MNZ077-078.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 4 AM CDT
WEDNESDAY FOR MNZ082>085-091>093.
WI...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 7 AM CDT
WEDNESDAY FOR WIZ024>028.
&&
$$
SHORT TERM...RAH
LONG TERM...MPG
AVIATION...JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
719 AM CDT TUE MAR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM CDT TUE MAR 24 2015
TOUGH FORECAST AHEAD FOR THIS AFTERNOON AND TONIGHT ON PTYPE AND
RESULTING PRECIPITATION AMOUNTS. THERE WAS QUITE THE DIFFERENCE
OUT THE GATE WITH THE 00Z RUNS BETWEEN THE NAM/GFS VERSUS THE
ECMWF/CANADIAN ON THE LAYOUT OF THE PRECIPITATION PATTERN
DEVELOPING LATER THIS AFTERNOON AND SPREADING ACROSS THE FA
TONIGHT. THE ECMWF AND CANADIAN ARE MUCH FARTHER SOUTH ON THE QPF
AXIS WITH A QUARTER INCH TONIGHT BARELY ACROSS THE SOUTHEAST PART
OF MN WHILE THE NAM/GFS HAVE THE QUARTER INCH INTO THE TWIN
CITIES. A CHECK ON RAP RUNS OVERNIGHT INDICATED A QPF PATTERN
DEVELOPING LIKE WHAT THE ECMWF AND CANADIAN ARE SHOWING. WE
BELIEVE PART OF REASON FOR THE DIFFERENCE IS THE CONVECTION
ONGOING TO OUR SOUTH THIS MORNING WITH STRONGER ACTIVITY PROGGED
FOR THIS AFTERNOON. THE NOSE OF THE 925-850MB MOISTURE TRANSPORT
WITH THE ECMWF JUST REACHES UP INTO NE IA THIS EVENING AND THEN
PASSES ACROSS SOUTHERN WI THIS EVENING. OUR INTERNAL MPX ARW-WRF
IS ALSO SHOWING THE QPF AXIS FURTHER SOUTH AS WELL. PTYPE THIS
AFTERNOON IS IN QUESTION WITH THE HRRR AND RAP SOUNDINGS
INDICATING SURFACE DEW POINTS RISING INTO THE LOWER AND MIDDLE 30S
ACROSS SOUTHERN MN WITH ALL RAIN INDICATED. THEY MAY BE TOO WARM
AS OUR MPX WRF SHOWS A CHANGE OVER TO SNOW ACROSS SOUTH CENTRAL MN
IN THE 21Z-24Z TIME FRAME ALONG WITH SOME FREEZING RAIN. HEADING
THROUGH THE EVENING...A DEEP MID LEVEL WAVE WILL PASS ACROSS IA/MO
WITH A DEFORMATION ZONE FROM NEAR KAEL TO KEAU. THIS IS THE ZONE
FOR 2 TO 4 INCHES OF SNOW ACCUMULATION TONIGHT WITH MUCH OF IT
OCCURRING BEFORE 06Z. SNOW AMOUNTS ARE LESS TO THE NORTHWEST WITH
AN INCH OR TWO IN THE TWIN CITIES WITH AROUND AN INCH AT ST.
CLOUD. BASED ON PTYPE ISSUES THIS AFTERNOON ALONG WITH THE SNOW
TONIGHT COUPLED WITH SOME MIXED SLEET AND FREEZING RAIN...WE
ISSUED A WINTER WEATHER ADVISORY FOR SOUTH CENTRAL MN BEGINNING
LATE THIS AFTERNOON WITH THE ADVISORY SPREADING NORTHEAST ACROSS
MUCH OF WEST CENTRAL WI FOR TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 410 AM CDT TUE MAR 24 2015
THE EXTENDED IS ACTUALLY LOOKING FAIRLY QUIET WITH THE MAIN
HAPPENINGS BEING THAT OF A PATTERN SHIFT...WITH A HIGHLY AMPLIFIED
PATTERN THIS WORK WEEK FLATTENING OUT AND BECOMING MORE ZONAL THIS
WEEKEND INTO NEXT WEEK. THE RESULT...TEMPS WILL REMAIN WELL BELOW
NORMAL THE REST OF THIS WORK WEEK...BUT BY THE WEEKEND...THEY WILL
REBOUND BACK TO NEAR OR EVEN A LITTLE ABOVE NORMAL.
THE LONG TERM WILL START WITH TONIGHTS TROUBLE MAKER PUSHING OUT OF
THE MPX AREA WEDNESDAY MORNING. GUIDANCE HAS CONTINUED TO PUSH WRAP
AROUND PRECIP WED/WED NIGHT FARTHER NORTH. IT IS LOOKING MORE AND
MORE LIKELY THAT THE MPX AREA WILL REMAIN DRY THIS PERIOD AS THE
WRAP AROUND MOISTURE STAYS CLOSER TO THE NRN SFC LOW THAT WILL BE
TRACKING ACROSS THE ARROWHEAD. HAVE CONTINUED THE TREND OF CUTTING
BACK POPS ON WEDNESDAY...WITH WED/WED NIGHT NOW BASICALLY DRY SOUTH
OF I-94. WHAT LOOKS MORE CERTAIN FOR WEDNESDAY ARE BREEZY
CONDITIONS. THE NAM SHOWS 3 HR PRESSURE RISES OF ABOUT 6 MB
FOLLOWING THE SFC LOW ACROSS THE ARROWHEAD...WITH 3 MB/3 HR RISES
ALL THE WAY DOWN INTO CENTRAL MN. IN ADDITION...BUFR SOUNDINGS UP AT
AXN SHOW MID CHANNEL MIX DOWN WINDS NEAR 35 KTS WITH TOP OF THE
CHANNEL WINDS AROUND 40 KTS. AS A RESULT...GAVE FORECAST WIND SPEEDS
A PRETTY GOOD BOOST FOR WEDNESDAY...WITH BORDERLINE WIND ADVY WINDS
NOW IN PLACE ACROSS WEST CENTRAL MN.
FOR THURSDAY AND FRIDAY...THE H5 FLOW BECOMES ALMOST NORTHERLY...
WHICH WILL ALLOW A 1035MB HIGH TO DROP DOWN OUT OF CANADA. WITH H85
TEMPS DOWN BETWEEN -6 TO -10C...WE WILL SEE HIGHS REMAIN IN THE 30S
BOTH DAYS...WITH SOME LOWS IN THE SINGLE DIGITS NOT OUT OF THE
QUESTION FRIDAY MORNING AS THE SFC HIGH SETTLES OVER MN AND OUR SNOW
COVER. THE ONE CHANGE SEEN WITH THE GUIDANCE THIS PERIOD IS THE
GEM/GFS/ECMWF ARE ALL SHOWING A QUICK HIT OF LIGHT PRECIP WORKING
ACROSS THE ERN DAKOTAS AND FAR WRN MN FRI/FRI NIGHT AS SHORT WAVE
ENERGY DROPPING DOWN IN THE NRLY FLOW WORKS WITH THE BAROCLINIC ZONE
ON THE BACKSIDE OF THE HIGH TO PRODUCE SOME LIGHT QPF. STILL HAVE A
DRY FORECAST OUT THAT DIRECTION...BUT IF THIS TREND CONTINUES...WE
MAY NEED TO START ADDING SOME SNOW CHANCES TO THE WEST FOR FRIDAY
EVENING.
THIS WEEKEND...AS THE UPPER FLOW BECOMES LESS AMPLIFIED...WE WILL
SEE A DEEP SFC LOW DROP OUT OF THE CANADIAN ARCTIC AND MOVE TOWARD
NW QUEBEC. WE WILL BE WELL WITHIN THE WARM SECTOR OF THIS SYSTEM...
THOUGH SAID WARM SECTOR IS STILL SCHEDULED TO COME THROUGH IN THE
DEAD OF NIGHT SATURDAY NIGHT. THE GEM/GFS BOTH HAVE A NICE SWATH OF
QPF WORKING DOWN WITH THE FRONT...BUT THE ECMWF CONTINUES TO BE DRY.
WITH THE GULF STILL CUT-OFF...THESE TYPES OF PATTERNS/FROPAS ARE
USUALLY DRY FOR US...SO DEFINITELY FAVOR THE DRIER ECMWF SOLUTION.
HOWEVER...WITH THE GEM/GFS IN THE BLENDING PROCEDURE USED...WE DO
HAVE POPS SPREAD ACROSS THE ENTIRE AREA SAT NIGHT...WITH THE HIGHEST
POPS OVER WI.
AFTER THIS WEEKEND...BOTH THE GFS/ECMWF SHOW THE REGION BEING DRY
UNTIL ANOTHER POWERFUL SPRING SYSTEM SHOWS UP TO WELCOME US TO APRIL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 719 AM CDT TUE MAR 24 2015
IFR/LOW MVFR CEILINGS COVER THE MN TAF SITES THIS AM. WE MAY
STRUGGLE FOR MUCH IMPROVEMENT IN THE MN RIVER VALLEY TODAY WITH A
MOIST SOUTHEAST LOW LEVEL FLOW WITH CEILINGS KEPT IN PLACE. LOW
MVFR CEILINGS MAY EVEN SNEAK BACK IN AT KRNH AND KEAU FOR A TIME
THIS MORNING ALTHOUGH CONFIDENCE IS NOT HIGH. SEVERAL RUNS OF THE
HRRR STILL SHOW THAT ANY MVFR CEILINGS FROM KMSP WILL MOVE OUT
EARLY THIS AFTERNOON. PRECIPITATION TRENDS HAVE CHANGED SOME SINCE
THE LAST TAF ISSUANCE. SHORT TERM SOLUTIONS ARE INDICATING A
SLOWER ONSET FOR THE TWIN CITIES ON EAST AND THIS WAS INCORPORATED
INTO THE NEW SET. A MIX OF RAIN AND SNOW SHOULD SWITCH OVER TO
SNOW FROM THE TWIN CITIES ON EAST AND SOUTH THIS EVENING WITH A
BAND OF MODERATE SNOW TO THE SOUTHEAST OF THE TWIN CITIES TO KEAU.
DRIER MID LEVEL AIR WILL WORK IN FROM THE SOUTHWEST LATE IN THE
NIGHT...ENDING PRECIP TO THE WEST AND SOUTH OF THE TWIN CITIES. SE
WINDS GUSTING 15-20 KNOTS TODAY VEERING WESTERLY LATE TONIGHT.
KMSP...LOW MVFR CEILINGS ARE BACK BUT EXPECT A BREAK OUT TO VFR
THIS AFTERNOON BEFORE DETERIORATING BACK DOWN TO LOW MVFR/IFR
TONIGHT. RAIN/SNOW SPREADING IN AFTER 25/00Z CHANGING TO ALL SNOW
BY 03Z AND CONTINUING UNTIL ABOUT 09Z. SNOWFALL RATES ARE EXPECTED
TO BE HIGHEST FROM 03Z-06Z WITH AROUND A 1/2 INCH PER HOUR.
/OUTLOOK FOR KMSP/
WED...MVFR. WINDS W 15G25 KTS.
THU...MVFR AND -SN POSSIBLE EARLY. WINDS NNW 15G25 KTS.
FRI...VFR. WINDS NW 5-10 KTS BCMG SW IN THE AFTN.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM CDT
WEDNESDAY FOR MNZ082>085-091>093.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 4 AM CDT
WEDNESDAY FOR MNZ077-078.
WI...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM CDT
WEDNESDAY FOR WIZ024>028.
&&
$$
SHORT TERM...RAH
LONG TERM...MPG
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
410 AM CDT TUE MAR 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 410 AM CDT TUE MAR 24 2015
TOUGH FORECAST AHEAD FOR THIS AFTERNOON AND TONIGHT ON PTYPE AND
RESULTING PRECIPITATION AMOUNTS. THERE WAS QUITE THE DIFFERENCE
OUT THE GATE WITH THE 00Z RUNS BETWEEN THE NAM/GFS VERSUS THE
ECMWF/CANADIAN ON THE LAYOUT OF THE PRECIPITATION PATTERN
DEVELOPING LATER THIS AFTERNOON AND SPREADING ACROSS THE FA
TONIGHT. THE ECMWF AND CANADIAN ARE MUCH FARTHER SOUTH ON THE QPF
AXIS WITH A QUARTER INCH TONIGHT BARELY ACROSS THE SOUTHEAST PART
OF MN WHILE THE NAM/GFS HAVE THE QUARTER INCH INTO THE TWIN
CITIES. A CHECK ON RAP RUNS OVERNIGHT INDICATED A QPF PATTERN
DEVELOPING LIKE WHAT THE ECMWF AND CANADIAN ARE SHOWING. WE
BELIEVE PART OF REASON FOR THE DIFFERENCE IS THE CONVECTION
ONGOING TO OUR SOUTH THIS MORNING WITH STRONGER ACTIVITY PROGGED
FOR THIS AFTERNOON. THE NOSE OF THE 925-850MB MOISTURE TRANSPORT
WITH THE ECMWF JUST REACHES UP INTO NE IA THIS EVENING AND THEN
PASSES ACROSS SOUTHERN WI THIS EVENING. OUR INTERNAL MPX ARW-WRF
IS ALSO SHOWING THE QPF AXIS FURTHER SOUTH AS WELL. PTYPE THIS
AFTERNOON IS IN QUESTION WITH THE HRRR AND RAP SOUNDINGS
INDICATING SURFACE DEW POINTS RISING INTO THE LOWER AND MIDDLE 30S
ACROSS SOUTHERN MN WITH ALL RAIN INDICATED. THEY MAY BE TOO WARM
AS OUR MPX WRF SHOWS A CHANGE OVER TO SNOW ACROSS SOUTH CENTRAL MN
IN THE 21Z-24Z TIME FRAME ALONG WITH SOME FREEZING RAIN. HEADING
THROUGH THE EVENING...A DEEP MID LEVEL WAVE WILL PASS ACROSS IA/MO
WITH A DEFORMATION ZONE FROM NEAR KAEL TO KEAU. THIS IS THE ZONE
FOR 2 TO 4 INCHES OF SNOW ACCUMULATION TONIGHT WITH MUCH OF IT
OCCURRING BEFORE 06Z. SNOW AMOUNTS ARE LESS TO THE NORTHWEST WITH
AN INCH OR TWO IN THE TWIN CITIES WITH AROUND AN INCH AT ST.
CLOUD. BASED ON PTYPE ISSUES THIS AFTERNOON ALONG WITH THE SNOW
TONIGHT COUPLED WITH SOME MIXED SLEET AND FREEZING RAIN...WE
ISSUED A WINTER WEATHER ADVISORY FOR SOUTH CENTRAL MN BEGINNING
LATE THIS AFTERNOON WITH THE ADVISORY SPREADING NORTHEAST ACROSS
MUCH OF WEST CENTRAL WI FOR TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 410 AM CDT TUE MAR 24 2015
THE EXTENDED IS ACTUALLY LOOKING FAIRLY QUIET WITH THE MAIN
HAPPENINGS BEING THAT OF A PATTERN SHIFT...WITH A HIGHLY AMPLIFIED
PATTERN THIS WORK WEEK FLATTENING OUT AND BECOMING MORE ZONAL THIS
WEEKEND INTO NEXT WEEK. THE RESULT...TEMPS WILL REMAIN WELL BELOW
NORMAL THE REST OF THIS WORK WEEK...BUT BY THE WEEKEND...THEY WILL
REBOUND BACK TO NEAR OR EVEN A LITTLE ABOVE NORMAL.
THE LONG TERM WILL START WITH TONIGHTS TROUBLE MAKER PUSHING OUT OF
THE MPX AREA WEDNESDAY MORNING. GUIDANCE HAS CONTINUED TO PUSH WRAP
AROUND PRECIP WED/WED NIGHT FARTHER NORTH. IT IS LOOKING MORE AND
MORE LIKELY THAT THE MPX AREA WILL REMAIN DRY THIS PERIOD AS THE
WRAP AROUND MOISTURE STAYS CLOSER TO THE NRN SFC LOW THAT WILL BE
TRACKING ACROSS THE ARROWHEAD. HAVE CONTINUED THE TREND OF CUTTING
BACK POPS ON WEDNESDAY...WITH WED/WED NIGHT NOW BASICALLY DRY SOUTH
OF I-94. WHAT LOOKS MORE CERTAIN FOR WEDNESDAY ARE BREEZY
CONDITIONS. THE NAM SHOWS 3 HR PRESSURE RISES OF ABOUT 6 MB
FOLLOWING THE SFC LOW ACROSS THE ARROWHEAD...WITH 3 MB/3 HR RISES
ALL THE WAY DOWN INTO CENTRAL MN. IN ADDITION...BUFR SOUNDINGS UP AT
AXN SHOW MID CHANNEL MIX DOWN WINDS NEAR 35 KTS WITH TOP OF THE
CHANNEL WINDS AROUND 40 KTS. AS A RESULT...GAVE FORECAST WIND SPEEDS
A PRETTY GOOD BOOST FOR WEDNESDAY...WITH BORDERLINE WIND ADVY WINDS
NOW IN PLACE ACROSS WEST CENTRAL MN.
FOR THURSDAY AND FRIDAY...THE H5 FLOW BECOMES ALMOST NORTHERLY...
WHICH WILL ALLOW A 1035MB HIGH TO DROP DOWN OUT OF CANADA. WITH H85
TEMPS DOWN BETWEEN -6 TO -10C...WE WILL SEE HIGHS REMAIN IN THE 30S
BOTH DAYS...WITH SOME LOWS IN THE SINGLE DIGITS NOT OUT OF THE
QUESTION FRIDAY MORNING AS THE SFC HIGH SETTLES OVER MN AND OUR SNOW
COVER. THE ONE CHANGE SEEN WITH THE GUIDANCE THIS PERIOD IS THE
GEM/GFS/ECMWF ARE ALL SHOWING A QUICK HIT OF LIGHT PRECIP WORKING
ACROSS THE ERN DAKOTAS AND FAR WRN MN FRI/FRI NIGHT AS SHORT WAVE
ENERGY DROPPING DOWN IN THE NRLY FLOW WORKS WITH THE BAROCLINIC ZONE
ON THE BACKSIDE OF THE HIGH TO PRODUCE SOME LIGHT QPF. STILL HAVE A
DRY FORECAST OUT THAT DIRECTION...BUT IF THIS TREND CONTINUES...WE
MAY NEED TO START ADDING SOME SNOW CHANCES TO THE WEST FOR FRIDAY
EVENING.
THIS WEEKEND...AS THE UPPER FLOW BECOMES LESS AMPLIFIED...WE WILL
SEE A DEEP SFC LOW DROP OUT OF THE CANADIAN ARCTIC AND MOVE TOWARD
NW QUEBEC. WE WILL BE WELL WITHIN THE WARM SECTOR OF THIS SYSTEM...
THOUGH SAID WARM SECTOR IS STILL SCHEDULED TO COME THROUGH IN THE
DEAD OF NIGHT SATURDAY NIGHT. THE GEM/GFS BOTH HAVE A NICE SWATH OF
QPF WORKING DOWN WITH THE FRONT...BUT THE ECMWF CONTINUES TO BE DRY.
WITH THE GULF STILL CUT-OFF...THESE TYPES OF PATTERNS/FROPAS ARE
USUALLY DRY FOR US...SO DEFINITELY FAVOR THE DRIER ECMWF SOLUTION.
HOWEVER...WITH THE GEM/GFS IN THE BLENDING PROCEDURE USED...WE DO
HAVE POPS SPREAD ACROSS THE ENTIRE AREA SAT NIGHT...WITH THE HIGHEST
POPS OVER WI.
AFTER THIS WEEKEND...BOTH THE GFS/ECMWF SHOW THE REGION BEING DRY
UNTIL ANOTHER POWERFUL SPRING SYSTEM SHOWS UP TO WELCOME US TO APRIL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1003 CDT MON MAR 23 2015
CIGS HAVE NOT DECREASED SINCE SUNSET...BUT MVFR CIGS REMAIN IN
PLACE IN SOUTHERN MN AS LOW LEVEL MOISTURE REMAINS IN PLACE OVER
THE SNOWPACK. THE EASTERN EDGE OF THIS CLOUD DECK HAS BEEN SLOWLY
ERODING...AND VFR CONDITIONS NOW LOOK LIKELY OVERNIGHT AT EAU AND
POSSIBLE AT RNH. WHERE LOW CLOUDS REMAIN...CIGS WILL GRADUALLY
IMPROVE TUESDAY MORNING WITH VFR RETURNING...BUT AREAS THAT HAVE
SNOW COVER MAY BE SLOWER TO IMPROVE. WINDS WILL REMAIN
SOUTHEASTERLY AND INCREASE TO 10-15 KTS DURING THE AFTERNOON. SNOW
WILL DEVELOP OVER SW MN TUESDAY AFTERNOON AND MOVE INTO THE REST
OF OUR AREA DURING THE EVENING...RESULTING IN IFR CONDITIONS
THROUGH THE END OF THE PERIOD.
KMSP...MVFR CIGS WILL LIKELY CONTINUE OVERNIGHT AS LOW CLOUDS ARE
EXPECTED TO PERSIST OVER THE TERMINAL. CIGS SHOULD IMPROVE
TUESDAY MORNING...WITH VFR LIKELY RETURNING BY TUESDAY AFTERNOON.
PRECIPITATION IS EXPECTED TO RETURN AROUND 00Z TUESDAY
EVENING...POSSIBLY STARTING OUT AS A MIX OF RAIN AND SNOW BUT
QUICKLY CHANGING TO SNOW. IFR CONDITIONS ARE LIKELY TO RETURN
TUESDAY EVENING ONCE THE SNOW BEGINS.
/OUTLOOK FOR KMSP/
TUESDAY NIGHT...MVFR/IFR WITH -RA/-SN. WINDS SE 10-15 KTS.
WED...MVFR/IFR WITH -RA/-SN. WINDS W 15G25 KTS.
THU...MVFR AND -SN POSSIBLE EARLY. WINDS NNW 15G20 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 4 AM CDT
WEDNESDAY FOR MNZ082>085-091>093.
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 4 AM CDT
WEDNESDAY FOR MNZ077-078.
WI...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM CDT
WEDNESDAY FOR WIZ024>028.
&&
$$
SHORT TERM...RAH
LONG TERM...MPG
AVIATION...ADL
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
223 PM CDT Tue Mar 24 2015
.SHORT TERM...(Tonight)
Issued at 141 PM CDT TUE MAR 24 2015
In the near term severe weather chances are the obvious concern.
Sfc low over just north of KEQA in se KS as of 18z will progress
east with a trailing dry line/sfc trough moving into the eastern
cwfa by 21z. Cap in place now, but a combo of daytime warming,
mid level cooling with increased lift and a narrow corridor of
low level moisture advection is expected to weaken the cap over
the next couple of hours allowing sfc convergence near the
boundary to initiate storms. Latest high res guidance (HRRR, among
others) have been consistent with developing convection by 21z-22z
close to the se KS/sw Mo state line. While model dew points may be
a bit bullish, still looks like a good bet with a corridor/broken
line of convection moving quickly w-e through the cwfa late this
afternoon and early this evening.
ML CAPE values of 1000-2000 j/kg indicated by the HRRR in a
narrow corridor along the sfc trough coupled with more than
adequate deep level 0-6 km bulk shear of around 40-50 kts and 0-3
km helicity of 200-300 m2/s2 will allow rotating updrafts to
develop with stronger convection. With somewhat limited low level
moisture/higher cloud bases, the main storm hazard will be hail
given steep mid level lapse rates. Localized severe winds also a
possibility. The tornado risk would appear low (but not zero),
again given the lack of deeper low level moisture and a veered low
level sfc wind profile along the sfc trough.
The severe window should be small time-wise. Storms should quickly
move east through the cwfa this evening, weakening late with more
limited instability.
.LONG TERM...(Wednesday through Tuesday)
Issued at 215 PM CDT TUE MAR 24 2015
A second shortwave, more positively tilted, will make it`s way
through the region Wed with a cold frontal passage expected.
Weather hazards may include some severe wx and a risk of excessive
rainfall over the southeast half of the cwfa.
Storms are expected to re-initiate in the afternoon gradually
coalescing into line segments, potentially training, over parts of
southern mo late in the afternoon and evening. Again the main
storm concerns will be during the initialization phase with hail
and winds with MLCAPE values of 1000-2000 j/kg over far southern
MO with abundant deep layer shear. With the potential for training
storms in the evening, some guidance is hitting rainfall amounts
hard (particularly the 12z ECMWF, NAM, GFS) in south central MO
where recent heavy rain and flooding occurred. Will be looking at
a possible flood watch for portions of the area, but still
ironing out the details.
Unseasonable cold is expected late in the week as a deep upper
level trough develops over much of the eastern CONUS. Nighttime
temperatures will drop below freezing late in the week. Small
scale shortwaves moving se through the region may kick off some
light/brief periods of rain/snow at times. A modest warming trend
develops late in the extended period.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 121 PM CDT TUE MAR 24 2015
Pilots flying in and out of
the southwest Missouri airports need to monitor radar closely late
this afternoon and this evening.
Severe thunderstorms are expected to develop near the Kansas and
the Missouri state line, and move east through much of southern
and central Missouri.
Large hail appears to be the main severe weather risk with these
storms.
By 8 or 9pm, this activity will shift east of the southwest
Missouri airports, allowing for VFR conditions the rest of the
night.
Look for surface winds to become light and variable by mid
evening.
Safe Travels.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...DSA
LONG TERM...DSA
AVIATION...Cramer
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
146 PM CDT Tue Mar 24 2015
.MESOSCALE DISCUSSION...
Issued at 141 PM CDT TUE MAR 24 2015
In the near term severe weather chances are the obvious concern.
Sfc low over just north of KEQA in se KS as of 18z will progress
east with a trailing dry line/sfc trough moving into the eastern
cwfa by 21z. Cap in place now, but a combo of daytime warming,
mid level cooling with increased lift and a narrow corridor of
low level moisture advection is expected to weaken the cap over
the next couple of hours allowing sfc convergence near the
boundary to initiate storms. Latest high res guidance (HRRR, among
others) have been consistent with developing convection by 21z-22z
close to the se KS/sw Mo state line. While model dew points may be
a bit bullish, still looks like a good bet with a corridor/broken
line of convection moving quickly w-e through the cwfa late this
afternoon and early this evening.
ML CAPE values of 1000-2000 j/kg indicated by the HRRR in a
narrow corridor along the sfc trough coupled with more than
adequate deep level 0-6 km bulk shear of around 40-50 kts and 0-3
km helicity of 200-300 m2/s2 will allow rotating updrafts to
develop with stronger convection. With somewhat limited low level
moisture/higher cloud bases, the main storm hazard will be hail
given steep mid level lapse rates. Localized severe winds also a
possibility. The tornado risk would appear low (but not zero),
again given the lack of deeper low level moisture and a veered low
level sfc wind profile along the sfc trough.
The severe window should be small time-wise. Storms should quickly
move east through the cwfa this evening, weakening late with more
limited instability.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
MESOSCALE...DSA
SHORT TERM...Gagan
LONG TERM...Gagan
AVIATION...Cramer
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
957 AM MDT TUE MAR 24 2015
.UPDATE...
UPDATED FORECAST TO FOLLOW RADAR TRENDS WITH PRECIPITATION
DECREASING OVER THE EAST WITH BOWMAN RADAR SHOWING WRAP AROUND
BAND PULLING OUT OF BAKER. BAKER HAD SNOW CHANGE BACK OVER TO
RAIN AND EVEN THE BACK EDGE OF THE LOW CLOUDS SHOULD BE
PROGRESSIVE THROUGH THE AREA. LOWERED CLOUD COVER IN CENTRAL ZONES
AS VISIBLE SATELLITE SHOWS A GOOD BREAK AHEAD OF THE
DESTABILIZATION FROM THE SYSTEM MOVING THROUGH IDAHO. DIURNAL
HEATING AND COOLING ALOFT WILL SUPPORT INCREASING CONVECTIVE
ACTIVITY THROUGH THE AFTERNOON WITH A SURFACE BOUNDARY SLIDING
THROUGH THE REGION IN THE EVENING. WHEN THIS BOUNDARY REACHES THE
FOOTHILLS AND MOUNTAINS IT WILL BECOME THE FOCUS FOR HEAVY SNOW
SHOWERS AND CURRENT HIGHLIGHTS LOOK GOOD. FURTHER NORTH ALONG THE
YELLOWSTONE RIVER VALLEY WILL SEE A RAIN SNOW MIX UNTIL MIDNIGHT
THOUGH RUC INDICATES SOME LOCAL FREEZING LEVEL LOWERINGS DUE TO
THE CONVECTIVE ACTIVITY. WITH WARM GROUND AND SHORT WIND FOR
SNOWFALL DO NOT EXPECT MUCH IN THE WAY OF ACCUMULATIONS LOWER
ELEVATIONS. BORSUM
&&
.SHORT TERM...VALID FOR TDY AND WED...
AN UNSETTLED WEATHER PATTERN IS EXPECTED TODAY AND WEDNESDAY WITH
THE HIGHLIGHT LIKELY BEING HEAVY SNOW SHOWERS IN THE BEARTOOTH AND
ABSAROKA MOUNTAINS AND THE RED LODGE FOOTHILLS...MAINLY TONIGHT.
TODAY...WRAP-AROUND MOISTURE IN THE FORM OF RAIN AND POSSIBLY EVEN
A MIX WITH SNOW WILL LINGER IN FAR SOUTHEASTERN MT...ESPECIALLY IN
THE BAKER AREA...THIS MORNING. OVERNIGHT RADAR AND MODEL DATA BOTH
SUGGEST A SLOWER AND DEEPER LOW- TO MID-LEVEL LOW MOVING NORTHEAST
INTO NORTH DAKOTA THIS MORNING IN SUPPORT OF THAT PRECIPITATION. A
COOLER AND BREEZY TO WINDY DAY IS EXPECTED IN THE WAKE OF THAT LOW
WITH CYCLONIC FLOW SUPPORTING LOW POPS MOST EVERYWHERE. HOWEVER...
FORECAST SOUNDINGS IN SOUTHEASTERN MT ARE NOT THAT UNSTABLE AND WE
DID NOT SEE MUCH SUPPORT FOR EVEN SHALLOW CONVECTION IN THE 00 UTC
HIGH-RESOLUTION MODEL OUTPUT...SO SLIGHT-CHANCE POPS MIGHT EVEN BE
TOO MUCH IN SOUTHEASTERN MT THIS AFTERNOON. BACK FURTHER WEST...WE
EXPECT INCREASING SHOWER ACTIVITY AFTER 18 UTC AS ANOTHER MID- AND
UPPER-LEVEL SHORTWAVE TROUGH BEGINS AFFECTING THE AREA. WE BEGAN A
WINTER STORM WARNING FOR THE BEARTOOTH/ABSAROKA RANGES AT NOON MDT
/18 UTC/ AS THAT WAVE APPROACHES AS SNOW SHOWERS SHOULD PICK UP IN
EARNEST AT THE HIGHER ELEVATIONS THIS AFTERNOON.
TONIGHT...A WEAK SOUTHWARD-MOVING FRONTAL PUSH IS EXPECTED AS THAT
SHORTWAVE TROUGH DROPS ACROSS WY. THAT WILL TURN LOW-LEVEL FLOW TO
A MORE NORTHERLY AND UPSLOPE TRAJECTORY AND THAT WILL COMBINE WITH
THE CYCLONIC FLOW ALOFT AND STEEP MID-LEVEL LAPSE RATES OF 7 C/KM
TO PRODUCE HEALTHY PRECIPITATION OVER AND NEAR THE HIGHER TERRAIN
OF SOUTH CENTRAL MT AND NORTH CENTRAL WY. THIS TYPE OF LARGE-SCALE
PATTERN FAVORS HEAVY SNOW ON THE NORTH SLOPES OF THE BEARTOOTH AND
ABSAROKAS AND IN THE FOOTHILLS AT RED LODGE...AND USING A BLEND OF
00 UTC HIGH-RESOLUTION WRF-NMM AND WRF-ARW MODEL DATA WITH A DASH
OF INPUT FROM A LOCALLY-RUN WRF-NMM PRODUCED AT NWS RIVERTON GAVE
LIQUID-EQUIVALENT MOISTURE TOTALS OF 0.70 TO 1.00 ON SLOPES WHICH
ARE FAVORED BY THE EXPECTED WIND DIRECTIONS. IT/S A BIT UNCLEAR AS
TO WHEN RAIN WILL CHANGE OVER TO SNOW DOWN TO RED LODGE...BUT NONE
OF THE MODEL GUIDANCE SUGGESTS IT WON/T DO SO BY LATE EVENING. OUR
FORECAST IS THUS A RELATIVELY HIGH-CONFIDENCE ONE IN SUPPORT OF 8
TO 14 INCHES OF SNOW OVER THE MOUNTAINS AND HIGHER...NORTH-FACING
SLOPES AND 5 TO LOCALLY 10 INCHES AROUND RED LODGE. WE THUS ISSUED
A WINTER STORM WARNING FOR THE RED LODGE FOOTHILLS AS WELL BETWEEN
6 PM MDT THIS EVENING AND 9 AM MDT WEDNESDAY...WHEN WE ALSO ENDED
THE WARNING FOR THE MOUNTAINS. THE HIGH-RESOLUTION MODEL GUIDANCE
WE USED TO BUILD THE FORECAST SUGGESTED LOWER TOTALS JUST BENEATH
ADVISORY-LEVEL CRITERIA IN THE BEARTOOTH FOOTHILLS LIKE AT MCLEOD
AND OVER THE NORTHEASTERN BIGHORN MOUNTAINS...AND SO CONFIDENCE IN
GETTING HEADLINE-WORTHY SNOW WASN/T HIGH ENOUGH FOR US TO ISSUE A
WINTER WEATHER ADVISORY IN THOSE LOCATIONS JUST YET. THERE WILL BE
SNOW IN THOSE PLACES THOUGH AND A LATER FORECAST MAY NEED TO ADD
IN SOME ADDITIONAL HEADLINES THERE.
OTHERWISE...WE ALSO HAVE CHANCE-STYLE POPS ELSEWHERE IN THE LOWER
ELEVATIONS OF SOUTH CENTRAL MT AND NORTH CENTRAL WY TONIGHT AS
WELL IN RESPECT TO THE SAME SCENARIO...ALBEIT WITH WEAKER FORCING
IN SUPPORT OF ONLY LIGHT MOISTURE TOTALS IN SPOTS LIKE BILLINGS.
WEDNESDAY...CYCLONIC FLOW WILL CONTINUE AND SO WILL SOME CHANCE
OF SHOWERS IN MOST AREAS. IT WILL ALSO STAY RELATIVELY COOL WITH
HIGHS ONLY IN THE 40S TO LOWER 50S F. SCHULTZ
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
MOIST NW FLOW WILL CONTINUE OVER THE REGION THURSDAY BUT LATEST
TRENDS ARE TO KEEP THE SFC TROF A BIT EAST OF BILLINGS AS RIDGE
BEGINS TO BUILD IN FROM THE WEST. THIS WILL RESULT IN WARMER AND
DRIER CONDITIONS IN OUR WEST HALF...WITH MUCH BETTER CHANCE OF
SHOWERS TO THE EAST ESPECIALLY AS WEAK BACKDOOR COOLING INCREASES
LOW LEVEL BAROCLINICITY. EXPECTING SOME MORE SNOW ACCUMULATION
OVER THE NW FLOW FAVORED BIGHORN MTNS...BUT LOWER ELEVATION
SNOWFALL SHOULD BE MINIMAL OR NONEXISTENT DUE TO MILD SFC TEMPS.
IT IS ALSO POSSIBLE THAT PARTS OF OUR EAST COULD MIX WITH A LITTLE
LIGHT FREEZING RAIN EITHER EARLY THURSDAY MORNING OR THURSDAY
NIGHT BEFORE PCPN ENDS AS WARM ADVECTION OVERRUNS THE
AFOREMENTIONED BACKDOOR COOL FRONT. AS FOR TEMPS...HAVE RAISED
THURSDAY HIGHS AND THURSDAY NIGHT LOWS SIGNIFICANTLY ESPECIALLY
FROM BILLINGS WEST. SHOULD SEE HIGHS ON THURSDAY BACK NEAR 60F OUT
WEST...AND ONLY IN THE 40S ALONG THE DAKOTAS BORDER.
UPPER RIDGE SHIFTS EAST ALLOWING FOR MUCH WARMER TEMPERATURES
FRIDAY AND SATURDAY. GIVEN H5 HEIGHTS INTO THE 570S AND 700MB
TEMPS ABOVE 0C WE WILL SEE TEMPS GET BACK TO THE UPPER 60S AND
70S. A BREAK DOWN OF THIS RIDGE IS IN STORE FOR SATURDAY BUT THERE
ARE TIMING ISSUES WHICH WILL SIGNIFICANTLY IMPACT HOW WARM IT MAY
GET ON SATURDAY. A QUICKER FRONTAL PASSAGE WILL OBVIOUSLY BEGIN A
COOL DOWN ON SATURDAY...BUT IF THE SLOWER ECMWF VERIFIES WE COULD
BE LOOKING AT SOME MID TO UPPER 70S IN A STRONG DOWNSLOPE AND
PREFRONTAL REGIME AHEAD OF A FROPA EITHER SATURDAY AFTERNOON OR
EVENING. A FEW HOURS COULD MAKE A BIG DIFFERENCE HERE.
SHOULD SEE AT LEAST SOME LIGHT SHOWER ACTIVITY ASSOCIATED WITH
WEAK WEEKEND CLIPPER...ALONG WITH A MODEST COOL DOWN INTO SUNDAY.
THIS IS EXPECTED TO BE A WEAK SYSTEM AND HEIGHTS REMAIN NEAR
570DAM ON SUNDAY...SO IMPACTS WILL BE MINIMAL. COULD SEE SOME
RESIDUAL SHOWERS OVER THE MOUNTAINS MONDAY BUT OTHERWISE MODEL
CONSENSUS IS FOR BROAD UPPER RIDGING. TEMPS WILL REMAIN ABOVE
NORMAL SUNDAY/MONDAY.
LOOKING A BIT FURTHER AHEAD...THERE IS POTENTIAL FOR A STRONGER
TROF AND INCREASED PCPN CHANCES BY NEXT TUESDAY/WEDNESDAY...BUT
PLENTY OF MODEL SPREAD EXISTS BOTH WITH THIS FEATURE AND FLOW IN
THE NORTHEAST PACIFIC. STAY TUNED.
JKL
&&
.AVIATION...
LIGHT PRECIPITATION AND IFR CONDITIONS WILL SLOWLY MOVE OUT OF
KBHK THIS MORNING. CONDITIONS SHOULD RISE TO VFR BY EARLY
AFTERNOON. THE REST OF THE AREA WILL HAVE VFR FLYING CONDITIONS.
SHOWERS WILL DEVELOP THIS AFTERNOON...ESPECIALLY IN THE MOUNTAINS.
SOME OF THE SHOWERS COULD CAUSE LOCAL MVFR CONDITIONS. THE
MOUNTAINS WILL BE OBSCURED. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY WED THU FRI SAT SUN MON
-------------------------------------------------------
BIL 055 030/052 038/060 040/071 048/076 040/065 041/070
4/W 53/W 32/W 10/B 02/W 22/W 11/B
LVM 048 029/049 033/060 040/071 048/071 038/065 040/068
5/W 83/W 22/W 10/B 02/W 22/W 21/B
HDN 059 028/053 032/059 032/073 040/078 035/066 035/072
3/W 53/W 32/W 10/B 02/W 22/W 11/B
MLS 055 027/048 030/050 033/067 040/075 034/061 037/068
2/W 11/B 22/W 10/B 02/W 21/B 11/U
4BQ 057 026/048 030/050 029/068 040/077 035/064 036/070
2/W 11/B 24/W 20/B 02/W 21/B 11/B
BHK 046 024/042 024/045 027/061 036/073 032/059 033/065
7/W 11/B 22/W 21/E 02/W 21/U 11/U
SHR 054 027/046 030/053 032/068 039/076 036/065 035/070
3/W 54/W 34/W 20/B 02/W 22/W 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO 9 AM
MDT WEDNESDAY FOR ZONE 56.
WINTER STORM WARNING IN EFFECT UNTIL 9 AM MDT WEDNESDAY FOR
ZONE 67.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
122 PM CDT TUE MAR 24 2015
.SYNOPSIS...
ISSUED AT 335 AM CDT TUE MAR 24 2015
AT 08Z...TWO MAIN AREAS OF SURFACE LOW PRESSURE EXIST. ONE
LOCATED IN FAR ERN WY WHILE THE OTHER IN THE OKLA PNHDL. VERY
LITTLE CURRENTLY ON THE KLBF RADAR EXCEPT FOR A NARROW BAND OF
SHOWERS AND SPRINKLES FROM SWRN CUSTER COUNTY INTO SERN LINCOLN
AND FRONTIER COUNTY. SCATTERED SHOWERS AND THUNDERSTORMS
CURRENTLY EXTEND FROM PARTS OF NCTRL KS INTO SCTRL AND SERN NEBR
AND NWRN MISSOURI WITH JUST OVER 200 LIGHTNING STRIKES THE PAST
HOUR.
&&
.UPDATE...
ISSUED AT 1016 AM CDT TUE MAR 24 2015
FORECAST WAS UPDATED DUE TO RADAR AND CLOUD TRENDS FOR THIS
MORNING AS RAIN SHOWERS OVER NORTH CENTRAL NEBRASKA ARE
PROGRESSING EAST AND SHOULD BE MOSTLY OUT OF THE FORECAST AREA
BY EARLY AFTERNOON. WITH LOW PRESSURE CENTERED OVER SOUTHWEST
NORTH DAKOTA AT MID MORNING...A SURFACE TROUGH WAS LOCATED THROUGH
WESTERN SOUTH DAKOTA AND DOWN THROUGH THE EASTERN NEBRASKA
PANHANDLE. THIS TROUGH WILL MAKE ITS WAY EAST TODAY AND AS CLOUDS
CLEAR BEHIND THE ONGOING PRECIPITATION...WARMING AHEAD OF THE
TROUGH WILL ALLOW SOME VERY WEAK INSTABILITY TO BUILD ROUGHLY FROM
NORTH CENTRAL INTO CENTRAL NEBRASKA THIS AFTERNOON. IT WILL BE
WEAK WITH THE RAP SHOWING 100-200J/KG OF MUCAPE. THIS MAY BE
ENOUGH FOR SOME LIGHT RAIN SHOWERS TO DEVELOP ALONG THE TROUGH
THIS AFTERNOON SO DID ADD IN A SLIGHT CHANCE FOR RAIN SHOWERS IN
THOSE AREAS. NO MENTION OF THUNDER AT THE TIME AS THE INSTABILITY
LOOKS TOO WEAK BUT WILL KEEP AN EYE ON THINGS INTO THE AFTERNOON.
RED FLAG WARNING FOR SOUTHWEST NEBRASKA REMAINS TO LOOK ON TRACK
AS DRY AIR IS EXPECTED TO PUSH INTO THE AREA WITH WINDS INCREASING
AS THE BOUNDARY LAYER BECOMES FULLY MIXED TO AROUND 700MB THIS
AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT TUE MAR 24 2015
TODAY...THE UPPER TROUGH CURRENTLY ACROSS WRN SD AND THE WRN
PNHDL WILL PROGRESS EASTWARD TODAY. SHOWERS WILL DEVELOP TO THE
EAT OF THIS TROUGH...MAINLY EAST OF A BASSETT THROUGH BROKEN BOW
LINE BY 15Z. LIKELY POPS ACROSS PORTIONS OF
BOYD...HOLT...GARFIELD AND WHEELER COUNTY. THIS IN GOOD AGREEMENT
BY LATEST RAP13...HRRR AND 06Z NAM MODELS. A FEW SHOWERS MAY ALSO
DEVELOP ACROSS FAR NRN NEBR THIS AFTERNOON WITHIN AREA OF A VORT
MAX MOVING THROUGH THAT AREA. HIGHS TODAY REMAIN NEAR PREVIOUS
FORECAST REACHING THE LOW TO MID 60S MOST AREAS. EXCEPTION WILL
BE IN FAR EASTERN AREAS WHERE CONSIDERABLE CLOUDINESS AND SHOWERS
TO HOLD DOWN HIGHS TO THE MID 50S. A FAIRLY STRONG PV ANOMALY
EMERGING FROM NERN CO INTO SWRN NEBR AND NWRN KS THIS MORNING
LOOKS FAVORABLE FOR MIXING DOWN STRONGER WINDS TO THE SURFACE
ACROSS THE SERN PNHDL AND SWRN NEBR INTO THIS AFTERNOON.
NORTHWEST WINDS IN THESE AREAS ARE FORECAST TO INCREASE TO 25 TO
35 MPH THIS AFTERNOON. EXPOSED WHEAT FIELDS AND OTHER TILLED
GROUND WILL BE SUSCEPTIBLE TO BLOWING DUST...AND ADDED AREAS OF
BLOWING DUST THIS AFTERNOON. IN ADDITION...CRITICAL FIRE WEATHER
CONDITIONS MET IN PORTIONS OF SWRN NEBR WITH DETAILS HIGHLIGHTED
IN THE FIRE WEATHER DISCUSSION.
TONIGHT...INCREASING CLOUDINESS ACROSS WRN NEBR AS A DISTURBANCE
IN NERN WY WILL DROP SOUTHEAST INTO NRN NEBR AND FAR SRN SD WITH
A SLIGHT CHANCE FOR SHOWERS...WHICH IS SIMILAR TO PREVIOUS
FORECAST. LOWS TO FALL MOSTLY INTO THE LOWER 30S. AN ASSOCIATED
COLD FRONT WILL ALSO MOVE INTO WRN NEBR TONIGHT AS A CLOSED UPPER
LOW SWINGS FROM NORTH DAKOTA INTO NRN MINNESOTA. THIS WILL DROP
H85 TEMPS TO BELOW 0C ACROSS NCTRL NEBR OVERNIGHT. ACROSS THE
WEST COAST...A STRONG UPPER RIDGE WILL MOVE IN.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 AM CDT TUE MAR 24 2015
COLD FRONT WILL BE PUSHING SOUTH ACROSS THE STATE WED MORNING.
MOSTLY CLOUDY SKIES EARLY WILL GIVE WAY TO DECREASING CLOUDS FOR
THE AFTERNOON. MARGINAL ELEVATED LIFT EARLY...HOWEVER DRY
LOWER/MID LEVELS AND FAST MOVING CLIPPER SHOULD KEEP PRECIP FROM
REACHING THE GROUND AND FORECAST CONTINUES TO BE DRY. COLD
ADVECTION FOR THE DAY WITH AND A SLOW START TO WARM UP DUE TO
MORNING CLOUDS SHOULD RESULT IN A COOL DAY...COMPARED TO RECENT.
HIGHS IN THE UPPER 40S TO MID 50S...WHICH IS FAIRLY CLOSE TO
NORMAL.
THURSDAY NORTHWEST FLOW WILL BRING A CLIPPER THROUGH THE AREA.
AGAIN CONCERNS WITH LOW/MID LEVEL MOISTURE...HOWEVER MODELS
BRINGING SOME PACIFIC MOISTURE ROUNDING THE WESTERN RIDGE WHICH
COULD SATURATE TOP DOWN. ANOTHER CONCERN WILL BE TEMPS. MORNING
TEMPS BELOW FREEZING WHICH COULD RESULT IN PRECIP STARTING OUT AS
SNOW OR A RAIN/SNOW MIX AS CLOUDS INCREASE TEMPS INTO THE 30S. BY
THE AFTERNOON...EVEN WITH THE CLOUDS...MODEL INCREASING TEMPS
INTO THE 40S AND LOWER 50S. MAYBE OPTIMIST WITH TEMPS...HOWEVER
00Z GUIDANCE HAS ACTUALLY CAME IN WARMER. WONDERING IF THE LACK
OF MOISTURE IS BECOMING MORE OF AN ISSUE RESULTING IN MORE PEAKS
OF SUN AND THE ABILITY TO WARM MORE.
ANY LINGERING PRECIP WILL BE CONFINED TO THE HIGHER TERRAIN INTO
THURSDAY NIGHT. CLOUDS HELP KEEP TEMPS WARMER IN THE WEST. HIGH
PRESSURE BUILDS ACROSS THE UPPER MISS RVR VALLEY...NOSES INTO NE
NEB WITH SOME CLEARING AND TEMPS COOL INTO THE LOWER 20S FOR N
CENTRAL.
WARM FRONT TO LIFT ACROSS THE AREA FRIDAY. MODELS IN AGREEMENT
WITH A FASTER TREND OF THE WARM FRONT. THE GFS PRODUCES SOME WARM
ADVECT SHOWERS IN THE MORNING ACROSS PORTIONS OF N CENTRAL...BUT
ONCE AGAIN MOISTURE DEPRIVED LOWER LEVELS AND HAVE GONE DRY.
MAYBE A FEW SPRINKLES BUT DO NOT THINK IT IS WORTH MENTIONED NOW.
RIDGE EXPANDS FOR THE WEEKEND. TEMPS CLIMB WELL ABOVE NORMAL WITH
MOST AREAS AT OR ABOVE 70 FOR SAT. FAST MOVING PACIFIC COLD FRONT
OVERNIGHT SAT. ALTHOUGH A COLD FRONT...CLOUDS WILL LIKELY KEEP
TEMPS UP OVERNIGHT...NEAR 40. WILL MONITOR FOR POSSIBLE LIGHT
PRECIP...HOWEVER BEST LIFT TO THE NORTH WITH THE LATEST RUN.
CLEARING BEHIND THE FRONT WITH BREEZY CONDITIONS IN THE WAKE OF
THE FRONT ON SUNDAY AND WINDS HELP MIX THE BL AND TEMPS REBOUND
NICELY. CONTINUED MILD TO START NEXT WEEK AND DRY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 121 PM CDT TUE MAR 24 2015
BREEZY NORTHWEST WINDS WILL SUBSIDE THIS EVENING THEN TURN TO THE
SOUTHWEST. A WEAK UPPER LEVEL SYSTEM WILL MOVE INTO THE CENTRAL
PLAINS THIS EVENING WHICH WILL BRING POTENTIAL FOR SOME RAIN AND
POSSIBLY A RAIN/SNOW MIX FOR A FEW HOURS ACROSS PORTIONS OF
NORTHERN NEBRASKA...GENERALLY NEAR AND WEST OF KVTN. THIS
PRECIPITATION SHOULD BE QUITE LIGHT...WITH MINIMAL IF ANY
VISIBILITY RESTRICTIONS ESPECIALLY OUTSIDE OF THE HIGHER TERRAIN
NEAR THE PINE RIDGE /KIEN AND KCDR/. SHOULD GET SOME LOWER
CEILINGS OVERNIGHT...BUT VERY DRY AIR IN THE LOW LEVELS WOULD
SUGGEST CEILINGS WILL STAY VFR. WINDS WILL SWITCH BACK TO THE
NORTH WEDNESDAY MORNING AND INCREASE WITH GUSTS UP AROUND 25KTS.
&&
.FIRE WEATHER...
ISSUED AT 335 AM CDT TUE MAR 24 2015
CRITICAL FIRE CONDITIONS ARE FORECAST ACROSS FIRE ZONES 210 AND
219 TODAY...WITH NEAR CRITICAL IN SOUTHERN PORTIONS OF 204 AND
206. STRONG NORTHWEST WINDS TO INCREASE TO 25 TO 35 MPH THIS
AFTERNOON ACROSS ZONES 210 AND 219 AS DEWPOINTS IN THESE AREAS
FALL TO 15 TO 20 AND HIGHS REACH THE MID 60S. THIS WILL BRING MIN
RH VALUES OF 12 TO 17 PERCENT. CONTINUATION OF RED FLAG WARNING
FOR ZONES 210 AND 219 IS WARRANTED WITH CLOSE MONITORING IN ZONES
204 AND 206.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ210-219.
&&
$$
UPDATE...BROOKS
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...MASEK
AVIATION...BROOKS
FIRE WEATHER...ROBERG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1016 AM CDT TUE MAR 24 2015
.SYNOPSIS...
ISSUED AT 335 AM CDT TUE MAR 24 2015
AT 08Z...TWO MAIN AREAS OF SURFACE LOW PRESSURE EXIST. ONE
LOCATED IN FAR ERN WY WHILE THE OTHER IN THE OKLA PNHDL. VERY
LITTLE CURRENTLY ON THE KLBF RADAR EXCEPT FOR A NARROW BAND OF
SHOWERS AND SPRINKLES FROM SWRN CUSTER COUNTY INTO SERN LINCOLN
AND FRONTIER COUNTY. SCATTERED SHOWERS AND THUNDERSTORMS
CURRENTLY EXTEND FROM PARTS OF NCTRL KS INTO SCTRL AND SERN NEBR
AND NWRN MISSOURI WITH JUST OVER 200 LIGHTNING STRIKES THE PAST
HOUR.
&&
.UPDATE...
ISSUED AT 1016 AM CDT TUE MAR 24 2015
FORECAST WAS UPDATED DUE TO RADAR AND CLOUD TRENDS FOR THIS
MORNING AS RAIN SHOWERS OVER NORTH CENTRAL NEBRASKA ARE
PROGRESSING EAST AND SHOULD BE MOSTLY OUT OF THE FORECAST AREA
BY EARLY AFTERNOON. WITH LOW PRESSURE CENTERED OVER SOUTHWEST
NORTH DAKOTA AT MID MORNING...A SURFACE TROUGH WAS LOCATED THROUGH
WESTERN SOUTH DAKOTA AND DOWN THROUGH THE EASTERN NEBRASKA
PANHANDLE. THIS TROUGH WILL MAKE ITS WAY EAST TODAY AND AS CLOUDS
CLEAR BEHIND THE ONGOING PRECIPITATION...WARMING AHEAD OF THE
TROUGH WILL ALLOW SOME VERY WEAK INSTABILITY TO BUILD ROUGHLY FROM
NORTH CENTRAL INTO CENTRAL NEBRASKA THIS AFTERNOON. IT WILL BE
WEAK WITH THE RAP SHOWING 100-200J/KG OF MUCAPE. THIS MAY BE
ENOUGH FOR SOME LIGHT RAIN SHOWERS TO DEVELOP ALONG THE TROUGH
THIS AFTERNOON SO DID ADD IN A SLIGHT CHANCE FOR RAIN SHOWERS IN
THOSE AREAS. NO MENTION OF THUNDER AT THE TIME AS THE INSTABILITY
LOOKS TOO WEAK BUT WILL KEEP AN EYE ON THINGS INTO THE AFTERNOON.
RED FLAG WARNING FOR SOUTHWEST NEBRASKA REMAINS TO LOOK ON TRACK
AS DRY AIR IS EXPECTED TO PUSH INTO THE AREA WITH WINDS INCREASING
AS THE BOUNDARY LAYER BECOMES FULLY MIXED TO AROUND 700MB THIS
AFTERNOON.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT TUE MAR 24 2015
TODAY...THE UPPER TROUGH CURRENTLY ACROSS WRN SD AND THE WRN
PNHDL WILL PROGRESS EASTWARD TODAY. SHOWERS WILL DEVELOP TO THE
EAT OF THIS TROUGH...MAINLY EAST OF A BASSETT THROUGH BROKEN BOW
LINE BY 15Z. LIKELY POPS ACROSS PORTIONS OF
BOYD...HOLT...GARFIELD AND WHEELER COUNTY. THIS IN GOOD AGREEMENT
BY LATEST RAP13...HRRR AND 06Z NAM MODELS. A FEW SHOWERS MAY ALSO
DEVELOP ACROSS FAR NRN NEBR THIS AFTERNOON WITHIN AREA OF A VORT
MAX MOVING THROUGH THAT AREA. HIGHS TODAY REMAIN NEAR PREVIOUS
FORECAST REACHING THE LOW TO MID 60S MOST AREAS. EXCEPTION WILL
BE IN FAR EASTERN AREAS WHERE CONSIDERABLE CLOUDINESS AND SHOWERS
TO HOLD DOWN HIGHS TO THE MID 50S. A FAIRLY STRONG PV ANOMALY
EMERGING FROM NERN CO INTO SWRN NEBR AND NWRN KS THIS MORNING
LOOKS FAVORABLE FOR MIXING DOWN STRONGER WINDS TO THE SURFACE
ACROSS THE SERN PNHDL AND SWRN NEBR INTO THIS AFTERNOON.
NORTHWEST WINDS IN THESE AREAS ARE FORECAST TO INCREASE TO 25 TO
35 MPH THIS AFTERNOON. EXPOSED WHEAT FIELDS AND OTHER TILLED
GROUND WILL BE SUSCEPTIBLE TO BLOWING DUST...AND ADDED AREAS OF
BLOWING DUST THIS AFTERNOON. IN ADDITION...CRITICAL FIRE WEATHER
CONDITIONS MET IN PORTIONS OF SWRN NEBR WITH DETAILS HIGHLIGHTED
IN THE FIRE WEATHER DISCUSSION.
TONIGHT...INCREASING CLOUDINESS ACROSS WRN NEBR AS A DISTURBANCE
IN NERN WY WILL DROP SOUTHEAST INTO NRN NEBR AND FAR SRN SD WITH
A SLIGHT CHANCE FOR SHOWERS...WHICH IS SIMILAR TO PREVIOUS
FORECAST. LOWS TO FALL MOSTLY INTO THE LOWER 30S. AN ASSOCIATED
COLD FRONT WILL ALSO MOVE INTO WRN NEBR TONIGHT AS A CLOSED UPPER
LOW SWINGS FROM NORTH DAKOTA INTO NRN MINNESOTA. THIS WILL DROP
H85 TEMPS TO BELOW 0C ACROSS NCTRL NEBR OVERNIGHT. ACROSS THE
WEST COAST...A STRONG UPPER RIDGE WILL MOVE IN.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 AM CDT TUE MAR 24 2015
COLD FRONT WILL BE PUSHING SOUTH ACROSS THE STATE WED MORNING.
MOSTLY CLOUDY SKIES EARLY WILL GIVE WAY TO DECREASING CLOUDS FOR
THE AFTERNOON. MARGINAL ELEVATED LIFT EARLY...HOWEVER DRY
LOWER/MID LEVELS AND FAST MOVING CLIPPER SHOULD KEEP PRECIP FROM
REACHING THE GROUND AND FORECAST CONTINUES TO BE DRY. COLD
ADVECTION FOR THE DAY WITH AND A SLOW START TO WARM UP DUE TO
MORNING CLOUDS SHOULD RESULT IN A COOL DAY...COMPARED TO RECENT.
HIGHS IN THE UPPER 40S TO MID 50S...WHICH IS FAIRLY CLOSE TO
NORMAL.
THURSDAY NORTHWEST FLOW WILL BRING A CLIPPER THROUGH THE AREA.
AGAIN CONCERNS WITH LOW/MID LEVEL MOISTURE...HOWEVER MODELS
BRINGING SOME PACIFIC MOISTURE ROUNDING THE WESTERN RIDGE WHICH
COULD SATURATE TOP DOWN. ANOTHER CONCERN WILL BE TEMPS. MORNING
TEMPS BELOW FREEZING WHICH COULD RESULT IN PRECIP STARTING OUT AS
SNOW OR A RAIN/SNOW MIX AS CLOUDS INCREASE TEMPS INTO THE 30S. BY
THE AFTERNOON...EVEN WITH THE CLOUDS...MODEL INCREASING TEMPS
INTO THE 40S AND LOWER 50S. MAYBE OPTIMIST WITH TEMPS...HOWEVER
00Z GUIDANCE HAS ACTUALLY CAME IN WARMER. WONDERING IF THE LACK
OF MOISTURE IS BECOMING MORE OF AN ISSUE RESULTING IN MORE PEAKS
OF SUN AND THE ABILITY TO WARM MORE.
ANY LINGERING PRECIP WILL BE CONFINED TO THE HIGHER TERRAIN INTO
THURSDAY NIGHT. CLOUDS HELP KEEP TEMPS WARMER IN THE WEST. HIGH
PRESSURE BUILDS ACROSS THE UPPER MISS RVR VALLEY...NOSES INTO NE
NEB WITH SOME CLEARING AND TEMPS COOL INTO THE LOWER 20S FOR N
CENTRAL.
WARM FRONT TO LIFT ACROSS THE AREA FRIDAY. MODELS IN AGREEMENT
WITH A FASTER TREND OF THE WARM FRONT. THE GFS PRODUCES SOME WARM
ADVECT SHOWERS IN THE MORNING ACROSS PORTIONS OF N CENTRAL...BUT
ONCE AGAIN MOISTURE DEPRIVED LOWER LEVELS AND HAVE GONE DRY.
MAYBE A FEW SPRINKLES BUT DO NOT THINK IT IS WORTH MENTIONED NOW.
RIDGE EXPANDS FOR THE WEEKEND. TEMPS CLIMB WELL ABOVE NORMAL WITH
MOST AREAS AT OR ABOVE 70 FOR SAT. FAST MOVING PACIFIC COLD FRONT
OVERNIGHT SAT. ALTHOUGH A COLD FRONT...CLOUDS WILL LIKELY KEEP
TEMPS UP OVERNIGHT...NEAR 40. WILL MONITOR FOR POSSIBLE LIGHT
PRECIP...HOWEVER BEST LIFT TO THE NORTH WITH THE LATEST RUN.
CLEARING BEHIND THE FRONT WITH BREEZY CONDITIONS IN THE WAKE OF
THE FRONT ON SUNDAY AND WINDS HELP MIX THE BL AND TEMPS REBOUND
NICELY. CONTINUED MILD TO START NEXT WEEK AND DRY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 636 AM CDT TUE MAR 24 2015
VFR CONDITIONS THE NEXT 24 HRS AT THE KLBF AND KVTN TERMINALS. AN
UPPER TROUGH WILL EXIT THE REGION TODAY. NORTHWEST WINDS WILL
INCREASE BEHIND A COLD FRONT. THE STRONGER WINDS WILL OCCUR BY
THIS AFTERNOON AT KLBF WITH WINDS 30016G25KT. WINDS WILL DECOUPLE
BY EARLY THIS EVENING AS SKIES BECOME BROKEN IN MID AND HIGH
CLOUDINESS OVERNIGHT.
&&
.FIRE WEATHER...
ISSUED AT 335 AM CDT TUE MAR 24 2015
CRITICAL FIRE CONDITIONS ARE FORECAST ACROSS FIRE ZONES 210 AND
219 TODAY...WITH NEAR CRITICAL IN SOUTHERN PORTIONS OF 204 AND
206. STRONG NORTHWEST WINDS TO INCREASE TO 25 TO 35 MPH THIS
AFTERNOON ACROSS ZONES 210 AND 219 AS DEWPOINTS IN THESE AREAS
FALL TO 15 TO 20 AND HIGHS REACH THE MID 60S. THIS WILL BRING MIN
RH VALUES OF 12 TO 17 PERCENT. CONTINUATION OF RED FLAG WARNING
FOR ZONES 210 AND 219 IS WARRANTED WITH CLOSE MONITORING IN ZONES
204 AND 206.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM CDT THIS EVENING FOR NEZ210-219.
&&
$$
UPDATE...BROOKS
SYNOPSIS...ROBERG
SHORT TERM...ROBERG
LONG TERM...MASEK
AVIATION...ROBERG
FIRE WEATHER...ROBERG
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1027 PM EDT WED MAR 25 2015
.SYNOPSIS...
A WAVE OF LOW PRESSURE WILL BRING A ROUND OF PRECIPITATION
THURSDAY WHICH WILL START AS RAIN BUT MIX WITH WET SNOW AS COOLER
AIR BUILDS IN BEHIND THE SYSTEM. WINTER-LIKE WEATHER WILL RETURN FRIDAY
WITH BELOW NORMAL TEMPERATURES AND SOME SNOW SHOWERS.
&&
.NEAR TERM /THROUGH THURSDAY/...
HYDROLOGY SECTION UPDATED.
AT 1000 PM...RADAR SHOWED MAINLY DRY CONDITIONS ACROSS THE
REGION...WITH A MIX OF CLOUDS AND CLEAR SKIES. THE MAINLY DRY
WEATHER SHOULD CONTINUE OVERNIGHT WITH THE MAIN FORECAST
CHALLENGE HOW MUCH CLOUD COVER THERE WILL BE. DESPITE THE DRIER
AIR ALOFT...THE 00Z BUF SOUNDING SHOWS MOISTURE BENEATH 2K FT
WHICH IS PROBABLY BEING ENHANCED BY THE MOIST AIR MOVING ACROSS
THE ICE ON LAKE ERIE. THIS MAY RESULT IN A LOW STRATUS DECK IN
SPOTS AS DEPICTED BY THE HRRR AND NAM BUFKIT. OTHERWISE...EXPECT
SOME LINGERING MID AND HIGH CLOUDS WITH THE DEPARTING SYSTEM. IF
SKIES CLEAR LONG ENOUGH...SOME PATCHY FOG IS POSSIBLE.
OTHERWISE...TEMPERATURES SHOULD VERY SLOWLY DROP INTO THE MID TO
UPPER 30S LATE TONIGHT.
18-21Z NAM/GFS/SREF GUIDANCE HAS CONTINUED THE COOLING
TREND...WHICH INCREASES THE LIKELIHOOD THAT PRECIPITATION WILL MIX
WITH SNOW ON THURSDAY. PRECIPITATION WILL PROBABLY START AS
RAIN WITH A CONSENSUS QPF OF ABOUT A HALF INCH. TEMPERATURES WILL
COOL AS A COLD FRONT GRADUALLY SLIDES EAST OF THE REGION DURING
THE DAY WHEN LOW PRESSURE TRACKS ALONG THE FRONT AND PASSES SOUTH
OF THE REGION DURING THE DAY. SNOW WILL MIX IN FIRST IN NORTHERN
AND WESTERN PORTIONS OF THE CWA...INCLUDING THE NIAGARA
FRONTIER...EASTERN LAKE ONTARIO REGION...AND FAR WESTERN PORTIONS
OF THE SOUTHERN TIER. ACCUMULATION SHOULD BE LIGHT DUE TO THE
NEAR OR SLIGHTLY ABOVE FREEZING TEMPERATURES...BUT A WET INCH OR
TWO IS POSSIBLE IN STEADIER SNOWS MAINLY ON GRASSY SURFACES OR
ACROSS HIGHER TERRAIN.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SUNDAY NIGHT/...
WHILE THE CONCERN DURING THE DAYS LEADING UP TO THIS PERIOD HAS BEEN
FOR ENOUGH RAIN TO CAUSE SOME FLOODING...THERE IS NOW A SUGGESTION
BY THE VARIOUS GUIDANCE PACKAGES THAT ENOUGH COLD AIR COULD MAKE IT
FAR ENOUGH SOUTH OF LAKE ONTARIO TO SUPPORT SOME ACCUMULATING SNOW.
THE STEADIEST AND HEAVIEST PCPN WILL HAVE MOVED OFF TO OUR EAST BY
THE START OF THIS PERIOD...BUT WE WILL STILL BE UNDER THE INFLUENCE
OF A VERY WET STORM SYSTEM. AN ELONGATED SFC LOW WILL MAKE ITS WAY
ACROSS NEW ENGLAND THURSDAY NIGHT...TAKING WITH IT THE DEEP LIFT
THAT WAS SUPPLIED BY A PAIR OF 150KT H25 JETLETS AND STRONG H925-70
FRONTOGENETIC FORCING FOUND WITHIN 100 MILES OR SO NORTH OF THE SFC
LOW TRACK. REMOVING THIS LIFT WHILE INTRODUCING MID LEVEL DRYING AND
SOME LOW LEVEL RIDGING WILL LEAD TO MIXED RAIN AND SNOW TAPERING OFF
TO SNOW SHOWERS DURING THE FIRST HALF OF THE NIGHT...WITH ONLY
NUISANCE SNOW SHOWERS EXPECTED DURING THE OVERNIGHT. ADDITIONAL QPF
WILL RANGE FROM LESS THAN A TENTH OF AN INCH OVER THE WESTERN
COUNTIES TO A COUPLE TENTHS OVER THE EASTERN LAKE ONTARIO REGION.
TOTAL RAINFALL FROM THE 12 HOUR EVENT WILL RANGE FROM A HALF TO
THREE QUARTERS OF AN INCH.
AS HAS BEEN ADVERTISED FOR SEVERAL DAYS...THIS AMOUNT OF RAINFALL
ALONG WITH CONTINUED SNOWMELT COULD LEAD TO PROBLEMS ON SOME
TRIBUTARIES...ESPECIALLY THE THREE MAIN WATERWAYS IN THE BUFFALO
AREA (CAZENOVIA, CAYUGA, BUFFALO CREEKS). FOR MORE INFORMATION ON
POTENTIAL HYDROLOGIC CONCERNS SEE THE HYDROLOGY SECTION BELOW.
ON FRIDAY...A SECONDARY COLD FRONTAL TROUGH WILL PUSH SOUTH ACROSS
THE LOWER GREAT LAKES. THIS WILL SUPPORT SCATTERED SNOW SHOWERS WITH
A BETTER CHANCE FOR STEADIER SNOWS ACROSS THE HIGHER TERRAIN IN THE
FAVORABLE COLD AIR ADVECTION/UPSLOPE REGIME. ACCUMULATIONS SHOULD BE
UNDER AN INCH...BUT HIGHER AMOUNTS WILL NOT BE OUT OF THE QUESTION
WEST OF THE FINGER LAKES. TEMPERATURES FRIDAY SHOULD BE A SOLID 10
DEG LOWER THAN THOSE FROM THE PREVIOUS DAY...AS MAX TEMPS ARE ONLY
EXPECTED TO TOP OUT WITHIN A COUPLE DEGREES OF FREEZING.
THE UPSLOPE...CYCLONIC FLOW WILL DELAY ANY REAL CLEARING FRIDAY
NIGHT AS THE MAIN UPPER LEVEL TROUGH WILL SWING ACROSS THE LOWER
GREAT LAKES. THERE SHOULD STILL BE SOME SCATTERED SNOW SHOWERS OVER
THE WESTERN COUNTIES...MAINLY WEST OF THE FINGER LAKES WHERE THE LOW
LEVEL FLOW WILL BE MORE CONDUCIVE FOR A LITTLE LAKE ENHANCEMENT OFF
ONTARIO. EVEN SO...ACCUMULATIONS WILL LIKELY BE MEASURED IN TENTHS
RATHER THAN INCHES. MEANWHILE...CONTINUED COLD ADVECTION SHOULD SEND
OVERNIGHT TEMPERATURES INTO THE TEENS AND PERHAPS EVEN THE SINGLE
DIGITS ACROSS PORTIONS OF THE SOUTHERN TIER AND EAST OF LAKE ONTARIO.
A SPRAWLING ARCTIC HIGH WILL DRIFT FROM THE UPPER GREAT LAKES TO THE
OHIO VALLEY ON SATURDAY. THIS WILL GUARANTEE AN ANOMALOUSLY COLD DAY
ACROSS OUR FORECAST AREA...AS TEMPERATURES ARE ONLY PROJECTED TO
REACH INTO THE MID AND UPPER 20S. THESE VALUES WILL BE SOME 20 DEG
BELOW NORMAL LATE MARCH VALUES. WHILE THE COLD AIR MAY BE
ACCOMPANIED BY SOME RESIDUAL LIGHT SNOW SHOWERS IN THE MORNING...
SKIES SHOULD CLEAR DURING THE COURSE OF THE DAY. THE INCREASED SUN
SHOULD HELP TO TEMPER AN OTHERWISE LATE JANUARY THERMOMETER.
ON SUNDAY...HIGH PRESSURE NOSING NORTH FROM THE MID ATLANTIC STATES
WILL KEEP OUR FORECAST AREA PCPN FREE. THE INCREASED SOUTHERLY FLOW
ON THE BACKSIDE OF THE SFC HIGH WILL PROMOTE NOTABLY MILDER
CONDITIONS AS WELL...WITH TEMPERATURES EXPECTED TO REACH THE LOWER
40S FOR MANY AREAS. A SHORTWAVE DROPPING SOUTHEAST ACROSS THE LOWER
GREAT LAKES SUNDAY NIGHT WILL THEN INTRODUCE THE NEXT ROUND OF SNOW
SHOWERS TO THE REGION.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
A PROGRESSIVE...LOW AMPLITUDE PATTERN WILL BE IN PLACE ACROSS THE
COUNTRY DURING THIS PERIOD...WITH A PARADE OF PACIFIC BASED
SHORTWAVES CROSSING THE GREAT LAKES REGION. WHILE TEMPERATURES WILL
BE COMFORTABLY HIGHER THAN THOSE EXPERIENCED THE PAST COUPLE
WEEKS...THE MERCURY WILL STILL AVERAGE A FEW DEGREES BELOW LATE
MARCH NORMALS.
DEEP LOW PRESSURE WILL PASS BY TO OUR NORTH TO OPEN THIS PERIOD.
WHILE THE MAIN COLD FRONT ASSOCIATED WITH THIS FEATURE IS FORECAST
TO MOVE THROUGH OUR REGION SUNDAY NIGHT...A SECONDARY COLD FRONT
WILL MOVE THROUGH DURING THE DAY MONDAY. THE MINIMAL SYNOPTIC
FORCING FROM THIS FEATURE WILL COMBINE IN THE UNSTABLE CHILLY
AIRMASS TO PRODUCE SOME RAIN AND WET SNOW SHOWERS...ALTHOUGH THE
BULK OF THE DAY WILL LIKELY BE PCPN FREE. IT IS NOT EXPECTED TO BE
COLD ENOUGH TO GET ANY LAKE ENHANCEMENT IN THIS EVENT.
ON TUESDAY...A ROBUST SHORTWAVE IS FORECAST TO TRACK FROM THE MID
WEST AND LOWER OHIO VALLEY TO THE MID ATLANTIC REGION. WHILE THE
BASE OF THE SUPPORTING LONGWAVE TROUGH CROSS OUR REGION...THE
RESULTING SYNOPTIC FORCING IS NOT EXPECTED TO BE STRONG ENOUGH TO
WARRANT ANYTHING MORE THAN SLGT CHC POPS FOR RAIN SHOWERS.
A BURGEONING RIDGE WILL THEN CROSS THE LOWER GREAT LAKES TUESDAY
NIGHT AND WEDNESDAY. WHILE THIS WILL LEAD TO MORE WARMING...THERE
WILL ALSO BE THE CHANCE FOR SOME SHOWERS AHEAD OF THE NEXT COLD
FRONTAL BOUNDARY.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
DRIER AIR HAS MOVED INTO THE REGION...WITH A MIX OF VFR/MVFR
CONDITIONS AT 02Z. THERE IS A LOT OF MOISTURE IN THE LOWEST 2KFT
DUE TO MOIST AIR MOVING ACROSS THE COLD OR FROZEN LAKES. THIS MAY
RESULT IN IFR CIGS AND FOG NORTHEAST OF THE LAKES BUT THIS WILL BE
DIFFICULT TO TIME. EXPECT SLIGHTLY DRIER AIR AND DIMINISHING WINDS
LIKELY TO RESULT IN IMPROVING CONDITIONS LATE TONIGHT.
THIS IMPROVEMENT SHOULD BE SHORT LIVED AS ANOTHER WAVE OF LOW
PRESSURE TRACKS TO THE SOUTH AND BRINGS ABOUT 6 HOURS OF STEADY
PRECIPITATION DURING THE DAY THURSDAY. TEMPERATURES ALOFT WILL
LIKELY BE COLD ENOUGH FOR RAIN TO MIX WITH SNOW. THIS SHOULD LOWER
CIGS TO IFR OR LOWER...BUT THE WET SNOW AND RAIN MIX WILL PROBABLY NOT
LOWER VSBY AS MUCH AS AN EVENT WITH COLDER TEMPERATURES. CONDITIONS
WILL IMPROVE FROM SW-NE LATE IN THE DAY AS THE SYSTEM EXITS.
OUTLOOK...
THURSDAY NIGHT THROUGH FRIDAY NIGHT...MVFR WITH A CHANCE OF SNOW
SHOWERS.
SATURDAY AND SUNDAY...VFR.
MONDAY...MVFR IN RAIN/SNOW SHOWERS.
&&
.MARINE...
SOUTHERLY FLOW TODAY WILL BECOME GUSTY BUT THE OFFSHORE FLOW SHOULD
KEEP THE HIGHER WAVE ACTION OF 2-4 FEET OUT IN THE OPEN WATERS OF
LAKE ONTARIO. WEST TO NORTHWEST WINDS LATER THIS WEEK WILL INCREASE
BEHIND A COLD FRONT WITH SMALL CRAFT CONDITIONS POSSIBLE ON THE OPEN
WATERS OF LAKE ONTARIO LATER FRIDAY NIGHT.
&&
.HYDROLOGY...
A WARM FRONT BROUGHT ABOUT A TENTH OF AN INCH OF RAIN TO THE
RIVER AND CREEK BASINS. HIGH TEMPERATURES WERE ONLY IN THE LOWER TO MID
40S...AND EVEN A BIT COOLER THAN THAT IN THE SOUTHERN TIER. AS A
RESULT THE CREEK AND RIVER RESPONSE WILL PROBABLY BE A BIT LESS
THAN WHAT WAS EXPECTED.
THERE IS ANOTHER WAVE OF LOW PRESSURE WHICH SHOULD BRING ABOUT
ANOTHER HALF INCH OF QPF. HOWEVER...GUIDANCE HAS CONTINUED TO
TREND COLDER WITH THIS SYSTEM. TEMPERATURES ON THURSDAY MAY ONLY
BE IN THE UPPER 30S WHICH WOULD REDUCE RUN-OFF FROM SNOW MELT. THE
COOLER TEMPERATURE FORECAST HAS ALSO LOWERED THE EXPECTED THAWING
DEGREE HOURS TO ABOUT 250 TO 300.
ALTHOUGH THIS SHIFT IN MODEL GUIDANCE HAS DIMINISHED THE THREAT
FOR FLOODING...THE THREAT IS NOT COMPLETELY GONE. THERE WILL BE
SHARPLY WARMER AIR JUST TO THE SOUTH OF THE REGION...AND ANY
NORTHWARD SHIFT IN THIS WARM AIR COULD DRAMATICALLY INCREASE RUN-
OFF AND FLOWS. THERE IS ALSO QUITE A BIT OF ICE ALONG THE SHORES
OF THE CAZENOVIA AND BUFFALO CREEKS. IF LEVELS RISE TO ACTION
STAGE...THIS COULD CAUSE THIS ICE TO FLOAT AND BECOME JAMMED.
BECAUSE OF THIS...WE WILL CONTINUE TO KEEP A CLOSE EYE ON THE
SITUATION. IT IS STILL POSSIBLE THAT FLOOD WATCHES WILL BE NEEDED
FOR A PORTION OF THE AREA...ESPECIALLY IF THE LOW TAKES EVEN A
SLIGHTLY MORE NORTHWARD TRACK THAN WHAT IS CURRENTLY FORECAST.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL/WCH
NEAR TERM...APFFEL/WCH
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...APFFEL
MARINE...CHURCH/WCH
HYDROLOGY...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
909 PM EDT WED MAR 25 2015
.SYNOPSIS...
A WAVE OF LOW PRESSURE WILL BRING A ROUND OF PRECIPITATION
THURSDAY WHICH WILL START AS RAIN BUT MIX WITH WET SNOW AS COOLER
AIR BUILDS IN BEHIND THE SYSTEM. WINTER-LIKE WEATHER WILL RETURN FRIDAY
WITH BELOW NORMAL TEMPERATURES AND SOME SNOW SHOWERS.
&&
.NEAR TERM /THROUGH THURSDAY/...
HYDROLOGY SECTION UPDATED.
AT 730 PM...STEADY RAIN HAS PRETTY MUCH ENDED AS A WARM FRONT AND
MID-LEVEL DISTURBANCE EXIT TO THE NORTHEAST. THERE ARE SOME LIGHT
RAIN SHOWERS OR DRIZZLE BEHIND THIS...BUT THESE SHOULD TAPER OFF
AS DRIER AIR ALOFT MOVES IN THIS EVENING. THIS DRIER AIR CAN BE
SEEN SATELLITE LOOPS...WITH THE LEADING EDGE OF THIS ENTERING THE
NIAGARA FRONTIER.
AFTER THIS...EXPECT DRY WEATHER OVERNIGHT WITH THE MAIN FORECAST
CHALLENGE HOW MUCH CLOUD COVER THERE WILL BE. DESPITE THE DRIER
AIR ALOFT...THERE WILL BE MOIST AIR BELOW 2K FT WHICH WILL MOVE ACROSS
THE COLD OR FROZEN LAKES. THIS MAY RESULT IN A LOW STRATUS DECK IN
SPOTS AS DEPICTED BY THE HRRR AND NAM BUFKIT. OTHERWISE...EXPECT
SOME LINGERING MID AND HIGH CLOUDS WITH THE DEPARTING SYSTEM.
WINDS SHOULD KEEP THE BOUNDARY LAYER MIXED WITH RELATIVELY WARM
TEMPERATURES IN THE 40S THROUGH THE EVENING HOURS EXPECTED TO DROP
MODESTLY INTO THE MID TO UPPER 30S LATE TONIGHT.
18-21Z NAM/GFS/SREF GUIDANCE HAS CONTINUED THE COOLING
TREND...WHICH INCREASES THE LIKELIHOOD THAT PRECIPITATION WILL MIX
WITH SNOW ON THURSDAY. PRECIPITATION WILL PROBABLY START AS
RAIN WITH A CONSENSUS QPF OF ABOUT A HALF INCH. TEMPERATURES WILL
COOL AS A COLD FRONT GRADUALLY SLIDES EAST OF THE REGION DURING
THE DAY WHEN LOW PRESSURE TRACKS ALONG THE FRONT AND PASSES SOUTH
OF THE REGION DURING THE DAY. SNOW WILL MIX IN FIRST IN NORTHERN
AND WESTERN PORTIONS OF THE CWA...INCLUDING THE NIAGARA
FRONTIER...EASTERN LAKE ONTARIO REGION...AND FAR WESTERN PORTIONS
OF THE SOUTHERN TIER. ACCUMULATION SHOULD BE LIGHT DUE TO THE
NEAR OR SLIGHTLY ABOVE FREEZING TEMPERATURES...BUT A WET INCH OR
TWO IS POSSIBLE IN STEADIER SNOWS MAINLY ON GRASSY SURFACES OR
ACROSS HIGHER TERRAIN.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SUNDAY NIGHT/...
WHILE THE CONCERN DURING THE DAYS LEADING UP TO THIS PERIOD HAS BEEN
FOR ENOUGH RAIN TO CAUSE SOME FLOODING...THERE IS NOW A SUGGESTION
BY THE VARIOUS GUIDANCE PACKAGES THAT ENOUGH COLD AIR COULD MAKE IT
FAR ENOUGH SOUTH OF LAKE ONTARIO TO SUPPORT SOME ACCUMULATING SNOW.
THE STEADIEST AND HEAVIEST PCPN WILL HAVE MOVED OFF TO OUR EAST BY
THE START OF THIS PERIOD...BUT WE WILL STILL BE UNDER THE INFLUENCE
OF A VERY WET STORM SYSTEM. AN ELONGATED SFC LOW WILL MAKE ITS WAY
ACROSS NEW ENGLAND THURSDAY NIGHT...TAKING WITH IT THE DEEP LIFT
THAT WAS SUPPLIED BY A PAIR OF 150KT H25 JETLETS AND STRONG H925-70
FRONTOGENETIC FORCING FOUND WITHIN 100 MILES OR SO NORTH OF THE SFC
LOW TRACK. REMOVING THIS LIFT WHILE INTRODUCING MID LEVEL DRYING AND
SOME LOW LEVEL RIDGING WILL LEAD TO MIXED RAIN AND SNOW TAPERING OFF
TO SNOW SHOWERS DURING THE FIRST HALF OF THE NIGHT...WITH ONLY
NUISANCE SNOW SHOWERS EXPECTED DURING THE OVERNIGHT. ADDITIONAL QPF
WILL RANGE FROM LESS THAN A TENTH OF AN INCH OVER THE WESTERN
COUNTIES TO A COUPLE TENTHS OVER THE EASTERN LAKE ONTARIO REGION.
TOTAL RAINFALL FROM THE 12 HOUR EVENT WILL RANGE FROM A HALF TO
THREE QUARTERS OF AN INCH.
AS HAS BEEN ADVERTISED FOR SEVERAL DAYS...THIS AMOUNT OF RAINFALL
ALONG WITH CONTINUED SNOWMELT COULD LEAD TO PROBLEMS ON SOME
TRIBUTARIES...ESPECIALLY THE THREE MAIN WATERWAYS IN THE BUFFALO
AREA (CAZENOVIA, CAYUGA, BUFFALO CREEKS). FOR MORE INFORMATION ON
POTENTIAL HYDROLOGIC CONCERNS SEE THE HYDROLOGY SECTION BELOW.
ON FRIDAY...A SECONDARY COLD FRONTAL TROUGH WILL PUSH SOUTH ACROSS
THE LOWER GREAT LAKES. THIS WILL SUPPORT SCATTERED SNOW SHOWERS WITH
A BETTER CHANCE FOR STEADIER SNOWS ACROSS THE HIGHER TERRAIN IN THE
FAVORABLE COLD AIR ADVECTION/UPSLOPE REGIME. ACCUMULATIONS SHOULD BE
UNDER AN INCH...BUT HIGHER AMOUNTS WILL NOT BE OUT OF THE QUESTION
WEST OF THE FINGER LAKES. TEMPERATURES FRIDAY SHOULD BE A SOLID 10
DEG LOWER THAN THOSE FROM THE PREVIOUS DAY...AS MAX TEMPS ARE ONLY
EXPECTED TO TOP OUT WITHIN A COUPLE DEGREES OF FREEZING.
THE UPSLOPE...CYCLONIC FLOW WILL DELAY ANY REAL CLEARING FRIDAY
NIGHT AS THE MAIN UPPER LEVEL TROUGH WILL SWING ACROSS THE LOWER
GREAT LAKES. THERE SHOULD STILL BE SOME SCATTERED SNOW SHOWERS OVER
THE WESTERN COUNTIES...MAINLY WEST OF THE FINGER LAKES WHERE THE LOW
LEVEL FLOW WILL BE MORE CONDUCIVE FOR A LITTLE LAKE ENHANCEMENT OFF
ONTARIO. EVEN SO...ACCUMULATIONS WILL LIKELY BE MEASURED IN TENTHS
RATHER THAN INCHES. MEANWHILE...CONTINUED COLD ADVECTION SHOULD SEND
OVERNIGHT TEMPERATURES INTO THE TEENS AND PERHAPS EVEN THE SINGLE
DIGITS ACROSS PORTIONS OF THE SOUTHERN TIER AND EAST OF LAKE ONTARIO.
A SPRAWLING ARCTIC HIGH WILL DRIFT FROM THE UPPER GREAT LAKES TO THE
OHIO VALLEY ON SATURDAY. THIS WILL GUARANTEE AN ANOMALOUSLY COLD DAY
ACROSS OUR FORECAST AREA...AS TEMPERATURES ARE ONLY PROJECTED TO
REACH INTO THE MID AND UPPER 20S. THESE VALUES WILL BE SOME 20 DEG
BELOW NORMAL LATE MARCH VALUES. WHILE THE COLD AIR MAY BE
ACCOMPANIED BY SOME RESIDUAL LIGHT SNOW SHOWERS IN THE MORNING...
SKIES SHOULD CLEAR DURING THE COURSE OF THE DAY. THE INCREASED SUN
SHOULD HELP TO TEMPER AN OTHERWISE LATE JANUARY THERMOMETER.
ON SUNDAY...HIGH PRESSURE NOSING NORTH FROM THE MID ATLANTIC STATES
WILL KEEP OUR FORECAST AREA PCPN FREE. THE INCREASED SOUTHERLY FLOW
ON THE BACKSIDE OF THE SFC HIGH WILL PROMOTE NOTABLY MILDER
CONDITIONS AS WELL...WITH TEMPERATURES EXPECTED TO REACH THE LOWER
40S FOR MANY AREAS. A SHORTWAVE DROPPING SOUTHEAST ACROSS THE LOWER
GREAT LAKES SUNDAY NIGHT WILL THEN INTRODUCE THE NEXT ROUND OF SNOW
SHOWERS TO THE REGION.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
A PROGRESSIVE...LOW AMPLITUDE PATTERN WILL BE IN PLACE ACROSS THE
COUNTRY DURING THIS PERIOD...WITH A PARADE OF PACIFIC BASED
SHORTWAVES CROSSING THE GREAT LAKES REGION. WHILE TEMPERATURES WILL
BE COMFORTABLY HIGHER THAN THOSE EXPERIENCED THE PAST COUPLE
WEEKS...THE MERCURY WILL STILL AVERAGE A FEW DEGREES BELOW LATE
MARCH NORMALS.
DEEP LOW PRESSURE WILL PASS BY TO OUR NORTH TO OPEN THIS PERIOD.
WHILE THE MAIN COLD FRONT ASSOCIATED WITH THIS FEATURE IS FORECAST
TO MOVE THROUGH OUR REGION SUNDAY NIGHT...A SECONDARY COLD FRONT
WILL MOVE THROUGH DURING THE DAY MONDAY. THE MINIMAL SYNOPTIC
FORCING FROM THIS FEATURE WILL COMBINE IN THE UNSTABLE CHILLY
AIRMASS TO PRODUCE SOME RAIN AND WET SNOW SHOWERS...ALTHOUGH THE
BULK OF THE DAY WILL LIKELY BE PCPN FREE. IT IS NOT EXPECTED TO BE
COLD ENOUGH TO GET ANY LAKE ENHANCEMENT IN THIS EVENT.
ON TUESDAY...A ROBUST SHORTWAVE IS FORECAST TO TRACK FROM THE MID
WEST AND LOWER OHIO VALLEY TO THE MID ATLANTIC REGION. WHILE THE
BASE OF THE SUPPORTING LONGWAVE TROUGH CROSS OUR REGION...THE
RESULTING SYNOPTIC FORCING IS NOT EXPECTED TO BE STRONG ENOUGH TO
WARRANT ANYTHING MORE THAN SLGT CHC POPS FOR RAIN SHOWERS.
A BURGEONING RIDGE WILL THEN CROSS THE LOWER GREAT LAKES TUESDAY
NIGHT AND WEDNESDAY. WHILE THIS WILL LEAD TO MORE WARMING...THERE
WILL ALSO BE THE CHANCE FOR SOME SHOWERS AHEAD OF THE NEXT COLD
FRONTAL BOUNDARY.
&&
.AVIATION /01Z THURSDAY THROUGH MONDAY/...
DRIER AIR WILL BUILD INTO THE REGION FROM SW-NE THIS EVENING...HOWEVER
IN THE LOWEST 2K FEET THERE WILL BE MOISTURE FROM DEW POINTS IN
THE LOWER 40S MOVING ACROSS THE ICE OR COLD WATERS OF LAKE ERIE
AND ONTARIO. THIS MAY RESULT IN IFR CIGS (AND FOG) BUT THIS WILL
BE DIFFICULT TO TIME. EXPECT SLIGHTLY DRIER AIR AND DIMINISHING
WINDS LIKELY TO RESULT IN IMPROVING CONDITIONS LATE TONIGHT.
THIS IMPROVEMENT SHOULD BE SHORT LIVED AS ANOTHER WAVE OF LOW
PRESSURE TRACKS TO THE SOUTH AND BRINGS ABOUT 6 HOURS OF STEADY
PRECIPITATION DURING THE DAY THURSDAY. TEMPERATURES ALOFT WILL
LIKELY BE COLD ENOUGH FOR RAIN TO MIX WITH SNOW. THIS SHOULD LOWER
CIGS TO IFR OR LOWER...BUT THE WET SNOW AND RAIN MIX WILL PROBABLY NOT
LOWER VSBY AS MUCH AS AN EVENT WITH COLDER TEMPERATURES. CONDITIONS
WILL IMPROVE FROM SW-NE LATE IN THE DAY AS THE SYSTEM EXITS.
OUTLOOK...
THURSDAY NIGHT THROUGH FRIDAY NIGHT...MVFR WITH A CHANCE OF SNOW
SHOWERS.
SATURDAY AND SUNDAY...VFR.
MONDAY...MVFR IN RAIN/SNOW SHOWERS.
&&
.MARINE...
SOUTHERLY FLOW TODAY WILL BECOME GUSTY BUT THE OFFSHORE FLOW SHOULD
KEEP THE HIGHER WAVE ACTION OF 2-4 FEET OUT IN THE OPEN WATERS OF
LAKE ONTARIO. WEST TO NORTHWEST WINDS LATER THIS WEEK WILL INCREASE
BEHIND A COLD FRONT WITH SMALL CRAFT CONDITIONS POSSIBLE ON THE OPEN
WATERS OF LAKE ONTARIO LATER FRIDAY NIGHT.
&&
.HYDROLOGY...
A WARM FRONT BROUGHT ABOUT A TENTH OF AN INCH OF RAIN TO THE
RIVER AND CREEK BASINS. HIGH TEMPERATURES WERE ONLY IN THE LOWER TO MID
40S...AND EVEN A BIT COOLER THAN THAT IN THE SOUTHERN TIER. AS A
RESULT THE CREEK AND RIVER RESPONSE WILL PROBABLY BE A BIT LESS
THAN WHAT WAS EXPECTED.
THERE IS ANOTHER WAVE OF LOW PRESSURE WHICH SHOULD BRING ABOUT
ANOTHER HALF INCH OF QPF. HOWEVER...GUIDANCE HAS CONTINUED TO
TREND COLDER WITH THIS SYSTEM. TEMPERATURES ON THURSDAY MAY ONLY
BE IN THE UPPER 30S WHICH WOULD REDUCE RUN-OFF FROM SNOW MELT. THE
COOLER TEMPERATURE FORECAST HAS ALSO LOWERED THE EXPECTED THAWING
DEGREE HOURS TO ABOUT 250 TO 300.
ALTHOUGH THIS SHIFT IN MODEL GUIDANCE HAS DIMINISHED THE THREAT
FOR FLOODING...THE THREAT IS NOT COMPLETELY GONE. THERE WILL BE
SHARPLY WARMER AIR JUST TO THE SOUTH OF THE REGION...AND ANY
NORTHWARD SHIFT IN THIS WARM AIR COULD DRAMATICALLY INCREASE RUN-
OFF AND FLOWS. THERE IS ALSO QUITE A BIT OF ICE ALONG THE SHORES
OF THE CAZENOVIA AND BUFFALO CREEKS. IF LEVELS RISE TO ACTION
STAGE...THIS COULD CAUSE THIS ICE TO FLOAT AND BECOME JAMMED.
BECAUSE OF THIS...WE WILL CONTINUE TO KEEP A CLOSE EYE ON THE
SITUATION. IT IS STILL POSSIBLE THAT FLOOD WATCHES WILL BE NEEDED
FOR A PORTION OF THE AREA...ESPECIALLY IF THE LOW TAKES EVEN A
SLIGHTLY MORE NORTHWARD TRACK THAN WHAT IS CURRENTLY FORECAST.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL/WCH
NEAR TERM...APFFEL/WCH
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...APFFEL
MARINE...CHURCH/WCH
HYDROLOGY...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
755 PM EDT WED MAR 25 2015
.SYNOPSIS...
A WAVE OF LOW PRESSURE WILL BRING A ROUND OF PRECIPITATION
THURSDAY WHICH WILL START AS RAIN BUT MIX WITH WET SNOW AS COOLER
AIR BUILDS IN BEHIND THE SYSTEM. WINTER-LIKE WEATHER WILL RETURN FRIDAY
WITH BELOW NORMAL TEMPERATURES AND SOME SNOW SHOWERS.
&&
.NEAR TERM /THROUGH THURSDAY/...
AT 730 PM...STEADY RAIN HAS PRETTY MUCH ENDED AS A WARM FRONT AND
MID-LEVEL DISTURBANCE EXIT TO THE NORTHEAST. THERE ARE SOME LIGHT
RAIN SHOWERS OR DRIZZLE BEHIND THIS...BUT THESE SHOULD TAPER OFF
AS DRIER AIR ALOFT MOVES IN THIS EVENING. THIS DRIER AIR CAN BE
SEEN SATELLITE LOOPS...WITH THE LEADING EDGE OF THIS ENTERING THE
NIAGARA FRONTIER.
AFTER THIS...EXPECT DRY WEATHER OVERNIGHT WITH THE MAIN FORECAST
CHALLENGE HOW MUCH CLOUD COVER THERE WILL BE. DESPITE THE DRIER
AIR ALOFT...THERE WILL BE MOIST AIR BELOW 2K FT WHICH WILL MOVE ACROSS
THE COLD OR FROZEN LAKES. THIS MAY RESULT IN A LOW STRATUS DECK IN
SPOTS AS DEPICTED BY THE HRRR AND NAM BUFKIT. OTHERWISE...EXPECT
SOME LINGERING MID AND HIGH CLOUDS WITH THE DEPARTING SYSTEM.
WINDS SHOULD KEEP THE BOUNDARY LAYER MIXED WITH RELATIVELY WARM
TEMPERATURES IN THE 40S THROUGH THE EVENING HOURS EXPECTED TO DROP
MODESTLY INTO THE MID TO UPPER 30S LATE TONIGHT.
18-21Z NAM/GFS/SREF GUIDANCE HAS CONTINUED THE COOLING
TREND...WHICH INCREASES THE LIKELIHOOD THAT PRECIPITATION WILL MIX
WITH SNOW ON THURSDAY. PRECIPITATION WILL PROBABLY START AS
RAIN WITH A CONSENSUS QPF OF ABOUT A HALF INCH. TEMPERATURES WILL
COOL AS A COLD FRONT GRADUALLY SLIDES EAST OF THE REGION DURING
THE DAY WHEN LOW PRESSURE TRACKS ALONG THE FRONT AND PASSES SOUTH
OF THE REGION DURING THE DAY. SNOW WILL MIX IN FIRST IN NORTHERN
AND WESTERN PORTIONS OF THE CWA...INCLUDING THE NIAGARA
FRONTIER...EASTERN LAKE ONTARIO REGION...AND FAR WESTERN PORTIONS
OF THE SOUTHERN TIER. ACCUMULATION SHOULD BE LIGHT DUE TO THE
NEAR OR SLIGHTLY ABOVE FREEZING TEMPERATURES...BUT A WET INCH OR
TWO IS POSSIBLE IN STEADIER SNOWS MAINLY ON GRASSY SURFACES OR
ACROSS HIGHER TERRAIN.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SUNDAY NIGHT/...
WHILE THE CONCERN DURING THE DAYS LEADING UP TO THIS PERIOD HAS BEEN
FOR ENOUGH RAIN TO CAUSE SOME FLOODING...THERE IS NOW A SUGGESTION
BY THE VARIOUS GUIDANCE PACKAGES THAT ENOUGH COLD AIR COULD MAKE IT
FAR ENOUGH SOUTH OF LAKE ONTARIO TO SUPPORT SOME ACCUMULATING SNOW.
THE STEADIEST AND HEAVIEST PCPN WILL HAVE MOVED OFF TO OUR EAST BY
THE START OF THIS PERIOD...BUT WE WILL STILL BE UNDER THE INFLUENCE
OF A VERY WET STORM SYSTEM. AN ELONGATED SFC LOW WILL MAKE ITS WAY
ACROSS NEW ENGLAND THURSDAY NIGHT...TAKING WITH IT THE DEEP LIFT
THAT WAS SUPPLIED BY A PAIR OF 150KT H25 JETLETS AND STRONG H925-70
FRONTOGENETIC FORCING FOUND WITHIN 100 MILES OR SO NORTH OF THE SFC
LOW TRACK. REMOVING THIS LIFT WHILE INTRODUCING MID LEVEL DRYING AND
SOME LOW LEVEL RIDGING WILL LEAD TO MIXED RAIN AND SNOW TAPERING OFF
TO SNOW SHOWERS DURING THE FIRST HALF OF THE NIGHT...WITH ONLY
NUISANCE SNOW SHOWERS EXPECTED DURING THE OVERNIGHT. ADDITIONAL QPF
WILL RANGE FROM LESS THAN A TENTH OF AN INCH OVER THE WESTERN
COUNTIES TO A COUPLE TENTHS OVER THE EASTERN LAKE ONTARIO REGION.
TOTAL RAINFALL FROM THE 12 HOUR EVENT WILL RANGE FROM A HALF TO
THREE QUARTERS OF AN INCH.
AS HAS BEEN ADVERTISED FOR SEVERAL DAYS...THIS AMOUNT OF RAINFALL
ALONG WITH CONTINUED SNOWMELT COULD LEAD TO PROBLEMS ON SOME
TRIBUTARIES...ESPECIALLY THE THREE MAIN WATERWAYS IN THE BUFFALO
AREA (CAZENOVIA, CAYUGA, BUFFALO CREEKS). FOR MORE INFORMATION ON
POTENTIAL HYDROLOGIC CONCERNS SEE THE HYDROLOGY SECTION BELOW.
ON FRIDAY...A SECONDARY COLD FRONTAL TROUGH WILL PUSH SOUTH ACROSS
THE LOWER GREAT LAKES. THIS WILL SUPPORT SCATTERED SNOW SHOWERS WITH
A BETTER CHANCE FOR STEADIER SNOWS ACROSS THE HIGHER TERRAIN IN THE
FAVORABLE COLD AIR ADVECTION/UPSLOPE REGIME. ACCUMULATIONS SHOULD BE
UNDER AN INCH...BUT HIGHER AMOUNTS WILL NOT BE OUT OF THE QUESTION
WEST OF THE FINGER LAKES. TEMPERATURES FRIDAY SHOULD BE A SOLID 10
DEG LOWER THAN THOSE FROM THE PREVIOUS DAY...AS MAX TEMPS ARE ONLY
EXPECTED TO TOP OUT WITHIN A COUPLE DEGREES OF FREEZING.
THE UPSLOPE...CYCLONIC FLOW WILL DELAY ANY REAL CLEARING FRIDAY
NIGHT AS THE MAIN UPPER LEVEL TROUGH WILL SWING ACROSS THE LOWER
GREAT LAKES. THERE SHOULD STILL BE SOME SCATTERED SNOW SHOWERS OVER
THE WESTERN COUNTIES...MAINLY WEST OF THE FINGER LAKES WHERE THE LOW
LEVEL FLOW WILL BE MORE CONDUCIVE FOR A LITTLE LAKE ENHANCEMENT OFF
ONTARIO. EVEN SO...ACCUMULATIONS WILL LIKELY BE MEASURED IN TENTHS
RATHER THAN INCHES. MEANWHILE...CONTINUED COLD ADVECTION SHOULD SEND
OVERNIGHT TEMPERATURES INTO THE TEENS AND PERHAPS EVEN THE SINGLE
DIGITS ACROSS PORTIONS OF THE SOUTHERN TIER AND EAST OF LAKE ONTARIO.
A SPRAWLING ARCTIC HIGH WILL DRIFT FROM THE UPPER GREAT LAKES TO THE
OHIO VALLEY ON SATURDAY. THIS WILL GUARANTEE AN ANOMALOUSLY COLD DAY
ACROSS OUR FORECAST AREA...AS TEMPERATURES ARE ONLY PROJECTED TO
REACH INTO THE MID AND UPPER 20S. THESE VALUES WILL BE SOME 20 DEG
BELOW NORMAL LATE MARCH VALUES. WHILE THE COLD AIR MAY BE
ACCOMPANIED BY SOME RESIDUAL LIGHT SNOW SHOWERS IN THE MORNING...
SKIES SHOULD CLEAR DURING THE COURSE OF THE DAY. THE INCREASED SUN
SHOULD HELP TO TEMPER AN OTHERWISE LATE JANUARY THERMOMETER.
ON SUNDAY...HIGH PRESSURE NOSING NORTH FROM THE MID ATLANTIC STATES
WILL KEEP OUR FORECAST AREA PCPN FREE. THE INCREASED SOUTHERLY FLOW
ON THE BACKSIDE OF THE SFC HIGH WILL PROMOTE NOTABLY MILDER
CONDITIONS AS WELL...WITH TEMPERATURES EXPECTED TO REACH THE LOWER
40S FOR MANY AREAS. A SHORTWAVE DROPPING SOUTHEAST ACROSS THE LOWER
GREAT LAKES SUNDAY NIGHT WILL THEN INTRODUCE THE NEXT ROUND OF SNOW
SHOWERS TO THE REGION.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
A PROGRESSIVE...LOW AMPLITUDE PATTERN WILL BE IN PLACE ACROSS THE
COUNTRY DURING THIS PERIOD...WITH A PARADE OF PACIFIC BASED
SHORTWAVES CROSSING THE GREAT LAKES REGION. WHILE TEMPERATURES WILL
BE COMFORTABLY HIGHER THAN THOSE EXPERIENCED THE PAST COUPLE
WEEKS...THE MERCURY WILL STILL AVERAGE A FEW DEGREES BELOW LATE
MARCH NORMALS.
DEEP LOW PRESSURE WILL PASS BY TO OUR NORTH TO OPEN THIS PERIOD.
WHILE THE MAIN COLD FRONT ASSOCIATED WITH THIS FEATURE IS FORECAST
TO MOVE THROUGH OUR REGION SUNDAY NIGHT...A SECONDARY COLD FRONT
WILL MOVE THROUGH DURING THE DAY MONDAY. THE MINIMAL SYNOPTIC
FORCING FROM THIS FEATURE WILL COMBINE IN THE UNSTABLE CHILLY
AIRMASS TO PRODUCE SOME RAIN AND WET SNOW SHOWERS...ALTHOUGH THE
BULK OF THE DAY WILL LIKELY BE PCPN FREE. IT IS NOT EXPECTED TO BE
COLD ENOUGH TO GET ANY LAKE ENHANCEMENT IN THIS EVENT.
ON TUESDAY...A ROBUST SHORTWAVE IS FORECAST TO TRACK FROM THE MID
WEST AND LOWER OHIO VALLEY TO THE MID ATLANTIC REGION. WHILE THE
BASE OF THE SUPPORTING LONGWAVE TROUGH CROSS OUR REGION...THE
RESULTING SYNOPTIC FORCING IS NOT EXPECTED TO BE STRONG ENOUGH TO
WARRANT ANYTHING MORE THAN SLGT CHC POPS FOR RAIN SHOWERS.
A BURGEONING RIDGE WILL THEN CROSS THE LOWER GREAT LAKES TUESDAY
NIGHT AND WEDNESDAY. WHILE THIS WILL LEAD TO MORE WARMING...THERE
WILL ALSO BE THE CHANCE FOR SOME SHOWERS AHEAD OF THE NEXT COLD
FRONTAL BOUNDARY.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
DRIER AIR WILL BUILD INTO THE REGION FROM SW-NE THIS EVENING...HOWEVER
IN THE LOWEST 2K FEET THERE WILL BE MOISTURE FROM DEW POINTS IN
THE LOWER 40S MOVING ACROSS THE ICE OR COLD WATERS OF LAKE ERIE
AND ONTARIO. THIS MAY RESULT IN IFR CIGS (AND FOG) BUT THIS WILL
BE DIFFICULT TO TIME. EXPECT SLIGHTLY DRIER AIR AND DIMINISHING
WINDS LIKELY TO RESULT IN IMPROVING CONDITIONS LATE TONIGHT.
THIS IMPROVEMENT SHOULD BE SHORT LIVED AS ANOTHER WAVE OF LOW
PRESSURE TRACKS TO THE SOUTH AND BRINGS ABOUT 6 HOURS OF STEADY
PRECIPITATION DURING THE DAY THURSDAY. TEMPERATURES ALOFT WILL
LIKELY BE COLD ENOUGH FOR RAIN TO MIX WITH SNOW. THIS SHOULD LOWER
CIGS TO IFR OR LOWER...BUT THE WET SNOW AND RAIN MIX WILL PROBABLY NOT
LOWER VSBY AS MUCH AS AN EVENT WITH COLDER TEMPERATURES. CONDITIONS
WILL IMPROVE FROM SW-NE LATE IN THE DAY AS THE SYSTEM EXITS.
OUTLOOK...
THURSDAY NIGHT THROUGH FRIDAY NIGHT...MVFR WITH A CHANCE OF SNOW
SHOWERS.
SATURDAY AND SUNDAY...VFR.
MONDAY...MVFR IN RAIN/SNOW SHOWERS.
&&
.MARINE...
SOUTHERLY FLOW TODAY WILL BECOME GUSTY BUT THE OFFSHORE FLOW SHOULD
KEEP THE HIGHER WAVE ACTION OF 2-4 FEET OUT IN THE OPEN WATERS OF
LAKE ONTARIO. WEST TO NORTHWEST WINDS LATER THIS WEEK WILL INCREASE
BEHIND A COLD FRONT WITH SMALL CRAFT CONDITIONS POSSIBLE ON THE OPEN
WATERS OF LAKE ONTARIO LATER FRIDAY NIGHT.
&&
.HYDROLOGY...
A WARM FRONT WILL PRODUCE LIGHT RAIN TODAY WITH A TENTH TO A
QUARTER INCH EXPECTED. ALTHOUGH WARM TEMPERATURES WILL ACCOMPANY
THIS RAINFALL...IT SHOULD NOT BE ENOUGH TO CAUSE ANY FLOODING
CONCERNS. A SECOND WAVE OF LOW PRESSURE WILL MOVE ALONG A
SHARPENING BAROCLINIC ZONE LATE TONIGHT AND THURSDAY WITH THE
POTENTIAL FOR GREATER PRECIPITATION AMOUNTS. MODEL GUIDANCE
VARIES ON THE EXACT TRACK OF THIS SYSTEM...WITH RAIN AMOUNTS
ANYWHERE FROM A THIRD TO A HALF OF AN INCH DEPENDING ON
THE EXACT TRACK. MODEL CONSENSUS HAS SHIFTED SOUTHWARD AND COLDER
WITH THE TRACK OF THE LOW...WHICH MAY RESULT IN COOLER (JUST ABOVE
FREEZING) TEMPERATURES DURING THE DAY THURSDAY THUS SOME OF THE
PRECIP IS EXPECTED TO FALL AS SNOW. HOWEVER...IT WOULD ONLY TAKE A
SLIGHT NORTHWARD SHIFT TO BRING MUCH WARMER TEMPERATURES INTO AT
LEAST SOUTHERN PORTIONS OF THE AREA.
TEMPERATURES WILL REMAIN ABOVE FREEZING THROUGH THE NIGHT AND AT
LEAST EARLY THURSDAY...ESPECIALLY AREAS TO THE EAST ACROSS THE
NORTHERN FINGER LAKES AND TO THE EASTERN LAKE ONTARIO REGION.
ALTHOUGH THERE WILL BE SOME ACCUMULATING SNOW...THERE WILL BE SOME
LIQUID RAINFALL AS WELL. WILL CONTINUE TO MONITOR THE SITUATION
AND IF FORECAST CONFIDENCE INCREASES ON HIGHER RAINFALL AMOUNTS IT
IS POSSIBLE THAT FLOOD WATCHES WILL BE NEEDED FOR SOME AREAS.
HYDROLOGIC CONDITIONS ARE DISCUSSED IN THE LATEST FLOOD POTENTIAL
OUTLOOK (ESF) PRODUCT...AND THE RISK FOR FLOODING THROUGH LATE
WEEK IS DISCUSSED IN THE HAZARDOUS WEATHER OUTLOOK (HWO). IF THERE
IS GOING TO BE FLOODING DUE TO SNOW MELT THIS SPRING...THIS WILL
PROBABLY HAVE TO BE THE SYSTEM TO DO IT FOR THE BUFFALO
CREEKS...GENESEE...AND ALLEGHENY BASINS.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...WCH
NEAR TERM...APFFEL/WCH
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...APFFEL
MARINE...CHURCH/WCH
HYDROLOGY...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
946 PM CDT WED MAR 25 2015
.UPDATE...
ISSUED AT 945 PM CDT WED MAR 25 2015
THE FORECAST FOR THE REMAINDER OF THE NIGHT REMAINS ON TRACK AND
IN LINE WITH THE 23-01 UTC HRRR ITERATIONS AND INCOMING 00 UTC
NAM...DEVELOPING A BAND OF LIGHT SNOW ACROSS THE SOUTHWEST.
ALTHOUGH...THE NAM HAS THE MOST AMPLIFIED QPF FIELD...AND THUS DID
SHY AWAY FROM ITS OVERALL AMOUNTS.
UPDATE ISSUED AT 710 PM CDT WED MAR 25 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
INCREASE POPS ACROSS THE SOUTHWEST LATE TONIGHT GIVEN GOOD RUN TO
RUN CONSISTENCY AMONGST THE 20-22 UTC HRRR ITERATIONS OF A BAND
OF LIGHT SNOW DEVELOPING IN ASSOCIATION WITH THE BAROCLINIC ZONE
ON THE WESTERN PERIPHERY OF THE SURFACE RIDGE AXIS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 350 PM CDT WED MAR 25 2015
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE A WINDS
IN THE FAR EAST LATE THIS AFTERNOON...THEN PRECIPITATION CHANCES
LATE TONIGHT AND THURSDAY MORNING IN THE WEST ASSOCIATED WITH A
SHORTWAVE DROPPING ACROSS THIS AREA IN NORTHWEST FLOW.
CURRENTLY...WINDS GUSTING TO 43 MPH AT JAMESTOWN...WITH GUSTS TO
41 MPH AT CARRINGTON LAST HOUR. SOME PEAKS OF SUN PROBABLY ADDING
TO THE INCREASED MIXING. BUT GRADIENT WINDS WILL CONTINUE TO
SLACKEN AND FALL/RISE COUPLET HAS ALREADY PUSHED INTO THE RED
RIVER VALLEY. WILL KEEP THE ADVISORY GOING THROUGH THE 5 PM
EXPIRATION AND EXPECT WINDS TO DIMINISH BELOW CRITERIA BY THIS
TIME WITH A QUICK DROP OFF THIS EVENING. HIGH PRESSURE SITUATED
OVER EASTERN MONTANA WILL DRIFT EASTWARD INTO THE WESTERN DAKOTAS.
TONIGHT...NORTHWEST FLOW WILL QUICKLY DEVELOP OVER THE MONDAY
REGION TONIGHT. A IMPULSE MOVING THROUGH THE FLOW WILL INDUCE
SURFACE LOW PRESSURE OVER EASTERN MONTANA...WITH WEAK ISENTROPIC
UPGLIDE OVER WESTERN NORTH DAKOTA. THIS WILL RESULT IN A BAND OF
LIGHT PRECIPITATION DROPPING SOUTHEAST ACROSS WESTERN NORTH DAKOTA
LATE TONIGHT INTO THURSDAY MORNING. CURRENT BUFKIT SOUNDINGS
UTILIZING THE MAXIMUM WET BULB TEMPERATURE ALOFT INDICATES SNOW
TONIGHT AND A MIX OF RAIN AND SNOW THURSDAY. SNOW RATIOS ARE LOW
AND THUS WE ARE GETTING SNOW AMOUNTS OF AN INCH OR LESS FROM
AROUND TROTTERS SOUTHEAST THROUGH DICKINSON TO HETTINGER. SNOW IS
EXPECTED TO END BY MIDDAY THURSDAY. SHOULD BE WARMER THURSDAY WITH
MAINLY 30S EAST TO 40S SOUTHWEST.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 350 PM CDT WED MAR 25 2015
THE LONG TERM WILL BE CHARACTERIZED BY A PROGRESSIVE FLOW WITH
SEVERAL LOW PRESSURE SYSTEMS TRAVERSING THE FORECAST AREA.
THURSDAY NIGHT AND FRIDAY:
COOL HIGH PRESSURE WILL BE IN PLACE OVER THE EASTERN DAKOTAS
THURSDAY NIGHT. A WARM FRONT IS FORECAST TO APPROACH THE WESTERN
BORDER OF NORTH DAKOTA THURSDAY NIGHT...AND MOVE EASTWARD ACROSS THE
STATE ON FRIDAY. PRECIPITATION IS EXPECTED ALONG AND EITHER SIDE OF
THE WARM FRONT. THE WARM ADVECTION MOVING IN FROM THE WEST WILL BE
CHARACTERIZED BY A WARM LAYER ABOVE THE SURFACE LEADING/AHEAD OF THE
WARMING AT THE SURFACE. THIS WILL RESULT IN A CHANCE OF LIGHT SNOW
AHEAD OF THE FRONT...A NARROW BAND ALONG THE WARM FRONT WITH CHANCES
OF FREEZING RAIN...FOLLOWED BY CHANCES OF RAIN BEHIND THE WARM
FRONT. LOWS THURSDAY NIGHT SHOULD RANGE FROM THE TEENS EAST TO THE
LOWER 30S SOUTHWEST...WITH HIGHS FRIDAY FROM AROUND 40 EAST TO THE
LOWER 60S SOUTHWEST.
A WARM DAY SATURDAY WITH HIGHS IN THE UPPER 50S TO UPPER 60S. THE
APPROACH OF AN UPPER LEVEL LOW MOVING EAST ACROSS THE ROCKIES WILL
DEVELOP A SURFACE LOW THAT ENTERS WESTERN NORTH DAKOTA SATURDAY
AFTERNOON. THIS WILL BRING A SLIGHT CHANCE OF LIGHT RAIN TO THE WEST
SATURDAY AFTERNOON...AND A BETTER CHANCE OF LIGHT RAIN SATURDAY
NIGHT AS THE SYSTEM MOVES ACROSS THE AREA.
GENERALLY MILD AND DRY SUNDAY AND MONDAY...THEN THE APPROACH OF
ANOTHER SHORTWAVE MOVING EAST ACROSS THE ROCKIES WILL BRING CHANCES
OF PRECIPITATION TUESDAY INTO WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 945 PM CDT WED MAR 25 2015
VFR CEILINGS IN STRATUS WILL PREVAIL AT KJMS THROUGH
TONIGHT...POSSIBLY LOWERING TO MVFR THURSDAY MORNING AND IMPACTING
KMOT AND KBIS AS WELL. IFR CONDITIONS IN STRATUS AND A BAND OF
LIGHT SNOW IS POSSIBLE AT KISN AND KDIK LATE TONIGHT INTO EARLY
THURSDAY MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...TWH
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
711 PM CDT WED MAR 25 2015
.UPDATE...
ISSUED AT 710 PM CDT WED MAR 25 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
INCREASE POPS ACROSS THE SOUTHWEST LATE TONIGHT GIVEN GOOD RUN TO
RUN CONSISTENCY AMONGST THE 20-22 UTC HRRR ITERATIONS OF A BAND
OF LIGHT SNOW DEVELOPING IN ASSOCIATION WITH THE BAROCLINIC ZONE
ON THE WESTERN PERIPHERY OF THE SURFACE RIDGE AXIS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 350 PM CDT WED MAR 25 2015
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE A WINDS
IN THE FAR EAST LATE THIS AFTERNOON...THEN PRECIPITATION CHANCES
LATE TONIGHT AND THURSDAY MORNING IN THE WEST ASSOCIATED WITH A
SHORTWAVE DROPPING ACROSS THIS AREA IN NORTHWEST FLOW.
CURRENTLY...WINDS GUSTING TO 43 MPH AT JAMESTOWN...WITH GUSTS TO
41 MPH AT CARRINGTON LAST HOUR. SOME PEAKS OF SUN PROBABLY ADDING
TO THE INCREASED MIXING. BUT GRADIENT WINDS WILL CONTINUE TO
SLACKEN AND FALL/RISE COUPLET HAS ALREADY PUSHED INTO THE RED
RIVER VALLEY. WILL KEEP THE ADVISORY GOING THROUGH THE 5 PM
EXPIRATION AND EXPECT WINDS TO DIMINISH BELOW CRITERIA BY THIS
TIME WITH A QUICK DROP OFF THIS EVENING. HIGH PRESSURE SITUATED
OVER EASTERN MONTANA WILL DRIFT EASTWARD INTO THE WESTERN DAKOTAS.
TONIGHT...NORTHWEST FLOW WILL QUICKLY DEVELOP OVER THE MONDAY
REGION TONIGHT. A IMPULSE MOVING THROUGH THE FLOW WILL INDUCE
SURFACE LOW PRESSURE OVER EASTERN MONTANA...WITH WEAK ISENTROPIC
UPGLIDE OVER WESTERN NORTH DAKOTA. THIS WILL RESULT IN A BAND OF
LIGHT PRECIPITATION DROPPING SOUTHEAST ACROSS WESTERN NORTH DAKOTA
LATE TONIGHT INTO THURSDAY MORNING. CURRENT BUFKIT SOUNDINGS
UTILIZING THE MAXIMUM WET BULB TEMPERATURE ALOFT INDICATES SNOW
TONIGHT AND A MIX OF RAIN AND SNOW THURSDAY. SNOW RATIOS ARE LOW
AND THUS WE ARE GETTING SNOW AMOUNTS OF AN INCH OR LESS FROM
AROUND TROTTERS SOUTHEAST THROUGH DICKINSON TO HETTINGER. SNOW IS
EXPECTED TO END BY MIDDAY THURSDAY. SHOULD BE WARMER THURSDAY WITH
MAINLY 30S EAST TO 40S SOUTHWEST.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 350 PM CDT WED MAR 25 2015
THE LONG TERM WILL BE CHARACTERIZED BY A PROGRESSIVE FLOW WITH
SEVERAL LOW PRESSURE SYSTEMS TRAVERSING THE FORECAST AREA.
THURSDAY NIGHT AND FRIDAY:
COOL HIGH PRESSURE WILL BE IN PLACE OVER THE EASTERN DAKOTAS
THURSDAY NIGHT. A WARM FRONT IS FORECAST TO APPROACH THE WESTERN
BORDER OF NORTH DAKOTA THURSDAY NIGHT...AND MOVE EASTWARD ACROSS THE
STATE ON FRIDAY. PRECIPITATION IS EXPECTED ALONG AND EITHER SIDE OF
THE WARM FRONT. THE WARM ADVECTION MOVING IN FROM THE WEST WILL BE
CHARACTERIZED BY A WARM LAYER ABOVE THE SURFACE LEADING/AHEAD OF THE
WARMING AT THE SURFACE. THIS WILL RESULT IN A CHANCE OF LIGHT SNOW
AHEAD OF THE FRONT...A NARROW BAND ALONG THE WARM FRONT WITH CHANCES
OF FREEZING RAIN...FOLLOWED BY CHANCES OF RAIN BEHIND THE WARM
FRONT. LOWS THURSDAY NIGHT SHOULD RANGE FROM THE TEENS EAST TO THE
LOWER 30S SOUTHWEST...WITH HIGHS FRIDAY FROM AROUND 40 EAST TO THE
LOWER 60S SOUTHWEST.
A WARM DAY SATURDAY WITH HIGHS IN THE UPPER 50S TO UPPER 60S. THE
APPROACH OF AN UPPER LEVEL LOW MOVING EAST ACROSS THE ROCKIES WILL
DEVELOP A SURFACE LOW THAT ENTERS WESTERN NORTH DAKOTA SATURDAY
AFTERNOON. THIS WILL BRING A SLIGHT CHANCE OF LIGHT RAIN TO THE WEST
SATURDAY AFTERNOON...AND A BETTER CHANCE OF LIGHT RAIN SATURDAY
NIGHT AS THE SYSTEM MOVES ACROSS THE AREA.
GENERALLY MILD AND DRY SUNDAY AND MONDAY...THEN THE APPROACH OF
ANOTHER SHORTWAVE MOVING EAST ACROSS THE ROCKIES WILL BRING CHANCES
OF PRECIPITATION TUESDAY INTO WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 710 PM CDT WED MAR 25 2015
VFR CEILINGS IN STRATO-CUMULUS/STRATUS WILL PREVAIL AT
KMOT/KJMS/KBIS THIS EVENING AND TONIGHT...POSSIBLY LOWERING TO
MVFR THURSDAY MORNING. IFR CONDITIONS IN STRATUS AND A BAND OF
LIGHT SNOW IS POSSIBLE AT KISN AND KDIK LATE TONIGHT INTO EARLY
THURSDAY MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...TWH
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
520 PM CDT TUE MAR 24 2015
.UPDATE...
ISSUED AT 520 PM CDT TUE MAR 24 2015
QUICK UPDATE TO REFLECT THE LATEST RADAR TRENDS THROUGH 22
UTC...BLENDED TO THE 18-21 UTC HRRR ITERATIONS THROUGH TONIGHT WHICH
HAVE A GOOD HANDLE ON THE WRAP AROUND PRECIPITATION BAND SO FAR
EARLY THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 342 PM CDT TUE MAR 24 2015
LOW PRESSURE NEAR BISMARCK AT 20 UTC WILL TRACK NORTHEAST NEAR
DEVILS LAKE BY MID EVENING AND TO FAR NORTHEAST NORTH DAKOTA AFTER
MIDNIGHT. THE RISK OF FREEZING RAIN HAS ENDED...WITH RAIN/SNOW
EXPECTED FOR THE REMAINDER OF THE AFTERNOON AND MAINLY SNOW
TONIGHT.
STRONG WINDS CONTINUE OVER SOUTHWEST NORTH DAKOTA ON THE BACK SIDE
OF THE SYSTEM...EXPECTED TO DIMINISH BY THIS EVENING AS THE
STRONGEST GRADIENT MOVES INTO CENTRAL NORTH DAKOTA. COULD BE A FEW
HOURS OF NEAR ADVISORY CRITERIA IN THE CENTRAL LATE AFTERNOON TO
EARLY EVENING...BUT AS MIXING LAYER SHRINKS THIS EVENING THINK
GUSTINESS WILL DIMINISH. IT WILL REMAIN BREEZY TO WINDY THROUGH
THE NIGHT...WITH THE STRONGEST WINDS MOVING INTO THE JAMES RIVER
VALLEY TO THE TURTLE MOUNTAINS LATE TONIGHT INTO WEDNESDAY
MORNING. WITH THE STRONGEST WINDS ALOFT AND FALL RISE COUPLET HERE
ARRIVING AT THE DIURNAL MINIMUM FOR WINDS...HAVE HELD OFF ON
ISSUING AN ADVISORY. WILL BE MARGINAL THOUGH AND EVENING AND
OVERNIGHT SHIFT CAN CONTINUE TO MONITOR.
SNOW IS TAPERING OFF OVER FAR WESTERN NORTH DAKOTA AND WE HAVE
CANCELLED THE WINTER WEATHER ADVISORY FOR DIVIDE AND WILLIAMS
COUNTIES. SNOW CONTINUES ACROSS MUCH OF CENTRAL NORTH DAKOTA. THE
SNOW IS EXPECTED TO LIFT NORTH AND EAST TONIGHT. REPORTS SO FAR OF
1 TO 2 INCHES FROM AROUND WILLISTON TO STANLEY THIS AFTERNOON.
ANOTHER INCH OR TWO IS POSSIBLE FROM AROUND STANLEY TO KENMARE AND
SHERWOOD EAST THROUGH MINOT AND BOTTINEAU...RUGBY AND BELCOURT.
TOTAL SNOW AMOUNTS OF 3 TO 5 INCHES MAY BE REALIZED IN A FEW
LOCAL AREAS OF THE FAR NORTH CENTRAL...BUT EXPECT MOST AREAS TO BE
IN THE 1 TO 3 INCH RANGE. EXCEPT FOR THE NORTHWEST COUNTIES
MENTIONED ABOVE...WILL CONTINUE THE CURRENT ADVISORY OVER THE FAR
NORTH CENTRAL. MAIN THREATS WILL BE SLIPPERY ROADS AND REDUCED
VISIBILITIES IN SNOW AND BLOWING SNOW.
SNOW WILL TAPER OFF ACROSS THE FAR NORTH CENTRAL AND EAST CENTRAL
EARLY WEDNESDAY MORNING. OTHERWISE EXPECT A DRY BUT BREEZY TO
WINDY AND SEASONABLY COLD DAY WITH HIGHS MAINLY IN THE 30S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 342 PM CDT TUE MAR 24 2015
THE EARLY PORTION OF THE LONG TERM PERIOD...WEDNESDAY NIGHT THROUGH
SATURDAY...WILL FEATURE A 500MB RIDGE OVER THE WEST COAST THAT WILL
STRENGTHEN AND EXPAND EAST INTO THE ROCKIES.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT:
THIS WEST COAST RIDGE WILL KEEP A NORTHWEST FLOW OVER NORTH DAKOTA
AND ALLOW SOME UPPER LEVEL SHORTWAVE ENERGY IMPULSES TO MOVE
SOUTHEAST THROUGH THE FLOW. THIS UPPER LEVEL INSTABILITY WILL
ENHANCE SOME LOW LEVEL LIFTING OVER FAR WESTERN NORTH DAKOTA
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT - ON THE WESTERN EDGE OF
CANADIAN HIGH PRESSURE OVER THE EASTERN DAKOTAS. COOL WITH HIGHS IN
THE 30S AND 40S ACROSS THE REGION.
FRIDAY:
AS THE LARGE-SCALE RIDGE BUILDS AND EXPANDS...IT WILL PUSH A
STRONGER UPPER LEVEL SHORTWAVE EASTWARD ACROSS NORTH DAKOTA
ACCOMPANIED BY A WARM FRONT. CHANCES OF MAINLY LIGHT SNOW ALONG AND
AHEAD OF THE WARM FRONT...CHANGING TO RAIN BEHIND IT. LOOK FOR HIGHS
FROM THE 30S IN THE TURTLE MOUNTAINS AND JAMES VALLEY TO THE 50S IN
THE WEST.
SATURDAY THROUGH TUESDAY:
THE UPPER LEVEL RIDGE BREAKS DOWN SATURDAY...BUT A WARM DAY AHEAD OF
A SURFACE FRONTAL BOUNDARY THAT SHOULD MOVE ACROSS THE STATE
SATURDAY NIGHT. HIGHS SATURDAY IN THE 50S AND 60S.
PACIFIC HIGH PRESSURE FOLLOWS THE FRONTAL BOUNDARY WITH MILD
CONDITIONS - HIGHS IN THE 50S TO MID 60S SUNDAY THROUGH TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY)
ISSUED AT 519 PM CDT TUE MAR 24 2015
WIDESPREAD MVFR STRATUS WILL IMPACT ALL OF WESTERN AND CENTRAL
NORTH DAKOTA THROUGH WEDNESDAY MORNING. IFR CONDITIONS ARE FAVORED
IN SNOW AT KMOT THROUGH 07-08 UTC...POSSIBLY IMPACTING KBIS
THROUGH 01-03 UTC AND KJMS LATER TONIGHT. STRONG NORTHWEST WINDS
WITH GUSTS OF 25 TO 35 KTS WILL CONTINUE THIS EVENING AND TONIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 AM CDT WEDNESDAY FOR NDZ002>005-
010-011.
WIND ADVISORY UNTIL 6 PM MDT THIS EVENING FOR NDZ040-041-043-044.
&&
$$
UPDATE...AYD
SHORT TERM...TWH
LONG TERM...JV
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
701 PM EDT WED MAR 25 2015
.SYNOPSIS...
LOW PRESSURE CROSSES THE MIDDLE OHIO VALLEY THURSDAY MORNING. THIS
DRAGS A STRONG COLD FRONT THROUGH THE AREA MIDDAY AND AFTERNOON.
MUCH COLDER AIR DOMINATES THURSDAY NIGHT THROUGH SUNDAY MORNING.
&&
.NEAR TERM /UNTIL 11 PM THIS EVENING/...
SATELLITE TRENDS AND THE HRRR MODEL INDICATE THAT CLOUDS WILL NOT BE
VERY ABUNDANT LATE THIS AFTERNOON AND EARLY THIS EVENING. WILL
UPDATE THE FORECAST TO BETTER REFLECT THIS.
&&
.SHORT TERM /11 PM THIS EVENING THROUGH SATURDAY/...
COLD FRONT SHOULD BE EAST OF THE REGION AT THE BEGINNING OF THE
PERIOD. THIS FEATURE WILL CONTINUE TO PUSH EAST. HOWEVER...SURFACE
HIGH PRESSURE WILL TAKE AWHILE TO BUILD IN AS UPPER LEVEL TROF WILL
LAG BEHIND THE SURFACE FEATURE.
CURRENT THINKING IS THAT PRECIPITATION CHANCES WILL SLOWLY DECREASE
BEHIND THE FRONT AND THEN INCREASE LATE FRIDAY INTO FRIDAY NIGHT AS
THE UPPER TROF APPROACHES. PRECIP CHANCES SHOULD THEN DECREASE
FRIDAY NIGHT...WITH DRY CONDITIONS EXPECTED BY MID-DAY ON SATURDAY.
SINCE UPPER TROF DOES NOT ACTUALLY PUSH EAST UNTIL LATE FRIDAY NIGHT
INTO SATURDAY...MAY NOT HAVE HELD ONTO CHANCE POPS LONG ENOUGH. BUT
FUTURE SHIFTS WILL HAVE TO RE-EXAMINE THAT.
WITH COLDER SIR FILTERING IN THURSDAY NIGHT...EXPECT PRECIP WILL MIX
WITH...OR CHANGE TO SNOW ACROSS ALL...BUT THE SOUTHERN COALFIELDS.
THE AIRMASS WILL BE QUITE COLD FRO THIS TIME OF YEAR. BUT EXPECT
THE LOW-LEVEL TEMPS TO WARM ENOUGH FRIDAY AND SATURDAY,,,CAUSING THE
PRECIP TO CHANGE BACK TO RAIN.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ROLLER COASTER RIDE IN THE TEMP DEPARTMENT TO CONTINUE THRU THE
EXTENDED PERIODS. SURFACE HIGH AND A VERY DRY AIRMASS WILL ALLOW
FOR IDEAL RADIATIONAL COOLING SATURDAY NIGHT WITH MANY PLACES
DIPPING INTO THE TEENS. TRIED TO HIT THE TYPICAL COLD SPOTS HARD
WHILE KEEPING AREAS ALONG BIG RIVERS A FEW DEGREES HIGHER THAN
GUIDANCE SUGGESTS. A NICE REBOUND WILL BE REALIZED ON SUNDAY AMID WAA
ALOFT ON STRENGTHENING SW FLOW. A FAST MOVING COLD FRONT WILL
SLIDE THRU SUNDAY NIGHT WITH A CHANCE FOR SHOWERS. A WAVE MAY
DEVELOP IN THE TN VALLEY ON MONDAY WHICH WOULD KEEP THE RAIN
THREAT GOING ACROSS SW VA AND SE WV. TEMPS WILL COME BACK DOWN
BEHIND THE FRONT AS NW FLOW ALOFT BECOMES ESTABLISHED BEHIND A
CLIPPER SYSTEM EARLY TUESDAY...WITH A SMALL CHANCE FOR A SHOWER
AND SNOW SHOWER FOR THE N MOUNTAINS. UPPER HEIGHTS WILL QUICKLY
REBOUND MIDWEEK WITH DECENT WAA CRANKING ONCE AGAIN...AHEAD OF THE
NEXT FRONT. AS A RESULT...TEMPS SHOULD SPIKE INTO THE 70S ONCE
AGAIN LONG ABOUT WEDNESDAY.
&&
.AVIATION /00Z WEDNESDAY THROUGH MONDAY/...
VFR CONDITIONS CAN BE EXPECTED THIS EVENING. AS A SYSTEM APPROACHES
EARLY THURSDAY MORNING...AN MVFR CLOUD DECK WILL DEVELOP OVER
SOUTHEAST OHIO AND THE SOUTHEAST UPSLOPE COUNTIES OF THE MOUNTAINS.
AS THE LOW MOVES PAST DURING THE DAY ON THURSDAY...A COLD FRONT WILL
SWING ACROSS THE REGION PROVIDING RESTRICTIONS ALONG AND BEHIND THE
FRONT IN SHOWERS AND CLOUDS...AND POSSIBLY THUNDERSTORMS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z FRIDAY...
FORECAST CONFIDENCE: HIGH TONIGHT...MEDIUM THURSDAY.
ALTERNATE SCENARIOS: TIMING OF RESTRICTIONS IN CLOUDS AND
PRECIPITATION ON THURSDAY 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 20 21 22 23 00 01 02 03 04 05 06 07
EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
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 M 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 00Z FRIDAY...
IFR POSSIBLE IN CIGS BEHIND THE COLD FRONT THU NIGHT IN THE
MOUNTAINS. IFR ALSO POSSIBLE FRIDAY ACROSS NRN WV AND DOWN THROUGH
THE MOUNTAINS IN MIXED RAIN AND SNOW SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/TRM/30
NEAR TERM...RPY
SHORT TERM...JSH
LONG TERM...30
AVIATION...RPY
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
248 PM EDT TUE MAR 24 2015
.SYNOPSIS...
WARM FRONT LIFTS NORTH TONIGHT. COLD FRONT CROSSES THURSDAY. HIGH
PRESSURE SLOW TO TAKE CONTROL. MUCH COLDER AIR FOR FRIDAY AND
SATURDAY. NEXT COLD FRONT SUNDAY NIGHT/MONDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
FLOW AMPLIFIES THIS PERIOD...WITH WARM AIR PUSHING NWD W OF THE
MOUNTAINS...AND THE ASSOCIATED TIGHTENING PRESSURE GRADIENT
ENCOURAGING CAD WEDGE ON INCREASING SE FLOW E OF THE MOUNTAINS.
SPOTTY LIGHT RAIN WAS WORKING EWD INTO THE AREA FROM THE LOWER OH
VALLEY...N OF A WARM FRONT EDGING INTO SRN KENTUCKY. THIS SPOTTY
LIGHT RAIN WILL INCREASE IN COVERAGE SOMEWHAT AS IT PUSHES NWD
TONIGHT AHEAD OF THE ADVANCING WARM FRONT...WITH THE HELP OF AN
INITIAL UPPER LEVEL S/W TROUGH LIFTING THROUGH THE OHIO VALLEY.
AS THE S/W LIFTS THROUGH THE GREAT LAKES ON WED....THE COLD FRONT
ASSOCIATED WITH THE CORRESPONDING SFC LOW LOSES ITS PUSH...SO HAVE
JUST A MINIMAL CHANCE FOR SHOWERS TRAVERSING THE FCST AREA BENEATH
WEAK UPPER LEVEL RIDGING AHEAD OF THE NEXT S/W TROUGH...WELL
UPSTREAM WED AFTERNOON.
USED THE HRRR AND MET FOR TEMPERATURES TONIGHT WHICH WILL BECOME
NEARLY STEADY OVERNIGHT...PERHAPS A SLIGHT RISE W OF AND A SLIGHT
FALL E OF THE MOUNTAINS IN THE AMPLIFYING FLOW. BLENDED IN THE MET
AND BIAS CORRECTED MAV FOR A WARM WED AFTERNOON IN THE WARM SECTOR.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AN AREA OF LOW PRESSURE...WHICH SHOULD BE LOCATED NEAR ARKANSAS AT
THE BEGINNING OF THE PERIOD...WILL MOVE TO OHIO BY 12Z THURSDAY AND
THEN CONTINUE NORTHEASTWARD ACROSS NEW ENGLAND INTO THE ATLANTIC
OCEAN BY THURSDAY NIGHT. AS THIS FEATURE MOVES ACROSS PA...A COLD
FRONT WILL BE DRAGGED EASTWARD. CURRENT THINKING IS THE FRONT WILL
BE WEST OF OUR AREA AT 12Z...ALONG A CKB TO CRW TO JKL LINE AT
18Z...AND THEN BE EAST OF THE AREA AFTER 21Z.
HAVE THUNDER IN THE FORECAST FOR EARLY WEDNESDAY NIGHT...ACROSS OUR
SOUTHWESTERN COUNTIES. THE INSTABILITY SHOULD WANE AFTER SUNSET AND
EXPECT ANY STORMS WILL DISSIPATE BY 03Z. HOWEVER...THE THREAT OF
THUNDERSTORMS WILL REDEVELOP ACROSS THE AREA...ALONG AND EAST OF THE
COLD FRONT ON THURSDAY.
EVEN AS FRONT PUSHES EAST...AN UPPER LEVEL TROF WILL KEEP PRECIP
CHANCES IN THE FORECAST. THE TROF SHOULD PUSH EAST LATER FRIDAY/
FRIDAY NIGHT BRINGING PRECIPITATION CHANCES TO AN END IN MOST
LOCATIONS.
COLDER AIR WILL FILTER INTO THE AREA THURSDAY NIGHT...WITH LOWS
THURSDAY NIGHT ABOUT 15-20 DEGREES COLDER THAN THOSE EXPECTED
WEDNESDAY NIGHT. THE PRECIPITATION SHOULD MIX WITH...OR CHANGE TO
SNOW...ACROSS MUCH OF THE AREA...WITH SOME POSSIBLE LIGHT SNOW
ACCUMULATIONS ACROSS THE HIGHEST ELEVATIONS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
LONG RANGE MODELS CONTINUE TO BRING MID MINUS TEENS INTO THE CENTRAL
APPALACHIANS FOR THE WEEKEND AS A DEEP TROUGH TROUGH ALOFT CUTS IN.
WILL CONTINUE TO SIT ON THE LOW SIDE OF GUIDANCE NUMBERS AND
BELOW...ESPECIALLY INTO SATURDAY NIGHT WITH THE CLEARER SKIES AND
POTENTIAL FOR EFFICIENT RADIATIONAL COOLING. SATURDAY TEMPERATURES
WILL BE ON THE ORDER OF 20 DEGREES BELOW NORMAL. COLD FRONT COMES
THROUGH SUNDAY NIGHT/MONDAY WITH THE NEXT BATCH OF PRECIPITATION.
TEMPERATURES MODIFY OUT OF THE COLDER PATTERN FOR THE BEGINNING OF
NEXT WEEK AND APPROACH NORMAL LEVELS ONCE AGAIN.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
LIGHT RAIN AHEAD OF A WARM FRONT PUSHING NWD THROUGH THE AREA
TONIGHT WILL CAUSE LITTLE FLIGHT CAT RESTRICTIONS.
HOWEVER...MOISTENING AND STRENGTHENING SE FLOW ON THE E SLOPES OF
THE MOUNTAINS IS LIKELY TO BRING MVFR STRATOCU THERE OVERNIGHT
TONIGHT AND WED. A STRATOCU DECK MAY REACH THE OHIO RIVER FROM THE
W TOWARD THE END OF THE TAF PERIOD...BEFORE MIXING OUT WED AFTERNOON.
LIGHT NE SFC FLOW WILL VEER TO SE TONIGHT...AND THEN STRENGTHEN FROM
THE S WED...POSSIBLY BECOMING A BIT GUSTY...ESPECIALLY ON THE
RIDGES. LIGHT W FLOW ALOFT WILL BECOME SW OVERNIGHT AND INCREASE TO
MODERATE BY WED MORNING...AND BE MODERATE TO STRONG SW THROUGH
MIDDAY WED.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING THE LOWER CEILINGS DEVELOPING TONIGHT
ALONG THE EASTERN SLOPES COULD BE SLOWER DEVELOPING AROUND BKW THAN
FORECAST. THESE CIGS MAY GET CLOSE TO IFR OVERNIGHT INTO EARLY WED
MORNING. THERE IS UNCERTAINTY AS TO MVFR CEILINGS REACHING THE OHIO
RIVER MIDDAY WED. THE SPOTTY LIGHT RAIN COULD LEAD TO MVFR VSBYS
HERE AND THERE OVERNIGHT TONIGHT...BUT INCREASING FLOW SHOULD
PREVENT THIS FROM BECOMING TOO MUCH OF A FACTOR.
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
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
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 M
EKN CONSISTENCY H H H M H H H H H H H H
PKB CONSISTENCY M 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 CONDITIONS POSSIBLE IN SHOWERS AND POSSIBLE THUNDERSTORMS THU.
IFR POSSIBLE ACROSS NRN WV AND DOWN THROUGH THE MOUNTAINS THU NT IN
MIXED RAIN AND SNOW SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/TRM/26
NEAR TERM...TRM
SHORT TERM...JSH
LONG TERM...26
AVIATION...TRM
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
206 PM EDT TUE MAR 24 2015
.SYNOPSIS...
WARM FRONT LIFTS NORTH TONIGHT. COLD FRONT CROSSES THURSDAY. HIGH
PRESSURE SLOW TO TAKE CONTROL IN MUCH COLDER AIR FOR FRIDAY INTO THE
WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
FLOW AMPLIFIES THIS PERIOD...WITH WARM AIR PUSHING NWD W OF THE
MOUNTAINS...AND THE ASSOCIATED TIGHTENING PRESSURE GRADIENT
ENCOURAGING CAD WEDGE ON INCREASING SE FLOW E OF THE MOUNTAINS.
SPOTTY LIGHT RAIN WAS WORKING EWD INTO THE AREA FROM THE LOWER OH
VALLEY...N OF A WARM FRONT EDGING INTO SRN KENTUCKY. THIS SPOTTY
LIGHT RAIN WILL INCREASE IN COVERAGE SOMEWHAT AS IT PUSHES NWD
TONIGHT AHEAD OF THE ADVANCING WARM FRONT...WITH THE HELP OF AN
INITIAL UPPER LEVEL S/W TROUGH LIFTING THROUGH THE OHIO VALLEY.
AS THE S/W LIFTS THROUGH THE GREAT LAKES ON WED....THE COLD FRONT
ASSOCIATED WITH THE CORRESPONDING SFC LOW LOSES ITS PUSH...SO HAVE
JUST A MINIMAL CHANCE FOR SHOWERS TRAVERSING THE FCST AREA BENEATH
WEAK UPPER LEVEL RIDGING AHEAD OF THE NEXT S/W TROUGH...WELL
UPSTREAM WED AFTERNOON.
USED THE HRRR AND MET FOR TEMPERATURES TONIGHT WHICH WILL BECOME
NEARLY STEADY OVERNIGHT...PERHAPS A SLIGHT RISE W OF AND A SLIGHT
FALL E OF THE MOUNTAINS IN THE AMPLIFYING FLOW. BLENDED IN THE MET
AND BIAS CORRECTED MAV FOR A WARM WED AFTERNOON IN THE WARM SECTOR.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
FRONTAL ZONE HUNG UP IN OUR VICINITY WEDNESDAY AND WEDNESDAY NIGHT
AS ONE SURFACE LOW DEPARTS TO THE NE WHILE ANOTHER APPROACHES FROM
THE SW. HAVE GENERALLY CHANCE POPS ACROSS THE NORTH AND WEST...WITH
SLIGHT CHANCE ACROSS THE FAR SOUTH. ALSO HAVE SOME THUNDER MENTIONED
WEDNESDAY AFTERNOON...MAINLY IN THE OHIO RIVER VALLEY. STRONG COLD
FRONT SURGES THROUGH ON THURSDAY...WITH SHOWERS AND THUNDERSTORMS.
MODELS BEGINNING TO HINT AT A SECONDARY WAVE RIDING UP THE FRONT
DURING THE AFTERNOON AND EVENING WHICH MAY CAUSE IT TO HANG UP
ACROSS THE MOUNTAINS FOR A TIME. WEDNESDAY LOOKS WARM...WELL ABOVE
AVERAGE. ALTHOUGH NOT REAL DRASTIC...DO HAVE A NON-DIURNAL ON
THURSDAY...MAINLY IN SE OHIO.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
COLDER TREND SHAPING UP FOR THE EXTENDED BEHIND A COLD FRONT EXITING
THURSDAY NIGHT. DUE TO THE LINGERING NORTHWEST FLOW AND TEMPERATURES
DROPPING...SOME SCATTERED LIGHT SNOW IS POSSIBLE HEADING INTO FRIDAY
NIGHT IN THE LINGERING LOW LEVEL MOISTURE. A BRIEF HIGH PRESSURE
SYSTEM MODIFIES THE TEMPERATURES SUNDAY BACK TOWARDS NORMAL VALUES
FOR LATE MARCH. HOWEVER...ANOTHER LOW PRESSURE SYSTEM ROTATING
THROUGH BROAD UPPER LEVEL TROUGH PARKED OVER THE EASTERN THIRD OF
THE CONUS WILL KNOCK THEM BACK DOWN ONCE AGAIN. THE NEXT CHANCES
FOR PRECIPITATION ARRIVE WITH THIS SYSTEM IN THE SUNDAY
NIGHT/MONDAY TIME FRAME.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
LIGHT RAIN AHEAD OF A WARM FRONT PUSHING NWD THROUGH THE AREA
TONIGHT WILL CAUSE LITTLE FLIGHT CAT RESTRICTIONS.
HOWEVER...MOISTENING AND STRENGTHENING SE FLOW ON THE E SLOPES OF
THE MOUNTAINS IS LIKELY TO BRING MVFR STRATOCU THERE OVERNIGHT
TONIGHT AND WED. A STRATOCU DECK MAY REACH THE OHIO RIVER FROM THE
W TOWARD THE END OF THE TAF PERIOD...BEFORE MIXING OUT WED AFTERNOON.
LIGHT NE SFC FLOW WILL VEER TO SE TONIGHT...AND THEN STRENGTHEN FROM
THE S WED...POSSIBLY BECOMING A BIT GUSTY...ESPECIALLY ON THE
RIDGES. LIGHT W FLOW ALOFT WILL BECOME SW OVERNIGHT AND INCREASE TO
MODERATE BY WED MORNING...AND BE MODERATE TO STRONG SW THROUGH
MIDDAY WED.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING THE LOWER CEILINGS DEVELOPING TONIGHT
ALONG THE EASTERN SLOPES COULD BE SLOWER DEVELOPING AROUND BKW THAN
FORECAST. THESE CIGS MAY GET CLOSE TO IFR OVERNIGHT INTO EARLY WED
MORNING. THERE IS UNCERTAINTY AS TO MVFR CEILINGS REACHING THE OHIO
RIVER MIDDAY WED. THE SPOTTY LIGHT RAIN COULD LEAD TO MVFR VSBYS
HERE AND THERE OVERNIGHT TONIGHT...BUT INCREASING FLOW SHOULD
PREVENT THIS FROM BECOMING TOO MUCH OF A FACTOR.
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
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
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 M
EKN CONSISTENCY H H H M H H H H H H H H
PKB CONSISTENCY M 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 CONDITIONS POSSIBLE IN SHOWERS AND POSSIBLE THUNDERSTORMS THU.
IFR POSSIBLE ACROSS NRN WV AND DOWN THROUGH THE MOUNTAINS THU NT IN
MIXED RAIN AND SNOW SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/TRM/MZ
NEAR TERM...TRM
SHORT TERM...MZ
LONG TERM...26
AVIATION...TRM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1050 PM EDT WED MAR 25 2015
.SYNOPSIS...
A SLOW MOVING WARM FRONT WILL PUSH INTO PENNSYLVANIA EARLY
THURSDAY. LOW PRESSURE WILL TRACK ACROSS THE WESTERN PART OF THE
STATE LATE THURSDAY...DRAGGING A TRAILING COLD FRONT THROUGH THE
STATE. MUCH COOLER AND DRIER CONDITIONS WILL RETURN FOR FRIDAY
THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
11-3.9U IMAGERY AT 02Z SHOWS PTCLDY SKIES ACROSS THE WESTERN HALF
OF THE STATE...WHILE STRATUS PERSISTS OVER PORTIONS OF EASTERN PA.
STILL EXPECT PARTIAL CLEARING TONIGHT OVER THE EASTERN COUNTIES
BASED ON NEAR TERM MDLS SHOWING SERLY BLYR FLOW WEAKENING AND
VEERING FROM SE TO SOUTH.
BASED ON RADAR TRENDS...HAVE REMOVED MENTION OF LINGERING
SPRINKLES LATE THIS EVENING. FOCUS NOW ON DEEPENING TROUGH OVR
THE MISS VALLEY AND ASSOC SFC LOW LIFTING UP THE OHIO VALLEY. NR
TERM MDL DATA INDICATES A CHC OF SHOWERS ARRIVING ARND 12Z /ESP
OVR THE W MTNS/ UPON APPROACH OF LL JET AND ASSOC ISENTROPIC LIFT.
HAVE ADDED PATCHY FOG TO THE OVERNIGHT FCST OVR THE NW
MTNS...WHERE MOST SIG RAIN FELL EARLIER TODAY. LATEST RAP SFC RH
ALSO REMAINS NR 100 PCT IN THIS REGION OVERNIGHT. CONSALL BLENDED
WITH LATEST LAMP/RAP OUTPUT SUGGEST OVERNIGHT LOWS WILL RANGE FROM
THE 30S NORTH TO L40S SOUTH.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
LATEST MDL DATA TRACKS SFC LOW NORTHEAST ACROSS THE STATE DURING
THURSDAY. THIS TRACK WILL BRING A COLD RAIN TO THE NW COUNTIES...WHERE
GEFS/SREF OUTPUT SUPPORTS 100 PCT POPS. SFC WARM FRONT...WHICH
REMAINS HUNG UP WEST OF THE LAURELS THIS EVENING...WILL LIFT INTO
THE SOUTHERN AND EASTERN COUNTIES...RESULTING IN A MUCH WARMER AND
MAINLY DRY LATE AM/EARLY AFTN.
ACROSS THE SOUTHEAST HALF OF THE STATE...BEST CHC OF RAIN /NR 100
PCT BASED ON ENS DATA/ WILL COME DURING LATE AFTN/EARLY EVENING
WITH PASSAGE OF TRAILING COLD FRONT. MARGINALLY UNSTABLE
SOUNDINGS...COMBINED WITH LG SCALE FORCING IN ADVANCE OF MID LVL
SHORTWAVE...COULD SUPPORT A FEW TSRA ACROSS THE SOUTHERN COUNTIES
DURING THE LATE AFTN/EVENING.
AS LOW EXITS THE AREA...MDL SOUNDINGS BECOME COLD ENOUGH TO
SUPPORT A CHANGEOVER TO LGT SNOW/SNOW SHOWERS ACROSS THE NW MTNS
BY THU EVENING. FURTHER SOUTH...RESIDUAL MOISTURE ASCENDING THE
ALLEGHENIES SHOULD RESULT IN PRECIP ENDING AS -SHSN ACROSS THE
LAUREL HIGHLANDS THURSDAY NIGHT. A LIGHT ACCUM OF LESS THAN AN
INCH APPEARS LIKELY THU NIGHT FROM THE NW MTNS SOUTH ALONG THE
ALLEGHENIES TO SOMERSET CO.
THURSDAY SHOULD BE THE WARMEST DAY THIS SPRING OVER SOUTHERN
PA...WITH 18Z CONSALL MAXES IN THE 65-70F RANGE ACROSS THE
SOUTHERN VALLEYS NEAR THE MD BORDER. STRONG WINDS ALOFT WILL MIX
TO GROUND LVL IN THE WARM SECTOR ACROSS SOUTHERN PA. BUFKIT
SOUNDINGS SUPPORT GUSTS NR 30KTS ACROSS THE S TIER DURING THE AFTN
AND EARLY EVENING.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
DEEPENING BUT PROGRESSIVE UPPER TROF WILL BE MOVING EAST ACROSS
THE MID ATLANTIC STATES EARLY IN THE LONG TERM PERIOD. SIGNIFICANT
PRECIPITATION ASSOCIATED WITH THIS TROF SHOULD HAVE CONCLUDED BY
DAYTIME FRIDAY...BUT LINGERING SHOWERS ARE POSSIBLE INTO THE DAY
AS THE PUSH OF THE UPPER TROF HAS SLOWED A BIT IN RECENT GUIDANCE.
AT THE SFC...EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD INTO THE
REGION STARTING LATER FRIDAY WITH SEVERAL DRY DAYS INTO THE
WEEKEND.
THE DEEPNESS OF THIS UPPER TROF WILL BRING ANOTHER SHOT
UNSEASONABLY COLD AIR INTO THE REGION...ESPECIALLY NOTICEABLE
AFTER A COUPLE DAYS OF MORE SPRING LIKE CONDS WED AND THUR.
TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL OVER THE
WEEKEND.
A COMPARATIVELY WEAKER NRN STREAM WAVE WILL MOVE ACROSS THE UPPER
GREAT LAKES REGION AND TOWARDS THE NORTHEAST LATE SUNDAY INTOMONDAY.
THIS WILL CONTINUE THE CHILLY TEMPS AS WELL AS BRING THE CHANCE
FOR MORE SNOW SHOWERS.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
LLWS WILL IMPACT THE WRN TAFS THIS MORNING IN ASSOC WITH STRONG
SLY LLJ. -RA WILL SHIFT NEWD ACROSS THE REMAINDER OF THE AIRSPACE
BTWN 15-17Z WITH PREDOMINATELY VFR TO MVFR CONDITIONS EXPECTED.
CIGS AND VSBYS SHOULD TREND TO THE DOWNSIDE AFT 00Z WITH
WIDESPREAD MVFR TO IFR CONDITIONS FCST IN -RADZ AND FOG/MIST
TONIGHT INTO THURSDAY MORNING.
OUTLOOK...
THU...IFR/MVFR EARLY BCMG MVFR/VFR IN THE AFTN WITH PERIODS OF
RAIN SHOWERS. TSTMS ARE POSSIBLE OVER SOUTHERN AND EASTERN
AIRFIELDS.
THU NGT...RAIN CHANGING TO SNOW ACROSS THE NW AIRSPACE WITH IFR
AND MVFR OVER THE WRN 1/3. MVFR TO VFR CENTRAL AND EAST.
FRI-SAT...MVFR/IFR WITH SNOW SHOWERS NORTH/WEST. VFR TO MVFR CENTRAL
AND EAST WITH SCHC OF -SHRA.
SUN...NO SIG WX/VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DEVOIR/FITZGERALD
NEAR TERM...FITZGERALD
SHORT TERM...FITZGERALD/CERU
LONG TERM...DEVOIR/GARTNER
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1016 PM EDT WED MAR 25 2015
.SYNOPSIS...
SOUTHERLY FLOW WILL GRADUALLY INCREASE AHEAD OF AN APPROACHING COLD
FRONT TONIGHT THROUGH THURSDAY. THE COLD FRONT WILL CROSS THE
WESTERN CAROLINAS AND NORTHEAST GEORGIA THURSDAY NIGHT...MAINLY
DURING THE EVENING HOURS. A TRAILING UPPER LEVEL DISTURBANCE WILL
THEN CROSS THE AREA FRIDAY THROUGH FRIDAY NIGHT. DRY AND COOL HIGH
PRESSURE WILL SETTLE IN OVER THE WEEKEND. A LOW PRESSURE CLIPPER
SYSTEM AND ASSOCIATED COLD FRONT WILL PASS OVER THE REGION FROM THE
NORTHWEST AROUND THE START OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
EVENING UPDATE...POPS WERE BUMPED DOWN OVERNIGHT BASED ON LATEST REG
RADAR COMP AND CAMPOP OUTPUT. THE HIRES MODELS ARE OVERDONE WITH
PRECIP COVERAGE OVERNIGHT EXCEPT PERHAPS THE RAP WHICH WAS FOLLOWED
MORE CLOSELY WITH THE TRENDS. QPF AMOUNTS WERE ALSO ADJ DOWN AS
FORCING WILL REMAIN WEAK AS WEDGE BREAKS DOWN AND H85 FLOW VEERS
THROUGH DAYBREAK. WIDESPREAD ADJS WERE MADE TO MIN TEMPS AS WELL
WITH SOME LOCALES ALREADY AT THEIR FCST/D MINS AND OTHER AREAS A CAT
OR SO ABOVE THE FCST CURVE.
AT 730 PM EDT...UPDATED THE POPS GRIDS WITH A LOWERING TREND MAINLY
FOR LATER THIS EVENING. HOURLY TEMPS WERE ADJ UP IN THE UPSTATE AND
SRN NC PIEDMONT WITH THE LAST BIT OF DIFFERENTIAL HEATING SHOWING
UP. SKY COVER REMAINS TRICKY THIS EVENING AND THROUGH THE OVERNIGHT
ACROSS MOST OF THE HIGHER TERRAIN AND THE FAR SRN ZONES...BUT FOR
NOW HAVE MADE A GENERAL INCREASE IN COVERAGE ACROSS THE SOUTH BASED
ON CONTINUED LLVL MOISTURE FLUX.
AT 530 PM EDT...UPDATED THE GRIDS TO ACCOUNT FOR CHANGING CLOUD
COVER AND POCKETS OF DIFFERENTIAL HEATING. TRICKY SKY EVOLUTION WITH
DRIER AIR MIXING IN FROM THE SOUTH AND THIN WEAK BANDS OF -RA/DZ
PUSHING NORTH WITHIN SE/LY H85 FLOW. SFC WEDGE IS HOLDING STRONG FOR
NOW...SO WILL STAY MOSTLY CLOUDY MOST LOCALES NON/MTNS. THE MTN SKY
COVER WAS REDUCED SIGFNTLY WITH MODERATELY DEEP CU DIMINISHING WITH
LOSS OF HEATING.
AT 220 PM...HIGH PRESSURE REMAINS WEAKLY WEDGED ACROSS THE AREA WITH
THE PARENT HIGH WELL OFFSHORE. WEAK ISENTROPIC UPGLIDE OVER THE CAD
AREA CONTINUES TO PRODUCE A FEW SHOWERS. HOWEVER..THE LATE MARCH SUN
HAS ERODED THE CAD OVER THE LOWER PIEDMONT AREAS AND THE WESTERN
MOUNTAINS HAVE SEEN PARTIAL SUNSHINE ALL DAY. SOME IMPROVEMENT IN
THE LOW CLOUDINESS WILL CONTINUE ACROSS THE UPSTATE AND NE GA THIS
AFTERNOON AND RADAR INDICATES THAT PASSING SHOWERS WILL OCCUR SOME
AREAS.
FOR THE OVERNIGHT...CLOUDS WILL THICKEN AND LOWER AS THE BOUNDARY
LAYER COOLS. ALSO EXPECT THAT REAS OF LIGHT RAIN/DRIZZLE/FOG WILL
DEVELOP AS LOW LEVEL MOISTURE REMAINS ABUNDANT ALONG WITH WEAK
ISENTROPIC UPGLIDE. TEMPS WILL REMAIN MILD AND ABOVE CLIMO OVERNIGHT.
ON THU...THE ISENTROPIC UPGLIDE WILL BE CUT OFF IN THE MORNING AS
WINDS VEER TO THE SW AHEAD OF AN APPROACHIGN COLD FRONT. PARTIAL
CLEARING SHOULD OCCUR AND WITH THE INCREASING SUNSHINE MAX TEMPS
SHOULD REACH WELL INTO THE 70S EAST OF THE MOUNTAINS WITH 60S TO
AROUND 70 MOUNTAIN LOCATIONS. LOOKS LIKE THE FRONT WILL NOT REACH
THE WESTERN MOUNTAINS UNTIL AROUND 00Z SO SHOWER/THUNDERSTORM
CHANCES WILL BE ON THE LOW THROUGHOUT THE DAY WITH HIGHEST POPS
MOUNTAINS DURING THE LATE AFTERNOON.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 255 PM WEDNESDAY...GUIDANCE IN PRETTY GOOD AGREEMENT ON THE WX
PATTERN THRU THE SHORT RANGE. THE FIRST IN A SERIES OF SHORT WAVES
CROSSES THE AREA THU NITE IN THE SWLY FLOW ALOFT AHEAD OF A
DEEPENING TROF OVER THE MS RIVER VALLEY. THE TROF AXIS MOVES TO THE
WRN CWFA BORDER FRI AS A SHORT WAVE ROUNDS THE BASE OF THE TROF. THE
TROF AXIS MOVES INTO THE CWFA FRI NITE...THEN EAST OF THE AREA SAT
AS YET ANOTHER SHORT WAVE DIVES INTO THE AREA THRU THE TROF.
AT THE SFC...A COLD FRONT SLOWLY CROSSES THE AREA THU NITE AS WEAK
WAVES OF LOW PRESSURE FORM ALONG THE FRONT. MOST OF THE PRECIP WILL
BE BEHIND THE FRONT WITH SOME TSRA POSSIBLE...MAINLY OVER THE WRN
CWFA WHERE ANY WEAK INSTABILITY CAN COMBINE WITH THE FORCING TO
BREAK THE MID LEVEL CAP SEEN IN FCST SOUNDINGS. LOWS WILL BE 5 TO 10
DEGREES ABOVE NORMAL.
FRIDAY THRU FRIDAY NIGHT...ONE OF THE WAVES DEVELOPING ALONG THE
FRONT STRENGTHENS AS IT REACHES THE ATLANTIC COAST...HELPING KEEP
COPIOUS LOW LEVEL MOISTURE ACROSS THE AREA. THIS WILL COMBINE WITH
INSTABILITY DEVELOPING AS COLD MID LEVEL AIR MOVES OVERHEAD WITH THE
TROF TO PRODUCE THE CHC OF SHRA OUTSIDE OF THE MTNS. ALTHOUGH
GUIDANCE AGREES ON THIS SCENARIO...THEY DO NOT AGREE ON THE BEST
LOCATIONS AND TIMING FOR THE SHRA TO DEVELOP. THEREFORE...HAVE
LIMITED POP TO SLIGHT CHC FOR NOW. THE SHRA MOVE EAST ACROSS THE
AREA AND EXIT/DISSIPATE LATE FRI NITE. ACROSS THE MTNS HOWEVER...
GUIDANCE IS IN GOOD AGREEMENT ON ELEVATION DEPENDENT SNOW SHOWERS
FRI WITH SNOW LEVELS FALLING FRI NITE. THERE COULD BE A LIGHT
ACCUMULATION ACROSS THE USUAL HIGH ELEVATION AREAS BY THE TIME THE
SNOW SHOWERS END EARLY SAT. HIGHS FRI WILL BE NEARLY 10 DEGREES
BELOW NORMAL WITH LOWS FRI NITE 5 TO 10 DEGREES BELOW NORMAL.
SAT WILL BE DRY WITH CLEARING SKIES. HIGHS WILL BE 10 TO 15 DEGREES
BELOW NORMAL.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AT 230 PM EDT WEDNESDAY...ON SATURDAY EVENING...A MEAN UPPER TROUGH
WILL BE OVER THE EASTERN HALF OF THE NATION...WITH AN UPPER RIDGE
OVER THE WESTERN HALF. THE PATTERN FLATTENS OUT BY WEDNESDAY...WITH
ZONAL UPPER FLOW OVER THE SOUTHERN TIER OF STATES.
AT THE SURFACE...DRY HIGH PRESSURE WILL BE CENTERED OVER THE CENTRAL
APPALACHIANS ON SUNDAY. THIS HIGH SETTLES SOUTH TO GA BY MONDAY. A
COLD FRONT EXTENDING FROM EASTERN CANADA TO THE MID MS RIVER VALLEY
AND S PLAINS ON MONDAY WILL DROP SE ACROSS THE CAROLINAS ON
TUESDAY...WHILE THE WESTERN PORTION MOVES N AS A WARM FRONT INTO THE
MID MS RIVER VALLEY. ON WEDNESDAY THE SURFACE RIDGE MOVES OFF THE
COAST...AND GULF INFLOW INCREASES INTO THE SOUTHERN APPALACHIANS.
PRECIPITATION CHANCES MONDAY WILL BE BEST IN THE MOUNTAINS AS THE
COLD FRONT APPROACHES FORM THE NW...AND WILL BE LOWER IN THE LEE LOW
LEVEL FLOW TAKES ON A WESTERLY DOWNSLOPE FLOW COMPONENT ON TUESDAY.
PRECIPITATION CHANCES WILL INCREASE AGAIN ON WEDNESDAY AHEAD OF
ANOTHER COLD FRONT CROSSING THE GREAT LAKES AND MID MS RIVER VALLEY.
TEMPERATURES WILL STAR OUT AROUND 10 DEGREES ABOVE NORMAL ON SUNDAY
IN A COLD AIR MASS....WARMING TO NEAR NORMAL MONDAY IN ADVANCE OF
THE NEXT FRONT...AND REMAINING THERE THROUGH WEDNESDAY IN DOWNSLOPE
WARMING BEHIND THE FRONT AND WARM ADVECTION IN ADVANCE OF THE NEXT
FRONT.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
AT KCLT...LLVL CLOUDS IN THE MVFR RANGE WILL PERSIST THIS EVENING
WITH PERHAPS TEMPO VFR DRY AIR MIXING IN FROM THE SOUTH BEFORE
MIDNIGHT. THE SFC WEDGE WILL BEGIN TO BREAKDOWN THROUGH THE OVERNIGHT
WITH LLVL MOIST FLOW CONTINUING OFF THE ATL...THUS A LOWERING OF
CIGS INTO IFR/LIFR WILL DEVELOP AFT 06Z OR SO AND REMAIN THROUGH DAT
BREAK WITH A GRADUAL IMPROVEMENT INTO MVFR/VFR THROUGH NOON. SOME
LOWERING OF VSBY INTO MVFR IS ALSO POSSIBLE OVERNIGHT WITH WEAK
LINES OF -RA/DZ IN THE VICINITY BTW 03Z-09Z. WINDS WILL SHIFT AND
REMAIN SW/LY AFT 15Z WITH LOW END GUSTS POSSIBLE BY MID AFTERNOON IN
FAIRLY DEEP MIXING.
ELSEWHERE...SIMILAR TAF EVOLUTIONS TO THE KCLT TAF. EXPECT A
LOWERING OF CIGS WITH WEDGE BREAKDOWN AFTER MIDNIGHT. NOT MUCH OF A
VSBY THREAT...MAINLY MVFR OVERNIGHT...BUT THE UPSTATE COULD SEE IFR
WITH THE RECENT PRECIP. A GRADUAL IMPROVEMENT IN FLIGHT CONDS AFT 15Z
THROUGH NOON...WITH VFR EXPECTED IN THE AFTERNOON ALL SITES. WINDS
WILL SHIFT AND REMAIN SW/LY AFT 14Z/15Z WITH LOW/MODERATE GUSTS
POSSIBLE BY MID/AFTERNOON.
OUTLOOK...A COLD FRONT WILL CROSS THE AREA THU NIGHT ALONG WITH
RESTRICTIONS DUE TO SHOWERS AND THUNDERSTORMS. SOME IMPROVING
CONDITIONS ARE LIKELY BEHIND THE FRONT ON FRIDAY BUT SCATTERED
SHOWERS WILL CONTINUE TO PRODUCE SOME RESTRICTIONS. HIGH PRESSURE
WILL BUILD OVER THE REGION BEGINNING FRIDAY NIGHT PRODUCING VFR
CONDITIONS.
CONFIDENCE TABLE...
02-08Z 08-14Z 14-20Z 20-00Z
KCLT MED 74% HIGH 85% MED 72% HIGH 100%
KGSP HIGH 81% HIGH 87% MED 62% HIGH 100%
KAVL MED 77% MED 78% HIGH 81% HIGH 100%
KHKY MED 76% HIGH 87% MED 68% HIGH 100%
KGMU MED 76% MED 75% MED 66% HIGH 100%
KAND MED 79% MED 76% MED 68% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MINIMUM TEMPERATURES FOR MARCH 28TH...
GSP 26 1982
CLT 25 1982
AVL 11 1887
RECORD MINIMUM TEMPERATURES FOR MARCH 29TH...
GSP 26 1899
CLT 26 2013
AVL 19 1982
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...LG/SBK
SHORT TERM...RWH
LONG TERM...JAT
AVIATION...SBK
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1015 PM EDT WED MAR 25 2015
.SYNOPSIS...
SOUTHERLY FLOW WILL GRADUALLY INCREASE AHEAD OF AN APPROACHING COLD
FRONT TONIGHT THROUGH THURSDAY. THE COLD FRONT WILL CROSS THE
WESTERN CAROLINAS AND NORTHEAST GEORGIA THURSDAY NIGHT...MAINLY
DURING THE EVENING HOURS. A TRAILING UPPER LEVEL DISTURBANCE WILL
THEN CROSS THE AREA FRIDAY THROUGH FRIDAY NIGHT. DRY AND COOL HIGH
PRESSURE WILL SETTLE IN OVER THE WEEKEND. A LOW PRESSURE CLIPPER
SYSTEM AND ASSOCIATED COLD FRONT WILL PASS OVER THE REGION FROM THE
NORTHWEST AROUND THE START OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
EVENING UPDATE...POPS WERE BUMPED DOWN OVERNIGHT BASED ON LATEST REG
RADAR COMP AND CAMPOP OUTPUT. THE HIRES MODELS ARE OVERDONE WITH
PRECIP COVERAGE OVERNIGHT EXPECT PERHAPS THE RAP WHICH WAS FOLLOWED
MORE CLOSELY WITH THE TRENDS. QPF AMOUNTS WERE ALSO ADJ DOWN AS
FORCING WILL REMAIN WEAK AS WEDGE BREAKS DOWN AND H85 FLOW VEERS
THROUGH DAYBREAK. WIDESPREAD ADJS WERE MADE TO MIN TEMPS AS WELL
WITH SOME LOCALES ALREADY AT THEIR FCST/D MINS AND OTHER AREAS A CAT
OR SO ABOVE THE FCST CURVE.
AT 730 PM EDT...UPDATED THE POPS GRIDS WITH A LOWERING TREND MAINLY
FOR LATER THIS EVENING. HOURLY TEMPS WERE ADJ UP IN THE UPSTATE AND
SRN NC PIEDMONT WITH THE LAST BIT OF DIFFERENTIAL HEATING SHOWING
UP. SKY COVER REMAINS TRICKY THIS EVENING AND THROUGH THE OVERNIGHT
ACROSS MOST OF THE HIGHER TERRAIN AND THE FAR SRN ZONES...BUT FOR
NOW HAVE MADE A GENERAL INCREASE IN COVERAGE ACROSS THE SOUTH BASED
ON CONTINUED LLVL MOISTURE FLUX.
AT 530 PM EDT...UPDATED THE GRIDS TO ACCOUNT FOR CHANGING CLOUD
COVER AND POCKETS OF DIFFERENTIAL HEATING. TRICKY SKY EVOLUTION WITH
DRIER AIR MIXING IN FROM THE SOUTH AND THIN WEAK BANDS OF -RA/DZ
PUSHING NORTH WITHIN SE/LY H85 FLOW. SFC WEDGE IS HOLDING STRONG FOR
NOW...SO WILL STAY MOSTLY CLOUDY MOST LOCALES NON/MTNS. THE MTN SKY
COVER WAS REDUCED SIGFNTLY WITH MODERATELY DEEP CU DIMINISHING WITH
LOSS OF HEATING.
AT 220 PM...HIGH PRESSURE REMAINS WEAKLY WEDGED ACROSS THE AREA WITH
THE PARENT HIGH WELL OFFSHORE. WEAK ISENTROPIC UPGLIDE OVER THE CAD
AREA CONTINUES TO PRODUCE A FEW SHOWERS. HOWEVER..THE LATE MARCH SUN
HAS ERODED THE CAD OVER THE LOWER PIEDMONT AREAS AND THE WESTERN
MOUNTAINS HAVE SEEN PARTIAL SUNSHINE ALL DAY. SOME IMPROVEMENT IN
THE LOW CLOUDINESS WILL CONTINUE ACROSS THE UPSTATE AND NE GA THIS
AFTERNOON AND RADAR INDICATES THAT PASSING SHOWERS WILL OCCUR SOME
AREAS.
FOR THE OVERNIGHT...CLOUDS WILL THICKEN AND LOWER AS THE BOUNDARY
LAYER COOLS. ALSO EXPECT THAT REAS OF LIGHT RAIN/DRIZZLE/FOG WILL
DEVELOP AS LOW LEVEL MOISTURE REMAINS ABUNDANT ALONG WITH WEAK
ISENTROPIC UPGLIDE. TEMPS WILL REMAIN MILD AND ABOVE CLIMO OVERNIGHT.
ON THU...THE ISENTROPIC UPGLIDE WILL BE CUT OFF IN THE MORNING AS
WINDS VEER TO THE SW AHEAD OF AN APPROACHIGN COLD FRONT. PARTIAL
CLEARING SHOULD OCCUR AND WITH THE INCREASING SUNSHINE MAX TEMPS
SHOULD REACH WELL INTO THE 70S EAST OF THE MOUNTAINS WITH 60S TO
AROUND 70 MOUNTAIN LOCATIONS. LOOKS LIKE THE FRONT WILL NOT REACH
THE WESTERN MOUNTAINS UNTIL AROUND 00Z SO SHOWER/THUNDERSTORM
CHANCES WILL BE ON THE LOW THROUGHOUT THE DAY WITH HIGHEST POPS
MOUNTAINS DURING THE LATE AFTERNOON.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 255 PM WEDNESDAY...GUIDANCE IN PRETTY GOOD AGREEMENT ON THE WX
PATTERN THRU THE SHORT RANGE. THE FIRST IN A SERIES OF SHORT WAVES
CROSSES THE AREA THU NITE IN THE SWLY FLOW ALOFT AHEAD OF A
DEEPENING TROF OVER THE MS RIVER VALLEY. THE TROF AXIS MOVES TO THE
WRN CWFA BORDER FRI AS A SHORT WAVE ROUNDS THE BASE OF THE TROF. THE
TROF AXIS MOVES INTO THE CWFA FRI NITE...THEN EAST OF THE AREA SAT
AS YET ANOTHER SHORT WAVE DIVES INTO THE AREA THRU THE TROF.
AT THE SFC...A COLD FRONT SLOWLY CROSSES THE AREA THU NITE AS WEAK
WAVES OF LOW PRESSURE FORM ALONG THE FRONT. MOST OF THE PRECIP WILL
BE BEHIND THE FRONT WITH SOME TSRA POSSIBLE...MAINLY OVER THE WRN
CWFA WHERE ANY WEAK INSTABILITY CAN COMBINE WITH THE FORCING TO
BREAK THE MID LEVEL CAP SEEN IN FCST SOUNDINGS. LOWS WILL BE 5 TO 10
DEGREES ABOVE NORMAL.
FRIDAY THRU FRIDAY NIGHT...ONE OF THE WAVES DEVELOPING ALONG THE
FRONT STRENGTHENS AS IT REACHES THE ATLANTIC COAST...HELPING KEEP
COPIOUS LOW LEVEL MOISTURE ACROSS THE AREA. THIS WILL COMBINE WITH
INSTABILITY DEVELOPING AS COLD MID LEVEL AIR MOVES OVERHEAD WITH THE
TROF TO PRODUCE THE CHC OF SHRA OUTSIDE OF THE MTNS. ALTHOUGH
GUIDANCE AGREES ON THIS SCENARIO...THEY DO NOT AGREE ON THE BEST
LOCATIONS AND TIMING FOR THE SHRA TO DEVELOP. THEREFORE...HAVE
LIMITED POP TO SLIGHT CHC FOR NOW. THE SHRA MOVE EAST ACROSS THE
AREA AND EXIT/DISSIPATE LATE FRI NITE. ACROSS THE MTNS HOWEVER...
GUIDANCE IS IN GOOD AGREEMENT ON ELEVATION DEPENDENT SNOW SHOWERS
FRI WITH SNOW LEVELS FALLING FRI NITE. THERE COULD BE A LIGHT
ACCUMULATION ACROSS THE USUAL HIGH ELEVATION AREAS BY THE TIME THE
SNOW SHOWERS END EARLY SAT. HIGHS FRI WILL BE NEARLY 10 DEGREES
BELOW NORMAL WITH LOWS FRI NITE 5 TO 10 DEGREES BELOW NORMAL.
SAT WILL BE DRY WITH CLEARING SKIES. HIGHS WILL BE 10 TO 15 DEGREES
BELOW NORMAL.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AT 230 PM EDT WEDNESDAY...ON SATURDAY EVENING...A MEAN UPPER TROUGH
WILL BE OVER THE EASTERN HALF OF THE NATION...WITH AN UPPER RIDGE
OVER THE WESTERN HALF. THE PATTERN FLATTENS OUT BY WEDNESDAY...WITH
ZONAL UPPER FLOW OVER THE SOUTHERN TIER OF STATES.
AT THE SURFACE...DRY HIGH PRESSURE WILL BE CENTERED OVER THE CENTRAL
APPALACHIANS ON SUNDAY. THIS HIGH SETTLES SOUTH TO GA BY MONDAY. A
COLD FRONT EXTENDING FROM EASTERN CANADA TO THE MID MS RIVER VALLEY
AND S PLAINS ON MONDAY WILL DROP SE ACROSS THE CAROLINAS ON
TUESDAY...WHILE THE WESTERN PORTION MOVES N AS A WARM FRONT INTO THE
MID MS RIVER VALLEY. ON WEDNESDAY THE SURFACE RIDGE MOVES OFF THE
COAST...AND GULF INFLOW INCREASES INTO THE SOUTHERN APPALACHIANS.
PRECIPITATION CHANCES MONDAY WILL BE BEST IN THE MOUNTAINS AS THE
COLD FRONT APPROACHES FORM THE NW...AND WILL BE LOWER IN THE LEE LOW
LEVEL FLOW TAKES ON A WESTERLY DOWNSLOPE FLOW COMPONENT ON TUESDAY.
PRECIPITATION CHANCES WILL INCREASE AGAIN ON WEDNESDAY AHEAD OF
ANOTHER COLD FRONT CROSSING THE GREAT LAKES AND MID MS RIVER VALLEY.
TEMPERATURES WILL STAR OUT AROUND 10 DEGREES ABOVE NORMAL ON SUNDAY
IN A COLD AIR MASS....WARMING TO NEAR NORMAL MONDAY IN ADVANCE OF
THE NEXT FRONT...AND REMAINING THERE THROUGH WEDNESDAY IN DOWNSLOPE
WARMING BEHIND THE FRONT AND WARM ADVECTION IN ADVANCE OF THE NEXT
FRONT.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
AT KCLT...LLVL CLOUDS IN THE MVFR RANGE WILL PERSIST THIS EVENING
WITH PERHAPS TEMPO VFR DRY AIR MIXING IN FROM THE SOUTH BEFORE
MIDNIGHT. THE SFC WEDGE WILL BEGIN TO BREAKDOWN THROUGH THE OVERNIGHT
WITH LLVL MOIST FLOW CONTINUING OFF THE ATL...THUS A LOWERING OF
CIGS INTO IFR/LIFR WILL DEVELOP AFT 06Z OR SO AND REMAIN THROUGH DAT
BREAK WITH A GRADUAL IMPROVEMENT INTO MVFR/VFR THROUGH NOON. SOME
LOWERING OF VSBY INTO MVFR IS ALSO POSSIBLE OVERNIGHT WITH WEAK
LINES OF -RA/DZ IN THE VICINITY BTW 03Z-09Z. WINDS WILL SHIFT AND
REMAIN SW/LY AFT 15Z WITH LOW END GUSTS POSSIBLE BY MID AFTERNOON IN
FAIRLY DEEP MIXING.
ELSEWHERE...SIMILAR TAF EVOLUTIONS TO THE KCLT TAF. EXPECT A
LOWERING OF CIGS WITH WEDGE BREAKDOWN AFTER MIDNIGHT. NOT MUCH OF A
VSBY THREAT...MAINLY MVFR OVERNIGHT...BUT THE UPSTATE COULD SEE IFR
WITH THE RECENT PRECIP. A GRADUAL IMPROVEMENT IN FLIGHT CONDS AFT 15Z
THROUGH NOON...WITH VFR EXPECTED IN THE AFTERNOON ALL SITES. WINDS
WILL SHIFT AND REMAIN SW/LY AFT 14Z/15Z WITH LOW/MODERATE GUSTS
POSSIBLE BY MID/AFTERNOON.
OUTLOOK...A COLD FRONT WILL CROSS THE AREA THU NIGHT ALONG WITH
RESTRICTIONS DUE TO SHOWERS AND THUNDERSTORMS. SOME IMPROVING
CONDITIONS ARE LIKELY BEHIND THE FRONT ON FRIDAY BUT SCATTERED
SHOWERS WILL CONTINUE TO PRODUCE SOME RESTRICTIONS. HIGH PRESSURE
WILL BUILD OVER THE REGION BEGINNING FRIDAY NIGHT PRODUCING VFR
CONDITIONS.
CONFIDENCE TABLE...
02-08Z 08-14Z 14-20Z 20-00Z
KCLT MED 74% HIGH 85% MED 72% HIGH 100%
KGSP HIGH 81% HIGH 87% MED 62% HIGH 100%
KAVL MED 77% MED 78% HIGH 81% HIGH 100%
KHKY MED 76% HIGH 87% MED 68% HIGH 100%
KGMU MED 76% MED 75% MED 66% HIGH 100%
KAND MED 79% MED 76% MED 68% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MINIMUM TEMPERATURES FOR MARCH 28TH...
GSP 26 1982
CLT 25 1982
AVL 11 1887
RECORD MINIMUM TEMPERATURES FOR MARCH 29TH...
GSP 26 1899
CLT 26 2013
AVL 19 1982
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...LG/SBK
SHORT TERM...RWH
LONG TERM...JAT
AVIATION...SBK
CLIMATE...RWH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
311 PM CDT TUE MAR 24 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 307 PM CDT TUE MAR 24 2015
SYSTEM MOVING EAST ACROSS THE EASTERN PART OF THE AREA WILL
CONTINUE TO BRING THE GREATEST PRECIPITATION TO NORTHWEST IA
LATE THIS AFTERNOON INTO THE EVENING. THOUGH THERE HAS NOT BEEN MUCH
IN THE WAY OF SNOW SO FAR...WE HAVE BEEN GOING TO A LATE AFTERNOON
PEAK IN THE ACCUMULATION THREAT AND THE RAP SOUNDINGS ON BUFKIT HAVE
BEEN SHOWING A CONTINUED FIT WITH THAT IDEA. WITH SOME SPOTTY ICING
TO BOOT...WILL CONTINUE THE WINTER WEATHER ADVISORY FOR THE EASTERN
COUNTIES OF NORTHWEST IOWA. THE SPOTTY ICING IS LIKELY TO ABATE BUT
MAY SHOW UP AGAIN THIS EVENING WITH A VERY SLIGHT DROP IN
TEMPERATURES AND THE LOSS OF THE SOLAR RADIATION EFFECT THROUGH THE
CLOUDS. AS FOR THE SNOW...A COUPLE INCHES OF SLUSH WOULD COME
QUICKLY AND AT THE TIME PEOPLE ARE LIKELY TO BE OUT DRIVING...WHAT I
CALL THE PRAIRIE EARLY EVENING RUSH HOUR.
PRECIPITATION SHOULD END STEADILY FROM THE WEST LATE THIS AFTERNOON
AND THIS EVENING WHILE LOW CLOUDS WILL BE MORE STUBBORN...LASTING
THROUGH THE NIGHT FAR EAST/NORTHEAST. MEANWHILE...WEAK UPPER WAVE
SLIDING EAST SOUTHEAST TOWARD THE SOUTHERN EDGE OF THE AREA COULD
BRING SOME VERY SPOTTY LIGHT PRECIPITATION LATE TONIGHT INTO THE
START OF THE MORNING TO THE MISSOURI RIVER AREA...BUT POPS WILL BE
LOW AND THE DURATION OF ANY PRECIPITATION SHORT.
THE COLD FRONT ARRIVES LATE TONIGHT AND NORTHWEST WINDS QUICKLY
BECOME ESTABLISHED AT THE SURFACE. CONDITIONS SHOULD BECOME
WINDY BUT LOOKS LIKE WINDS WILL HOLD SHORT OF WIN ADVISORY LEVELS
EVEN THOUGH I AM GOING A LITTLE STRONGER THAN GUIDANCE IN THE MIXED
AIR.
SOME CLOUDS LIKELY IN THE COOL BUT MIXED AIR...BUT DO NOT EXPECT
THEM TO BE SOLID...AND CLOUDS SHOULD BE DECREASING IN THE
AFTERNOON.
AFTER LOWS NEAR OR JUST ABOVE 30 TONIGHT...MEANING LITTLE DROP INT
HE EAST...WEDNESDAY SHOULD BRING HIGHS MOSTLY IN THE 40S WITH A FEW
50 DEGREE READINGS SOUTH. THAT WILL OF COURSE BE WARMER FOR MOST OF
THE AREA BUT COOLER SOUTHWEST.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 307 PM CDT TUE MAR 24 2015
GENERALLY A RATHER TRANQUIL MEDIUM AND EXTENDED FORECAST WITH ONLY A
FEW TROUBLE SPOTS. SHARP NWLY WILL DEVELOP BY THURSDAY AND FRIDAY IN
THE WAKE OF TODAYS SYSTEM. THIS WILL SPELL A RETURN TO NEAR OR
SLIGHTLY BELOW NORMAL TEMPERATURES INTO THE END OF THE WEEK. WITH
MID-LVL RIDGING AMPLIFYING OVER THE WEST COAST...AND A PAIR OF
SHORTWAVES DROPPING DOWN THE WESTERN FLANK OF THE BROAD UPPER
TROUGH...A TIGHTENING LOW-LVL BAROCLINIC ZONE WILL DEVELOP ACROSS
THE DAKOTAS. THE FIRST SYSTEM WILL ZIP THROUGH THURSDAY...AND A
SECOND LATE FRIDAY. QPF WITH THESE SYSTEMS WILL BE LIGHT...BUT
COULD NOT RULE OUT THE OCCASIONAL RAIN/SNOW MIXTURE BOTH DAYS WITH
HIGHEST CHANCES FOR THE LOCAL AREA ON FRIDAY.
WE WILL SEE A GRADUAL WARMING TREND BEGIN THIS WEEKEND AND CONTINUE
INTO NEXT WEEK AS HEIGHTS BEGIN TO RISE OVER THE CENTRAL US. THE
WARMEST TEMPERATURES WILL BE FOCUSED EARLY NEXT WEEK WHERE WE COULD
MAKE A RUN INTO THE 70S ONCE AGAIN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1239 PM CDT TUE MAR 24 2015
MVFR TO IFR IN LOW CEILINGS...RAIN OR MIXED PRECIPITATION...AND
LIGHT FOG WILL ABATE TO VFR WEST OF THE JAMES RIVER THROUGH
25/00Z. EAST OF THE JAMES RIVER...PRECIPITATION AND LOWERED
VISIBILITIES SHOULD IMPROVE TO VFR VISIBILITIES FROM THE WEST
21Z-25/03Z...BUT CEILINGS 1-3K FEET ARE EXPECTED TO REMAIN. COLD
FRONT WILL BRING CEILINGS 2-4K FEET AFTER 25/12Z. SURFACE GUSTS TO
25 KNOTS MAY DEVELOP NORTHWEST OF BKX TO YKN AREA AFTER 25/15Z.&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...WINTER WEATHER ADVISORY UNTIL 1 AM CDT WEDNESDAY FOR IAZ002-003-
013-014-021-022-032.
&&
.FIRE WEATHER...
ISSUED AT 307 PM CDT TUE MAR 24 2015
A COLD FRONT WILL PASS THROUGH THE AREA WEDNESDAY
MORNING...BRINGING RATHER GUSTY WINDS ALONG WITH IT. TODAYS
WETTING RAINS HAVE MAINLY IMPACTED AREAS EAST OF THE JAMES
RIVER...LEAVING FUELS IN THE AREAS WEST OF THE RIVER DRY.
RELATIVE HUMIDITY VALUES WILL VALL INTO THE 25 TO 35 PERCENT RANGE
TOMORROW AFTERNOON...AND WILL LEAD TO HIGH TO VERY HIGH FIRE
DANGER RISKS IN THE AFTERNOON.
COOLER TEMPERATURES MOVE IN FOR THURSDAY AND FRIDAY...MINIMIZING
THE WILDFIRE RISK.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...WINTER WEATHER ADVISORY UNTIL 1 AM CDT WEDNESDAY FOR IAZ002-003-
013-014-021-022-032.
NE...NONE.
&&
$$
SHORT TERM...
LONG TERM...DUX
AVIATION...
FIRE WEATHER...DUX
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1225 AM CDT TUE MAR 24 2015
.UPDATE...
ISSUED AT 752 PM CDT MON MAR 23 2015
FOR NOW NOT PLANNING ANY MAJOR CHANGES TO THE FORECAST. BAND OF
WAA RAIN CURRENTLY MAKING ITS WAY INTO SOUTHWEST CWA. BASED ON
MODEL DATA AND LATEST SOUNDINGS ITS FAIR TO SAY I AM NOT SURE HOW
FAST/FAR THAT BAND WILL TRACK NORTHEAST. MAY NOT GET MUCH IN THE
WAY OF MEASURABLE PCPN IN THE NORTHEAST CWA UNTIL MORE ENERGY
COMES OUT ON TUESDAY. WILL CONTINUE TO WATCH THE ADVANCEMENT OF
RAIN THIS EVENING AND THEN DETERMINE ANY CHANGES THAT MIGHT NEED
TO BE MADE CONCERNING POPS..ETC. LOW TEMPERATURES LOOK MOSTLY ON
TARGET GIVEN OVERNIGHT CLOUDS AND LLJ.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 346 PM CDT MON MAR 23 2015
STRATUS DECK CONTINUES TO ERODE QUICKLY FROM SOUTHWEST TO
NORTHEAST ACROSS THE EASTERN CWA WITH TEMPS QUICKLY CLIMBING AS
THE SUN EMERGES. SNOWFALL FROM YESTERDAY WILL BE HISTORY FOR SOME
AREAS. ONCE AGAIN THE HRRR LOW-LEVEL CLOUD COVER PRODUCT PERFORMED
EXTREMELY WELL IN ERODING THE STRATUS DECK THIS AFTERNOON.
ATTENTION THEN TURNS TO THE STORM SYSTEM MOVING IN TONIGHT.
SHOWERS ARE ALREADY NOTED ACROSS SOUTHWEST SD AND APPROACHING THE
SOUTHWEST CWA. MODELS ARE COMING INTO BETTER AGREEMENT WITH A
DRIER SOLUTION OVER THE CWA. THAT SAID THOUGH...IT STILL APPEARS A
BAND OF WARM AIR ADVECTION RAINFALL WILL MOVE EASTWARD ACROSS THE
AREA LATE TONIGHT AND THROUGH THE DAY TUESDAY. ITS A QUESTION OF
JUST HOW FILLED IN AND INTENSE THIS BAND WILL BE. BACKED OFF ON
QPF A BIT THOUGH AS MODELS ARE RATHER LIGHT WITH ITS QPF OUTPUT.
OVERALL FORCING IS MODEST. COULD STILL BE DEALING WITH MIXED
PRECIP ACROSS THE EASTERN CWA LATE TONIGHT AND THROUGH THE DAY
TUESDAY. MODELS ALL SHOWING A DRY SLOT MOVING INTO THE WESTERN CWA
TUESDAY AFTERNOON...WITH BREEZY WEST TO NORTHWEST WINDS AND DRYING
CONDITIONS. RH VALUES WILL LIKELY FALL INTO THE 20S ACROSS THE
SOUTHWEST CWA ONCE AGAIN. TEMPS WILL WARM NICELY IN THE DRY
SLOT...ESPECIALLY OVER THE SOUTHWEST CWA AND MAY HAVE TO BUMP UP
HIGHS A FEW MORE DEGREES.
AS THE LOW PASSES TO THE EAST ON WEDNESDAY...STRONG NORTHWEST
WINDS DEVELOP. COULD BE CLOSE TO WIND ADVISORY LEVELS SO WILL HAVE
TO KEEP AN EYE ON THAT. WILL ALSO HAVE TO WATCH WRAP AROUND PRECIP
POTENTIAL ON THE BACK SIDE OF THE LOW. THERE ARE DISCREPANCIES IN
JUST HOW FAR SOUTH PRECIP WILL MAKE IT...WITH THE GFS THE FURTHEST
SOUTH THROUGH MUCH OF NORTHEAST SD AND WEST CENTRAL MN. THE EC
DOES NOT TAKE IT MUCH SOUTH OF THE ND/SD BORDER. GENERALLY WENT
WITH THE MORE RELIABLE EC AT THIS POINT. INTERESTING TO NOTE
THOUGH THAT THIS TIME AROUND THE GEM IS IN AGREEMENT WITH THE GFS.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 346 PM CDT MON MAR 23 2015
UPPER LEVEL PATTERN WILL TRANSITION FROM NORTHWEST FLOW TO A FLAT
RIDGE WITH SEVERAL WAVES PASSING THROUGH. THIS WILL RESULT IN
FLUCTUATING TEMPS THROUGH THE PERIOD. PATTERN DOES LOOK MOSTLY
DRY AS BEST UPPER ENERGY REMAINS NORTH OF THE STATE. TEMPS WILL
BE COOLEST ON THURSDAY...WITH A WARMING TREND INTO
SATURDAY...WHERE TEMPS WILL BE ABOVE NORMAL MOST LOCATIONS...ALONG
AND WEST OF THE MISSOURI RIVER. A STRONGER WAVE CRASHES THROUGH
THE RIDGE ON SATURDAY NIGHT BRINGING BREEZY CONDITIONS AND COOLER
TEMPS FOR SUNDAY...THEN A REBOUND OF TEMPS AGAIN FOR MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1223 AM CDT TUE MAR 24 2015
VFR CONDITIONS ARE EXPECTED THROUGH MUCH OF THE NIGHT AT ALL
TERMINALS. HOWEVER AN ADVANCING SYSTEM WILL BRING RAIN SHOWERS TO
THE REGION THROUGH TUESDAY. ACCOMPANYING THAT RAIN WILL BE LOWERED
CIGS...PROBABLY MOSTLY IN THE MVFR RANGE. LIGHT FOG WILL ALSO BE
POSSIBLE WITH THE LOWERED CIGS AND PCPN.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...TDK
SHORT TERM...TMT
LONG TERM...SCARLETT
AVIATION...WISE
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
923 PM CDT WED MAR 25 2015
.UPDATE...
UPDATED TO RAISE POPS FOR REMAINDER OF THIS EVENING FROM PORTIONS
OF NORTHEAST AR INTO THE MO BOOTHEEL AS WIDESPREAD SHOWERS AND
THUNDERSTORMS ARE PUSHING INTO THIS AREA.
JCL
UPDATE... /ISSUED 739 PM CDT WED MAR 25 2015/
UPDATED FOR SEVERE THUNDERSTORM WATCH THAT INCLUDES PORTIONS OF
NORTHEAST AR...THE MO BOOTHEEL...AND PORTIONS OF NORTHWEST TN
UNTIL 2 AM CDT THU. THE MAIN THREATS WILL BE DAMAGING WINDS AND
LARGE HAIL. UPDATED ZONE FORECASTS AND GRIDS ALREADY SENT. ALSO
UPDATED THE HAZARDOUS WEATHER OUTLOOK TO EXPAND THE SLIGHT RISK
OF SEVERE THUNDERSTORMS EASTWARD.
JCL
&&
.DISCUSSION... /ISSUED 328 PM CDT WED MAR 25 2015/
CURRENTLY...A 1007 MB LOW PRESSURE SYSTEM IS LOCATED OVER THE RED
RIVER VALLEY WITH A WARM FRONT EXTENDING EAST INTO THE NORTHERN
PART OF THE MIDSOUTH. DEWPOINTS HAVE RISEN INTO THE UPPER 50S AND
LOWER 60S JUST SOUTH OF THE BOUNDARY WITH SBCAPES OF 1000-1500
J/KG. TEMPS ARE IN THE 70S WITH VARIABLY CLOUDY SKIES ACROSS THE
FORECAST AREA. SOUTH WINDS ARE BLOWING AT 10 TO 15 MPH WITH SOME
HIGHER GUSTS.
THIS EVENING INTO TONIGHT...THE LATEST HRRR INDICATES THAT
ISOLATED STORMS MAY DEVELOP ALONG THE WARM FRONT OVER THE NEXT
COUPLE OF HOURS. THESE MAKES SENSE GIVEN THE LACK OF CAP ACROSS
THE AREA...DECENT HEATING AND MODERATE INSTABILITY. ANY STORMS
THAT DO FORM WILL LIFT NORTH OF THE AREA BY EARLY EVENING AND
SHOULD REMAIN SUB SEVERE. THE EARLY EVENING SHOULD BE QUIET AND
MILD. AS THE EVENING PROGRESSES LOW PRESSURE WILL TRACK INTO
NORTHERN ARKANSAS WITH THUNDERSTORMS PUSHING INTO AND DEVELOPING
ACROSS SOUTHERN MISSOURI AND NORTHERN ARKANSAS. BY LATE EVENING
EXPECT CONVECTIVE SEGMENTS TO REACH NORTHEAST ARKANSAS. AT THIS
POINT THE INSTABILITY WILL BE WEAKENING BUT THERE SHOULD BE A
SEVERE THREAT WINDOW OF A FEW HOURS ACROSS NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL AND EXTREME NORTHWEST TENNESSEE.
BY 03Z THERE IS STILL A FEW HUNDRED J/KG OF SBCAPE AND MODERATELY
STEEP LAPSE RATES SUFFICIENT WHEN COMBINED WITH THE SHEAR TO
SUPPORT THE CONTINUATION OF THE SEVERE THREAT UNTIL 06-07Z.
DAMAGING WINDS WILL BE THE MAIN THREAT WITH LARGE HAIL A SECONDARY
THREAT. AS THE COLD FRONT PUSHES IN SHOWER AND A THUNDERSTORM
CHANCES WILL INCREASE LATER TONIGHT ACROSS THE REST OF THE
MIDSOUTH. BY 12Z THU THE FRONT WILL BE LOCATED FROM PARIS TN TO
MEMPHIS TO THE ARKLATEX WITH MOST OF THE PRECIP POST FRONTAL BY
THAT POINT. TEMPS WILL BE DROPPING BEHIND THE FRONT ACROSS THE NW
HALF BRINGING AND ABRUPT END TO THE MILD WEATHER.
THURSDAY...COLD FRONT WILL PUSH THROUGH THE REMAINDER OF THE AREA
WITH SHOWERS AND A FEW THUNDERSTORMS MAINLY EAST OF THE
MISSISSIPPI RIVER. MANY PLACES WILL HAVE MORNING HIGHS WITH
FALLING OR STEADY TEMPS AS STRONG COLD AIR ADVECTION FOLLOWS THE
FRONT. THE SUN MAY PEEK OUT ACROSS NE AR BY LATE IN THE DAY AS THE
FRONT PUSHES EAST.
THURSDAY NIGHT THROUGH SATURDAY NIGHT...LARGE UPPER TROF OVER THE
EASTERN U.S. DURING THIS PERIOD WITH COOL NW FLOW ACROSS THE
MIDSOUTH. EXPECT WELL BELOW NORMAL TEMPERATURES...10 TO 15
DEGREES BELOW NORMAL...DURING THIS PERIOD. A COUPLE OF
DISTURBANCES MOVING THROUGH IN THE NW FLOW COULD PRODUCE PERIODS
OF LIGHT PRECIP BOTH FRIDAY AND SATURDAY. COULD EVEN BE A FEW SNOW
FLAKES ACROSS THE NORTHERN TIER SATURDAY MORNING THOUGH NOTHING
SIGNIFICANT EXPECTED AT THIS TIME. AS FAR AS THE POTENTIAL FOR
FREEZING TEMPS IS CONCERNED...LOOKS LIKE THE BEST CHANCES WILL BE
NORTH OF A JONESBORO AR TO SAVANNAH TN LINE SATURDAY MORNING AND
EAST OF A DYERSBURG TN TO FULTON MS LINE SUNDAY MORNING. SINCE WE
WILL NEED SOME CLEARING TO SEE SUBFREEZING TEMPS THESE
DISTURBANCES MOVING THROUGH THE FLOW MAKE FOR A DIFFICULT TEMP
FORECAST. STAY TUNED.
SUNDAY...LOOKING DRY AND MILDER AS THE UPPER TROF EXITS AND
SOUTHERLY WINDS DEVELOP. TEMPS BACK IN THE 60S.
SUNDAY NIGHT THROUGH WEDNESDAY...A COLD FRONT PROJECTED TO MOVE
THROUGH SUNDAY NIGHT WITH CHANCES FOR RAIN. THE MEDIUM RANGE
MODELS PUSH THE FRONT TO THE SOUTH WITH ONLY SMALL POPS EARLY
NEXT WEEK AND TEMPS BACK TO NORMAL. LOOKING MORE WET BY MIDWEEK AS
A MORE SIGNIFICANT SYSTEM MAY MOVE OUT OF THE MIDDLE OF THE
COUNTRY AND INTO THE MIDSOUTH.
SJM
&&
.AVIATION...
00Z TAF CYCLE
VFR THIS EVENING...WITH LOWER MVFR/IFR CLOUDS COMING IN BEFORE
DAWN. STORMS IN OK/AR WILL GRADUALLY WORK THEIR WAY TOWARDS
JBR...WHILE ADDITIONAL SHOWERS DEVELOP ACROSS THE REGION AFTER
MIDNIGHT. SOUTH WINDS WILL GRADUALLY SHIFT SOUTHWEST THRU WEST AND
THEN NORTHERLY AS TWO DISTINCT FRONTS PUSH THROUGH. RAIN...GUSTY
NORTH WINDS...AND SOME IFR CIGS EXPECTED BEHIND THE SECOND
BOUNDARY. VFR WEATHER ANTICIPATED LATE AT JBR...MKL AND MEM.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
739 PM CDT WED MAR 25 2015
.UPDATE...
UPDATED FOR SEVERE THUNDERSTORM WATCH THAT INCLUDES PORTIONS OF
NORTHEAST AR...THE MO BOOTHEEL...AND PORTIONS OF NORTHWEST TN
UNTIL 2 AM CDT THU. THE MAIN THREATS WILL BE DAMAGING WINDS AND
LARGE HAIL. UPDATED ZONE FORECASTS AND GRIDS ALREADY SENT. ALSO
UPDATED THE HAZARDOUS WEATHER OUTLOOK TO EXPAND THE SLIGHT RISK
OF SEVERE THUNDERSTORMS EASTWARD.
JCL
&&
.DISCUSSION... /ISSUED 328 PM CDT WED MAR 25 2015/
CURRENTLY...A 1007 MB LOW PRESSURE SYSTEM IS LOCATED OVER THE RED
RIVER VALLEY WITH A WARM FRONT EXTENDING EAST INTO THE NORTHERN
PART OF THE MIDSOUTH. DEWPOINTS HAVE RISEN INTO THE UPPER 50S AND
LOWER 60S JUST SOUTH OF THE BOUNDARY WITH SBCAPES OF 1000-1500
J/KG. TEMPS ARE IN THE 70S WITH VARIABLY CLOUDY SKIES ACROSS THE
FORECAST AREA. SOUTH WINDS ARE BLOWING AT 10 TO 15 MPH WITH SOME
HIGHER GUSTS.
THIS EVENING INTO TONIGHT...THE LATEST HRRR INDICATES THAT
ISOLATED STORMS MAY DEVELOP ALONG THE WARM FRONT OVER THE NEXT
COUPLE OF HOURS. THESE MAKES SENSE GIVEN THE LACK OF CAP ACROSS
THE AREA...DECENT HEATING AND MODERATE INSTABILITY. ANY STORMS
THAT DO FORM WILL LIFT NORTH OF THE AREA BY EARLY EVENING AND
SHOULD REMAIN SUB SEVERE. THE EARLY EVENING SHOULD BE QUIET AND
MILD. AS THE EVENING PROGRESSES LOW PRESSURE WILL TRACK INTO
NORTHERN ARKANSAS WITH THUNDERSTORMS PUSHING INTO AND DEVELOPING
ACROSS SOUTHERN MISSOURI AND NORTHERN ARKANSAS. BY LATE EVENING
EXPECT CONVECTIVE SEGMENTS TO REACH NORTHEAST ARKANSAS. AT THIS
POINT THE INSTABILITY WILL BE WEAKENING BUT THERE SHOULD BE A
SEVERE THREAT WINDOW OF A FEW HOURS ACROSS NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL AND EXTREME NORTHWEST TENNESSEE.
BY 03Z THERE IS STILL A FEW HUNDRED J/KG OF SBCAPE AND MODERATELY
STEEP LAPSE RATES SUFFICIENT WHEN COMBINED WITH THE SHEAR TO
SUPPORT THE CONTINUATION OF THE SEVERE THREAT UNTIL 06-07Z.
DAMAGING WINDS WILL BE THE MAIN THREAT WITH LARGE HAIL A SECONDARY
THREAT. AS THE COLD FRONT PUSHES IN SHOWER AND A THUNDERSTORM
CHANCES WILL INCREASE LATER TONIGHT ACROSS THE REST OF THE
MIDSOUTH. BY 12Z THU THE FRONT WILL BE LOCATED FROM PARIS TN TO
MEMPHIS TO THE ARKLATEX WITH MOST OF THE PRECIP POST FRONTAL BY
THAT POINT. TEMPS WILL BE DROPPING BEHIND THE FRONT ACROSS THE NW
HALF BRINGING AND ABRUPT END TO THE MILD WEATHER.
THURSDAY...COLD FRONT WILL PUSH THROUGH THE REMAINDER OF THE AREA
WITH SHOWERS AND A FEW THUNDERSTORMS MAINLY EAST OF THE
MISSISSIPPI RIVER. MANY PLACES WILL HAVE MORNING HIGHS WITH
FALLING OR STEADY TEMPS AS STRONG COLD AIR ADVECTION FOLLOWS THE
FRONT. THE SUN MAY PEEK OUT ACROSS NE AR BY LATE IN THE DAY AS THE
FRONT PUSHES EAST.
THURSDAY NIGHT THROUGH SATURDAY NIGHT...LARGE UPPER TROF OVER THE
EASTERN U.S. DURING THIS PERIOD WITH COOL NW FLOW ACROSS THE
MIDSOUTH. EXPECT WELL BELOW NORMAL TEMPERATURES...10 TO 15
DEGREES BELOW NORMAL...DURING THIS PERIOD. A COUPLE OF
DISTURBANCES MOVING THROUGH IN THE NW FLOW COULD PRODUCE PERIODS
OF LIGHT PRECIP BOTH FRIDAY AND SATURDAY. COULD EVEN BE A FEW SNOW
FLAKES ACROSS THE NORTHERN TIER SATURDAY MORNING THOUGH NOTHING
SIGNIFICANT EXPECTED AT THIS TIME. AS FAR AS THE POTENTIAL FOR
FREEZING TEMPS IS CONCERNED...LOOKS LIKE THE BEST CHANCES WILL BE
NORTH OF A JONESBORO AR TO SAVANNAH TN LINE SATURDAY MORNING AND
EAST OF A DYERSBURG TN TO FULTON MS LINE SUNDAY MORNING. SINCE WE
WILL NEED SOME CLEARING TO SEE SUBFREEZING TEMPS THESE
DISTURBANCES MOVING THROUGH THE FLOW MAKE FOR A DIFFICULT TEMP
FORECAST. STAY TUNED.
SUNDAY...LOOKING DRY AND MILDER AS THE UPPER TROF EXITS AND
SOUTHERLY WINDS DEVELOP. TEMPS BACK IN THE 60S.
SUNDAY NIGHT THROUGH WEDNESDAY...A COLD FRONT PROJECTED TO MOVE
THROUGH SUNDAY NIGHT WITH CHANCES FOR RAIN. THE MEDIUM RANGE
MODELS PUSH THE FRONT TO THE SOUTH WITH ONLY SMALL POPS EARLY
NEXT WEEK AND TEMPS BACK TO NORMAL. LOOKING MORE WET BY MIDWEEK AS
A MORE SIGNIFICANT SYSTEM MAY MOVE OUT OF THE MIDDLE OF THE
COUNTRY AND INTO THE MIDSOUTH.
SJM
&&
.AVIATION...
00Z TAF CYCLE
VFR THIS EVENING...WITH LOWER MVFR/IFR CLOUDS COMING IN BEFORE
DAWN. STORMS IN OK/AR WILL GRADUALLY WORK THEIR WAY TOWARDS
JBR...WHILE ADDITIONAL SHOWERS DEVELOP ACROSS THE REGION AFTER
MIDNIGHT. SOUTH WINDS WILL GRADUALLY SHIFT SOUTHWEST THRU WEST AND
THEN NORTHERLY AS TWO DISTINCT FRONTS PUSH THROUGH. RAIN...GUSTY
NORTH WINDS...AND SOME IFR CIGS EXPECTED BEHIND THE SECOND
BOUNDARY. VFR WEATHER ANTICIPATED LATE AT JBR...MKL AND MEM.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
619 PM CDT WED MAR 25 2015
.DISCUSSION...
UPDATED FOR 00Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 328 PM CDT WED MAR 25 2015/
DISCUSSION...
CURRENTLY...A 1007 MB LOW PRESSURE SYSTEM IS LOCATED OVER THE RED
RIVER VALLEY WITH A WARM FRONT EXTENDING EAST INTO THE NORTHERN
PART OF THE MIDSOUTH. DEWPOINTS HAVE RISEN INTO THE UPPER 50S AND
LOWER 60S JUST SOUTH OF THE BOUNDARY WITH SBCAPES OF 1000-1500
J/KG. TEMPS ARE IN THE 70S WITH VARIABLY CLOUDY SKIES ACROSS THE
FORECAST AREA. SOUTH WINDS ARE BLOWING AT 10 TO 15 MPH WITH SOME
HIGHER GUSTS.
THIS EVENING INTO TONIGHT...THE LATEST HRRR INDICATES THAT
ISOLATED STORMS MAY DEVELOP ALONG THE WARM FRONT OVER THE NEXT
COUPLE OF HOURS. THESE MAKES SENSE GIVEN THE LACK OF CAP ACROSS
THE AREA...DECENT HEATING AND MODERATE INSTABILITY. ANY STORMS
THAT DO FORM WILL LIFT NORTH OF THE AREA BY EARLY EVENING AND
SHOULD REMAIN SUB SEVERE. THE EARLY EVENING SHOULD BE QUIET AND
MILD. AS THE EVENING PROGRESSES LOW PRESSURE WILL TRACK INTO
NORTHERN ARKANSAS WITH THUNDERSTORMS PUSHING INTO AND DEVELOPING
ACROSS SOUTHERN MISSOURI AND NORTHERN ARKANSAS. BY LATE EVENING
EXPECT CONVECTIVE SEGMENTS TO REACH NORTHEAST ARKANSAS. AT THIS
POINT THE INSTABILITY WILL BE WEAKENING BUT THERE SHOULD BE A
SEVERE THREAT WINDOW OF A FEW HOURS ACROSS NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL AND EXTREME NORTHWEST TENNESSEE.
BY 03Z THERE IS STILL A FEW HUNDRED J/KG OF SBCAPE AND MODERATELY
STEEP LAPSE RATES SUFFICIENT WHEN COMBINED WITH THE SHEAR TO
SUPPORT THE CONTINUATION OF THE SEVERE THREAT UNTIL 06-07Z.
DAMAGING WINDS WILL BE THE MAIN THREAT WITH LARGE HAIL A SECONDARY
THREAT. AS THE COLD FRONT PUSHES IN SHOWER AND A THUNDERSTORM
CHANCES WILL INCREASE LATER TONIGHT ACROSS THE REST OF THE
MIDSOUTH. BY 12Z THU THE FRONT WILL BE LOCATED FROM PARIS TN TO
MEMPHIS TO THE ARKLATEX WITH MOST OF THE PRECIP POST FRONTAL BY
THAT POINT. TEMPS WILL BE DROPPING BEHIND THE FRONT ACROSS THE NW
HALF BRINGING AND ABRUPT END TO THE MILD WEATHER.
THURSDAY...COLD FRONT WILL PUSH THROUGH THE REMAINDER OF THE AREA
WITH SHOWERS AND A FEW THUNDERSTORMS MAINLY EAST OF THE
MISSISSIPPI RIVER. MANY PLACES WILL HAVE MORNING HIGHS WITH
FALLING OR STEADY TEMPS AS STRONG COLD AIR ADVECTION FOLLOWS THE
FRONT. THE SUN MAY PEEK OUT ACROSS NE AR BY LATE IN THE DAY AS THE
FRONT PUSHES EAST.
THURSDAY NIGHT THROUGH SATURDAY NIGHT...LARGE UPPER TROF OVER THE
EASTERN U.S. DURING THIS PERIOD WITH COOL NW FLOW ACROSS THE
MIDSOUTH. EXPECT WELL BELOW NORMAL TEMPERATURES...10 TO 15
DEGREES BELOW NORMAL...DURING THIS PERIOD. A COUPLE OF
DISTURBANCES MOVING THROUGH IN THE NW FLOW COULD PRODUCE PERIODS
OF LIGHT PRECIP BOTH FRIDAY AND SATURDAY. COULD EVEN BE A FEW SNOW
FLAKES ACROSS THE NORTHERN TIER SATURDAY MORNING THOUGH NOTHING
SIGNIFICANT EXPECTED AT THIS TIME. AS FAR AS THE POTENTIAL FOR
FREEZING TEMPS IS CONCERNED...LOOKS LIKE THE BEST CHANCES WILL BE
NORTH OF A JONESBORO AR TO SAVANNAH TN LINE SATURDAY MORNING AND
EAST OF A DYERSBURG TN TO FULTON MS LINE SUNDAY MORNING. SINCE WE
WILL NEED SOME CLEARING TO SEE SUBFREEZING TEMPS THESE
DISTURBANCES MOVING THROUGH THE FLOW MAKE FOR A DIFFICULT TEMP
FORECAST. STAY TUNED.
SUNDAY...LOOKING DRY AND MILDER AS THE UPPER TROF EXITS AND
SOUTHERLY WINDS DEVELOP. TEMPS BACK IN THE 60S.
SUNDAY NIGHT THROUGH WEDNESDAY...A COLD FRONT PROJECTED TO MOVE
THROUGH SUNDAY NIGHT WITH CHANCES FOR RAIN. THE MEDIUM RANGE
MODELS PUSH THE FRONT TO THE SOUTH WITH ONLY SMALL POPS EARLY
NEXT WEEK AND TEMPS BACK TO NORMAL. LOOKING MORE WET BY MIDWEEK AS
A MORE SIGNIFICANT SYSTEM MAY MOVE OUT OF THE MIDDLE OF THE
COUNTRY AND INTO THE MIDSOUTH.
SJM
&&
.AVIATION...00Z TAF CYCLE
VFR THIS EVENING...WITH LOWER MVFR/IFR CLOUDS COMING IN BEFORE
DAWN. STORMS IN OK/AR WILL GRADUALLY WORK THEIR WAY TOWARDS
JBR...WHILE ADDITIONAL SHOWERS DEVELOP ACROSS THE REGION AFTER
MIDNIGHT. SOUTH WINDS WILL GRADUALLY SHIFT SOUTHWEST THRU WEST AND
THEN NORTHERLY AS TWO DISTINCT FRONTS PUSH THROUGH. RAIN...GUSTY
NORTH WINDS...AND SOME IFR CIGS EXPECTED BEHIND THE SECOND
BOUNDARY. VFR WEATHER ANTICIPATED LATE AT JBR...MKL AND MEM.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND WEDNESDAY
ISSUED AT 212 PM CDT TUE MAR 24 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW CANADIAN
HIGH PRESSURE SHIFTING EAST OVER THE EASTERN GREAT LAKES EARLY THIS
AFTERNOON WHILE LOW PRESSURE IS MOVING ALONG THE KANSAS/OKLAHOMA
BORDER. AHEAD OF THE LOW...AN AREA OF MIXED PRECIPITATION WITH SOME
EMBEDDED THUNDERSTORMS IS OCCURRING OVER IOWA ON THE NOSE OF THE LLJ
AND REGION OF MOISTURE ADVECTION. THE SHORTWAVE AS THE PRIMARY
UPPER SUPPORT RESIDES OVER WESTERN KANSAS AND LOOKS RATHER
IMPRESSIVE EARLY THIS AFTERNOON. AS THE LOW HEADS NORTHEAST TOWARDS
SOUTHERN LAKE MICHIGAN TONIGHT...TIMING THE WINTRY PRECIP AND
POTENTIAL AMOUNTS ARE THE MAIN FORECAST CONCERNS.
TONIGHT...LEANED AWAY FROM THE NAM FOR THIS FORECAST...AS IT APPEARS
TO BE TOO FAR NORTH FROM THE CONSENSUS OF THE GFS/CANADIAN/AND
SREF. TAKING THE BLEND OF THE CONSENSUS...LOW PRESSURE WILL TRACK
FROM WESTERN MISSOURI TO SOUTHERN LAKE MICHIGAN TONIGHT. A BEEFY
LLJ UPWARDS OF 50KTS WILL SURGE NORTHEAST AHEAD OF THE LOW AND WILL
BE POINTED AT SOUTHERN WISCONSIN BY MIDNIGHT. THIS LLJ WILL
TRANSPORT PWATS BETWEEN 0.5 AND 0.75 INCHES ACROSS THE FORECAST AREA
(AS OPPOSED TO 0.15 PWAT CURRENTLY). WITH THE APPROACH OF THE LOW
AND SHORTWAVE...QG FORCING AND MID-LEVEL FGEN WILL STRENGTHEN TO SUPPORT
AN AREA OF PRECIP SPREADING NORTHEAST INTO CENTRAL WISCONSIN AND THE
SOUTHERN FOX VALLEY BETWEEN 03-06Z...AND THEN ACROSS THE REST OF THE
FORECAST AREA BY 10Z. THE STRONG LIFT AND AMPLE MOISTURE WILL LEAD
TO A RATHER INTENSE PERIOD OF PRECIP ONCE IT ARRIVES. TEMPERATURES
ALOFT REMAIN RATHER UNCERTAIN...BUT AM COUNTING ON THE INTENSE
PRECIP RATES AND LIFT TO COOL THE SLIGHTLY ABOVE FREEZING TEMPS
BETWEEN 850-800MB BACK TO OR BELOW FREEZING. AS A RESULT...AM
THINKING PRECIPITATION TYPES WILL BE MAINLY SNOW WITH SOME SLEET MIX
IN FROM WAUTOMA TO THE DOOR. AREAS AROUND
MANITOWOC/CALUMET/KEWAUNEE HAVE POTENTIAL TO SEE MIXED PRECIP THE
LONGEST...AND THIS WILL CUT INTO SNOW ACCUMULATIONS THERE SOME.
THOUGH SNOWFALL RATES COULD APPROACH AN INCH PER HOUR IN THE MORE
INTENSE SNOW BANDS...THE QUICK FORWARD MOTION OF THE SYSTEM WILL
ALSO LIMIT ACCUMS. WILL SHOW A WIDESPREAD 2 TO 4 INCHES...LOCALLY
HIGHER OVER THE FOX VALLEY WHERE WILL HAVE THE HIGHEST AMOUNTS.
THIS LOOKS LIKE A SOLID ADVISORY...PERHAPS TOWARDS A HIGHER END
ADVISORY OVER EASTERN WISCONSIN IF THERE IS LESS OF A MIX...AND
SNOWFALL RATES BECOME AN INCH PER HOUR. NORTH-CENTRAL WISCONSIN MAY
ONLY SEE 1-3 INCHES...BUT IT WILL BE SNOWING FOR THE MORNING
COMMUTE...THUS AN ADVISORY STILL LOOKS REASONABLE.
WEDNESDAY...SNOW WILL BE ONGOING ACROSS NORTH-CENTRAL AND FAR
NORTHEAST WISCONSIN WHERE AN ADDITIONAL INCH COULD FALL BY
MID-MORNING. ELSEWHERE...SNOW WILL BE DIMINISHING AS THE LOW TRACKS
TOWARDS NORTHERN LOWER MICHIGAN. REGARDLESS...THE MORNING COMMUTE
WILL LIKELY BE MESSY FOR MOST LOCATIONS. BEHIND THE SYSTEM...THE
REGION WILL BE UNDER THE INFLUENCE OF BROAD CYCLONIC FLOW. DRY
SLOTTING WILL MOVE OVER CENTRAL AND NORTHEAST WISCONSIN DURING THE
AFTERNOON...BUT THE SOUTHERN EXTENT OF THE COMMA HEAD WILL LINGER
OVER N-C WISCONSIN WHERE WILL LEAVE A CHANCE OF RAIN AND SNOW
THROUGH THE DAY. WEST WINDS WILL BECOME GUSTY DURING THE AFTERNOON
AS LOW LEVEL LAPSE RATES STEEPEN. GENERALLY REMAINING MOSTLY CLOUDY
WITH HIGHS RANGING FROM THE UPPER 30S TO MIDDLE 40S.
.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY
ISSUED AT 212 PM CDT TUE MAR 24 2015
COLD CYCLONIC FLOW ALOFT WILL DOMINATE THE WEATHER PATTERN INTO
THE WEEKEND...BRINGING BELOW NORMAL TEMPERATURES ALONG WITH CHANCES
OF RAIN AND SNOW AT SOME POINT WEDNESDAY NIGHT AND THURSDAY. PERSISTENT
NORTHERLY FLOW OFF LAKE SUPERIOR WILL BRING OCCASIONAL SNOW SHOWERS
TO FAR NORTHERN WISCONSIN WHERE SEVERAL INCHES ARE POSSIBLE ACROSS
THE SNOW BELT REGION OF VILAS COUNTY WITH LIGHTER AMOUNTS TO THE
SOUTH. UPPER TROUGH SWINGS ACROSS THE REGION THURSDAY...BRINGING A
CHANCE OF RAIN OR SNOW SHOWERS TO THE REMAINDER OF THE REGION.
THE BIG STORY BEHIND THIS TROUGH WILL BE THE COLD TEMPERATURES
ON FRIDAY. HIGH TEMPERATURES ON FRIDAY WILL ONLY BE IN THE MIDDLE 20S
TO LOWER 30S...OR SOME 10 TO 15 DEGREES BELOW NORMAL FOR THIS TIME OF
YEAR. VERY COLD TEMPERATURES ARE EXPECTED FRIDAY NIGHT WITH LOWS IN
THE SINGLE DIGITS AND TEENS.
SOME MODERATION IN TEMPERATURES IS EXPECTED ON SATURDAY. NEXT SYSTEM
TO AFFECT THE AREA SATURDAY NIGHT AND SUNDAY. SOME TIMING ISSUES NOTED
IF THIS SYSTEM WOULD OCCUR MORE SATURDAY NIGHT OR ON SUNDAY. THIS
COULD HAVE AN IMPACT ON PRECIPITATION TYPES IF IT SHOULD OCCUR MORE
ON SUNDAY. DRY CONDITIONS EXPECTED SUNDAY NIGHT INTO MONDAY NIGHT
AS HIGH PRESSURE MOVES ACROSS THE REGION. THERE IS A SMALL CHANCE
OF LIGHT RAIN ON TUESDAY...BUT CONFIDENCE IS LOW THAT THIS WOULD
OCCUR.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1222 PM CDT TUE MAR 24 2015
GOOD FLYING WEATHER THROUGH ABOUT THE MID-EVENING
HOURS...THEN CEILINGS AND VISIBILITIES WILL LOWER TO IFR OR LIFR
RANGE AFTER MIDNIGHT THROUGH EARLY TO MID-MORNING ON WEDNESDAY AS
LOW PRESSURE BRINGS WINTERY PRECIPITATION TO THE REGION. SNOW IS
EXPECTED NORTH AND WEST OF GREEN BAY WITH A MIX OF SNOW...SLEET AND
FREEZING RAIN CHANGING TO SNOW TO THE SOUTHEAST. ACCUMULATIONS OF 2
TO 4 INCHES WILL BE POSSIBLE FOR MOST LOCATIONS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 1 AM TO 10 AM CDT WEDNESDAY FOR
WIZ030-031-035>040-045-048>050.
WINTER WEATHER ADVISORY FROM 4 AM TO 1 PM CDT WEDNESDAY FOR
WIZ005-010>013-018>022-073-074.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1034 AM CDT TUE MAR 24 2015
.UPDATE...NO CHANGES PLANNED TO HEADLINES AT THIS TIME. HAVE BEEN
POURING OVER THE PROGGD SOUNDINGS FROM THE RAP AND NAM. SURE HOPE
THE RAP IS THE CORRECT SOLUTION AS THE NAM IS SHOWING A RATHER
SIGNIFICANT ICING EVENT WITH SURFACE TEMPS DROPPING BELOW FREEZING
DURING PEAK PRECIP INTENSITY WITH MAX WARM LAYER OVERHEAD. HOWEVER
KEYING ON THE RAP AT THIS TIME WITH A SLOWER COOLING IN THE
BOUNDARY LAYER. EXPECTING SUSTAINED SE WINDS AND THE INCREASE IN
CLOUD COVER TO NEGATE THE USUAL EVENING DROPOFF. WILL BE WATCHING
THESE TEMP TRENDS CAREFULLY AS THE AFTERNOON WEARS ON. THE 850
MILLIBAR WARM SURGE WILL RAMP UP LATER THIS AFTERNOON AND INTO THE
EVENING HOURS. AT THIS TIME FEEL THE CURRENT HEADLINE IN THE FAR
NORTH LOOKS GOOD. WILL ALSO KEEP AN EYE ON THE FAR WESTERN
COUNTIES FOR SLEET/SNOW ACCUM POTENTIAL AS THERMAL TROUGH/DYNAMIC
COOLING HAS A SAY AS THE EVENT WEARS ON.
PC
&&
.AVIATION/18Z TAFS/...VFR MOSTLY SKC THIS AFTERNOON. MAIN MOISTURE
SURGE ARRIVES TONIGHT WITH STRENGTHENING LLJ. PRECIP PROGGD TO
ARRIVE 23-02Z...SW-NE ACROSS THE CWA. FOR THE EASTERN TAF SITES
BULK OF PRECIP EXPECTED TO BE RAIN WITH SOME MIX POTENTIAL DUE TO
DYNAMIC COOLING LATER IN THE NIGHT. BEST SNOW ACCUMS EXPECTED TO
THE NORTH OF TAF SITES. WILL BE CAREFULLY MONITORING BOUNDARY
CONDITIONS FOR PRECIP TYPE. ALL IN ALL GOING FCST ON TRACK. IFR
CIGS/LIFR CIGS LIKELY AS THE MAIN PRECIP AREA MOVES THROUGH
OVERNIGHT. DECENT CONSENSUS FROM THE NAM/GFS MOS AND LLVL RH
PROGS. PRECIP WINDS DOWN QUICKLY WEDNESDAY MORNING AS WESTERLY
FLOW AND SUBSIDENCE TAKE HOLD IN THE WAKE OF THE TROUGH.
PC
&&
.PREV DISCUSSION... /ISSUED 240 PM CDT TUE MAR 24 2015/
TONIGHT AND WEDNESDAY - FORECAST CONFIDENCE...
UNSEASONABLE WARMTH ACROSS SRN WI WILL BE REPLACED BY MORE NORMAL
MID MARCH TEMPERATURES AS A COLD FRONT SWEEPS THROUGH THE AREA THIS
EVENING. SURFACE LOW TO TRACK THROUGH SRN WI AND DRAG THE COLD FRONT
BY IN ITS WAKE. FRONT MAY GET HUNG UP A BIT WITHIN BAGGIER REGIME OF
THIS SOMEWHAT ELONGATED LOW. HOWEVER RAP/NAM SOUNDINGS CONTINUE TO
SUPPORT A WINDY AND CHILLER REGIME FOR MUCH OF THE NIGHT AFTER THE
EARLY/MID EVENING FROPA. WINDS HIGHEST IN THE EASTERN CWA WHERE
FAVORABLE ONSHORE FETCH AND FRICTIONLESS FLOW MEETS THE LAKESHORE
COUNTIES. SO EXPECTING A FAIRLY RAPID TEMP DROPOFF TO ANY AREAS THAT
HAVE NOT COOLED FROM THE PREFRONTAL LAKE BREEZE DEVELOPMENT. SOME OF
THE EARLIER SOUNDINGS FOR LAKESHORE AREAS RAISED CONCERN FOR A
POSSIBLE WIND ADVISORY BUT THERE HAS BEEN SOME BACKING OFF OF THAT
SO WILL NOT GO THAT ROUTE AT THIS TIME. WILL ALSO KEEP ANY EVENING
POPS CONFINED TO THE NORTH AND NORTHEAST PORTION OF THE CWA CLOSER
TO INFLUENCE OF UPPER JET INDUCED FORCING AND EXTRAP OF COLDER TOPS
ON IR SAT ANIMATION.
TUESDAY - CONFIDENCE...MEDIUM
500 MILLIBAR NVA BUILDS IN WITH SUSTAINED NW FLOW. SURFACE/850 RIDGE AXIS
REMAINS TO OUR WEST WHICH ALLOWS FOR PLENTY OF MIXING TO SUSTAIN A COOL
NW BREEZE. 925 TEMPS WILL BE DOWN NEAR 0C SO BACK MUCH CLOSER TO NORMAL
CONDITIONS....ALTHOUGH THE SUSTAINED WIND WILL GIVE IT A BELOW NORMAL FEEL.
TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE HIGH
TRANSIENT SURFACE HIGH MIGRATES SOUTHEASTWARD FROM THE NORTHERN
GREAT PLAINS TUESDAY NIGHT...AND INTO THE WESTERN GREAT LAKES REGION
ON WEDNESDAY. WITH NVA ALOFT AND SUBSIDENT MOTION...EXPECT CLEAR
SKIES EARLY TUESDAY NIGHT. CLOUDS WILL INCREASE INTO WEDNESDAY AHEAD
OF A WEAK SHORTWAVE IMPULSE...AS IT EJECTS SOUTHEASTWARD FROM THE
PACIFIC NORTHWEST/NORTHERN ROCKIES INTO THE NORTHERN PLAINS STATES
BY WEDNESDAY AFTERNOON. DRY CONDITIONS WILL PREVAIL FOR THE
PERIOD...WITH HIGHS IN THE 40S ON WEDNESDAY.
WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE MEDIUM
LOW AMPLITUDE SHORTWAVE PROGRESSES EAST-SOUTHEASTWARD FROM THE
NORTHERN PLAINS WEDNESDAY NIGHT INTO THE LOWER GREAT LAKES REGION ON
FRIDAY. MODELS STILL SHOW A SWATH OF LIGHT PRECIPITATION ACROSS THE
AREA WEDNESDAY NIGHT...BUT FORCING IS LIMITED. KEPT LOW POPS FOR
THIS PERIOD WITH A RAIN-SNOW MIX POSSIBLE.
LONG TERM...THURSDAY NIGHT THROUGH MONDAY...FORECAST CONFIDENCE
MEDIUM
WEAK SHORTWAVE ENERGY WILL CONTINUE ACROSS THE REGION...WITH A
CLOSED UPPER LOW EVOLVING OVER THE NORTHERN GREAT LAKES REGION ON
FRIDAY...BEFORE SHIFTING EAST INTO NEW ENGLAND ON SUNDAY. SLIGHT
CHANCE POPS ARE WARRENTED CWA-WIDE FOR THE THURSDAY NIGHT/FRIDAY
PERIOD AND AGAIN IN THE NE CWA ON FRIDAY NIGHT AND SATURDAY.
AVIATION/00Z TAFS/...SURFACE LOW VCNTY CNTRL WI CONTINUES TO SHIFT
EAST PER 3HR PRES FALLS. WARM ADVECTION REGIME AHEAD OF THE LOW
GENERATING PLENTY OF MID/HIGH LEVEL CLOUDINESS. THE LOW IS EXPECTED
TO TRACK TOWARDS NE IL/SE WI/SW LWR MI VCNTY BY 00Z. THIS WILL BRING
THE COLD FRONT SOUTH THIS EVENING WITH DECENT PUSH OF NNE WINDS
ASSOCIATED WITH POST FRONTAL PRESSURE RISES. STILL LOOKING AT A 01-02Z
WIND SHIFT AT KMKE TO A MORE NORTH/NORTHEAST DIRECTION. POST FRONTAL
EVENING STRATUS POTENTIAL LOOKS TRANSIENT AS DRYING NOTED AFTER 6Z.
PROGS SHOW DRY CONDITIONS AS HIGH PRESSURE WORKS INTO IA/MN REGION LATER
IN THE DAY. HOWEVER STILL A NW BREEZE TUESDAY WITH LINGERING PRESSURE
GRADIENT THOUGH NOT AS GUSTY.
MARINE...UPGRADED GALE WATCH TO GALE WARNING AND STAGGERED START
TIMES A BIT IN A NORTH/SOUTH FASHION TO ACCOUNT FOR THE SOUTHWARD
PROPAGATION OF GALE FORCE WINDS. UPSTREAM POST FRONTAL PRESSURE RISES
ACROSS MN SUPPORT THIS GALE EVENT WITH FAVORABLE NNE FETCH LEADING
TO A SIZABLE BUILDUP IN THE WAVE ACTION.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 1 AM TO 10 AM CDT WEDNESDAY FOR
WIZ046-047-051-052.
LM...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 PM CDT
WEDNESDAY FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
WEDNESDAY THROUGH MONDAY...WOOD
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
1245 AM CDT THU MAR 26 2015
.DISCUSSION...
UPDATED FOR THE 06Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
A COLD FRONT AND ASSOCIATED LINE OF SHOWERS AND THUNDERSTORMS
STRETCHED FROM MENA TO BATESVILLE AS OF 05Z...BUT WILL MOVE
THROUGH THE REMAINDER OF ARKANSAS OVER THE NEXT 8 HRS OR SO.
EXPECT -TSRA TO AFFECT CENTRAL AND SOUTHERN SITES STARTING AROUND
07Z FOR KHOT AND KADF...AND MORE TOWARDS 08Z-09Z AT KPBF AND KLLQ.
HAVE TEMPO GROUPS FOR THUNDER AND CORRESPONDING LOW CIGS/VSBY TO
ACCOUNT FOR THIS...WITH PREVAILING -SHRA LASTING THROUGH MID
MORNING OR SO BEFORE RAINFALL FINALLY PUSHES EAST OF THE AREA.
BEHIND THE FRONT CIGS WILL DROP TO IFR LEVELS UP NORTH AND LIKELY
TO 2500 FT AGL OR LOWER ACROSS CENTRAL AND SOUTHERN ARKANSAS.
ADDITIONALLY...STRONG POST-FRONTAL NORTHERLY WINDS WILL AFFECT
ALL SITES. HAVE NORTHERLY GUSTS TO AT LEAST 20KT AT ALL SITES BUT
EXPECT GUSTS TO 25-30KT WILL BE POSSIBLE AROUND KLIT AFTER
DAYBREAK.
A RETURN TO VFR CONDITIONS IS EXPECTED BY LATE AFTERNOON AT ALL
SITES.
&&
.PREV DISCUSSION... /ISSUED 251 PM CDT WED MAR 25 2015/
SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
A FEW STRONG THUNDERSTORMS DEVELOPED OUTSIDE OF THE CWA IN NORTHEAST
TEXAS AND SW ARKANSAS DURING THE MID TO LATE MORNING HOURS ALONG AN
AXIS OF HIGHER DEWPOINTS. THROUGH THE DAY TODAY...A NEARLY
STATIONARY WARM FRONT REMAINS DRAPED ACROSS ARKANSAS FROM FORT SMITH
TO MOUNTAIN HOME. THIS FRONT WILL CONTINUE TO WOBBLE THROUGH THE DAY
BEFORE LIFTING MORE TO THE NORTH BY LATER THIS AFTERNOON AND
EVENING.
SURFACE LOW WILL CONTINUE TO PUSH TO THE NORTHEAST...AT THIS
POINT...DID SLOW DOWN THE TIMING OF THE MAIN LINE OF PRECIP. LATEST
RUNS OF HRRR HAS A FEW STRONGER STORMS DEVELOPING ACROSS OKLAHOMA
AND FOLLOWING CLOSE TO WHERE THE STATIONARY FRONT IS CURRENTLY
LOCATED. THE LARGEST THREAT WITH THESE INITIAL STORMS WILL BE LARGE
HAIL...WITH DAMAGING WINDS...AND PERHAPS EVEN A TORNADO POSSIBLE.
THE TORNADO THREAT IS FAIRLY LOW WITH THESE STORMS...WITH FAIRLY
HIGH LCL VALUES. SOME OF THE HIRES MODELS DO SUGGEST THESE MAY FALL
A BIT...BUT NOT UNTIL LATER IN THE EVENING.
CONTINUE TO EXPECT A LINE OF THUNDERSTORMS TO DEVELOP...GENERALLY
ALONG AND BEHIND THE MAIN FRONT AND MOVE THROUGH THE STATE AFTER
00Z...WITH THUNDERSTORMS SWEEPING THROUGH THE STATE. LARGE HAIL AND
DAMAGING WINDS WILL AGAIN BE POSSIBLE...BUT TORNADOES WILL BE
LIMITED AS THE COLD FRONT QUICKLY OUTRACES THE STORMS. CONTINUES TO
LOOK THAT THE HEAVIEST OF THE PRECIPITATION WILL BE LIMITED NW OF
THE CWA.
LATER IN THE SHORT TERM...LARGE UPPER TROUGH WILL MOVE ACROSS THE
AREA...AND WITH UPPER ENERGY RIDING AROUND THE TROUGH...SOME SMALL
CHANCES WILL EXIST FOR WINTRY PRECIPITATION. BUT WITH TEMPERATURES
CONTINUING TO COME BACK A BIT WARMER...THE CHANCES CONTINUE TO
LESSEN. NO ACCUMULATIONS OR WINTER WX HAZARDS ARE EXPECTED.
LONG TERM...SUNDAY THROUGH WEDNESDAY
NEAR...TO SLIGHTLY ABOVE NORMAL TEMPERATURES ARE EXPECTED DURING
THIS PERIOD. PRECIPITATION FORECASTS WILL REFLECT LOWER FORECAST
CONFIDENCE WITH REGARD TO FEATURES IN EXPECTED SPLIT FLOW ACROSS
THE U.S.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 56 36 54 35 / 40 20 20 20
CAMDEN AR 61 42 62 42 / 50 10 10 10
HARRISON AR 55 34 53 33 / 30 20 20 20
HOT SPRINGS AR 61 39 60 40 / 30 10 10 10
LITTLE ROCK AR 60 39 57 39 / 40 10 20 20
MONTICELLO AR 61 37 60 40 / 70 10 10 10
MOUNT IDA AR 62 35 61 37 / 30 10 10 10
MOUNTAIN HOME AR 57 35 54 34 / 30 20 20 20
NEWPORT AR 57 34 54 35 / 60 10 20 20
PINE BLUFF AR 58 40 56 38 / 60 10 10 10
RUSSELLVILLE AR 60 37 58 38 / 30 10 20 20
SEARCY AR 57 36 56 35 / 50 10 20 20
STUTTGART AR 57 39 55 37 / 60 10 20 20
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...64
AREA FORECAST DISCUSSION
NWS JACKSON KY
357 AM EDT THU MAR 26 2015
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 357 AM EDT THU MAR 26 2015
A SURFACE COLD FRONT IS CURRENTLY ALIGNED FROM NORTHEAST OHIO
DOWN THROUGH NORTH CENTRAL AND SOUTHWESTERN KENTUCKY. CONVECTION
HAS BEEN ONGOING OFF TO OUR WEST...AND HAS BEEN SHOWING A GENERAL
WEAKENING TREND ACCORDING TO THE LIGHTNING DATA AND WARMING CLOUD
TOPS EVIDENT ON THE IR SATELLITE. THERE HAS BEEN SOME NEW
DEVELOPMENT OUT AHEAD OF THE MAIN CLUSTERS...WITH SOME SCATTERED
STORMS POPPING UP JUST EAST OF I-75 IN NORTH CENTRAL KENTUCKY.
EASTERN KENTUCKY REMAINS IN THE WARM SECTOR...ALTHOUGH A FEW
SHELTERED VALLEYS IN OUR FAR EAST HAVE MANAGED TO DROP OFF INTO
THE 40S.
THE MODELS HAVE REMAINED IN PRETTY GOOD AGREEMENT WITH THE
DEVELOPING DEEP LONG WAVE TROUGH TO MOVE EAST ACROSS THE
MISSISSIPPI VALLEY. INITIALLY...HAVE FOLLOWED THE HRRR THROUGH
THIS MORNING...AND THEN A BLEND OF THE MODELS THEREAFTER.
CONVECTION WILL DRAW CLOSER TO THE AREA THROUGH DAWN...WITH AT
LEAST SOME SCATTERED ACTIVITY TO CONTEND WITH THROUGH THE MORNING
HOURS...PARTICULARLY IN THE WESTERN HALF OF THE CWA. THE MAIN
BATCH OF CONVECTION SHOULD STAY TO THE NORTHWEST. A STRENGTHENING
UPPER LEVEL JET ACROSS THE OHIO VALLEY WILL HELP RECHARGE THE
FRONT THIS AFTERNOON...SO WIDESPREAD PRECIPITATION WILL EVENTUALLY
MOVE IN ACROSS ALL OF EASTERN KENTUCKY THROUGH EARLY THIS EVENING.
SHOWERS AND SCATTERED THUNDERSTORMS WILL GIVE WAY TO MAINLY RAIN
BEHIND THE DEPARTING COLD FRONT...WITH THE SOUTHEAST LIKELY SEEING
THE HIGHER AMOUNTS OF QPF...WHERE A HALF INCH OR MORE COULD FALL.
DRY SLOTTING WILL WORK IN TONIGHT BEHIND AN INITIAL DEPARTING
SHORT WAVE TROUGH...WITH MOISTURE LIKELY CUTTING OFF BEFORE
TEMPERATURES GET COLD ENOUGH TO SUPPORT A FEW FLAKES. ON
FRIDAY...THE MAIN TROUGH AXIS WILL MOVE THROUGH THE AREA DURING
THE AFTERNOON HOURS...ALLOWING FOR SOME ISOLATED TO SCATTERED
SHOWERS.
HIGHS TODAY WILL LIKELY BE ESTABLISHED IN THE MORNING FOR MOST
LOCATIONS. READINGS WILL RANGE FROM AROUND 60 IN THE FAR
NORTHWEST...TO THE LOW TO MID 70S IN FAR EAST AND SOUTHEAST.
TEMPERATURES WILL FALL OFF TO THE 40S AND 50S BY LATE IN THE
DAY...WITH LOWS TONIGHT BOTTOMING OUT IN THE LOW TO MID 30S. HIGHS
ON FRIDAY WILL ONLY RECOVER TO THE 40S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 357 PM EDT WED MAR 25 2015
GUIDANCE IS IN GOOD AGREEMENT WITH THE BASE OF THE AMPLIFIED
TROUGH AXIS MOVING ACROSS THE OHIO VALLEY TO BEGIN THE PERIOD.
UNDER NORTHWEST FLOW AND COLDER AIR ALOFT MOVING ACROSS BASED ON
FORECAST SOUNDINGS...IT SEEMS REASONABLE TO MAINTAIN SMALL CHANCES
OF RAIN SHOWERS FRIDAY EVENING. AS WE COOL OFF...WOULD EXPECT A
CHANGE OVER TO A MIX/SNOW SHOWERS FRIDAY NIGHT PARTICULARLY
ACROSS THE FAR SE. BASED ON FORECAST SOUNDINGS WE REALLY DRY OUT
IN THE UPPER LEVELS BY SATURDAY MORNING...BUT SOUNDINGS TRY TO AT
LEAST HOLD ON TO SOME HIGH LEVEL CLOUDS. GIVEN THE COLD AIR MASS
IN PLACE WITH H850 SUB MINUS 10 IT WILL BE A COLD NIGHT WITH LOWS
IN THE LOW TO MID 20S. THIS UPPER LEVEL TROUGH CONTINUES TO SLIDE
EAST SATURDAY WITH THE COLD AIR MASS KEEPING HIGHS IN THE UPPER
30 TO LOWER 40S MOST SPOTS.
THE CANADIAN HIGH WILL CONTINUE TO BUILD SOUTHEAST SATURDAY INTO
SATURDAY NIGHT. THIS WILL BE THE BEST NIGHT FOR CLEAR SKIES AND
FROST. RIGHT NOW IT ALL DEPENDS ON HOW THE HIGH ALIGNS ACROSS THE
REGION TO WHERE THE MAX POTENTIAL FOR COOLING WILL BE. THE HIGH
SLIDES EAST FOR SUNDAY USHERING IN RETURN FLOW AND WARMER TEMPS.
WHILE UNCERTAINTY REMAINS ON THE EXACT EVOLUTION OF THE SYSTEM
MOVING INTO THE BEGINNING OF NEXT WEEK WITH A MORE PROGRESSIVE
GFS VERSUS OTHER GUIDANCE...EITHER WAY IT DOES LOOK LIKE CHANCES
OF RAIN SHOWERS INCREASE SUNDAY NIGHT INTO MONDAY. THERE IS ANOTHER
POTENTIAL SYSTEM BY MID WEEK WITH MODEL UNCERTAINTY REMAINING
HERE. THE GFS IS AGAIN QUICKER...WITH MORE OF A SOUTHERN STREAM
INFLUENCE VERSUS THE ECMWF NORTHERN STREAM FRONT BEING THE BIGGER
INFLUENCE. GIVEN THE UNCERTAINTY IN THESE SYSTEMS...DID STICK
CLOSE TO A MODEL BLEND...WHICH KEEPS SLIGHT TO CHANCE POPS WITH
BOTH SYSTEMS. OTHERWISE THE BEST BREAK IN THE ACTIVE PATTERN
LOOKS TO BE ON TUESDAY IN BETWEEN THESE SYSTEMS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 154 AM EDT THU MAR 26 2015
VFR CONDITIONS WILL BE MAINTAINED THROUGH 12Z...WITH JUST SOME CU
AT AROUND 5K FEET AGL FROM TIME TO TIME. CONVECTION WILL THEN
THREATEN FROM THE WEST BETWEEN 12 AND 16Z...WITH
CEILINGS/VISIBILITIES DROPPING DOWN TO MVFR. AS A COLD FRONT
SHIFTS SOUTHEAST ACROSS THE AREA THIS AFTERNOON...WIDESPREAD
PRECIPITATION AND CEILINGS LOWERING TO IFR ARE EXPECTED. LIGHT
WINDS OVERNIGHT WILL PICK UP TOWARDS DAWN AND ESPECIALLY BY MID-
MORNING. SOUTHWEST WINDS OF AROUND 10 KTS...WITH GUSTS RANGING
FROM 15 TO 20 KTS...WILL SHIFT TO THE NORTHWEST AS THE FRONT
PASSES BY TO THE SOUTHEAST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GEOGERIAN
LONG TERM...DJ
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS BILLINGS MT
310 AM MDT THU MAR 26 2015
.SHORT TERM...VALID FOR TDY AND FRI...
STRONG UPPER LEVEL RIDGE EXISTS ALONG THE WEST COAST BUT IT IS
DIRTY...WITH AN ABUNDANCE OF PACIFIC MOISTURE SPILLING OVER THE
RIDGE IN THE NW FLOW OVER OUR REGION. WEAK ENERGY DROPPING INTO
THE NORTHERN PLAINS WITH A 140KT H3 JET OVER EASTERN MT IS
PRODUCING SOME LIGHT PCPN NEAR THE DAKOTAS BORDER...WHICH WILL
SHIFT EAST OF OUR CWA OVER THE COMING HOURS. NW FLOW IS ALSO
GENERATING SOME LIGHT SHOWERS OR SPRINKLES IN UPSLOPE AREAS S/SE
OF BILLINGS AND OVER THE MTNS. LOOKING UPSTREAM...AREAS OF LIGHT
PCPN IMPACT WESTERN MT AS WELL. OVERALL WE SHOULD SEE CLOUDY SKIES
PERSIST TODAY DESPITE THE SLOWLY BUILDING HEIGHTS WITH AREAS OF
LIGHT SHOWERS OR SPRINKLES...MAINLY OVER THE MTNS AND IN UPSLOPE
REGIONS BUT THERE MAY BE ENOUGH DIURNAL INSTABILITY WITH STEEP MID
LEVEL LAPSE RATES TO PRODUCE SOME SPRINKLES ELSEWHERE INCLUDING
BILLINGS...AS RECENT HRRR RUNS SUGGEST. ANOTHER PIECE OF ENERGY
WILL DROP INTO THE NORTHERN PLAINS TONIGHT AND THIS SHOULD ENHANCE
PCPN AGAIN NEAR THE DAKOTAS BORDER...IE NEAR AND EAST OF SFC TROF.
OTHERWISE WE WILL SEE DRYING FROM WEST TO EAST LATE TONIGHT INTO
FRIDAY AS THE RIDGE CONTINUES TO PUSH EAST INTO THE NORTHERN
ROCKIES. DOWNSLOPE GRADIENTS WILL PERSIST FOR GUSTY WINDS ALONG
OUR FOOTHILLS OVER THE NEXT TWO DAYS. DO NOT EXPECT ANY HIGHLIGHTS
BUT BIG TIMBER HAS BEEN GUSTING INTO THE 40S ALREADY. HAVE RAISED
WIND SPEEDS SOME FROM BIG TIMBER TO 3HT AS THESE AREAS ARE FAVORED
IN A NW FLOW CHINOOK. TEMPS WILL RISE INTO THE LOWER TO MID 60S
TODAY IN WEST AND CENTRAL PARTS...AND INTO THE LOWER 70S FRIDAY.
HIGHS WILL APPROACH RECORDS AT LIVINGSTON AND BILLINGS ON FRIDAY.
THINGS GET MORE INTERESTING SATURDAY AS THE UPPER RIDGE BREAKS
DOWN WITH THE PASSAGE OF A PACIFIC SHORTWAVE AND COLD FRONT.
MODELS CONTINUE TO DISAGREE IN THE AMOUNT OF SPLITTING THAT THIS
ENERGY WILL UNDERGO IN THE EASTERN PACIFIC BEFORE IT MOVES INLAND.
LATEST ECMWF AND CANADIAN HAVE TRENDED SLOWER AND STRONGER WITH
THE WAVE...WHEREAS THE GFS IS CONTINUING WITH A WEAKER NORTHERN
SPLIT AND IS THUS FASTER. GIVEN THIS FEATURE IS IN A DATA VOID
AREA OVER THE PACIFIC AM NOT SURE WHICH SCENARIO IS PREFERRED SO
WILL STAY WITH A COMPROMISE AT THIS TIME. OVERALL EXPECT A FRONTAL
PASSAGE BY AFTERNOON WITH INCREASED SHOWER ACTIVITY ALONG AND
BEHIND THE FRONT. A SLOWER TIMING OF THIS FRONT WOULD YIELD WARMER
PREFRONTAL CONDITIONS AND THE POSSIBILITY OF A FEW TSTMS...AS THE
NAM AND ECMWF SHOW LIFTED INDICES NEAR ZERO. MAIN ISSUES ON
SATURDAY WILL REVOLVE AROUND FIRE WEATHER AND WIND AND WILL
CONTINUE TO HIGHLIGHT POTENTIAL FOR HIGH TEMPS...LOW RHS...STRONG
WINDS AND A FRONTAL PASSAGE IN THE FIRE WEATHER FORECAST. ALL
MODELS SHOWING NEAR 50 KTS OF MID LEVEL WIND WITH THIS SYSTEM SO
AN AFTERNOON ONSET OF SUBSIDENCE COULD PRODUCE VERY STRONG WINDS
ESPECIALLY FOR OUR WESTERN PARTS. STRONG W-NW WINDS SHOULD PUSH
ACROSS OUR PLAINS BY SATURDAY NIGHT. AGAIN...STRESS THE TIMING
UNCERTAINTY HERE.
ANYONE PLANNING OUTDOOR ACTIVITIES ON SATURDAY SHOULD BE AWARE OF
THE POTENTIAL FOR STRONG WINDS AND MONITOR THE FORECAST.
JKL
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MEDIUM RANGE GUIDANCE IN OVERALL GOOD AGREEMENT INTO THE EXTENDED.
UPPER HEIGHTS BUILD ACROSS THE NORTHERN ROCKIES FOR SUNDAY INTO
MONDAY BEHIND SATURDAYS SYSTEM FOR DRY CONDITIONS. NEXT VIGOROUS
SYSTEM TO BREAK DOWN THE RIDGE ON TUESDAY. THIS SYSTEM NOT LOOKING
LIKE A BIG PRECIP MAKER WITH DOWNSLOPE FLOW...BUT COULD BE
ANOTHER WIND PRODUCER. BEHIND THE TUESDAY SYSTEM...AN OVERALL
PRGRESSIVE FLOW PATTERN DEVELOPS WITH MUCH LESS AMPLIFICATION.
THIS WILL PUSH SEVERAL IMPULSES THROUGH THE FLOW AND KEEP A FEW
SHOWERS IN THE FORECAST INTO NEXT THURSDAY. HIGH TEMPERATURES WILL
COOL TO MORE SEASONAL LEVELS INTO THE 50S. FRIEDERS
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL INTO TONIGHT. THERE WILL BE A FEW
SHOWERS IN AND NEAR THE MOUNTAINS FOR LOCAL MOUNTAIN OBSCURATIONS.
OTHERWISE...MAINLY MID LEVEL CLOUDINESS EXPECTED. FRIEDERS
&&
.PRELIMINARY POINT TEMP/POPS...
TDY FRI SAT SUN MON TUE WED
-------------------------------------------------------
BIL 064 045/073 048/073 040/065 041/070 045/065 038/058
1/E 00/B 03/W 20/B 00/U 03/W 22/W
LVM 064 044/073 047/067 037/065 040/068 042/058 031/055
1/N 00/N 03/W 21/B 00/U 14/W 22/W
HDN 064 038/075 042/076 035/066 035/072 039/068 036/059
1/E 00/B 03/W 20/B 00/U 03/W 22/W
MLS 058 041/071 044/074 035/063 037/069 038/067 037/057
1/E 10/B 03/W 20/B 00/U 02/W 22/W
4BQ 058 039/071 040/077 036/064 036/070 039/069 035/058
2/W 20/B 03/W 30/B 00/U 01/B 21/N
BHK 050 035/065 039/073 035/061 033/066 037/066 035/054
2/W 30/E 02/W 30/U 00/U 02/W 31/N
SHR 059 038/070 039/077 035/065 035/070 038/069 034/055
2/W 10/B 03/W 31/B 00/B 02/W 32/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
144 AM EDT THU MAR 26 2015
.SYNOPSIS...
A WAVE OF LOW PRESSURE WILL BRING A ROUND OF PRECIPITATION
TODAY WHICH WILL START AS RAIN BUT MIX WITH WET SNOW AS COOLER
AIR BUILDS IN BEHIND THE SYSTEM. WINTER-LIKE WEATHER WILL RETURN FRIDAY
WITH BELOW NORMAL TEMPERATURES AND SOME SNOW SHOWERS.
&&
.NEAR TERM /THROUGH TODAY/...
THE MAINLY DRY WEATHER SHOULD CONTINUE OVERNIGHT WITH THE MAIN
FORECAST CHALLENGE HOW MUCH CLOUD COVER THERE WILL BE. DESPITE THE
DRIER AIR ALOFT...THE 00Z BUF SOUNDING SHOWS MOISTURE BENEATH 2K FT
WHICH IS PROBABLY BEING ENHANCED BY THE MOIST AIR MOVING ACROSS THE
ICE ON LAKE ERIE. THIS MAY RESULT IN A LOW STRATUS DECK IN SPOTS AS
DEPICTED BY THE HRRR AND NAM BUFKIT. OTHERWISE...EXPECT SOME
LINGERING MID AND HIGH CLOUDS WITH THE DEPARTING SYSTEM. IF SKIES
CLEAR LONG ENOUGH...SOME PATCHY FOG IS POSSIBLE.
OTHERWISE...TEMPERATURES SHOULD VERY SLOWLY DROP INTO THE MID TO
UPPER 30S LATE TONIGHT.
18-21Z NAM/GFS/SREF GUIDANCE HAS CONTINUED THE COOLING
TREND...WHICH INCREASES THE LIKELIHOOD THAT PRECIPITATION WILL MIX
WITH SNOW ON THURSDAY. PRECIPITATION WILL PROBABLY START AS
RAIN WITH A CONSENSUS QPF OF ABOUT A HALF INCH. TEMPERATURES WILL
COOL AS A COLD FRONT GRADUALLY SLIDES EAST OF THE REGION DURING
THE DAY WHEN LOW PRESSURE TRACKS ALONG THE FRONT AND PASSES SOUTH
OF THE REGION DURING THE DAY. SNOW WILL MIX IN FIRST IN NORTHERN
AND WESTERN PORTIONS OF THE CWA...INCLUDING THE NIAGARA
FRONTIER...EASTERN LAKE ONTARIO REGION...AND FAR WESTERN PORTIONS
OF THE SOUTHERN TIER. ACCUMULATION SHOULD BE LIGHT DUE TO THE
NEAR OR SLIGHTLY ABOVE FREEZING TEMPERATURES...BUT A WET INCH OR
TWO IS POSSIBLE IN STEADIER SNOWS MAINLY ON GRASSY SURFACES OR
ACROSS HIGHER TERRAIN.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
WHILE THE CONCERN DURING THE DAYS LEADING UP TO THIS PERIOD HAS BEEN
FOR ENOUGH RAIN TO CAUSE SOME FLOODING...THERE IS NOW A SUGGESTION
BY THE VARIOUS GUIDANCE PACKAGES THAT ENOUGH COLD AIR COULD MAKE IT
FAR ENOUGH SOUTH OF LAKE ONTARIO TO SUPPORT SOME ACCUMULATING SNOW.
THE STEADIEST AND HEAVIEST PCPN WILL HAVE MOVED OFF TO OUR EAST BY
THE START OF THIS PERIOD...BUT WE WILL STILL BE UNDER THE INFLUENCE
OF A VERY WET STORM SYSTEM. AN ELONGATED SFC LOW WILL MAKE ITS WAY
ACROSS NEW ENGLAND THURSDAY NIGHT...TAKING WITH IT THE DEEP LIFT
THAT WAS SUPPLIED BY A PAIR OF 150KT H25 JETLETS AND STRONG H925-70
FRONTOGENETIC FORCING FOUND WITHIN 100 MILES OR SO NORTH OF THE SFC
LOW TRACK. REMOVING THIS LIFT WHILE INTRODUCING MID LEVEL DRYING AND
SOME LOW LEVEL RIDGING WILL LEAD TO MIXED RAIN AND SNOW TAPERING OFF
TO SNOW SHOWERS DURING THE FIRST HALF OF THE NIGHT...WITH ONLY
NUISANCE SNOW SHOWERS EXPECTED DURING THE OVERNIGHT. ADDITIONAL QPF
WILL RANGE FROM LESS THAN A TENTH OF AN INCH OVER THE WESTERN
COUNTIES TO A COUPLE TENTHS OVER THE EASTERN LAKE ONTARIO REGION.
TOTAL RAINFALL FROM THE 12 HOUR EVENT WILL RANGE FROM A HALF TO
THREE QUARTERS OF AN INCH.
AS HAS BEEN ADVERTISED FOR SEVERAL DAYS...THIS AMOUNT OF RAINFALL
ALONG WITH CONTINUED SNOWMELT COULD LEAD TO PROBLEMS ON SOME
TRIBUTARIES...ESPECIALLY THE THREE MAIN WATERWAYS IN THE BUFFALO
AREA (CAZENOVIA, CAYUGA, BUFFALO CREEKS). FOR MORE INFORMATION ON
POTENTIAL HYDROLOGIC CONCERNS SEE THE HYDROLOGY SECTION BELOW.
ON FRIDAY...A SECONDARY COLD FRONTAL TROUGH WILL PUSH SOUTH ACROSS
THE LOWER GREAT LAKES. THIS WILL SUPPORT SCATTERED SNOW SHOWERS WITH
A BETTER CHANCE FOR STEADIER SNOWS ACROSS THE HIGHER TERRAIN IN THE
FAVORABLE COLD AIR ADVECTION/UPSLOPE REGIME. ACCUMULATIONS SHOULD BE
UNDER AN INCH...BUT HIGHER AMOUNTS WILL NOT BE OUT OF THE QUESTION
WEST OF THE FINGER LAKES. TEMPERATURES FRIDAY SHOULD BE A SOLID 10
DEG LOWER THAN THOSE FROM THE PREVIOUS DAY...AS MAX TEMPS ARE ONLY
EXPECTED TO TOP OUT WITHIN A COUPLE DEGREES OF FREEZING.
THE UPSLOPE...CYCLONIC FLOW WILL DELAY ANY REAL CLEARING FRIDAY
NIGHT AS THE MAIN UPPER LEVEL TROUGH WILL SWING ACROSS THE LOWER
GREAT LAKES. THERE SHOULD STILL BE SOME SCATTERED SNOW SHOWERS OVER
THE WESTERN COUNTIES...MAINLY WEST OF THE FINGER LAKES WHERE THE LOW
LEVEL FLOW WILL BE MORE CONDUCIVE FOR A LITTLE LAKE ENHANCEMENT OFF
ONTARIO. EVEN SO...ACCUMULATIONS WILL LIKELY BE MEASURED IN TENTHS
RATHER THAN INCHES. MEANWHILE...CONTINUED COLD ADVECTION SHOULD SEND
OVERNIGHT TEMPERATURES INTO THE TEENS AND PERHAPS EVEN THE SINGLE
DIGITS ACROSS PORTIONS OF THE SOUTHERN TIER AND EAST OF LAKE ONTARIO.
A SPRAWLING ARCTIC HIGH WILL DRIFT FROM THE UPPER GREAT LAKES TO THE
OHIO VALLEY ON SATURDAY. THIS WILL GUARANTEE AN ANOMALOUSLY COLD DAY
ACROSS OUR FORECAST AREA...AS TEMPERATURES ARE ONLY PROJECTED TO
REACH INTO THE MID AND UPPER 20S. THESE VALUES WILL BE SOME 20 DEG
BELOW NORMAL LATE MARCH VALUES. WHILE THE COLD AIR MAY BE
ACCOMPANIED BY SOME RESIDUAL LIGHT SNOW SHOWERS IN THE MORNING...
SKIES SHOULD CLEAR DURING THE COURSE OF THE DAY. THE INCREASED SUN
SHOULD HELP TO TEMPER AN OTHERWISE LATE JANUARY THERMOMETER.
ON SUNDAY...HIGH PRESSURE NOSING NORTH FROM THE MID ATLANTIC STATES
WILL KEEP OUR FORECAST AREA PCPN FREE. THE INCREASED SOUTHERLY FLOW
ON THE BACKSIDE OF THE SFC HIGH WILL PROMOTE NOTABLY MILDER
CONDITIONS AS WELL...WITH TEMPERATURES EXPECTED TO REACH THE LOWER
40S FOR MANY AREAS. A SHORTWAVE DROPPING SOUTHEAST ACROSS THE LOWER
GREAT LAKES SUNDAY NIGHT WILL THEN INTRODUCE THE NEXT ROUND OF SNOW
SHOWERS TO THE REGION.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
A PROGRESSIVE...LOW AMPLITUDE PATTERN WILL BE IN PLACE ACROSS THE
COUNTRY DURING THIS PERIOD...WITH A PARADE OF PACIFIC BASED
SHORTWAVES CROSSING THE GREAT LAKES REGION. WHILE TEMPERATURES WILL
BE COMFORTABLY HIGHER THAN THOSE EXPERIENCED THE PAST COUPLE
WEEKS...THE MERCURY WILL STILL AVERAGE A FEW DEGREES BELOW LATE
MARCH NORMALS.
DEEP LOW PRESSURE WILL PASS BY TO OUR NORTH TO OPEN THIS PERIOD.
WHILE THE MAIN COLD FRONT ASSOCIATED WITH THIS FEATURE IS FORECAST
TO MOVE THROUGH OUR REGION SUNDAY NIGHT...A SECONDARY COLD FRONT
WILL MOVE THROUGH DURING THE DAY MONDAY. THE MINIMAL SYNOPTIC
FORCING FROM THIS FEATURE WILL COMBINE IN THE UNSTABLE CHILLY
AIRMASS TO PRODUCE SOME RAIN AND WET SNOW SHOWERS...ALTHOUGH THE
BULK OF THE DAY WILL LIKELY BE PCPN FREE. IT IS NOT EXPECTED TO BE
COLD ENOUGH TO GET ANY LAKE ENHANCEMENT IN THIS EVENT.
ON TUESDAY...A ROBUST SHORTWAVE IS FORECAST TO TRACK FROM THE MID
WEST AND LOWER OHIO VALLEY TO THE MID ATLANTIC REGION. WHILE THE
BASE OF THE SUPPORTING LONGWAVE TROUGH CROSS OUR REGION...THE
RESULTING SYNOPTIC FORCING IS NOT EXPECTED TO BE STRONG ENOUGH TO
WARRANT ANYTHING MORE THAN SLGT CHC POPS FOR RAIN SHOWERS.
A BURGEONING RIDGE WILL THEN CROSS THE LOWER GREAT LAKES TUESDAY
NIGHT AND WEDNESDAY. WHILE THIS WILL LEAD TO MORE WARMING...THERE
WILL ALSO BE THE CHANCE FOR SOME SHOWERS AHEAD OF THE NEXT COLD
FRONTAL BOUNDARY.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
THERE IS A LOT OF MOISTURE IN THE LOWEST 2KFT DUE TO MOIST AIR
MOVING ACROSS THE COLD OR FROZEN LAKES. THIS MAY RESULT IN IFR CIGS
AND FOG NORTHEAST OF THE LAKES BUT THIS WILL BE DIFFICULT TO TIME.
EXPECT SLIGHTLY DRIER AIR AND DIMINISHING WINDS LIKELY TO RESULT IN
IMPROVING CONDITIONS LATE TONIGHT.
THIS IMPROVEMENT SHOULD BE SHORT LIVED AS ANOTHER WAVE OF LOW
PRESSURE TRACKS TO THE SOUTH AND BRINGS ABOUT 6 HOURS OF STEADY
PRECIPITATION DURING THE DAY THURSDAY. TEMPERATURES ALOFT WILL
LIKELY BE COLD ENOUGH FOR RAIN TO MIX WITH SNOW. THIS SHOULD LOWER
CIGS TO IFR OR LOWER...BUT THE WET SNOW AND RAIN MIX WILL PROBABLY NOT
LOWER VSBY AS MUCH AS AN EVENT WITH COLDER TEMPERATURES. CONDITIONS
WILL IMPROVE FROM SW-NE LATE IN THE DAY AS THE SYSTEM EXITS.
OUTLOOK...
THURSDAY NIGHT THROUGH FRIDAY NIGHT...MVFR WITH A CHANCE OF SNOW
SHOWERS.
SATURDAY AND SUNDAY...VFR.
MONDAY...MVFR IN RAIN/SNOW SHOWERS.
&&
.MARINE...
WEST TO NORTHWEST WINDS LATER THIS WEEK WILL INCREASE BEHIND A COLD
FRONT WITH SMALL CRAFT CONDITIONS POSSIBLE ON THE OPEN WATERS OF
LAKE ONTARIO LATER FRIDAY NIGHT.
&&
.HYDROLOGY...
A WARM FRONT BROUGHT ABOUT A TENTH OF AN INCH OF RAIN TO THE
RIVER AND CREEK BASINS. HIGH TEMPERATURES WERE ONLY IN THE LOWER TO MID
40S...AND EVEN A BIT COOLER THAN THAT IN THE SOUTHERN TIER. AS A
RESULT THE CREEK AND RIVER RESPONSE WILL PROBABLY BE A BIT LESS
THAN WHAT WAS EXPECTED.
THERE IS ANOTHER WAVE OF LOW PRESSURE WHICH SHOULD BRING ABOUT
ANOTHER HALF INCH OF QPF. HOWEVER...GUIDANCE HAS CONTINUED TO
TREND COLDER WITH THIS SYSTEM. TEMPERATURES ON THURSDAY MAY ONLY
BE IN THE UPPER 30S WHICH WOULD REDUCE RUN-OFF FROM SNOW MELT. THE
COOLER TEMPERATURE FORECAST HAS ALSO LOWERED THE EXPECTED THAWING
DEGREE HOURS TO ABOUT 250 TO 300.
ALTHOUGH THIS SHIFT IN MODEL GUIDANCE HAS DIMINISHED THE THREAT
FOR FLOODING...THE THREAT IS NOT COMPLETELY GONE. THERE WILL BE
SHARPLY WARMER AIR JUST TO THE SOUTH OF THE REGION...AND ANY
NORTHWARD SHIFT IN THIS WARM AIR COULD DRAMATICALLY INCREASE RUN-
OFF AND FLOWS. THERE IS ALSO QUITE A BIT OF ICE ALONG THE SHORES
OF THE CAZENOVIA AND BUFFALO CREEKS. IF LEVELS RISE TO ACTION
STAGE...THIS COULD CAUSE THIS ICE TO FLOAT AND BECOME JAMMED.
BECAUSE OF THIS...WE WILL CONTINUE TO KEEP A CLOSE EYE ON THE
SITUATION. IT IS STILL POSSIBLE THAT FLOOD WATCHES WILL BE NEEDED
FOR A PORTION OF THE AREA...ESPECIALLY IF THE LOW TAKES EVEN A
SLIGHTLY MORE NORTHWARD TRACK THAN WHAT IS CURRENTLY FORECAST.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...APFFEL/WCH
NEAR TERM...APFFEL/WCH
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...APFFEL
MARINE...CHURCH/WCH
HYDROLOGY...APFFEL/WCH
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
406 AM EDT THU MAR 26 2015
.SYNOPSIS...
A STRONG COLD FRONT WILL APPROACH FROM THE WEST TODAY AND CROSS THE
REGION EARLY FRIDAY. COLD HIGH PRESSURE WILL BUILD IN FROM THE WEST
OVER THE WEEKEND. A WEAK COLD FRONT WILL APPROACH FROM THE WEST MONDAY AND
MOVE OFFSHORE TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 355 AM THURSDAY...SHOWERS CONTINUE TO INCREASE IN COVERAGE
ACROSS THE FAR WESTERN CWA WITH SOME EMBEDDED THUNDERSTORMS NOTED
ALONG THE I-95 CORRIDOR. PER LATEST 3KM HRRR AND NSSL WRF
MODELS...THINK THIS PRECIPITATION WILL GRADUALLY INCREASE IN
COVERAGE AND SHIFT EASTWARD OVER THE NEXT SEVERAL HOURS ALONG BEST
AXIS OF SURFACE MOISTURE CONVERGENCE. WITH STRONG LOW-LEVEL
SHEAR...DESPITE MARGINAL INSTABILITY...SPC HAS COASTAL SECTIONS OF
OUR CWA IN A MARGINAL THREAT OF SEVERE WEATHER TODAY...WITH THE
MAIN THREAT TIME BEING THROUGH MIDDAY...WITH STRONG WINDS BEING
THE PRIMARY THREAT. MOST ALL OF THE MODELS SHOW PRECIPITATION
DIMINISHING DURING THE AFTERNOON HOURS AND HAVE SCALED BACK TO A
SLIGHT CHANCE AS WEAK SUBSIDENCE PREVAILS. WITH A GOOD DEAL OF
SUNSHINE LATER IN THE AFTERNOON...GUSTY SOUTHWEST WINDS WILL DRIVE
VERY WARM TEMPERATURES INLAND WITH HIGHS IN THE 75 TO 80 DEGREE
RANGE AWAY FROM THE IMMEDIATE COAST...BUT IN THE UPPER 60S/LOWER
70S IN COASTAL AREAS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
AS OF 4 AM THURSDAY...AS STRONG COLD FRONT ADVANCE TOWARD THE AREA
DURING THE LATE EVENING...LIGHT PRECIPITATION WILL DEVELOP ACROSS
MOST OF THE REGION AND SCALE POPS BACK UP TO HIGH CHANCE THROUGH
ABOUT 06Z AND LIKELY THROUGH FRIDAY MORNING. ATMOSPHERE WILL BE
RELATIVELY STABLE BY THIS TIME...WITH PERHAPS ELEVATED THUNDER
ACROSS ADJACENT SOUTHERN COASTAL WATERS. GUSTY SOUTHWESTERLY WINDS
AHEAD OF THE FRONT WILL HOLD TEMPERATURES IN THE LOWER 60S COAST
AND MID/UPPER 50S INLAND...BEFORE TEMPERATURES DROP BEHIND THE
FRONT DURING THE DAY ON FRIDAY.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 330 AM THUR...WET PATTERN TO START THE
PERIOD...THEN FREEZING TEMPS EXPECTED THIS WEEKEND...FOLLOWED BY
WARMING TEMPS NEXT WEEK.
FRIDAY...MODELS IN GOOD AGREEMENT WITH COLD FRONT PASSING THROUGH E
NC FROM NW TO SE THROUGH THE MORNING. OVERRUNNING PRECIP AS 850 MB
FRONT WILL HANG BACK INDUCING FGEN AND CONTINUED WIDESPREAD RAIN
SHOWERS ALL DAY. USED A NON-DIURNAL TEMP CURVE...AS HIGH TEMPS
REALIZED EARLY IN THE MORNING BEFORE FALLING THROUGH THE 40S AND 50S
DURING THE LATE MORNING/EARLY AFTERNOON. IT WILL BE RAW WITH GUSTY
NORTH WINDS AND WIDESPREAD RAIN AFTER THE FRONT PASSES.
FRIDAY NIGHT...THICKNESSES FALL AS UPR TROUGH PIVOTS INTO EASTERN NC
AND 850 MB FRONT PASSES OFFSHORE. WIDESPREAD RAIN WILL QUICKLY MOVE
OFFSHORE IN THE EVENING...FOLLOWED BY JUST ISOLATED SHOWERS THROUGH
THE EVENING. TEMPS WILL STEADILY FALL INTO THE 30S BY LATE FRI
NIGHT. FCST MODEL SNDGS INDICATE A SHALLOW SFC TO 1500 FT WARM
LAYER...THOUGH WET BULB TEMPS JUST ABOVE THIS LAYER AND CONTINUED
SATURATION IN THE DGZ SUGGEST A MIX WITH SNOW SHOWERS MAY OCCUR IF
PRECIP DOES IN FACT OCCUR. NO IMPACTS WOULD OCCUR HOWEVER AS SFC
TEMPS AND GROUND TEMPS ABOVE FREEZING.
SATURDAY...ANY SNOW/RAIN SHOWERS WOULD QUICKLY END SAT MORNING AS
DRY AIR WORKS IN AND SUNSHINE RETURNS. BREEZY AND COOL CONDITIONS
WITH ARCTIC HIGH PRES BUILDING IN FROM NW...AND THICKNESSES
SUGGESTING HIGHS FROM MID 40S NRN OBX TO TO UPR 40S TO NEAR 50
SOUTHWEST.
SATURDAY NIGHT...THE ARCTIC HIGH PRES AREA BUILDS INTO E NC WITH A
FREEZE EXPECTED MOST AREAS AWAY FROM THE IMMEDIATE COAST AS IDEAL
RADIATIONAL COOLING REGIME IN PLACE. BEACHES MAY SEE ENOUGH WIND
TO KEEP TEMPS ABOVE FREEZING. GROWING SEASON WILL OFFICIALLY BEGIN
ON MARCH 27 ACROSS ALL OF E NC SO WILL LIKELY HAVE TO CONTEND WITH
FROST/FREEZE HEADLINES SAT NIGHT/SUN MORNING.
SUNDAY...MODERATING TEMPS THOUGH STILL BELOW CLIMO WITH HIGHS IN THE
MID 50S (UPR 40S OBX) THOUGH WINDS MUCH LIGHTER AND VEERING TO THE
WEST SO WILL FEEL PLEASANT WITH THE STRONG LATE MARCH SUN.
SUNDAY NIGHT INTO MONDAY NIGHT...RETURN GUSTY SW FLOW BRINGS
CONTINUED MODERATION IN TEMPS SUN NIGHT INTO MONDAY. SOME MODEL
DISCREPANCIES COME INTO PLAY WITH FAST MOVING COLD FRONT EARLY IN
THE WEEK. 26/00Z GFS INDICATES AN EARLY FROPA WITH SHOWER CHANCES AS
EARLY AS LATE SUN NIGHT...THOUGH ECMWF AND CMC HAVE A SLIGHTLY
SLOWER SOLN WITH PASSAGE OF FRONT LATER MONDAY. WILL KEEP POPS LOW
MON/MON NIGHT ONLY 20 PERCENT FOR NOW DUE TO LIMITED MOISTURE RETURN
AND TIMING DIFFERENCES.
TUESDAY THROUGH MID WEEK...WARMING TREND EXPECTED TO CONTINUE WITH
ZONAL FLOW AND TEMPS NEAR TO ABOVE CLIMO WITH HIGHS UPR 60S TO LOWER
70S WITH GENERALLY DRY CONDITIONS.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
SHORT TERM /THROUGH 06Z FRIDAY/...
AS OF 115 AM THURSDAY...GENERALLY VFR CONDITIONS AT THE
TAF SITES CURRENTLY AS CLOUD COVER PRIMARY MID/HIGH CLOUDS WITH
SOME SCATTERED STRATOCUMULUS. AS SHOWERS INCREASE FROM THE SOUTH
TOWARD MORNING...STILL EXPECT A PERIOD OF MVFR VSBYS AND CEILINGS
UNTIL LATE MORNING OR EARLY AFTERNOON. GUSTY S/SW WINDS ARE
EXPECTED TO DEVELOP TOWARD DAYBREAK AND CONTINUE INTO THURSDAY
AFTERNOON. NO MAJOR CHANGES MADE THIS TAF CYCLE.
LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 330 AM THUR...GOOD THREAT OF MVFR TO
IFR CIGS FRIDAY AS STRONG FRONTAL INVERSION SETS UP WITH WIDESPREAD
RAIN AND LOW CLOUDS. IMPROVING CONDITIONS FRIDAY NIGHT AS MOISTURE
MOVES OFFSHORE WITH JUST A SLIGHT CHANCE OF PRECIP FRI NIGHT INTO
SAT MORNING. WINDS BECOME GUSTY NORTHERLY ON FRIDAY BEHIND THE
FRONT...AND CONTINUE GUSTY NW ON SATURDAY. HIGH PRES BUILDS SATURDAY
NIGHT INTO SUNDAY WITH MAINLY CLEAR SKIES AND LIGHT WINDS. ANOTHER
FRONT PASSES THROUGH ON MONDAY THOUGH LOOKS TO REMAIN VFR WITH JUST
A SLIGHT CHANCE OF RAIN AT THIS TIME.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 4 AM THURSDAY...SOUTHEAST TO SOUTH WILL GRADUALLY INCREASE
THIS MORNING AND BECOME SOLIDLY IN SMALL CRAFT ADVISORY RANGE THIS
AFTERNOON AS THEY VEER TO SOUTHWEST AND INCREASE TO 20 TO 30
KNOTS. SEAS LIKEWISE WILL BUILD TO AS HIGH AS 7 TO 10 FEET BY
MIDDAY...ESPECIALLY OVER THE OUTER WATERS. THESE GUSTY WINDS AND
ROUGH SEAS CONTINUE TONIGHT AS A STRONG COLD FRONT ADVANCES TOWARD
OUR WATERS AND MOVES OFFSHORE BY MID-MORNING FRIDAY.
LONG TERM /FRIDAY THROUGH MONDAY/...
PREVIOUS FCST ON TRACK WITH ACTIVE PATTERN PRODUCING POOR BOATING
CONDITIONS TO START THE PERIOD. SHARP COLD FRONT WILL PASS THROUGH
THE WATERS ON FRIDAY FROM NORTH TO SOUTH. GUSTY NORTH WINDS 25 TO
30 KT BEHIND THE FRONT WILL DEVELOP AND CONTINUE THE SCA
CONDITIONS. THESE GUSTY WINDS WILL CONTINUE INTO SATURDAY AS WINDS
VEER NORTHWEST WHILE ONLY SLOWLY DIMINISHING AS COLD AIR CONTINUES
TO POUR INTO E NC. HIGH PRES BUILDS IN ON SUNDAY AND WINDS BECOME
LIGHT. WINDS CONTINUE TO VEER AND BECOME SOUTHWEST INCREASING TO
NEAR SCA ON MONDAY AHEAD OF NEXT FRONTAL SYSTEM.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 2 AM EDT
FRIDAY FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 9 AM EDT SUNDAY FOR AMZ152-154-156.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT SATURDAY FOR AMZ150.
SMALL CRAFT ADVISORY UNTIL 3 AM EDT SATURDAY FOR AMZ158.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC
SHORT TERM...CTC
LONG TERM...TL
AVIATION...CTC/TL
MARINE...CTC/TL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
111 AM EDT THU MAR 26 2015
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFFSHORE TONIGHT. A COLD FRONT WILL
APPROACH FROM THE WEST THURSDAY AND CROSS THE REGION EARLY FRIDAY.
COLD HIGH PRESSURE WILL BUILD IN FROM THE WEST OVER THE WEEKEND. A
WEAK COLD FRONT WILL APPROACH FROM THE WEST MONDAY AND MOVE
OFFSHORE TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 105 AM THURSDAY...A FEW SPOTTY SHOWERS IMPACTING AREAS NEAR
THE COAST AND WEST OF HIGHWAY 17. LATEST RUN OF THE 3KM HRRR SHOW
THIS ACTIVITY PERSISTING AND INCREASING OVER THE NEXT FEW HOURS
BEFORE BUILDING EAST TOWARD MORNING. HAVE 20-30 PCT POPS OVER THE
REGION...INCREASING TO HIGH CHANCE AFTER 08Z. INSTABILITY IS QUITE
WEAK ACROSS THE REGION AND REMOVED MENTION OF THUNDER UNTIL AFTER
08Z. NO OTHER MAJOR CHANGES TO THE FORECAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
AS OF 245 PM WEDNESDAY...GOOD CVRG OF SHRA AND A FEW TSRA EXPECTED
THRU MORNING ESPCLY CST WITH CONT DECENT LIFT AND MOISTURE OVER
REGION. THE MOISTURE SLIDES OFFSHORE DURING LATE MORN AND EARLY
AFTN WITH INCREASING SUNSHINE DURING AFTN. INSTAB WILL BE
INCREASING DURING AFTN WITH GOOD HEATING ESPCLY INLAND. GFS NOW
SHOWS A LITTLE MORE INSTAB ALTHOUGH STILL WELL BELOW WHAT NAM IS
INDICATING. ALTHOUGH BEST CVRG OF SHRA WILL BE EARLY BEST CHC OF
STRONG TO POSS SEVERE STORMS WILL LIKELY BE IN AFTN WHEN INSTAB
INCREASES OVER THE AREA. GIVEN FAVORABLE SHEAR OVER REGION ANY
INCREASE IN INSTAB WOULD LEAD TO GREATER SEVERE THREAT WITH SOME
STORMS POSS ROTATING. NO CHANGE TO HIGHS WITH AROUND 80 INLAND TO
60S BEACHES.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 141 PM WED...MODELS IN GOOD AGREEMENT BOTH AT THE SURFACE AND
ALOFT INTO THE WEEKEND. UPPER RIDGE WELL OFFSHORE WITH FULL LATITUDE
TROUGHING OVER THE CENTRAL PART OF THE COUNTRY WILL START THE
PERIOD. TROUGH APPROACHES THE EAST COAST THROUGH THE END OF THE
WEEK. STARTING TO SEE SOME SPREAD IN THE MODELS LATE SATURDAY AS
ECMWF SLOWS THE TROUGH. AT THE SURFACE A STRONG FRONT MOVES THROUGH
EASTERN NORTH CAROLINA THURSAY NIGHT. MODELS WITHIN A FEW HOURS OF
EACH OTHER ON THE FRONTAL PASSAGE. SMALL PIECES OF ENERGY IN THE
SOUTHWEST UPPER FLOW WILL KEEP PRECIPITATION CHANCES GOING FRIDAY
BEHIND THE FRONT AS THE UPPER TROUGH AND ASSOCIATED UPPER LEVEL
ENERGY APPROACHES AND 850 FRONT MOVES THROUGH LATE FRIDAY.
WILL SEE DECREASING CHANCES OF PRECIPITATION FRIDAY NIGHT AS HIGH
PRESSURE AT THE SURFACE BUILDS IN FROM THE WEST AND 850 FRONT MOVES
EAST OF THE AREA. COOLING OF THE ATMOSPHERIC COLUMN FRIDAY NIGHT AS
DEEP UPPER TROUGH MOVES THROUGH THE AREA. FORECAST SOUNDINGS SHOWING
NEAR SURFACE TEMPERATURES NEAR FREEZING. WITH NEARLY SATURATED LOWER
LEVELS MAY NOT SEE MUCH EVAPORATIVE COOLING. HOWEVER WITH SURFACE
TEMPERATURES THIS CLOSE TO FREEZING AND A SMALL POTENTIAL OF
EVAPORATIVE COOLING...COULD SEE SOME WINTERY TYPE PRECIPITATION.
VARIOUS DEGREES OF SATURATION IN THE DENDRITIC GROWTH ZONE.
CONDITIONS ARE MARGINAL GIVING LOW CONFIDENCE...SINCE MIXTURE
ALREADY IN FORECAST...WILL NOT MAKE ANY CHANGES. IF ANY WINTERY
PRECIPITATION DOES FORM...WARM GROUND TEMPERATURES WILL LIMIT ANY
IMPACTS.
PRECIPITATION CHANCES SHOULD BE OUT OF THE AREA BY SUNRISE SATURDAY.
HIGH PRESSURE AT THE SURFACE WILL KEEP NORTHERLY FLOW OVER THE AREA
FOR HIGH TEMPERATURES ONLY IN THE 40S ON SATURDAY. COOL TEMPERATURES
REMAIN SATURDAY NIGHT WITH LOWS DROPPING INTO INTO THE UPPER 20S TO
LOWER 30S.
WEAK UPPER LEVEL RIDGE OVER THE SOUTHEAST WILL MOVE OUT OF THE AREA
SUNDAY NIGHT WITH SURFACE HIGH PRESSURE MOVE OFFSHORE...ALLOWING LOW
LEVEL FLOW TO BECOME SOUTHERLY. SOME DIFFERENCES IN MODELS START AT
THE BEGINNING OF THE WEEK. FRONTAL SYSTEM APPROACHING WITH MODELS
DISAGREEING ON TIMING AND STRENGTH. FOR NOW WILL LEAN TOWARDS A
DRIER SOLUTION. HIGH PRESSURE BACK OVER THE AREA BY WEDNESDAY.
&&
.AVIATION /05Z THURSDAY THROUGH MONDAY/...
SHORT TERM /THROUGH 06Z FRIDAY/...GENERALLY VFR CONDITIONS AT THE
TAF SITES CURRENTLY AS CLOUD COVER PRIMARY MID/HIGH CLOUDS WITH
SOME SCATTERED STRATOCUMULUS. AS SHOWERS INCREASE FROM THE SOUTH
TOWARD MORNING...STILL EXPECT A PERIOD OF MVFR VSBYS AND CEILINGS
UNTIL LATE MORNING OR EARLY AFTERNOON. GUSTY S/SW WINDS ARE
EXPECTED TO DEVELOP TOWARD DAYBREAK AND CONTINUE INTO THURSDAY
AFTERNOON. NO MAJOR CHANGES MADE THIS TAF CYCLE.
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 149 PM WED...SUB-VFR CONDITIONS EXPECTED INTO FRIDAY NIGHT AS
COLD FRONT MOVES THROUGH THE AREA THURSDAY NIGHT AND MID LEVEL FRONT
CONTINUES OVER THE AREA INTO SATURDAY MORNING BRINGING SHOWERS.
THERE MAY BE SOME INSTABILITY AHEAD OF THE FRONT FOR A CHANCE OF
THUNDERSTORMS. VFR CONDITIONS EXPECTED SATURDAY THROUGH MONDAY.
&&
.MARINE...
SHORT TERM /TONIGHT AND THU/...
AS OF 110 AM THURSDAY...WINDS GENERALLY SE AT 15 KNOTS OR LESS
CURRENTLY...BUT SPEEDS WILL GRADUALLY INCREASE TOWARD MORNING WITH
SEAS BUILDING TO 6 FEET OR BETTER BY DAYBREAK. NO MAJOR CHANGES
WITH THIS UPDATE.
LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 155 PM WED...ACTIVE PATTERN INTO THE WEEKEND WILL KEEP THINGS
STIRRED UP OVER THE EASTERN NORTH CAROLINA COASTAL WATERS. STRONG
COLD FRONT WILL MOVE THROUGH THE WATERS FRIDAY MORNING. TIGHT
PRESSURE GRADIENT AHEAD OF THE FRONT WILL KEEP ALL WATERS IN THE
SMALL CRAFT ADVISORY CRITERIA. GRADIENT WILL RELAX BEHIND THE FRONT
WITH NORTHERLY FLOW IN THE 15 TO 20 KNOT RANGE. SEAS WILL REMAIN
ELEVATED OVER MUCH OF THE WATERS THROUGH FRIDAY NIGHT...AND OVER THE
OUTER WATERS INTO SATURDAY NIGHT AS HIGH PRESSURE BUILDS INTO THE
AREA.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 2 AM EDT
FRIDAY FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 9 AM EDT SUNDAY FOR AMZ152-154-156.
SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 11 PM EDT
SATURDAY FOR AMZ150.
SMALL CRAFT ADVISORY UNTIL 3 AM EDT SATURDAY FOR AMZ158.
&&
$$
SYNOPSIS...RF
NEAR TERM...CTC
SHORT TERM...RF
LONG TERM...CCG
AVIATION...CCG/CTC
MARINE...CCG/CTC/JBM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
128 AM CDT THU MAR 26 2015
.UPDATE...
ISSUED AT 128 AM CDT THU MAR 26 2015
MODELS ON TRACK WITH A BAND OF SNOW DEVELOPING AND MOVING THROUGH
WESTERN NORTH DAKOTA OVERNIGHT THROUGH MID MORNING THURSDAY.
ADJUSTED POPS TO MATCH LATEST RADAR IMAGERY AND HIGH RES MODELS.
AN INCH TO INCH AND ONE HALF POSSIBLE. WILL MENTION SOMETHING IN
THE HWO AS SOME TRAVEL ISSUES MAY MATERIALIZE EARLY THIS MORNING.
WINTRY MIX IS THEN POSSIBLE THURSDAY NIGHT AS A WARM FRONT MOVES
EAST INTO THE REGION.
UPDATE ISSUED AT 945 PM CDT WED MAR 25 2015
THE FORECAST FOR THE REMAINDER OF THE NIGHT REMAINS ON TRACK AND
IN LINE WITH THE 23-01 UTC HRRR ITERATIONS AND INCOMING 00 UTC
NAM...DEVELOPING A BAND OF LIGHT SNOW ACROSS THE SOUTHWEST.
ALTHOUGH...THE NAM HAS THE MOST AMPLIFIED QPF FIELD...AND THUS DID
SHY AWAY FROM ITS OVERALL AMOUNTS.
UPDATE ISSUED AT 710 PM CDT WED MAR 25 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE OTHER THAN TO
INCREASE POPS ACROSS THE SOUTHWEST LATE TONIGHT GIVEN GOOD RUN TO
RUN CONSISTENCY AMONGST THE 20-22 UTC HRRR ITERATIONS OF A BAND
OF LIGHT SNOW DEVELOPING IN ASSOCIATION WITH THE BAROCLINIC ZONE
ON THE WESTERN PERIPHERY OF THE SURFACE RIDGE AXIS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 350 PM CDT WED MAR 25 2015
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE A WINDS
IN THE FAR EAST LATE THIS AFTERNOON...THEN PRECIPITATION CHANCES
LATE TONIGHT AND THURSDAY MORNING IN THE WEST ASSOCIATED WITH A
SHORTWAVE DROPPING ACROSS THIS AREA IN NORTHWEST FLOW.
CURRENTLY...WINDS GUSTING TO 43 MPH AT JAMESTOWN...WITH GUSTS TO
41 MPH AT CARRINGTON LAST HOUR. SOME PEAKS OF SUN PROBABLY ADDING
TO THE INCREASED MIXING. BUT GRADIENT WINDS WILL CONTINUE TO
SLACKEN AND FALL/RISE COUPLET HAS ALREADY PUSHED INTO THE RED
RIVER VALLEY. WILL KEEP THE ADVISORY GOING THROUGH THE 5 PM
EXPIRATION AND EXPECT WINDS TO DIMINISH BELOW CRITERIA BY THIS
TIME WITH A QUICK DROP OFF THIS EVENING. HIGH PRESSURE SITUATED
OVER EASTERN MONTANA WILL DRIFT EASTWARD INTO THE WESTERN DAKOTAS.
TONIGHT...NORTHWEST FLOW WILL QUICKLY DEVELOP OVER THE MONDAY
REGION TONIGHT. A IMPULSE MOVING THROUGH THE FLOW WILL INDUCE
SURFACE LOW PRESSURE OVER EASTERN MONTANA...WITH WEAK ISENTROPIC
UPGLIDE OVER WESTERN NORTH DAKOTA. THIS WILL RESULT IN A BAND OF
LIGHT PRECIPITATION DROPPING SOUTHEAST ACROSS WESTERN NORTH DAKOTA
LATE TONIGHT INTO THURSDAY MORNING. CURRENT BUFKIT SOUNDINGS
UTILIZING THE MAXIMUM WET BULB TEMPERATURE ALOFT INDICATES SNOW
TONIGHT AND A MIX OF RAIN AND SNOW THURSDAY. SNOW RATIOS ARE LOW
AND THUS WE ARE GETTING SNOW AMOUNTS OF AN INCH OR LESS FROM
AROUND TROTTERS SOUTHEAST THROUGH DICKINSON TO HETTINGER. SNOW IS
EXPECTED TO END BY MIDDAY THURSDAY. SHOULD BE WARMER THURSDAY WITH
MAINLY 30S EAST TO 40S SOUTHWEST.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 350 PM CDT WED MAR 25 2015
THE LONG TERM WILL BE CHARACTERIZED BY A PROGRESSIVE FLOW WITH
SEVERAL LOW PRESSURE SYSTEMS TRAVERSING THE FORECAST AREA.
THURSDAY NIGHT AND FRIDAY:
COOL HIGH PRESSURE WILL BE IN PLACE OVER THE EASTERN DAKOTAS
THURSDAY NIGHT. A WARM FRONT IS FORECAST TO APPROACH THE WESTERN
BORDER OF NORTH DAKOTA THURSDAY NIGHT...AND MOVE EASTWARD ACROSS THE
STATE ON FRIDAY. PRECIPITATION IS EXPECTED ALONG AND EITHER SIDE OF
THE WARM FRONT. THE WARM ADVECTION MOVING IN FROM THE WEST WILL BE
CHARACTERIZED BY A WARM LAYER ABOVE THE SURFACE LEADING/AHEAD OF THE
WARMING AT THE SURFACE. THIS WILL RESULT IN A CHANCE OF LIGHT SNOW
AHEAD OF THE FRONT...A NARROW BAND ALONG THE WARM FRONT WITH CHANCES
OF FREEZING RAIN...FOLLOWED BY CHANCES OF RAIN BEHIND THE WARM
FRONT. LOWS THURSDAY NIGHT SHOULD RANGE FROM THE TEENS EAST TO THE
LOWER 30S SOUTHWEST...WITH HIGHS FRIDAY FROM AROUND 40 EAST TO THE
LOWER 60S SOUTHWEST.
A WARM DAY SATURDAY WITH HIGHS IN THE UPPER 50S TO UPPER 60S. THE
APPROACH OF AN UPPER LEVEL LOW MOVING EAST ACROSS THE ROCKIES WILL
DEVELOP A SURFACE LOW THAT ENTERS WESTERN NORTH DAKOTA SATURDAY
AFTERNOON. THIS WILL BRING A SLIGHT CHANCE OF LIGHT RAIN TO THE WEST
SATURDAY AFTERNOON...AND A BETTER CHANCE OF LIGHT RAIN SATURDAY
NIGHT AS THE SYSTEM MOVES ACROSS THE AREA.
GENERALLY MILD AND DRY SUNDAY AND MONDAY...THEN THE APPROACH OF
ANOTHER SHORTWAVE MOVING EAST ACROSS THE ROCKIES WILL BRING CHANCES
OF PRECIPITATION TUESDAY INTO WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 128 AM CDT THU MAR 26 2015
VFR CEILINGS IN SCT-BKN AREAS OF STRATUS CENTRAL AND EAST. IFR
CONDITIONS ARE LIKELY IN SNOW AND LOW STRATUS AS A BAND OF LIGHT
SNOW DEVELOPS FROM KISN SOUTH-SOUTHEAST TO KDIK EARLY THIS
THURSDAY MORNING. STRATUS LINGERS UNTIL MID MORNING. REDEVELOPMENT
OF MVFR-IFR CIGS EXPECTED THURSDAY NIGHT WEST INTO CENTRAL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...TWH
LONG TERM...TWH
AVIATION...NH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
317 AM EDT THU MAR 26 2015
.SYNOPSIS...
LOW PRESSURE LIFTS NORTHEAST THROUGH UPPER OHIO VALLEY THIS MORNING.
STRONG COLD FRONT CROSSES THIS AFTERNOON. MUCH COLDER AIR DOMINATES
LATE TONIGHT THROUGH SUNDAY MORNING.
&&
.NEAR TERM /THROUGH TONIGHT/...
LEANED FAIRLY HEAVILY ON THE HRRR INTO THIS AFTERNOON. SURFACE
BOUNDARY HAS DEVELOPED ACROSS OHIO...AND IS APPARENT IN THE OBS.
KZZV HAS A SE WIND WHILE KOSU IS NORTHERLY. THIS PUTS THE BOUNDARY
JUST TO THE NW OF PERRY COUNTY. A SOMEWHAT ELONGATED SURFACE WAVE IS
MOVING UP THE FRONT...CURRENTLY IN WESTERN KY/TN. EXPECT THIS WAVE
TO CROSS WESTERN CWA THIS MORNING...THEN AS IT CONTINUES TO THE NE
IT WILL DRAG COLD FRONT THROUGH THIS AFTERNOON AND EVENING. HAVE
HIGHEST POPS JUST BEHIND THE FRONT. PREVIOUS FORECAST TIMING STILL
LOOKS PRETTY GOOD...SO NO SIGNIFICANT CHANGES THERE. HAVE THE FRONT
CROSSING THE OHIO RIVER 17Z-18Z. NEAR THE I-79 CORRIDOR FROM CRW TO
CKB AROUND 19Z-20Z. MAKING IT INTO THE MOUNTAINS 21Z-22Z...AND THEN
HEADED EAST OF CWA BY 00Z. DID TIGHTEN UP THE POP GRADIENT...AND
HAVE DRY POPS MAKING IT TO THE OHIO RIVER BY THE END OF NEAR TERM.
HAVE A PERIOD OF THUNDER POSSIBLE ALONG THE FRONT. WENT WITH
NON-DIURNAL TEMPS ACROSS THE WEST...AS TEMPERATURES BEGIN TO COOL
BEHIND THE FRONT THIS AFTERNOON. BUMPED UP HIGHS ACROSS THE EAST A
LITTLE WITH GOOD SOUTHERLY FLOW AND A TIGHTER POP GRADIENT KEEPING
THINGS DRY THERE A BIT LONGER...PLUS MANY HAVE ONLY COOLED INTO THE LOW
TO MID 50S SO FAR EARLY THIS MORNING.
COLD AIR CONTINUES TO WORK IN BEHIND THE FRONT TONIGHT. HAVE RAIN
CHANGING OVER TO SNOW...WITH POSSIBLY A LITTLE SLEET IN SOME
LOCATIONS RIGHT AROUND THE TRANSITION TIME. ENDED UP WITH ABOUT AN
INCH OF SNOW BY 12Z AT THE HIGHER ELEVATIONS OF THE NORTHERN
MOUNTAINS...WITH A COATING TO HALF INCH IN MOUNTAIN VALLEYS ACROSS
THE EASTERN CWA.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
OLD MAN WINTER`S ENCORE APPEARANCE LINGERS INTO SUNDAY MORNING.
NO BIG CHANGES MADE TO OUR FORECAST FOR THIS SHORT TERM. THE BOARD
500 MB TROF SHARPENS WITH ITS AXIS NOT PASSING UNTIL 08Z TO 12Z
SATURDAY. THE 850 MB THERMAL TROF HANGS OVER US INTO THE DAY ON
SATURDAY...BUT WITH TEMPERATURES MODERATING A FEW DEGREES ON
SATURDAY. THE COLDEST 850 MB TEMPERATURES ARE FRIDAY NIGHT TO 12Z
SATURDAY...WITH BEST CRYSTAL GROWTH TEMPERATURES IN THE LINGERING
LOW LEVEL MOISTURE. SO CONTINUE TO HAVE POPS HIGHER THAN BOTH NAM
AND GFS MOS GUIDANCE FOR THE WV MOUNTAIN COUNTIES.
IN TERMS OF SHOWER COVERAGE...STILL THINKING A SEMI LULL IN PCPN
COVERAGE 12Z TO 16Z FRIDAY...THEN INCREASING FOR FRIDAY AFTERNOON
AND FRIDAY EVENING...WITH BEST CHANCE OF GROUND WHITENING IN THE
LOWLANDS LATE FRIDAY AFTERNOON OR FRIDAY EVENING. HAVE A FEW INCHES
OF SNOW ACCUMULATION OVER THE CENTRAL WV MOUNTAINS. HARD TO TELL
HOW MUCH THE SNOW SHOWERS WILL DIURNALLY DECREASE OVERNIGHT FRIDAY
NIGHT.
AS WE MENTIONED YESTERDAY...STILL THINKING NOT SOLID OVERCAST ON
FRIDAY...BUT CELLULAR FOR THIS TIME OF THE YEAR. SO STILL TRYING TO
LEAK THE LOWLAND TEMPERATURES UP INTO THE LOWER 40S BETWEEN SHOWERS.
YET...WITH THE COLD AIR ALOFT...LEFT THE POSSIBLE OF SNOW OR RAIN
SHOWERS EVEN WITH TEMPERATURES AROUND 40 DEGREES.
HIGH PRESSURE AND A CLEARER NIGHT EXPECTED FOR SATURDAY NIGHT/SUNDAY
MORNING. FORECAST TEMPERATURES NEAR RECORD LOWS FOR MARCH 29TH.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ROLLER COASTER RIDE IN THE TEMP DEPARTMENT TO CONTINUE THRU THE
EXTENDED PERIODS. SURFACE HIGH AND A VERY DRY AIRMASS WILL ALLOW
FOR IDEAL RADIATIONAL COOLING SATURDAY NIGHT WITH MANY PLACES
DIPPING INTO THE TEENS. TRIED TO HIT THE TYPICAL COLD SPOTS HARD
WHILE KEEPING AREAS ALONG BIG RIVERS A FEW DEGREES HIGHER THAN
GUIDANCE SUGGESTS. A NICE REBOUND WILL BE REALIZED ON SUNDAY AMID WAA
ALOFT ON STRENGTHENING SW FLOW. A FAST MOVING COLD FRONT WILL
SLIDE THRU SUNDAY NIGHT WITH A CHANCE FOR SHOWERS. A WAVE MAY
DEVELOP IN THE TN VALLEY ON MONDAY WHICH WOULD KEEP THE RAIN
THREAT GOING ACROSS SW VA AND SE WV. TEMPS WILL COME BACK DOWN
BEHIND THE FRONT AS NW FLOW ALOFT BECOMES ESTABLISHED BEHIND A
CLIPPER SYSTEM EARLY TUESDAY...WITH A SMALL CHANCE FOR A SHOWER
AND SNOW SHOWER FOR THE N MOUNTAINS. UPPER HEIGHTS WILL QUICKLY
REBOUND MIDWEEK WITH DECENT WAA CRANKING ONCE AGAIN...AHEAD OF THE
NEXT FRONT. AS A RESULT...TEMPS SHOULD SPIKE INTO THE 70S ONCE
AGAIN LONG ABOUT WEDNESDAY.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS CURRENTLY IN PLACE. PRECIPITATION MOVING INTO SW
OHIO. THIS PRECIP WILL CONTINUE EXPANDING NE ALONG A BOUNDARY THAT
WILL EVENTUALLY SINK SOUTHWEST AS A COLD FRONT DURING THE DAYLIGHT
HOURS. HAVE THUNDER POSSIBLE RIGHT ALONG THE FRONT...WITH MVFR IN
RAIN FOR SEVERAL HOURS BEHIND THE FRONT. WINDS WILL INCREASE OUT
OF THE SOUTH AHEAD OF THE FRONT...SWITCHING TO GUSTY NW BEHIND THE
FRONT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF RESTRICTIONS IN CLOUDS AND
PRECIPITATION ON THURSDAY 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 03/26/15
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
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 L L L L L L L L 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 06Z FRIDAY...
IFR POSSIBLE IN CIGS BEHIND THE COLD FRONT THU NIGHT IN THE
MOUNTAINS. IFR ALSO POSSIBLE LATE THURSDAY NIGHT INTO FRIDAY
ACROSS NRN WV AND DOWN THROUGH THE MOUNTAINS IN MIXED RAIN AND
SNOW SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/TRM/MZ
NEAR TERM...MZ
SHORT TERM...KTB
LONG TERM...30
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
137 AM EDT THU MAR 26 2015
.SYNOPSIS...
LOW PRESSURE CROSSES THE MIDDLE OHIO VALLEY THURSDAY MORNING. THIS
DRAGS A STRONG COLD FRONT THROUGH THE AREA MIDDAY AND AFTERNOON.
MUCH COLDER AIR DOMINATES THURSDAY NIGHT THROUGH SUNDAY MORNING.
&&
.NEAR TERM /THROUGH TODAY/...
SATELLITE TRENDS AND THE HRRR MODEL INDICATE THAT CLOUDS WILL NOT BE
VERY ABUNDANT LATE THIS AFTERNOON AND EARLY THIS EVENING. WILL
UPDATE THE FORECAST TO BETTER REFLECT THIS.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
COLD FRONT SHOULD BE EAST OF THE REGION AT THE BEGINNING OF THE
PERIOD. THIS FEATURE WILL CONTINUE TO PUSH EAST. HOWEVER...SURFACE
HIGH PRESSURE WILL TAKE AWHILE TO BUILD IN AS UPPER LEVEL TROF WILL
LAG BEHIND THE SURFACE FEATURE.
CURRENT THINKING IS THAT PRECIPITATION CHANCES WILL SLOWLY DECREASE
BEHIND THE FRONT AND THEN INCREASE LATE FRIDAY INTO FRIDAY NIGHT AS
THE UPPER TROF APPROACHES. PRECIP CHANCES SHOULD THEN DECREASE
FRIDAY NIGHT...WITH DRY CONDITIONS EXPECTED BY MID-DAY ON SATURDAY.
SINCE UPPER TROF DOES NOT ACTUALLY PUSH EAST UNTIL LATE FRIDAY NIGHT
INTO SATURDAY...MAY NOT HAVE HELD ONTO CHANCE POPS LONG ENOUGH. BUT
FUTURE SHIFTS WILL HAVE TO RE-EXAMINE THAT.
WITH COLDER SIR FILTERING IN THURSDAY NIGHT...EXPECT PRECIP WILL MIX
WITH...OR CHANGE TO SNOW ACROSS ALL...BUT THE SOUTHERN COALFIELDS.
THE AIRMASS WILL BE QUITE COLD FRO THIS TIME OF YEAR. BUT EXPECT
THE LOW-LEVEL TEMPS TO WARM ENOUGH FRIDAY AND SATURDAY,,,CAUSING THE
PRECIP TO CHANGE BACK TO RAIN.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ROLLER COASTER RIDE IN THE TEMP DEPARTMENT TO CONTINUE THRU THE
EXTENDED PERIODS. SURFACE HIGH AND A VERY DRY AIRMASS WILL ALLOW
FOR IDEAL RADIATIONAL COOLING SATURDAY NIGHT WITH MANY PLACES
DIPPING INTO THE TEENS. TRIED TO HIT THE TYPICAL COLD SPOTS HARD
WHILE KEEPING AREAS ALONG BIG RIVERS A FEW DEGREES HIGHER THAN
GUIDANCE SUGGESTS. A NICE REBOUND WILL BE REALIZED ON SUNDAY AMID WAA
ALOFT ON STRENGTHENING SW FLOW. A FAST MOVING COLD FRONT WILL
SLIDE THRU SUNDAY NIGHT WITH A CHANCE FOR SHOWERS. A WAVE MAY
DEVELOP IN THE TN VALLEY ON MONDAY WHICH WOULD KEEP THE RAIN
THREAT GOING ACROSS SW VA AND SE WV. TEMPS WILL COME BACK DOWN
BEHIND THE FRONT AS NW FLOW ALOFT BECOMES ESTABLISHED BEHIND A
CLIPPER SYSTEM EARLY TUESDAY...WITH A SMALL CHANCE FOR A SHOWER
AND SNOW SHOWER FOR THE N MOUNTAINS. UPPER HEIGHTS WILL QUICKLY
REBOUND MIDWEEK WITH DECENT WAA CRANKING ONCE AGAIN...AHEAD OF THE
NEXT FRONT. AS A RESULT...TEMPS SHOULD SPIKE INTO THE 70S ONCE
AGAIN LONG ABOUT WEDNESDAY.
&&
.AVIATION /05Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS CURRENTLY IN PLACE. PRECIPITATION MOVING INTO SW
OHIO. THIS PRECIP WILL CONTINUE EXPANDING NE ALONG A BOUNDARY THAT
WILL EVENTUALLY SINK SOUTHWEST AS A COLD FRONT DURING THE DAYLIGHT
HOURS. HAVE THUNDER POSSIBLE RIGHT ALONG THE FRONT...WITH MVFR IN
RAIN FOR SEVERAL HOURS BEHIND THE FRONT. WINDS WILL INCREASE OUT
OF THE SOUTH AHEAD OF THE FRONT...SWITCHING TO GUSTY NW BEHIND THE
FRONT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF RESTRICTIONS IN CLOUDS AND
PRECIPITATION ON THURSDAY 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 03/26/15
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
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 L L L L L L L L 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 06Z FRIDAY...
IFR POSSIBLE IN CIGS BEHIND THE COLD FRONT THU NIGHT IN THE
MOUNTAINS. IFR ALSO POSSIBLE LATE THURSDAY NIGHT INTO FRIDAY
ACROSS NRN WV AND DOWN THROUGH THE MOUNTAINS IN MIXED RAIN AND
SNOW SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/TRM/30
NEAR TERM...RPY
SHORT TERM...JSH
LONG TERM...30
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1152 PM CDT WED MAR 25 2015
.DISCUSSION...
UPDATED FOR 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 923 PM CDT WED MAR 25 2015/
UPDATE...
UPDATED TO RAISE POPS FOR REMAINDER OF THIS EVENING FROM PORTIONS
OF NORTHEAST AR INTO THE MO BOOTHEEL AS WIDESPREAD SHOWERS AND
THUNDERSTORMS ARE PUSHING INTO THIS AREA.
JCL
&&
.UPDATE... /ISSUED 739 PM CDT WED MAR 25 2015/
UPDATED FOR SEVERE THUNDERSTORM WATCH THAT INCLUDES PORTIONS OF
NORTHEAST AR...THE MO BOOTHEEL...AND PORTIONS OF NORTHWEST TN
UNTIL 2 AM CDT THU. THE MAIN THREATS WILL BE DAMAGING WINDS AND
LARGE HAIL. UPDATED ZONE FORECASTS AND GRIDS ALREADY SENT. ALSO
UPDATED THE HAZARDOUS WEATHER OUTLOOK TO EXPAND THE SLIGHT RISK
OF SEVERE THUNDERSTORMS EASTWARD.
JCL
&&
.DISCUSSION... /ISSUED 328 PM CDT WED MAR 25 2015/
CURRENTLY...A 1007 MB LOW PRESSURE SYSTEM IS LOCATED OVER THE RED
RIVER VALLEY WITH A WARM FRONT EXTENDING EAST INTO THE NORTHERN
PART OF THE MIDSOUTH. DEWPOINTS HAVE RISEN INTO THE UPPER 50S AND
LOWER 60S JUST SOUTH OF THE BOUNDARY WITH SBCAPES OF 1000-1500
J/KG. TEMPS ARE IN THE 70S WITH VARIABLY CLOUDY SKIES ACROSS THE
FORECAST AREA. SOUTH WINDS ARE BLOWING AT 10 TO 15 MPH WITH SOME
HIGHER GUSTS.
THIS EVENING INTO TONIGHT...THE LATEST HRRR INDICATES THAT
ISOLATED STORMS MAY DEVELOP ALONG THE WARM FRONT OVER THE NEXT
COUPLE OF HOURS. THESE MAKES SENSE GIVEN THE LACK OF CAP ACROSS
THE AREA...DECENT HEATING AND MODERATE INSTABILITY. ANY STORMS
THAT DO FORM WILL LIFT NORTH OF THE AREA BY EARLY EVENING AND
SHOULD REMAIN SUB SEVERE. THE EARLY EVENING SHOULD BE QUIET AND
MILD. AS THE EVENING PROGRESSES LOW PRESSURE WILL TRACK INTO
NORTHERN ARKANSAS WITH THUNDERSTORMS PUSHING INTO AND DEVELOPING
ACROSS SOUTHERN MISSOURI AND NORTHERN ARKANSAS. BY LATE EVENING
EXPECT CONVECTIVE SEGMENTS TO REACH NORTHEAST ARKANSAS. AT THIS
POINT THE INSTABILITY WILL BE WEAKENING BUT THERE SHOULD BE A
SEVERE THREAT WINDOW OF A FEW HOURS ACROSS NORTHEAST
ARKANSAS...THE MISSOURI BOOTHEEL AND EXTREME NORTHWEST TENNESSEE.
BY 03Z THERE IS STILL A FEW HUNDRED J/KG OF SBCAPE AND MODERATELY
STEEP LAPSE RATES SUFFICIENT WHEN COMBINED WITH THE SHEAR TO
SUPPORT THE CONTINUATION OF THE SEVERE THREAT UNTIL 06-07Z.
DAMAGING WINDS WILL BE THE MAIN THREAT WITH LARGE HAIL A SECONDARY
THREAT. AS THE COLD FRONT PUSHES IN SHOWER AND A THUNDERSTORM
CHANCES WILL INCREASE LATER TONIGHT ACROSS THE REST OF THE
MIDSOUTH. BY 12Z THU THE FRONT WILL BE LOCATED FROM PARIS TN TO
MEMPHIS TO THE ARKLATEX WITH MOST OF THE PRECIP POST FRONTAL BY
THAT POINT. TEMPS WILL BE DROPPING BEHIND THE FRONT ACROSS THE NW
HALF BRINGING AND ABRUPT END TO THE MILD WEATHER.
THURSDAY...COLD FRONT WILL PUSH THROUGH THE REMAINDER OF THE AREA
WITH SHOWERS AND A FEW THUNDERSTORMS MAINLY EAST OF THE
MISSISSIPPI RIVER. MANY PLACES WILL HAVE MORNING HIGHS WITH
FALLING OR STEADY TEMPS AS STRONG COLD AIR ADVECTION FOLLOWS THE
FRONT. THE SUN MAY PEEK OUT ACROSS NE AR BY LATE IN THE DAY AS THE
FRONT PUSHES EAST.
THURSDAY NIGHT THROUGH SATURDAY NIGHT...LARGE UPPER TROF OVER THE
EASTERN U.S. DURING THIS PERIOD WITH COOL NW FLOW ACROSS THE
MIDSOUTH. EXPECT WELL BELOW NORMAL TEMPERATURES...10 TO 15
DEGREES BELOW NORMAL...DURING THIS PERIOD. A COUPLE OF
DISTURBANCES MOVING THROUGH IN THE NW FLOW COULD PRODUCE PERIODS
OF LIGHT PRECIP BOTH FRIDAY AND SATURDAY. COULD EVEN BE A FEW SNOW
FLAKES ACROSS THE NORTHERN TIER SATURDAY MORNING THOUGH NOTHING
SIGNIFICANT EXPECTED AT THIS TIME. AS FAR AS THE POTENTIAL FOR
FREEZING TEMPS IS CONCERNED...LOOKS LIKE THE BEST CHANCES WILL BE
NORTH OF A JONESBORO AR TO SAVANNAH TN LINE SATURDAY MORNING AND
EAST OF A DYERSBURG TN TO FULTON MS LINE SUNDAY MORNING. SINCE WE
WILL NEED SOME CLEARING TO SEE SUBFREEZING TEMPS THESE
DISTURBANCES MOVING THROUGH THE FLOW MAKE FOR A DIFFICULT TEMP
FORECAST. STAY TUNED.
SUNDAY...LOOKING DRY AND MILDER AS THE UPPER TROF EXITS AND
SOUTHERLY WINDS DEVELOP. TEMPS BACK IN THE 60S.
SUNDAY NIGHT THROUGH WEDNESDAY...A COLD FRONT PROJECTED TO MOVE
THROUGH SUNDAY NIGHT WITH CHANCES FOR RAIN. THE MEDIUM RANGE
MODELS PUSH THE FRONT TO THE SOUTH WITH ONLY SMALL POPS EARLY
NEXT WEEK AND TEMPS BACK TO NORMAL. LOOKING MORE WET BY MIDWEEK AS
A MORE SIGNIFICANT SYSTEM MAY MOVE OUT OF THE MIDDLE OF THE
COUNTRY AND INTO THE MIDSOUTH.
SJM
&&
.AVIATION...
06Z TAF CYCLE
VFR AHEAD OF APPROACHING COLD FRONT. HOWEVER SHOWERS AND SOME
EMBEDDED STORMS WILL BRING MVFR WEATHER. BEST THREAT FOR STORMS ON
STATION WILL BE AT JBR...OTHERWISE VCTS AT MKL. BEHIND THE FRONT
PRECIPITATION WILL BE A LIGHT STEADY RAIN WITH MVFR AND IFR CIGS.
IMPROVING WEATHER IS STILL EXPECTED LATE. SOUTH WINDS AT 6-12 KTS
WILL VEER NORTH AND BECOME GUSTY. WINDS WILL DIMINISH LATE.
JAB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
401 AM CDT THU MAR 26 2015
.DISCUSSION...
AT 08Z SFC ANALYSIS SHOWS THE COLD FRONT STRETCHING FROM THE
ARKLATEX SW TO C TX AND NW HILL COUNTRY. A THIN LINE OF SHOWERS
HAS DEVELOPED ALONG AND JUST AHEAD OF THE FRONT. LLJ AT 850MB
STRETCHES FROM THE LOWER TX COAST NE THROUGH E TX AND TOWARDS THE
MISS RIVER VALLEY. WATER VAPOR AND 500MB ANALYSIS SHOW TROUGH AXIS
STRETCHING FROM THE N GREAT LAKES THROUGH THE PLAINS. POLAR JET
STRETCHES FROM THE S PLAINS NE TOWARDS THE GREAT LAKES WITH RIGHT
ENTRANCE REGION OVER OK MOVING EAST TOWARDS ARK. ANOTHER JET
STREAK WAS FOUND OVER THE N ROCKIES WHICH SHOULD FURTHER DEEPEN
THE TROUGH WITH UPPER LEVEL RIDGING OVER THE PAC COAST.
LATEST RAP/HRRR/3KM TXTECH WRF/4 KM WRF ARW ALL HAVE A PRETTY
GOOD HANDLE ON COLD FRONTAL PASSAGE ACROSS SE TX. LATEST 07Z HRRR
HAS INITIALIZED WELL AND BASED THE FIRST DAY FORECAST ON A BLEND
OF THESE TRENDS WITH THE RAP AND 3KM TX TECH WRF. FRONT SHOULD
REACH KCLL/KUTS 10-11Z...KIAH/KSGR/KHOU AROUND 13Z AND THEN OFF
THE COAST 15-16Z. MODELS DO SUPPORT CONVECTION INCREASING IN
COVERAGE MAINLY SOUTH OF HOUSTON AND ALONG THE COAST WHERE THE
FRONT INTERACTS WITH HIGHER MOISTURE. FORECAST WILL KEEP HIGHER
POPS FOR THE COASTAL AREAS AND OFFSHORE THROUGH 18Z. RAIN CHANCES
CLEAR OUT QUICKLY FROM 15-18Z INLAND. ANY THUNDERSTORM ACTIVITY
MAY BECOME STRONG BUT NOT LIKELY SEVERE DUE TO CAPPING AND LIMITED
INSTABILITY. THE 00Z CRP SOUNDING SHOWS A PRETTY GOOD CAP AT
800-750MB.
TEMP FORECAST WILL BE A CHALLENGE BECAUSE OF STRONG COLD
ADVECTION BEHIND THE FRONT. TEMPS ARE IN THE LOW/MID 60S THIS
MORNING AND MAY INCREASE A FEW DEGREES AHEAD OF THE FRONT MAINLY
ALONG THE COAST. TEMPS MAY DROP INTO THE 50S BEHIND THE FRONT BUT
AS CONVECTION/CLOUD COVER CLEARS...MAY GET SOME SLIGHT HEATING IN
THE AFTERNOON TO OFF SET COLD ADVECTION. SHORT RANGE MODELS KEEP
TEMPS IN THE 60S WHICH LOOKS REASONABLE.
FRI MORNING SHOULD BE A COOL START TO THE DAY WITH MIN TEMPS BACK
INTO THE 40S BUT MAX TEMPS SHOULD TOP OUT IN THE 70S. TEMPS
INCREASE OVER THE WEEKEND WITH WEAK UPPER LEVEL RIDGING OVER TX.
THE GFS/ECMWF DIVERGE IN THEIR SOLUTIONS OVER THE WEEKEND AND INTO
NEXT WEEK. WHILE THE MODELS THEMSELVES HAVE HAD RUN TO RUN
CONSISTENCY...THERE HAS NOT BEEN ANY CONSISTENCY WITH EACH OTHER.
THE PROBLEM SEEMS TO BE HOW EACH MODEL IS HANDLING A TROUGH THAT
PUSHES INTO THE PACIFIC COAST LATE FRI INTO SAT. THE ECMWF CUTS
OFF SOME VORTICITY FROM THIS TROUGH AND HAS IT RETROGRADE BACK
INTO THE PACIFIC WITH THE MAIN WAVE MOVING ACROSS THE PAC NW AND
INTO THE PLAINS BY SUNDAY. THE GFS DOES SIMILARLY WITH THE MAIN
WAVE BUT HAS A MORE COHERENT CLOSED OFF UPPER LOW OVER
CALIFORNIA/BAJA LATE SUNDAY. THIS SYSTEM THEN MOVES ACROSS THE S
ROCKIES INTO TX ON TUE. THE ECMWF HAS A MUCH WEAKER SYSTEM AND HAS
A STALLED FRONT ACROSS THE AREA. THIS MAKES THE FORECAST
CHALLENGING BECAUSE IF THE ECMWF VERIFIES THERE WILL BE LITTLE
WEATHER IMPACT. IF THE GFS IS CORRECT THEN THE TROUGH SWINGS OVER
SE TX WITH NEG TILT AND VERY FAVORABLE FOR HEAVY RAINFALL/SEVERE
WEATHER. FOR WHAT IT IS WORTH THE CANADIAN MODEL MIGHT BE A
COMPROMISE BETWEEN THE GFS/ECMWF BUT PERHAPS SUPPORTING THE ECMWF
A BIT MORE. FORECAST WILL KEEP 30/40 POPS AND MAX TEMPS WILL BE A
COUPLE DEGREES COOLER DUE TO POSSIBLE RAIN CHANCES AND CLOUD
COVER. THE SYSTEM CLEARS OUT EARLY NEXT WED WITH NO REAL CHANGE IN
AIRMASS. TEMPS NEXT WEEK COULD BE A GOOD 5-8 DEGREES ABOVE NORMAL.
39
&&
.MARINE...
A STRONG COLD FRONT WILL MOVE OFF THE COAST DURING THE MID AND
LATE MORNING. WINDS BEHIND THE FRONT ARE EXPECTED TO STRENGTHEN TO
ADVISORY LEVELS DURING THE EARLY AFTERNOON AND THEN PERSIST
THROUGH MOST OF THE EVENING. STRONGER WIND SPEEDS WILL LINGER OVER
THE OFFSHORE WATERS AFTER MIDNIGHT BEFORE DECREASING TOWARD
SUNRISE. HIGH PRESSURE WILL THEN BUILD INTO THE AREA ON FRIDAY.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 65 45 74 51 78 / 20 0 0 0 0
HOUSTON (IAH) 67 49 75 54 79 / 50 0 0 0 0
GALVESTON (GLS) 68 54 70 60 73 / 60 0 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM CDT FRIDAY
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 AM CDT FRIDAY
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...39
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
449 AM EDT THU MAR 26 2015
.SYNOPSIS...
A COLD FRONT TRAILED FROM THE GREAT LAKES TO A LOW OVER THE
SOUTHERN PLAINS EARLY THIS MORNING. THIS LOW WILL TRACK NORTHEAST
AND WILL PUSH A STRONG COLD FRONT THROUGH THE AREA TONIGHT. MUCH
COLDER AIR WILL BE MOVING IN BEHIND THE COLD FRONT FOR THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 430 AM EDT THURSDAY...
PERSISTENT WEDGE REMAINED IN PLACE EARLY THIS MORNING. BAND OF
SHOWERS AND ISOLATED THUNDERSTORMS TRACKING TOWARD DANVILLE AND
SOUTHEAST COUNTIES OF THE FORECAST AREA WILL BE ELEVATED OVER A
SHALLOW BUT STRONG INVERSION. JUST ABOVE THE INVERSION
LEVEL...STRATUS HAD FORMED IN ALL BUT THE FAR WESTERN COUNTY
WARNING AREA. HIGHER ELEVATIONS WERE IN THE CLOUDS WITH DRIZZLE
AND FOG REPORTED.
LATEST HRRR AND WRF RUNS HAD BEST PROBABILITY OF SHOWERS THIS
MORNING IN SOUTHEAST HALF OF THE FORECAST AREA...ESPECIALLY EAST
OF DANVILLE AND LYNCHBURG. BUFKIT SOUNDINGS SHOWED THE WEDGE
BREAKING IN MOST LOCATIONS BY NOON WITH THE STRATUS AND FOG
LIFTING AND WINDS COMING AROUND TO THE SOUTHWEST.
THIS AFTERNOON WHEN THE FORECAST AREA IS OUT OF THE WEDGE AND INTO
THE WARM SECTOR AHEAD OF THE FRONT EXPECTING ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL BE ABOUT 10
TO 15 DEGREES ABOVE NORMAL...BUT EVEN WITH THE WARMING...ONLY
MARGINAL CAPE IS EXPECTED DUE A WARM LAYER AROUND 700 MB THIS
AFTERNOON.
AT 4AM THE COLD FRONT EXTENDED FROM PITTSBURGH TO LITTLE ROCK. LOW
PRESSURE WILL MOVE ALONG THE BOUNDARY TONIGHT. A STRONG UPPER
TROF BEGINS TO DIG IN THE CENTRAL UNITED STATES TONIGHT. SHOWERS
WILL BE WIDESPREAD ALONG AND BEHIND THE FRONT. KEPT THE CHANCE OF
THUNDERSTORMS IN FOR THIS EVENING. 00Z LOCAL WRF WAS AN HOUR OF
TWO FASTER WITH THE FRONTAL PASSAGE THAN THE NAM AND GFS. AT THIS
TIME EXPECT THE FRONT TO REACH THE FAR WESTERN COUNTY WARNING AREA
AROUND 00Z/8PM AND EXIT THE EASTERN COUNTIES AROUND 05Z/1AM.
TEMPERATURES WILL DROP QUICKLY BEHIND THE FRONT TONIGHT. AIR MASS
WILL BE COLD ENOUGH TO SUPPORT SNOW IN THE HIGHEST ELEVATIONS WEST
OF THE BLUE RIDGE BY EARLY FRIDAY MORNING. THE STRONG COLD AIR
ADVECTION COMBINED WITH PRESSURE RISES OF 5 TO 10MB/6HRS WILL
RESULT IN GUSTY WINDS TONIGHT. BUFKIT SOUNDINGS SUGGESTED
OCCASIONAL GUST OF 25 TO 35 MPH.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
AS OF 345 AM EDT THURSDAY...
MODEL GENERATION OF WAVES ALONG THE COLD FRONT HAVE SLOWED ITS
PROJECTED PASSAGE ACROSS THE REGION. AND WHILE THE FRONT WILL BE
CLEAR OF US TO THE EAST BY FRIDAY...THE FRONTAL WAVES BEING DRIVEN
BY UPPER LEVEL SHORT WAVE ENERGY WILL KEEP RESIDUAL PRECIPITATION
ACROSS THE EAST FRIDAY MORNING. AT THE SAME TIME NORTHWEST WINDS
WILL BE GENERATING UPSLOPE PRECIPITATION WEST OF THE BLUE RIDGE AS
MUCH COLDER COLDER AIR MOVES IN. THE UPSLOPE PRECIPITATION WILL BE
RAIN FOR MOST LOCATIONS WEST OF THE RIDGE BUT THE HIGHER ELEVATIONS
OF THE FAR WESTERN SLOPES WILL SEE SNOW SHOWERS. GIVEN THE STRENGTH
OF THE SUN THIS TIME OF YEAR AND WARM ANTECEDENT CONDITIONS NO
ACCUMULATION IS EXPECTED DURING THE DAYTIME ON FRIDAY. BY FRIDAY
NIGHT THE HEART OF THE VERY COLD AIR WILL SURGE INTO THE
REGION...ALLOWING FOR UPSLOPE PRECIPITATION TO CHANGE TO SNOW FOR
ALL LOCATIONS WEST OF THE RIDGE. WITH NO SUN TO COMPETE WITH...SOME
ACCUMULATION IS POSSIBLE FRIDAY NIGHT MAINLY FOR THE FAR WESTERN
SLOPES WHERE AMOUNTS WILL GENERALLY BE AN INCH OR LESS. HIGH PRESSURE
WILL THEN BUILD IN FOR THE WEEKEND...BRINGING AN END TO THE SNOW
SHOWERS SATURDAY MORNING WITH FAIR WEATHER ON TAP THROUGH SUNDAY.
TEMPERATURES WILL BE RUNNING 10 TO 15 DEGREES BELOW NORMAL THROUGH
THE PERIOD WITH SATURDAY BEING THE COLDEST DAY OF THIS STRETCH. LOWS
SATURDAY MORNING WILL BOTTOM OUT GENERALLY IN THE TEENS WEST OF THE
RIDGE TO MIDDLE 20S EAST. WINDS WILL ALSO BE BLUSTERY AS THE COLDER
AIR MOVES IN FRIDAY AND FRIDAY NIGHT...PRODUCING WIND CHILL VALUES
SATURDAY MORNING OF ZERO TO 10 ABOVE WEST TO THE LOWER AND MIDDLE 20S
EAST. HIGHS SATURDAY WILL ONLY BE IN THE LOW TO MID 30S WEST AND IN
THE MID TO UPPER 40S EAST. THANKFULLY TEMPERATURES WILL START TO
REBOUND AS WE CLOSE OUT THE WEEKEND WITH THE COLD AREA OF HIGH
PRESSURE SINKING TO OUR SOUTHEAST...ALLOWING OUR WINDS TO COME
AROUND TO A SOUTHWESTERLY DIRECTION AND BRING WARMER AIR BACK INTO
THE REGION.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 400 PM EDT WEDNESDAY...
NORTHWEST FLOW PREVAILS THROUGH MONDAY WITH AN ALBERTA CLIPPER
PROGGED TO TRACK ACROSS THE REGION SUNDAY NIGHT TO MONDAY. THE GFS
IS FASTER AND STRONGER WITH THIS SYSTEM THAN THE ECMWF...BUT GIVEN
THE PATTERN IN PLACE AT THAT POINT...THE GFS FORECAST SEEMS MORE
REASONABLE. POPS ARE QUESTIONABLE WITH THIS SYSTEM...SO HAVE JUST
INDICATED LOW CHC POPS IN THE WEST FOR NOW UNTIL BETTER CONSENSUS IS
OBTAINED FROM THE MODELS ON THIS SYSTEM. BEYOND THAT...THE UPPER
FLOW BECOMES MORE ZONAL AND THE FOCUS WILL BE ON A HIGHLY
KINEMATIC...PACIFIC BASED SYSTEM IN THE SOUTHERN STREAM EXPECTED TO
REACH THE CWA AT THE END OF THE FORECAST PERIOD. THIS COULD BE A
SEVERE WEATHER SYSTEM FOR THE SOUTHERN PLAINS TO THE SOUTHEAST
STATES...BUT MORE QUESTIONABLE FOR OUR AREA. YIELDED TOWARD THE
SUPERBLEND FOR POPS IN THE LAST TWO PERIODS TO BETTER AGREE WITH
NEIGHBORS. HOWEVER...TIMING OF THE ARRIVAL OF WARM ADVECTION
PRECIPITATION ASSOCIATED WITH THIS SYSTEM REMAINS HIGHLY
QUESTIONABLE AT THIS POINT. THE ZONAL FLOW WILL YIELD TO NEAR NORMAL
TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
AS OF 150 AM EDT THURSDAY...
RADAR SHOWED SCATTERED LIGHT RAIN DEVELOPING OVER NORTH CAROLINA
AND MOVING NORTH INTO VIRGINIA EARLY THIS MORNING. BUFKIT FORECAST
SHOWED CEILINGS LOWERING TO IFR EARLY THIS MORNING UNDER A
SHALLOW BUT STRONG INVERSION. HAVE ADDED LLWS INTO THE KBLF AND
KLWB TAFS FOR THIS MORNING.
PERSISTENT WEDGE AND INVERSION WILL BREAK THIS MORNING. MEDIUM
CONFIDENCE THAT CEILINGS WILL IMPROVE BACK TO MVFR WITH WINDS
COMING AROUND TO THE SOUTHWEST BY 17Z/NOON.
HIGH CONFIDENCE THAT A STRONG COLD FRONT WILL CROSS THROUGH THE
REGION JUST AFTER 00Z/7PM AT KLWB AND KBLF. THE FRONT IS EXPECTED
TO REACH KLYH AROUND 04Z/MIDNIGHT AND KDAN AROUND 05Z/1AM. EXPECT
A BAND OF MODERATE TO HEAVY SHOWERS ALONG AND JUST BEHIND THE
FRONT. VISIBILITY MAY DROP TO MVFR LEVELS IN THE HEAVIER RAIN.
WINDS WILL BECOME NORTHWEST BEHIND THE FRONT WITH GUSTS AT 20 TO
30 KNOTS.
SHOWERS AND GUSTY WINDS WILL CONTINUE THROUGH FRIDAY AS MUCH
COLDER AIR SURGES INTO THE REGION. SNOW SHOWERS ARE LIKELY WITH
MVFR CEILINGS AND VISIBILITIES IN THE WESTERN UPSLOPE AREAS OF THE
MOUNTAINS FRIDAY AND FRIDAY NIGHT. WINDS WILL DIMINISH SATURDAY
AND SATURDAY NIGHT WITH VFR CONDITIONS AS HIGH PRESSURE BUILDS
INTO THE AREA. VFR WEATHER IS EXPECTED SUNDAY AND MONDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/RCS
SHORT TERM...MBS
LONG TERM...RAB
AVIATION...AMS
AREA FORECAST DISCUSSION
NWS ALBANY NY
835 AM EDT THU MAR 26 2015
.SYNOPSIS...
AFTER A BRIEF BREAK IN THE PRECIPITATION EARLY TODAY...A
LOW PRESSURE SYSTEM AND ITS COLD FRONT WILL ALLOW FOR WIDESPREAD
RAIN TO DEVELOP BY THIS AFTERNOON. AS THE COLD FRONT MOVES SOUTH OF
THE REGION...THE RAIN WILL MIX WITH THEN CHANGE TO SNOW OVER THE
HIGHER BY THIS EVENING INTO TONIGHT. SOME LIGHT ACCUMULATING SNOW
WILL BE POSSIBLE FOR MOST HIGHER TERRAIN AREAS TONIGHT. COLDER
WEATHER WILL ONCE AGAIN BE IN PLACE FOR FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 835 AM EDT...REGIONAL RADAR SHOWS A BREAK IN THE
PRECIPITATION CONTINUES OVER THE FORECAST AREA THIS MORNING.
DESPITE THE LACK OF PRECIP...EXTENSIVE LOW CLOUDS ARE IN
PLACE...ALONG WITH AREAS OF FOG. WITH THE MOIST AREA AND TEMPS
JUST ABOVE FREEZING OVER A SNOWPACK...THE FOG IS LOCALLY DENSE IN
SOME LOCATIONS. A FEW LOCATIONS ABOVE THE CLOUD COVER...SUCH AS IN
THE SRN GREENS...CATSKILLS AND HELDERBERGS...ARE ACTUALLY SEEING
SOME SUNSHINE...BUT THIS IS GENERALLY AT ELEVATIONS ABOVE 1000
FEET. THESE BREAKS WILL END BY LATER THIS MORNING...AS ADDITIONAL
CLOUD COVER MOVES INTO THE REGION FROM THE SOUTH AND WEST THIS
MORNING.
A STORM SYSTEM EXTENDS FROM THE MISSISSIPPI VALLEY TOWARDS THE
OHIO VALLEY AND MID ATLANTIC STATES...AND THIS SYSTEM WILL BE
IMPACTING OUR WEATHER TODAY. THE LATEST 3KM HRRR SHOWS THAT IT
SHOULD REMAIN DRY THROUGH THE LATE MORNING HOURS...BUT RAIN WILL
RAPIDLY ADVANCE INTO THE AREA FROM CNY...AS THE FRONTAL BOUNDARY
LIFTS TOWARDS OUR REGION. DUE TO THE BROAD SW FLOW IN PLACE...THE
RAIN WILL INITIALLY BE IMPACTING AREAS NORTH AND WEST OF THE
CAPITAL REGION. RAINFALL WILL BE STEADY...AND MAY BE LOCALLY
MODERATE AT TIMES.
THROUGH THE AFTN...STEADY RAIN WILL EXPAND ACROSS THE ENTIRE
REGION...AS A FRONTAL BOUNDARY GRADUALLY WORKS FROM WEST TO EAST
TOWARDS THE AREA. THIS FRONT WILL BE SLOWED DUE TO A WAVE OF LOW
PRESSURE MOVING UP ALONG THE BOUNDARY. TEMPS WILL START FALLING
ACROSS NORTHWESTERN AREAS BY LATE THIS AFTN...BUT SHOULD BE MILDER
COMPARED TO PREVIOUS DAYS ACROSS FAR SOUTHERN AREAS...WHERE TEMPS
MAY GET CLOSE TO 50. ELSEWHERE...EXPECT TEMPS ONLY IN THE UPPER
30S TO MID 40S.
BY EARLY THIS EVENING...THE FRONT WILL BE WORKING ACROSS OUR
AREA...AND THE HEAVIEST PRECIP WILL BE OCCURRING JUST ALONG/AHEAD
OF THIS BOUNDARY. WITH SOME ELEVATED INSTABILITY IN PLACE
/SHOWALTER VALUES AT OR SLIGHTLY BELOW ZERO/ THERE MAY BE A RUMBLE
OF THUNDER ACROSS ULSTER....DUTCHESS...OR LITCHFIELD COUNTIES. AT
THE SAME TIME...RAIN WILL BE STARTING TO TRANSITION TO SNOW ACROSS
THE WESTERN ADIRONDACKS...AS COLDER AIR POURS INTO THE REGION
BEHIND THE FRONTAL BOUNDARY FROM CANADA.
ABOUT A HALF TO THREE QUARTER OF AN INCH OF RAIN IS POSSIBLE
THROUGH THIS EVENT TODAY. PLEASE SEE OUR HYDRO DISCUSSION ON HOW
WE EXPECT TODAY/S RAINFALL TO IMPACT OUR HYDRO SERVICE AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
TEMPERATURES WILL GRADUALLY COOL TONIGHT FROM NORTHWEST TO
SOUTHEAST ACROSS THE REGION...WHICH COULD ALLOW FOR A RAIN/SNOW
MIX EVEN IN THE VALLEYS LATE TONIGHT INTO EARLY FRIDAY MORNING.
THE SURFACE LOW IS FORECAST TO PULL AWAY FROM THE REGION ON
FRIDAY...HOWEVER AN UPPER LEVEL TROUGH IS FORECAST TO GRADUALLY
TRACK FROM THE GREAT LAKES INTO THE NORTHEAST FRIDAY INTO EARLY
SATURDAY. THIS WILL LEAD TO ISOLATED TO SCATTERED RAIN/SNOW
SHOWERS WITH MAINLY CLOUDY SKIES AND TEMPS BELOW NORMAL.
EXPECT LOWS TONIGHT TO RANGE FROM THE MID 20S NORTHWEST TO THE
UPPER 30S SOUTHEAST WITH HIGHS ON FRIDAY IN THE MID 30S TO UPPER
40S. LOWS FRIDAY NIGHT ARE EXPECTED TO BE IN THE SINGLE DIGITS
NORTHWEST TO MID 20S SOUTHEAST.
ON SATURDAY THE UPPER LEVEL TROUGH AXIS AND ASSOCIATED VORT MAX
SWINGS THROUGH THE FA. THIS WILL RESULT IN MAINLY WIDELY SCATTERED
TO SCATTERED SNOW SHOWERS. HIGHS ON SATURDAY ARE EXPECTED TO BE IN THE
MID 20S TO MID 30S. SATURDAY NIGHT IS EXPECTED TO BE CLEAR AND
COLD AS A RIDGE OF HIGH PRESSURE BUILDS SOUTHEAST FROM THE CENTRAL
GREAT LAKES TO THE TENNESSEE VALLEY. LOWS SATURDAY NIGHT ARE
EXPECTED TO RANGE FROM THE SINGLE DIGITS NORTHWEST TO UPPER TEENS
SOUTHEAST.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE EXTENDED FORECAST FEATURES A FAIRLY PERSISTENT MEAN LONGWAVE
TROUGH OVER THE NORTHEAST AND SOUTHEASTERN CANADA WITH A FEW
DISTURBANCES IN THE W/NW FLOW BRINGING SOME RAIN AND SNOW SHOWERS TO
THE REGION.
SUNDAY...THE WEEKEND CLOSES WITH SFC HIGH PRESSURE RIDGING IN FROM
THE MID ATLANTIC REGION. THE UPPER LEVEL TROUGH MOVES OFFSHORE.
THERE WAS GOOD AGREEMENT WITH THE GFS/GEFS/ECMWF/WPC GUIDANCE HERE.
H850 TEMPS WILL BE A LITTLE BELOW NORMAL IN THE -4C TO -7C RANGE.
THE SUBSIDENCE FROM THE SFC ANTICYCLONE WILL PROVIDE PLENTY OF
SUNSHINE WITH TEMPS RUNNING ABOUT 5 TO 10 DEGREES BELOW NORMAL.
HIGHS WILL RANGE FROM THE U30S TO M40S IN THE VALLEYS...AND 30S OVER
THE MTNS.
SUNDAY NIGHT INTO MONDAY...A PROGRESSIVE UPPER LEVEL TROUGH
APPROACHES FROM THE ONTARIO...THE GREAT LAKES REGION...AND THE
MIDWEST SUNDAY NIGHT. CLOUDS INCREASE OVERNIGHT WITH THE CLIPPER
TYPE LOW TRACKING TOWARDS THE REGION. THE SYSTEMS COLD FRONT WILL
REACH THE ST LAWRENCE RIVER VALLEY TOWARDS DAYBREAK ON MONDAY.
INITIALLY WEAK ISENTROPIC LIFT AHEAD OF THE SYSTEM MAY KICK OFF SOME
SCT SNOW SHOWERS...ESPECIALLY FROM THE CAPITAL REGION NORTH AND
WEST. SOME LIGHT ACCUMS WILL BE POSSIBLE. SOME OF THE SNOW SHOWERS
MAY EVEN REACH THE HUDSON RIVER VALLEY EARLY ON. THE PCPN WILL
LIKELY TRANSITION TO A MIXTURE OF RAIN AND SNOW SHOWERS AS THE
BOUNDARY LAYER WARMS DUE TO S TO SW FLOW ALOFT. EXPECT SEASONABLE
AND BREEZY CONDITIONS. THE COLD FRONT WILL BE POISED TO MOVE
THROUGH TOWARDS THE LATE AFTERNOON. AFTER LOWS IN THE 20S TO AROUND
30F IN THE MID HUDSON VALLEY...EXPECT HIGHS TO REACH THE 40S TO L50S
IN THE VALLEYS...AND U30S TO L40S OVER THE HIGHER ELEVATIONS.
MONDAY NIGHT...THE COLD FRONT MOVES THROUGH WITH SCT SNOW SHOWERS
MAINLY NORTH AND WEST OF THE CAPITAL DISTRICT AND THE MID HUDSON
VALLEY. SOME W/NW UPSLOPE SNOW SHOWERS WILL LINGER ACROSS THE SRN
GREENS AND SRN DACKS. AGAIN...ANY ACCUMS LOOK VERY LIGHT. EXPECT
LOWS TO FALL BACK INTO THE 20S TO L30S IN THE COLD ADVECTION REGIME.
TUE-TUE NIGHT...ANOTHER CLIPPER LOW MAY DIVE S/SE ACROSS THE CNTRL
GREAT LAKES REGION...AND INTO PA LATE TUE PM INTO TUE NIGHT
ACCORDING TO THE ECMWF MISSING MOST OF THE FCST AREA. THE GFS WOULD
HAVE A SECONDARY COLD FRONT MOVING THROUGH WITH SOME ISOLD-SCT
UPSLOPE SNOW SHOWERS WITH HIGH PRESSURE BUILDING IN. WPC IS A
LITTLE CLOSER TO THE GFS. WE WENT MAINLY DRY TUESDAY INTO TUESDAY
NIGHT WITH COLD CONDITIONS FOR THE LAST DAY OF MARCH. THE GFS HAS
H850 TEMPS IN THE -9C TO -13C RANGE OVER THE FCST AREA. TEMPS WILL
RUN 5 OR MORE DEGREES BELOW NORMAL...AS HIGHS WILL BE IN THE 40S IN
THE VALLEYS...AND M30S TO AROUND 40 OVER THE HILLS AND MTNS.
OVERNIGHT LOWS WILL BE COLD IN THE 20S TO L30S WITH A FEW TEENS OVER
THE SRN DACK PARK.
WEDNESDAY...WEAK RIDGING ALOFT WILL START THE DAY...AND THEN ANOTHER
CLIPPER LIKE DISTURBANCE WILL APPROACH FROM THE GREAT LAKES REGION
LATE IN THE DAY. A SLIGHT OR LOW CHC OF RAIN/SNOW SHOWERS WAS KEPT
IN THE FCST PREDOMINANTLY WEST OF THE HUDSON RIVER VALLEY. TEMPS
WILL BE A LITTLE BELOW NORMAL TO START APRIL.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
A WARM FRONT WILL MOVE ACROSS ERN NY AND WRN NEW ENGLAND THIS
MORNING. A COLD FRONT WILL BECOME STATIONARY OVER EAST CENTRAL NY
AND NEW ENGLAND EARLY THIS AFTERNOON...AS LOW PRESSURE WILL MOVE
ALONG IT BRINGING PERIODS OF RAIN BACK INTO THE REGION. THE COLD
FRONT WILL SLOWLY MOVE S/SE ACROSS THE REGION LATE THURSDAY
AFTERNOON THROUGH THURSDAY NIGHT.
LOW STRATUS AND MIST/FOG HAS FORMED AT KGFL/KALB/KPSF/KPOU EARLY
THIS MORNING IN THE WARM ADVECTION ENVIRONMENT AHEAD OF THE WARM
FRONT. THE LOW STRATUS IS EXPECTED TO CONTINUE AT ALL THE
SITES...EXPECT WIDESPREAD IFR/LIFR CONDITIONS PRIOR TO 15Z. SOME
IMPROVEMENT TO IFR/HIGH MVFR IS POSSIBLE PRIOR TO ARRIVAL OF THE
RAINFALL AT 18Z. THE IMPROVEMENT WILL ONLY BE TEMPORARY AS THE
RAIN MOVES BACK IN PRODUCING WIDESPREAD IFR CONDITIONS AGAIN IN
TERMS OF CIGS AND VSBYS. THE MELTING SNOW WILL ALSO INCREASE THE
FOG POTENTIAL. THE CONDITIONS WILL CONTINUE AT IFR AND POSSIBLY
EVEN LIFR LEVELS AT KPSF AFTER 00Z/FRI.
THE PCPN MAY MIX WITH RAIN AND SNOW AS THE THE FRONT SAGS SOUTH
BTWN 03Z-05Z...ESPECIALLY AT KGFL/KPOU...BUT THE CIGS AND VSBYS
SHOULD IMPROVE MVFR LEVELS AT ALL THE SITES.
EXPECT MAINLY VARIABLE IN DIRECTION WINDS IN THE LATE MORNING
INTO THE EARLY AFTERNOON AT 7 KTS OR LESS. THE WINDS WILL SHIFT TO
THE NE TO NW AT 5-10 KTS IN THE LATE AFTERNOON INTO THE EARLY
EVENING.
OUTLOOK...
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE RA/SN.
FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE SHRA.
FRIDAY NIGHT-SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE SHSN.
SATURDAY-MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
FIRE WEATHER ISSUES ARE NOT ANTICIPATED OVER THE NEXT SEVERAL DAYS
WITH SNOW COVER IN PLACE ACROSS MUCH OF THE REGION...AND WET/
UNSETTLED WEATHER FORECAST INTO FRIDAY.
AFTER A BRIEF BREAK IN THE PRECIPITATION EARLY TODAY...A
LOW PRESSURE SYSTEM AND ITS COLD FRONT WILL ALLOW FOR WIDESPREAD
RAIN TO DEVELOP BY THIS AFTERNOON. AS THE COLD FRONT MOVES SOUTH OF
THE REGION...THE RAIN WILL MIX WITH THEN CHANGE TO SNOW OVER THE
HIGHER TERRAIN MAINLY NORTH AND WEST OF THE CAPITAL DISTRICT TODAY
INTO THIS EVENING. SOME LIGHT ACCUMULATING SNOW WILL BE POSSIBLE FOR
MOST HIGHER TERRAIN AREAS TONIGHT. COLDER WEATHER WILL ONCE AGAIN BE
IN PLACE FOR FRIDAY INTO THE WEEKEND.
&&
.HYDROLOGY...
WIDESPREAD HYDRO ISSUES ARE NOT EXPECTED THROUGH THE NEXT 5
DAYS...ALTHOUGH A FEW RIVER POINTS MAY GET CLOSE TO BANKFULL OVER
THE NEXT COUPLE DAY DUE TO RAINFALL AND SOME SNOWMELT. ALSO ISOLATED
ICE JAMS WILL BE POSSIBLE ACROSS THE SOUTHEAST HALF OF THE HYDRO
SERVICE AREA.
ON THURSDAY...MILDER AIR WITH DEWPOINTS CLIMBING INTO THE 40S
MAINLY SOUTH OF I-90... ALONG WITH RAINFALL IN THE HALF AN INCH TO
THREE QUARTERS OF AN INCH RANGE...WILL PRODUCE SOME MELTING OF
THE SNOW...AND POTENTIALLY ICE BREAKUP ON THE RIVERS.
THE LATEST MMEFS GUIDANCE INCLUDING THE NAEFS...GEFS...AND SREFS NOW
INDICATE NO RIVER POINTS FORECAST TO REACH FLOOD STAGE. THE LATEST
NERFC FORECASTS SHOW ABOUT 4 POINTS GETTING TO THE ALERT STAGE EAST
OF THE HUDSON RIVER VALLEY...BUT NO FLOODING AT THIS TIME.
CONFIDENCE CONTINUES TO BE LOW FOR THE POTENTIAL OF WIDESPREAD
FLOODING...SO NO WATCH HAS BEEN ISSUED AT THIS TIME.
THE MOST LIKELY TIME FRAME FOR ANY POTENTIAL PROBLEMS WOULD BE
THURSDAY EVENING FOR SMALL STREAMS...AND NOT UNTIL FRIDAY FOR THE
CRESTING OF THE BIGGER RIVERS. BY THAT TIME...TEMPERATURES ACROSS
THE ADIRONDACKS WILL BE AT OR BELOW FREEZING. NO SIGNIFICANT
PROBLEMS ARE EXPECTED ACROSS THE NORTHERN TIER OF THE HYDRO SERVICE
AREA...AS MUCH OF THE RAIN WILL SOAK OR BE ABSORBED INTO THE
SNOWFALL...AND THE RAIN WILL CHANGE TO SNOW LATE THURSDAY INTO
THURSDAY NIGHT.
THE POTENTIAL ALSO EXISTS FOR ISOLATED ICE JAMS THURSDAY INTO
FRIDAY...AS ICE BREAKS UP MAY OCCUR ON SOME RIVERS AND
STREAMS...PARTICULARLY FROM THE CAPITAL DISTRICT SOUTH AND EAST
WHERE ICE STILL EXISTS. THIS WILL BE MONITORED OVER THE NEXT COUPLE
OF DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/11/JPV
NEAR TERM...FRUGIS
SHORT TERM...11/JPV
LONG TERM...WASULA
AVIATION...WASULA
FIRE WEATHER...11
HYDROLOGY...11/JPV/WASULA
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
957 AM EDT THU MAR 26 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL WEAKEN AHEAD OF A STRONG COLD FRONT
APPROACHING TONIGHT AND SWEEPING THROUGH DURING FRIDAY. COLDER HIGH
PRESSURE WILL THEN BUILD FOR THE WEEKEND...SUPPORTING A POSSIBLE
FREEZE FOR SOME INLAND AREAS EARLY SUNDAY. HIGH PRESSURE THEN SHIFTS
SOUTH OF THE REGION MONDAY...BEFORE ANOTHER COLD FRONT MOVES
THROUGH LATE MONDAY OR EARLY TUESDAY. HIGH PRESSURE WILL THEN
PREVAIL INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE REGION WILL REMAIN SOLIDLY WITHIN THE WARM SECTOR TODAY AHEAD
OF AN APPROACHING COLD FRONT. EXTENSIVE LOW CLOUDS ARE BEGINNING
TO THIN AND BREAK UP PER LATEST SATELLITE TRENDS. THIS INCREASED
INSOLATION COUPLED WITH 850 HPA TEMPERATURES APPROACHING 12C WILL
SUPPORT HIGHS NEAR 80-82F MOST LOCATIONS AWAY FROM THE BEACHES
THIS AFTERNOON. CLOUDS WILL BEGIN TO THICKEN UP LATER THIS
AFTERNOON AS HIGH CLOUDS INCREASE AND A CUMULUS FIELD DEVELOPS...
WHICH WILL RETURN THE SKY CHARACTER BACK TO PARTLY SUNNY TO
MOSTLY CLOUDY.
THE RISK FOR SHOWER ACTIVITY LOOKS MINIMAL WITH MODIFIED OBSERVED
AND FORECAST SOUNDINGS SHOWING LITTLE IN THE WAY OF INSTABILITY.
THIS IS SUPPORTED BY THE LATEST RAP AND H3R RUNS. THE BEST RAIN
CHANCES WILL HOLD OFF UNTIL AFTER 6 PM AS A COLD FRONT AND
ASSOCIATED SHORTWAVE ENERGY DRAW CLOSER. COULD SEE AN ISOLATED
SHOWER DEVELOP ALONG THE RESULTANT SEA BREEZE ITSELF WHERE LOW-
LEVEL MOISTURE FLUX CONVERGENCE WILL BE LOCALLY MAXIMIZED... BUT
THE OVERALL RISK FOR THIS IS TOO SMALL TO JUSTIFY A MENTIONABLE
POP ATTM. WILL CONTINUE TO MONITOR CONVECTIVE TRENDS THROUGH THE
DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
TONIGHT...RAIN CHANCES INCREASE AS THE FRONT APPROACHES FROM THE
WEST AND LARGE SCALE LIFT/DEEP MOISTURE MOVE INTO THE AREA.
INSTABILITY APPEARS WEAK BUT CANNOT RULE OUT A FEW THUNDERSTORMS
GIVEN THE INCREASING LOW-LEVEL JET/DEEP LAYER SHEAR. GIVEN THE
WARM AND HUMID AIR MASS ADVECTING INTO THE AREA THERE MIGHT STILL
BE SOME SEA FOG NEAR THE COAST...ESPECIALLY UNTIL WINDS BECOME
MORE SOUTHWEST AFTER MIDNIGHT. TEMPS WILL LIKELY NOT DROP BELOW
60 DEGREES.
FRIDAY...A DEEPENING AND AMPLIFYING LONG WAVE TROUGH WILL PREVAIL
OVER THE EASTERN STATES...WITH SOME PHASING OF A SHORT WAVE OVER THE
LOWER MS VALLEY WITH ANOTHER AND STRONGER SHORT WAVE THAT DIVES FROM
THE MID MS VALLEY INTO THE TN VALLEY IN THE AFTERNOON. THIS
TRANSITION WILL CAUSE HEIGHTS ALOFT TO STEADILY FALL AND WILL SHOVE
A STRONG COLD FRONT INTO THE NW TIER DURING THE MID-LATE
MORNING...TOWARD OUR COASTAL CORRIDOR BY EARLY AFTERNOON...AND INTO
THE ATLANTIC THEREAFTER. LOW LEVEL CONVERGENCE WILL COMBINE WITH
LARGER SCALE FORCING FOR ASCENT DUE TO STRONG VERTICAL WIND FIELDS
THROUGHOUT THE TROPOSPHERE...MOST NOTABLY A 30-40 KT LOW LEVEL JET
AND A 130-150 UPPER JET. THESE DYNAMICS WILL HAVE CONSIDERABLE
MOISTURE TO WORK WITH...AS PWATS ARE AS MUCH AS 1-2 STANDARD
DEVIATIONS ABOVE NORMAL FOR LATE MARCH. THIS WILL RESULT IN AT
LEAST 60-70 POPS MAINLY IN THE FORM OF SHOWERS. HOWEVER...GIVEN 50-
60 KT OF BULK SHEAR AND SBCAPES THAT COULD BE AS GREAT AS 300-500
J/KG THERE CERTAINLY COULD BE A FEW RUMBLES OF THUNDER. RAIN CHANCES
WILL PEAK IN THE MORNING...THEN TAIL OFF FROM WEST TO EAST IN THE
AFTERNOON.
WARM ADVECTION IN ADVANCE OF THE COLD FRONT WILL ASSIST IN NEGATING
THE LACK OF INSOLATION...BUT FRIDAY WILL CERTAINLY BE NOTICEABLY
COOLER THAN IT WILL BE TODAY. IN FACT AS COLD ADVECTION ARRIVES IN
THE AFTERNOON THERE COULD ACTUALLY BE SOME SLOW FALL TO SOME OF OUR
TEMPS THE REST OF THE DAY.
FRIDAY NIGHT...ALTHOUGH THE DEEP MOISTURE WILL HAVE PULLED EAST WITH
THE COLD FRONT...THERE IS STILL SOME LINGERING LOW LEVEL MOISTURE
WITHIN THE FIRST COUPLE OF MILES OFF THE DECK. A POTENT SHORT WAVE
EMBEDDED WITHIN THE LONG WAVE TROUGH ALOFT WILL MOVE DIRECTLY
THROUGH THE CWFA AROUND 05-08Z. THIS WILL SUPPORT 20-30 POPS AND
MAINLY ACROSS THE CHARLESTON TRI-COUNTY REGION WHERE THE BEST
MOISTURE WILL REMAIN. ALTHOUGH COLDER AIR WILL BE FILTERING IN...AS
PER SOUNDING PROFILES IT LOOKS LIKE ONE OF THOSE EVENTS WHERE THE
COLD AIR IS TRYING TO CATCH UP TO THE DEPARTING MOISTURE AND IT WILL
ARRIVE TOO LATE TO PRODUCE ANYTHING OTHER THAN LIQUID. BUT DUE TO
THE STEEP MID LEVEL LAPSE RATES WHERE 500 MB TEMPS ARE NEAR MINUS
27C...THERE APPEARS TO BE A RISK FOR SOME GRAUPEL OR SOFT HAIL. 850
MB TEMPS WILL PLUNGE TO -3C SOUTH AND -6C NORTH...SUPPORTIVE OF
LOWEST TEMPS IN THE MID 30S TO LOWER 40S. BUT THERE IS TOO MUCH WIND
AND THE GROUNDS ARE TOO WET FOR ANY FROST.
SATURDAY...THE LARGE SCALE EAST COAST TROUGH REMAINS IN
PLACE...WHILE SIMULTANEOUSLY SURFACE HIGH PRESSURE GRADUALLY BUILDS
FROM THE WEST/NW. ANOTHER SHORT WAVE EMBEDDED WITHIN THE DEEP NW
FLOW WILL DROP THROUGH THE UPPER MIDWEST TO NEAR THE SOUTHERN
APPALACHIANS LATE. THIS WILL RESULT IN AN INCREASE IN MID/HIGH LEVEL
CLOUDS OVER THE SW PART OF THE CWFA. ALTHOUGH THERE IS DECENT
INSOLATION...WITH 850 MB TEMPS CLOSE TO 2 STANDARD DEVIATIONS BELOW
NORMAL WE/LL BE HARD PRESSED TO REACH AN MORE THAN 55-60F.
SATURDAY NIGHT...THE AFOREMENTIONED SHORT WAVE WILL PULL THROUGH
OVERNIGHT AND USHER IN A 1033 ARCTIC HIGH FROM THE OHIO VALLEY. THE
ASSOCIATED COLD ADVECTION WILL RESULT IN UNSEASONABLY COLD AIR
PENETRATING INTO THE BULK OF THE FORECAST DISTRICT. THERE LOOKS TO
BE TOO MUCH MIXING TO PREVENT A HARD FREEZE...BUT A LIGHT FREEZE IS
CERTAINLY POSSIBLE ACROSS AT LEAST THE NW TIER. IF WINDS DO DROP OFF
ENOUGH THEN TEMPS COULD BE EVEN COLDER THAN 30-32F IN THESE SECTIONS
AND FROST WOULD ALSO BE A CONCERN IN MANY OTHER COMMUNITIES SOUTH
AND EAST.
SUNDAY...THE EAST COAST TROUGH LIFTS OUT AND GIVES WAY TO SHORT WAVE
RIDGING AND ITS ASSOCIATED RISING HEIGHTS...AS THE CORE OF THE
ARCTIC HIGH SHIFTS DIRECTLY OVERHEAD. DESPITE PLENTIFUL SUNSHINE AND
THE AIR MASS MODIFYING...TEMPS WILL ONLY BE ABLE TO MUSTER THE UPPER
50S AND LOWER 60S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
THE MID LEVEL PATTERN WILL FLATTEN THROUGH THE EARLY AND MIDDLE
PARTS OF NEXT WEEK...ALTHOUGH A SUBTLE IMPULSE WILL MOVE THROUGH
LATE MONDAY/EARLY TUESDAY. THIS WILL FORCE A COLD FRONT THROUGH THE
FORECAST ZONES...ACCOMPANYING ONLY BY MODEST MOISTURE AND JUST
LIMITED CHANCES FOR SHOWERS. THE FRONT THEN WASHES OUT AND GIVES WAY
TO HIGH PRESSURE THROUGH MID WEEK. WARMER CONDITIONS WILL RETURN AS
EVEN THE AIR MASS BEHIND THE COLD FRONT IS OF PACIFIC ORIGIN SO
TEMPS SHOULD GET BACK NEAR OR EVEN ABOVE SEASONAL NORMS.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
KCHS...IFR/LIFR CONDITIONS THROUGH 14Z WILL GIVE WAY TO A RETURN
OF VFR WEATHER FOR THE BALANCE OF THE DAY AS INVERSION WEAKENS AND
LIFTS HIGHER. SOUTH/SW WINDS WILL BE GUSTY DURING THE AFTERNOON AS
UNSEASONABLY TEMPS PREVAIL IN ADVANCE OF A COLD FRONT...WHILE
ENHANCEMENT ALSO OCCURS FROM SEA BREEZE INFLUENCES. CONDITIONS AT
SOME POINT TONIGHT MAY LOWER INTO THE MVFR RANGE AS SHOWERS
DEVELOP IN RESPONSE TO A SHORT WAVE ARRIVING FROM THE GULF AND THE
COLD FRONT APPROACHES FROM THE WEST/NW. UNTIL TRENDS CAN BE BETTER
DEFINED WE HAVE KEPT VFR CONDITIONS GOING THROUGH 12Z
FRIDAY...WITH THE OPTION FOR ADJUSTMENTS AT A LATER TIME.
KSAV...A SHARP INVERSION WILL KEEP THE AIRFIELD LOCKED IN WITH
LIFR CONDITIONS AND NEAR AIRPORT MINIMUMS THROUGH 14Z...BEFORE
IMPROVING BACK TO VFR BY 15Z AS THE INVERSION BREAKS AND MOISTURE
SCOURS OUT. GUSTY SOUTH/SW WINDS WILL THEN PREVAIL FOR THE
HEATING OF THE AFTERNOON IN ADVANCE OF A COLD FRONT...WITH
ADDITIONAL IMPETUS FROM THE SEA BREEZE. CONDITIONS AT
SOME POINT TONIGHT MAY LOWER INTO THE MVFR RANGE AS SHOWERS
DEVELOP IN RESPONSE TO A SHORT WAVE ARRIVING FROM THE GULF AND THE
COLD FRONT APPROACHES FROM THE WEST/NW. UNTIL TRENDS CAN BE BETTER
DEFINED WE HAVE KEPT VFR CONDITIONS GOING THROUGH 12Z
FRIDAY...WITH FUTURE ADJUSTMENTS LIKELY.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS LIKELY FRIDAY IN
ASSOCIATION WITH SCATTERED TO NUMEROUS SHRA AND POSSIBLE TSRA AS A
COLD FRONT MOVES THROUGH. VFR WEATHER WILL THEN PREVAIL LATE FRIDAY
INTO MONDAY...WITH POSSIBLE SUB-VFR WEATHER WITH ANOTHER COLD FRONT
LATE MONDAY.
&&
.MARINE...
TODAY...WEBCAMS OFF HILTON HEAD AND EDISTO BEACH SUGGEST THE SEA
FOG HAS LIFTED SOME OVER THE PAST 1-2 HOURS. HOWEVER...WINDS ARE
FORECAST TO RETURN TO A MOVE SOUTHERLY DIRECTION AS THE MORNING
LAND BREEZE DISSIPATES AND A SEA BREEZE INITIATES. THIS WILL
RETURN THE LOW- LEVEL FLOW TO A MORE FAVORABLE GEOMETRY FOR SEA
FOG DEVELOPMENT. WILL MAINTAIN THE MARINE DENSE FOG ADVISORY FOR
THE NEARSHORE WATERS FROM EDISTO BEACH SOUTH. THE FOG COULD EXPAND
INTO THE CHARLESTON COUNTY WATERS LATER THIS AFTERNOON...SO THE
ADVISORY MAY NEED TO BE EXPANDED WITH LATER FORECAST CYCLES.
TONIGHT...VEERING WINDS AHEAD OF AN APPROACHING COLD FRONT LATE
TONIGHT. WARM AND MOIST AIR MASS WILL REMAIN IN PLACE CREATING A
GOOD ENVIRONMENT FOR SEA FOG. WINDS/SEAS WILL APPROACH SMALL CRAFT
ADVISORY LEVELS LATE TONIGHT BEYOND 20 NM.
FRIDAY...A FAIRLY TIGHT AND CYCLONIC SW PRESSURE PATTERN WILL
PREVAIL IN ADVANCE OF THE COLD FRONT THAT DOESN/T MOVE THROUGH AFTER
1 OR 2 PM. WARM ADVECTION WILL RESTRICT THE AMOUNT OF MIXING...BUT
GIVEN GEOSTROPHIC WINDS OF 30 KT OR SO THIS WILL SUPPORT MARGINAL
SMALL CRAFT ADVISORIES ACROSS THE AMZ374 WATERS FOR GUSTS UP NEAR 25
KT AND SEAS AS HIGH AS 6 FT. WE STILL MIGHT NEED TO EXPAND THE
ADVISORY TO ENCOMPASS AMZ350...BUT FOR NOW THOSE WATERS LOOK TO
REMAIN JUST BELOW ANY ADVISORY CONDITIONS. EVEN THOUGH WIND FIELDS
WILL BE SOMEWHAT ELEVATED...SEA FOG WILL CONTINUE UNTIL THE FRONT
SCOURS THINGS OUT AND VISIBILITIES IMPROVE. MARINERS SHOULD ALSO
REMAIN ALERT FOR POSSIBLE T-STORMS...MOST ESPECIALLY ACROSS THE GULF
STREAM WATERS.
FRIDAY NIGHT AND SATURDAY...A MIXTURE OF COLD ADVECTION AND GOOD
ISALLOBARIC PRESSURE RISES WILL LIKELY SUPPORT ADDITIONAL SMALL
CRAFT ADVISORIES AS NW WINDS APPROACH 20-25 KT IN WAKE OF THE COLD
FRONT AND STRENGTHENING ATLANTIC LOW PRESSURE SOUTH/SE OF NEW ENGLAND.
SATURDAY NIGHT AND SUNDAY...STRONG CONTINENTAL HIGH PRESSURE WILL
BUILD FROM THE NW AND WILL BE ACCOMPANIED BY A SURGE OF NORTH/NE
WINDS AROUND DAYBREAK SUNDAY...BUT LIKELY BENEATH ANY ADVISORY
CRITERIA. THE HIGH WILL THEN SETTLE ATOP THE WATERS BY LATE IN THE
DAY AND WINDS AND SEAS WILL COME DOWN.
MONDAY AND TUESDAY...HIGH PRESSURE EARLY NEXT WEEK WILL GIVE WAY TO
A COLD FRONT THAT MOVES THROUGH BY EARLY TUESDAY...BEFORE BECOMING
DIFFUSE. MARINE CONDITIONS WILL BE AT OR LESS THAN 15 OR 20 KT FOR
WINDS AND LESS THAN 3-5 FOOT SEAS.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ352-354.
SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO 1 PM EDT SATURDAY FOR
AMZ374.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
938 AM EDT THU MAR 26 2015
.UPDATE...
ISSUED AT 938 AM EDT THU MAR 26 2015
THE LINE OF SHOWERS AND THUNDERSTORMS THAT MOVED INTO CENTRAL AND
EASTERN KY THIS MORNING HAS BEEN IN A DETERIORATING STATE FOR THE
LAST COUPLE OF HOURS. AT THIS RATE...MOST OF EASTERN KY WILL
LIKELY SEE SOME SCATTERED LIGHT SHOWERS...BUT NOTHING STRONG
ENOUGH TO PRODUCE THUNDER. FURTHERMORE...DOWNSTREAM...AS
STRATIFORM RAIN BEGINS TO FILL IN ALONG AND BEHIND THE FRONTAL
BOUNDARY...WINDS HAVE ALREADY BEGAN SHIFTING TO THE NE. THIS WILL
CREATE A QUICK SURFACE INVERSION AS COLDER AIR FILTERS IN...AND
WILL ELIMINATE THE THREAT OF THUNDER DEVELOPMENT HERE AS WELL. AS
SUCH...EXPANDED CHANCE AND LIKELY POPS ACROSS OUR CWA AS THIS LINE
BREAKS APART AND SCATTERS OUT OVER THE NEXT COUPLE OF HOURS. ALSO
WENT AHEAD AND REMOVED ANY MENTION OF THUNDER FROM THE FORECAST
FOR THE DURATION OF THE DAY. DID KEEP WITH PREVIOUS FORECAST
MENTION OF CONVECTIVE SHOWERS AHEAD OF THE FRONT...AND MORE
STRATIFORM RAIN BEHIND THE FRONTAL ZONE.
UPDATE ISSUED AT 821 AM EDT THU MAR 26 2015
A LINE OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS HAVE MOVED IN
FROM CENTRAL KENTUCKY THIS MORNING. HAVE FRESHENED UP THE FORECAST
TO ACCOUNT FOR THIS BAND...WHICH WILL GRADUALLY WEAKEN AS IT COMES
EAST. ONCE THIS BAND MOVES THROUGH...STILL EXPECTING ADDITIONAL
ACTIVITY TO INITIATE UPSTREAM AND MOVE IN THIS AFTERNOON...SO
JUST BLENDED INTO THE EXISTING FORECAST AFTER THE MID-MORNING
HOURS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 357 AM EDT THU MAR 26 2015
A SURFACE COLD FRONT IS CURRENTLY ALIGNED FROM NORTHEAST OHIO
DOWN THROUGH NORTH CENTRAL AND SOUTHWESTERN KENTUCKY. CONVECTION
HAS BEEN ONGOING OFF TO OUR WEST...AND HAS BEEN SHOWING A GENERAL
WEAKENING TREND ACCORDING TO THE LIGHTNING DATA AND WARMING CLOUD
TOPS EVIDENT ON THE IR SATELLITE. THERE HAS BEEN SOME NEW
DEVELOPMENT OUT AHEAD OF THE MAIN CLUSTERS...WITH SOME SCATTERED
STORMS POPPING UP JUST EAST OF I-75 IN NORTH CENTRAL KENTUCKY.
EASTERN KENTUCKY REMAINS IN THE WARM SECTOR...ALTHOUGH A FEW
SHELTERED VALLEYS IN OUR FAR EAST HAVE MANAGED TO DROP OFF INTO
THE 40S.
THE MODELS HAVE REMAINED IN PRETTY GOOD AGREEMENT WITH THE
DEVELOPING DEEP LONG WAVE TROUGH TO MOVE EAST ACROSS THE
MISSISSIPPI VALLEY. INITIALLY...HAVE FOLLOWED THE HRRR THROUGH
THIS MORNING...AND THEN A BLEND OF THE MODELS THEREAFTER.
CONVECTION WILL DRAW CLOSER TO THE AREA THROUGH DAWN...WITH AT
LEAST SOME SCATTERED ACTIVITY TO CONTEND WITH THROUGH THE MORNING
HOURS...PARTICULARLY IN THE WESTERN HALF OF THE CWA. THE MAIN
BATCH OF CONVECTION SHOULD STAY TO THE NORTHWEST. A STRENGTHENING
UPPER LEVEL JET ACROSS THE OHIO VALLEY WILL HELP RECHARGE THE
FRONT THIS AFTERNOON...SO WIDESPREAD PRECIPITATION WILL EVENTUALLY
MOVE IN ACROSS ALL OF EASTERN KENTUCKY THROUGH EARLY THIS EVENING.
SHOWERS AND SCATTERED THUNDERSTORMS WILL GIVE WAY TO MAINLY RAIN
BEHIND THE DEPARTING COLD FRONT...WITH THE SOUTHEAST LIKELY SEEING
THE HIGHER AMOUNTS OF QPF...WHERE A HALF INCH OR MORE COULD FALL.
DRY SLOTTING WILL WORK IN TONIGHT BEHIND AN INITIAL DEPARTING
SHORT WAVE TROUGH...WITH MOISTURE LIKELY CUTTING OFF BEFORE
TEMPERATURES GET COLD ENOUGH TO SUPPORT A FEW FLAKES. ON
FRIDAY...THE MAIN TROUGH AXIS WILL MOVE THROUGH THE AREA DURING
THE AFTERNOON HOURS...ALLOWING FOR SOME ISOLATED TO SCATTERED
SHOWERS.
HIGHS TODAY WILL LIKELY BE ESTABLISHED IN THE MORNING FOR MOST
LOCATIONS. READINGS WILL RANGE FROM AROUND 60 IN THE FAR
NORTHWEST...TO THE LOW TO MID 70S IN FAR EAST AND SOUTHEAST.
TEMPERATURES WILL FALL OFF TO THE 40S AND 50S BY LATE IN THE
DAY...WITH LOWS TONIGHT BOTTOMING OUT IN THE LOW TO MID 30S. HIGHS
ON FRIDAY WILL ONLY RECOVER TO THE 40S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 357 PM EDT WED MAR 25 2015
GUIDANCE IS IN GOOD AGREEMENT WITH THE BASE OF THE AMPLIFIED
TROUGH AXIS MOVING ACROSS THE OHIO VALLEY TO BEGIN THE PERIOD.
UNDER NORTHWEST FLOW AND COLDER AIR ALOFT MOVING ACROSS BASED ON
FORECAST SOUNDINGS...IT SEEMS REASONABLE TO MAINTAIN SMALL CHANCES
OF RAIN SHOWERS FRIDAY EVENING. AS WE COOL OFF...WOULD EXPECT A
CHANGE OVER TO A MIX/SNOW SHOWERS FRIDAY NIGHT PARTICULARLY
ACROSS THE FAR SE. BASED ON FORECAST SOUNDINGS WE REALLY DRY OUT
IN THE UPPER LEVELS BY SATURDAY MORNING...BUT SOUNDINGS TRY TO AT
LEAST HOLD ON TO SOME HIGH LEVEL CLOUDS. GIVEN THE COLD AIR MASS
IN PLACE WITH H850 SUB MINUS 10 IT WILL BE A COLD NIGHT WITH LOWS
IN THE LOW TO MID 20S. THIS UPPER LEVEL TROUGH CONTINUES TO SLIDE
EAST SATURDAY WITH THE COLD AIR MASS KEEPING HIGHS IN THE UPPER
30 TO LOWER 40S MOST SPOTS.
THE CANADIAN HIGH WILL CONTINUE TO BUILD SOUTHEAST SATURDAY INTO
SATURDAY NIGHT. THIS WILL BE THE BEST NIGHT FOR CLEAR SKIES AND
FROST. RIGHT NOW IT ALL DEPENDS ON HOW THE HIGH ALIGNS ACROSS THE
REGION TO WHERE THE MAX POTENTIAL FOR COOLING WILL BE. THE HIGH
SLIDES EAST FOR SUNDAY USHERING IN RETURN FLOW AND WARMER TEMPS.
WHILE UNCERTAINTY REMAINS ON THE EXACT EVOLUTION OF THE SYSTEM
MOVING INTO THE BEGINNING OF NEXT WEEK WITH A MORE PROGRESSIVE
GFS VERSUS OTHER GUIDANCE...EITHER WAY IT DOES LOOK LIKE CHANCES
OF RAIN SHOWERS INCREASE SUNDAY NIGHT INTO MONDAY. THERE IS ANOTHER
POTENTIAL SYSTEM BY MID WEEK WITH MODEL UNCERTAINTY REMAINING
HERE. THE GFS IS AGAIN QUICKER...WITH MORE OF A SOUTHERN STREAM
INFLUENCE VERSUS THE ECMWF NORTHERN STREAM FRONT BEING THE BIGGER
INFLUENCE. GIVEN THE UNCERTAINTY IN THESE SYSTEMS...DID STICK
CLOSE TO A MODEL BLEND...WHICH KEEPS SLIGHT TO CHANCE POPS WITH
BOTH SYSTEMS. OTHERWISE THE BEST BREAK IN THE ACTIVE PATTERN
LOOKS TO BE ON TUESDAY IN BETWEEN THESE SYSTEMS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 821 AM EDT THU MAR 26 2015
VFR CONDITIONS WILL GIVE WAY TO MVFR THROUGH 16Z AS CONVECTION
MOVES THROUGH IN RESPONSE TO A COLD FRONT SHIFTING SOUTHEAST
ACROSS THE AREA. WIDESPREAD PRECIPITATION AND CEILINGS LOWERING TO
IFR ARE EXPECTED LATER TODAY. THE RAIN WILL TAPER OFF FROM
NORTHWEST TO SOUTHEAST THIS EVENING AND INTO THE OVERNIGHT...WITH
CEILINGS RAISING UP TO MVFR AND EVENTUALLY VFR BETWEEN 4 AND 10Z
FRIDAY. SOUTHWEST WINDS OF AROUND 10 KTS...WITH GUSTS RANGING
FROM 15 TO 20 KTS...WILL SHIFT TO THE NORTHWEST AS THE FRONT
PASSES BY TO THE SOUTHEAST TODAY. WINDS WILL DIMINISH AND BECOME
MORE OUT OF THE NORTH TONIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GEOGERIAN
LONG TERM...DJ
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
821 AM EDT THU MAR 26 2015
.UPDATE...
ISSUED AT 821 AM EDT THU MAR 26 2015
A LINE OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS HAVE MOVED IN
FROM CENTRAL KENTUCKY THIS MORNING. HAVE FRESHENED UP THE FORECAST
TO ACCOUNT FOR THIS BAND...WHICH WILL GRADUALLY WEAKEN AS IT COMES
EAST. ONCE THIS BAND MOVES THROUGH...STILL EXPECTING ADDITIONAL
ACTIVITY TO INITIATE UPSTREAM AND MOVE IN THIS AFTERNOON...SO
JUST BLENDED INTO THE EXISTING FORECAST AFTER THE MID-MORNING
HOURS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 357 AM EDT THU MAR 26 2015
A SURFACE COLD FRONT IS CURRENTLY ALIGNED FROM NORTHEAST OHIO
DOWN THROUGH NORTH CENTRAL AND SOUTHWESTERN KENTUCKY. CONVECTION
HAS BEEN ONGOING OFF TO OUR WEST...AND HAS BEEN SHOWING A GENERAL
WEAKENING TREND ACCORDING TO THE LIGHTNING DATA AND WARMING CLOUD
TOPS EVIDENT ON THE IR SATELLITE. THERE HAS BEEN SOME NEW
DEVELOPMENT OUT AHEAD OF THE MAIN CLUSTERS...WITH SOME SCATTERED
STORMS POPPING UP JUST EAST OF I-75 IN NORTH CENTRAL KENTUCKY.
EASTERN KENTUCKY REMAINS IN THE WARM SECTOR...ALTHOUGH A FEW
SHELTERED VALLEYS IN OUR FAR EAST HAVE MANAGED TO DROP OFF INTO
THE 40S.
THE MODELS HAVE REMAINED IN PRETTY GOOD AGREEMENT WITH THE
DEVELOPING DEEP LONG WAVE TROUGH TO MOVE EAST ACROSS THE
MISSISSIPPI VALLEY. INITIALLY...HAVE FOLLOWED THE HRRR THROUGH
THIS MORNING...AND THEN A BLEND OF THE MODELS THEREAFTER.
CONVECTION WILL DRAW CLOSER TO THE AREA THROUGH DAWN...WITH AT
LEAST SOME SCATTERED ACTIVITY TO CONTEND WITH THROUGH THE MORNING
HOURS...PARTICULARLY IN THE WESTERN HALF OF THE CWA. THE MAIN
BATCH OF CONVECTION SHOULD STAY TO THE NORTHWEST. A STRENGTHENING
UPPER LEVEL JET ACROSS THE OHIO VALLEY WILL HELP RECHARGE THE
FRONT THIS AFTERNOON...SO WIDESPREAD PRECIPITATION WILL EVENTUALLY
MOVE IN ACROSS ALL OF EASTERN KENTUCKY THROUGH EARLY THIS EVENING.
SHOWERS AND SCATTERED THUNDERSTORMS WILL GIVE WAY TO MAINLY RAIN
BEHIND THE DEPARTING COLD FRONT...WITH THE SOUTHEAST LIKELY SEEING
THE HIGHER AMOUNTS OF QPF...WHERE A HALF INCH OR MORE COULD FALL.
DRY SLOTTING WILL WORK IN TONIGHT BEHIND AN INITIAL DEPARTING
SHORT WAVE TROUGH...WITH MOISTURE LIKELY CUTTING OFF BEFORE
TEMPERATURES GET COLD ENOUGH TO SUPPORT A FEW FLAKES. ON
FRIDAY...THE MAIN TROUGH AXIS WILL MOVE THROUGH THE AREA DURING
THE AFTERNOON HOURS...ALLOWING FOR SOME ISOLATED TO SCATTERED
SHOWERS.
HIGHS TODAY WILL LIKELY BE ESTABLISHED IN THE MORNING FOR MOST
LOCATIONS. READINGS WILL RANGE FROM AROUND 60 IN THE FAR
NORTHWEST...TO THE LOW TO MID 70S IN FAR EAST AND SOUTHEAST.
TEMPERATURES WILL FALL OFF TO THE 40S AND 50S BY LATE IN THE
DAY...WITH LOWS TONIGHT BOTTOMING OUT IN THE LOW TO MID 30S. HIGHS
ON FRIDAY WILL ONLY RECOVER TO THE 40S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 357 PM EDT WED MAR 25 2015
GUIDANCE IS IN GOOD AGREEMENT WITH THE BASE OF THE AMPLIFIED
TROUGH AXIS MOVING ACROSS THE OHIO VALLEY TO BEGIN THE PERIOD.
UNDER NORTHWEST FLOW AND COLDER AIR ALOFT MOVING ACROSS BASED ON
FORECAST SOUNDINGS...IT SEEMS REASONABLE TO MAINTAIN SMALL CHANCES
OF RAIN SHOWERS FRIDAY EVENING. AS WE COOL OFF...WOULD EXPECT A
CHANGE OVER TO A MIX/SNOW SHOWERS FRIDAY NIGHT PARTICULARLY
ACROSS THE FAR SE. BASED ON FORECAST SOUNDINGS WE REALLY DRY OUT
IN THE UPPER LEVELS BY SATURDAY MORNING...BUT SOUNDINGS TRY TO AT
LEAST HOLD ON TO SOME HIGH LEVEL CLOUDS. GIVEN THE COLD AIR MASS
IN PLACE WITH H850 SUB MINUS 10 IT WILL BE A COLD NIGHT WITH LOWS
IN THE LOW TO MID 20S. THIS UPPER LEVEL TROUGH CONTINUES TO SLIDE
EAST SATURDAY WITH THE COLD AIR MASS KEEPING HIGHS IN THE UPPER
30 TO LOWER 40S MOST SPOTS.
THE CANADIAN HIGH WILL CONTINUE TO BUILD SOUTHEAST SATURDAY INTO
SATURDAY NIGHT. THIS WILL BE THE BEST NIGHT FOR CLEAR SKIES AND
FROST. RIGHT NOW IT ALL DEPENDS ON HOW THE HIGH ALIGNS ACROSS THE
REGION TO WHERE THE MAX POTENTIAL FOR COOLING WILL BE. THE HIGH
SLIDES EAST FOR SUNDAY USHERING IN RETURN FLOW AND WARMER TEMPS.
WHILE UNCERTAINTY REMAINS ON THE EXACT EVOLUTION OF THE SYSTEM
MOVING INTO THE BEGINNING OF NEXT WEEK WITH A MORE PROGRESSIVE
GFS VERSUS OTHER GUIDANCE...EITHER WAY IT DOES LOOK LIKE CHANCES
OF RAIN SHOWERS INCREASE SUNDAY NIGHT INTO MONDAY. THERE IS ANOTHER
POTENTIAL SYSTEM BY MID WEEK WITH MODEL UNCERTAINTY REMAINING
HERE. THE GFS IS AGAIN QUICKER...WITH MORE OF A SOUTHERN STREAM
INFLUENCE VERSUS THE ECMWF NORTHERN STREAM FRONT BEING THE BIGGER
INFLUENCE. GIVEN THE UNCERTAINTY IN THESE SYSTEMS...DID STICK
CLOSE TO A MODEL BLEND...WHICH KEEPS SLIGHT TO CHANCE POPS WITH
BOTH SYSTEMS. OTHERWISE THE BEST BREAK IN THE ACTIVE PATTERN
LOOKS TO BE ON TUESDAY IN BETWEEN THESE SYSTEMS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 821 AM EDT THU MAR 26 2015
VFR CONDITIONS WILL GIVE WAY TO MVFR THROUGH 16Z AS CONVECTION
MOVES THROUGH IN RESPONSE TO A COLD FRONT SHIFTING SOUTHEAST
ACROSS THE AREA. WIDESPREAD PRECIPITATION AND CEILINGS LOWERING TO
IFR ARE EXPECTED LATER TODAY. THE RAIN WILL TAPER OFF FROM
NORTHWEST TO SOUTHEAST THIS EVENING AND INTO THE OVERNIGHT...WITH
CEILINGS RAISING UP TO MVFR AND EVENTUALLY VFR BETWEEN 4 AND 10Z
FRIDAY. SOUTHWEST WINDS OF AROUND 10 KTS...WITH GUSTS RANGING
FROM 15 TO 20 KTS...WILL SHIFT TO THE NORTHWEST AS THE FRONT
PASSES BY TO THE SOUTHEAST TODAY. WINDS WILL DIMINISH AND BECOME
MORE OUT OF THE NORTH TONIGHT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...GEOGERIAN
LONG TERM...DJ
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS DULUTH MN
943 AM CDT THU MAR 26 2015
.UPDATE...
ISSUED AT 942 AM CDT THU MAR 26 2015
EXTENDED THE LAKE SNOW ADVISORY FOR IRON COUNTY UNTIL 05Z FRI AFTER
COORDINATION WITH MQT AND THE RAP SOUNDINGS INDICATING THE WINDS
STAY FAVORABLE FOR SNOW SHOWERS THROUGH THIS EVENING. A SHORTWAVE
WILL MOVE THROUGH THE REGION TONIGHT WHICH SHOULD SWITCH THE
WINDS. CURRENT WEBCAMS AND REPORTS INDICATE SNOW SHOWERS IS STILL
COMING DOWN.
ALSO...MADE ADJUSTMENTS TO CLOUD COVER AND TEMPS BASED ON CURRENT
TRENDS ON SATELLITE AND CURRENT OBS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 309 AM CDT THU MAR 26 2015
A MUCH COOLER AND DRIER AIR MASS DESCENDS INTO THE UPPER MIDWEST
TODAY. PRIMARY FORECAST CONCERN IS LAKE EFFECT SNOW SHOWERS ALONG
THE SOUTH SHORE OF LAKE SUPERIOR. OTHERWISE COOL AND DRY AS HIGH
PRESSURE MOVES ACROSS NORTHERN MINNESOTA TONIGHT INTO TOMORROW.
SOUTH SHORE OF LAKE SUPERIOR...THE LAKE EFFECT SNOW SHOWERS ARE
BEGINNING TO INTENSIFY AS OF 08Z/3AM CDT AND WILL PERSIST THROUGH
THIS MORNING. WITH A VERY DRY AIR MASS MOVING IN FROM THE NORTH THE
WINDOW FOR THE BEST LAKE EFFECT ENVIRONMENT WILL BE CLOSING THIS
AFTERNOON...AND GIVEN THE LATEST SUITE OF GUIDANCE HAVE DECIDED TO
DECREASE SNOW TOTALS BY A BIT. WILL LIKELY LET THE CURRENT ADVISORY
FOR IRON COUNTY RUN THROUGH THE EARLY MORNING HOURS...SINCE REVISED
LOWER SNOWFALL AMOUNTS OF TWO TO FOUR INCHES IS STILL WITHIN THE
ADVISORY CRITERIA. SNOWFALL TAPERS OFF THIS AFTERNOON BUT COULD SEE
ANOTHER PULSE OF SNOW SHOWERS THIS EVENING AS LOW LEVEL WINDS VEER
FROM THE NORTH TO NORTHEAST RESULTING IN A LONGER FETCH...BUT
SNOWFALL AMOUNTS THIS EVENING WOULD LIKELY ONLY BE AN INCH OR TWO.
ADDED SOME GENEROUS FLURRIES INTO PARTS OF NORTHWEST WISCONSIN BASED
OFF SOME OF THE MORE AGGRESSIVE CONVECTION-ALLOWING GUIDANCE...BUT
GENERALLY ACCUMULATING SNOWFALL WILL BE LIMITED TO HIGHER TERRAIN
ALONG THE SOUTH SHORE.
ELSEWHERE TODAY...DECREASING CLOUDS IN THE MORNING BECOMING SUNNY
THIS AFTERNOON. BREEZY NORTH/NORTHWEST WINDS EARLY THIS MORNING
BECOMING LIGHT OUT OF THE NORTH AT 5 TO 15 MPH LATE IN THE MORNING
INTO THE AFTERNOON. COOLER...HIGH TEMPERATURES IN THE MID 20S TO MID 30S.
TONIGHT...CLEAR SKIES AND COLD. NEAR CALM WINDS AS THE HIGH PRESSURE
BECOMES CENTERED OVER NORTHERN MINNESOTA. TEMPERATURES IN THE SINGLE
DIGITS TO LOW TEENS...WITH LOWS NEAR ZERO IN THE TIP OF THE
ARROWHEAD.
FRIDAY...SUNNY AND DRY. A FEW HIGH CLOUDS LATE IN THE DAY BUT
OTHERWISE SUNNY. WINDS BECOMING SOUTHERLY AND LIGHT AT LESS THAN 10
MPH. RELATIVE HUMIDITY VALUES COULD DROP TO 25 TO 35 PERCENT IN THE
AFTERNOON...BUT THERE ARE NO FIRE WEATHER CONCERNS DUE TO WEAK
WINDS. TEMPERATURES COOL...HIGHS IN THE LOW TO MID 30S...EXCEPT
ALONG THE TIP OF THE ARROWHEAD WHERE TEMPERATURES WILL BE LIMITED TO
THE MID 20S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 309 AM CDT THU MAR 26 2015
THE UPPER FLOW WILL BE NORTHWEST THROUGH MUCH OF THE PERIOD A
WESTERN RIDGE PERSISTING. THE FLOW IS FORECAST TO BECOME MORE ZONAL
LATE IN THE PERIOD. SEVERAL SHORTWAVES WILL MOVE THROUGH THE REGION
DURING THE PERIOD BRINGING A CHANCE FOR PRECIPITATION TO THE
NORTHLAND.
A DEPARTING SURFACE HIGH AND UPPER RIDGE WILL CAUSE DRY CONDITIONS
FRIDAY NIGHT INTO SATURDAY. WE LOWERED TEMPS FRIDAY NIGHT AS LIGHT
WINDS AND CLEAR SKIES ARE EXPECTED. SATURDAY WILL FEATURE THICKENING
CLOUDS AS MID LEVEL WAA DEVELOPS.
AN AREA OF LOW PRESSURE AND STRONG SHORTWAVE WILL START TO IMPACT
THE NORTHLAND SATURDAY NIGHT AND CONTINUE INTO SUNDAY. THE MODELS
ARE IN AGREEMENT BRINGING THIS SYSTEM THROUGH...BUT ARE NOT IN GOOD
AGREEMENT REGARDING THE DETAILS OF TIMING AND AMOUNT OF LOW LEVEL
WARM AIR THAT WILL BE IN PLACE. WE DID INCREASE POPS LATE SATURDAY
NIGHT INTO SUNDAY...AND MAY HAVE TO FURTHER. A MIX OF SNOW AND
RAIN...AND POSSIBLY SOME SLEET WILL BE POSSIBLE. SOME LIGHT SNOW
ACCUMULATIONS WILL BE POSSIBLE...MAINLY ALONG AND NORTHEAST OF
HIGHWAY 53.
WEAKER SYSTEMS ARE POSSIBLE SUNDAY NIGHT INTO TUESDAY WITH PERIODIC
CHANCES FOR SOME LIGHT PRECIPITATION. BOTH THE GFS AND ECMWF ARE
SHOWING A STRONGER AREA OF LOW PRESSURE AT THE END OF THE
PERIOD...AND INITIALLY LOOKS WARM ENOUGH FOR MOSTLY RAIN.
HIGH TEMPERATURES THROUGH MOST OF THE EXTENDED WILL BE ABOVE NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 708 AM CDT THU MAR 26 2015
MAINLY MVFR CONDITIONS COVERED THE NORTHLAND EARLY THIS MORNING
WITH SCATTERED SNOW SHOWERS. CLEARING WAS OCCURRING OVER PORTIONS
OF NORTHERN MINNESOTA AND ALONG THE NORTH SHORE. OVERALL...THE
TREND WILL BE FOR DECREASING CLOUDS THROUGH THE DAY WITH MOSTLY
CLEAR SKIES TONIGHT. CLOUDS WILL BE MORE NUMEROUS ALONG THE SOUTH
SHORE AND POSSIBLY AS FAR INLAND AS KHYR DUE TO LAKE PROCESSES.
GUSTY WINDS THIS MORNING WILL GRADUALLY DIMINISH THROUGH THE
AFTERNOON INTO THE EARLY EVENING HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 30 13 30 14 / 10 0 0 10
INL 26 7 35 14 / 10 0 0 0
BRD 34 13 36 18 / 0 0 0 0
HYR 31 10 35 11 / 30 10 0 0
ASX 28 15 30 10 / 30 40 10 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR WIZ004.
LS...SMALL CRAFT ADVISORY UNTIL 11 AM CDT THIS MORNING FOR LSZ121-
145>148.
&&
$$
UPDATE...STEWART
SHORT TERM...JJM
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1043 AM CDT THU MAR 26 2015
.UPDATE...LARGE EXPANSE OF CONVECTION THIS MORNING ALONG THE NORTHERN
GULF COAST EFFECTIVELY SERVING TO CUT OFF NORTHERLY ADVECTION OF RICH
GULF MOISTURE. SURFACE COLD FRONT MOVING THROUGH CENTRAL AR INTO NW
LA AT THE MOMENT. OTHER THAN CLOUD COVER...ONLY A BROKEN BAND OF
SHOWERS IS ASSOCIATED WITH THE FRONT.
HRRR MODEL IS INDICATING A NARROW WINDOW POTENTIAL FOR SOME ROBUST
CONVECTION OVER SE MS THIS AFTERNOON. WHILE AGREE THAT SE PORTIONS
WILL HAVE THE BEST CHANCE FOR CONVECTIVE DEVELOPMENT...BELIEVE HRRR
SOLUTION MAY BE SOMEWHAT OVERDONE. HRRR DID NOT INITIALIZE THE
COASTAL CONVECTION VERY WELL AND AS A RESULT LOOKS TO BE OVERDOING
THE ADVANCEMENT OF RICH MOISTURE INLAND./26/
&&
.AVIATION...MOST SITES ARE VFR THIS MORNING WITH THE EXCEPTION OF
HBG/MEI WHERE FOG/STRATUS HAVE CONTINUED. EXPECT ALL SITES TO BECOME
VFR BY 16- 17Z...BUT A COLD FRONT IS MOVING INTO THE DELTA WITH
SHOWERS FORMING ALONG THE BOUNDARY. THE COLD FRONT WILL MOVE SOUTH
ACROSS THE AREA AND THIS WILL BRING SHOWERS/THUNDERSTORMS AND BRIEF
PERIODS OF MVFR/IFR CONDITIONS TO ALL SITES LATER THIS MORNING
THROUGH THE AFTERNOON HOURS. LIGHT SOUTHERLY WINDS WILL BECOME MORE
SOUTHWEST AND EVENTUALLY WILL INCREASE TO 10-15G20KT OUT OF NORTHWEST
AT GLH/GWO/JAN/HKS LATER THIS AFTERNOON./15/
&&
.PREV DISCUSSION... /ISSUED 325 AM CDT THU MAR 26 2015/
DISCUSSION...SHORT TERM...TODAY THROUGH FRIDAY NIGHT...LATEST
SATELLITE IMAGERY INDICATED A BROAD UPPER TROUGH EXTENDING FROM THE
NORTHERN MISSISSIPPI VALLEY DOWN TO THE SOUTHERN PLAINS. THIS WAS
ASSOCIATED WITH A SLOW MOVING COLD FRONT EXTENDING FROM THE OHIO
VALLEY TO THE SOUTHERN PLAINS. CONVECTION WAS OCCURRING OVER THE
SOUTHERN PLAINS THROUGH THE OZARKS. THE MAIN FOCUS IS ON THE FRONT
PUSHING THROUGH THE CWA FOR TODAY AND THE COOL DOWN IN TEMPS IN ITS
WAKE. WITH SOME BREEZY NORTH WINDS TEMPS WILL COOL DOWN INTO THE 50S
BEHIND THE FRONT OVER MOST OF THE REGION BY LATE AFTERNOON. HIRES AND
SREF PROBS SHOWS SOME PATCHY FOG ACROSS THE SOUTHEAST WHERE THE LOW
LEVEL FLOW WILL BE LIGHT UNTIL MID MORNING. THE MAIN FORCING DYNAMICS
WILL SHIFT NORTH OF THE REGION BY THE TIME THE FRONT PUSHES THROUGH
THE ARKLAMISS TODAY. HOWEVER WE WILL HAVE ENOUGH LAPSE RATES AND
MODERATE INSTABILITY FOR SOME CONVECTION FOR LATE THIS MORNING
THROUGH THIS EVENING. WITH LIMITED FORCING HIRES MODELS DO NOT SHOW
ANY SEVERE STORMS AS FRONT PUSHES THROUGH. MOST OF THE RAINS WILL BE
POST FRONTAL WITH SOME ELEVATED CONVECTION UNTIL THE 03Z. RAINFALL
AMOUNTS WILL BE FROM A HALF TO AROUND 1.5 INCHES ACCORDING TO HIRES
GUIDANCE WITH PWATS AROUND 1.3 INCHES. AFTER 03Z ONLY SOME LIGHT
SHOWERS WILL LINGER IN THE SOUTHEAST AND END PRIOR TO DAWN FRIDAY.
OVERNIGHT LOWS WILL COOL INTO THE 30S AND 40S. THE UPPER TROUGH AXIS
WILL CROSS THE REGION FOR TONIGHT INTO FRIDAY. FOR FRIDAY UNDER FULL
INSOLATION IT WILL BE A COOLER DAY WITH HIGHS IN THE MIDDLE 50S NORTH
TO THE LOWER 60S SOUTH. THIS WILL BE AROUND 10 TO 15 DEGREES BELOW
NORMAL FOR THIS TIME OF YEAR. FOR FRIDAY NIGHT LOWS WILL ONCE AGAIN
BE IN THE 30S AND 40S...WHICH WILL BE UP TO AROUND 10 DEGREES BELOW
NORMAL./17/
LONGTERM...SATURDAY THROUGH NEXT THURSDAY...A WEAK DISTURBANCE
EMBEDDED IN NORTHWEST FLOW ALOFT IS ADVERTISED TO DROP SOUTHEAST AND
INTO THE DEEP SOUTH ON SATURDAY. THIS WILL BRING CLOUDS AND RAIN
CHANCES TO MAINLY THE NORTHEAST HALF OF THE CWA. BOTH WILL CLEAR
OUT OF THE REGION SATURDAY NIGHT AS HIGH PRESSURE QUICKLY BUILDS
INTO AND THROUGH THE FORECAST AREA SUNDAY.
SOUTHERLY FLOW AT THE SURFACE WILL ENSUE SUNDAY INTO SUNDAY NIGHT AS
ANOTHER COLD FRONT APPROACHES THE FORECAST AREA FROM THE NORTH. AS
MID/UPPER LEVEL FLOW BECOMES MORE QUASI-ZONAL HEADING INTO THE NEW
WORK WEEK...THIS FRONT WILL STALL OVER THE CWA MONDAY INTO TUESDAY.
HEADING INTO MID-WEEK...THIS FRONT WILL LIFT BACK TO THE NORTH IN
RESPONSE TO A SHORTWAVE EMBEDDED IN WESTERLY FLOW APPROACHING AND
PUSHING THROUGH THE FORECAST AREA WEDNESDAY NIGHT INTO THURSDAY.
ALL THE ABOVE WILL ESSENTIALLY RESULT IN RAIN CHANCES LINGERING IN
THE FORECAST MONDAY THROUGH THURSDAY...WITH WARM CONDITIONS EXPECTED
DURING THIS TIME. THE BETTER CHANCES FOR SHOWERS AND STORMS LOOK TO
COME PRIMARILY DURING THE AFTERNOON HOURS...THE ONLY EXCEPTION BEING
WEDNESDAY NIGHT AS THE BEFORE MENTIONED SHORTWAVE PUSHES INTO AND
THROUGH THE REGION. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 74 39 59 40 / 67 37 6 2
MERIDIAN 75 41 60 39 / 51 55 9 1
VICKSBURG 71 39 61 42 / 73 25 3 2
HATTIESBURG 74 44 63 42 / 52 41 6 2
NATCHEZ 72 41 63 43 / 65 25 4 2
GREENVILLE 65 38 58 40 / 66 17 7 2
GREENWOOD 66 35 56 38 / 60 27 7 2
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
920 AM MDT THU MAR 26 2015
.UPDATE...
NO SIGNIFICANT CHANGES TO THE GOING FORECAST FOR TODAY. WE STILL
HAVE AN UNSTABLE NORTHWEST FLOW OVER US THAT IS SLOWLY BECOMING
MORE ANTI CYCLONIC. ANY MEASURABLE PRECIPITATION TODAY SHOULD
GENERALLY BE LIMITED TO THE SOUTHEAST AND ALONG THE BIG HORNS
REGION. BT
&&
.SHORT TERM...VALID FOR TDY AND FRI...
STRONG UPPER LEVEL RIDGE EXISTS ALONG THE WEST COAST BUT IT IS
DIRTY...WITH AN ABUNDANCE OF PACIFIC MOISTURE SPILLING OVER THE
RIDGE IN THE NW FLOW OVER OUR REGION. WEAK ENERGY DROPPING INTO
THE NORTHERN PLAINS WITH A 140KT H3 JET OVER EASTERN MT IS
PRODUCING SOME LIGHT PCPN NEAR THE DAKOTAS BORDER...WHICH WILL
SHIFT EAST OF OUR CWA OVER THE COMING HOURS. NW FLOW IS ALSO
GENERATING SOME LIGHT SHOWERS OR SPRINKLES IN UPSLOPE AREAS S/SE
OF BILLINGS AND OVER THE MTNS. LOOKING UPSTREAM...AREAS OF LIGHT
PCPN IMPACT WESTERN MT AS WELL. OVERALL WE SHOULD SEE CLOUDY SKIES
PERSIST TODAY DESPITE THE SLOWLY BUILDING HEIGHTS WITH AREAS OF
LIGHT SHOWERS OR SPRINKLES...MAINLY OVER THE MTNS AND IN UPSLOPE
REGIONS BUT THERE MAY BE ENOUGH DIURNAL INSTABILITY WITH STEEP MID
LEVEL LAPSE RATES TO PRODUCE SOME SPRINKLES ELSEWHERE INCLUDING
BILLINGS...AS RECENT HRRR RUNS SUGGEST. ANOTHER PIECE OF ENERGY
WILL DROP INTO THE NORTHERN PLAINS TONIGHT AND THIS SHOULD ENHANCE
PCPN AGAIN NEAR THE DAKOTAS BORDER...IE NEAR AND EAST OF SFC TROF.
OTHERWISE WE WILL SEE DRYING FROM WEST TO EAST LATE TONIGHT INTO
FRIDAY AS THE RIDGE CONTINUES TO PUSH EAST INTO THE NORTHERN
ROCKIES. DOWNSLOPE GRADIENTS WILL PERSIST FOR GUSTY WINDS ALONG
OUR FOOTHILLS OVER THE NEXT TWO DAYS. DO NOT EXPECT ANY HIGHLIGHTS
BUT BIG TIMBER HAS BEEN GUSTING INTO THE 40S ALREADY. HAVE RAISED
WIND SPEEDS SOME FROM BIG TIMBER TO 3HT AS THESE AREAS ARE FAVORED
IN A NW FLOW CHINOOK. TEMPS WILL RISE INTO THE LOWER TO MID 60S
TODAY IN WEST AND CENTRAL PARTS...AND INTO THE LOWER 70S FRIDAY.
HIGHS WILL APPROACH RECORDS AT LIVINGSTON AND BILLINGS ON FRIDAY.
THINGS GET MORE INTERESTING SATURDAY AS THE UPPER RIDGE BREAKS
DOWN WITH THE PASSAGE OF A PACIFIC SHORTWAVE AND COLD FRONT.
MODELS CONTINUE TO DISAGREE IN THE AMOUNT OF SPLITTING THAT THIS
ENERGY WILL UNDERGO IN THE EASTERN PACIFIC BEFORE IT MOVES INLAND.
LATEST ECMWF AND CANADIAN HAVE TRENDED SLOWER AND STRONGER WITH
THE WAVE...WHEREAS THE GFS IS CONTINUING WITH A WEAKER NORTHERN
SPLIT AND IS THUS FASTER. GIVEN THIS FEATURE IS IN A DATA VOID
AREA OVER THE PACIFIC AM NOT SURE WHICH SCENARIO IS PREFERRED SO
WILL STAY WITH A COMPROMISE AT THIS TIME. OVERALL EXPECT A FRONTAL
PASSAGE BY AFTERNOON WITH INCREASED SHOWER ACTIVITY ALONG AND
BEHIND THE FRONT. A SLOWER TIMING OF THIS FRONT WOULD YIELD WARMER
PREFRONTAL CONDITIONS AND THE POSSIBILITY OF A FEW TSTMS...AS THE
NAM AND ECMWF SHOW LIFTED INDICES NEAR ZERO. MAIN ISSUES ON
SATURDAY WILL REVOLVE AROUND FIRE WEATHER AND WIND AND WILL
CONTINUE TO HIGHLIGHT POTENTIAL FOR HIGH TEMPS...LOW RHS...STRONG
WINDS AND A FRONTAL PASSAGE IN THE FIRE WEATHER FORECAST. ALL
MODELS SHOWING NEAR 50 KTS OF MID LEVEL WIND WITH THIS SYSTEM SO
AN AFTERNOON ONSET OF SUBSIDENCE COULD PRODUCE VERY STRONG WINDS
ESPECIALLY FOR OUR WESTERN PARTS. STRONG W-NW WINDS SHOULD PUSH
ACROSS OUR PLAINS BY SATURDAY NIGHT. AGAIN...STRESS THE TIMING
UNCERTAINTY HERE.
ANYONE PLANNING OUTDOOR ACTIVITIES ON SATURDAY SHOULD BE AWARE OF
THE POTENTIAL FOR STRONG WINDS AND MONITOR THE FORECAST.
JKL
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
MEDIUM RANGE GUIDANCE IN OVERALL GOOD AGREEMENT INTO THE EXTENDED.
UPPER HEIGHTS BUILD ACROSS THE NORTHERN ROCKIES FOR SUNDAY INTO
MONDAY BEHIND SATURDAYS SYSTEM FOR DRY CONDITIONS. NEXT VIGOROUS
SYSTEM TO BREAK DOWN THE RIDGE ON TUESDAY. THIS SYSTEM NOT LOOKING
LIKE A BIG PRECIP MAKER WITH DOWNSLOPE FLOW...BUT COULD BE
ANOTHER WIND PRODUCER. BEHIND THE TUESDAY SYSTEM...AN OVERALL
PRGRESSIVE FLOW PATTERN DEVELOPS WITH MUCH LESS AMPLIFICATION.
THIS WILL PUSH SEVERAL IMPULSES THROUGH THE FLOW AND KEEP A FEW
SHOWERS IN THE FORECAST INTO NEXT THURSDAY. HIGH TEMPERATURES WILL
COOL TO MORE SEASONAL LEVELS INTO THE 50S. FRIEDERS
&&
.AVIATION...
VFR CONDITIONS CAN BE EXPECTED THROUGH TONIGHT. ISOLATED LIGHT
SHOWERS ARE POSSIBLE MAINLY EAST OF A KBIL TO KSHR LINE...AND NEAR
THE MOUNTAINS. OTHERWISE...MAINLY MID LEVEL CLOUDS WILL BE AROUND
WITH SOME VIRGA INTO THIS AFTERNOON. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY FRI SAT SUN MON TUE WED
-------------------------------------------------------
BIL 065 045/073 048/073 040/065 041/070 045/065 038/058
1/E 00/B 03/W 20/B 00/U 03/W 22/W
LVM 065 044/073 047/067 037/065 040/068 042/058 031/055
1/N 00/N 03/W 21/B 00/U 14/W 22/W
HDN 065 038/075 042/076 035/066 035/072 039/068 036/059
2/W 00/B 03/W 20/B 00/U 03/W 22/W
MLS 059 041/071 044/074 035/063 037/069 038/067 037/057
1/E 10/B 03/W 20/B 00/U 02/W 22/W
4BQ 059 039/071 040/077 036/064 036/070 039/069 035/058
2/W 20/B 03/W 30/B 00/U 01/B 21/N
BHK 052 035/065 039/073 035/061 033/066 037/066 035/054
1/M 30/E 02/W 30/U 00/U 02/W 31/N
SHR 060 038/070 039/077 035/065 035/070 038/069 034/055
2/W 10/B 03/W 31/B 00/B 02/W 32/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
610 AM CDT THU MAR 26 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CDT THU MAR 26 2015
TODAY AND TONIGHT...THE DISTURBANCE ACROSS THE NRN HIGH PLAINS...WRN
SD/ND AND ERN MT...SHOULD MOVE SOUTHEAST THROUGH VALENTINE AND
ONEILL AREAS THIS MORNING PRODUCING SCATTERED RAIN AND SNOW SHOWERS.
SOME ISOLATED INSTABILITY SHOWERS MAY ALSO DEVELOP FARTHER WEST AND
SOUTH.
A SECOND DISTURBANCE ACROSS WRN MT WILL BE AFFECTING WRN NEB TONIGHT
AS A WARM FRONT DEVELOPS. THE MODELS ARE VERY BULLISH WITH THE PCPN
ENCOMPASSING A LARGE PORTION OF THE FCST AREA GIVEN THE VERY DRY
CONDITIONS OF THE PAST 6-7 WEEKS. BUT WE WILL RUN A MODEL BLEND FOR
ISOLATED TO SCATTERED RAIN OR SNOW SHOWERS. LESS THAN 1/10 OF AN
INCH OF RAIN IS EXPECTED ACROSS ALL AFFECTED AREAS.
ARCTIC HIGH PRESSURE ACROSS MANITOBA WILL MOVE SOUTH TODAY TO NEAR
WINNIPEG AND THEN INTO SRN ONTARIO BY FRIDAY MORNING. THIS WILL
ALLOW FOR COLD AIR TO BACK INTO THE FCST AREA. THIS SHOULD PRODUCE
HIGHS IN THE 40S WITH RAIN OR SNOW SHOWERS FROM VALENTINE TO ONEILL.
50S TO NEAR 60 ARE EXPECTED ELSEWHERE. MODEL PLUMES SHOW STRONG
NORTHWEST WINDS AHEAD OF THE COLD FRONT ACROSS SWRN NEB...20 TO 30
MPH WINDS.
A WARM FRONT SHOULD DEVELOP TONIGHT ACROSS WRN NEB AS THE HIGH MOVES
EAST INTO ONTARIO. LOWS IN THE 20S TO NEAR 30 ARE EXPECTED WITH
SIGNIFICANT CLOUD COVER HOLDING UP THE RADIATIONAL COOLING.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 322 AM CDT THU MAR 26 2015
FRIDAY MORNING BEGINS WITH INHERITED POPS FROM THE PREVIOUS
PERIOD. AGAIN...NOT EXPECTING MUCH IN THE WAY OF COVERAGE OR QPF
AS MOISTURE IS PRETTY SCARCE IN THE BOUNDARY LAYER. ANY PRECIP
ACTIVITY SHOULD BE OUT OF THE CWA BY MID TO LATE MORNING. HIGHS ON
FRIDAY WILL VARY GREATLY FROM WEST TO EAST AS SHORTWAVE RIDGING
BUILDS ALOFT AND A WARM FRONT SLOWLY MOVES INTO THE AREA. BEHIND
THE FRONT WINDS WILL BE WEST/NORTHWEST AND UNIDIRECTIONAL THROUGH
MOST OF THE TROPOSPHERE. THIS WILL PROMOTE DEEP MIXING AND HIGHS
INTO THE MID 60S TO NEAR 70 DESPITE PARTLY TO MOSTLY CLOUDY SKIES.
FURTHER EAST INTO CENTRAL NEBRASKA TEMPERATURES WILL REMAIN COOLER
AS H85 REMAIN AROUND 0C TO 5C.
A ROBUST PV MAX MOVES SOUTHEAST OUT OF CANADA ON SATURDAY AND
FLATTENS THE RIDGE. THE ATTENDANT SFC LOW REMAINS WELL NORTH OF THE
AREA. HOWEVER IT WILL PUSH A DRYLINE INTO THE CWA AS HEIGHTS FALL
AND WINDS BECOME WEST/SOUTHWEST...ADVECTING A DRIER AIR MASS OFF THE
FRONT RANGE. THE DRYLINE LOOKS TO SET UP NEAR HWY 83 DURING THE
AFTERNOON. GFS IS FURTHER WEST WITH THE DRY LINE THAN THE OTHER
MODELS AT THIS TIME...HOWEVER GIVEN THE ANTECEDENT DRY CONDITIONS WILL
GO AHEAD AND FAVOR A MORE AGGRESSIVE SOLUTION. THE EASTWARD
PROGRESS OF THE DRYLINE IS IMPORTANT DUE TO THE POTENTIAL
IMPLICATIONS ON LOCAL FIRE WEATHER CONDITIONS DURING THE
AFTERNOON AND EARLY EVENING HOURS.
A COLD FRONT OVERTAKES THE DRYLINE SATURDAY NIGHT AND PUSHES THROUGH
THE CWA. GUSTY WINDS BEHIND THE FRONT WILL LIKELY KEEP THE BL WELL
MIXED AND RELATIVELY MILD THROUGH THE OVERNIGHT HOURS. CROSS
SECTIONS SHOW UPRIGHT INSTABILITY ALONG THE FRONT...AND THE GFS EVEN
HAS SLIGHTLY NEGATIVE LI/S. A FEW MODELS SHOW LIGHT QPF OVER
WESTERN NEBRASKA...HOWEVER STILL NOT CONFIDENT ENOUGH TO PUT ANY POPS IN
THE FORECAST AT THIS TIME GIVEN THE MOISTURE STARVED SETUP.
WARM AND DRY CONDITIONS CONTINUE INTO THE FIRST HALF OF NEXT WEEK.
WARMEST DAY WILL BE TUESDAY AS H85 TEMPS INCREASE TO 18C TO
20C IN ADVANCE OF THE NEXT PV MAX EJECTING SOUTHEAST OUT OF CANADA.
PROGRESSIVE SPLIT FLOW PATTERN ALOFT WILL LIKELY KEEP ANY
APPRECIABLE LOW LEVEL MOISTURE TO OUR SOUTH AND EAST...SO HIGH FIRE
DANGER WILL BE A CONCERN SUNDAY THROUGH TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 610 AM CDT THU MAR 26 2015
THE MODEL CONSENSUS INCLUDING THE RAP AND HRRR SUGGEST AN AREA OF
RAIN WILL SWEEP SOUTH THROUGH KVTN-KANW-KONL THIS MORNING AND
AFTN. THE SREF SUGGESTS MVFR CIGS WITH THE RAIN AND LOCAL IFR IN
SOME HEAVIER SHOWERS.
TONIGHT...AN AREA OF MVFR CIGS IN RAIN/SNOW IS SUGGESTED ACROSS
WRN NEB...PERHAPS AS FAR SOUTH AS KOGA/KLBF...ASSOCIATED WITH A WARM
FRONT AND A DISTURBANCE ACROSS WRN MT THIS MORNING. THE WARM FRONT
AND LOW CIGS SHOULD PROGRESS SLOWLY EAST THROUGH WRN NEB
OVERNIGHT AND BE LOCATED NEAR HIGHWAY 83 BY FRIDAY MORNING.
&&
.FIRE WEATHER...
ISSUED AT 322 AM CDT THU MAR 26 2015
SATURDAY COULD BE AN OPPORTUNITY FOR CRITICAL FIRE
DANGER WEST OF HIGHWAY 83. A DRY LINE BULGE SHOULD SWEEP EAST IN THE
AFTN SENDING RH VALUES INTO THE LOWER TEENS. WINDS ALOFT AT 700 MB
INCREASE TO 30 KTS IN THE NAM AND GFS SUGGESTING WIND GUSTS TO 25 OR
30 MPH. ERRORS IN MODEL TIMING...THE MODELS COULD BE TOO FAST...
MAKE THIS FORECAST UNCERTAIN AT THIS TIME. A POWERFUL COLD FRONT
SHOULD BE DROPPING THROUGH THE NRN HIGH PLAINS DURING THE AFTN WHICH
WILL SUPPORT THE STRONG WEST WINDS ACROSS WRN NEB SATURDAY AFTN.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...MARTIN
AVIATION...CDC
FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
642 AM EDT THU MAR 26 2015
.SYNOPSIS...
TEMPERATURES WILL REMAIN ABOVE NORMAL TODAY AHEAD OF A STRONG
COLD FRONT. SHARP COOLING WILL ARRIVE FRIDAY AS THE FRONT SWEEPS
THROUGH...WITH LOWS IN THE 30S THIS WEEKEND...AND POSSIBLY NEAR
FREEZING SUNDAY MORNING. TEMPERATURES HOWEVER WILL REBOUND QUICKLY
TO NEAR SEASONABLE LEVELS EARLY NEXT WEEK...AS AN UPPER TROUGH
MOVES EAST OF THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 645 AM THURSDAY...RADAR SHOWS A LARGE CLUSTER OF SHOWERS AND
EMBEDDED T-STORMS SOUTH OF CAPE FEAR...WITH LIGHTER SHOWERS
EXTENDING NW ACROSS NORTHERN HORRY COUNTY AND THROUGH WHITEVILLE
AND ELIZABETHTOWN. LINEAR EXTRAPOLATION BRINGS THE OFFSHORE ACTIVITY
ACROSS SE NORTH CAROLINA BETWEEN 12Z/8 AM EDT AND 15Z/11 AM EDT.
POPS REMAIN IN THE 80-100 PERCENT RANGE WITH UP TO AN ADDITIONAL
2/3RDS OF AN INCH OF RAIN FORECAST. THE 07Z HRRR APPEARS TO HAVE A
GOOD HANDLE ON THE SITUATION AND WAS THE BASIS FOR THIS UPDATE.
DISCUSSION FROM 300 AM FOLLOWS...
A WARM FRONT BACKING INLAND FROM THE COAST IS PRODUCING LOW
STRATUS CLOUDS NEAR AND WEST OF I-95...WHILE JUST EAST OF THE
FRONT A LINE OF SHOWERS AND EMBEDDED THUNDERSTORMS WILL MOVE
NORTHEASTWARD TOWARD COASTAL NORTH CAROLINA. INDIVIDUAL CONVECTIVE
CELLS ARE MOVING NORTHWARD BUT NET LINE MOTION SHOULD PICK UP A
SLOW EASTWARD MOTION SHORTLY...STEERED BY THE 700-500 MB FLOW
WHICH IS STRENGTHENING OUT AHEAD OF A SHORTWAVE TROUGH DIGGING
INTO THE MID-MISSISSIPPI VALLEY. HIGH-RESOLUTION MODELS LIKE THE
HRRR AND THE NSSL WRF SHOW THIS ACTIVITY MERGING INTO A HEFTY LINE
AS IT REACHES THE WILMINGTON METRO AREA AFTER DAYBREAK. MID-LEVEL
LAPSE RATES ARE IMPRESSIVELY STEEP AND GIVEN THE TRAINING NATURE
OF THE STORMS WE COULD SEE LOCALLY HEAVY RAINFALL.
ONCE THIS CONVECTIVE ACTIVITY CLEARS THE COAST BY 10 AM OR
SO...DOWNWARD MOTION THROUGH THE MID-LEVELS SHOULD LEAD TO CLEARING
SKIES AND A LULL IN CONVECTION FOR THE REMAINDER OF THE DAY. IN FACT
THERE SHOULD BE SO MUCH SUNSHINE I AM FORECASTING HIGH TEMPERATURES
A DEGREE ABOVE THE WARMEST MODEL OR MOS I COULD FIND...LOWER 80S
INLAND WITH MID TO UPPER 70S AT THE COAST. THE BEACHES WILL RUN
SEVERAL DEGREES COOLER WITH SOUTH WINDS ADVECTING IN CHILLY AIR OFF
THE NEARSHORE WATERS. HIGH-RES MODELS SHOW A SMATTERING OF SHOWERS
DEVELOPING IN THE HEAT OF THE DAY WELL INLAND BUT THIS MIGHT BE
OPTIMISTIC GIVEN THE VERY DRY AIR ANTICIPATED TO BE IN PLACE AT THE
TOP OF THE BOUNDARY LAYER.
AS THE UPPER TROUGH APPROACHES TONIGHT AND ANOTHER SLUG OF DEEP
MOISTURE ARRIVES FROM THE GULF...CONVECTIVE ACTIVITY SHOULD INCREASE
IN COVERAGE LATE IN THE EVENING AND ESPECIALLY OVERNIGHT. SEVERE
WEATHER POTENTIAL APPEARS QUITE LOW GIVEN LACK OF SURFACE-BASED
INSTABILITY AND INCREASINGLY UNIDIRECTIONAL WIND FIELDS. MY FORECAST
LOWS ARE WELL ABOVE MOS AND CLOSE TO A RAW MODEL BLEND WITH LOWER TO
MID 60S FOR MOST AREAS. THE SURFACE COLD FRONT WILL SHOW UP WEST OF
I-95 SHORTLY AFTER DAYBREAK FRIDAY...AND I PENCILED IN A NARROW ZONE
OF COOLER FORECAST LOWS HERE EXPECTING COLD ADVECTION TO DEVELOP.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...A STRONG COLD FRONT WILL BE MOVING THROUGH
THE AREA AT THE BEGINNING OF THE PERIOD. LOW LEVEL CONVERGENCE AS
WELL AS MID LEVEL HEIGHT FALLS WARRANT LIKELY POPS TROUGH THE
EARLY AFTERNOON HOURS WEST TO EAST. ADEQUATE MOISTURE AND
CERTAINLY ENOUGH DYNAMICS AS THE POWERFUL VORT ASSOCIATED WITH THE
MID LEVEL TROUGH ROTATES ACROSS WARRANTS HOLDING ON TO POPS AND
DRIZZLE FOR FRIDAY AFTERNOON AND NIGHT. MAINTAINED THE MIX OF SNOW
SHOWERS FOR A FEW HOURS EARLY SATURDAY BUT ANY APPEARANCE OF
FLAKES WILL BE FLEETING. COLD AIR ADVECTION WITH CLEARING SKIES
WILL PREVAIL SATURDAY AS HIGH PRESSURE BUILDS IN FROM THE
NORTHWEST.
THE FOCUS THEN SHIFTS TO SUNDAY MORNING LOWS AS MODELS AND GUIDANCE
REMAIN CONSISTENT ON THE AREA OF HIGH PRESSURE BEING CENTERED ALONG
THE APPALACHIANS. MEX NUMBERS ARE ALL BUT UNCHANGED WITH 30 IN
WILMINGTON AND 28 IN LBT. THE CONSISTENCY OF THE HIGHS PLACEMENT
OVER THE APPALACHIANS GIVES SOME POSSIBILITY OF WINDS REMAINING UP
JUST ENOUGH TO PREVENT A DESTRUCTIVE FREEZE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...A RELATIVELY UNEVENTFUL EXTENDED PERIOD
AS THE MID LEVEL PATTERN FLATTENS. A SUBTLE TROUGH WILL PUSH A
FRONT THROUGH THE AREA TUESDAY. THE LATEST GFS HAS THIS OCCURRING
MUCH FASTER AND WETTER THAN THE ECMWF BUT WILL CONTINUE TO FAVOR
THE SLOWER AND DRIER SOLUTION FAVORED BY WPC. THIS FEATURE WILL
SERVE TO BRIEFLY PUT A HOLD ON THE WARMUP THAT WILL PICK UP IN
EARNEST LATE IN THE PERIOD. SUNDAY WILL CONTINUE TO BE RATHER COLD
WITH HIGHS IN THE 50S AND LOWS MONDAY MORNING DIPPING INTO THE
UPPER 30S. MONDAY AND TUESDAY WILL SEE 60S AND 40S. WEDNESDAY WILL
SEE A NICE WARMUP WITH HIGHS REACHING THE 70S. NO POPS THROUGH THE
PERIOD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 06Z...ANTICIPATE MVFR/IFR OVERNIGHT INTO THE MORNING HOURS ON
DUE TO LOW CIGS...RADAR SHOWS EXPANDING SHOWERS MOVING ONSHORE
AND NORTHWARD THROUGH EASTERN SC. THIS ACTIVITY WILL LARGELY
SIDESTEP FLO TO THE EAST...AFFECTING MYR/CRE AND LBT THROUGH 10Z.
AFTER 10Z IT WILL SHIFT TOWARD ILM WITH CONTINUED UPSCALE
CONVECTIVE DEVELOPMENT POSSIBLE. LOW STRATUS WEST OF THE SHOWERS
WILL BECOME WIDESPREAD ACROSS FLO AND LBT BETWEEN 07-08Z...WITH
LOWER CHANCES OF IFR CIGS DEVELOPING AT MYR/CRE CLOSER TO
DAYBREAK.
AFTER DAYBREAK...LOW CLOUDS MAINLY INLAND WILL LIFT IN THE 13-15Z
TIMEFRAME. CONVECTION NEAR ILM SHOULD PUSH OFFSHORE BY 15Z. DRY
MID-LEVEL AIR SHOULD PRODUCE A LULL IN SHOWER ACTIVITY LASTING
THROUGH MUCH OF THE DAYLIGHT HOURS. SFC WINDS WILL INCREASE TO
12G20KT.
EXTENDED OUTLOOK...MVFR/IFR POSSIBLE ON FRIDAY AND SATURDAY WITH
SHRA...BECOMING VFR LATER SATURDAY. ISOLATED SHOWERS ON MONDAY.
OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 645 AM THURSDAY...BASED ON BUOY OBSERVATIONS I HAVE
INCREASED FORECAST SEA HEIGHTS FOR THIS MORNING BY ABOUT A FOOT
FOR THE NORTH CAROLINA WATERS...WITH LITTLE CHANGE ACROSS SC. A
LARGE CLUSTER OF SHOWERS AND EMBEDDED T-STORMS SOUTH OF CAPE FEAR
IS MOVING NORTHWARD AND WILL MOVE ONSHORE IN LESS THAN TWO HOURS.
MARINERS WILL NEED TO PLAN FOR HEAVY RAIN...GUSTY WINDS AND THE
POTENTIAL FOR LIGHTNING THIS MORNING. DISCUSSION FROM 300 AM
FOLLOWS...
A RATHER STRONG COLD FRONT JUST NOW REACHING THE LOWER
MISSISSIPPI VALLEY WILL MOVE EASTWARD AND APPROACH THE EASTERN
CAROLINAS LATE TONIGHT. THE BOUNDARY WILL NOT REACH THE WATER
UNTIL SEVERAL HOURS AFTER DAYBREAK FRIDAY. THIS MEANS SOUTH WINDS
WILL CONTINUE TODAY AND TONIGHT.
THERE ARE TWO PERIODS OF PARTICULARLY STRONG WINDS TO DEAL WITH. THE
FIRST IS ONGOING NOW AS A WEAK AREA OF LOW PRESSURE MOVES NORTH
ALONG A WARM FRONT ACROSS THE INTERIOR EASTERN CAROLINAS. THIS LOW
IS HELPING CREATE A LINE OF SHOWERS WHICH WILL MOVE ACROSS THE
WATERS DURING THE MORNING HOURS. UNSTABLE CONDITIONS ALOFT COULD
ALLOW THESE SHOWERS TO STRENGTHEN INTO THUNDERSTORMS AS SEVERAL OF
THE HIGH-RESOLUTION MODELS SUGGEST. ALTHOUGH WINDS AWAY FROM SHORE
WILL GO INTO A LULL THIS AFTERNOON...A SEABREEZE NEARSHORE SHOULD
HOLD WINDS NEAR 15 KNOTS. TONIGHT SOUTH WINDS WILL AGAIN INCREASE
AHEAD OF THE INCOMING COLD FRONT.
WITH ONSHORE WIND DIRECTIONS...LARGE SEAS ARE BEING DIRECTED FROM
WELL OFFSHORE INTO THE NEARSHORE WATERS. RECENT REPORTS INCLUDE 5
FEET AT THE NEARSHORE WRIGHTSVILLE BEACH BUOY...AND 4 FEET AT THE
"HARBOR" BUOY SOUTH OF SOUTHPORT. THESE SEAS COULD BUILD ANOTHER
FOOT THIS MORNING BEFORE THE AFTERNOON LULL. A SMALL CRAFT ADVISORY
HAS BEEN ISSUED FOR THE NC WATERS FOR THE POTENTIAL OF 6 FOOT
SEAS.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...A COLD FRONT WILL MOVE ACROSS THE WATERS EARLY
FRIDAY MORNING SHIFTING THE WINDS FROM SOUTHWEST TO NORTHWEST. A
SMALL CRAFT ADVISORY WILL CONTINUE THROUGH MOST OF THE MORNING HOURS
DUE TO RESIDUAL HIGHER SEAS FROM THE PREFRONTAL FLOW. THE NORTHWEST
FLOW WILL WILL BE ON THE ORDER OF 15-20 KNOTS. THIS WILL PERSIST FOR
SOME TIME AND ONLY BEGIN TO WEAKEN SATURDAY AFTERNOON. THE HIGHER
SEAS...3-5 FEET WILL BE RELEGATED TO THE OUTERMOST WATERS DURING
THIS TIME. SEAS DROP TO 2-3 FEET BY SUNDAY MORNING ALONG WITH THE
EVER WEAKENING WINDS.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 300 AM THURSDAY...HIGH PRESSURE WILL BE DRIFTING OVERHEAD SUNDAY
RESULTING IN LIGHT WINDS FIELDS ACROSS THE WATERS.EXPECT NORTHEAST
WINDS OF 10-15 KNOTS INITIALLY BACKING OFF TO TEN KNOTS OR LESS BY
SUNSET. A RETURN FLOW OF SOUTH TO SOUTHWEST WINDS WITH SPEEDS OF 15-
20 KNOTS DEVELOPS MONDAY. SIGNIFICANT SEAS OF 2-4 FEET CAN BE
EXPECTED THROUGH THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT FRIDAY FOR AMZ250-252.
&&
$$
SYNOPSIS...SHK
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...TRA/SGL
MARINE...
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
931 AM EDT THU MAR 26 2015
.SYNOPSIS...
LOW PRESSURE LIFTS NORTHEAST THROUGH UPPER OHIO VALLEY THIS MORNING.
STRONG COLD FRONT CROSSES THIS AFTERNOON. MUCH COLDER AIR DOMINATES
LATE TONIGHT THROUGH SUNDAY MORNING.
&&
.NEAR TERM /THROUGH TONIGHT/...
930 AM UPDATE...
ADJUSTED POPS FOR LEADING EDGE OF RAIN IN THE MIDDLE OHIO VALLEY
THIS MORNING. FCST OTHERWISE ON TRACK WITH WAVY FRONT NEARLY
STATIONARY NEAR THE OHIO RIVER.
PREV DISCN...
LEANED FAIRLY HEAVILY ON THE HRRR INTO THIS AFTERNOON. SURFACE
BOUNDARY HAS DEVELOPED ACROSS OHIO...AND IS APPARENT IN THE OBS.
KZZV HAS A SE WIND WHILE KOSU IS NORTHERLY. THIS PUTS THE BOUNDARY
JUST TO THE NW OF PERRY COUNTY. A SOMEWHAT ELONGATED SURFACE WAVE
IS MOVING UP THE FRONT...CURRENTLY IN WESTERN KY/TN. EXPECT THIS
WAVE TO CROSS WESTERN CWA THIS MORNING...THEN AS IT CONTINUES TO
THE NE IT WILL DRAG COLD FRONT THROUGH THIS AFTERNOON AND EVENING.
HAVE HIGHEST POPS JUST BEHIND THE FRONT. PREVIOUS FORECAST TIMING
STILL LOOKS PRETTY GOOD...SO NO SIGNIFICANT CHANGES THERE. HAVE
THE FRONT CROSSING THE OHIO RIVER 17Z-18Z. NEAR THE I-79 CORRIDOR
FROM CRW TO CKB AROUND 19Z- 20Z. MAKING IT INTO THE MOUNTAINS 21Z-
22Z...AND THEN HEADED EAST OF CWA BY 00Z. DID TIGHTEN UP THE POP
GRADIENT...AND HAVE DRY POPS MAKING IT TO THE OHIO RIVER BY THE
END OF NEAR TERM. HAVE A PERIOD OF THUNDER POSSIBLE ALONG THE
FRONT. WENT WITH NON-DIURNAL TEMPS ACROSS THE WEST...AS
TEMPERATURES BEGIN TO COOL BEHIND THE FRONT THIS AFTERNOON. BUMPED
UP HIGHS ACROSS THE EAST A LITTLE WITH GOOD SOUTHERLY FLOW AND A
TIGHTER POP GRADIENT KEEPING THINGS DRY THERE A BIT LONGER...PLUS
MANY HAVE ONLY COOLED INTO THE LOW TO MID 50S SO FAR EARLY THIS
MORNING.
COLD AIR CONTINUES TO WORK IN BEHIND THE FRONT TONIGHT. HAVE RAIN
CHANGING OVER TO SNOW...WITH POSSIBLY A LITTLE SLEET IN SOME
LOCATIONS RIGHT AROUND THE TRANSITION TIME. ENDED UP WITH ABOUT AN
INCH OF SNOW BY 12Z AT THE HIGHER ELEVATIONS OF THE NORTHERN
MOUNTAINS...WITH A COATING TO HALF INCH IN MOUNTAIN VALLEYS ACROSS
THE EASTERN CWA.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
OLD MAN WINTER`S ENCORE APPEARANCE LINGERS INTO SUNDAY MORNING.
NO BIG CHANGES MADE TO OUR FORECAST FOR THIS SHORT TERM. THE BOARD
500 MB TROF SHARPENS WITH ITS AXIS NOT PASSING UNTIL 08Z TO 12Z
SATURDAY. THE 850 MB THERMAL TROF HANGS OVER US INTO THE DAY ON
SATURDAY...BUT WITH TEMPERATURES MODERATING A FEW DEGREES ON
SATURDAY. THE COLDEST 850 MB TEMPERATURES ARE FRIDAY NIGHT TO 12Z
SATURDAY...WITH BEST CRYSTAL GROWTH TEMPERATURES IN THE LINGERING
LOW LEVEL MOISTURE. SO CONTINUE TO HAVE POPS HIGHER THAN BOTH NAM
AND GFS MOS GUIDANCE FOR THE WV MOUNTAIN COUNTIES.
IN TERMS OF SHOWER COVERAGE...STILL THINKING A SEMI LULL IN PCPN
COVERAGE 12Z TO 16Z FRIDAY...THEN INCREASING FOR FRIDAY AFTERNOON
AND FRIDAY EVENING...WITH BEST CHANCE OF GROUND WHITENING IN THE
LOWLANDS LATE FRIDAY AFTERNOON OR FRIDAY EVENING. HAVE A FEW INCHES
OF SNOW ACCUMULATION OVER THE CENTRAL WV MOUNTAINS. HARD TO TELL
HOW MUCH THE SNOW SHOWERS WILL DIURNALLY DECREASE OVERNIGHT FRIDAY
NIGHT.
AS WE MENTIONED YESTERDAY...STILL THINKING NOT SOLID OVERCAST ON
FRIDAY...BUT CELLULAR FOR THIS TIME OF THE YEAR. SO STILL TRYING TO
LEAK THE LOWLAND TEMPERATURES UP INTO THE LOWER 40S BETWEEN SHOWERS.
YET...WITH THE COLD AIR ALOFT...LEFT THE POSSIBLE OF SNOW OR RAIN
SHOWERS EVEN WITH TEMPERATURES AROUND 40 DEGREES.
HIGH PRESSURE AND A CLEARER NIGHT EXPECTED FOR SATURDAY NIGHT/SUNDAY
MORNING. FORECAST TEMPERATURES NEAR RECORD LOWS FOR MARCH 29TH.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ROLLER COASTER RIDE IN THE TEMP DEPARTMENT TO CONTINUE THRU THE
EXTENDED PERIODS. SURFACE HIGH AND A VERY DRY AIRMASS WILL ALLOW
FOR IDEAL RADIATIONAL COOLING SATURDAY NIGHT WITH MANY PLACES
DIPPING INTO THE TEENS. TRIED TO HIT THE TYPICAL COLD SPOTS HARD
WHILE KEEPING AREAS ALONG BIG RIVERS A FEW DEGREES HIGHER THAN
GUIDANCE SUGGESTS. A NICE REBOUND WILL BE REALIZED ON SUNDAY AMID WAA
ALOFT ON STRENGTHENING SW FLOW. A FAST MOVING COLD FRONT WILL
SLIDE THRU SUNDAY NIGHT WITH A CHANCE FOR SHOWERS. A WAVE MAY
DEVELOP IN THE TN VALLEY ON MONDAY WHICH WOULD KEEP THE RAIN
THREAT GOING ACROSS SW VA AND SE WV. TEMPS WILL COME BACK DOWN
BEHIND THE FRONT AS NW FLOW ALOFT BECOMES ESTABLISHED BEHIND A
CLIPPER SYSTEM EARLY TUESDAY...WITH A SMALL CHANCE FOR A SHOWER
AND SNOW SHOWER FOR THE N MOUNTAINS. UPPER HEIGHTS WILL QUICKLY
REBOUND MIDWEEK WITH DECENT WAA CRANKING ONCE AGAIN...AHEAD OF THE
NEXT FRONT. AS A RESULT...TEMPS SHOULD SPIKE INTO THE 70S ONCE
AGAIN LONG ABOUT WEDNESDAY.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS CURRENTLY IN PLACE. PRECIPITATION IN SE OHIO ALONG
A NEARLY STATIONARY SURFACE BOUNDARY. AS AN ELONGATES SURFACE LOW
MOVES UP THE BOUNDARY THIS PRECIPITATION WILL EXPAND. AS THE LOW
PASSES... BOUNDARY WILL SINK SOUTHWEST AS A COLD FRONT THIS
AFTERNOON. HAVE THUNDER POSSIBLE RIGHT ALONG THE FRONT...WITH
MVFR IN RAIN FOR SEVERAL HOURS BEHIND THE FRONT. COULD EVEN GET
SOME IFR IN STRONGER SHOWERS/STORMS...BUT HARD TO TIME ANYTHING AT
THIS POINT. WINDS WILL INCREASE OUT OF THE SOUTH AHEAD OF THE
FRONT...SWITCHING TO GUSTY NW BEHIND THE FRONT. AS COLD AIR SURGES
IN BEHIND THE FRONT...WILL GET CHANGEOVER TO SNOW.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF RESTRICTIONS IN CLOUDS AND
PRECIPITATION COULD VARY. MAY GET IFR IN STRONGER SHOWERS/STORMS
AND ALSO TONIGHT IN LOW CLOUDS AND MOUNTAIN SNOW SHOWERS.
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 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H M H H H H
BKW CONSISTENCY L L L H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H M M
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 12Z FRIDAY...
IFR POSSIBLE INTO FRIDAY ACROSS NORTHERN WV AND DOWN THROUGH THE
MOUNTAINS IN MIXED RAIN AND SNOW SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/MZ/30
NEAR TERM...TRM/MZ
SHORT TERM...KTB
LONG TERM...30
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
652 AM EDT THU MAR 26 2015
.SYNOPSIS...
LOW PRESSURE LIFTS NORTHEAST THROUGH UPPER OHIO VALLEY THIS MORNING.
STRONG COLD FRONT CROSSES THIS AFTERNOON. MUCH COLDER AIR DOMINATES
LATE TONIGHT THROUGH SUNDAY MORNING.
&&
.NEAR TERM /THROUGH TONIGHT/...
LEANED FAIRLY HEAVILY ON THE HRRR INTO THIS AFTERNOON. SURFACE
BOUNDARY HAS DEVELOPED ACROSS OHIO...AND IS APPARENT IN THE OBS.
KZZV HAS A SE WIND WHILE KOSU IS NORTHERLY. THIS PUTS THE BOUNDARY
JUST TO THE NW OF PERRY COUNTY. A SOMEWHAT ELONGATED SURFACE WAVE IS
MOVING UP THE FRONT...CURRENTLY IN WESTERN KY/TN. EXPECT THIS WAVE
TO CROSS WESTERN CWA THIS MORNING...THEN AS IT CONTINUES TO THE NE
IT WILL DRAG COLD FRONT THROUGH THIS AFTERNOON AND EVENING. HAVE
HIGHEST POPS JUST BEHIND THE FRONT. PREVIOUS FORECAST TIMING STILL
LOOKS PRETTY GOOD...SO NO SIGNIFICANT CHANGES THERE. HAVE THE FRONT
CROSSING THE OHIO RIVER 17Z-18Z. NEAR THE I-79 CORRIDOR FROM CRW TO
CKB AROUND 19Z-20Z. MAKING IT INTO THE MOUNTAINS 21Z-22Z...AND THEN
HEADED EAST OF CWA BY 00Z. DID TIGHTEN UP THE POP GRADIENT...AND
HAVE DRY POPS MAKING IT TO THE OHIO RIVER BY THE END OF NEAR TERM.
HAVE A PERIOD OF THUNDER POSSIBLE ALONG THE FRONT. WENT WITH
NON-DIURNAL TEMPS ACROSS THE WEST...AS TEMPERATURES BEGIN TO COOL
BEHIND THE FRONT THIS AFTERNOON. BUMPED UP HIGHS ACROSS THE EAST A
LITTLE WITH GOOD SOUTHERLY FLOW AND A TIGHTER POP GRADIENT KEEPING
THINGS DRY THERE A BIT LONGER...PLUS MANY HAVE ONLY COOLED INTO THE LOW
TO MID 50S SO FAR EARLY THIS MORNING.
COLD AIR CONTINUES TO WORK IN BEHIND THE FRONT TONIGHT. HAVE RAIN
CHANGING OVER TO SNOW...WITH POSSIBLY A LITTLE SLEET IN SOME
LOCATIONS RIGHT AROUND THE TRANSITION TIME. ENDED UP WITH ABOUT AN
INCH OF SNOW BY 12Z AT THE HIGHER ELEVATIONS OF THE NORTHERN
MOUNTAINS...WITH A COATING TO HALF INCH IN MOUNTAIN VALLEYS ACROSS
THE EASTERN CWA.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
OLD MAN WINTER`S ENCORE APPEARANCE LINGERS INTO SUNDAY MORNING.
NO BIG CHANGES MADE TO OUR FORECAST FOR THIS SHORT TERM. THE BOARD
500 MB TROF SHARPENS WITH ITS AXIS NOT PASSING UNTIL 08Z TO 12Z
SATURDAY. THE 850 MB THERMAL TROF HANGS OVER US INTO THE DAY ON
SATURDAY...BUT WITH TEMPERATURES MODERATING A FEW DEGREES ON
SATURDAY. THE COLDEST 850 MB TEMPERATURES ARE FRIDAY NIGHT TO 12Z
SATURDAY...WITH BEST CRYSTAL GROWTH TEMPERATURES IN THE LINGERING
LOW LEVEL MOISTURE. SO CONTINUE TO HAVE POPS HIGHER THAN BOTH NAM
AND GFS MOS GUIDANCE FOR THE WV MOUNTAIN COUNTIES.
IN TERMS OF SHOWER COVERAGE...STILL THINKING A SEMI LULL IN PCPN
COVERAGE 12Z TO 16Z FRIDAY...THEN INCREASING FOR FRIDAY AFTERNOON
AND FRIDAY EVENING...WITH BEST CHANCE OF GROUND WHITENING IN THE
LOWLANDS LATE FRIDAY AFTERNOON OR FRIDAY EVENING. HAVE A FEW INCHES
OF SNOW ACCUMULATION OVER THE CENTRAL WV MOUNTAINS. HARD TO TELL
HOW MUCH THE SNOW SHOWERS WILL DIURNALLY DECREASE OVERNIGHT FRIDAY
NIGHT.
AS WE MENTIONED YESTERDAY...STILL THINKING NOT SOLID OVERCAST ON
FRIDAY...BUT CELLULAR FOR THIS TIME OF THE YEAR. SO STILL TRYING TO
LEAK THE LOWLAND TEMPERATURES UP INTO THE LOWER 40S BETWEEN SHOWERS.
YET...WITH THE COLD AIR ALOFT...LEFT THE POSSIBLE OF SNOW OR RAIN
SHOWERS EVEN WITH TEMPERATURES AROUND 40 DEGREES.
HIGH PRESSURE AND A CLEARER NIGHT EXPECTED FOR SATURDAY NIGHT/SUNDAY
MORNING. FORECAST TEMPERATURES NEAR RECORD LOWS FOR MARCH 29TH.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ROLLER COASTER RIDE IN THE TEMP DEPARTMENT TO CONTINUE THRU THE
EXTENDED PERIODS. SURFACE HIGH AND A VERY DRY AIRMASS WILL ALLOW
FOR IDEAL RADIATIONAL COOLING SATURDAY NIGHT WITH MANY PLACES
DIPPING INTO THE TEENS. TRIED TO HIT THE TYPICAL COLD SPOTS HARD
WHILE KEEPING AREAS ALONG BIG RIVERS A FEW DEGREES HIGHER THAN
GUIDANCE SUGGESTS. A NICE REBOUND WILL BE REALIZED ON SUNDAY AMID WAA
ALOFT ON STRENGTHENING SW FLOW. A FAST MOVING COLD FRONT WILL
SLIDE THRU SUNDAY NIGHT WITH A CHANCE FOR SHOWERS. A WAVE MAY
DEVELOP IN THE TN VALLEY ON MONDAY WHICH WOULD KEEP THE RAIN
THREAT GOING ACROSS SW VA AND SE WV. TEMPS WILL COME BACK DOWN
BEHIND THE FRONT AS NW FLOW ALOFT BECOMES ESTABLISHED BEHIND A
CLIPPER SYSTEM EARLY TUESDAY...WITH A SMALL CHANCE FOR A SHOWER
AND SNOW SHOWER FOR THE N MOUNTAINS. UPPER HEIGHTS WILL QUICKLY
REBOUND MIDWEEK WITH DECENT WAA CRANKING ONCE AGAIN...AHEAD OF THE
NEXT FRONT. AS A RESULT...TEMPS SHOULD SPIKE INTO THE 70S ONCE
AGAIN LONG ABOUT WEDNESDAY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS CURRENTLY IN PLACE. PRECIPITATION IN SE OHIO ALONG
A NEARLY STATIONARY SURFACE BOUNDARY. AS AN ELONGATES SURFACE LOW
MOVES UP THE BOUNDARY THIS PRECIPITATION WILL EXPAND. AS THE LOW
PASSES... BOUNDARY WILL SINK SOUTHWEST AS A COLD FRONT THIS
AFTERNOON. HAVE THUNDER POSSIBLE RIGHT ALONG THE FRONT...WITH
MVFR IN RAIN FOR SEVERAL HOURS BEHIND THE FRONT. COULD EVEN GET
SOME IFR IN STRONGER SHOWERS/STORMS...BUT HARD TO TIME ANYTHING AT
THIS POINT. WINDS WILL INCREASE OUT OF THE SOUTH AHEAD OF THE
FRONT...SWITCHING TO GUSTY NW BEHIND THE FRONT. AS COLD AIR SURGES
IN BEHIND THE FRONT...WILL GET CHANGEOVER TO SNOW.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: TIMING OF RESTRICTIONS IN CLOUDS AND
PRECIPITATION COULD VARY. MAY GET IFR IN STRONGER SHOWERS/STORMS
AND ALSO TONIGHT IN LOW CLOUDS AND MOUNTAIN SNOW SHOWERS.
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 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1HRLY 07 08 09 10 11 12 13 14 15 16 17 18
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H M H H H H
BKW CONSISTENCY L L L H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H M M
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 12Z FRIDAY...
IFR POSSIBLE INTO FRIDAY ACROSS NORTHERN WV AND DOWN THROUGH THE
MOUNTAINS IN MIXED RAIN AND SNOW SHOWERS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/MZ/30
NEAR TERM...MZ
SHORT TERM...KTB
LONG TERM...30
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1203 PM EDT THU MAR 26 2015
.SYNOPSIS...
LOW PRESSURE AND ITS ASSOCIATED WARM FRONT WILL MOVE NORTHEAST
FROM THE OHIO VALLEY AND CROSS CENTRAL PENNSYLVANIA AND THE
SUSQUEHANNA VALLEY THIS AFTERNOON...BRINGING NUMEROUS SHOWERS AND
A FEW...FIRST THUNDERSTORMS OF THE SEASON. A STEADY COLD RAIN
WILL FALL NORTH OF THE LOWS TRACK...ACROSS THE NORTHWEST
MOUNTAINS. A TRAILING COLD FRONT WILL PUSH EAST THROUGH THE STATE
LATE TODAY. RAIN IS EXPECTED TO CHANGE TO SNOW OVER THE NORTHWEST
MOUNTAINS BY TONIGHT WITH LIGHT ACCUMULATIONS POSSIBLE. MUCH
COOLER AND DRIER CONDITIONS WILL RETURN FOR FRIDAY THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
NOON UPDATE FOR HIGHER TEMEPATURES AS WARM SURGE IS STRONGER THAN
EARLIER GUIDANCE. MANY SOUTHERN PA LOCATIONS WILL TOP 70 AND
CENTRAL AREAS COULD HIT 60.
PREVIOUS:
MADE ADJUSTMENTS TO THE TEMPERATURES BASED ON LATEST GUIDANCE AND
RAPIDLY UPDATING MODEL GUIDANCE. TEMPERATURE RISES HAVE BEEN SHARP
PAST FEW HOURS IN SOUTHERN AND CENTRAL PENNSYLVANIA. GUIDANCE
SHOWS NOSE OF 65 TO 70F AIR MOVING UP INTO SOUTH CENTRAL PA JUST
AHEAD OF THE COLD FRONT APPROACHING FROM THE WEST. TEMPERATURES
RANGE FROM AROUND 60 IN SOMERSET COUNTY TO NEAR 35 NEAR THE NEW
YORK BORDER AS OF 1045 AM.
SOME SHOWERS AND THUNDERSTORMS HAVE AFFECTED CENTRAL PA ON LEADING
EDGE OF THE WARM AIR. REPORTS OF HAIL AND/OR GRAUPEL COVERING
GROUND IN NORTHERN PA WHERE IT WAS 33-34F WHEN WITH THUNDER.
MODELS IMPLY SOME CAPE AND HRRR SHOWS A CONVECTIVE LINE DEVELOPING
THIS AFTERNOON. THE LINE DEVELOP AS COLD AIR MOVES INTO THE
NORTHWEST SO WE COULD HAVE RAIN TO SNOW ISSUES IN WARREN COUNTY AS
WE DEAL WITH THUNDER IN THE HARRISBURG-YORK-LANCASTER AREAS THIS
AFTERNOON. A SPRING ROLLER COASTER OF WEATHER.
TEMPERATURES WILL LIKELY RANGE THE 30S TO NEAR 40 IN NORTH TO
LOWER TO MID 60S IN SOUTH TODAY. SHOWERS IN NORTH WILL ADD TO THE
BEAUTY OF IT ALL. THE RAIN AND SHOWERS MOVE EAST THIS AFTERNOON
AND WE COULD SEE SOME WEAK ORGANIZATION AFTER 2 PM AND PERHAPS A
WEAK LINE OF LOW-TOPPED CONVECTION IN THE LOWER SUSQUEHANNA VALLEY
IN THE 5 TO 8 PM RANGE GIVE OR TAKE AN HOUR OR TOO. SEE HOW THE
HRRR DEVELOPS THIS FEATURE OVER TIME.
SO PUT THUNDER IN FORECAST IN CENTRAL WITH HIGHER PROBABILITY IN
SOUTHEAST THIS AFTERNOON AND EVENING. AND IN THE NORTHWEST...THE
RAIN SHOULD MIX WITH SNOW AFTER 6 PM OR SO AND ANY RESIDUAL RAIN
WILL TURN TO SNOW IN THE 7 TO 8 PM RANGE OR SO.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM FRIDAY/...
UPDATED TEMPS/GRIDS/POPS...ALL WILL SEE RAIN TO RAIN/SNOW
ISSUES SPREAD EAST WITH TIME...NO SIGNIFICANT ACCUMULATIONS
EXPECTED...BEST CHANCE DUSTING/COATING IN NW....
PREVIOUS:
AS LOW EXITS THE AREA TONIGHT...MDL SOUNDINGS BECOME COLD ENOUGH
TO SUPPORT A CHANGEOVER TO LGT SNOW/SNOW SHOWERS ACROSS THE NW
MTNS BY THU EVENING. FURTHER SOUTH...RESIDUAL MOISTURE ASCENDING
THE ALLEGHENIES SHOULD RESULT IN PRECIP ENDING AS -SHSN ACROSS
THE LAUREL HIGHLANDS THURSDAY NIGHT. A LIGHT ACCUM OF LESS THAN AN
INCH APPEARS LIKELY THU NIGHT FROM THE NW MTNS SOUTH ALONG THE
ALLEGHENIES TO SOMERSET CO.
THURSDAY SHOULD BE THE WARMEST DAY THIS SPRING OVER SOUTHERN
PA...WITH 18Z CONSALL MAXES IN THE 65-70F RANGE ACROSS THE
SOUTHERN VALLEYS NEAR THE MD BORDER. STRONG WINDS ALOFT WILL MIX
TO GROUND LVL IN THE WARM SECTOR ACROSS SOUTHERN PA. BUFKIT
SOUNDINGS SUPPORT GUSTS NR 30KTS ACROSS THE S TIER DURING THE AFTN
AND EARLY EVENING.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
DEEPENING BUT PROGRESSIVE UPPER TROF WILL BE MOVING EAST ACROSS
THE MID ATLANTIC STATES EARLY IN THE LONG TERM PERIOD. SIGNIFICANT
PRECIPITATION ASSOCIATED WITH THIS TROF SHOULD HAVE CONCLUDED BY
DAYTIME FRIDAY...BUT LINGERING SHOWERS ARE POSSIBLE INTO THE DAY
AS THE PUSH OF THE UPPER TROF HAS SLOWED A BIT IN RECENT GUIDANCE.
AT THE SFC...EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD INTO THE
REGION STARTING LATER FRIDAY WITH SEVERAL DRY DAYS INTO THE
WEEKEND.
THE DEEPNESS OF THIS UPPER TROF WILL BRING ANOTHER SHOT
UNSEASONABLY COLD AIR INTO THE REGION...ESPECIALLY NOTICEABLE
AFTER A COUPLE DAYS OF MORE SPRING LIKE CONDS WED AND THUR.
TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL OVER THE
WEEKEND.
A COMPARATIVELY WEAKER NRN STREAM WAVE WILL MOVE ACROSS THE UPPER
GREAT LAKES REGION AND TOWARDS THE NORTHEAST LATE SUNDAY INTO
MONDAY. THIS WILL CONTINUE THE CHILLY TEMPS AS WELL AS BRING THE
CHANCE FOR MORE SNOW SHOWERS.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
ISOLATED SHOWERS MOVING INTO WESTERN SECTIONS. SOME AREAS
STILL NEAR FREEZING. WILL CONTINUE TO MONITOR ABD UPDATE
AS NEEDED. 12Z TAFS WILL BE OUT SHORTLY.
UPDATED THE TAFS TO REFLECT THE SURGE OF WARM AIR AND THE
POTENTIAL SHOWERS AND MENTION OF VCTS IN SOUTHEASTERN AREAS THIS
AFTERNOON AND EVENING.
MVFR WILL LIKELY HOLD NEAR NY BORDER AND PERIODS OF VFR LIKELY
IN SOUTH-CENTRAL PA AS THE WARM AIR HAS SCOURED OUT THE LOW-LEVEL
COLD AIR. BUT THE FAST APPROACHING FRONT WILL BRING SHOWERS AND
MVFR/IFR TO THE REGION THIS AFTERNOON AND EVENING.
BEHIND THE FRONT MOST AREAS WILL GO UP OVERNIGHT MAINLY TO VFR AND
PATCHY MVFR. BUT IN THE SOUTHEAST COULD SEE SOME AREAS IFR/MVFR
BEFORE SUNRISE WITH PATCHY FOGGY DEVELOPING.
OUTLOOK...
FRI-SAT...MVFR/IFR WITH SNOW SHOWERS NORTH/WEST. VFR TO MVFR CENTRAL
AND EAST WITH SCHC OF -SHRA.
SUN...NO SIG WX/VFR.
MON...CHANCE OF LIGHT RAIN /LIGHT SNOW EARLY/ ACROSS NW HALF WITH
MVFR REDUCTIONS. VFR SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/LAMBERT
NEAR TERM...GRUMM/LAMBERT
SHORT TERM...GRUMM/DEVOIR
LONG TERM...DEVOIR/GARTNER
AVIATION...GRUMM/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1142 AM EDT THU MAR 26 2015
.SYNOPSIS...
LOW PRESSURE AND ITS ASSOCIATED WARM FRONT WILL MOVE NORTHEAST
FROM THE OHIO VALLEY AND CROSS CENTRAL PENNSYLVANIA AND THE
SUSQUEHANNA VALLEY THIS AFTERNOON...BRINGING NUMEROUS SHOWERS AND
A FEW...FIRST THUNDERSTORMS OF THE SEASON. A STEADY COLD RAIN
WILL FALL NORTH OF THE LOWS TRACK...ACROSS THE NORTHWEST
MOUNTAINS. A TRAILING COLD FRONT WILL PUSH EAST THROUGH THE STATE
LATE TODAY. RAIN IS EXPECTED TO CHANGE TO SNOW OVER THE NORTHWEST
MOUNTAINS BY TONIGHT WITH LIGHT ACCUMULATIONS POSSIBLE. MUCH
COOLER AND DRIER CONDITIONS WILL RETURN FOR FRIDAY THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
MADE ADJUSTMENTS TO THE TEMPERATURES BASED ON LATEST GUIDANCE AND
RAPIDLY UPDATING MODEL GUIDANCE. TEMPERATURE RISES HAVE BEEN
SHARP PAST FEW HOURS IN SOUTHERN AND CENTRAL PENNSYLVANIA.
GUIDANCE SHOWS NOSE OF 65 TO 70F AIR MOVING UP INTO SOUTH CENTRAL
PA JUST AHEAD OF THE COLD FRONT APPROACHING FROM THE WEST.
TEMPERATURES RANGE FROM AROUND 60 IN SOMERSET COUNTY TO NEAR 35
NEAR THE NEW YORK BORDER AS OF 1045 AM.
SOME SHOWERS AND THUNDERSTORMS HAVE AFFECTED CENTRAL PA ON LEADING
EDGE OF THE WARM AIR. REPORTS OF HAIL AND/OR GRAUPEL COVERING
GROUND IN NORTHERN PA WHERE IT WAS 33-34F WHEN WITH THUNDER.
MODELS IMPLY SOME CAPE AND HRRR SHOWS A CONVECTIVE LINE DEVELOPING
THIS AFTERNOON. THE LINE DEVELOP AS COLD AIR MOVES INTO THE
NORTHWEST SO WE COULD HAVE RAIN TO SNOW ISSUES IN WARREN COUNTY AS
WE DEAL WITH THUNDER IN THE HARRISBURG-YORK-LANCASTER AREAS THIS
AFTERNOON. A SPRING ROLLER COASTER OF WEATHER.
TEMPERATURES WILL LIKELY RANGE THE 30S TO NEAR 40 IN NORTH TO
LOWER TO MID 60S IN SOUTH TODAY. SHOWERS IN NORTH WILL ADD TO THE
BEAUTY OF IT ALL. THE RAIN AND SHOWERS MOVE EAST THIS AFTERNOON
AND WE COULD SEE SOME WEAK ORGANIZATION AFTER 2 PM AND PERHAPS A
WEAK LINE OF LOW-TOPPED CONVECTION IN THE LOWER SUSQUEHANNA VALLEY
IN THE 5 TO 8 PM RANGE GIVE OR TAKE AN HOUR OR TOO. SEE HOW THE
HRRR DEVELOPS THIS FEATURE OVER TIME.
SO PUT THUNDER IN FORECAST IN CENTRAL WITH HIGHER PROBABILITY IN
SOUTHEAST THIS AFTERNOON AND EVENING. AND IN THE NORTHWEST...THE
RAIN SHOULD MIX WITH SNOW AFTER 6 PM OR SO AND ANY RESIDUAL RAIN
WILL TURN TO SNOW IN THE 7 TO 8 PM RANGE OR SO.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM FRIDAY/...
UPDATED TEMPS/GRIDS/POPS...ALL WILL SEE RAIN TO RAIN/SNOW
ISSUES SPREAD EAST WITH TIME...NO SIGNIFICANT ACCUMULATIONS
EXPECTED...BEST CHANCE DUSTING/COATING IN NW....
PREVIOUS:
AS LOW EXITS THE AREA TONIGHT...MDL SOUNDINGS BECOME COLD ENOUGH
TO SUPPORT A CHANGEOVER TO LGT SNOW/SNOW SHOWERS ACROSS THE NW
MTNS BY THU EVENING. FURTHER SOUTH...RESIDUAL MOISTURE ASCENDING
THE ALLEGHENIES SHOULD RESULT IN PRECIP ENDING AS -SHSN ACROSS
THE LAUREL HIGHLANDS THURSDAY NIGHT. A LIGHT ACCUM OF LESS THAN AN
INCH APPEARS LIKELY THU NIGHT FROM THE NW MTNS SOUTH ALONG THE
ALLEGHENIES TO SOMERSET CO.
THURSDAY SHOULD BE THE WARMEST DAY THIS SPRING OVER SOUTHERN
PA...WITH 18Z CONSALL MAXES IN THE 65-70F RANGE ACROSS THE
SOUTHERN VALLEYS NEAR THE MD BORDER. STRONG WINDS ALOFT WILL MIX
TO GROUND LVL IN THE WARM SECTOR ACROSS SOUTHERN PA. BUFKIT
SOUNDINGS SUPPORT GUSTS NR 30KTS ACROSS THE S TIER DURING THE AFTN
AND EARLY EVENING.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
DEEPENING BUT PROGRESSIVE UPPER TROF WILL BE MOVING EAST ACROSS
THE MID ATLANTIC STATES EARLY IN THE LONG TERM PERIOD. SIGNIFICANT
PRECIPITATION ASSOCIATED WITH THIS TROF SHOULD HAVE CONCLUDED BY
DAYTIME FRIDAY...BUT LINGERING SHOWERS ARE POSSIBLE INTO THE DAY
AS THE PUSH OF THE UPPER TROF HAS SLOWED A BIT IN RECENT GUIDANCE.
AT THE SFC...EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD INTO THE
REGION STARTING LATER FRIDAY WITH SEVERAL DRY DAYS INTO THE
WEEKEND.
THE DEEPNESS OF THIS UPPER TROF WILL BRING ANOTHER SHOT
UNSEASONABLY COLD AIR INTO THE REGION...ESPECIALLY NOTICEABLE
AFTER A COUPLE DAYS OF MORE SPRING LIKE CONDS WED AND THUR.
TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL OVER THE
WEEKEND.
A COMPARATIVELY WEAKER NRN STREAM WAVE WILL MOVE ACROSS THE UPPER
GREAT LAKES REGION AND TOWARDS THE NORTHEAST LATE SUNDAY INTO
MONDAY. THIS WILL CONTINUE THE CHILLY TEMPS AS WELL AS BRING THE
CHANCE FOR MORE SNOW SHOWERS.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
ISOLATED SHOWERS MOVING INTO WESTERN SECTIONS. SOME AREAS
STILL NEAR FREEZING. WILL CONTINUE TO MONITOR ABD UPDATE
AS NEEDED. 12Z TAFS WILL BE OUT SHORTLY.
UPDATED THE TAFS TO REFLECT THE SURGE OF WARM AIR AND THE
POTENTIAL SHOWERS AND MENTION OF VCTS IN SOUTHEASTERN AREAS THIS
AFTERNOON AND EVENING.
MVFR WILL LIKELY HOLD NEAR NY BORDER AND PERIODS OF VFR LIKELY
IN SOUTH-CENTRAL PA AS THE WARM AIR HAS SCOURED OUT THE LOW-LEVEL
COLD AIR. BUT THE FAST APPROACHING FRONT WILL BRING SHOWERS AND
MVFR/IFR TO THE REGION THIS AFTERNOON AND EVENING.
BEHIND THE FRONT MOST AREAS WILL GO UP OVERNIGHT MAINLY TO VFR AND
PATCHY MVFR. BUT IN THE SOUTHEAST COULD SEE SOME AREAS IFR/MVFR
BEFORE SUNRISE WITH PATCHY FOGGY DEVELOPING.
OUTLOOK...
FRI-SAT...MVFR/IFR WITH SNOW SHOWERS NORTH/WEST. VFR TO MVFR CENTRAL
AND EAST WITH SCHC OF -SHRA.
SUN...NO SIG WX/VFR.
MON...CHANCE OF LIGHT RAIN /LIGHT SNOW EARLY/ ACROSS NW HALF WITH
MVFR REDUCTIONS. VFR SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/LAMBERT
NEAR TERM...GRUMM/LAMBERT
SHORT TERM...GRUMM/DEVOIR
LONG TERM...DEVOIR/GARTNER
AVIATION...GRUMM/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1106 AM EDT THU MAR 26 2015
.SYNOPSIS...
LOW PRESSURE AND ITS ASSOCIATED WARM FRONT WILL MOVE NORTHEAST
FROM THE OHIO VALLEY AND CROSS CENTRAL PENNSYLVANIA AND THE
SUSQUEHANNA VALLEY THIS AFTERNOON...BRINGING NUMEROUS SHOWERS AND
A FEW...FIRST THUNDERSTORMS OF THE SEASON. A STEADY COLD RAIN
WILL FALL NORTH OF THE LOWS TRACK...ACROSS THE NORTHWEST
MOUNTAINS. A TRAILING COLD FRONT WILL PUSH EAST THROUGH THE STATE
LATE TODAY. RAIN IS EXPECTED TO CHANGE TO SNOW OVER THE NORTHWEST
MOUNTAINS BY TONIGHT WITH LIGHT ACCUMULATIONS POSSIBLE. MUCH
COOLER AND DRIER CONDITIONS WILL RETURN FOR FRIDAY THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
MADE ADJUSTMENTS TO THE TEMPERATURES BASED ON LATEST GUIDANCE AND
RAPIDLY UPDATING MODEL GUIDANCE. TEMPERATURE RISES HAVE BEEN
SHARP PAST FEW HOURS IN SOUTHERN AND CENTRAL PENNSYLVANIA.
GUIDANCE SHOWS NOSE OF 65 TO 70F AIR MOVING UP INTO SOUTH CENTRAL
PA JUST AHEAD OF THE COLD FRONT APPROACHING FROM THE WEST.
TEMPERATURES RANGE FROM AROUND 60 IN SOMERSET COUNTY TO NEAR 35
NEAR THE NEW YORK BORDER AS OF 1045 AM.
SOME SHOWERS AND THUNDERSTORMS HAVE AFFECTED CENTRAL PA ON LEADING
EDGE OF THE WARM AIR. REPORTS OF HAIL AND/OR GRAUPEL COVERING
GROUND IN NORTHERN PA WHERE IT WAS 33-34F WHEN WITH THUNDER.
MODELS IMPLY SOME CAPE AND HRRR SHOWS A CONVECTIVE LINE DEVELOPING
THIS AFTERNOON. THE LINE DEVELOP AS COLD AIR MOVES INTO THE
NORTHWEST SO WE COULD HAVE RAIN TO SNOW ISSUES IN WARREN COUNTY AS
WE DEAL WITH THUNDER IN THE HARRISBURG-YORK-LANCASTER AREAS THIS
AFTERNOON. A SPRING ROLLER COASTER OF WEATHER.
TEMPERATURES WILL LIKELY RANGE THE 30S TO NEAR 40 IN NORTH TO
LOWER TO MID 60S IN SOUTH TODAY. SHOWERS IN NORTH WILL ADD TO THE
BEAUTY OF IT ALL. THE RAIN AND SHOWERS MOVE EAST THIS AFTERNOON
AND WE COULD SEE SOME WEAK ORGANIZATION AFTER 2 PM AND PERHAPS A
WEAK LINE OF LOW-TOPPED CONVECTION IN THE LOWER SUSQUEHANNA VALLEY
IN THE 5 TO 8 PM RANGE GIVE OR TAKE AN HOUR OR TOO. SEE HOW THE
HRRR DEVELOPS THIS FEATURE OVER TIME.
SO PUT THUNDER IN FORECAST IN CENTRAL WITH HIGHER PROBABILITY IN
SOUTHEAST THIS AFTERNOON AND EVENING. AND IN THE NORTHWEST...THE
RAIN SHOULD MIX WITH SNOW AFTER 6 PM OR SO AND ANY RESIDUAL RAIN
WILL TURN TO SNOW IN THE 7 TO 8 PM RANGE OR SO.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM FRIDAY/...
...UPDATED TEMPS/GRIDS/POPS...ALL WILL SEE RAIN TO RAIN/SNOW
ISSUES SPREAD EAST WITH TIME...NO SIGNIFICANT ACCUMULATIONS
EXPECTED...BEST CHANCE DUSTING/COATING IN NW....
PREVIOUS:
AS LOW EXITS THE AREA TONIGHT...MDL SOUNDINGS BECOME COLD ENOUGH
TO SUPPORT A CHANGEOVER TO LGT SNOW/SNOW SHOWERS ACROSS THE NW
MTNS BY THU EVENING. FURTHER SOUTH...RESIDUAL MOISTURE ASCENDING
THE ALLEGHENIES SHOULD RESULT IN PRECIP ENDING AS -SHSN ACROSS
THE LAUREL HIGHLANDS THURSDAY NIGHT. A LIGHT ACCUM OF LESS THAN AN
INCH APPEARS LIKELY THU NIGHT FROM THE NW MTNS SOUTH ALONG THE
ALLEGHENIES TO SOMERSET CO.
THURSDAY SHOULD BE THE WARMEST DAY THIS SPRING OVER SOUTHERN
PA...WITH 18Z CONSALL MAXES IN THE 65-70F RANGE ACROSS THE
SOUTHERN VALLEYS NEAR THE MD BORDER. STRONG WINDS ALOFT WILL MIX
TO GROUND LVL IN THE WARM SECTOR ACROSS SOUTHERN PA. BUFKIT
SOUNDINGS SUPPORT GUSTS NR 30KTS ACROSS THE S TIER DURING THE AFTN
AND EARLY EVENING.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
DEEPENING BUT PROGRESSIVE UPPER TROF WILL BE MOVING EAST ACROSS
THE MID ATLANTIC STATES EARLY IN THE LONG TERM PERIOD. SIGNIFICANT
PRECIPITATION ASSOCIATED WITH THIS TROF SHOULD HAVE CONCLUDED BY
DAYTIME FRIDAY...BUT LINGERING SHOWERS ARE POSSIBLE INTO THE DAY
AS THE PUSH OF THE UPPER TROF HAS SLOWED A BIT IN RECENT GUIDANCE.
AT THE SFC...EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD INTO THE
REGION STARTING LATER FRIDAY WITH SEVERAL DRY DAYS INTO THE
WEEKEND.
THE DEEPNESS OF THIS UPPER TROF WILL BRING ANOTHER SHOT
UNSEASONABLY COLD AIR INTO THE REGION...ESPECIALLY NOTICEABLE
AFTER A COUPLE DAYS OF MORE SPRING LIKE CONDS WED AND THUR.
TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL OVER THE
WEEKEND.
A COMPARATIVELY WEAKER NRN STREAM WAVE WILL MOVE ACROSS THE UPPER
GREAT LAKES REGION AND TOWARDS THE NORTHEAST LATE SUNDAY INTO
MONDAY. THIS WILL CONTINUE THE CHILLY TEMPS AS WELL AS BRING THE
CHANCE FOR MORE SNOW SHOWERS.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
ISOLATED SHOWERS MOVING INTO WESTERN SECTIONS. SOME AREAS
STILL NEAR FREEZING. WILL CONTINUE TO MONITOR ABD UPDATE
AS NEEDED. 12Z TAFS WILL BE OUT SHORTLY.
EARLIER DISCUSSION BELOW.
MINOR ADJUSTMENTS TO TAFS AT 09Z.
ISOLATED SHOWERS ACROSS WESTERN PA...BUT TEMPERATURES ABOVE
FREEZING ACROSS THE WEST.
06Z INFO.
STILL SOME LOWER CLDS ACROSS THE FAR EAST. THESE SEEM TO BE
MOVING EASTWARD...SO DID NOT KEEP ANY IN AT IPT. ALSO BACKED OFF
ON NON-VFR CONDITIONS AT UNV AND AOO OVERNIGHT. SAME FOR
JST...GIVEN LIGHT SOUTH FLOW. STILL LOOKING AT DENSE FOG AND LOW
CIGS AT BFD.
HARD TO SEE BFD IMPROVING MUCH TODAY...AS SHOWERS WILL MOVE INTO
NW PA SHORTLY AFTER SUNRISE.
FURTHER EAST...MUCH OF THE DAY WILL BE DRY WITH VFR CONDITIONS
AND MILD TEMPERATURES AFTER A COLD START. TEMPS AT OR NEAR
FREEZING IN SPOTS AS OF 130 AM...BUT NOT EXPECTING ANY RAIN
BEFORE TEMPS WARM UP AFTER SUNRISE.
EXPECT SW WINDS TO MIX DOWN SHORTLY AFTER SUNRISE. LEFT LLWS
OUT FOR NOW...BORDERLINE THIS MORNING.
EXPECT POOR FLYING CONDITIONS THU NIGHT...AS COLDER AIR WORKS
IN...AND MOST AREAS SEE MVFR AND IFR CONDITIONS. RAIN WILL LIKELY
MIX WITH OR CHANGE TO SNOW LATE ACROSS THE NW AND FAR WESTERN
AREAS.
OUTLOOK...
FRI-SAT...MVFR/IFR WITH SNOW SHOWERS NORTH/WEST. VFR TO MVFR CENTRAL
AND EAST WITH SCHC OF -SHRA.
SUN...NO SIG WX/VFR.
MON...CHANCE OF LIGHT RAIN /LIGHT SNOW EARLY/ ACROSS NW HALF WITH
MVFR REDUCTIONS. VFR SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/LAMBERT
NEAR TERM...GRUMM/LAMBERT
SHORT TERM...GRUMM/DEVOIR
LONG TERM...DEVOIR/GARTNER
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
858 AM EDT THU MAR 26 2015
.SYNOPSIS...
LOW PRESSURE AND ITS ASSOCIATED WARM FRONT WILL MOVE NORTHEAST
FROM THE OHIO VALLEY AND CROSS CENTRAL PENNSYLVANIA AND THE
SUSQUEHANNA VALLEY THIS AFTERNOON...BRINGING NUMEROUS SHOWERS AND
A FEW...FIRST THUNDERSTORMS OF THE SEASON. A STEADY COLD RAIN
WILL FALL NORTH OF THE LOWS TRACK...ACROSS THE NORTHWEST
MOUNTAINS. A TRAILING COLD FRONT WILL PUSH EAST THROUGH THE STATE
LATE TODAY. RAIN IS EXPECTED TO CHANGE TO SNOW OVER THE NORTHWEST
MOUNTAINS BY TONIGHT WITH LIGHT ACCUMULATIONS POSSIBLE. MUCH
COOLER AND DRIER CONDITIONS WILL RETURN FOR FRIDAY THROUGH SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
VARYING AMOUNTS OF MID LEVEL CLOUDS CONTINUE TO INCREASE ACROSS
CENTRAL PA THIS MORNING...AHEAD OF A WAVY FRONTAL BOUNDARY
EXTENDING FROM JUST SOUTH OF THE MASON DIXON LINE...TO THE OHIO
RIVER VALLEY.
AREAS OF LOWER STRATUS WERE SPREAD ACRS THE LOWER SUSQ
VALLEY...AND THE NORTHERN MTNS. LOCALLY DENSE FOG WILL PERSIST
ACROSS THE NW MTNS THROUGH AT LEAST THIS MORNING...BEFORE LIKELY
IMPROVING A BIT TO AROUND 1SM AS A STEADIER...COLD RAIN SPREADS
NE ACROSS THAT REGION.
HIGH RES MODELS AND LATEST ENSEMBLE GUIDANCE CONTINUE TO TRACK
SFC LOW INTO SOUTHWEST PA BY AFTERNOON...AND ACROSS THE REST OF
EASTERN PA BY EARLY THIS EVENING. THIS TRACK WILL BRING A COLD
RAIN TO THE NW COUNTIES...WHERE 100 PCT POPS ARE SUPPORTED. SFC
WARM FRONT...WHICH REMAINS HUNG UP JUST SW OF THE LAURELS THIS
MORNING...WILL LIFT INTO THE SOUTHERN AND EASTERN COUNTIES...
RESULTING IN A MUCH WARMER AND MAINLY DRY LATE AM/EARLY AFTN...
AND ALSO SETTING THE STAGE FOR MARGINAL CAPE AND POSSIBLE THUNDER
AS THE COLD FRONT CROSSES LATE THIS AFTERNOON AND EVENING. SPC
GENERAL THUNDER INDICATED OVER THE SOUTHEAST HALF OF CENTRAL PA
WITH MARGINAL AREA CONFINED TO THE DEL MARVA REGION.
LATEST...11Z HRRR DEPICTS A BKN LINE OF HEAVY SHRA/EMBEDDED TSRA
DEVELOPING DURING THE MID AFTERNOON HOURS NEAR A LINE FROM
KELM...TO KUNV AND KIDI. THIS LINE WILL STRENGTHEN AS IT CROSSES
THE CENTRAL MTNS AND MOVES INTO THE SUSQ VALLEY BETWEEN 21-22Z
/WHERE MUCH BETTER ML CAPES OF 400-800 J/KG...AND WEAK-MDT 0-1KM
SHEAR WILL RESIDE/.
BEST RAIN CHCS ACROSS SOUTHEAST PA COME DURING LATE AFTN AND EARLY
EVENING WITH PASSAGE OF TRAILING COLD FRONT. AS PREVIOUSLY
MENTIONED...MARGINALLY UNSTABLE BOUNDARY LAYER COMBINED WITH LG
SCALE FORCING IN ADVANCE OF MID LVL SHORTWAVE...SHOULD SUPPORT A
FEW TSRA ACROSS THE SOUTHERN COUNTIES DURING THE LATE
AFTN/EVENING. HIGHS WILL VARY STRONGLY FROM NORTH TO SOUTH...WITH
MAXES ONLY IN THE LOWER 40S NORTH AND RANGING TO THE UPPER 60S
OVER THE LOWER SUSQ IN THE WARM SECTOR.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
AS LOW EXITS THE AREA TONIGHT...MDL SOUNDINGS BECOME COLD ENOUGH
TO SUPPORT A CHANGEOVER TO LGT SNOW/SNOW SHOWERS ACROSS THE NW
MTNS BY THU EVENING. FURTHER SOUTH...RESIDUAL MOISTURE ASCENDING
THE ALLEGHENIES SHOULD RESULT IN PRECIP ENDING AS -SHSN ACROSS THE
LAUREL HIGHLANDS THURSDAY NIGHT. A LIGHT ACCUM OF LESS THAN AN
INCH APPEARS LIKELY THU NIGHT FROM THE NW MTNS SOUTH ALONG THE
ALLEGHENIES TO SOMERSET CO.
THURSDAY SHOULD BE THE WARMEST DAY THIS SPRING OVER SOUTHERN
PA...WITH 18Z CONSALL MAXES IN THE 65-70F RANGE ACROSS THE
SOUTHERN VALLEYS NEAR THE MD BORDER. STRONG WINDS ALOFT WILL MIX
TO GROUND LVL IN THE WARM SECTOR ACROSS SOUTHERN PA. BUFKIT
SOUNDINGS SUPPORT GUSTS NR 30KTS ACROSS THE S TIER DURING THE AFTN
AND EARLY EVENING.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
DEEPENING BUT PROGRESSIVE UPPER TROF WILL BE MOVING EAST ACROSS
THE MID ATLANTIC STATES EARLY IN THE LONG TERM PERIOD. SIGNIFICANT
PRECIPITATION ASSOCIATED WITH THIS TROF SHOULD HAVE CONCLUDED BY
DAYTIME FRIDAY...BUT LINGERING SHOWERS ARE POSSIBLE INTO THE DAY
AS THE PUSH OF THE UPPER TROF HAS SLOWED A BIT IN RECENT GUIDANCE.
AT THE SFC...EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD INTO THE
REGION STARTING LATER FRIDAY WITH SEVERAL DRY DAYS INTO THE
WEEKEND.
THE DEEPNESS OF THIS UPPER TROF WILL BRING ANOTHER SHOT
UNSEASONABLY COLD AIR INTO THE REGION...ESPECIALLY NOTICEABLE
AFTER A COUPLE DAYS OF MORE SPRING LIKE CONDS WED AND THUR.
TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL OVER THE
WEEKEND.
A COMPARATIVELY WEAKER NRN STREAM WAVE WILL MOVE ACROSS THE UPPER
GREAT LAKES REGION AND TOWARDS THE NORTHEAST LATE SUNDAY INTOMONDAY.
THIS WILL CONTINUE THE CHILLY TEMPS AS WELL AS BRING THE CHANCE
FOR MORE SNOW SHOWERS.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
ISOLATED SHOWERS MOVING INTO WESTERN SECTIONS. SOME AREAS
STILL NEAR FREEZING. WILL CONTINUE TO MONITOR ABD UPDATE
AS NEEDED. 12Z TAFS WILL BE OUT SHORTLY.
EARLIER DISCUSSION BELOW.
MINOR ADJUSTMENTS TO TAFS AT 09Z.
ISOLATED SHOWERS ACROSS WESTERN PA...BUT TEMPERATURES ABOVE
FREEZING ACROSS THE WEST.
06Z INFO.
STILL SOME LOWER CLDS ACROSS THE FAR EAST. THESE SEEM TO BE
MOVING EASTWARD...SO DID NOT KEEP ANY IN AT IPT. ALSO BACKED OFF
ON NON-VFR CONDITIONS AT UNV AND AOO OVERNIGHT. SAME FOR
JST...GIVEN LIGHT SOUTH FLOW. STILL LOOKING AT DENSE FOG AND LOW
CIGS AT BFD.
HARD TO SEE BFD IMPROVING MUCH TODAY...AS SHOWERS WILL MOVE INTO
NW PA SHORTLY AFTER SUNRISE.
FURTHER EAST...MUCH OF THE DAY WILL BE DRY WITH VFR CONDITONS
AND MILD TEMPERATURES AFTER A COLD START. TEMPS AT OR NEAR
FREEZING IN SPOTS AS OF 130 AM...BUT NOT EXPECTING ANY RAIN
BEFORE TEMPS WARM UP AFTER SUNRISE.
EXPECT SW WINDS TO MIX DOWN SHORTLY AFTER SUNRISE. LEFT LLWS
OUT FOR NOW...BORDERLINE THIS MORNING.
EXPECT POOR FLYING CONDITIONS THU NIGHT...AS COLDER AIR WORKS
IN...AND MOST AREAS SEE MVFR AND IFR CONDITIONS. RAIN WILL LIKELY
MIX WITH OR CHANGE TO SNOW LATE ACROSS THE NW AND FAR WESTERN
AREAS.
OUTLOOK...
FRI-SAT...MVFR/IFR WITH SNOW SHOWERS NORTH/WEST. VFR TO MVFR CENTRAL
AND EAST WITH SCHC OF -SHRA.
SUN...NO SIG WX/VFR.
MON...CHANCE OF LIGHT RAIN /LIGHT SNOW EARLY/ ACROSS NW HALF WITH
MVFR REDUCTIONS. VFR SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT/DEVIOR
NEAR TERM...LAMBERT/DEVIOR
SHORT TERM...DEVOIR/FITZGERALD/CERU
LONG TERM...DEVOIR/GARTNER
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1056 AM EDT THU MAR 26 2015
.SYNOPSIS...
WARM SOUTHERLY FLOW WILL GRADUALLY INCREASE AHEAD OF AN APPROACHING
COLD FRONT TODAY. THE COLD FRONT WILL CROSS THE WESTERN CAROLINAS
AND NORTHEAST GEORGIA TONIGHT. A TRAILING UPPER LEVEL DISTURBANCE
WILL THEN CROSS THE AREA FRIDAY THROUGH FRIDAY NIGHT. DRY AND COOL
HIGH PRESSURE WILL SETTLE IN OVER THE WEEKEND. A LOW PRESSURE
CLIPPER SYSTEM AND ASSOCIATED COLD FRONT WILL PASS OVER THE REGION
ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM...LATEST RAP AND NAM PROFILES DO NOT REFLECT AS MUCH
INSTABILITY THIS AFTN AS PREVIOUSLY ANTICIPATED...AND IN FACT ARE
GENERALLY DRIER ACRS THE AREA. FRONT STILL EXPECTED TO ENTER THE
MTNS A LITTLE AFTER SUNSET WITH PROFILES BECOMING MORE UNSTABLE ACRS
THE AREA OVERNIGHT IN THE WARM SECTOR. LOWERED POPS ACRS THE
PIEDMONT TO A MAXIMUM OF SCHC THIS AFTN WHILE MAINTAINING A SLOW
INCREASING TREND OVER THE HIGHER TERRAIN. STILL ANTICIPATING MAX
TEMPS TOWARD THE WARM END OF GUIDANCE...NO CHANGES MADE IN THAT
REGARD.
AS OF 345 AM...WEAK ISENTROPIC LIFT AT 295 K WILL SUPPORT WIDESPREAD
LOW CEILINGS AND PATCHY FOG EARLY THIS MORNING. THE THICK LOW CLOUDS
WILL LIKELY LINGER A FEW HOURS AFTER SUNRISE. IN ADDITION...SCT TI
WIDELY SCT -SHRA WILL CONTINUE ACROSS THE REGION THROUGH SUNRISE.
THE 0Z NAM INDICATES THAT LLVL WINDS WILL VEER FROM THE SOUTHWEST
SHORTLY AFTER SUNRISE...RESULTING LITTLE TO NO ISENTROPIC LIFT AND
ENDING UPSLOPE FLOW. CLOUD COVER MAY BEGIN TO THIN ONCE LLVL LIFT
HAS CEASED...ESPECIALLY FROM MID DAY THROUGH THE AFTERNOON.
INCREASING SUN AND MARGINALLY GUSTY SOUTHWEST WINDS SHOULD
RESULT IN MILD AFTERNOON TEMPERATURES ACROSS THE CWA. A BLEND OF
PREFERRED TEMPERATURE GUIDANCE YIELD HIGHS FROM AROUND 70 WITHIN THE
MTN VALLEYS TO THE MID TO UPPER 70S EAST OF I-85. DEWPOINTS WILL
RISE INTO THE 50S THIS AFTERNOON.
NEAR TERM MODELS INDICATE THAT A COLD FRONT WILL SLIDE ACROSS
EASTERN KY/TN THIS AFTERNOON...CROSSING THE SOUTHERN APPALACHIANS
BETWEEN 0Z-3Z...THEN PUSHING EAST OF THE PIEDMONT BY 9Z. POOLING
DEWPOINTS AND MILD TEMPERATURES SHOULD YIELD CAPE VALUES BETWEEN 500-
1000 J/KG ALONG AND AHEAD OF THE COLD FRONT. A BAND OF SHRA/TSRA IS
FORECAST TO REACH THE TN/NC LINE BETWEEN 0Z TO 3Z. I WILL INCREASE
POPS THROUGH THIS EVENING...PEAKING POPS AT 6Z IN THE HIGH LIKELY TO
CATEGORICAL RANGES. I WILL MENTION SHOWERS WITH CHC/SCHC OF TSRA. IN
THE WAKE OF THE FRONT...BRISK CAA WILL BUILD ACROSS THE WESTERN
CAROLINAS AND NORTHEAST GEORGIA. BY 12Z FRI...TN BORDER COUNTIES MAY
COOL H850 TEMPS TO 0 TO -2C. MIN TEMPERATURES ARE FORECAST TO RANGE
IN THE U30S WITHIN MTN VALLEYS TO MID TO UPPER 40S EAST. THE CAA
COULD SUPPORT A FEW TN BORDER -SHSN.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 315 AM THURSDAY...MODELS IN AGREEMENT THAT THERE WILL BE SOME
LINGERING PRECIP ACRS THE EASTERN HALF OF THE CWFA FRIDAY
MORNING...AS MOST UPGLIDE CONTINUES BEHIND THE SFC COLD FRONT. THIS
PRECIP WILL ALSO BE INCREASING DPVA...AS A SHARP UPPER TROF AXIS
APPROACHES FROM THE WEST. TEMPS WILL BE TRICKY...AS PRECIP/CLOUDS
DIMINISH FROM WEST TO EAST DURING THE AFTN HOURS. THICKNESSES FALL
QUICKLY AS WELL...SO EXPECT TEMPS TO ONLY RISE INTO THE 50S.
FRIDAY NIGHT...THERE WILL BE SOME LINGERING NW FLOW SHWR ACTIVITY AS
A VIGOROUS VORT MAX ROUNDS THE BASE OF THE UPPER TROF AS IT CROSSES
THE NC MTNS. MEANWHILE...850 MB TEMPS WILL FALL TO THE -4 TO -8C
RANGE. SO EXPECT MAINLY SNOW SHWRS WITH SOME MINOR ACCUMS. STILL
THINK IT WILL BE SUB-ADVISORY. THE MTNS WILL LIKELY EXPERIENCE AN
ADVECTIVE FREEZE OVERNIGHT...WITH LOW TEMPS IN THE 20S. THE PIEDMONT
WILL SEE TEMPS IN THE 30S...WITH ISOLD FREEZING TEMPS AND POSSIBLY
SOME PATCHY FROST...IF WINDS DECOUPLE.
SATURDAY...THE LLVL CAA WILL CONTINUE...AS ANOTHER SHORTWAVE ROUNDS
THE BASE OF THE UPPER TROF. EXPECT NW FLOW SHOWERS TO DIMINISH
HOWEVER...AS MOISTURE WANES. TEMPS WILL BE ABOUT 15-20 DEG BELOW
NORMAL...WITH A BREEZE IN THE MTNS MAKING IT FEEL EVEN COLDER.
SATURDAY NIGHT...THE CENTER OF CANADIAN HIGH PRES WILL SETTLE IN
ACRS THE CWFA...USHERING IN THE COLDEST TEMPS WE/VE SEEN IN A COUPLE
WEEKS. A HARD FREEZE IS EXPECTED ACRS THE ENTIRE MTN ZONES...AND A
LIGHT-MODERATE FREEZE ELSEWHERE. MIN TEMPS SUNDAY MORNING LOOK TO BE
IN THE TEENS TO MID 20S IN THE MTNS AND MID 20S TO LWR 30S ACRS THE
PIEDMONT. THESE MIN TEMPS WILL APPROACH RECORD LOWS ACRS THE
PIEDMONT (SEE CLIMATE SECTION BELOW).
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 330 AM THURSDAY...THE UPPER TROF WILL EXIT OFF THE EAST COAST
SUNDAY...AND A SHARP REBOUND IN HEIGHTS IS EXPECTED. SUNDAY WILL
STILL BE A CHILLY DAY...BUT EXPECTED TO BE AT LEAST A COUPLE
CATEGORIES WARMER THAN SATURDAY AFTER A COLD START. AS THE CENTER OF
SFC HIGH PRES SHIFTS EAST...WEAK RETURN FLOW SHUD COMMENCE. SUNDAY
NIGHT SHUD BE BACK TO NEAR NORMAL WITH LOWS IN THE MAINLY IN THE MID-
UPR 30S IN THE MTNS AND UPR 30S TO LWR 40S ACRS THE PIEDMONT.
MONDAY THRU WEDNESDAY...ANOTHER SHORTWAVE TROF WILL DIG INTO THE
GREAT LAKES AND USHER IN A CLIPPER LOW TO THE REGION. THE TRAILING
COLD FRONT OF THAT SYSTEM WILL CROSS THE CWFA EITHER MONDAY MORNING
(PER GFS) OR MONDAY EVENING (PER ECMWF). BOTH SOLNS SHOW ENUF
MOISTURE FOR A BAND OF PRECIP WITH THE FROPA. TEMPS BEHIND THE FRONT
WILL NOT BE THAT COLD AS THE AIR MASS WILL BE FROM THE PACIFIC. THE
GFS BRINGS A MORE VIGOROUS SOUTHERN STREAM SHORTWAVE BY
WEDNESDAY...WITH A RETURN OF POPS. THE ECMWF KEEPS THE AREA DRY.
GOING WITH THE SUPERBLEND THAT INCLUDES THE LATEST WPC
GUIDANCE...HAVE A SLGT CHC TO CHC POP ON MONDAY WITH THE
FRONT...THEN CHC POPS RETURN TUESDAY NIGHT THRU WEDNESDAY (MORE IN
LINE WITH THE GFS). TEMPS WILL BE NEAR OR SLIGHTLY ABOVE NORMAL
DURING THIS PERIOD.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
AT KCLT /15Z UPDATE/...LOWER MVFR CIGS WILL LIFT GRADUALLY TO LOW
VFR BY EARLY AFTN. A COLD FRONT IS EXPECTED TO SWEEP EAST ACROSS THE
CAROLINAS THIS EVENING. AS THE FRONT APPROACHES...SOUTHWEST WINDS
WILL STRENGTHEN TO AROUND 10 KTS...WITH GUSTS NEAR 20 KTS BETWEEN
16Z-03Z. CLOUD BASES SHOULD LIFT FURTHER INTO VFR RANGE BY EARLY
EVENING. THE POSITION OF THE COLD FRONT IS FORECAST TO REACH THE I-
85 CORRIDOR AROUND 6Z FRI. POOLING INSTABILITY MAY SUPPORT SCT TSRA
BETWEEN 6Z-9Z...I WILL HIGHLIGHT WITH A PROB30. BY 9Z...NORTH WINDS
WILL DEVELOP IN THE WAKE OF THE FRONT...ALSO WITH MVFR CEILINGS AND -
SHRA.
ELSEWHERE...CLOUDS ARE FORECAST TO IMPROVE TO VFR BY EARLY AFTN...AS
SOUTHWEST WINDS BECOME MARGINALLY GUSTY. A COLD FRONT WILL PUSH
ACROSS THE MTNS LATE THIS AFTERNOON AND EVENING. A FIELD OF WEAK
CAPE IS EXPECTED TO DEVELOP ALONG AND AHEAD OF THE FRONT...POSSIBLY
SUPPORTING TSRA. NORTH WINDS AND MVFR CEILINGS ARE FORECAST IN THE
WAKE OF THE FRONT AFTER 7Z.
OUTLOOK...IMPROVING CONDITIONS ARE LIKELY ON FRIDAY IN THE WAKE OF A
COLD FRONT...BUT SCATTERED SHOWERS WILL CONTINUE TO PRODUCE SOME
RESTRICTIONS. HIGH PRESSURE WILL BUILD OVER THE REGION BEGINNING
FRIDAY NIGHT PRODUCING VFR CONDITIONS.
CONFIDENCE TABLE...
15-21Z 21-03Z 03-09Z 09-12Z
KCLT HIGH 95% HIGH 100% HIGH 85% HIGH 83%
KGSP HIGH 97% HIGH 100% HIGH 100% MED 66%
KAVL HIGH 83% HIGH 100% MED 69% MED 66%
KHKY HIGH 95% HIGH 100% HIGH 89% LOW 43%
KGMU HIGH 97% HIGH 100% HIGH 100% MED 66%
KAND MED 76% HIGH 100% HIGH 89% HIGH 94%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MINIMUM TEMPERATURES FOR MARCH 28TH...
GSP 26 1982
CLT 25 1982
AVL 11 1887
RECORD MINIMUM TEMPERATURES FOR MARCH 29TH...
GSP 26 1899
CLT 26 2013
AVL 19 1982
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...ARK
NEAR TERM...NED/WIMBERLEY
SHORT TERM...ARK
LONG TERM...ARK
AVIATION...NED/WIMBERLEY
CLIMATE...ARK
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
1005 AM EDT THU MAR 26 2015
.DISCUSSION...13Z SURFACE MAP PLACES COLD FRONT THROUGH NW TN AND
THE WRN 1/3RD OF KY...WITH JUST SCATTERED SHOWERS MOVING ACROSS NRN
PARTS OF THE CUMBERLAND PLATEAU. NAM 12KM FORECAST SOUNDINGS DO SHOW
MUCAPES (MOST UNSTABLE) OF 800 TO 1200 J/KG FOR OUR PLATEAU COUNTIES
AT MID TO LATE AFTERNOON...SO SHOULD SEE A FEW NON-SEVERE STORMS
THIS AFTERNOON INTO THE EARLY EVENING HOURS (MAINLY ERN AREAS JUST
AHEAD OF THE COLD FRONT).
LATEST RAP AND HRR MODEL RUNS REALLY DON`T ADVANCE MUCH PRE-FRONTAL
CONVECTION INTO OUR EXTREME EASTERN COUNTIES THROUGH 22Z TODAY...SO
MAY LOWER POPS BY ABOUT 20 PERCENT OR MORE IN THOSE AREAS.
OTHERWISE...FORECAST GRIDS RUNNING ON TRACK AS FAR TEMPS AND OTHER
HOURLY FIELDS ARE CONCERNED. WILL UPDATE THE GRIDS TO MAKE MINOR
CHANGE MENTIONED AND TO ALSO REMOVE ANY MORNING WORDING FROM ZFP
PRODUCT.
OUR FREEZE PROGRAM WILL BEGIN TODAY FOR ALL BUT...WISE AND RUSSELL
COUNTIES OF SW VA...AS WELL AS THE SMOKY AND NE TN MTN AREAS. WE
WILL LIKELY BE ISSUING A FREEZE WATCH FOR MOST OF THE AREA WITH THE
AFTERNOON PACKAGE...FOR FRIDAY NIGHT WITH LOWS EXPECTED IN THE 20S
ACROSS THE FREEZE PROGRAM AREAS.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1058 AM CDT THU MAR 26 2015
.DISCUSSION...
COLD FRONT AND ASSOCIATED SHOWERS AND THUNDERSTORMS ARE CURRENTLY
MOVING OFF THE COAST AND ACROSS THE COASTAL WATERS. WHILE THE
GREATEST CONCENTRATION IS OFF THE COAST...SOME LINGERING LIGHT/
MODERATE RAIN AREAS WILL HANG AROUND FOR ANOTHER HOUR OR SO.
THE FORECAST PACKAGE HAS THINGS COVERED...AND MIGHT UPDATE EVERYTHING
ONCE THE RAINS EXIT OUR AREA. 42
&&
PREV DISCUSSION... /ISSUED 401 AM CDT THU MAR 26 2015/
DISCUSSION...
AT 08Z SFC ANALYSIS SHOWS THE COLD FRONT STRETCHING FROM THE
ARKLATEX SW TO C TX AND NW HILL COUNTRY. A THIN LINE OF SHOWERS
HAS DEVELOPED ALONG AND JUST AHEAD OF THE FRONT. LLJ AT 850MB
STRETCHES FROM THE LOWER TX COAST NE THROUGH E TX AND TOWARDS THE
MISS RIVER VALLEY. WATER VAPOR AND 500MB ANALYSIS SHOW TROUGH AXIS
STRETCHING FROM THE N GREAT LAKES THROUGH THE PLAINS. POLAR JET
STRETCHES FROM THE S PLAINS NE TOWARDS THE GREAT LAKES WITH RIGHT
ENTRANCE REGION OVER OK MOVING EAST TOWARDS ARK. ANOTHER JET
STREAK WAS FOUND OVER THE N ROCKIES WHICH SHOULD FURTHER DEEPEN
THE TROUGH WITH UPPER LEVEL RIDGING OVER THE PAC COAST.
LATEST RAP/HRRR/3KM TXTECH WRF/4 KM WRF ARW ALL HAVE A PRETTY
GOOD HANDLE ON COLD FRONTAL PASSAGE ACROSS SE TX. LATEST 07Z HRRR
HAS INITIALIZED WELL AND BASED THE FIRST DAY FORECAST ON A BLEND
OF THESE TRENDS WITH THE RAP AND 3KM TX TECH WRF. FRONT SHOULD
REACH KCLL/KUTS 10-11Z...KIAH/KSGR/KHOU AROUND 13Z AND THEN OFF
THE COAST 15-16Z. MODELS DO SUPPORT CONVECTION INCREASING IN
COVERAGE MAINLY SOUTH OF HOUSTON AND ALONG THE COAST WHERE THE
FRONT INTERACTS WITH HIGHER MOISTURE. FORECAST WILL KEEP HIGHER
POPS FOR THE COASTAL AREAS AND OFFSHORE THROUGH 18Z. RAIN CHANCES
CLEAR OUT QUICKLY FROM 15-18Z INLAND. ANY THUNDERSTORM ACTIVITY
MAY BECOME STRONG BUT NOT LIKELY SEVERE DUE TO CAPPING AND LIMITED
INSTABILITY. THE 00Z CRP SOUNDING SHOWS A PRETTY GOOD CAP AT
800-750MB.
TEMP FORECAST WILL BE A CHALLENGE BECAUSE OF STRONG COLD
ADVECTION BEHIND THE FRONT. TEMPS ARE IN THE LOW/MID 60S THIS
MORNING AND MAY INCREASE A FEW DEGREES AHEAD OF THE FRONT MAINLY
ALONG THE COAST. TEMPS MAY DROP INTO THE 50S BEHIND THE FRONT BUT
AS CONVECTION/CLOUD COVER CLEARS...MAY GET SOME SLIGHT HEATING IN
THE AFTERNOON TO OFF SET COLD ADVECTION. SHORT RANGE MODELS KEEP
TEMPS IN THE 60S WHICH LOOKS REASONABLE.
FRI MORNING SHOULD BE A COOL START TO THE DAY WITH MIN TEMPS BACK
INTO THE 40S BUT MAX TEMPS SHOULD TOP OUT IN THE 70S. TEMPS
INCREASE OVER THE WEEKEND WITH WEAK UPPER LEVEL RIDGING OVER TX.
THE GFS/ECMWF DIVERGE IN THEIR SOLUTIONS OVER THE WEEKEND AND INTO
NEXT WEEK. WHILE THE MODELS THEMSELVES HAVE HAD RUN TO RUN
CONSISTENCY...THERE HAS NOT BEEN ANY CONSISTENCY WITH EACH OTHER.
THE PROBLEM SEEMS TO BE HOW EACH MODEL IS HANDLING A TROUGH THAT
PUSHES INTO THE PACIFIC COAST LATE FRI INTO SAT. THE ECMWF CUTS
OFF SOME VORTICITY FROM THIS TROUGH AND HAS IT RETROGRADE BACK
INTO THE PACIFIC WITH THE MAIN WAVE MOVING ACROSS THE PAC NW AND
INTO THE PLAINS BY SUNDAY. THE GFS DOES SIMILARLY WITH THE MAIN
WAVE BUT HAS A MORE COHERENT CLOSED OFF UPPER LOW OVER
CALIFORNIA/BAJA LATE SUNDAY. THIS SYSTEM THEN MOVES ACROSS THE S
ROCKIES INTO TX ON TUE. THE ECMWF HAS A MUCH WEAKER SYSTEM AND HAS
A STALLED FRONT ACROSS THE AREA. THIS MAKES THE FORECAST
CHALLENGING BECAUSE IF THE ECMWF VERIFIES THERE WILL BE LITTLE
WEATHER IMPACT. IF THE GFS IS CORRECT THEN THE TROUGH SWINGS OVER
SE TX WITH NEG TILT AND VERY FAVORABLE FOR HEAVY RAINFALL/SEVERE
WEATHER. FOR WHAT IT IS WORTH THE CANADIAN MODEL MIGHT BE A
COMPROMISE BETWEEN THE GFS/ECMWF BUT PERHAPS SUPPORTING THE ECMWF
A BIT MORE. FORECAST WILL KEEP 30/40 POPS AND MAX TEMPS WILL BE A
COUPLE DEGREES COOLER DUE TO POSSIBLE RAIN CHANCES AND CLOUD
COVER. THE SYSTEM CLEARS OUT EARLY NEXT WED WITH NO REAL CHANGE IN
AIRMASS. TEMPS NEXT WEEK COULD BE A GOOD 5-8 DEGREES ABOVE NORMAL.
39
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 65 45 74 51 78 / 20 0 0 0 0
HOUSTON (IAH) 67 49 75 54 79 / 50 0 0 0 0
GALVESTON (GLS) 68 54 70 60 73 / 60 0 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 1 AM CDT FRIDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 4 AM CDT FRIDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
&&
$$
DISCUSSION...42
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
625 AM CDT THU MAR 26 2015
.DISCUSSION...
SEE THE 12Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
THE COLD FRONT WAS MOVING THROUGH THE KCLL AND KUTS SITES AT 11Z.
MOST OF THE SHOWER AND ISOLATED THUNDERSTORM ACTIVITY WAS ALONG
AND AHEAD OF THE FRONT. TIMED THE FRONTAL PASSAGE WITH A
CONSENSUS OF THE RAP13 AND GUIDANCE. THERE SHOULD BE ABOUT A TWO-
HOUR PERIOD OF THUNDERSTORM CHANCES AHEAD OF THE FRONT...AND
STRETCHED THIS OUT TO A THREE-HOUR PERIOD AT KLBX AND KGLS DUE TO
TIMING UNCERTAINTY. MVFR CONDITIONS FOLLOWING THE FRONTAL PASSAGE
WILL GRADUALLY LIFT TO VFR DURING THE MID AFTERNOON PERIOD. WINDS
BEHIND THE FRONT WILL BE STRONGEST TOWARD THE COAST AND MORE
SOUTHERN SITES. DO EXPECT THE WINDS TO DIMINISH DURING THE
EVENING.
40
&&
.PREV DISCUSSION... /ISSUED 401 AM CDT THU MAR 26 2015/
DISCUSSION...
AT 08Z SFC ANALYSIS SHOWS THE COLD FRONT STRETCHING FROM THE
ARKLATEX SW TO C TX AND NW HILL COUNTRY. A THIN LINE OF SHOWERS
HAS DEVELOPED ALONG AND JUST AHEAD OF THE FRONT. LLJ AT 850MB
STRETCHES FROM THE LOWER TX COAST NE THROUGH E TX AND TOWARDS THE
MISS RIVER VALLEY. WATER VAPOR AND 500MB ANALYSIS SHOW TROUGH AXIS
STRETCHING FROM THE N GREAT LAKES THROUGH THE PLAINS. POLAR JET
STRETCHES FROM THE S PLAINS NE TOWARDS THE GREAT LAKES WITH RIGHT
ENTRANCE REGION OVER OK MOVING EAST TOWARDS ARK. ANOTHER JET
STREAK WAS FOUND OVER THE N ROCKIES WHICH SHOULD FURTHER DEEPEN
THE TROUGH WITH UPPER LEVEL RIDGING OVER THE PAC COAST.
LATEST RAP/HRRR/3KM TXTECH WRF/4 KM WRF ARW ALL HAVE A PRETTY
GOOD HANDLE ON COLD FRONTAL PASSAGE ACROSS SE TX. LATEST 07Z HRRR
HAS INITIALIZED WELL AND BASED THE FIRST DAY FORECAST ON A BLEND
OF THESE TRENDS WITH THE RAP AND 3KM TX TECH WRF. FRONT SHOULD
REACH KCLL/KUTS 10-11Z...KIAH/KSGR/KHOU AROUND 13Z AND THEN OFF
THE COAST 15-16Z. MODELS DO SUPPORT CONVECTION INCREASING IN
COVERAGE MAINLY SOUTH OF HOUSTON AND ALONG THE COAST WHERE THE
FRONT INTERACTS WITH HIGHER MOISTURE. FORECAST WILL KEEP HIGHER
POPS FOR THE COASTAL AREAS AND OFFSHORE THROUGH 18Z. RAIN CHANCES
CLEAR OUT QUICKLY FROM 15-18Z INLAND. ANY THUNDERSTORM ACTIVITY
MAY BECOME STRONG BUT NOT LIKELY SEVERE DUE TO CAPPING AND LIMITED
INSTABILITY. THE 00Z CRP SOUNDING SHOWS A PRETTY GOOD CAP AT
800-750MB.
TEMP FORECAST WILL BE A CHALLENGE BECAUSE OF STRONG COLD
ADVECTION BEHIND THE FRONT. TEMPS ARE IN THE LOW/MID 60S THIS
MORNING AND MAY INCREASE A FEW DEGREES AHEAD OF THE FRONT MAINLY
ALONG THE COAST. TEMPS MAY DROP INTO THE 50S BEHIND THE FRONT BUT
AS CONVECTION/CLOUD COVER CLEARS...MAY GET SOME SLIGHT HEATING IN
THE AFTERNOON TO OFF SET COLD ADVECTION. SHORT RANGE MODELS KEEP
TEMPS IN THE 60S WHICH LOOKS REASONABLE.
FRI MORNING SHOULD BE A COOL START TO THE DAY WITH MIN TEMPS BACK
INTO THE 40S BUT MAX TEMPS SHOULD TOP OUT IN THE 70S. TEMPS
INCREASE OVER THE WEEKEND WITH WEAK UPPER LEVEL RIDGING OVER TX.
THE GFS/ECMWF DIVERGE IN THEIR SOLUTIONS OVER THE WEEKEND AND INTO
NEXT WEEK. WHILE THE MODELS THEMSELVES HAVE HAD RUN TO RUN
CONSISTENCY...THERE HAS NOT BEEN ANY CONSISTENCY WITH EACH OTHER.
THE PROBLEM SEEMS TO BE HOW EACH MODEL IS HANDLING A TROUGH THAT
PUSHES INTO THE PACIFIC COAST LATE FRI INTO SAT. THE ECMWF CUTS
OFF SOME VORTICITY FROM THIS TROUGH AND HAS IT RETROGRADE BACK
INTO THE PACIFIC WITH THE MAIN WAVE MOVING ACROSS THE PAC NW AND
INTO THE PLAINS BY SUNDAY. THE GFS DOES SIMILARLY WITH THE MAIN
WAVE BUT HAS A MORE COHERENT CLOSED OFF UPPER LOW OVER
CALIFORNIA/BAJA LATE SUNDAY. THIS SYSTEM THEN MOVES ACROSS THE S
ROCKIES INTO TX ON TUE. THE ECMWF HAS A MUCH WEAKER SYSTEM AND HAS
A STALLED FRONT ACROSS THE AREA. THIS MAKES THE FORECAST
CHALLENGING BECAUSE IF THE ECMWF VERIFIES THERE WILL BE LITTLE
WEATHER IMPACT. IF THE GFS IS CORRECT THEN THE TROUGH SWINGS OVER
SE TX WITH NEG TILT AND VERY FAVORABLE FOR HEAVY RAINFALL/SEVERE
WEATHER. FOR WHAT IT IS WORTH THE CANADIAN MODEL MIGHT BE A
COMPROMISE BETWEEN THE GFS/ECMWF BUT PERHAPS SUPPORTING THE ECMWF
A BIT MORE. FORECAST WILL KEEP 30/40 POPS AND MAX TEMPS WILL BE A
COUPLE DEGREES COOLER DUE TO POSSIBLE RAIN CHANCES AND CLOUD
COVER. THE SYSTEM CLEARS OUT EARLY NEXT WED WITH NO REAL CHANGE IN
AIRMASS. TEMPS NEXT WEEK COULD BE A GOOD 5-8 DEGREES ABOVE NORMAL.
39
MARINE...
A STRONG COLD FRONT WILL MOVE OFF THE COAST DURING THE MID AND
LATE MORNING. WINDS BEHIND THE FRONT ARE EXPECTED TO STRENGTHEN TO
ADVISORY LEVELS DURING THE EARLY AFTERNOON AND THEN PERSIST
THROUGH MOST OF THE EVENING. STRONGER WIND SPEEDS WILL LINGER OVER
THE OFFSHORE WATERS AFTER MIDNIGHT BEFORE DECREASING TOWARD
SUNRISE. HIGH PRESSURE WILL THEN BUILD INTO THE AREA ON FRIDAY.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 65 45 74 51 78 / 20 0 0 0 0
HOUSTON (IAH) 67 49 75 54 79 / 50 0 0 0 0
GALVESTON (GLS) 68 54 70 60 73 / 60 0 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM CDT FRIDAY
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 4 AM CDT FRIDAY
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT 20 TO 60 NM.
&&
$$
DISCUSSION...39
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1007 AM EDT THU MAR 26 2015
.SYNOPSIS...
A COLD FRONT TRAILED FROM THE GREAT LAKES TO A LOW OVER THE
SOUTHERN PLAINS EARLY THIS MORNING. THIS LOW WILL TRACK NORTHEAST
AND WILL PUSH A STRONG COLD FRONT THROUGH THE AREA TONIGHT. MUCH
COLDER AIR WILL BE MOVING IN BEHIND THE COLD FRONT FOR THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1007 AM EDT THURSDAY...
ADJUSTED CLOUD COVER THIS MORNING INTO THIS AFTERNOON TO BETTER
CAPTURE SUNSHINE NOTED ON THIS MORNINGS SATELLITE IMAGES. USED A
BLEND OF CANDIAN AND HRRR FOR CLOUD COVER INTO THE AFTERNOON.
MODIFIED TEMPERATURES FOR THIS MORNING WITH LATEST SFC OBS AND
MODEL TRENDS. LEANED TOWARDS THE WARM MOS FOR LATE MORNING WITH
THE SUNSHINE IN THE WEST. DECREASED POPS FOR THIS MORNING AND
ADJUSTED THEM TOWARDS A BLEND OF THE NAM AND HRRR INTO THIS
AFTERNOON. WITH MOST OF THE CONVECTION NOT RETURNING TO AFTER 21Z
THIS AFTERNOON. SCATTERED SHOWERS AND THUNDERSTORMS WILL ACCOMPANY
AND PRECEDE A COLD FRONT THIS AFTERNOON INTO TONIGHT. TIMING OF
FRONT LOOKS TO BE BETWEEN 23Z AND 05Z. THE CAPE LOOKED
MARGINAL/WEAK THIS AFTERNOON BECAUSE OF WARM LAYER AT 700 MB. AS
OF 13Z DAY ONE CONVECTION OUTLOOK STILL HAS OUR REGION IN THE
GENERAL THUNDERSTORM AREA WITH THE MRGL TO OUR EAST ALONG THE
COASTAL PLAINS OF VIRGINIA AND NORTH CAROLINA. MORE CHANGES LATER
THIS MORNING.
AS OF 430 AM EDT THURSDAY...
PERSISTENT WEDGE REMAINED IN PLACE EARLY THIS MORNING. BAND OF
SHOWERS AND ISOLATED THUNDERSTORMS TRACKING TOWARD DANVILLE AND
SOUTHEAST COUNTIES OF THE FORECAST AREA WILL BE ELEVATED OVER A
SHALLOW BUT STRONG INVERSION. JUST ABOVE THE INVERSION
LEVEL...STRATUS HAD FORMED IN ALL BUT THE FAR WESTERN COUNTY
WARNING AREA. HIGHER ELEVATIONS WERE IN THE CLOUDS WITH DRIZZLE
AND FOG REPORTED.
LATEST HRRR AND WRF RUNS HAD BEST PROBABILITY OF SHOWERS THIS
MORNING IN SOUTHEAST HALF OF THE FORECAST AREA...ESPECIALLY EAST
OF DANVILLE AND LYNCHBURG. BUFKIT SOUNDINGS SHOWED THE WEDGE
BREAKING IN MOST LOCATIONS BY NOON WITH THE STRATUS AND FOG
LIFTING AND WINDS COMING AROUND TO THE SOUTHWEST.
THIS AFTERNOON WHEN THE FORECAST AREA IS OUT OF THE WEDGE AND INTO
THE WARM SECTOR AHEAD OF THE FRONT EXPECTING ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL BE ABOUT 10
TO 15 DEGREES ABOVE NORMAL...BUT EVEN WITH THE WARMING...ONLY
MARGINAL CAPE IS EXPECTED DUE A WARM LAYER AROUND 700 MB THIS
AFTERNOON.
AT 4AM THE COLD FRONT EXTENDED FROM PITTSBURGH TO LITTLE ROCK. LOW
PRESSURE WILL MOVE ALONG THE BOUNDARY TONIGHT. A STRONG UPPER
TROF BEGINS TO DIG IN THE CENTRAL UNITED STATES TONIGHT. SHOWERS
WILL BE WIDESPREAD ALONG AND BEHIND THE FRONT. KEPT THE CHANCE OF
THUNDERSTORMS IN FOR THIS EVENING. 00Z LOCAL WRF WAS AN HOUR OF
TWO FASTER WITH THE FRONTAL PASSAGE THAN THE NAM AND GFS. AT THIS
TIME EXPECT THE FRONT TO REACH THE FAR WESTERN COUNTY WARNING AREA
AROUND 00Z/8PM AND EXIT THE EASTERN COUNTIES AROUND 05Z/1AM.
TEMPERATURES WILL DROP QUICKLY BEHIND THE FRONT TONIGHT. AIR MASS
WILL BE COLD ENOUGH TO SUPPORT SNOW IN THE HIGHEST ELEVATIONS WEST
OF THE BLUE RIDGE BY EARLY FRIDAY MORNING. THE STRONG COLD AIR
ADVECTION COMBINED WITH PRESSURE RISES OF 5 TO 10MB/6HRS WILL
RESULT IN GUSTY WINDS TONIGHT. BUFKIT SOUNDINGS SUGGESTED
OCCASIONAL GUST OF 25 TO 35 MPH.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
AS OF 345 AM EDT THURSDAY...
MODEL GENERATION OF WAVES ALONG THE COLD FRONT HAVE SLOWED ITS
PROJECTED PASSAGE ACROSS THE REGION. AND WHILE THE FRONT WILL BE
CLEAR OF US TO THE EAST BY FRIDAY...THE FRONTAL WAVES BEING DRIVEN
BY UPPER LEVEL SHORT WAVE ENERGY WILL KEEP RESIDUAL PRECIPITATION
ACROSS THE EAST FRIDAY MORNING. AT THE SAME TIME NORTHWEST WINDS
WILL BE GENERATING UPSLOPE PRECIPITATION WEST OF THE BLUE RIDGE AS
MUCH COLDER COLDER AIR MOVES IN. THE UPSLOPE PRECIPITATION WILL BE
RAIN FOR MOST LOCATIONS WEST OF THE RIDGE BUT THE HIGHER ELEVATIONS
OF THE FAR WESTERN SLOPES WILL SEE SNOW SHOWERS. GIVEN THE STRENGTH
OF THE SUN THIS TIME OF YEAR AND WARM ANTECEDENT CONDITIONS NO
ACCUMULATION IS EXPECTED DURING THE DAYTIME ON FRIDAY. BY FRIDAY
NIGHT THE HEART OF THE VERY COLD AIR WILL SURGE INTO THE
REGION...ALLOWING FOR UPSLOPE PRECIPITATION TO CHANGE TO SNOW FOR
ALL LOCATIONS WEST OF THE RIDGE. WITH NO SUN TO COMPETE WITH...SOME
ACCUMULATION IS POSSIBLE FRIDAY NIGHT MAINLY FOR THE FAR WESTERN
SLOPES WHERE AMOUNTS WILL GENERALLY BE AN INCH OR LESS. HIGH PRESSURE
WILL THEN BUILD IN FOR THE WEEKEND...BRINGING AN END TO THE SNOW
SHOWERS SATURDAY MORNING WITH FAIR WEATHER ON TAP THROUGH SUNDAY.
TEMPERATURES WILL BE RUNNING 10 TO 15 DEGREES BELOW NORMAL THROUGH
THE PERIOD WITH SATURDAY BEING THE COLDEST DAY OF THIS STRETCH. LOWS
SATURDAY MORNING WILL BOTTOM OUT GENERALLY IN THE TEENS WEST OF THE
RIDGE TO MIDDLE 20S EAST. WINDS WILL ALSO BE BLUSTERY AS THE COLDER
AIR MOVES IN FRIDAY AND FRIDAY NIGHT...PRODUCING WIND CHILL VALUES
SATURDAY MORNING OF ZERO TO 10 ABOVE WEST TO THE LOWER AND MIDDLE 20S
EAST. HIGHS SATURDAY WILL ONLY BE IN THE LOW TO MID 30S WEST AND IN
THE MID TO UPPER 40S EAST. THANKFULLY TEMPERATURES WILL START TO
REBOUND AS WE CLOSE OUT THE WEEKEND WITH THE COLD AREA OF HIGH
PRESSURE SINKING TO OUR SOUTHEAST...ALLOWING OUR WINDS TO COME
AROUND TO A SOUTHWESTERLY DIRECTION AND BRING WARMER AIR BACK INTO
THE REGION.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 400 PM EDT WEDNESDAY...
NORTHWEST FLOW PREVAILS THROUGH MONDAY WITH AN ALBERTA CLIPPER
PROGGED TO TRACK ACROSS THE REGION SUNDAY NIGHT TO MONDAY. THE GFS
IS FASTER AND STRONGER WITH THIS SYSTEM THAN THE ECMWF...BUT GIVEN
THE PATTERN IN PLACE AT THAT POINT...THE GFS FORECAST SEEMS MORE
REASONABLE. POPS ARE QUESTIONABLE WITH THIS SYSTEM...SO HAVE JUST
INDICATED LOW CHC POPS IN THE WEST FOR NOW UNTIL BETTER CONSENSUS IS
OBTAINED FROM THE MODELS ON THIS SYSTEM. BEYOND THAT...THE UPPER
FLOW BECOMES MORE ZONAL AND THE FOCUS WILL BE ON A HIGHLY
KINEMATIC...PACIFIC BASED SYSTEM IN THE SOUTHERN STREAM EXPECTED TO
REACH THE CWA AT THE END OF THE FORECAST PERIOD. THIS COULD BE A
SEVERE WEATHER SYSTEM FOR THE SOUTHERN PLAINS TO THE SOUTHEAST
STATES...BUT MORE QUESTIONABLE FOR OUR AREA. YIELDED TOWARD THE
SUPERBLEND FOR POPS IN THE LAST TWO PERIODS TO BETTER AGREE WITH
NEIGHBORS. HOWEVER...TIMING OF THE ARRIVAL OF WARM ADVECTION
PRECIPITATION ASSOCIATED WITH THIS SYSTEM REMAINS HIGHLY
QUESTIONABLE AT THIS POINT. THE ZONAL FLOW WILL YIELD TO NEAR NORMAL
TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
AS OF 720 AM EDT THURSDAY...
RADAR SHOWED CLUSTER OF SHOWERS AND ISOLATED THUNDERSTORMS IN
SOUTH CENTRAL VIRGINIA MOVING NORTH THIS MORNING. SHOWERS WILL BE
OUT OF THE KLYH BY 13Z/9AM. BUFKIT FORECAST SHOWED CEILINGS
LOWERING TO IFR EARLY THIS MORNING UNDER A SHALLOW BUT STRONG
INVERSION. PERSISTENT WEDGE AND INVERSION WILL BREAK THIS
MORNING. MEDIUM CONFIDENCE THAT CEILINGS WILL IMPROVE BACK TO VFR
AT KROA/KBCB/KDAN AND KLYH BY 17Z/NOON. WINDS WILL BE GUSTY OUT OF
THE SOUTHWEST ONCE THE WEDGE ERODES.
HIGH CONFIDENCE THAT A STRONG COLD FRONT WILL CROSS THROUGH THE
REGION JUST AFTER 00Z/7PM AT KLWB AND KBLF. THE FRONT IS EXPECTED
TO REACH KLYH AROUND 04Z/MIDNIGHT AND KDAN AROUND 05Z/1AM. EXPECT
A BAND OF MODERATE TO HEAVY SHOWERS ALONG AND JUST BEHIND THE
FRONT. VISIBILITY MAY DROP TO MVFR LEVELS IN THE HEAVIER RAIN.
WINDS WILL BECOME NORTHWEST BEHIND THE FRONT WITH GUSTS AT 20 TO
30 KNOTS.
SHOWERS AND GUSTY WINDS WILL CONTINUE THROUGH FRIDAY AS MUCH
COLDER AIR SURGES INTO THE REGION. SNOW SHOWERS ARE LIKELY WITH
MVFR CEILINGS AND VISIBILITIES IN THE WESTERN UPSLOPE AREAS OF THE
MOUNTAINS LATE TONIGHT THROUGH FRIDAY NIGHT. WINDS WILL DIMINISH
SATURDAY WITH VFR CONDITIONS AS HIGH PRESSURE BUILDS INTO THE
AREA. VFR WEATHER IS EXPECTED SUNDAY AND MONDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/KK
SHORT TERM...MBS
LONG TERM...RAB
AVIATION...AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
727 AM EDT THU MAR 26 2015
.SYNOPSIS...
A COLD FRONT TRAILED FROM THE GREAT LAKES TO A LOW OVER THE
SOUTHERN PLAINS EARLY THIS MORNING. THIS LOW WILL TRACK NORTHEAST
AND WILL PUSH A STRONG COLD FRONT THROUGH THE AREA TONIGHT. MUCH
COLDER AIR WILL BE MOVING IN BEHIND THE COLD FRONT FOR THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 430 AM EDT THURSDAY...
PERSISTENT WEDGE REMAINED IN PLACE EARLY THIS MORNING. BAND OF
SHOWERS AND ISOLATED THUNDERSTORMS TRACKING TOWARD DANVILLE AND
SOUTHEAST COUNTIES OF THE FORECAST AREA WILL BE ELEVATED OVER A
SHALLOW BUT STRONG INVERSION. JUST ABOVE THE INVERSION
LEVEL...STRATUS HAD FORMED IN ALL BUT THE FAR WESTERN COUNTY
WARNING AREA. HIGHER ELEVATIONS WERE IN THE CLOUDS WITH DRIZZLE
AND FOG REPORTED.
LATEST HRRR AND WRF RUNS HAD BEST PROBABILITY OF SHOWERS THIS
MORNING IN SOUTHEAST HALF OF THE FORECAST AREA...ESPECIALLY EAST
OF DANVILLE AND LYNCHBURG. BUFKIT SOUNDINGS SHOWED THE WEDGE
BREAKING IN MOST LOCATIONS BY NOON WITH THE STRATUS AND FOG
LIFTING AND WINDS COMING AROUND TO THE SOUTHWEST.
THIS AFTERNOON WHEN THE FORECAST AREA IS OUT OF THE WEDGE AND INTO
THE WARM SECTOR AHEAD OF THE FRONT EXPECTING ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL BE ABOUT 10
TO 15 DEGREES ABOVE NORMAL...BUT EVEN WITH THE WARMING...ONLY
MARGINAL CAPE IS EXPECTED DUE A WARM LAYER AROUND 700 MB THIS
AFTERNOON.
AT 4AM THE COLD FRONT EXTENDED FROM PITTSBURGH TO LITTLE ROCK. LOW
PRESSURE WILL MOVE ALONG THE BOUNDARY TONIGHT. A STRONG UPPER
TROF BEGINS TO DIG IN THE CENTRAL UNITED STATES TONIGHT. SHOWERS
WILL BE WIDESPREAD ALONG AND BEHIND THE FRONT. KEPT THE CHANCE OF
THUNDERSTORMS IN FOR THIS EVENING. 00Z LOCAL WRF WAS AN HOUR OF
TWO FASTER WITH THE FRONTAL PASSAGE THAN THE NAM AND GFS. AT THIS
TIME EXPECT THE FRONT TO REACH THE FAR WESTERN COUNTY WARNING AREA
AROUND 00Z/8PM AND EXIT THE EASTERN COUNTIES AROUND 05Z/1AM.
TEMPERATURES WILL DROP QUICKLY BEHIND THE FRONT TONIGHT. AIR MASS
WILL BE COLD ENOUGH TO SUPPORT SNOW IN THE HIGHEST ELEVATIONS WEST
OF THE BLUE RIDGE BY EARLY FRIDAY MORNING. THE STRONG COLD AIR
ADVECTION COMBINED WITH PRESSURE RISES OF 5 TO 10MB/6HRS WILL
RESULT IN GUSTY WINDS TONIGHT. BUFKIT SOUNDINGS SUGGESTED
OCCASIONAL GUST OF 25 TO 35 MPH.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
AS OF 345 AM EDT THURSDAY...
MODEL GENERATION OF WAVES ALONG THE COLD FRONT HAVE SLOWED ITS
PROJECTED PASSAGE ACROSS THE REGION. AND WHILE THE FRONT WILL BE
CLEAR OF US TO THE EAST BY FRIDAY...THE FRONTAL WAVES BEING DRIVEN
BY UPPER LEVEL SHORT WAVE ENERGY WILL KEEP RESIDUAL PRECIPITATION
ACROSS THE EAST FRIDAY MORNING. AT THE SAME TIME NORTHWEST WINDS
WILL BE GENERATING UPSLOPE PRECIPITATION WEST OF THE BLUE RIDGE AS
MUCH COLDER COLDER AIR MOVES IN. THE UPSLOPE PRECIPITATION WILL BE
RAIN FOR MOST LOCATIONS WEST OF THE RIDGE BUT THE HIGHER ELEVATIONS
OF THE FAR WESTERN SLOPES WILL SEE SNOW SHOWERS. GIVEN THE STRENGTH
OF THE SUN THIS TIME OF YEAR AND WARM ANTECEDENT CONDITIONS NO
ACCUMULATION IS EXPECTED DURING THE DAYTIME ON FRIDAY. BY FRIDAY
NIGHT THE HEART OF THE VERY COLD AIR WILL SURGE INTO THE
REGION...ALLOWING FOR UPSLOPE PRECIPITATION TO CHANGE TO SNOW FOR
ALL LOCATIONS WEST OF THE RIDGE. WITH NO SUN TO COMPETE WITH...SOME
ACCUMULATION IS POSSIBLE FRIDAY NIGHT MAINLY FOR THE FAR WESTERN
SLOPES WHERE AMOUNTS WILL GENERALLY BE AN INCH OR LESS. HIGH PRESSURE
WILL THEN BUILD IN FOR THE WEEKEND...BRINGING AN END TO THE SNOW
SHOWERS SATURDAY MORNING WITH FAIR WEATHER ON TAP THROUGH SUNDAY.
TEMPERATURES WILL BE RUNNING 10 TO 15 DEGREES BELOW NORMAL THROUGH
THE PERIOD WITH SATURDAY BEING THE COLDEST DAY OF THIS STRETCH. LOWS
SATURDAY MORNING WILL BOTTOM OUT GENERALLY IN THE TEENS WEST OF THE
RIDGE TO MIDDLE 20S EAST. WINDS WILL ALSO BE BLUSTERY AS THE COLDER
AIR MOVES IN FRIDAY AND FRIDAY NIGHT...PRODUCING WIND CHILL VALUES
SATURDAY MORNING OF ZERO TO 10 ABOVE WEST TO THE LOWER AND MIDDLE 20S
EAST. HIGHS SATURDAY WILL ONLY BE IN THE LOW TO MID 30S WEST AND IN
THE MID TO UPPER 40S EAST. THANKFULLY TEMPERATURES WILL START TO
REBOUND AS WE CLOSE OUT THE WEEKEND WITH THE COLD AREA OF HIGH
PRESSURE SINKING TO OUR SOUTHEAST...ALLOWING OUR WINDS TO COME
AROUND TO A SOUTHWESTERLY DIRECTION AND BRING WARMER AIR BACK INTO
THE REGION.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 400 PM EDT WEDNESDAY...
NORTHWEST FLOW PREVAILS THROUGH MONDAY WITH AN ALBERTA CLIPPER
PROGGED TO TRACK ACROSS THE REGION SUNDAY NIGHT TO MONDAY. THE GFS
IS FASTER AND STRONGER WITH THIS SYSTEM THAN THE ECMWF...BUT GIVEN
THE PATTERN IN PLACE AT THAT POINT...THE GFS FORECAST SEEMS MORE
REASONABLE. POPS ARE QUESTIONABLE WITH THIS SYSTEM...SO HAVE JUST
INDICATED LOW CHC POPS IN THE WEST FOR NOW UNTIL BETTER CONSENSUS IS
OBTAINED FROM THE MODELS ON THIS SYSTEM. BEYOND THAT...THE UPPER
FLOW BECOMES MORE ZONAL AND THE FOCUS WILL BE ON A HIGHLY
KINEMATIC...PACIFIC BASED SYSTEM IN THE SOUTHERN STREAM EXPECTED TO
REACH THE CWA AT THE END OF THE FORECAST PERIOD. THIS COULD BE A
SEVERE WEATHER SYSTEM FOR THE SOUTHERN PLAINS TO THE SOUTHEAST
STATES...BUT MORE QUESTIONABLE FOR OUR AREA. YIELDED TOWARD THE
SUPERBLEND FOR POPS IN THE LAST TWO PERIODS TO BETTER AGREE WITH
NEIGHBORS. HOWEVER...TIMING OF THE ARRIVAL OF WARM ADVECTION
PRECIPITATION ASSOCIATED WITH THIS SYSTEM REMAINS HIGHLY
QUESTIONABLE AT THIS POINT. THE ZONAL FLOW WILL YIELD TO NEAR NORMAL
TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 720 AM EDT THURSDAY...
RADAR SHOWED CLUSTER OF SHOWERS AND ISOLATED THUNDERSTORMS IN
SOUTH CENTRAL VIRGINIA MOVING NORTH THIS MORNING. SHOWERS WILL BE
OUT OF THE KLYH BY 13Z/9AM. BUFKIT FORECAST SHOWED CEILINGS
LOWERING TO IFR EARLY THIS MORNING UNDER A SHALLOW BUT STRONG
INVERSION. PERSISTENT WEDGE AND INVERSION WILL BREAK THIS
MORNING. MEDIUM CONFIDENCE THAT CEILINGS WILL IMPROVE BACK TO VFR
AT KROA/KBCB/KDAN AND KLYH BY 17Z/NOON. WINDS WILL BE GUSTY OUT OF
THE SOUTHWEST ONCE THE WEDGE ERODES.
HIGH CONFIDENCE THAT A STRONG COLD FRONT WILL CROSS THROUGH THE
REGION JUST AFTER 00Z/7PM AT KLWB AND KBLF. THE FRONT IS EXPECTED
TO REACH KLYH AROUND 04Z/MIDNIGHT AND KDAN AROUND 05Z/1AM. EXPECT
A BAND OF MODERATE TO HEAVY SHOWERS ALONG AND JUST BEHIND THE
FRONT. VISIBILITY MAY DROP TO MVFR LEVELS IN THE HEAVIER RAIN.
WINDS WILL BECOME NORTHWEST BEHIND THE FRONT WITH GUSTS AT 20 TO
30 KNOTS.
SHOWERS AND GUSTY WINDS WILL CONTINUE THROUGH FRIDAY AS MUCH
COLDER AIR SURGES INTO THE REGION. SNOW SHOWERS ARE LIKELY WITH
MVFR CEILINGS AND VISIBILITIES IN THE WESTERN UPSLOPE AREAS OF THE
MOUNTAINS LATE TONIGHT THROUGH FRIDAY NIGHT. WINDS WILL DIMINISH
SATURDAY WITH VFR CONDITIONS AS HIGH PRESSURE BUILDS INTO THE
AREA. VFR WEATHER IS EXPECTED SUNDAY AND MONDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/RCS
SHORT TERM...MBS
LONG TERM...RAB
AVIATION...AMS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1018 AM CDT THU MAR 26 2015
.AVIATION/18Z TAFS/...VERY CHILLY UPPER TROUGH ACROSS THE WESTERN
GREAT LAKES WITH 500 MILLIBAR TEMPS AROUND -30C. KGRB 12Z
SOUNDING SHOWS BASE OF STRONG INVERSION AROUND 800 MILLIBARS WITH
MOISTURE IN THE 800-850 MILLIBAR LAYER. SOUNDING HAS THE
INVERTED-V APPEARANCE. RAP SOUNDINGS SHOWS CIG HGTS MOSTLY AOA
MVFR LEVELS THOUGH SOME MVFR UPSTREAM IN NRN WI. SOME DECREASE IN
LLVL RH NOTED TONIGHT THOUGH 500 MILLIBAR TROUGH AXIS DOES NOT
SHIFT SE OF WI UNTIL AFTER 12Z FRIDAY. WILL KEEP SHSN CHCS NEAR
KMKE TAF TNGT WITH FAVORABLE ONSHORE FLOW DEVELOPING FOR A
TIME...ESP BLOW 850 MILLIBARS. HIGH PRESSURE BUILDS IN ESP FRI
AFTN FOR A GRADUAL DECREASE IN NORTHERLY LOW LEVEL FLOW.
PC
&&
.PREV DISCUSSION... /ISSUED 348 AM CDT THU MAR 26 2015/
TODAY...FORECAST CONFIDENCE IS MEDIUM.
BACK EDGE OF LOW CLOUD DECK HAS PUSHED INTO SW PORTIONS OF
FORECAST AREA...WITH MORE LOW CLOUDS UPSTREAM OVER NRN WI WITH
WEAK SHORT WAVE EMBEDDED IN CYCLONIC FLOW WITH DEEPENING 50 MB
TROUGH.
BIG QUESTION IS WHETHER THIS UPSTREAM CLOUD DECK WILL SETTLE OVER
SRN WI TODAY WITH COLD ADVECTION ON GUSTY NW WINDS BEHIND A
SECONDARY TROUGH...AND HOW SOON. MOS GUIDANCE AND SREF PROBABILITY
FORECASTS INDICATE LOWER DECK DROPPING INTO AREA MID-LATE MORNING.
WILL GO PESSIMISTIC WITH CLOUD COVER WHICH WILL HOLD TEMPS IN THE
UPPER 30S MOST LOCATIONS...EXCEPT FOR A FEW 40 DEGREE READINGS IN
THE SW CWA WITH A BIT OF MORNING SUN.
TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
COLD ADVECTION CONTINUES WITH 925 MB COLD POOL BRINGING LOWS IN
THE TEENS TONIGHT. DELTA T/S AND EQUILIBRIUM LEVELS OF 6K TO 7K
FEET BRING A POTENTIAL OF LAKE EFFECT SNOW SHOWERS/FLURRIES...WITH
NORTH FETCH LIMITS POTENTIAL OVER LAND TO LOCATIONS RIGHT NEAR THE
SHORE. WILL KEEP POPS IN THE SLIGHT CHANCE CATEGORY.
SHORT TERM...FRIDAY THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE
IS HIGH.
MODELS ARE IN GOOD AGREEMENT WITH HIGH PRESSURE SLIDING SLOWLY
SOUTHEASTWARD ACROSS THE NORTHERN GREAT LAKES REGION FRIDAY INTO
SATURDAY. THE HIGH WILL BRING QUIET WEATHER TO THE AREA. ONSHORE
LOW LEVEL WINDS FRIDAY NIGHT INTO EARLY SATURDAY WITH FAVORABLE
DELTA T VALUES ARE EXPECTED NEAR LAKE MICHIGAN. HOWEVER...DRY
AIRMASS IN PLACE SUGGESTS THAT ONLY A FEW CLOUDS A WORST SHOULD
OCCUR. TEMPERATURES WILL REMAIN BELOW SEASONAL NORMALS DURING THIS
PERIOD.
STRONG WARM AIR ADVECTION THEN OCCURS SATURDAY NIGHT ACROSS THE
REGION...AHEAD OF APPROACHING COLD FRONT. AREA FORECAST SOUNDINGS
SHOW MIDDLE TO HIGH CLOUDS INCREASING...WITH THE DEEPEST MOISTURE
IN THE FAR WESTERN COUNTIES. GFS ONLY MODEL TO BRING IN LIGHT QPF
BEFORE 12Z SUNDAY IN THIS AREA. WILL KEEP LOW END POPS IN THIS
AREA FOR NOW...THOUGH MAY BE ABLE TO HOLD OFF IN LATER FORECASTS.
BREEZY SOUTH WINDS DEVELOP AS WELL SATURDAY NIGHT.
LONG TERM...SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF SHOWING SOMEWHAT SIMILAR TRENDS WITH COLD FRONT/500 MB
SHORTWAVE TROUGH PASSAGE SUNDAY. GFS IS ABOUT 6 HOURS QUICKER
THAN THE ECMWF WITH THE PASSAGE OF THESE FEATURES...AND THE ECMWF
KEEPS SOME QPF IN THE FAR EAST SUNDAY EVENING. BOTH DO SHOW A
FAIRLY STRONG SHORTWAVE TROUGH. GFS KEEPS BEST QPF AND UPWARD
VERTICAL MOTION NORTH OF THE AREA...WITH THE ECMWF BRINGING A
SOLID AREA OF UPWARD VERTICAL MOTION AND QPF THROUGH THE AREA.
FOR NOW...WILL CONTINUE WITH THE CHANCE POPS FOR SUNDAY...AND IN
THE FAR EAST SUNDAY EVENING. MAY SEE A RAIN/SNOW MIX EARLY SUNDAY
MORNING BEFORE MILDER TEMPERATURES OCCUR.
MODELS THEN DIFFER WITH THE MONDAY NIGHT PERIOD. THE ECMWF BRINGS
A LOW WITH A STRONG 500 MB VORTICITY MAXIMUM THROUGH THE AREA WITH
SOME QPF. THE GFS IS DRY DURING THIS TIME. KEPT LOW END POPS FOR
LATER MONDAY INTO MONDAY NIGHT FOR NOW.
THEY ARE IN BETTER AGREEMENT WITH WARM AIR ADVECTION TUESDAY INTO
WEDNESDAY...AHEAD OF ANOTHER APPROACHING COLD FRONT. THE FRONT AND
ASSOCIATED QPF MOVES INTO THE AREA WEDNESDAY. KEPT CONSENSUS MODEL
POPS FOR THIS PERIOD. MILDER TEMPERATURES SHOULD OCCUR AS WELL.
AVIATION/12Z TAFS/...WITH SOME CLEARING OF STRATUS DECK INTO SW
PORTIONS OF FORECAST...THE BIG QUESTION IS WHETHER UPSTREAM
VFR/MVFR CLOUD DECK WILL SETTLE OVER SRN WI TODAY WITH COLD
ADVECTION ON GUSTY NW WINDS WITH A SECONDARY TROUGH...AND HOW
SOON. MOS GUIDANCE AND SREF PROBABILITY FORECASTS INDICATE LOWER
DECK DROPPING INTO AREA MID-LATE MORNING. WILL ADJUST FOR INITIAL
CLEARING AT ISSUANCE TIME...BUT OVERALL WILL GO PESSIMISTIC WITH
CLOUD COVER BUT KEEP IT AT VFR LEVELS.
NORTHWEST WINDS WILL SHIFT TO THE NORTH THIS EVENING BEHIND COLD
FRONT/SURFACE TROUGH. CONDITIONS FAVORABLE FOR DEVELOPMENT OF
LAKE-EFFECT SNOW SHOWERS...THOUGH MOST GUIDANCE KEEPING IT OUT
OVER THE LAKE. A SLIGHT CHANCE FOR KMKE...AND POSSIBLY KENW TO BE
BRUSHED BY SCATTERED LIGHT SNOW SHOWERS OR FLURRIES BETWEEN 03Z
AND 09Z BUT TOO LOW A PROBABILITY TO ADD TO TAFS AT THIS TIME.
MARINE...NORTHWEST WINDS WILL INCREASE THIS MORNING...WITH GUSTS
TO 20 KNOTS...BUT WITH OFFSHORE FETCH LIMITING WAVE HEIGHTS
CONDITIONS WILL REMAIN BELOW SMALL CRAFT LEVELS. A SMALL CRAFT
ADVISORY WILL LIKELY BE NEEDED TONIGHT THROUGH FRIDAY AS WINDS
SHIFT TO THE NORTH WITH GUSTS NEARING CRITERIA TONIGHT WITH
PASSAGE OF COLD FRONT/SURFACE TROUGH. NORTH FETCH WILL BUILD WAVES
TO 4 TO 6 FEET OVERNIGHT THROUGH FRIDAY...THEN SUBSIDE FRIDAY
NIGHT WITH EASING WINDS LATE FRIDAY AFTERNOON AND EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
FRIDAY THROUGH WEDNESDAY...WOOD
AREA FORECAST DISCUSSION
NWS ALBANY NY
126 PM EDT THU MAR 26 2015
.SYNOPSIS...
A LOW PRESSURE WILL DRAG A COLD FRONT ACROSS THE REGION
WHICH WILL ALLOW FOR RAIN TO DEVELOP DURING THE AFTERNOON. A RUMBLE
OF THUNDER IS POSSIBLE. AS THE COLD FRONT MOVES SOUTH OF THE
REGION...THE RAIN WILL MIX WITH THEN CHANGE TO SNOW OVER THE HIGHER
BY THIS EVENING INTO TONIGHT. SOME LIGHT ACCUMULATING SNOW WILL BE
POSSIBLE FOR MOST HIGHER TERRAIN AREAS TONIGHT. COLDER WEATHER WILL
ONCE AGAIN BE IN PLACE FOR FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1245 PM A GRAY DAMP DAY CONTINUES. SHOWERS WERE MAINLY
CONCENTRATED JUST NORTHWEST OF I-88 AND INTO THE ADIRONDACKS AND
LAKE GEORGE SARATOGA REGION. THERE WERE EVEN CLOUD TO CLOUD
LIGHTNING STRIKES JUST TO WEST OF SCHOHARIE VALLEY...AS THE
SHOWALTER INDEX WAS 0 OR LESS FROM I-88 SOUTHWARD.
CLOUDS HAVE FILLED IN EVERYWHERE AND WILL REMAIN THAT WAY FOR THE
REST OF TODAY.
LOW PRESSURE WAS WORKING INTO SW PA...ALONG A SLOW MOVING COLD FRONT
ACROSS CENTRAL PA AND NW NY. AS THESE BOTH COME CLOSER TO OUR
REGION...RAIN WILL BLOSSOM OVER THE REGION...WITH THE POSSIBILITY OF
A FEW EMBEDDED THUNDERSTORMS FROM THE CAPITAL REGION SOUTH. SOME OF
THE RAIN COULD HEAVY.
FOR THIS UPDATE...JUST FINE TUNED POPS BASED ON RADARS...LEAVING
HIGH TEMPERATURES ALONE. OUR AREA WILL NEVER GET INTO THE REALLY
WARM AIR THAT WAS WORKING UP THE DELMARVA PENNISULA TOWARD NEW
JERSEY. THAT WARM AIR WILL PROBABLY END UP SHORT OF NYC LET ALONE
OUR AREA.
OTHERWISE NO REAL CHANGE.
THE LATEST 3KM HRRR SHOWS WILL RAPIDLY ADVANCE INTO THE AREA FROM
CNY...AS THE FRONTAL BOUNDARY LIFTS TOWARDS OUR REGION THIS
AFTERNOON.
THROUGH THE AFTERNOON...STEADY RAIN WILL EXPAND ACROSS THE ENTIRE
REGION...AS A FRONTAL BOUNDARY GRADUALLY WORKS FROM WEST TO EAST
TOWARDS THE AREA. THIS FRONT WILL BE SLOWED DUE TO A WAVE OF LOW
PRESSURE MOVING UP ALONG THE BOUNDARY. TEMPS WILL START FALLING
ACROSS NORTHWESTERN AREAS BY LATE THIS AFTN...BUT SHOULD BE MILDER
COMPARED TO PREVIOUS DAYS ACROSS FAR SOUTHERN AREAS...WHERE TEMPS
MAY GET CLOSE TO 50. ELSEWHERE...EXPECT TEMPS ONLY IN THE UPPER 30S
TO MID 40S.
BY EARLY THIS EVENING...THE FRONT WILL BE WORKING ACROSS OUR
AREA...AND THE HEAVIEST PRECIP WILL BE OCCURRING JUST ALONG/AHEAD
OF THIS BOUNDARY. WITH SOME ELEVATED INSTABILITY IN PLACE
/SHOWALTER VALUES AT OR SLIGHTLY BELOW ZERO/ THERE MAY BE A RUMBLE
OF THUNDER ACROSS ULSTER....DUTCHESS...OR LITCHFIELD COUNTIES. AT
THE SAME TIME...RAIN WILL BE STARTING TO TRANSITION TO SNOW ACROSS
THE WESTERN ADIRONDACKS...AS COLDER AIR POURS INTO THE REGION
BEHIND THE FRONTAL BOUNDARY FROM CANADA.
ABOUT A HALF TO THREE QUARTER OF AN INCH OF RAIN IS POSSIBLE
THROUGH THIS EVENT TODAY. PLEASE SEE OUR HYDRO DISCUSSION ON HOW
WE EXPECT TODAY/S RAINFALL TO IMPACT OUR HYDRO SERVICE AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
TEMPERATURES WILL GRADUALLY COOL TONIGHT FROM NORTHWEST TO
SOUTHEAST ACROSS THE REGION...WHICH COULD ALLOW FOR A RAIN/SNOW
MIX EVEN IN THE VALLEYS LATE TONIGHT INTO EARLY FRIDAY MORNING.
THE SURFACE LOW IS FORECAST TO PULL AWAY FROM THE REGION ON
FRIDAY...HOWEVER AN UPPER LEVEL TROUGH IS FORECAST TO GRADUALLY
TRACK FROM THE GREAT LAKES INTO THE NORTHEAST FRIDAY INTO EARLY
SATURDAY. THIS WILL LEAD TO ISOLATED TO SCATTERED RAIN/SNOW
SHOWERS WITH MAINLY CLOUDY SKIES AND TEMPS BELOW NORMAL.
EXPECT LOWS TONIGHT TO RANGE FROM THE MID 20S NORTHWEST TO THE
UPPER 30S SOUTHEAST WITH HIGHS ON FRIDAY IN THE MID 30S TO UPPER
40S. LOWS FRIDAY NIGHT ARE EXPECTED TO BE IN THE SINGLE DIGITS
NORTHWEST TO MID 20S SOUTHEAST.
ON SATURDAY THE UPPER LEVEL TROUGH AXIS AND ASSOCIATED VORT MAX
SWINGS THROUGH THE FA. THIS WILL RESULT IN MAINLY WIDELY SCATTERED
TO SCATTERED SNOW SHOWERS. HIGHS ON SATURDAY ARE EXPECTED TO BE IN THE
MID 20S TO MID 30S. SATURDAY NIGHT IS EXPECTED TO BE CLEAR AND
COLD AS A RIDGE OF HIGH PRESSURE BUILDS SOUTHEAST FROM THE CENTRAL
GREAT LAKES TO THE TENNESSEE VALLEY. LOWS SATURDAY NIGHT ARE
EXPECTED TO RANGE FROM THE SINGLE DIGITS NORTHWEST TO UPPER TEENS
SOUTHEAST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE EXTENDED FORECAST FEATURES A FAIRLY PERSISTENT MEAN LONGWAVE
TROUGH OVER THE NORTHEAST AND SOUTHEASTERN CANADA WITH A FEW
DISTURBANCES IN THE W/NW FLOW BRINGING SOME RAIN AND SNOW SHOWERS TO
THE REGION.
SUNDAY...THE WEEKEND CLOSES WITH SFC HIGH PRESSURE RIDGING IN FROM
THE MID ATLANTIC REGION. THE UPPER LEVEL TROUGH MOVES OFFSHORE.
THERE WAS GOOD AGREEMENT WITH THE GFS/GEFS/ECMWF/WPC GUIDANCE HERE.
H850 TEMPS WILL BE A LITTLE BELOW NORMAL IN THE -4C TO -7C RANGE.
THE SUBSIDENCE FROM THE SFC ANTICYCLONE WILL PROVIDE PLENTY OF
SUNSHINE WITH TEMPS RUNNING ABOUT 5 TO 10 DEGREES BELOW NORMAL.
HIGHS WILL RANGE FROM THE U30S TO M40S IN THE VALLEYS...AND 30S OVER
THE MTNS.
SUNDAY NIGHT INTO MONDAY...A PROGRESSIVE UPPER LEVEL TROUGH
APPROACHES FROM THE ONTARIO...THE GREAT LAKES REGION...AND THE
MIDWEST SUNDAY NIGHT. CLOUDS INCREASE OVERNIGHT WITH THE CLIPPER
TYPE LOW TRACKING TOWARDS THE REGION. THE SYSTEMS COLD FRONT WILL
REACH THE ST LAWRENCE RIVER VALLEY TOWARDS DAYBREAK ON MONDAY.
INITIALLY WEAK ISENTROPIC LIFT AHEAD OF THE SYSTEM MAY KICK OFF SOME
SCT SNOW SHOWERS...ESPECIALLY FROM THE CAPITAL REGION NORTH AND
WEST. SOME LIGHT ACCUMULATIONS WILL BE POSSIBLE. SOME OF THE SNOW SHOWERS
MAY EVEN REACH THE HUDSON RIVER VALLEY EARLY ON. THE PCPN WILL
LIKELY TRANSITION TO A MIXTURE OF RAIN AND SNOW SHOWERS AS THE
BOUNDARY LAYER WARMS DUE TO S TO SW FLOW ALOFT. EXPECT SEASONABLE
AND BREEZY CONDITIONS. THE COLD FRONT WILL BE POISED TO MOVE
THROUGH TOWARDS THE LATE AFTERNOON. AFTER LOWS IN THE 20S TO AROUND
30F IN THE MID HUDSON VALLEY...EXPECT HIGHS TO REACH THE 40S TO L50S
IN THE VALLEYS...AND U30S TO L40S OVER THE HIGHER ELEVATIONS.
MONDAY NIGHT...THE COLD FRONT MOVES THROUGH WITH SCT SNOW SHOWERS
MAINLY NORTH AND WEST OF THE CAPITAL DISTRICT AND THE MID HUDSON
VALLEY. SOME W/NW UPSLOPE SNOW SHOWERS WILL LINGER ACROSS THE SRN
GREENS AND SRN DACKS. AGAIN...ANY ACCUMULATIONS LOOK VERY LIGHT. EXPECT
LOWS TO FALL BACK INTO THE 20S TO L30S IN THE COLD ADVECTION REGIME.
TUE-TUE NIGHT...ANOTHER CLIPPER LOW MAY DIVE S/SE ACROSS THE CNTRL
GREAT LAKES REGION...AND INTO PA LATE TUE PM INTO TUE NIGHT
ACCORDING TO THE ECMWF MISSING MOST OF THE FCST AREA. THE GFS WOULD
HAVE A SECONDARY COLD FRONT MOVING THROUGH WITH SOME ISOLD-SCT
UPSLOPE SNOW SHOWERS WITH HIGH PRESSURE BUILDING IN. WPC IS A
LITTLE CLOSER TO THE GFS. WE WENT MAINLY DRY TUESDAY INTO TUESDAY
NIGHT WITH COLD CONDITIONS FOR THE LAST DAY OF MARCH. THE GFS HAS
H850 TEMPS IN THE -9C TO -13C RANGE OVER THE FCST AREA. TEMPS WILL
RUN 5 OR MORE DEGREES BELOW NORMAL...AS HIGHS WILL BE IN THE 40S IN
THE VALLEYS...AND M30S TO AROUND 40 OVER THE HILLS AND MTNS.
OVERNIGHT LOWS WILL BE COLD IN THE 20S TO L30S WITH A FEW TEENS OVER
THE SRN DACK PARK.
WEDNESDAY...WEAK RIDGING ALOFT WILL START THE DAY...AND THEN ANOTHER
CLIPPER LIKE DISTURBANCE WILL APPROACH FROM THE GREAT LAKES REGION
LATE IN THE DAY. A SLIGHT OR LOW CHC OF RAIN/SNOW SHOWERS WAS KEPT
IN THE FCST PREDOMINANTLY WEST OF THE HUDSON RIVER VALLEY. TEMPS
WILL BE A LITTLE BELOW NORMAL TO START APRIL.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS A FRONTAL BOUNDARY MOVES ACROSS THE REGION THIS AFTN...FLYING
CONDITIONS WILL VARY BETWEEN MVFR AND IFR WITH PERIODS OF RAIN.
THERE MAY BE EVEN BE A RUMBLE OF THUNDER FOR KALB/KPOU/KPSF...BUT
CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE IN THE TAF AT THIS TIME.
ALTHOUGH WINDS WILL BEGIN SOUTHERLY AT 5-10 KTS...THEY WILL SWITCH
TO N-NW BY THE EVENING HOURS...AS THE FRONTAL BOUNDARY MOVES FROM
WEST TO EAST ACROSS THE AREA.
STEADY RAIN SHOULD TAPER TO SHOWERS IN THE LATE EVENING AND END
DURING THE OVERNIGHT HOURS. THIS WILL ALLOW FLYING CONDITIONS TO
IMPROVE INITIALLY TO MVFR...AND EVENTUALLY VFR. IT MAY TAKE THE
LONGEST TO RETURN TO VFR AT KPSF/KPOU...WHERE THE RAIN SHOWERS
WILL LINGER THE LONGEST...AS THE FRONT MOVES EASTWARD OVERNIGHT.
WINDS OVERNIGHT WILL GENERALLY BE N-NW AT AROUND 5 KTS.
ON FRIDAY...FLYING CONDITIONS WILL MAINLY BE VFR...WITH CONTINUED
BKN CIGS AROUND 3500-5000 FT. CANNOT TOTALLY RULE OUT A BRIEF RAIN
SHOWERS...BUT MOST AREAS LOOK TO BE DRY FOR MOST OF THE TIME.
WINDS WILL BE W-NW AT 5-10 KTS.
OUTLOOK...
FRIDAY NIGHT-SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE
-SHSN.
SATURDAY NIGHT-SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY-MONDAY EVENING: LOW OPERATIONAL IMPACT. CHC -SHSN/-SHRA.
MONDAY LATE NIGHT-TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
FIRE WEATHER ISSUES ARE NOT ANTICIPATED OVER THE NEXT SEVERAL DAYS
WITH SNOW COVER IN PLACE ACROSS MUCH OF THE REGION...AND WET/
UNSETTLED WEATHER FORECAST INTO FRIDAY.
AFTER A BRIEF BREAK IN THE PRECIPITATION EARLY TODAY...A
LOW PRESSURE SYSTEM AND ITS COLD FRONT WILL ALLOW FOR WIDESPREAD
RAIN TO DEVELOP BY THIS AFTERNOON. AS THE COLD FRONT MOVES SOUTH OF
THE REGION...THE RAIN WILL MIX WITH THEN CHANGE TO SNOW OVER THE
HIGHER TERRAIN MAINLY NORTH AND WEST OF THE CAPITAL DISTRICT TODAY
INTO THIS EVENING. SOME LIGHT ACCUMULATING SNOW WILL BE POSSIBLE FOR
MOST HIGHER TERRAIN AREAS TONIGHT. COLDER WEATHER WILL ONCE AGAIN BE
IN PLACE FOR FRIDAY INTO THE WEEKEND.
&&
.HYDROLOGY...
WIDESPREAD HYDRO ISSUES ARE NOT EXPECTED THROUGH THE NEXT 5
DAYS...ALTHOUGH A FEW RIVER POINTS MAY GET CLOSE TO BANKFULL OVER
THE NEXT COUPLE DAY DUE TO RAINFALL AND SOME SNOWMELT. ALSO ISOLATED
ICE JAMS WILL BE POSSIBLE ACROSS THE SOUTHEAST HALF OF THE HYDRO
SERVICE AREA.
ON THURSDAY...MILDER AIR WITH DEWPOINTS CLIMBING INTO THE 40S
MAINLY SOUTH OF I-90... ALONG WITH RAINFALL IN THE HALF AN INCH TO
THREE QUARTERS OF AN INCH RANGE...WILL PRODUCE SOME MELTING OF
THE SNOW...AND POTENTIALLY ICE BREAKUP ON THE RIVERS.
THE LATEST MMEFS GUIDANCE INCLUDING THE NAEFS...GEFS...AND SERFS NOW
INDICATE NO RIVER POINTS FORECAST TO REACH FLOOD STAGE. THE LATEST
NERF FORECASTS SHOW ABOUT 4 POINTS GETTING TO THE ALERT STAGE EAST
OF THE HUDSON RIVER VALLEY...BUT NO FLOODING AT THIS TIME.
CONFIDENCE CONTINUES TO BE LOW FOR THE POTENTIAL OF WIDESPREAD
FLOODING...SO NO WATCH HAS BEEN ISSUED AT THIS TIME.
THE MOST LIKELY TIME FRAME FOR ANY POTENTIAL PROBLEMS WOULD BE
THURSDAY EVENING FOR SMALL STREAMS...AND NOT UNTIL FRIDAY FOR THE
CRESTING OF THE BIGGER RIVERS. BY THAT TIME...TEMPERATURES ACROSS
THE ADIRONDACKS WILL BE AT OR BELOW FREEZING. NO SIGNIFICANT
PROBLEMS ARE EXPECTED ACROSS THE NORTHERN TIER OF THE HYDRO SERVICE
AREA...AS MUCH OF THE RAIN WILL SOAK OR BE ABSORBED INTO THE
SNOWFALL...AND THE RAIN WILL CHANGE TO SNOW LATE THURSDAY INTO
THURSDAY NIGHT.
THE POTENTIAL ALSO EXISTS FOR ISOLATED ICE JAMS THURSDAY INTO
FRIDAY...AS ICE BREAKS UP MAY OCCUR ON SOME RIVERS AND
STREAMS...PARTICULARLY FROM THE CAPITAL DISTRICT SOUTH AND EAST
WHERE ICE STILL EXISTS. THIS WILL BE MONITORED OVER THE NEXT COUPLE
OF DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/HWJIV/11/JPV
NEAR TERM...FRUGIS/HWJIV
SHORT TERM...11/JPV
LONG TERM...WASULA
AVIATION...FRUGIS
FIRE WEATHER...11
HYDROLOGY...11/JPV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1245 PM EDT THU MAR 26 2015
.SYNOPSIS...
A LOW PRESSURE WILL DRAG A COLD FRONT ACROSS THE REGION
WHICH WILL ALLOW FOR RAIN TO DEVELOP DURING THE AFTERNOON. A RUMBLE
OF THUNDER IS POSSIBLE. AS THE COLD FRONT MOVES SOUTH OF THE
REGION...THE RAIN WILL MIX WITH THEN CHANGE TO SNOW OVER THE HIGHER
BY THIS EVENING INTO TONIGHT. SOME LIGHT ACCUMULATING SNOW WILL BE
POSSIBLE FOR MOST HIGHER TERRAIN AREAS TONIGHT. COLDER WEATHER WILL
ONCE AGAIN BE IN PLACE FOR FRIDAY INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1245 PM A GRAY DAMP DAY CONTINUES. SHOWERS WERE MAINLY
CONCENTRATED JUST NORTHWEST OF I-88 AND INTO THE ADIRONDACKS AND
LAKE GEORGE SARATOGA REGION. THERE WERE EVEN CLOUD TO CLOUD
LIGHTNING STRIKES JUST TO WEST OF SCHOHARIE VALLEY...AS THE
SHOWALTER INDEX WAS 0 OR LESS FROM I-88 SOUTHWARD.
CLOUDS HAVE FILLED IN EVERYWHERE AND WILL REMAIN THAT WAY FOR THE
REST OF TODAY.
LOW PRESSURE WAS WORKING INTO SW PA...ALONG A SLOW MOVING COLD FRONT
ACROSS CENTRAL PA AND NW NY. AS THESE BOTH COME CLOSER TO OUR
REGION...RAIN WILL BLOSSOM OVER THE REGION...WITH THE POSSIBILITY OF
A FEW EMBEDDED THUNDERSTORMS FROM THE CAPITAL REGION SOUTH. SOME OF
THE RAIN COULD HEAVY.
FOR THIS UPDATE...JUST FINE TUNED POPS BASED ON RADARS...LEAVING
HIGH TEMPERATURES ALONE. OUR AREA WILL NEVER GET INTO THE REALLY
WARM AIR THAT WAS WORKING UP THE DELMARVA PENNISULA TOWARD NEW
JERSEY. THAT WARM AIR WILL PROBABLY END UP SHORT OF NYC LET ALONE
OUR AREA.
OTHERWISE NO REAL CHANGE.
THE LATEST 3KM HRRR SHOWS WILL RAPIDLY ADVANCE INTO THE AREA FROM
CNY...AS THE FRONTAL BOUNDARY LIFTS TOWARDS OUR REGION THIS
AFTERNOON.
THROUGH THE AFTERNOON...STEADY RAIN WILL EXPAND ACROSS THE ENTIRE
REGION...AS A FRONTAL BOUNDARY GRADUALLY WORKS FROM WEST TO EAST
TOWARDS THE AREA. THIS FRONT WILL BE SLOWED DUE TO A WAVE OF LOW
PRESSURE MOVING UP ALONG THE BOUNDARY. TEMPS WILL START FALLING
ACROSS NORTHWESTERN AREAS BY LATE THIS AFTN...BUT SHOULD BE MILDER
COMPARED TO PREVIOUS DAYS ACROSS FAR SOUTHERN AREAS...WHERE TEMPS
MAY GET CLOSE TO 50. ELSEWHERE...EXPECT TEMPS ONLY IN THE UPPER 30S
TO MID 40S.
BY EARLY THIS EVENING...THE FRONT WILL BE WORKING ACROSS OUR
AREA...AND THE HEAVIEST PRECIP WILL BE OCCURRING JUST ALONG/AHEAD
OF THIS BOUNDARY. WITH SOME ELEVATED INSTABILITY IN PLACE
/SHOWALTER VALUES AT OR SLIGHTLY BELOW ZERO/ THERE MAY BE A RUMBLE
OF THUNDER ACROSS ULSTER....DUTCHESS...OR LITCHFIELD COUNTIES. AT
THE SAME TIME...RAIN WILL BE STARTING TO TRANSITION TO SNOW ACROSS
THE WESTERN ADIRONDACKS...AS COLDER AIR POURS INTO THE REGION
BEHIND THE FRONTAL BOUNDARY FROM CANADA.
ABOUT A HALF TO THREE QUARTER OF AN INCH OF RAIN IS POSSIBLE
THROUGH THIS EVENT TODAY. PLEASE SEE OUR HYDRO DISCUSSION ON HOW
WE EXPECT TODAY/S RAINFALL TO IMPACT OUR HYDRO SERVICE AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
TEMPERATURES WILL GRADUALLY COOL TONIGHT FROM NORTHWEST TO
SOUTHEAST ACROSS THE REGION...WHICH COULD ALLOW FOR A RAIN/SNOW
MIX EVEN IN THE VALLEYS LATE TONIGHT INTO EARLY FRIDAY MORNING.
THE SURFACE LOW IS FORECAST TO PULL AWAY FROM THE REGION ON
FRIDAY...HOWEVER AN UPPER LEVEL TROUGH IS FORECAST TO GRADUALLY
TRACK FROM THE GREAT LAKES INTO THE NORTHEAST FRIDAY INTO EARLY
SATURDAY. THIS WILL LEAD TO ISOLATED TO SCATTERED RAIN/SNOW
SHOWERS WITH MAINLY CLOUDY SKIES AND TEMPS BELOW NORMAL.
EXPECT LOWS TONIGHT TO RANGE FROM THE MID 20S NORTHWEST TO THE
UPPER 30S SOUTHEAST WITH HIGHS ON FRIDAY IN THE MID 30S TO UPPER
40S. LOWS FRIDAY NIGHT ARE EXPECTED TO BE IN THE SINGLE DIGITS
NORTHWEST TO MID 20S SOUTHEAST.
ON SATURDAY THE UPPER LEVEL TROUGH AXIS AND ASSOCIATED VORT MAX
SWINGS THROUGH THE FA. THIS WILL RESULT IN MAINLY WIDELY SCATTERED
TO SCATTERED SNOW SHOWERS. HIGHS ON SATURDAY ARE EXPECTED TO BE IN THE
MID 20S TO MID 30S. SATURDAY NIGHT IS EXPECTED TO BE CLEAR AND
COLD AS A RIDGE OF HIGH PRESSURE BUILDS SOUTHEAST FROM THE CENTRAL
GREAT LAKES TO THE TENNESSEE VALLEY. LOWS SATURDAY NIGHT ARE
EXPECTED TO RANGE FROM THE SINGLE DIGITS NORTHWEST TO UPPER TEENS
SOUTHEAST.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE EXTENDED FORECAST FEATURES A FAIRLY PERSISTENT MEAN LONGWAVE
TROUGH OVER THE NORTHEAST AND SOUTHEASTERN CANADA WITH A FEW
DISTURBANCES IN THE W/NW FLOW BRINGING SOME RAIN AND SNOW SHOWERS TO
THE REGION.
SUNDAY...THE WEEKEND CLOSES WITH SFC HIGH PRESSURE RIDGING IN FROM
THE MID ATLANTIC REGION. THE UPPER LEVEL TROUGH MOVES OFFSHORE.
THERE WAS GOOD AGREEMENT WITH THE GFS/GEFS/ECMWF/WPC GUIDANCE HERE.
H850 TEMPS WILL BE A LITTLE BELOW NORMAL IN THE -4C TO -7C RANGE.
THE SUBSIDENCE FROM THE SFC ANTICYCLONE WILL PROVIDE PLENTY OF
SUNSHINE WITH TEMPS RUNNING ABOUT 5 TO 10 DEGREES BELOW NORMAL.
HIGHS WILL RANGE FROM THE U30S TO M40S IN THE VALLEYS...AND 30S OVER
THE MTNS.
SUNDAY NIGHT INTO MONDAY...A PROGRESSIVE UPPER LEVEL TROUGH
APPROACHES FROM THE ONTARIO...THE GREAT LAKES REGION...AND THE
MIDWEST SUNDAY NIGHT. CLOUDS INCREASE OVERNIGHT WITH THE CLIPPER
TYPE LOW TRACKING TOWARDS THE REGION. THE SYSTEMS COLD FRONT WILL
REACH THE ST LAWRENCE RIVER VALLEY TOWARDS DAYBREAK ON MONDAY.
INITIALLY WEAK ISENTROPIC LIFT AHEAD OF THE SYSTEM MAY KICK OFF SOME
SCT SNOW SHOWERS...ESPECIALLY FROM THE CAPITAL REGION NORTH AND
WEST. SOME LIGHT ACCUMULATIONS WILL BE POSSIBLE. SOME OF THE SNOW SHOWERS
MAY EVEN REACH THE HUDSON RIVER VALLEY EARLY ON. THE PCPN WILL
LIKELY TRANSITION TO A MIXTURE OF RAIN AND SNOW SHOWERS AS THE
BOUNDARY LAYER WARMS DUE TO S TO SW FLOW ALOFT. EXPECT SEASONABLE
AND BREEZY CONDITIONS. THE COLD FRONT WILL BE POISED TO MOVE
THROUGH TOWARDS THE LATE AFTERNOON. AFTER LOWS IN THE 20S TO AROUND
30F IN THE MID HUDSON VALLEY...EXPECT HIGHS TO REACH THE 40S TO L50S
IN THE VALLEYS...AND U30S TO L40S OVER THE HIGHER ELEVATIONS.
MONDAY NIGHT...THE COLD FRONT MOVES THROUGH WITH SCT SNOW SHOWERS
MAINLY NORTH AND WEST OF THE CAPITAL DISTRICT AND THE MID HUDSON
VALLEY. SOME W/NW UPSLOPE SNOW SHOWERS WILL LINGER ACROSS THE SRN
GREENS AND SRN DACKS. AGAIN...ANY ACCUMULATIONS LOOK VERY LIGHT. EXPECT
LOWS TO FALL BACK INTO THE 20S TO L30S IN THE COLD ADVECTION REGIME.
TUE-TUE NIGHT...ANOTHER CLIPPER LOW MAY DIVE S/SE ACROSS THE CNTRL
GREAT LAKES REGION...AND INTO PA LATE TUE PM INTO TUE NIGHT
ACCORDING TO THE ECMWF MISSING MOST OF THE FCST AREA. THE GFS WOULD
HAVE A SECONDARY COLD FRONT MOVING THROUGH WITH SOME ISOLD-SCT
UPSLOPE SNOW SHOWERS WITH HIGH PRESSURE BUILDING IN. WPC IS A
LITTLE CLOSER TO THE GFS. WE WENT MAINLY DRY TUESDAY INTO TUESDAY
NIGHT WITH COLD CONDITIONS FOR THE LAST DAY OF MARCH. THE GFS HAS
H850 TEMPS IN THE -9C TO -13C RANGE OVER THE FCST AREA. TEMPS WILL
RUN 5 OR MORE DEGREES BELOW NORMAL...AS HIGHS WILL BE IN THE 40S IN
THE VALLEYS...AND M30S TO AROUND 40 OVER THE HILLS AND MTNS.
OVERNIGHT LOWS WILL BE COLD IN THE 20S TO L30S WITH A FEW TEENS OVER
THE SRN DACK PARK.
WEDNESDAY...WEAK RIDGING ALOFT WILL START THE DAY...AND THEN ANOTHER
CLIPPER LIKE DISTURBANCE WILL APPROACH FROM THE GREAT LAKES REGION
LATE IN THE DAY. A SLIGHT OR LOW CHC OF RAIN/SNOW SHOWERS WAS KEPT
IN THE FCST PREDOMINANTLY WEST OF THE HUDSON RIVER VALLEY. TEMPS
WILL BE A LITTLE BELOW NORMAL TO START APRIL.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
A WARM FRONT WILL MOVE ACROSS ERN NY AND WRN NEW ENGLAND THIS
MORNING. A COLD FRONT WILL BECOME STATIONARY OVER EAST CENTRAL NY
AND NEW ENGLAND EARLY THIS AFTERNOON...AS LOW PRESSURE WILL MOVE
ALONG IT BRINGING PERIODS OF RAIN BACK INTO THE REGION. THE COLD
FRONT WILL SLOWLY MOVE S/SE ACROSS THE REGION LATE THURSDAY
AFTERNOON THROUGH THURSDAY NIGHT.
LOW STRATUS AND MIST/FOG HAS FORMED AT KGFL/KALB/KPSF/KPOU EARLY
THIS MORNING IN THE WARM ADVECTION ENVIRONMENT AHEAD OF THE WARM
FRONT. THE LOW STRATUS IS EXPECTED TO CONTINUE AT ALL THE
SITES...EXPECT WIDESPREAD IFR/LIFR CONDITIONS PRIOR TO 15Z. SOME
IMPROVEMENT TO IFR/HIGH MVFR IS POSSIBLE PRIOR TO ARRIVAL OF THE
RAINFALL AT 18Z. THE IMPROVEMENT WILL ONLY BE TEMPORARY AS THE
RAIN MOVES BACK IN PRODUCING WIDESPREAD IFR CONDITIONS AGAIN IN
TERMS OF CIGS AND VSBYS. THE MELTING SNOW WILL ALSO INCREASE THE
FOG POTENTIAL. THE CONDITIONS WILL CONTINUE AT IFR AND POSSIBLY
EVEN LIFR LEVELS AT KPSF AFTER 00Z/FRI.
THE PCPN MAY MIX WITH RAIN AND SNOW AS THE THE FRONT SAGS SOUTH
BTW 03Z-05Z...ESPECIALLY AT KGFL/KPOU...BUT THE CIGS AND VSBYS
SHOULD IMPROVE MVFR LEVELS AT ALL THE SITES.
EXPECT MAINLY VARIABLE IN DIRECTION WINDS IN THE LATE MORNING
INTO THE EARLY AFTERNOON AT 7 KTS OR LESS. THE WINDS WILL SHIFT TO
THE NE TO NW AT 5-10 KTS IN THE LATE AFTERNOON INTO THE EARLY
EVENING.
OUTLOOK...
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE RA/SN.
FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE SHRA.
FRIDAY NIGHT-SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE SHSN.
SATURDAY-MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
FIRE WEATHER ISSUES ARE NOT ANTICIPATED OVER THE NEXT SEVERAL DAYS
WITH SNOW COVER IN PLACE ACROSS MUCH OF THE REGION...AND WET/
UNSETTLED WEATHER FORECAST INTO FRIDAY.
AFTER A BRIEF BREAK IN THE PRECIPITATION EARLY TODAY...A
LOW PRESSURE SYSTEM AND ITS COLD FRONT WILL ALLOW FOR WIDESPREAD
RAIN TO DEVELOP BY THIS AFTERNOON. AS THE COLD FRONT MOVES SOUTH OF
THE REGION...THE RAIN WILL MIX WITH THEN CHANGE TO SNOW OVER THE
HIGHER TERRAIN MAINLY NORTH AND WEST OF THE CAPITAL DISTRICT TODAY
INTO THIS EVENING. SOME LIGHT ACCUMULATING SNOW WILL BE POSSIBLE FOR
MOST HIGHER TERRAIN AREAS TONIGHT. COLDER WEATHER WILL ONCE AGAIN BE
IN PLACE FOR FRIDAY INTO THE WEEKEND.
&&
.HYDROLOGY...
WIDESPREAD HYDRO ISSUES ARE NOT EXPECTED THROUGH THE NEXT 5
DAYS...ALTHOUGH A FEW RIVER POINTS MAY GET CLOSE TO BANKFULL OVER
THE NEXT COUPLE DAY DUE TO RAINFALL AND SOME SNOWMELT. ALSO ISOLATED
ICE JAMS WILL BE POSSIBLE ACROSS THE SOUTHEAST HALF OF THE HYDRO
SERVICE AREA.
ON THURSDAY...MILDER AIR WITH DEWPOINTS CLIMBING INTO THE 40S
MAINLY SOUTH OF I-90... ALONG WITH RAINFALL IN THE HALF AN INCH TO
THREE QUARTERS OF AN INCH RANGE...WILL PRODUCE SOME MELTING OF
THE SNOW...AND POTENTIALLY ICE BREAKUP ON THE RIVERS.
THE LATEST MMEFS GUIDANCE INCLUDING THE NAEFS...GEFS...AND SERFS NOW
INDICATE NO RIVER POINTS FORECAST TO REACH FLOOD STAGE. THE LATEST
NERF FORECASTS SHOW ABOUT 4 POINTS GETTING TO THE ALERT STAGE EAST
OF THE HUDSON RIVER VALLEY...BUT NO FLOODING AT THIS TIME.
CONFIDENCE CONTINUES TO BE LOW FOR THE POTENTIAL OF WIDESPREAD
FLOODING...SO NO WATCH HAS BEEN ISSUED AT THIS TIME.
THE MOST LIKELY TIME FRAME FOR ANY POTENTIAL PROBLEMS WOULD BE
THURSDAY EVENING FOR SMALL STREAMS...AND NOT UNTIL FRIDAY FOR THE
CRESTING OF THE BIGGER RIVERS. BY THAT TIME...TEMPERATURES ACROSS
THE ADIRONDACKS WILL BE AT OR BELOW FREEZING. NO SIGNIFICANT
PROBLEMS ARE EXPECTED ACROSS THE NORTHERN TIER OF THE HYDRO SERVICE
AREA...AS MUCH OF THE RAIN WILL SOAK OR BE ABSORBED INTO THE
SNOWFALL...AND THE RAIN WILL CHANGE TO SNOW LATE THURSDAY INTO
THURSDAY NIGHT.
THE POTENTIAL ALSO EXISTS FOR ISOLATED ICE JAMS THURSDAY INTO
FRIDAY...AS ICE BREAKS UP MAY OCCUR ON SOME RIVERS AND
STREAMS...PARTICULARLY FROM THE CAPITAL DISTRICT SOUTH AND EAST
WHERE ICE STILL EXISTS. THIS WILL BE MONITORED OVER THE NEXT COUPLE
OF DAYS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS/HWJIV/11/JPV
NEAR TERM...FRUGIS/HWJIV
SHORT TERM...11/JPV
LONG TERM...WASULA
AVIATION...WASULA
FIRE WEATHER...11
HYDROLOGY...11/JPV/WASULA
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
415 PM EDT THU MAR 26 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL WEAKEN AHEAD OF A STRONG COLD FRONT
APPROACHING TONIGHT AND SWEEPING THROUGH THE REGION FRIDAY.
COLDER HIGH PRESSURE WILL THEN BUILD FOR THE WEEKEND SUPPORTING A
POSSIBLE FREEZE FOR SOME INLAND AREAS EARLY SUNDAY. HIGH PRESSURE
THEN SHIFTS SOUTH OF THE REGION MONDAY...BEFORE ANOTHER COLD FRONT
MOVES THROUGH LATE MONDAY OR EARLY TUESDAY. HIGH PRESSURE WILL
THEN PREVAIL INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE AREA WILL REMAIN WELL WITHIN THE WARM SECTOR TONIGHT AHEAD OF
AN APPROACHING COLD FRONT. FAVORABLE UVM INDUCED BY THE RIGHT
ENTRANCE REGION OF A DEPARTING 250 HPA JET STREAK COUPLED WITH A
850 HPA 30-35 KT LOW-LEVEL JET AND RIBBON OF PWATS APPROACHING
1.50 INCHES WILL SUPPORT SOME SHOWER ACTIVITY OVERNIGHT...HOWEVER
IT IS UNCLEAR EXACTLY HOW WIDESPREAD THIS ACTIVITY WILL BECOME AS
EXTENSIVE CONVECTION ALONG THE GULF COAST IS FORECAST TO PERSIST
THROUGH THE NIGHT. THIS AREA OF CONVECTION WILL TEND TO DISRUPT
THE NECESSARY LOW-LEVEL INFLOW OF GULF MOISTURE INTO THE REGION
AHEAD OF THE FRONT...WHICH IS ALWAYS A PROBLEMATIC ELEMENT WHEN
FORECASTING PRECIPITATION FOR THE LOWCOUNTRY AND COASTAL EMPIRE.
BOTH THE 26/12Z GFS AND NAM WITH SUPPORT FROM THE LATEST SREF HAVE
PICKED UP ON THIS AND HAVE TRENDED DRIER FOR MUCH OF THE OVERNIGHT
PERIOD.
WILL LOWER POPS FOR TONIGHT ESPECIALLY DURING THE EVENING HOURS
WHERE LITTLE SIGNIFICANT SHOWER ACTIVITY IS EXPECTED...OUTSIDE OF
A FEW SHOWERS WHICH MAY BLEED INTO THE AREA FROM THE SOUTHWEST
PER LATEST KTLH/KVAX RADAR TRENDS. STILL EXPECT SCATTERED TO
PERHAPS NUMEROUS SHOWERS TO BREAK OUT JUST BEFORE SUNRISE AS THE
COLD FRONT DRAWS CLOSER AND LOW- LEVEL CONVERGENCE INCREASES...BUT
EVEN THIS MAY PROVE TO BE TOO QUICK IF MODELS CONTINUE TO TREND
SLOWER WITH THE PROGRESSION OF THE COLD FRONT. MAXIMUM POPS WILL
RANGE FROM 40-50 PERCENT AT THE COAST WITH 50-60 PERCENT INLAND.
LOWS WILL ONLY BOTTOM OUT IN THE LOWER 60S WITH A FEW UPPER 50S
ALONG THE BEACHES.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
FRIDAY...A SURFACE TROUGH WILL BE LOCATED ALONG THE MID ATLANTIC
AND SOUTHEAST COASTLINE BY DAYBREAK...WITH A STRONG COLD FRONT
STEADILY DESCENDING FROM THE UPSTATE REGION. THERE IS EVIDENCE OF
A DRY SLOT DEVELOPING ACROSS PORTIONS OF THE FORECAST AREA AHEAD
OF THE APPROACHING COLD FRONT DURING THE MORNING HOURS...LENDING
SOME UNCERTAINTY TO TIMING AND COVERAGE OF RAIN ASSOCIATED WITH
THE FRONTAL PASSAGE. CONSIDERING DEEP MOISTURE ACROSS THE
REGION...A STRONG MID/UPPER LEVEL JET INTENSIFYING OVER THE
AREA...AND DECENT CONVERGENCE ALONG THE FRONTAL ZONE...PREFER TO
INDICATE RAIN CHANCES INCREASING THROUGH THE MORNING HOURS INTO
THE LIKELY RANGE FOR MOST LOCATIONS. WILL ADVERTISE HIGHEST
POTENTIAL DURING THE LATE MORNING AND EARLY AFTERNOON...WITH
FAVORED LOCATIONS TO THE NORTH AND EAST...INCLUDING THE CHARLESTON
TRI COUNTY AND ALONG THE COASTLINE. RAIN CHANCES WILL THEN
DECREASE FROM WEST TO EAST LATER IN THE AFTERNOON...AS THE COLD
FRONT CROSSES THE FORECAST AREA AHEAD OF STRONG SHORTWAVE ENERGY
APPROACHING FROM THE WEST. HIGH TEMPERATURES ON FRIDAY WILL LIKELY
BE REACHED BY EARLY AFTERNOON...WITH A COOLING TREND INTO LATE
AFTERNOON. TEMPERATURES WILL PEAK IN THE MID 60S NORTH TO THE LOW
70S SOUTH.
FRIDAY NIGHT...THE COLD FRONT WILL RAPIDLY EXIT THE COASTLINE AND
PROCEED INTO THE ATLANTIC DURING THE EVENING HOURS...WITH STRONG
SURFACE HIGH PRESSURE BUILDING IN ITS WAKE. NORTHERN AND SOUTHERN
STREAM ENERGY WILL MERGE INTO AN AMPLIFYING UPPER TROUGH THAT
SHIFTS DIRECTLY OVER THE COAST AFTER MIDNIGHT. RATHER SIGNIFICANT
UPPER LEVEL FORCING COULD THUS SUPPORT A FEW ISOLATED SHOWERS
ACROSS NORTHERN BERKELEY AND CHARLESTON COUNTIES BETWEEN MIDNIGHT
AND DAWN SATURDAY MORNING. THERE REMAINS A SMALL POTENTIAL FOR
ISOLATED GRAUPEL OR SOFT HAIL CONSIDERING SUCH COLD AIR ALOFT AND
DECENT LARGE SCALE FORCING. HOWEVER...TEMPERATURES AT THE SURFACE
WILL REMAIN ABOVE FREEZING...WITH LOWS IN THE UPPER 30S TO LOW
40S. WIND SPEEDS APPEAR TO HIGH OVERNIGHT...AND GROUNDS WILL
LIKELY BE TOO WET...TO SUPPORT FROST DEVELOPMENT.
SATURDAY...THE DEEP UPPER LEVEL TROUGH WILL LINGER ALONG THE
EASTERN THIRD OF THE UNITED STATES...WHILE COLD CANADIAN HIGH
PRESSURE SHIFTS TOWARD THE EAST COAST. DESPITE DRY CONDITIONS AND
MOSTLY SUNNY SKIES...TEMPERATURES WILL REMAIN SUPPRESSED IN THE
UPPER 50S TO AROUND 60 DEGREES WITHIN BREEZY WEST/NORTHWEST
WINDS...10 TO 15 DEGREES BELOW SEASONAL NORMALS. ADDITIONAL
SHORTWAVE ENERGY SWEEPING SOUTHEAST FROM THE GREAT LAKES REGION
WILL HELP REINFORCE THE STALLED UPPER TROUGH OVERNIGHT...WITH THE
CENTER OF THE SURFACE HIGH SETTLING DIRECTLY OVER THE REGION. LOW
TEMPERATURES SATURDAY NIGHT WILL REACH THE LOW 30S INLAND TO THE
MID/UPPER 30S CLOSER TO THE COAST. A LIGHT FREEZE REMAINS POSSIBLE
FOR FAR INLAND COUNTIES...WHERE TEMPERATURES COULD REACH 32
DEGREES FOR AN HOUR OR TWO. IT SHOULD BE NOTED THAT IF
NIGHTTIME/EARLY MORNING WIND SPEEDS CAN DIMINISH MORE THAN
CURRENTLY FORECAST...THEN TEMPERATURES COULD BE EVEN COLDER AND
FROST WOULD ALSO BE A CONCERN.
SUNDAY...THE SURFACE HIGH WILL STEADILY DESCEND TOWARD THE
SOUTHEAST COAST...AS THE UPPER TROUGH MOVES INTO THE ATLANTIC.
TEMPERATURES WILL MODERATE JUST A DEGREE OR TWO...AND THUS DESPITE
ANOTHER SUNNY AND DRY DAY...EXPECT HIGHS TO ONLY REACH THE UPPER
50S TO LOW 60S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
THE MID LEVEL PATTERN WILL FLATTEN THROUGH THE EARLY AND MIDDLE
PARTS OF NEXT WEEK...ALTHOUGH A SUBTLE IMPULSE WILL MOVE THROUGH
LATE MONDAY/EARLY TUESDAY. THIS WILL FORCE A COLD FRONT THROUGH THE
FORECAST ZONES...ACCOMPANYING ONLY BY MODEST MOISTURE AND JUST
LIMITED CHANCES FOR SHOWERS. THE FRONT THEN WASHES OUT AND GIVES WAY
TO HIGH PRESSURE THROUGH MID WEEK. WARMER CONDITIONS WILL RETURN AS
EVEN THE AIR MASS BEHIND THE COLD FRONT IS OF PACIFIC ORIGIN SO
TEMPS SHOULD GET BACK NEAR OR EVEN ABOVE SEASONAL NORMS.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
VFR THROUGH THE AFTERNOON INTO THIS EVENING...WITH INCREASING
CHANCES FOR MVFR CIGS AND RAIN SHOWERS AFTER 06Z. THE BULK OF THE
HEAVIEST RAINS WILL LIKELY HOLD OFF UNTIL CLOSER TO SUNRISE
FRIDAY...ALTHOUGH SOME GUIDANCE SUGGESTS EVEN LATER THAN THAT.
WILL INCLUDE PREVAILING 5SM -SHRA FROM 10Z ON AT BOTH TERMINALS.
WILL ALSO INCLUDE A TEMPO FOR BRIEF SHOWERS AT KSAV FROM ROUGHLY
23-01Z AS HIGH RESOLUTION DATA SUPPORT SHOWERS IN THAT AREA ALONG
THE SEA BREEZE.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS LIKELY FRIDAY IN
ASSOCIATION WITH SCATTERED TO NUMEROUS SHRA...AS A COLD FRONT
MOVES THROUGH THE AREA. VFR WEATHER WILL THEN PREVAIL LATE FRIDAY
INTO MONDAY...BEFORE POSSIBLE SUB-VFR WEATHER ACCOMPANIES ANOTHER
COLD FRONT LATE MONDAY.
&&
.MARINE...
SEA FOG...TRICKY SEA FOG FORECAST THROUGH THIS EVENING. LOW-LEVEL
WINDS HAVE TURNED A BIT MORE SOUTHEAST ALONG THE GEORGIA COAST
WHICH IS DIMINISHING PARCEL RESIDENCE TIMES ACROSS THE CORE OF THE
COLDER SHELF WATERS. THIS HAS RESULTED IN AN IMPROVEMENT IN VSBYS
ACROSS BOTH GEORGIA MARINE ZONES. FARTHER NORTH...SOUTHWEST WINDS
HAVE NOT SHOWN ANY INDICATION OF BACKING WITH THE SEA BREEZE...SO
WIDESPREAD DENSE SEA FOG LINGERS. HIGH RESOLUTION MODELS SUGGEST
MOST OF THE FOG ALONG THE LOWER SOUTH CAROLINA COASTAL WATER...OR
AT LEAST A GOOD PORTION OF IT...WILL LIKELY LIFT OR THIN OUT AS
WINDS EVENTUALLY BACK WITH THE STRENGTHENING SEA BREEZE
CIRCULATION. THIS TREND IS SUPPORTED BY BOTH THE RAP AND H3R VSBY
PROGS WHICH HAVE DONE QUITE WELL SO FAR TODAY.
WILL TAKE THE DENSE FOG ADVISORY UNTIL 6 PM FOR THE SOUTH
CAROLINA COASTAL MARINE ZONES...BUT CANCEL IT FOR THE GEORGIA
MARINE ZONES. ATTM IT APPEARS THERE WILL BE ENOUGH MIXING AROUND
CHARLESTON HARBOR FOR THE FOG TO MAKE TOO MUCH PROGRESS INTO THE
MAIN HARBOR ITSELF...BUT WILL MORE LIKELY REMAIN JUST AT THE
HARBOR ENTRANCE AROUND FORT SUMTER. WILL NOT ISSUE A DENSE FOG
ADVISORY FOR THE HARBOR ATTM. THE RISK FOR AT LEAST PATCHY FOG
WILL LINGER THROUGH THE NIGHT AS WINDS EVENTUALLY VEER AHEAD OF
THE COLD FRONT.
TONIGHT...SOUTH WINDS WILL VEER SOUTHWEST AND INCREASE AHEAD OF AN
APPROACHING COLD FRONT. THE COMBINATION OF INCREASING WIND GUSTS
AND SLOWLY BUILDING SEAS WILL SUPPORT SMALL CRAFT ADVISORY
CONDITIONS OVER BOTH THE CHARLESTON COUNTY NEARSHORE WATERS AND
THE GEORGIA OFFSHORE WATERS EARLY FRIDAY MORNING. FLAGS WILL BE
RAISED FOR THESE TWO ZONES WITH THE LATE AFTERNOON FORECAST
PACKAGE. WINDS AND SEAS WILL BE A BIT LESS FOR THE REMAINING
MARINE ZONES WITH SEAS ONLY REACHING 3-5 FT WITH WINDS 15-20 KT.
FRIDAY...THE COMBINATION OF A TIGHT PRESSURE GRADIENT AHEAD AND
ALONG A COLD FRONT...AS WELL AS MIXING IN THE WAKE OF THE
FRONT...WILL SUPPORT GUSTS UP TO 25 KT AND SEAS PEAKING AT 6
FT FOR THE CHARLESTON COUNTY WATERS OFFSHORE GEORGIA MARINE
ZONES. SMALL CRAFT ADVISORIES HAVE THUS BEEN ISSUED FOR THESE
MARINE ZONES. ALTHOUGH WIND FIELDS WILL BE SOMEWHAT ELEVATED AHEAD
OF THE FRONT...SEA FOG WILL PERSIST UNTIL THE FRONT PASSES THROUGH
THE AREA. CONDITIONS WILL FALL BELOW ADVISORY THRESHOLDS FOR THE
CHARLESTON WATERS DURING THE AFTERNOON...YET PERSIST BEYOND 20 NM.
SATURDAY AND SUNDAY...SMALL CRAFT ADVISORY CONDITIONS WILL
CONTINUE FOR THE OUTER GEORGIA WATERS THROUGH THE MORNING
HOURS....ENDING BY EARLY AFTERNOON. STRONG CONTINENTAL HIGH
PRESSURE WILL BUILD FROM THE NORTHWEST AND SUPPORT A SURGE IN
NORTH/NORTHEAST WINDS AROUND DAYBREAK SUNDAY. HOWEVER...EXPECT
WINDS AND SEAS TO REMAIN BELOW ADVISORY CRITERIA. THE HIGH
PRESSURE CENTER WILL THEN SETTLE DIRECTLY OVER THE WATERS BY LATE
IN THE DAY...AND WINDS AND SEAS WILL DIMINISH ACCORDINGLY.
MONDAY AND TUESDAY...HIGH PRESSURE EARLY NEXT WEEK WILL GIVE WAY TO
A COLD FRONT THAT MOVES THROUGH BY EARLY TUESDAY...BEFORE BECOMING
DIFFUSE. MARINE CONDITIONS WILL BE AT OR LESS THAN 15 OR 20 KT FOR
WINDS AND SEAS WILL BE LESS THAN 3 TO 5 FT.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 6 PM EDT THIS EVENING FOR AMZ350-352.
SMALL CRAFT ADVISORY FROM 5 AM FRIDAY TO 1 PM EDT SATURDAY FOR
AMZ374.
SMALL CRAFT ADVISORY FROM 5 AM TO 5 PM EDT FRIDAY FOR AMZ350.
&&
$$
ST/WMS
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1256 PM EDT THU MAR 26 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL WEAKEN AHEAD OF A STRONG COLD FRONT
APPROACHING TONIGHT AND SWEEPING THROUGH DURING FRIDAY. COLDER HIGH
PRESSURE WILL THEN BUILD FOR THE WEEKEND...SUPPORTING A POSSIBLE
FREEZE FOR SOME INLAND AREAS EARLY SUNDAY. HIGH PRESSURE THEN SHIFTS
SOUTH OF THE REGION MONDAY...BEFORE ANOTHER COLD FRONT MOVES
THROUGH LATE MONDAY OR EARLY TUESDAY. HIGH PRESSURE WILL THEN
PREVAIL INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO MAJOR CHANGES WERE MADE WITH THE EARLY AFTERNOON UPDATE.
LOCALLY DENSE SEA FOG WILL AFFECT THE COASTAL COMMUNITIES FROM
EDISTO BEACH NORTHEAST ALONG THE CHARLESTON COUNTY COAST FOR A FEW
HOURS THIS AFTERNOON. IT IS UNCLEAR HOW FAR INLAND THE FOG BANK
WILL PENETRATE AS THE SEA BREEZE DEVELOPS...BUT TRENDS ARE BEING
WATCHED.
THE RISK FOR SHOWER ACTIVITY LOOKS MINIMAL WITH MODIFIED OBSERVED
AND FORECAST SOUNDINGS SHOWING LITTLE IN THE WAY OF INSTABILITY.
THIS IS SUPPORTED BY THE LATEST RAP AND H3R RUNS. THE BEST RAIN
CHANCES WILL HOLD OFF UNTIL AFTER 6 PM AS A COLD FRONT AND
ASSOCIATED SHORTWAVE ENERGY DRAW CLOSER. COULD SEE AN ISOLATED
SHOWER DEVELOP ALONG THE RESULTANT SEA BREEZE ITSELF WHERE LOW-
LEVEL MOISTURE FLUX CONVERGENCE WILL BE LOCALLY MAXIMIZED... BUT
THE OVERALL RISK FOR THIS IS TOO SMALL TO JUSTIFY A MENTIONABLE
POP ATTM. WILL CONTINUE TO MONITOR CONVECTIVE TRENDS THROUGH THE
DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
TONIGHT...RAIN CHANCES INCREASE AS THE FRONT APPROACHES FROM THE
WEST AND LARGE SCALE LIFT/DEEP MOISTURE MOVE INTO THE AREA.
INSTABILITY APPEARS WEAK BUT CANNOT RULE OUT A FEW THUNDERSTORMS
GIVEN THE INCREASING LOW-LEVEL JET/DEEP LAYER SHEAR. GIVEN THE
WARM AND HUMID AIR MASS ADVECTING INTO THE AREA THERE MIGHT STILL
BE SOME SEA FOG NEAR THE COAST...ESPECIALLY UNTIL WINDS BECOME
MORE SOUTHWEST AFTER MIDNIGHT. TEMPS WILL LIKELY NOT DROP BELOW
60 DEGREES.
FRIDAY...A DEEPENING AND AMPLIFYING LONG WAVE TROUGH WILL PREVAIL
OVER THE EASTERN STATES...WITH SOME PHASING OF A SHORT WAVE OVER THE
LOWER MS VALLEY WITH ANOTHER AND STRONGER SHORT WAVE THAT DIVES FROM
THE MID MS VALLEY INTO THE TN VALLEY IN THE AFTERNOON. THIS
TRANSITION WILL CAUSE HEIGHTS ALOFT TO STEADILY FALL AND WILL SHOVE
A STRONG COLD FRONT INTO THE NW TIER DURING THE MID-LATE
MORNING...TOWARD OUR COASTAL CORRIDOR BY EARLY AFTERNOON...AND INTO
THE ATLANTIC THEREAFTER. LOW LEVEL CONVERGENCE WILL COMBINE WITH
LARGER SCALE FORCING FOR ASCENT DUE TO STRONG VERTICAL WIND FIELDS
THROUGHOUT THE TROPOSPHERE...MOST NOTABLY A 30-40 KT LOW LEVEL JET
AND A 130-150 UPPER JET. THESE DYNAMICS WILL HAVE CONSIDERABLE
MOISTURE TO WORK WITH...AS PWATS ARE AS MUCH AS 1-2 STANDARD
DEVIATIONS ABOVE NORMAL FOR LATE MARCH. THIS WILL RESULT IN AT
LEAST 60-70 POPS MAINLY IN THE FORM OF SHOWERS. HOWEVER...GIVEN 50-
60 KT OF BULK SHEAR AND SBCAPES THAT COULD BE AS GREAT AS 300-500
J/KG THERE CERTAINLY COULD BE A FEW RUMBLES OF THUNDER. RAIN CHANCES
WILL PEAK IN THE MORNING...THEN TAIL OFF FROM WEST TO EAST IN THE
AFTERNOON.
WARM ADVECTION IN ADVANCE OF THE COLD FRONT WILL ASSIST IN NEGATING
THE LACK OF INSOLATION...BUT FRIDAY WILL CERTAINLY BE NOTICEABLY
COOLER THAN IT WILL BE TODAY. IN FACT AS COLD ADVECTION ARRIVES IN
THE AFTERNOON THERE COULD ACTUALLY BE SOME SLOW FALL TO SOME OF OUR
TEMPS THE REST OF THE DAY.
FRIDAY NIGHT...ALTHOUGH THE DEEP MOISTURE WILL HAVE PULLED EAST WITH
THE COLD FRONT...THERE IS STILL SOME LINGERING LOW LEVEL MOISTURE
WITHIN THE FIRST COUPLE OF MILES OFF THE DECK. A POTENT SHORT WAVE
EMBEDDED WITHIN THE LONG WAVE TROUGH ALOFT WILL MOVE DIRECTLY
THROUGH THE CWFA AROUND 05-08Z. THIS WILL SUPPORT 20-30 POPS AND
MAINLY ACROSS THE CHARLESTON TRI-COUNTY REGION WHERE THE BEST
MOISTURE WILL REMAIN. ALTHOUGH COLDER AIR WILL BE FILTERING IN...AS
PER SOUNDING PROFILES IT LOOKS LIKE ONE OF THOSE EVENTS WHERE THE
COLD AIR IS TRYING TO CATCH UP TO THE DEPARTING MOISTURE AND IT WILL
ARRIVE TOO LATE TO PRODUCE ANYTHING OTHER THAN LIQUID. BUT DUE TO
THE STEEP MID LEVEL LAPSE RATES WHERE 500 MB TEMPS ARE NEAR MINUS
27C...THERE APPEARS TO BE A RISK FOR SOME GRAUPEL OR SOFT HAIL. 850
MB TEMPS WILL PLUNGE TO -3C SOUTH AND -6C NORTH...SUPPORTIVE OF
LOWEST TEMPS IN THE MID 30S TO LOWER 40S. BUT THERE IS TOO MUCH WIND
AND THE GROUNDS ARE TOO WET FOR ANY FROST.
SATURDAY...THE LARGE SCALE EAST COAST TROUGH REMAINS IN
PLACE...WHILE SIMULTANEOUSLY SURFACE HIGH PRESSURE GRADUALLY BUILDS
FROM THE WEST/NW. ANOTHER SHORT WAVE EMBEDDED WITHIN THE DEEP NW
FLOW WILL DROP THROUGH THE UPPER MIDWEST TO NEAR THE SOUTHERN
APPALACHIANS LATE. THIS WILL RESULT IN AN INCREASE IN MID/HIGH LEVEL
CLOUDS OVER THE SW PART OF THE CWFA. ALTHOUGH THERE IS DECENT
INSOLATION...WITH 850 MB TEMPS CLOSE TO 2 STANDARD DEVIATIONS BELOW
NORMAL WE/LL BE HARD PRESSED TO REACH AN MORE THAN 55-60F.
SATURDAY NIGHT...THE AFOREMENTIONED SHORT WAVE WILL PULL THROUGH
OVERNIGHT AND USHER IN A 1033 ARCTIC HIGH FROM THE OHIO VALLEY. THE
ASSOCIATED COLD ADVECTION WILL RESULT IN UNSEASONABLY COLD AIR
PENETRATING INTO THE BULK OF THE FORECAST DISTRICT. THERE LOOKS TO
BE TOO MUCH MIXING TO PREVENT A HARD FREEZE...BUT A LIGHT FREEZE IS
CERTAINLY POSSIBLE ACROSS AT LEAST THE NW TIER. IF WINDS DO DROP OFF
ENOUGH THEN TEMPS COULD BE EVEN COLDER THAN 30-32F IN THESE SECTIONS
AND FROST WOULD ALSO BE A CONCERN IN MANY OTHER COMMUNITIES SOUTH
AND EAST.
SUNDAY...THE EAST COAST TROUGH LIFTS OUT AND GIVES WAY TO SHORT WAVE
RIDGING AND ITS ASSOCIATED RISING HEIGHTS...AS THE CORE OF THE
ARCTIC HIGH SHIFTS DIRECTLY OVERHEAD. DESPITE PLENTIFUL SUNSHINE AND
THE AIR MASS MODIFYING...TEMPS WILL ONLY BE ABLE TO MUSTER THE UPPER
50S AND LOWER 60S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
THE MID LEVEL PATTERN WILL FLATTEN THROUGH THE EARLY AND MIDDLE
PARTS OF NEXT WEEK...ALTHOUGH A SUBTLE IMPULSE WILL MOVE THROUGH
LATE MONDAY/EARLY TUESDAY. THIS WILL FORCE A COLD FRONT THROUGH THE
FORECAST ZONES...ACCOMPANYING ONLY BY MODEST MOISTURE AND JUST
LIMITED CHANCES FOR SHOWERS. THE FRONT THEN WASHES OUT AND GIVES WAY
TO HIGH PRESSURE THROUGH MID WEEK. WARMER CONDITIONS WILL RETURN AS
EVEN THE AIR MASS BEHIND THE COLD FRONT IS OF PACIFIC ORIGIN SO
TEMPS SHOULD GET BACK NEAR OR EVEN ABOVE SEASONAL NORMS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
VFR THROUGH THE AFTERNOON INTO THIS EVENING...WITH INCREASING
CHANCES FOR MVFR CIGS AND RAIN SHOWERS AFTER 06Z. THE BULK OF THE
HEAVIEST RAINS WILL LIKELY HOLD OFF UNTIL CLOSER TO SUNRISE
FRIDAY...ALTHOUGH SOME GUIDANCE SUGGESTS EVEN LATER THAN THAT.
WILL INCLUDE PREVAILING 5SM -SHRA FROM 10Z ON AT BOTH TERMINALS.
WILL ALSO INCLUDE A TEMPO FOR BRIEF SHOWERS AT KSAV FROM ROUGHLY
23-01Z AS HIGH RESOLUTION DATA SUPPORT SHOWERS IN THAT AREA ALONG
THE SEA BREEZE.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS LIKELY FRIDAY IN
ASSOCIATION WITH SCATTERED TO NUMEROUS SHRA AND POSSIBLE TSRA AS A
COLD FRONT MOVES THROUGH. VFR WEATHER WILL THEN PREVAIL LATE FRIDAY
INTO MONDAY...WITH POSSIBLE SUB-VFR WEATHER WITH ANOTHER COLD FRONT
LATE MONDAY.
&&
.MARINE...
EXPANDED THE MARINE DENSE FOG ADV NORTHEAST TO THE CHARLESTON
COUNTY WATERS AND THE GEORGIA OFFSHORE WATER PER SATELLITE TRENDS
AND WEBCAM OBSERVATIONS.
TODAY...WEBCAMS OFF HILTON HEAD AND EDISTO BEACH SUGGEST THE SEA
FOG HAS LIFTED SOME OVER THE PAST 1-2 HOURS. HOWEVER...WINDS ARE
FORECAST TO RETURN TO A MOVE SOUTHERLY DIRECTION AS THE MORNING
LAND BREEZE DISSIPATES AND A SEA BREEZE INITIATES. THIS WILL
RETURN THE LOW- LEVEL FLOW TO A MORE FAVORABLE GEOMETRY FOR SEA
FOG DEVELOPMENT. WILL MAINTAIN THE MARINE DENSE FOG ADVISORY FOR
THE NEARSHORE WATERS FROM EDISTO BEACH SOUTH. THE FOG COULD EXPAND
INTO THE CHARLESTON COUNTY WATERS LATER THIS AFTERNOON...SO THE
ADVISORY MAY NEED TO BE EXPANDED WITH LATER FORECAST CYCLES.
TONIGHT...VEERING WINDS AHEAD OF AN APPROACHING COLD FRONT LATE
TONIGHT. WARM AND MOIST AIR MASS WILL REMAIN IN PLACE CREATING A
GOOD ENVIRONMENT FOR SEA FOG. WINDS/SEAS WILL APPROACH SMALL CRAFT
ADVISORY LEVELS LATE TONIGHT BEYOND 20 NM.
FRIDAY...A FAIRLY TIGHT AND CYCLONIC SW PRESSURE PATTERN WILL
PREVAIL IN ADVANCE OF THE COLD FRONT THAT DOESN/T MOVE THROUGH AFTER
1 OR 2 PM. WARM ADVECTION WILL RESTRICT THE AMOUNT OF MIXING...BUT
GIVEN GEOSTROPHIC WINDS OF 30 KT OR SO THIS WILL SUPPORT MARGINAL
SMALL CRAFT ADVISORIES ACROSS THE AMZ374 WATERS FOR GUSTS UP NEAR 25
KT AND SEAS AS HIGH AS 6 FT. WE STILL MIGHT NEED TO EXPAND THE
ADVISORY TO ENCOMPASS AMZ350...BUT FOR NOW THOSE WATERS LOOK TO
REMAIN JUST BELOW ANY ADVISORY CONDITIONS. EVEN THOUGH WIND FIELDS
WILL BE SOMEWHAT ELEVATED...SEA FOG WILL CONTINUE UNTIL THE FRONT
SCOURS THINGS OUT AND VISIBILITIES IMPROVE. MARINERS SHOULD ALSO
REMAIN ALERT FOR POSSIBLE T-STORMS...MOST ESPECIALLY ACROSS THE GULF
STREAM WATERS.
FRIDAY NIGHT AND SATURDAY...A MIXTURE OF COLD ADVECTION AND GOOD
ISALLOBARIC PRESSURE RISES WILL LIKELY SUPPORT ADDITIONAL SMALL
CRAFT ADVISORIES AS NW WINDS APPROACH 20-25 KT IN WAKE OF THE COLD
FRONT AND STRENGTHENING ATLANTIC LOW PRESSURE SOUTH/SE OF NEW ENGLAND.
SATURDAY NIGHT AND SUNDAY...STRONG CONTINENTAL HIGH PRESSURE WILL
BUILD FROM THE NW AND WILL BE ACCOMPANIED BY A SURGE OF NORTH/NE
WINDS AROUND DAYBREAK SUNDAY...BUT LIKELY BENEATH ANY ADVISORY
CRITERIA. THE HIGH WILL THEN SETTLE ATOP THE WATERS BY LATE IN THE
DAY AND WINDS AND SEAS WILL COME DOWN.
MONDAY AND TUESDAY...HIGH PRESSURE EARLY NEXT WEEK WILL GIVE WAY TO
A COLD FRONT THAT MOVES THROUGH BY EARLY TUESDAY...BEFORE BECOMING
DIFFUSE. MARINE CONDITIONS WILL BE AT OR LESS THAN 15 OR 20 KT FOR
WINDS AND LESS THAN 3-5 FOOT SEAS.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...DENSE FOG ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ352-354.
DENSE FOG ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR AMZ350-
374.
SMALL CRAFT ADVISORY FROM 6 AM FRIDAY TO 1 PM EDT SATURDAY FOR
AMZ374.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS JACKSON KY
305 PM EDT THU MAR 26 2015
.UPDATE...
ISSUED AT 938 AM EDT THU MAR 26 2015
THE LINE OF SHOWERS AND THUNDERSTORMS THAT MOVED INTO CENTRAL AND
EASTERN KY THIS MORNING HAS BEEN IN A DETERIORATING STATE FOR THE
LAST COUPLE OF HOURS. AT THIS RATE...MOST OF EASTERN KY WILL
LIKELY SEE SOME SCATTERED LIGHT SHOWERS...BUT NOTHING STRONG
ENOUGH TO PRODUCE THUNDER. FURTHERMORE...DOWNSTREAM...AS
STRATIFORM RAIN BEGINS TO FILL IN ALONG AND BEHIND THE FRONTAL
BOUNDARY...WINDS HAVE ALREADY BEGAN SHIFTING TO THE NE. THIS WILL
CREATE A QUICK SURFACE INVERSION AS COLDER AIR FILTERS IN...AND
WILL ELIMINATE THE THREAT OF THUNDER DEVELOPMENT HERE AS WELL. AS
SUCH...EXPANDED CHANCE AND LIKELY POPS ACROSS OUR CWA AS THIS LINE
BREAKS APART AND SCATTERS OUT OVER THE NEXT COUPLE OF HOURS. ALSO
WENT AHEAD AND REMOVED ANY MENTION OF THUNDER FROM THE FORECAST
FOR THE DURATION OF THE DAY. DID KEEP WITH PREVIOUS FORECAST
MENTION OF CONVECTIVE SHOWERS AHEAD OF THE FRONT...AND MORE
STRATIFORM RAIN BEHIND THE FRONTAL ZONE.
UPDATE ISSUED AT 821 AM EDT THU MAR 26 2015
A LINE OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS HAVE MOVED IN
FROM CENTRAL KENTUCKY THIS MORNING. HAVE FRESHENED UP THE FORECAST
TO ACCOUNT FOR THIS BAND...WHICH WILL GRADUALLY WEAKEN AS IT COMES
EAST. ONCE THIS BAND MOVES THROUGH...STILL EXPECTING ADDITIONAL
ACTIVITY TO INITIATE UPSTREAM AND MOVE IN THIS AFTERNOON...SO
JUST BLENDED INTO THE EXISTING FORECAST AFTER THE MID-MORNING
HOURS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 357 AM EDT THU MAR 26 2015
A SURFACE COLD FRONT IS CURRENTLY ALIGNED FROM NORTHEAST OHIO
DOWN THROUGH NORTH CENTRAL AND SOUTHWESTERN KENTUCKY. CONVECTION
HAS BEEN ONGOING OFF TO OUR WEST...AND HAS BEEN SHOWING A GENERAL
WEAKENING TREND ACCORDING TO THE LIGHTNING DATA AND WARMING CLOUD
TOPS EVIDENT ON THE IR SATELLITE. THERE HAS BEEN SOME NEW
DEVELOPMENT OUT AHEAD OF THE MAIN CLUSTERS...WITH SOME SCATTERED
STORMS POPPING UP JUST EAST OF I-75 IN NORTH CENTRAL KENTUCKY.
EASTERN KENTUCKY REMAINS IN THE WARM SECTOR...ALTHOUGH A FEW
SHELTERED VALLEYS IN OUR FAR EAST HAVE MANAGED TO DROP OFF INTO
THE 40S.
THE MODELS HAVE REMAINED IN PRETTY GOOD AGREEMENT WITH THE
DEVELOPING DEEP LONG WAVE TROUGH TO MOVE EAST ACROSS THE
MISSISSIPPI VALLEY. INITIALLY...HAVE FOLLOWED THE HRRR THROUGH
THIS MORNING...AND THEN A BLEND OF THE MODELS THEREAFTER.
CONVECTION WILL DRAW CLOSER TO THE AREA THROUGH DAWN...WITH AT
LEAST SOME SCATTERED ACTIVITY TO CONTEND WITH THROUGH THE MORNING
HOURS...PARTICULARLY IN THE WESTERN HALF OF THE CWA. THE MAIN
BATCH OF CONVECTION SHOULD STAY TO THE NORTHWEST. A STRENGTHENING
UPPER LEVEL JET ACROSS THE OHIO VALLEY WILL HELP RECHARGE THE
FRONT THIS AFTERNOON...SO WIDESPREAD PRECIPITATION WILL EVENTUALLY
MOVE IN ACROSS ALL OF EASTERN KENTUCKY THROUGH EARLY THIS EVENING.
SHOWERS AND SCATTERED THUNDERSTORMS WILL GIVE WAY TO MAINLY RAIN
BEHIND THE DEPARTING COLD FRONT...WITH THE SOUTHEAST LIKELY SEEING
THE HIGHER AMOUNTS OF QPF...WHERE A HALF INCH OR MORE COULD FALL.
DRY SLOTTING WILL WORK IN TONIGHT BEHIND AN INITIAL DEPARTING
SHORT WAVE TROUGH...WITH MOISTURE LIKELY CUTTING OFF BEFORE
TEMPERATURES GET COLD ENOUGH TO SUPPORT A FEW FLAKES. ON
FRIDAY...THE MAIN TROUGH AXIS WILL MOVE THROUGH THE AREA DURING
THE AFTERNOON HOURS...ALLOWING FOR SOME ISOLATED TO SCATTERED
SHOWERS.
HIGHS TODAY WILL LIKELY BE ESTABLISHED IN THE MORNING FOR MOST
LOCATIONS. READINGS WILL RANGE FROM AROUND 60 IN THE FAR
NORTHWEST...TO THE LOW TO MID 70S IN FAR EAST AND SOUTHEAST.
TEMPERATURES WILL FALL OFF TO THE 40S AND 50S BY LATE IN THE
DAY...WITH LOWS TONIGHT BOTTOMING OUT IN THE LOW TO MID 30S. HIGHS
ON FRIDAY WILL ONLY RECOVER TO THE 40S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 305 PM EDT THU MAR 26 2015
THERE IS GOOD MODEL AGREEMENT ON THE OVERALL EVOLUTION OF THE MEAN
PATTERN AS WE MOVE FROM A HIGHLY AMPLIFIED PATTERN WITH A DEEP
TROUGH IN THE EASTERN UNITED STATES AT THE BEGINNING OF THE
FORECAST PERIOD TO ZONAL FLOW NEXT WEEK. THIS WILL SPELL A
MODERATING TREND AFTER THE WEEKEND...BUT WITH FAST ZONAL FLOW WE
WILL SEE A SERIES OF WEAK FRONTAL SYSTEMS AFFECT THE AREA NEXT
WEEK...WITH EACH ONE BRINGING A CHANCE FOR RAIN. IN FACT THE
CHANCE OF RAIN WILL RETURN SUNDAY NIGHT. TEMPERATURES AT THE START
OF NEXT WEEK WILL RETURN TO NEAR NORMAL READINGS AND WILL THEN
TREND TO ABOVE NORMAL READINGS DURING THE SECOND HALF OF THE WEEK.
HOWEVER...BEFORE THE MODERATING TREND OF NEXT WEEK WE WILL NEED TO
ENDURE UNSEASONABLY COLD WEATHER FOR THE FIRST PART OF THE WEEKEND.
TEMPERATURES FROM SATURDAY INTO SUNDAY MORNING WILL AVERAGE ABOUT 20
DEGREES BELOW NORMAL. SURFACE HIGH PRESSURE WILL SETTLE INTO EASTERN
KY SATURDAY NIGHT. CLEARING SKIES AND LIGHT WINDS WILL ALLOW FOR
GOOD RADIATIONAL COOLING...WITH LOWS DIPPING DOWN INTO THE LOWER TO
MIDDLE 20S BY SUNDAY MORNING. AS HIGH PRESSURE SHIFTS EAST ON SUNDAY
AND WINDS BECOME SOUTHERLY TEMPERATURES WILL REBOUND INTO THE LOWER
TO MIDDLE 50S SUNDAY AFTERNOON.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 152 PM EDT THU MAR 26 2015
A COLD FRONT IS CURRENTLY TRAVERSING FAR EASTERN KY...BRINGING
WITH IT A LINE OF HEAVY RAIN SHOWERS AND GUSTY WINDS. THESE
SHOWERS HAVE ALREADY PASSED THROUGH KSYM...KSME AND KLOZ WITH
IMPROVING CONDITIONS...BUT WILL CONTINUE TO AFFECT KJKL AND KSJS
OVER THE NEXT 30 TO 45 MINUTES. BEHIND THIS FRONTAL LINE...WINDS
ARE MAKING A QUICK SHIFT TO THE NW...ALLOWING MUCH COLDER AIR TO
WORK IN. EXPECT GUSTS OF 15 TO 20KTS TO CONTINUE OVER THE NEXT FEW
HOURS...BEFORE FINALLY DIMINISHING THIS EVENING AND OVERNIGHT AS
WINDS BECOME MORE NRLY. STRATIFORM RAIN IS CURRENTLY LOCATED OVER
WESTERN AND CENTRAL KY...AND SHOULD CONTINUE TO SLOWLY SHIFT INTO
OUR AREA THIS AFTERNOON...IMPACTING MOST OF THE TAF SITES WELL
INTO THE OVERNIGHT. EXPECT CIGS TO SLOWLY DETERIORATE INTO THE
MVFR TO IFR RANGE BY THIS EVENING...BETWEEN 500 AND 1000FT. BY
TOMORROW MORNING...RAIN WILL CLEAR OUT AND CIGS WILL LIKELY
IMPROVE...THOUGH MODELS ARE CONTINUING TO SUPPORT THE RETURN OF A
LAYER OF HIGH MVFR OR LOW END VFR CLOUDS BY THE END OF THE TAF
PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GEOGERIAN
LONG TERM...SBH
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
152 PM EDT THU MAR 26 2015
.UPDATE...
ISSUED AT 938 AM EDT THU MAR 26 2015
THE LINE OF SHOWERS AND THUNDERSTORMS THAT MOVED INTO CENTRAL AND
EASTERN KY THIS MORNING HAS BEEN IN A DETERIORATING STATE FOR THE
LAST COUPLE OF HOURS. AT THIS RATE...MOST OF EASTERN KY WILL
LIKELY SEE SOME SCATTERED LIGHT SHOWERS...BUT NOTHING STRONG
ENOUGH TO PRODUCE THUNDER. FURTHERMORE...DOWNSTREAM...AS
STRATIFORM RAIN BEGINS TO FILL IN ALONG AND BEHIND THE FRONTAL
BOUNDARY...WINDS HAVE ALREADY BEGAN SHIFTING TO THE NE. THIS WILL
CREATE A QUICK SURFACE INVERSION AS COLDER AIR FILTERS IN...AND
WILL ELIMINATE THE THREAT OF THUNDER DEVELOPMENT HERE AS WELL. AS
SUCH...EXPANDED CHANCE AND LIKELY POPS ACROSS OUR CWA AS THIS LINE
BREAKS APART AND SCATTERS OUT OVER THE NEXT COUPLE OF HOURS. ALSO
WENT AHEAD AND REMOVED ANY MENTION OF THUNDER FROM THE FORECAST
FOR THE DURATION OF THE DAY. DID KEEP WITH PREVIOUS FORECAST
MENTION OF CONVECTIVE SHOWERS AHEAD OF THE FRONT...AND MORE
STRATIFORM RAIN BEHIND THE FRONTAL ZONE.
UPDATE ISSUED AT 821 AM EDT THU MAR 26 2015
A LINE OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS HAVE MOVED IN
FROM CENTRAL KENTUCKY THIS MORNING. HAVE FRESHENED UP THE FORECAST
TO ACCOUNT FOR THIS BAND...WHICH WILL GRADUALLY WEAKEN AS IT COMES
EAST. ONCE THIS BAND MOVES THROUGH...STILL EXPECTING ADDITIONAL
ACTIVITY TO INITIATE UPSTREAM AND MOVE IN THIS AFTERNOON...SO
JUST BLENDED INTO THE EXISTING FORECAST AFTER THE MID-MORNING
HOURS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 357 AM EDT THU MAR 26 2015
A SURFACE COLD FRONT IS CURRENTLY ALIGNED FROM NORTHEAST OHIO
DOWN THROUGH NORTH CENTRAL AND SOUTHWESTERN KENTUCKY. CONVECTION
HAS BEEN ONGOING OFF TO OUR WEST...AND HAS BEEN SHOWING A GENERAL
WEAKENING TREND ACCORDING TO THE LIGHTNING DATA AND WARMING CLOUD
TOPS EVIDENT ON THE IR SATELLITE. THERE HAS BEEN SOME NEW
DEVELOPMENT OUT AHEAD OF THE MAIN CLUSTERS...WITH SOME SCATTERED
STORMS POPPING UP JUST EAST OF I-75 IN NORTH CENTRAL KENTUCKY.
EASTERN KENTUCKY REMAINS IN THE WARM SECTOR...ALTHOUGH A FEW
SHELTERED VALLEYS IN OUR FAR EAST HAVE MANAGED TO DROP OFF INTO
THE 40S.
THE MODELS HAVE REMAINED IN PRETTY GOOD AGREEMENT WITH THE
DEVELOPING DEEP LONG WAVE TROUGH TO MOVE EAST ACROSS THE
MISSISSIPPI VALLEY. INITIALLY...HAVE FOLLOWED THE HRRR THROUGH
THIS MORNING...AND THEN A BLEND OF THE MODELS THEREAFTER.
CONVECTION WILL DRAW CLOSER TO THE AREA THROUGH DAWN...WITH AT
LEAST SOME SCATTERED ACTIVITY TO CONTEND WITH THROUGH THE MORNING
HOURS...PARTICULARLY IN THE WESTERN HALF OF THE CWA. THE MAIN
BATCH OF CONVECTION SHOULD STAY TO THE NORTHWEST. A STRENGTHENING
UPPER LEVEL JET ACROSS THE OHIO VALLEY WILL HELP RECHARGE THE
FRONT THIS AFTERNOON...SO WIDESPREAD PRECIPITATION WILL EVENTUALLY
MOVE IN ACROSS ALL OF EASTERN KENTUCKY THROUGH EARLY THIS EVENING.
SHOWERS AND SCATTERED THUNDERSTORMS WILL GIVE WAY TO MAINLY RAIN
BEHIND THE DEPARTING COLD FRONT...WITH THE SOUTHEAST LIKELY SEEING
THE HIGHER AMOUNTS OF QPF...WHERE A HALF INCH OR MORE COULD FALL.
DRY SLOTTING WILL WORK IN TONIGHT BEHIND AN INITIAL DEPARTING
SHORT WAVE TROUGH...WITH MOISTURE LIKELY CUTTING OFF BEFORE
TEMPERATURES GET COLD ENOUGH TO SUPPORT A FEW FLAKES. ON
FRIDAY...THE MAIN TROUGH AXIS WILL MOVE THROUGH THE AREA DURING
THE AFTERNOON HOURS...ALLOWING FOR SOME ISOLATED TO SCATTERED
SHOWERS.
HIGHS TODAY WILL LIKELY BE ESTABLISHED IN THE MORNING FOR MOST
LOCATIONS. READINGS WILL RANGE FROM AROUND 60 IN THE FAR
NORTHWEST...TO THE LOW TO MID 70S IN FAR EAST AND SOUTHEAST.
TEMPERATURES WILL FALL OFF TO THE 40S AND 50S BY LATE IN THE
DAY...WITH LOWS TONIGHT BOTTOMING OUT IN THE LOW TO MID 30S. HIGHS
ON FRIDAY WILL ONLY RECOVER TO THE 40S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 357 PM EDT WED MAR 25 2015
GUIDANCE IS IN GOOD AGREEMENT WITH THE BASE OF THE AMPLIFIED
TROUGH AXIS MOVING ACROSS THE OHIO VALLEY TO BEGIN THE PERIOD.
UNDER NORTHWEST FLOW AND COLDER AIR ALOFT MOVING ACROSS BASED ON
FORECAST SOUNDINGS...IT SEEMS REASONABLE TO MAINTAIN SMALL CHANCES
OF RAIN SHOWERS FRIDAY EVENING. AS WE COOL OFF...WOULD EXPECT A
CHANGE OVER TO A MIX/SNOW SHOWERS FRIDAY NIGHT PARTICULARLY
ACROSS THE FAR SE. BASED ON FORECAST SOUNDINGS WE REALLY DRY OUT
IN THE UPPER LEVELS BY SATURDAY MORNING...BUT SOUNDINGS TRY TO AT
LEAST HOLD ON TO SOME HIGH LEVEL CLOUDS. GIVEN THE COLD AIR MASS
IN PLACE WITH H850 SUB MINUS 10 IT WILL BE A COLD NIGHT WITH LOWS
IN THE LOW TO MID 20S. THIS UPPER LEVEL TROUGH CONTINUES TO SLIDE
EAST SATURDAY WITH THE COLD AIR MASS KEEPING HIGHS IN THE UPPER
30 TO LOWER 40S MOST SPOTS.
THE CANADIAN HIGH WILL CONTINUE TO BUILD SOUTHEAST SATURDAY INTO
SATURDAY NIGHT. THIS WILL BE THE BEST NIGHT FOR CLEAR SKIES AND
FROST. RIGHT NOW IT ALL DEPENDS ON HOW THE HIGH ALIGNS ACROSS THE
REGION TO WHERE THE MAX POTENTIAL FOR COOLING WILL BE. THE HIGH
SLIDES EAST FOR SUNDAY USHERING IN RETURN FLOW AND WARMER TEMPS.
WHILE UNCERTAINTY REMAINS ON THE EXACT EVOLUTION OF THE SYSTEM
MOVING INTO THE BEGINNING OF NEXT WEEK WITH A MORE PROGRESSIVE
GFS VERSUS OTHER GUIDANCE...EITHER WAY IT DOES LOOK LIKE CHANCES
OF RAIN SHOWERS INCREASE SUNDAY NIGHT INTO MONDAY. THERE IS ANOTHER
POTENTIAL SYSTEM BY MID WEEK WITH MODEL UNCERTAINTY REMAINING
HERE. THE GFS IS AGAIN QUICKER...WITH MORE OF A SOUTHERN STREAM
INFLUENCE VERSUS THE ECMWF NORTHERN STREAM FRONT BEING THE BIGGER
INFLUENCE. GIVEN THE UNCERTAINTY IN THESE SYSTEMS...DID STICK
CLOSE TO A MODEL BLEND...WHICH KEEPS SLIGHT TO CHANCE POPS WITH
BOTH SYSTEMS. OTHERWISE THE BEST BREAK IN THE ACTIVE PATTERN
LOOKS TO BE ON TUESDAY IN BETWEEN THESE SYSTEMS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 152 PM EDT THU MAR 26 2015
A COLD FRONT IS CURRENTLY TRAVERSING FAR EASTERN KY...BRINGING
WITH IT A LINE OF HEAVY RAIN SHOWERS AND GUSTY WINDS. THESE
SHOWERS HAVE ALREADY PASSED THROUGH KSYM...KSME AND KLOZ WITH
IMPROVING CONDITIONS...BUT WILL CONTINUE TO AFFECT KJKL AND KSJS
OVER THE NEXT 30 TO 45 MINUTES. BEHIND THIS FRONTAL LINE...WINDS
ARE MAKING A QUICK SHIFT TO THE NW...ALLOWING MUCH COLDER AIR TO
WORK IN. EXPECT GUSTS OF 15 TO 20KTS TO CONTINUE OVER THE NEXT FEW
HOURS...BEFORE FINALLY DIMINISHING THIS EVENING AND OVERNIGHT AS
WINDS BECOME MORE NRLY. STRATIFORM RAIN IS CURRENTLY LOCATED OVER
WESTERN AND CENTRAL KY...AND SHOULD CONTINUE TO SLOWLY SHIFT INTO
OUR AREA THIS AFTERNOON...IMPACTING MOST OF THE TAF SITES WELL
INTO THE OVERNIGHT. EXPECT CIGS TO SLOWLY DETERIORATE INTO THE
MVFR TO IFR RANGE BY THIS EVENING...BETWEEN 500 AND 1000FT. BY
TOMORROW MORNING...RAIN WILL CLEAR OUT AND CIGS WILL LIKELY
IMPROVE...THOUGH MODELS ARE CONTINUING TO SUPPORT THE RETURN OF A
LAYER OF HIGH MVFR OR LOW END VFR CLOUDS BY THE END OF THE TAF
PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GEOGERIAN
LONG TERM...DJ
AVIATION...JMW
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1239 PM CDT THU MAR 26 2015
.UPDATE...
ISSUED AT 1239 PM CDT THU MAR 26 2015
UPDATED FOR THE NEW 18Z AVIATION DISCUSSION BELOW.
UPDATE ISSUED AT 942 AM CDT THU MAR 26 2015
EXTENDED THE LAKE SNOW ADVISORY FOR IRON COUNTY UNTIL 05Z FRI AFTER
COORDINATION WITH MQT AND THE RAP SOUNDINGS INDICATING THE WINDS
STAY FAVORABLE FOR SNOW SHOWERS THROUGH THIS EVENING. A SHORTWAVE
WILL MOVE THROUGH THE REGION TONIGHT WHICH SHOULD SWITCH THE
WINDS. CURRENT WEBCAMS AND REPORTS INDICATE SNOW SHOWERS IS STILL
COMING DOWN.
ALSO...MADE ADJUSTMENTS TO CLOUD COVER AND TEMPS BASED ON CURRENT
TRENDS ON SATELLITE AND CURRENT OBS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 309 AM CDT THU MAR 26 2015
A MUCH COOLER AND DRIER AIR MASS DESCENDS INTO THE UPPER MIDWEST
TODAY. PRIMARY FORECAST CONCERN IS LAKE EFFECT SNOW SHOWERS ALONG
THE SOUTH SHORE OF LAKE SUPERIOR. OTHERWISE COOL AND DRY AS HIGH
PRESSURE MOVES ACROSS NORTHERN MINNESOTA TONIGHT INTO TOMORROW.
SOUTH SHORE OF LAKE SUPERIOR...THE LAKE EFFECT SNOW SHOWERS ARE
BEGINNING TO INTENSIFY AS OF 08Z/3AM CDT AND WILL PERSIST THROUGH
THIS MORNING. WITH A VERY DRY AIR MASS MOVING IN FROM THE NORTH THE
WINDOW FOR THE BEST LAKE EFFECT ENVIRONMENT WILL BE CLOSING THIS
AFTERNOON...AND GIVEN THE LATEST SUITE OF GUIDANCE HAVE DECIDED TO
DECREASE SNOW TOTALS BY A BIT. WILL LIKELY LET THE CURRENT ADVISORY
FOR IRON COUNTY RUN THROUGH THE EARLY MORNING HOURS...SINCE REVISED
LOWER SNOWFALL AMOUNTS OF TWO TO FOUR INCHES IS STILL WITHIN THE
ADVISORY CRITERIA. SNOWFALL TAPERS OFF THIS AFTERNOON BUT COULD SEE
ANOTHER PULSE OF SNOW SHOWERS THIS EVENING AS LOW LEVEL WINDS VEER
FROM THE NORTH TO NORTHEAST RESULTING IN A LONGER FETCH...BUT
SNOWFALL AMOUNTS THIS EVENING WOULD LIKELY ONLY BE AN INCH OR TWO.
ADDED SOME GENEROUS FLURRIES INTO PARTS OF NORTHWEST WISCONSIN BASED
OFF SOME OF THE MORE AGGRESSIVE CONVECTION-ALLOWING GUIDANCE...BUT
GENERALLY ACCUMULATING SNOWFALL WILL BE LIMITED TO HIGHER TERRAIN
ALONG THE SOUTH SHORE.
ELSEWHERE TODAY...DECREASING CLOUDS IN THE MORNING BECOMING SUNNY
THIS AFTERNOON. BREEZY NORTH/NORTHWEST WINDS EARLY THIS MORNING
BECOMING LIGHT OUT OF THE NORTH AT 5 TO 15 MPH LATE IN THE MORNING
INTO THE AFTERNOON. COOLER...HIGH TEMPERATURES IN THE MID 20S TO MID 30S.
TONIGHT...CLEAR SKIES AND COLD. NEAR CALM WINDS AS THE HIGH PRESSURE
BECOMES CENTERED OVER NORTHERN MINNESOTA. TEMPERATURES IN THE SINGLE
DIGITS TO LOW TEENS...WITH LOWS NEAR ZERO IN THE TIP OF THE
ARROWHEAD.
FRIDAY...SUNNY AND DRY. A FEW HIGH CLOUDS LATE IN THE DAY BUT
OTHERWISE SUNNY. WINDS BECOMING SOUTHERLY AND LIGHT AT LESS THAN 10
MPH. RELATIVE HUMIDITY VALUES COULD DROP TO 25 TO 35 PERCENT IN THE
AFTERNOON...BUT THERE ARE NO FIRE WEATHER CONCERNS DUE TO WEAK
WINDS. TEMPERATURES COOL...HIGHS IN THE LOW TO MID 30S...EXCEPT
ALONG THE TIP OF THE ARROWHEAD WHERE TEMPERATURES WILL BE LIMITED TO
THE MID 20S.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 309 AM CDT THU MAR 26 2015
THE UPPER FLOW WILL BE NORTHWEST THROUGH MUCH OF THE PERIOD A
WESTERN RIDGE PERSISTING. THE FLOW IS FORECAST TO BECOME MORE ZONAL
LATE IN THE PERIOD. SEVERAL SHORTWAVES WILL MOVE THROUGH THE REGION
DURING THE PERIOD BRINGING A CHANCE FOR PRECIPITATION TO THE
NORTHLAND.
A DEPARTING SURFACE HIGH AND UPPER RIDGE WILL CAUSE DRY CONDITIONS
FRIDAY NIGHT INTO SATURDAY. WE LOWERED TEMPS FRIDAY NIGHT AS LIGHT
WINDS AND CLEAR SKIES ARE EXPECTED. SATURDAY WILL FEATURE THICKENING
CLOUDS AS MID LEVEL WAA DEVELOPS.
AN AREA OF LOW PRESSURE AND STRONG SHORTWAVE WILL START TO IMPACT
THE NORTHLAND SATURDAY NIGHT AND CONTINUE INTO SUNDAY. THE MODELS
ARE IN AGREEMENT BRINGING THIS SYSTEM THROUGH...BUT ARE NOT IN GOOD
AGREEMENT REGARDING THE DETAILS OF TIMING AND AMOUNT OF LOW LEVEL
WARM AIR THAT WILL BE IN PLACE. WE DID INCREASE POPS LATE SATURDAY
NIGHT INTO SUNDAY...AND MAY HAVE TO FURTHER. A MIX OF SNOW AND
RAIN...AND POSSIBLY SOME SLEET WILL BE POSSIBLE. SOME LIGHT SNOW
ACCUMULATIONS WILL BE POSSIBLE...MAINLY ALONG AND NORTHEAST OF
HIGHWAY 53.
WEAKER SYSTEMS ARE POSSIBLE SUNDAY NIGHT INTO TUESDAY WITH PERIODIC
CHANCES FOR SOME LIGHT PRECIPITATION. BOTH THE GFS AND ECMWF ARE
SHOWING A STRONGER AREA OF LOW PRESSURE AT THE END OF THE
PERIOD...AND INITIALLY LOOKS WARM ENOUGH FOR MOSTLY RAIN.
HIGH TEMPERATURES THROUGH MOST OF THE EXTENDED WILL BE ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1239 PM CDT THU MAR 26 2015
MUCH OF NE MINNESOTA AND NW WISCONSIN HAD VFR CONDITIONS WITH
LINGERING MVFR CEILINGS. WINDS WERE 10 TO 15 KNOTS FROM THE NORTH.
A CLEARING TREND WILL CONTINUE TODAY AS HIGH PRESSURE MOVES INTO
THE REGION. CLEAR SKIES AND VERY LIGHT WINDS WILL DEVELOP
TONIGHT...WHICH WILL CONTINUE THROUGH FRIDAY MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 30 13 30 14 / 10 0 0 10
INL 26 7 35 14 / 10 0 0 0
BRD 34 13 36 18 / 0 0 0 0
HYR 31 10 35 11 / 30 10 0 0
ASX 28 15 30 10 / 30 40 10 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CDT TONIGHT FOR WIZ004.
LS...NONE.
&&
$$
SHORT TERM...JJM
LONG TERM...MELDE
AVIATION...GROCHOCINSKI/WL
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
346 PM EDT THU MAR 26 2015
.SYNOPSIS...
RAIN WILL GRADUALLY CHANGE OVER TO A PERIOD OF SNOW BEFORE ENDING
TONIGHT. WE WILL REMAIN COLD FRIDAY WITH LINGERING SNOW AND RAIN
SHOWERS, ESPECIALLY IN NEW YORK STATE. A FEW SNOW SHOWERS ARE
POSSIBLE SATURDAY WITH HIGHS MAINLY IN THE 20S.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
240 PM UPDATE...
A WILD START TO THE DAY WITH THUNDER AND HAIL HERE AT THE OFFICE
AND ACROSS A GOOD CHUNK OF SOUTHERN NY. ATTENTION NOW TURNS TO
RAIN CHANGING TO SNOW, WITH THUNDER POTENTIAL STILL FAR SOUTHEAST.
RAIN TO SNOW....A THERMAL BOUNDARY ACROSS NORTHERN PA AND SULLIVAN
COUNTY IS ALLOWING FOR SOME IMPRESSIVE TEMP CHANGES. WE ARE 41 NOW
IN TOWANDA, BUT 56 JUST DOWN THE ROAD IN SCRANTON WITH SOME HINTS
OF SUNSHINE. MEANWHILE NORTH OF THIS BOUNDARY WHILE THUNDER MAY
HAVE GIVEN US SOUNDS OF SPRING THIS MORNING WE ARE ANYTHING BUT SPRING
LIKE. MID TO UPPER 30S IS THE RULE FROM THE NY/PA LINE NORTH AT THE
MOMENT AND TEMPS WILL HOLD STEADY OR SLOWLY FALL THROUGH EVENING.
FOR THE MOST PART WE ARE STILL SEEING JUST RAIN OVER OUR AREA BUT
HINTS OF A CHANGE TO SNOW ARE NOT FAR OFF. WE HAVE HAD A REPORT OF
SOME SNOW MIXING IN AT HORNELL LAST HOUR, AND WITH SNOW AT FULTON,
I SURMISE WE ARE GETTING SNOW OVER NORTHERN ONEIDA COUNTY ATTM. THE
LATEST RUC 850 MB OC LINE, ALONG WITH SURFACE TEMPS 36 DEGREES OR
COOLER SEEMS TO BE THE TRANSITION LINE TO AT LEAST A MIX OF SNOW.
THROUGH 0Z I SHOW A GRADUAL TRANSITION FROM RAIN TO A RAIN/SNOW
MIX. IN PERIODS OF HEAVIER PRECIPITATION IT WILL BE ALL SNOW,
DESPITE SURFACE TEMPS FOR THE MOST PART BEING IN THE 33-36 RANGE.
BASED ON WEB CAMS IN THE BUFFALO AREA NOW AND SURFACE TEMPS MAINLY
BEING ABOVE FREEZING, I SEE UP TO A SLUSHY INCH THROUGH 0Z MAINLY
ON GRASSY SURFACES ACROSS CENTRAL NY DOWN THROUGH THE FINGER
LAKES. MOST ROADS SHOULD BE PLENTY FINE WITH SUCH WARM BOUNDARY
LAYER TEMPS. THE EXCEPTION WILL BE ACROSS NORTHERN ONEIDA COUNTY
WHERE SLIGHTLY COLDER SURFACE TEMPS WILL ALLOW A COATING TO 2
INCHES. ALSO IN THE HILLS SOUTH OF SYRACUSE WE MAY BE CLOSER TO AN
INCH, THAN THE LOWER ELEVATIONS SUCH AS THE CITY. IN THESE TWO
AREAS, A LIGHT COATING CAN`T BE RULED OUT ON THE ROADS.
OVERNIGHT AS COLDER AIR WORKS INTO THE REST OF THE AREA, THE MAIN
AREA OF PRECIPITATION WILL BE PULLING EAST. WITH THAT IN MIND
EXPECT A GRADUAL RAIN TO SNOW MIX FOR MOST OF THE AREA BUT NOT
EXPECTING MORE THAN ANOTHER LIGHT COATING TO AN INCH AT MOST
TONIGHT. HIGHEST AMOUNTS WOULD BE IN NY STATE AND INTO THE
CATSKILLS WHERE THE FASTER CHANGEOVER WILL OCCUR.
THUNDER CHANCES...UNLIKE EARLIER WHERE WE SAW CONVECTIVE CHANCES
WITH A SURGE OF WARMER AIR IN THE MID LEVELS, OUR THUNDER CHANCES
LATE TODAY WILL BE AHEAD OF THE THERMAL BOUNDARY. THIS WILL LIMIT
CHANCES TO THE NEPA AND AT THAT, ONLY ISOLATED THUNDER AT BEST IS
EXPECTED.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
240 PM UPDATE...
FRIDAY/SATURDAY...AN UPPER LEVEL TROF WILL KEEP OUR WEATHER A BIT
UNSETTLED FRIDAY INTO THE FIRST PART OF SATURDAY, ALONG WITH
BRINGING ANOTHER ROUND OF COLD AIR TO THE REGION. HIGHEST CHANCES
FOR PRECIPITATION THROUGH SATURDAY WILL MAINLY BE IN NY STATE AND
MOSTLY IN THE FORM OF SNOW. SOME RAIN MAY MIX IN FRIDAY AFTERNOON
DUE TO A WARM BOUNDARY LAYER, ESPECIALLY FROM NEAR BINGHAMTON
SOUTH AND EAST. AS WE MENTIONED YESTERDAY IT WILL BE THE TEMPS
THAT WILL BE THE BIG STORY. MID 30S TO LOWER 40S FRIDAY WILL BE
OUR "WARM" DAY, ALTHOUGH STILL WELL BELOW NORMAL. HIGHS STRUGGLE
TO GET OUT OF THE 20S FOR MOST OF THE AREA SATURDAY.
SUNDAY...HIGH PRESSURE WILL KEEP OUR WEATHER QUIET. TEMPS MODERATE
BACK INTO THE 30S BUT STILL BELOW AVERAGE FOR LATE MARCH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
MEDIUM RANGE MODELS ARE IN FAIR AGREEMENT THROUGH THE EXTENDED
PERIOD INDICATING THE UPPER LEVEL TROF OVER ERN CANADA/US WILL
RELAX LATE IN THE PERIOD WITH A MORE ZONAL FLOW OVER THE CONUS.
SUNDAY NIGHT THROUGH MONDAY, SFC LOW PRES MOVING THROUGH EASTERN
CANADA WILL DRAG A COLD FRONT THROUGH THE REGION. INCLUDED CHC
POPS THROUGH THE PERIOD FOR MIXED RAIN/SNOW SHOWERS. MONDAY NIGHT
THROUGH WEDNESDAY LOOKS PRIMARILY DRY BUT A WEAK SYSTEM MAY IMPACT
THE AREA. NEXT SIGNIFICANT WEATHER MAKER WILL BE WED NIGHT THROUGH
THURSDAY AS ANOTHER FAST MOVING LOW TRACKS FROM THE UPPER GREAT
LAKES ACROSS THE US/CANADIAN BORDER INTO NRN NEW ENGLAND.
TEMPS WILL BEGIN BELOW NORMAL THEN RISE TO SEASONAL LEVELS LATE
IN THE PERIOD.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT WILL SLOWLY SINK SOUTH ACROSS THE REGION LATER THIS
AFTERNOON INTO THE EARLY EVENING HOURS AS SFC LOW PRES TRACKS
THROUGH EASTERN PA INTO COASTAL NEW ENGLAND. OVER THE NYS
TERMINALS RAIN WILL TRANSITION TO SNOW DURING THE MID/LATE
AFTERNOON FOLLOWED BY A 2-4 HOUR PERIOD OF SNOW BEFORE ENDING.
THROUGH EARLY EVENING WIDESPREAD IFR/BELOW ALT MIN CONDITIONS WILL
CONTINUE OVER THE NYS TERMINALS. OVERNIGHT, WEAK MIXING AND
ABUNDANT LOW LEVEL MOISTURE WILL RESULT IN PRIMARILY LOW MVFR CIGS
EXCEPT FOR IFR CIGS AT KITH/KBGM. ON FRIDAY CONDITIONS WILL
IMPROVE TO MVFR BY MID MORNING. AT KAVP, MVFR CONDITIONS IN LIGHT
RAIN WILL CONTINUE THROUGH 04Z. OVERNIGHT LOW MVFR CIGS WILL
CONTINUE WITH SLIGHT IMPROVEMENT TO MVFR BY MID MORNING.
LIGHT WINDS BECOMING NW AROUND 5 KNOTS LATE THIS AFTERNOON THROUGH
EARLY EVENING. NW WINDS AROUND 10 KNOTS ON FRIDAY.
.OUTLOOK...
FRI NIGHT...MVFR POSSIBLE IN SNOW SHOWERS.
SAT-SUN...VFR.
MONDAY/TUESDAY...RESTRICTIONS LIKELY IN RAIN/SNOW.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN
LONG TERM...RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
302 PM EDT THU MAR 26 2015
.SYNOPSIS...
RAIN WILL GRADUALLY CHANGE OVER TO A PERIOD OF SNOW BEFORE ENDING
TONIGHT. WE WILL REMAIN COLD FRIDAY WITH LINGERING SNOW AND RAIN
SHOWERS, ESPECIALLY IN NEW YORK STATE. A FEW SNOW SHOWERS ARE
POSSIBLE SATURDAY WITH HIGHS MAINLY IN THE 20S.
&&
.NEAR TERM /THROUGH TONIGHT/...
240 PM UPDATE...
A WILD START TO THE DAY WITH THUNDER AND HAIL HERE AT THE OFFICE
AND ACROSS A GOOD CHUNK OF SOUTHERN NY. ATTENTION NOW TURNS TO
RAIN CHANGING TO SNOW, WITH THUNDER POTENTIAL STILL FAR SOUTHEAST.
RAIN TO SNOW....A THERMAL BOUNDARY ACROSS NORTHERN PA AND SULLIVAN
COUNTY IS ALLOWING FOR SOME IMPRESSIVE TEMP CHANGES. WE ARE 41 NOW
IN TOWANDA, BUT 56 JUST DOWN THE ROAD IN SCRANTON WITH SOME HINTS
OF SUNSHINE. MEANWHILE NORTH OF THIS BOUNDARY WHILE THUNDER MAY
HAVE GIVEN US SOUNDS OF SPRING THIS MORNING WE ARE ANYTHING BUT SPRING
LIKE. MID TO UPPER 30S IS THE RULE FROM THE NY/PA LINE NORTH AT THE
MOMENT AND TEMPS WILL HOLD STEADY OR SLOWLY FALL THROUGH EVENING.
FOR THE MOST PART WE ARE STILL SEEING JUST RAIN OVER OUR AREA BUT
HINTS OF A CHANGE TO SNOW ARE NOT FAR OFF. WE HAVE HAD A REPORT OF
SOME SNOW MIXING IN AT HORNELL LAST HOUR, AND WITH SNOW AT FULTON,
I SURMISE WE ARE GETTING SNOW OVER NORTHERN ONEIDA COUNTY ATTM. THE
LATEST RUC 850 MB OC LINE, ALONG WITH SURFACE TEMPS 36 DEGREES OR
COOLER SEEMS TO BE THE TRANSITION LINE TO AT LEAST A MIX OF SNOW.
THROUGH 0Z I SHOW A GRADUAL TRANSITION FROM RAIN TO A RAIN/SNOW
MIX. IN PERIODS OF HEAVIER PRECIPITATION IT WILL BE ALL SNOW,
DESPITE SURFACE TEMPS FOR THE MOST PART BEING IN THE 33-36 RANGE.
BASED ON WEB CAMS IN THE BUFFALO AREA NOW AND SURFACE TEMPS MAINLY
BEING ABOVE FREEZING, I SEE UP TO A SLUSHY INCH THROUGH 0Z MAINLY
ON GRASSY SURFACES ACROSS CENTRAL NY DOWN THROUGH THE FINGER
LAKES. MOST ROADS SHOULD BE PLENTY FINE WITH SUCH WARM BOUNDARY
LAYER TEMPS. THE EXCEPTION WILL BE ACROSS NORTHERN ONEIDA COUNTY
WHERE SLIGHTLY COLDER SURFACE TEMPS WILL ALLOW A COATING TO 2
INCHES. ALSO IN THE HILLS SOUTH OF SYRACUSE WE MAY BE CLOSER TO AN
INCH, THAN THE LOWER ELEVATIONS SUCH AS THE CITY. IN THESE TWO
AREAS, A LIGHT COATING CAN`T BE RULED OUT ON THE ROADS.
OVERNIGHT AS COLDER AIR WORKS INTO THE REST OF THE AREA, THE MAIN
AREA OF PRECIPITATION WILL BE PULLING EAST. WITH THAT IN MIND
EXPECT A GRADUAL RAIN TO SNOW MIX FOR MOST OF THE AREA BUT NOT
EXPECTING MORE THAN ANOTHER LIGHT COATING TO AN INCH AT MOST
TONIGHT. HIGHEST AMOUNTS WOULD BE IN NY STATE AND INTO THE
CATSKILLS WHERE THE FASTER CHANGEOVER WILL OCCUR.
THUNDER CHANCES...UNLIKE EARLIER WHERE WE SAW CONVECTIVE CHANCES
WITH A SURGE OF WARMER AIR IN THE MID LEVELS, OUR THUNDER CHANCES
LATE TODAY WILL BE AHEAD OF THE THERMAL BOUNDARY. THIS WILL LIMIT
CHANCES TO THE NEPA AND AT THAT, ONLY ISOLATED THUNDER AT BEST IS
EXPECTED.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
240 PM UPDATE...
FRIDAY/SATURDAY...AN UPPER LEVEL TROF WILL KEEP OUR WEATHER A BIT
UNSETTLED FRIDAY INTO THE FIRST PART OF SATURDAY, ALONG WITH
BRINGING ANOTHER ROUND OF COLD AIR TO THE REGION. HIGHEST CHANCES
FOR PRECIPITATION THROUGH SATURDAY WILL MAINLY BE IN NY STATE AND
MOSTLY IN THE FORM OF SNOW. SOME RAIN MAY MIX IN FRIDAY AFTERNOON
DUE TO A WARM BOUNDARY LAYER, ESPECIALLY FROM NEAR BINGHAMTON
SOUTH AND EAST. AS WE MENTIONED YESTERDAY IT WILL BE THE TEMPS
THAT WILL BE THE BIG STORY. MID 30S TO LOWER 40S FRIDAY WILL BE
OUR "WARM" DAY, ALTHOUGH STILL WELL BELOW NORMAL. HIGHS STRUGGLE
TO GET OUT OF THE 20S FOR MOST OF THE AREA SATURDAY.
SUNDAY...HIGH PRESSURE WILL KEEP OUR WEATHER QUIET. TEMPS MODERATE
BACK INTO THE 30S BUT STILL BELOW AVERAGE FOR LATE MARCH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
2 AM UPDATE...
LITTLE CHANGE. FOLLOWED NEWEST WPC GUIDANCE. ONLY ADDITION TO
DISCUSSION BELOW IS THE LATE WEEK SYSTEM. A WARM FRONT WED NGT
FOLLOWED BY A COLD FRONT THURSDAY. MORE MIXED PRECIP BUT MOST
LOCATIONS RAIN TO SNOW.
PREVIOUS DISCUSSION...
UPPER LEVEL TROF WILL REMAIN OVER THE NORTHEAST THROUGH EARLY
NEXT WEEK BEFORE A MORE ZONAL FLOW DEVELOPS OVER THE CONUS. COOLER
THAN NORMAL WEATHER WILL CONTINUE UNTIL LATE IN THE PERIOD.
SURFACE HIGH PRES WILL PROVIDE FAIR BUT COOL WEATHER SATURDAY
NIGHT THROUGH SUNDAY. SUNDAY NIGHT THROUGH MONDAY, SFC LOW PRES
MOVING THROUGH EASTERN CANADA WILL DRAG A COLD FRONT THROUGH THE
AREA ON MONDAY. INCLUDED CHC POPS THROUGH THE PERIOD FOR MIXED
RAIN/SNOW SHOWERS. MONDAY NIGHT THROUGH TUESDAY NIGHT LOOKS
PRIMARILY DRY UNDER BRIEF SFC RIDGING BEFORE THE NEXT FRONT
APPROACHES THE NORTHEAST ON WEDNESDAY.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT WILL SLOWLY SINK SOUTH ACROSS THE REGION LATER THIS
AFTERNOON INTO THE EARLY EVENING HOURS AS SFC LOW PRES TRACKS
THROUGH EASTERN PA INTO COASTAL NEW ENGLAND. OVER THE NYS
TERMINALS RAIN WILL TRANSITION TO SNOW DURING THE MID/LATE
AFTERNOON FOLLOWED BY A 2-4 HOUR PERIOD OF SNOW BEFORE ENDING.
THROUGH EARLY EVENING WIDESPREAD IFR/BELOW ALT MIN CONDITIONS WILL
CONTINUE OVER THE NYS TERMINALS. OVERNIGHT, WEAK MIXING AND
ABUNDANT LOW LEVEL MOISTURE WILL RESULT IN PRIMARILY LOW MVFR CIGS
EXCEPT FOR IFR CIGS AT KITH/KBGM. ON FRIDAY CONDITIONS WILL
IMPROVE TO MVFR BY MID MORNING. AT KAVP, MVFR CONDITIONS IN LIGHT
RAIN WILL CONTINUE THROUGH 04Z. OVERNIGHT LOW MVFR CIGS WILL
CONTINUE WITH SLIGHT IMPROVEMENT TO MVFR BY MID MORNING.
LIGHT WINDS BECOMING NW AROUND 5 KNOTS LATE THIS AFTERNOON THROUGH
EARLY EVENING. NW WINDS AROUND 10 KNOTS ON FRIDAY.
.OUTLOOK...
FRI NIGHT...MVFR POSSIBLE IN SNOW SHOWERS.
SAT-SUN...VFR.
MONDAY/TUESDAY...RESTRICTIONS LIKELY IN RAIN/SNOW.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...HEDEN
NEAR TERM...HEDEN
SHORT TERM...HEDEN
LONG TERM...RRM/TAC
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 PM EDT THU MAR 26 2015
.SYNOPSIS...A COLD FRONT WILL TRACK SOUTHEAST THROUGH CENTRAL NORTH
CAROLINA LATE TONIGHT. THE COLD FRONT WILL BRIEFLY STALL OFFSHORE
THE CAROLINA COAST ON FRIDAY AS A POTENT UPPER LEVEL DISTURBANCE
APPROACHES FROM THE WEST.
&&
.NEAR TERM /TONIGHT/...
AS OF 315 PM THURSDAY...
LOWER HALF OF THE ATMOSPHERE HAS DRIED OUT AND HAS LOST MOST OF ITS
INSTABILITY COMPARED TO EARLIER THIS MORNING. RUC SOUNDINGS FOR 21Z
DEPICT A CAPPED ATMOSPHERE...MORE SO EAST HALF. SINCE ATMOSPHERE
WEAKLY CAPPED IN THE WEST-SW...COULD SEE AN ISOLATED SHOWER OR STORM
DEVELOP...OTHERWISE MOST OF CENTRAL NC SHOULD REMAIN SHOWER-FREE
WELL INTO THE EVENING. STEADY SW FLOW INTO THE EVENING WILL AID TO
KEEP TEMPS ON THE MILD SIDE THROUGH THE EVENING. MOST LOCALES SHOULD
REMAIN IN THE 60S THROUGH MOST OF THE EVENING HOURS.
RAIN CHANCES WILL BEGIN TO INCREASE SUBSTANTIALLY LATE THIS EVENING
AND MORE SO INTO THE OVERNIGHT HOURS AS SFC COLD FRONT SLIDES SEWD
ACROSS THE REGION. BULK OF SHOWERS WILL OCCUR BEHIND THE FRONT AS
MID-UPPER LEVEL TROUGH APPROACHES FROM THE WEST-SW...SETTING UP AN
OVERRUNNING SCENARIO. POPS WILL INCREASE TO CATEGORICAL
AROUND/SHORTLY AFTER MIDNIGHT NW HALF...AND ELSEWHERE DURING THE PRE-
DAWN HOURS.
MIN TEMPS FOR MOST FOLKS WILL NOT OCCUR UNTIL CLOSE TO OR SHORTLY
AFTER DAYBREAK AS COLD AIR ADVECTION WILL NOT COMMENCE UNTIL CLOSER
TO DAYBREAK. MIN TEMPS 40S TO NEAR 50 NORTH....50S TO NEAR 60 SOUTH.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 315 PM THURSDAY...
FRIDAY...WIDESPREAD SHOWERS IN THE MORNING WILL DIMINISH BY EARLY
AFTERNOON...COINCIDING WITH THE PASSAGE OF THE 850-700MB TROUGHS.
STRONG LOW LEVEL NLY FLOW WILL ADVECT COLDER AIR INTO THE REGION
THROUGHOUT THE DAY. TEMPS WILL CONTINUE TO FALL THROUGH THE MORNING
AND EARLY AFTERNOON HOURS...POSSIBLY STABILIZING BY MID AFTERNOON.
FRIDAY NIGHT...UPPER LEVEL TROUGH CROSSES THE REGION...ACCOMPANIED
BY A FEW SHOWERS. MODEL CROSS SECTIONS OF LIFT/MOISTURE DO DEPICT
ENOUGH SATURATION IN THE ICE NUCLEATION REGION TO CAUSE SNOW TO FORM
ALOFT. HOWEVER THE LOWER LAYERS ARE DRYING OUT TO SUCH A DEGREE THAT
ANY SNOW THAT FALLS WILL LIKELY MELT AND/OR EVAPORATE BEFORE
REACHING THE SURFACE. THUS WILL CONFINE MENTION OF PRECIP TO RAIN
SHOWERS FOR NOW. LOWER LAYERS OF THE ATMOSPHERE REMAIN WELL MIXED
THROUGH FRIDAY NIGHT. THIS MIXING ALONG WITH VARIABLY CLOUDY SKIES
MAY AID TO KEEP TEMPS UP A BIT IN SPITE OF THE COLD AIR ADVECTION.
SOME MOS GUIDANCE HAS MIN TEMPS BY EARLY SATURDAY IN THE UPPER 20S
TO AROUND 30 OVER THE PIEDMONT. THIS SEEMS A LITTLE EXTREME SO AM
MORE IN FAVOR OF MIN TEMPS NEAR FREEZING NW TO THE MID-UPPER 30S
ELSEWHERE. IF SKIES ARE ABLE TO CLEAR AND SFC WINDS DECOUPLE...COULD
SEE AN ARGUMENT FOR MIN TEMPS IN THE UPPER 20S-LOWER 30S.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...
THIS WEEKEND: THE MAIN WEATHER STORY THIS WEEKEND WILL BE THE COLD
TEMPERATURES... IN THE WAKE OF THE TROUGH THAT IS PROGGED TO PUSH
ACROSS OUR AREA EARLY IN THE PERIOD. COLD HIGH PRESSURE WILL BUILD
ACROSS OUR AREA FROM THE NW OVER THE WEEKEND...BRINGING AN AIRMASS
THAT FEATURES LOW LEVEL THICKNESSES ABOUT 60M BELOW NORMAL. DESPITE
MAINLY CLEAR SKIES AND AMPLE SUNSHINE DURING THE DAY...HIGHS
SATURDAY WILL ONLY CLIMB TO THE UPPER 40S NORTH TO LOWER 50S SOUTH.
SATURDAY NIGHT...LOOK FOR SUB-FREEZING LOW TEMPS ACROSS ALL OF
CENTRAL NC...THANKS TO THE COMBINATION OF THE AFOREMENTIONED
AIRMASS...MAINLY CLEAR SKIES AND CALM WIND UNDER THE HIGH PRESSURE
CENTER. RIGHT NOW WE`RE SHOWING LOWS RANGING FROM THE MID 20S ACROSS
THE TRIAD TO AROUND 30 ACROSS THE SOUTHERN COASTAL PLAIN...BUT WITH
THE HIGH CENTERED OVER US BY 12Z SUN...THOSE TEMPS MAY END UP EVEN
COLDER IN SPOTS. WE`LL BEGIN TO SEE SOME MODERATION ON SUNDAY AS THE
HIGH CENTER SHIFTS TO OUR SOUTHEAST...BUT STILL ABOUT 10 DEG BELOW
NORMAL...HIGHS IN THE MID 50S.
SUNDAY NIGHT THROUGH THURSDAY: A SHORT WAVE IS PROGGED TO QUICKLY
MOVE ACROSS OUR AREA SUNDAY NIGHT INTO MONDAY MORNING...BUT ASIDE
FROM A FEW PASSING SPRINKLES...RIGHT NOW IT APPEARS THAT FEATURE
WILL MOVE ACROSS MOSTLY DRY. HIGH PRESSURE WILL BRIEFLY BUILD ACROSS
OUR AREA LATE MONDAY INTO TUESDAY...PRIOR TO THE NEXT COLD FRONT
THAT IS PROGGED TO CROSS THE CAROLINAS ON WEDNESDAY. RIGHT NOW THAT
FRONT APPEARS TO COME THROUGH DRY AS WELL...GIVEN THAT THE DEEPER
MOISTURE AHEAD OF IT IS FORECAST TO REMAIN MOSTLY TO OUR SOUTH. RAIN
CHANCES MAY INCREASE ON THURSDAY AS THE FRONT LIFTS BACK TO OUR
NORTH AS A WARM FRONT AHEAD OF A FAST-MOVING SOUTHERN STREAM SHORT
WAVE. AS FOR TEMPERATURES DURING THIS TIME....LOOK FOR A GRADUAL
WARMUP...WITH READINGS CLOSER TO NORMAL THANKS TO THE PATTERN
DEAMPLIFYING AND BECOMING MORE ZONAL WITH TIME ACROSS OUR AREA.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 115 PM THURSDAY...
CURRENT MVFR TO LOW END VFR CONDITIONS WILL GRADUALLY BECOME VFR
ACROSS CENTRAL NC BY MID AFTERNOON AS DRIER AIR A FEW THOUSAND FEET
ALOFT MIXES DOWN TO THE SURFACE AND DIMINISH THE LOW CLOUD DECK. SFC
WINDS WILL BE BREEZY FROM THE SW WITH FREQUENT GUSTS BETWEEN 20-
24KTS.
A STRONG COLD FRONT WILL DROP SEWD ACROSS CENTRAL NC LATE TONIGHT
THROUGH EARLY FRIDAY MORNING. IFR-LIFR CONDITIONS WILL RETURN
IMMEDIATELY BEHIND THE FRONT WITH AREAS OF RAIN AND LOW CEILINGS.
THE FRONT SHOULD CROSS THE NORTHERN PIEDMONT AND NORTHERN COASTAL
PLAIN BETWEEN 07Z-10Z...AND THE SOUTHERN COUNTIES INCLUDING KFAY
BETWEEN 09Z-12Z. FRONTAL PASSAGE WILL BE NOTED BY SFC WINDS QUICKLY
VEERING TO A NLY DIRECTION AND BECOMING BLUSTERY WITH GUSTS 20-25KTS
PROBABLE.
THE ADVERSE AVIATION CONDITIONS WILL PERSIST THROUGH MUCH OF FRIDAY.
CONDITIONS ARE EXPECTED TO IMPROVE LATE FRIDAY NIGHT AND MORE SO
SATURDAY AS THE LOW LEVEL FLOW BECOMES NWLY AND ADVECTS A DRIER AIR
MASS INTO THE REGION. VFR CONDITIONS EXPECTED SATURDAY THROUGH
TUESDAY. THE ONLY EXCEPTION WILL BE A BRIEF PERIOD OF MVFR CEILINGS
ASSOCIATED WITH THE PASSAGE OF A COLD FRONT SUNDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...RAH
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
404 PM EDT THU MAR 26 2015
.SYNOPSIS...
SHOWERS AND ISOLATED THUNDERSTORMS WILL OCCUR AHEAD OF A STRONG
COLD FRONTAL SYSTEM THIS EVENING. A LARGE HIGH PRESSURE SYSTEM
WITH COLD AIR WILL DOMINATE OUR REGION INTO THE WEEKEND. THE UPPER
LEVEL FLOW BECOMES MORE ZONAL NEXT WEEK SO TEMPERATURES SHOULD
REBOUND TOWARD NORMAL.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
THE TONGUE OF WARM AIR HAS PUSHED 60F READINGS WELL INTO CENTRAL
PENNSYLVANIA WHILE COLD AIR REMAINS ENTRENCHED ALONG THE NY
BORDER WHERE IT IS STILL IN THE 30S. SNOW IS OCCURRING NOT TOO FAR
TO THE NORTH AND WEST.
THE MODELS AND RADAR INDICATED SHOWERS AND ISOLATE THUNDERSTORMS
WILL MOVE ACROSS THE STATE TODAY. BEST CHANCE OF THUNDER IN THE
WARM AIR FROM CENTRAL PA TO THE SOUTHEAST. THE HRRR CONTINUES TO
SHOW A CONVECTIVE LINE DEVELOPING IN CENTRAL PA IN THE 3-4 PM TIME
FRAME THEN THIS LINE MOVING EASTWARD CLEARING LANCASTER COUNTY BY
7-8 PM. THERE IS A CHANCE OF THUNDER OVER SOUTHEASTERN PA THIS
EVENING.
TOTAL QPF IS RELATIVELY LIGHT IN THE 0.05 TO 0.25 RANGE WITH HINTS
OF PERHAPS 0.25 TO 0.40 INCHES IN MORE INTENSE SHOWERS. ENSEMBLE
GUIDANCE IMPLIES RELATIVE TO HRRR/RAP IS ABOUT 0.10 TO 0.20
INCHES. NOT A BIG EVENT. MOST AREAS WILL LIKELY BE LUCKY TO SEE
ABOUT 0.10.
POPS DROP BEHIND THIS LINE AND THIS EVENING COLD AIR TURNS ANY
SHOWERS TO SNOW IN THE NORTHWEST. ALL NORTHERN AND WESTERN
MOUNTAIN AREAS SHOULD BE SNOW BY 10 PM. SNOW CHANGE OVER IS SLOWER
TO EAST AND IN NEXT PERIOD AND AFTER THE BULK OF THE FORECAST QPF.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM FRIDAY/...
.
THE COLD AIR AND GUSTY WINDS PUSH ACROSS OUR ENTIRE REGION THIS
OVERNIGHT. SOME PATCHY FOG IN SOUTHEAST. ANY RESIDUAL SHOWERS WILL
TURN TO SNOW SHOWERS OR FLURRIES.
BEST CHANCE OF A DUSTING OR LIGHT SNOW ACCUMULATIONS WOULD BE
OVERNIGHT IN NORTHWESTERN AREAS. BY MIDNIGHT TEMPERATURES WILL
RANGE 40S IN SOUTHEAST TO AROUND 30 IN NORTHWEST.
SOME SNOW SHOWER ACTIVITY POSSIBLE IN THE WEST FRIDAY. MORNING
LOWS MAINLY UPPER 20S IN NORTH TO LOW TO MID 30S IN SOUTHEAST.
STRONG COLD ADVECTION AND 850 HPA TEMPERATURES FORECAST TO FALL WELL
BELOW LATE FRIDAY INTO FRIDAY NIGHT...WILL BE UNSEASONABLY COLD
DAY FOR LATE MARCH. TEMPERATURES JUST ABOVE FREEZING IN MOUNTAINS
TO MID 40S IN LOWER SUSQUEHANNA VALLEY. THE COLDEST AIR AT 850
HPA WITH -2 TO -2.5 STANDARD DEVIATION ANOMALIES COMES BY FRIDAY
EVENING INTO SATURDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
UPPER TROF DEEPENING OVER THE EASTERN U.S. AT THE START OF THE
PERIOD WILL AFFECT THE WEATHER THROUGH AT LEAST THE EARLY PART OF
THE WEEKEND. SIGNIFICANT PRECIPITATION ASSOCIATED WITH THIS TROF
SHOULD HAVE CONCLUDED BY DAYTIME FRIDAY...BUT SEVERAL SHORTWAVES
ROTATING AROUND THE UPPER TROF WILL SLOW THE ADVANCE OF THE
OTHERWISE PROGRESSIVE TROF/ASSOCIATED SFC LOW...CAUSING LINGERING
SHOWERS INTO SATURDAY.
AREA OF HIGH PRESSURE SHOULD EVENTUALLY MOVE INTO THE REGION FOR
SUNDAY INTO EARLY NEXT WEEK.
BEHIND THE DEEP UPPER TROF WILL BRING ANOTHER SHOT UNSEASONABLY
COLD AIR INTO THE REGION...ESPECIALLY NOTICEABLE AFTER A COUPLE
DAYS OF MORE SPRING LIKE CONDS TODAY. TEMPERATURES WILL BE 10 TO
20 DEGREES BELOW NORMAL OVER THE WEEKEND.
A COMPARATIVELY WEAKER NRN STREAM WAVE WILL MOVE ACROSS THE UPPER
GREAT LAKES REGION AND TOWARDS THE NORTHEAST ON MONDAY. THIS WILL
CONTINUE THE CHILLY TEMPS AS WELL AS BRING THE CHANCE FOR MORE
SNOW SHOWERS. WEATHER WILL DRY OUT BUT REMAIN COOL FOR THE MIDDLE
OF NEXT WEEK AS ANOTHER AREA OF HIGH PRESSURE ARRIVES BEHIND
FRONT.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
KEY ISSUE OVER THE NEXT 24 HOURS IS THE TIMING OF THE FRONT AND
THE FRONTAL RAIN AND ISOLATED THUNDERSTORMS. THERE WILL ALSO BE
SOME ISSUES WITH RAIN TO SNOW IN NORTHWESTERN PA THIS EVENING.
THE BEST CHANCE FOR MODEST THUNDERSTORMS IS INT THE 20Z TO 00Z
TIMEFRAME MAINLY IN CENTRAL AND SOUTHEASTERN AREAS. THERE COULD BE
A WEAK LINE OF SHOWERS AND THUNDERSTORMS IN SOUTHEASTERN AREAS
THIS EVENING.
THE RAIN....SNOW....AND LINE OF SHOWERS WILL PRODUCE AREAS OF MVFR
AND IFR. BEHIND THE FRONTAL SYSTEM MOISTURE COULD PRODUCE SOME
AREAS OF PATCHY FOG AND AREAS OF SNOW SHOWERS IN THE
NORTHWEST...AREAS OF IFR AND MVFR.
THE COLD AIR COMES IN AND COULD CHANGE THE RAIN TO SNOW OVER THE
ENTIRE REGION BY FRIDAY. MAINLY VFR AND SOME AREAS MVFR IN SNOW
SHOWERS IN MOUNTAINS.
FRIDAY WILL BE A MOSTLY VFR AREAS MVFR IN SNSH. WINDY DAY WITH
SOME GUST SPREAD ISSUES.
OUTLOOK...
FRI-SAT...MVFR/IFR WITH SNOW SHOWERS NORTH/WEST. VFR TO MVFR CENTRAL
AND EAST WITH SCHC OF -SHRA.
SUN...NO SIG WX/VFR.
MON...CHANCE OF LIGHT RAIN /LIGHT SNOW EARLY/ ACROSS NW HALF WITH
MVFR REDUCTIONS. VFR SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/LAMBERT
NEAR TERM...GRUMM
SHORT TERM...GRUMM
LONG TERM...DEVOIR/GARTNER
AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
206 PM EDT THU MAR 26 2015
.SYNOPSIS...
SHOWERS AND ISOLATED THUNDERSTORMS WILL OCCUR AHEAD OF A STRONG
COLD FRONTAL SYSTEM THIS EVENING. A LARGE HIGH PRESSURE SYSTEM
WITH COLD AIR WILL DOMINATE OUR REGION INTO THE WEEKEND. THE UPPER
LEVEL FLOW BECOMES MORE ZONAL NEXT WEEK SO TEMPERATURES SHOULD
REBOUND TOWARD NORMAL.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
THE TONGUE OF WARM AIR HAS PUSHED 60F READINGS WELL INTO CENTRAL
PENNSYLVANIA WHILE COLD AIR REMAINS ENTRENCHED ALONG THE NY
BORDER WHERE IT IS STILL IN THE 30S. SNOW IS OCCURRING NOT TOO FAR
TO THE NORTH AND WEST.
THE MODELS AND RADAR INDICATED SHOWERS AND ISOLATE THUNDERSTORMS
WILL MOVE ACROSS THE STATE TODAY. BEST CHANCE OF THUNDER IN THE
WARM AIR FROM CENTRAL PA TO THE SOUTHEAST. THE HRRR CONTINUES TO
SHOW A CONVECTIVE LINE DEVELOPING IN CENTRAL PA IN THE 3-4 PM TIME
FRAME THEN THIS LINE MOVING EASTWARD CLEARING LANCASTER COUNTY BY
7-8 PM. THERE IS A CHANCE OF THUNDER OVER SOUTHEASTERN PA THIS
EVENING.
TOTAL QPF IS RELATIVELY LIGHT IN THE 0.05 TO 0.25 RANGE WITH HINTS
OF PERHAPS 0.25 TO 0.40 INCHES IN MORE INTENSE SHOWERS. ENSEMBLE
GUIDANCE IMPLIES RELATIVE TO HRRR/RAP IS ABOUT 0.10 TO 0.20
INCHES. NOT A BIG EVENT. MOST AREAS WILL LIKELY BE LUCKY TO SEE
ABOUT 0.10.
POPS DROP BEHIND THIS LINE AND THIS EVENING COLD AIR TURNS ANY
SHOWERS TO SNOW IN THE NORTHWEST. ALL NORTHERN AND WESTERN
MOUNTAIN AREAS SHOULD BE SNOW BY 10 PM. SNOW CHANGE OVER IS SLOWER
TO EAST AND IN NEXT PERIOD AND AFTER THE BULK OF THE FORECAST QPF.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM FRIDAY/...
.
THE COLD AIR AND GUSTY WINDS PUSH ACROSS OUR ENTIRE REGION THIS
OVERNIGHT. SOME PATCHY FOG IN SOUTHEAST. ANY RESIDUAL SHOWERS WILL
TURN TO SNOW SHOWERS OR FLURRIES.
BEST CHANCE OF A DUSTING OR LIGHT SNOW ACCUMULATIONS WOULD BE
OVERNIGHT IN NORTHWESTERN AREAS. BY MIDNIGHT TEMPERATURES WILL
RANGE 40S IN SOUTHEAST TO AROUND 30 IN NORTHWEST.
SOME SNOW SHOWER ACTIVITY POSSIBLE IN THE WEST FRIDAY. MORNING
LOWS MAINLY UPPER 20S IN NORTH TO LOW TO MID 30S IN SOUTHEAST.
STRONG COLD ADVECTION AND 850 HPA TEMPERATURES FORECAST TO FALL WELL
BELOW LATE FRIDAY INTO FRIDAY NIGHT...WILL BE UNSEASONABLY COLD
DAY FOR LATE MARCH. TEMPERATURES JUST ABOVE FREEZING IN MOUNTAINS
TO MID 40S IN LOWER SUSQUEHANNA VALLEY. THE COLDEST AIR AT 850
HPA WITH -2 TO -2.5 STANDARD DEVIATION ANOMALIES COMES BY FRIDAY
EVENING INTO SATURDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
DEEPENING BUT PROGRESSIVE UPPER TROF WILL BE MOVING EAST ACROSS
THE MID ATLANTIC STATES EARLY IN THE LONG TERM PERIOD. SIGNIFICANT
PRECIPITATION ASSOCIATED WITH THIS TROF SHOULD HAVE CONCLUDED BY
DAYTIME FRIDAY...BUT LINGERING SHOWERS ARE POSSIBLE INTO THE DAY
AS THE PUSH OF THE UPPER TROF HAS SLOWED A BIT IN RECENT GUIDANCE.
AT THE SFC...EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD INTO THE
REGION STARTING LATER FRIDAY WITH SEVERAL DRY DAYS INTO THE
WEEKEND.
THE DEEPNESS OF THIS UPPER TROF WILL BRING ANOTHER SHOT
UNSEASONABLY COLD AIR INTO THE REGION...ESPECIALLY NOTICEABLE
AFTER A COUPLE DAYS OF MORE SPRING LIKE CONDS WED AND THUR.
TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL OVER THE
WEEKEND.
A COMPARATIVELY WEAKER NRN STREAM WAVE WILL MOVE ACROSS THE UPPER
GREAT LAKES REGION AND TOWARDS THE NORTHEAST LATE SUNDAY INTO
MONDAY. THIS WILL CONTINUE THE CHILLY TEMPS AS WELL AS BRING THE
CHANCE FOR MORE SNOW SHOWERS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
KEY ISSUE OVER THE NEXT 24 HOURS IS THE TIMING OF THE FRONT AND
THE FRONTAL RAIN AND ISOLATED THUNDERSTORMS. THERE WILL ALSO BE
SOME ISSUES WITH RAIN TO SNOW IN NORTHWESTERN PA THIS EVENING.
THE BEST CHANCE FOR MODEST THUNDERSTORMS IS INT THE 20Z TO 00Z
TIMEFRAME MAINLY IN CENTRAL AND SOUTHEASTERN AREAS. THERE COULD BE
A WEAK LINE OF SHOWERS AND THUNDERSTORMS IN SOUTHEASTERN AREAS
THIS EVENING.
THE RAIN....SNOW....AND LINE OF SHOWERS WILL PRODUCE AREAS OF MVFR
AND IFR. BEHIND THE FRONTAL SYSTEM MOISTURE COULD PRODUCE SOME
AREAS OF PATCHY FOG AND AREAS OF SNOW SHOWERS IN THE
NORTHWEST...AREAS OF IFR AND MVFR.
THE COLD AIR COMES IN AND COULD CHANGE THE RAIN TO SNOW OVER THE
ENTIRE REGION BY FRIDAY. MAINLY VFR AND SOME AREAS MVFR IN SNOW
SHOWERS IN MOUNTAINS.
FRIDAY WILL BE A MOSTLY VFR AREAS MVFR IN SNSH. WINDY DAY WITH
SOME GUST SPREAD ISSUES.
OUTLOOK...
FRI-SAT...MVFR/IFR WITH SNOW SHOWERS NORTH/WEST. VFR TO MVFR CENTRAL
AND EAST WITH SCHC OF -SHRA.
SUN...NO SIG WX/VFR.
MON...CHANCE OF LIGHT RAIN /LIGHT SNOW EARLY/ ACROSS NW HALF WITH
MVFR REDUCTIONS. VFR SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/LAMBERT
NEAR TERM...GRUMM
SHORT TERM...GRUMM
LONG TERM...DEVOIR/GARTNER
AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
158 PM EDT THU MAR 26 2015
.SYNOPSIS...
SHOWERS AND ISOLATED THUNDERSTORMS WILL OCCUR AHEAD OF A STRONG
COLD FRONTAL SYSTEM THIS EVENING. A LARGE HIGH PRESSURE SYSTEM
WITH COLD AIR WILL DOMINATE OUR REGION INTO THE WEEKEND. THE UPPER
LEVEL FLOW BECOMES MORE ZONAL NEXT WEEK SO TEMPERATURES SHOULD
REBOUND TOWARD NORMAL.
&&
.NEAR TERM /UNTIL 10 PM THIS EVENING/...
THE TONGUE OF WARM AIR HAS PUSHED 60F READINGS WELL INTO CENTRAL
PENNSYLVANIA WHILE COLD AIR REMAINS ENTRENCHED ALONG THE NY
BORDER WHERE IT IS STILL IN THE 30S. SNOW IS OCCURRING NOT TOO FAR
TO THE NORTH AND WEST.
THE MODELS AND RADAR INDICATED SHOWERS AND ISOLATE THUNDERSTORMS
WILL MOVE ACROSS THE STATE TODAY. BEST CHANCE OF THUNDER IN THE
WARM AIR FROM CENTRAL PA TO THE SOUTHEAST. THE HRRR CONTINUES TO
SHOW A CONVECTIVE LINE DEVELOPING IN CENTRAL PA IN THE 3-4 PM TIME
FRAME THEN THIS LINE MOVING EASTWARD CLEARING LANCASTER COUNTY BY
7-8 PM. THERE IS A CHANCE OF THUNDER OVER SOUTHEASTERN PA THIS
EVENING.
TOTAL QPF IS RELATIVELY LIGHT IN THE 0.05 TO 0.25 RANGE WITH HINTS
OF PERHAPS 0.25 TO 0.40 INCHES IN MORE INTENSE SHOWERS. ENSEMBLE
GUIDANCE IMPLIES RELATIVE TO HRRR/RAP IS ABOUT 0.10 TO 0.20
INCHES. NOT A BIG EVENT. MOST AREAS WILL LIKELY BE LUCKY TO SEE
ABOUT 0.10.
POPS DROP BEHIND THIS LINE AND THIS EVENING COLD AIR TURNS ANY
SHOWERS TO SNOW IN THE NORTHWEST. ALL NORTHERN AND WESTERN
MOUNTAIN AREAS SHOULD BE SNOW BY 10 PM. SNOW CHANGE OVER IS SLOWER
TO EAST AND IN NEXT PERIOD AND AFTER THE BULK OF THE FORECAST QPF.
&&
.SHORT TERM /10 PM THIS EVENING THROUGH 6 PM FRIDAY/....
THE COLD AIR AND GUSTY WINDS PUSH ACROSS OUR ENTIRE REGION THIS
OVERNIGHT. SOME PATCHY FOG IN SOUTHEAST. ANY RESIDUAL SHOWERS WILL
TURN TO SNOW SHOWERS OR FLURRIES.
BEST CHANCE OF A DUSTING OR LIGHT SNOW ACCUMULATIONS WOULD BE
OVERNIGHT IN NORTHWESTERN AREAS. BY MIDNIGHT TEMPERATURES WILL
RANGE 40S IN SOUTHEAST TO AROUND 30 IN NORTHWEST.
SOME SNOW SHOWER ACTIVITY POSSBILE IN THE WEST FRIDAY. MORNING
LOWS MAINLY UPPER 20S IN NORTH TO LOW TO MID 30S IN SOUTHEAST.
STRONG COLD ADVECTION AND 850 HPA TEMPERATURES FORECAST TO FALL WELL
BELOW LATE FRIDAY INTO FRIDAY NIGHT...WILL BE UNSEASONABLY COLD
DAY FOR LATE MARCH. TEMPERATURES JUST ABOVE FREEZING IN MOUNTAINS
TO MID 40S IN LOWER SUSQUEHANNA VALLEY. THE COLDEST AIR AT 850
HPA WITH -2 TO -2.5 STANDARD DEVIATION ANOMALIES COMES BY FRIDAY
EVENING INTO SATURDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
DEEPENING BUT PROGRESSIVE UPPER TROF WILL BE MOVING EAST ACROSS
THE MID ATLANTIC STATES EARLY IN THE LONG TERM PERIOD. SIGNIFICANT
PRECIPITATION ASSOCIATED WITH THIS TROF SHOULD HAVE CONCLUDED BY
DAYTIME FRIDAY...BUT LINGERING SHOWERS ARE POSSIBLE INTO THE DAY
AS THE PUSH OF THE UPPER TROF HAS SLOWED A BIT IN RECENT GUIDANCE.
AT THE SFC...EXPANSIVE AREA OF HIGH PRESSURE WILL BUILD INTO THE
REGION STARTING LATER FRIDAY WITH SEVERAL DRY DAYS INTO THE
WEEKEND.
THE DEEPNESS OF THIS UPPER TROF WILL BRING ANOTHER SHOT
UNSEASONABLY COLD AIR INTO THE REGION...ESPECIALLY NOTICEABLE
AFTER A COUPLE DAYS OF MORE SPRING LIKE CONDS WED AND THUR.
TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL OVER THE
WEEKEND.
A COMPARATIVELY WEAKER NRN STREAM WAVE WILL MOVE ACROSS THE UPPER
GREAT LAKES REGION AND TOWARDS THE NORTHEAST LATE SUNDAY INTO
MONDAY. THIS WILL CONTINUE THE CHILLY TEMPS AS WELL AS BRING THE
CHANCE FOR MORE SNOW SHOWERS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
ISOLATED SHOWERS MOVING INTO WESTERN SECTIONS. SOME AREAS
STILL NEAR FREEZING. WILL CONTINUE TO MONITOR ABD UPDATE
AS NEEDED. 12Z TAFS WILL BE OUT SHORTLY.
UPDATED THE TAFS TO REFLECT THE SURGE OF WARM AIR AND THE
POTENTIAL SHOWERS AND MENTION OF VCTS IN SOUTHEASTERN AREAS THIS
AFTERNOON AND EVENING.
MVFR WILL LIKELY HOLD NEAR NY BORDER AND PERIODS OF VFR LIKELY
IN SOUTH-CENTRAL PA AS THE WARM AIR HAS SCOURED OUT THE LOW-LEVEL
COLD AIR. BUT THE FAST APPROACHING FRONT WILL BRING SHOWERS AND
MVFR/IFR TO THE REGION THIS AFTERNOON AND EVENING.
BEHIND THE FRONT MOST AREAS WILL GO UP OVERNIGHT MAINLY TO VFR AND
PATCHY MVFR. BUT IN THE SOUTHEAST COULD SEE SOME AREAS IFR/MVFR
BEFORE SUNRISE WITH PATCHY FOGGY DEVELOPING.
OUTLOOK...
FRI-SAT...MVFR/IFR WITH SNOW SHOWERS NORTH/WEST. VFR TO MVFR CENTRAL
AND EAST WITH SCHC OF -SHRA.
SUN...NO SIG WX/VFR.
MON...CHANCE OF LIGHT RAIN /LIGHT SNOW EARLY/ ACROSS NW HALF WITH
MVFR REDUCTIONS. VFR SE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM/LAMBERT
NEAR TERM...GRUMM
SHORT TERM...GRUMM
LONG TERM...DEVOIR/GARTNER
AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
414 PM EDT THU MAR 26 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE WESTERN CAROLINAS AND NORTHEAST GEORGIA
TONIGHT. A TRAILING UPPER LEVEL DISTURBANCE WILL THEN CROSS THE AREA
FRIDAY THROUGH FRIDAY NIGHT. DRY AND COOL HIGH PRESSURE WILL SETTLE
IN OVER THE WEEKEND. A LOW PRESSURE CLIPPER SYSTEM AND ASSOCIATED
COLD FRONT WILL PASS OVER THE REGION ON MONDAY.
&&
.NEAR TERM /THROUGH FRIDAY/...
2015 UTC UPDATE...POPS WERE LOWERED THE NEXT FEW HOURS BASED ON
RADAR TRENDS...AND THUNDER CHANCES BASED ON THE LATEST MODEL DATA.
SKY COVER WAS UPDATED FROM VISIBLE SATELLITE IMAGERY.
AS OF 225 PM...CLOUDS HAVE THINNED AND BROKEN UP AROUND THE AREA
WHICH SHOULD ALLOW TEMPS TO RISE INTO THE 70S ACRS MUCH OF THE
PIEDMONT AND UPPER 60S IN MTN VALLEYS. HELD ONTO A LOW POP THRU
EARLY EVENING...WITH LATEST SOUNDINGS HAVING A SMALL AMOUNT OF
INSTABILITY ACRS THE PIEDMONT...ALBEIT CAPPED OFF IN THE MIDLEVELS.
THE CHANCE OF THUNDER IN THESE AREAS LOOKS NEAR ZERO THRU THE REST
OF THE DAYTIME HRS.
LOOKING UPSTREAM...DEEP TROUGH CONTINUES TO DIG INTO THE MID
MISSISSIPPI VALLEY...PRECEDED BY A FAIRLY POTENT COLD FRONT AND AN
WAVE OF LOW PRESSURE OVER THE CENTRAL APPALACHIANS. A BAND OF
CONVECTIVE PRECIP AND EMBEDDED TSTMS IS SEEN OVER WV AND ERN
KY...JUST AHEAD OF THE SFC FRONT. LATEST HRRR AND 4KM SPC WRF TAKE
THIS FEATURE NEWD...WHILE MORE ACTIVITY DEVELOPS ALONG THE FRONT
OVER THE TENN VALLEY. THE FRONT IS EXPECTED TO SLOWLY MOVE ACRS THE
MTNS OVERNIGHT AS THE TROUGH DIGS AND THE SFC WAVE MOVES TO THE MID
ATLANTIC COAST. BOTH THE CONVECTION ALLOWING MODELS AS WELL AS THE
GFS/NAM SHOW QPF IN OUR CWFA INVOF THE FRONT...THOUGH THIS APPEARS
DUE TO REDEVELOPMENT RATHER THAN ADVECTION OF THE CURRENT ACTIVITY.
INDEED MOST GUIDANCE SHOWS MODEST INSTABILITY OF UP TO A FEW HUNDRED
J/KG...MAINLY ELEVATED IN NATURE...PRESENT IN THE CWFA PRIOR TO THE
FRONT. THUNDER CHANCES ARE MAINLY CONFINED TO THE MTNS AND AREAS
SOUTH OF I-85. THOUGH 0-3KM SHEAR WOULD SUGGEST SOME ORGANIZATION OR
DMGG WIND THREAT WITH TSRA...THE EFFECTIVE SHEAR IS SMALL AND SVR WX
IS NOT ANTICIPATED. SPC DOES NOT HAVE THE CWFA IN ANY PROBABILISTIC
THREAT AREAS THRU 12Z. DESPITE THE FRONT ARRIVING LATE...MINS WILL
BE A COUPLE CATEGORIES ABOVE CLIMO.
COLD AIR BEGINS TO SWEEP IN BEHIND THE FRONT...AND NWLY WINDS WILL
STILL HAVE SOME MOISTURE TO WORK WITH. SMALL CHANCES OF NW FLOW SNOW
ARE INCLUDED NEAR DAYBREAK...THOUGH IN REALITY IF THE COLD AIR
ARRIVES EARLY ENOUGH A MIX OF PTYPES COULD OCCUR AS IT CUTS
UNDERNEATH THE VERY WARM MIDLEVEL AIR STILL PRESENT...CREATING A
WARM NOSE. PRECIP CHANCES WILL GENERALLY TREND DOWNWARD IN THE WAKE
OF THE FRONT AS THE DAY PROGRESSES...BUT SOME DEGREE OF UPPER
DYNAMIC FORCING WILL BE PRESENT WITH THE TROUGH STILL JUST TO OUR
WEST. MIDLEVEL LAPSE RATES IMPROVE SUFFICIENTLY TO ALLOW SLIGHT SFC
BASED INSTABILITY BY AFTN. THESE INGREDIENTS COULD PRODUCE SOME
SPOTTY SHOWERS...WITH TEMPS AGAIN BECOMING SUPPORTIVE OF SNOW OR A
RA/SN MIX IN THE HIGH ELEVATIONS BY SUNSET. EARLY AFTN MAX TEMPS
WILL MAINLY BE IN THE 50S IN THE PIEDMONT AND MTN VALLEYS...WITH
UPPER 30S AND LOWER 40S IN THE HIGH ELEVATIONS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 145 PM THURSDAY..A DEEP UPPER TROUGH CENTERED WEST OF THE AREA
FRIDAY EVENING IS FORECAST TO SWING THROUGH THE AREA BY EARLY
SATURDAY AND MOVE INTO THE ATLANTIC EARLY SUNDAY. IN THE WAKE OF THE
TROUGH...WEAK RIDGING WILL OCCUR ACROSS THE SE STATES ON SUNDAY.
ON FRIDAY NIGHT...THERE MAY BE SOME LINGERING SHOWERS ACROSS THE
PIEDMONT ALONG THE AXIS OF A DEPARTING VORT MAX...SO HAVE MAINTAINED
A MENTION OF CHANCE POPS THERE BEFORE MIDNIGHT. ALSO...SOME NW FLOW
SNOW WILL LIKELY BE ON GOING AS ANOTHER VORT MAX CROSSES THE
MOUNTAINS AHEAD OF THE APPROACHING BASE OF THE UPPER TROF.
MEANWHILE...850 MB TEMPS WILL FALL TO THE -8C TO -12C RANGE BY 12Z
SATURDAY. HENCE...A PERIOD OF DECENT NW FLOW SNOW SHOULD OCCUR
FRIDAY NIGHT. IN REGARD TO SNOW ACCUMS...THE LATEST MODEL CONSENSUS
OF QPF HAS TICKED UPWARD SOMEWHAT SO THAT ADVISORY TYPE SNOWFALL MAY
OCCUR IN THE SMOKIES. SNOW ACCUMULATIONS WILL BE ON THE ORDER OF 2-3
INCHES IN SMOKIES WITH GENERALLY 1-2 INCHES ELSEWHERE IN THE TN
BORDER COUNTIES.
IN ADDITION...IT IS LOOKING LIKE THE MOUNTAINS WILL EXPERIENCE AN
ADVECTIVE FREEZE FRIDAY NIGHT...WITH LOW TEMPS IN THE 20S. THE
PIEDMONT WILL SEE TEMPS IN THE 30S...WITH ISOLD FREEZING TEMPS AND
POSSIBLY SOME PATCHY FROST WHERE WINDS CAN DECOUPLE IN SHELTERED
AREAS.
NW FLOW AND COLD AIR ADVENTION WILL CONTINUE ON SATURDAY AS THE CP
HIGH REMAINS WEST OF THE AREA. HOWEVER...ENOUGH DRY AIR ARRIVES TO
CUT OFF THE SNOW SHOWER ACTIVITY IN THE MOUNTAINS EARLY SAT. HIGHS
SATURDAY WILL REMAIN CHILLY WITH HIGHS 15-20 DEGREES BELOW CLIMO.
THE CP HIGH WILL SETTLE OVER THE AREA FRIDAY NIGHT PRODUCING IDEAL
RADIATIVE COOLING CONDITIONS. A HARD FREEZE IS EXPECTED ACROSS ALL
OF THE MOUNTAINS...WITH FREEZING TEMPS ALSO EXPECTED OUTSIDE THE
MOUNTAINS. MIN TEMPS SUNDAY MORNING LOOK TO BE IN THE TEENS TO MID
20S IN THE MTNS AND MID 20S TO LWR 30S ACRS THE PIEDMONT. THESE MIN
TEMPS WILL APPROACH RECORD LOWS ACRS THE PIEDMONT (SEE CLIMATE
SECTION BELOW).
EVEN WITH PLENTY OF SUNSHINE AND WEAK WARM ADVECTION RETURING ON
SUNDAY...MAX TEMPS ARE STILL EXPECTED TO BE A COUPLE CATEGORIES
BELOW CLIMO.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 140 PM THURSDAY...THE MEDIUM RANGE BEGINS WITH A PROGRESSIVE
TROUGH AND ATTENDANT FRONTAL BOUNDARY MOVING ACROSS THE EASTERN
STATES IN THE SUNDAY NIGHT/MONDAY TIME FRAME. THIS WILL SUPPORT
CHANCE POPS ACROSS THE MTNS BY 12Z MONDAY. UPPER FORCING IS EXPECTED
TO PASS NORTH OF THE REGION...AS FRONTAL ZONE BEGINS TO SLOW DOWN
ACROSS THE SOUTHERN APPALACHIANS. THE RESULT IN VEERING LOW LEVEL
FLOW IN THE VICINITY OF THE FRONT...WITH RESULTANT WEAKLY
CONVERGENT/DOWNSLOPE FLOW LIMITING THE PRECIP POTENTIAL OUTSIDE THE
MTNS...AND POPS WILL GENERALLY BE MAINTAINED IN THE SLIGHT CHANCE
RANGE THERE.
FOR THE REMAINDER OF THE PERIOD...WESTERN HEIGHT FALLS AND EASTERN
RISES IN THE WAKE OF THE DEPARTING TROUGH WILL RESULT IN
ESTABLISHMENT OF FAST/QUASI-ZONAL FLOW ACROSS MUCH OF THE CONUS
THROUGH THE MIDDLE PART OF NEXT WEEK. MEANWHILE...THE AFOREMENTIONED
BAROCLINIC ZONE WILL BECOME QUASI-STATIONARY WITHIN THIS FLOW
PATTERN. IT IS THEREFORE NOT SURPRISING THAT GLOBAL MODEL DETAILS
DIVERGE DURING THIS TIME FRAME...AS THEY STRUGGLE TO RESOLVE WEAK
SHORT WAVES RIPPLING THROUGH THIS LOW AMPLITUDE PATTERN. THE GFS
OFFERS THE WETTER SOLUTION...WITH AT LEAST A COUPLE OF WEAK WAVES
SPREADING LIGHT PRECIP INTO THE REGION PRIOR TO THE ARRIVAL OF
ANOTHER FRONTAL SYSTEM LATE IN THE WEEK. THE ECMWF IS QUITE A BIT
DRIER. CONSIDERING THE PATTERN...IT PROBABLY BEHOOVES US TO MAINTAIN
AT LEAST A SLIGHT CHANCE POP DURING MOST PERIODS OF THE MEDIUM
RANGE...WITH THE HIGHEST POPS RESERVED FOR DAY 7 FOR THE POTENTIAL
APPROACH OF THE NEXT FRONTAL SYSTEM.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
AT KCLT...A SMALL CHANCE OF PRECIP EXISTS THIS AFTN...THOUGH TOO
SMALL TO MENTION. ANY PRECIP WOULD BE CONVECTIVE IN NATURE BUT
LATEST NAM/RAP SOUNDINGS ARE CAPPED IN THE MIDLEVELS...SO
PARTICULARLY DEEP CONVECTION OR THUNDER NOT EXPECTED. SWLY WINDS
WILL OCCASIONALLY GUST TO NEAR 20 KT. COLD FRONT WILL APPROACH FROM
THE NW TONIGHT...WITH WSHFT TO NW LIKELY 08-09Z. LLVL FORCING IN THE
PRESENCE OF ABUNDANT MOISTURE IS LIKELY TO BRING POPS AFTER MIDNIGHT
IF NOT SOONER. SOME ELEVATED INSTABILITY WILL STILL BE
PRESENT...HENCE PROB30 TSRA. IFR CANNOT BE RULED OUT IF A TSRA DOES
PASS OVER THE FIELD. CIGS ARE EXPECTED TO BOTTOM OUT AT LOW MVFR
INVOF THE FRONT...WITH POPS DIMINISHING AND CIGS GRADUALLY LIFTING
AFTER DAYBREAK.
ELSEWHERE...MAINLY VFR LEVEL CLOUDS WILL BE SEEN THIS AFTN WITH
SPOTTY CU AT MVFR LEVELS...THOUGH CIGS SHOULD REMAIN VFR. SMALL POPS
WILL CONTINUE THRU THE AFTN THOUGH TOO LOW TO MENTION. IN GENERAL
TRENDS OVERNIGHT WITH THE FROPA WILL BE SIMILAR TO KCLT...THOUGH THE
NWLY SHIFT WILL OCCUR AS EARLY AS 02-03Z AT KAVL AND OCCURRING AT
ALL SITES BEFORE DAWN. THUNDER CHANCES AHEAD OF THE FRONT EXIST
MAINLY AT THE UPSTATE SC SITES. GUIDANCE SPLIT ON FLT CATEGORY
OVERNIGHT BUT MVFR SEEMS MOST LIKELY GIVEN RELATIVELY LIGHT PRECIP
AND WINDS KEEPING THE BDY LAYER MIXED. KAND IS AN EXCEPTION WHERE
THE SIGNAL IS STRONGER FOR IFR. TSRA MIGHT PRODUCE BRIEF IFR
WHEREVER THEY OCCUR. IMPROVING CONDITIONS INTO MIDDAY FRI WITH
CONTINUED NWLY WINDS AND OCNL LOW END GUSTS.
OUTLOOK...SCATTERED SHOWERS MAY PRODUCE SOME RESTRICTIONS FRI AFTN.
HIGH PRESSURE WILL BUILD OVER THE REGION BEGINNING FRIDAY NIGHT
PRODUCING VFR CONDITIONS. A WEAK FRONT PASSING THRU SUNDAY NIGHT MAY
PRODUCE A FEW RESTRICTIONS BUT VFR SHOULD RETURN IN ITS WAKE.
CONFIDENCE TABLE...
20-02Z 02-08Z 08-14Z 14-18Z
KCLT HIGH 100% HIGH 100% HIGH 82% HIGH 95%
KGSP HIGH 100% HIGH 100% HIGH 86% MED 62%
KAVL HIGH 100% HIGH 87% HIGH 96% HIGH 82%
KHKY HIGH 96% HIGH 100% MED 73% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 82% MED 62%
KAND HIGH 98% HIGH 100% MED 64% MED 72%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MINIMUM TEMPERATURES FOR MARCH 28TH...
GSP 26 1982
CLT 25 1982
AVL 11 1887
RECORD MINIMUM TEMPERATURES FOR MARCH 29TH...
GSP 26 1899
CLT 26 2013
AVL 19 1982
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...RWH
NEAR TERM...JAT/WIMBERLEY
SHORT TERM...LG
LONG TERM...JDL
AVIATION...WIMBERLEY
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
247 PM EDT THU MAR 26 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE WESTERN CAROLINAS AND NORTHEAST GEORGIA
TONIGHT. A TRAILING UPPER LEVEL DISTURBANCE WILL THEN CROSS THE AREA
FRIDAY THROUGH FRIDAY NIGHT. DRY AND COOL HIGH PRESSURE WILL SETTLE
IN OVER THE WEEKEND. A LOW PRESSURE CLIPPER SYSTEM AND ASSOCIATED
COLD FRONT WILL PASS OVER THE REGION ON MONDAY.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 225 PM...CLOUDS HAVE THINNED AND BROKEN UP AROUND THE AREA
WHICH SHOULD ALLOW TEMPS TO RISE INTO THE 70S ACRS MUCH OF THE
PIEDMONT AND UPPER 60S IN MTN VALLEYS. HELD ONTO A LOW POP THRU
EARLY EVENING...WITH LATEST SOUNDINGS HAVING A SMALL AMOUNT OF
INSTABILITY ACRS THE PIEDMONT...ALBEIT CAPPED OFF IN THE MIDLEVELS.
THE CHANCE OF THUNDER IN THESE AREAS LOOKS NEAR ZERO THRU THE REST
OF THE DAYTIME HRS.
LOOKING UPSTREAM...DEEP TROUGH CONTINUES TO DIG INTO THE MID
MISSISSIPPI VALLEY...PRECEDED BY A FAIRLY POTENT COLD FRONT AND AN
WAVE OF LOW PRESSURE OVER THE CENTRAL APPALACHIANS. A BAND OF
CONVECTIVE PRECIP AND EMBEDDED TSTMS IS SEEN OVER WV AND ERN
KY...JUST AHEAD OF THE SFC FRONT. LATEST HRRR AND 4KM SPC WRF TAKE
THIS FEATURE NEWD...WHILE MORE ACTIVITY DEVELOPS ALONG THE FRONT
OVER THE TENN VALLEY. THE FRONT IS EXPECTED TO SLOWLY MOVE ACRS THE
MTNS OVERNIGHT AS THE TROUGH DIGS AND THE SFC WAVE MOVES TO THE MID
ATLANTIC COAST. BOTH THE CONVECTION ALLOWING MODELS AS WELL AS THE
GFS/NAM SHOW QPF IN OUR CWFA INVOF THE FRONT...THOUGH THIS APPEARS
DUE TO REDEVELOPMENT RATHER THAN ADVECTION OF THE CURRENT ACTIVITY.
INDEED MOST GUIDANCE SHOWS MODEST INSTABILITY OF UP TO A FEW HUNDRED
J/KG...MAINLY ELEVATED IN NATURE...PRESENT IN THE CWFA PRIOR TO THE
FRONT. THUNDER CHANCES ARE MAINLY CONFINED TO THE MTNS AND AREAS
SOUTH OF I-85. THOUGH 0-3KM SHEAR WOULD SUGGEST SOME ORGANIZATION OR
DMGG WIND THREAT WITH TSRA...THE EFFECTIVE SHEAR IS SMALL AND SVR WX
IS NOT ANTICIPATED. SPC DOES NOT HAVE THE CWFA IN ANY PROBABILISTIC
THREAT AREAS THRU 12Z. DESPITE THE FRONT ARRIVING LATE...MINS WILL
BE A COUPLE CATEGORIES ABOVE CLIMO.
COLD AIR BEGINS TO SWEEP IN BEHIND THE FRONT...AND NWLY WINDS WILL
STILL HAVE SOME MOISTURE TO WORK WITH. SMALL CHANCES OF NW FLOW SNOW
ARE INCLUDED NEAR DAYBREAK...THOUGH IN REALITY IF THE COLD AIR
ARRIVES EARLY ENOUGH A MIX OF PTYPES COULD OCCUR AS IT CUTS
UNDERNEATH THE VERY WARM MIDLEVEL AIR STILL PRESENT...CREATING A
WARM NOSE. PRECIP CHANCES WILL GENERALLY TREND DOWNWARD IN THE WAKE
OF THE FRONT AS THE DAY PROGRESSES...BUT SOME DEGREE OF UPPER
DYNAMIC FORCING WILL BE PRESENT WITH THE TROUGH STILL JUST TO OUR
WEST. MIDLEVEL LAPSE RATES IMPROVE SUFFICIENTLY TO ALLOW SLIGHT SFC
BASED INSTABILITY BY AFTN. THESE INGREDIENTS COULD PRODUCE SOME
SPOTTY SHOWERS...WITH TEMPS AGAIN BECOMING SUPPORTIVE OF SNOW OR A
RA/SN MIX IN THE HIGH ELEVATIONS BY SUNSET. EARLY AFTN MAX TEMPS
WILL MAINLY BE IN THE 50S IN THE PIEDMONT AND MTN VALLEYS...WITH
UPPER 30S AND LOWER 40S IN THE HIGH ELEVATIONS.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 145 PM THURSDAY..A DEEP UPPER TROUGH CENTERED WEST OF THE AREA
FRIDAY EVENING IS FORECAST TO SWING THROUGH THE AREA BY EARLY
SATURDAY AND MOVE INTO THE ATLANTIC EARLY SUNDAY. IN THE WAKE OF THE
TROUGH...WEAK RIDGING WILL OCCUR ACROSS THE SE STATES ON SUNDAY.
ON FRIDAY NIGHT...THERE MAY BE SOME LINGERING SHOWERS ACROSS THE
PIEDMONT ALONG THE AXIS OF A DEPARTING VORT MAX...SO HAVE MAINTAINED
A MENTION OF CHANCE POPS THERE BEFORE MIDNIGHT. ALSO...SOME NW FLOW
SNOW WILL LIKELY BE ON GOING AS ANOTHER VORT MAX CROSSES THE
MOUNTAINS AHEAD OF THE APPROACHING BASE OF THE UPPER TROF.
MEANWHILE...850 MB TEMPS WILL FALL TO THE -8C TO -12C RANGE BY 12Z
SATURDAY. HENCE...A PERIOD OF DECENT NW FLOW SNOW SHOULD OCCUR
FRIDAY NIGHT. IN REGARD TO SNOW ACCUMS...THE LATEST MODEL CONSENSUS
OF QPF HAS TICKED UPWARD SOMEWHAT SO THAT ADVISORY TYPE SNOWFALL MAY
OCCUR IN THE SMOKIES. SNOW ACCUMULATIONS WILL BE ON THE ORDER OF 2-3
INCHES IN SMOKIES WITH GENERALLY 1-2 INCHES ELSEWHERE IN THE TN
BORDER COUNTIES.
IN ADDITION...IT IS LOOKING LIKE THE MOUNTAINS WILL EXPERIENCE AN
ADVECTIVE FREEZE FRIDAY NIGHT...WITH LOW TEMPS IN THE 20S. THE
PIEDMONT WILL SEE TEMPS IN THE 30S...WITH ISOLD FREEZING TEMPS AND
POSSIBLY SOME PATCHY FROST WHERE WINDS CAN DECOUPLE IN SHELTERED
AREAS.
NW FLOW AND COLD AIR ADVENTION WILL CONTINUE ON SATURDAY AS THE CP
HIGH REMAINS WEST OF THE AREA. HOWEVER...ENOUGH DRY AIR ARRIVES TO
CUT OFF THE SNOW SHOWER ACTIVITY IN THE MOUNTAINS EARLY SAT. HIGHS
SATURDAY WILL REMAIN CHILLY WITH HIGHS 15-20 DEGREES BELOW CLIMO.
THE CP HIGH WILL SETTLE OVER THE AREA FRIDAY NIGHT PRODUCING IDEAL
RADIATIVE COOLING CONDITIONS. A HARD FREEZE IS EXPECTED ACROSS ALL
OF THE MOUNTAINS...WITH FREEZING TEMPS ALSO EXPECTED OUTSIDE THE
MOUNTAINS. MIN TEMPS SUNDAY MORNING LOOK TO BE IN THE TEENS TO MID
20S IN THE MTNS AND MID 20S TO LWR 30S ACRS THE PIEDMONT. THESE MIN
TEMPS WILL APPROACH RECORD LOWS ACRS THE PIEDMONT (SEE CLIMATE
SECTION BELOW).
EVEN WITH PLENTY OF SUNSHINE AND WEAK WARM ADVECTION RETURING ON
SUNDAY...MAX TEMPS ARE STILL EXPECTED TO BE A COUPLE CATEGORIES
BELOW CLIMO.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 140 PM THURSDAY...THE MEDIUM RANGE BEGINS WITH A PROGRESSIVE
TROUGH AND ATTENDANT FRONTAL BOUNDARY MOVING ACROSS THE EASTERN
STATES IN THE SUNDAY NIGHT/MONDAY TIME FRAME. THIS WILL SUPPORT
CHANCE POPS ACROSS THE MTNS BY 12Z MONDAY. UPPER FORCING IS EXPECTED
TO PASS NORTH OF THE REGION...AS FRONTAL ZONE BEGINS TO SLOW DOWN
ACROSS THE SOUTHERN APPALACHIANS. THE RESULT IN VEERING LOW LEVEL
FLOW IN THE VICINITY OF THE FRONT...WITH RESULTANT WEAKLY
CONVERGENT/DOWNSLOPE FLOW LIMITING THE PRECIP POTENTIAL OUTSIDE THE
MTNS...AND POPS WILL GENERALLY BE MAINTAINED IN THE SLIGHT CHANCE
RANGE THERE.
FOR THE REMAINDER OF THE PERIOD...WESTERN HEIGHT FALLS AND EASTERN
RISES IN THE WAKE OF THE DEPARTING TROUGH WILL RESULT IN
ESTABLISHMENT OF FAST/QUASI-ZONAL FLOW ACROSS MUCH OF THE CONUS
THROUGH THE MIDDLE PART OF NEXT WEEK. MEANWHILE...THE AFOREMENTIONED
BAROCLINIC ZONE WILL BECOME QUASI-STATIONARY WITHIN THIS FLOW
PATTERN. IT IS THEREFORE NOT SURPRISING THAT GLOBAL MODEL DETAILS
DIVERGE DURING THIS TIME FRAME...AS THEY STRUGGLE TO RESOLVE WEAK
SHORT WAVES RIPPLING THROUGH THIS LOW AMPLITUDE PATTERN. THE GFS
OFFERS THE WETTER SOLUTION...WITH AT LEAST A COUPLE OF WEAK WAVES
SPREADING LIGHT PRECIP INTO THE REGION PRIOR TO THE ARRIVAL OF
ANOTHER FRONTAL SYSTEM LATE IN THE WEEK. THE ECMWF IS QUITE A BIT
DRIER. CONSIDERING THE PATTERN...IT PROBABLY BEHOOVES US TO MAINTAIN
AT LEAST A SLIGHT CHANCE POP DURING MOST PERIODS OF THE MEDIUM
RANGE...WITH THE HIGHEST POPS RESERVED FOR DAY 7 FOR THE POTENTIAL
APPROACH OF THE NEXT FRONTAL SYSTEM.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
AT KCLT...A SMALL CHANCE OF PRECIP EXISTS THIS AFTN...THOUGH TOO
SMALL TO MENTION. ANY PRECIP WOULD BE CONVECTIVE IN NATURE BUT
LATEST NAM/RAP SOUNDINGS ARE CAPPED IN THE MIDLEVELS...SO
PARTICULARLY DEEP CONVECTION OR THUNDER NOT EXPECTED. SWLY WINDS
WILL OCCASIONALLY GUST TO NEAR 20 KT. COLD FRONT WILL APPROACH FROM
THE NW TONIGHT...WITH WSHFT TO NW LIKELY 08-09Z. LLVL FORCING IN THE
PRESENCE OF ABUNDANT MOISTURE IS LIKELY TO BRING POPS AFTER MIDNIGHT
IF NOT SOONER. SOME ELEVATED INSTABILITY WILL STILL BE
PRESENT...HENCE PROB30 TSRA. IFR CANNOT BE RULED OUT IF A TSRA DOES
PASS OVER THE FIELD. CIGS ARE EXPECTED TO BOTTOM OUT AT LOW MVFR
INVOF THE FRONT...WITH POPS DIMINISHING AND CIGS GRADUALLY LIFTING
AFTER DAYBREAK.
ELSEWHERE...MAINLY VFR LEVEL CLOUDS WILL BE SEEN THIS AFTN WITH
SPOTTY CU AT MVFR LEVELS...THOUGH CIGS SHOULD REMAIN VFR. SMALL POPS
WILL CONTINUE THRU THE AFTN THOUGH TOO LOW TO MENTION. IN GENERAL
TRENDS OVERNIGHT WITH THE FROPA WILL BE SIMILAR TO KCLT...THOUGH THE
NWLY SHIFT WILL OCCUR AS EARLY AS 02-03Z AT KAVL AND OCCURRING AT
ALL SITES BEFORE DAWN. THUNDER CHANCES AHEAD OF THE FRONT EXIST
MAINLY AT THE UPSTATE SC SITES. GUIDANCE SPLIT ON FLT CATEGORY
OVERNIGHT BUT MVFR SEEMS MOST LIKELY GIVEN RELATIVELY LIGHT PRECIP
AND WINDS KEEPING THE BDY LAYER MIXED. KAND IS AN EXCEPTION WHERE
THE SIGNAL IS STRONGER FOR IFR. TSRA MIGHT PRODUCE BRIEF IFR
WHEREVER THEY OCCUR. IMPROVING CONDITIONS INTO MIDDAY FRI WITH
CONTINUED NWLY WINDS AND OCNL LOW END GUSTS.
OUTLOOK...SCATTERED SHOWERS MAY PRODUCE SOME RESTRICTIONS FRI AFTN.
HIGH PRESSURE WILL BUILD OVER THE REGION BEGINNING FRIDAY NIGHT
PRODUCING VFR CONDITIONS. A WEAK FRONT PASSING THRU SUNDAY NIGHT MAY
PRODUCE A FEW RESTRICTIONS BUT VFR SHOULD RETURN IN ITS WAKE.
CONFIDENCE TABLE...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT HIGH 88% HIGH 100% HIGH 82% HIGH 91%
KGSP HIGH 86% HIGH 100% HIGH 85% MED 62%
KAVL HIGH 98% HIGH 86% HIGH 83% HIGH 88%
KHKY HIGH 90% HIGH 94% MED 64% HIGH 90%
KGMU HIGH 89% HIGH 100% MED 76% MED 62%
KAND HIGH 86% HIGH 91% LOW 58% MED 68%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MINIMUM TEMPERATURES FOR MARCH 28TH...
GSP 26 1982
CLT 25 1982
AVL 11 1887
RECORD MINIMUM TEMPERATURES FOR MARCH 29TH...
GSP 26 1899
CLT 26 2013
AVL 19 1982
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...RWH
NEAR TERM...WIMBERLEY
SHORT TERM...LG
LONG TERM...JDL
AVIATION...WIMBERLEY
CLIMATE...LG
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1237 PM CDT THU MAR 26 2015
.AVIATION...
ANOTHER HOUR OR SO OF POST-FRONTAL MVFR CEILINGS...SCATTERING OUT
TO VFR BY 19-20Z. THE CURRENT ROBUST NORTHERLY WIND BEHIND THIS
MORNING`S COLD FRONTAL PASSAGE WILL GRADUALLY WEAKEN AROUND SUNSET
...REMAIN OFFSHORE AND VERY LIGHT THROUGH FRIDAY`S SUNRISE. AREAWIDE
SKC FROM EARLY THIS EVENING THROUGH THE REMINDER OF THIS TAF PERIOD.
31
&&
.PREV DISCUSSION... /ISSUED 1058 AM CDT THU MAR 26 2015/
DISCUSSION...
COLD FRONT AND ASSOCIATED SHOWERS AND THUNDERSTORMS ARE CURRENTLY
MOVING OFF THE COAST AND ACROSS THE COASTAL WATERS. WHILE THE
GREATEST CONCENTRATION IS OFF THE COAST...SOME LINGERING LIGHT/
MODERATE RAIN AREAS WILL HANG AROUND FOR ANOTHER HOUR OR SO.
THE FORECAST PACKAGE HAS THINGS COVERED...AND MIGHT UPDATE EVERYTHING
ONCE THE RAINS EXIT OUR AREA. 42
&&
PREV DISCUSSION... /ISSUED 401 AM CDT THU MAR 26 2015/
DISCUSSION...
AT 08Z SFC ANALYSIS SHOWS THE COLD FRONT STRETCHING FROM THE
ARKLATEX SW TO C TX AND NW HILL COUNTRY. A THIN LINE OF SHOWERS
HAS DEVELOPED ALONG AND JUST AHEAD OF THE FRONT. LLJ AT 850MB
STRETCHES FROM THE LOWER TX COAST NE THROUGH E TX AND TOWARDS THE
MISS RIVER VALLEY. WATER VAPOR AND 500MB ANALYSIS SHOW TROUGH AXIS
STRETCHING FROM THE N GREAT LAKES THROUGH THE PLAINS. POLAR JET
STRETCHES FROM THE S PLAINS NE TOWARDS THE GREAT LAKES WITH RIGHT
ENTRANCE REGION OVER OK MOVING EAST TOWARDS ARK. ANOTHER JET
STREAK WAS FOUND OVER THE N ROCKIES WHICH SHOULD FURTHER DEEPEN
THE TROUGH WITH UPPER LEVEL RIDGING OVER THE PAC COAST.
LATEST RAP/HRRR/3KM TXTECH WRF/4 KM WRF ARW ALL HAVE A PRETTY
GOOD HANDLE ON COLD FRONTAL PASSAGE ACROSS SE TX. LATEST 07Z HRRR
HAS INITIALIZED WELL AND BASED THE FIRST DAY FORECAST ON A BLEND
OF THESE TRENDS WITH THE RAP AND 3KM TX TECH WRF. FRONT SHOULD
REACH KCLL/KUTS 10-11Z...KIAH/KSGR/KHOU AROUND 13Z AND THEN OFF
THE COAST 15-16Z. MODELS DO SUPPORT CONVECTION INCREASING IN
COVERAGE MAINLY SOUTH OF HOUSTON AND ALONG THE COAST WHERE THE
FRONT INTERACTS WITH HIGHER MOISTURE. FORECAST WILL KEEP HIGHER
POPS FOR THE COASTAL AREAS AND OFFSHORE THROUGH 18Z. RAIN CHANCES
CLEAR OUT QUICKLY FROM 15-18Z INLAND. ANY THUNDERSTORM ACTIVITY
MAY BECOME STRONG BUT NOT LIKELY SEVERE DUE TO CAPPING AND LIMITED
INSTABILITY. THE 00Z CRP SOUNDING SHOWS A PRETTY GOOD CAP AT
800-750MB.
TEMP FORECAST WILL BE A CHALLENGE BECAUSE OF STRONG COLD
ADVECTION BEHIND THE FRONT. TEMPS ARE IN THE LOW/MID 60S THIS
MORNING AND MAY INCREASE A FEW DEGREES AHEAD OF THE FRONT MAINLY
ALONG THE COAST. TEMPS MAY DROP INTO THE 50S BEHIND THE FRONT BUT
AS CONVECTION/CLOUD COVER CLEARS...MAY GET SOME SLIGHT HEATING IN
THE AFTERNOON TO OFF SET COLD ADVECTION. SHORT RANGE MODELS KEEP
TEMPS IN THE 60S WHICH LOOKS REASONABLE.
FRI MORNING SHOULD BE A COOL START TO THE DAY WITH MIN TEMPS BACK
INTO THE 40S BUT MAX TEMPS SHOULD TOP OUT IN THE 70S. TEMPS
INCREASE OVER THE WEEKEND WITH WEAK UPPER LEVEL RIDGING OVER TX.
THE GFS/ECMWF DIVERGE IN THEIR SOLUTIONS OVER THE WEEKEND AND INTO
NEXT WEEK. WHILE THE MODELS THEMSELVES HAVE HAD RUN TO RUN
CONSISTENCY...THERE HAS NOT BEEN ANY CONSISTENCY WITH EACH OTHER.
THE PROBLEM SEEMS TO BE HOW EACH MODEL IS HANDLING A TROUGH THAT
PUSHES INTO THE PACIFIC COAST LATE FRI INTO SAT. THE ECMWF CUTS
OFF SOME VORTICITY FROM THIS TROUGH AND HAS IT RETROGRADE BACK
INTO THE PACIFIC WITH THE MAIN WAVE MOVING ACROSS THE PAC NW AND
INTO THE PLAINS BY SUNDAY. THE GFS DOES SIMILARLY WITH THE MAIN
WAVE BUT HAS A MORE COHERENT CLOSED OFF UPPER LOW OVER
CALIFORNIA/BAJA LATE SUNDAY. THIS SYSTEM THEN MOVES ACROSS THE S
ROCKIES INTO TX ON TUE. THE ECMWF HAS A MUCH WEAKER SYSTEM AND HAS
A STALLED FRONT ACROSS THE AREA. THIS MAKES THE FORECAST
CHALLENGING BECAUSE IF THE ECMWF VERIFIES THERE WILL BE LITTLE
WEATHER IMPACT. IF THE GFS IS CORRECT THEN THE TROUGH SWINGS OVER
SE TX WITH NEG TILT AND VERY FAVORABLE FOR HEAVY RAINFALL/SEVERE
WEATHER. FOR WHAT IT IS WORTH THE CANADIAN MODEL MIGHT BE A
COMPROMISE BETWEEN THE GFS/ECMWF BUT PERHAPS SUPPORTING THE ECMWF
A BIT MORE. FORECAST WILL KEEP 30/40 POPS AND MAX TEMPS WILL BE A
COUPLE DEGREES COOLER DUE TO POSSIBLE RAIN CHANCES AND CLOUD
COVER. THE SYSTEM CLEARS OUT EARLY NEXT WED WITH NO REAL CHANGE IN
AIRMASS. TEMPS NEXT WEEK COULD BE A GOOD 5-8 DEGREES ABOVE NORMAL. 39
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 45 74 51 78 54 / 0 0 0 0 0
HOUSTON (IAH) 49 75 54 79 56 / 0 0 0 0 0
GALVESTON (GLS) 54 70 60 73 63 / 0 0 0 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 1 AM CDT FRIDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE
FOLLOWING ZONES: MATAGORDA BAY.
SMALL CRAFT ADVISORY UNTIL 4 AM CDT FRIDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO
60 NM.
&&
$$
DISCUSSION...42
AVIATION/MARINE...31
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
405 PM EDT THU MAR 26 2015
.SYNOPSIS...
A STRONG COLD FRONT TO OUR WEST WILL TRAVEL EAST THIS EVENING AND
PUSH THROUGH THE AREA TONIGHT. MUCH COLDER AIR WILL BE MOVING IN
BEHIND THE COLD FRONT FOR THIS WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 400 PM EDT THURSDAY...
A STRONG COLD FRONT LOCATED JUST TO OUR WEST THIS AFTERNOON WITH
PREFRONTAL LINE OF CONVECTION AND ANAFRONT RAIN WELL BEHIND THE
FRONTAL BOUNDARY WILL MOVE EAST TONIGHT INTO FRIDAY. THE COLD AIR
WEDGE FINALLY ERODED THIS AFTERNOON WITH HEATING AND MIXING.
ANTICIPATING THAT ADDITIONAL CONVECTION WILL DEVELOP AHEAD AND ALONG
THE FRONT THIS AFTERNOON INTO TONIGHT AS IT MOVES EAST. SKINNY CAPE
AND INSTABILITY MAKES CONVECTION FORECAST PROBLEMATIC WITH THIS
BOUNDARY. USED A BLEND OF THE NAM AND HRRR FOR POPS THIS AFTERNOON
INTO TONIGHT. THERE IS SOME UNCERTAINTY IF CONVECTION DEVELOP EXACTLY
AS PROGGED ALONG BLUE RIDGE MOUNTAINS BY HIGHER RESOLUTION MODELS
LIKE THE RNKWRFARW...HRRR AND HIRESW-ARW. FOR THE WINDOW FOR
THUNDERSTORM DEVELOPMENT IS SMALL.
ANOTHER ISSUE IS WHETHER THE COLD AIR CATCHES FRONTAL MOISTURE
ASSOCIATED WITH THE FRONT SLOWED BY LOW PRESSURE WAVE MOVING ALONG
THE BOUNDARY LATE TONIGHT INTO FRIDAY. THE RATE OF FALL IS ALSO
IMPORTANT FOR LATE TONIGHT INTO FRIDAY MORNING FOR POTENTIAL COOLING
OF TEMPERATURES. BELIEVE THAT ENOUGH COLD AIR CATCHES SOME MOISTURE
LATE TONIGHT INTO FRIDAY TO CREATE SOME MOUNTAIN SNOW SHOWERS AND
SNOW FLURRIES. ANY SNOW ACCUMULATIONS WILL GENERALLY BE LIGHT AND
MAINLY IN THE WESTERN UPSLOPE FAVOR AREAS. THE STRONG COLD AIR
ADVECTION COMBINED WITH PRESSURE RISES OF 5 TO 10MB/6HRS WILL RESULT
IN GUSTY WINDS TONIGHT. LOW TEMPERATURES WILL DROP INTO THE MID 20S
IN THE NORTHWEST MOUNTAINS TO THE MID 40S IN THE PIEDMONT TONIGHT.
THE FRONTAL WAVES BEING DRIVEN BY UPPER LEVEL SHORT WAVE ENERGY WILL
KEEP RESIDUAL PRECIPITATION ACROSS THE EAST FRIDAY. MEANWHILE...
NORTHWEST WINDS WILL BE GENERATING UPSLOPE PRECIPITATION WEST OF THE
BLUE RIDGE AS MUCH COLDER COLDER AIR MOVES IN. SNOW ACCUMULATION IN
THE WESTERN MOUNTAINS WILL BE LIMITED BY THE STRENGTH OF THE SUN
THIS TIME OF YEAR AND WARM ANTECEDENT CONDITIONS. WPC IN DAY 1 PAINT
UP TO 2 INCHES POSSIBLE IN WESTERN GREENBRIER AND THE POTENTIAL UP
TO AN INCH IN THE WESTERN MOUNTAINS. HIGH TEMPERATURES FRIDAY WILL
RANGE FROM THE MID 30S IN THE NORTHWEST MOUNTAINS TO THE LOWER 50S
IN THE PIEDMONT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 340 PM EDT...
MAIN ISSUE FOR THE WEEKEND IS THE INFLUENCE OF THE DEEP UPPER TROUGH
AND ANOMALOUSLY COLD AIR MASS. FIRST...LINGERING LIGHT ACCUMULATING
SNOW SHOWERS ON WESTERN SLOPES OF APPALACHIANS FOR FRIDAY NIGHT AND
PERHAPS INTO FIRST PART OF SATURDAY ASSOCIATED WITH COLD ADVECTION
AND AIDED BY SOME SLIGHTLY DEEPER LIFT WHEN THE UPPER VORTICITY MAX
AND TROUGH AXIS SWING THROUGH BETWEEN MIDNIGHT AND DAYBREAK
SATURDAY. THEN WITH COLD AIR MASS IN PLACE...INCLUDING COLDER THAN
MINUS 10 C AT 850MB OVER MUCH OF THE AREA SATURDAY...HIGH TEMPS
SATURDAY WILL BE 15-20 F BELOW AVERAGE...AND WE COULD BE CLOSE TO
RECORD LOWS FOR SUNDAY MORNING THE 29TH...SEE CLIMATE SECTION BELOW.
WENT WITH COLDER MAV AND ECMWF GUIDANCE COMPARED TO MET...WHICH BOTH
KEEPING TRENDING DOWN...AND WAS TEMPTED TO GO EVEN COLDER THAN
GUIDANCE WITH THE URFACE HIGH RIGHT OVERHEAD SUNDAY MORNING. ONE
CAUTION IS THAT WARM ADVECTION ALOFT BEGINS AGAIN AND THERE COULD BE
SOME THIN CIRRUS DRIFTING AHEAD OF WARM FRONT...MOST LIKELY ACROSS
THE WEST...SO WILL WAIT ANOTHER 24 HRS BEFORE DECIDING TO GO BELOW
GUIDANCE OR NOT.
ALSO WITH UPPER TROUGH OVERHEAD AND SOME WEAK MID LEVEL
INSTABILITY...SOME MODELS SHOWING VERY LIGHT SHOWERS ACROSS CENTRAL
THROUGH FIRST HALF OF SATURDAY...SO INTRODUCED A SLIGHT CHC POP
THERE.
TEMPS SHOULD MODERATE NICELY DURNG THE DAY SUNDAY WITH RETURN OF
WARM ADVECTION...BUT STILL BELOW NORMAL. COULD SEE HAVING TO TWEAK
THOSE UP A FEW DEGREES BETWEEN NOW AND SUNDAY.
NEXT CLIPPER SYSTEM MAY ARRIVE AS EARLY AS SUNDAY NIGHT IN WEST BUT
THINK GFS IS A BIT TOO FAST WITH THIS GIVEN POSITION OF LARGER
TROUGH STILL OFF EAST COAST...SO LEANING TOWARD SLOWER ECMWF AND
HOLDING OFF ON BEST PRECIP CHANCES UNTIL MONDAY...BUT DO HAVE LOW
CHANCE FAR WEST BY AFTER MIDNIGHT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 355 PM EDT...
STILL SOME UNCERTAINTY IN TIMING OF THE CLIPPER SYSTEM AND AMOUNT OF
PRECIP GIVEN CURRENT MODEL DIFFERENCES...BUT ECMWF AND CANADIAN ON
SAME PAGE WITH MORE OF A DAYTIME MONDAY TIMING...AND ECMWF TRENDS
SHOWING LITTLE WETTER SOLUTION AND BETTER CHANCES FOR PRECIP TO
SPREAD INTO PIEDMONT AT SOME POINT...SO HAVE INCREASED POPS TO LOW
CHC FOOTHILLS AND SLIGHT CHC INTO ALL OF PIEDMONT...AND MAY
EVENTUALLY HAVE TO GO HIGHER IF TIMING HOLDS STEADY.
PLENTY MILD ENOUGH FOR ALL RAIN WITH THIS SYSTEM...WITH THE POSSIBLE
EXCEPTION OF HIGHEST TERRAIN IN WEST VIRGINIA MONDAY MORNING...BUT
DO NOT THINK THERE WILL BE ANY ISSUES WITH ACCUMULATING SNOW EVEN ON
HIGHEST RIDGES.
LARGE SCALE PATTERN KEEPS SOME CLIPPER ENERGY HEADING TOWARD THE
APPALACHIANS AGAIN FOR TUESDAY OR TUES NIGHT...BUT THIS COULD REMAIN
TO THE NORTH...WHICH IS WHAT CURRENT ECWMF SOLUTION SUGGESTS...AND
THERE IS A TREND TO FLATTEN THE PATTERN A BIT SO EVEN THE WETTER GFS
MAY NOT BRING US MUCH OF ANYTHING...AND WOULD MOST LIKELY DO SO ONLY
ON WESTERN SLOPES. AFTER THAT NEXT BEST CHANCE FOR PRECIP COMES BY
WED NIGHT INTO THURSDAY WITH BETTER FRONTAL PASSAGE AND TAP OF SOME
GULF MOISTURE AS MODELS SHOWING SOME ATTEMPT TO PHASE A SOUTHERN
SHORT WAVE WITH YET ANOTHER COMING OUT OF THE NORTHERN PLAINS. AT
THIS POINT...THINK THE GFS IS OVERDOING THE STRENGTH OF THE SOUTHERN
PIECE OF ENERGY GIVEN A LOT OF POTENTIALLY SPURIOUS CONVECTION NEAR
THE GULF COAST EARLIER WEDNESDAY...SO ONCE AGAIN WILL LEAN TOWARD
ECMWF WHICH IS SOMEWHAT DRIER AND NOT AS LIKELY TO SPREAD PRECIP
EAST. OBVIOUSLY WITH THIS BEING 6 TO 7 DAYS OUT...THERE IS MUCH
UNCERTAINTY WITH DETAILS...AND WITH WARMING TREND THROUGHOUT THE
WEEK TOWARD OR ABOVE AVERAGE TEMPERATURES ONCE AGAIN...THIS MID WEEK
SYSTEM SHOULD NOT POSE ANY PRECIP TYPE ISSUES...NOR DOES IT LOOK TO
HAVE MUCH CHANCE OF GENERATING ANY SEVERE WEATHER GIVEN EITHER A
WEAK WEDGE IN PLACE IF GOING MORE WITH GFS...OR A VERY LIMITED
MOISTURE TAP IF GOING MORE WITH ECMWF.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
AS OF 150 PM EDT THURSDAY...
VFR AND MVFR CEILINGS WILL LOWER THIS AFTERNOON INTO TONIGHT.
MIXING HAS ERODED THE COLD WEDGE IN MOST AREAS EXCEPT A NARROW
PATCH ALONG THE SOUTHERN BLUE RIDGE. WITH HEATING AND MIXING THIS
AFTERNOON...LIGHT WINDS WILL BECOME GUSTY OUT OF THE SOUTHWEST
THIS AFTERNOON.
HIGH CONFIDENCE THAT A STRONG COLD FRONT WILL CROSS THROUGH THE
REGION JUST AROUND 00Z/7PM AT KLWB AND KBLF. THE FRONT IS
EXPECTED TO REACH KLYH AROUND 04Z/MIDNIGHT AND KDAN AROUND
05Z/1AM.
SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP ALONG AND BEHIND
THE FRONT. VISIBILITY MAY DROP TO MVFR LEVELS IN THE HEAVIER RAIN
SHOWERS. WINDS WILL BECOME NORTHWEST BEHIND THE FRONT WITH GUSTS
AT 20 TO 30 KNOTS.
SHOWERS AND GUSTY WINDS WILL CONTINUE THROUGH FRIDAY AS MUCH
COLDER AIR SURGES INTO THE REGION. SNOW SHOWERS AND SNOW FLURRIES
ARE LIKELY WITH MVFR CEILINGS AND VISIBILITIES IN THE WESTERN
UPSLOPE AREAS OF THE MOUNTAINS LATE TONIGHT THROUGH FRIDAY NIGHT.
MEDIUM TO HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS
DURING THE TAF PERIOD.
WINDS WILL DIMINISH SATURDAY WITH VFR CONDITIONS AS HIGH PRESSURE
BUILDS INTO THE AREA. SCATTERED MVFR SHOWERS ARE POSSIBLE SUNDAY
NIGHT INTO MONDAY. VFR WEATHER IS EXPECTED TUESDAY.
&&
.CLIMATE...
RECORD LOWS FOR MARCH 29:
ROA19
BCB17
LYH23
DAN23
BLF19
LWB18
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...KK
NEAR TERM...KK
SHORT TERM...SK
LONG TERM...SK
AVIATION...AMS/KK
CLIMATE...SK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
402 PM EDT THU MAR 26 2015
.SYNOPSIS...
A STRONG COLD FRONT TO OUR WEST WILL TRAVEL EAST THIS EVENING AND
PUSH THROUGH THE AREA TONIGHT. MUCH COLDER AIR WILL BE MOVING IN
BEHIND THE COLD FRONT FOR THIS WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 400 PM EDT THURSDAY...
A STRONG COLD FRONT LOCATED JUST TO OUR WEST THIS AFTERNOON WITH
PREFRONTAL LINE OF CONVECTION AND ANAFRONT RAIN WELL BEHIND THE
FRONTAL BOUNDARY WILL MOVE EAST TONIGHT INTO FRIDAY. THE COLD AIR
WEDGE FINALLY ERODED THIS AFTERNOON WITH HEATING AND MIXING.
ANTICIPATING THAT ADDITIONAL CONVECTION WILL DEVELOP AHEAD AND ALONG
THE FRONT THIS AFTERNOON INTO TONIGHT AS IT MOVES EAST. SKINNY CAPE
AND INSTABILITY MAKES CONVECTION FORECAST PROBLEMATIC WITH THIS
BOUNDARY. USED A BLEND OF THE NAM AND HRRR FOR POPS THIS AFTERNOON
INTO TONIGHT. THERE IS SOME UNCERTAINTY IF CONVECTION DEVELOP EXACTLY
AS PROGGED ALONG BLUE RIDGE MOUNTAINS BY HIGHER RESOLUTION MODELS
LIKE THE RNKWRFARW...HRRR AND HIRESW-ARW. FOR THE WINDOW FOR
THUNDERSTORM DEVELOPMENT IS SMALL.
ANOTHER ISSUE IS WHETHER THE COLD AIR CATCHES FRONTAL MOISTURE
ASSOCIATED WITH THE FRONT SLOWED BY LOW PRESSURE WAVE MOVING ALONG
THE BOUNDARY LATE TONIGHT INTO FRIDAY. THE RATE OF FALL IS ALSO
IMPORTANT FOR LATE TONIGHT INTO FRIDAY MORNING FOR POTENTIAL COOLING
OF TEMPERATURES. BELIEVE THAT ENOUGH COLD AIR CATCHES SOME MOISTURE
LATE TONIGHT INTO FRIDAY TO CREATE SOME MOUNTAIN SNOW SHOWERS AND
SNOW FLURRIES. ANY SNOW ACCUMULATIONS WILL GENERALLY BE LIGHT AND
MAINLY IN THE WESTERN UPSLOPE FAVOR AREAS. THE STRONG COLD AIR
ADVECTION COMBINED WITH PRESSURE RISES OF 5 TO 10MB/6HRS WILL RESULT
IN GUSTY WINDS TONIGHT. LOW TEMPERATURES WILL DROP INTO THE MID 20S
IN THE NORTHWEST MOUNTAINS TO THE MID 40S IN THE PIEDMONT TONIGHT.
THE FRONTAL WAVES BEING DRIVEN BY UPPER LEVEL SHORT WAVE ENERGY WILL
KEEP RESIDUAL PRECIPITATION ACROSS THE EAST FRIDAY. MEANWHILE...
NORTHWEST WINDS WILL BE GENERATING UPSLOPE PRECIPITATION WEST OF THE
BLUE RIDGE AS MUCH COLDER COLDER AIR MOVES IN. SNOW ACCUMULATION IN
THE WESTERN MOUNTAINS WILL BE LIMITED BY THE STRENGTH OF THE SUN
THIS TIME OF YEAR AND WARM ANTECEDENT CONDITIONS. WPC IN DAY 1 PAINT
UP TO 2 INCHES POSSIBLE IN WESTERN GREENBRIER AND THE POTENTIAL UP
TO AN INCH IN THE WESTERN MOUNTAINS. HIGH TEMPERATURES FRIDAY WILL
RANGE FROM THE MID 30S IN THE NORTHWEST MOUNTAINS TO THE LOWER 50S
IN THE PIEDMONT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 340 PM EDT...
MAIN ISSUE FOR THE WEEKEND IS THE INFLUENCE OF THE DEEP UPPER TROUGH
AND ANOMALOUSLY COLD AIR MASS. FIRST...LINGERING LIGHT ACCUMULATING
SNOW SHOWERS ON WESTERN SLOPES OF APPALACHIANS FOR FRIDAY NIGHT AND
PERHAPS INTO FIRST PART OF SATURDAY ASSOCIATED WITH COLD ADVECTION
AND AIDED BY SOME SLIGHTLY DEEPER LIFT WHEN THE UPPER VORTICITY MAX
AND TROUGH AXIS SWING THROUGH BETWEEN MIDNIGHT AND DAYBREAK
SATURDAY. THEN WITH COLD AIR MASS IN PLACE...INCLUDING COLDER THAN
MINUS 10 C AT 850MB OVER MUCH OF THE AREA SATURDAY...HIGH TEMPS
SATURDAY WILL BE 15-20 F BELOW AVERAGE...AND WE COULD BE CLOSE TO
RECORD LOWS FOR SUNDAY MORNING THE 29TH...SEE CLIMATE SECTION BELOW.
WENT WITH COLDER MAV AND ECMWF GUIDANCE COMPARED TO MET...WHICH BOTH
KEEPING TRENDING DOWN...AND WAS TEMPTED TO GO EVEN COLDER THAN
GUIDANCE WITH THE URFACE HIGH RIGHT OVERHEAD SUNDAY MORNING. ONE
CAUTION IS THAT WARM ADVECTION ALOFT BEGINS AGAIN AND THERE COULD BE
SOME THIN CIRRUS DRIFTING AHEAD OF WARM FRONT...MOST LIKELY ACROSS
THE WEST...SO WILL WAIT ANOTHER 24 HRS BEFORE DECIDING TO GO BELOW
GUIDANCE OR NOT.
ALSO WITH UPPER TROUGH OVERHEAD AND SOME WEAK MID LEVEL
INSTABILITY...SOME MODELS SHOWING VERY LIGHT SHOWERS ACROSS CENTRAL
THROUGH FIRST HALF OF SATURDAY...SO INTRODUCED A SLIGHT CHC POP
THERE.
TEMPS SHOULD MODERATE NICELY DURNG THE DAY SUNDAY WITH RETURN OF
WARM ADVECTION...BUT STILL BELOW NORMAL. COULD SEE HAVING TO TWEAK
THOSE UP A FEW DEGREES BETWEEN NOW AND SUNDAY.
NEXT CLIPPER SYSTEM MAY ARRIVE AS EARLY AS SUNDAY NIGHT IN WEST BUT
THINK GFS IS A BIT TOO FAST WITH THIS GIVEN POSITION OF LARGER
TROUGH STILL OFF EAST COAST...SO LEANING TOWARD SLOWER ECMWF AND
HOLDING OFF ON BEST PRECIP CHANCES UNTIL MONDAY...BUT DO HAVE LOW
CHANCE FAR WEST BY AFTER MIDNIGHT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 355 PM EDT...
STILL SOME UNCERTAINTY IN TIMING OF THE CLIPPER SYSTEM AND AMOUNT OF
PRECIP GIVEN CURRENT MODEL DIFFERENCES...BUT ECMWF AND CANADIAN ON
SAME PAGE WITH MORE OF A DAYTIME MONDAY TIMING...AND ECMWF TRENDS
SHOWING LITTLE WETTER SOLUTION AND BETTER CHANCES FOR PRECIP TO
SPREAD INTO PIEDMONT AT SOME POINT...SO HAVE INCREASED POPS TO LOW
CHC FOOTHILLS AND SLIGHT CHC INTO ALL OF PIEDMONT...AND MAY
EVENTUALLY HAVE TO GO HIGHER IF TIMING HOLDS STEADY.
PLENTY MILD ENOUGH FOR ALL RAIN WITH THIS SYSTEM...WITH THE POSSIBLE
EXCEPTION OF HIGHEST TERRAIN IN WEST VIRGINIA MONDAY MORNING...BUT
DO NOT THINK THERE WILL BE ANY ISSUES WITH ACCUMULATING SNOW EVEN ON
HIGHEST RIDGES.
LARGE SCALE PATTERN KEEPS SOME CLIPPER ENERGY HEADING TOWARD THE
APPALACHIANS AGAIN FOR TUESDAY OR TUES NIGHT...BUT THIS COULD REMAIN
TO THE NORTH...WHICH IS WHAT CURRENT ECWMF SOLUTION SUGGESTS...AND
THERE IS A TREND TO FLATTEN THE PATTERN A BIT SO EVEN THE WETTER GFS
MAY NOT BRING US MUCH OF ANYTHING...AND WOULD MOST LIKELY DO SO ONLY
ON WESTERN SLOPES. AFTER THAT NEXT BEST CHANCE FOR PRECIP COMES BY
WED NIGHT INTO THURSDAY WITH BETTER FRONTAL PASSAGE AND TAP OF SOME
GULF MOISTURE AS MODELS SHOWING SOME ATTEMPT TO PHASE A SOUTHERN
SHORT WAVE WITH YET ANOTHER COMING OUT OF THE NORTHERN PLAINS. AT
THIS POINT...THINK THE GFS IS OVERDOING THE STRENGTH OF THE SOUTHERN
PIECE OF ENERGY GIVEN A LOT OF POTENTIALLY SPURIOUS CONVECTION NEAR
THE GULF COAST EARLIER WEDNESDAY...SO ONCE AGAIN WILL LEAN TOWARD
ECMWF WHICH IS SOMEWHAT DRIER AND NOT AS LIKELY TO SPREAD PRECIP
EAST. OBVIOUSLY WITH THIS BEING 6 TO 7 DAYS OUT...THERE IS MUCH
UNCERTAINTY WITH DETAILS...AND WITH WARMING TREND THROUGHOUT THE
WEEK TOWARD OR ABOVE AVERAGE TEMPERATURES ONCE AGAIN...THIS MID WEEK
SYSTEM SHOULD NOT POSE ANY PRECIP TYPE ISSUES...NOR DOES IT LOOK TO
HAVE MUCH CHANCE OF GENERATING ANY SEVERE WEATHER GIVEN EITHER A
WEAK WEDGE IN PLACE IF GOING MORE WITH GFS...OR A VERY LIMITED
MOISTURE TAP IF GOING MORE WITH ECMWF.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
AS OF 150 PM EDT THURSDAY...
VFR AND MVFR CEILINGS WILL LOWER THIS AFTERNOON INTO TONIGHT.
MIXING HAS ERODED THE COLD WEDGE IN MOST AREAS EXCEPT A NARROW
PATCH ALONG THE SOUTHERN BLUE RIDGE. WITH HEATING AND MIXING THIS
AFTERNOON...LIGHT WINDS WILL BECOME GUSTY OUT OF THE SOUTHWEST
THIS AFTERNOON.
HIGH CONFIDENCE THAT A STRONG COLD FRONT WILL CROSS THROUGH THE
REGION JUST AROUND 00Z/7PM AT KLWB AND KBLF. THE FRONT IS
EXPECTED TO REACH KLYH AROUND 04Z/MIDNIGHT AND KDAN AROUND
05Z/1AM.
SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP ALONG AND BEHIND
THE FRONT. VISIBILITY MAY DROP TO MVFR LEVELS IN THE HEAVIER RAIN
SHOWERS. WINDS WILL BECOME NORTHWEST BEHIND THE FRONT WITH GUSTS
AT 20 TO 30 KNOTS.
SHOWERS AND GUSTY WINDS WILL CONTINUE THROUGH FRIDAY AS MUCH
COLDER AIR SURGES INTO THE REGION. SNOW SHOWERS AND SNOW FLURRIES
ARE LIKELY WITH MVFR CEILINGS AND VISIBILITIES IN THE WESTERN
UPSLOPE AREAS OF THE MOUNTAINS LATE TONIGHT THROUGH FRIDAY NIGHT.
MEDIUM TO HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS
DURING THE TAF PERIOD.
WINDS WILL DIMINISH SATURDAY WITH VFR CONDITIONS AS HIGH PRESSURE
BUILDS INTO THE AREA. SCATTERED MVFR SHOWERS ARE POSSIBLE SUNDAY
NIGHT INTO MONDAY. VFR WEATHER IS EXPECTED TUESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...KK
NEAR TERM...KK
SHORT TERM...SK
LONG TERM...SK
AVIATION...AMS/KK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
151 PM EDT THU MAR 26 2015
.SYNOPSIS...
A STRONG COLD FRONT TO OUR WEST WILL TRAVEL EAST THIS AFTERNOON
AND PUSH THROUGH THE AREA TONIGHT. MUCH COLDER AIR WILL BE MOVING
IN BEHIND THE COLD FRONT FOR THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM EDT THURSDAY...
ADJUSTED TEMPERATURES AND RAISED HIGHS FOR THIS AFTERNOON.
MODIFIED POPS TO MATCH UP WITH RADAR AND MESOSCALE MODEL TRENDS.
MORE CHANGES THIS AFTERNOON.
AS OF 1007 AM EDT THURSDAY...
ADJUSTED CLOUD COVER THIS MORNING INTO THIS AFTERNOON TO BETTER
CAPTURE SUNSHINE NOTED ON THIS MORNINGS SATELLITE IMAGES. USED A
BLEND OF CANDIAN AND HRRR FOR CLOUD COVER INTO THE AFTERNOON.
MODIFIED TEMPERATURES FOR THIS MORNING WITH LATEST SFC OBS AND
MODEL TRENDS. LEANED TOWARDS THE WARM MOS FOR LATE MORNING WITH
THE SUNSHINE IN THE WEST. DECREASED POPS FOR THIS MORNING AND
ADJUSTED THEM TOWARDS A BLEND OF THE NAM AND HRRR INTO THIS
AFTERNOON. WITH MOST OF THE CONVECTION NOT RETURNING TO AFTER 21Z
THIS AFTERNOON. SCATTERED SHOWERS AND THUNDERSTORMS WILL ACCOMPANY
AND PRECEDE A COLD FRONT THIS AFTERNOON INTO TONIGHT. TIMING OF
FRONT LOOKS TO BE BETWEEN 23Z AND 05Z. THE CAPE LOOKED
MARGINAL/WEAK THIS AFTERNOON BECAUSE OF WARM LAYER AT 700 MB. AS
OF 13Z DAY ONE CONVECTION OUTLOOK STILL HAS OUR REGION IN THE
GENERAL THUNDERSTORM AREA WITH THE MRGL TO OUR EAST ALONG THE
COASTAL PLAINS OF VIRGINIA AND NORTH CAROLINA. MORE CHANGES LATER
THIS MORNING.
AS OF 430 AM EDT THURSDAY...
PERSISTENT WEDGE REMAINED IN PLACE EARLY THIS MORNING. BAND OF
SHOWERS AND ISOLATED THUNDERSTORMS TRACKING TOWARD DANVILLE AND
SOUTHEAST COUNTIES OF THE FORECAST AREA WILL BE ELEVATED OVER A
SHALLOW BUT STRONG INVERSION. JUST ABOVE THE INVERSION
LEVEL...STRATUS HAD FORMED IN ALL BUT THE FAR WESTERN COUNTY
WARNING AREA. HIGHER ELEVATIONS WERE IN THE CLOUDS WITH DRIZZLE
AND FOG REPORTED.
LATEST HRRR AND WRF RUNS HAD BEST PROBABILITY OF SHOWERS THIS
MORNING IN SOUTHEAST HALF OF THE FORECAST AREA...ESPECIALLY EAST
OF DANVILLE AND LYNCHBURG. BUFKIT SOUNDINGS SHOWED THE WEDGE
BREAKING IN MOST LOCATIONS BY NOON WITH THE STRATUS AND FOG
LIFTING AND WINDS COMING AROUND TO THE SOUTHWEST.
THIS AFTERNOON WHEN THE FORECAST AREA IS OUT OF THE WEDGE AND INTO
THE WARM SECTOR AHEAD OF THE FRONT EXPECTING ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL BE ABOUT 10
TO 15 DEGREES ABOVE NORMAL...BUT EVEN WITH THE WARMING...ONLY
MARGINAL CAPE IS EXPECTED DUE A WARM LAYER AROUND 700 MB THIS
AFTERNOON.
AT 4AM THE COLD FRONT EXTENDED FROM PITTSBURGH TO LITTLE ROCK. LOW
PRESSURE WILL MOVE ALONG THE BOUNDARY TONIGHT. A STRONG UPPER
TROF BEGINS TO DIG IN THE CENTRAL UNITED STATES TONIGHT. SHOWERS
WILL BE WIDESPREAD ALONG AND BEHIND THE FRONT. KEPT THE CHANCE OF
THUNDERSTORMS IN FOR THIS EVENING. 00Z LOCAL WRF WAS AN HOUR OF
TWO FASTER WITH THE FRONTAL PASSAGE THAN THE NAM AND GFS. AT THIS
TIME EXPECT THE FRONT TO REACH THE FAR WESTERN COUNTY WARNING AREA
AROUND 00Z/8PM AND EXIT THE EASTERN COUNTIES AROUND 05Z/1AM.
TEMPERATURES WILL DROP QUICKLY BEHIND THE FRONT TONIGHT. AIR MASS
WILL BE COLD ENOUGH TO SUPPORT SNOW IN THE HIGHEST ELEVATIONS WEST
OF THE BLUE RIDGE BY EARLY FRIDAY MORNING. THE STRONG COLD AIR
ADVECTION COMBINED WITH PRESSURE RISES OF 5 TO 10MB/6HRS WILL
RESULT IN GUSTY WINDS TONIGHT. BUFKIT SOUNDINGS SUGGESTED
OCCASIONAL GUST OF 25 TO 35 MPH.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
AS OF 345 AM EDT THURSDAY...
MODEL GENERATION OF WAVES ALONG THE COLD FRONT HAVE SLOWED ITS
PROJECTED PASSAGE ACROSS THE REGION. AND WHILE THE FRONT WILL BE
CLEAR OF US TO THE EAST BY FRIDAY...THE FRONTAL WAVES BEING DRIVEN
BY UPPER LEVEL SHORT WAVE ENERGY WILL KEEP RESIDUAL PRECIPITATION
ACROSS THE EAST FRIDAY MORNING. AT THE SAME TIME NORTHWEST WINDS
WILL BE GENERATING UPSLOPE PRECIPITATION WEST OF THE BLUE RIDGE AS
MUCH COLDER COLDER AIR MOVES IN. THE UPSLOPE PRECIPITATION WILL BE
RAIN FOR MOST LOCATIONS WEST OF THE RIDGE BUT THE HIGHER ELEVATIONS
OF THE FAR WESTERN SLOPES WILL SEE SNOW SHOWERS. GIVEN THE STRENGTH
OF THE SUN THIS TIME OF YEAR AND WARM ANTECEDENT CONDITIONS NO
ACCUMULATION IS EXPECTED DURING THE DAYTIME ON FRIDAY. BY FRIDAY
NIGHT THE HEART OF THE VERY COLD AIR WILL SURGE INTO THE
REGION...ALLOWING FOR UPSLOPE PRECIPITATION TO CHANGE TO SNOW FOR
ALL LOCATIONS WEST OF THE RIDGE. WITH NO SUN TO COMPETE WITH...SOME
ACCUMULATION IS POSSIBLE FRIDAY NIGHT MAINLY FOR THE FAR WESTERN
SLOPES WHERE AMOUNTS WILL GENERALLY BE AN INCH OR LESS. HIGH PRESSURE
WILL THEN BUILD IN FOR THE WEEKEND...BRINGING AN END TO THE SNOW
SHOWERS SATURDAY MORNING WITH FAIR WEATHER ON TAP THROUGH SUNDAY.
TEMPERATURES WILL BE RUNNING 10 TO 15 DEGREES BELOW NORMAL THROUGH
THE PERIOD WITH SATURDAY BEING THE COLDEST DAY OF THIS STRETCH. LOWS
SATURDAY MORNING WILL BOTTOM OUT GENERALLY IN THE TEENS WEST OF THE
RIDGE TO MIDDLE 20S EAST. WINDS WILL ALSO BE BLUSTERY AS THE COLDER
AIR MOVES IN FRIDAY AND FRIDAY NIGHT...PRODUCING WIND CHILL VALUES
SATURDAY MORNING OF ZERO TO 10 ABOVE WEST TO THE LOWER AND MIDDLE 20S
EAST. HIGHS SATURDAY WILL ONLY BE IN THE LOW TO MID 30S WEST AND IN
THE MID TO UPPER 40S EAST. THANKFULLY TEMPERATURES WILL START TO
REBOUND AS WE CLOSE OUT THE WEEKEND WITH THE COLD AREA OF HIGH
PRESSURE SINKING TO OUR SOUTHEAST...ALLOWING OUR WINDS TO COME
AROUND TO A SOUTHWESTERLY DIRECTION AND BRING WARMER AIR BACK INTO
THE REGION.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
AS OF 400 PM EDT WEDNESDAY...
NORTHWEST FLOW PREVAILS THROUGH MONDAY WITH AN ALBERTA CLIPPER
PROGGED TO TRACK ACROSS THE REGION SUNDAY NIGHT TO MONDAY. THE GFS
IS FASTER AND STRONGER WITH THIS SYSTEM THAN THE ECMWF...BUT GIVEN
THE PATTERN IN PLACE AT THAT POINT...THE GFS FORECAST SEEMS MORE
REASONABLE. POPS ARE QUESTIONABLE WITH THIS SYSTEM...SO HAVE JUST
INDICATED LOW CHC POPS IN THE WEST FOR NOW UNTIL BETTER CONSENSUS IS
OBTAINED FROM THE MODELS ON THIS SYSTEM. BEYOND THAT...THE UPPER
FLOW BECOMES MORE ZONAL AND THE FOCUS WILL BE ON A HIGHLY
KINEMATIC...PACIFIC BASED SYSTEM IN THE SOUTHERN STREAM EXPECTED TO
REACH THE CWA AT THE END OF THE FORECAST PERIOD. THIS COULD BE A
SEVERE WEATHER SYSTEM FOR THE SOUTHERN PLAINS TO THE SOUTHEAST
STATES...BUT MORE QUESTIONABLE FOR OUR AREA. YIELDED TOWARD THE
SUPERBLEND FOR POPS IN THE LAST TWO PERIODS TO BETTER AGREE WITH
NEIGHBORS. HOWEVER...TIMING OF THE ARRIVAL OF WARM ADVECTION
PRECIPITATION ASSOCIATED WITH THIS SYSTEM REMAINS HIGHLY
QUESTIONABLE AT THIS POINT. THE ZONAL FLOW WILL YIELD TO NEAR NORMAL
TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 150 PM EDT THURSDAY...
VFR AND MVFR CEILINGS WILL LOWER THIS AFTERNOON INTO TONIGHT.
MIXING HAS ERODED THE COLD WEDGE IN MOST AREAS EXCEPT A NARROW
PATCH ALONG THE SOUTHERN BLUE RIDGE. WITH HEATING AND MIXING THIS
AFTERNOON...LIGHT WINDS WILL BECOME GUSTY OUT OF THE SOUTHWEST
THIS AFTERNOON.
HIGH CONFIDENCE THAT A STRONG COLD FRONT WILL CROSS THROUGH THE
REGION JUST AROUND 00Z/7PM AT KLWB AND KBLF. THE FRONT IS
EXPECTED TO REACH KLYH AROUND 04Z/MIDNIGHT AND KDAN AROUND
05Z/1AM.
SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP ALONG AND BEHIND
THE FRONT. VISIBILITY MAY DROP TO MVFR LEVELS IN THE HEAVIER RAIN
SHOWERS. WINDS WILL BECOME NORTHWEST BEHIND THE FRONT WITH GUSTS
AT 20 TO 30 KNOTS.
SHOWERS AND GUSTY WINDS WILL CONTINUE THROUGH FRIDAY AS MUCH
COLDER AIR SURGES INTO THE REGION. SNOW SHOWERS AND SNOW FLURRIES
ARE LIKELY WITH MVFR CEILINGS AND VISIBILITIES IN THE WESTERN
UPSLOPE AREAS OF THE MOUNTAINS LATE TONIGHT THROUGH FRIDAY NIGHT.
MEDIUM TO HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS
DURING THE TAF PERIOD.
WINDS WILL DIMINISH SATURDAY WITH VFR CONDITIONS AS HIGH PRESSURE
BUILDS INTO THE AREA. SCATTERED MVFR SHOWERS ARE POSSIBLE SUNDAY
NIGHT INTO MONDAY. VFR WEATHER IS EXPECTED TUESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/KK
NEAR TERM...AMS/KK
SHORT TERM...MBS
LONG TERM...RAB
AVIATION...AMS/KK