Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/24/16
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
754 PM MDT WED MAR 23 2016
.UPDATE...
ISSUED AT 754 PM MDT WED MAR 23 2016
STRONG LOW WILL CONTINUE TO LIFT NORTHEAST OVER THE CENTRAL PLAINS
AND AWAY FROM COLORADO. SNOW AND WINDS WILL CONTINUE TO RAPIDLY
DECREASE THE REST OF THE EVENING ACROSS NORTHEAST COLORADO. EXPECT
SNOW TO END LATE THIS EVENING IN THE FAR NORTHEAST CORNER OF THE
STATE. LOOKS THERE WILL BE ENOUGH MOISTURE EMBEDDED IN THE
NORTHWEST FLOW BEHIND THE EXITING SYSTEM FOR SNOW SHOWERS OVER THE
MOUNTAINS TONIGHT AND THURSDAY. INCREASED POPS SOME FOR THIS.
ACCUMULATIONS WILL BE LIGHT...LESS THAN 2 INCHES.
LET ALL THE ADVISORIES AND WARNINGS EXPIRE EXCEPT FOR THE PLAINS
EAST OF A LINE FROM LIMON TO STERLING. THESE WARNING OVER FAR
EASTERN COLORADO ARE SET TO EXPIRE AT 10 PM. AS WINDS AND SNOW
DECREASE...CONDITIONS WILL CONTINUE TO IMPROVE THIS EVENING AND
PLAN ON EXPIRING THIS BLIZZARD WARNING AT 10 PM.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 243 PM MDT WED MAR 23 2016
VERTICALLY STACKED LOW NOW OVER NORTHWEST KANSAS WILL CONTINUE TO
MOVE EAST OF THE REGION. STRONG FORCING ON THE BACKSIDE OF THE LOW
WILL CONTINUE TO BRING HEAVY SNOW AND STRONG WINDS THE NORTHEAST
PLAINS THROUGH AROUND MID EVENING. ALONG THE FRONT RANGE...WINDS
ARE STARTING TO TURN WESTERLY IN AND NEAR THE FOOTHILLS AND SNOW
HAS STARTED TO DECREASE. EXPECT SNOW TO CONTINUE TO DECREASE AND
END LATE THIS AFTERNOON OR EARLY EVENING ALONG THE FRONT RANGE.
EXTENDED THE WARNINGS OVER THE PLAINS WHERE IT APPEARS SNOW AND
WINDS WILL CONTINUE INTO THE EVENING HOURS.
SNOW IS EXPECTED TO END ACROSS THE AREA BY MIDNIGHT...EXCEPT FOR A
FEW SNOW SHOWERS IN THE MOUNTAINS. COOLED TEMPERATURES FOR
THURSDAY DUE TO THE EXTENSIVE SNOW COVER. SNOW SHOWERS WILL
REMAIN POSSIBLE IN THE MOUNTAINS THURSDAY. ANY NEW SNOWFALL IS
EXPECTED TO BE LIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 319 AM MDT WED MAR 23 2016
DUE TO WEATHER AND COMPUTER ISSUES...VERY LITTLE TO NO CHANGES
WERE MADE. HERE IS THE PREVIOUS DISCUSSION FROM EARLIER THIS
MORNING.
A DISTURBANCE IN THE NW FLOW WILL PUSH IN FRIDAY TO INCREASE SNOW
FOR THE MOUNTAINS BY MORNING...THEN BRING A CHANCE FOR RAIN
SHOWERS OVER THE PLAINS IN THE AFTERNOON. TEMPERATURES SHOULD
WARM FURTHER ON FRIDAY BEFORE THE EXPECTED COLD FRONT PUSHES DOWN
THAT EVENING WITH UPSLOPE CONDITIONS EXPECTED OVER THE PLAINS.
LOOK FOR SNOW TO SPREAD ACROSS THE PLAINS WITH ACCUMULATING SNOW
EXPECTED THROUGH SATURDAY MORNING. THE SYSTEM ALOFT WILL LIKELY BE
AN OPEN WAVE...THOUGH LATEST GFS RUN SLOWS THE KEEPS IT DEEPER...
WITH MODERATE QG LIFT. AMOUNTS ARE HARD TO PINPOINT DOWN AT THIS
POINT...HOWEVER IT WILL BE LESS THAN WHAT IS EXPERIENCED TODAY.
LOCATIONS FAVORED IN UPSLOPE PATTERNS WILL SEE THE HIGHEST TOTALS.
SATURDAYS TEMPERATURES WILL AGAIN BE BACK INTO THE 30S TO LOW 40S
AT BEST.
UPPER RIDGING WILL THEN PUSH INTO THE AREA SUNDAY THEN
SOUTHWESTERLY FLOW ALOFT IS EXPECTED MONDAY AND TUESDAY AHEAD OF
THEN NEXT SYSTEM. LOOK FOR WARMER AND DRIER WEATHER FOR THESE
THREE DAYS...EXCEPT FOR A INCREASING MOISTURE PUSHING IN TUESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 754 PM MDT WED MAR 23 2016
SNOW HAS ENDED IN THE DENVER AREA. MID CLOUDS WILL SLOWLY DECREASE
THIS EVENING WITH CEILINGS OF 6000 TO 8000 FEET AT TIMES. EXPECT
CLOUDS TO SCATTERED AFTER MIDNIGHT. THERE WILL BE A SLIGHT CHANCE
FOR FOG LATE TONIGHT AND THURSDAY MORNING. THE HRRR SHOWS
VISIBILITY BELOW A QUARTER MILE. HOWEVER THE RAP AND GFS...KEEP
THE BOUNDARY LAYER TOO DRY FOR FOG. WILL LEAN TOWARDS NO FOG AT
THIS TIME DUE TO THE DRAINAGE WINDS MIXING THE DRIER AIR. WILL
HAVE VCFG IN THE TAF FOR A HEAD UP.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
BLIZZARD WARNING UNTIL 10 PM MDT THIS EVENING FOR COZ046-048>051.
&&
$$
UPDATE...MEIER
SHORT TERM...MEIER
LONG TERM...KRIEDERMAN
AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS ALBANY NY
200 AM EDT TUE MAR 22 2016
.SYNOPSIS...
WIDELY SCATTERED LAKE EFFECT SNOW SHOWERS WILL PERSIST FROM
INTERSTATE 90 NORTHWARD OVERNIGHT. OTHERWISE HIGH PRESSURE WILL
BUILD IN FOR MUCH OF TUESDAY. THEN...A FRONTAL BOUNDARY WILL WORK
WILL WORK ITS WAY SLOWLY SOUTH OUT OF CANADA BY TONIGHT. IT WILL
EVENTUALLY STALL OUT ACROSS OUR NORTHERN AREAS AND BECOME A
STATIONARY FRONT LATE TUESDAY NIGHT BRINGING UNSETTLED WEATHER FOR
MOST OF THE REGION THROUGH THE REST OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 200 AM EDT...RADARS STILL FOLLOWING QUASI LAKE EFFECT
SCATTERED SNOW SHOWERS PERSISTING NORTH OF INTERSTATE 90.
THE LATEST HRRR HAS A PARTIAL HANDLE BUT BELIEVE IT MIGHT
BE A TAD TOO FAST ENDING THE ACTIVITY.
IT MIGHT NOT END UNTIL THE H850 RIDGE REACHES...AFTER DAWN. WILL
CONTINUE ISOLATED SNOW SHOWERS THROUGH MUCH OF THE OVERNIGHT. NO
ADDITIONAL ACCUMULATIONS ARE EXPECTED EXPECT ACROSS THE ADIRONDACKS
WHERE A COUPLE TENTHS MORE OF SNOWFALL ARE POSSIBLE.
OUTSIDE THE SNOW SHOWER ACTIVITY...IT WAS MAINLY CLEAR. WE EXPECT
THIS TO CONTINUE. A GUSTY WIND STILL CONTINUED DOWN THE MOHAWK
VALLEY INTO THE CD AND HIGHER TERRAIN EAST OF THE HUDSON VALLEY. WE
EXPECT THESE WINDS TO ABATE BY DAWN...NOT COMPLETELY BUT DOWN TO 5-
10 MPH.
OVERNIGHT TEMPERATURES HAVE NOT BE FALLING MUCH DUE TO THE BREEZE AND SOME
CLOUDS. HOWEVER...WE THINK THEY WILL DROP SEVERAL DEGREES BY SUNRISE
AS THE BREEZE DIMINISHES. LOOK FOR LOWS IN THE UPPER 20S IN
THE CAPITAL REGION SOUTH THE THE MID HUDSON VALLEY...
UPPER TEENS TO MID 20S MOST OTHER PLACES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
A BAROCLINIC ZONE WILL BE SETTING UP ACROSS PORTIONS OF OUR AREA AS
WE GO INTO THE SHORT TERM FORECAST PERIOD ALONG A QUASI-STATIONARY
FRONT. THIS WILL SET UP THE CHANCES OF SOME WINTRY PRECIPITATION AS
WE GO INTO THE OVERNIGHT HOURS ON TUESDAY AND WEDNESDAY. 12Z MODEL
AND NUMERICAL DATA ARE NOT IN COMPLETE AGREEMENT AND WITH THE NATURE
OF THIS FRONTAL SYSTEM SETTING UP ACROSS PORTIONS OF THE
REGION...ANY SLIGHT CHANGE TO THE POSITION OF THE FRONT WILL CHANGE
THE P-TYPE FOR THIS SYSTEM WITH THE DIURNAL CYCLE.
TUESDAY THROUGH TUESDAY NIGHT...A SLOW MOVING COLD FRONT OUT OF
CANADA WILL WORK ITS WAY SOUTH THROUGHOUT THE DAY ON TUESDAY. SOME
OF THE LATEST 12Z MODEL AND PROBABILISTIC OUTPUTS ARE HINTING AT THE
COLD FRONT TO STALL OUT AND BECOME A STATIONARY FRONT OVER PORTION
OF NORTHERN NEW YORK AS WE GO INTO TUESDAY EVENING. THIS TEMPERATURE
DICHOTOMY ALONG THE STATIONARY FRONT WILL GENERATE A WEAK SURFACE
LOW PRESSURE SYSTEM MOVING EAST NORTHEAST ALONG THE BOUNDARY
STARTING LATE TUESDAY NIGHT. GIVEN THE DIURNAL TRENDS...ALONG AND
SOUTH OF THE STATIONARY BOUNDARY WILL PRODUCE JUST RAIN SHOWERS WHILE
NORTH OF THE BOUNDARY ACROSS THE ADIRONDACKS...SOME RAIN/SNOW IS
POSSIBLE AS TEMPERATURE TUESDAY NIGHT WILL BE NEAR FREEZING IN THE
ADIRONDACKS WITH SOME LIGHT ACCUMULATIONS POSSIBLE. HIGH
TEMPERATURES ON TUESDAY WILL RANGE FROM THE UPPER 30S TO MID AND
UPPER 40S WITH A FEW 50S IN PORTIONS OF THE MID HUDSON VALLEY. LOW
TEMPERATURES ON TUESDAY NIGHT WILL RANGE FROM LOWER 30S IN THE
ADIRONDACKS TO MID 30S TO LOWER 40S FOR THE REST OF THE REGION.
WEDNESDAY THROUGH WEDNESDAY NIGHT...LATEST 12Z MODEL SOLUTIONS BEGIN
TO SHOW SOME DISAGREEMENT AT THIS TIME...ESPECIALLY AS WE GO INTO
THE EVENING HOURS. SOME SOLUTIONS ARE SHOWING THE STALLED OUT FRONT
SLOWLY LIFT BACK NORTHWARD ALLOWING WARM AIR TO MOVE INTO THE MOST
OF THE REGION FROM SFC TO 850 HPA WITH A WESTERLY TO SOUTHWESTERLY
FLOW. OTHER SOLUTIONS ARE SHOWING THE FRONT STILL STATIONARY ACROSS
PORTIONS OF OUR NORTHERN AREAS. THIS SOLUTION IN PARTICULAR BY
WEDNESDAY EVENING WILL PROVIDE A TRICKY FORECAST FOR P-TYPES AS WE GO
INTO LATE WEDNESDAY NIGHT. AS WE GO INTO THE OVERNIGHT HOURS BY 2 AM
THURSDAY...SOME OF THE COLDER MODEL OUTPUTS HAVE 925 HPA
TEMPERATURES BELOW 0C BY 06Z THURSDAY FROM A LINE EXTENDING EAST
NORTHEASTWARD FROM CENTRAL HERKIMER COUNTY ACROSS THE NORTHERN
MOHAWK VALLEY...INTO SARATOGA COUNTY AND INTO SOUTHERN VERMONT. THIS
AXIS POINTS NORTHWARD MAY HAVE ENOUGH COLD AIR NEAR THE SURFACE FOR
SOME FREEZING RAIN POSSIBLE AS ANOTHER LOW PRESSURE IMPULSE RIDES
ALONG THE BAROCLINIC ZONE. IN OUR CURRENT FORECAST RIGHT
NOW...FREEZING RAIN IS MENTIONED FOR THE OVERNIGHT HOURS
WEDNESDAY INTO THURSDAY FOR THE LOCATIONS NORTH OF THE STALLED OUT
FRONT. WE WILL CONTINUE TO MONITOR THIS TRICKY TEMPERATURE FORECAST
AND WILL UPDATE THE PRECIPITATION TYPE FORECAST ACCORDINGLY. HIGH
TEMPERATURES WEDNESDAY WILL RANGE FROM THE UPPER 30S TO MID 40S
NORTH OF THE FRONTAL SYSTEM TO LOWER 50S TO LOWER 60S POSSIBLE SOUTH
OF THE FRONTAL BOUNDARY.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AN ACTIVE PATTERN TO START THE LONG TERM...WITH A ZONAL FLOW
TRANSITIONING INTO A SOMEWHAT HIGHER AMPLITUDE UPPER LEVEL PATTERN.
LINGERING UPPER LEVEL CONFLUENCE ACROSS EASTERN CANADA MAY SUPPORT
LOW LEVEL COOL AIR SETTLING SOUTH...AND OR PERSISTING ACROSS THE
REGION THURSDAY...BEFORE AN UPPER LEVEL IMPULSE EJECTING OUT OF THE
ROCKIES SHIFTS EAST. A SFC LOW ASSOCIATED WITH THIS FEATURE IS
EXPECTED TO DEEPEN AND TRACK INTO THE UPPER OHIO VALLEY OR EASTERN
GREAT LAKES FOR THU-FRI. A STRONG LOW LEVEL BAROCLINIC ZONE SHOULD
REMAIN ESTABLISHED FROM THE LOWER GREAT LAKES INTO THE INTERIOR
NORTHEAST DURING THIS TIME...SO SMALL DISPLACEMENTS ON THE FRONTAL
BOUNDARIES AND SFC LOW TRACK COULD MEAN WIDELY VARYING
TEMPERATURES...AND EVEN P-TYPES ACROSS THE REGION...ESP FOR NORTHERN
AREAS. OVERALL CONFIDENCE REMAINS LOW DUE TO THIS.
CURRENT THINKING IS THAT THE AFOREMENTIONED FRONTAL BOUNDARY SHOULD
REMAIN OVER THE REGION...OR JUST TO OUR S AND W ON THU. ON THE COOL
SIDE OF THE BOUNDARY...MAX TEMPS WILL LIKELY ONLY REACH THE 40S...IF
NOT COOLER. ON THE WARM SIDE...GENERALLY 50S-60S ARE EXPECTED...IF
NOT WARMER. HAVE SIDED A BIT COOLER THAN SUPERBLEND FOR THU
MAXES...WITH THE ASSUMPTION THAT THE BOUNDARY REMAINS TO OUR S AND W
FOR MOST OF THE DAY. EXPECT LOTS OF CLOUDS...AND AREAS OF LIGHT
RAIN/DRIZZLE. IN FACT...THERE COULD STILL BE SOME POCKETS OF
FREEZING RAIN ACROSS PORTIONS OF THE SOUTHERN ADIRONDACKS IN THE
MORNING. THEN...THE FRONT MAY LIFT NORTHWARD THU NT/EARLY FRI...JUST
AS THE SFC LOW AND COLD FRONT APPROACH FROM THE WEST/SOUTHWEST.
EXPECT RAIN AND/OR SHOWERS DURING THIS TIME. CAN NOT RULE OUT SOME
EMBEDDED THUNDERSTORMS...WITH SOME ELEVATED INSTABILITY. RAIN AND/OR
SHOWERS SHOULD TAPER OFF LATER FRIDAY. TEMPS THU NT/FRI AM SHOULD
REMAIN IN THE 30S/40S...WHILE MAX TEMPS FRI REACH THE 40S TO LOWER
50S.
FRI NT-SAT NT...WEAK HIGH PRESSURE MAY BUILD IN WITH FAIR WEATHER
AND TEMPS NEAR OR A BIT BELOW SEASONAL LEVELS...WITH MAXES IN THE
UPPER 40S/LOWER 50S IN VALLEYS...AND MAINLY 30S TO MID 40S FOR
HIGHER ELEVATIONS. OVERNIGHT MINS MAINLY IN THE 20S TO LOWER
30S...EXCEPT POSSIBLY SOME TEENS ACROSS THE SOUTHERN ADIRONDACKS.
SUN-MON...ANOTHER SYSTEM MAY APPROACH FROM THE WEST...ALTHOUGH THE
12Z/21 ECMWF REMAINS SLOWER WITH ITS OVERALL PROGRESSION. WILL
INDICATE INCREASING CLOUDS...WITH SLIGHT CHC POPS FOR SUN AFTERNOON
AND NIGHT INTO MONDAY. AGAIN...TEMPS SHOULD BE NEAR SEASONABLE
LEVELS...WITH HIGHS IN THE 50S TO NEAR 60 IN VALLEYS...AND UPPER 40S
TO LOWER 50S ACROSS HIGHER ELEVATIONS. OVERNIGHT MINS SHOULD FALL
INTO THE 30S...EXCEPT 20S ACROSS HIGHER TERRAIN. IF CLOUDS/RAIN
ARRIVE SOONER ON SUNDAY...MAX TEMPS COULD BE QUITE A BIT COOLER.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
HAVE PLACED A TEMPO FOR MVFR SNOW SHOWERS THROUGH 10Z AT KPSF AND
KALB AS THE SNOW SHOWER ACTIVITY HAS PERSISTED. OTHERWISE...VFR
CONDITIONS SHOULD PREVAIL THROUGH THE TAF PERIOD WHICH ENDS AT 06Z
WEDNESDAY.
THE GUSTY NORTHWEST WINDS AT KALB AND KALB SHOULD DIMINISH TO 5-
10KTS BY THE MORNING PEAK. THE WIND TURN MORE WESTERLY AND GUSTS TO
18KTS COULD RESUME MIDDAY AT KALB AND KPSF...BEFORE BACKING INTO THE
SW AND ULTIMATELY SOUTHERLY DIRECTION TONIGHT.
AN UPPER LEVEL DISTURBANCE WILL FINALLY LIFT OUT OVERNIGHT REPLACED
VERY BRIEFLY BY HIGH PRESSURE CRESTING TO OUR SOUTH. THEN...CLOUDS
FROM ANOTHER FRONT...DROPPING SOUTHWARD FROM CANADA...WILL MOVE IN
LATER TODAY...THICKEN AND COULD BRING SOME SHOWERS LATER TONIGHT
AFTER THE EVENING PEAK.
OUTLOOK...
WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
WEDNESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...RA.
THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
THURSDAY NIGHT: HIGH OPERATIONAL IMPACT. LIKELY SHRA.
FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
WIND GUSTS UP TO 30 MPH THIS AFTERNOON IN VALLEY LOCATIONS...
RH VALUES 20-25 PERCENT THIS AFTERNOON IN THE HUDSON VALLEY...
IT HAS BEEN MORE THAN FIVE DAYS SINCE SIGNIFICANT PRECIPITATION
(0.25 INCHES) HAS FALLEN ACROSS MOST OF EASTERN NEW YORK (EXCEPT FOR
HAMILTON/WARREN AND SARATOGA COUNTIES WHERE IT AS BEEN 3-5 DAYS
SINCE SIGNIFICANT PRECIPITATION HAS TAKEN PLACE). IT HAS BEEN 3-5
DAYS SINCE SIGNIFICANT PRECIPITATION HAS FALLEN ACROSS ADJACENT
WESTERN NEW ENGLAND.
LIGHT SNOW HAS FALLEN OVER LITCHFIELD COUNTY AND BERKSHIRE
COUNTIES...UP TO NEAR 3 INCHES IN PARTS OF WESTERN NEW ENGLAND THIS
MORNING.
WIDESPREAD PRECIPITATION IN THE FORECAST OVER THE NEXT COUPLE OF
DAYS WITH A STALLED OUT FRONTAL BOUNDARY WITH PRECIPITATION
ESPECIALLY ACROSS NORTHERN AREAS AND HIGH RH VALUES ACROSS ALL
AREAS.
&&
.HYDROLOGY...
NO HYDROLOGY PROBLEMS EXPECTED THROUGH EARLY IN THE WEEK.
A FRONTAL SYSTEM WILL STALL OUT ACROSS NORTHERN AREAS AS WE GO INTO
THE MIDDLE OF THE WEEK. WITH WEAK LOW PRESSURE IMPULSES MOVING
THROUGH THE REGION...LIGHT QPF AMOUNTS ARE EXPECTED. SOME
UNCERTAINTY REMAINS IN THE QPF FORECAST AND PRECIPITATION
TYPE...BUT THIS SHOULD NOT CAUSE ANY HYDROLOGIC ISSUES AT THIS TIME.
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...HWJIV/LFM
NEAR TERM...HWJIV/NAS
SHORT TERM...LFM
LONG TERM...KL
AVIATION...HWJIV
FIRE WEATHER...HWJIV/LFM
HYDROLOGY...HWJIV/LFM
&&
$$
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
743 PM EDT WED MAR 23 2016
.UPDATE...
23Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AND ACTIVE...BUT
PROGRESSIVE UPPER LEVEL PATTERN OVER THE CONUS THIS EVENING. MAIN
FEATURE CONSISTS OF A SHARP TROUGH/CLOSED LOW FEATURE EJECTING
EASTWARD AND CURRENTLY SPINNING OVER THE CENTRAL PLAINS. THIS
SYSTEM WILL BRING A WIDE VARIETY OF INCLEMENT WEATHER TO THE MID-
SECTION AND MID-WEST SECTION OF THE NATION THROUGH THE
OVERNIGHT...BUT WILL NOT PLAY A SIGNIFICANT ROLE IN OUR LOCAL
WEATHER UNTIL LATER THURSDAY AND INTO FRIDAY.
CURRENTLY WV IMAGERY SHOWS A BENIGN AND GENERALLY DRY WEATHER
PATTERN ALOFT OVER THE FLORIDA PENINSULA. OUR REGION RESIDES
BETWEEN THE NORTHERN STREAM FLOW ASSOCIATED WITH THE STORM IN THE
MID-SECTION OF THE COUNTRY...AND THE SOUTHERN STREAM FLOW OFF TO
OUR SOUTH. WITH LITTLE IN THE WAY OF SYNOPTIC SUPPORT FOR LIFT AND
LITTLE IN THE WAY OF COLUMN MOISTURE...OUR WEATHER STAYS QUIET AND
DRY THROUGH THE OVERNIGHT.
AT THE SURFACE...HIGH PRESSURE CONTINUES TO RIDGE BACK TO THE WEST
OVER THE PENINSULA FROM THE WESTERN ATLANTIC. THIS RIDGE HOLDS
POSITION THROUGH THE OVERNIGHT AND THEN WEAKENS THROUGH THE
DAYLIGHT HOURS OF THURSDAY IN RESPONSE TO THE SLOW APPROACH OF A
COLD FRONT FROM ACROSS THE GULF OF MEXICO.
FOR THE OVERNIGHT/THURSDAY MORNING...FEW-SCT SHALLOW CUMULUS
CLOUDS WILL GENERALLY DISSIPATE IN THE COMING HOURS WITH THE LOSS
OF DIURNAL HEATING...PROVIDING MOSTLY CLEAR SKIES TO START OUT THE
NIGHT. LOW TEMPERATURES BY DAWN WILL RANGE FROM THE LOWER/MID 50S
NORTH...TO THE LOWER AND MIDDLE 60S TO THE SOUTH OF THE I-4
CORRIDOR. AFTER MIDNIGHT...SYNOPTIC SETUP WILL BEGIN TO FAVOR AN
INCREASING WAA REGIME ABOVE THE SURFACE ARRIVING INTO SOUTHERN
FLORIDA FROM THE SOUTHWEST GULF/FLORIDA STRAITS. THIS PATTERN WILL
ONLY CONTINUE AND ADVANCE NORTHWARD INTO THURSDAY MORNING.
THEREFORE...EXPECT AN INCREASE IN CLOUDS LATER TONIGHT OVER THE
SOUTHERN ZONES THAT WILL EXPAND WITH TIME NORTHWARD INTO THE
DAYLIGHT HOURS OF THURSDAY. THE WAA AND LOW LEVEL ISENTROPIC
UPGLIDE OVER THE SOUTHERN HALF OF THE STATE IS ACTUALLY FAIRLY
DEFINED THE FIRST HALF OF THURSDAY...AND WOULD NOT BE SURPRISED TO
SEE MORE CLOUDS (AND EVEN A FEW SPRINKLES SOUTH OF I-4) EARLIER
THAN THE CURRENT FORECAST SHOWS.
THE SECOND HALF OF THURSDAY WILL RETURN RAIN CHANCES TO THE
FORECAST. WE ARE LOOKING AT A SITUATION WITH NO SINGLE STRONG
FORCING MECHANISM...BUT RATHER A SERIES OF WEAKER ONES COMBINING
TO DEVELOP SCT SHOWERS INTO THE AFTERNOON/EVENING HOURS. FIRST
MECHANISM WILL BE THE LOW LEVEL WAA/UPGLIDE REGIME OVER THE
STATE...HELPING TO MOISTEN THE BOTTOM OF THE TROP. SECOND...HIGH
ALOFT...THE SOUTHERN STREAM FLOW WILL BE SHIFTING NORTHWARD...WITH
A SERIES OF WEAK SHORTWAVE IMPULSES APPROACHING FROM THE
SOUTHWEST. THE WEAK PVA AND ASSOCIATED UPPER JET DYNAMICS WITH
THESE SHORTWAVES WILL AID THE OVERALL SYNOPTIC FORCING FOR
ASCENT. FINALLY...A LITTLE TERRESTRIAL DIURNAL HEATING THROUGH
THE DAYLIGHT HOURS WILL EVENTUALLY VEER THE WINDS NEAR THE COAST
TO THE SOUTH OR SOUTHWEST/ONSHORE...SETTING UP A LOW LEVEL
FOCUS/CONVERGENCE ZONE ACROSS THE REGION. ALL THESE FACTORS
SUGGEST A CHANCE FOR A SHOWER OR TWO JUST ABOUT ANY LOCATION
THURSDAY AFTERNOON. THE DEEPER INTO THE AFTERNOON/EARLY EVENING
WE GET...THE BETTER CHANCES FOR RAINFALL ARE LIKELY TO SHIFT
INLAND FROM THE I-75 CORRIDOR WITH THE DEEPER LAYER SOUTHWEST
FLOW. HOWEVER...AT LEAST SOME CONTINUING WEAK SYNOPTIC SUPPORT
FOR LIFT ALOFT SUGGESTS KEEPING A CHANCE FOR SHOWERS EVEN BACK TO
THE COAST ITSELF.
&&
.AVIATION...
VFR CONDITIONS BEING EXPERIENCED ACROSS ALL OF WEST-CENTRAL AND
SOUTHWEST FLORIDA WILL CONTINUE THROUGH THE OVERNIGHT HOURS.
CLOUDS WILL BE ON THE INCREASE THURSDAY MORNING WITHIN AN
INCREASING SOUTHEAST TO SOUTHERLY FLOW...HOWEVER CLOUD BASES
SHOULD REMAIN ABOVE VFR LIMITS. A SCATTERING OF SHOWERS ARE
EXPECTED TO DEVELOP ACROSS THE REGION AFTER MIDDAY THURSDAY. A
BRIEF PERIOD OF MVFR VIS/CIG WILL BE POSSIBLE WITH ANY PASSING
SHOWERS. OTHERWISE...VFR CONDITIONS PREVAIL THROUGH THE TAF
PERIOD.
&&
.MARINE...
HIGH PRESSURE CONTINUES TO RIDGE WEST OVER THE COASTAL
WATERS OVERNIGHT AND THEN WEAKENS WITH THE APPROACH OF A COLD
FRONT DURING THURSDAY AND THURSDAY NIGHT. THIS FRONTAL BOUNDARY
APPROACHES THE AREA FRIDAY...SHIFTING WINDS TO A MORE SOUTH
OR SOUTHWEST DIRECTION. THIS FRONT LOOKS TO STALL OUT OVER OR NEAR
THE REGION THROUGH THE WEEKEND...PROVIDING PERIODS OF WET WEATHER.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 64 81 70 81 / 0 30 50 50
FMY 64 85 70 86 / 0 20 40 40
GIF 61 85 69 85 / 0 50 50 60
SRQ 63 80 68 81 / 0 20 40 40
BKV 56 85 66 83 / 0 30 50 50
SPG 66 81 70 83 / 0 30 40 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE...14/MROCZKA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
949 PM CDT WED MAR 23 2016
.UPDATE...
949 PM CDT
MAIN CHANGES TO EVENING/OVERNIGHT FORECAST WAS TO TWEAK
TEMPERATURE AND WIND TRENDS BASED ON OBSERVATIONS OF QUASI-
STATIONARY FRONT POSITION...WHICH WAS LOCATED IN A MEANDERING
FASHION FROM JUST SOUTH OF PNT TO IKK TO SOUTH OF VPA TO JUST
NORTH OF OXI AS OF 0200 UTC. AS SURFACE LOW TRACKS NORTHEAST
OVERNIGHT INTO EARLY THURSDAY...PRESSURE FALLS WILL ENABLE FRONT
TO LIFT SLOWLY NORTH AS WARM FRONT TOWARD I-80 CORRIDOR...THOUGH
WILL MAKE BETTER NORTHWARD PROGRESS WITH EASTWARD EXTENT IN CWA.
STEEPER LAPSE RATES/COOLING ALOFT ASSOCIATED WITH IMPRESSIVE
CLOSED LOW ON W/V IMAGERY SHOULD ENABLE CAPPING IN PLACE TO
DIMINISH...WITH SLIGHT TO CHANCE THUNDER MENTION
MAINTAINED...BETTER CHANCE SOUTH OF THE FRONT. THERE HAS BEEN A
SLOW DOWNWARD TREND IN LIGHTNING COVERAGE OFF TO THE WEST.
THUS...REGARDING STRONG/SEVERE PROSPECTS OVERNIGHT/EARLY
THURSDAY...CANNOT COMPLETELY RULE IT OUT IN FAR SOUTHWEST
CWA. HOWEVER...IT APPEARS BETTER CHANCE FOR AN ISOLATED STRONG TO
SEVERE STORM WILL BE SOUTHWEST OF THE CWA WHERE SLIGHTLY HIGHER
INSTABILITY WILL RESIDE.
THERE HAS NOT BEEN MUCH IN WAY OF SIGNIFICANT VISIBILITY
REDUCTIONS THIS EVENING NORTH OF FRONT...BUT WITH LOW DEWPOINT
SPREADS MAINTAINED PATCHY FOG MENTION. BETTER POTENTIAL FOR AREAS
OF FOG...EVEN LOCALLY DENSE...COULD OCCUR JUST NORTH OF FRONT AND
CLOSER TO LAKE MICHIGAN IN PREDAWN HOURS THROUGH MID MORNING.
INCREASED FOG COVERAGE TO AREAS OF FOG IN GRIDS FOR THAT AREA.
FINALLY...REGARDING ACCUMULATING SNOW POTENTIAL ON THURSDAY
AFTERNOON...DID NOT MAKE BIG CHANGES TO GRIDS...BUT CONTINUE TO
BE CONCERNED FOR A PERIOD OF HEAVY SNOW RIGHT AFTER CHANGEOVER FOR
PARTS OF FAR NORTHERN ILLINOIS ALONG THE 700 MB DEFORMATION AXIS
PATH. ALONG WITH THE ROCKFORD AREA...THIS COULD INCLUDE NORTHERN
PORTIONS OF THE CHICAGO METRO AREA DURING THE AFTERNOON COMMUTE.
LATEST 00Z NAM IS ROUGHLY IN LINE WITH 18Z GFS IN THIS
SCENARIO...SO WILL NEED TO CLOSELY MONITOR OBSERVATIONAL TRENDS.
THINK THAT THE WINDOW WILL BE BRIEF AND PLACEMENT OF THE BAND
COULD VARY...BUT WITHIN IT...AMOUNTS OF 1"+ IN A SHORT TIME COULD
OCCUR/ESPECIALLY ON COLDER SURFACES. WILL BRIEF MIDNIGHT SHIFT ON
THESE CONCERNS.
RC
&&
.SHORT TERM...
331 PM CDT
THROUGH FRIDAY...
A SURFACE FRONTAL BOUNDARY REMAINS NEARLY STATIONARY OVER MY
SOUTHERN COUNTIES THIS AFTERNOON...WITH A SHARP CONTRAST IN
TEMPERATURES ON EITHER SIDE OF IT. TO THE NORTH...MAINLY 40S TO LOW
50S ARE PROMINENT...WITH THE EXCEPTION OF NEAR LAKE MICHIGAN WHERE
TEMPERATURES HAVE BEEN NEAR 40. SOUTH OF THE FRONT...TEMPERATURES
ARE IN THE LOW TO MID 60S. PRECIPITATION THROUGH THE DAY HAS BEEN
MAINLY TO OUR NORTH OF WISCONSIN...WHERE A BAND OF FRONTOGENESIS HAS
BEEN THE PRIMARILY DRIVER. HOWEVER...RADAR IMAGERY OVER THE PAST HOUR
HAS SHOWN AN UPTICK IN MAINLY VERY LIGHT RAIN OR DRIZZLE OVER
NORTHWESTERN ILLINOIS. THIS APPEARS TO BE THE MAIN STORY OVER THE
AREA THIS EVENING...WITH ONLY SOME LIGHT SHOWERS OR DRIZZLE
IMPACTING THE AREA.
SHOWERS...AND EVEN SOME THUNDERSTORM CHANCES SHOULD INCREASE FROM
WEST TO EAST OVER THE AREA OVERNIGHT INTO EARLY THURSDAY MORNING AS
THE MAIN STORM SYSTEM...NOW OVER THE KANSAS...SHIFTS TOWARDS
NORTHERN ILLINOIS. AS THIS LOW APPROACHES OVERNIGHT...THE SURFACE
FRONT WILL LIKELY SHIFT NORTHWARD UP NEAR THE I80 CORRIDOR BY
DAYBREAK THURSDAY. AS A RESULT...TEMPERATURES WILL LIKELY COME UP A
FEW DEGREES OVERNIGHT WHERE THE WARM FRONT PASSES. THE BEST CHANCE
OF THUNDERSTORMS LOOKS TO COME LATER TONIGHT INTO THURSDAY. THERE
ALSO CONTINUES TO BE A THREAT OF A FEW STRONG...TO POSSIBLY
MARGINALLY SEVERE STORMS OVER SOUTHERN PORTIONS OF THE AREA (MAINLY
SOUTH OF I-80) LATE TONIGHT THROUGH EARLY THURSDAY AFTERNOON.
OVERALL INSTABILITY WILL NOT BE OVERLY IMPRESSIVE...BUT THE
COMBINATION OF STRONG DEEP LAYER SHEAR AND THE DYNAMIC FORCING WITH
THE STORM SYSTEM COULD STILL SUPPORT A FEW STRONG STORMS AHEAD OF
THE COLD FRONT.
FARTHER TO THE NORTH...MAINLY OVER NORTHWESTERN AND PORTIONS OF FAR
NORTH CENTRAL ILLINOIS...THINGS COULD GET INTERESTING THURSDAY
AFTERNOON AS IT APPEARS A GOOD MID-LEVEL DEFORMATION ZONE MAY SET UP
OVER THIS AREA ALONG AND NEAR THE PATH OF THE 700 MB LOW. THIS COULD
SUPPORT A BAND OF MODERATE TO HEAVY WET SNOW OVER PORTIONS OF
NORTHWESTERN AND NORTH CENTRAL ILLINOIS...ESPECIALLY BY MID TO LATE
THURSDAY AFTERNOON. GIVEN THE POTENTIAL OF A BAND OF STRONG FGEN
SETTING UP WITHIN THIS DEFORMATION ZONE...ALONG WITH THE FACT THAT
LOOKS TO COINCIDE WITH THE PERIOD OF BEST MID-UPPER LEVEL Q-VECTOR
CONVERGENCE...ASSOCIATED WITH THE STRONG MID-LEVEL WAVE...THIS COULD
SET UP A PERIOD OF HEAVY SNOW. WE CAN ALSO NOT TOTALLY RULE OUT THE
POSSIBILITY OF CONVECTIVE SNOW RATES...ESPECIALLY CONSIDERING ALL OF
THE LIGHTNING AND REPORTS OF TSSN OVER WESTERN NEBRASKA OVER THE
PAST FEW HOURS. IN SPITE OF THIS POTENTIAL FOR SNOW...POSSIBLY
IMPACTING AREAS IN AND AROUND THE ROCKFORD AREA THURSDAY
AFTERNOON...UNCERTAINTY ON IMPACTS REMAIN LOW AT THIS TIME. THIS IS
DUE TO THE FACT THAT THESE BANDS OF HEAVY SNOW TEND TO BE
NARROW...AND GIVEN THAT GROUND TEMPS HAVE BEEN WARM LATELY IT WILL
TAKE HEAVY SNOW RATES IN ORDER TO GET ACCUMULATIONS...AND THIS MAY
END UP ONLY OCCURRING ON GRASSY AREAS AND ELEVATED SURFACES...WHERE
A COUPLE INCHES OF WET SNOW IS CERTAINLY POSSIBLE. THEREFORE...AT
THIS TIME I WILL MENTION THE POTENTIAL OF SOME HEAVY SNOW IN THE
HWO.
SOME SNOW COULD GET INTO THE CHICAGO AREA BY EARLY THURSDAY EVENING
BEFORE ENDING...BUT IT APPEARS UNLIKELY THAT ANY REAL ACCUMULATIONS
WOULD MATERIALIZE OUTSIDE OF NORTH CENTRAL ILLINOIS.
KJB
&&
.LONG TERM...
153 PM CDT
SATURDAY NIGHT THROUGH WEDNESDAY...
SATURDAY NIGHT THROUGH SUNDAY NIGHT...LOW PRESSURE CURRENTLY IN THE
GULF OF ALASKA WILL BE MOVING OUT OF THE SOUTHERN ROCKIES INTO THE
CENTRAL PLAINS ON SATURDAY NIGHT. A PORTION OF THE ENERGY WITH THIS
LOW WILL BE ABSORBED INTO THE NORTHERN STREAM UPPER LEVEL FLOW
PATTERN. THIS INTRODUCES CONSIDERABLE UNCERTAINTY INTO THE FORECAST
FOR SUNDAY INTO EARLY MONDAY AS FAR AS THE STRENGTH OF THE SURFACE
LOW THAT WILL DEVELOP...AND HOW PROGRESSIVE THE PATTERN WILL BE.
APPEARS THERE WILL BE SEMI-DECENT CHANCES FOR RAIN WITH THE LEAD
WAVE SATURDAY NIGHT...AND MODELS ARE IN PRETTY GOOD AGREEMENT ON
THIS. THE DIFFERENCES APPEAR MORE SO SUNDAY AS THE ECMWF IN ITS PAST
FEW RUNS DEVELOPS A STRONGER SURFACE LOW...AND THUS A MORE
SIGNIFICANT DEFORMATION BAND OF PRECIPITATION SUNDAY/SUNDAY NIGHT
WHEREAS THE GFS HAS A MORE PROGRESSIVE OPEN WAVE AND JUST SOME LIGHT
RAIN IF ANYTHING. THE GEM IS SOMEWHERE IN THE MIDDLE AND CLOSER TO
THE MORE FAVORED GUIDANCE FROM THE NATIONAL CENTERS...BUT ENSEMBLE
GUIDANCE STILL EXHIBITS QUITE A BIT OF SPREAD. THIS MIDDLE ROAD
SUGGESTS A DECENT BAND OF RAIN SUNDAY THEN SHIFTING EAST SUNDAY
NIGHT. WILL CONTINUE WITH THE MODEL BLEND WHICH GIVES HIGH END
CHANCE OF RAIN...WHICH COULD CERTAINLY BE HIGHER IF THE SLOWER
SOLUTIONS PREVAIL.
MONDAY... WEAK HIGH PRESSURE RETURNS FOR MONDAY RESULTING IN A
SEAONABLY COOL BUT DRY DAY WITH MORE SUNSHINE.
TUESDAY INTO MIDWEEK...ANOTHER DEEP UPPER TROUGH WILL BUILD ACROSS
THE WESTERN CONTINENTAL UNITED STATES. EXPECT SOME WARMING ON
TUESDAY CLOSER TO NORMS IN THE LOWER 50S...BUT WITH LOW PRESSURE
DEVELOPING TO OUR WEST ONSHORE WINDS WILL KEEP AREAS CLOSER TO THE
LAKE A BIT COLDER THAN NORMAL. THE UPPER LEVEL TROUGH WILL MOVE
EASTWARD INCREASING CHANCES FOR MILD AND WETTER WEATHER LATER IN THE
WEEK.
KMD
&&
.AVIATION...
FOR THE 00Z TAFS...
THE MEANDERING STATIONARY FRONT REMAINS JUST SOUTH OF THE TAF
SITES THIS EVENING WITH WINDS EXPECTED TO REMAIN NELY THROUGH THE
NIGHT AND MUCH OF TOMORROW MORNING. THE PERSISTENT FETCH OF COLD
AIR OFF OF LAKE MICHIGAN IS MOVING ONSHORE AND CIGS HAVE ALREADY
DROPPED TO IFR LEVELS. LATEST UGN METAR CARRYING 400FT CIG AND
LAKEFRONT WEBCAMS INDICATING LOW CIG/VIS CONDITIONS. LATEST MODEL
GUIDANCE SUGGESTING THE POSSIBILITY THAT CIGS COULD DROP TO
300FT...OR LESS...BUT CONFIDENCE IS NOT HIGH ENOUGH RIGHT NOW TO
CARRY CIGS LOWER THAN 400FT FOR NOW.
LATEST HIGH RES MODEL GUIDANCE SUGGESTING AN EARLIER TS
POTENTIAL...BEFORE 12Z...WITH A WEAK SFC LOW RIPPLING ALONG THE
FRONTAL BOUNDARY...JUST SOUTH OF THE CHICAGO AREA TERMINALS...ARND
11-13Z. THIS FEATURE COULD BE THE FOCUS THAT HELPS SOME TS
DEVELOPMENT IN THE CHICAGO AREA...BUT THE MAIN TS CONCERN WILL BE
IN THE WARMER AIR SOUTH OF THE FRONT.
THE MAIN SFC LOW SHOULD TRACK SOUTH AND EAST OF THE TERMINALS BY
EARLY TOMORROW AFTERNOON...WITH WINDS BACKING FROM NELY TO NWLY.
THERE SHOULD BE A SHORT PERIOD THERE WINDS WILL DROP OFF AND BECM
LESS GUSTY...BUT AS COLD AIR FILLS IN BEHIND THE EXITING
SYSTEM...WINDS WILL PICK UP AGAIN...GUSTING TO 25KT OR SO FOR THE
LATE AFTERNOON AND EARLY EVENING HOURS.
AREAS OF LIGHT RAIN OR DRIZZLE SHOULD PERSIST THROUGH THE NIGHT
AND MUCH OF THE DAY TOMORROW OUTSIDE OF SOME HEAVIER SHOWERS ARND
THE TIME OF GREATEST TS POTENTIAL. FOLLOWING THE PASSAGE OF THE
MAIN SFC LOW TOMORROW AFTERNOON...LIGHT RAIN SHOULD TRANSITION
OVER TO LIGHT SNOW IN THE EVENING BEFORE TAPERING OFF IN THE
EVENING AS LIGHT SNOW. RFD HAS THE GREATEST CHANCE FOR ANY
ACCUMULATING SNOW AS THAT SITE WILL BE CLOSER TO THE STRONGER
UPPER LEVEL FORCING THAN THE CHICAGO AREA TERMINALS.
KREIN
&&
.MARINE...
258 PM CDT
FRONTAL BOUNDARY DRAPED JUST SOUTH OF LAKE MICHIGAN WILL ALLOW FOR
CONTINUED BRISK NORTHEAST WINDS WHICH ALLOW FOR HIGHER WAVE ACTION
ON THE WEST HALF OF THE LAKE THROUGH TONIGHT. GALES
CONTINUE IN THE NORTHEAST REGIME FOR THE NORTHERN
MAJORITY OF THE LAKE TONIGHT. PRECIPITATION TRENDS
WILL BE ON THE INCREASE TONIGHT AS LOW PRESSURE NEARS FROM THE
SOUTHWEST. A SLIGHT INCREASE IN THE PRESSURE GRADIENT FOR THE
SOUTHERN THIRD OF THE LAKE WILL ALLOW WINDS TO INCREASE TO GALE
FORCE THURSDAY AFTERNOON. BY FRIDAY MORNING WINDS WILL RELAX AND
BECOME NORTHWEST...TRANSITIONING TO SOUTH AS HIGH PRESSURE NUDGES
IN.
MM
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ741 UNTIL 4 AM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...4 PM THURSDAY TO 4 AM FRIDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 PM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
National Weather Service Lincoln IL
908 PM CDT WED MAR 23 2016
.UPDATE...
Issued at 905 PM CDT Wed Mar 23 2016
The frontal boundary is extending across our northern counties,
has stalled out along a line from just south of Peoria to just
north of Bloomington. Steady northeast winds north of the front
are keeping cooler conditions there in the upper 40s, with
southerly winds south of the boundary keeping temps in the 60s.
Radar returns in east-central Illinois may be producing a few
sprinkles, but no measurable rain is expected from that band as it
mainly works to saturate the lower levels. Low pressure is still
expected to track east along the warm front, reaching near
Schuyler county around 15z/10am tomorrow. Then the low will
quickly track east across our northern counties and into Indiana
by 18z/1pm. The low will drag a cold front across our forecast
area in the process, with storms affecting our east-southeast
counties later Thursday morning into early afternoon, or mainly SE
of Effingham to Paris.
Instability params show some hail and wind potential with the
initial wave of storms that will reach Knox county around
05z/midnight, and clip northern Peoria county as well as Stark and
Marshall counties. Then the best instability looks to redevelop in
our E-SE counties Thur morning, but only marginal chances of
severe wind and hail are expected in that area as well.
Updates this evening were mainly to the weather grids to delay the
onset of rain and storms this evening, with better chances coming
after midnight. Temps are on track, with little change or diurnal
swings expected. Thus, a very mild night is in store south of the
front.
Updated forecast info is already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 258 PM CDT Wed Mar 23 2016
Frontal boundary position has not changed much since this morning,
with 2 pm analysis showing it extending from just north of Macomb,
to the northern Peoria metro area, to just south of Kankakee. Still
seeing temperatures only around 50 degrees at Galesburg, while the
Peoria airport (south side of metro) is 61 degrees. Further south,
mid-upper 60s were more widespread, with some 70 degree readings
toward Jacksonville. Radar mosaics show precipitation with this
system well off to our north.
The boundary extends southwest to a low pressure area in north
central Kansas. The low will slowly ride northeast along it, and
should nudge the front back north with time later tonight. HRRR
projecting convective development near the Missouri/Kansas border by
late afternoon, tracking it northeast to west central Illinois by
midnight. High-res models such as the ARW and NMM bring the line
into the central Illinois area after midnight. Best chances of any
strong/severe storms would basically be from I-55 west, where the
RAP model focuses MUCAPE values up to 1000 J/kg, but the incoming
line should get more disorganized with time so am not expecting a
widespread severe threat. Latest Day1 outlook has the entire
forecast area in a marginal risk of severe weather. More showers and
storms will surge northeast after midnight ahead of the incoming
cold front, with the highest PoP`s for eastern Illinois associated
with this surge.
Little in the way of temperature movement expected overnight, with
upper 50s to lower 60s prevailing much of the time. Biggest question
mark remains with the far north, depending on the position of the
front.
.LONG TERM...(Thursday through Wednesday)
ISSUED AT 258 PM CDT Wed Mar 23 2016
12Z forecast models generally bring 991 mb low pressure over
north central KS to track along a frontal boundary into northeast IL
by midday Thu as it weakens to 995-998 mb and swing a cold front
east across IL roughly between 15Z-21Z. High chances of showers and
a few thunderstorms early Thu morning to gradually diminish chances
from west to east during afternoon behind cold front. A new line of
convection to develop ahead of cold front during Thu afternoon and
SPC has marginal risk of severe near the Wabash river valley Thu
afternoon for hail and gusty winds, though best chances of stronger
storms will be further east of IN. Not much temp rise Thu with
breezy conditions again and may even slip behind the cold frontal
passage, with highs ranging from 50-55F nw of IL river to 60-65F
over eastern IL. Snow chances still appears to be north of CWA on
Thu and only have slight chances of light rain/snow showers Thu
evening over east central IL with no accumulations.
Low pressure moves into the eastern Great Lakes region overnight Thu
night and winds to gradually diminish as weak high pressure of 1020
mb settles east into the MS river valley by dawn Friday. Low clouds
to decrease from west to east overnight Thu night and set up another
night of freezing temps over central and nw IL. Lows 27-32F with
areas se of I-70 32-34F. Southern 6 counties where growing season
has begun, may need a freezing warning especially if clouds and
winds diminish quicker overnight Thu night. Weak high pressure
drifts east over IL Fri morning and into Ohio by sunset Friday,
providing a mostly sunny day with lighter winds, and highs mostly in
the lower 50s. So a similar day on Friday that we experienced this
past Monday.
A short wave trof off the Canadian Pacific coast will dive southeast
and deepen an upper level trof into the Rockies and great plains
this Easter Weekend. This ejects another fairly strong low pressure
ne from north Texas at sunset Saturday into central or southeast IL
on Easter Sunday. 12Z models still have some timing differences
along with placement of low pressure track and will stay close to
consensus. Have chances of showers into areas form I-55 west by
Saturday afternoon as clouds increase, with milder highs in the
upper 50s/lower 60s. Shower chances then spreading east over rest of
CWA Sat night, except still dry in far southeast IL near Wabash
river until Sunday. Depending on track of low pressure, southeast IL
may see a few thunderstorms on Easter Sunday. Highs Sunday range
from lower 50s nw of IL river, to 60-65F in southeast IL. Shower
chances to diminish from west to east overnight Sunday night and may
linger isolated showers near Wabash river Monday morning. High
pressure ridge already moving into IL by Monday afternoon to
decrease clouds on Monday with seasonable highs in the mid 50s.
Upper level ridging into the MS river valley on Tue and ohio river
valley next Wed to bring quiet weather with temps moderating to 55-
60F on Tue and into the 60s next Wed. Next chance of showers and
possible thunderstorms to arrive middle of next week on Wed night
and Thu as low pressure tracks into the upper MS river valley.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 700 PM CDT Wed Mar 23 2016
Frontal boundary has drifted south of PIA early this evening,
with winds shifting to the NE at PIA. The front is lingering just
north of BMI, where winds remain southerly. High-resolution
models show the front remaining nearly stationary early this
evening before pulling back north mid to late evening, as low
pressure approaches NW IL from the west. Gusty south winds south
of the front turn east-northeast on the other side of the
boundary. Have added a period of such a wind shift back to a
southerly wind direction at KPIA for late evening after the front
pushes back north. KBMI winds remain questionable, as the front is
very close to the north of them. Kept their winds southerly for
now, but will watch closely for a brief period of N-NE winds early
this evening. Aside from this front, general trend much of the
TAF period will be with gusty southerly winds, trending more
toward the southwest and eventually west-northwest late in the
period as a surface low passes across Illinois and into Indiana
Thursday afternoon.
Area of low VFR ceilings will prevail for this evening, then MVFR
clouds are expected to develop as showers and storms become more
numerous after midnight. HRRR and RAP output show a complex of
storms pass near PIA initially after midnight, then a larger
region of showers and storms for late tonight into Thursday
morning for the remainder of the TAF sites. Localized IFR
conditions could develop in cloud height and visibility during any
thunderstorms. Otherwise, MVFR clouds later tonight should
generally improve to VFR as the low passes east of the TAF sites,
and a dry slot brings an end to most of the precipitation later
Thur morning and Thur afternoon. An area of wrap-around moisture
could trigger afternoon showers for the northern TAF sites, but
little or no snow accumulation is expected for the I-74 corridor.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Shimon
SHORT TERM...Geelhart
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION...CORRECTED
NWS CHICAGO/ROMEOVILLE, IL
308 PM CDT TUE MAR 22 2016
.SHORT TERM...
221 PM CDT
THROUGH TONIGHT...
DESPITE CLOUDY SKIES...TEMPERATURES HAVE RISEN INTO THE 60S ACROSS
VIRTUALLY ALL OF THE REGION. GUSTY SOUTHWEST WINDS DIMINISH THIS
EVENING AND THE COLD FRONT OVER CENTRAL LAKE MICHIGAN SINKS SOUTH.
AT THE SAME TIME THE LOW CURRENTLY OVER COLORADO STRENGTHENS AND
MOVES OVER KANSAS.
THERE IS STILL A DECENT AMOUNT OF UNCERTAINTY REGARDING HOW FAR SOUTH
THE FRONT WILL SINK BY DAWN. THINKING THE FRONT WILL DIP INTO
NORTHERN IL AFTER MIDNIGHT AND BE AROUND THE I-88 CORRIDOR BY DAWN.
WHILE THE WHOLE AREA WILL BE CLOUDY OVERNIGHT...OTHER CONDITIONS
WILL VARY ALONG THE FRONT. AREAS NORTH OF THE FRONT WILL HAVE LOWS
IN THE LOW 40S TO THE UPPER 30S ALONG THE IL/WI STATE LINE ALONG
WITH NORTHEAST WINDS TO 15 MPH. WARMER AIR AND SOUTH WINDS WILL LIE
SOUTH OF THE FRONT...SO CONDITIONS MAY DIFFER FROM THE CURRENT
FORECAST DEPENDING ON WHERE THE FRONT ENDS UP.
FOR RAIN...FORECAST SOUNDINGS ALONG THE IL/WI STATE LINE FEATURE
SATURATION THROUGH THE FREEZING LEVEL AND A DECENT AMOUNT OF OMEGA.
HAVE HIGH CONFIDENCE IN RAIN/DRIZZLE NORTH OF THE FRONT/I-88
ESPECIALLY AFTER 4AM CDT. SOUNDINGS FURTHER SOUTH SATURATE THROUGH
THE EARLY MORNING HOURS WITH MINOR OMEGA VALUES SLOWLY INCREASING.
CAPPED POPS TO THE CHANCE RANGE SOUTH OF THE STATE LINE DUE TO A
LACK OF CONFIDENCE IN FORCING AND THE FRONTS LOCATION.
ALSO EXPECTING FOG TO FORM OVERNIGHT AS A SURFACE INVERSION FORMS.
GUIDANCE FEATURES FOG FORMING OVER THE SOUTHERN END OF THE LAKE AND
THINKING SOME OF THE FOG WILL MOVE OVER LAND WITH THE EAST WINDS.
THE DRIZZLE...RAIN...AND MOIST CONDITIONS SHOULD ALSO RESULT IN FOG.
NOT EXPECTING DENSE FOG AT THIS TIME.
JEE
&&
.LONG TERM...
234 PM CDT
WEDNESDAY THROUGH TUESDAY...
STRONG LAKE ENHANCED FRONT WILL LIKELY BISECT THE AREA WED
AFTERNOON...PROBABLY SETTING UP CLOSE TO I-80 AND LIKELY A BIT
FARTHER SOUTH THAN GUIDANCE SUGGESTS NEAR LAKE MICHIGAN. NORTH OF
THE FRONT BRISK EAST TO NORTHEAST WINDS OFF THE CHILLY LAKE WILL
RESULT IN A VERY STRONG AND SHALLOW INVERSION...BENEATH WHICH
MOISTURE SHOULD BE TRAPPED RESULTING IN A LOW OVERCAST. AS
DEWPOINTS SOUTH OF THE FRONT CLIMB INTO THE 40S TO LOWER 50S...THE
MARINE LAYER DISPLACING THAT MOIST AIR COULD RESULT IN LOCALLY
DENSE FOG OVER THE LAKE BLEEDING INLAND WEDNESDAY INTO WED NIGHT
NORTH OF THE FRONT. HIGHS TOMORROW NORTH OF THE FRONT SHOULD BE IN
THE 40S...THOUGH POSSIBLY HOLDING IN THE UPPER 30S NEAR THE NE IL
LAKEFRONT RANGING INTO THE 60S SOUTH OF THE FRONT.
GUIDANCE ALL HAS LIGHT PRECIPITATION NORTH OF THE BOUNDARY
WEDNESDAY...THOUGH FORECAST SOUNDINGS REALLY SUPPORT MORE OF A
DRIZZLE OR PERHAPS LIGHT RAIN WITH SIGNIFICANT DRY LAYER ABOVE THE
THICK STRATUS DECK. STEEP LAPSE RATES DO EXIST ABOVE THE FRONTAL
INVERSION...HOWEVER BETTER LARGE SCALE FORCING LOOKS TO SET UP TO
OUR NORTH OVER WI. SOUTH OF THE FRONT PRECIP CHANCES LOOK SMALL
AND HAVE LOWERED POPS SOME THOUGH PROBABLY NOT ENOUGH.
STRONG FRONT MAY TRY TO LIFT NORTH SOME WEDNESDAY NIGHT BATTLING
AGAINST THE COLD LAKE AS SURFACE LOW RIDES THE FRONT INTO NORTHERN
ILLINOIS. AGAIN SHOWERS WILL BE POSSIBLE IN THE WARM SECTOR WITH
FOG...LIGHT RAIN AND DRIZZLE NORTH OF THE BOUNDARY. SHOULD SEE AN
UPTICK IN PRECIP NORTH OF THE FRONT AS THE SHORTWAVE APPROACHES
THE REGION OVERNIGHT WITH SOME CHANCE OF A THUNDERSTORM WEDNESDAY
NIGHT OR PERHAPS EARLY THURSDAY MORNING.
STRONG AND GUSTY NORTHERLY WINDS WILL DEVELOP ON THE BACKSIDE OF
THE SYSTEM THURSDAY USHERING IN COLDER AIR TO AREAS THAT MADE IT
INTO THE WARM SECTOR...AND PROVIDING A CONTINUATION OF CHILLY
WEATHER ELSEWHERE. RAIN SHOULD GRADUALLY TAPER OFF LATER IN THE
AFTERNOON OR EVENING...POSSIBLY MIXING WITH OR CHANGING TO SOME
WET SNOW BEFORE ENDING. CANNOT COMPLETELY RULE OUT A BIT OF SLUSHY
ACCUMULATION ON GRASSY SURFACES...BUT CHANCES LOOK LOW AND KEPT
ACCUMS OUT OF THE GRIDS FOR NOW.
PROGRESSIVE PATTERN EXPECTED THROUGH THE PERIOD WITH NEXT SYSTEM
ALREADY RESULTING IN WARM AIR ADVECTION AND RETURN TO SOUTHERLY
FLOW FRIDAY. GFS AND ECMWF VARY IN THEIR HANDLING OF THE NEXT
TROUGH AND HOW MUCH SHORTWAVE ENERGY HANGS BACK IN THE BASE OF THE
TROUGH WITH FAIRLY SUBSTANTIAL DIFFERENCES BY EARLY NEXT WEEK
LEADING TO LOWER THAN AVG FORECAST CONFIDENCE. DOES APPEAR TO BE
SOME AGREEMENT IN THE BEST CHANCE OF SOME RAIN THIS WEEKEND BEING
IN SATURDAY NIGHT OR SUNDAY TIME FRAME. RAIN CHANCES WOULD
CONTINUE INTO NEXT WEEK IF ECMWF SOLUTION PANS OUT WITH GFS MORE
PROGRESSIVE AND MOVING THE TROUGH OUT QUICKER. GIVEN THE LOW
CONFIDENCE MAINTAINED THE CHANCE POPS FROM THE BLENDED MODEL
GUIDANCE.
IZZI
&&
.AVIATION...
FOR THE 18Z TAFS...
DRY...VFR...AND BREEZY THROUGH THE REST OF THIS AFTERNOON. WINDS
EASE EARLY THIS EVENING WITH CONTINUED VFR BKN SKIES. THE FRONT
CURRENTLY OVER CENTRAL LAKE MICHIGAN WILL CONTINUE TO SHIFT SOUTH
THROUGH THE NIGHT. THE FRONT SHOULD SETTLE JUST SOUTH OF MDW BUT
NORTH OF GYY WEDNESDAY MORNING AND STRETCH BOTH EAST AND WEST.
ONLY HAVE MEDIUM CONFIDENCE IN WHERE THE FRONT WILL STALL
WEDNESDAY. WINDS WILL BE NORTHEAST NORTH OF THE FRONT...SOUTH TO
SOUTHWEST SOUTH OF THE FRONT...AND THEN LIGHT ALONG THE FRONT.
RAIN AND DRIZZLE WILL SPREAD SOUTH WITH THE FRONT. THINKING THE
STEADIER RAIN WILL REMAIN NORTH OF THE FRONT WHILE AREAS ALONG AND
JUST SOUTH OF THE FRONT WILL SEE DRIZZLE VS STEADY RAIN. BOTH
AREAS SHOULD ALSO SEE AREAS OF FOG OF 2-3SM...PERHAPS LOWER.
THINKING THE LOWER VSBY WILL BE ALONG THE LAKE AS LAKE FOG SHOULD
FORM AND MOVE INLAND. THINKING RFD SHOULD HAVE SLIGHTLY HIGHER
VSBY DUE TO ITS DISTANCE FROM THE LAKE AND STRONGER WINDS.
OVERALL...VSBY CONFIDENCE IS HIGH IN MVFR OR LOWER VSBY...MEDIUM-
LOW THAT WHAT IS IN THE TAFS IS LOW ENOUGH. HAVE THE GREATEST
CONFIDENCE IN IFR OR LOWER CIGS ACROSS ALL OF THE TERMINALS.
JEE
&&
.MARINE...
234 PM CDT
FAIRLY ACTIVE PERIOD COMING UP ON THE LAKE. DEEPENING LOW OVER THE
PLAINS SHOULD RESULT IN STRENGTHENING EASTERLY FLOW OVER ALL BUT
FAR SOUTHERN TIP OF THE LAKE WEDNESDAY INTO WEDNESDAY NIGHT.
GUIDANCE SUGGESTS BETTER CHANCE OF GALES WILL HOLD OFF UNTIL
WEDNESDAY NIGHT NOW NORTHERN OPEN LAKE SO HAVE DELAYED START TIME
OF THE GALE WATCH A BIT. AS THE SYSTEM DEPARTS A PERIOD OF STRONG
COLD AIR ADVECTION AND TIGHT GRADIENT WOULD SUPPORT PERIOD OF
NORTHERLY GALES...PERHAPS HIGH END GALES THURSDAY INTO THURSDAY
NIGHT. HAVE EXPANDED THE GALE WATCH TO ENCOMPASS THE NEARSHORE
WATERS AS WELL AS THE OPEN LAKE.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 5 PM TUESDAY.
SMALL CRAFT ADVISORY...LMZ740...7 AM WEDNESDAY TO 4 AM THURSDAY.
GALE WATCH...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...1 PM THURSDAY TO 4 AM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO
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
307 PM CDT TUE MAR 22 2016
.SHORT TERM...(This evening through Wednesday)
ISSUED AT 307 PM CDT Tue Mar 22 2016
Earlier mid and high clouds over the northern CWA has been lifting a
bit northward this afternoon, but plenty more are advancing across
Missouri and will overspread central Illinois through early evening.
Wind gusts over 30 mph are becoming more common east of I-55 and the
highest gusts the last several hours have been from Bloomington to
Champaign, where they are now reaching 40 mph as of 2 pm. Over the
Wind Advisory area of southeast Illinois, the gusts have been a bit
slower to ramp up, but gusts to around 35 mph are more common. This
is below advisory criteria, but the RAP and HRRR suggest a bit more
increase the remainder of the afternoon, so will let the advisory
ride for now.
Latest surface map showing frontal boundary draped from northern
Lake Michigan into central Iowa and into the central Plains. While
the boundary will sag southward tonight, it is progged by all the
models to only reach about the I-80 corridor by sunrise, with most
of the models keeping any precipitation near or north of it. Have
maintained some 20% PoP`s late tonight north and west of Peoria, as
the GFS and RAP hint at a bit of development toward sunrise, but
general thought is that the night should largely remain dry. Few
changes made to low temperatures, with lower 50s prevailing over the
entire forecast area.
&&
.LONG TERM...(Wednesday night through Tuesday)
ISSUED AT 307 PM CDT Tue Mar 22 2016
One more breezy and unseasonably warm day is anticipated across
central and southeast Illinois on Wednesday. It will be dry for the
most part as well. The models have slowed a bit on the passage of an
approaching storm system, with the GFS slowing most considerably and
now close to matching the bulk of the other models. Have removed
thunderstorm mention from the daytime hours Wednesday. With the
slightly slower track of the system, the instability axis ahead of
the system`s cold front does not reach the forecast area until well
into the evening. Also, forecast soundings suggest strong capping in
place until just ahead of the front. Have maintained high PoPs
through most of Wednesday night, and kept thunderstorm chances in
place until FROPA (late Wednesday night into midday Thursday). The
precipitation associated with the system should pull east of the
area before temperatures fall far enough to support much in the way
of snow.
Cooler temperatures, but still near normal for late March, will
surge into the area to finish the week. The week should finish up
fairly quiet weather-wise as well, although a frontal system
approaching by late Saturday will bring rain chances back into the
area. While some spread still exists, model guidance is starting to
agree on a more progressive front, which would result in
precipitation chances pulling out by Sunday night. However, given
the lingering uncertainty/spread, left low PoPs in place into
Monday. If the progressive front suggested by the latest model runs
persists, Sunday night/Monday will end up dry.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1224 PM CDT Tue Mar 22 2016
Main concern in the short term will be with the winds. Gusts
currently ranging from 25-30 knots at the TAF sites, with a bit
higher speeds at times near KBMI/KCMI. Strongest winds expected
through about 00Z. Strong low level jet will keep the gusts
continuing much of the night from about KBMI-KDEC eastward, but
some settling of the wind is expected for a time further west. VFR
conditions to prevail during this time.
Looking further out, some MVFR ceilings will push southward
Wednesday morning from a frontal boundary that will be draped
over northern Illinois. Currently thinking KBMI and maybe KPIA
will be impacted by mid-late morning, but most of the area will
likely see them arrive around midday or a bit later. Gusty south
winds expected again Wednesday morning.
&&
.ILX Watches/Warnings/Advisories...
Wind Advisory until 7 PM CDT this evening for ILZ056-057-061>063-
066>068-071>073.
&&
$$
SHORT TERM...Geelhart
LONG TERM...BAK
AVIATION...Geelhart
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
1224 PM CDT TUE MAR 22 2016
.UPDATE...
Issued at 951 AM CDT Tue Mar 22 2016
Temperatures already reaching the lower 50s over parts of the
forecast area this morning, with southerly winds gusting over 30
mph. Latest HRRR guidance continues to suggest the highest winds
will be over the southeast CWA where the wind advisory is in
place. The grids generally had this trend on track, with little
change besides the usual hourly tweaks. However, significant
updates were done to the dew point grids, lowering them several
degrees. The impacts of this will be addressed in the Fire Weather
section below.
&&
.SHORT TERM...(Today)
ISSUED AT 325 AM CDT TUE MAR 22 2016
08z/3am surface analysis shows ridge of high pressure extending from
the eastern Great Lakes to the Gulf Coast, while a 1000mb low
develops over South Dakota. The pressure gradient between these two
features will continue to tighten today, resulting in strong
southerly winds. Forecast soundings suggest sustained winds of 15
to 20 mph across much of the area, with 20 to 25 mph winds focused
along/south of the I-70 corridor where gradient will be the
tightest. 08z Regional VAD wind profilers show 925mb winds of 55
to 60 mph and some of this momentum will mix to the surface once
the nocturnal inversion is broken between 15z and 18z. While
Bufkit momentum transfer shows gusts just shy of advisory criteria
across the SE KILX CWA, have decided to issue a Wind Advisory for
locations along/south of a Paris to Shelbyville line this
afternoon where gusts could reach 45 mph. Due to the strong
southerly flow and plenty of sunshine, high temperatures will soar
well into the 60s, with a few lower 70s from Springfield westward.
.LONG TERM...(Tonight through Monday)
ISSUED AT 325 AM CDT TUE MAR 22 2016
00z Mar 22 models have come into much better agreement concerning
the mid-week storm system, with the NAM/GEM/ECMWF all tracking low
pressure across north-central Illinois by 12z Thu. The GFS remains
about 6-12 hours faster and has been ignored due to its recent fast
bias. Large upper trough currently evident on latest water vapor
imagery along the West Coast will cross the Rockies and help the
Plains low deepen over northern Kansas by 12z Wed. The low will
then track E/NE into Illinois by Thursday morning. A baroclinic
zone extending eastward from the low will remain to the north of the
KILX CWA, generally along the I-80 corridor. As a result, all of
central and southeast Illinois will remain in the warm sector on
Wednesday. Due to only weak forcing and a lack of deep-layer
moisture, do not think there will be much precip on Wednesday. Have
carried just slight chance PoPs across most of the area, with chance
PoPs confined to the north in closer proximity to the front. As the
low approaches from the west, strengthening synoptic lift and
increasing moisture will lead to widespread showers and a few
thunderstorms Wednesday night Following the slower model consensus,
decided to linger likely PoPs through Thursday morning before
rapidly decreasing rain chances by afternoon. With the low exiting
the region, a few rain or snow showers may persist into Thursday
evening before ending overnight.
After that, cool/dry weather is expected for both Friday and
Saturday before unsettled conditions return early next week. Models
are in very poor agreement at this point, with the ECMWF and GEM
showing a progressive wave moving through the area on Sunday, while
the ECMWF is much more amplified with a slow-moving closed low that
could bring precip Saturday night through Monday night. With such a
high degree of model spread, did not make many changes beyond
Saturday...with low chance PoPs coming back into the picture for
both Sunday and Monday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1224 PM CDT Tue Mar 22 2016
Main concern in the short term will be with the winds. Gusts
currently ranging from 25-30 knots at the TAF sites, with a bit
higher speeds at times near KBMI/KCMI. Strongest winds expected
through about 00Z. Strong low level jet will keep the gusts
continuing much of the night from about KBMI-KDEC eastward, but
some settling of the wind is expected for a time further west. VFR
conditions to prevail during this time.
Looking further out, some MVFR ceilings will push southward
Wednesday morning from a frontal boundary that will be draped
over northern Illinois. Currently thinking KBMI and maybe KPIA
will be impacted by mid-late morning, but most of the area will
likely see them arrive around midday or a bit later. Gusty south
winds expected again Wednesday morning.
&&
.FIRE WEATHER...
Issued at 951 AM CDT Tue Mar 22 2016
Have lowered dew points by several degrees from the earlier grids.
Latest observations generally show lower-mid 30s over the area,
with the 30s dew points all the way upstream into southern
Oklahoma. Southeast half of the forecast area should see a fair
amount of mixing with the thicker high clouds covering the
northern half of the state, which would help the air stay drier.
With high temperatures forecast to reach the lower 70s over west
central Illinois and winds still progged to gust to around 30 mph
at times, relative humidity values expected to fall to around 30%
from Decatur- Lincoln westward. Red flag conditions will be
borderline during the midday and early afternoon in these areas.
&&
.ILX Watches/Warnings/Advisories...
Wind Advisory until 7 PM CDT this evening for ILZ056-057-061>063-
066>068-071>073.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Geelhart
FIRE WEATHER...Geelhart
AREA FORECAST DISCUSSION
National Weather Service Lincoln IL
951 AM CDT TUE MAR 22 2016
.UPDATE...
Issued at 951 AM CDT Tue Mar 22 2016
Temperatures already reaching the lower 50s over parts of the
forecast area this morning, with southerly winds gusting over 30
mph. Latest HRRR guidance continues to suggest the highest winds
will be over the southeast CWA where the wind advisory is in
place. The grids generally had this trend on track, with little
change besides the usual hourly tweaks. However, significant
updates were done to the dew point grids, lowering them several
degrees. The impacts of this will be addressed in the Fire Weather
section below.
&&
.SHORT TERM...(Today)
ISSUED AT 325 AM CDT TUE MAR 22 2016
08z/3am surface analysis shows ridge of high pressure extending from
the eastern Great Lakes to the Gulf Coast, while a 1000mb low
develops over South Dakota. The pressure gradient between these two
features will continue to tighten today, resulting in strong
southerly winds. Forecast soundings suggest sustained winds of 15
to 20 mph across much of the area, with 20 to 25 mph winds focused
along/south of the I-70 corridor where gradient will be the
tightest. 08z Regional VAD wind profilers show 925mb winds of 55
to 60 mph and some of this momentum will mix to the surface once
the nocturnal inversion is broken between 15z and 18z. While
Bufkit momentum transfer shows gusts just shy of advisory criteria
across the SE KILX CWA, have decided to issue a Wind Advisory for
locations along/south of a Paris to Shelbyville line this
afternoon where gusts could reach 45 mph. Due to the strong
southerly flow and plenty of sunshine, high temperatures will soar
well into the 60s, with a few lower 70s from Springfield westward.
.LONG TERM...(Tonight through Monday)
ISSUED AT 325 AM CDT TUE MAR 22 2016
00z Mar 22 models have come into much better agreement concerning
the mid-week storm system, with the NAM/GEM/ECMWF all tracking low
pressure across north-central Illinois by 12z Thu. The GFS remains
about 6-12 hours faster and has been ignored due to its recent fast
bias. Large upper trough currently evident on latest water vapor
imagery along the West Coast will cross the Rockies and help the
Plains low deepen over northern Kansas by 12z Wed. The low will
then track E/NE into Illinois by Thursday morning. A baroclinic
zone extending eastward from the low will remain to the north of the
KILX CWA, generally along the I-80 corridor. As a result, all of
central and southeast Illinois will remain in the warm sector on
Wednesday. Due to only weak forcing and a lack of deep-layer
moisture, do not think there will be much precip on Wednesday. Have
carried just slight chance PoPs across most of the area, with chance
PoPs confined to the north in closer proximity to the front. As the
low approaches from the west, strengthening synoptic lift and
increasing moisture will lead to widespread showers and a few
thunderstorms Wednesday night Following the slower model consensus,
decided to linger likely PoPs through Thursday morning before
rapidly decreasing rain chances by afternoon. With the low exiting
the region, a few rain or snow showers may persist into Thursday
evening before ending overnight.
After that, cool/dry weather is expected for both Friday and
Saturday before unsettled conditions return early next week. Models
are in very poor agreement at this point, with the ECMWF and GEM
showing a progressive wave moving through the area on Sunday, while
the ECMWF is much more amplified with a slow-moving closed low that
could bring precip Saturday night through Monday night. With such a
high degree of model spread, did not make many changes beyond
Saturday...with low chance PoPs coming back into the picture for
both Sunday and Monday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 610 AM CDT TUE MAR 22 2016
VFR conditions will prevail across the area through this forecast
period. The main forecast issue will be with the gusty south to
southwest winds today and another threat for non-convective LLWS
tonight. Mainly scattered to broken cirrus at around 20000 ft AGL
today with south to southwest winds of 20 to 25 kts with gusts
around 35 kts possible along and east of I-55 which would include
SPI, DEC, BMI and CMI. Forecast soundings and time height cross
sections indicate a decrease in wind speeds in the 1500 to 2000
foot layer this evening, with an increase in southwest flow at or
above 2500 feet later tonight into Wednesday morning. Borderline
LLWS at this point so will hold off including in this set of TAFs.
&&
.FIRE WEATHER...
Issued at 951 AM CDT Tue Mar 22 2016
Have lowered dew points by several degrees from the earlier grids.
Latest observations generally show lower-mid 30s over the area,
with the 30s dew points all the way upstream into southern
Oklahoma. Southeast half of the forecast area should see a fair
amount of mixing with the thicker high clouds covering the
northern half of the state, which would help the air stay drier.
With high temperatures forecast to reach the lower 70s over west
central Illinois and winds still progged to gust to around 30 mph
at times, relative humidity values expected to fall to around 30%
from Decatur- Lincoln westward. Red flag conditions will be
borderline during the midday and early afternoon in these areas.
&&
.ILX Watches/Warnings/Advisories...
Wind Advisory until 7 PM CDT this evening for ILZ056-057-061>063-
066>068-071>073.
&&
$$
UPDATE...Geelhart
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Smith
FIRE WEATHER...Geelhart
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
237 PM CDT TUE MAR 22 2016
...Updated Short term and Long term discussion...
.SHORT TERM...(THIS EVENING THROUGH Wednesday night)
ISSUED AT 234 PM CDT TUE MAR 22 2016
Tonight a cold front will remain nearly stationary along the
Nebraska border as a surface trough of low pressure/dryline moves
east across western Kansas. Lows tonight will be similar to last
night and range from the lower 40s in west central Kansas to the
lower 50s in south central Kansas.
On Wednesday an area of low pressure at the surface will deepen
as an upper low storm system lifts northeast from southern
Colorado into western Kansas early in the day. Given the
strengthening surface pressure gradient along with strong winds
aloft mixing down to the surface the winds across western Kansas
will be increasing into the 30 to 40 mph range by the early
afternoon. The strongest winds will occur during the mid to late
afternoon as a strong cold front crosses western Kansas. Behind
this cold front models suggest sustained winds of 35 to near 40
mph with gusts of around 55 mph. These speeds are just below High
Wind Warning criteria, but given the potential of these strong
winds being slightly stronger late Wednesday will issue a High
Wind Watch for Wednesday afternoon.
In addition to the strong winds falling afternoon temperatures
can be expected behind this cold front as clouds, cold air
advection and light precipitation develops. Initially this
precipitation will be in the form of rain but as temperatures fall
a mix of rain or snow will develop by late day/early evening in
north central Kansas. All snow will then develop early Wednesday
night across west central and north central Kansas with a period
of steady snow possible for a few hours. Snow accumulations of 1
to near 2 inches will be possible along and north of the I-70
corridor before the snow ends around midnight. Strong winds early
Wednesday evening will also create reduced visibilities due to
blowing snow.
Prior to the onset of precipitation the strong winds is expected
to produce a period of blowing dust Wednesday afternoon. Some
reduction in visibilities is expected due to this blowing dust.
.LONG TERM...(Thursday THROUGH Tuesday) ISSUED AT 234 PM CDT TUE
MAR 22 2016
On Thursday as the upper level storm system tracks northeast into
the Western Great Lakes Region a northwesterly flow will be
developing across the central Rockies. Northwest winds at 10 to 20
mph will back more to the west southwest during the day as a
surface ridge axis moves into central Kansas and a trough of low
pressure at the surface begins to develop[ along the lee of the
Rockies. 900mb to 850mb temperatures will begin to warm during the
day, mainly near the Colorado border. Given 900mb to 850mb
temperatures at 00z Friday the highs on Thursday are expected to
range from the low 50s in north central Kansas to the upper 50s in
far western Kansas.
900mb to 850mb temperatures will continue to warm on Friday ahead
of a cold front which will be dropping south out of Nebraska into
northern Kansas by late day. 850mb temperatures at 00z Saturday
continue to support highs in the mid 60s to lower 70s for western
Kansas. At this time will stay close to these temperatures for
highs despite the potential for increasing clouds from the west
late day ahead of the next approaching upper level trough.
Friday night into early Saturday a cold front will drop south
into the Texas panhandle as a northern branch upper level wave
crosses the Northern Plains. There may even be a chance for some
precipitation Friday night behind this front along a mid level
baroclinic zone that will be located across northern Kansas.
Saturday will be cloudy and cool. There may even be a slight
chance for some light precipitation during the day as moisture and
isentropic lift begins to develop ahead of an upper level trough
that will be crossing the four corners region. Given the cloud
cover and precipitation chances the highs may struggle to climb
much higher than the low to mid 50s.
From Saturday night through early Monday the latest global models
begin to diverge on the track and speed of this next upper level
trough as it moves from New Mexico into the the Central and
Southern Plains. Precipitation chances will improve late this
weekend, but exactly were the better chances for precipitation
will be is unclear. Will therefore stay close to the latest
CRExtendedFcst_Init for precipitation chances through Sunday
night.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Wednesday AFTERNOON)
ISSUED AT 1219 PM CDT TUE MAR 22 2016
12z NAM BUFR soundings along with the latest RAP and HRRR
indicating VFR conditions through early Wednesday. Mid level
clouds will be on the increase late Wednesday morning, however
cloud bases are expected to be at or above 12000 ft AGL. Gusty
southwest winds at 15 to near 20 knots this afternoon will
decrease to 10 to 15 knots after sunset. After 14z Wednesday a
westerly wind at DDC and GCK will increase into the 20 to 25 knot
range. Also given the strong winds developing just above the
boundary layer overnight have included a wind shear group at DDC
and GCK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 46 56 30 56 / 0 30 20 10
GCK 43 49 25 58 / 0 40 30 10
EHA 47 50 29 59 / 0 20 20 10
LBL 45 55 28 60 / 0 30 20 10
HYS 40 53 27 53 / 0 50 50 10
P28 48 68 32 58 / 0 10 10 10
&&
.DDC Watches/Warnings/Advisories...
Red Flag Warning until 9 PM CDT /8 PM MDT/ this evening for
KSZ030-031-043>046-061>066-074>081-084>090.
High Wind Watch from Wednesday afternoon through Wednesday
evening for KSZ030-031-043>046-061>066-074>081-084>090.
&&
$$
SHORT TERM...Burgert
LONG TERM...Burgert
AVIATION...Burgert
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
1223 PM CDT TUE MAR 22 2016
...Updated Synopsis and Aviation Discussion...
.SYNOPSIS...
ISSUED AT 1219 PM CDT TUE MAR 22 2016
At 12z Tuesday a 500mb trough was located over the Pacific
northwest. A 700mb and 500mb westerly flow was evident across the
central Rockies and the West Central High Plains. A surface
boundary extended from west to east across southern Nebraska and
the 850mb temperatures this morning ranged from +17C at North
Platte to +22C at Dodge City.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT TUE MAR 22 2016
Upper level ridging over the central High Plains this morning will
move off to the east today while a strong shortwave trough moves into
the Intermountain West. Increasing southwesterly flow aloft will
develop over western Kansas today ahead of the upper trough. At
the surface, a broad trough of low pressure will persist across
the central High Plains to the south of a low pressure system over
Nebraska. The low will redevelop westward today as the upper
system approaches. Across western and central Kansas, low level
flow will become southwesterly today as daytime heating increases. This
pattern will bring warm dry air into the area which should allow
temperatures to climb into the mid and upper 80s. Some locations
around Hays/Lacrosse could push 90 degrees.
By this evening, a cold front will be pushing into Nebraska while
the surface low begins to move eastward out of Colorado and along
the Kansas/Nebraska border. Southwesterly winds to the south of
the low should help keep low temperatures in the 40s to low 50s.
.LONG TERM...(Wednesday THROUGH Monday)
ISSUED AT 354 AM CDT TUE MAR 22 2016
By Wednesday morning, the upper level system will have closed off
into an upper low along the eastern Colorado/northwest Kansas
border. This system tracks east northeast into southeast Nebraska
by late Wednesday. The GFS continues to have the farthest north
track but the GEM model is fairly similar. The ECMWF has been
showing a farther south track for the past few runs but seems to
be trending a little farther north with this evenings run. In the
wake of the system a strong cold front will push southeast across
western and central Kansas Wednesday afternoon.
A fairly strong pressure gradient is progged to develop along with
850 millibar winds pushing 50 knots. We could be looking high wind
criteria conditions during the afternoon and early evening hours
before the gradient relaxes. After collaboration with adjacent offices,
the consensus is to hold off on any headlines for now but have
increased the winds in the forecast and will be highlighting the
threat a little harder in the Hazardous Weather Outlook.
Chances for light rain will be increasing across west central
Kansas by early afternoon and spreading east and southeast through
the remainder of the afternoon and early evening behind the front.
The best chances remain up along the Highway 96 and I-70 corridors,
closer to the track of the upper low. Model soundings show that
the lower levels remain warm enough through the afternoon hours
that precipitation should remain liquid. By Wednesday evening,
there should be enough cold air filtering into the area to bring a
mix with or change over to light snow. It appears that any accumulations
will generally be less than an inch as the upper low will be moving
away from the region during the evening hours. Precipitation
chances will be coming to an end by midnight and winds will also
be diminishing.
In the wake of the Wednesday system, upper level flow will become
more zonal with time albeit with lower heights and thickness
values. We will see fairly quiet weather through Friday with highs
in the 50s and 60s before another upper level disturbance and
attendant cold front push through the central Plains Friday night
and Saturday. This system will bring another chance for
precipitation to the region but there is more uncertainty among
the models as to how good of chances there will be as well as
precipitation type.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Wednesday AFTERNOON)
ISSUED AT 1219 PM CDT TUE MAR 22 2016
12z NAM BUFR soundings along with the latest RAP and HRRR
indicating VFR conditions through early Wednesday. Mid level
clouds will be on the increase late Wednesday morning, however
cloud bases are expected to be at or above 12000 ft AGL. Gusty
southwest winds at 15 to near 20 knots this afternoon will
decrease to 10 to 15 knots after sunset. After 14z Wednesday a
westerly wind at DDC and GCK will increase into the 20 to 25 knot
range. Also given the strong winds developing just above the
boundary layer overnight have included a wind shear group at DDC
and GCK.
&&
.FIRE WEATHER...
ISSUED AT 354 AM CDT TUE MAR 22 2016
Southwest winds will increase and become gusty across all of
southwest into central and south central Kansas this afternoon.
The resulting warm and dry airmass will result in relative
humidity values dropping into the single digits and lower teens.
The combination of this and the gusty winds will result in extreme
fire weather conditions. A Red Flag Warning is in effect for the
entire area this afternoon and early evening.
Elevated fire weather conditions could develop in the area around
Coldwater, Pratt and Medicine Lodge on Wednesday before a cold
front pushes through in the afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 87 46 56 30 / 0 0 20 20
GCK 85 43 49 25 / 0 0 40 30
EHA 85 47 50 29 / 0 0 30 20
LBL 86 45 55 28 / 0 0 20 20
HYS 88 40 53 27 / 0 0 50 50
P28 87 48 65 32 / 0 0 0 10
&&
.DDC Watches/Warnings/Advisories...
Red Flag Warning until 9 PM CDT /8 PM MDT/ this evening for
KSZ030-031-043>046-061>066-074>081-084>090.
&&
$$
SYNOPSIS...Burgert
SHORT TERM...Gerard
LONG TERM...Gerard
AVIATION...Burgert
FIRE WEATHER...Gerard
AREA FORECAST DISCUSSION
NWS JACKSON KY
808 PM EDT WED MAR 23 2016
.UPDATE...
ISSUED AT 808 PM EDT WED MAR 23 2016
SOUTH TO SOUTHWEST WINDS CONTINUE TO DECREASE THIS EVENING...WITH
SUSTAINED SPEEDS OF GENERALLY 5-10 MPH AND GUSTS UP TO 15-20 MPH
AT TIMES. TEMPERATURES WILL STEADILY FALL THROUGH THE 60S AND INTO
THE 50S OVER THE NEXT FEW HOURS WHILE DEWPOINTS INCREASE OWING TO
AN INFLUX OF MOISTURE FROM THE SOUTHWEST.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 419 PM EDT WED MAR 23 2016
WE CONTINUE IN THE SAME REGIME AS THE LAST COUPLE OF DAYS...BEING
IN BETWEEN HIGH PRESSURE TO THE EAST AND STRONG LOW PRESSURE TO
THE WEST. THE PRESSURE GRADIENT RESULTED IN GUSTY WINDS
AGAIN...ESPECIALLY IN THE WESTERN PORTION OF THE FORECAST AREA.
DEW POINTS FINALLY STARTED TO MAKE A MORE SUBSTANTIAL CLIMB IN OUR
WESTERN COUNTIES TODAY. HOWEVER...IT REMAINED DRY IN OUR EASTERN
COUNTIES...WITH RH AGAIN FALLING BELOW 25 PERCENT IN MANY
LOCATIONS.
THE LOW OVER THE MIDDLE OF THE CONUS WILL FINALLY ACCELERATE TO
THE EAST TONIGHT...AND PASS OVER THE GREAT LAKES LATE THURSDAY AND
THURSDAY NIGHT. AS ITS TRAILING COLD FRONT APPROACHES...GULF OF
MEXICO MOISTURE WILL CONTINUE TO MAKE A COMEBACK. MOISTURE WILL BE
SUFFICIENT FOR PRECIP TO OCCUR ALONG AND AHEAD OF THE FRONT AS THE
ASSOCIATED UPPER TROUGH LENDS SUPPORT...WITH THE MOST LIKELY TIME
BEING LATE THURSDAY INTO THURSDAY EVENING. FORECAST SOUNDINGS
CONTINUE TO SHOW WEAK INSTABILITY AND STRONG WIND FIELDS.
THUNDERSTORMS ARE STILL A POSSIBILITY...AND COULD BRING STRONG
WINDS.
COLDER AIR ARRIVES BEHIND THE FRONT ON THURSDAY NIGHT...AND MOST
IF NOT ALL PRECIP WILL COME TO AN END AS SURFACE HIGH PRESSURE
STARTS TO BUILDS IN FROM THE WEST LATE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 310 PM EDT WED MAR 23 2016
THE EXTENDED PERIOD OF THE FORECAST WILL START OUT COOL
AND...ASIDE FROM A FEW STRAY RAIN SHOWERS IN OUR FAR EASTERN
LOCATIONS EARLY FRIDAY MORNING...DRY AS A COLD FRONT MOVES OFF TO
THE EAST OF THE AREA. AS WINDS SHIFT TO THE WEST AND NORTHWEST
BEHIND THE BOUNDARY...MUCH COOLER AIR WILL SPILL INTO THE AREA.
AS THE RIDGE OF HIGH PRESSURE SETTLES OVER THE REGION...CLOUD
COVER WILL QUICKLY DECREASE IN COVERAGE AND MOVE OFF TO OUR EAST.
LIGHT WINDS AND THE CLEAR CONDITIONS WILL MAKE FOR A FAST COOL
DOWN FRIDAY NIGHT INTO SATURDAY MORNING. MOST OF OUR VALLEY
LOCATIONS...PARTICULARLY OUR EASTERN AND NORTHEASTERN VALLEYS...WILL
LIKELY FALL TO AROUND 30 BY SATURDAY MORNING...WITH THE MID 30S
EXPECTED EVERYWHERE ELSE. THESE CONDITIONS COULD LEAD TO FROST
FORMATION IN MOST OR ALL OF OUR VALLEYS. THIS COOL DOWN WILL BE
BRIEF...HOWEVER...AS THE AIR MASS WILL QUICKLY MODIFY OVER THE
UPCOMING WEEKEND...BRINGING MUCH WARMER WEATHER BACK TO EASTERN
KENTUCKY FROM SATURDAY AFTERNOON THROUGH THE BEGINNING OF THE NEW
WORK WEEK. ABUNDANT SUNSHINE AND SOUTHERLY FLOW WILL WARM THINGS UP
ON SATURDAY. TEMPERATURES SHOULD BE EVEN WARMER ON SUNDAY...AS THE
WINDS STRENGTHEN AHEAD OF AN APPROACHING WEATHER SYSTEM.
SHOWERS AND THUNDERSTORMS WILL ONCE AGAIN BE IN THE OFFING SUNDAY
AND SUNDAY NIGHT...AS A MORE POTENT WEATHER SYSTEM TAKES SHAPE TO
OUR WEST. THIS SYSTEM WILL ACTUALLY START OUT AS TWO SEPARATE
AREAS OF LOW PRESSURE...ONE THAT WILL FORM ALONG THE WESTERN END
OF A STALLED FRONTAL BOUNDARY OVER THE WESTERN GULF OF
MEXICO...AND FAST MOVING AREA OF LOW PRESSURE THAT IS FORECAST TO
MOVE ACROSS THE CENTRAL ROCKY MOUNTAINS AND OUT INTO THE WEST
CENTRAL PLAINS SATURDAY NIGHT. THESE TWO SYSTEMS ARE EXPECTED TO
PHASE A BIT SUNDAY NIGHT INTO A MORE CONSOLIDATED SYSTEM THAT WILL
BRING WIDESPREAD PRECIPITATION TO THE AREA.
ONCE THIS HYBRID LOW PRESSURE MOVES OUT OF THE AREA MONDAY
NIGHT...WE CAN EXPECTED ANOTHER PERIOD OF COOLER THAN NORMAL
WEATHER TO CLOSE OUT THE MONTH. HIGH TEMPERATURES OVER THE WEEKEND
WILL TOP OUT IN THE UPPER 60S ON SATURDAY...AND THE LOW TO MID 70S
ON SUNDAY. THE COOL DOWN BEHIND THE DEPARTING WEATHER SYSTEM WILL
QUITE PRONOUNCED...WITH HIGHS ON MONDAY ONLY MAKING IT TO AROUND
60S...WITH HIGHS ON TUESDAY MAXING OUT FROM THE MID TO UPPER 50S
IN OUR FAR NORTHERN COUNTIES...TO THE LOW 60S ALONG AND JUST NORTH
OF THE TENNESSEE BORDER. LOW TEMPERATURES AFTER SATURDAY NIGHT AND
SUNDAY NIGHT SHOULD GENERALLY BE IN THE 40S ACROSS THE AREA...WITH
UPPER 30S POSSIBLE MONDAY NIGHT INTO TUESDAY MORNING.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 808 PM EDT WED MAR 23 2016
EARLIER DAY STRATUS DECK CONTINUES TO RIDE NORTH OF THE OHIO RIVER
AS CIRRUS STREAMS IN FROM THE SOUTHWEST. AN AREA OF LOW PRESSURE
AND ASSOCIATED COLD FRONT WILL INTRODUCE VCSH CHANCES AT KSME BY
MID THURSDAY MORNING...WITH MORE WIDESPREAD SHRA CHANCES IMMINENT
BY MID-LATE AFTERNOON. THUNDER AND CB WILL ALSO POSE A THREAT
THROUGH THE AFTERNOON AND PERHAPS POST 00Z FRIDAY...BUT WILL
REFINE TIMING DETAILS BEFORE PLACING IN TAFS. BEFORE THEN...LOW
LEVEL WIND SHEAR WILL LIKELY DEVELOP AGAIN THIS EVENING THROUGH
TONIGHT WITH A LOW LEVEL WIND MAXIMUM MOVING OVERHEAD AHEAD OF THE
AFOREMENTIONED STORM SYSTEM. LOOK FOR SOUTH/SOUTHWEST SURFACE
WINDS TO INCREASE ABOVE 10 KNOTS AND BECOME GUSTY BY MID MORNING
THURSDAY AS CLOUD COVER THICKENS AND LOWERS THROUGH THE DAY. VFR
CEILINGS/VISIBILITIES SHOULD HOLD UNTIL THE MID-LATE AFTERNOON
HOURS FOR THE MOST PART. KJKL/KSJS MAY HOLD OFF ON SUB-VFR
CRITERIA UNTIL THURSDAY EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GUSEMAN
SHORT TERM...HAL
LONG TERM...AR
AVIATION...GUSEMAN
[top]
Area Forecast Discussion
National Weather Service Paducah KY
609 PM CDT WED MAR 23 2016
.UPDATE...
Issued at 608 PM CDT Wed Mar 23 2016
Updated Aviation discussion for 00Z TAF Issuance.
&&
.SHORT TERM...(This evening through Friday Night)
Issued at 250 PM CDT Wed Mar 23 2016
Considering all available 12Z guidance, it appears that the
convection will not reach our western counties until after 06Z
tonight. Some HRRR runs have shown some fairly intense convection
moving into the area, but it weakens considerably as it across
southeast Missouri. Certainly cannot rule out some isolated severe
in the far west, but nothing major. Heating has been held down
significantly today, and instability will be meager at best.
The models continue to solidify the precipitation as it moves
through our region Thursday, so QPF will increase to the east.
The convection will likely be intensifying in the late morning as
it exits to the east. Cannot argue with the slight risk areas in
SPC`s Day 1 and Day 2 outlooks. The mid and upper-level flow will
be nearly parallel to the convective line, so upscale growth of
the system and more widespread wind issues are not likely. So,
still would expect only isolated damaging winds, if only due to
the strong winds not far off the surface that may mix down with
any convective element.
It may be well into the afternoon before the last of the
precipitation exits the area, as the models continue to trend
slower with the system. This actually has a positive impact for
our area Thursday night and Friday morning, as the surface high
will not settle over our region until during the day Friday. This
should keep the entire area above freezing Friday morning. Cannot
rule out a very isolated location dropping right down to freezing
at sunrise over southeast Missouri or southern Illinois, but
nothing widespread or cold enough to warrant a Freeze Watch with
this forecast.
Winds will stay up through tonight, so temperatures are not likely
to drop much if at all tonight, until the precipitation moves in
very late. Used a combination of short range guidances to show
hourly trends in temperatures tonight and especially Thursday when
many locations will see falling temperatures at least in the
afternoon. Generally stayed on the warm side of guidance for
lows/highs from Thursday night through Friday night.
.LONG TERM...(Saturday through Wednesday)
Issued at 250 PM CDT Wed Mar 23 2016
A progressive pattern is expected through the long term, which will
keep the train of weather systems going. The first system will be on
Easter, followed by another potentially stronger system later next
week.
The long term will start off dry and mild, as surface high pressure
departs to our east Saturday. A southeast low-level wind flow and
plenty of sunshine will raise highs into the mid 60s for Saturday.
There is a large difference in model solutions for Easter Sunday,
but they all seem to agree on precip for our area. The gfs camp has
been especially inconsistent. The preferred model continues to be
the ecmwf, which has been more consistent. The 12z run of the ecmwf
has support from a couple of the gfs ensemble members. As far as the
surface low track, the 12z ecmwf is consistent with previous runs
and the 00z ecmwf ensemble mean. This set of models takes the
surface low northeast from Texas across southeast MO and southern
IL. This preferred model solution warm sectors our region, resulting
in higher temps Sunday and a continuation of the mention of thunder
in the forecast. Will raise pops back into the likely category for
most areas Sunday.
Monday will be mainly dry and cooler in the wake of the departing
cold front/low pressure system. Will hold onto a small pop for
southwest Indiana and the Pennyrile region, otherwise expect
clearing with highs around 60.
Tuesday looks dry and milder as the high moves well to the east of
our region. Some moisture will begin to stream northeast across our
region on Wednesday, in advance of a 500 mb trough or closed low
over the Western states. Other than a slight chance of precip in se
Missouri, will keep dry conditions going through Wed. Highs on Wed
should be mostly in the upper 60s with increasing southerly winds.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 608 PM CDT Wed Mar 23 2016
Still anticipate lower cigs/pcpn moving in later tonight and
continuing tmrw. Best chance of showers/storms tmrw first half of
day, including marginal risk of thunder, so included 30 pop for
that with IFR restrictions. Otherwise same with gusty sswlys tmrw
ahead of incoming system, shifting to west late.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
145 PM EDT TUE MAR 22 2016
.UPDATE...
ISSUED AT 145 PM EDT TUE MAR 22 2016
GETTING VERY CLOSE TO RED FLAG CONDITIONS...ESPECIALLY IN OUR
WESTERN COUNTIES. FORECAST IS ON TRACK AND NO NEED FOR ANY CHANGES
RIGHT NOW.
UPDATE ISSUED AT 1035 AM EDT TUE MAR 22 2016
UPDATED TO BUMP UP TEMPERATURES INTO THE MID 60S AS WE ARE ALREADY
REACHING THE LOWER 50S IN MANY SPOTS. ALSO LOWER DEWPOINTS...BASED
ON THE LOW READINGS ON THE HIGHER RIDGES IN THE SOUTHEAST. WE
SHOULD EASILY MIX DOWN THE DRIER AIR TODAY WITH ABUNDANT SUNSHINE.
NO OTHER CHANGES MADE AT THIS TIME.
UPDATE ISSUED AT 720 AM EDT TUE MAR 22 2016
DID A QUICK UPDATE TO FINE TUNE THE SKY/T/TD GRIDS PER THE LATEST
OBS AND TRENDS...THE REST OF THE FORECAST IS ON TRACK. THE UPDATED
GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT TUE MAR 22 2016
07Z SFC ANALYSIS SHOWS HIGH PRESSURE EDGING SOUTH OF KENTUCKY WITH
DEEP LOW PRESSURE DOMINATING THE UPPER MIDWEST. THE PRESSURE
GRADIENT BETWEEN THESE TWO SYSTEMS IS HELPING TO SUPPORT A DECENT
RIDGE VALLEY TEMPERATURE SPLIT TONIGHT UNDER MOSTLY CLEAR SKIES.
THE VALLEYS HAVE DECOUPLED WITH CALM WINDS...WHILE SOUTHWEST
BREEZES OF 5 TO 10 MPH KEEP THE RIDGES BETTER MIXED. THIS PRESSURE
GRADIENT WILL BE A BIG FACTOR IN THE FIRE WEATHER CONCERNS LATER
IN THE DAY. THE OTHER PART OF THE EQUATION FOR FIRE WEATHER IS DRY
AIR IN PLACE AT THE SFC...AND MORE SO THAT WHICH CAN BE BROUGHT
DOWN FROM ALOFT...DURING THE DAY. FOR EARLY THIS MORNING...
DEWPOINTS ARE RATHER DRY AND GENERALLY IN THE LOW TO MID 20S
WHETHER THE OBSERVATION SITE IN ON THE RIDGES...SPORTING AIR
TEMPERATURES IN THE LOW 40S...OR IN THE VALLEYS...AS SOME OF THE
MOST SHELTERED SPOTS ARE SEEING THEIR DRY BULB TEMPERATURES
APPROACH THE MID 20S. THIS HAS LIKELY LED TO PLENTY OF VALLEY
FROST ALONG WITH A SUSTAINED PERIOD OF SUB FREEZING
TEMPERATURES...HENCE THE FROST ADVISORY AND FREEZE WARNING IN
PLACE THROUGH 9 AM. THE RED FLAG WARNING THEN GOES INTO EFFECT AT
11 AM FOR THE ENTIRE AREA.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE LONGWAVE PATTERN
IN PLACE OVER THE REGION THROUGH THE SHORT TERM. THEY ALL DEPICT A
FLATTENING OVER KENTUCKY TODAY WITH SLIGHT RIDGING BUILDING NORTH
AND EAST FROM THE DEEP SOUTH. THIS RIDGE FURTHER SHARPENS OVERHEAD
INTO WEDNESDAY AS A FAIRLY DEEP TROUGH PUSHES INTO THE HIGH
PLAINS. HOWEVER...ANY ENERGY BREAKING FREE FROM THIS TROUGH WILL
STAY WELL NORTH OF KENTUCKY AS THE PACKETS MOVES EAST. GIVEN THE
MODEL AGREEMENT HAVE AGAIN FAVORED A GENERAL BLEND WITH A LEAN
TOWARD THE HRRR...RUC...AND NAM12 FOR SENSIBLE WEATHER THE NEAR
TERM.
SENSIBLE WEATHER WILL...AFTER A CHILLY AND FROSTY START IN THE
VALLEYS...FEATURE A SUNNY...WARM...DRY...AND BREEZY DAY WITH THE
WINDS PICKING UP FROM THE SOUTHWEST BY MIDDAY. A FAIRLY HIGH
MIXING LEVEL THROUGH EARLY AFTERNOON WILL SUPPORT GUSTY WINDS AND
EXTRA DRY AIR BROUGHT DOWN TO THE SFC. THIS WILL LEAD TO ENHANCED
FIRE CONDITIONS FOR THE ENTIRE AREA...THOUGH WINDS WILL BE MORE
BORDERLINE IN THE EAST THAN THE WEST DURING THE AFTERNOON...EXCEPT
ON THE RIDGES. CONDITIONS WILL IMPROVE THIS EVENING WHEN THE
WINDS SETTLE AND RH REBOUNDS. FOR TONIGHT...ANOTHER DECENT RIDGE
TO VALLEY TEMPERATURE SPLIT WILL SET UP OWING TO SIMILAR
CONDITIONS AS THIS MORNING AND STILL MAINLY CLEAR SKIES.
WEDNESDAY WILL SEE A TAD MORE CLOUDS...BUT STILL BE MOSTLY
SUNNY...WARM...AND BREEZY. IN FACT...FIRE WEATHER CONDITIONS COULD
BE A CONCERN FOR WEDNESDAY AFTERNOON...AS WELL...THOUGH THE WINDS
SHOULD BE A NOTCH LIGHTER ALONG WITH SLIGHTLY LESS DRY HUMIDITY
LEVELS.
USED THE SHORTBLEND GUIDANCE FOR THE T/TD/WIND GRIDS AGAIN AS A
STARTING POINT THROUGH THE DAY AND THE SUPERBLEND THEREAFTER. HAVE
ADJUSTED THESE MAINLY TO SIGNIFICANTLY ADJUST FOR TERRAIN
DIFFERENCES IN THE LOWS AND HOURLY TEMPS TONIGHT...BUT ALSO TOOK
THE DEWPOINTS DOWN A CATEGORY BOTH AFTERNOONS FOR ENHANCED DRY
AIR MIX-DOWN ANTICIPATED. AS FOR POPS...ZEROED THEM OUT ACROSS
EAST KENTUCKY...IN LINE WITH ALL MOS GUIDANCE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 356 AM EDT TUE MAR 22 2016
WE BEGIN THE PERIOD IN THE MIDDLE OF A HIGH PRESSURE CENTERED OF
THE ATLANTIC COAST AND A DEEPENING SURFACE LOW IN THE CENTRAL
PLAINS. THEREFORE WE WILL REMAIN MIXED AT LEAST IN THE HIGHER
TERRAIN WITH GRADIENT STAYING FAIRLY TIGHT. OVERALL CLOUDS WILL
BEGIN TO INCREASE AS MOISTURE CONTINUES TO RETURN. THE
AFOREMENTIONED SURFACE LOW STILL LOOKS TO EJECT NORTHEAST INTO
THE GREAT LAKES AS UPPER LEVEL WAVE SWINGS ACROSS THE OHIO VALLEY.
OVERALL THE MODELS REMAIN IN FAIRLY GOOD AGREEMENT WITH DEFINITE
POPS ON THURSDAY INTO THURSDAY EVENING...HOWEVER THE 00Z ECMWF IS
PERSISTENT WITH A SLOWER PROGRESS EAST. RIGHT NOW WILL STICK
FAIRLY CLOSE TO THE BLEND OF POPS...BUT WILL TRY TO PROGRESS THE
SYSTEM ACROSS THE REGION WITH COLD FRONT. OVERALL THE SYSTEM LOOKS
PROGRESSIVE AND STILL SOME CONCERN ON THE AMOUNT OF MOISTURE WE
ACTUALLY REALIZE. RIGHT NOW WILL REMAIN OPTIMISTIC LOOKING AT THE
TIME HEIGHTS...WITH BOTH DEEP MOISTURE AND OMEGA INDICATING A
PERIOD OF DECENT RAIN ACROSS EASTERN KENTUCKY. THIS WILL BE MUCH
NEEDED GIVEN VERY DRY ANTECEDENT CONDITIONS TODAY AND WEDNESDAY.
MODEL SOUNDINGS STILL INDICATING FAIRLY MEAGER
INSTABILITY...HOWEVER SHOULD BE ENOUGH TO SEE A FEW STORMS. ALSO
GIVEN THE STRONG JET ENERGY ALOFT WOULD THINK ANY OF THE STORMS
THAT DO DEVELOP WOULD HAVE THE POTENTIAL TO MIX DOWN SOME GUSTY
WINDS.
POPS LOOK TO FALL OFF QUICKLY THURSDAY NIGHT AS HIGH PRESSURE
BUILDS EAST. WE DO SEE A QUICK SHOT OF COLD AIR WITH THIS FRONT AS
850 MB TEMPS DROP INTO THE -4 TO -6 RANGE. WHILE WE CLEAR OUT ON
FRIDAY...AS DRY AIR CONTINUES TO INCREASE ACROSS THE REGION...WE
ONLY CLIMB INTO THE LOWER 50S ON THE COLD SIDE OF THE SURFACE
HIGH. THEREFORE ANOTHER CLEAR AND COLD NIGHT WILL BE ON TAP FOR
YOU FRIDAY NIGHT. THIS WILL LEAD TO ANOTHER NIGHT OF PATCHY FROST
AND FREEZING TEMPS IN THE SHELTER VALLEY SPOTS...THEREFORE WILL
KEEP THIS HIGHLIGHTED IN THE HWO FOR NOW. TEMPS LOOK TO RECOVER
SATURDAY AS WE BEGIN TO GET BACK IN THE RETURN FLOW SIDE OF THE
SURFACE HIGH PRESSURE. NOW LATE PERIOD GUIDANCE BEGINS TO DIVERGE
A BIT WITH THE NEXT DISTURBANCE. ONCE AGAIN THE 00Z GFS REMAINS
FASTER AND BRINGS OVERRUNNING ACROSS THE REGION BY SUNDAY...WHILE
THE 00Z ECMWF HOLD OFF TIL SUNDAY NIGHT AND WOULD DEVELOP A DEEPER
SURFACE LOW. RIGHT NOW THESE DIFFERENCES LOOK TO BE WITH RESPECT
TO THE HIGHER AMPLITUDE AND CLOSED VERSUS OPEN WAVE...WITH THE
ECMWF PROJECTING A CLOSED UPPER LOW. RIGHT NOW WILL STICK WITH THE
MODEL BLEND...GIVEN WE LOOK TO SEE A DECENT SYSTEM TOWARD THE END
OF THE WEEKEND IT PAINTS LIKELY POPS ACROSS THE REGION SUNDAY
NIGHT. RIGHT NOW MODEL SOUNDINGS DO SUPPORT DECENT INSTABILITY AND
ENOUGH TO BEGIN INCLUDING THIS THOUGHT IN THE GRIDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 145 PM EDT TUE MAR 22 2016
VFR CONDITIONS WILL CONTINUE OVER EAST KENTUCKY FOR THE NEXT 24
TO 36 HOURS. A STRENGTHENING PRESSURE GRADIENT ACROSS THE AREA
WILL LEAD TO GUSTY SOUTHWEST WINDS DEVELOPING THIS AFTERNOON... IN
THE RANGE OF 15 TO 25 KTS WITH THE HIGHER VALUES FOUND TO THE
WEST.
&&
.FIRE WEATHER...
ISSUED AT 315 AM EDT TUE MAR 22 2016
LOW AFTERNOON/EVENING RELATIVE HUMIDITIES WILL CONTINUE THROUGH
WEDNESDAY. AS THE PRESSURE GRADIENT TIGHTENS UP TODAY...
SUSTAINED WINDS OF 15 TO 20 MPH WILL BE POSSIBLE...ESPECIALLY OVER
WESTERN PARTS OF THE AREA AND PERHAPS LIMITED TO RIDGES IN THE
EAST. THE COMBINATION OF LOW RH AND HIGHER WINDS WILL LEAD TO
ELEVATED FIRE DANGER TODAY AND WEDNESDAY...EXCEEDING CRITICAL
FIRE WEATHER THRESHOLDS. FOR THIS REASON...WE HAVE ISSUED A RED
FLAG WARNING. GUSTY WINDS ARE EXPECTED AGAIN ON WEDNESDAY...BUT
RELATIVE HUMIDITIES MAY COME UP SOME BY THEN. A COLD FRONT THEN
LOOKS TO BRING SOME MUCH NEEDED RAIN TO THE AREA ON THURSDAY WITH
AMOUNTS UP TO AN INCH POSSIBLE AND BASIN AVERAGES AROUND A HALF AN
INCH EXPECTED.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 9 PM EDT THIS EVENING FOR KYZ044-050>052-
058>060-068-069-079-080-083>088-104-106>120.
&&
$$
UPDATE...KAS
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...KAS
FIRE WEATHER...GREIF
Area Forecast Discussion
National Weather Service Paducah KY
1235 PM CDT TUE MAR 22 2016
.UPDATE...
Issued at 1235 PM CDT Tue Mar 22 2016
The latest short term guidance is not real excited about 45mph
gusts this afternoon, but they will be close enough to allow the
Wind Advisory to continue through the afternoon. We are closely
monitoring RH and winds across west Kentucky for fire weather
concerns.
The AVIATION section has been updated for the 18Z TAF issuance.
&&
.SHORT TERM...(Today through Thursday night)
Issued at 332 AM CDT Tue Mar 22 2016
Will issue a Wind Advisory for the west 2/3 of the area given
momentum transfer values seen in Bufkit GFS/NAM in the mixed layer
below 850mb. We usually end up at or just above these values.
Looking upstream at sfc obs, near term high res dew point
forecasts seem too high. We lowered values. Otherwise high clouds
today. Still breezy tonight. Increasing low level moisture should
result in more cloud cover by Wednesday morning. Through the day
Wednesday, the models (for 3 days now), show a very strong cap aoa
850mb with all moisture below the cap. Maybe sprinkles at best.
Agree with previous shift, warm advection will tend to lift the
inversion. Soundings show that, but probably not until the end of
the day. Probably mostly clouds with a lack of focus and NVA aloft
across the area. Temps a MOS blend. Lower confidence Wednesday in
warmer MAV given clouds. Went closer to ECS MOS values.
For the Wednesday night through Thursday time frame, we will
continue to gear PoPs toward the ECMWF/NAM and somewhat the CMC.
The GFS continues to appear too fast. These trends have existed
for the past 3 days. The upper system should be over NE KS/NW MO
06z Thursday with a sfc low over NW MO. The upper low should reach
NW IL by 18z with the sfc low over northern IN. Surface front at
12z Thursday should just be entering our western most counties of
SEMO. At 18z the front should be from SW IN into the KY Pennyrile.
Will increase PoPs from west to east Wednesday night for showers
and thunderstorms. Best PoPs Thursday morning will be across the
eastern 2/3 of the area, decreasing chances fairly quickly during
the afternoon from west to east. Some strong storms will be
possible Wednesday night into Thursday morning, given decent wind
fields, modest surface based instability and lowering freezing
levels. Thursday night will be dry with high pressure building in.
.LONG TERM...(Friday through Monday)
Issued at 332 AM CDT Tue Mar 22 2016
Sfc high pressure will be centered over us Friday morning, which
will allow for a very cold start, with morning lows bottoming out in
the lower 30s. This high will shift east throughout the day on
Friday/Friday night and winds will eventually shift back to
southeasterly as this occurs. Temperatures will be below normal for
Friday and only be in the low to mid 50s.
Our attention then turns to our next weather system. The GFS
continues to be the quickest model and brings the next cold front
through the area Saturday night into Sunday. The ECMWF is consistent
with a slower solution. In addition, the last couple of ECMWF runs
indicates a sfc low forming to our west along the front which moves
northeast across south central IL Sunday into Monday. This is in
response to an upper level low that develops in MO/IL. This would
indicate better chances for rain later in the weekend and continuing
into early Monday.
Looking at the GFS ensembles, it indicates a fairly progressive
trough moving through but tends to linger QPF a bit longer than the
operational GFS. Still too far out in time to nail down a perfect
time for precip. There are some indications of thunder as well,
especially when we get to Sunday and/or Sunday night.
Temperatures over the weekend should be in the 60s with a cool down
behind the front by Monday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1235 PM CDT Tue Mar 22 2016
Gusty south southwest winds have developed as expected and should
continue to strengthen through the afternoon. Frequent gusts over
30kts will be the rule with the possible exception of KPAH. Winds
will stay up tonight, and gusts are likely. If the winds drop off
more tonight, LLWS will be a concern. All available guidance
brings a rapid increase in low-level moisture/clouds through all
the TAF sites late tonight or tomorrow morning, but the timing is
varied. Tried to find the middle ground. Also have lower MVFR
ceilings at KCGI and KPAH than at KEVV and KOWB.
&&
.FIRE WEATHER...
Issued at 332 AM CDT Tue Mar 22 2016
Will monitor elevated fire danger concerns closely through the day
given strong SSW winds 20 to 30 mph with gusts 40 to 45 mph. This
combined with dry fuels, and humidity levels from the upper 20 to
mid 30s (percent), will present an elevated fire concern. Best
chance of meeting criteria will be across west Kentucky. We can
coordinate this with fire weather officials shortly after daybreak
and see if any headlines are needed.
&&
.PAH Watches/Warnings/Advisories...
IL...Wind Advisory until 7 PM CDT this evening for ILZ075>078-080>094.
MO...Wind Advisory until 7 PM CDT this evening for MOZ076-086-087-100-
107>112-114.
IN...None.
KY...Wind Advisory until 7 PM CDT this evening for KYZ001>007.
&&
$$
UPDATE...DRS
SHORT TERM...CN
LONG TERM....CW
AVIATION...DRS
Area Forecast Discussion
National Weather Service Paducah KY
1235 PM CDT TUE MAR 22 2016
.UPDATE...
Issued at 1235 PM CDT Tue Mar 22 2016
The latest short term guidance is not real excited about 45mph
gusts this afternoon, but they will be close enough to allow the
Wind Advisory to continue through the afternoon. We are closely
monitoring RH and winds across west Kentucky for fire weather
concerns.
The AVIATION section has been updated for the 18Z TAF issuance.
&&
.SHORT TERM...(Today through Thursday night)
Issued at 332 AM CDT Tue Mar 22 2016
Will issue a Wind Advisory for the west 2/3 of the area given
momentum transfer values seen in Bufkit GFS/NAM in the mixed layer
below 850mb. We usually end up at or just above these values.
Looking upstream at sfc obs, near term high res dew point
forecasts seem too high. We lowered values. Otherwise high clouds
today. Still breezy tonight. Increasing low level moisture should
result in more cloud cover by Wednesday morning. Through the day
Wednesday, the models (for 3 days now), show a very strong cap aoa
850mb with all moisture below the cap. Maybe sprinkles at best.
Agree with previous shift, warm advection will tend to lift the
inversion. Soundings show that, but probably not until the end of
the day. Probably mostly clouds with a lack of focus and NVA aloft
across the area. Temps a MOS blend. Lower confidence Wednesday in
warmer MAV given clouds. Went closer to ECS MOS values.
For the Wednesday night through Thursday time frame, we will
continue to gear PoPs toward the ECMWF/NAM and somewhat the CMC.
The GFS continues to appear too fast. These trends have existed
for the past 3 days. The upper system should be over NE KS/NW MO
06z Thursday with a sfc low over NW MO. The upper low should reach
NW IL by 18z with the sfc low over northern IN. Surface front at
12z Thursday should just be entering our western most counties of
SEMO. At 18z the front should be from SW IN into the KY Pennyrile.
Will increase PoPs from west to east Wednesday night for showers
and thunderstorms. Best PoPs Thursday morning will be across the
eastern 2/3 of the area, decreasing chances fairly quickly during
the afternoon from west to east. Some strong storms will be
possible Wednesday night into Thursday morning, given decent wind
fields, modest surface based instability and lowering freezing
levels. Thursday night will be dry with high pressure building in.
.LONG TERM...(Friday through Monday)
Issued at 332 AM CDT Tue Mar 22 2016
Sfc high pressure will be centered over us Friday morning, which
will allow for a very cold start, with morning lows bottoming out in
the lower 30s. This high will shift east throughout the day on
Friday/Friday night and winds will eventually shift back to
southeasterly as this occurs. Temperatures will be below normal for
Friday and only be in the low to mid 50s.
Our attention then turns to our next weather system. The GFS
continues to be the quickest model and brings the next cold front
through the area Saturday night into Sunday. The ECMWF is consistent
with a slower solution. In addition, the last couple of ECMWF runs
indicates a sfc low forming to our west along the front which moves
northeast across south central IL Sunday into Monday. This is in
response to an upper level low that develops in MO/IL. This would
indicate better chances for rain later in the weekend and continuing
into early Monday.
Looking at the GFS ensembles, it indicates a fairly progressive
trough moving through but tends to linger QPF a bit longer than the
operational GFS. Still too far out in time to nail down a perfect
time for precip. There are some indications of thunder as well,
especially when we get to Sunday and/or Sunday night.
Temperatures over the weekend should be in the 60s with a cool down
behind the front by Monday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1235 PM CDT Tue Mar 22 2016
Gusty south southwest winds have developed as expected and should
continue to strengthen through the afternoon. Frequent gusts over
30kts will be the rule with the possible exception of KPAH. Winds
will stay up tonight, and gusts are likely. If the winds drop off
more tonight, LLWS will be a concern. All available guidance
brings a rapid increase in low-level moisture/clouds through all
the TAF sites late tonight or tomorrow morning, but the timing is
varied. Tried to find the middle ground. Also have lower MVFR
ceilings at KCGI and KPAH than at KEVV and KOWB.
&&
.FIRE WEATHER...
Issued at 332 AM CDT Tue Mar 22 2016
Will monitor elevated fire danger concerns closely through the day
given strong SSW winds 20 to 30 mph with gusts 40 to 45 mph. This
combined with dry fuels, and humidity levels from the upper 20 to
mid 30s (percent), will present an elevated fire concern. Best
chance of meeting criteria will be across west Kentucky. We can
coordinate this with fire weather officials shortly after daybreak
and see if any headlines are needed.
&&
.PAH Watches/Warnings/Advisories...
IL...Wind Advisory until 7 PM CDT this evening for ILZ075>078-080>094.
MO...Wind Advisory until 7 PM CDT this evening for MOZ076-086-087-100-
107>112-114.
IN...None.
KY...Wind Advisory until 7 PM CDT this evening for KYZ001>007.
&&
$$
UPDATE...DRS
SHORT TERM...CN
LONG TERM....CW
AVIATION...DRS
Area Forecast Discussion
National Weather Service Paducah KY
1235 PM CDT TUE MAR 22 2016
.UPDATE...
Issued at 1235 PM CDT Tue Mar 22 2016
The latest short term guidance is not real excited about 45mph
gusts this afternoon, but they will be close enough to allow the
Wind Advisory to continue through the afternoon. We are closely
monitoring RH and winds across west Kentucky for fire weather
concerns.
The AVIATION section has been updated for the 18Z TAF issuance.
&&
.SHORT TERM...(Today through Thursday night)
Issued at 332 AM CDT Tue Mar 22 2016
Will issue a Wind Advisory for the west 2/3 of the area given
momentum transfer values seen in Bufkit GFS/NAM in the mixed layer
below 850mb. We usually end up at or just above these values.
Looking upstream at sfc obs, near term high res dew point
forecasts seem too high. We lowered values. Otherwise high clouds
today. Still breezy tonight. Increasing low level moisture should
result in more cloud cover by Wednesday morning. Through the day
Wednesday, the models (for 3 days now), show a very strong cap aoa
850mb with all moisture below the cap. Maybe sprinkles at best.
Agree with previous shift, warm advection will tend to lift the
inversion. Soundings show that, but probably not until the end of
the day. Probably mostly clouds with a lack of focus and NVA aloft
across the area. Temps a MOS blend. Lower confidence Wednesday in
warmer MAV given clouds. Went closer to ECS MOS values.
For the Wednesday night through Thursday time frame, we will
continue to gear PoPs toward the ECMWF/NAM and somewhat the CMC.
The GFS continues to appear too fast. These trends have existed
for the past 3 days. The upper system should be over NE KS/NW MO
06z Thursday with a sfc low over NW MO. The upper low should reach
NW IL by 18z with the sfc low over northern IN. Surface front at
12z Thursday should just be entering our western most counties of
SEMO. At 18z the front should be from SW IN into the KY Pennyrile.
Will increase PoPs from west to east Wednesday night for showers
and thunderstorms. Best PoPs Thursday morning will be across the
eastern 2/3 of the area, decreasing chances fairly quickly during
the afternoon from west to east. Some strong storms will be
possible Wednesday night into Thursday morning, given decent wind
fields, modest surface based instability and lowering freezing
levels. Thursday night will be dry with high pressure building in.
.LONG TERM...(Friday through Monday)
Issued at 332 AM CDT Tue Mar 22 2016
Sfc high pressure will be centered over us Friday morning, which
will allow for a very cold start, with morning lows bottoming out in
the lower 30s. This high will shift east throughout the day on
Friday/Friday night and winds will eventually shift back to
southeasterly as this occurs. Temperatures will be below normal for
Friday and only be in the low to mid 50s.
Our attention then turns to our next weather system. The GFS
continues to be the quickest model and brings the next cold front
through the area Saturday night into Sunday. The ECMWF is consistent
with a slower solution. In addition, the last couple of ECMWF runs
indicates a sfc low forming to our west along the front which moves
northeast across south central IL Sunday into Monday. This is in
response to an upper level low that develops in MO/IL. This would
indicate better chances for rain later in the weekend and continuing
into early Monday.
Looking at the GFS ensembles, it indicates a fairly progressive
trough moving through but tends to linger QPF a bit longer than the
operational GFS. Still too far out in time to nail down a perfect
time for precip. There are some indications of thunder as well,
especially when we get to Sunday and/or Sunday night.
Temperatures over the weekend should be in the 60s with a cool down
behind the front by Monday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1235 PM CDT Tue Mar 22 2016
Gusty south southwest winds have developed as expected and should
continue to strengthen through the afternoon. Frequent gusts over
30kts will be the rule with the possible exception of KPAH. Winds
will stay up tonight, and gusts are likely. If the winds drop off
more tonight, LLWS will be a concern. All available guidance
brings a rapid increase in low-level moisture/clouds through all
the TAF sites late tonight or tomorrow morning, but the timing is
varied. Tried to find the middle ground. Also have lower MVFR
ceilings at KCGI and KPAH than at KEVV and KOWB.
&&
.FIRE WEATHER...
Issued at 332 AM CDT Tue Mar 22 2016
Will monitor elevated fire danger concerns closely through the day
given strong SSW winds 20 to 30 mph with gusts 40 to 45 mph. This
combined with dry fuels, and humidity levels from the upper 20 to
mid 30s (percent), will present an elevated fire concern. Best
chance of meeting criteria will be across west Kentucky. We can
coordinate this with fire weather officials shortly after daybreak
and see if any headlines are needed.
&&
.PAH Watches/Warnings/Advisories...
IL...Wind Advisory until 7 PM CDT this evening for ILZ075>078-080>094.
MO...Wind Advisory until 7 PM CDT this evening for MOZ076-086-087-100-
107>112-114.
IN...None.
KY...Wind Advisory until 7 PM CDT this evening for KYZ001>007.
&&
$$
UPDATE...DRS
SHORT TERM...CN
LONG TERM....CW
AVIATION...DRS
Area Forecast Discussion
National Weather Service Louisville KY
1240 PM EDT TUE MAR 22 2016
...Updated Aviation Discussion...
...Forecast Update...
Updated 1056 AM EDT Tue Mar 22 2016
Current forecast remains on track in the short term. We did lower
dewpoints slightly in the east given current observations. We
adjusted dewpoints more toward the latest HRRR runs which allows
dewpoints to drop into the lower 20s this afternoon. Afternoon
relative humidity values may drop into the 23-29% range for a time
out near the I-75 corridor. In addition gusty southwest winds of 15
to 20 MPH with gusts up to 30-35 MPH will combine with the low
humidity to produce heightened wildfire conditions across the
region. We will continue to coordinate with local forestry
officials to see if any additional headlines will be needed later
this morning and into the afternoon.
.SHORT TERM (Now through Wednesday)...
Issued at 303 AM EDT Tue Mar 22 2016
The short term will be dominated by warm and dry southerly surface
flow as we sit between high pressure moving off the southeast coast
and low pressure organizing over the central Plains. The models do
print out some light QPF Wednesday over the northwest LMK CWA but
this may be overdone. Atmospheric cross-sections show only shallow
moisture and MOS PoPs are mostly in the single digits over much of
the CWA. So, after chatting with PAH, will have a dry forecast for
Wednesday.
A tight surface gradient and abundant insolation (especially today)
will lead to windy conditions throughout the short term. Winds will
gust to 30, possibly 35, mph this afternoon, and into the 25-30mph
range Wednesday afternoon. We`ll get close to Wind Advisory this
afternoon. For now, with the forecast below advisory thresholds,
will stick with an SPS.
Dry air and turbulent mixing on the soundings suggest dew points
this afternoon bottoming out from the upper 20s from Lake Cumberland
to the Blue Grass Army Depot...to the middle and upper 30s towards
Hoosier National Forest. This plus the wind gusts and low fuel
moisture will lead to a heightened fire danger today, especially in
the Blue Grass and Lake Cumberland regions. We`ll coordinate with
fire officials and surrounding NWS offices later this morning to
determine the need for any headlines.
Higher dew points streaming from the Gulf into the Arklatex today
will finally make it to central Kentucky and southern Indiana
tomorrow, helping to slightly lower fire risk. Still, winds will be
gusty and fuel moisture levels low, so caution will need to be
exercised.
High temperatures today will be in the middle and upper 60s. Temps
will stay up tonight ahead of the approaching Plains system and with
southerly breezes continuing. Lows should be around 50. On Wednesday
southerly flow will continue and a cold front will be nearing from
the west, but increasing clouds will offset temps a bit, so will
once again forecast highs in the middle and upper 60s.
.LONG TERM (Wednesday Night through Monday)...
Issued at 316 AM EDT Tue Mar 22 2016
Surface low pressure near Kansas City Wednesday evening will proceed
to Chicago by Thursday morning and Lake Erie by that evening,
pulling its cold front through here on Thursday. Gulf moisture will
be plentiful and widespread showers are expected late Wednesday
night through Thursday afternoon. Instability will be weak and
elevated with this system. Thunder will be a possibility but severe
weather looks unlikely so far.
With the cold front approaching, widespread clouds overhead, and
southerly winds keeping up overnight, went above guidance for lows
Wednesday night in the 55-60 degree range. Not much recovery on
Thursday, though, with clouds and rain.
The cold front and associated upper trof axis will move through
Thursday night, bringing an end to the showers. High pressure will
provide us with dry and pleasant weather Friday and Saturday, though
the mornings will be cool. Some patchy frost could form in sheltered
spots, but the wind may stay up just enough Friday morning and
temperatures may stay just warm enough Saturday morning to keep
frost from becoming widespread or heavy.
The next upper trof will dig into the Plains late in the week and
approach us by Sunday/Monday, causing showers and a few
thunderstorms to return to the forecast for the second half of the
weekend and the first part of the new week.
&&
.AVIATION (18Z TAF Update)...
Updated at 1240 PM EDT Tue Mar 22 2016
Winds have become quite gusty early this afternoon in response to
the tightening pressure gradient across the region. Winds through
the afternoon hours will continue in the 15-20 knot range with gusts
as high as 30 knots. Winds will relax a bit overnight, but the
boundary layer will remain well mixed with gusts out of the south-
southwest of up to 20 knots through the night. The low level jet
will increase overnight. However, with the boundary layer remaining
well mixed and the inversion setting up above the low level jet,
have decided not to put LLWS in the TAFs at this time. Gusts will
pick up above 20 knots again tomorrow morning. In addition, low
level moisture will lead to increased low level cloudiness
tomorrow morning, though ceilings look to remain VFR at this time.
&&
.LMK Watches/Warnings/Advisories...
KY...NONE.
IN...NONE.
&&
$$
Update.........MJ
Short Term.....13
Long Term......13
Aviation.......EER
AREA FORECAST DISCUSSION...UPDATED
NWS BALTIMORE MD/WASHINGTON DC
947 PM EDT WED MAR 23 2016
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE WESTERN ATLANTIC THROUGH
THURSDAY. A COLD FRONT WILL PASS THROUGH THE AREA LATE THURSDAY
NIGHT INTO FRIDAY. HIGH PRESSURE WILL RETURN FOR SATURDAY INTO
SUNDAY...BUT LOW PRESSURE WILL LIKELY IMPACT THE AREA EARLY NEXT
WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
CLEAR SKIES EXPECTED OVERNIGHT. LOW TEMPS IN THE MID-UPPER 40S.
SEE UPDATED FIRE WX DISCUSSION FOR TOMORROW. A FIRE WX WATCH HAS
BEEN ISSUED.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
THURSDAY WILL BE SIMILAR TO TODAY BUT WITH LESS HIGH CLOUDS AND
SLIGHTLY WARMER MAX TEMPS. THE REDUCED AMOUNT OF HIGH CLOUDS WILL
ALLOW MORE MIXING WITH GUSTIER SW WINDS. BOTH THE 12Z GFS AND 00Z
ECMWF HAS COLD FROPA THURSDAY NIGHT WITH THE FRONT CLEARING THE
CWA ON FRIDAY MORNING. MODERATE CONFIDENCE OF SHOWERS FROM LATE
EVENING THURSDAY THROUGH EARLY FRIDAY MORNING. FRIDAY WILL BE IN
NORTHWEST FLOW BEHIND THE FRONT...BUT WITH H5 PVA BEHIND IT...MAY
TOUCH OF ISOLATED SHOWERS ESP AT HIGHER ELEVATIONS IN NORTHERN AND
WESTERN PORTION OF CWA. USED THE SUPERBLEND FOR MAX/MIN TEMPS
THROUGH FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
DRY CONDITIONS EXPECTED FOR SAT AND SUN WITH HIGH PRESS TO OUR
NORTH/NORTHEAST. A LOW PRESS SYSTEM WILL TRACK TO OUR NORTHWEST
SOMETIME SUN NIGHT INTO MON... PUSHING A COLD FRONT THROUGH OUR
REGION SOMETIME ON MON... WITH PRECIP PSBLY STARTING SUN NIGHT.
TIMING WITH THE FROPA IS STILL UNCERTAIN BETWEEN GUIDANCE... AS
WELL AS PRECIP DURATION.
HIGH PRESS BUILDS BEHIND COLD FRONT MON OR MON NIGHT BRINGING BACK
DRY CONDITIONS THROUGH WED. TEMPS WILL BE NEAR OR SLIGHTLY ABOVE
NORMAL... HIGH TEMPS IN THE 50S AND 60S. LOW TEMPS WILL IN THE 40S
AND 50S... AND IN THE 30S AT HIGHER ELEVATIONS.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
VFR AT ALL TERMINALS THROUGH THE TAF FORECAST PERIOD. THURSDAY
NIGHT...EXPECTING MVFR-IFR CONDITIONS FOR CIGS AND
VSBYS...CONTINUING THROUGH FRIDAY MORNING AT KDCA AND KBWI. GUSTY
SOUTHWESTERLY WINDS ARE EXPECTED IN THE 22KT-28KT RANGE THURSDAY
AFTERNOON AT ALL TERMINALS.
VFR CONDITIONS EXPECTED FOR SAT AND SUN WITH HIGH PRESS TO OUR
NORTH/NORTHEAST.
&&
.MARINE...
LATEST RAP FORECAST DOES HAVE WINDS MIXING DOWN FOR THE REMAINDER
OF THE AFTERNOON AOA SCA CRITERIA...SO WILL KEEP IT INTACT.
HOWEVER...WITH THE WARM AIR ADVECTION OVER THE COLDER
WATERS...EXPECTING THE SCA WINDS TO BE LIMITED TO NEARSHORE.
MODELS STILL SHOW THE BIG WATER OF THE TIDAL POTOMAC AND
CHESAPEAKE ADJACENT TO SOUTHERN MARYLAND IN SCA TONIGHT...AND
THEN THERE SHOULD BE A SOLID SCA AFTER THE INVERSION BREAKS
TOMORROW MORNING AND WILL EXTEND THE SCA THROUGH THURSDAY NIGHT.
SUB-SCA CONDITIONS EXPECTED SAT INTO SUN WITH HIGH PRESS TO OUR
NORTH/NORTHEAST.
&&
.FIRE WEATHER...
AFTER EXTENSIVE COORDINATION WITH RNK...MD AND VA FORESTRY A FIRE
WX WATCH HAS BEEN ISSUED FOR TOMORROW DUE TO STRONG WINDS AND LOW
HUMIDITIES. WHILE DEWPOINTS AND RH WILL BE HIGHER TOMORROW (ABT 5F
AND 5% HIGHER) THAN TODAY...RH VALUES DON`T APPEAR WILL BE HIGH
ENOUGH ABOVE THE 30% CRITICAL THRESHOLD FOR RED FLAGS. MIN_RH
VALUES TODAY WERE IN THE MID TEENS IN THE SOUTHERN PART OF THE CWA
AND IN THE 20S IN NORTHERN VA AND CENTRAL MD. WINDS WILL BE
SIGNIFICANTLY STRONGER TOMORROW WITH O-1 KM MEAN FLOW OF OVER 20KT
WITH GUSTS OVER 30KT.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR DCZ001.
MD...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR MDZ003>006-011-013-014-016>018-501>508.
VA...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR VAZ025>031-036>040-050>057-501>508.
WV...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR WVZ050>053-055-501>506.
MARINE...SMALL CRAFT ADVISORY FROM 11 AM THURSDAY TO 6 AM EDT FRIDAY
FOR ANZ530>532-535-536-538>540.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT FRIDAY FOR ANZ533-534-537-
541>543.
&&
$$
SYNOPSIS...LEE
NEAR TERM...LFR
SHORT TERM...LFR
LONG TERM...IMR
AVIATION...IMR/LFR
MARINE...IMR/LFR
FIRE WEATHER...LFR
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
539 PM EDT TUE MAR 22 2016
.SYNOPSIS...
TEMPERATURES WILL WARM AHEAD OF A THURSDAY COLD FRONT.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
ONLY COSMETIC CHANGES WERE MADE TO THE EARLY EVENING UPDATE. HAVE
ADJUSTED DEW POINTS BASED ON LATEST OBSERVATIONS AND FORECASTED
THEM USING THE LATEST RUC GUIDANCE. PREVIOUS DISCUSSION FOLLOWS.
A NEARLY STATIONARY FRONTAL BOUNDARY OVER THE GREAT LAKES WILL
REMAIN THE FOCUS FOR RAIN CHANCES DURING THE NEAR TERM PERIOD AS
A COUPLE OF SHORTWAVES IN ZONAL FLOW TRAVERSES THE REGION. SLIGHT
SHOWER CHANCES FOR AREAS NORTH OF I 80 WERE THUS MAINTAINED GIVEN
THE RELATIVE PROXIMITY TO THE FRONT...BUT DRY WEATHER WILL PREVAIL
FOR THE UPPER OHIO VALLERY REGION.
TEMPERATURES WILL ALSO MODERATE TO 5 TO 10 DEGREES ABOVE THE AVGS
AS WARM ADVECTION INTENSIFIES TO THE SOUTH OF THAT FRONTAL
BOUNDARY. SUPERBLEND GUIDANCE/PERSISTENCE WAS USED FOR TONIGHTS
LOWS...AND WEDNESDAY HIGHS.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
A DEEP UPPER LEVEL TROUGH AND ASSOCIATED SURFACE COLD FRONT ARE
PROJECTED FOR A THURSDAY APPROACH...AND NIGHTIME PASSAGE ACRS THE
UPPER OHIO REGION. INCREASING POPS WERE MAINTAINED FOR THAT TIME
FRAME...WITH CUMULATION IN CATEGORICAL NUMBERS. THUNDER STILL
LOOKS POSSIBLE WITH FRONT...BUT MODELS DIFFER IN THE MAGNITUDE OF
BOUNDARY LAYER MOISTURE/HENCE INSTABILTY. DESPITE IMPRESSIVE DEEP
LAYER SHEAR...SEVERE STORMS ARE UNLIKELY DUE TO THAT INSTABILTY
LIMITATION.
ENSUING COLD ADVECTION WILL MAINTAIN LIKELY SHOWER PROBS INTO THE
NIGHT...WITH SNOW SHOWERS POSSIBLE...ESPECIALLY NORTH AND WEST OF
PITTSBURGH AROUND DAYBREAK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
BUILDING HIGH PRESSURE AND DRY ADVECTION SHOULD DRY THE WEATHER
FOR SATURDAY. MOISTURE IS PROJECTED TO THEN INCREASE LATER SUNDAY
INTO MONDAY AS A NORTHERN STREAM TROUGH AND COLD FRONT MOVES EAST
FROM THE GREAT LAKES...WHILE SOUTHERN STREAM LOW PRESSURE DEVELOPS
TOWARD THE MID ATLANTIC STATES. THAT SCENARIO WOULD BRING
INCREASING SHOWER CHANCES FOR THE START OF THE NEW WEEK.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
VFR CONDITIONS WILL PREVAIL WITH HIGH PRESSURE IN PLACE. SW WIND
WITH GUSTS TO 20-25KTS THIS AFTERNOON WILL DIMINISH WITH THE LOSS OF
HEATING THIS EVENING. WITH A STRENGTHENING LOW LEVEL JET...HAVE
INTRODUCED WIND SHEAR AT ALL TAF SITES UNTIL BETTER MIXING OCCURS
AFTER DAYBREAK TOMORROW.
SOME OF THE MODEL GUIDANCE WANTS TO DROP THE STATIONARY FRONT
SOUTHWARD INTO NORTHERN PA TOMORROW. THIS LEADS TO QUITE A DIFFERENT
SOLUTION FOR FORECAST RESTRICTIONS. FOR NOW...HAVE OPTED TO KEEP THE
MORE OPTIMISTIC SOLUTION WHICH HOLD THE MOISTURE AND LOWER CIGS
NORTHWARD...KEEPING VFR CONDITIONS FOR ALL SITES.
.OUTLOOK /WEDNESDAY THROUGH SATURDAY/...
VFR CONDITIONS ARE EXPECTED UNTIL THE APPROACH OF A THURSDAY COLD
FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
920 PM EDT WED MAR 23 2016
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 327 PM EDT WED MAR 23 2016
LOW PRESSURE WILL TRACK ACROSS SOUTHERN LOWER MICHIGAN TONIGHT
AND THURSDAY AND BRING A WIDE RANGE OF WEATHER. UP TO A FOOT OF
SNOW AND SIGNIFICANT ICING IS POSSIBLE ACROSS THE NORTHERN HALF OF
LOWER MICHIGAN. A MIXTURE OF RAIN...SLEET AND FREEZING RAIN IS
EXPECTED ACROSS CENTRAL LOWER MICHIGAN AND RAIN ACROSS THE SOUTH.
THERE COULD BE A FEW THUNDERSTORMS ACROSS FAR SOUTHERN LOWER
MICHIGAN ON THURSDAY. THE STORM WILL BE TAPERING OFF TO SNOW
SHOWERS THURSDAY NIGHT.
&&
.UPDATE...
ISSUED AT 912 PM EDT WED MAR 23 2016
NO HEADLINE OR FCST CHANGES ARE NECESSARY THIS EVENING. A MIX OF
HEAVY WET SNOW AND FREEZING RAIN WILL CONTINUE ACROSS THE WARNING
AREA OVERNIGHT INTO THURSDAY WITH TOTAL ICE ACCUMULATIONS OF A
QUARTER TO HALF AN INCH AND LOCALLY HIGHER AMOUNTS IN EXCESS OF A
HALF AN INCH POSSIBLE.
TOTAL SNOW ACCUMULATIONS OF 5 TO 9 INCHES ARE ANTICIPATED OUR FAR
NORTHERN FCST AREA WHERE PCPN WILL FALL PREDOMINANTLY IN THE FORM
OF SNOW. THE COMBINATION OF HEAVY WET SNOW AND FREEZING RAIN AND
BREEZY CONDITIONS WILL RESULT IN SCATTERED TO POTENTIALLY NUMEROUS
POWER OUTAGES ACROSS PORTIONS OF THE WARNING AREA.
FURTHER SOUTH FOR THE COUNTIES IN THE ADVISORY A MIX OF RAIN AND
FREEZING RAIN WILL CONTINUE THROUGH THE LATE EVENING HOURS THOUGH
PCPN WILL FALL MORE IN THE FORM OF PLAIN RAIN THAN FZRA. EVEN SO
SOME LIGHT ICING IS POSSIBLE PARTICULARLY ACROSS NORTHERN MKG...
KENT... IONIA AND CLINTON COUNTIES.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 327 PM EDT WED MAR 23 2016
NO SIGNIFICANT CHANGES TO THE FORECAST AS THE 12Z MODEL GUIDANCE
REMAINS IN GOOD AGREEMENT AND THE HRRR SUPPORTS THE GOING FORECAST
FOR EVOLUTION OF P TYPE TONIGHT. WE EXPECT THE NORTHERN TIER TO
SEE THE HIGHEST SNOW AMOUNTS WITH WITH A BAND OF SLEET OR FREEZING
RAIN CUTTING SNOW ACCUMULATIONS SHARPLY TO THE SOUTH.
THE ICING THREAT STILL APPEARS TO BE CENTERED AROUND THE AREA
FROM ALMA TO MT PLEASANT AND WEST TO BIG RAPIDS WHERE A QUARTER TO
HALF INCH OF ICE ACCUM IS POSSIBLE. THE SOUTHERN EDGE OF THE
FREEZING RAIN IS STILL EXPECTED TO BE ALONG OR JUST NORTH OF I-96
TONIGHT.
WE ALSO HAVE TO CONTEND WITH THUNDERSTORM POTENTIAL FOR THE
SOUTHERN BORDER OF THE FORECAST AREA ON THURSDAY AS THERE IS SOME
INSTABILITY THAT IS SFC BASED DURING THE AFTERNOON. WILL CONTINUE
TO HAVE THUNDER IN THE FAR SOUTHERN ZONES.
THE LOW MOVES EAST LATE THURSDAY WITH A NORTH FLOW OF COLDER AIR
CHANGING PRECIP OVER TO SNOW SHOWERS DURING THE EVENING ACROSS THE
ENTIRE FORECAST AREA. A QUICK INCH OR TWO OF SNOW IS POSSIBLE
CROSS MUCH OF THE FORECAST AREA DEPENDING ON HOW THE DEFORMATION
ZONE PIVOTS THROUGH. WINDS GUSTING TO 25 MPH COULD CAUSE PROBLEMS
IF ICE ACCUMULATIONS PERSIST INTO THURSDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 327 PM EDT WED MAR 23 2016
HE LONG TERM PORTION OF THE FCST LOOKS LIKE WE WILL SEE MORE
OCCASIONAL WET WEATHER...AS HAS BEEN THE CASE FOR THE PAST FEW WEEKS.
DRIER WEATHER FROM THE END OF THE SHORT TERM ON FRI WILL REMAIN INTO
AT LEAST THE FIRST PART OF SAT BEFORE PCPN CHCS WILL INCREASE LATER.
A SHORT WAVE ROUNDING THE BASE OF A LONGER WAVE TROUGH ACROSS THE
PLAINS WILL LIFT JUST NW OF THE AREA LATE SAT AND SAT NIGHT. THIS
WILL PUSH A FRONT INTO THE AREA. THE FRONT WILL NOT MAKE IT FAR SE
WITH UPPER WAVE STAYING NW. WE WILL ALSO HAVE ANOTHER WAVE FROM THE
SRN JET LIFT OUT OF THE PLAINS AND GO JUST SOUTH OF THE STATE. RAIN
CHCS WILL BE MUCH BETTER ON SUN WITH THE SRN STREAM WAVE AS IT WILL
DRAW GULF MOISTURE NWD. PCPN LOOKS TO BE MAINLY RAIN THROUGH SUN AS
THE COLDER AIR FROM THE NW GETS HELD UP. PCPN COULD EVENTUALLY
CHANGE OVER TO SOME SNOW AT THE END OF THE EVENT AS SOME COLDER AIR
DOES FINALLY TRY TO MAKE IT IN ON THE BACKSIDE OF THE SYSTEM.
WE SHOULD THEN SEE A BREAK IN THE WEATHER FROM LATER MON THROUGH
TUE/TUE NIGHT. THE UPPER PATTERN OVER NORTH AMERICA WILL BE RATHER
AMPLIFIED WITH THE STRONGER SYSTEM EXITING TO THE EAST...AND ANOTHER
LONG WAVE TROUGH SETTING UP ACROSS THE WRN PORTION OF THE COUNTRY.
WE WILL END UP WITH THE UPPER RIDGE HOLDING IN OVER OUR PORTION OF
THE COUNTRY.
THE THREAT FOR PCPN WILL THEN INCREASE ONCE AGAIN AT THE END OF THE
LONG TERM. THE UPPER RIDGE WILL MOVE FAR ENOUGH EAST THAT WAVES
EJECTING FROM THE WRN TROUGH/LOW WILL START TO IMPACT THE AREA
AROUND WED. THIS COULD END UP GETTING PUSHED BACK OVER TIME AS IS
THE CASE MANY TIMES IN THIS TYPE OF A PATTERN.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 825 PM EDT WED MAR 23 2016
IFR CONDITIONS ARE BECOMING MORE WIDESPREAD ACROSS THE AREA AND
THIS TREND WILL CONTINUE. IN FACT BY 12Z...WE SHOULD BE LOOKING AT
WIDESPREAD LIFR CONDITIONS WHICH WILL CONTINUE AT LEAST THROUGH
18Z. THE POOR AVIATION CONDITIONS ARE ASSOCIATED WITH A STRONG LOW
PRESSURE CENTER WHICH WILL PASS OVER THE AREA ON THURSDAY.
THE BULK OF THE PRECIPITATION THE NEXT 24 HOURS...00Z TO
00Z...WILL BE IN THE FORM OF RAIN. HOWEVER...AT KMKG...KGRR AND
KLAN WE ARE LOOKING AT A PERIOD OF LIGHT FREEZING RAIN TONIGHT.
FROM ABOUT 02Z TO 08Z OR SO IT SHOULD BE THE DOMINANT PRECIP
TYPE...ESPECIALLY AT KMKG.
CONDITIONS WILL IMPROVE AS THE LOW PASSES BY THURSDAY LATE
AFTERNOON...AFTER 20Z OR SO.
&&
.MARINE...
ISSUED AT 327 PM EDT WED MAR 23 2016
SMALL CRAFT ADVISORY WILL CONTINUE THROUGH THURSDAY NIGHT.
CONDITIONS SHOULD IMPROVE BY FRIDAY.
&&
.HYDROLOGY...
ISSUED AT 239 PM EDT WED MAR 23 2016
WIDESPREAD PRECIPITATION AMOUNTS OF 0.75-1.50 INCHES ARE EXPECTED
THROUGH FRIDAY MORNING. RIVER RISES WILL OCCUR... BUT NO SIGNIFICANT
FLOODING IS EXPECTED.
MINOR FLOODING IS CERTAINLY POSSIBLE... MAINLY IN THE FORM OF
NUISANCE FLOODING IN LOWLAND AREAS NEAR RIVER BANKS. AS OF THIS
WRITING... RIVER FLOOD ADVISORIES WERE IN EFFECT FOR THE MAPLE
RIVER AT MAPLE RAPIDS... GRAND RIVER AT IONIA... LOOKING GLASS
RIVER AT EAGLE... AND SYCAMORE CREEK AT HOLT.
ADDITIONAL PRECIPITATION IS EXPECTED SUNDAY INTO SUNDAY
NIGHT...WHICH WILL PROLONG ELEVATED RIVER LEVELS AND COULD RESULT IN
ADDITIONAL MINOR FLOODING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THURSDAY FOR MIZ050-
056>059.
WINTER STORM WARNING UNTIL 8 PM EDT THURSDAY FOR MIZ037>040-
043>046-051-052.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EDT FRIDAY FOR LMZ844>849.
&&
$$
UPDATE...LAURENS
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...NJJ
AVIATION...DUKE
HYDROLOGY...EBW
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
826 PM EDT WED MAR 23 2016
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 327 PM EDT WED MAR 23 2016
LOW PRESSURE WILL TRACK ACROSS SOUTHERN LOWER MICHIGAN TONIGHT
AND THURSDAY AND BRING A WIDE RANGE OF WEATHER. UP TO A FOOT OF
SNOW AND SIGNIFICANT ICING IS POSSIBLE ACROSS THE NORTHERN HALF OF
LOWER MICHIGAN. A MIXTURE OF RAIN...SLEET AND FREEZING RAIN IS
EXPECTED ACROSS CENTRAL LOWER MICHIGAN AND RAIN ACROSS THE SOUTH.
THERE COULD BE A FEW THUNDERSTORMS ACROSS FAR SOUTHERN LOWER
MICHIGAN ON THURSDAY. THE STORM WILL BE TAPERING OFF TO SNOW
SHOWERS THURSDAY NIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 327 PM EDT WED MAR 23 2016
NO SIGNIFICANT CHANGES TO THE FORECAST AS THE 12Z MODEL GUIDANCE
REMAINS IN GOOD AGREEMENT AND THE HRRR SUPPORTS THE GOING FORECAST
FOR EVOLUTION OF P TYPE TONIGHT. WE EXPECT THE NORTHERN TIER TO
SEE THE HIGHEST SNOW AMOUNTS WITH WITH A BAND OF SLEET OR FREEZING
RAIN CUTTING SNOW ACCUMULATIONS SHARPLY TO THE SOUTH.
THE ICING THREAT STILL APPEARS TO BE CENTERED AROUND THE AREA
FROM ALMA TO MT PLEASANT AND WEST TO BIG RAPIDS WHERE A QUARTER TO
HALF INCH OF ICE ACCUM IS POSSIBLE. THE SOUTHERN EDGE OF THE
FREEZING RAIN IS STILL EXPECTED TO BE ALONG OR JUST NORTH OF I-96
TONIGHT.
WE ALSO HAVE TO CONTEND WITH THUNDERSTORM POTENTIAL FOR THE
SOUTHERN BORDER OF THE FORECAST AREA ON THURSDAY AS THERE IS SOME
INSTABILITY THAT IS SFC BASED DURING THE AFTERNOON. WILL CONTINUE
TO HAVE THUNDER IN THE FAR SOUTHERN ZONES.
THE LOW MOVES EAST LATE THURSDAY WITH A NORTH FLOW OF COLDER AIR
CHANGING PRECIP OVER TO SNOW SHOWERS DURING THE EVENING ACROSS THE
ENTIRE FORECAST AREA. A QUICK INCH OR TWO OF SNOW IS POSSIBLE
CROSS MUCH OF THE FORECAST AREA DEPENDING ON HOW THE DEFORMATION
ZONE PIVOTS THROUGH. WINDS GUSTING TO 25 MPH COULD CAUSE PROBLEMS
IF ICE ACCUMULATIONS PERSIST INTO THURSDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 327 PM EDT WED MAR 23 2016
HE LONG TERM PORTION OF THE FCST LOOKS LIKE WE WILL SEE MORE
OCCASIONAL WET WEATHER...AS HAS BEEN THE CASE FOR THE PAST FEW WEEKS.
DRIER WEATHER FROM THE END OF THE SHORT TERM ON FRI WILL REMAIN INTO
AT LEAST THE FIRST PART OF SAT BEFORE PCPN CHCS WILL INCREASE LATER.
A SHORT WAVE ROUNDING THE BASE OF A LONGER WAVE TROUGH ACROSS THE
PLAINS WILL LIFT JUST NW OF THE AREA LATE SAT AND SAT NIGHT. THIS
WILL PUSH A FRONT INTO THE AREA. THE FRONT WILL NOT MAKE IT FAR SE
WITH UPPER WAVE STAYING NW. WE WILL ALSO HAVE ANOTHER WAVE FROM THE
SRN JET LIFT OUT OF THE PLAINS AND GO JUST SOUTH OF THE STATE. RAIN
CHCS WILL BE MUCH BETTER ON SUN WITH THE SRN STREAM WAVE AS IT WILL
DRAW GULF MOISTURE NWD. PCPN LOOKS TO BE MAINLY RAIN THROUGH SUN AS
THE COLDER AIR FROM THE NW GETS HELD UP. PCPN COULD EVENTUALLY
CHANGE OVER TO SOME SNOW AT THE END OF THE EVENT AS SOME COLDER AIR
DOES FINALLY TRY TO MAKE IT IN ON THE BACKSIDE OF THE SYSTEM.
WE SHOULD THEN SEE A BREAK IN THE WEATHER FROM LATER MON THROUGH
TUE/TUE NIGHT. THE UPPER PATTERN OVER NORTH AMERICA WILL BE RATHER
AMPLIFIED WITH THE STRONGER SYSTEM EXITING TO THE EAST...AND ANOTHER
LONG WAVE TROUGH SETTING UP ACROSS THE WRN PORTION OF THE COUNTRY.
WE WILL END UP WITH THE UPPER RIDGE HOLDING IN OVER OUR PORTION OF
THE COUNTRY.
THE THREAT FOR PCPN WILL THEN INCREASE ONCE AGAIN AT THE END OF THE
LONG TERM. THE UPPER RIDGE WILL MOVE FAR ENOUGH EAST THAT WAVES
EJECTING FROM THE WRN TROUGH/LOW WILL START TO IMPACT THE AREA
AROUND WED. THIS COULD END UP GETTING PUSHED BACK OVER TIME AS IS
THE CASE MANY TIMES IN THIS TYPE OF A PATTERN.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 825 PM EDT WED MAR 23 2016
IFR CONDITIONS ARE BECOMING MORE WIDESPREAD ACROSS THE AREA AND
THIS TREND WILL CONTINUE. IN FACT BY 12Z...WE SHOULD BE LOOKING AT
WIDESPREAD LIFR CONDITIONS WHICH WILL CONTINUE AT LEAST THROUGH
18Z. THE POOR AVIATION CONDITIONS ARE ASSOCIATED WITH A STRONG LOW
PRESSURE CENTER WHICH WILL PASS OVER THE AREA ON THURSDAY.
THE BULK OF THE PRECIPITATION THE NEXT 24 HOURS...00Z TO
00Z...WILL BE IN THE FORM OF RAIN. HOWEVER...AT KMKG...KGRR AND
KLAN WE ARE LOOKING AT A PERIOD OF LIGHT FREEZING RAIN TONIGHT.
FROM ABOUT 02Z TO 08Z OR SO IT SHOULD BE THE DOMINANT PRECIP
TYPE...ESPECIALLY AT KMKG.
CONDITIONS WILL IMPROVE AS THE LOW PASSES BY THURSDAY LATE
AFTERNOON...AFTER 20Z OR SO.
&&
.MARINE...
ISSUED AT 327 PM EDT WED MAR 23 2016
SMALL CRAFT ADVISORY WILL CONTINUE THROUGH THURSDAY NIGHT.
CONDITIONS SHOULD IMPROVE BY FRIDAY.
&&
.HYDROLOGY...
ISSUED AT 239 PM EDT WED MAR 23 2016
WIDESPREAD PRECIPITATION AMOUNTS OF 0.75-1.50 INCHES ARE EXPECTED
THROUGH FRIDAY MORNING. RIVER RISES WILL OCCUR... BUT NO SIGNIFICANT
FLOODING IS EXPECTED.
MINOR FLOODING IS CERTAINLY POSSIBLE... MAINLY IN THE FORM OF
NUISANCE FLOODING IN LOWLAND AREAS NEAR RIVER BANKS. AS OF THIS
WRITING... RIVER FLOOD ADVISORIES WERE IN EFFECT FOR THE MAPLE
RIVER AT MAPLE RAPIDS... GRAND RIVER AT IONIA... LOOKING GLASS
RIVER AT EAGLE... AND SYCAMORE CREEK AT HOLT.
ADDITIONAL PRECIPITATION IS EXPECTED SUNDAY INTO SUNDAY
NIGHT...WHICH WILL PROLONG ELEVATED RIVER LEVELS AND COULD RESULT IN
ADDITIONAL MINOR FLOODING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THURSDAY FOR MIZ050-
056>059.
WINTER STORM WARNING UNTIL 8 PM EDT THURSDAY FOR MIZ037>040-
043>046-051-052.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EDT FRIDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...NJJ
AVIATION...DUKE
HYDROLOGY...EBW
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
721 PM EDT WED MAR 23 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 528 PM EDT WED MAR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID LEVEL LOW MOVING OUT
OVER WRN KS IN THE SRN STREAM. TO THE N IN THE NRN STREAM...BROAD
TROFFING COVERS MUCH OF CANADA. IN THE CONFLUENCE BTWN THIS NRN
TROFFING AND RIDGING OUT AHEAD OF THE KS LOW...UPPER JET RUNNING
FROM JUST N OF LAKE SUPERIOR TO NRN NEW ENGLAND IS STRENGTHENING.
INCREASING UPPER DIVERGENCE ASSOCIATED WITH THE RIGHT ENTRANCE OF
THE JET IS AIDING PCPN EXPANSION WELL TO THE N OF A NEARLY
STATIONARY SFC FRONT EXTENDING FROM SFC LOW IN NCNTRL KS TO LAKE
ERIE. CLOSER TO HOME...A FEW STRATOCU DEVELOPED IN NE WIND UPSLOPE
AREAS OFF LAKE SUPERIOR EARLIER TODAY. OTHERWISE...HIGH CLOUDS HAVE
BEEN INCREASING AND THICKENING TODAY AFTER MORNING SUNSHINE.
FCST TONIGHT/THU WILL REVOLVE AROUND EVOLUTION OF WINTER STORM
CURRENTLY OVER THE PLAINS. MODELS ARE IN GOOD AGREEMENT SHOWING THE
MID LEVEL LOW OVER KS GRADUALLY TRANSITIONING TO AN OPEN WAVE AS IT
MOVES INTO THE GREAT LAKES REGION LATE THU. MEANWHILE...ASSOCIATED
SFC LOW PRES WILL TRACK FROM NE KS TO SRN LWR MI THU AFTN. INITIAL
BAND OF SNOW CURRENTLY LIFTING TOWARD UPPER MI IS BEING DRIVEN
LARGELY BY AFOREMENTIONED RIGHT ENTRANCE OF UPPER JET AND RESULTING
STRENGTHENING OF LOW/MID LEVEL FGEN AND ISENTROPIC ASCENT. ALTHOUGH
SNOW IS CURRENTLY DEVELOPING/INTENSIFYING WHILE SLOWLY LIFTING N THRU
WI...IT WILL ENCOUNTER VERY DRY AIR AT THE LOWER LEVELS THAT WILL
CONTINUE TO ADVECT S AND W FROM HIGH PRES OVER ONTARIO. SFC DWPTS
HAVE BEEN DOWN INTO THE SINGLE DIGITS ACROSS PORTIONS OF UPPER MI
THIS AFTN AND ARE IN THE NEGATIVE SINGLE DIGITS IN ONTARIO. WITH ONLY
A SLIGHT NORTHWARD SHIFT OF FGEN/ISENTROPIC ASCENT TONIGHT... THE
APPROACHING SNOW IN WI WILL INCREASINGLY STRUGGLE TO MOVE N INTO
UPPER MI AS ADVECTION OF LOW-LEVEL DRY AIR ERODES THE NRN PORTION OF
THE PCPN SHIELD. ALL AVBL HIGH RES MODEL GUIDANCE...INCLUDING HOURLY
RAP RUNS TODAY AND 18Z NAM...SHOW PCPN HAVING TROUBLE LIFTING MUCH
FARTHER THAN FAR SCNTRL UPPER MI TONIGHT WITH NORTHWARD EXTENT FROM
ROUGHLY JUST N OF IRON MOUNTAIN TO JUST N OF MANSTIQUE BY 12Z THU.
DURING THU MORNING...DEFORMATION SNOW SHIELD...WHICH IS CURRENTLY
PRODUCING CONSIDERABLE LIGHTNING/TSSN ACROSS PORTIONS OF
NEBRASKA...WILL SHIFT INTO THE UPPER GREAT LAKES IN A WEAKENING
STATE. AS THIS OCCURS...SNOW SHOULD EXPAND INTO PORTIONS OF NCTNRL
AND NE UPPER MI. SNOW WILL THEN DIMINISH/END STEADILY FROM W TO E
DURING THE AFTN.
FOR THIS EVENT...DO NOT EXPECT ANY SNOW TO FALL FROM IRONWOOD TO
L`ANSE INTO THE KEWEENAW. IT`S QUESTIONABLE WHETHER ANY SNOW WILL
REACH MARQUETTE. TO THE S AND E...EXPECT A SIGNIFICANT GRADIENT OF
SNOWFALL FROM N TO S WITH WITH AMOUNTS RANGING FROM AROUND 1 INCH
NEAR LAKE SUPERIOR TO ABOUT A FOOT IN THE CITY OF MENOMINEE. THE NRN
EDGE OF THE SNOW WILL BE THE MOST DIFFICULT CHALLENGE AS DRY AIR
CONTNUALLY EATS AWAY AT SNOW LIFTING INTO THE AREA UNDER WEAKENING
FORCING. WOULD NOT BE SURPRISED IF THE NRN EXTENT OF SNOWFALL
REFLECTED IN THIS FCST DOES NOT OCCUR. HAVE ADDED DICKINSON/NRN
SCHOOLCRAFT/LUCE COUNTIES TO ADVY...THOUGH IT WILL ONLY BE THE SRN
PARTS OF THOSE COUNTIES THAT WILL REACH THE LOW SLR ADVY CRITERIA OF
AT LEAST 2-4 INCHES OF SNOW ACCUMULATION. FAR SRN PARTS OF DELTA AND
SCHOOLCRAFT COUNTIES MAY SEE STORM TOTAL SNOW UP AROUND 6 INCHES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 516 PM EDT WED MAR 23 2016
MODELS WERE IN GENERAL AGREEMENT THAT TROUGHING OVER THE CNTRL CONUS
WITH THE NRN STREAM DOMINATING THE NRN LAKES...WILL GIVE WAY TO MID
LEVEL RIDGING AS A SRN STREAM TROUGH DIGS INTO THE GREAT BASIN.
THURSDAY NIGHT...AS THE STRONG SHRTWAVE TROUGH LIFT QUICKLY TO THE
NE THROUGH LOWER MI DURING THE EVENING STRONG 700-300 MB QVECTOR DIV
MOVING INTO THE ERN CWA WILL END THE LINGERING SNOW WITH LITTLE
ADDITIONAL ACCUMULATIONS. MID LEVEL AND SFC RIDGING BUILDING INTO
THE AREA OVERNIGHT WILL BRING CLEARING SKIES AND GOOD RADIATIONAL
COOLING CONDITIONS FAVORING TEMPS NEAR THE LOWER END OF
GUIDANCE...ESPECIALLY INLAND WEST HALF.
FRIDAY...SRLY FLOW AND WAA WILL DEVELOP AS THE RIDGE DEPARTS TO THE
EAST. SUNSHINE WILL ALLOW TEMPS TO CLIMB NEAR OR ABOVE SEASONAL
AVERAGES WITH HIGHS IN THE UPER 30S N AND E TO HE LOWER TO MID 40S
OVER THE SW.
FRI NIGHT THROUGH SAT NIGHT...MODELS SHOW PCPN ASSOCIATED WITH MID
LEVEL SHORTWAVE AND SFC TROUGH SPREADING ACROSS UPPER MICHIGAN. WITH
ONLY MODEST DYNAMICS AND MOISTURE INFLOW...GENERALLY LIGHT AMOUNTS
OF AROUND 0.10 INCH OR LESS IS EXPECTED. FCST LOW LEVEL THICKNESS
AND WET-BULB ZERO HEIGHTS SUGGEST THAT THE PCPN MAY FALL AS
RAIN...ESPECIALLY OVER THE SOUTH AND EAST DURING PEAK HEATING
SATURDAY.
SUN-MON...WITH SFC RIDGING AND A DRY AIRMASS OVER THE AREA...EXPECT
LITTLE PCPN DESPITE POTENTIAL FOR WEAK NRN STREAM SHRTWVS TO BRUSH
THE AREA. TEMPS SHOULD REMAIN NEAR SEASONAL AVERAGES.
TUE-WED...MILDER AIR IS EXPECTED TO SPREAD INTO THE REGION WITH A
STRENGTHENING WAA PATTERN AHEAD OF A TROUGH DEVELOPING OVER THE ERN
PLAINS. SOME LIGHT PCPN...MAINLY AS RAIN...MAY SPREAD TOWARD THE
AREA BY WED AS MOISTURE ADVECTION ALSO INCREASES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 721 PM EDT WED MAR 23 2016
BEING WELL N OF A WINTER STORM THAT WILL BE TRACKING INTO THE GREAT
LAKES REGION...KIWD/KCMX WILL REMAIN VFR THRU THE FCST PERIOD UNDER
AN E TO NE FEED OF DRY AIR AT THE LOW LEVELS. THE NRN FRINGE OF SNOW
ASSOCIATED WITH THE STORM SYSTEM MAY BRUSH KSAW THU MORNING. IF
SO...VFR CONDITIONS MAY FALL TO HIGH END MVFR AT THAT TIME.
OTHERWISE...VFR CONDITIONS WILL PREVAIL AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 528 PM EDT WED MAR 23 2016
E TO NE WINDS UP TO 25 TO 30KT ARE EXPECTED TONIGHT INTO THU AS PRES
GRADIENT TIGHTENS OVER THE UPPER LAKES BETWEEN HIGH PRES DRIFTING
ACROSS ONTARIO INTO QUEBEC AND LOW PRES TRACKING FROM THE CENTRAL
PLAINS TO FAR SOUTHERN ONTARIO BY LATE THU EVENING. WINDS WILL
QUICKLY DIMINISH TO 15KT OR LESS FROM W TO E LATE THU AFTN THRU FRI
MORNING AS A HIGH PRES RIDGE ARRIVES. THERE WILL BE SOME INCREASE IN
WINDS LATER FRI INTO SAT AHEAD OF THE NEXT LOW PRES TROF. SOUTHERLY
WINDS OVER THE E HALF OF LAKE SUPERIOR MAY INCREASE INTO THE 15-25KT
RANGE FOR A TIME AHEAD OF THE TROF FRI NIGHT INTO SAT. LIKEWISE...
THERE MAY BE 15-25KT NW WINDS FOR A TIME IN THE WAKE OF THE TROF
PASSAGE LATE SAT/SAT NIGHT. WINDS WILL BECOME LIGHT AGAIN LATER SUN
AS A HIGH PRES RIDGE ARRIVES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 6 AM TO 5 PM EDT THURSDAY FOR
MIZ007-014-085.
WINTER WEATHER ADVISORY FROM 11 PM THIS EVENING TO 2 PM EDT
THURSDAY FOR MIZ013.
WINTER STORM WARNING UNTIL 1 PM CDT THURSDAY FOR MIZ012.
WINTER WEATHER ADVISORY FROM 1 AM TO 1 PM CDT THURSDAY FOR
MIZ011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WARNING UNTIL 5 PM EDT THURSDAY FOR LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
432 PM EDT TUE MAR 22 2016
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 432 PM EDT TUE MAR 22 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW WNW FLOW ACROSS THE UPPER
GREAT LAKES BTWN TROFFING OVER ERN CANADA AND LOW AMPLITUDE RIDGING
SHIFTING OUT OVER THE PLAINS. PLAINS RIDGING IS OUT AHEAD OF A TROF
MOVING ACROSS THE WRN CONUS. ENERGY OVER SRN NV IN THE BASE OF THAT
TROF WILL SPIN UP A WINTER STORM THAT WILL TRACK ACROSS THE GREAT
LAKES REGION WED NIGHT NIGHT/THU. CLOSER TO HOME...STREAK OF -SN IN
WAA/ISENTROPIC ASCENT REGIME AND AIDED BY SHARPER FGEN HAS
DIMINISHED ACROSS THE FCST AREA AFTER LEAVING A DUSTING TO AROUND 2
INCHES OF SNOW.
LATEST RADAR IMAGERY SHOWS BACK EDGE OF DIMINISHING LIGHT PCPN
EXITING NE MN. FCST SOUNDINGS SHOW RATHER PRONOUNCED DRYING FROM THE
N AND E THIS EVENING AS SFC HIGH PRES BUILDS ACROSS MANITOBA INTO
NRN ONTARIO TONIGHT. 12Z CYPL SOUNDING AND VIS SATELLITE IMAGERY
TODAY SUPPORTS THIS DRYING TREND AS CLEAR SKIES DOMINATE NRN ONTARIO
WITH ONLY MID/HIGH CLOUDS ACROSS NE LAKE SUPERIOR. WILL THUS CARRY A
MENTION OF -SN INTO EARLY THIS EVENING THEN END PCPN WNW TO ESE AS
FORCING EXITS AND DRIER AIR ARRIVES. EVEN IF LOW CLOUDS DO SCATTER
OUT OR CLEAR OUT...NORTHEASTERLY FLOW OFF LAKE SUPERIOR UNDER 850MB
TEMPS -9/-10C MAY SUPPORT STRATOCU EXPANSION LATE TONIGHT AND/OR WED
MORNING. DEPENDING ON DEGREE OF CLEARING...TEMPS MAY FALL INTO THE
TEENS AT SOME INTERIOR LOCATIONS.
ON WED...SHORTWAVE OVER SRN NV WILL EMERGE OUT OVER THE WRN PLAINS
AS A CLOSED MID LEVEL LOW WHILE THE ASSOCIATED SFC LOW ORGANIZES
OVER KS. DOWNSTREAM...TIGHTENING CONFLUENCE ZONE BTWN SRN STREAM
RIDGING AHEAD OF THE WRN PLAINS TROF AND CONTINUED NRN STREAM
TROFFING OVER ERN CANADA WILL RESULT IN A STRENGTHENING UPPER JET
FROM NRN ONTARIO/LAKE SUPERIOR EASTWARD. UPPER DIVERGENCE ASSOCIATED
WITH THE RIGHT ENTRANCE OF THE JET WILL HELP PCPN EXPAND TO THE N OF
A NEARLY STATIONARY SFC FRONT EXTENDING FROM THE SFC LOW TO LAKE
ERIE. GIVEN THE ADVECTION OF LOW-LEVEL DRY AIR ASSOCIATED WITH SFC
HIGH PRES SETTLING OVER NRN ONTARIO ON WED AND THE MAIN FGEN ZONE S
OF THE AREA...WILL LEAN TOWARD A SLOWER NORTHWARD EXPANSION OF PCPN
INTO FAR SCNTRL UPPER MI WED AFTN. FCST WILL SHOW SCHC POPS
SPREADING INTO MENOMINEE COUNTY DURING THE AFTN...BUT
LIKELY/CATEGORICAL POPS HOLDING OFF UNTIL 22-23Z OVER THE SRN HALF
OF THE COUNTY. CHC POPS WILL EXTEND AS FAR N AS KIMT/KESC AT 23Z.
ACROSS THE REST OF THE AREA...OUTSIDE OF ANY MORNING STRATOCU THAT
MAY DEVELOP OVER THE W AND NCNTRL...EXPECT A GRADUAL THICKENING OF
HIGH CLOUDS. ALTHOUGH HIGH TEMPS WILL REACH THE LOW/MID 30S...A
STEADY NE WIND WILL ADD A CHILL...ESPECIALLY IN MENOMINEE COUNTY
WHERE COASTAL CONVERGENCE/FUNNELING DOWN THE BAY WILL ENHANCE WINDS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 344 PM EDT TUE MAR 22 2016
...FOCUS IS ON GREAT LAKES STORM LATE WED AFTN INTO THU MORNING...
UPPER TROUGH OVER WESTERN CONUS TO ROCKIES MOVES ACROSS SOUTHERN
PLAINS ON WED MORNING THEN LIFTS TO WESTERN GREAT LAKES ON THU AND
OVER LOWER GREAT LAKES ON FRI. TROUGH ALOFT MAINTAINS POSITIVE OR
NEUTRAL TILT AS STRONGEST JET ENERGY REMAINS AHEAD OF TROUGH. SFC
LOW 987MB-991MB DEEPENS OVER KS THROUGH MIDDAY WED THEN MOVES TO
NORTHEAST KS/NORTHWEST MO BY WED EVENING. FRONT THAT MOVES SOUTH
ACROSS UPPER GREAT LAKES INTO TONIGHT SHOULD BE VCNTY OF SOUTHERN
IOWA TO SOUTH OF CHICAGO AND INTO FAR SOUTHERN LOWER MI BY WED
EVENING. SHARP H85 FRONT WILL BE NORTH OF THE SFC FRONT...VCNTY OF
SOUTHERN MN TO CNTRL WI AND CNTRL LOWER MICHIGAN. EXPECT BAND OF
SNOW TO STREAK AHEAD OF THE SFC LOW ALONG THE H85 FRONT AND WITHIN
REGION OF H85-H7 FRONTOGENEIS. AS THE UPPER TROUGH DRAWS CLOSER LATE
WED AFTN INTO WED NIGHT...FARTHER NORTH H85 TROUGH MAY PUSH THE
INITIAL FGEN SNOW OVER FAR SOUTHERN UPR MICHIGAN. OTHERWISE...NE
WINDS TO NORTH OF THE FGEN CIRCULATION WILL BE ADVECTING DRY AIR
OVER UPR MICHIGAN FM LARGE HIGH OVER ONTARIO AND QUEBEC...ULTIMATELY
HELPING TO SLOW NORTHWARD PROGRESS OF SYSTEM SNOW.
UPPER TROUGH AXIS LIFTS ACROSS WESTERN GREAT LAKES WED NIGHT INTO
THU. SOME INIDIATION THAT WEAKER SHORTWAVE TROUGH DIGS INTO THE
WEST SIDE OF THE UPPER TROUGH...WHICH MAY BRING HEAVIER SNOW FARTHER
NORTH. DEFORMATION AND PVA NORTHERN PORTION OF THE UPPER TROUGH AXIS
WILL SUPPORT INCREASED SNOW FM NORTHEAST WI INTO AT LEAST SCNTRL UPR
MICHIGAN. H85 TEMPS -8C OR LOWER INDICATE LAKE ENHANCEMENT WILL
OCCUR WHERE THE LARGE SCALE SNOW IS FALLING. THE MAIN QUESTION THAT
REMAINS WITH THIS STORM SYSTEM IS HOW FAR NORTH WILL SECONDARY SURGE
OF SNOW TRACK ON WED NIGHT INTO THU MORNING. SCNTRL UPR MICHIGAN IS
STILL SHOWN TO BE ON THE NORTHERN FRINGE OF HEAVIER SYNOPTIC SNOW
WITH QPF AMOUNTS OVER 0.60 INCHES AT LEAST FOR MNM...BUT LATEST
TRENDS FOR NAM/GFS AND GEM SHOW LESS QPF OVER NORTHERN UPR MICHIGAN
AS THEY TRENDED SLIGHTLY SOUTH WITH UPPER TROUGH AXIS AND POSITION
OF SFC LOW. NOW IF THE SYNOPTIC SNOW IS FARTHER NORTH THAN MODEL
CONSENSUS INDICATES ATTM...THEN GOING WATCHES WOULD HAVE TO BE
EXPANDED NORTH FOR HEAVIER SYNOPTIC SNOW AND ALSO WOULD HAVE HEAVIER
SNOW FOR HIGHER TERRAIN NEAR LK SUPERIOR NORTH CENTRAL WITH
FAVORABLE NE UPSLOPE FLOW AND LAKE ENHANCEMENT. VOLITILITY OF THE
MODEL SOLUTION SHOWS UP IN SREF MEMBERS WHICH SHOW LEAST SPREAD AT
KMNM /MIN OF 4 INCHES AND MAX OF 12 INCHES/ WHILE JUST NORTH OF
THERE AT KIMT/KESC AND KMQT...SPREAD RANGES FM LESS THAN 2 INCHES TO
OVER 10 INCHES.
WILL KEEP MENOMINEE IN WINTER STORM WATCH AS MAJORITY OF HEAVIER
SNOW WOULD NOT MOVE IN UNTIL WED NIGHT. NE WINDS OFF THE BAY OF
GREEN BAY WITH H85 TEMPS AROUND -8C WOULD BE GOOD ENOUGH FOR LAKE
ENHANCEMENT. EVEN WITH THE WET SNOW...EXPOSURE TO NE WINDS OFF OF
THE BAY...OVER 35 KTS IN THE MIXED LAYER...WILL ALSO RESULT IN
BLSN/LOW VSBY ISSUES IF WIDESPREAD AND HEAVY SNOW AFFECTS THE AREA.
GIVEN UNCERTAINTY OF NORTHERN EDGE OF SYSTEM SNOW...DID NOT ADD ANY
OTHER PARTS OF UPR MICHIGAN INTO WATCH...THOUGH AT THE LEAST COULD
SEE NEED FOR EVENTUAL ADVISORY FOR REST OF SCNTRL AND SOUTHEAST CWA.
REST OF EXTENDED...DECENT AGREEMENT THAT SFC LOW TRACKS OVER LOWER
MICHIGAN TO SOUTHERN LK HURON BY THU EVENING. N TO NE WINDS ARE
CYCLONIC IN WAKE OF THE LOW ACROSS LK SUPERIOR BUT H85 TEMPS DOWN TO
-10C ARE NOT LOW ENOUGH FOR LAKE EFFECT. EXPECT COLDEST TEMPS IN THE
SINGLE DIGITS ON THU NIGHT OVER INTERIOR WEST. MOST OF FRI SHOULD BE
DRY WITH TEMPS PUSHING BACK TO AROUND NORMAL. TEMPS GRADUALLY COOL
THROUGH WEEKEND AS TROUGH CROSSES REGION. BEST CHANCE OF SNOW WITH
THIS FEATURE IS LATE SAT INTO SAT NIGHT. MAY SEE MIX OF RAIN/SNOW
SAT AFTN INTO SAT EVENING OVER THE SOUTH. LOOKS MAINLY DRY EASTER
INTO MON. STORM EARLIER ECMWF RUN SHOWED IS FARTHER EAST ACROSS THE
LOWER GREAT LAKES/OHIO VALLEY. SUPPOSE IT COULD COME BACK WEST...BUT
RIGHT NOW SOLUTION IS TOO FAR EAST TO AFFECT UPPER GREAT LAKES. HIGH
PRESSURE SHOULD BRING MAINLY DRY WEATHER INTO EARLY NEXT WEEK...BUT
TEMPS WILL STAY AT OR BLO NORMAL AS THE COOLER WEATHER PATTERN THAT
SETTLED IN LATE LAST WEEK PERSISTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 141 PM EDT TUE MAR 22 2016
AS -SN DIMINISHES/ENDS THIS AFTN AND DRIER AIR GRADUALLY ARRIVES
FROM THE N AND E THRU TONIGHT...OCNL TO PREVAILING IFR CONDITIONS AT
KCMX/KSAW WILL IMPROVE TO MVFR THIS AFTN/EARLY EVENING THEN TO VFR
DURING THE EVENING...BEGINNING FIRST AT KCMX. AT KIWD...MVFR CIGS
WILL IMPROVE TO VFR LATER TONIGHT. WITH A COOL AIR MASS AND UPSLOPE
FLOW OFF LAKE SUPERIOR...MVFR CIGS MAY REDEVELOP FOR A TIME EARLY
WED MORNING AT ALL TERMINALS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 432 PM EDT TUE MAR 22 2016
NE WINDS ARE EXPECTED THROUGH THU AS SFC HIGH PRES DRIFTS ACROSS
NORTHERN ONTARIO WHILE LOW PRESSURE TRACKS FROM THE CENTRAL PLAINS
ACROSS THE SOUTHERN GREAT LAKES. TONIGHT/WED SHOULD FEATURE MOSTLY
15-25KT WINDS OVER THE W HALF OF LAKE SUPERIOR...STRONGEST OVER THE
FAR W DUE TO COASTAL CONVERGENCE/FUNNELING...AND 10-20KT WINDS OVER
THE E HALF. WINDS WILL THEN INCREASE TO 20-30KT WED NIGHT/THU AS THE
LOW PRES TRACKS THRU THE SOUTHERN GREAT LAKES. MIGHT SEE A FEW GALE
FORCE GUSTS OVER THE E ON THU. WINDS WILL THEN DIMINISH THRU THU
NIGHT AS A HIGH PRES RIDGE PASSES. WINDS WILL INCREASE SOME ON FRI
AHEAD OF THE NEXT LOW PRES TROF WHICH WILL PASS ACROSS LAKE SUPERIOR
ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON FOR MIZ012.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON FOR
LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
347 PM EDT TUE MAR 22 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM EDT TUE MAR 22 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW WNW FLOW ALOFT
OVER THE GREAT LKS BTWN GENERAL TROFFING OVER ERN CANADA/NE CONUS AND
AN UPR RDG OVER THE ROCKIES. THERE IS A GOOD DEAL OF MID/HI CLDS
STREAMING INTO THE AREA DOWNSTREAM OF A SHRTWV MOVING THRU THE NRN
PLAINS/ACCOMPANYING WAA...BUT VERY DRY LLVL AIR SHOWN ON THE 00Z INL
RAOB HAS SLOWED/LIMITED DEVELOPMENT OF BAND OF WAA PCPN STRETCHING
ACRS NCENTRAL MN TOWARD FAR WRN LK SUP DESPITE A FAIRLY TIGHT PRES
GRADIENT SHOWN BEST ON THE 285-290K ISENTROPIC SFCS /H85-7/ OVER THE
AREA AND ACCOMPANYING BAND OF SHARPER FGEN. THIS VERY DRY AIR IS
EVIDENT ALSO ON THE 00Z YPL/GRB/APX RAOBS AND HAS ALLOWED NOTHING
MORE THAN SOME FLURRIES INTO THE CWA AS OF 08Z DESITE THE THICKENING
CLDS/SHARPENING FGEN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/SN AMOUNTS
ASSOCIATED WITH WAA/FGEN FCST TO IMPACT THE CWA AHEAD OF SHRTWV NOW
MOVING THRU THE NRN PLAINS.
TODAY...SHRTWV MOVING THRU THE NRN PLAINS IS FCST TO SHEAR OUT AS IT
HEADS TO THE E IN FAST WNW FLOW ALOFT. ALTHOUGH THIS TREND AND
ABUNDANT DRY AIR ARE NOT FAVORABLE FOR PCPN...MODELS SHOW PRES
GRADIENT ON THE 285-290K ISENTROPIC SFC TIGHTENING OVER THE CWA AS
AXIS OF SHARPER FGEN IN THE H85-75 LYR CROSSES THE AREA THIS MRNG
BEFORE EXITING IN THE AFTN. SINCE THE PRES/THERMAL GRADIENT IS FCST
TO TIGHTEN...EXPECT SHORT TERM MODELS ARE ON THE RIGHT TRACK SHOWING
BAND OF SOME -SN DVLPG OVER MAINLY THE CNTRL CWA...WHICH WL BE UNDER
THE BAND OF SHARPER FGEN. FCST SPECIFIC HUMIDITY IN THE 2-3G/KG
RANGE WOULD SUPPORT UP TO ABOUT 3 INCHES OF SN DURING THE 6-9HR
PERIOD OF FORCING...BUT IMPACT OF LLVL DRY AIR AS WELL AS MARGINAL
ADDITIONAL DYANMIC SUPPORT RELATED TO THE SHEARING SHRTWV SUGGEST SN
TOTALS WL BE MAINLY UP TO 2 INCHES. IN FACT...THE WPC FCST SHOWS
ONLY 1 TO 2 INCHES OF SN UNDER THE FGEN BAND. THE ONE EXCEPTION MAY
BE OVER THE HIER TERRAIN OF THE NCENTRAL...WHERE UPSLOPING ENE WINDS
MAY AID LLVL MOISTENING/SN AMOUNTS. OVER THE FAR SCENTRAL... FCST
SDNGS SUG ANY PCPN WL BE AT LEAST MIXED WITH RA. BUT MANY OF THE
MODELS SHOW NO PCPN FALLING IN THIS AREA ANYWAY...SO WL PAINT THE
LOWER POPS IN THIS AREA. ONE OTHER IMPACT OF THE LLVL DRY AIR WL TO
SHARPEN THE NRN EDGE OF THE POPS SO THAT THE NRN KEWEENAW MAY SEE
LTL PCPN/SN AS WELL. AFTER THE SHARPER FGEN EXITS THIS AFTN...EXPECT
DIMINISHING POPS. PREVIOUS FCSTS HAVE SHOWN THE PCPN MAY TAPER TO
DRIZZLE...BUT CONCERNED THE DRYNESS OF THE LLVLS MAY LIMIT THIS
POTENTIAL. CONFINED THE MENTION OF DRIZZLE TO MAINLY THE HIER
TERRAIN OF THE NCENTRAL.
TNGT...WITH DEEP LYR QVECTOR DVGC/MID LVL DRYING DOMINATING...EXPECT
A GENERALLY DRY FCST. SOME OF THE MODELS SHOW SOME LGT PCPN
PERSISTING OVER THE HIER TERRAIN OF THE NCENTRAL WITH UPSLOPE NNE
FLOW ON THE SRN FLANK OF HI PRES BLDG INTO NW ONTARIO...BUT DRYNESS
OF THE AIRMASS TO THE N FAVORS THE DRIER PCPN FREE GUIDANCE FOR THIS
AREA. BUT WL HOLD ON TO SOME LO CHC POPS FOR SN OVER THE FAR
SCENTRAL...WHICH WL BE NEAR THE NRN EDGE OF THE PCPN SHIELD
ASSOCIATED WITH WAVES OF LO PRES MOVING ALONG STALLED SFC FNT OVER
THE LOWER GRT LKS. DEPENDING ON THE DEGREE OF CLRG ASSOCIATED WITH
THE INFLUX OF DRIER AIR FM THE N...TEMPS MAY FALL INTO THE TEENS AT
SOME OF THE COLDER SPOTS DURING THE NGT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 344 PM EDT TUE MAR 22 2016
...FOCUS IS ON GREAT LAKES STORM LATE WED AFTN INTO THU MORNING...
UPPER TROUGH OVER WESTERN CONUS TO ROCKIES MOVES ACROSS SOUTHERN
PLAINS ON WED MORNING THEN LIFTS TO WESTERN GREAT LAKES ON THU AND
OVER LOWER GREAT LAKES ON FRI. TROUGH ALOFT MAINTAINS POSITIVE OR
NEUTRAL TILT AS STRONGEST JET ENERGY REMAINS AHEAD OF TROUGH. SFC
LOW 987MB-991MB DEEPENS OVER KS THROUGH MIDDAY WED THEN MOVES TO
NORTHEAST KS/NORTHWEST MO BY WED EVENING. FRONT THAT MOVES SOUTH
ACROSS UPPER GREAT LAKES INTO TONIGHT SHOULD BE VCNTY OF SOUTHERN
IOWA TO SOUTH OF CHICAGO AND INTO FAR SOUTHERN LOWER MI BY WED
EVENING. SHARP H85 FRONT WILL BE NORTH OF THE SFC FRONT...VCNTY OF
SOUTHERN MN TO CNTRL WI AND CNTRL LOWER MICHIGAN. EXPECT BAND OF
SNOW TO STREAK AHEAD OF THE SFC LOW ALONG THE H85 FRONT AND WITHIN
REGION OF H85-H7 FRONTOGENEIS. AS THE UPPER TROUGH DRAWS CLOSER LATE
WED AFTN INTO WED NIGHT...FARTHER NORTH H85 TROUGH MAY PUSH THE
INITIAL FGEN SNOW OVER FAR SOUTHERN UPR MICHIGAN. OTHERWISE...NE
WINDS TO NORTH OF THE FGEN CIRCULATION WILL BE ADVECTING DRY AIR
OVER UPR MICHIGAN FM LARGE HIGH OVER ONTARIO AND QUEBEC...ULTIMATELY
HELPING TO SLOW NORTHWARD PROGRESS OF SYSTEM SNOW.
UPPER TROUGH AXIS LIFTS ACROSS WESTERN GREAT LAKES WED NIGHT INTO
THU. SOME INIDIATION THAT WEAKER SHORTWAVE TROUGH DIGS INTO THE
WEST SIDE OF THE UPPER TROUGH...WHICH MAY BRING HEAVIER SNOW FARTHER
NORTH. DEFORMATION AND PVA NORTHERN PORTION OF THE UPPER TROUGH AXIS
WILL SUPPORT INCREASED SNOW FM NORTHEAST WI INTO AT LEAST SCNTRL UPR
MICHIGAN. H85 TEMPS -8C OR LOWER INDICATE LAKE ENHANCEMENT WILL
OCCUR WHERE THE LARGE SCALE SNOW IS FALLING. THE MAIN QUESTION THAT
REMAINS WITH THIS STORM SYSTEM IS HOW FAR NORTH WILL SECONDARY SURGE
OF SNOW TRACK ON WED NIGHT INTO THU MORNING. SCNTRL UPR MICHIGAN IS
STILL SHOWN TO BE ON THE NORTHERN FRINGE OF HEAVIER SYNOPTIC SNOW
WITH QPF AMOUNTS OVER 0.60 INCHES AT LEAST FOR MNM...BUT LATEST
TRENDS FOR NAM/GFS AND GEM SHOW LESS QPF OVER NORTHERN UPR MICHIGAN
AS THEY TRENDED SLIGHTLY SOUTH WITH UPPER TROUGH AXIS AND POSITION
OF SFC LOW. NOW IF THE SYNOPTIC SNOW IS FARTHER NORTH THAN MODEL
CONSENSUS INDICATES ATTM...THEN GOING WATCHES WOULD HAVE TO BE
EXPANDED NORTH FOR HEAVIER SYNOPTIC SNOW AND ALSO WOULD HAVE HEAVIER
SNOW FOR HIGHER TERRAIN NEAR LK SUPERIOR NORTH CENTRAL WITH
FAVORABLE NE UPSLOPE FLOW AND LAKE ENHANCEMENT. VOLITILITY OF THE
MODEL SOLUTION SHOWS UP IN SREF MEMBERS WHICH SHOW LEAST SPREAD AT
KMNM /MIN OF 4 INCHES AND MAX OF 12 INCHES/ WHILE JUST NORTH OF
THERE AT KIMT/KESC AND KMQT...SPREAD RANGES FM LESS THAN 2 INCHES TO
OVER 10 INCHES.
WILL KEEP MENOMINEE IN WINTER STORM WATCH AS MAJORITY OF HEAVIER
SNOW WOULD NOT MOVE IN UNTIL WED NIGHT. NE WINDS OFF THE BAY OF
GREEN BAY WITH H85 TEMPS AROUND -8C WOULD BE GOOD ENOUGH FOR LAKE
ENHANCEMENT. EVEN WITH THE WET SNOW...EXPOSURE TO NE WINDS OFF OF
THE BAY...OVER 35 KTS IN THE MIXED LAYER...WILL ALSO RESULT IN
BLSN/LOW VSBY ISSUES IF WIDESPREAD AND HEAVY SNOW AFFECTS THE AREA.
GIVEN UNCERTAINTY OF NORTHERN EDGE OF SYSTEM SNOW...DID NOT ADD ANY
OTHER PARTS OF UPR MICHIGAN INTO WATCH...THOUGH AT THE LEAST COULD
SEE NEED FOR EVENTUAL ADVISORY FOR REST OF SCNTRL AND SOUTHEAST CWA.
REST OF EXTENDED...DECENT AGREEMENT THAT SFC LOW TRACKS OVER LOWER
MICHIGAN TO SOUTHERN LK HURON BY THU EVENING. N TO NE WINDS ARE
CYCLONIC IN WAKE OF THE LOW ACROSS LK SUPERIOR BUT H85 TEMPS DOWN TO
-10C ARE NOT LOW ENOUGH FOR LAKE EFFECT. EXPECT COLDEST TEMPS IN THE
SINGLE DIGITS ON THU NIGHT OVER INTERIOR WEST. MOST OF FRI SHOULD BE
DRY WITH TEMPS PUSHING BACK TO AROUND NORMAL. TEMPS GRADUALLY COOL
THROUGH WEEKEND AS TROUGH CROSSES REGION. BEST CHANCE OF SNOW WITH
THIS FEATURE IS LATE SAT INTO SAT NIGHT. MAY SEE MIX OF RAIN/SNOW
SAT AFTN INTO SAT EVENING OVER THE SOUTH. LOOKS MAINLY DRY EASTER
INTO MON. STORM EARLIER ECMWF RUN SHOWED IS FARTHER EAST ACROSS THE
LOWER GREAT LAKES/OHIO VALLEY. SUPPOSE IT COULD COME BACK WEST...BUT
RIGHT NOW SOLUTION IS TOO FAR EAST TO AFFECT UPPER GREAT LAKES. HIGH
PRESSURE SHOULD BRING MAINLY DRY WEATHER INTO EARLY NEXT WEEK...BUT
TEMPS WILL STAY AT OR BLO NORMAL AS THE COOLER WEATHER PATTERN THAT
SETTLED IN LATE LAST WEEK PERSISTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 141 PM EDT TUE MAR 22 2016
AS -SN DIMINISHES/ENDS THIS AFTN AND DRIER AIR GRADUALLY ARRIVES
FROM THE N AND E THRU TONIGHT...OCNL TO PREVAILING IFR CONDITIONS AT
KCMX/KSAW WILL IMPROVE TO MVFR THIS AFTN/EARLY EVENING THEN TO VFR
DURING THE EVENING...BEGINNING FIRST AT KCMX. AT KIWD...MVFR CIGS
WILL IMPROVE TO VFR LATER TONIGHT. WITH A COOL AIR MASS AND UPSLOPE
FLOW OFF LAKE SUPERIOR...MVFR CIGS MAY REDEVELOP FOR A TIME EARLY
WED MORNING AT ALL TERMINALS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EDT TUE MAR 22 2016
AN EXTENDED PERIOD OF NE WINDS ARE EXPECTED THROUGH THU AS RIDGING
SETTLES OVER NORTHERN ONTARIO AND A STRONG LOW PRESSURE SYSTEM
TRACKS FROM THE CENTRAL PLAINS ACROSS THE SOUTHERN GREAT LAKES.
WINDS TO 25 KNOTS ARE EXPECTED ACROSS WESTERN LAKE SUPERIOR TODAY.
WINDS BECOME 20 TO 30 KNOTS FOR ALL OF LAKE SUPERIOR WED EVENING
THROUGH THU MORNING...WITH GALES GUSTS TO 35 KNOTS POSSIBLE OVER THE
EAST HALF. LIGHTER WINDS WILL RETURN WITH A HIGH PRESSURE RIDGE THU
NIGHT BEFORE SOUTHERLY WINDS OF UP TO 20 KNOTS ARRIVE AHEAD OF A LOW
PRESSURE TROUGH FRI. EXPECT THE TROUGH TO CROSS LAKE SUPERIOR ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON FOR MIZ012.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON FOR
LMZ221-248-250.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...KLUBER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
141 PM EDT TUE MAR 22 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM EDT TUE MAR 22 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW WNW FLOW ALOFT
OVER THE GREAT LKS BTWN GENERAL TROFFING OVER ERN CANADA/NE CONUS AND
AN UPR RDG OVER THE ROCKIES. THERE IS A GOOD DEAL OF MID/HI CLDS
STREAMING INTO THE AREA DOWNSTREAM OF A SHRTWV MOVING THRU THE NRN
PLAINS/ACCOMPANYING WAA...BUT VERY DRY LLVL AIR SHOWN ON THE 00Z INL
RAOB HAS SLOWED/LIMITED DEVELOPMENT OF BAND OF WAA PCPN STRETCHING
ACRS NCENTRAL MN TOWARD FAR WRN LK SUP DESPITE A FAIRLY TIGHT PRES
GRADIENT SHOWN BEST ON THE 285-290K ISENTROPIC SFCS /H85-7/ OVER THE
AREA AND ACCOMPANYING BAND OF SHARPER FGEN. THIS VERY DRY AIR IS
EVIDENT ALSO ON THE 00Z YPL/GRB/APX RAOBS AND HAS ALLOWED NOTHING
MORE THAN SOME FLURRIES INTO THE CWA AS OF 08Z DESITE THE THICKENING
CLDS/SHARPENING FGEN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/SN AMOUNTS
ASSOCIATED WITH WAA/FGEN FCST TO IMPACT THE CWA AHEAD OF SHRTWV NOW
MOVING THRU THE NRN PLAINS.
TODAY...SHRTWV MOVING THRU THE NRN PLAINS IS FCST TO SHEAR OUT AS IT
HEADS TO THE E IN FAST WNW FLOW ALOFT. ALTHOUGH THIS TREND AND
ABUNDANT DRY AIR ARE NOT FAVORABLE FOR PCPN...MODELS SHOW PRES
GRADIENT ON THE 285-290K ISENTROPIC SFC TIGHTENING OVER THE CWA AS
AXIS OF SHARPER FGEN IN THE H85-75 LYR CROSSES THE AREA THIS MRNG
BEFORE EXITING IN THE AFTN. SINCE THE PRES/THERMAL GRADIENT IS FCST
TO TIGHTEN...EXPECT SHORT TERM MODELS ARE ON THE RIGHT TRACK SHOWING
BAND OF SOME -SN DVLPG OVER MAINLY THE CNTRL CWA...WHICH WL BE UNDER
THE BAND OF SHARPER FGEN. FCST SPECIFIC HUMIDITY IN THE 2-3G/KG
RANGE WOULD SUPPORT UP TO ABOUT 3 INCHES OF SN DURING THE 6-9HR
PERIOD OF FORCING...BUT IMPACT OF LLVL DRY AIR AS WELL AS MARGINAL
ADDITIONAL DYANMIC SUPPORT RELATED TO THE SHEARING SHRTWV SUGGEST SN
TOTALS WL BE MAINLY UP TO 2 INCHES. IN FACT...THE WPC FCST SHOWS
ONLY 1 TO 2 INCHES OF SN UNDER THE FGEN BAND. THE ONE EXCEPTION MAY
BE OVER THE HIER TERRAIN OF THE NCENTRAL...WHERE UPSLOPING ENE WINDS
MAY AID LLVL MOISTENING/SN AMOUNTS. OVER THE FAR SCENTRAL... FCST
SDNGS SUG ANY PCPN WL BE AT LEAST MIXED WITH RA. BUT MANY OF THE
MODELS SHOW NO PCPN FALLING IN THIS AREA ANYWAY...SO WL PAINT THE
LOWER POPS IN THIS AREA. ONE OTHER IMPACT OF THE LLVL DRY AIR WL TO
SHARPEN THE NRN EDGE OF THE POPS SO THAT THE NRN KEWEENAW MAY SEE
LTL PCPN/SN AS WELL. AFTER THE SHARPER FGEN EXITS THIS AFTN...EXPECT
DIMINISHING POPS. PREVIOUS FCSTS HAVE SHOWN THE PCPN MAY TAPER TO
DRIZZLE...BUT CONCERNED THE DRYNESS OF THE LLVLS MAY LIMIT THIS
POTENTIAL. CONFINED THE MENTION OF DRIZZLE TO MAINLY THE HIER
TERRAIN OF THE NCENTRAL.
TNGT...WITH DEEP LYR QVECTOR DVGC/MID LVL DRYING DOMINATING...EXPECT
A GENERALLY DRY FCST. SOME OF THE MODELS SHOW SOME LGT PCPN
PERSISTING OVER THE HIER TERRAIN OF THE NCENTRAL WITH UPSLOPE NNE
FLOW ON THE SRN FLANK OF HI PRES BLDG INTO NW ONTARIO...BUT DRYNESS
OF THE AIRMASS TO THE N FAVORS THE DRIER PCPN FREE GUIDANCE FOR THIS
AREA. BUT WL HOLD ON TO SOME LO CHC POPS FOR SN OVER THE FAR
SCENTRAL...WHICH WL BE NEAR THE NRN EDGE OF THE PCPN SHIELD
ASSOCIATED WITH WAVES OF LO PRES MOVING ALONG STALLED SFC FNT OVER
THE LOWER GRT LKS. DEPENDING ON THE DEGREE OF CLRG ASSOCIATED WITH
THE INFLUX OF DRIER AIR FM THE N...TEMPS MAY FALL INTO THE TEENS AT
SOME OF THE COLDER SPOTS DURING THE NGT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 409 AM EDT TUE MAR 22 2016
ALL FOCUS REMAINS ON A STRONG EARLY SPRING STORM CROSSING THE GREAT
LAKES REGION LATE WEDNESDAY AFTERNOON INTO THURSDAY. THE 00Z
GUIDANCE PROVIDES SOME RESOLUTION IN THE ONGOING DIFFERENCES WITHIN
THE SUITE. THE GFS CONTINUES TO SHOW THE MORE PROGRESSIVE AND
NORTHWARD SOLUTION...BUT HAS TRENDED A TOUCH SOUTHWARD.
MEANWHILE...THE ECMWF REMAINS SLOWER AND FARTHER SOUTH...BUT MADE A
NORTHWARD SHIFT. THE CANADIAN GEM FALLS BETWEEN THESE SOLUTIONS.
ADDITIONALLY...THE GFS ENSEMBLE IS A BIT SLOWER AND FARTHER SOUTH
THAN THE OPERATIONAL GFS. THE CAUSE OF THE SIGNIFICANT DIFFERENCES
IS ACTUALLY QUITE SUBTLE...AND OCCURS OVER THE LEE OF THE ROCKIES
TONIGHT. FOR THE GFS...THE SLIGHTLY FARTHER NORTH PLACEMENT OF THE
MID-LEVEL TROUGH PASSING ACROSS THE WESTERN STATES ALLOWS FOR
PHASING WITH A BROAD NORTHERN STREAM TROUGH TO BEGIN EARLIER THAN
THE OTHER MODELS. MEANWHILE...THE ECMWF ATTEMPTS TO CUT OFF THE MID-
LEVEL TROUGH OVER WESTERN KANSAS. IN REALITY...THE DIFFERENCE
BETWEEN HEAVY SNOW (GFS) AND LITTLE SNOW (ECMWF) FOR MOST OF UPPER
MI IS HINGING ON THE ABILITY OF THE WEAK NORTHERN STREAM TROUGH TO
PICK UP THE APPROACHING WESTERN TROUGH...WITH LESS THAN TWO HUNDRED
MILES IN THE PLACEMENT OF THE MID-LEVEL LOW MAKING ALL THE
DIFFERENCE (NORTHERN CO FOR THE GFS VS CENTRAL/SOUTHERN CO FOR THE
ECMWF TONIGHT).
SIMPLY PUT...THERE IS VERY HIGH CONFIDENCE THAT HEAVY SNOW WILL FALL
SOMEWHERE BETWEEN LAKE SUPERIOR AND MILWAUKEE WEDNESDAY NIGHT INTO
THURSDAY...BUT PLACEMENT AND TIMING...BOTH TIED TO THE
AFOREMENTIONED DIFFERENCES...REMAIN IN QUESTION.
WITH ALL THAT SAID...CONFIDENCE IS GROWING THAT AT LEAST FAR
SOUTHERN PORTIONS OF UPPER MI WILL SEE WARNING-LEVEL CONDITIONS WITH
THE COMBINATION OF MODERATE TO HEAVY SNOW AND STRONG NE WINDS.
ADDITIONALLY...WITH A LOT OF DAILY TRAVEL TYPICALLY OCCURRING
BETWEEN MENOMINEE AND GREEN BAY...FELT IT WAS PRUDENT TO INCLUDE
MENOMINEE COUNTY FOR POTENTIALLY HIGHER IMPACTS. AS FOR THE NEXT
TIER OF COUNTIES TO THE NORTH...DICKINSON...DELTA...AND SOUTHERN
SCHOOLCRAFT...CONFIDENCE HAS INCREASED FOR AT LEAST MODERATE
SNOWFALL. HOWEVER...SUBSTANTIAL DRY AIR ADVECTING IN FROM HIGH
PRESSURE OVER NORTHERN ONTARIO ADDS A LIMITING FACTOR ON THE
NORTHWARD EXTENT OF THE SNOW. GIVEN THE BETTER AGREEMENT AMONG
MODELS...THE WATCH MAY NEED TO BE EXTENDED NORTHWARD...BUT WANTED TO
REMAIN MORE CONSERVATIVE AT THIS POINT GIVEN THE MODEL ISSUES.
THE WATCH FOR MENOMINEE COUNTY WAS ISSUED FROM 21Z WED TO 18Z
THU...WITH THE START TIME ENCOMPASSING THE ONSET OF SNOW FOR
THE EVENING COMMUTE.
BEYOND THU...SHORTWAVES WILL CONTINUE TO BRING PERIODS OF COLDER AIR
AND A COUPLE ROUNDS OF MIXED PRECIP TO THE AREA...ESPECIALLY SAT AND
SAT NIGHT. HOWEVER...CONFIDENCE IS LOW ON SPECIFICS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 141 PM EDT TUE MAR 22 2016
AS -SN DIMINISHES/ENDS THIS AFTN AND DRIER AIR GRADUALLY ARRIVES
FROM THE N AND E THRU TONIGHT...OCNL TO PREVAILING IFR CONDITIONS AT
KCMX/KSAW WILL IMPROVE TO MVFR THIS AFTN/EARLY EVENING THEN TO VFR
DURING THE EVENING...BEGINNING FIRST AT KCMX. AT KIWD...MVFR CIGS
WILL IMPROVE TO VFR LATER TONIGHT. WITH A COOL AIR MASS AND UPSLOPE
FLOW OFF LAKE SUPERIOR...MVFR CIGS MAY REDEVELOP FOR A TIME EARLY
WED MORNING AT ALL TERMINALS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EDT TUE MAR 22 2016
AN EXTENDED PERIOD OF NE WINDS ARE EXPECTED THROUGH THU AS RIDGING
SETTLES OVER NORTHERN ONTARIO AND A STRONG LOW PRESSURE SYSTEM
TRACKS FROM THE CENTRAL PLAINS ACROSS THE SOUTHERN GREAT LAKES.
WINDS TO 25 KNOTS ARE EXPECTED ACROSS WESTERN LAKE SUPERIOR TODAY.
WINDS BECOME 20 TO 30 KNOTS FOR ALL OF LAKE SUPERIOR WED EVENING
THROUGH THU MORNING...WITH GALES GUSTS TO 35 KNOTS POSSIBLE OVER THE
EAST HALF. LIGHTER WINDS WILL RETURN WITH A HIGH PRESSURE RIDGE THU
NIGHT BEFORE SOUTHERLY WINDS OF UP TO 20 KNOTS ARRIVE AHEAD OF A LOW
PRESSURE TROUGH FRI. EXPECT THE TROUGH TO CROSS LAKE SUPERIOR ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON FOR MIZ012.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON FOR
LMZ221-248-250.
&&
$$
SHORT TERM...KC
LONG TERM...KLUBER
AVIATION...ROLFSON
MARINE...KLUBER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
726 AM EDT TUE MAR 22 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM EDT TUE MAR 22 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW WNW FLOW ALOFT
OVER THE GREAT LKS BTWN GENERAL TROFFING OVER ERN CANADA/NE CONUS AND
AN UPR RDG OVER THE ROCKIES. THERE IS A GOOD DEAL OF MID/HI CLDS
STREAMING INTO THE AREA DOWNSTREAM OF A SHRTWV MOVING THRU THE NRN
PLAINS/ACCOMPANYING WAA...BUT VERY DRY LLVL AIR SHOWN ON THE 00Z INL
RAOB HAS SLOWED/LIMITED DEVELOPMENT OF BAND OF WAA PCPN STRETCHING
ACRS NCENTRAL MN TOWARD FAR WRN LK SUP DESPITE A FAIRLY TIGHT PRES
GRADIENT SHOWN BEST ON THE 285-290K ISENTROPIC SFCS /H85-7/ OVER THE
AREA AND ACCOMPANYING BAND OF SHARPER FGEN. THIS VERY DRY AIR IS
EVIDENT ALSO ON THE 00Z YPL/GRB/APX RAOBS AND HAS ALLOWED NOTHING
MORE THAN SOME FLURRIES INTO THE CWA AS OF 08Z DESITE THE THICKENING
CLDS/SHARPENING FGEN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/SN AMOUNTS
ASSOCIATED WITH WAA/FGEN FCST TO IMPACT THE CWA AHEAD OF SHRTWV NOW
MOVING THRU THE NRN PLAINS.
TODAY...SHRTWV MOVING THRU THE NRN PLAINS IS FCST TO SHEAR OUT AS IT
HEADS TO THE E IN FAST WNW FLOW ALOFT. ALTHOUGH THIS TREND AND
ABUNDANT DRY AIR ARE NOT FAVORABLE FOR PCPN...MODELS SHOW PRES
GRADIENT ON THE 285-290K ISENTROPIC SFC TIGHTENING OVER THE CWA AS
AXIS OF SHARPER FGEN IN THE H85-75 LYR CROSSES THE AREA THIS MRNG
BEFORE EXITING IN THE AFTN. SINCE THE PRES/THERMAL GRADIENT IS FCST
TO TIGHTEN...EXPECT SHORT TERM MODELS ARE ON THE RIGHT TRACK SHOWING
BAND OF SOME -SN DVLPG OVER MAINLY THE CNTRL CWA...WHICH WL BE UNDER
THE BAND OF SHARPER FGEN. FCST SPECIFIC HUMIDITY IN THE 2-3G/KG
RANGE WOULD SUPPORT UP TO ABOUT 3 INCHES OF SN DURING THE 6-9HR
PERIOD OF FORCING...BUT IMPACT OF LLVL DRY AIR AS WELL AS MARGINAL
ADDITIONAL DYANMIC SUPPORT RELATED TO THE SHEARING SHRTWV SUGGEST SN
TOTALS WL BE MAINLY UP TO 2 INCHES. IN FACT...THE WPC FCST SHOWS
ONLY 1 TO 2 INCHES OF SN UNDER THE FGEN BAND. THE ONE EXCEPTION MAY
BE OVER THE HIER TERRAIN OF THE NCENTRAL...WHERE UPSLOPING ENE WINDS
MAY AID LLVL MOISTENING/SN AMOUNTS. OVER THE FAR SCENTRAL... FCST
SDNGS SUG ANY PCPN WL BE AT LEAST MIXED WITH RA. BUT MANY OF THE
MODELS SHOW NO PCPN FALLING IN THIS AREA ANYWAY...SO WL PAINT THE
LOWER POPS IN THIS AREA. ONE OTHER IMPACT OF THE LLVL DRY AIR WL TO
SHARPEN THE NRN EDGE OF THE POPS SO THAT THE NRN KEWEENAW MAY SEE
LTL PCPN/SN AS WELL. AFTER THE SHARPER FGEN EXITS THIS AFTN...EXPECT
DIMINISHING POPS. PREVIOUS FCSTS HAVE SHOWN THE PCPN MAY TAPER TO
DRIZZLE...BUT CONCERNED THE DRYNESS OF THE LLVLS MAY LIMIT THIS
POTENTIAL. CONFINED THE MENTION OF DRIZZLE TO MAINLY THE HIER
TERRAIN OF THE NCENTRAL.
TNGT...WITH DEEP LYR QVECTOR DVGC/MID LVL DRYING DOMINATING...EXPECT
A GENERALLY DRY FCST. SOME OF THE MODELS SHOW SOME LGT PCPN
PERSISTING OVER THE HIER TERRAIN OF THE NCENTRAL WITH UPSLOPE NNE
FLOW ON THE SRN FLANK OF HI PRES BLDG INTO NW ONTARIO...BUT DRYNESS
OF THE AIRMASS TO THE N FAVORS THE DRIER PCPN FREE GUIDANCE FOR THIS
AREA. BUT WL HOLD ON TO SOME LO CHC POPS FOR SN OVER THE FAR
SCENTRAL...WHICH WL BE NEAR THE NRN EDGE OF THE PCPN SHIELD
ASSOCIATED WITH WAVES OF LO PRES MOVING ALONG STALLED SFC FNT OVER
THE LOWER GRT LKS. DEPENDING ON THE DEGREE OF CLRG ASSOCIATED WITH
THE INFLUX OF DRIER AIR FM THE N...TEMPS MAY FALL INTO THE TEENS AT
SOME OF THE COLDER SPOTS DURING THE NGT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 409 AM EDT TUE MAR 22 2016
ALL FOCUS REMAINS ON A STRONG EARLY SPRING STORM CROSSING THE GREAT
LAKES REGION LATE WEDNESDAY AFTERNOON INTO THURSDAY. THE 00Z
GUIDANCE PROVIDES SOME RESOLUTION IN THE ONGOING DIFFERENCES WITHIN
THE SUITE. THE GFS CONTINUES TO SHOW THE MORE PROGRESSIVE AND
NORTHWARD SOLUTION...BUT HAS TRENDED A TOUCH SOUTHWARD.
MEANWHILE...THE ECMWF REMAINS SLOWER AND FARTHER SOUTH...BUT MADE A
NORTHWARD SHIFT. THE CANADIAN GEM FALLS BETWEEN THESE SOLUTIONS.
ADDITIONALLY...THE GFS ENSEMBLE IS A BIT SLOWER AND FARTHER SOUTH
THAN THE OPERATIONAL GFS. THE CAUSE OF THE SIGNIFICANT DIFFERENCES
IS ACTUALLY QUITE SUBTLE...AND OCCURS OVER THE LEE OF THE ROCKIES
TONIGHT. FOR THE GFS...THE SLIGHTLY FARTHER NORTH PLACEMENT OF THE
MID-LEVEL TROUGH PASSING ACROSS THE WESTERN STATES ALLOWS FOR
PHASING WITH A BROAD NORTHERN STREAM TROUGH TO BEGIN EARLIER THAN
THE OTHER MODELS. MEANWHILE...THE ECMWF ATTEMPTS TO CUT OFF THE MID-
LEVEL TROUGH OVER WESTERN KANSAS. IN REALITY...THE DIFFERENCE
BETWEEN HEAVY SNOW (GFS) AND LITTLE SNOW (ECMWF) FOR MOST OF UPPER
MI IS HINGING ON THE ABILITY OF THE WEAK NORTHERN STREAM TROUGH TO
PICK UP THE APPROACHING WESTERN TROUGH...WITH LESS THAN TWO HUNDRED
MILES IN THE PLACEMENT OF THE MID-LEVEL LOW MAKING ALL THE
DIFFERENCE (NORTHERN CO FOR THE GFS VS CENTRAL/SOUTHERN CO FOR THE
ECMWF TONIGHT).
SIMPLY PUT...THERE IS VERY HIGH CONFIDENCE THAT HEAVY SNOW WILL FALL
SOMEWHERE BETWEEN LAKE SUPERIOR AND MILWAUKEE WEDNESDAY NIGHT INTO
THURSDAY...BUT PLACEMENT AND TIMING...BOTH TIED TO THE
AFOREMENTIONED DIFFERENCES...REMAIN IN QUESTION.
WITH ALL THAT SAID...CONFIDENCE IS GROWING THAT AT LEAST FAR
SOUTHERN PORTIONS OF UPPER MI WILL SEE WARNING-LEVEL CONDITIONS WITH
THE COMBINATION OF MODERATE TO HEAVY SNOW AND STRONG NE WINDS.
ADDITIONALLY...WITH A LOT OF DAILY TRAVEL TYPICALLY OCCURRING
BETWEEN MENOMINEE AND GREEN BAY...FELT IT WAS PRUDENT TO INCLUDE
MENOMINEE COUNTY FOR POTENTIALLY HIGHER IMPACTS. AS FOR THE NEXT
TIER OF COUNTIES TO THE NORTH...DICKINSON...DELTA...AND SOUTHERN
SCHOOLCRAFT...CONFIDENCE HAS INCREASED FOR AT LEAST MODERATE
SNOWFALL. HOWEVER...SUBSTANTIAL DRY AIR ADVECTING IN FROM HIGH
PRESSURE OVER NORTHERN ONTARIO ADDS A LIMITING FACTOR ON THE
NORTHWARD EXTENT OF THE SNOW. GIVEN THE BETTER AGREEMENT AMONG
MODELS...THE WATCH MAY NEED TO BE EXTENDED NORTHWARD...BUT WANTED TO
REMAIN MORE CONSERVATIVE AT THIS POINT GIVEN THE MODEL ISSUES.
THE WATCH FOR MENOMINEE COUNTY WAS ISSUED FROM 21Z WED TO 18Z
THU...WITH THE START TIME ENCOMPASSING THE ONSET OF SNOW FOR
THE EVENING COMMUTE.
BEYOND THU...SHORTWAVES WILL CONTINUE TO BRING PERIODS OF COLDER AIR
AND A COUPLE ROUNDS OF MIXED PRECIP TO THE AREA...ESPECIALLY SAT AND
SAT NIGHT. HOWEVER...CONFIDENCE IS LOW ON SPECIFICS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 723 AM EDT TUE MAR 22 2016
A BAND OF SN TO THE NE OF A STNRY FNT IN THE UPR MS RIVER VALLEY WL
IMPACT MAINLY SAW THIS MRNG...BRINGING MVFR/IFR CONDITIONS TO THAT
SITE. IMPACT OF DRY AIR PRESENT IN THE UPR LKS WL LIMIT CIG/VSBY
RESTRICTIONS AT IWD/CMX...BUT MVFR CONDITIONS WL OCCUR AT THOSE
PLACES AT LEAST OCNLY. ALTHOUGH THE PCPN WL DIMINISH THIS AFTN...
SOME LO CLDS/MVFR CIGS ARE LIKELY TO LINGER FOR A TIME UNTIL THE LLVL
NE FLOW TAPS ENUF DRY AIR TO BRING A RETURN OF VFR CIGS. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EDT TUE MAR 22 2016
AN EXTENDED PERIOD OF NE WINDS ARE EXPECTED THROUGH THU AS RIDGING
SETTLES OVER NORTHERN ONTARIO AND A STRONG LOW PRESSURE SYSTEM
TRACKS FROM THE CENTRAL PLAINS ACROSS THE SOUTHERN GREAT LAKES.
WINDS TO 25 KNOTS ARE EXPECTED ACROSS WESTERN LAKE SUPERIOR TODAY.
WINDS BECOME 20 TO 30 KNOTS FOR ALL OF LAKE SUPERIOR WED EVENING
THROUGH THU MORNING...WITH GALES GUSTS TO 35 KNOTS POSSIBLE OVER THE
EAST HALF. LIGHTER WINDS WILL RETURN WITH A HIGH PRESSURE RIDGE THU
NIGHT BEFORE SOUTHERLY WINDS OF UP TO 20 KNOTS ARRIVE AHEAD OF A LOW
PRESSURE TROUGH FRI. EXPECT THE TROUGH TO CROSS LAKE SUPERIOR ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON FOR MIZ012.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON FOR
LMZ221-248-250.
&&
$$
SHORT TERM...KC
LONG TERM...KLUBER
AVIATION...KC
MARINE...KLUBER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
413 AM EDT TUE MAR 22 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM EDT TUE MAR 22 2016
00Z RAOBS/LATEST WV IMAGERY AND RAP ANALYSIS SHOW WNW FLOW ALOFT
OVER THE GREAT LKS BTWN GENERAL TROFFING OVER ERN CANADA/NE CONUS AND
AN UPR RDG OVER THE ROCKIES. THERE IS A GOOD DEAL OF MID/HI CLDS
STREAMING INTO THE AREA DOWNSTREAM OF A SHRTWV MOVING THRU THE NRN
PLAINS/ACCOMPANYING WAA...BUT VERY DRY LLVL AIR SHOWN ON THE 00Z INL
RAOB HAS SLOWED/LIMITED DEVELOPMENT OF BAND OF WAA PCPN STRETCHING
ACRS NCENTRAL MN TOWARD FAR WRN LK SUP DESPITE A FAIRLY TIGHT PRES
GRADIENT SHOWN BEST ON THE 285-290K ISENTROPIC SFCS /H85-7/ OVER THE
AREA AND ACCOMPANYING BAND OF SHARPER FGEN. THIS VERY DRY AIR IS
EVIDENT ALSO ON THE 00Z YPL/GRB/APX RAOBS AND HAS ALLOWED NOTHING
MORE THAN SOME FLURRIES INTO THE CWA AS OF 08Z DESITE THE THICKENING
CLDS/SHARPENING FGEN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/SN AMOUNTS
ASSOCIATED WITH WAA/FGEN FCST TO IMPACT THE CWA AHEAD OF SHRTWV NOW
MOVING THRU THE NRN PLAINS.
TODAY...SHRTWV MOVING THRU THE NRN PLAINS IS FCST TO SHEAR OUT AS IT
HEADS TO THE E IN FAST WNW FLOW ALOFT. ALTHOUGH THIS TREND AND
ABUNDANT DRY AIR ARE NOT FAVORABLE FOR PCPN...MODELS SHOW PRES
GRADIENT ON THE 285-290K ISENTROPIC SFC TIGHTENING OVER THE CWA AS
AXIS OF SHARPER FGEN IN THE H85-75 LYR CROSSES THE AREA THIS MRNG
BEFORE EXITING IN THE AFTN. SINCE THE PRES/THERMAL GRADIENT IS FCST
TO TIGHTEN...EXPECT SHORT TERM MODELS ARE ON THE RIGHT TRACK SHOWING
BAND OF SOME -SN DVLPG OVER MAINLY THE CNTRL CWA...WHICH WL BE UNDER
THE BAND OF SHARPER FGEN. FCST SPECIFIC HUMIDITY IN THE 2-3G/KG
RANGE WOULD SUPPORT UP TO ABOUT 3 INCHES OF SN DURING THE 6-9HR
PERIOD OF FORCING...BUT IMPACT OF LLVL DRY AIR AS WELL AS MARGINAL
ADDITIONAL DYANMIC SUPPORT RELATED TO THE SHEARING SHRTWV SUGGEST SN
TOTALS WL BE MAINLY UP TO 2 INCHES. IN FACT...THE WPC FCST SHOWS
ONLY 1 TO 2 INCHES OF SN UNDER THE FGEN BAND. THE ONE EXCEPTION MAY
BE OVER THE HIER TERRAIN OF THE NCENTRAL...WHERE UPSLOPING ENE WINDS
MAY AID LLVL MOISTENING/SN AMOUNTS. OVER THE FAR SCENTRAL... FCST
SDNGS SUG ANY PCPN WL BE AT LEAST MIXED WITH RA. BUT MANY OF THE
MODELS SHOW NO PCPN FALLING IN THIS AREA ANYWAY...SO WL PAINT THE
LOWER POPS IN THIS AREA. ONE OTHER IMPACT OF THE LLVL DRY AIR WL TO
SHARPEN THE NRN EDGE OF THE POPS SO THAT THE NRN KEWEENAW MAY SEE
LTL PCPN/SN AS WELL. AFTER THE SHARPER FGEN EXITS THIS AFTN...EXPECT
DIMINISHING POPS. PREVIOUS FCSTS HAVE SHOWN THE PCPN MAY TAPER TO
DRIZZLE...BUT CONCERNED THE DRYNESS OF THE LLVLS MAY LIMIT THIS
POTENTIAL. CONFINED THE MENTION OF DRIZZLE TO MAINLY THE HIER
TERRAIN OF THE NCENTRAL.
TNGT...WITH DEEP LYR QVECTOR DVGC/MID LVL DRYING DOMINATING...EXPECT
A GENERALLY DRY FCST. SOME OF THE MODELS SHOW SOME LGT PCPN
PERSISTING OVER THE HIER TERRAIN OF THE NCENTRAL WITH UPSLOPE NNE
FLOW ON THE SRN FLANK OF HI PRES BLDG INTO NW ONTARIO...BUT DRYNESS
OF THE AIRMASS TO THE N FAVORS THE DRIER PCPN FREE GUIDANCE FOR THIS
AREA. BUT WL HOLD ON TO SOME LO CHC POPS FOR SN OVER THE FAR
SCENTRAL...WHICH WL BE NEAR THE NRN EDGE OF THE PCPN SHIELD
ASSOCIATED WITH WAVES OF LO PRES MOVING ALONG STALLED SFC FNT OVER
THE LOWER GRT LKS. DEPENDING ON THE DEGREE OF CLRG ASSOCIATED WITH
THE INFLUX OF DRIER AIR FM THE N...TEMPS MAY FALL INTO THE TEENS AT
SOME OF THE COLDER SPOTS DURING THE NGT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 409 AM EDT TUE MAR 22 2016
ALL FOCUS REMAINS ON A STRONG EARLY SPRING STORM CROSSING THE GREAT
LAKES REGION LATE WEDNESDAY AFTERNOON INTO THURSDAY. THE 00Z
GUIDANCE PROVIDES SOME RESOLUTION IN THE ONGOING DIFFERENCES WITHIN
THE SUITE. THE GFS CONTINUES TO SHOW THE MORE PROGRESSIVE AND
NORTHWARD SOLUTION...BUT HAS TRENDED A TOUCH SOUTHWARD.
MEANWHILE...THE ECMWF REMAINS SLOWER AND FARTHER SOUTH...BUT MADE A
NORTHWARD SHIFT. THE CANADIAN GEM FALLS BETWEEN THESE SOLUTIONS.
ADDITIONALLY...THE GFS ENSEMBLE IS A BIT SLOWER AND FARTHER SOUTH
THAN THE OPERATIONAL GFS. THE CAUSE OF THE SIGNIFICANT DIFFERENCES
IS ACTUALLY QUITE SUBTLE...AND OCCURS OVER THE LEE OF THE ROCKIES
TONIGHT. FOR THE GFS...THE SLIGHTLY FARTHER NORTH PLACEMENT OF THE
MID-LEVEL TROUGH PASSING ACROSS THE WESTERN STATES ALLOWS FOR
PHASING WITH A BROAD NORTHERN STREAM TROUGH TO BEGIN EARLIER THAN
THE OTHER MODELS. MEANWHILE...THE ECMWF ATTEMPTS TO CUT OFF THE MID-
LEVEL TROUGH OVER WESTERN KANSAS. IN REALITY...THE DIFFERENCE
BETWEEN HEAVY SNOW (GFS) AND LITTLE SNOW (ECMWF) FOR MOST OF UPPER
MI IS HINGING ON THE ABILITY OF THE WEAK NORTHERN STREAM TROUGH TO
PICK UP THE APPROACHING WESTERN TROUGH...WITH LESS THAN TWO HUNDRED
MILES IN THE PLACEMENT OF THE MID-LEVEL LOW MAKING ALL THE
DIFFERENCE (NORTHERN CO FOR THE GFS VS CENTRAL/SOUTHERN CO FOR THE
ECMWF TONIGHT).
SIMPLY PUT...THERE IS VERY HIGH CONFIDENCE THAT HEAVY SNOW WILL FALL
SOMEWHERE BETWEEN LAKE SUPERIOR AND MILWAUKEE WEDNESDAY NIGHT INTO
THURSDAY...BUT PLACEMENT AND TIMING...BOTH TIED TO THE
AFOREMENTIONED DIFFERENCES...REMAIN IN QUESTION.
WITH ALL THAT SAID...CONFIDENCE IS GROWING THAT AT LEAST FAR
SOUTHERN PORTIONS OF UPPER MI WILL SEE WARNING-LEVEL CONDITIONS WITH
THE COMBINATION OF MODERATE TO HEAVY SNOW AND STRONG NE WINDS.
ADDITIONALLY...WITH A LOT OF DAILY TRAVEL TYPICALLY OCCURRING
BETWEEN MENOMINEE AND GREEN BAY...FELT IT WAS PRUDENT TO INCLUDE
MENOMINEE COUNTY FOR POTENTIALLY HIGHER IMPACTS. AS FOR THE NEXT
TIER OF COUNTIES TO THE NORTH...DICKINSON...DELTA...AND SOUTHERN
SCHOOLCRAFT...CONFIDENCE HAS INCREASED FOR AT LEAST MODERATE
SNOWFALL. HOWEVER...SUBSTANTIAL DRY AIR ADVECTING IN FROM HIGH
PRESSURE OVER NORTHERN ONTARIO ADDS A LIMITING FACTOR ON THE
NORTHWARD EXTENT OF THE SNOW. GIVEN THE BETTER AGREEMENT AMONG
MODELS...THE WATCH MAY NEED TO BE EXTENDED NORTHWARD...BUT WANTED TO
REMAIN MORE CONSERVATIVE AT THIS POINT GIVEN THE MODEL ISSUES.
THE WATCH FOR MENOMINEE COUNTY WAS ISSUED FROM 21Z WED TO 18Z
THU...WITH THE START TIME ENCOMPASSING THE ONSET OF SNOW FOR
THE EVENING COMMUTE.
BEYOND THU...SHORTWAVES WILL CONTINUE TO BRING PERIODS OF COLDER AIR
AND A COUPLE ROUNDS OF MIXED PRECIP TO THE AREA...ESPECIALLY SAT AND
SAT NIGHT. HOWEVER...CONFIDENCE IS LOW ON SPECIFICS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 121 AM EDT TUE MAR 22 2016
A BAND OF SN FORMING N OF A STNRY FNT OVER THE NRN PLAINS AND UPR
MIDWEST WL OVERSPREAD UPR MI LATER TNGT...WITH LOWERING CIGS TO MVFR
AND VSBYS INTO THE IFR RANGE CONTINUING INTO TUE MORNING. IFR
VSBYS/CIGS IN MIX OF -SN/DZ AND MAYBE EVEN FZDZ COULD CONTINUE AT
KSAW IN UPSLOPE NE FLOW INTO MID MON AFTERNOON. EXPECT PCPN TO END W
TO E TUE AFTERNOON/EARLY EVENING WITH IMPROVEMENT TO MVFR AT KSAW
AND KIWD AND TO VFR AT KCMX AS BUILDING CANADIAN HIGH PRESSURE
BRINGS DRIER AIR INTO THE AREA IN A NE FLOW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 AM EDT TUE MAR 22 2016
AN EXTENDED PERIOD OF NE WINDS ARE EXPECTED THROUGH THU AS RIDGING
SETTLES OVER NORTHERN ONTARIO AND A STRONG LOW PRESSURE SYSTEM
TRACKS FROM THE CENTRAL PLAINS ACROSS THE SOUTHERN GREAT LAKES.
WINDS TO 25 KNOTS ARE EXPECTED ACROSS WESTERN LAKE SUPERIOR TODAY.
WINDS BECOME 20 TO 30 KNOTS FOR ALL OF LAKE SUPERIOR WED EVENING
THROUGH THU MORNING...WITH GALES GUSTS TO 35 KNOTS POSSIBLE OVER THE
EAST HALF. LIGHTER WINDS WILL RETURN WITH A HIGH PRESSURE RIDGE THU
NIGHT BEFORE SOUTHERLY WINDS OF UP TO 20 KNOTS ARRIVE AHEAD OF A LOW
PRESSURE TROUGH FRI. EXPECT THE TROUGH TO CROSS LAKE SUPERIOR ON SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
AFTERNOON FOR MIZ012.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WATCH FROM WEDNESDAY EVENING THROUGH THURSDAY AFTERNOON FOR
LMZ221-248-250.
&&
$$
SHORT TERM...KC
LONG TERM...KLUBER
AVIATION...VOSS
MARINE...KLUBER
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
401 PM CDT TUE MAR 22 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 400 PM CDT TUE MAR 22 2016
WATER VAPOR THIS AFTERNOON SHOWS OUR STORM FOR WEDNESDAY WORKING
ACROSS UTAH. AS IT CONTINUES TO PUSH THROUGH COLORADO
TONIGHT...CYCLOGENESIS WILL ENSUE ALONG THE COLORADO/KANSAS BORDER.
MAIN CHANGE IN THE FORECAST FOR TONIGHT WAS A REDUCTION OF POPS WITH
THE EXPECTED LEAD FGEN BAND ALONG WHAT AMOUNTS TO A WARM FRONT
AROUND H7. FORECAST SOUNDINGS FROM THE NAM/RAP HIGHLIGHT THE PROBLEM
FOR TONIGHT AND IT IS VERY DRY AIR THAT IS JUST SLOW TO BUDGE BELOW
10K FT. THE MODEL THAT IS MOST AGGRESSIVE WITH MOISTENING THIS
LATER IS THE GFS. HOWEVER...THE RAP HAS OUR AREA DRY THROUGH 12Z
WEDNESDAY...WITH THE HOPWRF MEMBERS NOT SHOWING ANYTHING COMING INTO
THE WEST UNTIL AROUND 9Z...SO WAS RELUCTANT TO GO AS AGGRESSIVE AS
WHAT THE GFS HAS. FOR POPS THOUGH...DID FOLLOW A TREND OF THE
CAMS...WHICH SHOWS A BAND OF PRECIP MOVING INTO WEST CENTRAL MN
BETWEEN 6Z AND 9Z WITH THAT BAND TRYING TO FILL IN OVER TOWARD RED
WING THROUGH 12Z. FOR P-TYPE...WITH TEMPERATURES NOW IN THE 50S
SOUTH OF I-94...WILL TAKE SOME TIME FOR US TO COOL DOWN ENOUGH TO
ALLOW SNOW...WITH INITIAL PRECIP STARTING OUT AS A MIX THAT WILL
PROGRESSIVELY CHANGE TO MOSTLY SNOW BY 12Z WEDNESDAY.
THE FORECAST FOR WEDNESDAY AND WEDNESDAY NIGHT REMAINS A
CHALLENGE AS MODEL SOLUTIONS TODAY HAVE ADDED MORE SPREAD TO THE
SNOWFALL FORECAST. IN A NUTSHELL...THE NAM AND GFS HAVE PUSHED
THE HEAVIER PRECIPITATION AMOUNTS FARTHER NORTH...WHICH WOULD
GIVE AT LEAST THE SOUTHERN HALF OF THE TWIN CITIES HEAVY
SNOWFALL...WHILE THE ECMWF HAS PUSHED THINGS QUITE A BIT TO THE
SOUTH. IN FACT...IF THE ECMWF VERIFIES...MOST OF THE TWIN CITIES
WILL NOT EVEN SEE SNOW WITH ONLY SOUTHEAST MINNESOTA HAVING HEAVY
SNOW. TRYING TO SORT OUT THE DIFFERENCES STARTS WITH WHERE THE
PRECIPITATION BEGINS EARLY WEDNESDAY MORNING. THE CAMS AS WELL AS
THE NAM AND GFS WOULD HAVE A BAND OF RAIN ACROSS SOUTHERN AREAS OF
MINNESOTA EARLY WEDNESDAY MORNING ALONG A MID LEVEL WARM FRONT AND
INCREASING FRONTOGENESIS. THE ECMWF WOULD HAVE THE PRECIPITATION
DEVELOPING IN IA AND SPREADING EAST NORTHEAST INTO WI. THE
DIFFERENCE SEEMS TIED TO UPPER LEVEL CONFLUENCE BETWEEN THE
SOLUTIONS WITH THE ECMWF HAVING THE CONFLUENT ZONE ACROSS SOUTHERN
MN.
THEREFORE...WITH KEPT THE WINTER STORM WATCH GOING FROM THE TWIN
CITIES ON SOUTHWEST THROUGH REDWOOD FALLS AND NEW ULM FOR
WEDNESDAY AND WEDNESDAY NIGHT. THE NORTHERN SOLUTIONS WOULD GIVE
THESE AREAS TWO CHANCES FOR ACCUMULATION SNOW. THE FIRST WOULD BE
IN THE LATE MORNING AND EARLY AFTERNOON WITH THE MID LEVEL
FRONTOGENESIS AND THEN AGAIN IN THE EVENING WITH THE DEFORMATION
ZONE. TOTALS COULD REACH INTO THE 6 TO 8 INCH RANGE. OFFICIAL
AMOUNTS IN THE GRIDS ARE MORE IN THE 2 TO 5 INCH RANGE. WITH
CONFIDENCE HIGHER ACROSS SOUTHERN MN AND ADJOINING AREAS OF WEST
CENTRAL WI FOR HEAVY SNOW...THE WATCH WAS CHANGED TO A WARNING.
SNOW TOTALS FROM 6 TO 12 INCHES ARE LIKELY WITH THE HIGH END
AMOUNTS FROM ALBERT LEA TO NEAR EAU CLAIRE. IN ADDITION...THESE
AREAS WILL ALSO EXPERIENCE STRONG NORTHEAST WINDS FROM 25 TO 30
MPH CAUSING SOME BLOWING AND DRIFTING SNOW. SOME TREE DAMAGE MAY
OCCUR DUE TO THE HEAVY SNOW AND STRONG WINDS WHICH COULD CAUSE
SOME POWER OUTAGES. TRAVEL WILL LIKELY BE QUITE DIFFICULT IN
THESE AREAS. SNOWFALL RATES OF 2 TO 3 INCHES PER HOUR ARE POSSIBLE
WITH A NICE BULLSEYE SEEN WITH THE OMEGA NEARLY MAXED OUT IN THE
DENDRITIC GROWTH ZONE.
THE SNOW WILL END FOR THE FAR EASTERN AREAS OF THE FA EARLY THURSDAY
MORNING WITH DECREASING CLOUDINESS ACROSS THE AREA DURING THE DAY.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 400 PM CDT TUE MAR 22 2016
A BROAD UPPER LEVEL WAVE WILL MOVE ACROSS THE REGION WILL LEAD TO A
WEAK SURFACE TROUGH AND SOME LIGHT PRECIPITATION OVER THE WEEKEND.
TEMPERATURES WILL BE START ABOUT 5 DEGREES BELOW NORMAL...BUT WILL
GRADUALLY MODERATE TO NEAR 50 DEGREES BY MONDAY AND TUESDAY WHICH IS
NEAR OR SLIGHTLY ABOVE THE SEASONAL AVERAGE FOR LATE MARCH.
THE MAIN CHALLENGE WILL BE TEMPERATURES SINCE THERE SHOULD STILL BE
A FAIRLY SUBSTANTIAL SNOWPACK ACROSS THE SOUTHEAST PART OF THE
FORECAST AREA. AS MENTIONED ABOVE...A WEAK UPPER LEVEL PV ANOMALY
WILL MOVE ACROSS THE REGION AND LEAD TO CLOUDS AND LIGHT
PRECIPITATION FRIDAY NIGHT INTO SATURDAY. PRECIP WILL BE A WINTRY
MIX...WITH SNOW FAVORED OVERNIGHT...AND RAIN DURING THE DAY AS THE
THERMAL PROFILE WARMS. NO SIGNIFICANT ACCUMULATION IS EXPECTED.
TEMPERATURES WILL GRADUALLY WARM INTO EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 155 PM CDT TUE MAR 22 2016
TODAY ITS NORTHEAST WINDS AND VFR CONDITIONS. HAVE STARTED
DELAYING BOTH THE ARRIVAL OF MVFR CIGS AND SNOW...WITH DRY LOW
LEVEL AIR CURRENTLY IN PLACE LOOKING TO IMPACT PRECIP ONSET.
FOR THE LEAD FGEN BAND...GUIDANCE HAS DELAYED ITS START TIME TO
MAINLY AFTER 9Z AND START IT OUT FROM ABOUT REDWOOD FALLS TO RED
WING...THEN LIFT IT NORTH TOWARD MSP/EAU DURING THE LATE
MORNING/AFTERNOON. STILL A GOOD DEAL OF SPREAD IN THE MODELS WITH
WHEN THE DRY AIR WILL BE OVERCOME AND WHEN PRECIP WILL START...BUT
STARTED TO TREND US TOWARD A BLEND BETWEEN THE EARLY GFS AND THE
LATE NAM. NOT OVERLY CONFIDENT ON MVFR CIG FORECAST TONIGHT
EITHER...WITH EVERY HOUR THE GFS LAMP SEEMINGLY DELAYS THE ARRIVAL
OF MVFR CIGS FURTHER AND FURTHER AND THE HRRR CIGS ARE NOT OVERLY
AGGRESSIVE WITH DROPPING THE STRATUS OVER NRN WI SW THROUGH THE
NIGHT. CONDITIONS WITH THE SNOWSTORM WEDNESDAY LOOK TO DETERIORATE
QUICKLY AROUND 18Z WED.
KMSP...LARGE SPREAD IN MODELS WITH START TIME FOR SNOW WITH
ANYWHERE FROM 12Z ON THE GFS TO 22Z ON THE NAM...SO WENT DOWN THE
MIDDLE FOR NOW. FOR THE MVFR CIGS...RAP/NAM WOULD SAY THE EARLIEST
WE WOULD SEE MVFR CIGS IS 6Z...THOUGH I COULD SEE FURTHER DELAYS
HAPPENING.
/OUTLOOK FOR KMSP/
THU...SN ENDING IN MRNG. AFTN VFR. WINDS N 10-20KTS.
FRI...VFR. WINDS S 10-20 KTS.
SAT...MVFR. CHC -RA/-SN. WINDS NW 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING FROM 3 PM WEDNESDAY TO 9 AM CDT THURSDAY
FOR WIZ024>028.
WINTER STORM WATCH FROM WEDNESDAY AFTERNOON THROUGH THURSDAY
MORNING FOR WIZ023.
MN...WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
MORNING FOR MNZ060-062-063-065>070-073>076.
WINTER STORM WARNING FROM 10 AM WEDNESDAY TO 9 AM CDT THURSDAY
FOR MNZ077-078-082>085-091>093.
&&
$$
SHORT TERM...MPG/RAH
LONG TERM...JRB
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
155 PM CDT TUE MAR 22 2016
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 400 AM CDT TUE MAR 22 2016
AT 3 AM THIS MORNING THE FRONT THAT WILL EVENTUALLY DETERMINE WHERE
THE MIDWEEK WINTER STORM WILL TRACK HAS SAGGED SOUTH TO NEAR REDWOOD
FALLS...SOUTHERN TWIN CITIES...AND EAU CLAIRE. OTHER THAN A WIND
SHIFT...LITTLE SENSIBLE WEATHER WILL ACCOMPANY THIS FRONT TODAY. IN
FACT...WITH VERY LITTLE LOW LEVEL CAA BEHIND IT AND TEMPERATURES
ALOFT QUITE A BIT WARMER THAN YESTERDAY...HIGH TEMPERATURES WILL
ALSO BE SEVERAL DEGREES WARMER IN SPOTS...PARTICULARLY ACROSS
WESTERN WI. SOME BREAKS IN THE OVERCAST CAN BE EXPECTED...BUT IT
WILL BE A RATHER CLOUDY DAY OVERALL.
MAIN CONCERN FOR TONIGHT IS WHETHER A NARROW FRONTOGENETICALLY-
DRIVEN BAND OF RAIN/SNOW DEVELOPS AND WHERE. SEVERAL HI-RES MODELS
SUGGEST DEVELOPMENT FROM WEST CENTRAL MN EARLY THIS EVENING TO EAST
CENTRAL MN AND WEST CENTRAL WI LATE THIS EVENING AND OVERNIGHT.
TEMPERATURES ALOFT WILL BE LARGELY UNSUPPORTIVE OF SNOW UNTIL THE
COLUMN COOLS AS CAA BEGINS TO STRENGTHEN AFTER MIDNIGHT.
NEVERTHELESS...MARGINAL BOUNDARY LAYER TEMPERATURES WILL LIMIT MUCH
SNOW ACCUMULATION TO AFTER 09Z...AND BY THEN THE BAND MAY ALREADY BE
WEAKENING. PERHAPS A DUSTING TO A HALF INCH IN SPOTS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 400 AM CDT TUE MAR 22 2016
CONFIDENCE CONTINUES TO INCREASE THAT A MORE NORTHWARD SHIFT IN
THE TRACK OF THE STORM WILL YIELD HIGHER SNOW TOTALS NORTH...INTO
THE TWIN CITIES AREA AND MUCH OF WEST CENTRAL WISCONSIN. THE
ACTUAL LOCATION OF THE HEAVIER SNOW BAND REMAINS UNCLEAR AND
FURTHER MOVEMENT OF THE STORM COULD OCCUR IN LATER FORECASTS.
WE DID ADD A FEW COUNTIES TO THE NORTH BECAUSE OF THE MAJORITY OF
DETERMINISTIC MODELS(SAVE THE ECMWF) HAVE REALLY CONVERGED ON
THIS NORTHWARD SHIFT.
SAID MODELS ARE A BIT SLOWER AND MAINTAIN A CLOSED CIRCULATION
WITH THE UPPER TROUGH AS IT SWINGS ACROSS EASTERN IOWA AND
WISCONSIN. IT RETAINS A 700MB CIRCULATION WITH A DEFINITE
DEFORMATION BAND DEVELOPING INTO SOUTHWEST MN AND WEST CENTRAL
WISCONSIN THIS WEDNESDAY AFTERNOON AND NIGHT. IN THE INTERIM...
CENTRAL MN IS UNDER THE GUN AS A NICE FRONTOGENETICALLY FORCED
BAND DEVELOPS FROM SOUTHWEST MN INTO THE METRO AREA IN THE
MORNING. THIS FORCING IS RATHER HIGH/600MB OR ABOVE...BUT THE
ATMOSPHERE DOES SATURATE AS THE TROUGH/FORCING APPROACHES AND THE
ENTRANCE REGION OF THE NORTHERN STREAM JET REMAINS LOCKED OVER
NORTHERN MN. THE DENDRITIC GROWTH ZONE IS ALSO DIRECTED NORTH
WITH STRONG VERTICAL MOTION IN THE GROWTH ZONE. THE SREF HAS BEEN
LIFTING THE DGZ FARTHER NORTH WITH EACH OF ITS MODEL RUNS AND NOW
ALSO HAS FAIRLY HIGH PROBABILITIES FOR AT LEAST 1 INCH AN HOUR
SNOWFALL RATES IN THIS AREA. WE SHOULD SEE SNOW DEVELOP WEDNESDAY
MORNING ACROSS THE CENTRAL CWA AND THEN REDIRECT ITSELF TO THE
SOUTHEAST...AND INTO WISCONSIN AS THE UPPER LOW BEGINS TO LIFT
OUT.
SNOWFALL FORECAST AMOUNTS STILL APPEAR TO BE IN THE 6 TO 12 INCH
RANGE IN THE WATCH AREA. THE HIGHER END AMOUNTS SHOULD DEVELOP
INTO SOUTHEAST MN AND A PORTION OF WEST CENTRAL WISCONSIN...
MAINLY ALONG THE I35 CORRIDOR IN SOUTHERN MN AND ALONG I94 IN WEST
CENTRAL WISCONSIN. WINDS ARE EXPECTED TO INCREASE WEDNESDAY AS THE
SURFACE LOW TRACKS SLOWLY NORTHEAST AND DEEPENS. WE COULD SEE
BLOWING/DRIFTING SNOW DEVELOP...ESPECIALLY INTO SOUTH CENTRAL
MINNESOTA WEDNESDAY AFTERNOON AND EVENING. ALSO...WE MENTIONED A
SLIGHT CHANCE FOR THUNDER ALONG I90 AS WELL WEDNESDAY AFTERNOON.
THE STORM EXITS THE EAST PORTION OF THE FA BY MIDDAY THURSDAY
WITH INCREASING SUNSHINE EXPECTED. IT WILL REMAIN
COOL...ESPECIALLY IF WE SEE THE FORECAST SNOW OVER THE SOUTH AND
EAST CWA.
THE LONGER TERM STILL HAS A CLIPPER SYSTEM DROPPING SOUTHEAST
OVER THE REGION FRIDAY INTO SATURDAY. A MIXED RAIN/SNOW EVENT IS
ANTICIPATED AT THIS TIME. TEMPERATURES WILL MODERATE INTO THE
WEEKEND BUT WILL RANGE CLOSE TO NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 155 PM CDT TUE MAR 22 2016
TODAY ITS NORTHEAST WINDS AND VFR CONDITIONS. HAVE STARTED
DELAYING BOTH THE ARRIVAL OF MVFR CIGS AND SNOW...WITH DRY LOW
LEVEL AIR CURRENTLY IN PLACE LOOKING TO IMPACT PRECIP ONSET.
FOR THE LEAD FGEN BAND...GUIDANCE HAS DELAYED ITS START TIME TO
MAINLY AFTER 9Z AND START IT OUT FROM ABOUT REDWOOD FALLS TO RED
WING...THEN LIFT IT NORTH TOWARD MSP/EAU DURING THE LATE
MORNING/AFTERNOON. STILL A GOOD DEAL OF SPREAD IN THE MODELS WITH
WHEN THE DRY AIR WILL BE OVERCOME AND WHEN PRECIP WILL START...BUT
STARTED TO TREND US TOWARD A BLEND BETWEEN THE EARLY GFS AND THE
LATE NAM. NOT OVERLY CONFIDENT ON MVFR CIG FORECAST TONIGHT
EITHER...WITH EVERY HOUR THE GFS LAMP SEEMINGLY DELAYS THE ARRIVAL
OF MVFR CIGS FURTHER AND FURTHER AND THE HRRR CIGS ARE NOT OVERLY
AGGRESSIVE WITH DROPPING THE STRATUS OVER NRN WI SW THROUGH THE
NIGHT. CONDITIONS WITH THE SNOWSTORM WEDNESDAY LOOK TO DETERIORATE
QUICKLY AROUND 18Z WED.
KMSP...LARGE SPREAD IN MODELS WITH START TIME FOR SNOW WITH
ANYWHERE FROM 12Z ON THE GFS TO 22Z ON THE NAM...SO WENT DOWN THE
MIDDLE FOR NOW. FOR THE MVFR CIGS...RAP/NAM WOULD SAY THE EARLIEST
WE WOULD SEE MVFR CIGS IS 6Z...THOUGH I COULD SEE FURTHER DELAYS
HAPPENING.
/OUTLOOK FOR KMSP/
THU...SN ENDING IN MRNG. AFTN VFR. WINDS N 10-20KTS.
FRI...VFR. WINDS S 10-20 KTS.
SAT...MVFR. CHC -RA/-SN. WINDS NW 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
MORNING FOR WIZ015-016-023>028.
MN...WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
MORNING FOR MNZ060-062-063-067>070-073>078-082>085-091>093.
&&
$$
SHORT TERM...BORGHOFF
LONG TERM...DWE
AVIATION...MPG
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
843 PM MDT WED MAR 23 2016
.UPDATE...
SHORTWAVE CROSSING THE AREA THIS EVENING WAS DIFFICULT TO SEE IN
WATER VAPOR IMAGERY...BUT WAS GENERATING A FEW SHOWERS OVER N
CENTRAL/NE MT AND NE AND SW OF KBIL. MESOANALYSIS SHOWED DECENT
INSTABILITY WITH THE WAVE WITH 100 J/KG OF CAPE AND STEEP LAPSE
RATES. THE HRRR ANALYSIS OF QPF LOOKED REASONABLE AND KEPT SOME
QPF E OF KBIL AFTER 06Z. SO ADJUSTED POPS BASED ON RADAR TRENDS
BEFORE 06Z...AND ADJUSTED POPS AFTER 06Z BASED ON HRRR.
OTHERWISE...SLIGHTLY ADJUSTED WINDS AND SKY COVER BASED ON LATEST
OBSERVED AND MODEL TRENDS. WILL NOT MENTION FOG AS
TEMPERATURE/DEWPOINT SPREADS GENERALLY WILL NOT SUPPORT IT AND THE
FEW SHOWERS IN THE E AFTER 06Z SHOULD KEEP THE AIRMASS MIXED
ENOUGH TO PRECLUDE FOG.
STRONG SHORTWAVE AND JET DYNAMICS...ALONG WITH SOME PACIFIC
MOISTURE...WILL BRING A GOOD CHANCE OF PRECIPITATION TO THE AREA
THU AFTERNOON. ARTHUR
&&
.SHORT TERM...VALID FOR THU AND FRI...
SERIES OF PROGRESSIVE WAVES IN NW FLOW WILL CONTINUE THROUGH THE
SHORT TERM PERIOD...CUTTING OUT STRONG CYCLONIC FLOW OVER US BY
FRIDAY. THIS WILL BRING PERIODS OF RAIN/SNOW/GRAUPEL SHOWERS. THE
BEST CHANCE OF ACCUMULATING SNOW IS THURSDAY NIGHT INTO FRIDAY.
SEVERAL INCHES OF SNOW MAY PILE UP ALONG NORTH FACING SLOPES IN
THE HIGH COUNTRY AND POSSIBLY THE FOOTHILLS. TEMPERATURES AT FIRST
GLANCE LOOK TO WARM FOR ACCUMULATION AT THE LOWER ELEVATIONS
INCLUDING BILLINGS. HOWEVER...BUFKIT SOUNDINGS /WETBULB/ SUPPORT A
CHANGE OVER TO SNOW OVER THE PLAINS LATE THURSDAY EVENING...AND
COLD AIR GETS PULLED DOWN FROM THE NORTH BY FRIDAY MORNING.
THUS...SOME ACCUMULATION OVER THE PLAINS IS POSSIBLE THROUGH
FRIDAY...BUT MAY NOT STICK TO ROADS. AT THIS POINT...HARD TO
PINPOINT ANY AREA THAT WOULD DEFINITELY REQUIRE HIGHLIGHTS...BUT
WE MAY NEED ADVISORIES FOR FOOTHILLS AGAIN BY THURSDAY NIGHT. BT
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
LONG TERM OUTLOOK IS FAIRLY UNCHANGED THROUGH MOST OF THE PERIOD.
THOUGH THE FORECAST TURNS INTERESTING NEXT WEEK AS ANOTHER SPRING
STORM COULD IMPACT THE REGION TUESDAY INTO WEDNESDAY.
THE WEEKEND BEGINS MILD AND MOSTLY DRY AS WEAK RIDGING MOVES INTO
THE FORECAST AREA LATE SATURDAY EVENING. AHEAD OF THIS RIDGING
WEAK INSTABILITY COULD BRING ISOLATED SHOWERS TO THE AREA...THOUGH
MOSTLY OVER THE HIGHER ELEVATIONS. TEMPERATURES WILL BE AROUND 50
ON SATURDAY AND THEN WARM UP INTO THE UPPER 50S SUNDAY.
CONDITIONS BEGIN TO GROW UNSETTLED ON MONDAY EVENING AS A WESTERN
CONUS TROUGH DEEPENS AT THE BEGINNING OF THE WEEK. FOR NOW IT
APPEARS WE COULD SEE SHOWERS AND RAIN MOVING IN MONDAY EVENING
FOLLOWED BY A CHANCE FOR SNOW TUESDAY AND WEDNESDAY AS COOLER
WEATHER SLIDES IN. THERE IS STILL A LOT OF UNCERTAINTY IN SNOW
AMOUNTS AS THESE WILL VARY WITH THE EVENTUAL PATH OF THE UPPER
LEVEL LOW. REGARDLESS...THERE IS GOOD CONFIDENCE IN COOLER
CONDITIONS MOVING IN NEXT WEEK. DOBBS
&&
.AVIATION...
ISOLATED LIGHT RAIN/SNOW SHOWERS WILL IMPACT THE REGION TONIGHT.
VFR WILL PREVAIL AT LOWER ELEVATIONS...BUT THE HIGH TERRAIN MAY BE
OBSCURED AT TIMES. ON THURSDAY...A PACIFIC DISTURBANCE WILL BRING
A GOOD CHANCE OF SHOWERS BEGINNING BY MIDDAY IN THE WEST THEN
ACROSS THE AREA DURING THE AFTERNOON AND EVENING. EXPECT AREAS OF
MVFR CONDITIONS ACROSS THE PLAINS AND FREQUENT MOUNTAIN
OBSCURATIONS. SW-W WINDS WILL BE GUSTY ALONG THE WESTERN FOOTHILLS
LATE TONIGHT AND TOMORROW. JKL
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 033/054 033/044 023/049 028/056 034/053 034/047 030/046
25/W 45/O 20/B 10/B 11/E 24/W 33/W
LVM 030/050 028/043 019/044 026/051 031/049 028/043 024/042
27/W 36/O 30/B 11/N 12/W 34/W 43/W
HDN 027/056 031/044 018/049 023/058 029/058 031/051 028/048
24/W 66/O 20/B 10/U 11/B 23/W 33/W
MLS 030/058 033/040 020/048 027/059 031/061 033/055 030/049
22/W 36/O 10/B 10/U 01/B 12/W 32/W
4BQ 027/057 031/043 019/046 024/057 028/062 031/054 029/047
22/W 55/O 20/B 10/U 01/B 12/W 33/W
BHK 026/056 031/040 017/043 023/056 027/059 030/054 029/046
11/B 24/O 10/B 10/U 01/B 12/W 33/W
SHR 024/052 027/043 015/043 020/052 025/056 031/048 027/042
22/W 55/O 30/B 10/U 11/B 24/W 44/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
711 PM CDT WED MAR 23 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 342 PM CDT WED MAR 23 2016
THE SLOWER RAP MODEL AND HRRR MODEL ARE PREFERRED WHICH CONTINUE
SNOW CONTINUING IN EASTERN AREAS FOR A FEW HOURS AFTER MIDNIGHT.
THE BETTER GUESS IS WHEN THE THIRD OF THREE SNOW BANDS DEVELOPS
LATER TONIGHT ACROSS CENTRAL NEBRASKA...THE SECOND ONGOING SNOW
BAND WILL FALL APART.
THE FORECAST BLENDS SOME OF THE SLOWER RAPID UPDATE MODELS WITH
THE PREVIOUS FORECAST WHICH ADDS AN INCH OR TWO SNOW ACCUMULATION
ACROSS SWRN NEB AND PARTS OF THE CENTRAL SANDHILLS. GIVEN THE
WARM GROUND AND SNOWFALL RATES OF AN INCH OR LESS PER HOUR THUS
FAR...FORECAST ACCUMULATIONS COULD ACTUALLY BE TOO HIGH IN THE
LOWER ELEVATIONS.
WIND GUSTS OF 50 TO 55 MPH SHOULD CONTINUE IN THE OPEN AREAS
EARLY THIS EVENING AND THEN DROP OFF. EARLIER GUSTS OF 60 TO 64
MPH HAVE VANISHED. MOST OF THOSE GUSTS WERE MOMENTUM TRANSPORT
FROM 65 KT WINDS AT 3KFT PER KLNX VWP SO THE GUSTS ARE AT THE
MERCY OF VERTICAL MIXING.
SKIES BY MORNING SHOULD BE GENERALLY CLEAR WITH DRIER AIR MOVING
IN AT ALL LEVELS. THE LOWS IN THE TEENS AND LOWER 20S ARE MODEST.
WINDS ALOFT WOULD CONTINUE STRONG PREVENTING A DEEP INVERSION IN
MOST AREAS. THE EXCEPTION IS THE WRN SANDHILLS WHERE SINGLE OR
NEAR SINGLE DIGITS AREA EXPECTED.
ALL FORECAST HIGHLIGHTS WILL OPERATE IN PLACE. NO UPGRADES APPEAR
TO BE NEEDED AT THIS TIME AS THE SYSTEM HAS GENERALLY BEEN WELL-
BEHAVED. THERE IS STILL ROOM FOR A SURPRISE GIVEN THE STRENGTH OF
THIS STORM.
LASTLY...THE OCCASIONAL LIGHTNING AND THUNDERSTORMS ARE THE
RESULT OF ELEVATED CAPE. THE RAP HAS SHOWN ONLY WEAK SKILL WITH
THIS FEATURE. THE 750MB BARRIER JET IS QUITE STRONG.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM CDT WED MAR 23 2016
A LOW PRESSURE SYSTEM WILL PUSH ACROSS THE NORTHERN PLAINS
THURSDAY NIGHT AND FRIDAY...DRAGGING A COLD FRONT ACROSS THE AREA
LATE IN THE DAY ON FRIDAY. A SLIGHT WARM UP TO AROUND 50 AHEAD OF
THE FRONT. MOISTURE IS LIMITED...HOWEVER MODELS MAY BE UNDERDONE
ON WHAT IS AVAILABLE IN THE BOUNDARY LAYER DUE TO EXPECTED SNOW
MELT/EVAPORATION FROM PRECIP FROM ONGOING STORM. THAT
SAID...MODELS FOCUS MOST OF THE ENERGY ACROSS THE NORTH...WITH
POCKETS ACROSS THE CWA. THUS WILL CONTINUE TO HAVE LOW POPS.
TEMPS COOL OFF BEHIND THE FRONT WITH RAIN POSSIBLY MIXING WITH
SNOW INTO FRIDAY NIGHT. MOST AREAS WILL BE DRY BY
SATURDAY...HOWEVER THE WESTERN SIDE OF THE FRONT STALLS NEAR THE
NEB/KS BORDER AND COLD LINGER SOME RAIN/SNOW ACROSS FAR
SOUTHWESTERN NEB INTO SATURDAY. COLD AIR IS DRAWN IN BEHIND THE
FRONT WITH HIGHS ONLY AROUND 40 FOR SATURDAY. A GOOD 10 TO 15
DEGREES BELOW NORMAL FOR THE LAST WEEK OF MARCH.
WARM FRONT TO PUSH ACROSS THE AREA WITH A WARM UP FOR EASTER
SUNDAY. HIGHS BACK CLOSER TO NORMAL...50S...AND DRY. EVEN
WARMER...60S...FOR MONDAY INTO TUESDAY. THEN THE NEXT SYSTEM
EJECTS ONTO THE PLAINS FOR MID WEEK...AND BRING ANOTHER CHANCE
FOR RAIN/SNOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 638 PM CDT WED MAR 23 2016
BLIZZARD CONDITIONS CONTINUE AT THE KLBF TERMINAL AND VICINITY
WITH WINDS 36035G45KT AND VSBY NEAR 1/4SM AT TIMES. THERE WILL BE
A GRADUAL IMPROVEMENT TO MVFR CONIDITIONS BY 02Z...THEN VFR BY
AROUND 06Z. VFR CONDITIONS AT THE KVTN TERMINAL TO CONTINUE. A
LARGE AREAS OF SNOW CONTINUED FROM SOUTHWEST INTO NORTH CENTRAL
AND NORTHEAST NEBRASKA. THIS SNOW WILL END FROM WEST TO EAST
OVERNIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 AM CDT /MIDNIGHT MDT/ THURSDAY FOR
NEZ006>010-025>029-036>038-057>059-069-070.
WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING
FOR NEZ004-094.
WINTER STORM WARNING UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR
NEZ005-022>024-035-056.
WINTER WEATHER ADVISORY UNTIL 1 AM CDT THURSDAY FOR NEZ071.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS RALEIGH NC
758 PM EDT WED MAR 23 2016
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL EXTEND ACROSS THE SOUTHEASTERN UNITED
STATES UNTIL A COLD FRONT CROSSES THE REGION ON FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 235 PM WEDNESDAY...
BERMUDA HIGH PRESSURE EXTENDS ACROSS THE SOUTHEAST US TODAY WITH A
WARM SOUTHERLY WIND THAT IS GUSTING TO 20-25KT PRETTY MUCH AS
FORECAST. RAP SOUNDINGS WERE ALL OVER THE LOWER DEWPOINTS IN THE
WESTERN PIEDMONT THIS MORNING WITH SEVERAL MID-20S BEING
REPORTED...LEADING TO MINIMUM RH VALUES OF 18-22%. WIND GUSTS HAVE
BEEN STRONGEST OVER THE SOUTHERN PIEDMONT AND SANDHILLS...SO THE
INCREASED FIRE DANGER STATEMENT HAS WORKED OUT WELL FROM THE
CRITERION STAND POINT. THE IFD STATEMENT WILL EXPIRE AT 9PM.
A LIGHT 3-6KT WIND WILL CONTINUE OVERNIGHT AND SHOULD PREVENT FOG
FROM DEVELOPMENT...WITH NAM/GFS FORECAST SOUNDINGS SUGGESTING THE
BEST CHANCE OF STRATUS ACROSS THE SOUTHERN PIEDMONT...THOUGH EVEN
THOUGH SATURATION IS NEVER QUITE REALIZED. LOWS WILL BE IN THE
UPPER 40S AND LOWER 50S.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
AS OF 235 PM WEDNESDAY...
ANOTHER WARM DAY ON THURSDAY AS THE BERMUDA HIGH HOLDS AND
SOUTHWESTERLY FLOW CONTINUES. HIGH CLOUDS WILL BEGIN TO SPILL IN
FROM THE WEST AHEAD OF THE UPPER LOW LIFTING THROUGH THE
MIDWEST...AND INCREASING LOW-LEVEL MOISTURE WILL LEAD TO SCATTERED
CU DURING THE AFTERNOON. A STRONG CAPPING INVERSION WILL SQUELCH ANY
CONVECTION...EVEN THOUGH A COUPLE HI-RES WRFS SHOW ISOLATED ACTIVITY
IN THE SOUTHEAST ALONG A SEABREEZE. H10-H85 THICKNESSES ONLY BUMP UP
ABOUT 5M...SO WE SHOULD BE WITHIN A DEGREE OR TWO OF TODAYS
HIGHS...74-79.
AS THE AFOREMENTIONED UPPER LOW SHEARS AND LIFTS THROUGH THE MIDWEST
AND GREAT LAKES...A TRAILING COLD FRONT AND CONVECTION WILL MOVE
INTO THE TENN VALLEY THURSDAY AFTERNOON AND EVENTUALLY CROSS THE
MOUNTAINS THURSDAY EVENING. MODELS HAVE SLOWED RATHER SIGNIFICANTLY
WITH THE ARRIVAL OF THE MERGING PRE-FRONTAL TROUGH AND COLD
FRONT...SUCH THAT AT LEAST THE FIRST HALF OF THURSDAY NIGHT IS
COMPLETELY DRY. HAVE CUT BACK LIKELY POPS SIGNIFICANTLY PRIOR TO
06Z..AND MAYBE NOT ENOUGH BETWEEN 06Z-12Z GIVEN THE 12Z ECMWF RUN.
UPPER LEVEL FORCING WILL BE MOSTLY WEAK BY THE TIME THE FRONT GETS
HERE...WITH THE MAIN DCVA WELL OFF TO THE BOTH AND A RELATIVELY WEAK
(RIGHT ENTRANCE) UPPER JET. MODELS DO SHOW SOME WEAK
INSTABILITY...MOSTLY ELEVATED OWING TO NOCTURNAL STABILIZATION EARLY
IN THE EVENING...SO ANY ISOLATED STORM OR TWO MAY BE POSSIBLE...WITH
BETTER CHANCES POSSIBLY ON FRIDAY INT HE EAST IF THE SYSTEM IS
INDEED SLOWER. LOWS WILL BE QUITE A BIT MILDER...55-62
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 230 PM WEDNESDAY...
FRIDAY AND FRIDAY NIGHT...COLD FRONT WILL BE MOVING ACROSS AND EAST
OF THE AREA EARLY FRIDAY...BECOMING ALIGNED PARALLEL TO THE
PREVAILING FLOW AND STALLING IN THE VICINITY OF THE COAST EARLY
FRIDAY NIGHT. WILL SHOW A TREND FROM LIKELY POPS IN THE MORNING
TAPERING OFF PROGRESSIVELY FROM THE WEST TO A SLIGHT CHANCE EAST OF
I95 BY EARLY (00Z) FRIDAY NIGHT. CONVECTIVE POTENTIAL WILL BE
STRONGEST IN THE EAST WHERE THE TIMING OF STRONGEST LOW LEVEL LIFT
WILL BE COINCIDENT WITH CAPES APPROACHING 1K JOULES IN THE EARLY
AFTERNOON (PRIMARILY DUE TO STEEP MID LEVEL LAPSE RATES ON THE ORDER
OF 6.5C/KM). LOW LEVEL SHEAR LOOKS TO BE RATHER UNIMPRESSIVE AND MID
LEVEL FORCING MINIMAL AS THE UPPER SHORT WAVE WILL BE DISPLACED WELL
NORTH OVER THE GREAT LAKES. DELAY OF COOL AIR ADVECTION WILL ALLOW
HIGHS TO REACH 70 TO 75 AND EVEN THE NORTHWEST WILL REACH UPPER 60S
DESPITE EARLIER FRONTAL PASSAGE AS THEY WILL SEE CLEARING AND HAVE
SOME TIME TO WARM BEFORE COOL AIR GAINS THE UPPER HAND. LINGERING
CLOUDINESS IN THE EAST WILL CLEAR FRIDAY NIGHT AS THE COOLER AND
DRIER AIRMASS RADIATES DOWN INTO THE 40 TO 45 RANGE OVER MOST OF THE
AREA BY MORNING...EXCEPT FOR THE SOUTHEAST WHICH WILL BE MOSTLY IN
THE UPPER 40S DUE TO THE EARLY CLOUDINESS AND MIXING TO DELAY THE
DIURNAL CRASH.
FOR THE WEEKEND AND EARLY NEXT WEEK...A PROGRESSIVE HIGH MOVING
ACROSS THE GREAT LAKES WILL MAINTAIN DRY AND SEASONABLY COOL AIR
OVER US ON SATURDAY. HOWEVER...THE FRONTAL ZONE ALONG THE COAST ADDS
SOME UNCERTAINTY TO THE MID TO LATE WEEKEND AS ITS PROXIMITY TO THE
COAST AND SUBSEQUENT POTENTIAL FOR SURFACE WAVE DEVELOPMENT ALONG
THE FRONT COULD PRODUCE CLOUDINESS AND POSSIBLY SOME SHOWERS ACROSS
THE SOUTH AND EAST AS EARLY AS SATURDAY NIGHT...BUT MORE LIKELY LATE
SUNDAY INTO SUNDAY NIGHT. HIGHS SATURDAY WILL BE MOSTLY MID TO UPPER
60S...WITH INCREASING CLOUDINESS BUT SOME WEAK WARM AIR ADVECTION AS
WINDS VEER AROUND TO EAST/SOUTHEAST AS THE SURFACE HIGH WEAKENS AND
LIFTS NORTHEAST. SHOWERS/LIGHT RAIN WILL SPREAD ACROSS THE
AREA...BECOMING FAIRLY WIDESPREAD BY LATE SUNDAY NIGHT THROUGH
MONDAY AFTERNOON IN THE WARM AIR ADVECTIVE REGIME AHEAD OF AN
APPROACHING COLD FRONT. STILL UNCERTAINTY IN HOW FAST THIS FRONT
WILL SWEEP THROUGH...BUT LATEST TRENDS ARE FASTER...AND SHOWERS
WOULD BE TAPERING OFF QUICKLY IN THE WEST AND ENDING BY MONDAY
EVENING IN THE EAST. HIGHS MONDAY WILL BENEFIT FROM THE WARM AIR
ADVECTION TO REACH THE UPPER 60S TO LOW 70S.
DRY AND SEASONABLE CONDITIONS ARE EXPECTED FROM MONDAY NIGHT THROUGH
WEDNESDAY AS SKIES CLEAR AND MILD HIGH PRESSURE BUILDS BACK IN
BEHIND MONDAYS COLD FRONT. WITH COOL AIR SETTLING IN PLACE...LOWS
MONDAY AND TUESDAY NIGHT WILL BE IN THE 40S...WITH HIGHS TUESDAY AND
WEDNESDAY IN THE LOW TO MID 60S.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 755 PM WEDNESDAY...
UNDER THE INFLUENCE OF MODIFIED CONTINENTAL POLAR HIGH PRESSURE NOW
CENTERED NEAR BERMUDA --AND WITH AN ASSOCIATED LASTING IMPACT OF
VERY DRY AIR IT LEFT BEHIND-- VFR CONDITIONS WILL RESULT THROUGHOUT
CENTRAL NC THROUGH THE TAF PERIOD. WHILE THAT AIR MASS WILL
PROGRESSIVELY MODIFY AS RETURN SOUTHERLY/FLOW AROUND THE HIGH YIELDS
GRADUALLY INCREASING AMOUNTS OF LOW LEVEL MOISTURE...THE ANTECEDENT
DRYNESS WILL LIKELY SUPPORT ONLY PATCHES OF LOW STRATUS (AROUND 500
FT) AROUND 12Z THU IN THE VICINITY OF FAY/RDU/RWI....AND PERHAPS
SOME ACCOMPANYING MARGINALLY REDUCED VISIBILITY IN LIGHT FOG AT THE
LATTER TWO SITES.
OTHERWISE...A LIGHT SSW WIND TONIGHT WILL BECOME BREEZY WITH THE
EROSION OF THE NOCTURNAL INVERSION BY 16Z THU...AND SUBSEQUENTLY BE
CHARACTERIZED BY SUSTAINED SPEEDS IN THE 10-15 KT RANGE WITH GUSTS
20-25 KTS THU AFTERNOON. FLAT CUMULUS WITH BASES AROUND 5 THOUSAND
FT WILL SCATTER THE AFTERNOON SKY AMIDST OTHERWISE PASSING HIGH
CIRRUS.
OUTLOOK: SHOWERS AND AN ACCOMPANYING BAND OF IFR-MVFR CEILINGS ALONG
AND AHEAD OF A COLD FRONT WILL ARRIVE AT WESTERN TAF SITES LATE THU
NIGHT-FRI MORNING...BEFORE MOVING EAST ACROSS THE REMAINDER OF
CENTRAL NC DURING THE DAY FRI. A FEW STORMS MAY ACCOMPANY THE
SHOWERS AT RWI AND FAY FRI AFTERNOON...WHERE DIURNAL TIMING WILL BE
MORE FAVORABLE FOR THE DEVELOPMENT OF...ALBEIT WEAK...INSTABILITY.
MVFR CEILINGS MAY LINGER OR RE-DEVELOP OVER EASTERN NC...INCLUDING
AS FAR WEST AS RWI AND FAY...AS THE FRONT STALLS ALONG THE COAST BY
SAT MORNING. A CHANCE OF RAIN AND SUB-VFR CONDITIONS WILL BE
POSSIBLE AREA-WIDE ON SUNDAY...AS ANOTHER FRONTAL SYSTEM MOVES
THROUGH THE MIDDLE ATLANTIC STATES.
&&
.FIRE WEATHER...
AS OF 335 AM WEDNESDAY...
AN INCREASED FIRE DANGER REMAINS IN EFFECT TODAY FROM UNTIL 9 PM...
DRY AIR WILL HOLD IN PLACE WITH RELATIVE HUMIDITY MOSTLY IN THE 20-
25% RANGE THIS AFTERNOON...THOUGH A FEW AREAS IN THE WESTERN
PIEDMONT HAVE DROPPED TO 10-15%. THIS COMBINED WITH SUSTAINED WINDS
FROM THE SW AROUND 15 KT GUSTING TO NEAR 25 KTS AND LOW FINE FUEL
MOISTURE (STILL JUST 5-6%) WILL CONTINUE THE ELEVATED RISK FOR
ADVERSE FIRE BEHAVIOR THIS AFTERNOON.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...26
NEAR TERM...22
SHORT TERM...22
LONG TERM...MLM
AVIATION...26
FIRE WEATHER...HARTFIELD/22
AREA FORECAST DISCUSSION
NWS BISMARCK ND
932 PM CDT WED MAR 23 2016
.UPDATE...
ISSUED AT 929 PM CDT WED MAR 23 2016
QUIET WEATHER CONTINUES OVER THE AREA. A FEW VERY LIGHT SHOWERS
NOTED OVER CENTRAL MOVING INTO EASTERN MONTANA...THOUGH HAVE KEPT
OUR FORECAST DRY IN LINE WITH LATEST HIGH RES-GUIDANCE AS SHOWERS
MOVE INTO DRIER AIR. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 622 PM CDT WED MAR 23 2016
QUIET WEATHER CONTINUES OVER MUCH OF THE AREA. MAIN CHANGE TO THE
FORECAST FOR EARLY EVENING UPDATE WAS TO INCREASE CLOUD COVER OVER
THE FAR WEST...THOUGH THESE LOW LEVEL CLOUDS CONTINUE TO SLOWLY
ERODE. HIGHER LEVEL CLOUDS WILL START TO MOVE IN LATER THIS
EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 331 PM CDT WED MAR 23 2016
THE MAIN FORECAST CONCERN IN THE SHORT TERM PERIOD WILL BE THE
POSSIBILITY OF CLOUD COVER IN THE WEST LINGERING INTO THE EARLY
EVENING HOURS. ATTENTION THEN SHIFTS TO THURSDAY FOR SOME POSSIBLE
FIRE WEATHER CONCERNS.
CURRENTLY...COOL AND DRY HIGH PRESSURE CENTER WAS OVER SOUTHEASTERN
MANITOBA...WITH A HIGH PRESSURE RIDGE AXIS EXTENDING SOUTHWESTWARD
FROM THE LOW CENTER. THIS DRY AIR CONTINUED TO MOVE WESTWARD
ACROSS NORTH DAKOTA...ERODING THE CLOUD COVER FROM EAST TO WEST. THE
WESTERN THIRD OF THE STATE REMAINS UNDER SOME STRATUS AND MID-LEVEL
CLOUDS. MEANWHILE A VIGOROUS STORM SYSTEM OVER THE CENTRAL AND
SOUTHERN PLAINS CONTINUED TO PRODUCE GUSTY WINDS...RAIN...AND SNOW
FROM COLORADO TO THE GREAT LAKES.
THE SHORT TERM RAP AND HRRR INDICATE THE CLOUDS OVER WESTERN NORTH
DAKOTA SHOULD BECOME SCATTERED LATE THIS AFTERNOON/EARLY EVENING AS
THE DRIER AIR FROM THE HIGH PRESSURE RIDGE AXIS PUSHES WESTWARD.
TONIGHT AND THURSDAY THE CENTRAL PLAINS STORM CENTER MOVES
EAST...THEN NORTHEAST TOWARDS THE GREAT LAKES. THE NORTHWEST FLOW
ALOFT TONIGHT OVER NORTH DAKOTA IS INTERRUPTED BY A SHORTWAVE RIDGE
OVER THE STATE ON THURSDAY. THIS SHORT-LIVED DRYING OF THE LOW/MID
LAYERS WILL PROVIDE A CHANCE FOR A MIX-OUT SURFACE-TO-H800. THIS IS
SUPPORTED BY FORECAST BUFKIT SOUNDINGS AS WELL. THUS USED A BLEND OF
SHORT TERM AND BCCONSMOS FOR MINIMUM RELATIVE HUMIDITY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT WED MAR 23 2016
AN UPPER LEVEL SHORTWAVE OVER THE PACIFIC NORTHWEST TONIGHT MOVES
INTO THE ROCKIES THURSDAY AND INTO THE FRONT RANGE AND WESTERN
DAKOTAS THURSDAY NIGHT. SURFACE LOW PRESSURE DEVELOPS IN RESPONSE
OVER EASTERN MONTANA...WITH COLDER AIR TO THE NORTH IN SOUTHERN
CANADA...AND WARMER AIR TO THE SOUTHWEST OVER WYOMING. A COLD
FRONTAL BOUNDARY DEVELOPS ALONG THE CANADIAN BORDER...WHILE A WARM
FRONT EXTENDING SOUTH FROM THE LOW DEVELOPS THURSDAY NIGHT.
SCATTERED TO ISOLATED AREAS OF RAIN AND SNOW EXPECTED THURSDAY
NIGHT. TEMPERATURE PROFILES SUPPORT WARM AIR ALOFT COINCIDENT WITH
COLDER AIR AT THE SURFACE TO RESULT IN CHANCES OF LIGHT FREEZING
RAIN...MAINLY NORTH CENTRAL COUNTIES THURSDAY NIGHT...AND FOR A
BRIEF HOUR OR TWO POSSIBLE FARTHER SOUTH TOWARDS LAKE SAKAKAWEA AND
INTERSTATE 94 BEFORE/AROUND SUNRISE FRIDAY MORNING.
BY SUNRISE FRIDAY EXPECT SOME LIGHT SNOW ACCUMULATIONS POSSIBLE
ALONG THE CANADIAN BORDER.
FRIDAY AND FRIDAY NIGHT THE UPPER LEVEL SHORTWAVE MOVES SOUTHEAST
ACROSS THE DAKOTAS. THE SURFACE LOW IS FORECAST TO MOVE INTO EASTERN
NORTH DAKOTA BY NOON ON FRIDAY...WITH COLD ADVECTION ALREADY TAKING
PLACE OVER NORTHERN AND INTO SOUTHWESTERN NORTH DAKOTA. INCREASING
CHANCES OF RAIN FRIDAY WITH HIGH CHANCES OF LIGHT SNOW NORTH AND
LIGHT RAIN SOUTH. EXPECT AROUND AN INCH OF SNOW ACCUMULATION DURING
THE DAYTIME FRIDAY. BY FRIDAY NIGHT THE BETTER CHANCES OF
PRECIPITATION ARE ACROSS SOUTHERN NORTH DAKOTA. RAIN CHANGING TO
SNOW WITH A FEW TENTHS OF AN INCH TO 1 INCH OF SNOW POSSIBLE ACROSS
SOUTHERN COUNTIES.
IN SUMMARY...CHANCES OF RAIN AND SNOW THURSDAY NIGHT THROUGH FRIDAY
NIGHT...WITH SOME AREAS OF FREEZING RAIN NORTH CENTRAL LATE THURSDAY
NIGHT INTO EARLY FRIDAY MORNING. SNOW AMOUNTS OF UP TO AN INCH
POSSIBLE...MAINLY ACROSS THE NORTH AND SOUTH CENTRAL...BY DAYBREAK
SATURDAY.
MAINLY DRY FOR THE WEEKEND INTO EARLY NEXT WEEK WITH A SLOW WARMING
TREND.
THE MEDIUM RANGE MODELS ARE STILL IN DISAGREEMENT REGARDING A STORM
SYSTEM FOR NEXT WEEK...BUT THE LATEST 12Z RUNS ARE SHOWING A
POSSIBLE TREND TOWARD BETTER AGREEMENT. THE STORM SYSTEM IS
FORECAST TO DEVELOP FROM A LONGWAVE TROUGH OVER
THE WEST COAST SUNDAY...DEEPENING OVER THE ROCKIES
MONDAY/TUESDAY...AND EXPANDING INTO THE PLAINS TUESDAY
NIGHT/WEDNESDAY WITH THE LONGWAVE TROUGH REMAINING OVER THE CONUS
THROUGH MUCH OF NEXT WEEK. THE GFS HAS BEEN BULLISH ON DEVELOPING
A LARGE STORM SYSTEM REACHING WELL INTO THE NORTHERN PLAINS THAT
WOULD BRING WIDESPREAD RAIN AND SNOW TO NORTH DAKOTA. THE ECMWF IS
NOW DEPICTING A STRONGER SHORTWAVE EJECTING OUT OF THE BASE OF THE
LOW THAT IN TURN DEVELOPS A SURFACE LOW IN A REASONABLY SIMILAR
PLACE IN THE MISSOURI AND UPPER MISSISSIPPI VALLEY. CHANCES OF RAIN
OR SNOW REMAIN IN THE FORECAST FOR TUESDAY/WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 622 PM CDT WED MAR 23 2016
LCL MVFR CIGS POSSIBLE EARLY THIS EVENING OVER FAR WESTERN NORTH
DAKOTA. OTHERWISE...VFR CONDITIONS EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...JV
LONG TERM...JV
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
633 PM CDT WED MAR 23 2016
.UPDATE...
ISSUED AT 622 PM CDT WED MAR 23 2016
QUIET WEATHER CONTINUES OVER MUCH OF THE AREA. MAIN CHANGE TO THE
FORECAST FOR EARLY EVENING UPDATE WAS TO INCREASE CLOUD COVER OVER
THE FAR WEST...THOUGH THESE LOW LEVEL CLOUDS CONTINUE TO SLOWLY
ERODE. HIGHER LEVEL CLOUDS WILL START TO MOVE IN LATER THIS
EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 331 PM CDT WED MAR 23 2016
THE MAIN FORECAST CONCERN IN THE SHORT TERM PERIOD WILL BE THE
POSSIBILITY OF CLOUD COVER IN THE WEST LINGERING INTO THE EARLY
EVENING HOURS. ATTENTION THEN SHIFTS TO THURSDAY FOR SOME POSSIBLE
FIRE WEATHER CONCERNS.
CURRENTLY...COOL AND DRY HIGH PRESSURE CENTER WAS OVER SOUTHEASTERN
MANITOBA...WITH A HIGH PRESSURE RIDGE AXIS EXTENDING SOUTHWESTWARD
FROM THE LOW CENTER. THIS DRY AIR CONTINUED TO MOVE WESTWARD
ACROSS NORTH DAKOTA...ERODING THE CLOUD COVER FROM EAST TO WEST. THE
WESTERN THIRD OF THE STATE REMAINS UNDER SOME STRATUS AND MID-LEVEL
CLOUDS. MEANWHILE A VIGOROUS STORM SYSTEM OVER THE CENTRAL AND
SOUTHERN PLAINS CONTINUED TO PRODUCE GUSTY WINDS...RAIN...AND SNOW
FROM COLORADO TO THE GREAT LAKES.
THE SHORT TERM RAP AND HRRR INDICATE THE CLOUDS OVER WESTERN NORTH
DAKOTA SHOULD BECOME SCATTERED LATE THIS AFTERNOON/EARLY EVENING AS
THE DRIER AIR FROM THE HIGH PRESSURE RIDGE AXIS PUSHES WESTWARD.
TONIGHT AND THURSDAY THE CENTRAL PLAINS STORM CENTER MOVES
EAST...THEN NORTHEAST TOWARDS THE GREAT LAKES. THE NORTHWEST FLOW
ALOFT TONIGHT OVER NORTH DAKOTA IS INTERRUPTED BY A SHORTWAVE RIDGE
OVER THE STATE ON THURSDAY. THIS SHORT-LIVED DRYING OF THE LOW/MID
LAYERS WILL PROVIDE A CHANCE FOR A MIX-OUT SURFACE-TO-H800. THIS IS
SUPPORTED BY FORECAST BUFKIT SOUNDINGS AS WELL. THUS USED A BLEND OF
SHORT TERM AND BCCONSMOS FOR MINIMUM RELATIVE HUMIDITY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT WED MAR 23 2016
AN UPPER LEVEL SHORTWAVE OVER THE PACIFIC NORTHWEST TONIGHT MOVES
INTO THE ROCKIES THURSDAY AND INTO THE FRONT RANGE AND WESTERN
DAKOTAS THURSDAY NIGHT. SURFACE LOW PRESSURE DEVELOPS IN RESPONSE
OVER EASTERN MONTANA...WITH COLDER AIR TO THE NORTH IN SOUTHERN
CANADA...AND WARMER AIR TO THE SOUTHWEST OVER WYOMING. A COLD
FRONTAL BOUNDARY DEVELOPS ALONG THE CANADIAN BORDER...WHILE A WARM
FRONT EXTENDING SOUTH FROM THE LOW DEVELOPS THURSDAY NIGHT.
SCATTERED TO ISOLATED AREAS OF RAIN AND SNOW EXPECTED THURSDAY
NIGHT. TEMPERATURE PROFILES SUPPORT WARM AIR ALOFT COINCIDENT WITH
COLDER AIR AT THE SURFACE TO RESULT IN CHANCES OF LIGHT FREEZING
RAIN...MAINLY NORTH CENTRAL COUNTIES THURSDAY NIGHT...AND FOR A
BRIEF HOUR OR TWO POSSIBLE FARTHER SOUTH TOWARDS LAKE SAKAKAWEA AND
INTERSTATE 94 BEFORE/AROUND SUNRISE FRIDAY MORNING.
BY SUNRISE FRIDAY EXPECT SOME LIGHT SNOW ACCUMULATIONS POSSIBLE
ALONG THE CANADIAN BORDER.
FRIDAY AND FRIDAY NIGHT THE UPPER LEVEL SHORTWAVE MOVES SOUTHEAST
ACROSS THE DAKOTAS. THE SURFACE LOW IS FORECAST TO MOVE INTO EASTERN
NORTH DAKOTA BY NOON ON FRIDAY...WITH COLD ADVECTION ALREADY TAKING
PLACE OVER NORTHERN AND INTO SOUTHWESTERN NORTH DAKOTA. INCREASING
CHANCES OF RAIN FRIDAY WITH HIGH CHANCES OF LIGHT SNOW NORTH AND
LIGHT RAIN SOUTH. EXPECT AROUND AN INCH OF SNOW ACCUMULATION DURING
THE DAYTIME FRIDAY. BY FRIDAY NIGHT THE BETTER CHANCES OF
PRECIPITATION ARE ACROSS SOUTHERN NORTH DAKOTA. RAIN CHANGING TO
SNOW WITH A FEW TENTHS OF AN INCH TO 1 INCH OF SNOW POSSIBLE ACROSS
SOUTHERN COUNTIES.
IN SUMMARY...CHANCES OF RAIN AND SNOW THURSDAY NIGHT THROUGH FRIDAY
NIGHT...WITH SOME AREAS OF FREEZING RAIN NORTH CENTRAL LATE THURSDAY
NIGHT INTO EARLY FRIDAY MORNING. SNOW AMOUNTS OF UP TO AN INCH
POSSIBLE...MAINLY ACROSS THE NORTH AND SOUTH CENTRAL...BY DAYBREAK
SATURDAY.
MAINLY DRY FOR THE WEEKEND INTO EARLY NEXT WEEK WITH A SLOW WARMING
TREND.
THE MEDIUM RANGE MODELS ARE STILL IN DISAGREEMENT REGARDING A STORM
SYSTEM FOR NEXT WEEK...BUT THE LATEST 12Z RUNS ARE SHOWING A
POSSIBLE TREND TOWARD BETTER AGREEMENT. THE STORM SYSTEM IS
FORECAST TO DEVELOP FROM A LONGWAVE TROUGH OVER
THE WEST COAST SUNDAY...DEEPENING OVER THE ROCKIES
MONDAY/TUESDAY...AND EXPANDING INTO THE PLAINS TUESDAY
NIGHT/WEDNESDAY WITH THE LONGWAVE TROUGH REMAINING OVER THE CONUS
THROUGH MUCH OF NEXT WEEK. THE GFS HAS BEEN BULLISH ON DEVELOPING
A LARGE STORM SYSTEM REACHING WELL INTO THE NORTHERN PLAINS THAT
WOULD BRING WIDESPREAD RAIN AND SNOW TO NORTH DAKOTA. THE ECMWF IS
NOW DEPICTING A STRONGER SHORTWAVE EJECTING OUT OF THE BASE OF THE
LOW THAT IN TURN DEVELOPS A SURFACE LOW IN A REASONABLY SIMILAR
PLACE IN THE MISSOURI AND UPPER MISSISSIPPI VALLEY. CHANCES OF RAIN
OR SNOW REMAIN IN THE FORECAST FOR TUESDAY/WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 622 PM CDT WED MAR 23 2016
LCL MVFR CIGS POSSIBLE EARLY THIS EVENING OVER FAR WESTERN NORTH
DAKOTA. OTHERWISE...VFR CONDITIONS EXPECTED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...JV
LONG TERM...JV
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1139 PM CDT MON MAR 21 2016
.UPDATE...
ISSUED AT 1000 PM CDT MON MAR 21 2016
...UPDATED FOR AVIATION DISCUSSION...
CURRENT RADAR AND GROUND TRUTH DATA SHOWING LIGHT SNOW OVER MAINLY
BENSON...TOWNER AND RAMSEY COUNTIES. THIS CURRENT BAND LINES UP
FAIRLY WELL (ALTHOUGH SPATIALLY JUST NORTH OF) A BAND OF MID LEVEL
FG FORCING DEPICTED ON THE 00Z NAM. NAM INTENSIFIES THIS BAND
AROUND 03Z HOWEVER BY 06Z IT WEAKENS AND SHIFTS INTO RAMSEY AND
NELSON COUNTIES...WHICH SEEMS REASONABLE BASED ON CURRENT MID
LEVEL FLOW. HRRR QPF STRUGGLES TO GET ANY SIGNIFICANT PRECIP GOING
IN NORTHEAST ND...AND ALTHOUGH THIS IS SIMILAR TO THE NAM
FORCING...IT SEEMS OVERLY DRY AS SOME LIGHT SNOW IS EXPECTED
OUTSIDE OF THIS BAND AND ALONG AND NORTH OF HWY 2. WILL MAKE
ADJUSTMENTS TO POPS AND QPFS...ADDING CATEGORICALS THROUGH 06Z
NORTH OF THE DEVILS LAKER BASIN. EXPECTING A HIGH POP BUT MUCH
LOWER QPF SCENARIO IN THE NORTHERN VALLEY AND NW MINNESOTA. HAVE
INCREASED SNOW AMOUNTS TO AROUND 4 INCHES OF SOUTHERN TOWNER AND
NW RAMSEY. NO OTHER CHANGES PLANNED.
UPDATE ISSUED AT 635 PM CDT MON MAR 21 2016
SWITCHED RADAR TO VCP 31...RESULTING IN BETTER COVERAGE OF LOWER
CLOUDS BY EVEN IN HIGHEST RETURNS VCNTY DVL...WE ARE NOT GETTING
ANY GROUND TRUTH. MAKES SENSE DUE TO THE DRIER AIR WITH THE
EASTERLY FLOW. MAIN QUESTION WILL BE HOW LONG TO DELAY
THINGS...AND WILL START OFF 00Z DRY THEN TREND TOWARD CHANCE POPS
BY 02Z. BEST FG FORCING IS TO THE NORTH AND WEST...SO MAY HAVE TO
DELAY LIKELIES TO THE 04Z TO 06Z TIMEFRAME.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 310 PM CDT MON MAR 21 2016
THE MAIN CHALLENGE WILL BE SNOW POTENTIAL TONIGHT INTO TUESDAY IN
THE NORTH. MODELS ARE IN PRETTY GOOD AGREEMENT...WITH THE LATEST
MESOSCALE MODELS A BIT FURTHER NORTH TONIGHT THAN THE GLOBAL
MODELS.
FOR TONIGHT...SNOW WILL DEVELOP IN THE NORTH NEAR A STRONG
BAROCLINIC ZONE. THE BEST FGEN/ISENTROPIC LIFT REMAINS MAINLY
NORTH OF HIGHWAY 2 TONIGHT...AND THE BEST THREAT FOR 1-3 INCHES
SHOULD OCCUR IN THE FAR NW FA INTO NW MN. GFK WILL BE ON THE
DIVIDING LINE TO SOME MINOR ACCUMULATION AND NOT MUCH AT ALL. THE
TUESDAY MORNING COMMUTE MAY BE SNOW COVERED AND SLICK FOR THE
NORTHERN AREAS...AND WILL HIGHLIGHT THIS IN THE WEATHER STORY. THE
PRECIP MAY START OUT AS SOME RAIN BUT SHOULD QUICKLY GO OVER TO
SNOW PER SOUNDINGS/WET BULB COOLING.
ON TUESDAY...THE BEST DEEP MOISTURE SHOULD MOVE EAST WITH SOME
LIGHT SNOW LINGERING IN THE NORTH. NOT EXPECTING MUCH MORE IN THE
WAY OF ACCUMULATION WITH PERHAPS A FEW TENTHS IN THE MORNING. SOME
LIGHT RAIN COULD MIX IN ONCE TEMPS RISE BY LATE MORNING/EARLY
AFTERNOON.
FOR TUE NIGHT...IT SHOULD BE MAINLY DRY WITH SOME LIGHT SNOW
REMAINING IN THE FAR SOUTHWEST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 310 PM CDT MON MAR 21 2016
ON WED...IT WILL BE DRY AND COOL WITH TEMPS A BIT BELOW NORMAL.
THE LARGER STORM SYSTEM WILL BE TO OUR SOUTH...WITH GENERAL
NORTHERLY FLOW FOR OUR REGION.
FOR THU...EXPECT ANOTHER DRY AND SEASONABLY COOL DAY WITH HIGH
PRESSURE OVER THE REGION. OVERNIGHT LOWS WILL HINGE ON IF WE ARE
CLEAR OR NOT...SO WILL STAY FAIRLY CLOSE TO GUIDANCE AND NOT GO
TOO COLD THU MORNING.
FRIDAY TO MONDAY...MODELS IN PRETTY FAIR AGREEMENT WITH THE
EXTENDED. ONLY CHANCE OF PRECIP FOR THE EASTER WEEKEND APPEARS
CONFINED TO FRIDAY..FRIDAY NIGHT WITH A SHORT WAVE MOVING ACROSS THE
NORTHERN PLAINS BRINGING A RAIN OR SNOW MIX. THEREAFTER NW FLOW AND
SFC HIGH PRESSURE WILL MAKE FOR A DRY AND COOL WEEKEND WITH TEMPS IN
THE MID TO UPPER 30S FOR SATURDAY AND A BIT WARMER ON EASTER SUNDAY
WITH 40S IN THE SOUTH AND WEST. WARMER AIR WITH 500MB RIDGING WORKS
INTO THE AREA TO START THE NEXT WORK WEEK WITH MONDAYS HIGHS
MAINLY IN THE 40S...LOW 50S FOR SE ND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1140 PM CDT MON MAR 21 2016
GFK AND TVF SHOULD SEE MVFR CIGS ADVECT IN OVER THE NEXT COUPLE OF
HOURS AS A BAND OF SNOW MOVES ACROSS REGION. LIGHT SNOW HAS MADE
IT TO THE GRAND FORKS NWS OFFICE BUT WAS NOT RECORDED AT
GFK...HOWEVER AS BAND OVER NELSON CO SHIFTS EAST...STILL EXPECT SN
ON STATION. SHOULD SEE -SN AT TVF AND BJI BY 08Z HOWEVER VSBYS MAY
REMAIN VFR INITIALLY...UNTIL CIGS BEGIN TO FALL AS SN PICKS UP.
EXPECTING SOLID MVFR CIGS BY 09Z AT BOTH MN SITES. SNOW STILL NOT
EXPECTED AT FAR BUT DO THINK MVFR CIGS WILL ARRIVE FOR A BRIEF
PERIOD AROUND 13Z TO 15Z TIMEFRAME. NORTHEAST WINDS WILL BECOME
BREEZY AND REMAIN SO THROUGH 06Z WED.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...DK
LONG TERM...JK/DK
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
738 PM EDT WED MAR 23 2016
.SYNOPSIS...
LOW PRESSURE SYSTEM OVER THE SOUTHERN PLAINS WILL MOVE
ACROSS THE LOWER LAKES THURSDAY AFTERNOON DRAGGING A STRONG COLD FRONT
ACROSS THE FORECAST AREA. HIGH PRESSURE WILL QUICKLY BUILD OVER THE AREA
FRIDAY AND LINGER THROUGH SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
RAIN REMAINS WELL NORTH OF THE AREA AT THIS TIME. LATEST MODELS
SHOW THE POSSIBILITY FOR NEGATIVE VORTICITY ADVECTION EXPECTED
THROUGH THE NIGHT INTO TOMORROW MORNING. I HAVE A SNEAKING HUNCH
THE RAIN MAY HOLD OFF UNTIL TOMORROW. WILL CONTINUE TO MONITOR
RADAR TRENDS TO MAKE A DECISION WHETHER TO PULL OUT THE RAIN FOR
THE OVERNIGHT HOURS WITH THE NEXT UPDATE. REASON FOR HOLDING ON TO
THE RAIN AT THIS TIME IS THE HRRR MODEL STILL BRINGS IN A SHOT OF
RAIN OVERNIGHT FROM WEST TO EAST. OTHERWISE...NO MAJOR CHANGES
WITH THIS UPDATE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
MODELS COMING INTO BETTER AGREEMENT...MOVING THE KANSAS LOW INTO
WEST CENTRAL IL BY DAYBREAK. SHOWERS ACROSS NW OHIO TOMORROW
MORNING WILL BECOME MORE WIDESPREAD IN THE AFTERNOON. A CHANCE FOR
SOME TSRA TOMORROW AFTERNOON AND EVENING. SPC HAS SOUTHWESTERN
PORTION OF THE FORECAST AREA IS MARGINAL FOR SEVERE TSRA. LOW LEVEL
JET DEVELOPS TOMORROW AFTERNOON WITH 925MB WINDS INCREASING TO 40-45
KNOTS IN ADDITION LIFT FROM 300 MB JET MAX. LUCKILY FRONT IS NOT
EXPECTED TO REACH NW OHIO UNTIL TOWARD 00Z SO THERE SHOULD BE
MINIMAL CAPE.
GFS TRACKS THE LOW ACROSS THE CENTRAL LAKES TOMORROW EVENING WHILE
THE NAM IS FURTHER SOUTH. BOTH MODELS HAVE THE FRONT EAST OF THE
AREA TOWARD MIDNIGHT LOCAL. OVERNIGHT TEMPERATURES WILL DROP INTO
THE 30S. RAIN WILL CHANGE TO SNOW OR MIX WITH SNOW LATE TOMORROW
NIGHT. DO NOT EXPECT MUCH IN THE WAY OF ACCUMULATIONS...ESPECIALLY
AS WARM AS THE GROUND IS. COULD SEE A LITTLE LINGERING SNOW IN THE
EAST FRIDAY MORNING...BUT HIGH PRESSURE BUILDS OVER THE AREA QUICKLY
DURING THE DAY. HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH
SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE LONG TERM BEGINS SUNDAY WITH MODELS IN GENERAL AGREEMENT WITH
THE MAJOR PATTERN BUT SIGNIFICANT DIFFERENCES IN THE DETAILS AT
LEAST INITIALLY. MODELS SHOW A BROAD UPPER TROUGH ACROSS THE CENTRAL
STATES WITH A SURFACE LOW OVER THE GREAT LAKES. BY MID WEEK THIS
TROUGH IS REPLACED BY A BROAD UPPER RIDGE. WENT WITH A BLEND OF
GUIDANCE SUNDAY INTO MONDAY. THE BASE OF THE UPPER TROUGH WILL MOVE
ACROSS THE AREA. THE ECMWF AMPLIFIES THE SYSTEM MORE THAN THE GFS
ADVERTISING A MORE DEVELOPED UPPER SYSTEM AS WELL AS A STRONGER
SURFACE LOW. EITHER WAY WILL HAVE CHANCE POPS FOR RAIN SUNDAY
AFTERNOON INCREASING TO LIKELY POPS SUNDAY NIGHT. THE FOCUS OF THE
SYSTEM BEGINS TO SHIFT EAST MONDAY. WILL STILL NEED CHANCE POPS
HOWEVER WITH HIGHEST POPS EAST. TUESDAY AND WEDNESDAY LOOK DRY WITH
THE UPPER RIDGE AND ASSOCIATED SURFACE HIGH BUILDING ACROSS THE
AREA.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
THE SURFACE COLD FRONT REMAINS RAPPED ACROSS THE AREA AND HAS
MADE IT ABOUT AS FAR SOUTH AS IT IS GOING TO GET. IFR CONDITIONS
HAVE DEVELOPED DOWNWIND OF KERI. LITTLE CHANGE IS EXPECTED TILL
WINDS BECOME MORE EASTERLY IN A FEW HOURS. THIS WILL CAUSE CIGS TO
JUMP BACK TO MVFR. ELSEWHERE...A PERIOD OF MVFR CIGS IS EXPECTED
AT ALL OF THE NORTHERN TAF SITES BEGINNING LATE THIS EVENING. DO
EXPECT CIGS TO IMPROVE AGAIN TOWARD DAYBREAK AS THE FRONT MOVES
BACK NORTH AND STRONG SOUTHERLY WINDS DEVELOP. WITH THE EXCEPTION
OF SMALL CHANCES OF PRECIP AT KTOL AND KERI WILL KEEP THE
REMAINDER OF THE AREA DRY OVERNIGHT. PRECIP WILL BEGIN TO SPREAD
INTO THE AREA FROM WEST TO EAST TOMORROW MORNING. EXPECT CIGS TO
DIP BACK TO MVFR ALL AREAS ONCE THE STEADIER PRECIP BEGINS. HAVE
OMITTED ALL MENTION OF THUNDER FOR NOW BUT THAT IS SOMETHING THAT
WILL NEED TO BE LOOKED AT AGAIN. EXPECT SOME SOUTHERLY GUSTS TO 35
KNOTS TOMORROW AFTERNOON...ESPECIALLY IN THE SOUTH.
OUTLOOK...WIDESPREAD NON VFR THURSDAY AFTERNOON AND THURSDAY
NIGHT...LINGERING ACROSS NE OH/NW PA INTO FRIDAY.
&&
.MARINE...
A COLD FRONT NOW SOUTH OF THE LAKE WILL LIFT NORTH AS A WARM FRONT
THURSDAY AHEAD OF LOW PRESSURE APPROACHING FROM THE WEST. A BIT
CONCERNED ABOUT INCREASING ENE WINDS ON THE LAKE THIS EVENING AND
TONIGHT WHICH COULD REACH NEAR 20 KNOTS. GUIDANCE HOWEVER SUGGESTS
THIS WILL REMAIN MAINLY IN THE OFFSHORE WATERS AND THE NORTHERN
PORTION OF THE LAKE. SO FOR NOW NO SMALL CRAFT ADVISORY. WINDS WILL
BE FROM THE SOUTH ON THURSDAY ACROSS THE CENTRAL AND WESTERN PORTION
OF THE LAKE BUT NORTH OF THE NEARSHORE WATERS EAST OF MENTOR WINDS
WILL REMAIN FROM THE EAST. LOW PRESSURE WILL MOVE ACROSS THE LAKE OR
JUST TO THE NORTH ON THURSDAY NIGHT SO EXPECTING WINDS TO BE
VARIABLE. A SMALL CRAFT IS POSSIBLE ON FRIDAY AS WINDS TURN
NORTHWEST BEHIND THE LOW. COLD AIR WILL BE MOVING IN WHICH WILL
LIKELY TRANSFER MORE MOMENTUM TO THE LOWER LEVELS. EXPECTING
NORTHWEST FLOW AROUND 20 KNOTS. SATURDAY EXPECT LIGHT WINDS AS HIGH
PRESSURE BUILDS. SUNDAY WINDS WILL BE LIGHT FROM THE SOUTH AHEAD
OF AN APPROACHING COLD FRONT. MONDAY WINDS WILL TURN NORTHWEST
BEHIND THE FRONT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...LOMBARDY
SHORT TERM...DJB
LONG TERM...TK
AVIATION...KUBINA
MARINE...TK/MULLEN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
651 PM EDT WED MAR 23 2016
.SYNOPSIS...
LOW PRESSURE SYSTEM OVER THE SOUTHERN PLAINS WILL MOVE
ACROSS THE LOWER LAKES THURSDAY AFTERNOON DRAGGING A STRONG COLD FRONT
ACROSS THE FORECAST AREA. HIGH PRESSURE WILL QUICKLY BUILD OVER THE AREA
FRIDAY AND LINGER THROUGH SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
RAIN REMAINS WELL NORTH OF THE AREA AT THIS TIME. LATEST MODELS
SHOW THE POSSIBILITY FOR NEGATIVE VORTICITY ADVECTION EXPECTED
THROUGH THE NIGHT INTO TOMORROW MORNING. I HAVE A SNEAKING HUNCH
THE RAIN MAY HOLD OFF UNTIL TOMORROW. WILL CONTINUE TO MONITOR
RADAR TRENDS TO MAKE A DECISION WHETHER TO PULL OUT THE RAIN FOR
THE OVERNIGHT HOURS WITH THE NEXT UPDATE. REASON FOR HOLDING ON TO
THE RAIN AT THIS TIME IS THE HRRR MODEL STILL BRINGS IN A SHOT OF
RAIN OVERNIGHT FROM WEST TO EAST. OTHERWISE...NO MAJOR CHANGES
WITH THIS UPDATE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
MODELS COMING INTO BETTER AGREEMENT...MOVING THE KANSAS LOW INTO
WEST CENTRAL IL BY DAYBREAK. SHOWERS ACROSS NW OHIO TOMORROW
MORNING WILL BECOME MORE WIDESPREAD IN THE AFTERNOON. A CHANCE FOR
SOME TSRA TOMORROW AFTERNOON AND EVENING. SPC HAS SOUTHWESTERN
PORTION OF THE FORECAST AREA IS MARGINAL FOR SEVERE TSRA. LOW LEVEL
JET DEVELOPS TOMORROW AFTERNOON WITH 925MB WINDS INCREASING TO 40-45
KNOTS IN ADDITION LIFT FROM 300 MB JET MAX. LUCKILY FRONT IS NOT
EXPECTED TO REACH NW OHIO UNTIL TOWARD 00Z SO THERE SHOULD BE
MINIMAL CAPE.
GFS TRACKS THE LOW ACROSS THE CENTRAL LAKES TOMORROW EVENING WHILE
THE NAM IS FURTHER SOUTH. BOTH MODELS HAVE THE FRONT EAST OF THE
AREA TOWARD MIDNIGHT LOCAL. OVERNIGHT TEMPERATURES WILL DROP INTO
THE 30S. RAIN WILL CHANGE TO SNOW OR MIX WITH SNOW LATE TOMORROW
NIGHT. DO NOT EXPECT MUCH IN THE WAY OF ACCUMULATIONS...ESPECIALLY
AS WARM AS THE GROUND IS. COULD SEE A LITTLE LINGERING SNOW IN THE
EAST FRIDAY MORNING...BUT HIGH PRESSURE BUILDS OVER THE AREA QUICKLY
DURING THE DAY. HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH
SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE LONG TERM BEGINS SUNDAY WITH MODELS IN GENERAL AGREEMENT WITH
THE MAJOR PATTERN BUT SIGNIFICANT DIFFERENCES IN THE DETAILS AT
LEAST INITIALLY. MODELS SHOW A BROAD UPPER TROUGH ACROSS THE CENTRAL
STATES WITH A SURFACE LOW OVER THE GREAT LAKES. BY MID WEEK THIS
TROUGH IS REPLACED BY A BROAD UPPER RIDGE. WENT WITH A BLEND OF
GUIDANCE SUNDAY INTO MONDAY. THE BASE OF THE UPPER TROUGH WILL MOVE
ACROSS THE AREA. THE ECMWF AMPLIFIES THE SYSTEM MORE THAN THE GFS
ADVERTISING A MORE DEVELOPED UPPER SYSTEM AS WELL AS A STRONGER
SURFACE LOW. EITHER WAY WILL HAVE CHANCE POPS FOR RAIN SUNDAY
AFTERNOON INCREASING TO LIKELY POPS SUNDAY NIGHT. THE FOCUS OF THE
SYSTEM BEGINS TO SHIFT EAST MONDAY. WILL STILL NEED CHANCE POPS
HOWEVER WITH HIGHEST POPS EAST. TUESDAY AND WEDNESDAY LOOK DRY WITH
THE UPPER RIDGE AND ASSOCIATED SURFACE HIGH BUILDING ACROSS THE
AREA.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
COLD FRONT NOW JUST SOUTH OF A KTOL-KCLE-KLPR-KHZY LINE AT 18Z.
FRONT SHOULD CONTINUE SOUTH INTO THE SECOND COUNTY INLAND AND THEN
STALL THIS AFTERNOON BEFORE LIFTING BACK NORTH EARLY TONIGHT TO
NEAR THE SOUTH SHORE OF THE LAKE. MEANWHILE TO THE WEST THE LOW
WHICH IS KANSAS WILL MOVE ENE TO WESTERN IL BY 12Z AND REACH JUST
NORTH OF LAKE ERIE BY THURSDAY EVENING. THIS WILL LIFT THE FRONT
NORTH OF THE LAKE AS A WARM FRONT. A COLD FRONT EXTENDING SOUTH
FROM THE LOW WILL MOVE IN FROM THE WEST AFTER 18Z.
CONDITIONS VFR AT 18Z BUT EXPECTING HAZE/FOG TO DROP KERI AND
POSSIBLY KCLE AND KTOL TO MVFR. MVFR CIGS ARE STILL NORTH OF THE
AREA AND COULD ALSO GET INTO KTOL AND KERI THIS AFTERNOON BUT
THINKING THERE WILL BE A BETTER CHANCE THIS EVENING AND TONIGHT AS
THE BOUNDARY LAYER COOLS AND MORE MOISTURE MOVES IN. THURSDAY
EXPECTING INCREASING COVERAGE OF MVFR/IFR CONDITIONS AS MOISTURE
INCREASES FURTHER AND COLD FRONT AND SURFACE LOW APPROACH FROM THE
WEST. ALSO EXPECTING SSW WINDS TO BECOME GUSTY WITH GUSTS WELL
INTO THE 20 KNOT RANGE POSSIBLE ESPECIALLY NORTH CENTRAL OHIO AND
POINTS WEST.
OUTLOOK...WIDESPREAD NON VFR THURSDAY AFTERNOON AND THURSDAY
NIGHT...LINGERING ACROSS NE OH/NW PA INTO FRIDAY.
&&
.MARINE...
A COLD FRONT NOW SOUTH OF THE LAKE WILL LIFT NORTH AS A WARM FRONT
THURSDAY AHEAD OF LOW PRESSURE APPROACHING FROM THE WEST. A BIT
CONCERNED ABOUT INCREASING ENE WINDS ON THE LAKE THIS EVENING AND
TONIGHT WHICH COULD REACH NEAR 20 KNOTS. GUIDANCE HOWEVER SUGGESTS
THIS WILL REMAIN MAINLY IN THE OFFSHORE WATERS AND THE NORTHERN
PORTION OF THE LAKE. SO FOR NOW NO SMALL CRAFT ADVISORY. WINDS WILL
BE FROM THE SOUTH ON THURSDAY ACROSS THE CENTRAL AND WESTERN PORTION
OF THE LAKE BUT NORTH OF THE NEARSHORE WATERS EAST OF MENTOR WINDS
WILL REMAIN FROM THE EAST. LOW PRESSURE WILL MOVE ACROSS THE LAKE OR
JUST TO THE NORTH ON THURSDAY NIGHT SO EXPECTING WINDS TO BE
VARIABLE. A SMALL CRAFT IS POSSIBLE ON FRIDAY AS WINDS TURN
NORTHWEST BEHIND THE LOW. COLD AIR WILL BE MOVING IN WHICH WILL
LIKELY TRANSFER MORE MOMENTUM TO THE LOWER LEVELS. EXPECTING
NORTHWEST FLOW AROUND 20 KNOTS. SATURDAY EXPECT LIGHT WINDS AS HIGH
PRESSURE BUILDS. SUNDAY WINDS WILL BE LIGHT FROM THE SOUTH AHEAD
OF AN APPROACHING COLD FRONT. MONDAY WINDS WILL TURN NORTHWEST
BEHIND THE FRONT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...LOMBARDY
SHORT TERM...DJB
LONG TERM...TK
AVIATION...TK
MARINE...TK/MULLEN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
556 AM EDT TUE MAR 22 2016
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE OVER CENTRAL PENNSYLVANIA WILL SLIDE
EAST TO THE MID ATLANTIC COAST BY THIS AFTERNOON.
A WARM FRONT LIFTING SLOWLY NORTH ACROSS THE GREAT LAKES WILL
BRING INCREASING MID AND HIGH LEVEL CLOUDS OVER MOST AREAS OF THE
STATE TODAY...WITH THE CHANCE OF A FEW SHOWERS LIMITED TO FAR
NORTHERN PENNSYLVANIA LATE TODAY AND TONIGHT.
A POTENT AREA OF LOW PRESSURE AND SOUTHWARD TRAILING COLD FRONT
WILL APPROACH FROM THE MISSISSIPPI VALLEY LATE IN THE WEEK...LIKELY
PASSING THROUGH PA LATE THURSDAY INTO FRIDAY...AND BRINGING
PERIODS OF SHOWERS ALONG WITH A CHANCE OF A FEW THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RIDGE OF HIGH PRESSURE OVER THE COMMONWEALTH EARLY TODAY WILL
BRING TRANQUIL BUT CHILLY EARLY SPRING CONDITIONS...WITH SUNRISE
MIN TEMPS RANGING FROM THE UPPER TEENS TO LOWER 20S NORTH...TO
THE MID AND UPPER 20S IN MOST OTHER LOCATIONS.
MID AND HIGH CLOUD SHIELD STREAMING EAST FROM THE WESTERN LAKES
AND OHIO VALLEY REGION WILL SPREAD OVER THE WESTERN HALF OF THE
CWA BY DAYBREAK...BUT MOST OF THE CLOUD COVER THROUGH 12Z WILL
CONSIST OF A VEIL OF THIN CIRRUS...ABOVE SOME SCT ALTO CU.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
HEIGHTS ALOFT WILL CONTINUE TO RISE THROUGH TODAY...BUT OVERALL
THE FLOW ALOFT WILL BECOME QUASI-ZONAL ALLOWING MOISTURE /MAINLY
IN THE FORM OF VARYING AMOUNTS OF ALTO CU AND CIRRUS/ TO SPILL
ESE OVER INTO THE REGION FROM THE GR LAKES AND MIDWEST.
ON THE SURFACE...A DEVELOPING WARM FRONTAL BOUNDARY WILL SNAKE ITS
WAY FROM THE WESTERN GLAKES REGION...EAST TO NEAR THE I-90
CORRIDOR IN CENTRAL NEW YORK.
THE PRIMARY WEST TO SWRLY LOW-MID LEVEL ISENTROPIC LIFT OVER THIS
WARM FRONT WILL BE WELL NORTH OF THE REGION...WHICH WILL CONFINE
THE SOUTHERN EDGE OF ANY LIGHT SHOWERS TO I-86 OR POINTS NORTH IN
SOUTHERN AND WESTERN NEW YORK STATE.
HOWEVER...07Z HRRR IS BONE DRY THROUGH LATE TODAY...AND THE 00Z
NAM AND 03Z SREF CONTINUE THE ABSENCE OF ANY QPF THROUGH AT LEAST
WEDNESDAY MORNING.
IT WILL BE MILDER THAN MONDAY...BY 12-15 DEG F ON AVERAGE...AS
THE HIGH SLIPS OFF THE COAST AND OUR LOW LEVEL FLOW BACKS FROM
WEST TO SOUTHWEST AT 5-10 KTS. EXPECT MID TO LATE AFTERNOON TEMPS
TO RANGE FROM THE L-M 50S ACROSS THE NRN MTNS WHERE THICKER CLOUD
COVER WILL BE PRESENT...TO THE LOWER 60S THROUGHOUT THE SOUTHERN
TIER VALLEYS. VERTICAL MIXING UP TO AROUND 5 KFT AGL THIS
AFTERNOON WILL BRING GUST POTENTIAL IN THE TEENS TO LOWER 20 KT
RANGE.
MILDER TEMPS FOR TONIGHT UNDER VARIABLE AMOUNTS OF MID CLOUDS.
LOWS WILL A FEW TO SVRL DEG F ABOVE NORMAL...OR IN THE UPPER 30S
TO LOWER 40S.
A FEW DEG F INCREASE IN TEMP IS EXPECTED FOR WEDNESDAY WITH HIGH
CONFIDENCE FOR DRY CONDITIONS TO CONTINUE ACROSS THE ENTIRE
REGION SOUTH OF STATE ROUTE 6 IN NORTHERN PENN. SIMILAR TO
TUESDAY...A FEW LIGHT SHOWERS COULD BRUSH LOCATIONS RIGHT ALONG
THE PENN/NY BORDER.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
RISING HEIGHTS ALOFT AND A MILD SW TO WEST FLOW WILL MAINTAIN MILD
CONDITIONS THROUGH THURSDAY. THE MAIN FCST CHALLENGES LATE THIS
WEEK AND OVER THE WEEKEND INVOLVES 1) THE SPEED/TRACK OF LOW
PRESSURE AND TIMING OF RAIN SHOWERS ALONG TRAILING COLD FRONT ON
THURS- THURS NGT AND 3) PCPN CHANCES FOR THE SECOND HALF OF EASTER
WEEKEND.
A MORE PROGRESSIVE GFS/GEFS IS A MAIN THEME THROUGH THE ENTIRE
PERIOD. THE NAM/EC/CMC ALL SHOW VARYING DEGREE OF SPREAD (SLOWER
AND FURTHER TO THE SOUTH) VS. THE GFS IN REGARDS TO THE LEAD LOW
TRACKING ENEWD FROM THE MIDWEST. A COMPROMISE/CONSENSUS SOLUTION
WAS USED IN AN ATTEMPT TO MITIGATE THE DIFFERENCES WHICH STILL
POINTS TO THE HIGHEST POPS LATER THURSDAY INTO THURSDAY
NIGHT. THERE IS MODERATE CONFIDENCE FOR RAINFL BETWEEN ONE-QUARTER
AND ONE-HALF INCH OCCURRING VIA NUMEROUS SHOWERS ALONG AND AHEAD
OF A COLD FRONT.
A VERY BRIEF SHOT OF COOLER TEMPS IS IN STORE FOR FRIDAY AND
FRIDAY NIGHT...AS 850 MB TEMPS DIP TO BETWEEN -4C AND -9C OVER
THE STATE AT 06Z SAT. SFC HIGH PRESSURE SLIDES TO THE NEW ENGLAND
COAST ON SATURDAY...BRINGING A DEVELOPING SOUTH TO SE LLVL FLOW
ACROSS THE REGION WITH REBOUNDING TEMPS.
12Z/00Z EC/ECENS STILL FAVORS A DRY AND SEASONABLE EASTER WEEKEND
WITH A SW/NE RIDGE OF SFC HIGH PRESSURE HANGING TOUGH FROM THE
MID ATLANTIC SEABOARD TO NOVA SCOTIA.
THE PERSISTENTLY FAST GFS WOULD RETURN MOISTURE AND RAIN TO THE
AREA ON SUNDAY OR 24+ HOURS AHEAD OF THE ECMWF. THEREFORE TRIED TO
SPLIT THE DIFFERENCE AGAIN AND HEDGED HIGHER POPS TOWARD SLOWER
SOLN SUNDAY NIGHT INTO MONDAY WITH LOW CONFIDENCE.
MIDWEEK TEMPERATURES TO THE SOUTH/EAST OF THE FRONTAL BOUNDARY
SHOULD BE RATHER MILD/ABOVE NORMAL WITH A BUST SCENARIO LKLY TO
THE UPSIDE. NATIONAL/REGIONAL SUPERBLEND TEMPERS MAX/MIN TEMPS
FRI-MON BUT STILL NEAR OR SLIGHTLY ABOVE LATE MARCH CLIMO.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
SURFACE HIGH PRESSURE AND BROAD UPPER RIDGE WILL KEEP WIDESPREAD
VFR CONDITIONS IN PLACE OVER CENTRAL PA TODAY. AS SW FLOW
INCREASES TODAY...LIGHT WINDS WILL AGAIN BECOME A BIT BREEZY AS
SURFACE FLOW INCREASES TO AROUND 10 MPH WITH GUSTS TO 10-20 MPH
ACOESS MAINLY WESTERN HALF. MID/HIGH CLOUDS WILL INCREASE THROUGH
THE DAY.
FAST FLOW CONTINUES TONIGHT...WITH LLWS LIKELY AS 850MB FLOW
REMAINS BETWEEN 40-50KTS. SURFACE WINDS SHOULD ALSO HOLD AROUND
5-10 MPH OVERNIGHT...ESP NW HALF AND LAUREL HIGHLANDS. THERE WILL
BE JUST A SLIGHT CHANCE FOR A SHOWER ALONG THE NY BORDER AS A WARM
FRONT EXTENDS EASTWARD FROM THE GLAKES...BUT VFR CONDITIONS WILL
HOLD THROUGH TONIGHT.
CIG RESTRICTIONS BEGIN TO WORK INTO NW MTNS WED NIGHT INTO THU
ALONG THE FRONTAL BOUNDARY AHEAD OF AN APPROACHING LATE WEEK
STORM. SHOWERS LIKELY HOLD OFF UNTIL THE DAY THU...WITH A LITTLE
THUNDER POSS.
OUTLOOK...
WED...MVFR AND SCT -SHRA POSS NW. OTHERWISE PRIMARILY VFR.
WED NIGHT-THU NIGHT...SHRA AND RESTRICTIONS LIKELY NW
HALF...MAINLY VFR SE. SOME THUNDER POSS THU. LLWS POSS THU NIGHT.
FRI...RESTRICTIONS POSS EARLY. THEN IMPROVING CONDITIONS.
SAT...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/STEINBUGL
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
533 AM EDT TUE MAR 22 2016
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE OVER CENTRAL PENNSYLVANIA WILL SLIDE
EAST TO THE MID ATLANTIC COAST BY THIS AFTERNOON.
A WARM FRONT LIFTING SLOWLY NORTH ACROSS THE GREAT LAKES WILL
BRING INCREASING MID AND HIGH LEVEL CLOUDS OVER MOST AREAS OF THE
STATE TODAY...WITH THE CHANCE OF A FEW SHOWERS LIMITED TO FAR
NORTHERN PENNSYLVANIA LATE TODAY AND TONIGHT.
A POTENT AREA OF LOW PRESSURE AND SOUTHWARD TRAILING COLD FRONT
WILL APPROACH FROM THE MISSISSIPPI VALLEY LATE IN THE WEEK...LIKELY
PASSING THROUGH PA LATE THURSDAY INTO FRIDAY...AND BRINGING
PERIODS OF SHOWERS ALONG WITH A CHANCE OF A FEW THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RIDGE OF HIGH PRESSURE OVER THE COMMONWEALTH EARLY TODAY WILL
BRING TRANQUIL BUT CHILLY EARLY SPRING CONDITIONS...WITH SUNRISE
MIN TEMPS RANGING FROM THE UPPER TEENS TO LOWER 20S NORTH...TO
THE MID AND UPPER 20S IN MOST OTHER LOCATIONS.
MID AND HIGH CLOUD SHIELD STREAMING EAST FROM THE WESTERN LAKES
AND OHIO VALLEY REGION WILL SPREAD OVER THE WESTERN HALF OF THE
CWA BY DAYBREAK...BUT MOST OF THE CLOUD COVER THROUGH 12Z WILL
CONSIST OF A VEIL OF THIN CIRRUS...ABOVE SOME SCT ALTO CU.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
HEIGHTS ALOFT WILL CONTINUE TO RISE THROUGH TODAY...BUT OVERALL
THE FLOW ALOFT WILL BECOME QUASI-ZONAL ALLOWING MOISTURE /MAINLY
IN THE FORM OF VARYING AMOUNTS OF ALTO CU AND CIRRUS/ TO SPILL
ESE OVER INTO THE REGION FROM THE GR LAKES AND MIDWEST.
ON THE SURFACE...A DEVELOPING WARM FRONTAL BOUNDARY WILL SNAKE ITS
WAY FROM THE WESTERN GLAKES REGION...EAST TO NEAR THE I-90
CORRIDOR IN CENTRAL NEW YORK.
THE PRIMARY WEST TO SWRLY LOW-MID LEVEL ISENTROPIC LIFT OVER THIS
WARM FRONT WILL BE WELL NORTH OF THE REGION...WHICH WILL CONFINE
THE SOUTHERN EDGE OF ANY LIGHT SHOWERS TO I-86 OR POINTS NORTH IN
SOUTHERN AND WESTERN NEW YORK STATE.
HOWEVER...07Z HRRR IS BONE DRY THROUGH LATE TODAY...AND THE 00Z
NAM AND 03Z SREF CONTINUE THE ABSENCE OF ANY QPF THROUGH AT LEAST
WEDNESDAY MORNING.
IT WILL BE MILDER THAN MONDAY...BY 12-15 DEG F ON AVERAGE...AS
THE HIGH SLIPS OFF THE COAST AND OUR LOW LEVEL FLOW BACKS FROM
WEST TO SOUTHWEST AT 5-10 KTS. EXPECT MID TO LATE AFTERNOON TEMPS
TO RANGE FROM THE L-M 50S ACROSS THE NRN MTNS WHERE THICKER CLOUD
COVER WILL BE PRESENT...TO THE LOWER 60S THROUGHOUT THE SOUTHERN
TIER VALLEYS. VERTICAL MIXING UP TO AROUND 5 KFT AGL THIS
AFTERNOON WILL BRING GUST POTENTIAL IN THE TEENS TO LOWER 20 KT
RANGE.
MILDER TEMPS FOR TONIGHT UNDER VARIABLE AMOUNTS OF MID CLOUDS.
LOWS WILL A FEW TO SVRL DEG F ABOVE NORMAL...OR IN THE UPPER 30S
TO LOWER 40S.
A FEW DEG F INCREASE IN TEMP IS EXPECTED FOR WEDNESDAY WITH HIGH
CONFIDENCE FOR DRY CONDITIONS TO CONTINUE ACROSS THE ENTIRE
REGION SOUTH OF STATE ROUTE 6 IN NORTHERN PENN. SIMILAR TO
TUESDAY...A FEW LIGHT SHOWERS COULD BRUSH LOCATIONS RIGHT ALONG
THE PENN/NY BORDER.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
RISING HEIGHTS ALOFT AND A MILD SW TO WEST FLOW WILL MAINTAIN MILD
CONDITIONS THROUGH THURSDAY. THE MAIN FCST CHALLENGES LATE THIS
WEEK AND OVER THE WEEKEND INVOLVES 1) THE SPEED/TRACK OF LOW
PRESSURE AND TIMING OF RAIN SHOWERS ALONG TRAILING COLD FRONT ON
THURS- THURS NGT AND 3) PCPN CHANCES FOR THE SECOND HALF OF EASTER
WEEKEND.
A MORE PROGRESSIVE GFS/GEFS IS A MAIN THEME THROUGH THE ENTIRE
PERIOD. THE NAM/EC/CMC ALL SHOW VARYING DEGREE OF SPREAD (SLOWER
AND FURTHER TO THE SOUTH) VS. THE GFS IN REGARDS TO THE LEAD LOW
TRACKING ENEWD FROM THE MIDWEST. A COMPROMISE/CONSENSUS SOLUTION
WAS USED IN AN ATTEMPT TO MITIGATE THE DIFFERENCES WHICH STILL
POINTS TO THE HIGHEST POPS LATER THURSDAY INTO THURSDAY
NIGHT. THERE IS MODERATE CONFIDENCE FOR RAINFL BETWEEN ONE-QUARTER
AND ONE-HALF INCH OCCURRING VIA NUMEROUS SHOWERS ALONG AND AHEAD
OF A COLD FRONT.
A VERY BRIEF SHOT OF COOLER TEMPS IS IN STORE FOR FRIDAY AND
FRIDAY NIGHT...AS 850 MB TEMPS DIP TO BETWEEN -4C AND -9C OVER
THE STATE AT 06Z SAT. SFC HIGH PRESSURE SLIDES TO THE NEW ENGLAND
COAST ON SATURDAY...BRINGING A DEVELOPING SOUTH TO SE LLVL FLOW
ACROSS THE REGION WITH REBOUNDING TEMPS.
12Z/00Z EC/ECENS STILL FAVORS A DRY AND SEASONABLE EASTER WEEKEND
WITH A SW/NE RIDGE OF SFC HIGH PRESSURE HANGING TOUGH FROM THE
MID ATLANTIC SEABOARD TO NOVA SCOTIA.
THE PERSISTENTLY FAST GFS WOULD RETURN MOISTURE AND RAIN TO THE
AREA ON SUNDAY OR 24+ HOURS AHEAD OF THE ECMWF. THEREFORE TRIED TO
SPLIT THE DIFFERENCE AGAIN AND HEDGED HIGHER POPS TOWARD SLOWER
SOLN SUNDAY NIGHT INTO MONDAY WITH LOW CONFIDENCE.
MIDWEEK TEMPERATURES TO THE SOUTH/EAST OF THE FRONTAL BOUNDARY
SHOULD BE RATHER MILD/ABOVE NORMAL WITH A BUST SCENARIO LKLY TO
THE UPSIDE. NATIONAL/REGIONAL SUPERBLEND TEMPERS MAX/MIN TEMPS
FRI-MON BUT STILL NEAR OR SLIGHTLY ABOVE LATE MARCH CLIMO.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
ANY SHOWERS HAVE DISSIPATED AND THE SKIES ARE CLEARING ACROSS THE
REGION. THIS WILL ALLOW FOR A DROP IN TEMPERATURES...HOWEVER THE
DEWPOINTS REMAIN IN THE TEENS...AND THOUGH WINDS SHOULD DECOUPLE
OVERNIGHT...IT SHOULD BE TO DRY FOR RESTRICTIONS DUE TO FOG/MIST.
VFR SHOULD DOMINATE TODAY WITH BREEZY CONDITIONS DUE TO STRONG
SOUTHWESTERLY FLOW ALOFT.
SCATTERED SHOWERS REMAIN POSSIBLE TOMORROW NIGHT DUE TO MOIST
UPSLOPE FLOW FROM A PASSING TROUGH IN THE NW MOUNTAINS 23 TO 03Z
TOMORROW NIGHT...MAINLY AT BFD.
OUTLOOK...
TUE...VFR. BREEZY.
WED...PRIMARILY VFR...WITH MVFR AND SCT -SHRA POSS NW.
WED NIGHT - THU NIGHT...MAINLY VFR SE...BUT SHRA AND RESTRICTIONS
LIKELY NW HALF. LLWS POSS THU NIGHT.
FRI...RESTRICTIONS POSS EARLY. THEN IMPROVING CONDITIONS.
SAT...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/STEINBUGL
AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
240 AM EDT TUE MAR 22 2016
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE OVER CENTRAL PENNSYLVANIA WILL SLIDE
EAST TO THE MID ATLANTIC COAST BY THIS AFTERNOON.
A WARM FRONT LIFTING SLOWLY NORTH ACROSS THE GREAT LAKES WILL
BRING INCREASING MID AND HIGH LEVEL CLOUDS OVER MOST AREAS OF THE
STATE TODAY...WITH THE CHANCE OF A FEW SHOWERS LIMITED TO FAR
NORTHERN PENNSYLVANIA LATE TODAY AND TONIGHT.
A POTENT AREA OF LOW PRESSURE AND SOUTHWARD TRAILING COLD FRONT
WILL APPROACH FROM THE MISSISSIPPI VALLEY LATE IN THE WEEK...LIKELY
PASSING THROUGH PA LATE THURSDAY INTO FRIDAY...AND BRINGING
PERIODS OF SHOWERS ALONG WITH A CHANCE OF A FEW THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
RIDGE OF HIGH PRESSURE OVER THE COMMONWEALTH EARLY TODAY WILL
BRING TRANQUIL BUT CHILLY EARLY SPRING CONDITIONS...WITH MIN
TEMPS IN THE TEENS NORTH...TO LOWER AND MID 20S IN MOST OTHER
AREAS.
MID AND HIGH CLOUD SHIELD STREAMING EAST FROM THE WESTERN LAKES
AND OHIO VALLEY REGION WILL SPREAD OVER THE WESTERN HAF OF THE CWA
BY DAYBREAK...BUT MOST OF THE CLOUD COVER THROUGH 12Z WILL
CONSIST OF A VEIL OF THIN CIRRUS...ABOVE SOME SCT ALTO CU.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
HEIGHTS ALOFT WILL CONTINUE TO RISE THROUGH TODAY...BUT OVERALL
THE FLOW ALOFT WILL BECOME QUASI-ZONAL ALLOWING MOISTURE TO SPILL
OVER INTO THE REGION FROM THE GR LAKES AND MIDWEST.
ON THE SURFACE...A WARM FRONT WILL BEGIN SNAKING INTO THE LOWER
LAKES FROM THE MIDWEST WHICH COULD BRING SOME SHOWERS TO FAR
NORTHERN PA TWD DUSK. HOWEVER...THE 00Z NAM AND 05Z HRRR ARE BONE
DRY THROUGH 00Z WED.
IT WILL BE MILDER THAN MONDAY BY 10-15 DEG ON AVERAGE AS THE HIGH
SLIPS OFF THE COAST AND OUR LOW LEVEL FLOW BACKS FROM WEST TO
SOUTHWEST AT 5-10 KTS. VERTICAL MIXING UP TO AROUND 5 KFT AGL THIS
AFTERNOON WILL BRING GUST POTENTIAL IN THE TEENS TO LOWER 20 KT
RANGE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
RISING HEIGHTS ALOFT AND A MILD SW TO WEST FLOW WILL CONTINUE TO
SUPPORT A WARMING TREND THROUGH MIDWEEK. THE MAIN FCST CHALLENGES
INVOLVE 1) PLACEMENT PCPN AXIS ASSOCIATED WITH QUASI-STATIONARY
FRONTAL BOUNDARY NEAR PA/NY BORDER TUE NGT-WED; 2) SPEED/TRACK OF
LOW PRESSURE AND TIMING OF RAIN SHOWERS ALONG TRAILING COLD FRONT
ON THURS-THURS NGT AND 3) PCPN CHANCES FOR THE SECOND HALF OF
EASTER WEEKEND.
A MORE PROGRESSIVE GFS/GEFS IS A MAIN THEME THROUGH THE ENTIRE
PERIOD. THE NAM/EC/CMC ALL SHOW VARYING DEGREE OF SPREAD (SLOWER
AND FURTHER TO THE SOUTH) VS. THE GFS IN REGARDS TO THE LEAD LOW
TRACKING ENEWD FROM THE MIDWEST. A COMPROMISE/CONSENSUS SOLUTION
WAS USED IN AN ATTEMPT TO MITIGATE THE DIFFERENCES WHICH STILL
POINTS TO THE HIGHEST POPS LATER THURSDAY INTO THURSDAY NIGHT.
EC/ECENS STILL FAVORS A DRY AND SEASONABLE EASTER WEEKEND WITH
HIGH PRES MIGRATING OVER THE NORTHEAST STATES AND OFF THE ECOAST
BY SUNDAY NIGHT. THE PERSISTENTLY FAST GFS WOULD RETURN MOISTURE
AND RAIN TO THE AREA ON SUNDAY OR 24+ HOURS AHEAD OF THE ECMWF.
THEREFORE TRIED TO SPLIT THE DIFFERENCE AGAIN AND HEDGED HIGHER
POPS TOWARD SLOWER SOLN SUNDAY NIGHT INTO MONDAY WITH LOW CONFIDENCE.
MIDWEEK TEMPERATURES TO THE SOUTH/EAST OF THE FRONTAL BOUNDARY
SHOULD BE RATHER MILD/ABOVE NORMAL WITH A BUST SCENARIO LKLY TO
THE UPSIDE. NATIONAL/REGIONAL SUPERBLEND TEMPERS MAX/MIN TEMPS
FRI-MON BUT STILL NEAR OR SLIGHTLY ABOVE LATE MARCH CLIMO.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
ANY SHOWERS HAVE DISSIPATED AND THE SKIES ARE CLEARING ACROSS THE
REGION. THIS WILL ALLOW FOR A DROP IN TEMPERATURES...HOWEVER THE
DEWPOINTS REMAIN IN THE TEENS...AND THOUGH WINDS SHOULD DECOUPLE
OVERNIGHT...IT SHOULD BE TO DRY FOR RESTRICTIONS DUE TO FOG/MIST.
VFR SHOULD DOMINATE TODAY WITH BREEZY CONDITIONS DUE TO STRONG
SOUTHWESTERLY FLOW ALOFT.
SCATTERED SHOWERS REMAIN POSSIBLE TOMORROW NIGHT DUE TO MOIST
UPSLOPE FLOW FROM A PASSING TROUGH IN THE NW MOUNTAINS 23 TO 03Z
TOMORROW NIGHT...MAINLY AT BFD.
OUTLOOK...
TUE...VFR. BREEZY.
WED...PRIMARILY VFR...WITH MVFR AND SCT -SHRA POSS NW.
WED NIGHT - THU NIGHT...MAINLY VFR SE...BUT SHRA AND RESTRICTIONS
LIKELY NW HALF. LLWS POSS THU NIGHT.
FRI...RESTRICTIONS POSS EARLY. THEN IMPROVING CONDITIONS.
SAT...VFR.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...STEINBUGL
AVIATION...LA CORTE/CERU
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1024 AM EDT TUE MAR 22 2016
.SYNOPSIS...
DRY HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE AREA TODAY. A
COLD FRONT AND ASSOCIATED MOISTURE WILL CROSS THE REGION LATE
THURSDAY...WITH ANOTHER MOIST AREA OF LOW PRESSURE RETURNING LATER
IN THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
1015 AM UPDATE...TEMPS STILL APPEAR TO BE RISING SLIGHTLY FASTER
THAN THE PREVIOUS FORECAST VALUES. RAP IS THE SHORT TERM MODEL
THAT HAS BEST CAUGHT ONTO THIS TREND...SO I BLENDED IN A PORTION
OF THIS THRU THE DAY. MAX TEMPS ARE A DEGREE OR TWO HIGHER
PARTICULARLY IN THE PIEDMONT. HOWEVER...ON THE OTHER HAND IT
APPEARS TO BE ACCOUNTING FOR TOO MUCH MIXING...DROPPING OUT DEWPTS
APPRECIABLY MORE THAN THE OTHER MODELS. I STILL THINK THE UPDATE
MADE EARLIER THIS MORNING...WHICH SUGGESTS MODEST DEWPT DECLINES
DUE TO MIXING...LOOKS GOOD IN LIGHT OF INCREASING MOIST SW FLOW. RH
NOW BOTTOMS OUT NEAR 20 PERCENT OVER MOST OF THE AREA. WE SHOULD
FIND OUT SOON FROM NC/SC FIRE AGENCIES REGARDING NEED FOR A FIRE
DANGER STATEMENT.
AS OF 300 AM...AN UPPER RIDGE WILL BEGIN TO BUILD ACROSS THE EASTERN
STATES TODAY...AS SFC HIGH PRESSURE CENTER SHIFTS EAST OFF THE FL
COAST. SWLY RETURN FLOW WILL INCREASE ATOP THE CWFA...RESULTING
IN A NICE REBOUND IN TEMPS AFTER A CHILLY START TO THE DAY. UNDER
SUNNY SKIES...EXPECT HIGHS IN THE 50S TO MID 60S IN THE MTNS AND
MID 60S TO AROUND 70 ACROSS THE PIEDMONT...WHICH IS CLOSE TO LATE
MARCH NORMALS. THE WARMER TEMPS COMBINED WITH STILL LOW DEWPTS
WILL RESULT IN POTENTIALLY CRITICAL RH FOR FIRE WEATHER CONCERNS
(SEE FIRE WEATHER SECTION BELOW).
TONIGHT...THE COMBINATION OF INCREASING LLVL THICKNESSES AND
LIGHT SWLY SFC WINDS SHOULD LIMIT RADIATIONAL COOLING...AND HENCE
FROST/FREEZE CONCERNS ARE NOT EXPECTED. LOWS UNDER CLEAR SKIES
WILL BE A CATEGORY OR TWO ABOVE NORMAL (UPR 30S TO MID 40S).
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM EDT...A CLOSED 500 MB LOW PRESSURE SYSTEM WILL EMERGE
ACROSS THE SOUTHERN PLAINS ON WEDNESDAY...WITH STRENGTHENING
SOUTHWESTERLY FLOW EXPECTED ACROSS THE SOUTHEAST STATES. PROFILES
REMAIN DRY AND TEMPERATURES WILL WARM TO NEARLY 10 DEGREES ABOVE
CLIMATOLOGY.
ALTHOUGH THIS SYSTEM WILL LIFT AND PHASE TOWARD THE GREAT LAKES
WEDNESDAY NIGHT THROUGH THURSDAY...IT WILL SEND SEVERAL FORCING
MECHANISMS EASTWARD INTO OUR FORECAST AREA. UPPER LEVEL DIVERGENCE
WILL ARRIVE TOWARD THURSDAY EVENING AS A 120 KT UPPER JETLET SLIDES
EAST ACROSS THE APPALACHIANS AHEAD OF THE TROUGH AXIS. DEEP LAYER Q
VECTOR CONVERGENCE WILL ALSO CROSS THE REGION THURSDAY EVENING.
FINALLY...THERE SHOULD BE A FAIRLY NARROW BUT DECENTLY STRONG LINE
OF LOW LEVEL CONVERGENCE ALONG THE PASSING COLD FRONT. THE LATE
DAY/EVENING TIMING COULD BE FAVORABLE FOR BETTER INSTABILITY IF
DEWPOINTS SUFFICIENTLY REBOUND THROUGH THURSDAY...BUT INSTABILITY
WILL LIKELY BE HIGHER TO THE WEST THURSDAY AFTERNOON. THE LOW LEVEL
JET SHOULD APPROACH 40 KT IN THE BEST PRE/FRONTAL WARM ADVECTION THU
AFTERNOON...BUT NEAR SURFACE WINDS WILL PROBABLY NOT BE VERY BACKED.
THIS SETUP WILL HAVE TO BE MONITORED FOR THE POTENTIAL FOR A NARROW
LINE OF ISOLATED SEVERE STORMS TO DEVELOP...ESPECIALLY GIVEN THE LOW
LEVEL BULK SHEAR AND LAPSE RATES GENERATING QLCS FAVORING SHERB
VALUES ABOVE 1 BY 00Z FRI.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 300 AM EDT TUESDAY...ZONAL FLOW WILL DEVELOP BEHIND THE
DEPARTING TROUGH ON FRIDAY...WITH POST FRONTAL PROFILES DRYING OUT.
UNCERTAINTY OVER THE UPPER LEVEL FLOW PATTERN WILL THEN STEADILY
INCREASE FROM SATURDAY ONWARD. THE OPERATIONAL GFS REMAINS MUCH
FASTER WITH A SYSTEM MOVING EAST OF THE ROCKIES ACROSS THE PLAINS
LATE IN THE WEEKEND...WHILE THE ECMWF KEEPS A MUCH SLOWER CLOSED
SYSTEM WELL TO THE WEST. THE GEFS MEAN REMAINS SOMEWHERE IN BETWEEN
THESE SOLUTIONS. A CONSENSUS BLEND WILL MEAN A MAINLY DRY SATURDAY
WITH TEMPS A TOUCH BELOW CLIMO IN THE MOUNTAINS AND A TOUCH ABOVE IN
THE FOOTHILLS/PIEDMONT.
WITH HIGH UNCERTAINTY...WE WILL FEATURE A WEAK UPGLIDE PATTERN
DEVELOPING LATE IN THE WEEKEND. WITH THE NOSE OF LINGERING SURFACE
HIGH PRESSURE STILL IN PLACE ALONG THE EASTERN SEABOARD...WEAK IN
SITU OR HYBRID COLD AIR DAMMING MAY DEVELOP SUNDAY AFTERNOON. WILL
JUST SHADE TEMPS TOWARD THE COOLER SIDE OF MOS AT THIS POINT AND
ALLOW POP FOR RAIN/SHOWERS TO SLOWLY EXPAND. IT IS ENTIRELY UNCLEAR
WHETHER MONDAY WILL BE POST FRONTAL LIKE THE GFS OR PRE FRONTAL LIKE
THE ECMWF...OR EXHIBIT A DAYTIME FROPA LIKE THE ENSEMBLE MEANS. WILL
THUS KEEP LOW END SHOWER CHANCES GOING IN LINE WITH NCEP GUIDANCE
THROUGH MONDAY.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
AT KCLT AND ELSEWHERE...NO SIGNIFICANT CHANGES FOR THE 12Z TAFS.
VFR...WITH GENERALLY SKC AND UNRESTRICTED VSBY THRU THE PERIOD...AS
DRY HIGH PRESSURE TRACKS EAST ALONG THE GULF COAST. THE HIGH WILL
SHIFT OVER THE WESTERN ATLANTIC TODAY...ALLOWING WINDS TO INCREASE
OUT OF THE SW. A FEW LOW-END GUSTS EXPECTED ACROSS THE AREA DURING
PEAK MIXING IN THE AFTN...THEN WINDS DIMINISH SOMEWHAT AROUND SUNSET.
OUTLOOK...DRY HIGH PRESSURE WILL LINGER ACROSS THE SOUTHEAST
STATES THRU WEDNESDAY. THEN A COLD FRONT WILL APPROACH FROM
THE WEST THURSDAY...AND CROSS THE REGION THURSDAY NIGHT INTO
FRIDAY...BRINGING A ROUND OF SHRA AND POSSIBLY TSRA.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:
WWW.WEATHER.GOV/GSP/AVIATION
&&
.FIRE WEATHER...
HIGH PRESSURE WILL SHIFT EAST OF THE AREA...SETTING UP INCREASING
SOUTHWESTERLY RETURN FLOW ATOP THE REGION TODAY. TEMPS ARE EXPECTED
TO REBOUND INTO THE UPPER 60S FOR MOST OF THE AREA...WHILE DWPTS MIX
INTO THE MID TO UPR 20S. THIS WILL RESULT IN RH VALUES FALLING TO
NEAR 20 PCT FOR MOST OF THE AREA THIS AFTN. THE LATEST FCST HAS AT
LEAST 4 HOURS OF CRITICAL RH IN THE NE GA PIEDMONT COUNTIES...AND
CLOSE TO THAT IN RABUN/HABERSHAM. THE 10 HR FUELS HAVE DROPPED
TO 8 PCT OR LOWER YESTERDAY...AND SO WE WILL ISSUE AN SPS FIRE
DANGER STATEMENT FOR NE GA TODAY. AS FOR THE CAROLINAS...THE
RH LOOKS CRITICAL...BUT WINDS SHOULD REMAIN WELL BELOW RED
FLAG. HOWEVER...WE WILL STILL COORDINATE WITH LAND MANAGERS ON
FUEL MOISTURES/CONDITIONS FOR ANY NEEDED PRODUCTS.
ALTHOUGH SOUTHWEST FLOW WILL CONTINUE THROUGH WED AND PERMIT
DEWPOINTS TO FURTHER REBOUND...MAXIMUM TEMPERATURES CLIMBING
WELL INTO THE 70S IN MANY AREAS WILL ONCE AGAIN ALLOW CRITICAL
RH VALUES AROUND 25 PERCENT TO DEVELOP. SOUTHWEST WINDS OF 10 TO
15 MPH COULD GENERATE A FEW LOW END GUSTS AS WELL. ANOTHER FIRE
DANGER STATEMENT COULD BE NEEDED FOR NE GA OR BEYOND FOR WEDNESDAY.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FIRE DANGER STATEMENT UNTIL 7 PM EDT THIS EVENING FOR GAZ010-
017-018-026-028-029.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/WIMBERLEY
SHORT TERM...HG
LONG TERM...HG
AVIATION...ARK
FIRE WEATHER...ARK
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
943 PM CDT WED MAR 23 2016
.UPDATE...
WINDS HAD WEAKENED SOME OVER THE MIDSOUTH FOLLOWING SUNSET... BUT
REMAINED OCCASIONALLY GUSTY ALONG AND WEST OF THE MS RIVER.
CONSIDERED EARLIER DROPPING THE WIND ADVISORY...BUT NAM AND GFS
LAMP GUIDANCE INDICATE A POTENTIAL RETURN TO ADVISORY LEVEL WINDS
AFTER 4 AM...WITH THE APPROACH OF A SURFACE PRESSURE TROF. AN
EARLIER FORECAST UPDATE INCLUDED THUNDERSTORM TIMING ADJUSTMENTS.
00Z NAM AND 01Z HRRR MODEL RUNS WERE IN GOOD AGREEMENT IN
DEVELOPING PREFRONTAL ELEVATED SHOWERS DURING THE OVERNIGHT. BEST
THUNDER POTENTIAL WILL LIKELY ARRIVE OVER EAST AR / NORTHWEST MS
BY 6 AM. THE NAM SHOWED A SHARPLY DEFINED SHORTWAVE TROF ROTATING
THROUGH SOUTHERN MO...AROUND THE BASE OF THE UPPER LOW SHORTLY
AFTER SUNRISE. THIS FEATURE WILL SERVE TO SHARPEN CONVECTIVE FOCUS
OVER WEST TN DURING THE DAYLIGHT MORNING HOURS. TO THE SOUTH... A
SUBTLER SHORTWAVE IS DEPICTED EJECTING FROM THE ARKLATEX INTO THE
NORTH MS BY MIDDAY THURSDAY. THIS LATER FEATURE WILL LIKELY
ENCOUNTER GREATER INSTABILITY OVER NORTHEAST MS...UP TO 1500 J/KG
BY MIDMORNING.
NO ADDITIONAL INFORMATION ON THE STATUS OF THE COLUMBUS AFB
RADAR...KGWX.
CURRENT FORECAST ON TRACK...WITH NO ADDITIONAL CHANGES AT THIS
TIME.
PWB
&&
.PREV DISCUSSION... /ISSUED 634 PM CDT WED MAR 23 2016/
UPDATE...
UPDATED FOR THE 00Z AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 306 PM CDT WED MAR 23 2016/
DISCUSSION...
AN UPPER LEVEL LOW PRESSURE SYSTEM OVER WESTERN KANSAS THIS
AFTERNOON WILL LIFT OUT TO THE NORTHEAST THROUGH THURSDAY. AS IT
DOES SO...A SHORTWAVE WILL ROTATE THROUGH THE BASE OF THE TROUGH
AND ROTATE ACROSS THE MID SOUTH THURSDAY. STRONG AND GUSTY
SOUTHERLY WINDS SHOULD CONTINUE OVERNIGHT AHEAD OF THIS
SYSTEM...THEREFORE WILL LEAVE THE WIND ADVISORY IN PLACE EVEN
THOUGH IT REMAINS BORDERLINE. SHOWERS AND THUNDERSTORMS SHOULD
DEVELOP ACROSS THE ARKLATEX LATER THIS EVENING AND MOVE INTO
WESTERN SECTIONS OF THE MID SOUTH AFTER MIDNIGHT. INSTABILITY
SHOULD WANE TONIGHT ACROSS OUR AREA SO ANY SEVERE STORMS OVER THE
ARKLATEX SHOULD WEAKEN PRIOR TO REACHING OUR CWA.
AS THE SHORTWAVE ROTATES ACROSS THE REGION...MID LEVEL LAPSE RATES
SHOULD STEEPEN TO BETWEEN 6.5 AND 7.0 C/KM OVER TOP OF A PLUME OF
SURFACE DEWPOINTS RISING INTO THE LOWER 60S ACROSS NORTHEAST
MISSISSIPPI BY EARLY THURSDAY AFTERNOON. AS SURFACE HEATING
COMMENCES THIS SHOULD GENERATE MODEST INSTABILITY WITH CAPE
RANGING FROM 500-1000 J/KG OVER THESE LOCATIONS. THERE REMAINS
MODEL DISAGREEMENT BETWEEN THE LATEST 12Z RUNS...WITH THE NAM AND
TO A LESSER DEGREE THE GFS ON THE HIGHER END OF INSTABILITY WITH
THE ECMWF KEEPING CAPES LESS THAN 500 J/KG. A SLIGHT RISK FOR
SEVERE WEATHER ON THURSDAY STRETCHES ACROSS NORTHEAST MISSISSIPPI
INTO WEST TENNESSEE. THE MOST LIKELY LOCATIONS TO EXPERIENCE
SEVERE STORMS TOMORROW SHOULD BE ACROSS NORTHEAST MISSISSIPPI
WHERE INSTABILITY IS GREATEST. ALL OF THE MODEL GUIDANCE SUGGESTS
STRONG WIND SHEAR THROUGH THE ATMOSPHERE WITH A TENDENCY FOR LOW
LEVEL VEERING OF THE WINDS THROUGH THE DAY. THIS SHEAR IS MORE
THAN SUFFICIENT TO SUPPORT ORGANIZED SEVERE STORMS WHERE IT ALIGNS
WITH THE BEST INSTABILITY. THE PRIMARY THREATS AT THIS TIME APPEAR
TO BE DAMAGING WINDS AND ISOLATED TORNADOES. SHOWERS AND
THUNDERSTORMS SHOULD SHIFT EAST OF THE MID SOUTH BY THURSDAY
EVENING.
HIGH PRESSURE WILL BUILD BACK INTO THE REGION FRIDAY WITH A RETURN
TO DRY WEATHER AND COOLER TEMPERATURES. THIS HIGH PRESSURE WILL
SHIFT EAST BY THE WEEKEND WITH WARMER TEMPERATURES EXPECTED.
ANOTHER SHORTWAVE WILL MOVE ACROSS THE REGION SUNDAY AND SUNDAY
NIGHT WITH ADDITIONAL STORM CHANCES. ANOTHER BRIEF COOL DOWN IS
ANTICIPATED MONDAY BEFORE WARMING BACK TO NEAR OR SLIGHTLY ABOVE
AVERAGE TEMPERATURES THROUGH THE MIDDLE OF NEXT WEEK.
JLH
&&
.AVIATION...
00Z TAF CYCLE
VFR CONDITIONS WILL CONTINUE THROUGH THE EVENING HOURS. CEILINGS
WILL DROP TO MVFR LEVELS OVERNIGHT AND REMAIN THERE THROUGH
THURSDAY MORNING WITH A RETURN TO VFR CONDITIONS BY AFTERNOON.
SHOWERS AND THUNDERSTORMS WILL MOVE INTO WESTERN SECTIONS OF THE
FORECAST AREA OVERNIGHT AND WILL PUSH EAST WITH ACTIVITY EXITING
THE EASTERN PART OF THE FORECAST AREA IN THE AFTERNOON. WINDS WILL
BE MAINLY FROM THE SOUTH AT 15 TO 20 KNOTS WITH OCCASIONAL HIGHER
GUSTS. WINDS WILL BECOME MORE WESTERLY BY THURSDAY AFTERNOON.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR COAHOMA-DESOTO-PANOLA-
QUITMAN-TALLAHATCHIE-TATE-TUNICA.
TN...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR DYER-LAKE-LAUDERDALE-
OBION-SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
901 PM CDT WED MAR 23 2016
.UPDATE...
AT 700 PM...DEEP LOW PRESSURE WAS LOCATED OVER NE KANSAS. A
PRE FRONTAL TROUGH EXTENDED FROM THE LOW INTO NORTH CENTRAL TEXAS
AND A COLD FRONT TRAILED TO THE WEST EXTENDING FROM THE SFC LOW
ACROSS THE TEXAS PANHANDLE. 00Z SOUNDINGS FROM CRP AND LCH
CONTINUE TO SHOW A STOUT CAP IN PLACE NEAR 850 MB. 850 MB DEW
POINTS ARE AROUND 10 C BUT MOISTURE LEVELS DRY OUT QUICKLY AT 700
MB. AT 300 MB...A DEEP UPPER LOW WAS SPINNING OVER THE
KANSAS/NEBRASKA WITH A 90-100 KT JET TO THE E-SE OF THE LOW. WEAK
DIVERGENCE IS NOTED OVER NE TEXAS.
THE SPEED MAX ON THE EAST SIDE OF LOW WILL MOVE NE TONIGHT AND SE
TX WILL LIE IN A RIGHT REAR QUAD BETWEEN 06-12Z WHICH IS THE SAME
TIME THE COLD FRONT WILL BE CROSSING THE AREA. WATER VAPOR IMAGERY
SHOWS A DISTURBANCE OVER NORTH CENTRAL MEXICO AND THIS FEATURE
SHOULD ARRIVE LATER TONIGHT AND WILL LIKELY HELP TRIGGER
SHRA/TSRA. RAP FCST SOUNDINGS SHOW PW VALUES SURGING TO 1.72 INCHES
WITH A K INDEX OF 39 AT 10Z. THE STRONG CAPPING INVERSION IN
PLACE MAGICALLY DISAPPEARS BETWEEN 07-08Z AND MAYBE THIS IS DUE TO
THE IMPROVING JET DYNAMICS. ALL SHORT TERM GUIDANCE IS BULLISH
WITH RAIN CHANCES OVERNIGHT SO RAISED POPS TO 80 PERCENT OVER THE
CWA. IF THE CAP HOLDS...THE AREA WILL PROBABLY GET JUST A BROKEN
LINE OF WEAK SHOWERS. CAPE/SHEAR LOOK LIMITED SO NOT EXPECTING
MUCH IN THE WAY OF SEVERE WEATHER BUT ONCE THE CAP ERODES...THERE
COULD BE SOME ISOLATED STRONG TO SEVERE STORMS ESPECIALLY TO THE
NE. CONDITIONS SHOULD DRY OUT QUICKLY ON THURSDAY IN THE WAKE OF
THE FRONT WITH SLIGHTLY COOLER TEMPS. 43
&&
.PREV DISCUSSION... /ISSUED 613 PM CDT WED MAR 23 2016/
AVIATION...
SHOWERS HAVE DEVELOPED UNDER THE CAPPING INVERSION AND EXPECT
THESE TO PERSIST THROUGH AT LEAST 04Z. A FAIRLY TIGHT PRESSURE
GRADIENT HAS LED TO BREEZY CONDITIONS. THESE WILL DIMINISH AS THE
PRESSURE GRADIENT RELAXES LATER THIS EVENING AND OVERNIGHT TONIGHT
AHEAD OF THE COLD FRONT. THE FRONT STILL LOOK ON TRACK TO MAKE IT
TO THE HOUSTON METRO AIRPORTS BETWEEN 11Z AND 14Z...AND OFF THE
COAST BETWEEN 15 AND 17Z. MVFR CONDITIONS ARE LIKELY AHEAD OF THE
FRONT ALONG WITH SHOWERS.
40
PREV DISCUSSION... /ISSUED 301 PM CDT WED MAR 23 2016/
DISCUSSION...
BREEZY SO FAR THIS AFTERNOON THOUGH IT APPEARS TO BE STARTING TO
RELAX WITH THE SLOW DEPARTURE OF THE 850 JET AXIS INTO NWLA/SWAR.
CLOUD COVER HAS BEEN MORE CHALLENGING TODAY...EXPECTED THAT AREAS
NEAR THE COAST WOULD POP OUT BUT 4-5000FT DECK EXPANDED IN
COVERAGE MORESO THAN EXPECTED. THIS HAS HELPED TO KEEP
TEMPERATURES IN THE MID-UPPER 70S.
DRY LINE HAS PUSHED OUT EAST TO NEAR A OKC-ABI-OZA LINE WITH
STRONG DOWNSLOPING GUSTY DRY CONDITIONS IN ITS WAKE WITH THE COLD
FRONT JUST HAVING MOVED INTO THE NW CORNER OF THE PANHANDLE. QUITE
THE BLIZZARD GOING ON WITH THE ASSOCIATED LOW STORM SYSTEM IN
NW KS/WRN NE. AS THIS STORM COMPLEX LIFTS OUT TOWARD LAKE MICHIGAN
THE COLD FRONT SHOULD PUSH SE AND INTO SETX NEAR CLL AROUND 3 AM
AND THROUGH THE METRO AREA BY 7-8 AM...GLS AROUND 9-11 AM. PRIOR
TO THE FROPA WINDS RELAX AND MAY HAVE A WINDOW FOR SOME FOG TO
DEVELOP PROBABLY IN A SWATH FROM COLUMBUS TO CROCKETT BETWEEN
MIDNIGHT AND 5 AM. NOT SURE YET HOW THICK IT MAY GET SO FOR NOW
WILL JUST WORD AS PATCHY BUT EVENING SHIFT MAY NEED TO EXPAND ON
THE FOG ISSUE. NEXT ISSUE WILL BE RAINFALL...12Z SOUNDING SHOW A
STRONG TO VERY STRONG CAP IN PLACE. MODELS PROG THIS CAP TO REMAIN
OVER MOST OF THE SW 1/3 TO 1/2 OF THE REGION. WITH THE FROPA
OCCURRING DURING THE OVERNIGHT HOURS CAPE APPEARS LIMITED AND
GIVEN THE STRONG CAP HAVE TRENDED POPS LOWER OVER THE AREAS FROM
BRENHAM TO FREEPORT SOUTHWESTWARD. AREAS NEAR CROCKETT-
GROVETON-LIVINGSTON HAVE THE BEST CHANCES FOR RAINFALL AND WILL
CONTINUE WITH 60-70 POPS FOR THOSE AREAS. QPF DOESN`T LOOK VERY
HIGH FOR ANY OF THE AREAS AND AMOUNTS WILL PROBABLY AVERAGE AROUND
0.10" OR LESS WITH SOME OF THE AREAS CLOSER TO WHERE THE CAP GETS
WEAKER IN THE NORTHEAST APPROACHING 0.25". WINDS SHOW A SHALLOW
LAYER WITH GOOD TURNING BUT SURFACE WINDS ARE S TO SSW (ANOTHER
GOOD SIGN OF CAPPING) SO AGAIN THOSE SAME AREAS IN THE NORTHEAST
HAVE A SLIGHTLY GREATER CHANCE OF SEEING ISOLATED TO SCATTERED
STRONG THUNDERSTORMS SOME WITH GUSTY WINDS AND POSSIBLY SOME SMALL
HAIL.
AFTER THE FROPA THE AREA DRIES OUT QUICKLY THURSDAY LATE MORNING
THROUGH THE AFTERNOON WITH MODERATE DEEP CAA ENDING BY EARLY
FRIDAY MORNING. THIS WILL BRING IN MUCH COOLER TEMPERATURES AFTER
TONIGHTS WARMTH. THE NEXT SYSTEM MOVES OUT INTO THE SOUTHERN
PLAINS SATURDAY/SUNDAY WHICH TURNS WINDS BACK TO THE SOUTHEAST
HERE AND SLIM RAIN CHANCES RETURN EASTER SUNDAY THANKS TO
UNFAVORABLE JET SCALE LIFT AND LIMITED MOISTURE RETURN. ANOTHER
SHOT OF COOL AIR ARRIVES SUNDAY AFTERNOON. A LOW PRESSURE SYSTEM
COMPARABLE TO OUR CURRENT ONE TAKES SHAPE OVER THE UTAH AREA
TUESDAY/WEDNESDAY WHICH SHOULD START THE MOISTURE PUMP GOING FROM
THE GULF RAMPING UP TEMPERATURES AND MOISTURE AND POSSIBLY GIVING
THE REGION A SHOT AT SOME SCATTERED SHOWERS.
45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 56 66 44 71 51 / 80 20 0 0 10
HOUSTON (IAH) 62 69 47 72 52 / 80 30 0 0 10
GALVESTON (GLS) 66 68 54 66 60 / 60 60 0 0 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 AM CDT THURSDAY FOR
THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT ADVISORY UNTIL 4 AM CDT THURSDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20
TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 10 PM CDT THIS EVENING
FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...43
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
624 PM CDT WED MAR 23 2016
.AVIATION...
THE COMBINATION OF AN UPPER TROUGH...A DRY LINE AND A COLD FRONT
WILL LEAD TO A ROUND OF CONVECTION THIS EVENING...
CONVERGENCE ALONG A DRY LINE HAS LED TO ISOLATED THUNDERSTORM
DEVELOPMENT NORTH OF THE DFW AREA OVER THE PAST HOUR OR SO. HI-RES
MODEL GUIDANCE INDICATES THAT ACTIVITY WILL BACK-BUILD
SOUTHWESTWARD TOWARDS THE KMWL AREA OVER THE NEXT COUPLE OF HOURS
AS STRONGER FORCING ASSOCIATED WITH THE UPPER TROUGH ARRIVES FROM
THE WEST. FOR SIMPLICITY WE WILL BEGIN THE METROPLEX TAFS WITH
VCTS. THE FRONT WILL LIKELY OVERTAKE THE DRYLINE ABOUT THE SAME
TIME STORMS BEGIN TO AFFECT THE DALLAS-FORT WORTH AREA...WHICH
SHOULD BE IN THE THE 02-04Z TIME FRAME. ACTIVITY MAY START OFF
ISOLATED IN NATURE...WITH STORMS THEN FORMING INTO A LINE AND
DEVELOPING SOUTHEASTWARD ACROSS THE REGION WITH THE FRONT. TIMING
OF THE ONSET OF CONVECTION IN THE WACO AREA WILL PROBABLY BE
AROUND 3 HOURS AFTER THE DFW AREA...OR BEGINNING AROUND MIDNIGHT
LOCAL. GUSTY NORTHWEST WINDS AND VFR CONDITIONS ARE EXPECTED
FOLLOWING THE PASSAGE OF THE FRONT.
30
&&
.UPDATE.../1148 AM CDT/
AN UPPER LEVEL LOW IS CURRENTLY MOVING INTO WESTERN KANSAS WITH
ITS ATTENDANT SURFACE LOW ALSO MOVING ACROSS KANSAS. A DRYLINE
EXTENDS FROM THE SURFACE LOW SOUTH...WITH THE LEADING EDGE NEAR A
VERNON TO SWEETWATER TO OZONA LINE. THE DRYLINE WILL CONTINUE
MIXING EAST...STALLING ACROSS NORTH TEXAS AROUND MID- AFTERNOON AS
THE LOWER AND MID LEVEL WINDS BECOME MORE SOUTHWESTERLY WHILE THE
UPPER LEVEL TROUGH MOVES EAST. WHERE THE DRYLINE STALLS REMAINS
THE MAIN CHALLENGE FOR THE FORECAST THE REMAINDER OF THE DAY. THE
HI RES MODELS STALL THE DRYLINE FURTHER WEST THAN PREVIOUSLY
THOUGHT AND HAVE UPDATED THE FORECAST TO REFLECT THIS CHANGE.
THE LOCATION OF THE DRYLINE AND WHERE IT STALLS WILL HAVE IMPACTS
ON THE LOCATION OF STORM DEVELOPMENT LATER TODAY. LATEST MODEL
GUIDANCE SUGGESTS THE DRYLINE WILL STALL NEAR A GAINESVILLE TO
GOLDTHWAITE LINE LATE THIS AFTERNOON. THE RAP HAS BEEN
CONSISTENTLY DEVELOPING ISOLATED CONVECTION ALONG THE DRYLINE
ALONG AND NORTH OF INTERSTATE 20 BETWEEN 22-23Z /5-6 PM CDT/ AND
NOW THE HRRR IS DEVELOPING CONVECTION TOO IN THE SAME GENERAL
LOCATION AND TIME. FORECAST SOUNDINGS FROM THE RAP SHOW THE CAP
WEAKENING ALONG THE DRYLINE ALLOWING FOR CONVECTIVE INITIATION AND
HAVE ADJUSTED THE AFTERNOON POPS ACCORDINGLY FOR THIS POTENTIAL
ALONG AND WEST OF A BOWIE TO MERIDIAN LINE. STILL KEPT THE POPS
LOW AT 20 PERCENT AS ANY STORMS DURING THE 4-6 PM TIME FRAME
SHOULD BE ISOLATED BUT THESE STORMS COULD BE SEVERE. CAPE VALUES
WILL BE BETWEEN 1500-2000 J/KG WITH STRONG BULK SHEAR VALUES. MAIN
THREATS WILL BE LARGE HAIL AND DAMAGING WINDS BUT AN ISOLATED
TORNADO WILL ALSO BE POSSIBLE.
AFTER 6-7 PM...THE COLD FRONT WILL START TO OVERTAKE THE DRYLINE
FROM NORTH TO SOUTH AND A NARROW BAND OF STORMS ALONG THE
FRONT/DRYLINE IS EXPECTED TO DEVELOP AS THIS HAPPENS. WITH THE
LIKELIHOOD THAT THE DRYLINE WILL BE WEST OF INTERSTATE
35...EXPANDED THE EVENING POPS WEST AS WELL BUT THE BEST STORM
CHANCES WILL BE ALONG AND EAST OF INTERSTATE 35. SEVERE STORMS
WILL AGAIN BE POSSIBLE WITH A THREAT FOR LARGE HAIL...DAMAGING
WINDS...AND ISOLATED TORNADOES IN THE EVENING HOURS BUT THE MAIN
THREAT MAY TRANSITION TO STRONG WINDS LATER IN THE EVENING AND
OVERNIGHT IF THE STORMS BECOME LINEAR ALONG THE FRONT...SIMILAR TO
A SQUALL LINE. OVERNIGHT...THE SEVERE THREAT WILL LOWER BUT WILL
STILL BE POSSIBLE. THE STORMS SHOULD BE EAST AND SOUTHEAST OF THE
AREA BY DAYBREAK AS THE FRONT MOVES OUT OF CENTRAL TEXAS.
&&
.PREV DISCUSSION... /ISSUED 347 PM CDT WED MAR 23 2016/
FOR THE REMAINDER OF TODAY AND TONIGHT...NO SIGNIFICANT CHANGES
ARE EXPECTED FROM THE UPDATE ISSUED AROUND MIDDAY AND HAVE
APPENDED THE UPDATE DISCUSSION BELOW FOR REFERENCE. BOTH THE RED
FLAG WARNING AND WIND ADVISORY WILL REMAIN IN EFFECT TROUGH 7 PM
CDT EVEN THOUGH MANY SITES ARE NOT CONSISTENTLY MEETING CRITERIA.
THE THREAT FOR FIRES AND STRONG GUSTY WINDS WILL CONTINUE INTO THE
EVENING HOURS.
WE CONTINUE TO TRACK THE LOCATION OF THE DRYLINE...VISIBLE ON
AREA RADARS...WHICH AT 3 PM WAS LOCATED NEAR A LINE FROM OKLAHOMA
CITY TO GRAHAM TO FORT STOCKTON. SOME CUMULUS CLOUDS HAVE BEEN
DEVELOPING ALONG THE DRYLINE FROM OLNEY/GRAHAM TO ABILENE BUT
THERE IS LITTLE VERTICAL EXTENT TO THESE CLOUDS AND NO CONVECTIVE
DEVELOPMENT. ACARS SOUNDINGS AT KDFW AIRPORT INDICATE THE CAP HAS
WEAKENED BUT IS STILL IN PLACE. HOWEVER...BY 22-23Z...THE HRRR
CONTINUES TO DEVELOP CONVECTION NEAR THE I-35 CORRIDOR AND RAPIDLY
INCREASES THE INTENSITY OF THESE STORMS WHICH WOULD BE EXPECTED
GIVEN THE UNSTABLE ENVIRONMENT AND SUFFICIENT SHEAR FOR SUPERCELLS
IF THE CAP CAN BE WEAKENED/ERODED.
THE COLD FRONT CAN ALSO BE TRACKED ON VISIBLE SATELLITE IMAGERY
AND AREA RADARS SWEEPING DOWN THE TEXAS PANHANDLE AND WESTERN
OKLAHOMA. AS THE FRONT OVERTAKES THE DRYLINE IN OUR AREA THIS
EVENING AND LARGE SCALE LIFT INCREASES AS THE BASE OF THE UPPER
LEVEL TROUGH APPROACHES FROM THE WEST...ADDITIONAL STORMS ARE
EXPECTED TO DEVELOP ALONG THIS FRONT/DRYLINE INTERACTION AND
POSSIBLY THE SOUTHERN EXTENT OF THE DRYLINE. AT FIRST...THESE
STORMS MAY FORM A BROKEN LINE BUT ARE EXPECTED TO CONGEAL INTO A
MORE SOLID LINE AS THE FRONT PROGRESSES SOUTHEAST THROUGH THE
AREA. BY DAYBREAK THURSDAY MORNING...THE STORMS SHOULD HAVE EXITED
THE AREA LEAVING COOL AND BREEZY CONDITIONS IN THE WAKE OF THE
FRONT.
THE MAIN THREATS WITH ANY STORMS THAT DEVELOP LATE THIS AFTERNOON
AND EARLY EVENING WILL BE LARGE HAIL...DAMAGING WINDS...AND
ISOLATED TORNADOES. FOR THE STORMS ALONG THE FRONT LATER...INITIAL
THREATS WILL ALSO BE LARGE HAIL...DAMAGING WINDS...AND ISOLATED
TORNADOES. HOWEVER...AS THE STORMS CONGEAL INTO A LINE...THE MAIN
THREAT MAY BECOME DAMAGING WINDS...BUT THERE WILL STILL BE A LOWER
THREAT FOR HAIL AND ISOLATED TORNADOES GIVEN THE SHEAR VALUES
AHEAD OF THE FRONT.
TEMPERATURES ON THURSDAY WILL BE COOLER WITH HIGHS IN THE 60S BUT
IT WILL FEEL COOLER THAN THAT WITH BREEZY NORTH WINDS OF 10 TO 20
MPH AND GUSTS UP TO 30 MPH. BROAD TROUGHING IN THE MID LEVELS OF
THE ATMOSPHERE WILL CONTINUE BUT WEAK RIDGING FROM THE SURFACE TO
H700 AND A RETURN OF SOUTH WINDS FRIDAY WILL RESULT IN WARMING
TEMPERATURES FRIDAY AND SATURDAY. FRIDAY AND SATURDAY ARE EXPECTED
TO BE PLEASANT...SUNNY...AND DRY BUT IT WILL BE A LITTLE BREEZY IN
SOME AREAS WITH WINDS OF 10-15 MPH AND SLIGHTLY HIGHER GUSTS.
ANOTHER SHORTWAVE WILL MOVE THROUGH THE BROAD UPPER LEVEL TROUGH
AND ACROSS THE PLAINS SATURDAY NIGHT SENDING ANOTHER COLD FRONT
INTO NORTH AND CENTRAL TEXAS ON SUNDAY. THERE ARE TIMING
DIFFERENCES WITH THE FRONT BUT THE LATEST TRACK HAS IT MOVING
THROUGH THE REGION LATE SATURDAY NIGHT AND SUNDAY MORNING. THERE
MAY BE SOME WEAK INSTABILITY AHEAD OF THE FRONT FOR A FEW STRONG
STORMS BUT CONFIDENCE IN THIS IS LOW AND WE WILL CONTINUE TO
MONITOR THE INSTABILITY AND TIMING LEADING UP TO THIS NEXT SYSTEM.
SUNDAY WILL BE A COOL DAY FOR MOST WITH TEMPERATURES DEPENDING ON
THE TIMING OF THE FRONT.
EARLY NEXT WEEK WILL BE DRY WITH INCREASING TEMPERATURES BUT
ANOTHER STRONG UPPER LEVEL SYSTEM MAY DEVELOP IN THE WESTERN CONUS
BY MIDWEEK BRINGING ADDITIONAL RAIN CHANCES BY MID TO LATE WEEK.
JLDUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 48 64 44 72 52 / 50 5 0 0 5
WACO, TX 50 66 40 72 49 / 60 5 0 0 5
PARIS, TX 47 61 40 68 47 / 60 5 0 0 5
DENTON, TX 46 63 39 70 50 / 40 5 0 0 5
MCKINNEY, TX 47 62 39 69 49 / 50 5 0 0 5
DALLAS, TX 48 64 44 72 52 / 50 5 0 0 5
TERRELL, TX 48 63 41 70 49 / 60 5 0 0 5
CORSICANA, TX 51 65 43 71 50 / 60 10 0 0 5
TEMPLE, TX 52 66 42 71 49 / 50 5 0 0 5
MINERAL WELLS, TX 46 65 39 73 50 / 30 5 0 0 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR TXZ091>095-100>107-
115>123-129>135-141-143>147-157>161-174.
RED FLAG WARNING UNTIL 7 PM CDT THIS EVENING FOR TXZ091-092-
100>102-115>117-129>132-141>143.
&&
$$
30
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
600 PM CDT WED MAR 23 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 300 PM CDT WED MAR 23 2016
HAVE BEEN MONITORING THE CURRENT FORECAST VERSUS OBSERVATIONS AND
THE LATEST MODEL DATA. STRONG FRONTOGENETIC BAND ANCHORED AT
600-700MB HAS NOW SHIFTED NORTH OF I-90 AS FORECAST WELL BY THE
RAP MODEL GUIDANCE. AS EVENING APPROACHES...A MORE SW-NE ORIENTED
BAND WILL BECOME ESTABLISHED FROM SOUTHEAST MN THROUGH CENTRAL
WI. THIS IS THE BAND CURRENTLY SEEN ON RADAR OVER MN...WHICH WILL
INTENSIFY AND DROP SOUTHEAST. GETTING SOME MIX OF SLEET AND
FREEZING DRIZZLE S-SW OF LA CROSSE PER OBSERVATIONS AND DUAL POL
CC PRODUCT.
VERY GOOD AND CONSISTENT DETERMINISTIC GUIDANCE COMING IN FOR THE
EVOLUTION OF THIS SYSTEM. OVERALL THE HEAVIEST LIQUID AMOUNTS LINE
UP WELL WITH OUR ONGOING FORECAST. THE LATEST WPC GUIDANCE PLACES
1.3 INCHES OF LIQUID IN THE FRONTOGENETIC BAND. SNOW RATIOS WILL
PROBABLY BE A BIG DETERMINISTIC FACTOR IN THE AMOUNT OF
SNOW...WITH 10-11 TO 1 PROBABLY ABOUT RIGHT.
SOUTH OF THE FRONTOGENETIC BAND...LOSS OF ICE ALOFT WILL CAUSE A
FREEZING DRIZZLE ENVIRONMENT. THIS MAY BE AROUND SOME HOURS UNTIL
THE CONVECTIVE SURGE THIS EVENING AND OVERNIGHT...WHERE DEEP ICE
WILL AGAIN ENTER THE AREA. THE WARM LAYER ALOFT IN THE SOUTH
REMAINS WARM ENOUGH FOR COMPLETE MELTING AS WELL AND COLD AIR IS
UNDERCUTTING THIS WARM LAYER LATER TONIGHT. WHILE THE ADVISORY
COVERS SOME OF THIS AREA...WE WILL BE WATCHING THE HIGHWAY 18
CORRIDOR FOR MORE ICING OVERNIGHT...AN ADVISORY MAY BE NEEDED.
TEMPERATURES REMAIN ABOVE FREEZING FOR A PERIOD TONIGHT...SO
ICING SHOULD BE MINIMIZED THERE. THE NEW FORECAST HAS ALSO SLOWED
THE SNOW EXIT ON THURSDAY MORNING...WITH ACCUMULATING SNOW STILL
IN WISCONSIN FOR THE COMMUTE HOURS.
THE ONLY OTHER CONCERN TO SHARE IS THE TREND IN THE LATEST HRRR
GUIDANCE WITH A FURTHER SOUTH /NERN IA-SWRN WI/ SOLUTION TO
CONVECTIVE ACTIVITY THIS EVENING...AND THE DIMINISHING
FRONTOGENETIC SW-NE BAND OVER SERN MN INTO CENTRAL WI. COMPARING
TO HOP WRF SOLUTIONS AND OTHER MESOMODELS...THINKING THE HRRR IS
AN OUTLIER SOLUTION AT THIS TIME.
BOTTOM LINE IS TRAVEL WILL GET PRETTY TREACHEROUS TONIGHT WITH
CONVECTIVE SNOW RATES OF 1-3 INCHES PER HOUR IN FRONTOGENETIC
BAND. INSTABILITY IS ALREADY SEEN IN THE RADAR IMAGERY WITH VERY
SHOWERY LOOKS TO ELEMENTS SOUTH OF THE MAIN SNOW BAND. ALSO SEEING
100 C-G LIGHTNING STRIKES ACROSS NEBRASKA...SO WE COULD BE IN FOR
A THUNDERSNOW TONIGHT. HAVE KEPT THE 10-14 INCH SNOW BAND FROM
SERN MN INTO CENTRAL WI. ICING AND SLEET WILL MIX IN TO THE SOUTH
WITH MAYBE A TENTH OF ICING.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 300 PM CDT WED MAR 23 2016
SIGNALS CONTINUE FOR SATURDAY WITH LIGHT PRECIPITATION EXPECTED
WITH SHORTWAVE ENERGY. HAVE CONTINUED PREVIOUS FORECAST WITHOUT
CHANGES...WITH RAIN SHOWERS LOOKING MORE LIKELY IN THE AFTERNOON
IN WISCONSIN.
MONITORING CONTINUES FOR THE SUNDAY-MONDAY TIME FRAME ON MORE
SIGNIFICANT ENERGY SHIFTING THROUGH THE BROAD LONG WAVE TROUGH
THROUGH THE CENTRAL U.S. BOTH THE 23.00Z AND 23.12Z ECMWF AND
23.12 CANADIAN SUGGEST THIS SHORTWAVE TROUGH ENERGY IS STRONGER
THAN THE GFS SYSTEM OF SOLUTIONS...WITH A SLIGHT NEGATIVE TILT AND
WELL FORMED DEFORMATION PRECIPITATION SHIELD WHICH LOOKS TO BE
SNOW ON THE NORTHWEST SIDE. THIS COULD AFFECT SOUTHWEST OR CENTRAL
WI DEPENDING ON THE TREND. THE PROGRESSIVE PREVIOUS TWO RUNS OF
THE GFS HAVE NO WEATHER FOR THIS TIME FRAME. HAVE CARRIED LOW
RANGE CHANCES FOR PRECIPITATION AT THIS TIME.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 600 PM CDT WED MAR 23 2016
WINTER STORM IMPACTS KRST/KLSE INTO THU MORNING...WITH IFR/LIFR CIGS
AND VSBYS. EXPECT THE BULK OF THE ACCUMULATING SNOWS TO END BETWEEN
12-15Z THU...WITH GRADUALLY IMPROVEMENT IN THE CIGS DURING THE
AFTERNOON/EVENING.
RADAR POINTS TO A BREAK FROM THE HEAVIER PCPN FOR A FEW HOURS EARLY
THIS EVENING...WITH THE NEXT SLUG OF PCPN MOVING IN BETWEEN 03-06Z.
THAT WILL BE SNOW...AND EXPECT VSBYS FROM 1/4 TO 1SM FOR MOST OF THE
OVERNIGHT. HOURLY SNOWFALL RATES OF 1-2 INCHES POSSIBLE...WITH
ACCUMS BY 12Z THU FROM 6 TO 8 WET INCHES. CAN/T RULE OUT A CRACK OF
THUNDER...BUT NOT ENOUGH CONFIDENCE TO ADD TO FORECAST.
WINDS WILL STAY RELATIVELY STRONG AND GUSTY THROUGH THE
OVERNIGHT...BUT LITTLE IF ANY BLOWING/DRIFTING DUE TO THE WET NATURE
OF THE SNOW.
&&
.HYDROLOGY...
ISSUED AT 300 PM CDT WED MAR 23 2016
DUE TO THE EXCESSIVE RAINFALL FROM LAST WEEK...AREA RIVERS
CONTINUE TO RUN HIGHER THAN NORMAL. FLOOD WARNINGS CONTINUE FOR
THE MISSISSIPPI RIVER AT BOTH GUTTENBERG AND MCGREGOR AND THE
WISCONSIN RIVER AT MUSCODA.
SNOW MELT FROM THIS SYSTEM MAY PROLONG ELEVATED LEVELS IN AREA
RIVERS. ONLY THOSE RIVERS NEAR FLOOD STAGE WOULD POSSIBLY RE-ENTER
FLOOD STAGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL NOON CDT THURSDAY
FOR WIZ041>044-053.
WINTER STORM WARNING UNTIL NOON CDT THURSDAY FOR WIZ017-029-
032>034.
WINTER WEATHER ADVISORY UNTIL NOON CDT
THURSDAY FOR WIZ054-055.
MN...WINTER STORM WARNING UNTIL NOON CDT THURSDAY
FOR MNZ094>096.
WINTER STORM WARNING UNTIL NOON CDT THURSDAY FOR MNZ079-086>088.
IA...WINTER STORM WARNING UNTIL NOON CDT THURSDAY
FOR IAZ008>010-018-019.
WINTER WEATHER ADVISORY UNTIL NOON CDT
THURSDAY FOR IAZ011.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...RIECK
HYDROLOGY...BAUMGARDT
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1206 AM MDT THU MAR 24 2016
.UPDATE...
ISSUED AT 754 PM MDT WED MAR 23 2016
STRONG LOW WILL CONTINUE TO LIFT NORTHEAST OVER THE CENTRAL PLAINS
AND AWAY FROM COLORADO. SNOW AND WINDS WILL CONTINUE TO RAPIDLY
DECREASE THE REST OF THE EVENING ACROSS NORTHEAST COLORADO. EXPECT
SNOW TO END LATE THIS EVENING IN THE FAR NORTHEAST CORNER OF THE
STATE. LOOKS THERE WILL BE ENOUGH MOISTURE EMBEDDED IN THE
NORTHWEST FLOW BEHIND THE EXITING SYSTEM FOR SNOW SHOWERS OVER THE
MOUNTAINS TONIGHT AND THURSDAY. INCREASED POPS SOME FOR THIS.
ACCUMULATIONS WILL BE LIGHT...LESS THAN 2 INCHES.
LET ALL THE ADVISORIES AND WARNINGS EXPIRE EXCEPT FOR THE PLAINS
EAST OF A LINE FROM LIMON TO STERLING. THESE WARNING OVER FAR
EASTERN COLORADO ARE SET TO EXPIRE AT 10 PM. AS WINDS AND SNOW
DECREASE...CONDITIONS WILL CONTINUE TO IMPROVE THIS EVENING AND
PLAN ON EXPIRING THIS BLIZZARD WARNING AT 10 PM.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 243 PM MDT WED MAR 23 2016
VERTICALLY STACKED LOW NOW OVER NORTHWEST KANSAS WILL CONTINUE TO
MOVE EAST OF THE REGION. STRONG FORCING ON THE BACKSIDE OF THE LOW
WILL CONTINUE TO BRING HEAVY SNOW AND STRONG WINDS THE NORTHEAST
PLAINS THROUGH AROUND MID EVENING. ALONG THE FRONT RANGE...WINDS
ARE STARTING TO TURN WESTERLY IN AND NEAR THE FOOTHILLS AND SNOW
HAS STARTED TO DECREASE. EXPECT SNOW TO CONTINUE TO DECREASE AND
END LATE THIS AFTERNOON OR EARLY EVENING ALONG THE FRONT RANGE.
EXTENDED THE WARNINGS OVER THE PLAINS WHERE IT APPEARS SNOW AND
WINDS WILL CONTINUE INTO THE EVENING HOURS.
SNOW IS EXPECTED TO END ACROSS THE AREA BY MIDNIGHT...EXCEPT FOR A
FEW SNOW SHOWERS IN THE MOUNTAINS. COOLED TEMPERATURES FOR
THURSDAY DUE TO THE EXTENSIVE SNOW COVER. SNOW SHOWERS WILL
REMAIN POSSIBLE IN THE MOUNTAINS THURSDAY. ANY NEW SNOWFALL IS
EXPECTED TO BE LIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 319 AM MDT WED MAR 23 2016
DUE TO WEATHER AND COMPUTER ISSUES...VERY LITTLE TO NO CHANGES
WERE MADE. HERE IS THE PREVIOUS DISCUSSION FROM EARLIER THIS
MORNING.
A DISTURBANCE IN THE NW FLOW WILL PUSH IN FRIDAY TO INCREASE SNOW
FOR THE MOUNTAINS BY MORNING...THEN BRING A CHANCE FOR RAIN
SHOWERS OVER THE PLAINS IN THE AFTERNOON. TEMPERATURES SHOULD
WARM FURTHER ON FRIDAY BEFORE THE EXPECTED COLD FRONT PUSHES DOWN
THAT EVENING WITH UPSLOPE CONDITIONS EXPECTED OVER THE PLAINS.
LOOK FOR SNOW TO SPREAD ACROSS THE PLAINS WITH ACCUMULATING SNOW
EXPECTED THROUGH SATURDAY MORNING. THE SYSTEM ALOFT WILL LIKELY BE
AN OPEN WAVE...THOUGH LATEST GFS RUN SLOWS THE KEEPS IT DEEPER...
WITH MODERATE QG LIFT. AMOUNTS ARE HARD TO PINPOINT DOWN AT THIS
POINT...HOWEVER IT WILL BE LESS THAN WHAT IS EXPERIENCED TODAY.
LOCATIONS FAVORED IN UPSLOPE PATTERNS WILL SEE THE HIGHEST TOTALS.
SATURDAYS TEMPERATURES WILL AGAIN BE BACK INTO THE 30S TO LOW 40S
AT BEST.
UPPER RIDGING WILL THEN PUSH INTO THE AREA SUNDAY THEN
SOUTHWESTERLY FLOW ALOFT IS EXPECTED MONDAY AND TUESDAY AHEAD OF
THEN NEXT SYSTEM. LOOK FOR WARMER AND DRIER WEATHER FOR THESE
THREE DAYS...EXCEPT FOR A INCREASING MOISTURE PUSHING IN TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1206 AM MDT THU MAR 24 2016
CLOUDS HAVE SCATTERED OUT ALLOWING FOR PATCHY...DENSE AT TIMES...FOG
FORM IN AREAS OVER THE WESTERN SUBURBS AS WELL AS DOWN OVER THE
PALMER DIVIDE. KBJC HAS ALREADY SEEN VIS OF 1/4 MILE...BUT HAS
SINCE IMPROVED. THERE IS A CHANCE FOR THIS FOG TO PUSH INTO KDEN
AND KAPA OVER THE NEXT FEW HOURS...AS THE HRRR SHOWS. HOWEVER THE
RAP AND GFS...STILL KEEP THE BOUNDARY LAYER TOO DRY FOR FOG. WILL
MENTION VCFG AT THIS TIME DUE TO THE DRAINAGE WINDS MIXING THE
DRIER AIR. IT SEEMS AS THOUGH THE CHANCE WILL BE DONE BY 12Z WITH
ONLY HIGH CLOUDS REMAINING. WINDS SHOULD STAY DRAINAGE/SOUTHERLY
THROUGH THURSDAY NIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MEIER
SHORT TERM...MEIER
LONG TERM...KRIEDERMAN
AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
353 AM EDT THU MAR 24 2016
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND OVER THE REGION TODAY. A COLD FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON FRIDAY...LIKELY STALLING JUST SOUTH
AND EAST OF THE REGION THROUGH SATURDAY. UNSETTLED WEATHER IS
EXPECTED SUNDAY...BEFORE A COLD FRONT PUSHES THROUGH THE AREA
MONDAY. DRY HIGH PRESSURE WILL THEN BUILD OVER THE REGION THROUGH
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
UPPER RIDGING THAT HAS BEEN PRESENT ACROSS THE SOUTHEAST U.S. FOR
THE PAST SEVERAL DAYS WILL FINALLY BREAK DOWN TODAY IN RESPONSE
TO A POTENT STORM SYSTEM APPROACHING THE GREAT LAKES REGION.
ATLANTIC HIGH PRESSURE LOOKS TO HOLD ACROSS SOUTHEAST SOUTH
CAROLINA AND SOUTHEAST GEORGIA FOR FOR MUCH OF THE DAY BEFORE
FINALLY RETREATING TONIGHT IN RESPONSE TO AN APPROACHING COLD
FRONT. EXPECT DRY CONDITIONS TO PREVAIL FOR MOST AREAS THROUGH
SUNSET WITH MODELS SHOWING A STRONG SUBSIDENCE INVERSION HOLDING
JUST UNDER 750 HPA. THERE ARE SIGNALS IN BOTH THE SYNOPTIC AND
HIGHER RESOLUTION MESOSCALE MODELS THAT A NORTH-SOUTH ORIENTED
CONVERGENT MOISTURE CHANNEL COULD SETUP JUST OFF THE MIDDLE SOUTH
CAROLINA COAST LATER THIS MORNING. THIS COULD GENERATED ISOLATED
SHOWERS ACROSS THE COASTAL WATERS...SOME OF WHICH COULD MOVE
ONSHORE ACROSS THE MIDDLE/UPPER PORTIONS OF CHARLESTON COUNTY.
UPDRAFTS WITH THESE SHOWERS WILL BE SEVERELY CURTAILED GIVEN THE
PRESENCE OF THE STRONG SUBSIDENCE INVERSION...SO TSTMS APPEAR
UNLIKELY ATTM. WILL CARRY SLIGHT CHANCE POPS FOR CENTRAL AND UPPER
PORTIONS OF CHARLESTON COUNTY AS WELL AS EASTERN BERKELEY COUNTY
FOR TODAY WITH DRY CONDITIONS ELSEWHERE.
TEMPERATURES ARE POISED TO RISE QUICKLY AFTER SUNRISE WITH HIGHS
LIKELY TO WARM INTO THE LOWER 80S ALONG/WEST OF THE I-95
CORRIDOR. A BIT MORE CLOUD COVER AND POSSIBLY A FEW SHOWERS WILL
HELP LIMIT HIGHS TO THE UPPER 70S ACROSS MUCH OF THE CHARLESTON
TRI-COUNTY AREA AWAY FROM THE COAST. HIGHS AT THE BEACHES WILL
ONCE AGAIN BE LIMITED TO THE MID-UPPER 60S...EXCEPT AROUND 70 FOR
SOME GEORGIA BEACHES.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...
TONIGHT...A COLD FRONT WILL MOVE STEADILY EAST ACROSS THE DEEP
SOUTH OVERNIGHT AND WILL BE VERY NEAR THE FAR WESTERN ZONES BY
SUNRISE THURSDAY. NO SIGNIFICANT FORCING IS NOTED IN THE VARIOUS
00Z MODEL PROGNOSTICATIONS AND WITH THE POSSIBILITY OF CONVECTION
MOVING ACROSS THE NORTHEASTERN GULF POTENTIALLY DISRUPTING MOISTURE
TRANSPORT AHEAD OF THE FRONT...THE PROSPECTS FOR SIGNIFICANT
RAINFALL WILL REMAIN LOW THROUGH THE NIGHT. WILL CARRY 20-30
PERCENT POPS ACROSS THE FAR WESTERN ZONES BETWEEN MIDNIGHT AND
SUNRISE TO ACCOUNT FOR POSSIBLE SHOWER ACTIVITY ASSOCIATED WITH
THE FRONT ITSELF IMPACTING THOSE AREAS. IT WILL A WARM NIGHT WITH
LOWS ONLY DROPPING INTO THE MID 60 FOR MOST LOCATIONS.
FRIDAY...HIGH PRESSURE WILL RETREAT OVER THE WESTERN ATLANTIC AS A
COLD FRONT SLOWLY SHIFTS OVER THE AREA AND THEN STALLS SOUTH AND
EAST OF THE REGION LATE FRIDAY NIGHT. CHANCES OF SHOWERS AND A FEW
THUNDERSTORMS WILL BE POSSIBLE FOR MOST AREAS AS FROPA OCCURS.
SEVERE WEATHER IS NOT ANTICIPATED GIVEN LIMITED INSTABILITY DURING
THE TIME OF FROPA. DESPITE INCREASING CLOUD COVER AND PRECIP
ACTIVITY...HIGHS SHOULD PEAK IN THE LOW/MID 70S...WARMEST IN
SOUTHEAST GEORGIA.
SATURDAY AND SUNDAY...HIGH PRESSURE WILL ATTEMPT TO WEDGE SOUTHWARD
OVER NORTHERN AREAS ON SATURDAY BEHIND A COLD FRONT THAT STALLS JUST
SOUTH AND EAST OF THE AREA. HOWEVER...THE PATTERN WILL BE SHORT-
LIVED AS LOW PRESSURE BEGINS TO DEVELOP TO THE WEST/SOUTHWEST AND
SLOWLY TRACKS TOWARD THE SOUTHEAST UNITED STATES EARLY NEXT WEEK.
CHANCES OF SHOWERS WILL REMAIN IN THE FORECAST ON SATURDAY. A FEW
THUNDERSTORMS WILL ALSO BE POSSIBLE IN SOUTHEAST GEORGIA WHERE
LIMITED INSTABILITY DEVELOPS. HIGH TEMPS WILL RANGE IN THE UPPER 60S
NORTH...TO LOWER 70S SOUTH. BY SUNDAY...A GREATER CHANCE OF SHOWERS
AND THUNDERSTORMS WILL BE POSSIBLE AS A SERIES OF H5 SHORTWAVES
SHIFT OVER DEEP MOISTURE RESIDING IN THE SOUTHEASTERN UNITED STATES.
TEMPS SHOULD ALSO BE A FEW DEGREES WARMER THAN SATURDAY AS A
SOUTHERLY SFC FLOW RETURNS TO THE AREA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
A WET PATTERN WILL PERSIST INTO EARLY NEXT WEEK AS A SERIES OF H5
SHORTWAVES PASS OVER THE SOUTHEASTERN UNITED STATES IN ADVANCE OF A
LONGWAVE TROUGH. SHOWER AND THUNDERSTORM COVERAGE SHOULD BE GREATEST
SUNDAY INTO EARLY MONDAY WHEN DEEP MOISTURE CHARACTERIZED BY PWATS
BETWEEN 1.50 TO 1.75 INCHES ADVECTS INTO THE REGION AHEAD OF A COLD
FRONT APPROACHING FROM THE WEST. PRECIP ACTIVITY WILL LIKELY COME TO
AN END ONCE COLD FROPA OCCURS ON MONDAY. DRY AND COOLER HIGH
PRESSURE WILL THEN FOLLOW THE FRONT TUESDAY AND WEDNESDAY...WITH
HIGH TEMPS IN THE LOWER 70S AND OVERNIGHT LOWS IN THE UPPER 40S TO
LOWER 50S WELL INLAND. A WARMING TREND SHOULD THEN OCCUR ON THURSDAY
AS HIGH PRESSURE SLIDES OFFSHORE IN ADVANCE OF THE NEXT LOW PRESSURE
SYSTEM APPROACHING THE SOUTHEASTERN UNITED STATES.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
VFR. LOW-LEVEL JET HAS SHOWN SIGNS OF WEAKENING OVER THE PAST 1-2
HOURS WITH THE LATEST RAP PROGS SHOWING LOW-LEVEL WIND SHEAR
CRITERIA DIMINISHING BY 06Z. WILL DROP MENTION FROM BOTH KCHS AND
KSAV WITH THE 06Z TAF CYCLE. SHALLOW GROUND FOG IS POSSIBLE JUST
BEFORE SUNRISE AT BOTH TERMINALS...BUT NO IMPACTS ARE ANTICIPATED.
COULD SEE A FEW SHOWERS NEAR THE KCHS TERMINAL LATER THIS MORNING
AS A NORTH- SOUTH ORIENTED MOISTURE CHANNEL SETS UP JUST OFF THE
LOWER SOUTH CAROLINA COAST. ANY ACTIVITY SHOULD REMAIN EAST OF THE
TERMINAL.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS ARE LIKELY FRIDAY
WITH SHOWERS AND THUNDERSTORMS DEVELOPING ALONG A PASSING COLD
FRONT. FLIGHT RESTRICTIONS COULD PERSIST THROUGH THE WEEKEND AND
INTO EARLY NEXT WEEK UNTIL A COLD FRONT PUSHES THROUGH THE REGION
ON MONDAY.
&&
.MARINE...
TONIGHT...SOUTHERLY WIND REGIME WILL REMAIN IN PLACE TODAY AS THE
AREA REMAINS ALONG THE WESTERN FLANKS OF ATLANTIC HIGH PRESSURE.
WILL LIKELY SEE ANOTHER GUSTY SEA BREEZE CIRCULATION IMPACT THE
LAND/SEA INTERFACE AND CHARLESTON HARBOR AGAIN THIS
AFTERNOON...BUT SPEEDS LOOK TO REMAIN A BIT LOWER THAN YESTERDAY.
COULD SEE A FEW HOURS OF 15 KT IN THE CHARLESTON HARBOR WITH 10-15
KT ELSEWHERE. SEAS WILL AVERAGE 2-3 FT.
TONIGHT...LOW-LEVEL JETTING WILL YIELD AN ENHANCED WIND FIELD
ACROSS THE WATERS TONIGHT AS A COLD FRONT APPROACHES FROM THE
WEST. SPEEDS LOOK TO PEAK 15-20 KT FOR MOST LEGS...ALTHOUGH THERE
COULD BE A FEW HOURS OF SPEEDS NEAR 20 KT ACROSS PARTS OF THE
GEORGIA OFFSHORE AND CHARLESTON COUNTY LEGS AFTER MIDNIGHT.
CONDITIONS LOOK MARGINAL FOR A SMALL CRAFT ADVISORY...ESPECIALLY
FOR THE GEORGIA OFFSHORE WATERS...SO FLAGS WILL NOT BE ISSUED WITH
THIS FORECAST CYCLE. SEAS WILL BUILD TO 3-5 FT.
FRIDAY THROUGH TUESDAY...MARGINAL SMALL CRAFT ADVISORY LEVEL
CONDITIONS ARE POSSIBLE IN OFFSHORE GEORGIA WATERS FRIDAY MORNING
BEFORE A COLD FRONT SHIFTS OFFSHORE. ELSEWHERE...WINDS SHOULD PEAK
BETWEEN 15 TO 20 KTS BEYOND 10 NM FROM THE COASTLINE. SEAS WILL ALSO
BUILD UP TO TO 3 TO 5 FT AHEAD OF THE FRONT. BY SATURDAY...A
NORTH/NORTHEAST WIND WILL BE IN PLACE AS HIGH PRESSURE TRIES TO
WEDGE SOUTHWARD BEHIND THE STALLING COLD FRONT. HOWEVER...LOW
PRESSURE IS EXPECTED TO DEVELOP WELL INLAND ON SUNDAY...RESULTING IN
EAST/SOUTHEAST WINDS EARLY NEXT WEEK. WINDS SHOULD PEAK AS HIGH AS
15 TO 20 KTS ON SUNDAY...AND COULD REMAIN ENHANCED THROUGH MONDAY AS
A COLD FRONT PUSHES OFFSHORE LATE. HIGH PRESSURE WILL THEN BUILD
OVER THE WATERS ON THROUGH THE MIDDLE OF NEXT WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/DPB
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1259 AM EDT THU MAR 24 2016
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND OVER THE REGION INTO THURSDAY. A COLD
FRONT WILL MOVE SLOWLY THROUGH THE AREA ON FRIDAY...LIKELY STALLING
JUST SOUTH AND EAST OF THE REGION THROUGH THE WEEKEND. UNSETTLED
WEATHER WILL BE POSSIBLE THROUGH THE WEEKEND...ESPECIALLY SUNDAY. A
COLD FRONT IS EXPECTED TO PUSH THROUGH THE AREA MONDAY...THEN HIGH
PRESSURE BUILDS FROM THE NORTH ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MADE MINOR ADJUSTMENTS TO OVERNIGHT LOWS AND HOURLY TEMPERATURES
PER GOING TRENDS. ANY SHOWER ACTIVITY THAT DEVELOPS OFF THE LOWER
SOUTH CAROLINA COAST SHOULD REMAIN OFFSHORE...ALTHOUGH AN ISOLATED
SHOWER OR TWO COULD APPROACH THE CHARLESTON COUNTY COAST BY
SUNRISE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
MODELS CONTINUE TO EXHIBIT A FAIR AMOUNT OF UNCERTAINTY LATER IN
THIS PERIOD. THE SETUP LOOKS SIMILAR TO LAST WEEKEND...WHEN THE
MODELS PREDICTED WET/HIGH POPS...BUT NOT MUCH OCCURRED. TRYING TO
SETTLE ON POPS AND PRECIP TIMING WAS VERY DIFFICULT. THEREFORE MADE
GENERALLY ONLY MINOR CHANGES TO THE PREVIOUS FORECAST FOR THIS
PERIOD.
THURSDAY...THIS WILL BE THE BEST WEATHER DAY OF THE PERIOD AS HIGH
PRESSURE CONTINUES TO RETREAT EASTWARD INTO THE ATLANTIC. LOW LEVEL
FLOW BECOMES SOUTHERLY...WHICH WILL HELP KEEP TEMPERATURES COOLER
NEAR THE COAST. NOT BUYING THE NAM...WHICH KEEPS TRYING TO BRING IN
PRECIP OFF OF THE ATLANTIC DURING THE DAY. KEPT SLIGHT CHANCE POPS
OVER THE WATERS AND GRADUAL INCREASE OF POPS FROM WEST TO EAST
DURING THE DAY. LATEST MODEL CONSENSUS SEEMS TO BE A LITTLE SLOWER
WITH BRINGING MOISTURE/PRECIP CHANCES BACK IN WITH THE APPROACHING
FRONT FROM THE WEST. THUS...HAVE MAINTAINED PREVIOUS FORECAST OF
HOLDING OFF MEASURABLE POPS THROUGH THE DAY. HIGH TEMPERATURES WILL
BE ABOVE NORMAL IN THE UPPER 70S TO AROUND 80.
THURSDAY NIGHT THROUGH FRIDAY...THE FRONT MOVES SLOWLY THROUGH THE
AREA DURING THIS PERIOD AND SEEMS TO STALL JUST OFFSHORE BY LATE
FRIDAY. BEST DEEP LAYER MOISTURE AND WEAK FORCING EXISTS DURING THIS
PERIOD. HAVE KEPT 30-50% POPS FOR THIS PERIOD...BUT CONFIDENCE IS
NOT VERY HIGH AS GUIDANCE HAS BEEN WAFFLING BACK AND FORTH ON POPS
FOR THIS PERIOD. STILL FEEL CHANCES FOR ANY SEVERE WEATHER IS VERY
LOW GIVEN LACK OF STRONG FORCING AND INSTABILITY. HOWEVER...THERE IS
ABUNDANT BULK SHEAR OF 30-50 KTS...WHICH COULD PRODUCE GUSTY WINDS
WITH ANY STRONGER SHOWERS OR ISOLATED THUNDERSTORMS. LOW
TEMPERATURES IN THE LOWER 60S THURSDAY NIGHT AND HIGHS IN THE MID
70S FRIDAY UNDER MOSTLY CLOUDY SKIES.
FRIDAY NIGHT...LATEST MODELS INDICATE THAT THERE MAYBE A BIT OF A
LULL IN PRECIP CHANCES...BUT AGAIN CONFIDENCE NOT VERY HIGH. HAVE
GONE WITH LOW END CHANCES CLOSER TO THE COAST AND THEN CHANCE OVER
THE ATLANTIC WATERS...AND SLIGHT CHANCE FURTHER INLAND. LOWS IN THE
MID TO UPPER 50S WITH MOSTLY CLOUDY/CLOUDY CONDITIONS.
SATURDAY...GLOBAL MODELS SHOW ANOTHER WAVE OF LOW PRESSURE MOVING
BACK TOWARD THE AREA FROM THE SOUTHWEST ALONG THE FRONT TO THE
SOUTH. BEST MOISTURE AND POTENTIAL FORCING APPEARS TO BE MAINLY OVER
THE SOUTHERN HALF OF THE AREA...WHICH IS WHERE WE KEPT LOW END
CHANCE POPS. HIGHS GENERALLY IN THE LOWER TO MID 70S...BUT WILL ALSO
DEPEND ON SKY COVER. EXPECT MOSTLY CLOUDY OVER THE SOUTH AND PARTLY
TO MOSTLY CLOUDY NORTH.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
TRENDS FAVOR A WETTER PATTERN OVER THE SOUTHEASTERN UNITED STATES
LATE WEEKEND INTO EARLY NEXT WEEK AS H5 SHORTWAVES PASS OVER A WEAK
WARM FRONT TRYING TO LIFT NORTH INTO THE AREA. SHOWER AND
THUNDERSTORM COVERAGE SHOULD BE GREATEST SUNDAY NIGHT INTO MONDAY
WHEN DEEP MOISTURE CHARACTERIZED BY PWATS BETWEEN 1.50 TO 1.75
INCHES ADVECTS TO THE REGION AHEAD OF A COLD FRONT APPROACHING FROM
THE WEST. EXPECT PRECIP ACTIVITY TO COME TO AN END AS THE COLD FRONT
PUSHES THROUGH THE AREA LATE MONDAY NIGHT INTO TUESDAY. DRY AND
SLIGHTLY COOLER HIGH PRESSURE WILL THEN FOLLOW THROUGH THE MIDDLE OF
NEXT WEEK.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
VFR. LOW-LEVEL JET HAS SHOWN SIGNS OF WEAKENING OVER THE PAST 1-2
HOURS WITH THE LATEST RAP PROGS SHOWING LOW-LEVEL WIND SHEAR
CRITERIA DIMINISHING BY 06Z. WILL DROP MENTION FROM BOTH KCHS AND
KSAV WITH THE 06Z TAF CYCLE. SHALLOW GROUND FOG IS POSSIBLE JUST
BEFORE SUNRISE AT BOTH TERMINALS...BUT NO IMPACTS ARE ANTICIPATED.
COULD SEE A FEW SHOWERS NEAR THE KCHS TERMINAL LATER THIS MORNING
AS A NORTH- SOUTH ORIENTED MOISTURE CHANNEL SETS UP JUST OFF THE
LOWER SOUTH CAROLINA COAST. ANY ACTIVITY SHOULD REMAIN EAST OF THE
TERMINAL.
EXTENDED AVIATION OUTLOOK...THURSDAY NIGHT THROUGH
SUNDAY...PERIODS OF FLIGHT RESTRICTIONS POSSIBLE...ESPECIALLY
THURSDAY NIGHT THROUGH FRIDAY WITH SHOWERS AND ISOLATED
THUNDERSTORMS. THERE MAY BE A BREAK WITH PRECIP CHANCES FOR FRIDAY
NIGHT...BUT LOW CLOUDS MAY STILL BE AN ISSUE. BEST CHANCES FOR
FLIGHT RESTRICTIONS WILL BE OVER KSAV SATURDAY AND SUNDAY AS LOW
PRESSURE POTENTIALLY CROSSES SOUTH OF THE AREA. MONDAY AND
TUESDAY...A RETURN TO VFR CONDITIONS AS A COLD FRONT LIKELY PUSHES
THROUGH THE AREA ON MONDAY WITH HIGH PRESSURE MONDAY NIGHT AND
TUESDAY.
&&
.MARINE...
OVERNIGHT...ON THE PERIPHERY OF ATLANTIC HIGH PRESSURE S/SE WINDS
10-15 KNOTS WILL VEER SLIGHTLY TOWARD THE S/SW LATER TONIGHT.
SEAS WILL RANGE FROM 1-2 FT NEARSHORE WATERS TO 2-3 FT BEYOND 20
NM.
THURSDAY...NO HIGHLIGHTS EXPECTED AS HIGH PRESSURE CONTINUES TO MOVE
EAST OF THE AREA WITH SOUTHERLY WINDS OF 15 KTS OR LESS AND SEAS 4
FT OR LESS.
THURSDAY NIGHT AND FRIDAY...MODELS STILL INDICATING THE POTENTIAL
FOR MARGINAL SCA CONDITIONS AHEAD OF A SLOWLY APPROACHING COLD FRONT
FROM THE WEST...ESPECIALLY THROUGH EARLY FRIDAY. GIVEN IT IS IN THE
THIRD AND FOURTH PERIOD OF THE FORECAST AND THERE IS STILL SOME
UNCERTAINTY...HAVE OPTED TO HOLD RAISING AN SCA FOR THIS PERIOD.
FRIDAY NIGHT THROUGH SUNDAY...NO HIGHLIGHTS EXPECTED. A COLD FRONT
STALLS JUST SOUTH AND EAST OF THE WATERS. WEAK WAVES OF LOW PRESSURE
POTENTIALLY MOVE ALONG THIS FRONT TO PRODUCE PERIODS OF SHOWERS AND
ISOLATED THUNDERSTORMS. WINDS GENERALLY SOUTHWEST AT 15 KTS OR LESS
AND SEAS 4 FT OR LESS...EXCEPT NORTH-NORTHEAST WINDS POSSIBLE NORTH
WATERS...DEPENDING ON WHERE SURFACE FRONT ENDS UP.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
356 AM CDT THU MAR 24 2016
.SHORT TERM...
354 AM CDT
TODAY AND TONIGHT...
STRONG SPRING STORM SYSTEM WORKING ITS WAY THROUGH THE MIDWEST
THIS MORNING. WATER VAPOR IMAGERY INDICATES THE MAIN MID-LEVEL
CIRCULATION WAS CENTERED NEAR KANSAS CITY AT 08Z...WITH A 998 MB
SURFACE LOW JUST NORTHEAST OF KMCI AND A STATIONARY FRONT
EXTENDING NORTHEASTWARD ACROSS NORTHERN IL AND INTO FAR NORTHWEST
INDIANA JUST SOUTH OF LAKE MICHIGAN. 08Z SURFACE OBS DEPICT A 26
DEGREE DIFFERENCE IN TEMPS ACROSS THE CWA...FROM 35 AT WAUKEGAN TO
61 AT RENSSELAER INDIANA. THIS WILL CONTINUE TO BE THE CASE TODAY
AS THE SURFACE LOW TRACKS ALONG THE FRONT...AND EVENTUALLY MOVES
EAST OF THE AREA LATE THIS AFTERNOON.
WFO LOT CWA IS CURRENTLY IN A LULL BETWEEN BAND OF SHOWERS AND
THUNDERSTORMS WHICH LIFTED ACROSS THE AREA OVER THE PAST SEVERAL
HOURS. AREA OF RAIN/EMBEDDED THUNDER OVER EASTERN MISSOURI AND
WEST CENTRAL IL IS EXPECTED TO SPREAD NORTHEAST BACK INTO THE AREA
THIS MORNING HOWEVER...AS DEEP FORCING INCREASES AHEAD OF
APPROACHING UPPER TROUGH AND STRONG MOISTURE TRANSPORT CONTINUES
PARTICULARLY INTO THE SOUTHEASTERN HALF OF THE FORECAST AREA. DRY
SLOT THEN PUSHES IN FROM THE SOUTHWEST MIDDAY/AFTERNOON WHICH
SHOULD CURTAIL PRECIP ACROSS THE SOUTH/SOUTHEAST...WHILE THE
TRAILING PORTION OF THE SYSTEM DEFORMATION ZONE PASSES ACROSS
NORTHERN ILLINOIS. FORECAST SOUNDINGS AND THICKNESS FIELDS
INDICATE THE COLUMN WILL COOL ENOUGH TO CHANGE LINGERING
DEFORMATION BAND PRECIP OVER TO SOME WET SNOW BEFORE ENDING EARLY
THIS EVENING...WITH A BRIEF PERIOD OF MIXED RAIN/SNOW/SLEET DURING
THE TRANSITION. GUIDANCE IS FAIRLY BULLISH WITH POTENTIAL FOR
ACCUMULATING SNOW ACROSS NORTH CENTRAL IL DURING THE LATE
AFTERNOON...AND WHILE SOME ACCUMULATION IS LIKELY...3-4 INCHES
INDICATED BY VARIOUS WRF RUNS MAY BE OVERDONE. EVEN SO...IT DOES
APPEAR THAT SOME ACCUMULATION CAN BE EXPECTED ACROSS FAR NORTH
CENTRAL AND NORTHERN IL WITH PERHAPS AN INCH ON GRASSY OR ELEVATED
SURFACES. PRECIP THEN WINDS DOWN QUICKLY THIS EVENING AS THE
SYSTEM DEPARTS TO THE EAST.
TEMPS TODAY ARE NOT EXPECTED TO STRAY TOO FAR FROM WHERE THEY ARE
NOW WITH THE FRONT BISECTING THE FORECAST AREA. SOME NORTHWARD
MOVEMENT OF THE BOUNDARY IS POSSIBLE ESPECIALLY SOUTH/SOUTHEAST OF
THE CHICAGO METRO AREA...THOUGH CONFIDENCE IS FAIRLY LOW ON EXACT
PLACEMENT. COLDER AIR SURGES IN THIS EVENING ON BLUSTERY NORTH
WINDS AS SKIES CLEAR OUT LATE.
RATZER
&&
.LONG TERM...
354 AM CDT
SATURDAY NIGHT THROUGH THURSDAY...
FRIDAY THROUGH WEDNESDAY...
NICE WEATHER EXPECTED FRIDAY AS UPPER TROUGH FROM OUR CURRENT
MID-WEEK STORM SYSTEM LIFTS AWAY TO THE NORTHEAST AND LOW
AMPLITUDE SHORT WAVE RIDGE DEVELOPS OVERHEAD. SURFACE HIGH
PRESSURE DRIFTS EAST ACROSS THE CWA DURING THE DAY...WITH
SUBSIDENCE AND DRY COLUMN EXPECTED TO PRODUCE A GOOD DEAL OF
SUNSHINE. LIGHT WINDS IN THE VICINITY OF THE RIDGE AXIS THROUGH
EARLY AFTERNOON SHOULD ALLOW FOR TYPICAL SPRING LAKE BREEZE
DEVELOPMENT...THOUGH 925-950 MB MODEL THERMAL FIELDS INDICATE
INLAND AREAS SHOULD BE ABLE TO REACH HIGHS IN THE 48-52 DEGREE
RANGE. WINDS TURN SOUTHEAST BY EVENING...SETTING UP A SEASONABLY
COOL NIGHT AS MID AND HIGH CLOUDS EVENTUALLY INCREASE FROM THE
WEST AHEAD OF THE NEXT UPSTREAM DISTURBANCE.
THAT DISTURBANCE IS ACTUALLY A COUPLE OF INDIVIDUAL SHORT WAVES
WHICH HELP TO AMPLIFY A BROAD UPPER TROUGH ACROSS THE CENTRAL
CONUS THROUGH THE WEEKEND...ONE MOVING ACROSS THE UPPER
MISSISSIPPI VALLEY SATURDAY WHILE THE OTHER DIGS ACROSS THE
CENTRAL/SOUTHERN PLAINS AND EVENTUALLY INDUCES A DEEPENING AREA OF
LOW PRESSURE OVER THE OHIO VALLEY AND LOWER GREAT LAKES REGION BY
LATE SUNDAY AS IT BEGINS TO SWING NORTHEAST FROM THE BASE OF THE
TROUGH. MODEST HEIGHT FALLS DEVELOP INTO THE AREA SATURDAY MORNING
WITH THE APPROACH OF THE NORTHERN WAVE...THOUGH LOW LEVEL MOISTURE
RETURN IS LIMITED TO A NARROW CORRIDOR AHEAD OF THE COLD FRONT
WHICH TRAILS THE SURFACE LOW PRESSURE REFLECTION OVER WISCONSIN.
THUS PRECIP POTENTIAL DURING THE DAY SATURDAY LOOKS TO BE FOCUSED
ACROSS THE WESTERN HALF OF THE CWA AND PRIMARILY MIDDAY INTO THE
AFTERNOON WITH THE ADVANCING COLD FRONT. DESPITE INCREASING MID-
HIGH CLOUD COVER...SOUTH WINDS SHOULD HELP WARM TEMPS INTO THE 50S
OVER MUCH OF THE AREA AND TO AROUND 60 ACROSS THE SOUTH.
WRF...WHICH IS SLOWER WITH THE FRONT...INDICATES A BIT OF A
SOUTHEAST COMPONENT ALONG THE IL LAKESHORE WHICH MAY INDICATE A
VERY WEAK LAKE BREEZE.
FRONT PUSHES EAST ACROSS THE AREA SATURDAY EVENING...THOUGH
LATEST MODEL RUNS REALLY SCALE BACK PRECIP DURING THE EVENING AS
THE STRONGER SYNOPTIC FORCING BECOMES SPLIT TO OUR NORTH AND WELL
TO THE SOUTH. AS THE SOUTHERN LOW BEGINS TO DEVELOP AND DEEPEN
LATE SATURDAY NIGHT...FRONTOGENETIC FORCING ALONG THE SOUTH END OF
THE FRONT INCREASES AND ALLOWS RAIN TO DEVELOP FROM THE SOUTHWEST
INTO PARTS OF THE CWA BY SUNDAY MORNING. MEDIUM-RANGE GUIDANCE
REMAINS A LITTLE DIFFERENT WITH THE EXACT LOW TRACK ACROSS THE
MIDWEST SUNDAY/SUNDAY NIGHT...THOUGH GENERALLY FOCUS PRECIP ACROSS
THE SOUTHEAST HALF TO TWO THIRDS OF THE FORECAST AREA. PARTIAL
THICKNESS FIELDS INDICATE NEARLY ALL OF THE PRECIP WOULD FALL AS
RAIN...THOUGH THE SLIGHTLY FARTHER NORTHWEST TRACK OF THE 12Z
ECMWF WOULD SUPPORT A BRIEF MIX OR CHANGEOVER TO WET SNOW LATE
SUNDAY NIGHT OR EARLY MONDAY BEFORE PRECIP ENDS. CURRENT MODEL
PROGS GENERATE SOME SUBSTANTIAL QPF TOTALS ACROSS THE SOUTHEAST
PORTION OF THE FORECAST AREA THROUGH SUNDAY NIGHT...FROM 0.50
INCHES IN THE FARTHER SOUTHEAST GFS TO 1.25 INCHES IN THE ECMWF.
RISING HEIGHTS THEN DEVELOP INTO THE AREA MONDAY AS THE UPPER
TROUGH PULLS AWAY TO THE EAST...WITH GOOD MODEL CONSENSUS IN
DEVELOPING BROAD UPPER RIDGE ACROSS THE AREA THROUGH MID-WEEK
BEFORE THE NEXT AMPLIFIED UPPER TROUGH APPROACHES. SURFACE HIGH
PRESSURE OVER THE AREA MONDAY INTO TUESDAY WILL LIKELY SUPPORT
LAKE BREEZES BOTH DAYS...WITH TEMPS MODERATING FROM THE MID-40S TO
MID 50S EAST TO WEST MONDAY AND TO THE 55-60 RANGE ON TUESDAY.
SURFACE LOW DEVELOPING TO THE WEST OF THE AREA BY WEDNESDAY WOULD
SUPPORT CONTINUED SOUTH FLOW AND MILD TEMPS MID-WEEK...THOUGH WITH
AN INCREASING CHANCE OF RAIN.
RATZER
&&
.AVIATION...
FOR THE 06Z TAFS...
A LINE OF THUNDERSTORMS IS RACING EAST ACROSS THE MISSISSIPPI RIVER
LATE THIS EVENING AND IS PROGGED TO MOVE ACROSS THE NORTHERN
ILLINOIS AND NORTHWEST INDIANA TERMINALS A LITTLE BEFORE 07Z FOR RFD
AND ROUGHLY 730-9Z FOR THE CHICAGO AREA TERMINALS. BEHIND THIS LINE
OF THUNDERSTORMS...MID LEVEL DRY SLOT WILL PUNCH OVERHEAD AND SHOULD
ALLOW PRECIP TO DIMINISH TO A DRIZZLE FOR A FEW HOURS BEFORE STEADY
RAIN SPREADS BACK IN LATE TONIGHT THROUGH THE MORNING MONDAY.
FRONTAL BOUNDARY AT 05Z STRETCHES FROM NEAR PNT NNE TO NEAR VPZ AND
IS PROGGED LIFT NORTH INTO CHICAGO LATE TONIGHT INTO EARLY THURSDAY.
WINDS SHOULD LIGHTEN UP A BIT AS THE FRONTAL TROUGH NEARS. LOOKS
LIKE ORD IS A GOOD BET TO STAY NORTH OF THE FRONT WITH NORTHEAST
WINDS WHILE EXPECT GYY TO HAVE FROPA WITH WINDS TURNING SOUTHERLY.
IT WILL BE VERY CLOSE TO MDW BETWEEN ROUGHLY 08-12Z BEFORE THE
BOUNDARY STARTS TO MOVE SOUTH AGAIN. THIS MEANS A HIGH DEGREE OF
UNCERTAINTY IN WIND DIRECTION FOR MDW...THOUGH WOULD EXPECT SPEEDS
TO BE LESS THAN 10 KT.
LOW PRESSURE WILL PASS NEAR OR SOUTH OF THE TERMINALS MIDDAY
THURSDAY WITH WINDS BACKING TO THE NORTH AND EVENTUALLY NORTHWEST
LATE AFTERNOON INTO THE EVENING. COOLER AIR WILL WORK INTO THE
REGION BEHIND THE LOW WITH PRECIP TYPE BECOMING MORE OF A CONCERN AS
THE DAY WEARS ON. RFD HAS THE BEST CHANCE TO SEE SOME LIGHT
ACCUMULATIONS FROM MID AFTERNOON INTO EARLY EVENING BEFORE DRIER AIR
FINALLY ARRIVES. FOR THE CHICAGO AREA...THERMAL PROFILES ARE MORE
MARGINAL AND MAY ONLY SEE A RAIN/SNOW MIX BEFORE DRIER AIR MOVES IN
AND WE LOSE ICE CRYSTALS IN THE COLUMN.
BMD
&&
.MARINE...
315 AM CDT
MODERATELY STRONG NORTHEASTERLY WINDS OF 30 TO 35 KT ARE IN PLACE
OVER MUCH OF LAKE MICHIGAN EARLY THIS MORNING AHEAD OF AN AREA
OF LOW PRESSURE OVER NORTHERN MISSOURI. WEAKER FLOW IS IN PLACE
ACROSS THE FAR SOUTHERN END OF LAKE MICHIGAN WHERE A FRONTAL
TROUGH IS IN PLACE. THE LOW WILL MOVE JUST SOUTH OF LAKE MICHIGAN
THIS AFTERNOON WITH WINDS BACKING TO THE NORTH AND GALES SPREADING
SOUTH ACROSS THE REMAINDER OF THE LAKE. GALES SHOULD DIMINISH
TONIGHT AND WINDS WILL BECOME LIGHT ON FRIDAY AS A RIDGE AXIS
MOVES OVER THE LAKE. FRESH SOUTHERLY FLOW RESUMES LATE FRIDAY INTO
SATURDAY AS THE RIDGE DEPARTS TO THE EAST ANOTHER FRONT MOVES
ACROSS LAKE MICHIGAN SATURDAY NIGHT INTO SUNDAY TURNING WINDS
NORTH AGAIN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS
UNTIL 4 PM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...4 PM THURSDAY TO 4 AM FRIDAY.
&&
$$
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
[top]
Area Forecast Discussion
National Weather Service Lincoln IL
323 AM CDT THU MAR 24 2016
.SHORT TERM...(Today and tonight)
ISSUED AT 323 AM CDT Thu Mar 24 2016
08z/3am surface analysis shows 997mb low over northern Missouri,
with stationary frontal boundary extending into north-central
Illinois. Based on latest obs, it appears the boundary extends from
near Macomb to just north of Pontiac. To the south of the front in
the warm sector, much of the KILX CWA has current temps in the lower
60s. Meanwhile to the north of the boundary, readings are only in
the lower 40s in Galesburg. A broken line of convection associated
with the approaching low developed across eastern Kansas/western
Missouri last evening...however that activity diminished as it
tracked northeastward and skirted the NW CWA around midnight. Latest
radar imagery shows very little going on across central Illinois:
however, showers are beginning to develop upstream and should spread
into the area over the next couple of hours. HRRR has been quite
persistent showing the showers becoming more widespread along/west
of I-55 after 09z/4am. As the low and accompanying cold front get
closer, showers and a few thunderstorms will develop across the
entire area early this morning. Have therefore carried categorical
PoPs across the board. The low will track to near the Chicago area
by midday, pulling the cold front through central Illinois and
pushing the widespread rain into Indiana at that time. Have
therefore lowered PoPs to just low chance across most of the area
this afternoon. The exception will be northwest of the Illinois
River, where deformation zone rain and snow showers will persist
through the afternoon. High temperatures will be achieved early in
the day, with readings falling steadily this afternoon. By mid
afternoon, temps will range from the upper 30s northwest of the
Illinois River...to the middle 50s near the Indiana border.
&&
.LONG TERM...(Friday through Wednesday)
ISSUED AT 323 AM CDT Thu Mar 24 2016
As low pressure continues to lift into the eastern Great Lakes, a
few rain/snow showers may linger along/north of the I-74 corridor
early this evening before coming to an end before midnight. Skies
will initially be overcast, but will clear from west to east
overnight with lows dropping into the upper 20s and lower 30s. High
pressure will build into the region on Friday, leading to mostly
sunny and cool conditions with highs in the lower to middle 50s.
Once the high shifts off to the east, the next system will begin to
approach from the west over the weekend. Models have been
struggling with this feature for the past several days, and
agreement remains poor with the 00z Mar 24 run. The main issues
have been how much and how quickly an approaching short-wave trough
will amplify. Given the progressive flow pattern, have generally
preferred the weaker and faster solution. As such, will continue to
feature highest rain chances Sunday/Sunday night...followed by a
return to dry weather for Monday and Tuesday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1140 PM CDT Wed Mar 23 2016
Frontal boundary has remained stationary from just south of PIA
to just north of BMI this evening. Winds at PIA remained E, with S
winds at the remaining terminals. As low pressure continues to
approach from the west, winds will eventually shift veer to SW by
mid-day and then become W-NW from late afternoon near PIA to mid-
evening at CMI.
A line of storms approaching Knox county appears to be tracking to
the NW of Peoria. Showers are on track to affect the PIA airport
between 0530z and 07z before lifting off to the northeast. After
that, the HRRR and RAP models point toward the development of a
line of showers and storms along the Illinois River Valley around
10z/5am. The line is expected to expand eastward, then with the
back edge of rain lingering near the IL river until the low
pressure center reaches PIA around 17z and progresses into Indiana
by 20z. A trough of low pressure trailing behind the low along
I-74 will be the focus for light rain showers through the
afternoon for the northern terminals of PIA and BMI. The other
terminals will see precip come to an end from west to east between
19z at SPI to 21z at CMI. If any precip continues near PIA to BMI
until 00z/7pm, light snow could develop. However, no snow
accumulation is expected.
The aviation conditions will dip from VFR to MVFR as precipitation
develops, then remain MVFR possibly until the end of the taf
period. The southern terminals will have the better potential of
seeing cigs improve to VFR during the afternoon as the dry slot
punches across SPI/DEC/CMI. Then, wrap around moisture and a
subsidence inversion could produce MVFR clouds again at all TAF
sites after sunset tomorrow evening.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1212 AM CDT THU MAR 24 2016
.UPDATE...
949 PM CDT
MAIN CHANGES TO EVENING/OVERNIGHT FORECAST WAS TO TWEAK
TEMPERATURE AND WIND TRENDS BASED ON OBSERVATIONS OF QUASI-
STATIONARY FRONT POSITION...WHICH WAS LOCATED IN A MEANDERING
FASHION FROM JUST SOUTH OF PNT TO IKK TO SOUTH OF VPA TO JUST
NORTH OF OXI AS OF 0200 UTC. AS SURFACE LOW TRACKS NORTHEAST
OVERNIGHT INTO EARLY THURSDAY...PRESSURE FALLS WILL ENABLE FRONT
TO LIFT SLOWLY NORTH AS WARM FRONT TOWARD I-80 CORRIDOR...THOUGH
WILL MAKE BETTER NORTHWARD PROGRESS WITH EASTWARD EXTENT IN CWA.
STEEPER LAPSE RATES/COOLING ALOFT ASSOCIATED WITH IMPRESSIVE
CLOSED LOW ON W/V IMAGERY SHOULD ENABLE CAPPING IN PLACE TO
DIMINISH...WITH SLIGHT TO CHANCE THUNDER MENTION
MAINTAINED...BETTER CHANCE SOUTH OF THE FRONT. THERE HAS BEEN A
SLOW DOWNWARD TREND IN LIGHTNING COVERAGE OFF TO THE WEST.
THUS...REGARDING STRONG/SEVERE PROSPECTS OVERNIGHT/EARLY
THURSDAY...CANNOT COMPLETELY RULE IT OUT IN FAR SOUTHWEST
CWA. HOWEVER...IT APPEARS BETTER CHANCE FOR AN ISOLATED STRONG TO
SEVERE STORM WILL BE SOUTHWEST OF THE CWA WHERE SLIGHTLY HIGHER
INSTABILITY WILL RESIDE.
THERE HAS NOT BEEN MUCH IN WAY OF SIGNIFICANT VISIBILITY
REDUCTIONS THIS EVENING NORTH OF FRONT...BUT WITH LOW DEWPOINT
SPREADS MAINTAINED PATCHY FOG MENTION. BETTER POTENTIAL FOR AREAS
OF FOG...EVEN LOCALLY DENSE...COULD OCCUR JUST NORTH OF FRONT AND
CLOSER TO LAKE MICHIGAN IN PREDAWN HOURS THROUGH MID MORNING.
INCREASED FOG COVERAGE TO AREAS OF FOG IN GRIDS FOR THAT AREA.
FINALLY...REGARDING ACCUMULATING SNOW POTENTIAL ON THURSDAY
AFTERNOON...DID NOT MAKE BIG CHANGES TO GRIDS...BUT CONTINUE TO
BE CONCERNED FOR A PERIOD OF HEAVY SNOW RIGHT AFTER CHANGEOVER FOR
PARTS OF FAR NORTHERN ILLINOIS ALONG THE 700 MB DEFORMATION AXIS
PATH. ALONG WITH THE ROCKFORD AREA...THIS COULD INCLUDE NORTHERN
PORTIONS OF THE CHICAGO METRO AREA DURING THE AFTERNOON COMMUTE.
LATEST 00Z NAM IS ROUGHLY IN LINE WITH 18Z GFS IN THIS
SCENARIO...SO WILL NEED TO CLOSELY MONITOR OBSERVATIONAL TRENDS.
THINK THAT THE WINDOW WILL BE BRIEF AND PLACEMENT OF THE BAND
COULD VARY...BUT WITHIN IT...AMOUNTS OF 1"+ IN A SHORT TIME COULD
OCCUR/ESPECIALLY ON COLDER SURFACES. IF BAND PLACEMENT VERIFIES
CLOSE TO NAM/GFS...CANNOT RULE OUT LOCAL AMOUNTS UP TO 2-3". WILL
BRIEF MIDNIGHT SHIFT ON THESE CONCERNS.
RC
&&
.SHORT TERM...
331 PM CDT
THROUGH FRIDAY...
A SURFACE FRONTAL BOUNDARY REMAINS NEARLY STATIONARY OVER MY
SOUTHERN COUNTIES THIS AFTERNOON...WITH A SHARP CONTRAST IN
TEMPERATURES ON EITHER SIDE OF IT. TO THE NORTH...MAINLY 40S TO LOW
50S ARE PROMINENT...WITH THE EXCEPTION OF NEAR LAKE MICHIGAN WHERE
TEMPERATURES HAVE BEEN NEAR 40. SOUTH OF THE FRONT...TEMPERATURES
ARE IN THE LOW TO MID 60S. PRECIPITATION THROUGH THE DAY HAS BEEN
MAINLY TO OUR NORTH OF WISCONSIN...WHERE A BAND OF FRONTOGENESIS HAS
BEEN THE PRIMARILY DRIVER. HOWEVER...RADAR IMAGERY OVER THE PAST HOUR
HAS SHOWN AN UPTICK IN MAINLY VERY LIGHT RAIN OR DRIZZLE OVER
NORTHWESTERN ILLINOIS. THIS APPEARS TO BE THE MAIN STORY OVER THE
AREA THIS EVENING...WITH ONLY SOME LIGHT SHOWERS OR DRIZZLE
IMPACTING THE AREA.
SHOWERS...AND EVEN SOME THUNDERSTORM CHANCES SHOULD INCREASE FROM
WEST TO EAST OVER THE AREA OVERNIGHT INTO EARLY THURSDAY MORNING AS
THE MAIN STORM SYSTEM...NOW OVER THE KANSAS...SHIFTS TOWARDS
NORTHERN ILLINOIS. AS THIS LOW APPROACHES OVERNIGHT...THE SURFACE
FRONT WILL LIKELY SHIFT NORTHWARD UP NEAR THE I80 CORRIDOR BY
DAYBREAK THURSDAY. AS A RESULT...TEMPERATURES WILL LIKELY COME UP A
FEW DEGREES OVERNIGHT WHERE THE WARM FRONT PASSES. THE BEST CHANCE
OF THUNDERSTORMS LOOKS TO COME LATER TONIGHT INTO THURSDAY. THERE
ALSO CONTINUES TO BE A THREAT OF A FEW STRONG...TO POSSIBLY
MARGINALLY SEVERE STORMS OVER SOUTHERN PORTIONS OF THE AREA (MAINLY
SOUTH OF I-80) LATE TONIGHT THROUGH EARLY THURSDAY AFTERNOON.
OVERALL INSTABILITY WILL NOT BE OVERLY IMPRESSIVE...BUT THE
COMBINATION OF STRONG DEEP LAYER SHEAR AND THE DYNAMIC FORCING WITH
THE STORM SYSTEM COULD STILL SUPPORT A FEW STRONG STORMS AHEAD OF
THE COLD FRONT.
FARTHER TO THE NORTH...MAINLY OVER NORTHWESTERN AND PORTIONS OF FAR
NORTH CENTRAL ILLINOIS...THINGS COULD GET INTERESTING THURSDAY
AFTERNOON AS IT APPEARS A GOOD MID-LEVEL DEFORMATION ZONE MAY SET UP
OVER THIS AREA ALONG AND NEAR THE PATH OF THE 700 MB LOW. THIS COULD
SUPPORT A BAND OF MODERATE TO HEAVY WET SNOW OVER PORTIONS OF
NORTHWESTERN AND NORTH CENTRAL ILLINOIS...ESPECIALLY BY MID TO LATE
THURSDAY AFTERNOON. GIVEN THE POTENTIAL OF A BAND OF STRONG FGEN
SETTING UP WITHIN THIS DEFORMATION ZONE...ALONG WITH THE FACT THAT
LOOKS TO COINCIDE WITH THE PERIOD OF BEST MID-UPPER LEVEL Q-VECTOR
CONVERGENCE...ASSOCIATED WITH THE STRONG MID-LEVEL WAVE...THIS COULD
SET UP A PERIOD OF HEAVY SNOW. WE CAN ALSO NOT TOTALLY RULE OUT THE
POSSIBILITY OF CONVECTIVE SNOW RATES...ESPECIALLY CONSIDERING ALL OF
THE LIGHTNING AND REPORTS OF TSSN OVER WESTERN NEBRASKA OVER THE
PAST FEW HOURS. IN SPITE OF THIS POTENTIAL FOR SNOW...POSSIBLY
IMPACTING AREAS IN AND AROUND THE ROCKFORD AREA THURSDAY
AFTERNOON...UNCERTAINTY ON IMPACTS REMAIN LOW AT THIS TIME. THIS IS
DUE TO THE FACT THAT THESE BANDS OF HEAVY SNOW TEND TO BE
NARROW...AND GIVEN THAT GROUND TEMPS HAVE BEEN WARM LATELY IT WILL
TAKE HEAVY SNOW RATES IN ORDER TO GET ACCUMULATIONS...AND THIS MAY
END UP ONLY OCCURRING ON GRASSY AREAS AND ELEVATED SURFACES...WHERE
A COUPLE INCHES OF WET SNOW IS CERTAINLY POSSIBLE. THEREFORE...AT
THIS TIME I WILL MENTION THE POTENTIAL OF SOME HEAVY SNOW IN THE
HWO.
SOME SNOW COULD GET INTO THE CHICAGO AREA BY EARLY THURSDAY EVENING
BEFORE ENDING...BUT IT APPEARS UNLIKELY THAT ANY REAL ACCUMULATIONS
WOULD MATERIALIZE OUTSIDE OF NORTH CENTRAL ILLINOIS.
KJB
&&
.LONG TERM...
153 PM CDT
SATURDAY NIGHT THROUGH WEDNESDAY...
SATURDAY NIGHT THROUGH SUNDAY NIGHT...LOW PRESSURE CURRENTLY IN THE
GULF OF ALASKA WILL BE MOVING OUT OF THE SOUTHERN ROCKIES INTO THE
CENTRAL PLAINS ON SATURDAY NIGHT. A PORTION OF THE ENERGY WITH THIS
LOW WILL BE ABSORBED INTO THE NORTHERN STREAM UPPER LEVEL FLOW
PATTERN. THIS INTRODUCES CONSIDERABLE UNCERTAINTY INTO THE FORECAST
FOR SUNDAY INTO EARLY MONDAY AS FAR AS THE STRENGTH OF THE SURFACE
LOW THAT WILL DEVELOP...AND HOW PROGRESSIVE THE PATTERN WILL BE.
APPEARS THERE WILL BE SEMI-DECENT CHANCES FOR RAIN WITH THE LEAD
WAVE SATURDAY NIGHT...AND MODELS ARE IN PRETTY GOOD AGREEMENT ON
THIS. THE DIFFERENCES APPEAR MORE SO SUNDAY AS THE ECMWF IN ITS PAST
FEW RUNS DEVELOPS A STRONGER SURFACE LOW...AND THUS A MORE
SIGNIFICANT DEFORMATION BAND OF PRECIPITATION SUNDAY/SUNDAY NIGHT
WHEREAS THE GFS HAS A MORE PROGRESSIVE OPEN WAVE AND JUST SOME LIGHT
RAIN IF ANYTHING. THE GEM IS SOMEWHERE IN THE MIDDLE AND CLOSER TO
THE MORE FAVORED GUIDANCE FROM THE NATIONAL CENTERS...BUT ENSEMBLE
GUIDANCE STILL EXHIBITS QUITE A BIT OF SPREAD. THIS MIDDLE ROAD
SUGGESTS A DECENT BAND OF RAIN SUNDAY THEN SHIFTING EAST SUNDAY
NIGHT. WILL CONTINUE WITH THE MODEL BLEND WHICH GIVES HIGH END
CHANCE OF RAIN...WHICH COULD CERTAINLY BE HIGHER IF THE SLOWER
SOLUTIONS PREVAIL.
MONDAY... WEAK HIGH PRESSURE RETURNS FOR MONDAY RESULTING IN A
SEAONABLY COOL BUT DRY DAY WITH MORE SUNSHINE.
TUESDAY INTO MIDWEEK...ANOTHER DEEP UPPER TROUGH WILL BUILD ACROSS
THE WESTERN CONTINENTAL UNITED STATES. EXPECT SOME WARMING ON
TUESDAY CLOSER TO NORMS IN THE LOWER 50S...BUT WITH LOW PRESSURE
DEVELOPING TO OUR WEST ONSHORE WINDS WILL KEEP AREAS CLOSER TO THE
LAKE A BIT COLDER THAN NORMAL. THE UPPER LEVEL TROUGH WILL MOVE
EASTWARD INCREASING CHANCES FOR MILD AND WETTER WEATHER LATER IN THE
WEEK.
KMD
&&
.AVIATION...
FOR THE 06Z TAFS...
A LINE OF THUNDERSTORMS IS RACING EAST ACROSS THE MISSISSIPPI RIVER
LATE THIS EVENING AND IS PROGGED TO MOVE ACROSS THE NORTHERN
ILLINOIS AND NORTHWEST INDIANA TERMINALS A LITTLE BEFORE 07Z FOR RFD
AND ROUGHLY 730-9Z FOR THE CHICAGO AREA TERMINALS. BEHIND THIS LINE
OF THUNDERSTORMS...MID LEVEL DRY SLOT WILL PUNCH OVERHEAD AND SHOULD
ALLOW PRECIP TO DIMINISH TO A DRIZZLE FOR A FEW HOURS BEFORE STEADY
RAIN SPREADS BACK IN LATE TONIGHT THROUGH THE MORNING MONDAY.
FRONTAL BOUNDARY AT 05Z STRETCHES FROM NEAR PNT NNE TO NEAR VPZ AND
IS PROGGED LIFT NORTH INTO CHICAGO LATE TONIGHT INTO EARLY THURSDAY.
WINDS SHOULD LIGHTEN UP A BIT AS THE FRONTAL TROUGH NEARS. LOOKS
LIKE ORD IS A GOOD BET TO STAY NORTH OF THE FRONT WITH NORTHEAST
WINDS WHILE EXPECT GYY TO HAVE FROPA WITH WINDS TURNING SOUTHERLY.
IT WILL BE VERY CLOSE TO MDW BETWEEN ROUGHTLY 08-12Z BEFORE THE
BOUNDARY STARTS TO MOVE SOUTH AGAIN. THIS MEANS A HIGH DEGREE OF
UNCERTAINTY IN WIND DIRECTION FOR MDW...THOUGH WOULD EXPECT SPEEDS
TO BE LESS THAN 10 KT.
LOW PRESSURE WILL PASS NEAR OR SOUTH OF THE TERMINALS MIDDAY
THURSDAY WITH WINDS BACKING TO THE NORTH AND EVENTUALLY NORTHWEST
LATE AFTERNOON INTO THE EVENING. COOLER AIR WILL WORK INTO THE
REGION BEHIND THE LOW WITH PRECIP TYPE BECOMING MORE OF A CONCERN AS
THE DAY WEARS ON. RFD HAS THE BEST CHANCE TO SEE SOME LIGHT
ACCUMULATIONS FROM MID AFTERNOON INTO EARLY EVENING BEFORE DRIER AIR
FINALLY ARRIVES. FOR THE CHICAGO AREA...THERMAL PROFILES ARE MORE
MARGINAL AND MAY ONLY SEE A RAIN/SNOW MIX BEFORE DRIER AIR MOVES IN
AND WE LOSE ICE CRYSTALS IN THE COLUMN.
BMD
&&
.MARINE...
258 PM CDT
FRONTAL BOUNDARY DRAPED JUST SOUTH OF LAKE MICHIGAN WILL ALLOW FOR
CONTINUED BRISK NORTHEAST WINDS WHICH ALLOW FOR HIGHER WAVE ACTION
ON THE WEST HALF OF THE LAKE THROUGH TONIGHT. GALES
CONTINUE IN THE NORTHEAST REGIME FOR THE NORTHERN
MAJORITY OF THE LAKE TONIGHT. PRECIPITATION TRENDS
WILL BE ON THE INCREASE TONIGHT AS LOW PRESSURE NEARS FROM THE
SOUTHWEST. A SLIGHT INCREASE IN THE PRESSURE GRADIENT FOR THE
SOUTHERN THIRD OF THE LAKE WILL ALLOW WINDS TO INCREASE TO GALE
FORCE THURSDAY AFTERNOON. BY FRIDAY MORNING WINDS WILL RELAX AND
BECOME NORTHWEST...TRANSITIONING TO SOUTH AS HIGH PRESSURE NUDGES
IN.
MM
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ741 UNTIL 4 AM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...4 PM THURSDAY TO 4 AM FRIDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 PM THURSDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1140 PM CDT WED MAR 23 2016
.UPDATE...
Issued at 905 PM CDT Wed Mar 23 2016
The frontal boundary is extending across our northern counties,
has stalled out along a line from just south of Peoria to just
north of Bloomington. Steady northeast winds north of the front
are keeping cooler conditions there in the upper 40s, with
southerly winds south of the boundary keeping temps in the 60s.
Radar returns in east-central Illinois may be producing a few
sprinkles, but no measurable rain is expected from that band as it
mainly works to saturate the lower levels. Low pressure is still
expected to track east along the warm front, reaching near
Schuyler county around 15z/10am tomorrow. Then the low will
quickly track east across our northern counties and into Indiana
by 18z/1pm. The low will drag a cold front across our forecast
area in the process, with storms affecting our east-southeast
counties later Thursday morning into early afternoon, or mainly SE
of Effingham to Paris.
Instability params show some hail and wind potential with the
initial wave of storms that will reach Knox county around
05z/midnight, and clip northern Peoria county as well as Stark and
Marshall counties. Then the best instability looks to redevelop in
our E-SE counties Thur morning, but only marginal chances of
severe wind and hail are expected in that area as well.
Updates this evening were mainly to the weather grids to delay the
onset of rain and storms this evening, with better chances coming
after midnight. Temps are on track, with little change or diurnal
swings expected. Thus, a very mild night is in store south of the
front.
Updated forecast info is already available.
&&
.SHORT TERM...(Tonight)
ISSUED AT 258 PM CDT Wed Mar 23 2016
Frontal boundary position has not changed much since this morning,
with 2 pm analysis showing it extending from just north of Macomb,
to the northern Peoria metro area, to just south of Kankakee. Still
seeing temperatures only around 50 degrees at Galesburg, while the
Peoria airport (south side of metro) is 61 degrees. Further south,
mid-upper 60s were more widespread, with some 70 degree readings
toward Jacksonville. Radar mosaics show precipitation with this
system well off to our north.
The boundary extends southwest to a low pressure area in north
central Kansas. The low will slowly ride northeast along it, and
should nudge the front back north with time later tonight. HRRR
projecting convective development near the Missouri/Kansas border by
late afternoon, tracking it northeast to west central Illinois by
midnight. High-res models such as the ARW and NMM bring the line
into the central Illinois area after midnight. Best chances of any
strong/severe storms would basically be from I-55 west, where the
RAP model focuses MUCAPE values up to 1000 J/kg, but the incoming
line should get more disorganized with time so am not expecting a
widespread severe threat. Latest Day1 outlook has the entire
forecast area in a marginal risk of severe weather. More showers and
storms will surge northeast after midnight ahead of the incoming
cold front, with the highest PoP`s for eastern Illinois associated
with this surge.
Little in the way of temperature movement expected overnight, with
upper 50s to lower 60s prevailing much of the time. Biggest question
mark remains with the far north, depending on the position of the
front.
.LONG TERM...(Thursday through Wednesday)
ISSUED AT 258 PM CDT Wed Mar 23 2016
12Z forecast models generally bring 991 mb low pressure over
north central KS to track along a frontal boundary into northeast IL
by midday Thu as it weakens to 995-998 mb and swing a cold front
east across IL roughly between 15Z-21Z. High chances of showers and
a few thunderstorms early Thu morning to gradually diminish chances
from west to east during afternoon behind cold front. A new line of
convection to develop ahead of cold front during Thu afternoon and
SPC has marginal risk of severe near the Wabash river valley Thu
afternoon for hail and gusty winds, though best chances of stronger
storms will be further east of IN. Not much temp rise Thu with
breezy conditions again and may even slip behind the cold frontal
passage, with highs ranging from 50-55F nw of IL river to 60-65F
over eastern IL. Snow chances still appears to be north of CWA on
Thu and only have slight chances of light rain/snow showers Thu
evening over east central IL with no accumulations.
Low pressure moves into the eastern Great Lakes region overnight Thu
night and winds to gradually diminish as weak high pressure of 1020
mb settles east into the MS river valley by dawn Friday. Low clouds
to decrease from west to east overnight Thu night and set up another
night of freezing temps over central and nw IL. Lows 27-32F with
areas se of I-70 32-34F. Southern 6 counties where growing season
has begun, may need a freezing warning especially if clouds and
winds diminish quicker overnight Thu night. Weak high pressure
drifts east over IL Fri morning and into Ohio by sunset Friday,
providing a mostly sunny day with lighter winds, and highs mostly in
the lower 50s. So a similar day on Friday that we experienced this
past Monday.
A short wave trof off the Canadian Pacific coast will dive southeast
and deepen an upper level trof into the Rockies and great plains
this Easter Weekend. This ejects another fairly strong low pressure
ne from north Texas at sunset Saturday into central or southeast IL
on Easter Sunday. 12Z models still have some timing differences
along with placement of low pressure track and will stay close to
consensus. Have chances of showers into areas form I-55 west by
Saturday afternoon as clouds increase, with milder highs in the
upper 50s/lower 60s. Shower chances then spreading east over rest of
CWA Sat night, except still dry in far southeast IL near Wabash
river until Sunday. Depending on track of low pressure, southeast IL
may see a few thunderstorms on Easter Sunday. Highs Sunday range
from lower 50s nw of IL river, to 60-65F in southeast IL. Shower
chances to diminish from west to east overnight Sunday night and may
linger isolated showers near Wabash river Monday morning. High
pressure ridge already moving into IL by Monday afternoon to
decrease clouds on Monday with seasonable highs in the mid 50s.
Upper level ridging into the MS river valley on Tue and ohio river
valley next Wed to bring quiet weather with temps moderating to 55-
60F on Tue and into the 60s next Wed. Next chance of showers and
possible thunderstorms to arrive middle of next week on Wed night
and Thu as low pressure tracks into the upper MS river valley.
&&
.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1140 PM CDT Wed Mar 23 2016
Frontal boundary has remained stationary from just south of PIA
to just north of BMI this evening. Winds at PIA remained E, with S
winds at the remaining terminals. As low pressure continues to
approach from the west, winds will eventually shift veer to SW by
mid-day and then become W-NW from late afternoon near PIA to mid-
evening at CMI.
A line of storms approaching Knox county appears to be tracking to
the NW of Peoria. Showers are on track to affect the PIA airport
between 0530z and 07z before lifting off to the northeast. After
that, the HRRR and RAP models point toward the development of a
line of showers and storms along the Illinois River Valley around
10z/5am. The line is expected to expand eastward, then with the
back edge of rain lingering near the IL river until the low
pressure center reaches PIA around 17z and progresses into Indiana
by 20z. A trough of low pressure trailing behind the low along
I-74 will be the focus for light rain showers through the
afternoon for the northern terminals of PIA and BMI. The other
terminals will see precip come to an end from west to east between
19z at SPI to 21z at CMI. If any precip continues near PIA to BMI
until 00z/7pm, light snow could develop. However, no snow
accumulation is expected.
The aviation conditions will dip from VFR to MVFR as precipitation
develops, then remain MVFR possibly until the end of the taf
period. The southern terminals will have the better potential of
seeing cigs improve to VFR during the afternoon as the dry slot
punches across SPI/DEC/CMI. Then, wrap around moisture and a
subsidence inversion could produce MVFR clouds again at all TAF
sites after sunset tomorrow evening.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...Shimon
SHORT TERM...Geelhart
LONG TERM...07
AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
427 AM EDT THU MAR 24 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 240900Z KIND TAF UPDATE/...
ISSUED AT 427 AM EDT THU MAR 24 2016
SOME SHOWER ACTIVITY STARTING TO DEVELOP OVER SOUTHWEST INDIANA MAY
IMPACT THE KIND TERMINAL AFTER ABOUT 241000Z...BUT APPEARS THESE SHOWERS
WILL BE RATHER LIGHT WITH LITTLE TO NO VISIBILITY RESTRICTION. SHORT
TERM MODEL GUIDANCE SUGGEST BETTER LIFT/MORE WIDESPREAD RAINFALL MORE
TOWARDS THE LATE MORNING HOURS.
WILL ALSO PUSH BACK THE TIMING OF THE LOWER MVFR CEILINGS MORE TOWARDS THE
EXPECTED ARRIVAL OF THE WIDESPREAD PRECIPITATION.
PREVIOUS DISCUSSION FOLLOWS.
GOOD CONFIDENCE THAT VFR CONDITIONS WILL DETERIORATE TO MVFR SHORTLY
AFTER ISSUANCE TIME WITH INCREASING SHOWER COVERAGE AS UPPER WAVES
MOVE NORTHEAST OVER THE AREA AHEAD OF A STRONG SYSTEM NORTHWEST OF
KANSAS CITY.
SCATTERED SHOWERS WERE OVER THE LAF AND HUF AREAS LATE THIS EVENING
AND SHOULD CONTINUE TO INCREASE IN COVERAGE AND SPREAD SOUTHEAST
OVERNIGHT. WILL START OFF WITH VCSH AND VFR CEILINGS AND THEN MVFR
IN LIGHT SHOWERS 07Z-09Z. SHOWERS COULD BE MODERATE OR POSSIBLY EVEN
HEAVY AT TIMES WITH BRIEF IFR. COULD ALSO SEE SOME EMBEDDED THUNDER
AFTER 10Z...BUT CONFIDENCE IS TOO LOW TO MENTION. THE ASSOCIATED
COLD FRONT SHOULD MOVE TO NEAR LAF AND HUF 18Z-20Z AND 21Z-23Z AT
IND. AFTER THAT...COVERAGE OF POST-FRONTAL SHOWERS AND ISOLATED
STORMS EXPECTED TO BE TOO SPARSE TO MENTION AND FLYING CONDITIONS
LIKELY TO IMPROVE TO VFR.
SOUTH WINDS TO 10 KNOTS OR MORE WILL CONTINUE OVERNIGHT WITH GUSTS
TO NEAR 20 KNOTS. WINDS WILL PICK UP AGAIN AFTER 15Z AND START OFF
FROM THE SOUTH 15-18 KNOTS WITH GUSTS TO 25 KNOTS. THE WIND WILL
VEER TO THE SOUTHWEST...WEST AND FINALLY NORTHWEST IN THE WAKE OF
THE COLD FRONT. IT WILL REMAIN BREEZY AFTER SUNSET WITH SUSTAINED
WINDS TO 15 KNOTS AND GUSTS TO 20 KNOTS OR MORE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...MK/JAS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
359 AM EDT THU MAR 24 2016
.SYNOPSIS...
ISSUED AT 342 AM EDT THU MAR 24 2016
AN UPPER LEVEL DISTURBANCE ACROSS THE CENTRAL UNITED STATES WILL
APPROACH THE AREA TODAY. THIS DISTURBANCE WILL INTERACT WITH A
FRONTAL BOUNDARY ACROSS THE AREA TO PRODUCE WIDESPREAD RAIN
SHOWERS ALONG WITH A FEW THUNDERSTORMS THROUGH THIS AFTERNOON.
GUSTY SOUTH WINDS ARE EXPECTED IN ADVANCE OF THE COLD FRONT WITH
THIS SYSTEM...PARTICULARLY ACROSS FAR NORTHEAST INDIANA AND
NORTHWEST OHIO TODAY. SCATTERED RAIN SHOWERS MAY LINGER INTO THIS
EVENING...BUT DRIER AND COOLER AIR MOVING INTO THE REGION BEHIND A
COLD FRONT WILL GRADUALLY END THE CHANCES OF ADDITIONAL RAIN
SHOWERS OVERNIGHT. CLOUDS WILL DIMINISH ON FRIDAY WITH COOLER
TEMPERATURES. HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE
MID 50S ACROSS NORTHWEST INDIANA AND FAR SOUTHWEST LOWER
MICHIGAN...TO THE MID 60S ACROSS NORTHWEST OHIO. LOW TEMPERATURES
TONIGHT WILL DROP INTO THE LOWER TO MID 30S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM EDT THU MAR 24 2016
STALLED SURFACE BOUNDARY REMAINS SPRAWLED FROM FAR NORTHERN INDIANA
INTO FAR NORTHWEST OHIO THIS MORNING. BROAD ISENTROPIC LIFT/MOISTURE
ADVECTION CONTINUES IN ASSOCIATION WITH THIS BOUNDARY AND HAS
LARGELY BEEN RESPONSIBLE FOR WIDESPREAD RAIN SHOWERS/DRIZZLE ACROSS
PRIMARILY NORTHERN HALF OF THE FORECAST AREA DURING THE OVERNIGHT
HOURS. EXPECTING THAT SOME DIMINISHMENT IN RAIN SHOWER COVERAGE WILL
OCCUR ACROSS THE NORTH DURING THE EARLY-MID MORNING HOURS AS MORE
FAVORED ZONE OF ISENTROPIC ASCENT PER 295K-300K LAYER PROGS LIFTS
NORTHWARD ACROSS CENTRAL LOWER MICHIGAN. RAIN POTENTIAL TO RAMP
UP FROM WEST TO EAST FROM MID MORNING THROUGH THE AFTERNOON AS
POTENT PV ANOMALY OVERSPREADS MID MS VALLEY/SOUTHERN GREAT LAKES
ALONG WITH A CORRESPONDING DOWNSTREAM LOW/MID LEVEL FGEN RESPONSE.
SOME WEAK ELEVATED INSTABILITY IS NOTED PER SPC RUC ANALYSIS AT
06Z ACROSS THE FAR NORTH...BUT PRIMARY INSTABILITY AXIS OF NOTE
FOR LOCAL AREA WILL BE IMMEDIATELY PRECEDING SFC COLD FRONTAL
BOUNDARY THIS AFTERNOON WITH SOME DIFFERENTIAL THERMAL ADVECTION
SETTING UP THIS NARROW CORRIDOR OF INSTABILITY. MAGNITUDE OF
INSTABILITY IS EXPECTING TO BE ON THE MARGINAL SIDE...GENERALLY IN
THE 500-800 J/KG RANGE...BUT A BRIEF POTENTIAL OF NEAR SFC/SFC
BASED INSTABILITY MAY EXIST ACROSS SOUTHEAST HALF OF THE AREA LATE
MORNING-LATE AFTERNOON. THIS WEAK INSTABILITY COMBINED WITH FAIRLY
IMPRESSIVE DEEP LAYER SHEAR MAGNITUDES OF 50-60 KNOTS DOES POSE
SOME CONCERN FOR SMALL LINEAR BOWING SEGMENTS. THIS THREAT REMAINS
HIGHLY CONDITIONAL ON INSTABILITY AND OVERALL SEVERE THREAT
REMAINS LOW. NOT MUCH CHANGE FROM PREVIOUS FORECAST THINKING WITH
ISOLD SEVERE POTENTIAL AT BEST TODAY GIVEN LIMITED
INSTABILITY...WITH ISOLATED STRONGER WIND GUSTS AS THE MAIN
THREAT.
TEMPERATURE FORECAST REMAINS A CHALLENGING ONE IN THE NEAR
TERM...WITH A 20 DEGREE NORTH TO SOUTH TEMPERATURE DIFFERENTIAL
ACROSS THE FORECAST AREA THIS MORNING. SFC BOUNDARY HAS REMAINED
SOMEWHAT STUBBORNLY ANCHORED ACROSS FAR NORTHERN INDIANA...BUT
SHOULD START TO SEE SOME NORTHWARD RETREAT OF THIS BOUNDARY IN THE
09Z-15Z TIMEFRAME. THIS SHOULD PUT BULK OF FORECAST AREA IN WARM
SECTOR...ALBEIT FOR A VERY BRIEF TIME ACROSS THE FAR NORTHWEST AS
SFC REFLECTION REACHES NORTHWEST INDIANA LATE MORNING. OVERALL NOT
MUCH CHANGE TO INHERITED MAX TEMPS...WITH JUST A SLIGHT UPWARD
ADJUSTMENTS INTO THE MID 60S FAR SOUTH CENTRAL/EAST WHERE RESIDENCE
TIME OF WARM SECTOR WILL BE PROLONGED...AND WHERE A MORE DELAYED
PRECIP TIMING IS ANTICIPATED. ANOTHER LOWER END CONCERN TODAY WILL
BE A BRIEF POTENTIAL OF NEAR ADVISORY OR ADVISORY LEVEL SOUTH-
SOUTHWEST WINDS AHEAD OF THIS SYSTEM. SFC REFLECTION SHOULD BE IN A
SLIGHT DEEPENING MODE THIS AFTERNOON WITH AN AXIS OF FAIRLY
STRONG SFC PRESSURE FALLS EXPECTED TO DEVELOP/MIGRATE ACROSS
SOUTHEAST LOWER MICHIGAN. THESE PRESSURE FALLS COMBINED WITH
POTENTIALLY BETTER MIXING WHERE SFC TEMPS ARE EXPECTED TO REACH
THE MID 60S...COULD ALLOW FOR A BRIEF WINDOW OF 35 TO 45 MPH WIND
GUSTS ACROSS THE FAR EAST IN THE 16Z-21Z TIMEFRAME GIVEN STRONG
LOW LEVEL WIND FIELD. HAVE HELD OFF ON ANY WIND ADVISORY AT THIS
TIME GIVEN LOW CONFIDENCE ON DEPTH OF MIXING AND RELATIVELY SHORT
DURATION OF THIS POTENTIAL.
DRY SLOT TO OVERSPREAD THE AREA TONIGHT AS COLDER AIR ADVECTS
SOUTHEASTWARD BEHIND THE FRONT DIMINISHING PRECIP COVERAGE IN THE
EVENING...ALTHOUGH DEFORMATION ZONE MAY PROLONG AT LEAST SCATTERED
SHOWERS ACROSS THE FAR NORTHWEST. ANY CHANGEOVER TO SNOW SHOULD BE
OF MINIMAL PRECIP COVERAGE/INTENSITY AND NO SNOW ACCUMULATION IS
ANTICIPATED AT THIS TIME. END OF THIS PRECIP EVENT COULD TURN OUT
TO BE MORE DRIZZLY IN NATURE TONIGHT...BUT CURRENTLY NOT EXPECTING
ANY SIGNIFICANT IMPACTS FROM POTENTIAL DRIZZLE OR FREEZING DRIZZLE
TONIGHT.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 342 AM EDT THU MAR 24 2016
MUCH MORE BENIGN WEATHER ANTICIPATED FOR FRIDAY AND SATURDAY. ANY
RESIDUAL RN/SN SHOWERS WILL BE QUICKLY CUT OFF BY 12Z AS SHORTWAVE
RIDGE AND ASSOCIATED BUBBLE OF SUBSIDENCE/SURFACE HIGH PRESSURE FOLD
INTO THE GREAT LAKES. SHOULD BE MOSTLY SUNNY BY AFTERNOON AS
NEGATIVE THETA-E ADVECTION FINALLY ERODES THIN LAYER OF MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION IN CAA REGIME. HIGH TEMPS WILL
MAKE A RUN AT UPPER 40S BY LATE AFTERNOON AS WINDS START TO BACK.
LOW 50S MAY EVEN BE POSSIBLE IF MORNING CLOUDS DISSIPATE QUICKER
THAN EXPECTED. MUCH WARMER CONDITIONS FOR SATURDAY AS SW FLOW/WAA
RAMP UP AHEAD OF NEXT WAVE. UPPER 50S TO NEAR 60F POSSIBLE GIVEN
850MB TEMPS AROUND 4C...BUT THE TRADEOFF WILL BE INCREASING HIGH-
BASED CLOUDS ESPECIALLY IN OUR NORTHWEST BY AFTERNOON AS MIDLEVEL
WARM/MOIST AIR ADVECTION INCREASES.
NEXT CHANCE OF RAIN WILL ARRIVE EARLY SUNDAY MORNING AS ANOTHER
VIGOROUS SHORTWAVE RIPPLES THROUGH THE REGION. STILL SOME
INCONSISTENCIES AMONG THE LATEST DETERMINISTIC GUIDANCE TO WORK OUT.
HOWEVER DOES APPEAR TO BE SOME CONSENSUS FOR SURFACE WAVE
DEVELOPMENT ALONG BAROCLINIC ZONE WITH DECENT SHOT OF SOME MODERATE
RAIN AS MIDLEVEL TROUGH TAKES ON AT LEAST A NEUTRAL TILT. BEST
PRECIP CHANCES LOOK TO BE SUNDAY AFTERNOON INTO SUNDAY NIGHT.
THERMAL PROFILES SHOULD BE WARM ENOUGH FOR ALL RAIN...THOUGH IT IS
WORTH NOTING THE ECMWF SOLUTION WOULD SUPPORT THE POSSIBILITY OF A
FEW WET SNOWFLAKES MIXING IN ON BACK EDGE OF EXITING DEFORMATION
BAND. STILL PLENTY OF TIME TO WATCH THIS EVENT AND SUSPECT THERE
WILL BE CHANGES SINCE PARENT JET ENERGY IS STILL OVER THE NORTH
PACIFIC. QUIET WEATHER THEREAFTER AS SPRAWLING MID/UPPER RIDGE AND
SURFACE HIGH MOVE OVER THE REGION. COOL AT FIRST BUT SHOULD WARM UP
AGAIN BY MIDWEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 113 AM EDT THU MAR 24 2016
FRONTAL BOUNDARY REMAINS ANCHORED APPROXIMATELY ALONG THE ROUTE 6
CORRIDOR EARLY THIS MORNING. AN INTENSIFYING LOW LEVEL JET
CUTTING ACROSS THIS BOUNDARY HAS ALLOWED FOR RENEWED POSITIVE
THETAE ADVECTION AND EXPANDING AREA OF LIGHT RAIN/DRIZZLE ACROSS
MUCH OF NORTHERN INDIANA. DURING THE REMAINDER OF THE EARLY
MORNING HOURS...SFC FRONTAL BOUNDARY IS EXPECTED TO CREEP
NORTHWARD ALONG WITH A NORTHWARD SHIFT TO STRONGEST ISENTROPIC
UPGLIDE. THESE TRENDS SHOULD TEND TO DIMINISH RAIN COVERAGE TOWARD
DAYBREAK FOR A BRIEF TIME. IN THE MEANWHILE...IFR/LIFR CONDITIONS
WILL REMAIN LIKELY ALONG AND TO THE NORTH OF THIS BOUNDARY AT
KSBN OVER NEXT SEVERAL HOURS...WITH SOME IMPROVEMENT TO MAINLY IFR
EXPECTED AFTER 09Z OR 10Z. FOCUS FOR THE REMAINDER OF THE FORECAST
WILL BE EASTWARD PROGRESSION OF STRONG VORT MAX ASSOCIATED WITH
UPPER TROUGH AND APPROACHING FRONTAL BOUNDARY. RAIN WILL INCREASE
IN INTENSITY ACROSS NORTHWEST INDIANA AFTER DAYBREAK AND
EVENTUALLY FOR KFWA TOWARD MIDDAY. SOME POTENTIAL OF THUNDER WILL
EXIST AT KFWA AS WEAK INSTABILITY AXIS PRECEDES THE FRONT. HAVE
CARRIED VCTS AT KFWA WITH THE 06Z TAFS MAINLY FROM 18Z-21Z.
OUTSIDE OF SHOWERS WINDS WILL BECOME QUITE GUSTY IN THE WARM
SECTOR...WITH A PERIOD OF SOUTH WIND GUSTS OF 30 TO 35 KNOTS
EXPECTED AT KFWA LATE MORNING/EARLY AFTERNOON. WINDS TO SHIFT
WEST-NORTHWEST BEHIND THE FRONT TONIGHT...WITH GUSTS TO 20 TO 25
KNOTS AND POTENTIAL OF SOME SCATTERED LINGERING RAIN SHOWERS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING FROM 5 PM THIS AFTERNOON TO 5 AM EDT FRIDAY FOR
LMZ043-046.
&&
$$
SYNOPSIS...MARSILI
SHORT TERM...MARSILI
LONG TERM...AGD
AVIATION...MARSILI
VISIT US AT WW.WEATHER.GOV/IWX
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
329 AM EDT THU MAR 24 2016
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 240600Z TAF ISSUANCE/...
ISSUED AT 1145 PM EDT WED MAR 23 2016
GOOD CONFIDENCE THAT VFR CONDITIONS WILL DETERIORATE TO MVFR SHORTLY
AFTER ISSUANCE TIME WITH INCREASING SHOWER COVERAGE AS UPPER WAVES
MOVE NORTHEAST OVER THE AREA AHEAD OF A STRONG SYSTEM NORTHWEST OF
KANSAS CITY.
SCATTERED SHOWERS WERE OVER THE LAF AND HUF AREAS LATE THIS EVENING
AND SHOULD CONTINUE TO INCREASE IN COVERAGE AND SPREAD SOUTHEAST
OVERNIGHT. WILL START OFF WITH VCSH AND VFR CEILINGS AND THEN MVFR
IN LIGHT SHOWERS 07Z-09Z. SHOWERS COULD BE MODERATE OR POSSIBLY EVEN
HEAVY AT TIMES WITH BRIEF IFR. COULD ALSO SEE SOME EMBEDDED THUNDER
AFTER 10Z...BUT CONFIDENCE IS TOO LOW TO MENTION. THE ASSOCIATED
COLD FRONT SHOULD MOVE TO NEAR LAF AND HUF 18Z-20Z AND 21Z-23Z AT
IND. AFTER THAT...COVERAGE OF POST-FRONTAL SHOWERS AND ISOLATED
STORMS EXPECTED TO BE TOO SPARSE TO MENTION AND FLYING CONDITIONS
LIKELY TO IMPROVE TO VFR.
SOUTH WINDS TO 10 KNOTS OR MORE WILL CONTINUE OVERNIGHT WITH GUSTS
TO NEAR 20 KNOTS. WINDS WILL PICK UP AGAIN AFTER 15Z AND START OFF
FROM THE SOUTH 15-18 KNOTS WITH GUSTS TO 25 KNOTS. THE WIND WILL
VEER TO THE SOUTHWEST...WEST AND FINALLY NORTHWEST IN THE WAKE OF
THE COLD FRONT. IT WILL REMAIN BREEZY AFTER SUNSET WITH SUSTAINED
WINDS TO 15 KNOTS AND GUSTS TO 20 KNOTS OR MORE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...MK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
310 AM MDT THU MAR 24 2016
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 309 AM MDT THU MAR 24 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS CLOSED
UPPER LOW CENTERED OVER NORTHEAST KS...WITH SHORTWAVE RIDGING
BUILDING ACROSS THE CENTRAL ROCKIES TOWARD THE NORTHERN PLAINS ON
THE BACK SIDE OF THIS SYSTEM. THERE ARE STILL A FEW WEAK PLUMES OF
DEEPER MOISTURE ROTATING AROUND THE BACK SIDE OF THIS SYSTEM JUST
EAST OF OUR CWA. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS
EASTERN COLORADO WITH STRONG SURFACE LOW PRESSURE ACROSS NORTHERN
MISSOURI. TIGHT SURFACE GRADIENT BETWEEN THESE FEATURES IS STILL IN
PLACE ACROSS THE EASTERN 2/3 OF OUR CWA AND IS SLOWLY RETREATING
EASTWARD.
TODAY-TONIGHT...UPPER LEVEL SHORTWAVE TROUGH TRANSITION ACROSS OUR
CWA WITHIN NW FLOW ALOFT WITH WEAK LEE TROUGH BEGINNING TO REDEVELOP
BY LATE THIS AFTERNOON. DRY CONDITIONS ARE EXPECTED WITH MAIN
FORECAST CHALLENGE BEING IMPACTS OF SNOW PACK ON HIGHS/LOWS. GROUND
TEMPERATURES ARE WARM ENOUGH STILL THAT MELTING SHOULD OCCUR FAIRLY
QUICKLY AFTER SUNRISE. POTENTIAL EXISTS FOR HIGHS TO REACH THE 50S
TODAY...HOWEVER LOCATIONS IN OUR NORTH/NORTHWEST MAY STRUGGLE TO
REACH THE LOW 40S IF SNOW PACK LIMITS DIURNAL HEATING. DEEPEST SNOW
PACK IS IN YUMA COUNTY AND THIS IS WHERE I HAVE LEAST CONFIDENCE IN
HIGHS TODAY. LOWS TONIGHT SHOULD DROP FAIRLY QUICKLY...HOWEVER LEE
TROUGH BEGINS TO DEEPEN AS ANOTHER FRONT APPROACHES THE REGION WITH
INCREASING BL WINDS. I LEANED LOW TEMP FORECAST TOWARDS 2M GUIDANCE
(WARMER BLENDS) AS MIXING MAY PREVENT BETTER RADIATIONAL COOLING.
FRIDAY-SATURDAY NIGHT...THE NEXT UPPER LEVEL TROUGH MOVES INTO THE
PLAINS WITH TWO SPLITS OCCURRING FRIDAY AND A FRONTAL PASSAGE DURING
THE DAY FRIDAY OR FRIDAY NIGHT. CONFIDENCE IS NOT PARTICULARLY HIGH
DUE TO VARIANCES IN HOW MODELS SHOW FRONTAL TIMING AND MOISTURE
RETURN BETWEEN THESE SPLIT SHORTWAVE TROUGHS. WHERE PRECIP OCCURS IT
APPEARS THAT TEMP/MOISTURE PROFILES SHOULD SUPPORT MAINLY A SNOW
EVENT. BEST CHANCE FOR PRECIP APPEARS TO BE WHEN THE SOUTHERN
SHORTWAVE ROTATES TROUGH THE PLAINS (LIKELY CENTERED SOUTH OF OUR
FORECAST AREA).
00Z NAM WAS THE STRONGEST ON THIS FEATURE WITH A CLOSED H7 CENTER
PASSING NEAR OUR CWA...HOWEVER 06Z TRACK IS FURTHER SOUTH AND
SLIGHTLY MORE PROGRESSIVE. LATEST ECMWF SHOWS THE H7 LOW CLOSING
OFF FURTHER SOUTHEAST AND DEEPENING OVER EASTERN KS...AND THE GFS
ONLY SHOWS A WEAK OPEN WAVE AT H5/H7. QUITE A BIT OF
VARIANCE...WHICH LOWERS CONFIDENCE IN POTENTIAL IMPACTS.
STRONGEST OVERLAPPING PRECIP SIGNAL IS IN OUR SOUTHERN CWA LATE
FRIDAY NIGHT THROUGH SATURDAY MORNING REGARDLESS OF WHICH MODEL WE
CHOOSE...SO I KEPT CHANCE POPS IN THIS AREA. CONSENSUS FAVORS SNOW
ACCUMULATIONS GENERALLY 1-2" (ASSUMING MAINLY SNOW DURING THE
EVENT). WILL NEED TO CONTINUE MONITORING TRENDS.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 309 AM MDT THU MAR 24 2016
SUNDAY THROUGH TUESDAY WILL BE DRY WITH WARMING TEMPERATURES AS AN
UPPER RIDGE MOVES OVER THE CENTRAL HIGH PLAINS. SURFACE HIGH
PRESSURE MOVES INTO THE SOUTHERN PLAINS AS A LEE TROUGH BEGINS TO
DEEPEN ALONG THE FRONT RANGE MONDAY NIGHT AHEAD OF THE NEXT MAIN
UPPER LOW THAT MOVES INTO THE CENTRAL NEVADA. HIGH TEMPERATURES IN
THE 50S ON SUNDAY WILL WARM INTO THE 70S BY TUESDAY. THE INITIAL
SHORT WAVE TROUGH LIFTS OUT OF THE UPPER LOW ACROSS NORTHEAST
COLORADO AND INTO WESTERN NORTH DAKOTA AND WESTERN NEBRASKA BY MID
DAY WEDNESDAY ALONG WITH A COINCIDENT SURFACE LOW CENTER. THERE IS A
POSSIBILITY OF SHOWERS AND THUNDERSTORMS DEVELOPING OVER THE FAR
EASTERN SECTIONS OF THE FORECAST AREA TUESDAY EVENING INTO EARLY
WEDNESDAY AHEAD OF THE SURFACE THROUGH THAT MOVES EASTWARD.
FROM WEDNESDAY THROUGH THURSDAY MODELS BECOME MORE DIVERGENT ON HOW
THE COMBINATION OF THE UPPER LOW OVER THE WEST AND THE LOW LIFTING
INTO THE NORTHERN PLAINS IS HANDLED. THE GFS TENDS TO SEPARATE
THESE FEATURES MORE WITH THE LOW LIFTING INTO THE NORTHERN PLAINS
MAKING BETTER PROGRESS TOWARDS THE GREAT LAKES REGION THAN THE ECMWF
THAT TENDS TO KEEP THE FEATURES LINKED INTO A SINGLE ELONGATED
TROUGH THAT EXTENDS FROM THE NORTHERN HIGH PLAINS TO OFF THE COAST
OF SOUTHERN CALIFORNIA. EITHER WAY IT APPEARS TEMPERATURES WILL
COOL ACROSS THE CENTRAL HIGH PLAINS REGION WEDNESDAY AND THURSDAY AS
THERE WILL BE A COLD FRONT THAT MOVES ACROSS THE REGION WEDNESDAY
NIGHT WITH A CHANCE OF LIGHT RAIN SHOWERS SPREADING ACROSS THE AREA
...CHANGING TO LIGHT SNOW WEDNESDAY NIGHT...AND BACK TO RAIN ON
THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1056 PM MDT WED MAR 23 2016
SNOW WILL CONTINUE TO WIND DOWN DURING THE OVERNIGHT HOURS WITH
IFR TRANSITIONING TO VFR BY 12Z. SURFACE WINDS WILL ALSO GRADUALLY
DIMINISH DURING THAT TIME. THERE COULD BE LINGERING VISIBILITY
RESTRICTIONS DUE TO BLOWING SNOW IN THE 3-5SM RANGE...IMPROVING
THURSDAY MORNING AS WINDS GO LIGHT FROM THE WEST.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...024
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
400 AM EDT THU MAR 24 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 528 PM EDT WED MAR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID LEVEL LOW MOVING OUT
OVER WRN KS IN THE SRN STREAM. TO THE N IN THE NRN STREAM...BROAD
TROFFING COVERS MUCH OF CANADA. IN THE CONFLUENCE BTWN THIS NRN
TROFFING AND RIDGING OUT AHEAD OF THE KS LOW...UPPER JET RUNNING
FROM JUST N OF LAKE SUPERIOR TO NRN NEW ENGLAND IS STRENGTHENING.
INCREASING UPPER DIVERGENCE ASSOCIATED WITH THE RIGHT ENTRANCE OF
THE JET IS AIDING PCPN EXPANSION WELL TO THE N OF A NEARLY
STATIONARY SFC FRONT EXTENDING FROM SFC LOW IN NCNTRL KS TO LAKE
ERIE. CLOSER TO HOME...A FEW STRATOCU DEVELOPED IN NE WIND UPSLOPE
AREAS OFF LAKE SUPERIOR EARLIER TODAY. OTHERWISE...HIGH CLOUDS HAVE
BEEN INCREASING AND THICKENING TODAY AFTER MORNING SUNSHINE.
FCST TONIGHT/THU WILL REVOLVE AROUND EVOLUTION OF WINTER STORM
CURRENTLY OVER THE PLAINS. MODELS ARE IN GOOD AGREEMENT SHOWING THE
MID LEVEL LOW OVER KS GRADUALLY TRANSITIONING TO AN OPEN WAVE AS IT
MOVES INTO THE GREAT LAKES REGION LATE THU. MEANWHILE...ASSOCIATED
SFC LOW PRES WILL TRACK FROM NE KS TO SRN LWR MI THU AFTN. INITIAL
BAND OF SNOW CURRENTLY LIFTING TOWARD UPPER MI IS BEING DRIVEN
LARGELY BY AFOREMENTIONED RIGHT ENTRANCE OF UPPER JET AND RESULTING
STRENGTHENING OF LOW/MID LEVEL FGEN AND ISENTROPIC ASCENT. ALTHOUGH
SNOW IS CURRENTLY DEVELOPING/INTENSIFYING WHILE SLOWLY LIFTING N THRU
WI...IT WILL ENCOUNTER VERY DRY AIR AT THE LOWER LEVELS THAT WILL
CONTINUE TO ADVECT S AND W FROM HIGH PRES OVER ONTARIO. SFC DWPTS
HAVE BEEN DOWN INTO THE SINGLE DIGITS ACROSS PORTIONS OF UPPER MI
THIS AFTN AND ARE IN THE NEGATIVE SINGLE DIGITS IN ONTARIO. WITH ONLY
A SLIGHT NORTHWARD SHIFT OF FGEN/ISENTROPIC ASCENT TONIGHT... THE
APPROACHING SNOW IN WI WILL INCREASINGLY STRUGGLE TO MOVE N INTO
UPPER MI AS ADVECTION OF LOW-LEVEL DRY AIR ERODES THE NRN PORTION OF
THE PCPN SHIELD. ALL AVBL HIGH RES MODEL GUIDANCE...INCLUDING HOURLY
RAP RUNS TODAY AND 18Z NAM...SHOW PCPN HAVING TROUBLE LIFTING MUCH
FARTHER THAN FAR SCNTRL UPPER MI TONIGHT WITH NORTHWARD EXTENT FROM
ROUGHLY JUST N OF IRON MOUNTAIN TO JUST N OF MANSTIQUE BY 12Z THU.
DURING THU MORNING...DEFORMATION SNOW SHIELD...WHICH IS CURRENTLY
PRODUCING CONSIDERABLE LIGHTNING/TSSN ACROSS PORTIONS OF
NEBRASKA...WILL SHIFT INTO THE UPPER GREAT LAKES IN A WEAKENING
STATE. AS THIS OCCURS...SNOW SHOULD EXPAND INTO PORTIONS OF NCTNRL
AND NE UPPER MI. SNOW WILL THEN DIMINISH/END STEADILY FROM W TO E
DURING THE AFTN.
FOR THIS EVENT...DO NOT EXPECT ANY SNOW TO FALL FROM IRONWOOD TO
L`ANSE INTO THE KEWEENAW. IT`S QUESTIONABLE WHETHER ANY SNOW WILL
REACH MARQUETTE. TO THE S AND E...EXPECT A SIGNIFICANT GRADIENT OF
SNOWFALL FROM N TO S WITH WITH AMOUNTS RANGING FROM AROUND 1 INCH
NEAR LAKE SUPERIOR TO ABOUT A FOOT IN THE CITY OF MENOMINEE. THE NRN
EDGE OF THE SNOW WILL BE THE MOST DIFFICULT CHALLENGE AS DRY AIR
CONTNUALLY EATS AWAY AT SNOW LIFTING INTO THE AREA UNDER WEAKENING
FORCING. WOULD NOT BE SURPRISED IF THE NRN EXTENT OF SNOWFALL
REFLECTED IN THIS FCST DOES NOT OCCUR. HAVE ADDED DICKINSON/NRN
SCHOOLCRAFT/LUCE COUNTIES TO ADVY...THOUGH IT WILL ONLY BE THE SRN
PARTS OF THOSE COUNTIES THAT WILL REACH THE LOW SLR ADVY CRITERIA OF
AT LEAST 2-4 INCHES OF SNOW ACCUMULATION. FAR SRN PARTS OF DELTA AND
SCHOOLCRAFT COUNTIES MAY SEE STORM TOTAL SNOW UP AROUND 6 INCHES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 AM EDT THU MAR 24 2016
DRY HI PRES CROSSING THE UPR LKS WL BRING A DRY AND MILDER DAY TO
UPR MI ON FRI. SOME MIXED PCPN...THAT COULD INCLUDE FREEZING RA ON
FRI NGT INTO EARLY SAT...WL RETURN THE FIRST HALF OF THE WEEKEND AS
A LO PRES TROF TRACKS THRU THE CWA. BUT LOOKS LIKE THE BULK OF THIS
PCPN WL FALL AS RA THAT WL TEND TO CHANGE TO SOME SN BEFORE ENDING
EARLY ON SUN AS SOMEWHAT COLDER/DRIER AIR FOLLOWS THE TROF PASSAGE.
THE FIRST COUPLE OF DAYS NEXT WEEK SHOULD THEN BE MAINLY DRY...BUT
ANOTHER CHC OF MAINLY RA WL RETURN MID NEXT WEEK ALONG WITH ABOVE
NORMAL TEMPS.
FRI...A SHRTWV RDG/SFC RDG AXIS WILL SHIFT E THRU THE WRN GREAT LKS.
A SLY FLOW ON THE WRN FLANK OF THE SFC RDG AXIS SHIFTING TO THE E WL
LIFT H85 TEMPS UP TO ABOUT 0C. ALTHOUGH THERE WL BE SOME INCRSG HI
CLDS IN ADVANCE OF A LO PRES TROF APRCHG FM THE W...DAYTIME HEATING
SHOULD LIFT MAX TEMPS WELL INTO THE 40S AWAY FM COOLING OFF THE
GREAT LKS...ESPECIALLY LK MI.
FRI NGT THRU SAT NGT...A LO PRES TROF/COLD FNT ASSOCIATED WITH A
PAIR OF SHRTWVS...ONE IN THE ARCTIC BRANCH FLOW OVER SRN CANADA AND
ANOTHER IN THE POLAR BRANCH FLOW OVER THE CONUS...IS FCST TO DRIFT
SLOWLY ACROSS THE UPR LKS DURING THIS PERIOD. MOST OF THE GUIDANCE
INDICATES PCPN IN ADVANCE OF THE TROF IS FCST TO PUSH INTO THE WRN
CWA BY 06Z SAT WITH INCRSG H85 MSTR ADVECTION LIFTING PWAT UP TO
0.50 INCH INTO THE UPR LKS IN THE SW FLOW AHEAD OF THE TROF AND THEN
OVERSPREAD THE REST OF THE CWA ON SAT. SINCE THE SHRTWVS/DYNAMIC
FORCING WL REMAIN OUT OF PHASE...PCPN AMOUNTS ARE NOT EXPECTED TO BE
HEAVY DESPITE THE RATHER SLUGGISH MOTION OF THE TROF. STILL...MOST
OF THE MODELS GENERATE AT LEAST 0.25 INCH TOTAL PCPN OVER MUCH OF
THE CWA. PCPN SHOULD DIMINISH W-E SAT NGT AND END OVER ALL BUT
PERHAPS THE FAR E BY 12Z SUN FOLLOWING THE PASSAGE OF THE SFC TROF
AND ARRIVAL OF DRYING/DEEP LYR QVECTOR DVGC IN THE WAKE OF PASSING
SHRTWVS. FCST SNDGS/H85-100 THKNS FIELDS SUG THE BULK OF THE PCPN WL
BE MAINLY IN THE FORM OF RA EXCEPT PERHAPS OVER THE WRN CWA. WITH
NOCTURNAL COOLING /ALBEIT LIMITED BY INCRSG CLDS/ AND THE WBLB
EFFECT WITH LINGERING NEAR SFC DRY AIR...FCST SDNGS ALSO HINT AT THE
POTENTIAL FOR SOME FREEZING RA LATE FRI NGT/EARLY SAT MRNG
ESPECIALLY OVER THE INTERIOR CENTRAL...SO ADDED THIS PTYPE INTO THE
FCST. INFLUX OF WARMER AIR/DAYTIME HEATING WL END THIS THREAT BY SAT
AFTN. THE LO PRES TROF/COLD FNT CROSSES THE CWA...PTYPE MAY MIX BACK
WITH MORE SN WITH THE ARRIVAL OF COLDER AIR/DYNAMIC COOLING.
SUN THRU WED...ARRIVAL OF TRAILING SFC RDG AXIS/DRIER AIR BEHIND
DEPARTING LO PRES TROF WL END ANY PCPN THAT MIGHT LINGER OVER THE
ERN CWA ON SUN MRNG. WITH H85 TEMPS ARND -5 TO -7C...EXPECT NEAR
SEASONABLE TEMPS. MEDIUM RANGE GUIDANCE THEN HINTS ANOTHER SHRTWV
EMBEDDED IN THE NW FLOW ALOFT WL IMPACT THE AREA SOMETIME SUN NGT
INTO MON NGT. BUT ANY PCPN IN THE FORM OF SN SHOWERS WITH TEMPS AOB
NORMAL SHOULD BE ON THE LIGHT SIDE GIVEN THE ABSENCE OF ANY MSTR
INFLOW. AS AN UPR RDG/SFC HI PRES BUILDS OVER THE AREA ON TUE...
EXPECT A MOSUNNY DAY. WITH H85 TEMPS FCST TO REBOUND TO ARND 0C...
TEMPS AWAY FM THE COOLING INFLUENCE OF THE LKS SHOULD RISE WELL INTO
THE 40S ON TUE AFTN. AS THE SLY FLOW BTWN THE DEPARTING HI PRES AND
DVLPG LO PRES IN THE PLAINS ADVECTS MOISTER AIR INTO THE UPR LKS ON
WED...SOME PCPN MOST LIKELY IN THE FORM OF RA MAY RETURN BY MID WEEK
ALONG WITH ABOVE NORMAL TEMPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 134 AM EDT THU MAR 24 2016
BEING WELL N OF A WINTER STORM THAT WILL BE TRACKING INTO THE GREAT
LAKES REGION...KIWD/KCMX WILL REMAIN VFR THRU THE FCST PERIOD UNDER
AN E TO NE FEED OF DRY AIR AT THE LOW LEVELS. THE NRN FRINGE OF SNOW
ASSOCIATED WITH THE STORM SYSTEM WILL BRUSH KSAW THU MORNING INTO
THU AFTERNOON. IF SO...VFR CONDITIONS MAY FALL TO MVFR AT THAT TIME.
OTHERWISE...VFR CONDITIONS WILL PREVAIL AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 528 PM EDT WED MAR 23 2016
E TO NE WINDS UP TO 25 TO 30KT ARE EXPECTED TONIGHT INTO THU AS PRES
GRADIENT TIGHTENS OVER THE UPPER LAKES BETWEEN HIGH PRES DRIFTING
ACROSS ONTARIO INTO QUEBEC AND LOW PRES TRACKING FROM THE CENTRAL
PLAINS TO FAR SOUTHERN ONTARIO BY LATE THU EVENING. WINDS WILL
QUICKLY DIMINISH TO 15KT OR LESS FROM W TO E LATE THU AFTN THRU FRI
MORNING AS A HIGH PRES RIDGE ARRIVES. THERE WILL BE SOME INCREASE IN
WINDS LATER FRI INTO SAT AHEAD OF THE NEXT LOW PRES TROF. SOUTHERLY
WINDS OVER THE E HALF OF LAKE SUPERIOR MAY INCREASE INTO THE 15-25KT
RANGE FOR A TIME AHEAD OF THE TROF FRI NIGHT INTO SAT. LIKEWISE...
THERE MAY BE 15-25KT NW WINDS FOR A TIME IN THE WAKE OF THE TROF
PASSAGE LATE SAT/SAT NIGHT. WINDS WILL BECOME LIGHT AGAIN LATER SUN
AS A HIGH PRES RIDGE ARRIVES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR MIZ007-
014-085.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON
FOR MIZ011-013.
WINTER STORM WARNING UNTIL 1 PM CDT THIS AFTERNOON FOR MIZ012.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KC
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
134 AM EDT THU MAR 24 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 528 PM EDT WED MAR 23 2016
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A MID LEVEL LOW MOVING OUT
OVER WRN KS IN THE SRN STREAM. TO THE N IN THE NRN STREAM...BROAD
TROFFING COVERS MUCH OF CANADA. IN THE CONFLUENCE BTWN THIS NRN
TROFFING AND RIDGING OUT AHEAD OF THE KS LOW...UPPER JET RUNNING
FROM JUST N OF LAKE SUPERIOR TO NRN NEW ENGLAND IS STRENGTHENING.
INCREASING UPPER DIVERGENCE ASSOCIATED WITH THE RIGHT ENTRANCE OF
THE JET IS AIDING PCPN EXPANSION WELL TO THE N OF A NEARLY
STATIONARY SFC FRONT EXTENDING FROM SFC LOW IN NCNTRL KS TO LAKE
ERIE. CLOSER TO HOME...A FEW STRATOCU DEVELOPED IN NE WIND UPSLOPE
AREAS OFF LAKE SUPERIOR EARLIER TODAY. OTHERWISE...HIGH CLOUDS HAVE
BEEN INCREASING AND THICKENING TODAY AFTER MORNING SUNSHINE.
FCST TONIGHT/THU WILL REVOLVE AROUND EVOLUTION OF WINTER STORM
CURRENTLY OVER THE PLAINS. MODELS ARE IN GOOD AGREEMENT SHOWING THE
MID LEVEL LOW OVER KS GRADUALLY TRANSITIONING TO AN OPEN WAVE AS IT
MOVES INTO THE GREAT LAKES REGION LATE THU. MEANWHILE...ASSOCIATED
SFC LOW PRES WILL TRACK FROM NE KS TO SRN LWR MI THU AFTN. INITIAL
BAND OF SNOW CURRENTLY LIFTING TOWARD UPPER MI IS BEING DRIVEN
LARGELY BY AFOREMENTIONED RIGHT ENTRANCE OF UPPER JET AND RESULTING
STRENGTHENING OF LOW/MID LEVEL FGEN AND ISENTROPIC ASCENT. ALTHOUGH
SNOW IS CURRENTLY DEVELOPING/INTENSIFYING WHILE SLOWLY LIFTING N THRU
WI...IT WILL ENCOUNTER VERY DRY AIR AT THE LOWER LEVELS THAT WILL
CONTINUE TO ADVECT S AND W FROM HIGH PRES OVER ONTARIO. SFC DWPTS
HAVE BEEN DOWN INTO THE SINGLE DIGITS ACROSS PORTIONS OF UPPER MI
THIS AFTN AND ARE IN THE NEGATIVE SINGLE DIGITS IN ONTARIO. WITH ONLY
A SLIGHT NORTHWARD SHIFT OF FGEN/ISENTROPIC ASCENT TONIGHT... THE
APPROACHING SNOW IN WI WILL INCREASINGLY STRUGGLE TO MOVE N INTO
UPPER MI AS ADVECTION OF LOW-LEVEL DRY AIR ERODES THE NRN PORTION OF
THE PCPN SHIELD. ALL AVBL HIGH RES MODEL GUIDANCE...INCLUDING HOURLY
RAP RUNS TODAY AND 18Z NAM...SHOW PCPN HAVING TROUBLE LIFTING MUCH
FARTHER THAN FAR SCNTRL UPPER MI TONIGHT WITH NORTHWARD EXTENT FROM
ROUGHLY JUST N OF IRON MOUNTAIN TO JUST N OF MANSTIQUE BY 12Z THU.
DURING THU MORNING...DEFORMATION SNOW SHIELD...WHICH IS CURRENTLY
PRODUCING CONSIDERABLE LIGHTNING/TSSN ACROSS PORTIONS OF
NEBRASKA...WILL SHIFT INTO THE UPPER GREAT LAKES IN A WEAKENING
STATE. AS THIS OCCURS...SNOW SHOULD EXPAND INTO PORTIONS OF NCTNRL
AND NE UPPER MI. SNOW WILL THEN DIMINISH/END STEADILY FROM W TO E
DURING THE AFTN.
FOR THIS EVENT...DO NOT EXPECT ANY SNOW TO FALL FROM IRONWOOD TO
L`ANSE INTO THE KEWEENAW. IT`S QUESTIONABLE WHETHER ANY SNOW WILL
REACH MARQUETTE. TO THE S AND E...EXPECT A SIGNIFICANT GRADIENT OF
SNOWFALL FROM N TO S WITH WITH AMOUNTS RANGING FROM AROUND 1 INCH
NEAR LAKE SUPERIOR TO ABOUT A FOOT IN THE CITY OF MENOMINEE. THE NRN
EDGE OF THE SNOW WILL BE THE MOST DIFFICULT CHALLENGE AS DRY AIR
CONTNUALLY EATS AWAY AT SNOW LIFTING INTO THE AREA UNDER WEAKENING
FORCING. WOULD NOT BE SURPRISED IF THE NRN EXTENT OF SNOWFALL
REFLECTED IN THIS FCST DOES NOT OCCUR. HAVE ADDED DICKINSON/NRN
SCHOOLCRAFT/LUCE COUNTIES TO ADVY...THOUGH IT WILL ONLY BE THE SRN
PARTS OF THOSE COUNTIES THAT WILL REACH THE LOW SLR ADVY CRITERIA OF
AT LEAST 2-4 INCHES OF SNOW ACCUMULATION. FAR SRN PARTS OF DELTA AND
SCHOOLCRAFT COUNTIES MAY SEE STORM TOTAL SNOW UP AROUND 6 INCHES.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 516 PM EDT WED MAR 23 2016
MODELS WERE IN GENERAL AGREEMENT THAT TROUGHING OVER THE CNTRL CONUS
WITH THE NRN STREAM DOMINATING THE NRN LAKES...WILL GIVE WAY TO MID
LEVEL RIDGING AS A SRN STREAM TROUGH DIGS INTO THE GREAT BASIN.
THURSDAY NIGHT...AS THE STRONG SHRTWAVE TROUGH LIFT QUICKLY TO THE
NE THROUGH LOWER MI DURING THE EVENING STRONG 700-300 MB QVECTOR DIV
MOVING INTO THE ERN CWA WILL END THE LINGERING SNOW WITH LITTLE
ADDITIONAL ACCUMULATIONS. MID LEVEL AND SFC RIDGING BUILDING INTO
THE AREA OVERNIGHT WILL BRING CLEARING SKIES AND GOOD RADIATIONAL
COOLING CONDITIONS FAVORING TEMPS NEAR THE LOWER END OF
GUIDANCE...ESPECIALLY INLAND WEST HALF.
FRIDAY...SRLY FLOW AND WAA WILL DEVELOP AS THE RIDGE DEPARTS TO THE
EAST. SUNSHINE WILL ALLOW TEMPS TO CLIMB NEAR OR ABOVE SEASONAL
AVERAGES WITH HIGHS IN THE UPER 30S N AND E TO HE LOWER TO MID 40S
OVER THE SW.
FRI NIGHT THROUGH SAT NIGHT...MODELS SHOW PCPN ASSOCIATED WITH MID
LEVEL SHORTWAVE AND SFC TROUGH SPREADING ACROSS UPPER MICHIGAN. WITH
ONLY MODEST DYNAMICS AND MOISTURE INFLOW...GENERALLY LIGHT AMOUNTS
OF AROUND 0.10 INCH OR LESS IS EXPECTED. FCST LOW LEVEL THICKNESS
AND WET-BULB ZERO HEIGHTS SUGGEST THAT THE PCPN MAY FALL AS
RAIN...ESPECIALLY OVER THE SOUTH AND EAST DURING PEAK HEATING
SATURDAY.
SUN-MON...WITH SFC RIDGING AND A DRY AIRMASS OVER THE AREA...EXPECT
LITTLE PCPN DESPITE POTENTIAL FOR WEAK NRN STREAM SHRTWVS TO BRUSH
THE AREA. TEMPS SHOULD REMAIN NEAR SEASONAL AVERAGES.
TUE-WED...MILDER AIR IS EXPECTED TO SPREAD INTO THE REGION WITH A
STRENGTHENING WAA PATTERN AHEAD OF A TROUGH DEVELOPING OVER THE ERN
PLAINS. SOME LIGHT PCPN...MAINLY AS RAIN...MAY SPREAD TOWARD THE
AREA BY WED AS MOISTURE ADVECTION ALSO INCREASES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 134 AM EDT THU MAR 24 2016
BEING WELL N OF A WINTER STORM THAT WILL BE TRACKING INTO THE GREAT
LAKES REGION...KIWD/KCMX WILL REMAIN VFR THRU THE FCST PERIOD UNDER
AN E TO NE FEED OF DRY AIR AT THE LOW LEVELS. THE NRN FRINGE OF SNOW
ASSOCIATED WITH THE STORM SYSTEM WILL BRUSH KSAW THU MORNING INTO
THU AFTERNOON. IF SO...VFR CONDITIONS MAY FALL TO MVFR AT THAT TIME.
OTHERWISE...VFR CONDITIONS WILL PREVAIL AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 528 PM EDT WED MAR 23 2016
E TO NE WINDS UP TO 25 TO 30KT ARE EXPECTED TONIGHT INTO THU AS PRES
GRADIENT TIGHTENS OVER THE UPPER LAKES BETWEEN HIGH PRES DRIFTING
ACROSS ONTARIO INTO QUEBEC AND LOW PRES TRACKING FROM THE CENTRAL
PLAINS TO FAR SOUTHERN ONTARIO BY LATE THU EVENING. WINDS WILL
QUICKLY DIMINISH TO 15KT OR LESS FROM W TO E LATE THU AFTN THRU FRI
MORNING AS A HIGH PRES RIDGE ARRIVES. THERE WILL BE SOME INCREASE IN
WINDS LATER FRI INTO SAT AHEAD OF THE NEXT LOW PRES TROF. SOUTHERLY
WINDS OVER THE E HALF OF LAKE SUPERIOR MAY INCREASE INTO THE 15-25KT
RANGE FOR A TIME AHEAD OF THE TROF FRI NIGHT INTO SAT. LIKEWISE...
THERE MAY BE 15-25KT NW WINDS FOR A TIME IN THE WAKE OF THE TROF
PASSAGE LATE SAT/SAT NIGHT. WINDS WILL BECOME LIGHT AGAIN LATER SUN
AS A HIGH PRES RIDGE ARRIVES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 6 AM THIS MORNING TO 5 PM EDT THIS
AFTERNOON FOR MIZ007-014-085.
WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ013.
WINTER STORM WARNING UNTIL 1 PM CDT THIS AFTERNOON FOR MIZ012.
WINTER WEATHER ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR MIZ011.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LMZ221-248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1212 AM EDT THU MAR 24 2016
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 327 PM EDT WED MAR 23 2016
LOW PRESSURE WILL TRACK ACROSS SOUTHERN LOWER MICHIGAN TONIGHT
AND THURSDAY AND BRING A WIDE RANGE OF WEATHER. UP TO A FOOT OF
SNOW AND SIGNIFICANT ICING IS POSSIBLE ACROSS THE NORTHERN HALF OF
LOWER MICHIGAN. A MIXTURE OF RAIN...SLEET AND FREEZING RAIN IS
EXPECTED ACROSS CENTRAL LOWER MICHIGAN AND RAIN ACROSS THE SOUTH.
THERE COULD BE A FEW THUNDERSTORMS ACROSS FAR SOUTHERN LOWER
MICHIGAN ON THURSDAY. THE STORM WILL BE TAPERING OFF TO SNOW
SHOWERS THURSDAY NIGHT.
&&
.UPDATE...
ISSUED AT 912 PM EDT WED MAR 23 2016
NO HEADLINE OR FCST CHANGES ARE NECESSARY THIS EVENING. A MIX OF
HEAVY WET SNOW AND FREEZING RAIN WILL CONTINUE ACROSS THE WARNING
AREA OVERNIGHT INTO THURSDAY WITH TOTAL ICE ACCUMULATIONS OF A
QUARTER TO HALF AN INCH AND LOCALLY HIGHER AMOUNTS IN EXCESS OF A
HALF AN INCH POSSIBLE.
TOTAL SNOW ACCUMULATIONS OF 5 TO 9 INCHES ARE ANTICIPATED OUR FAR
NORTHERN FCST AREA WHERE PCPN WILL FALL PREDOMINANTLY IN THE FORM
OF SNOW. THE COMBINATION OF HEAVY WET SNOW AND FREEZING RAIN AND
BREEZY CONDITIONS WILL RESULT IN SCATTERED TO POTENTIALLY NUMEROUS
POWER OUTAGES ACROSS PORTIONS OF THE WARNING AREA.
FURTHER SOUTH FOR THE COUNTIES IN THE ADVISORY A MIX OF RAIN AND
FREEZING RAIN WILL CONTINUE THROUGH THE LATE EVENING HOURS THOUGH
PCPN WILL FALL MORE IN THE FORM OF PLAIN RAIN THAN FZRA. EVEN SO
SOME LIGHT ICING IS POSSIBLE PARTICULARLY ACROSS NORTHERN MKG...
KENT... IONIA AND CLINTON COUNTIES.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 327 PM EDT WED MAR 23 2016
NO SIGNIFICANT CHANGES TO THE FORECAST AS THE 12Z MODEL GUIDANCE
REMAINS IN GOOD AGREEMENT AND THE HRRR SUPPORTS THE GOING FORECAST
FOR EVOLUTION OF P TYPE TONIGHT. WE EXPECT THE NORTHERN TIER TO
SEE THE HIGHEST SNOW AMOUNTS WITH WITH A BAND OF SLEET OR FREEZING
RAIN CUTTING SNOW ACCUMULATIONS SHARPLY TO THE SOUTH.
THE ICING THREAT STILL APPEARS TO BE CENTERED AROUND THE AREA
FROM ALMA TO MT PLEASANT AND WEST TO BIG RAPIDS WHERE A QUARTER TO
HALF INCH OF ICE ACCUM IS POSSIBLE. THE SOUTHERN EDGE OF THE
FREEZING RAIN IS STILL EXPECTED TO BE ALONG OR JUST NORTH OF I-96
TONIGHT.
WE ALSO HAVE TO CONTEND WITH THUNDERSTORM POTENTIAL FOR THE
SOUTHERN BORDER OF THE FORECAST AREA ON THURSDAY AS THERE IS SOME
INSTABILITY THAT IS SFC BASED DURING THE AFTERNOON. WILL CONTINUE
TO HAVE THUNDER IN THE FAR SOUTHERN ZONES.
THE LOW MOVES EAST LATE THURSDAY WITH A NORTH FLOW OF COLDER AIR
CHANGING PRECIP OVER TO SNOW SHOWERS DURING THE EVENING ACROSS THE
ENTIRE FORECAST AREA. A QUICK INCH OR TWO OF SNOW IS POSSIBLE
CROSS MUCH OF THE FORECAST AREA DEPENDING ON HOW THE DEFORMATION
ZONE PIVOTS THROUGH. WINDS GUSTING TO 25 MPH COULD CAUSE PROBLEMS
IF ICE ACCUMULATIONS PERSIST INTO THURSDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 327 PM EDT WED MAR 23 2016
HE LONG TERM PORTION OF THE FCST LOOKS LIKE WE WILL SEE MORE
OCCASIONAL WET WEATHER...AS HAS BEEN THE CASE FOR THE PAST FEW WEEKS.
DRIER WEATHER FROM THE END OF THE SHORT TERM ON FRI WILL REMAIN INTO
AT LEAST THE FIRST PART OF SAT BEFORE PCPN CHCS WILL INCREASE LATER.
A SHORT WAVE ROUNDING THE BASE OF A LONGER WAVE TROUGH ACROSS THE
PLAINS WILL LIFT JUST NW OF THE AREA LATE SAT AND SAT NIGHT. THIS
WILL PUSH A FRONT INTO THE AREA. THE FRONT WILL NOT MAKE IT FAR SE
WITH UPPER WAVE STAYING NW. WE WILL ALSO HAVE ANOTHER WAVE FROM THE
SRN JET LIFT OUT OF THE PLAINS AND GO JUST SOUTH OF THE STATE. RAIN
CHCS WILL BE MUCH BETTER ON SUN WITH THE SRN STREAM WAVE AS IT WILL
DRAW GULF MOISTURE NWD. PCPN LOOKS TO BE MAINLY RAIN THROUGH SUN AS
THE COLDER AIR FROM THE NW GETS HELD UP. PCPN COULD EVENTUALLY
CHANGE OVER TO SOME SNOW AT THE END OF THE EVENT AS SOME COLDER AIR
DOES FINALLY TRY TO MAKE IT IN ON THE BACKSIDE OF THE SYSTEM.
WE SHOULD THEN SEE A BREAK IN THE WEATHER FROM LATER MON THROUGH
TUE/TUE NIGHT. THE UPPER PATTERN OVER NORTH AMERICA WILL BE RATHER
AMPLIFIED WITH THE STRONGER SYSTEM EXITING TO THE EAST...AND ANOTHER
LONG WAVE TROUGH SETTING UP ACROSS THE WRN PORTION OF THE COUNTRY.
WE WILL END UP WITH THE UPPER RIDGE HOLDING IN OVER OUR PORTION OF
THE COUNTRY.
THE THREAT FOR PCPN WILL THEN INCREASE ONCE AGAIN AT THE END OF THE
LONG TERM. THE UPPER RIDGE WILL MOVE FAR ENOUGH EAST THAT WAVES
EJECTING FROM THE WRN TROUGH/LOW WILL START TO IMPACT THE AREA
AROUND WED. THIS COULD END UP GETTING PUSHED BACK OVER TIME AS IS
THE CASE MANY TIMES IN THIS TYPE OF A PATTERN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1212 AM EDT THU MAR 24 2016
POOR AVIATION CONDITIONS ARE EXPECTED THE REMAINDER OF THE NIGHT
AND THROUGH MUCH OF THE DAY ON THURSDAY. IFR CONDITIONS ARE
TRENDING TO LIFR ACROSS THE TAF SITES AT THIS TIME. BY
MORNING...ALL TAF SITES SHOULD BE IN THE LIFR CATEGORY.
PRECIPITATION THE REST OF TONIGHT SHOULD BE LIGHT DRIZZLE OF LIGHT
RAIN AT MOST SITES AND LIGHT FREEZING RAIN AT KMKG.
AFTER 12Z...THE PRECIPITATION SHOULD BE ALL RAIN ON THURSDAY
BEFORE ENDING AS A LITTLE BIT OF LIGHT SNOW OR FLURRIES. CEILINGS
WILL REBOUND THURSDAY EVENING TO MVFR.
&&
.MARINE...
ISSUED AT 327 PM EDT WED MAR 23 2016
SMALL CRAFT ADVISORY WILL CONTINUE THROUGH THURSDAY NIGHT.
CONDITIONS SHOULD IMPROVE BY FRIDAY.
&&
.HYDROLOGY...
ISSUED AT 239 PM EDT WED MAR 23 2016
WIDESPREAD PRECIPITATION AMOUNTS OF 0.75-1.50 INCHES ARE EXPECTED
THROUGH FRIDAY MORNING. RIVER RISES WILL OCCUR... BUT NO SIGNIFICANT
FLOODING IS EXPECTED.
MINOR FLOODING IS CERTAINLY POSSIBLE... MAINLY IN THE FORM OF
NUISANCE FLOODING IN LOWLAND AREAS NEAR RIVER BANKS. AS OF THIS
WRITING... RIVER FLOOD ADVISORIES WERE IN EFFECT FOR THE MAPLE
RIVER AT MAPLE RAPIDS... GRAND RIVER AT IONIA... LOOKING GLASS
RIVER AT EAGLE... AND SYCAMORE CREEK AT HOLT.
ADDITIONAL PRECIPITATION IS EXPECTED SUNDAY INTO SUNDAY
NIGHT...WHICH WILL PROLONG ELEVATED RIVER LEVELS AND COULD RESULT IN
ADDITIONAL MINOR FLOODING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 8 AM EDT THURSDAY FOR MIZ050-
056>059.
WINTER STORM WARNING UNTIL 8 PM EDT THURSDAY FOR MIZ037>040-
043>046-051-052.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EDT FRIDAY FOR LMZ844>849.
&&
$$
UPDATE...LAURENS
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...NJJ
AVIATION...DUKE
HYDROLOGY...EBW
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1237 AM CDT THU MAR 24 2016
.UPDATE...
ISSUED AT 1237 AM CDT THU MAR 24 2016
THE UPR LOW IS CURRENTLY BETWEEN HJH-BIE. THE DEFORMATION SNOW
BAND IS NOW MOVING THRU THE HEART OF THE FCST AREA. THE HIGHEST Z
IS PRODUCING MDT SN IN 1/2 MI VSBYS.
THE 18Z/00Z 4KM NAM NEST AND THE 03Z/04Z HRRR SIM Z DEPICT THIS
BAND WELL. IT WILL CONT TO DRIFT E THRU THE OVERNIGHT HRS WITH THE
BACK EDGE REACHING HWY 281 BY 09Z. BY DAWN THE SNOW SHOULD BE
COMPLETELY OUT OF THE FCST AREA (E OF HWY 81). THE INTENSITY OF
THE BAND SHOULD DIMINISH AS IT MOVES E WITH THE UPR LOW.
THERE WILL BE 1-2" OF ACCUM WHERE THE MDT SNOW PERSISTS THE
LONGEST.
WINDS CONT TO GUST TO NEAR 40 KTS. THE HIGH WIND WRNG WAS
CANCELLED EARLY. PLEASE SEE THE LATEST LSR FOR A LIST OF PEAK WIND
GUSTS OVER THE LAST 18 HRS.
THE HIGHEST GUST WAS 53 KTS AT ORD.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY DAYTIME)
ISSUED AT 321 PM CDT WED MAR 23 2016
FOCUS IS ON THE WINTER STORM SYSTEM TRACKING ACROSS THE PLAINS
TODAY/THIS EVENING. WATER VAPOR IMAGERY PLACED THE CENTER OF THE
UPPER LOW PRESSURE SYSTEM IN WESTERN KANSAS AROUND MID DAY WITH THE
ASSOCIATED SURFACE LOW NEAR KHYS. SURFACE COLD FRONTAL BOUNDARY IS
FAIRLY STATIONARY ATTM FROM JUST SOUTH OF KJYR TO KHLC. POST FRONTAL
TEMPS HAVE BEEN FAIRLY STEADY OR FALLING TODAY WHILE AHEAD OF THE
FRONT IN GOOD INSOLATION TEMPS HAVE REACHED THE 70S. MONITORING THE
WARM SECTOR AREA FOR CONVECTIVE POTENTIAL THIS AFTN AND EVENING AND
IF STORMS DEVELOP CANNOT RULE OUT THE POTENTIAL FOR SMALL HAIL.
INSTABILITY IS ALSO PRESENT FARTHER WEST BEHIND THE FRONT AND
LIGHTNING HAS BEEN COMMON ACROSS PORTIONS OF WESTERN NEBRASKA WITH
SNOW/SLEET/GRAUPEL FALLING AND COULD SEE THIS MOVING INTO OUR
WESTERN COUNTIES THIS EVENING.
AS WE HEAD INTO THIS EVENING AND TONIGHT TAKE NOTE THAT THE
PROGRESSION OF THE WINTER STORM SYSTEM HAS SLOWED...WITH THE BRUNT
OF THE PRECIPITATION MOVING IN AND FALLING DURING THE EVENING/FIRST
PART OF THE NIGHT BEFORE ENDING BY DAYBREAK THURS. AT THE ONSET PCPN
TYPE WILL BE LIQUID AS DRIZZLE/RAIN BEFORE TRANSITIONING TO SNOW AS
COLDER AIR ADVECTS SOUTH. OUR WESTERN CWA SHOULD SEE A TRANSITION TO
SNOW TOWARD 00Z WITH THE SNOW LINE GRADUALLY SHIFTING SOUTHEAST THIS
EVENING/OVERNIGHT. SNOW ACCUMULATIONS ARE TRICKY AS TEMPS ARE
EXPECTED TO BE IN THE 30S WHILE PCPN IS FALLING AND GROUND TEMPS ARE
WARM...AND ULTIMATELY THE GREATER ACCUMULATIONS WILL BE IN SNOW
BANDS. MODELS ARE FAIRLY CONSISTENT THAT THE MAIN SNOW BAND WILL SET
UP ACROSS OUR NW CWA INITIALLY AND SHIFT EAST OVERNIGHT WITH THE
NORTHERN PORTION OF CWA EXPECTED TO SEE THE POTENTIAL FOR THE
GREATER SNOW AMOUNTS. GENERALLY EXPECT AMOUNTS TO RANGE FROM 1 TO 4
INCHES BUT CANNOT RULE OUT LOCALLY HIGHER AMOUNTS IF THE SNOW BAND
IS MORE STATIONARY/NOT PROGRESSIVE. ADJUSTMENTS TO HEADLINES WERE
MADE EARLIER TO DELAY THE TIMING OF THE ONSET OF THE WINTRY WEATHER
AND HARD TO ADJUST HEADLINES ANY FURTHER ATTM AS PCPN HAS YET TO
MOVE IN AND WILL NEED TO MONITOR HOW SYSTEM EVOLVES THRU THE EVENING.
WINDS ARE THE NEXT CONCERN INTO THE NIGHT. WINDS HAVE BEEN STRONG
ALL DAY WITH GUSTS OF 40 TO 50 MPH...AND A RECENT GUST OF 56 MPH AT
KRSL THIS AFTN. WINDS ARE EXPECTED TO REMAIN STRONG THRU THE EVENING
IN A STILL TIGHT PRESSURE AS THE SFC LOW TRACKS EAST INTO NORTHERN
MO. PRESSURE RISES ARE IMPRESSIVE THIS EVENING ACROSS NORTHERN KS
AND WIND GUSTS NEAR OR ABOVE 50 MPH REMAIN POSSIBLE AND THE HIGH
WIND WARNING IS IN EFFECT FOR THE STRONG WINDS.
PRECIPITATION ENDS W/E TONIGHT AS THE SYSTEM PULLS OUT. WIND SPEEDS
WILL REMAIN STEADY/GUSTY THROUGH THE NIGHT BUT WILL GRADUALLY
DECREASE HEADING INTO THURSDAY AS THE GRADIENT RELAXES. OVERNIGHT
TEMPS WILL BE COLD...FALLING BELOW FREEZING. SUNSHINE IS EXPECTED
THURSDAY BUT KEPT TEMPS ON THE COLD SIDE ESPECIALLY FOR OUR NORTHERN
ZONES WHERE SNOW COVER IS EXPECTED.
.MID TERM...(THURSDAY EVENING THROUGH SATURDAY DAYTIME)
ISSUED AT 321 PM CDT WED MAR 23 2016
SUMMARIZING THIS 48-HOUR "MID TERM" PERIOD: ALTHOUGH NOT NEARLY
AS ACTIVE AS THE SHORT TERM WEATHER DESCRIBED ABOVE...THESE
PERIODS ARE NOT EXACTLY QUIET EITHER...AS THERE ARE SOME LOW-
CONFIDENCE/"PESKY" PRECIPITATION CHANCES TO CONTEND
WITH...POSSIBLY AS EARLY AS FRIDAY DAYTIME...BUT MORE SO FRIDAY
NIGHT INTO SATURDAY AND GENERALLY FAVORING THE SOUTHERN CWA MORE
THAN THE NORTHERN COUNTIES. FORTUNATELY...BARRING SOME FAIRLY
SIGNIFICANT CHANGES...THERE DOES NOT APPEAR TO BE ANY "HIGH
IMPACT" WEATHER DURING THIS TIME FRAME...WITH MOST OF THESE STILL-
LOW PRECIPITATION CHANCES FAVORING RAIN MORE THAN SNOW VERSUS
SNOW. THAT BEING SAID...IF HIGH TEMPERATURES FOR SATURDAY CONTINUE
TO TREND DOWN MUCH MORE... ESPECIALLY ABOUT THE NORTHWEST HALF OF
THE CWA COULD POSSIBLY SEE SOME SOME MINIMAL SNOW ACCUMULATION...
SO THIS WILL NEED WATCHED. WHAT WE DO KNOW IS THAT SATURDAY IS
TRENDING RATHER BREEZY/WINDY OUT OF THE NORTH...ALBEIT NORTHING AS
STRONG AS WHAT WE ARE EXPERIENCING WITH THIS CURRENT SYSTEM.
FIRE WEATHER CONCERNS FRIDAY?: TECHNICALLY SPEAKING...A FEW OF OUR
EXTREME SOUTHEASTERN COUNTIES (OSBORNE/MITCHELL) ARE NOW FORECASTED
TO HIT "NEAR-CRITICAL" THRESHOLDS OF RELATIVE HUMIDITY (RH)/WIND
GUSTS ON FRIDAY AFTERNOON...AS RH VALUES DROP TO AROUND 25 PERCENT
AND SOUTHERLY WIND GUST TO 20+ MPH. HOWEVER...AT LEAST FOR NOW...WE
APPEAR "SAFE" FROM CRITICAL THRESHOLDS THAT MIGHT REQUIRE HEADLINE
ISSUANCE. CONSIDERED ADDING THIS VERY LIMITED "NEAR-CRITICAL" AREA
TO THE LATEST HAZARDOUS WEATHER OUTLOOK PRODUCT (HWOGID)...BUT GIVEN
THIS IS STILL 2 DAYS AWAY...IT`S MARGINAL...AND COULD BE MITIGATED
SOMEWHAT BY ANY MEANINGFUL PRECIPITATION THAT FALLS DURING THESE
NEXT 24 HOURS...OPTED TO LEAVE IT OUT FOR NOW AND DEFER TO LATER
SHIFTS TO EVALUATE. AS FOR SATURDAY...ALTHOUGH THERE IS PLENTY OF
WIND...COOLER TEMPS WILL KEEP RH VALUES WELL-ABOVE EVEN "NEAR-
CRITICAL" THRESHOLDS.
WILL NOW TAKE A LOOK AT EACH OF THESE 4 FORECAST PERIODS IN MORE
DETAIL:
THURSDAY EVENING/NIGHT: MAINTAINED A DRY FORECAST HERE...ALTHOUGH DO
EXPECT SKIES TO GENERALLY TREND FROM MOSTLY CLEAR TO PARTLY/MOSTLY
CLOUDY AS THE NIGHT WEARS ON. IN THE MID-UPPER LEVELS...A VERY
FLEETING/BRIEF PERIOD OF SHORTWAVE RIDGING IS EVIDENT JUST AHEAD OF
THE NEXT...FAIRLY LOW-AMPLITUDE SHORTWAVE TROUGH APPROACHING THE
CENTRAL PLAINS FROM THE NORTHERN ROCKIES. AT THE SURFACE...BREEZES
START OUT THE EVENING LIGHT AND SOMEWHAT VARIABLE AS A BRIEF PERIOD
OF RIDGING PASSES BY...BUT LATER IN THE NIGHT A STEADIER 5-15 MPH
SOUTHERLY BREEZE WILL BECOME ESTABLISHED. AS A RESULT OF THE
EXPECTED CHANGES IN SKY COVER/WIND SPEEDS DURING THE NIGHT...LOW
TEMPS MAY VERY WELL OCCUR CLOSER TO MIDNIGHT THAN SUNRISE...WITH
SOME SLIGHT RISES POSSIBLE LATE IN THE NIGHT. CHANGED THESE LOWS
VERY LITTLE...STILL AIMING MOST AREAS INTO THE 28-32 RANGE.
FRIDAY DAYTIME: CONTEMPLATED "RUINING" THE GOING DRY FORECAST BY AT
LEAST ADDING A GENERIC "SLIGHT CHANCE OF SPRINKLES" TO AT LEAST
PORTIONS OF THE CWA...BUT WITH THE LOWEST LEVELS REMAINING FAIRLY
MOISTURE-STARVED...FEEL THAT MOST OF THE POSSIBLE PRECIP ON FRIDAY
WILL STRUGGLE TO REACH THE GROUND. AS A RESULT...KEPT SKY COVER IN
PARTLY-MOSTLY CLOUDY TERRITORY...BUT KEPT IT DRY FOR NOW...ALTHOUGH
NEXT FEW SHIFTS MAY AT LEAST HAVE TO CONSIDER SPRINKLES IF NOT A
SMALL CHANCE OF MEASURABLE RAIN SHOWERS. IN THE MID-UPPER
LEVELS...THE AFOREMENTIONED SHORTWAVE DISTURBANCE AFFECTS MAINLY
SD/NORTHERN NEB DURING THE DAY...BUT THERE COULD BE JUST ENOUGH LIFT
FOR SOME SPOTTY PRECIP LOCALLY. AT THE SURFACE...A FAIRLY WEAK
FRONT/TROUGH WILL PASS INTO THE CWA OVER THE COURSE OF THE
DAY...TURNING WINDS FROM SOUTHERLY TO MORE WESTERLY AND EVEN
NORTHWESTERLY WITH TIME. ROUGHLY THE SOUTHEASTERN ONE-THIRD OF THE
CWA IS MOST LIKELY TO SEE SOUTH-SOUTHWEST WIND GUSTS AS HIGH AS
AROUND 25 MPH...WITH SPEEDS AT LEAST SLIGHTLY LESS FARTHER TO THE
NORTHWEST. GIVEN THE EXPECTATION OF DECENT CLOUD COVER
OVERALL...NUDGED DOWN HIGH TEMPS 1-2 DEGREES...AIMING FOR A RANGE
FROM MID-50S FAR NORTH TO MID-60S FAR SOUTH.
FRIDAY NIGHT: ALTHOUGH MOST OF THE CWA WILL PROBABLY CONTINUE
STRUGGLING TO SEE MUCH PRECIPITATION...MAINTAINED LOW-CONFIDENCE 20-
30 PERCENT RAIN CHANCES FOR ROUGHLY THE SOUTHERN HALF OF THE
CWA...WHILE ACKNOWLEDGING A SLIGHT CHANCE OF SPRINKLES OR EVEN A FEW
LATE-NIGHT FLURRIES IN NORTHERN ZONES. IN THE MID-UPPER
LEVELS...SOME ADDITIONAL ENERGY MOVES IN FROM THE WEST-SOUTHWEST OUT
AHEAD OF A PRIMARY SHORTWAVE TROUGH MOVING SOUTHEAST INTO THE
CENTRAL ROCKIES. WHILE MOST MODELS DOWNPLAY RAIN POTENTIAL DURING
THE NIGHT...THE 12Z NAM IS A BIT MORE AGGRESSIVE WITH RAIN SHOWER
(POSSIBLY WEAK THUNDERSTORM?) ACTIVITY IN SOUTHERN ZONES THROUGH THE
NIGHT...AND HENCE THE SLIGHTLY HIGHER PRECIP CHANCES HERE. AT THE
SURFACE...THE NET EFFECT OF THE UPPER DISTURBANCES TO BOTH THE NORTH
AND WEST WILL BE TO DRIVE A FAIRLY STRONG COLD FRONT SOUTHWARD
THROUGH THE CWA...WITH NORTH WINDS PICKING UP TO AROUND 20+ MPH IN
MOST AREAS BETWEEN MIDNIGHT-SUNRISE. DESPITE COLD AIR
ADVECTION...THESE WINDS SHOULD KEEP TEMPS FROM DROPPING TOO
FAR...AND ACTUALLY NUDGED UP LOWS VERY SLIGHTLY INTO GENERALLY THE
30-36 RANGE MOST PLACES.
SATURDAY DAYTIME: AS EARLIER MENTIONED...THIS CONTINUES TRENDING
TOWARD BEING A NOT-SO-PLEASANT DAY...WITH DECENT NORTH WINDS
SUSTAINED UP AROUND 20-25 MPH WITH HIGHER GUSTS. BECAUSE MID-UPPER
FORCING LARGELY "SPLITS AROUND" THE CWA...PRECIPITATION CHANCES
REMAIN FAIRLY LOW...RANGING FROM NON-MENTIONABLE (BELOW 15 PERCENT)
IN THE FAR NORTHERN CWA...TO AROUND 30 PERCENT IN SOUTHERN ZONES. IN
FACT...MODELS SUCH AS THE ECMWF/GFS ARE ESSENTIALLY DRY CWA-WIDE.
HOWEVER...THE NAM IS MORE INSISTENT ON A BAND OF RAIN/POSSIBLY WET
SNOW AFFECTING SOUTHERN ZONES DURING THE AFTERNOON...SO HENCE THE
CONTINUED LOW PRECIP CHANCES. NUDGED DOWN HIGHS ABOUT 2
DEGREES...NOW RANGING FROM NEAR-40 FAR NORTH TO MID-UPPER 40S SOUTH.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 320 PM CDT WED MAR 23 2016
THIS SECTION FOCUSES ONLY ON THE "LONG TERM" PERIOD (DAYS 4-7) FOR
WHICH THE FORECAST IS PRIMARILY DERIVED FROM A DEFAULT MULTI-MODEL
BLEND WITH ONLY LIMITED MODIFICATION BY THE FORECASTER:
SUMMARIZING THIS 4-DAY PERIOD: GENERALLY SPEAKING...THINGS START OUT
WITH FAIRLY HIGH CONFIDENCE IN DRY AND SEASONABLE CONDITIONS (EXCEPT
FOR MAYBE SOME RAIN AND/OR SNOW RIGHT AWAY SATURDAY NIGHT IN
SOUTHERN ZONES)...BEFORE LOW-END RAIN CHANCES RE-ENTER THE OFFICIAL
FORECAST BY THE TUES NIGHT-WED TIME FRAME ALONG WITH THE POSSIBILITY
OF AT LEAST LIMITED THUNDERSTORM ACTIVITY (ESPECIALLY BY WEDNESDAY).
AT LEAST FOR NOW...THE ENTIRE SUNDAY DAYTIME-TUESDAY DAYTIME
FORECAST REMAINS VOID OF MENTIONABLE RAIN CHANCES...BUT PLEASE NOTE
THAT THERE ARE HINTS IN THE LATEST ECMWF/GFS THAT FUTURE FORECASTS
MAY BE INTRODUCING SLIGHT RAIN CHANCES AS EARLY AS THE LATE MONDAY
NIGHT-TUESDAY TIME FRAME...SOMETHING TO WATCH FOR. TEMPERATURE-
WISE...HIGHS/LOWS WERE CHANGED VERY LITTLE FROM PREVIOUS
FORECAST...WITH SEASONABLE HIGHS IN THE 50S SUNDAY THEN RISING INTO
THE 60S FOR MOST AREAS MON-WED. AS FOR OVERNIGHT LOWS...SATURDAY
NIGHT IS THE COLDEST OF THESE NIGHTS WITH LOWS WELL DOWN INTO THE
20S...WITH MILDER 30S AND EVEN SOME 40S BY MON NIGHT AND ESPECIALLY
TUES NIGHT.
POSSIBLE ELEMENTS WORTHY OF INCLUSION IN THE HAZARDOUS WEATHER
OUTLOOK (HWOGID): OFFICIALLY...NOTHING YET. FOR ONE...THE
THUNDERSTORM CHANCES JUST INTRODUCED FOR WEDNESDAY WOULD NOT GO INTO
THE HWO UNTIL TONIGHT`S SHIFT. AS FOR POSSIBLE FIRE WEATHER
DAYS...CURRENTLY THERE ARE NONE WITH AN OVERLAP OF RELATIVE HUMIDITY
BELOW 25 PERCENT AND WIND GUSTS ABOVE 20 MPH...BUT THIS WILL BEAR
WATCHING AS THESE CONDITIONS OFTEN DON`T SHOW UP IN MODELS 4+ DAYS
OUT UNLESS THEY ARE PARTICULARLY "BAD".
WILL NOW MENTION A FEW DETAILS ABOUT SPECIFIC PERIODS:
SATURDAY NIGHT: WITH A SHORTWAVE TROUGH PASSING THROUGH THE CENTRAL
PLAINS (BUT MAINLY TO OUR SOUTH)...KEPT SOME 20-30 PERCENT CHANCES
FOR RAIN/SNOW (MORE LIKELY) GOING FOR MAINLY THE SOUTHEAST 1/3 OF
THE CWA. THE ECMWF IS MORE BULLISH THAN THE GFS HERE...AND EVEN
SUGGESTS SOME LIGHT SNOW ACCUMULATION IS POSSIBLE MAINLY IN OUR KS
ZONES.
SUNDAY DAYTIME-NIGHT: CONFIDENCE IS PRETTY DARN HIGH IN A DRY 24
HOURS HERE AS SHORTWAVE RIDGING MOVES IN ALOFT BEHIND THE DEPARTING
WAVE...ALTHOUGH RIGHT AWAY SUNDAY MORNING THE VERY BACK EDGES OF
SNOW COULD STILL BE FLIRTING WITH OUR EXTREME SOUTHEAST CWA BEFORE
DEPARTING WELL TO THE EAST. LIGHTER WINDS THAN SATURDAY AND TEMPS
RISE ANYWHERE FROM 7-15 DEGREES VERSUS SATURDAY...WITH ALL AREAS
INTO THE 50S.
MONDAY DAYTIME-NIGHT: KEPT IT DRY HERE...AND LIKELY WILL BE FOR AT
LEAST THE DAYTIME HOURS...BUT FUTURE FORECASTS MAY NEED TO CONSIDER
SOME SHOWER CHANCES FOR LATE IN THE NIGHT AS THE VERY LEADING EDGES
OF ELEVATED MOISTURE RETURN/LIFT REACHES THE AREA WELL OUT AHEAD OF
A LARGE-SCALE TROUGH OVER THE WESTERN CONUS.
TUESDAY DAYTIME-WEDNESDAY DAYTIME: AT LEAST FOR NOW...TUES DAYTIME
FORECAST REMAINS DRY...BUT THE ENTIRE CWA HAS AT LEAST 20-30 PERCENT
RAIN CHANCES FOR TUES NIGHT-WED AS THE CENTRAL PLAINS BECOMES
INCREASINGLY-INFLUENCED BY THE WESTERN CONUS TROUGH. AS IS USUALLY
THE CASE...MODELS VARY CONSIDERABLY IN THE DETAILS...WITH THE GFS
FAVORING TUES NIGHT PRECIP A BIT MORE AND THE ECMWF MORE-SO FAVORING
WED DAYTIME. OF COURSE...IT`S FUTILE/POINTLESS AT THIS DAY 6-7 RANGE
TO TRY WORKING OUT TIMING DETAILS...SO HENCE THE BLANKET RAIN
CHANCES THE ENTIRE TIME. AS FOR THUNDERSTORM INTENSITY...ALTHOUGH
THIS DOES NOT LOOK LIKE AN "OBVIOUS" SEVERE WEATHER THREAT...IT`S
STILL A WEEK AWAY AND WITH APRIL FAST APPROACHING...IT SURE WON`T
TAKE MUCH TO GET AT LEAST STRONG/MARGINALLY SEVERE STORMS.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THU NIGHT)
ISSUED AT 1237 AM CDT THU MAR 24 2016
SIGNIFICANT WEATHER: IFR SNOW CONTS THRU 09Z THEN ENDS. STRONG N
WINDS.
REST OF TONIGHT: IFR SNOW WITH VSBYS TEMPO DOWN TO 1/2SM...ENDING
09Z-10Z. BECOMING VFR 10Z-12Z. N WINDS WILL CONT TO G40 KTS BUT
GRADUALLY SUBSIDE. CONFIDENCE: HIGH
THU: VFR WITH A FEW PATCHES OF 25K FT CIRROSTRATUS. NNW WINDS CONT
TO DIMINISH BUT WILL STILL GUST UP TO 26 KTS BEFORE 17Z.
CONFIDENCE: HIGH
THU EVE: VFR WITH THICKER 25K FT CIRROSTRATUS MOVING IN FROM THE
W. WINDS DROP BELOW 10 KTS AND SHIFT TO SW. CONFIDENCE: HIGH
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WINTER STORM WARNING UNTIL 7 AM CDT THIS MORNING FOR NEZ041-047-
048-061-062-072>075-082>084.
WINTER STORM WARNING UNTIL 4 AM CDT EARLY THIS MORNING FOR
NEZ039-040-046-060.
WINTER WEATHER ADVISORY UNTIL 7 AM CDT THIS MORNING FOR NEZ049-
063.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...FAY
LONG TERM...PFANNKUCH
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1137 PM CDT WED MAR 23 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 342 PM CDT WED MAR 23 2016
THE SLOWER RAP MODEL AND HRRR MODEL ARE PREFERRED WHICH CONTINUE
SNOW CONTINUING IN EASTERN AREAS FOR A FEW HOURS AFTER MIDNIGHT.
THE BETTER GUESS IS WHEN THE THIRD OF THREE SNOW BANDS DEVELOPS
LATER TONIGHT ACROSS CENTRAL NEBRASKA...THE SECOND ONGOING SNOW
BAND WILL FALL APART.
THE FORECAST BLENDS SOME OF THE SLOWER RAPID UPDATE MODELS WITH
THE PREVIOUS FORECAST WHICH ADDS AN INCH OR TWO SNOW ACCUMULATION
ACROSS SWRN NEB AND PARTS OF THE CENTRAL SANDHILLS. GIVEN THE
WARM GROUND AND SNOWFALL RATES OF AN INCH OR LESS PER HOUR THUS
FAR...FORECAST ACCUMULATIONS COULD ACTUALLY BE TOO HIGH IN THE
LOWER ELEVATIONS.
WIND GUSTS OF 50 TO 55 MPH SHOULD CONTINUE IN THE OPEN AREAS
EARLY THIS EVENING AND THEN DROP OFF. EARLIER GUSTS OF 60 TO 64
MPH HAVE VANISHED. MOST OF THOSE GUSTS WERE MOMENTUM TRANSPORT
FROM 65 KT WINDS AT 3KFT PER KLNX VWP SO THE GUSTS ARE AT THE
MERCY OF VERTICAL MIXING.
SKIES BY MORNING SHOULD BE GENERALLY CLEAR WITH DRIER AIR MOVING
IN AT ALL LEVELS. THE LOWS IN THE TEENS AND LOWER 20S ARE MODEST.
WINDS ALOFT WOULD CONTINUE STRONG PREVENTING A DEEP INVERSION IN
MOST AREAS. THE EXCEPTION IS THE WRN SANDHILLS WHERE SINGLE OR
NEAR SINGLE DIGITS AREA EXPECTED.
ALL FORECAST HIGHLIGHTS WILL OPERATE IN PLACE. NO UPGRADES APPEAR
TO BE NEEDED AT THIS TIME AS THE SYSTEM HAS GENERALLY BEEN WELL-
BEHAVED. THERE IS STILL ROOM FOR A SURPRISE GIVEN THE STRENGTH OF
THIS STORM.
LASTLY...THE OCCASIONAL LIGHTNING AND THUNDERSTORMS ARE THE
RESULT OF ELEVATED CAPE. THE RAP HAS SHOWN ONLY WEAK SKILL WITH
THIS FEATURE. THE 750MB BARRIER JET IS QUITE STRONG.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 342 PM CDT WED MAR 23 2016
A LOW PRESSURE SYSTEM WILL PUSH ACROSS THE NORTHERN PLAINS
THURSDAY NIGHT AND FRIDAY...DRAGGING A COLD FRONT ACROSS THE AREA
LATE IN THE DAY ON FRIDAY. A SLIGHT WARM UP TO AROUND 50 AHEAD OF
THE FRONT. MOISTURE IS LIMITED...HOWEVER MODELS MAY BE UNDERDONE
ON WHAT IS AVAILABLE IN THE BOUNDARY LAYER DUE TO EXPECTED SNOW
MELT/EVAPORATION FROM PRECIP FROM ONGOING STORM. THAT
SAID...MODELS FOCUS MOST OF THE ENERGY ACROSS THE NORTH...WITH
POCKETS ACROSS THE CWA. THUS WILL CONTINUE TO HAVE LOW POPS.
TEMPS COOL OFF BEHIND THE FRONT WITH RAIN POSSIBLY MIXING WITH
SNOW INTO FRIDAY NIGHT. MOST AREAS WILL BE DRY BY
SATURDAY...HOWEVER THE WESTERN SIDE OF THE FRONT STALLS NEAR THE
NEB/KS BORDER AND COLD LINGER SOME RAIN/SNOW ACROSS FAR
SOUTHWESTERN NEB INTO SATURDAY. COLD AIR IS DRAWN IN BEHIND THE
FRONT WITH HIGHS ONLY AROUND 40 FOR SATURDAY. A GOOD 10 TO 15
DEGREES BELOW NORMAL FOR THE LAST WEEK OF MARCH.
WARM FRONT TO PUSH ACROSS THE AREA WITH A WARM UP FOR EASTER
SUNDAY. HIGHS BACK CLOSER TO NORMAL...50S...AND DRY. EVEN
WARMER...60S...FOR MONDAY INTO TUESDAY. THEN THE NEXT SYSTEM
EJECTS ONTO THE PLAINS FOR MID WEEK...AND BRING ANOTHER CHANCE
FOR RAIN/SNOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1137 PM CDT WED MAR 23 2016
CONDITIONS HAVE IMPROVED TO VFR AT KLBF AS THE WESTERN EDGE OF
THE WINTER STORM HAS MOVED EAST INTO CENTRAL AND EASTERN NEBRASKA.
VFR CONDITIONS ARE FORECAST AT THE KLBF AND KVTN TERMINALS THE
NEXT 24HRS. WESTERLY WINDS THURSDAY ARE FORECAST TO BE LIGHT AOB
10KTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 1 AM CDT THURSDAY FOR NEZ010-027>029-
038-059-070.
WINTER WEATHER ADVISORY UNTIL 1 AM CDT THURSDAY FOR NEZ071.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
101 AM CDT THU MAR 24 2016
.UPDATE...
ISSUED AT 100 AM CDT THU MAR 24 2016
INHERITED FORECAST MAINLY ON TRACK. DID LOWER TEMPERATURES SOUTH
WHERE WE ARE BELOW FORECAST MINS. A CLEAR SKY...LIGHT WINDS...AND
DRY AIR ALLOWING TEMPERATURES TO DROP THROUGH THE TEENS OVER THIS
AREA. OTHER CHANGE WAS TO MENTION SLIGHT CH OF LIGHT MIXED
PRECIPITATION NORTHWEST. ECHOS IN NORTHEASTERN MONTANA HOLDING
TOGETHER...SO WANTED TO HAVE SOME MENTION. WILL CONTINUE TO
MONITOR IN CASE POPS NEED TO BE RAISED. MODELS MAINLY DRY AND
DISSIPATE THE PRECIPITATION AS IT MOVES INTO WESTERN ND.
UPDATE ISSUED AT 929 PM CDT WED MAR 23 2016
QUIET WEATHER CONTINUES OVER THE AREA. A FEW VERY LIGHT SHOWERS
NOTED OVER CENTRAL MOVING INTO EASTERN MONTANA...THOUGH HAVE KEPT
OUR FORECAST DRY IN LINE WITH LATEST HIGH RES-GUIDANCE AS SHOWERS
MOVE INTO DRIER AIR. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 622 PM CDT WED MAR 23 2016
QUIET WEATHER CONTINUES OVER MUCH OF THE AREA. MAIN CHANGE TO THE
FORECAST FOR EARLY EVENING UPDATE WAS TO INCREASE CLOUD COVER OVER
THE FAR WEST...THOUGH THESE LOW LEVEL CLOUDS CONTINUE TO SLOWLY
ERODE. HIGHER LEVEL CLOUDS WILL START TO MOVE IN LATER THIS
EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 331 PM CDT WED MAR 23 2016
THE MAIN FORECAST CONCERN IN THE SHORT TERM PERIOD WILL BE THE
POSSIBILITY OF CLOUD COVER IN THE WEST LINGERING INTO THE EARLY
EVENING HOURS. ATTENTION THEN SHIFTS TO THURSDAY FOR SOME POSSIBLE
FIRE WEATHER CONCERNS.
CURRENTLY...COOL AND DRY HIGH PRESSURE CENTER WAS OVER SOUTHEASTERN
MANITOBA...WITH A HIGH PRESSURE RIDGE AXIS EXTENDING SOUTHWESTWARD
FROM THE LOW CENTER. THIS DRY AIR CONTINUED TO MOVE WESTWARD
ACROSS NORTH DAKOTA...ERODING THE CLOUD COVER FROM EAST TO WEST. THE
WESTERN THIRD OF THE STATE REMAINS UNDER SOME STRATUS AND MID-LEVEL
CLOUDS. MEANWHILE A VIGOROUS STORM SYSTEM OVER THE CENTRAL AND
SOUTHERN PLAINS CONTINUED TO PRODUCE GUSTY WINDS...RAIN...AND SNOW
FROM COLORADO TO THE GREAT LAKES.
THE SHORT TERM RAP AND HRRR INDICATE THE CLOUDS OVER WESTERN NORTH
DAKOTA SHOULD BECOME SCATTERED LATE THIS AFTERNOON/EARLY EVENING AS
THE DRIER AIR FROM THE HIGH PRESSURE RIDGE AXIS PUSHES WESTWARD.
TONIGHT AND THURSDAY THE CENTRAL PLAINS STORM CENTER MOVES
EAST...THEN NORTHEAST TOWARDS THE GREAT LAKES. THE NORTHWEST FLOW
ALOFT TONIGHT OVER NORTH DAKOTA IS INTERRUPTED BY A SHORTWAVE RIDGE
OVER THE STATE ON THURSDAY. THIS SHORT-LIVED DRYING OF THE LOW/MID
LAYERS WILL PROVIDE A CHANCE FOR A MIX-OUT SURFACE-TO-H800. THIS IS
SUPPORTED BY FORECAST BUFKIT SOUNDINGS AS WELL. THUS USED A BLEND OF
SHORT TERM AND BCCONSMOS FOR MINIMUM RELATIVE HUMIDITY.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 331 PM CDT WED MAR 23 2016
AN UPPER LEVEL SHORTWAVE OVER THE PACIFIC NORTHWEST TONIGHT MOVES
INTO THE ROCKIES THURSDAY AND INTO THE FRONT RANGE AND WESTERN
DAKOTAS THURSDAY NIGHT. SURFACE LOW PRESSURE DEVELOPS IN RESPONSE
OVER EASTERN MONTANA...WITH COLDER AIR TO THE NORTH IN SOUTHERN
CANADA...AND WARMER AIR TO THE SOUTHWEST OVER WYOMING. A COLD
FRONTAL BOUNDARY DEVELOPS ALONG THE CANADIAN BORDER...WHILE A WARM
FRONT EXTENDING SOUTH FROM THE LOW DEVELOPS THURSDAY NIGHT.
SCATTERED TO ISOLATED AREAS OF RAIN AND SNOW EXPECTED THURSDAY
NIGHT. TEMPERATURE PROFILES SUPPORT WARM AIR ALOFT COINCIDENT WITH
COLDER AIR AT THE SURFACE TO RESULT IN CHANCES OF LIGHT FREEZING
RAIN...MAINLY NORTH CENTRAL COUNTIES THURSDAY NIGHT...AND FOR A
BRIEF HOUR OR TWO POSSIBLE FARTHER SOUTH TOWARDS LAKE SAKAKAWEA AND
INTERSTATE 94 BEFORE/AROUND SUNRISE FRIDAY MORNING.
BY SUNRISE FRIDAY EXPECT SOME LIGHT SNOW ACCUMULATIONS POSSIBLE
ALONG THE CANADIAN BORDER.
FRIDAY AND FRIDAY NIGHT THE UPPER LEVEL SHORTWAVE MOVES SOUTHEAST
ACROSS THE DAKOTAS. THE SURFACE LOW IS FORECAST TO MOVE INTO EASTERN
NORTH DAKOTA BY NOON ON FRIDAY...WITH COLD ADVECTION ALREADY TAKING
PLACE OVER NORTHERN AND INTO SOUTHWESTERN NORTH DAKOTA. INCREASING
CHANCES OF RAIN FRIDAY WITH HIGH CHANCES OF LIGHT SNOW NORTH AND
LIGHT RAIN SOUTH. EXPECT AROUND AN INCH OF SNOW ACCUMULATION DURING
THE DAYTIME FRIDAY. BY FRIDAY NIGHT THE BETTER CHANCES OF
PRECIPITATION ARE ACROSS SOUTHERN NORTH DAKOTA. RAIN CHANGING TO
SNOW WITH A FEW TENTHS OF AN INCH TO 1 INCH OF SNOW POSSIBLE ACROSS
SOUTHERN COUNTIES.
IN SUMMARY...CHANCES OF RAIN AND SNOW THURSDAY NIGHT THROUGH FRIDAY
NIGHT...WITH SOME AREAS OF FREEZING RAIN NORTH CENTRAL LATE THURSDAY
NIGHT INTO EARLY FRIDAY MORNING. SNOW AMOUNTS OF UP TO AN INCH
POSSIBLE...MAINLY ACROSS THE NORTH AND SOUTH CENTRAL...BY DAYBREAK
SATURDAY.
MAINLY DRY FOR THE WEEKEND INTO EARLY NEXT WEEK WITH A SLOW WARMING
TREND.
THE MEDIUM RANGE MODELS ARE STILL IN DISAGREEMENT REGARDING A STORM
SYSTEM FOR NEXT WEEK...BUT THE LATEST 12Z RUNS ARE SHOWING A
POSSIBLE TREND TOWARD BETTER AGREEMENT. THE STORM SYSTEM IS
FORECAST TO DEVELOP FROM A LONGWAVE TROUGH OVER
THE WEST COAST SUNDAY...DEEPENING OVER THE ROCKIES
MONDAY/TUESDAY...AND EXPANDING INTO THE PLAINS TUESDAY
NIGHT/WEDNESDAY WITH THE LONGWAVE TROUGH REMAINING OVER THE CONUS
THROUGH MUCH OF NEXT WEEK. THE GFS HAS BEEN BULLISH ON DEVELOPING
A LARGE STORM SYSTEM REACHING WELL INTO THE NORTHERN PLAINS THAT
WOULD BRING WIDESPREAD RAIN AND SNOW TO NORTH DAKOTA. THE ECMWF IS
NOW DEPICTING A STRONGER SHORTWAVE EJECTING OUT OF THE BASE OF THE
LOW THAT IN TURN DEVELOPS A SURFACE LOW IN A REASONABLY SIMILAR
PLACE IN THE MISSOURI AND UPPER MISSISSIPPI VALLEY. CHANCES OF RAIN
OR SNOW REMAIN IN THE FORECAST FOR TUESDAY/WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 100 AM CDT THU MAR 24 2016
VFR CONDITIONS EXPECTED FOR THE MAJORITY OF THE PERIOD. MAY SEE A
BRIEF PERIOD OF LIGHT FREEZING RAIN OR SLEET AT KISN EARLY THIS
MORNING. NOT ENOUGH CONFIDENCE TO INCLUDE IN THE TERMINAL FORECAST
AT THIS TIME...AND WILL CONTINUE TO MONITOR. DETERIORATING
CONDITIONS THURSDAY NIGHT AND FRIDAY AS A CLIPPER STORM SYSTEM
MOVES INTO THE REGION.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...JV
LONG TERM...JV
AVIATION...NH
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1157 PM CDT WED MAR 23 2016
.UPDATE...
UPDATED FOR THE 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 943 PM CDT WED MAR 23 2016/
UPDATE...
WINDS HAD WEAKENED SOME OVER THE MIDSOUTH FOLLOWING SUNSET... BUT
REMAINED OCCASIONALLY GUSTY ALONG AND WEST OF THE MS RIVER.
CONSIDERED EARLIER DROPPING THE WIND ADVISORY...BUT NAM AND GFS
LAMP GUIDANCE INDICATE A POTENTIAL RETURN TO ADVISORY LEVEL WINDS
AFTER 4 AM...WITH THE APPROACH OF A SURFACE PRESSURE TROF. AN
EARLIER FORECAST UPDATE INCLUDED THUNDERSTORM TIMING ADJUSTMENTS.
00Z NAM AND 01Z HRRR MODEL RUNS WERE IN GOOD AGREEMENT IN
DEVELOPING PREFRONTAL ELEVATED SHOWERS DURING THE OVERNIGHT. BEST
THUNDER POTENTIAL WILL LIKELY ARRIVE OVER EAST AR / NORTHWEST MS
BY 6 AM. THE NAM SHOWED A SHARPLY DEFINED SHORTWAVE TROF ROTATING
THROUGH SOUTHERN MO...AROUND THE BASE OF THE UPPER LOW SHORTLY
AFTER SUNRISE. THIS FEATURE WILL SERVE TO SHARPEN CONVECTIVE FOCUS
OVER WEST TN DURING THE DAYLIGHT MORNING HOURS. TO THE SOUTH... A
SUBTLER SHORTWAVE IS DEPICTED EJECTING FROM THE ARKLATEX INTO THE
NORTH MS BY MIDDAY THURSDAY. THIS LATER FEATURE WILL LIKELY
ENCOUNTER GREATER INSTABILITY OVER NORTHEAST MS...UP TO 1500 J/KG
BY MIDMORNING.
NO ADDITIONAL INFORMATION ON THE STATUS OF THE COLUMBUS AFB
RADAR...KGWX.
CURRENT FORECAST ON TRACK...WITH NO ADDITIONAL CHANGES AT THIS
TIME.
PWB
PREV DISCUSSION... /ISSUED 634 PM CDT WED MAR 23 2016/
DISCUSSION...
AN UPPER LEVEL LOW PRESSURE SYSTEM OVER WESTERN KANSAS THIS
AFTERNOON WILL LIFT OUT TO THE NORTHEAST THROUGH THURSDAY. AS IT
DOES SO...A SHORTWAVE WILL ROTATE THROUGH THE BASE OF THE TROUGH
AND ROTATE ACROSS THE MID SOUTH THURSDAY. STRONG AND GUSTY
SOUTHERLY WINDS SHOULD CONTINUE OVERNIGHT AHEAD OF THIS
SYSTEM...THEREFORE WILL LEAVE THE WIND ADVISORY IN PLACE EVEN
THOUGH IT REMAINS BORDERLINE. SHOWERS AND THUNDERSTORMS SHOULD
DEVELOP ACROSS THE ARKLATEX LATER THIS EVENING AND MOVE INTO
WESTERN SECTIONS OF THE MID SOUTH AFTER MIDNIGHT. INSTABILITY
SHOULD WANE TONIGHT ACROSS OUR AREA SO ANY SEVERE STORMS OVER THE
ARKLATEX SHOULD WEAKEN PRIOR TO REACHING OUR CWA.
AS THE SHORTWAVE ROTATES ACROSS THE REGION...MID LEVEL LAPSE RATES
SHOULD STEEPEN TO BETWEEN 6.5 AND 7.0 C/KM OVER TOP OF A PLUME OF
SURFACE DEWPOINTS RISING INTO THE LOWER 60S ACROSS NORTHEAST
MISSISSIPPI BY EARLY THURSDAY AFTERNOON. AS SURFACE HEATING
COMMENCES THIS SHOULD GENERATE MODEST INSTABILITY WITH CAPE
RANGING FROM 500-1000 J/KG OVER THESE LOCATIONS. THERE REMAINS
MODEL DISAGREEMENT BETWEEN THE LATEST 12Z RUNS...WITH THE NAM AND
TO A LESSER DEGREE THE GFS ON THE HIGHER END OF INSTABILITY WITH
THE ECMWF KEEPING CAPES LESS THAN 500 J/KG. A SLIGHT RISK FOR
SEVERE WEATHER ON THURSDAY STRETCHES ACROSS NORTHEAST MISSISSIPPI
INTO WEST TENNESSEE. THE MOST LIKELY LOCATIONS TO EXPERIENCE
SEVERE STORMS TOMORROW SHOULD BE ACROSS NORTHEAST MISSISSIPPI
WHERE INSTABILITY IS GREATEST. ALL OF THE MODEL GUIDANCE SUGGESTS
STRONG WIND SHEAR THROUGH THE ATMOSPHERE WITH A TENDENCY FOR LOW
LEVEL VEERING OF THE WINDS THROUGH THE DAY. THIS SHEAR IS MORE
THAN SUFFICIENT TO SUPPORT ORGANIZED SEVERE STORMS WHERE IT ALIGNS
WITH THE BEST INSTABILITY. THE PRIMARY THREATS AT THIS TIME APPEAR
TO BE DAMAGING WINDS AND ISOLATED TORNADOES. SHOWERS AND
THUNDERSTORMS SHOULD SHIFT EAST OF THE MID SOUTH BY THURSDAY
EVENING.
HIGH PRESSURE WILL BUILD BACK INTO THE REGION FRIDAY WITH A RETURN
TO DRY WEATHER AND COOLER TEMPERATURES. THIS HIGH PRESSURE WILL
SHIFT EAST BY THE WEEKEND WITH WARMER TEMPERATURES EXPECTED.
ANOTHER SHORTWAVE WILL MOVE ACROSS THE REGION SUNDAY AND SUNDAY
NIGHT WITH ADDITIONAL STORM CHANCES. ANOTHER BRIEF COOL DOWN IS
ANTICIPATED MONDAY BEFORE WARMING BACK TO NEAR OR SLIGHTLY ABOVE
AVERAGE TEMPERATURES THROUGH THE MIDDLE OF NEXT WEEK.
JLH
&&
.AVIATION...
06Z TAF CYCLE
VFR CONDITIONS WILL CONTINUE FOR A FEW MORE HOURS. CEILINGS WILL
DROP TO MVFR LEVELS EARLY THURSDAY MORNING WITH A RETURN TO VFR
CONDITIONS IN THE AFTERNOON. SHOWERS AND THUNDERSTORMS WILL MOVE
INTO WESTERN SECTIONS OF THE FORECAST AREA BEFORE SUNRISE AND WILL
PUSH EAST WITH ACTIVITY EXITING THE EASTERN PART OF THE FORECAST
AREA BY LATE AFTERNOON. WINDS WILL BE MAINLY FROM THE SOUTH AT 15
TO 20 KNOTS WITH OCCASIONAL HIGHER GUSTS. WINDS WILL BECOME MORE
WESTERLY BY THURSDAY AFTERNOON AND THEN WILL BE FROM THE NORTHWEST
IN THE EVENING.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR DUNKLIN-PEMISCOT.
MS...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR COAHOMA-DESOTO-PANOLA-
QUITMAN-TALLAHATCHIE-TATE-TUNICA.
TN...WIND ADVISORY UNTIL 7 AM CDT THURSDAY FOR DYER-LAKE-LAUDERDALE-
OBION-SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1146 PM CDT WED MAR 23 2016
.AVIATION...
SHOWERS AND THUNDERSTORMS WERE DEVELOPING ALONG A COLD FRONT THAT
WAS MOVING THROUGH THE CENTRAL PART OF THE STATE AT 0430Z. TWEAKED
THE TIMING OF THE FRONTAL PASSAGE AFTER COMPARING THE CURRENT
RADAR WITH THE HIGH RESOLUTION MODELS. BOTH THE RAP13 AND HRRR ARE
CLOSE WITH THE CURRENT WIND SHIFT OUT WEST AND THE FRONTAL PASSAGE
THROUGH SE TEXAS.
SINCE THE MODELS ARE CONSISTENT IN ERODING THE STRONG INVERSION AT
850 MB LATER TONIGHT...DO EXPECT A TWO TO THREE-HOUR PERIOD OF
SHOWERS WITH ISOLATED THUNDERSTORMS AHEAD OF THE FRONTAL PASSAGE.
THE BREEZY WINDS AHEAD OF THE FRONT WILL LIKELY DIMINISH BEFORE
BECOMING SOUTHWEST AND WEST AHEAD OF THE FRONT...AND THEN
NORTHWEST AND BECOMING BREEZY AGAIN BEHIND THE FRONT DURING THE
DAY ON THURSDAY. AM EXPECTING AT LEAST MVFR CONDITIONS AHEAD OF
THE FRONT WITH A SLIGHT CHANCE THAT IFR CONDITIONS COULD DEVELOP
IN THE STRONGER STORMS AND HEAVIER SHOWERS. THERE IS ALSO A
MARGINAL CHANCE FOR AN ISOLATED STRONG OR EVEN SEVERE THUNDERSTORM
WITH WIND AND HAIL THE MAIN THREATS...MAINLY FROM METRO HOUSTON
NORTH TO KCLL AND KUTS.
40
&&
.PREV DISCUSSION... /ISSUED 901 PM CDT WED MAR 23 2016/
UPDATE...
AT 700 PM...DEEP LOW PRESSURE WAS LOCATED OVER NE KANSAS. A
PRE FRONTAL TROUGH EXTENDED FROM THE LOW INTO NORTH CENTRAL TEXAS
AND A COLD FRONT TRAILED TO THE WEST EXTENDING FROM THE SFC LOW
ACROSS THE TEXAS PANHANDLE. 00Z SOUNDINGS FROM CRP AND LCH
CONTINUE TO SHOW A STOUT CAP IN PLACE NEAR 850 MB. 850 MB DEW
POINTS ARE AROUND 10 C BUT MOISTURE LEVELS DRY OUT QUICKLY AT 700
MB. AT 300 MB...A DEEP UPPER LOW WAS SPINNING OVER THE
KANSAS/NEBRASKA WITH A 90-100 KT JET TO THE E-SE OF THE LOW. WEAK
DIVERGENCE IS NOTED OVER NE TEXAS.
THE SPEED MAX ON THE EAST SIDE OF LOW WILL MOVE NE TONIGHT AND SE
TX WILL LIE IN A RIGHT REAR QUAD BETWEEN 06-12Z WHICH IS THE SAME
TIME THE COLD FRONT WILL BE CROSSING THE AREA. WATER VAPOR IMAGERY
SHOWS A DISTURBANCE OVER NORTH CENTRAL MEXICO AND THIS FEATURE
SHOULD ARRIVE LATER TONIGHT AND WILL LIKELY HELP TRIGGER
SHRA/TSRA. RAP FCST SOUNDINGS SHOW PW VALUES SURGING TO 1.72 INCHES
WITH A K INDEX OF 39 AT 10Z. THE STRONG CAPPING INVERSION IN
PLACE MAGICALLY DISAPPEARS BETWEEN 07-08Z AND MAYBE THIS IS DUE TO
THE IMPROVING JET DYNAMICS. ALL SHORT TERM GUIDANCE IS BULLISH
WITH RAIN CHANCES OVERNIGHT SO RAISED POPS TO 80 PERCENT OVER THE
CWA. IF THE CAP HOLDS...THE AREA WILL PROBABLY GET JUST A BROKEN
LINE OF WEAK SHOWERS. CAPE/SHEAR LOOK LIMITED SO NOT EXPECTING
MUCH IN THE WAY OF SEVERE WEATHER BUT ONCE THE CAP ERODES...THERE
COULD BE SOME ISOLATED STRONG TO SEVERE STORMS ESPECIALLY TO THE
NE. CONDITIONS SHOULD DRY OUT QUICKLY ON THURSDAY IN THE WAKE OF
THE FRONT WITH SLIGHTLY COOLER TEMPS. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 56 66 44 71 51 / 80 20 0 0 10
HOUSTON (IAH) 62 69 47 72 52 / 80 30 0 0 10
GALVESTON (GLS) 66 68 54 66 60 / 60 60 0 0 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 AM CDT THURSDAY FOR
THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY.
SMALL CRAFT ADVISORY UNTIL 4 AM CDT THURSDAY FOR THE FOLLOWING
ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20
TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 PM CDT WED MAR 23 2016
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 300 PM CDT WED MAR 23 2016
HAVE BEEN MONITORING THE CURRENT FORECAST VERSUS OBSERVATIONS AND
THE LATEST MODEL DATA. STRONG FRONTOGENETIC BAND ANCHORED AT
600-700MB HAS NOW SHIFTED NORTH OF I-90 AS FORECAST WELL BY THE
RAP MODEL GUIDANCE. AS EVENING APPROACHES...A MORE SW-NE ORIENTED
BAND WILL BECOME ESTABLISHED FROM SOUTHEAST MN THROUGH CENTRAL
WI. THIS IS THE BAND CURRENTLY SEEN ON RADAR OVER MN...WHICH WILL
INTENSIFY AND DROP SOUTHEAST. GETTING SOME MIX OF SLEET AND
FREEZING DRIZZLE S-SW OF LA CROSSE PER OBSERVATIONS AND DUAL POL
CC PRODUCT.
VERY GOOD AND CONSISTENT DETERMINISTIC GUIDANCE COMING IN FOR THE
EVOLUTION OF THIS SYSTEM. OVERALL THE HEAVIEST LIQUID AMOUNTS LINE
UP WELL WITH OUR ONGOING FORECAST. THE LATEST WPC GUIDANCE PLACES
1.3 INCHES OF LIQUID IN THE FRONTOGENETIC BAND. SNOW RATIOS WILL
PROBABLY BE A BIG DETERMINISTIC FACTOR IN THE AMOUNT OF
SNOW...WITH 10-11 TO 1 PROBABLY ABOUT RIGHT.
SOUTH OF THE FRONTOGENETIC BAND...LOSS OF ICE ALOFT WILL CAUSE A
FREEZING DRIZZLE ENVIRONMENT. THIS MAY BE AROUND SOME HOURS UNTIL
THE CONVECTIVE SURGE THIS EVENING AND OVERNIGHT...WHERE DEEP ICE
WILL AGAIN ENTER THE AREA. THE WARM LAYER ALOFT IN THE SOUTH
REMAINS WARM ENOUGH FOR COMPLETE MELTING AS WELL AND COLD AIR IS
UNDERCUTTING THIS WARM LAYER LATER TONIGHT. WHILE THE ADVISORY
COVERS SOME OF THIS AREA...WE WILL BE WATCHING THE HIGHWAY 18
CORRIDOR FOR MORE ICING OVERNIGHT...AN ADVISORY MAY BE NEEDED.
TEMPERATURES REMAIN ABOVE FREEZING FOR A PERIOD TONIGHT...SO
ICING SHOULD BE MINIMIZED THERE. THE NEW FORECAST HAS ALSO SLOWED
THE SNOW EXIT ON THURSDAY MORNING...WITH ACCUMULATING SNOW STILL
IN WISCONSIN FOR THE COMMUTE HOURS.
THE ONLY OTHER CONCERN TO SHARE IS THE TREND IN THE LATEST HRRR
GUIDANCE WITH A FURTHER SOUTH /NERN IA-SWRN WI/ SOLUTION TO
CONVECTIVE ACTIVITY THIS EVENING...AND THE DIMINISHING
FRONTOGENETIC SW-NE BAND OVER SERN MN INTO CENTRAL WI. COMPARING
TO HOP WRF SOLUTIONS AND OTHER MESOMODELS...THINKING THE HRRR IS
AN OUTLIER SOLUTION AT THIS TIME.
BOTTOM LINE IS TRAVEL WILL GET PRETTY TREACHEROUS TONIGHT WITH
CONVECTIVE SNOW RATES OF 1-3 INCHES PER HOUR IN FRONTOGENETIC
BAND. INSTABILITY IS ALREADY SEEN IN THE RADAR IMAGERY WITH VERY
SHOWERY LOOKS TO ELEMENTS SOUTH OF THE MAIN SNOW BAND. ALSO SEEING
100 C-G LIGHTNING STRIKES ACROSS NEBRASKA...SO WE COULD BE IN FOR
A THUNDERSNOW TONIGHT. HAVE KEPT THE 10-14 INCH SNOW BAND FROM
SERN MN INTO CENTRAL WI. ICING AND SLEET WILL MIX IN TO THE SOUTH
WITH MAYBE A TENTH OF ICING.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 300 PM CDT WED MAR 23 2016
SIGNALS CONTINUE FOR SATURDAY WITH LIGHT PRECIPITATION EXPECTED
WITH SHORTWAVE ENERGY. HAVE CONTINUED PREVIOUS FORECAST WITHOUT
CHANGES...WITH RAIN SHOWERS LOOKING MORE LIKELY IN THE AFTERNOON
IN WISCONSIN.
MONITORING CONTINUES FOR THE SUNDAY-MONDAY TIME FRAME ON MORE
SIGNIFICANT ENERGY SHIFTING THROUGH THE BROAD LONG WAVE TROUGH
THROUGH THE CENTRAL U.S. BOTH THE 23.00Z AND 23.12Z ECMWF AND
23.12 CANADIAN SUGGEST THIS SHORTWAVE TROUGH ENERGY IS STRONGER
THAN THE GFS SYSTEM OF SOLUTIONS...WITH A SLIGHT NEGATIVE TILT AND
WELL FORMED DEFORMATION PRECIPITATION SHIELD WHICH LOOKS TO BE
SNOW ON THE NORTHWEST SIDE. THIS COULD AFFECT SOUTHWEST OR CENTRAL
WI DEPENDING ON THE TREND. THE PROGRESSIVE PREVIOUS TWO RUNS OF
THE GFS HAVE NO WEATHER FOR THIS TIME FRAME. HAVE CARRIED LOW
RANGE CHANCES FOR PRECIPITATION AT THIS TIME.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 1100 PM CDT WED MAR 23 2016
WINTER STORM IMPACTS KRST/KLSE INTO THU MORNING...WITH IFR/LIFR CIGS
AND VSBYS. EXPECT THE BULK OF THE ACCUMULATING SNOWS TO END BETWEEN
12-15Z THU...WITH GRADUAL IMPROVEMENT IN THE CIGS DURING THE
AFTERNOON/EVENING.
NEXT DEFORMATION REGION QUICKLY DEVELOPING NORTH OF THE SFC LOW LATE
THIS EVENING. SNOW FALLING IN THIS REGION...WITH OBS SHOWING SUB 1SM
VSBYS. EXPECT VSBYS FROM 1/4 TO 1SM FOR MOST OF THE OVERNIGHT.
HOURLY SNOWFALL RATES OF 1-2 INCHES POSSIBLE...WITH ACCUMS BY 12Z
THU FROM 6 TO 8 WET INCHES. SOME THUNDER TO THE SOUTH...AND CAN/T
RULE OUT A CRACK OF THUNDER AT KRST/KLSE...BUT NOT ENOUGH CONFIDENCE
TO ADD TO FORECAST.
WINDS WILL STAY RELATIVELY STRONG AND GUSTY THROUGH THE
OVERNIGHT...BUT LITTLE IF ANY BLOWING/DRIFTING DUE TO THE WET NATURE
OF THE SNOW.
&&
.HYDROLOGY...
ISSUED AT 300 PM CDT WED MAR 23 2016
DUE TO THE EXCESSIVE RAINFALL FROM LAST WEEK...AREA RIVERS
CONTINUE TO RUN HIGHER THAN NORMAL. FLOOD WARNINGS CONTINUE FOR
THE MISSISSIPPI RIVER AT BOTH GUTTENBERG AND MCGREGOR AND THE
WISCONSIN RIVER AT MUSCODA.
SNOW MELT FROM THIS SYSTEM MAY PROLONG ELEVATED LEVELS IN AREA
RIVERS. ONLY THOSE RIVERS NEAR FLOOD STAGE WOULD POSSIBLY RE-ENTER
FLOOD STAGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING UNTIL NOON CDT THURSDAY
FOR WIZ041>044-053.
WINTER STORM WARNING UNTIL NOON CDT THURSDAY FOR WIZ017-029-
032>034.
WINTER WEATHER ADVISORY UNTIL NOON CDT
THURSDAY FOR WIZ054-055.
MN...WINTER STORM WARNING UNTIL NOON CDT THURSDAY
FOR MNZ094>096.
WINTER STORM WARNING UNTIL NOON CDT THURSDAY FOR MNZ079-086>088.
IA...WINTER STORM WARNING UNTIL NOON CDT THURSDAY
FOR IAZ008>010-018-019.
WINTER WEATHER ADVISORY UNTIL NOON CDT
THURSDAY FOR IAZ011.
&&
$$
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...RIECK
HYDROLOGY...BAUMGARDT
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1143 AM EDT THU MAR 24 2016
.SYNOPSIS...
A STATIONARY FRONT WILL REMAIN SOUTH OF LONG ISLAND TODAY AND
THEN MOVE NORTHWARD AS A WARM FRONT TONIGHT. IT MOVES NORTH OF THE
REGION LATE TONIGHT. A COLD FRONT WILL FOLLOW FRIDAY AFTERNOON AND
EVENING. HIGH PRESSURE FROM THE OHIO VALLEY BUILDS IN THEREAFTER
THROUGH THE WEEKEND. LOW PRESSURE MAY IMPACT THE AREA EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST CHALLENGE FOR THE DAY WILL BE THE DEVELOPMENT AND EXTENT
OF STRATUS NORTH OF A STATIONARY FRONT LOCATED ACROSS CENTRAL NJ.
LATEST SAT IMAGERY/OBS SHOW STRATUS EXPANDING ACROSS LI AND
COASTAL CT. DAYTIME HEATING WILL OFFSET SOME OF THE DEVELOPMENT
WITH AREAS FROM NYC AND NORTH AND WEST LIKELY TO SEE MORE SUN.
SOME OF THE HIRES MODELS SUCH AS...RAP...HRRR...AND NARRE HAVE
DIFFERING SOLUTIONS. THE 11Z NARRE HAS DONE FAIRLY WELL WITH THE
COVERAGE AND ACTUALLY BEGINS TO MIX OUT THE STRATUS EVEN ALONG THE
COAST THIS AFTERNOON WITH THE EXCEPTION OF THE TWIN FORKS OF LI.
HOWEVER...THE HRRR EXPANDS THE CLOUD OVER THE ENTIRE FORECAST
AREA THROUGH EARLY AFTERNOON AND THEN STARTS MIXING IT OUT ACROSS
INLAND AREAS. HAVE TAKEN A MIDDLE ROAD APPROACH BASED ON
GRADUALLY INCREASING LOW-LEVEL MOISTURE BENEATH A SHARP LOW-
LEVEL INVERSION....WITH PARTLY SUNNY SKIES FROM NYC NORTH AND
WEST...AND MOSTLY CLOUDY AT THE COAST.
HIGHS COULD ALSO VARY BY SEVERAL DEGREES DEPENDING ON THE AMOUNT
OF CLOUD COVER. FOR THE TIME...HAVE THE UPPER 40S IMMEDIATE
COAST...LOWER 50S TO MID 50S...LI AND CT...AND MID TO UPPER 50S
NYC AND POINTS NORTH AND WEST,
DESPITE THE UPPER LEVEL JET MOVING FARTHER NORTH OF THE REGION
TODAY...WITH RIDGING AT THE MID AND UPPER LEVELS...A MUCH COOLER
ENVIRONMENT WILL BE ENCOMPASSING THE REGION DUE TO A MODIFIED
BOUNDARY LAYER. THE BOUNDARY LAYER WILL HAVE EASTERLY FLOW WITH
LIMITED MIXING HEIGHTS.
A STATIONARY FRONT WILL REMAIN SOUTH OF LONG ISLAND WITH EASTERLY
FLOW DOMINATING. EXPECTING WEATHER TO STAY DRY TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
FOR TONIGHT...WITH THE CONTINUED ENTRAINMENT OF MOISTURE INTO THE
BOUNDARY LAYER AND WITH DRIER AIR ALOFT...THERE WILL BE SOME
POTENTIAL FOR VERY LIGHT RAINFALL OR DRIZZLE THIS EVENING. THIS
WAS HINTED WITHIN SOME MESOSCALE MODELS DEPICTING SOME WEAK
REFLECTIVITY DEVELOPING ACROSS THE REGION.
LATE TONIGHT...THE LOW LEVEL SOUTHWEST JET INCREASES TO 50-60 KT
AT AROUND 900MB. THE FRONT SOUTH OF LONG ISLAND WILL MOVE
NORTHWARD AS A WARM FRONT. THE MIN TEMPERATURES WILL LIKELY BE SET
IN THE EVENING WITH SLIGHTLY RISING TEMPERATURES OVERNIGHT IN
RESPONSE TO INCREASED WARM AIR ADVECTION BEHIND THE WARM FRONT.
THE SOUTHERLY FLOW INCREASES THROUGHOUT THE ATMOSPHERE.
THIS WILL ALLOW FOR RAINFALL TO BECOME MORE INTENSE AND FOR LARGER
RAINDROPS. THE RAIN SHOWERS WILL INCREASE OVERNIGHT INTO FRIDAY.
MUCH OF ANY INSTABILITY IS MOSTLY WEST AND SOUTH OF THE REGION SO
LEFT OUT ANY MENTION OF THUNDERSTORMS. THIS INSTABILITY INCREASES
DURING THE DAY FRIDAY AHEAD OF AN APPROACHING COLD FRONT. THE WARM
AIR ADVECTION WILL BE CONTINUING THROUGH THE DAY. SHOWERS WILL
HAVE SOME EMBEDDED THUNDERSTORMS...BUT WITH MODEL MUCAPE FIELDS IN
DISAGREEMENT WITH ONLY THE NAM SHOWING ANY CAPE ABOVE 100
J/KG...LEFT THE COVERAGE OF THUNDERSTORMS AS ISOLATED.
THE CHANCES FOR SHOWERS DECREASE FRIDAY AFTERNOON FROM WEST TO
EAST. THERE WILL BE SOME TIME WITH THE WINDS SWITCHING TO A MORE
WESTERLY FLOW THAT LATE IN THE DAY...MIXING LENGTHS INCREASE AND
THIS WILL MAKE FOR VERY MILD CONDITIONS. TEMPERATURES ARE FORECAST
TO REBOUND WELL INTO THE 60S AND LOWER 70S FOR A FEW LOCATIONS.
FOR FRIDAY NIGHT...THE ATMOSPHERE CONTINUES TO BECOME DRIER WITH
MORE WESTERLY FLOW. LOW LEVELS WILL HAVE COLD AIR ADVECTION WITH
THE DEVELOPMENT OF MORE NORTHWEST FLOW. HIGH PRESSURE FROM THE
OHIO VALLEY WILL START TO BUILD IN. CLOUDS DECREASE AND WITH A
LIGHTER NORTHWEST FLOW...A LARGE DIURNAL CONTRAST IN TEMPERATURE
WILL BE SET AS LOWS DECREASE TO A RANGE OF UPPER 20S FOR RURAL
INTERIOR LOCATIONS TO 30S FOR MOST LOCATIONS AND LOWER 40S IN NYC.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
DRY CONDITIONS EXPECTED OVER THE WEEKEND AS HIGH PRESSURE BUILDS TO
OUR NORTH. A LOW PRESSURE SYSTEM WILL APPROACH THE AREA SUNDAY
NIGHT...PUSHING A COLD FRONT THROUGH THE AREA ON MONDAY. 00Z ECMWF
AND GFS CONTINUE TO DIFFER ON THE TIMING OF THE FRONT AND DURATION
OF THE PRECIPITATION OF THIS SYSTEM, WITH THE GFS BEING MORE
PROGRESSIVE. AT THIS TIME WILL KEEP PRECIPITATION IN FOR MONDAY.
CANADIAN HIGH BUILDS IN BEHIND THE FRONT AND REMAINS THRU THE MIDDLE
OF NEXT WEEK PRODUCING FAIR AND COOL WEATHER.
TEMPERATURES WILL BE NEAR OR SLIGHTLY ABOVE NORMAL DURING THE LONG
TERM PERIOD WITH HIGH TEMPERATURES IN THE 50S AND LOWS IN THE MID TO
UPPER 30S TO LOW TO MID 40S ACROSS THE NY METRO.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
A FRONTAL BOUNDARY REMAINS SOUTH OF LONG ISLAND TODAY AND THEN
PUSHES NORTH AS WARM FRONT TONIGHT...WITH A COLD FRONT APPROACHING
FRIDAY MORNING.
GUSTY EAST-NORTHEAST WINDS RE-DEVELOP THIS MORNING...WITH 15 TO 20
KT WITH GUSTS TO 25 KT AT KLGA/KBDR. ELSEWHERE 10 TO 15 KT WITH
GUSTS TO 20 KT LIKELY. E/ESE WINDS AND GUSTS SHOULD GRADUALLY WEAKEN
THIS AFTERNOON...THEN SHIFTING S IN WAKE OF WARM FRONT TONIGHT. S
WINDS INCREASE TO 15 TO 20 KT FOR COASTAL TERMINALS LATE TONIGHT.
LLWS LIKELY DEVELOPS TOWARDS MIDNIGHT...AND CONTINUE INTO FRI
MORNING...WITH 50 KT SW FLOW DEVELOPING AT 2KFT.
MVFR STRATUS HAS SHIFTED NORTH...NOW IMPACTING PORTIONS OF THE CITY
TERMINALS AND POINTS EAST. NARRE AND DETERMINISTIC GUIDANCE SUITE
INDICATING STRATUS WILL GRADUALLY LIFT OR SCATTER CIGS TO VFR DURING
THE AFTERNOON...AROUND 17Z-19Z. NOT SURE IF WE EVER BECOME VFR AT
KGON. WE MAY STAY MVFR THROUGH THE DAY.
MVFR STRATUS POTENTIAL SHOULD INCREASE LATE THIS EVENING THROUGH
06Z AHEAD OF WARM FRONT AND THEN POTENTIAL FOR IFR CONDITIONS IN
SHRA LATE TONIGHT AS MOIST AIRMASS MOVES IN WAKE OF WARM FRONT.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: TIMING OF MVFR STRATUS EROSION COULD BE OFF BY
1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
KLGA FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 25 KT LIKELY INTO EARLY
AFTERNOON.
KEWR FCSTER COMMENTS: GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
KHPN FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY
AFTERNOON.
KISP FCSTER COMMENTS: TIMING OF MVFR STRATUS EROSION COULD BE OFF BY
1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
.OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...
.FRIDAY...IFR OR LOWER CONDS POSSIBLE FRIDAY MORNING WITH -SHRA.
LOW PROB FOR SPARSE THUNDERSTORM COVERAGE. S/SW WINDS 10 TO 15 KT
WITH GUSTS TO 20 KT FRIDAY MORNING. LLWS POTENTIAL THREAT
DECREASING FRI MORNING. CONDS IMPROVING TO MVFR THEN VFR FRI
MORNING INTO AFTERNOON. W-NW WINDS G20-25KT POSSIBLE FRIDAY
AFTERNOON IN WAKE OF COLD FRONT.
.FRIDAY NIGHT...BECOMING VFR. NW-NE WINDS G15-20KT POSSIBLE.
.SATURDAY-SUNDAY...VFR.
.SUNDAY NIGHT-MONDAY...MVFR OR LOWER POSSIBLE IN RAIN AND WIND.
&&
.MARINE...
EASTERLY FLOW WILL INCREASE THE FETCH WITH HIGHER WAVE HEIGHTS IN
THE FORECAST FOR EASTERN LONG ISLAND SOUND AND ACROSS THE OCEAN
ZONES. WIND GUSTS WILL ALSO REACH 25 TO 30 KT ACROSS MOST WATERS
EXCEPT FOR NY HARBOR AND THE SOUTH SHORE BAYS...WHERE THESE WILL
BE JUST OCCASIONAL WITH GUSTS CLOSER TO 20 KT. THEREFORE...SCA
REMAINS IN EFFECT THROUGH THE DAY FOR ALL WATERS EXCEPT FOR NY
HARBOR AND SOUTH SHORE BAYS. HOWEVER...DO EXPECT WIND GUSTS TO
DECREASE SOMEWHAT OVER WESTERN LONG ISLAND SOUND THIS AFTERNOON SO
SCA THERE ONLY GOES TO 18Z. TONIGHT AND FRIDAY...WIND GUSTS WILL
BE MORE LIMITED...SO THE SCA CONDITIONS WILL PREVAIL JUST FOR THE
OCEAN ZONES WHERE HIGHER SEAS WILL BE AND MORE MIXING WILL TAKE
PLACE. FOR FRIDAY NIGHT...THERE COULD BE MORE WIDESPREAD SCA
CONDITIONS WITH COLD AIR ADVECTION OCCURRING BEHIND THE COLD
FRONT.
AS HIGH PRESSURE BUILDS ACROSS THE AREA WATERS ON SATURDAY...SEAS
WILL BEGIN TO FALL BELOW SCA LEVELS BY SATURDAY AFTERNOON. SEAS AND
WINDS STAY BELOW SCA LEVELS THROUGH SUNDAY. LOW PRESSURE WILL IMPACT
THE AREA WATERS ON MONDAY AND INTO TUESDAY..WITH SCA LEVELS WINDS
AND SEAS POSSIBLE.
&&
.HYDROLOGY...
TONIGHT THROUGH FRIDAY...RAIN AMOUNTS WILL RANGE BETWEEN A
QUARTER TO A HALF INCH.
NO SIGNIFICANT WIDESPREAD RAINFALL IS EXPECTED FRIDAY NIGHT AND OVER
THE WEEKEND. ADDITIONAL RAINFALL IS POSSIBLE FOR THE BEGINNING OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ330-
340.
SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR ANZ335.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ350-353-355.
&&
$$
UPDATE...DW
AVIATION...BC
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1116 AM EDT THU MAR 24 2016
.SYNOPSIS...
A STATIONARY FRONT WILL REMAIN SOUTH OF LONG ISLAND TODAY AND
THEN MOVE NORTHWARD AS A WARM FRONT TONIGHT. IT MOVES NORTH OF THE
REGION LATE TONIGHT. A COLD FRONT WILL FOLLOW FRIDAY AFTERNOON AND
EVENING. HIGH PRESSURE FROM THE OHIO VALLEY BUILDS IN THEREAFTER
THROUGH THE WEEKEND. LOW PRESSURE MAY IMPACT THE AREA EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST CHALLENGE FOR THE DAY WILL BE THE DEVELOPMENT AND EXTENT
OF STRATUS NORTH OF A STATIONARY FRONT LOCATED ACROSS CENTRAL NJ.
LATEST SAT IMAGERY/OBS SHOW STRATUS EXPANDING ACROSS LI AND
COASTAL CT. DAYTIME HEATING WILL OFFSET SOME OF THE DEVELOPMENT
WITH AREAS FROM NYC AND NORTH AND WEST LIKELY TO SEE MORE SUN.
SOME OF THE HIRES MODELS SUCH AS...RAP...HRRR...AND NARRE HAVE
DIFFERING SOLUTIONS. THE 11Z NARRE HAS DONE FAIRLY WELL WITH THE
COVERAGE AND ACTUALLY BEGINS TO MIX OUT THE STRATUS EVEN ALONG THE
COAST THIS AFTERNOON WITH THE EXCEPTION OF THE TWIN FORKS OF LI.
HOWEVER...THE HRRR EXPANDS THE CLOUD OVER THE ENTIRE FORECAST
AREA THROUGH EARLY AFTERNOON AND THEN STARTS MIXING IT OUT ACROSS
INLAND AREAS. HAVE TAKEN A MIDDLE ROAD APPROACH BASED ON
GRADUALLY INCREASING LOW-LEVEL MOISTURE BENEATH A SHARP LOW-
LEVEL INVERSION....WITH PARTLY SUNNY SKIES FROM NYC NORTH AND
WEST...AND MOSTLY CLOUDY AT THE COAST.
HIGHS COULD ALSO VARY BY SEVERAL DEGREES DEPENDING ON THE AMOUNT
OF CLOUD COVER. FOR THE TIME...HAVE THE UPPER 40S IMMEDIATE
COAST...LOWER 50S TO MID 50S...LI AND CT...AND MID TO UPPER 50S
NYC AND POINTS NORTH AND WEST,
DESPITE THE UPPER LEVEL JET MOVING FARTHER NORTH OF THE REGION
TODAY...WITH RIDGING AT THE MID AND UPPER LEVELS...A MUCH COOLER
ENVIRONMENT WILL BE ENCOMPASSING THE REGION DUE TO A MODIFIED
BOUNDARY LAYER. THE BOUNDARY LAYER WILL HAVE EASTERLY FLOW WITH
LIMITED MIXING HEIGHTS.
A STATIONARY FRONT WILL REMAIN SOUTH OF LONG ISLAND WITH EASTERLY
FLOW DOMINATING. EXPECTING WEATHER TO STAY DRY TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
FOR TONIGHT...WITH THE CONTINUED ENTRAINMENT OF MOISTURE INTO THE
BOUNDARY LAYER AND WITH DRIER AIR ALOFT...THERE WILL BE SOME
POTENTIAL FOR VERY LIGHT RAINFALL OR DRIZZLE THIS EVENING. THIS
WAS HINTED WITHIN SOME MESOSCALE MODELS DEPICTING SOME WEAK
REFLECTIVITY DEVELOPING ACROSS THE REGION.
LATE TONIGHT...THE LOW LEVEL SOUTHWEST JET INCREASES TO 50-60 KT
AT AROUND 900MB. THE FRONT SOUTH OF LONG ISLAND WILL MOVE
NORTHWARD AS A WARM FRONT. THE MIN TEMPERATURES WILL LIKELY BE SET
IN THE EVENING WITH SLIGHTLY RISING TEMPERATURES OVERNIGHT IN
RESPONSE TO INCREASED WARM AIR ADVECTION BEHIND THE WARM FRONT.
THE SOUTHERLY FLOW INCREASES THROUGHOUT THE ATMOSPHERE.
THIS WILL ALLOW FOR RAINFALL TO BECOME MORE INTENSE AND FOR LARGER
RAINDROPS. THE RAIN SHOWERS WILL INCREASE OVERNIGHT INTO FRIDAY.
MUCH OF ANY INSTABILITY IS MOSTLY WEST AND SOUTH OF THE REGION SO
LEFT OUT ANY MENTION OF THUNDERSTORMS. THIS INSTABILITY INCREASES
DURING THE DAY FRIDAY AHEAD OF AN APPROACHING COLD FRONT. THE WARM
AIR ADVECTION WILL BE CONTINUING THROUGH THE DAY. SHOWERS WILL
HAVE SOME EMBEDDED THUNDERSTORMS...BUT WITH MODEL MUCAPE FIELDS IN
DISAGREEMENT WITH ONLY THE NAM SHOWING ANY CAPE ABOVE 100
J/KG...LEFT THE COVERAGE OF THUNDERSTORMS AS ISOLATED.
THE CHANCES FOR SHOWERS DECREASE FRIDAY AFTERNOON FROM WEST TO
EAST. THERE WILL BE SOME TIME WITH THE WINDS SWITCHING TO A MORE
WESTERLY FLOW THAT LATE IN THE DAY...MIXING LENGTHS INCREASE AND
THIS WILL MAKE FOR VERY MILD CONDITIONS. TEMPERATURES ARE FORECAST
TO REBOUND WELL INTO THE 60S AND LOWER 70S FOR A FEW LOCATIONS.
FOR FRIDAY NIGHT...THE ATMOSPHERE CONTINUES TO BECOME DRIER WITH
MORE WESTERLY FLOW. LOW LEVELS WILL HAVE COLD AIR ADVECTION WITH
THE DEVELOPMENT OF MORE NORTHWEST FLOW. HIGH PRESSURE FROM THE
OHIO VALLEY WILL START TO BUILD IN. CLOUDS DECREASE AND WITH A
LIGHTER NORTHWEST FLOW...A LARGE DIURNAL CONTRAST IN TEMPERATURE
WILL BE SET AS LOWS DECREASE TO A RANGE OF UPPER 20S FOR RURAL
INTERIOR LOCATIONS TO 30S FOR MOST LOCATIONS AND LOWER 40S IN NYC.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
DRY CONDITIONS EXPECTED OVER THE WEEKEND AS HIGH PRESSURE BUILDS TO
OUR NORTH. A LOW PRESSURE SYSTEM WILL APPROACH THE AREA SUNDAY
NIGHT...PUSHING A COLD FRONT THROUGH THE AREA ON MONDAY. 00Z ECMWF
AND GFS CONTINUE TO DIFFER ON THE TIMING OF THE FRONT AND DURATION
OF THE PRECIPITATION OF THIS SYSTEM, WITH THE GFS BEING MORE
PROGRESSIVE. AT THIS TIME WILL KEEP PRECIPITATION IN FOR MONDAY.
CANADIAN HIGH BUILDS IN BEHIND THE FRONT AND REMAINS THRU THE MIDDLE
OF NEXT WEEK PRODUCING FAIR AND COOL WEATHER.
TEMPERATURES WILL BE NEAR OR SLIGHTLY ABOVE NORMAL DURING THE LONG
TERM PERIOD WITH HIGH TEMPERATURES IN THE 50S AND LOWS IN THE MID TO
UPPER 30S TO LOW TO MID 40S ACROSS THE NY METRO.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
A BACK DOOR COLD FRONT REMAINS SOUTH OF LONG ISLAND TODAY AND THEN
PUSHES NORTH AS WARM FRONT TONIGHT...WITH A COLD FRONT APPROACHING
FRIDAY MORNING.
MODERATELY STRONG AND GUSTY ENE WINDS SHOULD RE-DEVELOP THIS
MORNING...WITH 15 TO 20 KT WITH GUSTS TO 25 KT POTENTIAL AT
KLGA/KBDR. ELSEWHERE 10 TO 15 KT WITH GUSTS TO 20 KT LIKELY. E/ESE
WINDS AND GUSTS SHOULD GRADUALLY WEAKEN THIS AFTERNOON...THEN
SHIFTING S IN WAKE OF WARM FRONT TONIGHT. S WINDS INCREASE TO 15
TO 20 KT FOR COASTAL TERMINALS LATE TONIGHT. LLWS LIKELY DEVELOPS
TOWARDS MIDNIGHT...AND CONTINUE INTO FRI MORNING...WITH 50 KT SW
FLOW DEVELOPING AT 2KFT.
IFR STRATUS HAS SHIFTED NORTH...NOW IMPACTING KJFK AND KISP. THIS
STRATUS IS FORECAST TO CONTINUE SPREADING NORTHWARD. NARRE AND
DETERMINISTIC GUIDANCE SUITE INDICATING STRATUS DEVELOPMENT ACROSS
THE CITY/COASTAL TERMINALS THROUGH 14Z...THEN GRADUAL LIFT OR
SCATTERING OF CIGS TO VFR DURING THE AFTERNOON. EXPECTATION IS FOR
IFR STRATUS OFFSHORE TO LIFT TO MVFR THROUGH MID MORNING AS IT
WORKS ONSHORE. SO WILL MAINTAIN FORECAST OF MVFR CIGS DEVELOPING
THROUGH 14-15Z AS MOISTURE TRAPS UNDER INVERSION...AND THEN
SCATTERING OR LIFTING TO VFR IN THE AFTERNOON WITH DAYTIME
HEATING.
MVFR STRATUS POTENTIAL SHOULD INCREASE LATE THIS EVENING THROUGH
06Z AHEAD OF WARM FRONT AND THEN POTENTIAL FOR IFR CONDITIONS IN
SHRA LATE TONIGHT AS MOIST AIRMASS MOVES IN WAKE OF WARM FRONT.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: TIMING OF MVFR STRATUS EROSION COULD BE OFF BY
1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
KLGA FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 25 KT LIKELY INTO EARLY
AFTERNOON.
KEWR FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY
AFTERNOON.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY
AFTERNOON.
KHPN FCSTER COMMENTS: TIMING OF MVFR STRATUS DEVELOPMENT AND EROSION
COULD BE OFF BY 1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY
AFTERNOON.
KISP FCSTER COMMENTS: TIMING OF MVFR STRATUS EROSION COULD BE OFF BY
1 TO 2 HOURS. GUSTS TO 20 KT LIKELY INTO EARLY AFTERNOON.
.OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...
.FRIDAY...IFR OR LOWER CONDS POSSIBLE FRIDAY MORNING WITH -SHRA.
LOW PROB FOR SPARSE THUNDERSTORM COVERAGE. S/SW WINDS 10 TO 15 KT
WITH GUSTS TO 20 KT FRIDAY MORNING. LLWS POTENTIAL THREAT
DECREASING FRI MORNING. CONDS IMPROVING TO MVFR THEN VFR FRI
MORNING INTO AFTERNOON. W-NW WINDS G20-25KT POSSIBLE FRIDAY
AFTERNOON IN WAKE OF COLD FRONT.
.FRIDAY NIGHT...BECOMING VFR. NW-NE WINDS G15-20KT POSSIBLE.
.SATURDAY-SUNDAY...VFR.
.SUNDAY NIGHT-MONDAY...MVFR OR LOWER POSSIBLE IN RAIN AND WIND.
&&
.MARINE...
EASTERLY FLOW WILL INCREASE THE FETCH WITH HIGHER WAVE HEIGHTS IN
THE FORECAST FOR EASTERN LONG ISLAND SOUND AND ACROSS THE OCEAN
ZONES. WIND GUSTS WILL ALSO REACH 25 TO 30 KT ACROSS MOST WATERS
EXCEPT FOR NY HARBOR AND THE SOUTH SHORE BAYS...WHERE THESE WILL
BE JUST OCCASIONAL WITH GUSTS CLOSER TO 20 KT. THEREFORE...SCA
REMAINS IN EFFECT THROUGH THE DAY FOR ALL WATERS EXCEPT FOR NY
HARBOR AND SOUTH SHORE BAYS. HOWEVER...DO EXPECT WIND GUSTS TO
DECREASE SOMEWHAT OVER WESTERN LONG ISLAND SOUND THIS AFTERNOON SO
SCA THERE ONLY GOES TO 18Z. TONIGHT AND FRIDAY...WIND GUSTS WILL
BE MORE LIMITED...SO THE SCA CONDITIONS WILL PREVAIL JUST FOR THE
OCEAN ZONES WHERE HIGHER SEAS WILL BE AND MORE MIXING WILL TAKE
PLACE. FOR FRIDAY NIGHT...THERE COULD BE MORE WIDESPREAD SCA
CONDITIONS WITH COLD AIR ADVECTION OCCURRING BEHIND THE COLD
FRONT.
AS HIGH PRESSURE BUILDS ACROSS THE AREA WATERS ON SATURDAY...SEAS
WILL BEGIN TO FALL BELOW SCA LEVELS BY SATURDAY AFTERNOON. SEAS AND
WINDS STAY BELOW SCA LEVELS THROUGH SUNDAY. LOW PRESSURE WILL IMPACT
THE AREA WATERS ON MONDAY AND INTO TUESDAY..WITH SCA LEVELS WINDS
AND SEAS POSSIBLE.
&&
.HYDROLOGY...
TONIGHT THROUGH FRIDAY...RAIN AMOUNTS WILL RANGE BETWEEN A
QUARTER TO A HALF INCH.
NO SIGNIFICANT WIDESPREAD RAINFALL IS EXPECTED FRIDAY NIGHT AND OVER
THE WEEKEND. ADDITIONAL RAINFALL IS POSSIBLE FOR THE BEGINNING OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ330-
340.
SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR ANZ335.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ350-353-355.
&&
$$
UPDATE...DW
AVIATION...BC/NV
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1029 AM EDT THU MAR 24 2016
.Near Term [Rest of Today]...
Although the air mass over our forecast area at 13-14Z was fairly
dry with dewpoints in the 50s (other than along the coast), models
continue to indicate the northward advection of higher dewpoints
through the day today. Coupled with the arrival of some steeper
mid-level lapse rates from the west, and at least some mixed
sunshine today, the ingredients are in place for steady
destabilization - particularly across western parts of the area.
Convection-allowing models have been keen on developing some
showers and storms in the western parts of our area late this
afternoon as the atmosphere destabilizes and warm-air advection
gradually ramps up.
There is currently (14Z) a band of convection stretching from near
Tuscaloosa to near New Orleans, and stretching further SW
offshore. This was making steady progress east, and was generally
not depicted well in many models - even those that initialized
less than 12 hours ago. Recent runs of the HRRR have depicted this
band of convection ahead of the (now-decaying) primary MCS along
the Gulf coast, and those HRRR runs push clusters or lines of
thunderstorms into the western parts of our forecast area around
21Z to 22Z. Whether or not this specific scenario pans out remains
to be seen, but most models do show an increase in convection in
either the late afternoon or early evening. We continue to show
limited PoPs prior to 21Z, with a rapid increase in the western
half of our area between 21-00Z. Some severe wording was added in
those areas as well; given the combination of moderate instability
and shear, some of the storms could be severe from late this
afternoon into this evening.
&&
.Marine...
In general, winds at all of our marine observation sites have been
running near or over the available model guidance. Buoy 42039 to
the south of Panama City has been around 20 knots for a few hours
and recently spiked to 23 knot sustained winds. For that reason,
we have issued a Small Craft Advisory to the west of Apalachicola
until 21Z. That may need to be extended, as some models show
another increase in winds closer to 00Z. Some models do also
indicate a lull in winds today, but given the persistence of
strong winds in the western portions of our coastal waters early
this morning, we issued the advisory.
&&
.Prev Discussion [650 AM EDT]...
.Short Term [Friday night Through Saturday]...
A stalled frontal boundary will be in place across Northeast
Florida out into the Gulf of Mexico. A disturbance moving through
the southern stream flow will lead to showers and thunderstorms
developing along the front and lifting northward through the day.
Model guidance continues to remain split regarding the intensity
of this system on Saturday. There seems to be reasonably good
consensus that there will be rain in the area - it`s more a
question of how much. The GFS continues to be on the stronger side
with rainfall amounts, with the NAM/Euro lighter. Overall, went
with a north-south PoP gradient with the highest values along and
south of I-10. Extensive cloudiness will keep temperatures during
the afternoon in the mid 70s.
.Long Term [Saturday Night Through Thursday]...
With one wave moving east of the region on Saturday evening, the
frontal zone will remain nearly stationary across the southern
portion of the region. Model guidance shows a second southern
stream advancing across the Central Gulf Sunday morning ahead of a
northern stream trough racing across the Central Plains. This
system should have a good deal more forcing to work with - thus
feel this system Sunday into Monday will present the greatest
heavy rainfall threat. The 24/00z Euro seems to have shifted
toward the GFS with a little greater QPF this cycle. As a result,
have increased PoPs for Sunday into the 70-80 percent range with
noticeably higher QPF.
By Sunday night, the trailing northern stream trough will be
moving across the Tennessee River Valley and should be
sufficiently strong to sweep the frontal zone south of the
forecast area by Monday afternoon. Drier air will begin to arrive
on Tuesday, with a stretch of dry conditions lasting through
Wednesday.
Thursday looks to feature a return to active weather as the next
system nears the region. Still a lot of details to be worked out
at long ranges, but it appears as though Thursday looks wet, with
some potential for another round of heavy rainfall.
Throughout the period, temperatures are expected to be above
climatology, especially with respect to overnight lows early in
the period. Some cooler and drier air will arrive Tue-Wed, but
should only return temperatures to climatology - before warming
again ahead of Thursday`s storm system.
.Aviation...
[Through 12Z Friday] A cold front will approach the region today and
slow as it moves over us this evening. VFR conditions are expected
until late in the afternoon with increasing cloudiness at MVFR
levels this evening as the front approaches. MVFR-IFR vsbys will
also be possible with storms ahead of the cold front which will
begin to spread from west to east across the area around 21Z. Winds
from the south will be gusty ahead of the front and may be more
variable and even gustier during stronger storms. Winds will then
shift to the northwest behind the front late in the period.
.Fire Weather...
Hazardous fire weather conditions are not expected through at
least early next week.
.Hydrology...
Three separate periods of rainfall over the next few days will
lead to the potential for river flooding by the end of the weekend
and into next week. While there`s still some uncertainty with
respect to the amounts, it looks at this point like the primary
threat will be more river flooding and less urban flooding. The
most at risk areas for flooding would be our western areas, where
recent rains have stream flows at or just above normal.
Total rainfall from the three systems Thursday evening through
Sunday night could be in the 3 to 5 inch range with isolated
heavier totals possible.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 78 66 77 64 75 / 20 70 60 40 60
Panama City 73 65 72 62 72 / 50 70 40 30 60
Dothan 78 61 74 55 77 / 60 80 40 10 40
Albany 80 64 73 58 75 / 30 80 50 10 40
Valdosta 81 66 77 64 75 / 20 60 70 40 60
Cross City 82 66 79 67 77 / 20 40 50 50 60
Apalachicola 74 67 74 65 72 / 30 60 50 50 70
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AL...NONE.
GM...Small Craft Advisory until 5 PM EDT this afternoon FOR Coastal
waters from Apalachicola to Destin FL out 20 NM-Waters from
Apalachicola to Destin FL from 20 to 60 NM.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...GODSEY
LONG TERM...GODSEY
AVIATION...MOORE
MARINE...LAMERS
FIRE WEATHER...MOORE
HYDROLOGY...GODSEY
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
957 AM EDT THU MAR 24 2016
.UPDATE...
COLD FRONT IS CURRENTLY SITUATED JUST WEST OF THE MISSISSIPPI
RIVER THIS MORNING...WHILE THE SQUALL LINE IS JUST NOW CROSSING
THE RIVER. THE MODELS CONTINUE TO SHIFT THE FILLING LOW PRESSURE
SYSTEM/SHORTWAVE OFF TO THE NORTHEAST.
THERE IS SOME DIFFERENCES BETWEEN THE HI-RES MODELS MODELS THIS
MORNING...WITH THE HRRR A LITTLE FASTER THAN THE REST. THE ARW HAS
BEEN THE MOST CONSISTENT. SCATTERED SHOWERS WILL BE POSSIBLE FOR
THE LATE MORNING/EARLY AFTERNOON IN THE WESTERN PORTION OF THE
CWFA. THE STRONGER ACTIVITY SHOULD BEGIN TO MOVE IN AROUND 18Z.
WITH THE MAIN COLD POOL WELL TO THE NORTH...THE MID LEVEL LAPSE
RATES ARE NOT AS STEEP AS THEY WERE YESTERDAY. HOWEVER...THERE
WILL BE ENOUGH SHEAR AND WITH A 40-50KT LLJ...THE FRONT MAY
PROVIDE ENOUGH LIFT TO PROVIDE ENOUGH POTENTIAL FOR A FEW SEVERE
THUNDERSTORMS LATE THIS AFTERNOON AND EVENING. THE PRIMARY THREATS
SHOULD BE DAMAGING WIND GUSTS AND POSSIBLY SOME LARGE HAIL CLOSEST
TO THE MID LEVEL COLD POOL. AN ISOLATED TORNADO IS STILL
POSSIBLE.
FOR THE UPDATE...HAVE TWEAKED POPS A BIT FOR EARLY THIS MORNING.
THE SHOWERS HAVE BEEN A LITTLE SLOWER TO PROGRESS INTO NW GA.
TEMPS/DEWS LOOKED ALRIGHT SO MADE VERY LITTLE CHANGE.
&&
.PREV DISCUSSION... /ISSUED 726 AM EDT THU MAR 24 2016/
PREV DISCUSSION... /ISSUED /
SHORT TERM /TODAY THROUGH FRIDAY/...
LATEST SURFACE ANALYSIS SHOWS HIGH PRESSURE WELL OFF THE CAROLINA
COAST AND THE MAJOR INFLUENCER OF THE SE WEATHER PATTERN. RETURN
FLOW FROM THIS HIGH IS PRODUCING SOUTHERLY FLOW BOTH AT GROUND
LEVEL AND JUST OFF THE SURFACE ALLOWING FOR AN INITIAL 5K FT DECK
OF CLOUDS TO PUSH INTO PORTIONS OF NORTH GA. SOUTHERLY FLOW ALSO
PLAYING A MAJOR ROLE IN KEEPING TEMPERATURES ELEVATED THIS
OVERNIGHT PERIOD WITH VALUES HOLDING IN THE 50S AND EVEN SOME 60S
STILL OUT THERE.
THE MAIN ISSUE AT LEAST INITIALLY WILL BE THE TIMING OF THE PRE-
FRONTAL ACTIVITY AS WELL AS THE STRENGTH OF THAT ACTIVITY. HI RES
MODELS ARE AGREEING A LITTLE BETTER WITH THE LATEST RUNS IN
BRINGING A LINE OF SHRA TO THE AREA BY 20Z. MUCAPE DURING THIS
TIME PERIOD AND PRIOR TO 00Z LOOKS ONLY ON THE ORDER OF 50 TO 100
J/KG AND PREFER TO KEEP THUNDER OUT OF THE FORECAST FOR THIS FIRST
PHASE.
PHASE 2 HOWEVER WHICH IS FROM 00Z TO 06Z LOOKS TO INCLUDE
MORE ROBUST CONVECTION WITH CAPE VALES NEAR 1000 J/KG PUSHING IN
FROM THE SW AND ROUGHLY ALONG AND SOUTH OF THE I85 CORRIDOR. IN
FACT...ALTHOUGH GREATER SHEAR WILL BE TO THE NORTH....IT IS THIS
AFOREMENTIONED ZONE THAT COULD END UP HAVING THE STRONGER STORMS
GIVEN THE BETTER BALANCE OF INSTABILITY AND SHEAR. OVERALL...THESE
SHEAR VALUES FAVOR DAMAGING WIND GUSTS ALTHOUGH LOW LEVEL HELICITY
IS SUFFICIENT FOR ISOLATED TORNADOES AS WELL. THE LARGE HAIL WILL
BE CONFINED TO THE AREAS WITH THE GREATER MID LEVEL INSTABILITY
WHICH SHOULD BE THE SOUTHERN ZONES BASED ON LATEST MODEL DATA.
THE BIGGEST QUESTION FOR THIS FORECAST CYCLE IS ACTUALLY HOW FAR
SOUTH THE FRONT WILL PROGRESS AND THE TIMING OF ANY CLEARING. GFS
AND ECMWF CONTINUE TO BE THE MOST AGGRESSIVE WITH FRONTAL PASSAGE
BRINGING CLEARING CONDITIONS TO THE NORTH GEORGIA REGION LATE
THURSDAY NIGHT INTO FRIDAY MORNING WHILE THE NAM12 HANGS THE FRONT
UP OVER N GA KEEPING POPS IN MUCH LONGER. FOR NOW WILL GO WITH THE
CONSENSUS OF THE MORE PROGRESSIVE MODELS WITH A GOOD CLEARING
TREND DOWN TO MACON THROUGH FRIDAY MORNING.
DEESE
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
WHILE SHORT TERM FROPA SLOWS AND SETTLES NEAR THE FAR SOUTHEAST
PORTION OF THE AREA FRIDAY NIGHT INTO SATURDAY...WE STAY IN SW
FLOW ALOFT AND ONLY A BRIEF PERIOD WITH QUIET CONDITIONS AS SFC
RIDGE RESULTS IN A RATHER WEAK HYBRID CAD WEDGE. STALLED
BOUNDARY/WEDGE FRONT PROGGED TO LIFT NORTHWARD AS A WARM FRONT
LATE SATURDAY INTO SUNDAY AS GULF MOISTURE OVERRUNNING AND
ISENTROPIC FORCING BRINGS WIDESPREAD SHOWER CHANCES AND TREND OF
THUNDER CHANCES NORTHWARD. MODELS NOW IN BETTER CONSENSUS WITH
FCST EVOLUTION OF DEVELOPING LOW TO TRACK ACROSS THE TN VALLEY
SUNDAY NIGHT THEN PUSH THE ASSOCIATED COLD FRONT SOUTHEASTWARD FOR
MONDAY. AS WITH THE LAST SEVERAL SYSTEMS...WILL NEED TO WATCH FOR
UPSTREAM GULF CONVECTION POTENTIALLY ROBBING US OF MOISTURE
TRANSPORT BUT FOR NOW LOOKS LIKE A GOOD BET FOR LIKELY POPS IN THE
SUNDAY TO SUNDAY NIGHT TIME FRAME. BEST CHANCE FOR THUNDER LOOKS
TO BE SUNDAY AFTERNOON GIVEN FCST CAPE...THOUGH BETTER SHEAR
ENVIRONMENT LOOKS TO BE WITH FROPA LATE SUNDAY NIGHT INTO MONDAY.
DIFFICULT TO SAY WHICH TIME WOULD BE MORE SUPPORTIVE OF STRONGER
CONVECTION AT THE MOMENT SO WILL KEEP MONITORING OF TRENDS.
OTHERWISE THIS SECOND SYSTEM IS FOLLOWED BY A STRONGER RIDGE SO NO
WORRIES OF A LINGERING BOUNDARY TO THE SOUTH FOR TUES/WED AND
SHOULD BE DRY AND PLEASANT. ACTIVE LONGWAVE PATTERN CONTINUES
THOUGH FOR END OF FCST PERIOD WITH MOISTURE ADVECTION AHEAD OF THE NEXT
FRONTAL SYSTEM STARTING TO INFLUENCE THE AREA WED NIGHT INTO
THURS...STARTED CHANCE POPS TREND ACCORDINGLY.
DESPITE THE ACTIVE PERIOD...TEMPS FOR THE MOST PART STAY SLIGHTLY
ABOVE NORMAL THROUGHOUT. SATURDAY IS WARMEST PERIOD WITH HIGHS IN
THE MID 70S ACROSS MAJORITY OF AREA...AND MONDAY NIGHT IS COOLEST
BEHIND AFOREMENTIONED FROPA WITH LOWS IN LOW TO MID 40S BUT STILL
NOT LOW ENOUGH TO RAISE FROST/FREEZE CONCERNS.
BAKER
AVIATION...
06Z UPDATE...
SOUTHERLY FLOW JUST OFF THE SURFACE COMBINED WITH AN
INCREASINGLY MOIST ENVIRONMENT HAS LED TO THE DEVELOPMENT OF VFR
CIGS ACROSS MAINLY THE NORTHERN TAF SITES. CIGS WILL CONTINUE TO
INCREASE IN COVERAGE AREA THROUGH 15Z AND SHOULD BE HERE TO STAY
AS SHRA POTENTIAL INCREASES DURING THE LATE AFTERNOON HOURS.
TIMING OF THE TSRA IS TRICKY AS THERE IS MUCH UNCERTAINTY WITH THE
VARIOUS MODEL SOLUTIONS BUT FOR NOW PUT IT AT 23Z TO 03Z FOR THE
ATL SITES AND SLIGHTLY LATER FOR THE REMAINDER.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON TSRA TIMING.
HIGH ON REMAINING ELEMENTS.
DEESE
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 78 57 73 48 / 50 90 30 10
ATLANTA 76 56 68 49 / 90 100 20 10
BLAIRSVILLE 68 50 65 41 / 90 100 20 5
CARTERSVILLE 72 51 67 41 / 90 100 20 5
COLUMBUS 78 59 73 52 / 70 100 30 10
GAINESVILLE 71 54 69 48 / 90 100 20 10
MACON 80 63 73 51 / 40 80 50 10
ROME 71 49 67 41 / 90 100 10 5
PEACHTREE CITY 76 56 70 44 / 90 100 20 10
VIDALIA 80 66 76 60 / 20 70 60 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
718 AM EDT THU MAR 24 2016
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND OVER THE REGION TODAY. A COLD FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON FRIDAY...LIKELY STALLING JUST SOUTH
AND EAST OF THE REGION THROUGH SATURDAY. UNSETTLED WEATHER IS
EXPECTED SUNDAY...BEFORE A COLD FRONT PUSHES THROUGH THE AREA
MONDAY. DRY HIGH PRESSURE WILL THEN BUILD OVER THE REGION THROUGH
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INCREASED HIGHS 1-2 DEGREES ACROSS INTERIOR SOUTHEAST GEORGIA
WHERE BOTH THE RAP AND H3R ARE SHOWING A FEW MID 80S FOR HIGHS
THIS AFTERNOON. THE REST OF THE FORECAST IS ON TRACK.
UPPER RIDGING THAT HAS BEEN PRESENT ACROSS THE SOUTHEAST U.S. FOR
THE PAST SEVERAL DAYS WILL FINALLY BREAK DOWN TODAY IN RESPONSE
TO A POTENT STORM SYSTEM APPROACHING THE GREAT LAKES REGION.
ATLANTIC HIGH PRESSURE LOOKS TO HOLD ACROSS SOUTHEAST SOUTH
CAROLINA AND SOUTHEAST GEORGIA FOR FOR MUCH OF THE DAY BEFORE
FINALLY RETREATING TONIGHT IN RESPONSE TO AN APPROACHING COLD
FRONT. EXPECT DRY CONDITIONS TO PREVAIL FOR MOST AREAS THROUGH
SUNSET WITH MODELS SHOWING A STRONG SUBSIDENCE INVERSION HOLDING
JUST UNDER 750 HPA. THERE ARE SIGNALS IN BOTH THE SYNOPTIC AND
HIGHER RESOLUTION MESOSCALE MODELS THAT A NORTH-SOUTH ORIENTED
CONVERGENT MOISTURE CHANNEL COULD SETUP JUST OFF THE MIDDLE SOUTH
CAROLINA COAST LATER THIS MORNING. THIS COULD GENERATED ISOLATED
SHOWERS ACROSS THE COASTAL WATERS...SOME OF WHICH COULD MOVE
ONSHORE ACROSS THE MIDDLE/UPPER PORTIONS OF CHARLESTON COUNTY.
UPDRAFTS WITH THESE SHOWERS WILL BE SEVERELY CURTAILED GIVEN THE
PRESENCE OF THE STRONG SUBSIDENCE INVERSION...SO TSTMS APPEAR
UNLIKELY ATTM. WILL CARRY SLIGHT CHANCE POPS FOR CENTRAL AND UPPER
PORTIONS OF CHARLESTON COUNTY AS WELL AS EASTERN BERKELEY COUNTY
FOR TODAY WITH DRY CONDITIONS ELSEWHERE.
TEMPERATURES ARE POISED TO RISE QUICKLY AFTER SUNRISE WITH HIGHS
LIKELY TO WARM INTO THE LOWER 80S ALONG/WEST OF THE I-95
CORRIDOR. A BIT MORE CLOUD COVER AND POSSIBLY A FEW SHOWERS WILL
HELP LIMIT HIGHS TO THE UPPER 70S ACROSS MUCH OF THE CHARLESTON
TRI-COUNTY AREA AWAY FROM THE COAST. HIGHS AT THE BEACHES WILL
ONCE AGAIN BE LIMITED TO THE MID-UPPER 60S...EXCEPT AROUND 70 FOR
SOME GEORGIA BEACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
TONIGHT...A COLD FRONT WILL MOVE STEADILY EAST ACROSS THE DEEP
SOUTH OVERNIGHT AND WILL BE VERY NEAR THE FAR WESTERN ZONES BY
SUNRISE THURSDAY. NO SIGNIFICANT FORCING IS NOTED IN THE VARIOUS
00Z MODEL PROGNOSTICATIONS AND WITH THE POSSIBILITY OF CONVECTION
MOVING ACROSS THE NORTHEASTERN GULF POTENTIALLY DISRUPTING MOISTURE
TRANSPORT AHEAD OF THE FRONT...THE PROSPECTS FOR SIGNIFICANT
RAINFALL WILL REMAIN LOW THROUGH THE NIGHT. WILL CARRY 20-30
PERCENT POPS ACROSS THE FAR WESTERN ZONES BETWEEN MIDNIGHT AND
SUNRISE TO ACCOUNT FOR POSSIBLE SHOWER ACTIVITY ASSOCIATED WITH
THE FRONT ITSELF IMPACTING THOSE AREAS. IT WILL A WARM NIGHT WITH
LOWS ONLY DROPPING INTO THE MID 60 FOR MOST LOCATIONS.
FRIDAY...HIGH PRESSURE WILL RETREAT OVER THE WESTERN ATLANTIC AS A
COLD FRONT SLOWLY SHIFTS OVER THE AREA AND THEN STALLS SOUTH AND
EAST OF THE REGION LATE FRIDAY NIGHT. CHANCES OF SHOWERS AND A FEW
THUNDERSTORMS WILL BE POSSIBLE FOR MOST AREAS AS FROPA OCCURS.
SEVERE WEATHER IS NOT ANTICIPATED GIVEN LIMITED INSTABILITY DURING
THE TIME OF FROPA. DESPITE INCREASING CLOUD COVER AND PRECIP
ACTIVITY...HIGHS SHOULD PEAK IN THE LOW/MID 70S...WARMEST IN
SOUTHEAST GEORGIA.
SATURDAY AND SUNDAY...HIGH PRESSURE WILL ATTEMPT TO WEDGE SOUTHWARD
OVER NORTHERN AREAS ON SATURDAY BEHIND A COLD FRONT THAT STALLS JUST
SOUTH AND EAST OF THE AREA. HOWEVER...THE PATTERN WILL BE SHORT-
LIVED AS LOW PRESSURE BEGINS TO DEVELOP TO THE WEST/SOUTHWEST AND
SLOWLY TRACKS TOWARD THE SOUTHEAST UNITED STATES EARLY NEXT WEEK.
CHANCES OF SHOWERS WILL REMAIN IN THE FORECAST ON SATURDAY. A FEW
THUNDERSTORMS WILL ALSO BE POSSIBLE IN SOUTHEAST GEORGIA WHERE
LIMITED INSTABILITY DEVELOPS. HIGH TEMPS WILL RANGE IN THE UPPER 60S
NORTH...TO LOWER 70S SOUTH. BY SUNDAY...A GREATER CHANCE OF SHOWERS
AND THUNDERSTORMS WILL BE POSSIBLE AS A SERIES OF H5 SHORTWAVES
SHIFT OVER DEEP MOISTURE RESIDING IN THE SOUTHEASTERN UNITED STATES.
TEMPS SHOULD ALSO BE A FEW DEGREES WARMER THAN SATURDAY AS A
SOUTHERLY SFC FLOW RETURNS TO THE AREA.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
A WET PATTERN WILL PERSIST INTO EARLY NEXT WEEK AS A SERIES OF H5
SHORTWAVES PASS OVER THE SOUTHEASTERN UNITED STATES IN ADVANCE OF A
LONGWAVE TROUGH. SHOWER AND THUNDERSTORM COVERAGE SHOULD BE GREATEST
SUNDAY INTO EARLY MONDAY WHEN DEEP MOISTURE CHARACTERIZED BY PWATS
BETWEEN 1.50 TO 1.75 INCHES ADVECTS INTO THE REGION AHEAD OF A COLD
FRONT APPROACHING FROM THE WEST. PRECIP ACTIVITY WILL LIKELY COME TO
AN END ONCE COLD FROPA OCCURS ON MONDAY. DRY AND COOLER HIGH
PRESSURE WILL THEN FOLLOW THE FRONT TUESDAY AND WEDNESDAY...WITH
HIGH TEMPS IN THE LOWER 70S AND OVERNIGHT LOWS IN THE UPPER 40S TO
LOWER 50S WELL INLAND. A WARMING TREND SHOULD THEN OCCUR ON THURSDAY
AS HIGH PRESSURE SLIDES OFFSHORE IN ADVANCE OF THE NEXT LOW PRESSURE
SYSTEM APPROACHING THE SOUTHEASTERN UNITED STATES.
&&
.AVIATION /11Z THURSDAY THROUGH MONDAY/...
VFR. COULD SEE A FEW SHOWERS NEAR THE KCHS TERMINAL LATER THIS
MORNING AS A NORTH- SOUTH ORIENTED MOISTURE CHANNEL SETS UP JUST
OFF THE LOWER SOUTH CAROLINA COAST. ANY ACTIVITY SHOULD REMAIN
EAST OF THE TERMINAL. THE RISK FOR MVFR CIGS WILL INCREASE
OVERNIGHT AS A COLD FRONT DRAWS CLOSER.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS ARE LIKELY FRIDAY
WITH SHOWERS AND THUNDERSTORMS DEVELOPING ALONG A PASSING COLD
FRONT. FLIGHT RESTRICTIONS COULD PERSIST THROUGH THE WEEKEND AND
INTO EARLY NEXT WEEK UNTIL A COLD FRONT PUSHES THROUGH THE REGION
ON MONDAY.
&&
.MARINE...
TONIGHT...SOUTHERLY WIND REGIME WILL REMAIN IN PLACE TODAY AS THE
AREA REMAINS ALONG THE WESTERN FLANKS OF ATLANTIC HIGH PRESSURE.
WILL LIKELY SEE ANOTHER GUSTY SEA BREEZE CIRCULATION IMPACT THE
LAND/SEA INTERFACE AND CHARLESTON HARBOR AGAIN THIS
AFTERNOON...BUT SPEEDS LOOK TO REMAIN A BIT LOWER THAN YESTERDAY.
COULD SEE A FEW HOURS OF 15 KT IN THE CHARLESTON HARBOR WITH 10-15
KT ELSEWHERE. SEAS WILL AVERAGE 2-3 FT.
TONIGHT...LOW-LEVEL JETTING WILL YIELD AN ENHANCED WIND FIELD
ACROSS THE WATERS TONIGHT AS A COLD FRONT APPROACHES FROM THE
WEST. SPEEDS LOOK TO PEAK 15-20 KT FOR MOST LEGS...ALTHOUGH THERE
COULD BE A FEW HOURS OF SPEEDS NEAR 20 KT ACROSS PARTS OF THE
GEORGIA OFFSHORE AND CHARLESTON COUNTY LEGS AFTER MIDNIGHT.
CONDITIONS LOOK MARGINAL FOR A SMALL CRAFT ADVISORY...ESPECIALLY
FOR THE GEORGIA OFFSHORE WATERS...SO FLAGS WILL NOT BE ISSUED WITH
THIS FORECAST CYCLE. SEAS WILL BUILD TO 3-5 FT.
FRIDAY THROUGH TUESDAY...MARGINAL SMALL CRAFT ADVISORY LEVEL
CONDITIONS ARE POSSIBLE IN OFFSHORE GEORGIA WATERS FRIDAY MORNING
BEFORE A COLD FRONT SHIFTS OFFSHORE. ELSEWHERE...WINDS SHOULD PEAK
BETWEEN 15 TO 20 KTS BEYOND 10 NM FROM THE COASTLINE. SEAS WILL ALSO
BUILD UP TO TO 3 TO 5 FT AHEAD OF THE FRONT. BY SATURDAY...A
NORTH/NORTHEAST WIND WILL BE IN PLACE AS HIGH PRESSURE TRIES TO
WEDGE SOUTHWARD BEHIND THE STALLING COLD FRONT. HOWEVER...LOW
PRESSURE IS EXPECTED TO DEVELOP WELL INLAND ON SUNDAY...RESULTING IN
EAST/SOUTHEAST WINDS EARLY NEXT WEEK. WINDS SHOULD PEAK AS HIGH AS
15 TO 20 KTS ON SUNDAY...AND COULD REMAIN ENHANCED THROUGH MONDAY AS
A COLD FRONT PUSHES OFFSHORE LATE. HIGH PRESSURE WILL THEN BUILD
OVER THE WATERS ON THROUGH THE MIDDLE OF NEXT WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
641 AM CDT THU MAR 24 2016
.SHORT TERM...
354 AM CDT
TODAY AND TONIGHT...
STRONG SPRING STORM SYSTEM WORKING ITS WAY THROUGH THE MIDWEST
THIS MORNING. WATER VAPOR IMAGERY INDICATES THE MAIN MID-LEVEL
CIRCULATION WAS CENTERED NEAR KANSAS CITY AT 08Z...WITH A 998 MB
SURFACE LOW JUST NORTHEAST OF KMCI AND A STATIONARY FRONT
EXTENDING NORTHEASTWARD ACROSS NORTHERN IL AND INTO FAR NORTHWEST
INDIANA JUST SOUTH OF LAKE MICHIGAN. 08Z SURFACE OBS DEPICT A 26
DEGREE DIFFERENCE IN TEMPS ACROSS THE CWA...FROM 35 AT WAUKEGAN TO
61 AT RENSSELAER INDIANA. THIS WILL CONTINUE TO BE THE CASE TODAY
AS THE SURFACE LOW TRACKS ALONG THE FRONT...AND EVENTUALLY MOVES
EAST OF THE AREA LATE THIS AFTERNOON.
WFO LOT CWA IS CURRENTLY IN A LULL BETWEEN BAND OF SHOWERS AND
THUNDERSTORMS WHICH LIFTED ACROSS THE AREA OVER THE PAST SEVERAL
HOURS. AREA OF RAIN/EMBEDDED THUNDER OVER EASTERN MISSOURI AND
WEST CENTRAL IL IS EXPECTED TO SPREAD NORTHEAST BACK INTO THE AREA
THIS MORNING HOWEVER...AS DEEP FORCING INCREASES AHEAD OF
APPROACHING UPPER TROUGH AND STRONG MOISTURE TRANSPORT CONTINUES
PARTICULARLY INTO THE SOUTHEASTERN HALF OF THE FORECAST AREA. DRY
SLOT THEN PUSHES IN FROM THE SOUTHWEST MIDDAY/AFTERNOON WHICH
SHOULD CURTAIL PRECIP ACROSS THE SOUTH/SOUTHEAST...WHILE THE
TRAILING PORTION OF THE SYSTEM DEFORMATION ZONE PASSES ACROSS
NORTHERN ILLINOIS. FORECAST SOUNDINGS AND THICKNESS FIELDS
INDICATE THE COLUMN WILL COOL ENOUGH TO CHANGE LINGERING
DEFORMATION BAND PRECIP OVER TO SOME WET SNOW BEFORE ENDING EARLY
THIS EVENING...WITH A BRIEF PERIOD OF MIXED RAIN/SNOW/SLEET DURING
THE TRANSITION. GUIDANCE IS FAIRLY BULLISH WITH POTENTIAL FOR
ACCUMULATING SNOW ACROSS NORTH CENTRAL IL DURING THE LATE
AFTERNOON...AND WHILE SOME ACCUMULATION IS LIKELY...3-4 INCHES
INDICATED BY VARIOUS WRF RUNS MAY BE OVERDONE. EVEN SO...IT DOES
APPEAR THAT SOME ACCUMULATION CAN BE EXPECTED ACROSS FAR NORTH
CENTRAL AND NORTHERN IL WITH PERHAPS AN INCH ON GRASSY OR ELEVATED
SURFACES. PRECIP THEN WINDS DOWN QUICKLY THIS EVENING AS THE
SYSTEM DEPARTS TO THE EAST.
TEMPS TODAY ARE NOT EXPECTED TO STRAY TOO FAR FROM WHERE THEY ARE
NOW WITH THE FRONT BISECTING THE FORECAST AREA. SOME NORTHWARD
MOVEMENT OF THE BOUNDARY IS POSSIBLE ESPECIALLY SOUTH/SOUTHEAST OF
THE CHICAGO METRO AREA...THOUGH CONFIDENCE IS FAIRLY LOW ON EXACT
PLACEMENT. COLDER AIR SURGES IN THIS EVENING ON BLUSTERY NORTH
WINDS AS SKIES CLEAR OUT LATE.
RATZER
&&
.LONG TERM...
354 AM CDT
SATURDAY NIGHT THROUGH THURSDAY...
FRIDAY THROUGH WEDNESDAY...
NICE WEATHER EXPECTED FRIDAY AS UPPER TROUGH FROM OUR CURRENT
MID-WEEK STORM SYSTEM LIFTS AWAY TO THE NORTHEAST AND LOW
AMPLITUDE SHORT WAVE RIDGE DEVELOPS OVERHEAD. SURFACE HIGH
PRESSURE DRIFTS EAST ACROSS THE CWA DURING THE DAY...WITH
SUBSIDENCE AND DRY COLUMN EXPECTED TO PRODUCE A GOOD DEAL OF
SUNSHINE. LIGHT WINDS IN THE VICINITY OF THE RIDGE AXIS THROUGH
EARLY AFTERNOON SHOULD ALLOW FOR TYPICAL SPRING LAKE BREEZE
DEVELOPMENT...THOUGH 925-950 MB MODEL THERMAL FIELDS INDICATE
INLAND AREAS SHOULD BE ABLE TO REACH HIGHS IN THE 48-52 DEGREE
RANGE. WINDS TURN SOUTHEAST BY EVENING...SETTING UP A SEASONABLY
COOL NIGHT AS MID AND HIGH CLOUDS EVENTUALLY INCREASE FROM THE
WEST AHEAD OF THE NEXT UPSTREAM DISTURBANCE.
THAT DISTURBANCE IS ACTUALLY A COUPLE OF INDIVIDUAL SHORT WAVES
WHICH HELP TO AMPLIFY A BROAD UPPER TROUGH ACROSS THE CENTRAL
CONUS THROUGH THE WEEKEND...ONE MOVING ACROSS THE UPPER
MISSISSIPPI VALLEY SATURDAY WHILE THE OTHER DIGS ACROSS THE
CENTRAL/SOUTHERN PLAINS AND EVENTUALLY INDUCES A DEEPENING AREA OF
LOW PRESSURE OVER THE OHIO VALLEY AND LOWER GREAT LAKES REGION BY
LATE SUNDAY AS IT BEGINS TO SWING NORTHEAST FROM THE BASE OF THE
TROUGH. MODEST HEIGHT FALLS DEVELOP INTO THE AREA SATURDAY MORNING
WITH THE APPROACH OF THE NORTHERN WAVE...THOUGH LOW LEVEL MOISTURE
RETURN IS LIMITED TO A NARROW CORRIDOR AHEAD OF THE COLD FRONT
WHICH TRAILS THE SURFACE LOW PRESSURE REFLECTION OVER WISCONSIN.
THUS PRECIP POTENTIAL DURING THE DAY SATURDAY LOOKS TO BE FOCUSED
ACROSS THE WESTERN HALF OF THE CWA AND PRIMARILY MIDDAY INTO THE
AFTERNOON WITH THE ADVANCING COLD FRONT. DESPITE INCREASING MID-
HIGH CLOUD COVER...SOUTH WINDS SHOULD HELP WARM TEMPS INTO THE 50S
OVER MUCH OF THE AREA AND TO AROUND 60 ACROSS THE SOUTH.
WRF...WHICH IS SLOWER WITH THE FRONT...INDICATES A BIT OF A
SOUTHEAST COMPONENT ALONG THE IL LAKESHORE WHICH MAY INDICATE A
VERY WEAK LAKE BREEZE.
FRONT PUSHES EAST ACROSS THE AREA SATURDAY EVENING...THOUGH
LATEST MODEL RUNS REALLY SCALE BACK PRECIP DURING THE EVENING AS
THE STRONGER SYNOPTIC FORCING BECOMES SPLIT TO OUR NORTH AND WELL
TO THE SOUTH. AS THE SOUTHERN LOW BEGINS TO DEVELOP AND DEEPEN
LATE SATURDAY NIGHT...FRONTOGENETIC FORCING ALONG THE SOUTH END OF
THE FRONT INCREASES AND ALLOWS RAIN TO DEVELOP FROM THE SOUTHWEST
INTO PARTS OF THE CWA BY SUNDAY MORNING. MEDIUM-RANGE GUIDANCE
REMAINS A LITTLE DIFFERENT WITH THE EXACT LOW TRACK ACROSS THE
MIDWEST SUNDAY/SUNDAY NIGHT...THOUGH GENERALLY FOCUS PRECIP ACROSS
THE SOUTHEAST HALF TO TWO THIRDS OF THE FORECAST AREA. PARTIAL
THICKNESS FIELDS INDICATE NEARLY ALL OF THE PRECIP WOULD FALL AS
RAIN...THOUGH THE SLIGHTLY FARTHER NORTHWEST TRACK OF THE 12Z
ECMWF WOULD SUPPORT A BRIEF MIX OR CHANGEOVER TO WET SNOW LATE
SUNDAY NIGHT OR EARLY MONDAY BEFORE PRECIP ENDS. CURRENT MODEL
PROGS GENERATE SOME SUBSTANTIAL QPF TOTALS ACROSS THE SOUTHEAST
PORTION OF THE FORECAST AREA THROUGH SUNDAY NIGHT...FROM 0.50
INCHES IN THE FARTHER SOUTHEAST GFS TO 1.25 INCHES IN THE ECMWF.
RISING HEIGHTS THEN DEVELOP INTO THE AREA MONDAY AS THE UPPER
TROUGH PULLS AWAY TO THE EAST...WITH GOOD MODEL CONSENSUS IN
DEVELOPING BROAD UPPER RIDGE ACROSS THE AREA THROUGH MID-WEEK
BEFORE THE NEXT AMPLIFIED UPPER TROUGH APPROACHES. SURFACE HIGH
PRESSURE OVER THE AREA MONDAY INTO TUESDAY WILL LIKELY SUPPORT
LAKE BREEZES BOTH DAYS...WITH TEMPS MODERATING FROM THE MID-40S TO
MID 50S EAST TO WEST MONDAY AND TO THE 55-60 RANGE ON TUESDAY.
SURFACE LOW DEVELOPING TO THE WEST OF THE AREA BY WEDNESDAY WOULD
SUPPORT CONTINUED SOUTH FLOW AND MILD TEMPS MID-WEEK...THOUGH WITH
AN INCREASING CHANCE OF RAIN.
RATZER
&&
.AVIATION...
FOR THE 12Z TAFS...
A FRONTAL BOUNDARY STRETCHES FROM NEAR VYS TO GYY THIS MORNING
WITH NORTHEASTERLY FLOW AND LIFR CIGS NORTH OF THE BOUNDARY AND
SOUTHERLY WINDS AND HIGHER CIGS SOUTH OF THE FRONT. THE FRONT IS
PROGGED TO LIFT SLIGHTLY NORTH TO NEAR MDW BY MID MORNING THEN
SHOULD STALL AND EVENTUALLY START MOVING SOUTH AGAIN. WITH THAT
IN MIND HAVE ALL THE TERMINALS EXCEPT GYY IN NORTHEAST TO NORTH
FLOW THROUGH THE DAY TODAY WITH LIFR CIGS. DEPENDING ON HOW FAR
NORTH THE BOUNDARY GETS...COULD SEE SOME BREAKS IN THE CLOUDS AND
VARIABILITY IN THE WINDS AT MDW...BUT NOT ENOUGH CONFIDENCE TO PIN
ANYTHING DOWN FOR THE TAF.
SHOWERS CONTINUE TO SPREAD NORTH ACROSS NORTHERN ILLINOIS THIS
MORNING AND WILL BE IN PLACE THROUGH MUCH OF THE MORNING INTO
EARLY/MID AFTERNOON AS LOW PRESSURE MOVES ACROSS THE REGION. SOME
VERY MODEST INSTABILITY IS IN PLACE AHEAD OF THE LOW...AS FAR
NORTH AS SOUTHERN WISCONSIN WHICH IS RESULTING IN SOME LIGHTNING
ACTIVITY. FOR NOW IT APPEARS THE AXIS OF HIGHEST INSTABILITY LIES
ALONG AND JUST NORTH OF THE STATE LINE SO WILL KEEP TS OUT OF THE
TAF FOR NOW BUT CERTAINLY CANNOT RULE OUT THE POSSIBILITY TO HAVE
AN EMBEDDED THUNDERSTORM MOVE OVER ONE OF THE TERMINALS. AS THE
LOW PASSES BY MID AFTERNOON...WINDS WILL BACK TO THE NORTH-
NORTHWEST AND BECOME GUSTY. WHILE THIS SHOULD HELP INCREASE CIGS
SLIGHTLY TO HIGHER END IFR...THERE WILL ALSO BE A WINDOW WHEN
MIXED PRECIP OR SNOW IS POSSIBLE. LIGHT ACCUMULATIONS ARE POSSIBLE
FOR RFD WHICH WILL BE DEEPER IN THE COLD AIR. FOR THE CHICAGO
TERMINALS...DRY AIR MOVING IN ALOFT MAY RESULT IN SNOW/DRIZZLE OR
JUST DRIZZLE BEFORE PRECIP ENDS ALTOGETHER THIS EVENING. HIGH
PRESSURE WILL BUILD ACROSS THE AREA ON FRIDAY WHICH SHOULD HELP
IMPROVE CONDITIONS TO VFR AND PROVIDE LIGHT FLOW...ALTHOUGH AN
AFTERNOON LAKE BREEZE IS POSSIBLE.
BMD
&&
.MARINE...
315 AM CDT
MODERATELY STRONG NORTHEASTERLY WINDS OF 30 TO 35 KT ARE IN PLACE
OVER MUCH OF LAKE MICHIGAN EARLY THIS MORNING AHEAD OF AN AREA
OF LOW PRESSURE OVER NORTHERN MISSOURI. WEAKER FLOW IS IN PLACE
ACROSS THE FAR SOUTHERN END OF LAKE MICHIGAN WHERE A FRONTAL
TROUGH IS IN PLACE. THE LOW WILL MOVE JUST SOUTH OF LAKE MICHIGAN
THIS AFTERNOON WITH WINDS BACKING TO THE NORTH AND GALES SPREADING
SOUTH ACROSS THE REMAINDER OF THE LAKE. GALES SHOULD DIMINISH
TONIGHT AND WINDS WILL BECOME LIGHT ON FRIDAY AS A RIDGE AXIS
MOVES OVER THE LAKE. FRESH SOUTHERLY FLOW RESUMES LATE FRIDAY INTO
SATURDAY AS THE RIDGE DEPARTS TO THE EAST ANOTHER FRONT MOVES
ACROSS LAKE MICHIGAN SATURDAY NIGHT INTO SUNDAY TURNING WINDS
NORTH AGAIN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 PM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...4 PM THURSDAY TO 4 AM FRIDAY.
&&
$$
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
[top]
Area Forecast Discussion
National Weather Service Lincoln IL
545 AM CDT THU MAR 24 2016
.SHORT TERM...(Today and tonight)
ISSUED AT 323 AM CDT Thu Mar 24 2016
08z/3am surface analysis shows 997mb low over northern Missouri,
with stationary frontal boundary extending into north-central
Illinois. Based on latest obs, it appears the boundary extends from
near Macomb to just north of Pontiac. To the south of the front in
the warm sector, much of the KILX CWA has current temps in the lower
60s. Meanwhile to the north of the boundary, readings are only in
the lower 40s in Galesburg. A broken line of convection associated
with the approaching low developed across eastern Kansas/western
Missouri last evening...however that activity diminished as it
tracked northeastward and skirted the NW CWA around midnight. Latest
radar imagery shows very little going on across central Illinois:
however, showers are beginning to develop upstream and should spread
into the area over the next couple of hours. HRRR has been quite
persistent showing the showers becoming more widespread along/west
of I-55 after 09z/4am. As the low and accompanying cold front get
closer, showers and a few thunderstorms will develop across the
entire area early this morning. Have therefore carried categorical
PoPs across the board. The low will track to near the Chicago area
by midday, pulling the cold front through central Illinois and
pushing the widespread rain into Indiana at that time. Have
therefore lowered PoPs to just low chance across most of the area
this afternoon. The exception will be northwest of the Illinois
River, where deformation zone rain and snow showers will persist
through the afternoon. High temperatures will be achieved early in
the day, with readings falling steadily this afternoon. By mid
afternoon, temps will range from the upper 30s northwest of the
Illinois River...to the middle 50s near the Indiana border.
.LONG TERM...(Friday through Wednesday)
ISSUED AT 323 AM CDT Thu Mar 24 2016
As low pressure continues to lift into the eastern Great Lakes, a
few rain/snow showers may linger along/north of the I-74 corridor
early this evening before coming to an end before midnight. Skies
will initially be overcast, but will clear from west to east
overnight with lows dropping into the upper 20s and lower 30s. High
pressure will build into the region on Friday, leading to mostly
sunny and cool conditions with highs in the lower to middle 50s.
Once the high shifts off to the east, the next system will begin to
approach from the west over the weekend. Models have been
struggling with this feature for the past several days, and
agreement remains poor with the 00z Mar 24 run. The main issues
have been how much and how quickly an approaching short-wave trough
will amplify. Given the progressive flow pattern, have generally
preferred the weaker and faster solution. As such, will continue to
feature highest rain chances Sunday/Sunday night...followed by a
return to dry weather for Monday and Tuesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 545 AM CDT Thu Mar 24 2016
A large area of showers and isold tsra was tracking across the
forecast area this morning and will affect the cigs and vsbys
for a time as we head into early afternoon. Cigs have been
generally VFR overnight but with rain moving across the area
we expect at least some tempo MVFR cigs and vsbys in the heavier
areas of rain. Once the cold front pushes across the area...forecast
soundings suggest an increase in coverage of MVFR cigs as colder
air wraps into central Illinois this afternoon. Surface winds will
be south to southwest this morning at 12 to 17 kts with occasional
gusts up to 30 kts near the heavier showers. We look for winds to
become more southwest by 17z and then shift into the northwest
around 19z at PIA, 21z at SPI and by 01z at CMI. Once the MVFR
cigs move in behind the cold front, it appears they will linger
thru at least the evening hours, if not longer, based on the
latest forecast soundings.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1045 AM EDT THU MAR 24 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY|/...
ISSUED AT 955 AM EDT THU MAR 24 2016
1345Z UPDATE...CHANGES WERE MADE TO REFLECT THE CURRENT RADAR
MOSAIC WHICH SHOWERS A LITTLE FARTHER WIDESPREAD AND OVER MOST OF
THE FORECAST AREA AS OF THIS HOUR. CONVECTION IS LAGGING
BEHIND...HOWEVER CHANCES WILL REMAIN IN THE FORECAST FOR THIS
AFTERNOON BEFORE AND WHILE THE FRONT MOVES THROUGH THE AREA BY
LATE THIS AFTERNOON. STILL KEEPING 90/100 PERCENT POPS OVER THE
MAJORITY OF THE AREA. SOME MINOR TWEAKS WERE MADE TO HIGH
TEMPERATURES TODAY AS MANY OF THE SITE PROBABLY ALREADY HIT THEIR
HIGH TEMPERATURE MARK EARLIER THIS MORNING AND WILL REMAIN STEADY
OR DECLINE. SITES TO THE NORTHWEST SUCH AS LAF...WHICH MAY SEE
SOME CLEARING LATE THIS AFTERNOON BEHIND THE PRECIP COULD SEE
TEMPERATURE BRIEFLY REBOUND HERE INTO THE LOW 60S. SO LEFT
TEMPERATURE FORECAST AS IS FOR THIS AREA RIGHT NOW. OTHERWISE NO
OTHER MAJOR UPDATES WERE NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS...
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 241500Z TAFS/...
ISSUED AT 1045 AM EDT THU MAR 24 2016
RADAR LOOP AT 1030 AM SHOWS RAIN OVER ALL THE SITES. SOME EMBEDDED
LIGHTNING STRIKES HAVE ALREADY BEEN SEEN IN PARTS OF CENTRAL INDIANA
BUT HAVEN/T HAD LIGHTNING AT ANY OF THE TERMINALS YET. LOOKING
UPSTREAM SEE MORE CONVECTIVE CELLS FORMING IN CENTRAL ILLINOIS IN
THE DRY SLOT AREA MENTIONED BELOW...SO OVERALL FORECAST THINKING
FROM EARLIER IS STILL ON TRACK. FOR THE UPDATE TWEAKED TIMING OF
THUNDER SLIGHTLY AT A COUPLE SITES TO BETTER MATCH HI RES MODELS AND
MADE SOME ADJUSTMENTS TO WINDS WITH STRONG GUSTS OCCURRING QUICKER
AT KBMG BUT BEING LOWER AT OTHER SITES FOR ANOTHER HOUR OR TWO.
DECENT POTENTIAL FOR EMBEDDED LIGHTNING STRIKES TOWARDS MIDDAY INTO
THE AFTERNOON...NEAR THE LEADING EDGE OF THE DRY SLOT AND SURFACE
COLD FRONT AS MID LEVEL LAPSE RATES STEEPEN. BEST POTENTIAL FOR IFR
VISIBILITY RESTRICTIONS APPEAR TO BE IN THIS REGION AS WELL.
PRECIPITATION WILL END BY LATE AFTERNOON WITH THE ARRIVAL OF THE DRY
SLOT.
CEILINGS ARE GRADUALLY LOWERING INTO THE 015-025 RANGE. BRIEFLY
LOWER CEILINGS POSSIBLE IN HEAVIER PRECIPITATION CELLS. CEILINGS
WILL PROBABLY LIFT FOR A TIME LATE THIS AFTERNOON UNDER THE DRY SLOT.
SHOULD SEE SURFACE WIND GUSTS APPROACHING 30 KTS FROM 180-200 DEGREES BY LATE
MORNING AS A 55-60 LOW LEVEL JET CORE MOVES OVERHEAD. WINDS EXPECTED TO VEER
AROUND TO 230-250 DEGREES BY LATE AFTERNOON AFTER FRONTAL PASSAGE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS/CP
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1008 AM EDT THU MAR 24 2016
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY|/...
ISSUED AT 955 AM EDT THU MAR 24 2016
1345Z UPDATE...CHANGES WERE MADE TO REFLECT THE CURRENT RADAR
MOSAIC WHICH SHOWERS A LITTLE FARTHER WIDESPREAD AND OVER MOST OF
THE FORECAST AREA AS OF THIS HOUR. CONVECTION IS LAGGING
BEHIND...HOWEVER CHANCES WILL REMAIN IN THE FORECAST FOR THIS
AFTERNOON BEFORE AND WHILE THE FRONT MOVES THROUGH THE AREA BY
LATE THIS AFTERNOON. STILL KEEPING 90/100 PERCENT POPS OVER THE
MAJORITY OF THE AREA. SOME MINOR TWEAKS WERE MADE TO HIGH
TEMPERATURES TODAY AS MANY OF THE SITE PROBABLY ALREADY HIT THEIR
HIGH TEMPERATURE MARK EARLIER THIS MORNING AND WILL REMAIN STEADY
OR DECLINE. SITES TO THE NORTHWEST SUCH AS LAF...WHICH MAY SEE
SOME CLEARING LATE THIS AFTERNOON BEHIND THE PRECIP COULD SEE
TEMPERATURE BRIEFLY REBOUND HERE INTO THE LOW 60S. SO LEFT
TEMPERATURE FORECAST AS IS FOR THIS AREA RIGHT NOW. OTHERWISE NO
OTHER MAJOR UPDATES WERE NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS...
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 241200Z TAFS/...
ISSUED AT 638 AM EDT THU MAR 24 2016
SOME SHOWER ACTIVITY OVER WEST CENTRAL AND SOUTHWEST INDIANA MAY IMPACT THE
TERMINALS EARLY THIS MORNING. HOWEVER...SHORT TERM MODEL GUIDANCE SUGGESTS
THE MAIN LIFT/MORE WIDESPREAD SHOWER ACTIVITY PROBABLY WON/T MOVE INTO THE
AREA UNTIL THE MID TO LATE MORNING HOURS...ROUGHLY AFTER 241400Z. DECENT
POTENTIAL FOR EMBEDDED LIGHTNING STRIKES TOWARDS MIDDAY INTO THE
AFTERNOON...NEAR THE LEADING EDGE OF THE DRY SLOT AND SURFACE COLD FRONT AS
MID LEVEL LAPSE RATES STEEPEN. BEST POTENTIAL FOR IFR VISIBILITY RESTRICTIONS
APPEAR TO BE IN THIS REGION AS WELL. PRECIPITATION WILL END BY LATE AFTERNOON
WITH THE ARRIVAL OF THE DRY SLOT.
CEILINGS 040-050 EARLY THIS MORNING WILL GRADUALLY LOWER INTO THE 020-025 RANGE
AS THE MAIN PRECIPITATION AREA ARRIVES. BRIEFLY LOWER CEILINGS POSSIBLE IN
HEAVIER PRECIPITATION CELLS. CEILINGS WILL PROBABLY LIFT FOR A TIME LATE THIS
AFTERNOON UNDER THE DRY SLOT.
SHOULD SEE SURFACE WIND GUSTS APPROACHING 30 KTS FROM 180-200 DEGREES BY LATE
MORNING AS A 55-60 LOW LEVEL JET CORE MOVES OVERHEAD. WINDS EXPECTED TO VEER
AROUND TO 230-250 DEGREES BY LATE AFTERNOON AFTER FRONTAL PASSAGE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
657 AM EDT THU MAR 24 2016
.SYNOPSIS...
ISSUED AT 342 AM EDT THU MAR 24 2016
AN UPPER LEVEL DISTURBANCE ACROSS THE CENTRAL UNITED STATES WILL
APPROACH THE AREA TODAY. THIS DISTURBANCE WILL INTERACT WITH A
FRONTAL BOUNDARY ACROSS THE AREA TO PRODUCE WIDESPREAD RAIN
SHOWERS ALONG WITH A FEW THUNDERSTORMS THROUGH THIS AFTERNOON.
GUSTY SOUTH WINDS ARE EXPECTED IN ADVANCE OF THE COLD FRONT WITH
THIS SYSTEM...PARTICULARLY ACROSS FAR NORTHEAST INDIANA AND
NORTHWEST OHIO TODAY. SCATTERED RAIN SHOWERS MAY LINGER INTO THIS
EVENING...BUT DRIER AND COOLER AIR MOVING INTO THE REGION BEHIND A
COLD FRONT WILL GRADUALLY END THE CHANCES OF ADDITIONAL RAIN
SHOWERS OVERNIGHT. CLOUDS WILL DIMINISH ON FRIDAY WITH COOLER
TEMPERATURES. HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE
MID 50S ACROSS NORTHWEST INDIANA AND FAR SOUTHWEST LOWER
MICHIGAN...TO THE MID 60S ACROSS NORTHWEST OHIO. LOW TEMPERATURES
TONIGHT WILL DROP INTO THE LOWER TO MID 30S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM EDT THU MAR 24 2016
STALLED SURFACE BOUNDARY REMAINS SPRAWLED FROM FAR NORTHERN INDIANA
INTO FAR NORTHWEST OHIO THIS MORNING. BROAD ISENTROPIC LIFT/MOISTURE
ADVECTION CONTINUES IN ASSOCIATION WITH THIS BOUNDARY AND HAS
LARGELY BEEN RESPONSIBLE FOR WIDESPREAD RAIN SHOWERS/DRIZZLE ACROSS
PRIMARILY NORTHERN HALF OF THE FORECAST AREA DURING THE OVERNIGHT
HOURS. EXPECTING THAT SOME DIMINISHMENT IN RAIN SHOWER COVERAGE WILL
OCCUR ACROSS THE NORTH DURING THE EARLY-MID MORNING HOURS AS MORE
FAVORED ZONE OF ISENTROPIC ASCENT PER 295K-300K LAYER PROGS LIFTS
NORTHWARD ACROSS CENTRAL LOWER MICHIGAN. RAIN POTENTIAL TO RAMP
UP FROM WEST TO EAST FROM MID MORNING THROUGH THE AFTERNOON AS
POTENT PV ANOMALY OVERSPREADS MID MS VALLEY/SOUTHERN GREAT LAKES
ALONG WITH A CORRESPONDING DOWNSTREAM LOW/MID LEVEL FGEN RESPONSE.
SOME WEAK ELEVATED INSTABILITY IS NOTED PER SPC RUC ANALYSIS AT
06Z ACROSS THE FAR NORTH...BUT PRIMARY INSTABILITY AXIS OF NOTE
FOR LOCAL AREA WILL BE IMMEDIATELY PRECEDING SFC COLD FRONTAL
BOUNDARY THIS AFTERNOON WITH SOME DIFFERENTIAL THERMAL ADVECTION
SETTING UP THIS NARROW CORRIDOR OF INSTABILITY. MAGNITUDE OF
INSTABILITY IS EXPECTING TO BE ON THE MARGINAL SIDE...GENERALLY IN
THE 500-800 J/KG RANGE...BUT A BRIEF POTENTIAL OF NEAR SFC/SFC
BASED INSTABILITY MAY EXIST ACROSS SOUTHEAST HALF OF THE AREA LATE
MORNING-LATE AFTERNOON. THIS WEAK INSTABILITY COMBINED WITH FAIRLY
IMPRESSIVE DEEP LAYER SHEAR MAGNITUDES OF 50-60 KNOTS DOES POSE
SOME CONCERN FOR SMALL LINEAR BOWING SEGMENTS. THIS THREAT REMAINS
HIGHLY CONDITIONAL ON INSTABILITY AND OVERALL SEVERE THREAT
REMAINS LOW. NOT MUCH CHANGE FROM PREVIOUS FORECAST THINKING WITH
ISOLD SEVERE POTENTIAL AT BEST TODAY GIVEN LIMITED
INSTABILITY...WITH ISOLATED STRONGER WIND GUSTS AS THE MAIN
THREAT.
TEMPERATURE FORECAST REMAINS A CHALLENGING ONE IN THE NEAR
TERM...WITH A 20 DEGREE NORTH TO SOUTH TEMPERATURE DIFFERENTIAL
ACROSS THE FORECAST AREA THIS MORNING. SFC BOUNDARY HAS REMAINED
SOMEWHAT STUBBORNLY ANCHORED ACROSS FAR NORTHERN INDIANA...BUT
SHOULD START TO SEE SOME NORTHWARD RETREAT OF THIS BOUNDARY IN THE
09Z-15Z TIMEFRAME. THIS SHOULD PUT BULK OF FORECAST AREA IN WARM
SECTOR...ALBEIT FOR A VERY BRIEF TIME ACROSS THE FAR NORTHWEST AS
SFC REFLECTION REACHES NORTHWEST INDIANA LATE MORNING. OVERALL NOT
MUCH CHANGE TO INHERITED MAX TEMPS...WITH JUST A SLIGHT UPWARD
ADJUSTMENTS INTO THE MID 60S FAR SOUTH CENTRAL/EAST WHERE RESIDENCE
TIME OF WARM SECTOR WILL BE PROLONGED...AND WHERE A MORE DELAYED
PRECIP TIMING IS ANTICIPATED. ANOTHER LOWER END CONCERN TODAY WILL
BE A BRIEF POTENTIAL OF NEAR ADVISORY OR ADVISORY LEVEL SOUTH-
SOUTHWEST WINDS AHEAD OF THIS SYSTEM. SFC REFLECTION SHOULD BE IN A
SLIGHT DEEPENING MODE THIS AFTERNOON WITH AN AXIS OF FAIRLY
STRONG SFC PRESSURE FALLS EXPECTED TO DEVELOP/MIGRATE ACROSS
SOUTHEAST LOWER MICHIGAN. THESE PRESSURE FALLS COMBINED WITH
POTENTIALLY BETTER MIXING WHERE SFC TEMPS ARE EXPECTED TO REACH
THE MID 60S...COULD ALLOW FOR A BRIEF WINDOW OF 35 TO 45 MPH WIND
GUSTS ACROSS THE FAR EAST IN THE 16Z-21Z TIMEFRAME GIVEN STRONG
LOW LEVEL WIND FIELD. HAVE HELD OFF ON ANY WIND ADVISORY AT THIS
TIME GIVEN LOW CONFIDENCE ON DEPTH OF MIXING AND RELATIVELY SHORT
DURATION OF THIS POTENTIAL.
DRY SLOT TO OVERSPREAD THE AREA TONIGHT AS COLDER AIR ADVECTS
SOUTHEASTWARD BEHIND THE FRONT DIMINISHING PRECIP COVERAGE IN THE
EVENING...ALTHOUGH DEFORMATION ZONE MAY PROLONG AT LEAST SCATTERED
SHOWERS ACROSS THE FAR NORTHWEST. ANY CHANGEOVER TO SNOW SHOULD BE
OF MINIMAL PRECIP COVERAGE/INTENSITY AND NO SNOW ACCUMULATION IS
ANTICIPATED AT THIS TIME. END OF THIS PRECIP EVENT COULD TURN OUT
TO BE MORE DRIZZLY IN NATURE TONIGHT...BUT CURRENTLY NOT EXPECTING
ANY SIGNIFICANT IMPACTS FROM POTENTIAL DRIZZLE OR FREEZING DRIZZLE
TONIGHT.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 342 AM EDT THU MAR 24 2016
MUCH MORE BENIGN WEATHER ANTICIPATED FOR FRIDAY AND SATURDAY. ANY
RESIDUAL RN/SN SHOWERS WILL BE QUICKLY CUT OFF BY 12Z AS SHORTWAVE
RIDGE AND ASSOCIATED BUBBLE OF SUBSIDENCE/SURFACE HIGH PRESSURE FOLD
INTO THE GREAT LAKES. SHOULD BE MOSTLY SUNNY BY AFTERNOON AS
NEGATIVE THETA-E ADVECTION FINALLY ERODES THIN LAYER OF MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION IN CAA REGIME. HIGH TEMPS WILL
MAKE A RUN AT UPPER 40S BY LATE AFTERNOON AS WINDS START TO BACK.
LOW 50S MAY EVEN BE POSSIBLE IF MORNING CLOUDS DISSIPATE QUICKER
THAN EXPECTED. MUCH WARMER CONDITIONS FOR SATURDAY AS SW FLOW/WAA
RAMP UP AHEAD OF NEXT WAVE. UPPER 50S TO NEAR 60F POSSIBLE GIVEN
850MB TEMPS AROUND 4C...BUT THE TRADEOFF WILL BE INCREASING HIGH-
BASED CLOUDS ESPECIALLY IN OUR NORTHWEST BY AFTERNOON AS MIDLEVEL
WARM/MOIST AIR ADVECTION INCREASES.
NEXT CHANCE OF RAIN WILL ARRIVE EARLY SUNDAY MORNING AS ANOTHER
VIGOROUS SHORTWAVE RIPPLES THROUGH THE REGION. STILL SOME
INCONSISTENCIES AMONG THE LATEST DETERMINISTIC GUIDANCE TO WORK OUT.
HOWEVER DOES APPEAR TO BE SOME CONSENSUS FOR SURFACE WAVE
DEVELOPMENT ALONG BAROCLINIC ZONE WITH DECENT SHOT OF SOME MODERATE
RAIN AS MIDLEVEL TROUGH TAKES ON AT LEAST A NEUTRAL TILT. BEST
PRECIP CHANCES LOOK TO BE SUNDAY AFTERNOON INTO SUNDAY NIGHT.
THERMAL PROFILES SHOULD BE WARM ENOUGH FOR ALL RAIN...THOUGH IT IS
WORTH NOTING THE ECMWF SOLUTION WOULD SUPPORT THE POSSIBILITY OF A
FEW WET SNOWFLAKES MIXING IN ON BACK EDGE OF EXITING DEFORMATION
BAND. STILL PLENTY OF TIME TO WATCH THIS EVENT AND SUSPECT THERE
WILL BE CHANGES SINCE PARENT JET ENERGY IS STILL OVER THE NORTH
PACIFIC. QUIET WEATHER THEREAFTER AS SPRAWLING MID/UPPER RIDGE AND
SURFACE HIGH MOVE OVER THE REGION. COOL AT FIRST BUT SHOULD WARM UP
AGAIN BY MIDWEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 631 AM EDT THU MAR 24 2016
LATEST SURFACE OBSERVATIONS ARE BEGINNING TO INDICATE A NORTHWARD
ADVANCEMENT OF STALLED FRONTAL BOUNDARY ACROSS NORTHERN INDIANA
EARLY THIS MORNING. CANNOT RULE OUT IFR CIGS OVER NEXT FEW HOURS
BUT IT APPEARS GREATER POTENTIAL OF ADDITIONAL IFR CIGS AT KSBN
SHOULD HOLD OFF UNTIL MIDDAY IN ASSOCIATION WITH GREATER RAIN
POTENTIAL AND APPROACH OF SFC REFLECTION. WITH SFC BOUNDARY HAVING
LIFTED NORTH OF KFWA...VFR OR HIGHER END MVFR CONDITIONS SHOULD
PERSIST THROUGH MIDDAY WITH POTENTIAL OF FUEL ALTERNATE CRITERIA
LIKELY HOLDING OFF UNTIL THIS AFTERNOON IN ASSOCIATION WITH
GREATER RAINFALL THREAT. IN TERMS OF PRECIP POTENTIAL...A BRIEF
LULL WILL CONTINUE THROUGH MID MORNING BUT A VIGOROUS UPPER LEVEL
WAVE AND DEEPER MOISTURE PROFILES WILL SUPPORT RAIN OVERSPREADING
TERMINALS IN THE 16Z-20Z TIMEFRAME. SOME ISO-SCT THUNDER IS
POSSIBLE...PARTICULARLY AT KFWA WHERE SFC BASED INSTABILITY SHOULD
BE A BIT MORE IMPRESSIVE. HOWEVER AT THIS FORECAST DISTANCE WILL
MAINTAIN JUST A VCTS MENTION AT KFWA WITH LINGERING UNCERTAINTY IN
INSTABILITY MAGNITUDE. WINDS TO SHIFT NORTHWEST TONIGHT BEHIND THE
COLD FRONT WITH SOME LINGERING SCATTERED LIGHT RAIN SHOWERS/PATCHY
DRIZZLE THIS EVENING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING FROM 8 PM THIS EVENING TO 5 AM EDT FRIDAY FOR
LMZ043-046.
&&
$$
SYNOPSIS...MARSILI
SHORT TERM...MARSILI
LONG TERM...AGD
AVIATION...MARSILI
VISIT US AT WW.WEATHER.GOV/IWX
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
638 AM EDT THU MAR 24 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /TODAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR THE 241200Z TAFS/...
ISSUED AT 638 AM EDT THU MAR 24 2016
SOME SHOWER ACTIVITY OVER WEST CENTRAL AND SOUTHWEST INDIANA MAY IMPACT THE
TERMINALS EARLY THIS MORNING. HOWEVER...SHORT TERM MODEL GUIDANCE SUGGESTS
THE MAIN LIFT/MORE WIDESPREAD SHOWER ACTIVITY PROBABLY WON/T MOVE INTO THE
AREA UNTIL THE MID TO LATE MORNING HOURS...ROUGHLY AFTER 241400Z. DECENT
POTENTIAL FOR EMBEDDED LIGHTNING STRIKES TOWARDS MIDDAY INTO THE
AFTERNOON...NEAR THE LEADING EDGE OF THE DRY SLOT AND SURFACE COLD FRONT AS
MID LEVEL LAPSE RATES STEEPEN. BEST POTENTIAL FOR IFR VISIBILITY RESTRICTIONS
APPEAR TO BE IN THIS REGION AS WELL. PRECIPITATION WILL END BY LATE AFTERNOON
WITH THE ARRIVAL OF THE DRY SLOT.
CEILINGS 040-050 EARLY THIS MORNING WILL GRADUALLY LOWER INTO THE 020-025 RANGE
AS THE MAIN PRECIPITATION AREA ARRIVES. BRIEFLY LOWER CEILINGS POSSIBLE IN
HEAVIER PRECIPITATION CELLS. CEILINGS WILL PROBABLY LIFT FOR A TIME LATE THIS
AFTERNOON UNDER THE DRY SLOT.
SHOULD SEE SURFACE WIND GUSTS APPROACHING 30 KTS FROM 180-200 DEGREES BY LATE
MORNING AS A 55-60 LOW LEVEL JET CORE MOVES OVERHEAD. WINDS EXPECTED TO VEER
AROUND TO 230-250 DEGREES BY LATE AFTERNOON AFTER FRONTAL PASSAGE.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...JAS
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
636 AM CDT THU MAR 24 2016
.UPDATE...
Issued at 636 AM CDT THU MAR 24 2016
Will probably let the wind advisory expire at 7 AM this morning.
Latest model guidance progs the pressure gradient to relax through
the morning and winds are currently below advisory levels. So
while northwest winds will remain gusty to around 30 MPH, think
the winds are at their strongest now and should gradually weaken
through the day.
The wrap around snow showers continue to make steady progress east
with the upper deformation zone. Think all of the precip should
exit the forecast around 10 am with only minor accumulations.
&&
.SHORT TERM...(Today and Tonight)
Issued at 337 AM CDT THU MAR 24 2016
0730Z satellite imagery shows the upper low over the forecast area
with light rain and snow gradually expanding over north central KS.
The surface low has moved into northwest MO based on objective
analysis.
The progress of the upper closed low has been a little slower than
previously expected. As a result, the winds have been slower to
increase in speed, although strong northwest winds are noted just
west of the forecast area. Think winds are still going to trend
stronger through the morning as models maintain a strong pressure
gradient over the area. But the winds may not be as strong as
previously expected. Plan to continue to wind advisory through 12Z
to monitor trends but at this point think the advisory may be
allowed to expire.
Models are in agreement that the upper low will move east of the
forecast area by late morning and should take the light precip with
it as much of the forcing is mainly from deformation within the
upper trough. Because of this have held onto some POPs across
northeast. Once the wave passes east, dry air advection in the low
levels should allow for the low clouds to clear out with skies
becoming mostly sunny during the afternoon. With some cold air
advection through the day and cloud cover initially, highs look to
only be in the upper 40s and around 50. If the sun breaks out a
little sooner, highs may be a degree or two warmer. By tonight, weak
surface ridging is progged to move across the area with only some
thin high clouds. This should allow winds to become light and
variable helping the boundary layer to radiate out. With this in
mind, have lows in the in the mid and upper 20s.
.LONG TERM...(Friday through Wednesday)
Issued at 337 AM CDT THU MAR 24 2016
Conditions on Friday will still be favorable for elevated fire
weather concerns mainly along and southwest of a line from Concordia
to Manhattan to Emporia line. No headlines are needed at this time
due to conditions likely to remain under criteria with winds gusting
to less than 25 mph from the south/southwest and RH values being
probably in the mid 20s. With a relatively low amplitude trough
advecting into the Northern Plains, it doesn`t appear that wind and
thermal fields will support conditions that could cause a Red Flag
Warning at this time. Confidence in this is on the medium end right
now as it does appear that a LLJ will be just to the west of the
area over East Central KS. As a shortwave deepens over the Northern
Plains, a weak cold front does get pushed into the region Friday
evening and stalls out over northeast KS. Meanwhile a more
amplified southern stream shortwave digs into the Central and
Southern Rockies helping to draw in more gulf moisture return to the
region. With the previously mentioned boundary in place, there
should be enough lift to see chance end POPs over a majority of the
weekend and especially on Sunday. Varying model solutions would
suggest more precip if the EC and NAM verify. However, if the GFS,
which is slightly faster than the EC and not as aggressive with the
deepening of the trough, verifies then it stands to reason precip
amounts will be on the lighter side and come to an end early on
Sunday. Most precip should be in the form of rain especially south
of I-70, but there could be enough cooling with slightly enough cold
air advection to see at least a rain/snow mix north of I-70.
A potentially more interesting system enters the picture on
Wednesday time frame as the next longwave trough becomes highly
amplified and deepens over the Central Rockies. Wind and thermal
fields look fairly impressive once again. While an impressive jet
streak advects over the region late Wednesday with 0-6 bulk shear of
around 90kts and steep mid level lapse rates in place, a fairly
strong EML may be in place. It is possible that with enough cooling
aloft that this cap could be degraded throughout time. Moisture
return will be a big question too as to just how much will actually
advect into the region before the trough pushes through. Mid 50
dewpoints with a strong dryline may just be enough though for this
time of year to aid in storm development. Something to watch over
the next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday Morning)
Issued at 603 AM CDT THU MAR 24 2016
There may be a brief period of IFR VSBY as snow showers move
through the terminals. But for the most part I expect conditions
to remain MVFR with a RASN mix changing to -SN at TOP and FOE.
The clouds will be slower to scatter out once the precip comes to
an end and have timed the clearing based on the NAM/GFS. For some
reason the RAP is slowing down with the clearing and I`m not ready
to buy into with dry low level air moving in behind the system.
VFR conditions should prevail by the early afternoon and through
the night tonight.
&&
.TOP Watches/Warnings/Advisories...
Wind Advisory until 7 AM CDT this morning for KSZ008>012-020>024-
026-034>040-054>056-058-059.
&&
$$
UPDATE...Wolters
SHORT TERM...Wolters
LONG TERM...Drake
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS GOODLAND KS
522 AM MDT THU MAR 24 2016
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 309 AM MDT THU MAR 24 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS CLOSED
UPPER LOW CENTERED OVER NORTHEAST KS...WITH SHORTWAVE RIDGING
BUILDING ACROSS THE CENTRAL ROCKIES TOWARD THE NORTHERN PLAINS ON
THE BACK SIDE OF THIS SYSTEM. THERE ARE STILL A FEW WEAK PLUMES OF
DEEPER MOISTURE ROTATING AROUND THE BACK SIDE OF THIS SYSTEM JUST
EAST OF OUR CWA. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS
EASTERN COLORADO WITH STRONG SURFACE LOW PRESSURE ACROSS NORTHERN
MISSOURI. TIGHT SURFACE GRADIENT BETWEEN THESE FEATURES IS STILL IN
PLACE ACROSS THE EASTERN 2/3 OF OUR CWA AND IS SLOWLY RETREATING
EASTWARD.
TODAY-TONIGHT...UPPER LEVEL SHORTWAVE TROUGH TRANSITION ACROSS OUR
CWA WITHIN NW FLOW ALOFT WITH WEAK LEE TROUGH BEGINNING TO REDEVELOP
BY LATE THIS AFTERNOON. DRY CONDITIONS ARE EXPECTED WITH MAIN
FORECAST CHALLENGE BEING IMPACTS OF SNOW PACK ON HIGHS/LOWS. GROUND
TEMPERATURES ARE WARM ENOUGH STILL THAT MELTING SHOULD OCCUR FAIRLY
QUICKLY AFTER SUNRISE. POTENTIAL EXISTS FOR HIGHS TO REACH THE 50S
TODAY...HOWEVER LOCATIONS IN OUR NORTH/NORTHWEST MAY STRUGGLE TO
REACH THE LOW 40S IF SNOW PACK LIMITS DIURNAL HEATING. DEEPEST SNOW
PACK IS IN YUMA COUNTY AND THIS IS WHERE I HAVE LEAST CONFIDENCE IN
HIGHS TODAY. LOWS TONIGHT SHOULD DROP FAIRLY QUICKLY...HOWEVER LEE
TROUGH BEGINS TO DEEPEN AS ANOTHER FRONT APPROACHES THE REGION WITH
INCREASING BL WINDS. I LEANED LOW TEMP FORECAST TOWARDS 2M GUIDANCE
(WARMER BLENDS) AS MIXING MAY PREVENT BETTER RADIATIONAL COOLING.
FRIDAY-SATURDAY NIGHT...THE NEXT UPPER LEVEL TROUGH MOVES INTO THE
PLAINS WITH TWO SPLITS OCCURRING FRIDAY AND A FRONTAL PASSAGE DURING
THE DAY FRIDAY OR FRIDAY NIGHT. CONFIDENCE IS NOT PARTICULARLY HIGH
DUE TO VARIANCES IN HOW MODELS SHOW FRONTAL TIMING AND MOISTURE
RETURN BETWEEN THESE SPLIT SHORTWAVE TROUGHS. WHERE PRECIP OCCURS IT
APPEARS THAT TEMP/MOISTURE PROFILES SHOULD SUPPORT MAINLY A SNOW
EVENT. BEST CHANCE FOR PRECIP APPEARS TO BE WHEN THE SOUTHERN
SHORTWAVE ROTATES TROUGH THE PLAINS (LIKELY CENTERED SOUTH OF OUR
FORECAST AREA).
00Z NAM WAS THE STRONGEST ON THIS FEATURE WITH A CLOSED H7 CENTER
PASSING NEAR OUR CWA...HOWEVER 06Z TRACK IS FURTHER SOUTH AND
SLIGHTLY MORE PROGRESSIVE. LATEST ECMWF SHOWS THE H7 LOW CLOSING
OFF FURTHER SOUTHEAST AND DEEPENING OVER EASTERN KS...AND THE GFS
ONLY SHOWS A WEAK OPEN WAVE AT H5/H7. QUITE A BIT OF
VARIANCE...WHICH LOWERS CONFIDENCE IN POTENTIAL IMPACTS.
STRONGEST OVERLAPPING PRECIP SIGNAL IS IN OUR SOUTHERN CWA LATE
FRIDAY NIGHT THROUGH SATURDAY MORNING REGARDLESS OF WHICH MODEL WE
CHOOSE...SO I KEPT CHANCE POPS IN THIS AREA. CONSENSUS FAVORS SNOW
ACCUMULATIONS GENERALLY 1-2" (ASSUMING MAINLY SNOW DURING THE
EVENT). WILL NEED TO CONTINUE MONITORING TRENDS.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 309 AM MDT THU MAR 24 2016
SUNDAY THROUGH TUESDAY WILL BE DRY WITH WARMING TEMPERATURES AS AN
UPPER RIDGE MOVES OVER THE CENTRAL HIGH PLAINS. SURFACE HIGH
PRESSURE MOVES INTO THE SOUTHERN PLAINS AS A LEE TROUGH BEGINS TO
DEEPEN ALONG THE FRONT RANGE MONDAY NIGHT AHEAD OF THE NEXT MAIN
UPPER LOW THAT MOVES INTO THE CENTRAL NEVADA. HIGH TEMPERATURES IN
THE 50S ON SUNDAY WILL WARM INTO THE 70S BY TUESDAY. THE INITIAL
SHORT WAVE TROUGH LIFTS OUT OF THE UPPER LOW ACROSS NORTHEAST
COLORADO AND INTO WESTERN NORTH DAKOTA AND WESTERN NEBRASKA BY MID
DAY WEDNESDAY ALONG WITH A COINCIDENT SURFACE LOW CENTER. THERE IS A
POSSIBILITY OF SHOWERS AND THUNDERSTORMS DEVELOPING OVER THE FAR
EASTERN SECTIONS OF THE FORECAST AREA TUESDAY EVENING INTO EARLY
WEDNESDAY AHEAD OF THE SURFACE THROUGH THAT MOVES EASTWARD.
FROM WEDNESDAY THROUGH THURSDAY MODELS BECOME MORE DIVERGENT ON HOW
THE COMBINATION OF THE UPPER LOW OVER THE WEST AND THE LOW LIFTING
INTO THE NORTHERN PLAINS IS HANDLED. THE GFS TENDS TO SEPARATE
THESE FEATURES MORE WITH THE LOW LIFTING INTO THE NORTHERN PLAINS
MAKING BETTER PROGRESS TOWARDS THE GREAT LAKES REGION THAN THE ECMWF
THAT TENDS TO KEEP THE FEATURES LINKED INTO A SINGLE ELONGATED
TROUGH THAT EXTENDS FROM THE NORTHERN HIGH PLAINS TO OFF THE COAST
OF SOUTHERN CALIFORNIA. EITHER WAY IT APPEARS TEMPERATURES WILL
COOL ACROSS THE CENTRAL HIGH PLAINS REGION WEDNESDAY AND THURSDAY AS
THERE WILL BE A COLD FRONT THAT MOVES ACROSS THE REGION WEDNESDAY
NIGHT WITH A CHANCE OF LIGHT RAIN SHOWERS SPREADING ACROSS THE AREA
...CHANGING TO LIGHT SNOW WEDNESDAY NIGHT...AND BACK TO RAIN ON
THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 522 AM MDT THU MAR 24 2016
VFR CONDITIONS SHOULD CONTINUE THROUGH THE TAF PERIOD...WITH
INCREASING 10-25KFT CLOUDS AFTER 00Z. THERE HAVE BEEN A FEW
PATCHES OF 1500-3000KFT STRATUS...HOWEVER THIS HAS BEEN ISOLATED
AND SHOWING A DECREASING TREND ON SATELLITE (MATCHING SHORT RANGE
GUIDANCE. AS A RESULT THIS IS NOT LIKELY TO IMPACT EITHER KGLD OR
KMCK TERMINAL THIS MORNING. GUSTY WINDS WILL DECREASE THIS
MORNING AS HIGH PRESSURE MOVES EAST OVER BOTH KGLD AND KMCK
TERMINALS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...DR
AREA FORECAST DISCUSSION
National Weather Service Topeka KS
603 AM CDT THU MAR 24 2016
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 337 AM CDT THU MAR 24 2016
0730Z satellite imagery shows the upper low over the forecast area
with light rain and snow gradually expanding over north central KS.
The surface low has moved into northwest MO based on objective
analysis.
The progress of the upper closed low has been a little slower than
previously expected. As a result, the winds have been slower to
increase in speed, although strong northwest winds are noted just
west of the forecast area. Think winds are still going to trend
stronger through the morning as models maintain a strong pressure
gradient over the area. But the winds may not be as strong as
previously expected. Plan to continue to wind advisory through 12Z
to monitor trends but at this point think the advisory may be
allowed to expire.
Models are in agreement that the upper low will move east of the
forecast area by late morning and should take the light precip with
it as much of the forcing is mainly from deformation within the
upper trough. Because of this have held onto some POPs across
northeast. Once the wave passes east, dry air advection in the low
levels should allow for the low clouds to clear out with skies
becoming mostly sunny during the afternoon. With some cold air
advection through the day and cloud cover initially, highs look to
only be in the upper 40s and around 50. If the sun breaks out a
little sooner, highs may be a degree or two warmer. By tonight, weak
surface ridging is progged to move across the area with only some
thin high clouds. This should allow winds to become light and
variable helping the boundary layer to radiate out. With this in
mind, have lows in the in the mid and upper 20s.
.LONG TERM...(Friday through Wednesday)
Issued at 337 AM CDT THU MAR 24 2016
Conditions on Friday will still be favorable for elevated fire
weather concerns mainly along and southwest of a line from Concordia
to Manhattan to Emporia line. No headlines are needed at this time
due to conditions likely to remain under criteria with winds gusting
to less than 25 mph from the south/southwest and RH values being
probably in the mid 20s. With a relatively low amplitude trough
advecting into the Northern Plains, it doesn`t appear that wind and
thermal fields will support conditions that could cause a Red Flag
Warning at this time. Confidence in this is on the medium end right
now as it does appear that a LLJ will be just to the west of the
area over East Central KS. As a shortwave deepens over the Northern
Plains, a weak cold front does get pushed into the region Friday
evening and stalls out over northeast KS. Meanwhile a more
amplified southern stream shortwave digs into the Central and
Southern Rockies helping to draw in more gulf moisture return to the
region. With the previously mentioned boundary in place, there
should be enough lift to see chance end POPs over a majority of the
weekend and especially on Sunday. Varying model solutions would
suggest more precip if the EC and NAM verify. However, if the GFS,
which is slightly faster than the EC and not as aggressive with the
deepening of the trough, verifies then it stands to reason precip
amounts will be on the lighter side and come to an end early on
Sunday. Most precip should be in the form of rain especially south
of I-70, but there could be enough cooling with slightly enough cold
air advection to see at least a rain/snow mix north of I-70.
A potentially more interesting system enters the picture on
Wednesday time frame as the next longwave trough becomes highly
amplified and deepens over the Central Rockies. Wind and thermal
fields look fairly impressive once again. While an impressive jet
streak advects over the region late Wednesday with 0-6 bulk shear of
around 90kts and steep mid level lapse rates in place, a fairly
strong EML may be in place. It is possible that with enough cooling
aloft that this cap could be degraded throughout time. Moisture
return will be a big question too as to just how much will actually
advect into the region before the trough pushes through. Mid 50
dewpoints with a strong dryline may just be enough though for this
time of year to aid in storm development. Something to watch over
the next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday Morning)
Issued at 603 AM CDT THU MAR 24 2016
There may be a brief period of IFR VSBY as snow showers move
through the terminals. But for the most part I expect conditions
to remain MVFR with a RASN mix changing to -SN at TOP and FOE.
The clouds will be slower to scatter out once the precip comes to
an end and have timed the clearing based on the NAM/GFS. For some
reason the RAP is slowing down with the clearing and I`m not ready
to buy into with dry low level air moving in behind the system.
VFR conditions should prevail by the early afternoon and through
the night tonight.
&&
.TOP Watches/Warnings/Advisories...
Wind Advisory until 7 AM CDT this morning for KSZ008>012-020>024-
026-034>040-054>056-058-059.
&&
$$
SHORT TERM...Wolters
LONG TERM...Drake
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1019 AM EDT THU MAR 24 2016
.SYNOPSIS...
HIGH PRESSURE WILL RETREAT TO THE NORTH OF THE AREA TODAY. LOW
PRESSURE WILL PASS ACROSS MAINE FRIDAY AND WILL MOVE INTO THE
CANADIAN MARITIMES FRIDAY NIGHT. HIGH PRESSURE WILL BUILD INTO
NORTHERN NEW ENGLAND SATURDAY AND WILL MOVE SLOWLY EAST OF THE
REGION SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1007 AM UPDATE...ADJUSTED THE HRLY TEMPS TO FIT THE LATEST
CONDITIONS AS WELL AS ADJUSTMENTS TO THE QPF AND SNOW. 13Z SFC
ANALYSIS SHOWED DOUBLE BARREL HIGH PRES OVER THE REGION W/AN
INVERTED TROF NOSING UP INTO SW MAINE. THERE WAS SOME DECENT LLVL
CONVERGENCE SHOWING UP PER THE WIND FIELD. SOME LIGHT SNOW WAS
OCCURRING IN THE VICINITY OF THIS TROF W/FREYBERG MAINE(KIZG)
REPORTING SNOW. MRMS RADAR INDICATED SNOW EXPANDING FURTHER E
TOWARD THE COASTAL REGION AND THIS WAS PICKED UP WELL BY THE
LATEST RUN OF THE HRRR 3KM AND NAM12. ADJUSTED THE POPS UP FOR THE
COASTAL REGIONS INTO EARLY AFTERNOON. THERE COULD BE A FEW TENTHS
OF ACCUMULATION W/THIS BAND. THE BAND LOOKS LIKE IT DISSIPATES AS
IT LIFTS NORTH IN THE EARLY AFTERNOON AS IT RUNS INTO MUCH DRIER
AIR.
PREVIOUS DISCUSSION...
HIGH PRESSURE WILL MOVE NORTHEAST TODAY. AS IT DOES SO, CLOUDS
WILL INCREASE IN ADVANCE OF LOW PRESSURE APPROACHING FROM THE
WEST. AS THE LOW TRACKS NORTHEAST LATER TODAY, EXPECT OVERUNNING
PRECIPITATION TO DEVELOP FROM WEST TO EAST THIS AFTERNOON IN
ADVANCE OF AN APPROACHING WARM FRONT. ANY PRECIPITATION THIS
AFTERNOON SHOULD MAINLY BE IN THE FORM OF SNOW. WESTERN AREAS
COULD SEE AROUND AN INCH OF SNOW BY LATE THIS AFTERNOON, OTHERWISE
LITTLE IN THE WAY OF ACCUMULATION IS EXPECTED ACROSS THE AREA.
HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE THE UPPER 20S
NORTH AND AROUND 30 CENTRAL AND DOWNEAST.
LOW PRESSURE WILL CONTINUE TO TRACK NORTHEAST TONIGHT
WITH PRECIPITATION CONTINUING TO EXPAND ACROSS THE REGION IN
ADVANCE OF THE APPROACHING WARM FRONT. EXPECT SNOW TO MIX WITH
AND CHANGE TO SLEET AND FREEZING RAIN FROM SOUTH TO NORTH
OVERNIGHT. A WINTER STORM WARNING HAS BEEN ISSUED FOR NORTHERN
AROOSTOOK COUNTY FOR A COMBINATION OF 4 TO 8 INCHES OF SNOW AND
SLEET AND THE POTENTIAL FOR A QUARTER TO HALF INCH OF ICE. WINTER
WEATHER ADVISORIES HAVE BEEN ISSUED FOR THE REMAINDER OF THE
FORECAST AREA FOR THE COMBINATION OF SNOW CHANGING TO A WINTRY
MIX OVERNIGHT. LOWS TONIGHT WILL RANGE FROM THE MID TO UPPER TEENS
NORTH AND MID TO UPPER 20S CENTRAL AND DOWNEAST.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
LOW PRES ACROSS SOUTHEAST ONTARIO AT 12Z FRI WILL TRACK ACROSS
MAINE FRI PM AND IS EXPECTED TO PASS EAST OF THE AREA INTO THE
MARITIMES FRI EVENING. THERE ARE STILL MODEL DIFFERENCES AS TO THE
TRACK OF THE LOW AND WHETHER IT WILL HAVE A DUAL STRUCTURE WITH
ONE LOW PASSING ACROSS THE STATE WITH A SECONDARY LOW PASSING
ACROSS THE GULF OF MAINE. PLAN TO CONTINUE TO SIDE WITH THE COLDER
SOLUTIONS SUCH AS THE NAM AND ECMWF WHICH WOULD GIVE SEVERAL
INCHES OF SNOW ACROSS THE SAINT JOHN VALLEY AND MUCH OF THE NORTH
WOODS WITH AMOUNTS TO DROP OFF TO ONLY AN INCH OR TWO ACROSS
CENTRAL PORTIONS OF THE CWA FROM DOVER-FOXCROFT TO LINCOLN AND
TOPSFIELD, AND AN INCH OR LESS IN THE GREATER BANGOR REGION. MODEL
SOUNDINGS, ESPECIALLY FROM THE NAM INDICATE A PROLONGED PERIOD OF
SLEET AND FREEZING RAIN FROM GREENVILLE- MILLINOCKET- ORIENT NORTH
WITH THE POTENTIAL FOR SIGNIFICANT SLEET ACCUMULATION AND A
QUARTER TO HALF INCH OF FREEZING RAIN. BASED ON THIS PLAN TO
UPGRADE THE WATCHES TO WARNINGS FOR NORTHERN AROOSTOOK COUNTY AND
WILL ISSUE WINTER WEATHER ADVISORIES FOR ALL ZONES TO THE SOUTH.
ALONG THE COAST, ANY FROZEN PRECIPITATION WILL BE SHORT LIVED AND
WILL CHANGE TO ALL RAIN BEFORE DAYBREAK FRI. ONCE THIS SYSTEM
MOVES EAST DRIER AIR WILL FILTER INTO THE AREA FRI NIGHT AS HIGH
PRESSURE BEGINS TO BUILDS TOWARD THE REGION FROM QUEBEC. THE HIGH
WILL CREST OVER MAINE SATURDAY MAKING FOR A SUNNY DAY WITH A
MORNING BREEZE GIVING WAY TO LIGHT WIND IN THE AFTERNOON. TEMPS
WILL CLIMB INTO THE MID 40S DOWNEAST AND INTO THE MID 30S IN THE
SAINT JOHN VALLEY SAT PM.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
SAT NIGHT AND EASTER SUNDAY ARE SHAPING UP TO BE NICE AS HIGH
PRES SLOWLY RETREATS TO THE EAST OF THE AREA. IT WILL BE DRY AND
CLEAR TO PARTLY CLOUDY WITH SOME INCREASE IN CLOUDS IN THE
AFTERNOON. TEMPERATURES WILL BE SEASONABLE WITH HIGHS NEAR 40
DEGREES IN THE CARIBOU/PRESQUE ISLE AREAS AND FROM 45 TO 50
DEGREES DOWNEAST. MODEL UNCERTAINTY IS AGAIN INTRODUCED EARLY
NEXT WEEK. THE OPERATIONAL GFS TAKES DUAL AREAS OF LOW PRES NORTH
AND SOUTH OF THE REGION MONDAY SPLITTING THE AREA AND SPARING ANY
HEAVY PRECIPITATION. THE ECMWF TAKES A DEEPER SFC LOW ACROSS THE
GULF OF MAINE LATE MON NIGHT AND TUE MORNING WITH HEAVY
PRECIPITATION MOVING ACROSS THE AREA, ESPECIALLY CENTRAL AND
DOWNEAST AREAS WITH ENOUGH COLD AIR FOR FROZEN PRECIPITATION
ACROSS NORTHERN TIER OF THE CWA. THERE IS STILL A LOT OF SPREAD IN
BOTH THE 00Z GFS AND 12Z/23RD ECMWF ENSEMBLES AND FORECAST
CONFIDENCE REMAINS LOW. ONCE THIS SYSTEM MOVES THROUGH HIGH
PRESSURE BUILDS INTO THE REGION FROM THE MIDDLE OF NEXT WEEK WITH
DRY AND SEASONABLE WEATHER.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR CONDITIONS THIS MORNING WILL GRADUALLY GIVE WAY TO
MVFR/IFR CONDITIONS IN DEVELOPING SNOW. EXPECT IFR/LIFR CONDITIONS
IN WINTRY PRECIPITATION TONIGHT.
SHORT TERM: IFR AND AT TIMES VLIFR FRI WILL GRADUALLY IMPROVE TO
MVFR BY LATE IN THE DAY FRI OR FRI EVENING WITH CONDITIONS TO
IMPROVE TO VFR OVERNIGHT FRI NIGHT AND CONTINUE SAT THROUGH SUN.
CONDITIONS WILL LOWER TO MVFR SUN NIGHT WITH IFR POSSIBLE BY LATE
MON OR MON NIGHT.
&&
.MARINE...
NEAR TERM: WIND/SEAS WILL GRADUALLY INCREASE TO SMALL CRAFT
ADVISORY LEVELS TODAY AND CONTINUE TONIGHT. VISIBILITY WILL
DECREASE TO 1 TO 3 NM IN PRECIPITATION AND PATCHY FOG.
SHORT TERM: A SMALL CRAFT ADVISORY IS IN EFFECT FOR FRIDAY AND THERE
IS STILL SOME POTENTIAL THAT A FEW WIND GUSTS COULD APPROACH LOW END
GALES. THE WIND WILL DIMINISH AND THE SEAS SUBSIDE TO BELOW
SMALL CRAFT ADVISORY LEVELS BY SAT MORNING ON THE INTRA-COASTAL
WATERS,BUT PROBABLY NOT UNTIL SAT EVENING ON THE COASTAL WATERS.
ONCE THE WIND DIMINISHES AND THE SEAS SUBSIDE CONDITIONS WILL
REMAIN BELOW SCA LEVELS THE REMAINDER OF THE WEEKEND.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING FROM 6 PM THIS EVENING TO 4 PM EDT FRIDAY
FOR MEZ001-002.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON EDT
FRIDAY FOR MEZ003>006-010-011-031-032.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 8 AM EDT
FRIDAY FOR MEZ015>017.
WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 5 AM EDT
FRIDAY FOR MEZ029-030.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT FRIDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1122 AM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TODAY AND CROSS THE REGION
TONIGHT. DRY HIGH PRESSURE WILL SET UP OVER THE AREA FRIDAY INTO
SATURDAY...BUT WITH GULF AND ATLANTIC MOISTURE RETURNING ON SUNDAY
AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. A COLD FRONT WILL CROSS
THE REGION FROM THE WEST ON MONDAY WITH DRIER CONDITIONS RETURNING
UNTIL MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM EDT THURSDAY...CONTINUING TO MONITOR PROGRESSION OF
UPPER SHORTWAVE ATOP THE ARKLATEX...AS IT RELATES TO DEVELOPING
CONVECTION ACROSS EAST MS AND WESTERN AL. THE COLD FRONT
ASSOCIATED WITH THIS SYSTEM REMAINS JUST WEST OF THE MS RIVER
AT THIS TIME...HOWEVER SHOULD QUICKLY ADVECT EAST THROUGH THE
REMAINDER OF THE MORNING. CLOSER TO HOME...NEAR TERM HIGH RES
GUIDANCE CONTINUES TO FAVOR CONVECTION SLIDING INTO EXTREME
NORTHEAST GA AND EXTREME WESTERN NC/SC AROUND 6-7PM ASSOCIATED
WITH THE SFC TROF AHEAD OF THE FRONTAL AXIS...THEN ANOTHER ROUND
OF CONVECTION JUST AHEAD OF SAID FRONT OVERNIGHT. DONT REALLY
HAVE MUCH CONFIDENCE IN THE STRENGTH/DEPTH OF THE FIRST WAVE AS
BOTH PLAN VIEW AND SOUNDING GUIDANCE FAVOR SURGING DEWPOINTS AHEAD
OF THE FRONT LATER INTO THE OVERNIGHT...WHICH ACTUALLY YIELDS THE
BEST INSTABILITY...DESPITE TIMING OF DAY. AS THE HRRR MOVES THE
INITIAL WAVE OF CONVECTION INTO THE UPPER SAVANNAH RIVER VALLEY
JUST BEFORE SUNSET...12Z NAM SOUNDINGS AT KAND EXHIBIT MODEST
CAPPING WITH POOR MID LEVEL LAPSE RATES. ONCE THE DEWPOINTS
SURGE INTO THE OVERNIGHT...SOUNDINGS THEN FAVOR SLIGHTLY IMPROVED
LAPSE RATES AND THUS INCREASING INSTABILITY. THUS...STILL THINK A
MODEST CU FIELD WILL EXPAND OVER THE AREA THROUGH MORNING/AFTERNOON
WITH CHANCES FOR ISOLATED SHRA POSSIBLE INTO THE EARLY EVENING.
BEYOND THAT...POPS STILL RAMP UP OVER THE WEST AS THE ATMOSPHERE
MOISTENS AND THE FRONT ENCROACHES PROVIDING ADDED LLV CONVERGENCE.
AS FOR CHANGES TO THE FCST...DID TWEAK TEMPERATURES/DEWPOINTS BY
BLENDING IN LATEST CONSHORT YIELDING SAID SURGING DEWPOINTS OVER
THE SAVANNAH RIVER VALLEY THIS EVENING...AND OVER THE REMAINDER OF
THE AREA OVERNIGHT. ALSO INCREASED QPF A TAD ALONG THE ESCARPMENT
PER LATEST WPCQPF...HOWEVER ANY UPSLOPING LOOKS SHORT LIVED AS
THE H85 FLOW VEERS SW RATHER QUICKLY.
PREVIOUS DISCUSSION...A MATURE AND DEEP LOW PRESSURE SYSTEM WILL
TRACK FROM THE MIDWEST TO THE GREAT LAKES THRU TONIGHT. A TRAILING
COLD FRONT WILL CROSS THE TN VALLEY TODAY...AND SHOULD PUSH INTO
THE AREA OVERNIGHT TONIGHT. GUIDANCE IS IN DECENT AGREEMENT THAT
A PRE-FRONTAL BAND OF CONVECTION WILL ENTER THE WESTERN EDGE OF
THE CWFA EARLY THIS EVENING...AND CROSS THE AREA OVERNIGHT. THE
OP MODELS SHOW GENERALLY 100-200 J/KG OF MUCAPE WITH THE LINE
(ALONG AND SOUTH OF THE NC BORDER). EVEN WITH THIS INSTBY...THE
HIGH RES MODELS INDICATE THE THE CONVECTION MAY OUTPACE THE TONGUE
OF UNSTABLE AIR TO OUR WEST...AND HENCE WEAKEN THE ACTIVITY AS IT
CROSSES THE CWFA. GIVEN THE EXPECTED TIMING OF THE PRECIP...AND
THE LACK OF INSTBY CURRENTLY OVER THE CENTRAL GULF STATES...THAT
MAKES SENSE. STILL...THERE WILL BE SOLID ENTRANCE REGION UPPER
JET DIVERGENCE AND LLVL ISENT LIFT WITHIN THE BAND...AND SO LIKELY
TO CATEGORICAL POP STILL LOOKS GOOD TONIGHT. I WILL KEEP THUNDER
MENTION TO MAINLY SLGT CHC TO CHC. TEMPS WILL BE ABOVE NORMAL
AGAIN TODAY...BUT WITH MORE CLOUD COVER AROUND. HIGHS IN THE 60S
MTNS...AND MID-UPR 70S PIEDMONT.
AS FOR SEVERE THREAT...THE NEW DAY 1 SPC CONVECTIVE OUTLOOK STILL
HIGHLIGHTS A SLIGHT RISK OVER THE TN VALLEY AND CENTRAL GULF
STATES...BUT EXPANDED THE MARGINAL RISK TO ABOUT THE WESTERN
THIRD OF THE CWFA. THE MODE OF CONVECTION LOOKS MUDDLED IN THE
CAMS...WITH MAINLY A BAND OF SHOWERS WITH EMBEDDED TSTMS (AS OPPOSED
TO A SOLID QLCS). PERHAPS THEY ARE KEYING IN ON LACK OF INSTBY AND
THE FRONT LOSING STEAM TO KEEP THE FORCING MORE LINEAR. WE WILL
MENTION THUNDER IN THE HWO...WITH THE POTENTIAL FOR A FEW ISOLATED
SEVERE WIND GUSTS...ESP IN THE WEST. IT MAY BE THE CASE THAT THE
HIGH TERRAIN MAY SEE SOME WIND ADV CRITERIA GUSTS WITHIN THE SWLY
LLJ...AS THE SHOWER MOVE IN. GIVEN THE SHORT DURATION...WITH HOLD
OFF ON ANY WIND ADVISORY. TEMPS WILL REMAIN ELEVATED AS THE FRONT
SLOWS ITS PROGRESS OVERNIGHT. LOWS RANGING FROM MID 40S ALONG THE
TN BORDER TO LWR 60S SOUTHEAST OF I-85.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
AS OF 245 AM EDT THURSDAY...THE PASSING COLD FRONT WILL BE SLOWLY
MOVING EAST OF THE AREA ON FRIDAY. THERE IS SOME UNCERTAINTY OVER
HOW QUICKLY THE BACK EDGE OF THE DEEPER MOISTURE WILL CLEAR THE
REGION WITH THE FRONTAL ZONE...BUT THE LATEST NAM APPEARS TO BE A
SLOW OUTLIER IN KEEPING PRECIPITATION CHANCES ACROSS THE REGION
THROUGH MOST OF FRIDAY. THE CURRENT THINKING IS THAT ANY LINGERING
POPS SHOULD CONSIST MAINLY OF MORNING SHOWERS EAST OF INTERSTATE 77
AND ALSO IN MOIST UPSLOPE FLOW OVER THE WESTERN MOUNTAINS.
NEVERTHELESS...THE DEPARTING SURFACE BOUNDARY COULD GET HUNG UP AS
IT APPROACHES THE SOUTHEAST COASTLINE GIVEN THE DEEP LAYER WSW FLOW
ALOFT. POST FROPA TEMPERATURES FRIDAY AFTERNOON SHOULD RUN 5 TO 10
DEGREES ABOVE CLIMO WITH THE LACK OF COLD ADVECTION AND IMPROVING
INSOLATION.
THE PENETRATION OF DRY AIR BEHIND THE FRONT...WITH SURFACE HIGH
PRESSURE BUILDING OVER TO THE NORTH...SHOULD KEEP SATURDAY DRY
DESPITE MODEL HINTS AT WEAK UPGLIDE STRAINING TO RETURN FROM THE
SOUTHEAST. THE FORECAST WILL HEDGE TOWARD A FEW MORE CLOUDS...BUT NO
PRECIPITATION AT THIS POINT. TEMPERATURES WILL BE A CATEGORY OR SO
ABOVE CLIMO...IF WE DO NOT CLOUD BACK UP TOO QUICKLY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 300 AM EDT THURSDAY...THE NUMERICAL MODELS ARE IN BETTER
AGREEMENT WITH THE HANDLING OF THE UPPER TROUGH OVER THE SOUTHERN
PLAINS ON SUNDAY...CROSSING THE SOUTHERN APPALACHIANS ON MONDAY. A
BETTER GULF MOISTURE TAP WILL GET ESTABLISHED SUNDAY AHEAD OF THE
APPROACHING SYSTEM...WITH IMPROVING CHANCES OF UPGLIDE
PRECIPITATION. THE NOSE OF OFFSHORE HIGH PRESSURE COULD LINGER EAST
OF THE APPALACHIANS JUST LONG ENOUGH ON SUNDAY FOR WEAK IN SITU COLD
AIR DAMMING TO GET ESTABLISHED. THE CURRENTLY FEATURED TEMPERATURES
IN THE 60S ACROSS THE NORTHERN TIER WILL NEED QUITE A BIT OF
ADJUSTMENT IF THAT HAPPENS.
LOW PRESSURE ZIPPING NORTHWARD FROM THE GULF OF MEXICO ALONG THE
APPROACHING FRONT WILL HELP TO FOCUS MOISTURE OVER THE AREA SUNDAY
NIGHT...AND FORCING WILL IMPROVE WITH A WEAKLY COUPLED UPPER JET
STRUCTURE OVERHEAD IN ADVANCE OF THE APPROACHING TROUGH. INSTABILITY
WILL ALSO LIKELY WRAP UP ACROSS THE SOUTHEAST PIEDMONT LATER SUNDAY
NIGHT INTO MONDAY MORNING...WITH THUNDERSTORM CHANCES THE HIGHEST
SOUTHEAST OF INTERSTATE 85 JUST AHEAD OF THE PASSING COLD FRONT.
A LOCAL QPF MAXIMUM OF AN INCH OR MORE IS POSSIBLE IN THE BEST
REGION OF SOUTHERN MOUNTAIN UPSLOPE FORCING SUN NIGHT/MON...BUT THIS
SHOULD POSE NO HYDRO ISSUES GIVEN THE DRY ANTECEDENT CONDITIONS.
CLEARING IS EXPECTED THROUGH LATE MONDAY FOLLOWING THE COLD FROPA.
UPPER RIDGING WILL BUILD BACK OVER THE REGION TUE THROUGH WED.
RETURN FLOW AROUND THE OFFSHORE SURFACE HIGH COULD ALLOW ATLANTIC
MOISTURE AND ASSOCIATED CLOUDS TO START BUILDING IN UNDER THE RIDGE
ON WED. ANTICIPATE NEAR CLIMO TEMPERATURES TUE AND WED.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
AT KCLT...DEEPER MOISTURE WILL BEGIN TO WORK IN FROM THE WEST
GRADUALLY THRU THE DAY...WITH SOME LOW VFR CIGS EXPECTED TOWARD
SUNSET. OTHERWISE...SCT-BKN CIRRUS AND A FEW CONVECTIVE CUMULUS THRU
THE DAY WITH S WINDS BECOMING SW AND GUSTY BY MIDDAY. GUIDANCE STILL
IN AGREEMENT THAT A BAND OF CONVECTION AHEAD OF A COLD FRONT WILL
CROSS THE MTNS THIS EVENING AND WEAKEN AS IT APPROACHES KCLT. STILL
THINK THERE WILL BE PREVAILING SHRA AND A CHC FOR TSRA TO WARRANT A
PROB30. BEST GUESS ON TIMING IS BETWEEN 4-7Z. THE COLD FRONT WILL
SLOW AS IT CROSSES THE MTNS...AND WITH THE -RA MOVING THRU...SHOULD
SEE AT LEAST MVFR CIGS AND/OR VSBY LATE TONIGHT.
ELSEWHERE...SIMILAR TO KCLT ABOVE. THE LOW VFR CIGS HAVE
DISSIPATED...AS FLOW REMAINS SSW...SLOWING THE GULF MOISTURE FROM
ADVANCING EASTWARD. STILL EXPECT GRADUAL INCREASE IN CU THRU THE DAY
FROM WEST TO EAST...AS A COLD FRONT APPROACHES FROM THE WEST. A
FRONTAL BAND OF SHRA/TSRA IS EXPECTED TO CROSS THE TN VALLEY
TODAY...AND REACH KAVL AROUND 1Z (ALTHO SOME SWLY UPSLOPE LIGHT SHRA
MAY DEVELOP EARLIER). THE PIEDMONT TIMING IS LESS CERTAIN...BUT
EXPECT TO BE MOVING IN AROUND 2-4Z. WINDS WILL FAVOR A S TO SW
DIRECTION THRU THE PERIOD...WITH GUSTS DURING MOST OF THE DAYLIGHT
HOURS...AND PERHAPS AGAIN LATE THIS EVENING AS FRONT APPROACHES. THE
FRONT WILL BE SLOW TO CROSS THE MTNS...AND SO LINGERING LOW CIGS
AND/OR VSBY IS EXPECTED EVEN BEHIND THE SHRA LATE TONIGHT.
OUTLOOK...DRY HIGH PRESSURE WILL TRY TO PUSH IN FROM THE NORTH ON
FRIDAY...BUT THE FRONT WILL STALL NOT FAR SOUTH OF THE
REGION...WHICH MAY KEEP A CHC FOR CLOUDS/PRECIP TO HANG AROUND THIS
WEEKEND.
CONFIDENCE TABLE...
15-21Z 21-03Z 03-09Z 09-12Z
KCLT HIGH 100% HIGH 100% MED 77% MED 77%
KGSP HIGH 100% HIGH 100% MED 69% MED 75%
KAVL HIGH 100% HIGH 94% LOW 51% MED 67%
KHKY HIGH 100% HIGH 100% MED 62% HIGH 83%
KGMU HIGH 100% HIGH 100% MED 73% MED 70%
KAND HIGH 100% HIGH 100% LOW 52% MED 71%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:
WWW.WEATHER.GOV/GSP/AVIATION
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/CDG
SHORT TERM...HG
LONG TERM...HG
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
138 PM EDT THU MAR 24 2016
.Aviation...
[Through 18Z Friday] A line of thunderstorms was taking shape to
the west of the area at 1730Z, and stretched from near MOB to the
southwest. At its current pace, it would arrive near DHN and ECP
terminals around 22-23Z, and at ABY and TLH terminals around
00-01Z. These storms could bring LIFR-IFR visibilities and gusty
winds to 30 knots or more. Otherwise, tonight we expect a mixture
of cloud layers with occasional periods of MVFR or IFR CIGS, and a
gradual improvement after sunrise on Friday. Additional showers
are possible overnight and may linger near TLH and VLD into
tomorrow. An additional round of thunderstorms will be possible
tomorrow at TLH and VLD, but confidence was not high enough to
mention TSRA in the TAFs yet.
&&
.Prev Discussion [1029 AM EDT]...
.Near Term [Rest of Today]...
Although the air mass over our forecast area at 13-14Z was fairly
dry with dewpoints in the 50s (other than along the coast), models
continue to indicate the northward advection of higher dewpoints
through the day today. Coupled with the arrival of some steeper
mid-level lapse rates from the west, and at least some mixed
sunshine today, the ingredients are in place for steady
destabilization - particularly across western parts of the area.
Convection-allowing models have been keen on developing some
showers and storms in the western parts of our area late this
afternoon as the atmosphere destabilizes and warm-air advection
gradually ramps up.
There is currently (14Z) a band of convection stretching from near
Tuscaloosa to near New Orleans, and stretching further SW
offshore. This was making steady progress east, and was generally
not depicted well in many models - even those that initialized
less than 12 hours ago. Recent runs of the HRRR have depicted this
band of convection ahead of the (now-decaying) primary MCS along
the Gulf coast, and those HRRR runs push clusters or lines of
thunderstorms into the western parts of our forecast area around
21Z to 22Z. Whether or not this specific scenario pans out remains
to be seen, but most models do show an increase in convection in
either the late afternoon or early evening. We continue to show
limited PoPs prior to 21Z, with a rapid increase in the western
half of our area between 21-00Z. Some severe wording was added in
those areas as well; given the combination of moderate instability
and shear, some of the storms could be severe from late this
afternoon into this evening.
.Short Term [Friday night Through Saturday]...
A stalled frontal boundary will be in place across Northeast
Florida out into the Gulf of Mexico. A disturbance moving through
the southern stream flow will lead to showers and thunderstorms
developing along the front and lifting northward through the day.
Model guidance continues to remain split regarding the intensity
of this system on Saturday. There seems to be reasonably good
consensus that there will be rain in the area - it`s more a
question of how much. The GFS continues to be on the stronger side
with rainfall amounts, with the NAM/Euro lighter. Overall, went
with a north-south PoP gradient with the highest values along and
south of I-10. Extensive cloudiness will keep temperatures during
the afternoon in the mid 70s.
.Long Term [Saturday Night Through Thursday]...
With one wave moving east of the region on Saturday evening, the
frontal zone will remain nearly stationary across the southern
portion of the region. Model guidance shows a second southern
stream advancing across the Central Gulf Sunday morning ahead of a
northern stream trough racing across the Central Plains. This
system should have a good deal more forcing to work with - thus
feel this system Sunday into Monday will present the greatest
heavy rainfall threat. The 24/00z Euro seems to have shifted
toward the GFS with a little greater QPF this cycle. As a result,
have increased PoPs for Sunday into the 70-80 percent range with
noticeably higher QPF.
By Sunday night, the trailing northern stream trough will be
moving across the Tennessee River Valley and should be
sufficiently strong to sweep the frontal zone south of the
forecast area by Monday afternoon. Drier air will begin to arrive
on Tuesday, with a stretch of dry conditions lasting through
Wednesday.
Thursday looks to feature a return to active weather as the next
system nears the region. Still a lot of details to be worked out
at long ranges, but it appears as though Thursday looks wet, with
some potential for another round of heavy rainfall.
Throughout the period, temperatures are expected to be above
climatology, especially with respect to overnight lows early in
the period. Some cooler and drier air will arrive Tue-Wed, but
should only return temperatures to climatology - before warming
again ahead of Thursday`s storm system.
.Marine...
In general, winds at all of our marine observation sites have been
running near or over the available model guidance. Buoy 42039 to
the south of Panama City has been around 20 knots for a few hours
and recently spiked to 23 knot sustained winds. For that reason,
we have issued a Small Craft Advisory to the west of Apalachicola
until 21Z. That may need to be extended, as some models show
another increase in winds closer to 00Z. Some models do also
indicate a lull in winds today, but given the persistence of
strong winds in the western portions of our coastal waters early
this morning, we issued the advisory.
.Fire Weather...
Hazardous fire weather conditions are not expected through at
least early next week.
.Hydrology...
Three separate periods of rainfall over the next few days will
lead to the potential for river flooding by the end of the weekend
and into next week. While there`s still some uncertainty with
respect to the amounts, it looks at this point like the primary
threat will be more river flooding and less urban flooding. The
most at risk areas for flooding would be our western areas, where
recent rains have stream flows at or just above normal.
Total rainfall from the three systems Thursday evening through
Sunday night could be in the 3 to 5 inch range with isolated
heavier totals possible.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 66 77 64 75 65 / 70 70 50 80 40
Panama City 65 72 62 72 66 / 70 60 50 80 50
Dothan 61 74 55 77 62 / 80 50 20 50 60
Albany 64 73 58 75 62 / 80 70 30 60 50
Valdosta 66 77 64 75 64 / 60 70 50 80 40
Cross City 66 79 67 77 65 / 40 60 60 60 30
Apalachicola 67 74 65 72 67 / 60 60 60 70 40
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk until midnight EDT /11 PM CDT/ tonight FOR
Coastal Bay-South Walton.
GA...NONE.
AL...NONE.
GM...Small Craft Advisory until 5 PM EDT this afternoon FOR Coastal
waters from Apalachicola to Destin FL out 20 NM-Waters from
Apalachicola to Destin FL from 20 to 60 NM.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...GODSEY
LONG TERM...GODSEY
AVIATION...LAMERS
MARINE...LAMERS
FIRE WEATHER...MOORE
HYDROLOGY...GODSEY
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
608 PM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE AREA FRIDAY THEN RETURN NORTH
AS A WARM FRONT SUNDAY. ANOTHER COLD FRONT WILL CROSS THE AREA
MONDAY. HIGH PRESSURE WILL OVERSPREAD THE REGION TUESDAY AND
WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
MAIN FORECAST PROBLEM THIS EVENING IS THE APPROACHING LINE OF
CONVECTION FROM THE WEST. IT HAS SHOT WELL AHEAD OF THE COLD
FRONT...AND WILL BE MOVING INTO A MORE STABLE ENVIRONMENT
OVERNIGHT...SO THE THREAT OF SEVERE WEATHER IN THE CWA IS
PRACTICALLY NIL. HRRR MODEL CAUGHT ON TO THIS CONCEPT BY EARLY
AFTERNOON...AND IS THE MODEL OF CHOICE FOR THE NEXT SEVERAL
HOURS.
DESPITE THE LACK OF SURFACE INSTABILITY...WE WILL BE CLOSE ENOUGH
TO THE DIVERGENT PORTION OF THE UPPER LEVEL JET TO HAVE SOME
DECENT SYNOPTIC SCALE LIFT. ADDITIONALLY...A NOTICEABLE MESOSCALE
VORTEX HAS DEVELOPED ON THE NORTHERN END OF THE STRONG CONVECTION
IN SOUTHWEST GEORGIA THIS EVENING...AND ITS REMNANTS MAY APPROACH
THE SOUTHWESTERN PORTION OF THE CWA LATE TONIGHT...PROVIDING SOME
MESOSCALE LIFT. DUE TO THESE TWO FACTORS...I HAVE ADDED ISOLATED
THUNDER OVERNIGHT.
TEMPS WILL BE QUITE MILD FOR MARCH WITH OVERNIGHT LOWS BOTTOMING
OUT IN THE LOWER TO MID 60S. NOT QUITE WARM ENOUGH TO BE A RECORD
HIGH MIN...THOUGH...WHICH IS 67 AT CAE.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL CROSS THE MIDLANDS AND CSRA DURING THE DAY
FRIDAY AND STALL JUST SOUTH AND EAST OF THE AREA FRIDAY NIGHT INTO
SATURDAY. THERE IS SOME UNCERTAINTY AS TO HOW FAR SOUTH THE FRONT
WILL MOVE BEFORE STALLING. THE NAM MODEL STALLS THE FRONT ACROSS
THE CENTRAL MIDLANDS...WHILE THE GFS AND ECMWF ALLOWS THE FRONT TO
SHIFT JUST SOUTH OF THE CSRA. THE HIGHEST INSTABILITY WILL BE
ACROSS THE EASTERN HALF OF THE FORECAST AREA FRIDAY AND
SATURDAY...SO CAN NOT RULE OUT A FEW THUNDERSTORMS DURING THE DAY.
SHOULD SEE SOME DRYING ACROSS THE NORTH AND WESTERN MIDLANDS
BEHIND THE FRONT. WILL INDICATE SLIGHT CHANCE POPS ACROSS THE
NORTH MIDLANDS SATURDAY WITH CHANCE POPS FARTHER SOUTH. SPC DOES
HAVE THE CENTRAL AND EASTERN PORTIONS OF THE CWA IN A MARGINAL
RISK OF STORMS ON FRIDAY. SHOULD SEE TEMPERATURES A FEW DEGREES
ABOVE NORMAL ON FRIDAY AND NEAR NORMAL ON SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
MEDIUM RANGE MODELS SHOW AN UPPER LEVEL TROUGH OVER THE PLAINS ON
SUNDAY MOVING EAST TO CROSS THE EASTERN STATES ON MONDAY. A WARM
FRONT IS FORECAST TO LIFT NORTHWARD ACROSS THE REGION SUNDAY
FOLLOWED BY A COLD FRONT CROSSING THE REGION MONDAY INTO MONDAY
NIGHT. SHOULD SEE A PERIOD OF PRECIP SUNDAY THEN AGAIN WITH THE
COLD FRONT MONDAY.
UPPER LEVEL RIDGE IS FORECAST TO BUILD FROM THE CENTRAL CONUS TO THE
EAST COAST TUESDAY THROUGH WEDNESDAY...MOVING OFF THE OFF THE COAST
THURSDAY. THE ECMWF IS A LITTLE SLOWER AND AMPLIFIED THAN THE GFS
AND GFS ENSEMBLE. SURFACE HIGH PRESSURE WILL BUILD ACROSS THE REGION
TUESDAY AND WEDNESDAY. THE FASTER GFS HAS PRE-FRONTAL CONVECTION
AFFECTING THE AREA THURSDAY WHILE THE SLOWER ECMWF HOLD CONVECTION
TO OUR WEST THROUGH THURSDAY.
TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS EXPECTED THROUGH AT LEAST EARLY TONIGHT. SURFACE HIGH
PRESSURE OFF THE SE COAST WILL SLIP TO THE EAST...AS A COLD FRONT
APPROACHES FROM THE WEST. A CONTINUED S TO SW LOW LEVEL FLOW WILL
CONTINUE. SHOWER ACTIVITY ASSOCIATED WITH THE FRONT IS EXPECTED TO
WEAKEN AND DIMINISH IN COVERAGE AS IT CROSS THE FORECAST AREA (FA)
LATE TONIGHT. WILL HANDLE WITH PREDOMINATE MENTION OF SHOWER WITH
MVFR CIGS/VSBYS. FRONT TO SLOWLY SLIP SOUTH THROUGH THE FA
FRIDAY...WILL INDICATE SOME DIURNAL IMPROVEMENT IN CIGS TO VFR
AND INCLUDE VCSH.
EXTENDED AVIATION OUTLOOK...SOME RAIN CHANCES WITH MAINLY LATE
NIGHT/MORNING MVFR TO POSSIBLY IFR CIGS AT TIMES FRIDAY AND
SATURDAY. BEST CHANCES OF RAIN AND RESTRICTIONS APPEAR TO BE LATE
SATURDAY NIGHT AND SUNDAY. NO IMPACTS TO AVIATION MONDAY AND
TUESDAY...EXCEPT BREEZY CONDITIONS POSSIBLE MONDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
&&
$$
SYNOPSIS...99
NEAR TERM...99
SHORT TERM...99
LONG TERM...99
AVIATION...99
SEE THE PREVIOUS LONG TERM FORECAST FORECAST DISCUSSION BELOW.
20
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
/ISSUED AT 418 AM EDT THU MAR 24 2016/
WHILE SHORT TERM FROPA SLOWS AND SETTLES NEAR THE FAR SOUTHEAST
PORTION OF THE AREA FRIDAY NIGHT INTO SATURDAY...WE STAY IN SW
FLOW ALOFT AND ONLY A BRIEF PERIOD WITH QUIET CONDITIONS AS SFC
RIDGE RESULTS IN A RATHER WEAK HYBRID CAD WEDGE. STALLED
BOUNDARY/WEDGE FRONT PROGGED TO LIFT NORTHWARD AS A WARM FRONT
LATE SATURDAY INTO SUNDAY AS GULF MOISTURE OVERRUNNING AND
ISENTROPIC FORCING BRINGS WIDESPREAD SHOWER CHANCES AND TREND OF
THUNDER CHANCES NORTHWARD. MODELS NOW IN BETTER CONSENSUS WITH
FCST EVOLUTION OF DEVELOPING LOW TO TRACK ACROSS THE TN VALLEY
SUNDAY NIGHT THEN PUSH THE ASSOCIATED COLD FRONT SOUTHEASTWARD FOR
MONDAY. AS WITH THE LAST SEVERAL SYSTEMS...WILL NEED TO WATCH FOR
UPSTREAM GULF CONVECTION POTENTIALLY ROBBING US OF MOISTURE
TRANSPORT BUT FOR NOW LOOKS LIKE A GOOD BET FOR LIKELY POPS IN THE
SUNDAY TO SUNDAY NIGHT TIME FRAME. BEST CHANCE FOR THUNDER LOOKS
TO BE SUNDAY AFTERNOON GIVEN FCST CAPE...THOUGH BETTER SHEAR
ENVIRONMENT LOOKS TO BE WITH FROPA LATE SUNDAY NIGHT INTO MONDAY.
DIFFICULT TO SAY WHICH TIME WOULD BE MORE SUPPORTIVE OF STRONGER
CONVECTION AT THE MOMENT SO WILL KEEP MONITORING OF TRENDS.
OTHERWISE THIS SECOND SYSTEM IS FOLLOWED BY A STRONGER RIDGE SO NO
WORRIES OF A LINGERING BOUNDARY TO THE SOUTH FOR TUES/WED AND
SHOULD BE DRY AND PLEASANT. ACTIVE LONGWAVE PATTERN CONTINUES
THOUGH FOR END OF FCST PERIOD WITH MOISTURE ADVECTION AHEAD OF THE NEXT
FRONTAL SYSTEM STARTING TO INFLUENCE THE AREA WED NIGHT INTO
THURS...STARTED CHANCE POPS TREND ACCORDINGLY.
DESPITE THE ACTIVE PERIOD...TEMPS FOR THE MOST PART STAY SLIGHTLY
ABOVE NORMAL THROUGHOUT. SATURDAY IS WARMEST PERIOD WITH HIGHS IN
THE MID 70S ACROSS MAJORITY OF AREA...AND MONDAY NIGHT IS COOLEST
BEHIND AFOREMENTIONED FROPA WITH LOWS IN LOW TO MID 40S BUT STILL
NOT LOW ENOUGH TO RAISE FROST/FREEZE CONCERNS.
BAKER
&&
.AVIATION...
18Z UPDATE...
ACTIVE RADAR JUST TO THE WEST. THE LATE AFTERNOON AND EVENING
HOURS WILL BE DOMINATED BY THE LINES OF CONVECTION ASSOCIATED
WITH A FRONTAL PASSAGE. THE HI-RES MODELS HAVE BEEN CONSISTENT WITH
TIMING...WITH THE FIRST LINE COMING THROUGH IN THE EARLY EVENING
AND THE SECOND OVERNIGHT. HOWEVER...AM CONCERNED THAT THIS WILL
ACTUALLY OCCUR WITH THE CURRENT RADAR PRESENTATION. WINDS WILL
REMAIN ON THE WEST SIDE. ALSO...AFTER ANY PRECIP IFR CLOUDS ARE
LIKELY...BREAKING OUT BY MID MORNING TOMORROW.
//ATL CONFIDENCE...18Z UPDATE...
LOW TO MED CONFIDENCE ON CONVECTION.
MED CONFIDENCE REMAINING ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 58 74 49 76 / 90 30 10 10
ATLANTA 55 69 50 74 / 100 20 10 10
BLAIRSVILLE 50 66 42 70 / 100 20 10 10
CARTERSVILLE 51 68 42 73 / 100 20 10 5
COLUMBUS 59 73 53 77 / 100 30 30 20
GAINESVILLE 54 70 48 71 / 100 20 10 10
MACON 63 74 53 76 / 80 40 30 20
ROME 49 67 41 73 / 100 10 10 5
PEACHTREE CITY 56 70 45 75 / 100 20 20 10
VIDALIA 66 76 61 75 / 50 50 30 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...NLISTEMAA
LONG TERM....20
AVIATION...NLISTEMAA
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
126 PM EDT THU MAR 24 2016
.PREV DISCUSSION... /ISSUED 957 AM EDT THU MAR 24 2016/
UPDATE...
COLD FRONT IS CURRENTLY SITUATED JUST WEST OF THE MISSISSIPPI
RIVER THIS MORNING...WHILE THE SQUALL LINE IS JUST NOW CROSSING
THE RIVER. THE MODELS CONTINUE TO SHIFT THE FILLING LOW PRESSURE
SYSTEM/SHORTWAVE OFF TO THE NORTHEAST.
THERE IS SOME DIFFERENCES BETWEEN THE HI-RES MODELS MODELS THIS
MORNING...WITH THE HRRR A LITTLE FASTER THAN THE REST. THE ARW HAS
BEEN THE MOST CONSISTENT. SCATTERED SHOWERS WILL BE POSSIBLE FOR
THE LATE MORNING/EARLY AFTERNOON IN THE WESTERN PORTION OF THE
CWFA. THE STRONGER ACTIVITY SHOULD BEGIN TO MOVE IN AROUND 18Z.
WITH THE MAIN COLD POOL WELL TO THE NORTH...THE MID LEVEL LAPSE
RATES ARE NOT AS STEEP AS THEY WERE YESTERDAY. HOWEVER...THERE
WILL BE ENOUGH SHEAR AND WITH A 40-50KT LLJ...THE FRONT MAY
PROVIDE ENOUGH LIFT TO PROVIDE ENOUGH POTENTIAL FOR A FEW SEVERE
THUNDERSTORMS LATE THIS AFTERNOON AND EVENING. THE PRIMARY THREATS
SHOULD BE DAMAGING WIND GUSTS AND POSSIBLY SOME LARGE HAIL CLOSEST
TO THE MID LEVEL COLD POOL. AN ISOLATED TORNADO IS STILL
POSSIBLE.
FOR THE UPDATE...HAVE TWEAKED POPS A BIT FOR EARLY THIS MORNING.
THE SHOWERS HAVE BEEN A LITTLE SLOWER TO PROGRESS INTO NW GA.
TEMPS/DEWS LOOKED ALRIGHT SO MADE VERY LITTLE CHANGE.
PREV DISCUSSION... /ISSUED 726 AM EDT THU MAR 24 2016/
PREV DISCUSSION... /ISSUED /
SHORT TERM /TODAY THROUGH FRIDAY/...
LATEST SURFACE ANALYSIS SHOWS HIGH PRESSURE WELL OFF THE CAROLINA
COAST AND THE MAJOR INFLUENCER OF THE SE WEATHER PATTERN. RETURN
FLOW FROM THIS HIGH IS PRODUCING SOUTHERLY FLOW BOTH AT GROUND
LEVEL AND JUST OFF THE SURFACE ALLOWING FOR AN INITIAL 5K FT DECK
OF CLOUDS TO PUSH INTO PORTIONS OF NORTH GA. SOUTHERLY FLOW ALSO
PLAYING A MAJOR ROLE IN KEEPING TEMPERATURES ELEVATED THIS
OVERNIGHT PERIOD WITH VALUES HOLDING IN THE 50S AND EVEN SOME 60S
STILL OUT THERE.
THE MAIN ISSUE AT LEAST INITIALLY WILL BE THE TIMING OF THE PRE-
FRONTAL ACTIVITY AS WELL AS THE STRENGTH OF THAT ACTIVITY. HI RES
MODELS ARE AGREEING A LITTLE BETTER WITH THE LATEST RUNS IN
BRINGING A LINE OF SHRA TO THE AREA BY 20Z. MUCAPE DURING THIS
TIME PERIOD AND PRIOR TO 00Z LOOKS ONLY ON THE ORDER OF 50 TO 100
J/KG AND PREFER TO KEEP THUNDER OUT OF THE FORECAST FOR THIS FIRST
PHASE.
PHASE 2 HOWEVER WHICH IS FROM 00Z TO 06Z LOOKS TO INCLUDE
MORE ROBUST CONVECTION WITH CAPE VALES NEAR 1000 J/KG PUSHING IN
FROM THE SW AND ROUGHLY ALONG AND SOUTH OF THE I85 CORRIDOR. IN
FACT...ALTHOUGH GREATER SHEAR WILL BE TO THE NORTH....IT IS THIS
AFOREMENTIONED ZONE THAT COULD END UP HAVING THE STRONGER STORMS
GIVEN THE BETTER BALANCE OF INSTABILITY AND SHEAR. OVERALL...THESE
SHEAR VALUES FAVOR DAMAGING WIND GUSTS ALTHOUGH LOW LEVEL HELICITY
IS SUFFICIENT FOR ISOLATED TORNADOES AS WELL. THE LARGE HAIL WILL
BE CONFINED TO THE AREAS WITH THE GREATER MID LEVEL INSTABILITY
WHICH SHOULD BE THE SOUTHERN ZONES BASED ON LATEST MODEL DATA.
THE BIGGEST QUESTION FOR THIS FORECAST CYCLE IS ACTUALLY HOW FAR
SOUTH THE FRONT WILL PROGRESS AND THE TIMING OF ANY CLEARING. GFS
AND ECMWF CONTINUE TO BE THE MOST AGGRESSIVE WITH FRONTAL PASSAGE
BRINGING CLEARING CONDITIONS TO THE NORTH GEORGIA REGION LATE
THURSDAY NIGHT INTO FRIDAY MORNING WHILE THE NAM12 HANGS THE FRONT
UP OVER N GA KEEPING POPS IN MUCH LONGER. FOR NOW WILL GO WITH THE
CONSENSUS OF THE MORE PROGRESSIVE MODELS WITH A GOOD CLEARING
TREND DOWN TO MACON THROUGH FRIDAY MORNING.
DEESE
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
WHILE SHORT TERM FROPA SLOWS AND SETTLES NEAR THE FAR SOUTHEAST
PORTION OF THE AREA FRIDAY NIGHT INTO SATURDAY...WE STAY IN SW
FLOW ALOFT AND ONLY A BRIEF PERIOD WITH QUIET CONDITIONS AS SFC
RIDGE RESULTS IN A RATHER WEAK HYBRID CAD WEDGE. STALLED
BOUNDARY/WEDGE FRONT PROGGED TO LIFT NORTHWARD AS A WARM FRONT
LATE SATURDAY INTO SUNDAY AS GULF MOISTURE OVERRUNNING AND
ISENTROPIC FORCING BRINGS WIDESPREAD SHOWER CHANCES AND TREND OF
THUNDER CHANCES NORTHWARD. MODELS NOW IN BETTER CONSENSUS WITH
FCST EVOLUTION OF DEVELOPING LOW TO TRACK ACROSS THE TN VALLEY
SUNDAY NIGHT THEN PUSH THE ASSOCIATED COLD FRONT SOUTHEASTWARD FOR
MONDAY. AS WITH THE LAST SEVERAL SYSTEMS...WILL NEED TO WATCH FOR
UPSTREAM GULF CONVECTION POTENTIALLY ROBBING US OF MOISTURE
TRANSPORT BUT FOR NOW LOOKS LIKE A GOOD BET FOR LIKELY POPS IN THE
SUNDAY TO SUNDAY NIGHT TIME FRAME. BEST CHANCE FOR THUNDER LOOKS
TO BE SUNDAY AFTERNOON GIVEN FCST CAPE...THOUGH BETTER SHEAR
ENVIRONMENT LOOKS TO BE WITH FROPA LATE SUNDAY NIGHT INTO MONDAY.
DIFFICULT TO SAY WHICH TIME WOULD BE MORE SUPPORTIVE OF STRONGER
CONVECTION AT THE MOMENT SO WILL KEEP MONITORING OF TRENDS.
OTHERWISE THIS SECOND SYSTEM IS FOLLOWED BY A STRONGER RIDGE SO NO
WORRIES OF A LINGERING BOUNDARY TO THE SOUTH FOR TUES/WED AND
SHOULD BE DRY AND PLEASANT. ACTIVE LONGWAVE PATTERN CONTINUES
THOUGH FOR END OF FCST PERIOD WITH MOISTURE ADVECTION AHEAD OF THE NEXT
FRONTAL SYSTEM STARTING TO INFLUENCE THE AREA WED NIGHT INTO
THURS...STARTED CHANCE POPS TREND ACCORDINGLY.
DESPITE THE ACTIVE PERIOD...TEMPS FOR THE MOST PART STAY SLIGHTLY
ABOVE NORMAL THROUGHOUT. SATURDAY IS WARMEST PERIOD WITH HIGHS IN
THE MID 70S ACROSS MAJORITY OF AREA...AND MONDAY NIGHT IS COOLEST
BEHIND AFOREMENTIONED FROPA WITH LOWS IN LOW TO MID 40S BUT STILL
NOT LOW ENOUGH TO RAISE FROST/FREEZE CONCERNS.
BAKER
&&
.AVIATION...
18Z UPDATE...
ACTIVE RADAR JUST TO THE WEST. THE LATE AFTERNOON AND EVENING
HOURS WILL BE DOMINATED BY THE LINES OF CONVECTION ASSOCIATED
WITH A FRONTAL PASSAGE. THE HI-RES MODELS HAVE BEEN CONSISTENTWITH
TIMING...WITH THE FIRST LINE COMING THROUGH IN THE EARLY EVENING
AND THE SECOND OVERNIGHT. HOWEVER...AM CONCERNED THAT THIS WILL
ACTUALLY OCCUR WITH THE CURRENT RADAR PRESENTATION. WINDS WILL
REMAIN ON THE WEST SIDE. ALSO...AFTER ANY PRECIP IFR CLOUDS ARE
LIKELY...BREAKING OUT BY MID MORNING TOMORROW.
//ATL CONFIDENCE...18Z UPDATE...
LOW TO MED CONFIDENCE ON CONVECTION. MED CONFIDENCE REMAINING
ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 78 57 73 48 / 70 90 30 10
ATLANTA 76 56 68 49 / 90 100 20 10
BLAIRSVILLE 68 50 65 41 / 90 100 20 10
CARTERSVILLE 72 51 67 41 / 90 100 20 10
COLUMBUS 78 59 73 52 / 70 100 30 30
GAINESVILLE 71 54 69 48 / 80 100 20 10
MACON 80 63 73 51 / 50 80 40 30
ROME 71 49 67 41 / 90 100 10 10
PEACHTREE CITY 76 56 70 44 / 80 100 20 20
VIDALIA 80 66 76 60 / 20 50 50 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...
AVIATION...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
212 PM CDT THU MAR 24 2016
.SHORT TERM...
212 PM CDT
THROUGH FRIDAY...
THE MAIN CONCERN WILL FOCUS ON THE PERIOD OF HEAVY SNOW EXPECTED TO
IMPACT PORTIONS OF NORTHERN ILLINOIS LATE THIS AFTERNOON AND VERY
EARLY THIS EVENING.
THE SURFACE LOW IS NOW SHIFTING INTO SOUTHEASTERN LOWER MICHIGAN
EARLY THIS AFTERNOON...AND THIS IS NOW ALLOWING THE WINDS TO PICK UP
OUT OF THE NORTH...AND COLDER AIR TO SINK SOUTHWARD OVER THE AREA.
THE MID-LEVEL DRY SLOT HAS ARRIVED INTO NORTHERN ILLINOIS...AND THIS
IS RESULTING IN A TEMPORARY END TO THE PRECIPITATION FOR MANY AREAS.
HOWEVER...WE ARE NOT DONE WITH THIS STORM SYSTEM YET...AS ATTENTION
IS NOW FOCUSED ON THE BAND OF MODERATE TO HEAVY SNOW THAT HAS
DEVELOPED OUT WEST NEAR THE MISSISSIPPI RIVER.
THIS AREA OF PRECIPITATION IS ASSOCIATED WITH A BAND OF STRONG
FRONTOGENESIS SETTING UP WITHIN THE SYSTEMS MID-LEVEL DEFORMATION
ZONE. MODEL GUIDANCE CONTINUES TO SUGGEST THAT THIS BAND OF FGEN IS
COINCIDING WITH THE THE PERIOD OF BEST MID AND UPPER LEVEL Q-VECTOR
CONVERGENCE ASSOCIATED WITH THE APPROACHING NEUTRAL TO NEGATIVELY
TILTED MID LEVEL DISTURBANCE. AS A RESULT...IT IS LIKELY THAT THIS
BAND OF MODERATE TO HEAVY SNOW WILL CONTINUE TO SHIFT EASTWARD
ACROSS FAR NORTHERN ILLINOIS THROUGH THE LATE AFTERNOON HOURS.
CURRENT OBSERVATIONS UNDER THIS BAND OF SNOW ARE INDICATING 1/2 TO
1/4 SM SNOW...SO I WILL BE INCLUDING HEAVY SNOW WORDING IN THE
FORECAST...AND WILL ALSO BE ISSUING AN SPS TO HIGHLIGHT THE VERY LOW
VISIBILITIES AND POSSIBLE QUICK SLUSHY ACCUMULATION EXPECTED DURING
THE AFTERNOON COMMUTE. OVERALL...THERE APPEARS TO BE A 2 TO 4 HOUR
WINDOW FOR THIS MODERATE TO HEAVY SNOW TO IMPACT FAR NORTHERN
ILLINOIS BEFORE THE FORCING WANES. GIVEN TEMPERATURES ARE
MARGINAL...AND WILL LIKELY COOL TO NEAR FREEZING UNDER THE HEAVY
PRECIP RATES...SNOW WILL LIKELY STRUGGLE TO ACCUMULATE MUCH ON AREA
ROADS...BUT A QUICK 1-2 INCHES IS CERTAINLY POSSIBLE ON GRASSY AND
ELEVATED SURFACES BEFORE THE SNOW ENDS EARLY THIS EVENING. THE BEST
CHANCE FOR SOME ACCUMULATIONS STILL APPEARS TO BE ALONG AND NORTH OF
A LINE FROM NEAR DIXON...NORTHEASTWARD TO WAUKEGAN.
KJB
&&
.LONG TERM...
354 AM CDT
SATURDAY NIGHT THROUGH THURSDAY...
FRIDAY THROUGH WEDNESDAY...
NICE WEATHER EXPECTED FRIDAY AS UPPER TROUGH FROM OUR CURRENT
MID-WEEK STORM SYSTEM LIFTS AWAY TO THE NORTHEAST AND LOW
AMPLITUDE SHORT WAVE RIDGE DEVELOPS OVERHEAD. SURFACE HIGH
PRESSURE DRIFTS EAST ACROSS THE CWA DURING THE DAY...WITH
SUBSIDENCE AND DRY COLUMN EXPECTED TO PRODUCE A GOOD DEAL OF
SUNSHINE. LIGHT WINDS IN THE VICINITY OF THE RIDGE AXIS THROUGH
EARLY AFTERNOON SHOULD ALLOW FOR TYPICAL SPRING LAKE BREEZE
DEVELOPMENT...THOUGH 925-950 MB MODEL THERMAL FIELDS INDICATE
INLAND AREAS SHOULD BE ABLE TO REACH HIGHS IN THE 48-52 DEGREE
RANGE. WINDS TURN SOUTHEAST BY EVENING...SETTING UP A SEASONABLY
COOL NIGHT AS MID AND HIGH CLOUDS EVENTUALLY INCREASE FROM THE
WEST AHEAD OF THE NEXT UPSTREAM DISTURBANCE.
THAT DISTURBANCE IS ACTUALLY A COUPLE OF INDIVIDUAL SHORT WAVES
WHICH HELP TO AMPLIFY A BROAD UPPER TROUGH ACROSS THE CENTRAL
CONUS THROUGH THE WEEKEND...ONE MOVING ACROSS THE UPPER
MISSISSIPPI VALLEY SATURDAY WHILE THE OTHER DIGS ACROSS THE
CENTRAL/SOUTHERN PLAINS AND EVENTUALLY INDUCES A DEEPENING AREA OF
LOW PRESSURE OVER THE OHIO VALLEY AND LOWER GREAT LAKES REGION BY
LATE SUNDAY AS IT BEGINS TO SWING NORTHEAST FROM THE BASE OF THE
TROUGH. MODEST HEIGHT FALLS DEVELOP INTO THE AREA SATURDAY MORNING
WITH THE APPROACH OF THE NORTHERN WAVE...THOUGH LOW LEVEL MOISTURE
RETURN IS LIMITED TO A NARROW CORRIDOR AHEAD OF THE COLD FRONT
WHICH TRAILS THE SURFACE LOW PRESSURE REFLECTION OVER WISCONSIN.
THUS PRECIP POTENTIAL DURING THE DAY SATURDAY LOOKS TO BE FOCUSED
ACROSS THE WESTERN HALF OF THE CWA AND PRIMARILY MIDDAY INTO THE
AFTERNOON WITH THE ADVANCING COLD FRONT. DESPITE INCREASING MID-
HIGH CLOUD COVER...SOUTH WINDS SHOULD HELP WARM TEMPS INTO THE 50S
OVER MUCH OF THE AREA AND TO AROUND 60 ACROSS THE SOUTH.
WRF...WHICH IS SLOWER WITH THE FRONT...INDICATES A BIT OF A
SOUTHEAST COMPONENT ALONG THE IL LAKESHORE WHICH MAY INDICATE A
VERY WEAK LAKE BREEZE.
FRONT PUSHES EAST ACROSS THE AREA SATURDAY EVENING...THOUGH
LATEST MODEL RUNS REALLY SCALE BACK PRECIP DURING THE EVENING AS
THE STRONGER SYNOPTIC FORCING BECOMES SPLIT TO OUR NORTH AND WELL
TO THE SOUTH. AS THE SOUTHERN LOW BEGINS TO DEVELOP AND DEEPEN
LATE SATURDAY NIGHT...FRONTOGENETIC FORCING ALONG THE SOUTH END OF
THE FRONT INCREASES AND ALLOWS RAIN TO DEVELOP FROM THE SOUTHWEST
INTO PARTS OF THE CWA BY SUNDAY MORNING. MEDIUM-RANGE GUIDANCE
REMAINS A LITTLE DIFFERENT WITH THE EXACT LOW TRACK ACROSS THE
MIDWEST SUNDAY/SUNDAY NIGHT...THOUGH GENERALLY FOCUS PRECIP ACROSS
THE SOUTHEAST HALF TO TWO THIRDS OF THE FORECAST AREA. PARTIAL
THICKNESS FIELDS INDICATE NEARLY ALL OF THE PRECIP WOULD FALL AS
RAIN...THOUGH THE SLIGHTLY FARTHER NORTHWEST TRACK OF THE 12Z
ECMWF WOULD SUPPORT A BRIEF MIX OR CHANGEOVER TO WET SNOW LATE
SUNDAY NIGHT OR EARLY MONDAY BEFORE PRECIP ENDS. CURRENT MODEL
PROGS GENERATE SOME SUBSTANTIAL QPF TOTALS ACROSS THE SOUTHEAST
PORTION OF THE FORECAST AREA THROUGH SUNDAY NIGHT...FROM 0.50
INCHES IN THE FARTHER SOUTHEAST GFS TO 1.25 INCHES IN THE ECMWF.
RISING HEIGHTS THEN DEVELOP INTO THE AREA MONDAY AS THE UPPER
TROUGH PULLS AWAY TO THE EAST...WITH GOOD MODEL CONSENSUS IN
DEVELOPING BROAD UPPER RIDGE ACROSS THE AREA THROUGH MID-WEEK
BEFORE THE NEXT AMPLIFIED UPPER TROUGH APPROACHES. SURFACE HIGH
PRESSURE OVER THE AREA MONDAY INTO TUESDAY WILL LIKELY SUPPORT
LAKE BREEZES BOTH DAYS...WITH TEMPS MODERATING FROM THE MID-40S TO
MID 50S EAST TO WEST MONDAY AND TO THE 55-60 RANGE ON TUESDAY.
SURFACE LOW DEVELOPING TO THE WEST OF THE AREA BY WEDNESDAY WOULD
SUPPORT CONTINUED SOUTH FLOW AND MILD TEMPS MID-WEEK...THOUGH WITH
AN INCREASING CHANCE OF RAIN.
RATZER
&&
.AVIATION...
FOR THE 18Z TAFS...
LOW PRESSURE WILL SHIFT EASTWARD SOUTH OF THE TERMINALS EARLY THIS
AFTERNOON. THIS WILL RESULT IN NORTHERLY WINDS...SHIFTING MORE NORTH-
NORTHWESTERLY LATER THIS AFTERNOON AND EVENING. WINDS GUSTS COULD
ALSO APPROACH 25 KT LATER THIS AFTERNOON AS THE SURFACE LOW SHIFTS
EASTWARD. OTHERWISE...IT APPEARS THAT SHOWERS WILL CONTINUE FOR THE
NEXT HOUR OR TWO AT THE EASTERN TERMINALS BEFORE ENDING FOR A
PERIOD. CIGS ALSO LOOK TO IMPROVE OVER THE EASTERN TAF SITES FOR A
COUPLE HOUR PERIOD THIS AFTERNOON BEFORE THEY DETERIORATE AGAIN
LATER THIS AFTERNOON. WE ARE STILL EXPECTING A BAND OF POTENTIALLY
HEAVY SNOW TO SET UP OVER NORTHERN ILLINOIS THROUGH THE AFTERNOON.
HOWEVER...AT THIS TIME IT APPEARS THAT KRFD WOULD STAND THE BEST
CHANCES AT SEEING LOW VSBYS AND POSSIBLE ACCUMULATIONS FROM THIS
BAND OF SNOW. FARTHER EAST...IT WILL TAKE UNTIL VERY LATE THIS
AFTERNOON...LIKELY AFTER 22-23 UTC BEFORE THE COLUMN COOLS ENOUGH TO
SUPPORT SOME SNOW. THEREFORE...IT APPEARS THAT THE EASTERN TERMINALS
MAY ONLY SEE A VERY SNORT PERIOD OF SOME SNOW BEFORE THE
PRECIPITATION ENDS EARLY THIS EVENING.
KJB
&&
.MARINE...
315 AM CDT
MODERATELY STRONG NORTHEASTERLY WINDS OF 30 TO 35 KT ARE IN PLACE
OVER MUCH OF LAKE MICHIGAN EARLY THIS MORNING AHEAD OF AN AREA
OF LOW PRESSURE OVER NORTHERN MISSOURI. WEAKER FLOW IS IN PLACE
ACROSS THE FAR SOUTHERN END OF LAKE MICHIGAN WHERE A FRONTAL
TROUGH IS IN PLACE. THE LOW WILL MOVE JUST SOUTH OF LAKE MICHIGAN
THIS AFTERNOON WITH WINDS BACKING TO THE NORTH AND GALES SPREADING
SOUTH ACROSS THE REMAINDER OF THE LAKE. GALES SHOULD DIMINISH
TONIGHT AND WINDS WILL BECOME LIGHT ON FRIDAY AS A RIDGE AXIS
MOVES OVER THE LAKE. FRESH SOUTHERLY FLOW RESUMES LATE FRIDAY INTO
SATURDAY AS THE RIDGE DEPARTS TO THE EAST ANOTHER FRONT MOVES
ACROSS LAKE MICHIGAN SATURDAY NIGHT INTO SUNDAY TURNING WINDS
NORTH AGAIN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 PM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779 UNTIL 4 AM FRIDAY.
&&
$$
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
121 PM CDT THU MAR 24 2016
.UPDATE...
Issued at 1113 AM CDT Thu Mar 24 2016
Surface low making its way across Central Illinois this morning,
dragging showers and scattered thunder with it. Forecast going
well overall with the timing of the precip. Showers on the back
side of the low limited in hi res models. Gusty winds following
the low as it deepens and tightens the pressure gradient. Cooler
afternoon with gusty winds anticipated and on track. No major
updates anticipated...but some small adjustments here and there
for hourly trends.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 323 AM CDT Thu Mar 24 2016
08z/3am surface analysis shows 997mb low over northern Missouri,
with stationary frontal boundary extending into north-central
Illinois. Based on latest obs, it appears the boundary extends from
near Macomb to just north of Pontiac. To the south of the front in
the warm sector, much of the KILX CWA has current temps in the lower
60s. Meanwhile to the north of the boundary, readings are only in
the lower 40s in Galesburg. A broken line of convection associated
with the approaching low developed across eastern Kansas/western
Missouri last evening...however that activity diminished as it
tracked northeastward and skirted the NW CWA around midnight. Latest
radar imagery shows very little going on across central Illinois:
however, showers are beginning to develop upstream and should spread
into the area over the next couple of hours. HRRR has been quite
persistent showing the showers becoming more widespread along/west
of I-55 after 09z/4am. As the low and accompanying cold front get
closer, showers and a few thunderstorms will develop across the
entire area early this morning. Have therefore carried categorical
PoPs across the board. The low will track to near the Chicago area
by midday, pulling the cold front through central Illinois and
pushing the widespread rain into Indiana at that time. Have
therefore lowered PoPs to just low chance across most of the area
this afternoon. The exception will be northwest of the Illinois
River, where deformation zone rain and snow showers will persist
through the afternoon. High temperatures will be achieved early in
the day, with readings falling steadily this afternoon. By mid
afternoon, temps will range from the upper 30s northwest of the
Illinois River...to the middle 50s near the Indiana border.
.LONG TERM...(Friday through Wednesday)
ISSUED AT 323 AM CDT Thu Mar 24 2016
As low pressure continues to lift into the eastern Great Lakes, a
few rain/snow showers may linger along/north of the I-74 corridor
early this evening before coming to an end before midnight. Skies
will initially be overcast, but will clear from west to east
overnight with lows dropping into the upper 20s and lower 30s. High
pressure will build into the region on Friday, leading to mostly
sunny and cool conditions with highs in the lower to middle 50s.
Once the high shifts off to the east, the next system will begin to
approach from the west over the weekend. Models have been
struggling with this feature for the past several days, and
agreement remains poor with the 00z Mar 24 run. The main issues
have been how much and how quickly an approaching short-wave trough
will amplify. Given the progressive flow pattern, have generally
preferred the weaker and faster solution. As such, will continue to
feature highest rain chances Sunday/Sunday night...followed by a
return to dry weather for Monday and Tuesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 115 PM CDT Thu Mar 24 2016
Low pressure center working through Central Illinois this
afternoon, southwesterly winds veering to more nw/northerly by end
of day. A brief shower on the back edge of the system possible,
mainly for PIA. But for the most part, low cigs dominate through
the overnight hours. Keeping MVFR cigs in place... and winds
remaining somewhat gusty in the tightening pressure gradient.
Clearing anticipated in the morning, although models are very
widely varied in timing.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE, IL
1153 AM CDT THU MAR 24 2016
.UPDATE...
1153 AM CDT
THE MAIN CONCERN TODAY WILL BE IN REGARDS TO THE POTENTIAL FOR A
PERIOD OF HEAVY SNOW THIS AFTERNOON...PRIMARILY OVER FAR NORTHERN
ILLINOIS.
THE SURFACE LOW IS CENTERED OVER CENTRAL ILLINOIS...NEAR KBMI...WITH
THE QUASI-STATIONARY SURFACE BOUNDARY LOCATED JUST SOUTH OF LAKE
MICHIGAN. TEMPERATURES CONTINUE TO VARY WIDELY ON EITHER SIDE OF THE
FRONT...WITH 30S TO LOW 40S NORTH...AND 50S TO NEAR 60 SOUTH. PLENTY
OF RAIN IS ONGOING NORTH OF THE LOW OVER NORTHERN ILLINOIS. A LINE
OF THUNDERSTORMS IS ALSO SHIFTING EASTWARD ACROSS MY SOUTHERN
CWA...AND THIS OCCURRING JUST AHEAD OF THE MID-LEVEL DRY SLOT
PUNCHING EAST-NORTHEASTWARD INTO WESTERN ILLINOIS...PER THE LATEST
WATER VAPOR IMAGERY. WE EXPECT THIS LINE OF STORMS TO CONTINUE
EASTWARD OVER MAINLY THE SOUTHERN HALF OF THE AREA THROUGH EARLY
AFTERNOON...BEFORE THE DRY SLOT BEGINS TO SHIFT INTO CENTRAL
ILLINOIS.
OTHERWISE THE MAIN CONCERN THIS AFTERNOON IS THE CONTINUED POTENTIAL
FOR A BAND OF MODERATE TO POSSIBLY HEAVY SNOW...INITIALLY MIXING
WITH SLEET...OVER FAR NORTH CENTRAL ILLINOIS THIS AFTERNOON.
REGIONAL RADAR IMAGERY OVER THE PAST HOUR HAS REALLY SHOWN AN UPTICK
IN THE DEVELOPMENT OF PRECIPITATION OVER SOUTHEASTERN IOWA/FAR
NORTHERN MISSOURI WITHIN THE MID-LEVEL DEFORMATION ZONE. MODEL
GUIDANCE CONTINUES TO ADVERTISE A BAND OF FRONTOGENESIS SETTING UP
OVER NORTHERN ILLINOIS...WITHIN THIS DEFORMATION ZONE. GIVEN THIS
LOOKS TO COINCIDE WITH THE THE PERIOD OF BEST MID AND UPPER LEVEL Q-
VECTOR CONVERGENCE ASSOCIATED WITH THE APPROACHING NEUTRAL TO
NEGATIVELY TILTED MID LEVEL DISTURBANCE...IT APPEARS LIKELY THAT A
PERIOD OF MODERATE TO HEAVY WET SNOW WILL SET UP THROUGH THE
AFTERNOON OVER FAR NORTHERN ILLINOIS. THERE ALSO CONTINUES TO BE A
FEW LIGHTNING STRIKES OCCURRING WITHIN THIS DEVELOPING BAND OF
PRECIP. THEREFORE...WE CANNOT RULE OUT A RUMBLE OR TWO OF THUNDER
WITH SOME OF THIS HEAVIER SNOW. ACCUMULATIONS OF A FEW INCHES ARE
STILL POSSIBLE...ESPECIALLY ON GRASSY AREAS...BUT WE CURRENTLY
CONTINUE TO MENTION MORE CONSERVATIVE AMOUNTS AROUND AN
INCH...ESPECIALLY NORTH OF A LINE FROM NEAR DIXON...NORTHEASTWARD TO
WAUKEGAN. NEAR TERM TRENDS WILL CONTINUED TO BE MONITORED THIS
AFTERNOON TO SEE IF HIGHER AMOUNTS AND AN SPS ARE JUSTIFIED. ANY
SNOW SHOULD END QUICKLY THIS EVENING...WITH LITTLE IF ANY
ACCUMULATIONS EXPECTED INTO CHICAGO.
KJB
&&
.SHORT TERM...
354 AM CDT
TODAY AND TONIGHT...
STRONG SPRING STORM SYSTEM WORKING ITS WAY THROUGH THE MIDWEST
THIS MORNING. WATER VAPOR IMAGERY INDICATES THE MAIN MID-LEVEL
CIRCULATION WAS CENTERED NEAR KANSAS CITY AT 08Z...WITH A 998 MB
SURFACE LOW JUST NORTHEAST OF KMCI AND A STATIONARY FRONT
EXTENDING NORTHEASTWARD ACROSS NORTHERN IL AND INTO FAR NORTHWEST
INDIANA JUST SOUTH OF LAKE MICHIGAN. 08Z SURFACE OBS DEPICT A 26
DEGREE DIFFERENCE IN TEMPS ACROSS THE CWA...FROM 35 AT WAUKEGAN TO
61 AT RENSSELAER INDIANA. THIS WILL CONTINUE TO BE THE CASE TODAY
AS THE SURFACE LOW TRACKS ALONG THE FRONT...AND EVENTUALLY MOVES
EAST OF THE AREA LATE THIS AFTERNOON.
WFO LOT CWA IS CURRENTLY IN A LULL BETWEEN BAND OF SHOWERS AND
THUNDERSTORMS WHICH LIFTED ACROSS THE AREA OVER THE PAST SEVERAL
HOURS. AREA OF RAIN/EMBEDDED THUNDER OVER EASTERN MISSOURI AND
WEST CENTRAL IL IS EXPECTED TO SPREAD NORTHEAST BACK INTO THE AREA
THIS MORNING HOWEVER...AS DEEP FORCING INCREASES AHEAD OF
APPROACHING UPPER TROUGH AND STRONG MOISTURE TRANSPORT CONTINUES
PARTICULARLY INTO THE SOUTHEASTERN HALF OF THE FORECAST AREA. DRY
SLOT THEN PUSHES IN FROM THE SOUTHWEST MIDDAY/AFTERNOON WHICH
SHOULD CURTAIL PRECIP ACROSS THE SOUTH/SOUTHEAST...WHILE THE
TRAILING PORTION OF THE SYSTEM DEFORMATION ZONE PASSES ACROSS
NORTHERN ILLINOIS. FORECAST SOUNDINGS AND THICKNESS FIELDS
INDICATE THE COLUMN WILL COOL ENOUGH TO CHANGE LINGERING
DEFORMATION BAND PRECIP OVER TO SOME WET SNOW BEFORE ENDING EARLY
THIS EVENING...WITH A BRIEF PERIOD OF MIXED RAIN/SNOW/SLEET DURING
THE TRANSITION. GUIDANCE IS FAIRLY BULLISH WITH POTENTIAL FOR
ACCUMULATING SNOW ACROSS NORTH CENTRAL IL DURING THE LATE
AFTERNOON...AND WHILE SOME ACCUMULATION IS LIKELY...3-4 INCHES
INDICATED BY VARIOUS WRF RUNS MAY BE OVERDONE. EVEN SO...IT DOES
APPEAR THAT SOME ACCUMULATION CAN BE EXPECTED ACROSS FAR NORTH
CENTRAL AND NORTHERN IL WITH PERHAPS AN INCH ON GRASSY OR ELEVATED
SURFACES. PRECIP THEN WINDS DOWN QUICKLY THIS EVENING AS THE
SYSTEM DEPARTS TO THE EAST.
TEMPS TODAY ARE NOT EXPECTED TO STRAY TOO FAR FROM WHERE THEY ARE
NOW WITH THE FRONT BISECTING THE FORECAST AREA. SOME NORTHWARD
MOVEMENT OF THE BOUNDARY IS POSSIBLE ESPECIALLY SOUTH/SOUTHEAST OF
THE CHICAGO METRO AREA...THOUGH CONFIDENCE IS FAIRLY LOW ON EXACT
PLACEMENT. COLDER AIR SURGES IN THIS EVENING ON BLUSTERY NORTH
WINDS AS SKIES CLEAR OUT LATE.
RATZER
&&
.LONG TERM...
354 AM CDT
SATURDAY NIGHT THROUGH THURSDAY...
FRIDAY THROUGH WEDNESDAY...
NICE WEATHER EXPECTED FRIDAY AS UPPER TROUGH FROM OUR CURRENT
MID-WEEK STORM SYSTEM LIFTS AWAY TO THE NORTHEAST AND LOW
AMPLITUDE SHORT WAVE RIDGE DEVELOPS OVERHEAD. SURFACE HIGH
PRESSURE DRIFTS EAST ACROSS THE CWA DURING THE DAY...WITH
SUBSIDENCE AND DRY COLUMN EXPECTED TO PRODUCE A GOOD DEAL OF
SUNSHINE. LIGHT WINDS IN THE VICINITY OF THE RIDGE AXIS THROUGH
EARLY AFTERNOON SHOULD ALLOW FOR TYPICAL SPRING LAKE BREEZE
DEVELOPMENT...THOUGH 925-950 MB MODEL THERMAL FIELDS INDICATE
INLAND AREAS SHOULD BE ABLE TO REACH HIGHS IN THE 48-52 DEGREE
RANGE. WINDS TURN SOUTHEAST BY EVENING...SETTING UP A SEASONABLY
COOL NIGHT AS MID AND HIGH CLOUDS EVENTUALLY INCREASE FROM THE
WEST AHEAD OF THE NEXT UPSTREAM DISTURBANCE.
THAT DISTURBANCE IS ACTUALLY A COUPLE OF INDIVIDUAL SHORT WAVES
WHICH HELP TO AMPLIFY A BROAD UPPER TROUGH ACROSS THE CENTRAL
CONUS THROUGH THE WEEKEND...ONE MOVING ACROSS THE UPPER
MISSISSIPPI VALLEY SATURDAY WHILE THE OTHER DIGS ACROSS THE
CENTRAL/SOUTHERN PLAINS AND EVENTUALLY INDUCES A DEEPENING AREA OF
LOW PRESSURE OVER THE OHIO VALLEY AND LOWER GREAT LAKES REGION BY
LATE SUNDAY AS IT BEGINS TO SWING NORTHEAST FROM THE BASE OF THE
TROUGH. MODEST HEIGHT FALLS DEVELOP INTO THE AREA SATURDAY MORNING
WITH THE APPROACH OF THE NORTHERN WAVE...THOUGH LOW LEVEL MOISTURE
RETURN IS LIMITED TO A NARROW CORRIDOR AHEAD OF THE COLD FRONT
WHICH TRAILS THE SURFACE LOW PRESSURE REFLECTION OVER WISCONSIN.
THUS PRECIP POTENTIAL DURING THE DAY SATURDAY LOOKS TO BE FOCUSED
ACROSS THE WESTERN HALF OF THE CWA AND PRIMARILY MIDDAY INTO THE
AFTERNOON WITH THE ADVANCING COLD FRONT. DESPITE INCREASING MID-
HIGH CLOUD COVER...SOUTH WINDS SHOULD HELP WARM TEMPS INTO THE 50S
OVER MUCH OF THE AREA AND TO AROUND 60 ACROSS THE SOUTH.
WRF...WHICH IS SLOWER WITH THE FRONT...INDICATES A BIT OF A
SOUTHEAST COMPONENT ALONG THE IL LAKESHORE WHICH MAY INDICATE A
VERY WEAK LAKE BREEZE.
FRONT PUSHES EAST ACROSS THE AREA SATURDAY EVENING...THOUGH
LATEST MODEL RUNS REALLY SCALE BACK PRECIP DURING THE EVENING AS
THE STRONGER SYNOPTIC FORCING BECOMES SPLIT TO OUR NORTH AND WELL
TO THE SOUTH. AS THE SOUTHERN LOW BEGINS TO DEVELOP AND DEEPEN
LATE SATURDAY NIGHT...FRONTOGENETIC FORCING ALONG THE SOUTH END OF
THE FRONT INCREASES AND ALLOWS RAIN TO DEVELOP FROM THE SOUTHWEST
INTO PARTS OF THE CWA BY SUNDAY MORNING. MEDIUM-RANGE GUIDANCE
REMAINS A LITTLE DIFFERENT WITH THE EXACT LOW TRACK ACROSS THE
MIDWEST SUNDAY/SUNDAY NIGHT...THOUGH GENERALLY FOCUS PRECIP ACROSS
THE SOUTHEAST HALF TO TWO THIRDS OF THE FORECAST AREA. PARTIAL
THICKNESS FIELDS INDICATE NEARLY ALL OF THE PRECIP WOULD FALL AS
RAIN...THOUGH THE SLIGHTLY FARTHER NORTHWEST TRACK OF THE 12Z
ECMWF WOULD SUPPORT A BRIEF MIX OR CHANGEOVER TO WET SNOW LATE
SUNDAY NIGHT OR EARLY MONDAY BEFORE PRECIP ENDS. CURRENT MODEL
PROGS GENERATE SOME SUBSTANTIAL QPF TOTALS ACROSS THE SOUTHEAST
PORTION OF THE FORECAST AREA THROUGH SUNDAY NIGHT...FROM 0.50
INCHES IN THE FARTHER SOUTHEAST GFS TO 1.25 INCHES IN THE ECMWF.
RISING HEIGHTS THEN DEVELOP INTO THE AREA MONDAY AS THE UPPER
TROUGH PULLS AWAY TO THE EAST...WITH GOOD MODEL CONSENSUS IN
DEVELOPING BROAD UPPER RIDGE ACROSS THE AREA THROUGH MID-WEEK
BEFORE THE NEXT AMPLIFIED UPPER TROUGH APPROACHES. SURFACE HIGH
PRESSURE OVER THE AREA MONDAY INTO TUESDAY WILL LIKELY SUPPORT
LAKE BREEZES BOTH DAYS...WITH TEMPS MODERATING FROM THE MID-40S TO
MID 50S EAST TO WEST MONDAY AND TO THE 55-60 RANGE ON TUESDAY.
SURFACE LOW DEVELOPING TO THE WEST OF THE AREA BY WEDNESDAY WOULD
SUPPORT CONTINUED SOUTH FLOW AND MILD TEMPS MID-WEEK...THOUGH WITH
AN INCREASING CHANCE OF RAIN.
RATZER
&&
.AVIATION...
FOR THE 12Z TAFS...
A FRONTAL BOUNDARY STRETCHES FROM NEAR VYS TO GYY THIS MORNING
WITH NORTHEASTERLY FLOW AND LIFR CIGS NORTH OF THE BOUNDARY AND
SOUTHERLY WINDS AND HIGHER CIGS SOUTH OF THE FRONT. THE FRONT IS
PROGGED TO LIFT SLIGHTLY NORTH TO NEAR MDW BY MID MORNING THEN
SHOULD STALL AND EVENTUALLY START MOVING SOUTH AGAIN. WITH THAT
IN MIND HAVE ALL THE TERMINALS EXCEPT GYY IN NORTHEAST TO NORTH
FLOW THROUGH THE DAY TODAY WITH LIFR CIGS. DEPENDING ON HOW FAR
NORTH THE BOUNDARY GETS...COULD SEE SOME BREAKS IN THE CLOUDS AND
VARIABILITY IN THE WINDS AT MDW...BUT NOT ENOUGH CONFIDENCE TO PIN
ANYTHING DOWN FOR THE TAF.
SHOWERS CONTINUE TO SPREAD NORTH ACROSS NORTHERN ILLINOIS THIS
MORNING AND WILL BE IN PLACE THROUGH MUCH OF THE MORNING INTO
EARLY/MID AFTERNOON AS LOW PRESSURE MOVES ACROSS THE REGION. SOME
VERY MODEST INSTABILITY IS IN PLACE AHEAD OF THE LOW...AS FAR
NORTH AS SOUTHERN WISCONSIN WHICH IS RESULTING IN SOME LIGHTNING
ACTIVITY. FOR NOW IT APPEARS THE AXIS OF HIGHEST INSTABILITY LIES
ALONG AND JUST NORTH OF THE STATE LINE SO WILL KEEP TS OUT OF THE
TAF FOR NOW BUT CERTAINLY CANNOT RULE OUT THE POSSIBILITY TO HAVE
AN EMBEDDED THUNDERSTORM MOVE OVER ONE OF THE TERMINALS. AS THE
LOW PASSES BY MID AFTERNOON...WINDS WILL BACK TO THE NORTH-
NORTHWEST AND BECOME GUSTY. WHILE THIS SHOULD HELP INCREASE CIGS
SLIGHTLY TO HIGHER END IFR...THERE WILL ALSO BE A WINDOW WHEN
MIXED PRECIP OR SNOW IS POSSIBLE. LIGHT ACCUMULATIONS ARE POSSIBLE
FOR RFD WHICH WILL BE DEEPER IN THE COLD AIR. FOR THE CHICAGO
TERMINALS...DRY AIR MOVING IN ALOFT MAY RESULT IN SNOW/DRIZZLE OR
JUST DRIZZLE BEFORE PRECIP ENDS ALTOGETHER THIS EVENING. HIGH
PRESSURE WILL BUILD ACROSS THE AREA ON FRIDAY WHICH SHOULD HELP
IMPROVE CONDITIONS TO VFR AND PROVIDE LIGHT FLOW...ALTHOUGH AN
AFTERNOON LAKE BREEZE IS POSSIBLE.
BMD
&&
.MARINE...
315 AM CDT
MODERATELY STRONG NORTHEASTERLY WINDS OF 30 TO 35 KT ARE IN PLACE
OVER MUCH OF LAKE MICHIGAN EARLY THIS MORNING AHEAD OF AN AREA
OF LOW PRESSURE OVER NORTHERN MISSOURI. WEAKER FLOW IS IN PLACE
ACROSS THE FAR SOUTHERN END OF LAKE MICHIGAN WHERE A FRONTAL
TROUGH IS IN PLACE. THE LOW WILL MOVE JUST SOUTH OF LAKE MICHIGAN
THIS AFTERNOON WITH WINDS BACKING TO THE NORTH AND GALES SPREADING
SOUTH ACROSS THE REMAINDER OF THE LAKE. GALES SHOULD DIMINISH
TONIGHT AND WINDS WILL BECOME LIGHT ON FRIDAY AS A RIDGE AXIS
MOVES OVER THE LAKE. FRESH SOUTHERLY FLOW RESUMES LATE FRIDAY INTO
SATURDAY AS THE RIDGE DEPARTS TO THE EAST ANOTHER FRONT MOVES
ACROSS LAKE MICHIGAN SATURDAY NIGHT INTO SUNDAY TURNING WINDS
NORTH AGAIN.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP TO WILMETTE HARBORS UNTIL 4 PM THURSDAY.
GALE WARNING...LMZ740-LMZ741-LMZ742-LMZ743-LMZ744-LMZ745-LMZ777-
LMZ779...4 PM THURSDAY TO 4 AM FRIDAY.
&&
$$
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
1117 AM CDT THU MAR 24 2016
.UPDATE...
Issued at 1113 AM CDT Thu Mar 24 2016
Surface low making its way across Central Illinois this morning,
dragging showers and scattered thunder with it. Forecast going
well overall with the timing of the precip. Showers on the back
side of the low limited in hi res models. Gusty winds following
the low as it deepens and tightens the pressure gradient. Cooler
afternoon with gusty winds anticipated and on track. No major
updates anticipated...but some small adjustments here and there
for hourly trends.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 323 AM CDT Thu Mar 24 2016
08z/3am surface analysis shows 997mb low over northern Missouri,
with stationary frontal boundary extending into north-central
Illinois. Based on latest obs, it appears the boundary extends from
near Macomb to just north of Pontiac. To the south of the front in
the warm sector, much of the KILX CWA has current temps in the lower
60s. Meanwhile to the north of the boundary, readings are only in
the lower 40s in Galesburg. A broken line of convection associated
with the approaching low developed across eastern Kansas/western
Missouri last evening...however that activity diminished as it
tracked northeastward and skirted the NW CWA around midnight. Latest
radar imagery shows very little going on across central Illinois:
however, showers are beginning to develop upstream and should spread
into the area over the next couple of hours. HRRR has been quite
persistent showing the showers becoming more widespread along/west
of I-55 after 09z/4am. As the low and accompanying cold front get
closer, showers and a few thunderstorms will develop across the
entire area early this morning. Have therefore carried categorical
PoPs across the board. The low will track to near the Chicago area
by midday, pulling the cold front through central Illinois and
pushing the widespread rain into Indiana at that time. Have
therefore lowered PoPs to just low chance across most of the area
this afternoon. The exception will be northwest of the Illinois
River, where deformation zone rain and snow showers will persist
through the afternoon. High temperatures will be achieved early in
the day, with readings falling steadily this afternoon. By mid
afternoon, temps will range from the upper 30s northwest of the
Illinois River...to the middle 50s near the Indiana border.
.LONG TERM...(Friday through Wednesday)
ISSUED AT 323 AM CDT Thu Mar 24 2016
As low pressure continues to lift into the eastern Great Lakes, a
few rain/snow showers may linger along/north of the I-74 corridor
early this evening before coming to an end before midnight. Skies
will initially be overcast, but will clear from west to east
overnight with lows dropping into the upper 20s and lower 30s. High
pressure will build into the region on Friday, leading to mostly
sunny and cool conditions with highs in the lower to middle 50s.
Once the high shifts off to the east, the next system will begin to
approach from the west over the weekend. Models have been
struggling with this feature for the past several days, and
agreement remains poor with the 00z Mar 24 run. The main issues
have been how much and how quickly an approaching short-wave trough
will amplify. Given the progressive flow pattern, have generally
preferred the weaker and faster solution. As such, will continue to
feature highest rain chances Sunday/Sunday night...followed by a
return to dry weather for Monday and Tuesday.
&&
.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 545 AM CDT Thu Mar 24 2016
A large area of showers and isold tsra was tracking across the
forecast area this morning and will affect the cigs and vsbys
for a time as we head into early afternoon. Cigs have been
generally VFR overnight but with rain moving across the area
we expect at least some tempo MVFR cigs and vsbys in the heavier
areas of rain. Once the cold front pushes across the area...forecast
soundings suggest an increase in coverage of MVFR cigs as colder
air wraps into central Illinois this afternoon. Surface winds will
be south to southwest this morning at 12 to 17 kts with occasional
gusts up to 30 kts near the heavier showers. We look for winds to
become more southwest by 17z and then shift into the northwest
around 19z at PIA, 21z at SPI and by 01z at CMI. Once the MVFR
cigs move in behind the cold front, it appears they will linger
thru at least the evening hours, if not longer, based on the
latest forecast soundings.
&&
.ILX Watches/Warnings/Advisories...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...Barnes
LONG TERM...Barnes
AVIATION...Smith
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
229 PM EDT THU MAR 24 2016
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY|/...
ISSUED AT 955 AM EDT THU MAR 24 2016
1345Z UPDATE...CHANGES WERE MADE TO REFLECT THE CURRENT RADAR
MOSAIC WHICH SHOWERS A LITTLE FARTHER WIDESPREAD AND OVER MOST OF
THE FORECAST AREA AS OF THIS HOUR. CONVECTION IS LAGGING
BEHIND...HOWEVER CHANCES WILL REMAIN IN THE FORECAST FOR THIS
AFTERNOON BEFORE AND WHILE THE FRONT MOVES THROUGH THE AREA BY
LATE THIS AFTERNOON. STILL KEEPING 90/100 PERCENT POPS OVER THE
MAJORITY OF THE AREA. SOME MINOR TWEAKS WERE MADE TO HIGH
TEMPERATURES TODAY AS MANY OF THE SITE PROBABLY ALREADY HIT THEIR
HIGH TEMPERATURE MARK EARLIER THIS MORNING AND WILL REMAIN STEADY
OR DECLINE. SITES TO THE NORTHWEST SUCH AS LAF...WHICH MAY SEE
SOME CLEARING LATE THIS AFTERNOON BEHIND THE PRECIP COULD SEE
TEMPERATURE BRIEFLY REBOUND HERE INTO THE LOW 60S. SO LEFT
TEMPERATURE FORECAST AS IS FOR THIS AREA RIGHT NOW. OTHERWISE NO
OTHER MAJOR UPDATES WERE NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS...
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 220 PM EDT THU MAR 24 2016
LONG TERM MODELS SHOW SOME DISAGREEMENT EARLY IN THE LONG TERM ON
TIMING AND STRENGTH OF AN UPPER WAVE AND ASSOCIATED FRONTAL
SYSTEM. THE GFS IS WEAKER AND FASTER WITH THIS FEATURE WHILE THE
ECMWF IS SLOWER AND STRONGER...HOLDING ONTO RAIN OVER THE AREA
INTO MONDAY. INITIALIZATION HELD ONTO LIKELY POPS FOR SUNDAY NIGHT
AND CARRIED CHANCES INTO MONDAY AND THOUGHT THIS WAS A GOOD
COMPROMISE WITH A NUDGE TOWARD THE ECMWF WHICH HAS HAD BETTER
CONSISTENCY WITH THIS FEATURE. BY MONDAY NIGHT THOUGH BOTH MODELS
LINE UP AGAIN WITH RIDGING OVER THE AREA AND DRY WEATHER IN PLACE
THROUGH THE DAY ON WEDNESDAY. MONDAY NIGHT CURRENTLY
INITIALIZATION LOW TEMPERATURES ARE ABOVE FREEZING BUT THIS MAY
NEED TO BE MONITORED FOR FROST/FREEZE POTENTIAL AS WE GET CLOSER.
HIGHS LOOK LIKE THEY/LL WARM BACK INTO THE 60S FOR WEDNESDAY AND
THURSDAY AHEAD OF A FRONTAL SYSTEM THAT COULD MOVE IN TO THE AREA
BRINGING RAIN CHANCES WITH IT FOR WEDNESDAY NIGHT ON. WITH LESS
CERTAINTY ON TIMING OF MID/END OF WEEK FRONTAL SYSTEM DECREASED
INITIALIZATION POPS FROM LIKELY TO CHANCE.
&&
.AVIATION /DISCUSSION FOR 241800Z TAF ISSUANCE/...
ISSUED AT 110 PM EDT THU MAR 24 2016
SITES WILL HAVE VARIABLE CEILINGS OVER THE NEXT FEW HOURS AS SOME
SHOWERS WITH EMBEDDED THUNDERSTORMS MOVE THROUGH AND THEN POSSIBLE
BREAK FOLLOWED BY A LINE OF SHOWERS AND STORMS PASSING AHEAD OF A
COLD FRONT. EXPECT TO SEE BOUNCING AROUND FROM VFR TO MVFR AND IFR
WITHIN SHOWERS FROM NOW UNTIL FRONTAL PASSAGE AROUND 20-23Z. THIS
LINE COULD BRING WITH IT SOME STRONGER WIND GUSTS AND HAVE
INCLUDED THESE IN A TEMPO GROUP. AFTER THE FRONT PASSES EXPECT TO
SEE CEILINGS RISE FOR A FEW HOURS BEFORE DROPPING BACK TO MVFR AND
THEN LOW END MVFR DURING THE OVERNIGHT. WIND GUSTS COULD PICK UP
IN THE DRY SLOT AROUND THE FRONT BUT THEN SHOULD DECREASE IN SPEED
TONIGHT. SOUNDINGS INDICATE GUSTS WILL CONTINUE THROUGH THE NIGHT
THOUGH AS LOW PRESSURE PULLS AWAY BUT WILL DROP TO AROUND 18-22
KTS AND DROP OFF COMPLETELY BETWEEN 12-15Z FRIDAY AS HIGH PRESSURE
BUILDS IN.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....CP
AVIATION...CP
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
208 PM EDT THU MAR 24 2016
.SYNOPSIS...
ISSUED AT 200 PM EDT THU MAR 24 2016
A DISTURBANCE WILL INTERACT WITH A FRONTAL BOUNDARY ACROSS THE
AREA TO PRODUCE WIDESPREAD RAIN SHOWERS ALONG WITH A FEW
THUNDERSTORMS THROUGH THIS AFTERNOON. GUSTY SOUTH WINDS ARE
EXPECTED IN ADVANCE OF THE COLD FRONT WITH THIS SYSTEM...
PARTICULARLY ACROSS FAR NORTHEAST INDIANA AND NORTHWEST OHIO
TODAY. CLOUDS WILL DIMINISH ON FRIDAY WITH COOLER TEMPERATURES.
LOW TEMPERATURES TONIGHT WILL DROP INTO THE LOWER TO MID 30S.
HIGHS ON FRIDAY WILL ONLY BE IN THE 40S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM EDT THU MAR 24 2016
STALLED SURFACE BOUNDARY REMAINS SPRAWLED FROM FAR NORTHERN INDIANA
INTO FAR NORTHWEST OHIO THIS MORNING. BROAD ISENTROPIC LIFT/MOISTURE
ADVECTION CONTINUES IN ASSOCIATION WITH THIS BOUNDARY AND HAS
LARGELY BEEN RESPONSIBLE FOR WIDESPREAD RAIN SHOWERS/DRIZZLE ACROSS
PRIMARILY NORTHERN HALF OF THE FORECAST AREA DURING THE OVERNIGHT
HOURS. EXPECTING THAT SOME DIMINISHMENT IN RAIN SHOWER COVERAGE WILL
OCCUR ACROSS THE NORTH DURING THE EARLY-MID MORNING HOURS AS MORE
FAVORED ZONE OF ISENTROPIC ASCENT PER 295K-300K LAYER PROGS LIFTS
NORTHWARD ACROSS CENTRAL LOWER MICHIGAN. RAIN POTENTIAL TO RAMP
UP FROM WEST TO EAST FROM MID MORNING THROUGH THE AFTERNOON AS
POTENT PV ANOMALY OVERSPREADS MID MS VALLEY/SOUTHERN GREAT LAKES
ALONG WITH A CORRESPONDING DOWNSTREAM LOW/MID LEVEL FGEN RESPONSE.
SOME WEAK ELEVATED INSTABILITY IS NOTED PER SPC RUC ANALYSIS AT
06Z ACROSS THE FAR NORTH...BUT PRIMARY INSTABILITY AXIS OF NOTE
FOR LOCAL AREA WILL BE IMMEDIATELY PRECEDING SFC COLD FRONTAL
BOUNDARY THIS AFTERNOON WITH SOME DIFFERENTIAL THERMAL ADVECTION
SETTING UP THIS NARROW CORRIDOR OF INSTABILITY. MAGNITUDE OF
INSTABILITY IS EXPECTING TO BE ON THE MARGINAL SIDE...GENERALLY IN
THE 500-800 J/KG RANGE...BUT A BRIEF POTENTIAL OF NEAR SFC/SFC
BASED INSTABILITY MAY EXIST ACROSS SOUTHEAST HALF OF THE AREA LATE
MORNING-LATE AFTERNOON. THIS WEAK INSTABILITY COMBINED WITH FAIRLY
IMPRESSIVE DEEP LAYER SHEAR MAGNITUDES OF 50-60 KNOTS DOES POSE
SOME CONCERN FOR SMALL LINEAR BOWING SEGMENTS. THIS THREAT REMAINS
HIGHLY CONDITIONAL ON INSTABILITY AND OVERALL SEVERE THREAT
REMAINS LOW. NOT MUCH CHANGE FROM PREVIOUS FORECAST THINKING WITH
ISOLD SEVERE POTENTIAL AT BEST TODAY GIVEN LIMITED
INSTABILITY...WITH ISOLATED STRONGER WIND GUSTS AS THE MAIN
THREAT.
TEMPERATURE FORECAST REMAINS A CHALLENGING ONE IN THE NEAR
TERM...WITH A 20 DEGREE NORTH TO SOUTH TEMPERATURE DIFFERENTIAL
ACROSS THE FORECAST AREA THIS MORNING. SFC BOUNDARY HAS REMAINED
SOMEWHAT STUBBORNLY ANCHORED ACROSS FAR NORTHERN INDIANA...BUT
SHOULD START TO SEE SOME NORTHWARD RETREAT OF THIS BOUNDARY IN THE
09Z-15Z TIMEFRAME. THIS SHOULD PUT BULK OF FORECAST AREA IN WARM
SECTOR...ALBEIT FOR A VERY BRIEF TIME ACROSS THE FAR NORTHWEST AS
SFC REFLECTION REACHES NORTHWEST INDIANA LATE MORNING. OVERALL NOT
MUCH CHANGE TO INHERITED MAX TEMPS...WITH JUST A SLIGHT UPWARD
ADJUSTMENTS INTO THE MID 60S FAR SOUTH CENTRAL/EAST WHERE RESIDENCE
TIME OF WARM SECTOR WILL BE PROLONGED...AND WHERE A MORE DELAYED
PRECIP TIMING IS ANTICIPATED. ANOTHER LOWER END CONCERN TODAY WILL
BE A BRIEF POTENTIAL OF NEAR ADVISORY OR ADVISORY LEVEL SOUTH-
SOUTHWEST WINDS AHEAD OF THIS SYSTEM. SFC REFLECTION SHOULD BE IN A
SLIGHT DEEPENING MODE THIS AFTERNOON WITH AN AXIS OF FAIRLY
STRONG SFC PRESSURE FALLS EXPECTED TO DEVELOP/MIGRATE ACROSS
SOUTHEAST LOWER MICHIGAN. THESE PRESSURE FALLS COMBINED WITH
POTENTIALLY BETTER MIXING WHERE SFC TEMPS ARE EXPECTED TO REACH
THE MID 60S...COULD ALLOW FOR A BRIEF WINDOW OF 35 TO 45 MPH WIND
GUSTS ACROSS THE FAR EAST IN THE 16Z-21Z TIMEFRAME GIVEN STRONG
LOW LEVEL WIND FIELD. HAVE HELD OFF ON ANY WIND ADVISORY AT THIS
TIME GIVEN LOW CONFIDENCE ON DEPTH OF MIXING AND RELATIVELY SHORT
DURATION OF THIS POTENTIAL.
DRY SLOT TO OVERSPREAD THE AREA TONIGHT AS COLDER AIR ADVECTS
SOUTHEASTWARD BEHIND THE FRONT DIMINISHING PRECIP COVERAGE IN THE
EVENING...ALTHOUGH DEFORMATION ZONE MAY PROLONG AT LEAST SCATTERED
SHOWERS ACROSS THE FAR NORTHWEST. ANY CHANGEOVER TO SNOW SHOULD BE
OF MINIMAL PRECIP COVERAGE/INTENSITY AND NO SNOW ACCUMULATION IS
ANTICIPATED AT THIS TIME. END OF THIS PRECIP EVENT COULD TURN OUT
TO BE MORE DRIZZLY IN NATURE TONIGHT...BUT CURRENTLY NOT EXPECTING
ANY SIGNIFICANT IMPACTS FROM POTENTIAL DRIZZLE OR FREEZING DRIZZLE
TONIGHT.
&&
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 342 AM EDT THU MAR 24 2016
MUCH MORE BENIGN WEATHER ANTICIPATED FOR FRIDAY AND SATURDAY. ANY
RESIDUAL RN/SN SHOWERS WILL BE QUICKLY CUT OFF BY 12Z AS SHORTWAVE
RIDGE AND ASSOCIATED BUBBLE OF SUBSIDENCE/SURFACE HIGH PRESSURE FOLD
INTO THE GREAT LAKES. SHOULD BE MOSTLY SUNNY BY AFTERNOON AS
NEGATIVE THETA-E ADVECTION FINALLY ERODES THIN LAYER OF MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION IN CAA REGIME. HIGH TEMPS WILL
MAKE A RUN AT UPPER 40S BY LATE AFTERNOON AS WINDS START TO BACK.
LOW 50S MAY EVEN BE POSSIBLE IF MORNING CLOUDS DISSIPATE QUICKER
THAN EXPECTED. MUCH WARMER CONDITIONS FOR SATURDAY AS SW FLOW/WAA
RAMP UP AHEAD OF NEXT WAVE. UPPER 50S TO NEAR 60F POSSIBLE GIVEN
850MB TEMPS AROUND 4C...BUT THE TRADEOFF WILL BE INCREASING HIGH-
BASED CLOUDS ESPECIALLY IN OUR NORTHWEST BY AFTERNOON AS MIDLEVEL
WARM/MOIST AIR ADVECTION INCREASES.
NEXT CHANCE OF RAIN WILL ARRIVE EARLY SUNDAY MORNING AS ANOTHER
VIGOROUS SHORTWAVE RIPPLES THROUGH THE REGION. STILL SOME
INCONSISTENCIES AMONG THE LATEST DETERMINISTIC GUIDANCE TO WORK OUT.
HOWEVER DOES APPEAR TO BE SOME CONSENSUS FOR SURFACE WAVE
DEVELOPMENT ALONG BAROCLINIC ZONE WITH DECENT SHOT OF SOME MODERATE
RAIN AS MIDLEVEL TROUGH TAKES ON AT LEAST A NEUTRAL TILT. BEST
PRECIP CHANCES LOOK TO BE SUNDAY AFTERNOON INTO SUNDAY NIGHT.
THERMAL PROFILES SHOULD BE WARM ENOUGH FOR ALL RAIN...THOUGH IT IS
WORTH NOTING THE ECMWF SOLUTION WOULD SUPPORT THE POSSIBILITY OF A
FEW WET SNOWFLAKES MIXING IN ON BACK EDGE OF EXITING DEFORMATION
BAND. STILL PLENTY OF TIME TO WATCH THIS EVENT AND SUSPECT THERE
WILL BE CHANGES SINCE PARENT JET ENERGY IS STILL OVER THE NORTH
PACIFIC. QUIET WEATHER THEREAFTER AS SPRAWLING MID/UPPER RIDGE AND
SURFACE HIGH MOVE OVER THE REGION. COOL AT FIRST BUT SHOULD WARM UP
AGAIN BY MIDWEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 202 PM EDT THU MAR 24 2016
TIMING OF LACKLUSTER CONVECTION INTO KSBN IN 20-22 UTC WINDOW.
LESS CERTAINTY OF CONVECTION HOLDING TOGETHER THROUGH THE LATER
EVENING HOURS DUE TO LACK OF SIGNIFICANT DOWNSTREAM
DESTABILIZATION. BEST CHC FOR IFR CIGS AT KSBN AS WELL IN CLOSER
PROXIMITIY TO DEEP WRAPPED MOISTURE NW OF SURFACE LOW TRACK.
OTHERWISE LONG DURATION FUELING/ALTERNATE CRITIERA FOR NORTHERN
INDIANA...TURNING DECIDEDLY VFR TOWARD END OF FORECAST PD AS DRY
AIR ADVECTION AND SUBSIDENCE BRING AT LEAST PARTIAL
CLEARING/SCATTER OUT OF STRATOCU DECK.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...GALE WARNING FROM 8 PM THIS EVENING TO 5 AM EDT FRIDAY FOR
LMZ043-046.
&&
$$
SYNOPSIS...MURPHY
SHORT TERM...MARSILI
LONG TERM...AGD
AVIATION...MURPHY
VISIT US AT WW.WEATHER.GOV/IWX
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
117 PM EDT THU MAR 24 2016
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 329 AM EDT THU MAR 24 2016
A STRONG COLD FRONT WILL SWEEP ACROSS CENTRAL INDIANA LATER TODAY
WITH RAIN AND SCATTERED THUNDERSTORMS. MUCH COOLER AIR WILL BUILD IN
TONIGHT AS HIGH PRESSURE ARRIVES FROM THE WEST. AFTER A COOL DAY
FRIDAY...WARMER TEMPERATURES WILL RETURN FOR THE WEEKEND ALONG WITH
A THREAT FOR RAIN SUNDAY AND MONDAY. SEASONABLE TEMPERATURES AND
DRY WEATHER IS EXPECTED THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY|/...
ISSUED AT 955 AM EDT THU MAR 24 2016
1345Z UPDATE...CHANGES WERE MADE TO REFLECT THE CURRENT RADAR
MOSAIC WHICH SHOWERS A LITTLE FARTHER WIDESPREAD AND OVER MOST OF
THE FORECAST AREA AS OF THIS HOUR. CONVECTION IS LAGGING
BEHIND...HOWEVER CHANCES WILL REMAIN IN THE FORECAST FOR THIS
AFTERNOON BEFORE AND WHILE THE FRONT MOVES THROUGH THE AREA BY
LATE THIS AFTERNOON. STILL KEEPING 90/100 PERCENT POPS OVER THE
MAJORITY OF THE AREA. SOME MINOR TWEAKS WERE MADE TO HIGH
TEMPERATURES TODAY AS MANY OF THE SITE PROBABLY ALREADY HIT THEIR
HIGH TEMPERATURE MARK EARLIER THIS MORNING AND WILL REMAIN STEADY
OR DECLINE. SITES TO THE NORTHWEST SUCH AS LAF...WHICH MAY SEE
SOME CLEARING LATE THIS AFTERNOON BEHIND THE PRECIP COULD SEE
TEMPERATURE BRIEFLY REBOUND HERE INTO THE LOW 60S. SO LEFT
TEMPERATURE FORECAST AS IS FOR THIS AREA RIGHT NOW. OTHERWISE NO
OTHER MAJOR UPDATES WERE NEEDED AT THIS TIME. PREVIOUS DISCUSSION
FOLLOWS...
OTHER THAN A FEW SHOWERS DRIFTING ACROSS NORTHWEST PORTIONS OF THE
FORECAST AREA...BEEN A RELATIVELY QUIET NIGHT SO FAR ACROSS CENTRAL
INDIANA. MOSTLY CLOUDY SKIES WITH BREEZY SOUTHWEST WINDS CONTINUED
AND TEMPS HAD FALLEN LITTLE AS A RESULT. 07Z TEMPS RANGED FROM THE
UPPER 50S TO MID 60S.
THREAT FOR RAIN AND LOCALLY STRONG CONVECTION REMAINS THE PRIMARY
FOCUS FOR TODAY...WITH GUSTY GRADIENT WINDS AND TEMPS SERVING AS
SECONDARY ISSUES.
SURFACE LOW CURRENTLY OVER NORTHWEST MISSOURI EARLY THIS MORNING
WITH A WARM FRONT ARCING EAST INTO THE LOWER GREAT LAKES AND A COLD
FRONT TRAILING S/SW INTO EAST TEXAS. RAIN AND CONVECTION HAS LARGELY
BEEN CONFINED IN CLOSE PROXIMITY TO THE BOUNDARIES WITH WARM
ADVECTION ENHANCED ISOLATED SHOWERS MOVING ACROSS NORTHWEST COUNTIES
AND AIDED BY A POCKET OF STRONGER WINDS AT 850MB. THAT LITTLE JETLET
HAS SHIFTED NORTHEAST OF THE REGION AND WITH LITTLE IN THE WAY OF
FORCING ALOFT PRESENT...EXPECT ONLY ISOLATED LIGHT SHOWERS OVER
WESTERN COUNTIES FOR THE REST OF THE OVERNIGHT HOURS.
AN INCREASING GULF FETCH WILL ADVECT DEEPER MOISTURE NORTH INTO THE
REGION AFTER DAYBREAK WITH RAIN AND A FEW THUNDERSTORMS INCREASING
IN COVERAGE FROM THE WEST THROUGH THE MORNING HOURS. WRF/HRRR SEEM
TO HAVE A NICE HANDLE ON THE CONVECTION SO FAR AND WERE LARGELY
UTILIZED FOR TIMING THE ONSET OF PRECIP WHICH SHOULD PRIMARILY BE
CONFINED TO THE WESTERN HALF OF THE FORECAST AREA THROUGH MIDDAY.
THE NAM AND HRRR BOTH STARTING TO CATCH ONTO THE IDEA OF THE INITIAL
AREA OF RAIN AND STORMS WILL BE ASSOCIATED WITH A PREFRONTAL SURFACE
TROUGH WHICH WILL SWING ACROSS THE FORECAST AREA IN THE EARLY
AFTERNOON. THE COLD FRONT ITSELF WILL TRAIL THE TROUGH BY A FEW
HOURS AND WITH A NARROW AXIS OF INSTABILITY AHEAD OF THE FRONT...
POTENTIAL FOR A THIN CONVECTIVE LINE TO DEVELOP AND TRACK ACROSS THE
REGION DURING THE SECOND HALF OF THE AFTERNOON. WITH AN ABUNDANCE OF
BL SHEAR AND STRONG FORCING ALOFT WITH AN UPPER JET OVERHEAD...BEST
THREAT FOR STRONG STORMS ARE LIKELY TO BE ASSOCIATED WITH THIS LINE.
GUSTY WINDS WOULD BE THE PRIMARY CONCERN WITH 60KTS PROGGED AT
850MB. THE CONVECTIVE LINE SHOULD BE EAST OF THE FORECAST AREA BY 21-
22Z WITH A FEW LINGERING LIGHT SHOWERS IN ITS WAKE.
MODEL SOUNDING ANALYSIS SUGGESTIVE THAT GRADIENT WINDS OUTSIDE OF
STORMS WILL PEAK AT 35 TO 40 MPH THIS AFTERNOON...MAYBE EVEN
SLIGHTLY HIGHER OVER THE EASTERN HALF OF THE FORECAST AREA WHERE THE
LOW LEVEL JET WILL LINGER THE LONGEST AND POTENTIAL EXISTS FOR
HIGHER MIXING LEVELS.
TEMPS...WITH A SLOWER FRONTAL PASSAGE AND SUCH A WARM START THIS
MORNING WITH THE STRONG WARM ADVECTION...EXPECT TEMPS TO GET WARMER
TODAY THAN PREVIOUS THOUGHT. HRRR LOOKED A TAD AGGRESSIVE WITH
WARMING CONSIDERING CLOUD COVER...BUT THE MODEL IS DOING A DECENT
JOB CAPTURING CURRENT TEMPS AND LIKED ITS OVERALL TIMING FOR MAX
TEMPS LATER TODAY. TEMPS WILL REMAIN STEADY IF NOT RISE THE REST OF
THE OVERNIGHT WITH HIGHS BEING REACHED IN THE EARLY AFTERNOON.
GENERALLY WENT LOW TO MID 60 FROM WEST TO EAST WITH POTENTIAL FOR
UPPER 60S OVER FAR EASTERN COUNTIES.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 329 AM EDT THU MAR 24 2016
FORECAST CHALLENGES FOCUS ON LINGERING LIGHT PRECIP CHANCES
TONIGHT...CLOUDS ON FRIDAY AND TEMPS THROUGHOUT THE SHORT TERM.
RAIN AND CONVECTION WILL BE EAST OF THE FORECAST AREA BY 00Z TONIGHT
BUT TRAILING UPPER WAVE WILL BRING WRAPAROUND MOISTURE BACK ACROSS
THE REGION THROUGH THE FIRST HALF OF THE NIGHT. ANY PRECIP SHOULD BE
SCATTERED AND LIGHT AT BEST...WITH ONLY A SMALL POTENTIAL FOR A FEW
SNOWFLAKES TO MIX IN AFTER 06Z AS THE COLDEST AIR LIKELY LAGS THE
DEEPER MOISTURE. BEST CHANCE TO SEE ANY SNOWFLAKES WOULD BE NORTHEAST
OF THE INDY METRO.
SURFACE RIDGE WILL QUICKLY ARRIVE IN WAKE OF THE UPPER WAVE BY
FRIDAY MORNING WITH HIGH PRESSURE BECOMING THE PRIMARY INFLUENCE FOR
MUCH OF THE REST OF THE SHORT TERM. AS DRIER AIR AND SUBSIDENCE
ALOFT BUILDS IN THOUGH...MODEL SOUNDINGS AND RH PROGS CAPTURING A
TRAPPED SHALLOW LAYER OF MOISTURE UNDERNEATH A SHARPENING INVERSION.
THE NAM HINTED AT THIS IDEA ON ITS 00Z RUN WEDNESDAY AND IT HAS
ADDITIONAL SUPPORT WITH THE 00Z RUNS THIS MORNING THAT LEND HIGHER
CONFIDENCE AT A STUBBORN STRATUS/STRATOCU DECK LINGERING WITHIN THE
COLD ADVECTION FRIDAY MORNING. HAVE INCREASED CLOUD COVER
SUBSTANTIALLY AS A RESULT WITH A GRADUAL CLEARING FROM THE WEST INTO
THE EARLY AFTERNOON THE STRATUS MIXES OUT INTO A CU FIELD WHICH
SHOULD GRADUALLY DIMINISH BY LATE DAY.
MAINLY CLEAR SKIES ARE EXPECTED FOR FRIDAY NIGHT AND MUCH OF
SATURDAY AS THE HIGH PRESSURE RIDGE SHIFTS EAST AND SURFACE FLOW
GRADUALLY VEERS BACK AROUND TO A SOUTHEASTERLY DIRECTION BY SATURDAY
EVENING. SOUTHWEST FLOW ALOFT WILL DEVELOP WITH MOISTURE POOLING
NORTH INTO THE LOWER GREAT LAKES SATURDAY NIGHT AHEAD OF A WEAK
BOUNDARY. MAY SEE A FEW SHOWERS SNEAK INTO THE NORTHERN WABASH
VALLEY PRIOR TO DAYBREAK SUNDAY BUT IN GENERAL...THE IMPACTS FROM
THE BOUNDARY AND A DEVELOPING WAVE TO OUR SOUTHWEST WILL HOLD OFF
UNTIL LATER IN THE DAY ON SUNDAY.
TEMPS...GENERALLY TRENDED A DEGREE OR TWO BELOW THE WARMER MAVMOS
FOR FRIDAY HIGHS WITH THE POTENTIAL FOR EXTENSIVE CLOUDS TO LINGER
THROUGH THE FIRST HALF OF THE DAY. SHOULD SEE A NICE RECOVERY IN
TEMPS SATURDAY WITH THE AID OF LOW LEVEL WARM ADVECTION. HARD TO
ARGUE WITH THE WARMER MAVMOS AS HIGHS SHOULD MAKE IT INTO THE LOW
AND MID 60S.
LOW LEVEL THERMAL ANALYSIS SUPPORTED LOWS IN THE LOW TO MID 30S
TONIGHT WHICH LINED UP CLOSER TO THE WARMER MAVMOS. WINDS REMAINING
AT 10-20MPH OVERNIGHT WILL MITIGATE ANY FROST CONCERNS OVER SOUTHERN
COUNTIES WHERE THE FROST/FREEZE SEASON HAS BEGUN FOR THE SPRING.
GREATER CONCERN FOR A POTENTIAL FROST ADVISORY IN SOUTHERN COUNTIES
FRIDAY NIGHT AS LOWS IN THE MID 30S WITH LIGHT FLOW AND CLEAR SKIES
ARE SUPPORTIVE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 329 AM EDT THU MAR 24 2016
ENSEMBLES IN GOOD AGREEMENT DURING THIS PERIOD. APPEARS MAIN WEATHER
MAKER WILL BE AN UPPER TROUGH THAT IS EXPECTED TO PASS OVER THE LOCAL
AREA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. WILL KEEP POPS IN THE
FORECAST ON SUNDAY INTO MONDAY TO COVER THIS SYSTEM.
AFTER MONDAY...ENSEMBLES SUGGEST UPPER HEIGHTS WILL RISE OVER THE AREA
AS DEEP TROUGHING DEVELOPS OVER THE ROCKIES. DUE TO THE RISING
HEIGHTS...WILL GO DRY AFTER MONDAY.
&&
.AVIATION /DISCUSSION FOR 241800Z TAF ISSUANCE/...
ISSUED AT 110 PM EDT THU MAR 24 2016
SITES WILL HAVE VARIABLE CEILINGS OVER THE NEXT FEW HOURS AS SOME
SHOWERS WITH EMBEDDED THUNDERSTORMS MOVE THROUGH AND THEN POSSIBLE
BREAK FOLLOWED BY A LINE OF SHOWERS AND STORMS PASSING AHEAD OF A
COLD FRONT. EXPECT TO SEE BOUNCING AROUND FROM VFR TO MVFR AND IFR
WITHIN SHOWERS FROM NOW UNTIL FRONTAL PASSAGE AROUND 20-23Z. THIS
LINE COULD BRING WITH IT SOME STRONGER WIND GUSTS AND HAVE
INCLUDED THESE IN A TEMPO GROUP. AFTER THE FRONT PASSES EXPECT TO
SEE CEILINGS RISE FOR A FEW HOURS BEFORE DROPPING BACK TO MVFR AND
THEN LOW END MVFR DURING THE OVERNIGHT. WIND GUSTS COULD PICK UP
IN THE DRY SLOT AROUND THE FRONT BUT THEN SHOULD DECREASE IN SPEED
TONIGHT. SOUNDINGS INDICATE GUSTS WILL CONTINUE THROUGH THE NIGHT
THOUGH AS LOW PRESSURE PULLS AWAY BUT WILL DROP TO AROUND 18-22
KTS AND DROP OFF COMPLETELY BETWEEN 12-15Z FRIDAY AS HIGH PRESSURE
BUILDS IN.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....JAS
AVIATION...CP
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1136 AM MDT THU MAR 24 2016
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 309 AM MDT THU MAR 24 2016
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS CLOSED
UPPER LOW CENTERED OVER NORTHEAST KS...WITH SHORTWAVE RIDGING
BUILDING ACROSS THE CENTRAL ROCKIES TOWARD THE NORTHERN PLAINS ON
THE BACK SIDE OF THIS SYSTEM. THERE ARE STILL A FEW WEAK PLUMES OF
DEEPER MOISTURE ROTATING AROUND THE BACK SIDE OF THIS SYSTEM JUST
EAST OF OUR CWA. AT THE SURFACE HIGH PRESSURE IS IN PLACE ACROSS
EASTERN COLORADO WITH STRONG SURFACE LOW PRESSURE ACROSS NORTHERN
MISSOURI. TIGHT SURFACE GRADIENT BETWEEN THESE FEATURES IS STILL IN
PLACE ACROSS THE EASTERN 2/3 OF OUR CWA AND IS SLOWLY RETREATING
EASTWARD.
TODAY-TONIGHT...UPPER LEVEL SHORTWAVE TROUGH TRANSITION ACROSS OUR
CWA WITHIN NW FLOW ALOFT WITH WEAK LEE TROUGH BEGINNING TO REDEVELOP
BY LATE THIS AFTERNOON. DRY CONDITIONS ARE EXPECTED WITH MAIN
FORECAST CHALLENGE BEING IMPACTS OF SNOW PACK ON HIGHS/LOWS. GROUND
TEMPERATURES ARE WARM ENOUGH STILL THAT MELTING SHOULD OCCUR FAIRLY
QUICKLY AFTER SUNRISE. POTENTIAL EXISTS FOR HIGHS TO REACH THE 50S
TODAY...HOWEVER LOCATIONS IN OUR NORTH/NORTHWEST MAY STRUGGLE TO
REACH THE LOW 40S IF SNOW PACK LIMITS DIURNAL HEATING. DEEPEST SNOW
PACK IS IN YUMA COUNTY AND THIS IS WHERE I HAVE LEAST CONFIDENCE IN
HIGHS TODAY. LOWS TONIGHT SHOULD DROP FAIRLY QUICKLY...HOWEVER LEE
TROUGH BEGINS TO DEEPEN AS ANOTHER FRONT APPROACHES THE REGION WITH
INCREASING BL WINDS. I LEANED LOW TEMP FORECAST TOWARDS 2M GUIDANCE
(WARMER BLENDS) AS MIXING MAY PREVENT BETTER RADIATIONAL COOLING.
FRIDAY-SATURDAY NIGHT...THE NEXT UPPER LEVEL TROUGH MOVES INTO THE
PLAINS WITH TWO SPLITS OCCURRING FRIDAY AND A FRONTAL PASSAGE DURING
THE DAY FRIDAY OR FRIDAY NIGHT. CONFIDENCE IS NOT PARTICULARLY HIGH
DUE TO VARIANCES IN HOW MODELS SHOW FRONTAL TIMING AND MOISTURE
RETURN BETWEEN THESE SPLIT SHORTWAVE TROUGHS. WHERE PRECIP OCCURS IT
APPEARS THAT TEMP/MOISTURE PROFILES SHOULD SUPPORT MAINLY A SNOW
EVENT. BEST CHANCE FOR PRECIP APPEARS TO BE WHEN THE SOUTHERN
SHORTWAVE ROTATES TROUGH THE PLAINS (LIKELY CENTERED SOUTH OF OUR
FORECAST AREA).
00Z NAM WAS THE STRONGEST ON THIS FEATURE WITH A CLOSED H7 CENTER
PASSING NEAR OUR CWA...HOWEVER 06Z TRACK IS FURTHER SOUTH AND
SLIGHTLY MORE PROGRESSIVE. LATEST ECMWF SHOWS THE H7 LOW CLOSING
OFF FURTHER SOUTHEAST AND DEEPENING OVER EASTERN KS...AND THE GFS
ONLY SHOWS A WEAK OPEN WAVE AT H5/H7. QUITE A BIT OF
VARIANCE...WHICH LOWERS CONFIDENCE IN POTENTIAL IMPACTS.
STRONGEST OVERLAPPING PRECIP SIGNAL IS IN OUR SOUTHERN CWA LATE
FRIDAY NIGHT THROUGH SATURDAY MORNING REGARDLESS OF WHICH MODEL WE
CHOOSE...SO I KEPT CHANCE POPS IN THIS AREA. CONSENSUS FAVORS SNOW
ACCUMULATIONS GENERALLY 1-2" (ASSUMING MAINLY SNOW DURING THE
EVENT). WILL NEED TO CONTINUE MONITORING TRENDS.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 309 AM MDT THU MAR 24 2016
SUNDAY THROUGH TUESDAY WILL BE DRY WITH WARMING TEMPERATURES AS AN
UPPER RIDGE MOVES OVER THE CENTRAL HIGH PLAINS. SURFACE HIGH
PRESSURE MOVES INTO THE SOUTHERN PLAINS AS A LEE TROUGH BEGINS TO
DEEPEN ALONG THE FRONT RANGE MONDAY NIGHT AHEAD OF THE NEXT MAIN
UPPER LOW THAT MOVES INTO THE CENTRAL NEVADA. HIGH TEMPERATURES IN
THE 50S ON SUNDAY WILL WARM INTO THE 70S BY TUESDAY. THE INITIAL
SHORT WAVE TROUGH LIFTS OUT OF THE UPPER LOW ACROSS NORTHEAST
COLORADO AND INTO WESTERN NORTH DAKOTA AND WESTERN NEBRASKA BY MID
DAY WEDNESDAY ALONG WITH A COINCIDENT SURFACE LOW CENTER. THERE IS A
POSSIBILITY OF SHOWERS AND THUNDERSTORMS DEVELOPING OVER THE FAR
EASTERN SECTIONS OF THE FORECAST AREA TUESDAY EVENING INTO EARLY
WEDNESDAY AHEAD OF THE SURFACE THROUGH THAT MOVES EASTWARD.
FROM WEDNESDAY THROUGH THURSDAY MODELS BECOME MORE DIVERGENT ON HOW
THE COMBINATION OF THE UPPER LOW OVER THE WEST AND THE LOW LIFTING
INTO THE NORTHERN PLAINS IS HANDLED. THE GFS TENDS TO SEPARATE
THESE FEATURES MORE WITH THE LOW LIFTING INTO THE NORTHERN PLAINS
MAKING BETTER PROGRESS TOWARDS THE GREAT LAKES REGION THAN THE ECMWF
THAT TENDS TO KEEP THE FEATURES LINKED INTO A SINGLE ELONGATED
TROUGH THAT EXTENDS FROM THE NORTHERN HIGH PLAINS TO OFF THE COAST
OF SOUTHERN CALIFORNIA. EITHER WAY IT APPEARS TEMPERATURES WILL
COOL ACROSS THE CENTRAL HIGH PLAINS REGION WEDNESDAY AND THURSDAY AS
THERE WILL BE A COLD FRONT THAT MOVES ACROSS THE REGION WEDNESDAY
NIGHT WITH A CHANCE OF LIGHT RAIN SHOWERS SPREADING ACROSS THE AREA
...CHANGING TO LIGHT SNOW WEDNESDAY NIGHT...AND BACK TO RAIN ON
THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1126 AM MDT THU MAR 24 2016
VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF PERIOD FOR BOTH KGLD
AND KMCK. LOW LEVEL WIND SHEAR IS EXPECTED TO IMPACT BOTH
TERMINALS FOR A FEW HOURS STARTING AROUND 10Z FRIDAY. THE LLWS
WILL BE AROUND 700FT FOR KGLD AND 1000FT FOR KMCK...BOTH FROM
AROUND 190 DEGREES UP TO 45 KTS. CLOUDS WILL START TO MOVE INTO
THE TAF SITES BETWEEN 05Z AND 10Z...WITH CEILINGS DROPPING DOWN
TO AROUND 10000FT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...CLT
AREA FORECAST DISCUSSION
National Weather Service Dodge City KS
1222 PM CDT THU MAR 24 2016
...Updated Aviation and Synopsis...
.SYNOPSIS...
ISSUED AT 1219 PM CDT THU MAR 24 2016
At 12z Thursday a 500mb Low was located over northwest Missouri.
Further west another, weaker, 500mb trough was located over
Washington and southern British Columbia. Between these two system
a 700mb and 500mb northwest flow was present across the Central
Rockies. at 12z Thursday the 850mb wind at Dodge City was 50
knots. At the surface an area of high pressure was located over
northeast Colorado.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 214 AM CDT THU MAR 24 2016
The upper level low driving all the sensible weather last night will
continue to move away from the forecast region. In the wake, high pressure
will build in. The net result is gradually decreasing wind magnitudes
through the day. The strongest winds is expected right now and winds
by the afternoon should be NNW 10-20 mph. Otherwise, highs today will
be in the 50s with the warmest readings near the Oklahoma border. Other
that light precipitation early this morning, the day will be dry with
pops trending to zero percent. Critical fire weather conditions are
not expected this afternoon as relative humidities will be higher given
the cooler temperatures. For tonight, weak High Plains lee troughing
will developing with a light southerly wind continuing through the overnight.
Mins in the lower 30s are expected.
.LONG TERM...(Friday THROUGH Wednesday)
ISSUED AT 214 AM CDT THU MAR 24 2016
On Friday, a warm air-advection pattern is expected, particularly from
the SE Zones. Compressional warming ahead of a front will send highs
back into the 70s across south-central Kansas. Moisture will be limited
ahead of the front and even any precip is squeezed out, it will be mid
level moisture (a few high based showers). Fairly low confidence in
this happening, although do have high pops out west with the upslope
component to the winds is stronger. A better chance for precip comes
late Saturday and into Sunday as a compact vortmax ejects out. The ECMWF
and NAM indicate accumulating snowfall where the GFS is mainly dry.
Will put more bias towards the EC and have the highest pops along the
Oklahoma border closer to the vortmax and stronger isentropic lift.
Snow amounts are fairly conservative in the grids right now, although
several inches of snow cannot be ruled out given the model QPF trends
from the NAM and ECMWF. The event should start as rain but then transition
to snow as intense cold air advection develops. Beyond that, a drier
forecast is expected with moderating temperatures.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Friday AFTERNOON)
ISSUED AT 1219 PM CDT THU MAR 24 2016
An area of high pressure at the surface will build across western
Kansas this afternoon. Gusty northwest winds mid day will decrease
to 10 knots or less and by 00z Friday. These winds at less than 10
knots will become south southeast overnight as a surface trough of
low pressure begins to develop along the lee of the Rockies. South
winds will increase into the 20 to near 25 knot range after 15z
Friday. RAP and HRRR indicating an increasing in mid to high level
moisture late tonight but these cloud bases later tonight and
Friday will be at or above 10000 ft AGL.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 56 33 68 35 / 0 0 10 20
GCK 57 31 65 33 / 0 0 10 30
EHA 59 32 66 34 / 0 0 10 30
LBL 59 32 68 35 / 0 0 10 20
HYS 51 30 64 34 / 0 0 10 20
P28 57 32 70 39 / 0 0 10 20
&&
.DDC Watches/Warnings/Advisories...
NONE.
&&
$$
SYNOPSIS...Burgert
SHORT TERM...Sugden
LONG TERM...Sugden
AVIATION...Burgert
Area Forecast Discussion
National Weather Service Louisville KY
623 PM EDT THU MAR 24 2016
...Forecast Update...
Updated 622 PM EDT Thu Mar 24 2016
Quick update early this evening to account for the latest storm
trends. Convection has blossomed along the cold front, now pushing
across northern portions of I-65. The storms have remained strong,
but sub-severe given instability continues to remain meager. In
fact, where convection has developed is the location that has yet to
see much in the way of rain so far today so some surface-based
instability has been able to develop. The storms over the next
couple of hours will be capable of producing some small hail and
winds to 45 mph. Can`t rule out a rogue severe cell, but think that
threat has likely already peaked along with the diurnal heating
cycle.
.SHORT TERM (Now through Friday Night)...
Issued at 256 PM EDT Thu Mar 24 2016
The concerns this afternoon will continue to be the potential for
severe weather, as well as gradient wind gusts. Gradient winds have
been gusting mainly in the upper 30s to around 40. However, there
have been some gusts as high as 45 mph. The wind advisory continues
until 23Z, but will continue to monitor gusts as it may be able to
be let go before then.
The rain that has moved across central KY today has helped to
stabilize the area. However, SPC mesoanalysis does show an area of
slight instability across west central KY. In addition the 0-6 km
shear values are around 60 knots across the region. Mesoscale models
do suggest that the instability will spread eastward this afternoon
into western portions of the forecast area before weakening towards
the early evening hours. The HRRR continues to show strengthening of
the line of storms right along the cold front into the evening
hours. All things considered, there is still a slight chance for
some strong to severe storms this afternoon with hail and wind
gusts.
The storms should move out of the area by around 03Z or so with some
light showers continuing across the Bluegrass overnight. Rain should
move out completely by daybreak Friday, with dry conditions
expected Friday night.
Temperatures will fall in the wake of the cold front overnight into
the mid 30s to lower 40s. Despite the low temps, frost formation is
not expected as winds will remain elevated overnight. Highs tomorrow
will be much cooler, in the lower to mid 50s. Lows Friday night will
dip into the mid to upper 30s. With light winds and high pressure,
some frost will be possible early Saturday morning.
.LONG TERM (Saturday through Thursday)...
Issued at 305 PM EDT Thu Mar 24 2016
Saturday will remain dry with high pressure ridging in from the
northeast. Temperature will warm into the 60s under mostly sunny
skies. Lows Saturday night will be much warmer, in the 40s areawide.
A trough will dig into the Plains on Sunday and cross the lower Ohio
Valley Sunday night. The best chance for showers and thunderstorms
with this system still looks to be late Sunday afternoon into Sunday
night. Given the dry weather for much of the day ahead of this
system, temperatures will warm into the upper 60s to lower 70s. The
severe potential does not look overly impressive with this system,
but a few strong storms will not be out of the question. The rain
should move out on Monday morning.
Tuesday through Wednesday look to be dry as high pressure builds
into the area. In the wake of the system Sunday night, temps on
Monday will be back in the 50s. We will then see a warm up through
mid week with temps back into the mid to upper 60s. The next chance
for rain will come Wednesday night into Thursday.
&&
.AVIATION (18Z TAF Update)...
Updated at 115 PM EDT Thu Mar 24 2016
A cold front will push through the terminals during the upcoming
forecast period bringing a few rounds of showers and thunderstorms
to the region. The best chances of thunderstorms will be in the
early part of the TAF period from 24/18Z through 25/01Z.
For this afternoon/evening, we expect VFR to MVFR conditions at the
terminals with scattered showers within the vicinity of the
airports. Some thunderstorms will be possible later this afternoon
and evening and will plan on keeping the VCTS in the ongoing TAF
package. Gradient winds will remain strong with southwest winds of
15-20kts and gusts up over 30kts at times.
For the overnight period (25/03Z and after), cold front is expected
to be clearing the region. Winds will shift from the SW to the W
and remain elevated with speeds of 10-13kts and gusts in the 15-
20kts. These winds should subside overnight and towards dawn on
Friday. Initially ceilings will be near the MVFR/VFR thresholds but
are expected to drop solidly into the MVFR category overnight with
ceilings running from FL015-020.
The outlook for Friday suggests improving conditions throughout the
day. Ceilings will start off at MVFR levels but are expected to rise
to VFR by afternoon with a light northwest wind of 5-7kts.
&&
.LMK Watches/Warnings/Advisories...
KY...Wind Advisory until 7 PM EDT /6 PM CDT/ this evening for
KYZ028>043-045>049-053>057-062>067-071>078-081-082.
IN...Wind Advisory until 7 PM EDT this evening for INZ078-079-091-092.
&&
$$
Update.........KJD
Short Term.....EER
Long Term......EER
Aviation.......MJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
432 PM EDT THU MAR 24 2016
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 432 PM EDT THU MAR 24 2016
AT MID AFTERNOON A COLD FRONT STRETCHED FROM DEEP LOW PRESSURE AT
THE NORTHERN END OF INDIANA TO EXTREME WESTERN KENTUCKY AND ON
SOUTHWESTWARD. SHOWERS WERE OCCURRING AHEAD OF THE FRONT...WITH A
FEW THUNDERSTORMS NEAR THE FRONT. THE LEADING EDGE OF PRECIP WILL
ADVANCE EASTWARD OUT OF KY EARLY THIS EVENING. SOUTH TO SOUTHWEST
WINDS WERE STILL KICKING UP AT TIMES AT MID AFTERNOON...ESPECIALLY
OVER THE WESTERN EDGE OF THE JKL FORECAST AREA. WITH A NPW FOR
WIND ALREADY IN PLACE...WILL LET IT RIDE FOR NOW...WITH STILL
SOME SMALL POTENTIAL TO REACH ADVISORY OR LAKE WIND ADVISORY LATE
TODAY. HOWEVER...IT WOULD APPEAR THAT ASIDE FROM CONVECTION...THE
GREATEST WIND THREAT HAS FADED. ANY THUNDERSTORMS OR HEAVY SHOWERS
ALONG/AHEAD OF THE FRONT HAVE A POTENTIAL TO BRING STRONG
WINDS...AND WE CONTINUE IN A MARGINAL THREAT OF SEVERE STORMS FROM
SPC.
SHOWERS WILL END WITH FROPA...BUT FORECAST SOUNDINGS SHOW A
POTENTIAL FOR SOME DRIZZLE IN LINGERING LOW LEVEL MOISTURE INTO
FRIDAY MORNING. THIS WILL END AND CLOUDS WILL BREAK UP ON FRIDAY
AS SURFACE HIGH PRESSURE PASSES BY TO OUR NORTH. DRIER AIR AND
CLEARING SKIES WILL PRESENT A FROST THREAT IN OUR COLDER VALLEYS
ON FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 302 PM EDT THU MAR 24 2016
EXTENDED PORTION OF THE FORECAST WILL FEATURE PATCHY FROST EARLY
SATURDAY MORNING...MAINLY IN VALLEY LOCATIONS...ABOVE NORMAL
TEMPERATURES FOR MOST OF THE PERIOD...AND TWO PERIODS OF
PRECIPITATION. THE INITIAL BOUT OF RAIN IS ON TRACK FOR SUNDAY
THROUGH MONDAY. BASED ON THE LATEST MODEL DATA...PRECIPITATION
ONSET WILL BE SLOWER THAN PREVIOUSLY FORECAST...WITH THE FIRST
SHOWERS AND STORMS PROGGED TO ENTER OUR SOUTHWESTERN COUNTIES
AROUND 12Z ON SUNDAY. THE RAIN IS EXPECTED TO BE MOST WIDESPREAD
FROM SUNDAY AFTERNOON THROUGH LATE SUNDAY NIGHT...AS A WAVE OF LOW
PRESSURE MOVES OUT OF THE CENTRAL PLAINS...ACROSS THE MID
MISSISSIPPI VALLEY AND THEN ACROSS THE OHIO VALLEY REGION SUNDAY
AND SUNDAY NIGHT. THE LATEST FORECAST MODELS ARE SHOWING JUST
ENOUGH INSTABILITY AND LIFT TO PERHAPS SPARK A FEW THUNDERSTORMS
SUNDAY AFTERNOON AND EVENING. THE CHANCES FOR THUNDER WILL
STEADILY DIMINISH SUNDAY NIGHT AS WE LOSE THE HEATING OF THE DAY
AND THE WEATHER SYSTEM MOVES OFF QUICKLY TO OUR EAST...TAKING ITS
LIFT WITH IT.
WE SHOULD THEN SEE AN EXTENDED BREAK FROM PRECIPITATION FROM
MONDAY NIGHT THROUGH WEDNESDAY...AS A RIDGE OF HIGH PRESSURE
TEMPORARILY SETS UP SHOP ACROSS THE SOUTHERN AND SOUTHEASTERN
CONUS DURING THAT TIME. THE MODELS TRY TO BRING ANOTHER WEATHER
SYSTEM THROUGH THE EASTERN THIRD OF THE CONUS FOR THE MIDDLE OF
THE WEEK. IN GENERAL THE SLOWER ECMWF MODEL WAS USED TO ADJUST THE
MODEL BLEND FORECAST AS WE ARE NOW IN THE WARM SEASON WITH LESS
COLD AIR TO PUSH THIS SYSTEM EASTWARD. THE FORECAST IS CALLING FOR
ISOLATED RAIN SHOWERS TO ENTER EASTERN KENTUCKY FROM THE SOUTHWEST
LATE WEDNESDAY EVENING...WITH ISOLATED TO SCATTERED SHOWERS
OVERSPREADING THE AREA WEDNESDAY NIGHT INTO EARLY THURSDAY
MORNING.
TEMPERATURES ARE EXPECTED TO BE ABOVE NORMAL
SATURDAY...SUNDAY...AND AGAIN ON WEDNESDAY...AS RIDGES OF HIGH
PRESSURE RULE THE WEATHER ON THOSE DAYS. CONDITIONS WILL COOL OFF
QUITE A BIT ON MONDAY AND TUESDAY...AS COOLER AIR SPILLS INTO THE
AREA BEHIND A DEPARTING WEATHER SYSTEM. WE COULD EASILY SEE HIGHS
REACH THE UPPER 60S ON SATURDAY AND WEDNESDAY...AND THE LOW TO MID
70S ON SUNDAY. THE COOLEST DAYS OF THE WEEK LOOK TO MONDAY AND
TUESDAY...WHEN THE MERCURY MAY ONLY TOP OUT IN THE MID TO UPPER
50S FOR MOST LOCATIONS. OVERNIGHT LOWS WILL BE IN THE 30S AND
40S ACROSS THE AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 756 AM EDT THU MAR 24 2016
A LOW LEVEL JET OF 35 TO 40 KTS OUT OF THE SOUTH SOUTHWEST AT
AROUND 2K FEET AGL WILL CONTINUE TO BRING WIND SHEAR CONCERNS TO
THE TAF SITES THROUGH AROUND 14Z. ONCE THE INVERSION MIXES
OUT...STRONG AND GUSTY SOUTH TO SOUTHWEST WINDS WILL ENGAGE.
SUSTAINED SPEEDS WILL RANGE FROM 15 TO 20 KTS...WITH GUSTS IN THE
25 TO 35 KT RANGE. A COLD FRONT WILL MOVE THROUGH THE AREA LATE
THIS AFTERNOON INTO THIS EVENING...BRINGING SHOWERS AND PERHAPS A
FEW THUNDERSTORMS WITH IT. CEILINGS/VISIBILITIES WILL DROP DOWN TO
THE LOW VFR/MVFR RANGE...WITH WINDS SHIFTING FROM THE SOUTHWEST TO
WEST. CEILINGS WILL CONTINUE TO LOWER LATE THIS EVENING BEHIND THE
FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR KYZ044-050>052-
058>060-068-069-079-080-083>085-104-106-108-111-114.
LAKE WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR KYZ086>088-
107-109-110-112-113-115>120.
&&
$$
SHORT TERM...HAL
LONG TERM...AR
AVIATION...GEOGERIAN
[top]
Area Forecast Discussion
National Weather Service Paducah KY
309 PM CDT THU MAR 24 2016
.SHORT TERM...(This evening through Saturday Night)
Issued at 309 PM CDT Thu Mar 24 2016
The band of showers from Owensboro to Madisonville will slowly
push east northeast out of the region by late this afternoon.
We cannot rule out a few lightning strikes, but any significant
intensification should not occur until it passes out of our area.
Recent shower development along the actual cold front near the
Wabash River should struggle to survive as it moves into a worked
over airmass.
The entire area should be dry by 00Z this evening, but low clouds
will overspread the area behind the front, and linger for much of
the night. West northwest winds will slowly weaken through the
night, but they are not expected to go calm by morning. The
combination of clouds and winds should keep temperatures from
dropping down to the freezing mark and frost from forming in the
morning.
Considerable uncertainty exists in how long clouds may linger
Friday, but tried to lean toward the warm side of guidance for
highs. The surface high will still be in control of the region
Friday night, but winds will not be calm. Temperatures should drop
into the 30s over most of the area, but a freeze or frost is
not likely at this time. Plenty of sunshine and a return to south
winds should allow for a nice warm up on Saturday. More
confidently leaned toward the warm side of the guidance envelope
for highs.
An inverted surface trough will develop southwest to northeast
through the region Saturday night, as our Easter storm system
approaches. We should stay dry through sunrise Sunday morning, but
clouds will be on the increase from the west. Guidance is locked
in to the middle 40s for lows so did not deviate much at all.
.LONG TERM...(Sunday through Thursday Night)
Issued at 309 PM CDT Thu Mar 24 2016
In the extended forecast period, the ECMWF guidance is still
preferred from previous forecast shifts given it consistency in
space and time across the WFO PAH forecast area. In addition to the
blended guidance, added a little weighting toward the ECMWF solution
with the first system on Sunday...with confidence greater than 50
percent. Have lower confidence on the early onset of precipitation
with the next system next Wednesday.
The pattern has set up with a progressive mean trough over the
conterminous U.S. through the period, with intervening shortwave
ridges. This would place precipitation event over the area about
every 2-3 days.
With the continual changes from warm to cold advection regimes and
mixing, diurnal ranges will be minimized somewhat, reducing the
concern for late night/early morning freeze potential or record
afternoon highs. Although evapotranspiration is increasing this time
of year, have doubt that there will be large scale drying between
systems.
A compact short wave moves through Sunday and Sunday evening, with
some intensification at the low-middle levels of the atmosphere. At
this point, the best potential for thunderstorms seems to be across
the Delta region of Southeast Missouri and West Kentucky, along and
just east of the forecast surface low moving over the area. Given
the likelihood for outdoor activities Sunday, will continue to
highlight in the Hazardous Weather Outlook.
The system next Wednesday/Thursday is somewhat less distinct, with
periodic shortwaves generating precipitation in a broad southwest
flow regime.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1246 PM CDT Thu Mar 24 2016
Showers should push through KOWB in the next hour or two with MVFR
or even brief IFR conditions. A stray lightning strike cannot be
ruled out. Otherwise winds will veer from south through west
through the afternoon and gust well over 20kts. A large area of
low VFR or MVFR ceilings will overspread the area from mid
afternoon through early evening. Confidence in the duration of the
ceilings is not great. Could see scattering/clearing before
daybreak at KCGI and KPAH, but figure on ceilings lasting through
the end of the period at KEVV and KOWB.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
SHORT TERM...DRS
LONG TERM...Smith
AVIATION...DRS
Area Forecast Discussion
National Weather Service Paducah KY
309 PM CDT THU MAR 24 2016
.SHORT TERM...(This evening through Saturday Night)
Issued at 309 PM CDT Thu Mar 24 2016
The band of showers from Owensboro to Madisonville will slowly
push east northeast out of the region by late this afternoon.
We cannot rule out a few lightning strikes, but any significant
intensification should not occur until it passes out of our area.
Recent shower development along the actual cold front near the
Wabash River should struggle to survive as it moves into a worked
over airmass.
The entire area should be dry by 00Z this evening, but low clouds
will overspread the area behind the front, and linger for much of
the night. West northwest winds will slowly weaken through the
night, but they are not expected to go calm by morning. The
combination of clouds and winds should keep temperatures from
dropping down to the freezing mark and frost from forming in the
morning.
Considerable uncertainty exists in how long clouds may linger
Friday, but tried to lean toward the warm side of guidance for
highs. The surface high will still be in control of the region
Friday night, but winds will not be calm. Temperatures should drop
into the 30s over most of the area, but a freeze or frost is
not likely at this time. Plenty of sunshine and a return to south
winds should allow for a nice warm up on Saturday. More
confidently leaned toward the warm side of the guidance envelope
for highs.
An inverted surface trough will develop southwest to northeast
through the region Saturday night, as our Easter storm system
approaches. We should stay dry through sunrise Sunday morning, but
clouds will be on the increase from the west. Guidance is locked
in to the middle 40s for lows so did not deviate much at all.
.LONG TERM...(Sunday through Thursday Night)
Issued at 309 PM CDT Thu Mar 24 2016
In the extended forecast period, the ECMWF guidance is still
preferred from previous forecast shifts given it consistency in
space and time across the WFO PAH forecast area. In addition to the
blended guidance, added a little weighting toward the ECMWF solution
with the first system on Sunday...with confidence greater than 50
percent. Have lower confidence on the early onset of precipitation
with the next system next Wednesday.
The pattern has set up with a progressive mean trough over the
conterminous U.S. through the period, with intervening shortwave
ridges. This would place precipitation event over the area about
every 2-3 days.
With the continual changes from warm to cold advection regimes and
mixing, diurnal ranges will be minimized somewhat, reducing the
concern for late night/early morning freeze potential or record
afternoon highs. Although evapotranspiration is increasing this time
of year, have doubt that there will be large scale drying between
systems.
A compact short wave moves through Sunday and Sunday evening, with
some intensification at the low-middle levels of the atmosphere. At
this point, the best potential for thunderstorms seems to be across
the Delta region of Southeast Missouri and West Kentucky, along and
just east of the forecast surface low moving over the area. Given
the likelihood for outdoor activities Sunday, will continue to
highlight in the Hazardous Weather Outlook.
The system next Wednesday/Thursday is somewhat less distinct, with
periodic shortwaves generating precipitation in a broad southwest
flow regime.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1246 PM CDT Thu Mar 24 2016
Showers should push through KOWB in the next hour or two with MVFR
or even brief IFR conditions. A stray lightning strike cannot be
ruled out. Otherwise winds will veer from south through west
through the afternoon and gust well over 20kts. A large area of
low VFR or MVFR ceilings will overspread the area from mid
afternoon through early evening. Confidence in the duration of the
ceilings is not great. Could see scattering/clearing before
daybreak at KCGI and KPAH, but figure on ceilings lasting through
the end of the period at KEVV and KOWB.
&&
.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&
$$
SHORT TERM...DRS
LONG TERM...Smith
AVIATION...DRS
Area Forecast Discussion
National Weather Service Louisville KY
305 PM EDT THU MAR 24 2016
.SHORT TERM (Now through Friday Night)...
Issued at 256 PM EDT Thu Mar 24 2016
The concerns this afternoon will continue to be the potential for
severe weather, as well as gradient wind gusts. Gradient winds have
been gusting mainly in the upper 30s to around 40. However, there
have been some gusts as high as 45 mph. The wind advisory continues
until 23Z, but will continue to monitor gusts as it may be able to
be let go before then.
The rain that has moved across central KY today has helped to
stabilize the area. However, SPC mesoanalysis does show an area of
slight instability across west central KY. In addition the 0-6 km
shear values are around 60 knots across the region. Mesoscale models
do suggest that the instability will spread eastward this afternoon
into western portions of the forecast area before weakening towards
the early evening hours. The HRRR continues to show strengthening of
the line of storms right along the cold front into the evening
hours. All things considered, there is still a slight chance for
some strong to severe storms this afternoon with hail and wind
gusts.
The storms should move out of the area by around 03Z or so with some
light showers continuing across the Bluegrass overnight. Rain should
move out completely by daybreak Friday, with dry conditions
expected Friday night.
Temperatures will fall in the wake of the cold front overnight into
the mid 30s to lower 40s. Despite the low temps, frost formation is
not expected as winds will remain elevated overnight. Highs tomorrow
will be much cooler, in the lower to mid 50s. Lows Friday night will
dip into the mid to upper 30s. With light winds and high pressure,
some frost will be possible early Saturday morning.
.LONG TERM (Saturday through Thursday)...
Issued at 305 PM EDT Thu Mar 24 2016
Saturday will remain dry with high pressure ridging in from the
northeast. Temperature will warm into the 60s under mostly sunny
skies. Lows Saturday night will be much warmer, in the 40s areawide.
A trough will dig into the Plains on Sunday and cross the lower Ohio
Valley Sunday night. The best chance for showers and thunderstorms
with this system still looks to be late Sunday afternoon into Sunday
night. Given the dry weather for much of the day ahead of this
system, temperatures will warm into the upper 60s to lower 70s. The
severe potential does not look overly impressive with this system,
but a few strong storms will not be out of the question. The rain
should move out on Monday morning.
Tuesday through Wednesday look to be dry as high pressure builds
into the area. In the wake of the system Sunday night, temps on
Monday will be back in the 50s. We will then see a warm up through
mid week with temps back into the mid to upper 60s. The next chance
for rain will come Wednesday night into Thursday.
&&
.AVIATION (18Z TAF Update)...
Updated at 115 PM EDT Thu Mar 24 2016
A cold front will push through the terminals during the upcoming
forecast period bringing a few rounds of showers and thunderstorms
to the region. The best chances of thunderstorms will be in the
early part of the TAF period from 24/18Z through 25/01Z.
For this afternoon/evening, we expect VFR to MVFR conditions at the
terminals with scattered showers within the vicinity of the
airports. Some thunderstorms will be possible later this afternoon
and evening and will plan on keeping the VCTS in the ongoing TAF
package. Gradient winds will remain strong with southwest winds of
15-20kts and gusts up over 30kts at times.
For the overnight period (25/03Z and after), cold front is expected
to be clearing the region. Winds will shift from the SW to the W
and remain elevated with speeds of 10-13kts and gusts in the 15-
20kts. These winds should subside overnight and towards dawn on
Friday. Initially ceilings will be near the MVFR/VFR thresholds but
are expected to drop solidly into the MVFR category overnight with
ceilings running from FL015-020.
The outlook for Friday suggests improving conditions throughout the
day. Ceilings will start off at MVFR levels but are expected to rise
to VFR by afternoon with a light northwest wind of 5-7kts.
&&
.LMK Watches/Warnings/Advisories...
KY...Wind Advisory until 7 PM EDT /6 PM CDT/ this evening for
KYZ028>043-045>049-053>057-062>067-071>078-081-082.
IN...Wind Advisory until 7 PM EDT this evening for INZ078-079-091-092.
&&
$$
Short Term........EER
Long Term.........EER
Aviation..........MJ
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
325 PM EDT THU MAR 24 2016
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 325 PM EDT THU MAR 24 2016
LOW PRESSURE WILL MOVE EAST OF LOWER MICHIGAN THIS EVENING WITH
RAIN CHANGING TO SNOW AND THEN TAPERING OFF TO SNOW SHOWERS AFTER
MIDNIGHT. HIGH PRESSURE WILL MOVE IN AND PROVIDE FAIR WEATHER FOR
FRIDAY AND SATURDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 325 PM EDT THU MAR 24 2016
WE WILL LET THE WINTER STORM WARNING CONTINUE AS PRECIPITATION
CONTINUES ACROSS THE WARNING AREA WITH TEMPERATURES AROUND
FREEZING. WE DO NOT EXPECT MUCH ADDITIONAL ICING...BUT WINDS
GUSTING TO 30 MPH AND ICE COVERED TREES WILL CONTINUE TO CAUSE
POWER OUTAGES.
ANOTHER THING TO WATCH FOR WILL BE WINDS GUSTING OVER 40 MPH INTO
EARLY EVENING ACROSS THE SOUTHERN TIER AS A LINE OF LOW TOPPED
CONVECTION MOVES THROUGH THERE.
THE SFC LOW WILL TRACK OFF TO THE EAST OF THE FORECAST AREA THIS
EVENING WITH THE HRRR CONSISTENT WITH THE OTHER MODEL GUIDANCE IN
BRINGING A BAND OF DEFORMATION AXIS SNOW ACROSS THE CENTRAL AND
NORTHERN ZONES. THIS COULD PUT DOWN A QUICK COATING OF SNOW ON
THE ROADS AFTER DARK AS TEMPERATURES DROP BLO FREEZING.
ONCE THAT GOES BY...DRYING AND SUBSIDENCE MOVES IN WITH ANY SNOW
SHOWERS ENDING BY 12Z FRIDAY. FAIR AND COOL WEATHER ON FRIDAY INTO
SATURDAY. A WEAK NORTHERN STREAM LOW IS APPROACHING SATURDAY NIGHT
WITH LIGHT RAIN OR MIX ACROSS THE NORTH.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 325 PM EDT THU MAR 24 2016
WE ARE MONITORING TWO SYSTEMS IN THE LONG TERM PORTION OF THE FCST.
ONE IS AT THE BEGINNING OF THE PERIOD ON SUN-MON. THE OTHER IS AT
THE END OF THE PERIOD FOR LATE WED-THU.
THE TREND OVER THE PAST DAY IS FOR DIMINISHING PCPN CHCS FOR THE
SYSTEM FOR SUN-MON. THIS TREND IS THE RESULT OF MORE SEPARATION OF
THE SYSTEMS FROM SAT THROUGH SUN. WE WILL SEE THE FRONT FROM THE SAT
SYSTEM BE FURTHER SOUTH OF THE AREA AS THE WAVE TRIES TO MOVE ALONG
THE FRONT ON SUN-MON. THIS LOOKS TO KEEP PCPN MAINLY SOUTH OF THE
AREA. WE HAVE KEPT RAIN CHCS IN THE FCST INTO MON...BUT HAVE LOWERED
THEM A BIT. SOME SNOW COULD MIX IN ON THE BACKSIDE OF IT AS THERE IS
POTENTIAL OF ENOUGH COOLER AIR MOVING IN BEHIND IT.
THE PERIOD FROM MON NIGHT THROUGH TUE NIGHT LOOKS TO BE DRY WITH
MODERATING TEMPS. WE WILL SEE A NICE AMPLITUDE RIDGE MOVE ACROSS
THE AREA BETWEEN LOWS TO OUR EAST AND WEST.
RAIN CHANCES WILL INCREASE BEGINNING ON WED AND BECOME MORE LIKELY
BY THU. THE STRONG UPPER LOW EXPECTED TO TAKE SHAPE ACROSS THE WRN
U.S. WILL START TO EJECT SHORT WAVES TO THE NE TOWARD THE STATE. THE
INITIAL WAVE EJECTING INTO THE AREA ON WED WILL NOT HAVE A LOT OF
MOISTURE TO WORK WITH. THIS SHOULD CHANGE BY THU AS BETTER MOISTURE
WILL HAVE MOVED FURTHER NORTH AHEAD OF SUBSEQUENT WAVES. WE SHOULD
SEE FAIRLY MILD TEMPS WELL INTO THE 50S AND APPROACHING 60 BEING
OUT AHEAD OF THE MAIN SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 130 PM EDT THU MAR 24 2016
THE MAJORITY OF THE AREA IS SHROUDED BY IFR-LIFR EARLY THIS
AFTERNOON WITH ALL RAIN AT THE TERMINALS. WE EXPECT THESE
CONDITIONS TO HOLD UNTIL ABOUT 21-22Z WHEN A TEMPORARY LULL IN THE
PCPN WILL MOVE IN. CONDITIONS WILL LIKELY HOLD IN THE IFR
CATEGORY...EXCEPT FOR THE I-94 TERMINALS WHICH COULD SNEAK UP TO
MVFR IN THE WARMER PART OF THE SYSTEM. SOME STORMS CURRENTLY IN
ERN ILLINOIS WILL POTENTIALLY AFFECT THE I-94 TERMINALS FOR THE
NEXT 3-4 HRS.
AFTER THE LULL...WE WILL SEE THE TAIL END OF THE SYSTEM MOVE
THROUGH MAINLY KGRR AND KMKG IN THE FORM OF SOME LIGHT RAIN
CHANGING TO LIGHT SNOW. THIS WILL BE POSSIBLE FOR 2-3 HRS BEFORE
IT WOULD MOVE OUT.
CONDITIONS WILL THEN GRADUALLY IMPROVE WITH CIGS COMING UP TO VFR
TOWARD 14Z OR SO ON FRI.
&&
.MARINE...
ISSUED AT 325 PM EDT THU MAR 24 2016
SMALL CRAFT ADVISORY CONTINUES THROUGH FRIDAY MORNING THEN
CONDITIONS WILL BE IMPROVING ON FRIDAY AS HIGH PRESSURE WITH
LIGHTER WINDS MOVES IN.
&&
.HYDROLOGY...
ISSUED AT 325 PM EDT WED MAR 23 2016
WIDESPREAD PRECIPITATION CONTINUED THIS AFTERNOON ACROSS ALL OF
LOWER MICHIGAN. 24 HOUR TOTALS OF AROUND 1 INCH ARE EXPECTED BY 8
AM FRIDAY. RIVER RISES ARE EXPECTED AREA WIDE IN THE KALAMAZOO...
GRAND... AND MUSKEGON RIVER BASINS. NUISANCE FLOODING WILL BE COMMON
OVER THE NEXT WEEK IN LOWLAND AREAS ADJACENT TO RIVER BANKS. MORE
IMPACTFUL MINOR FLOODING ALSO CANNOT BE RULED OUT LATE IN THE
WEEKEND INTO NEXT WEEK.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER STORM WARNING UNTIL 8 PM EDT THIS EVENING FOR MIZ037>040-
043>046-051-052.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EDT FRIDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...NJJ
AVIATION...NJJ
HYDROLOGY...EBW
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 PM EDT THU MAR 24 2016
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL EXTEND ACROSS THE SOUTHEASTERN UNITED
STATES UNTIL A COLD FRONT CROSSES THE REGION ON FRIDAY. THE FRONT
WILL THEN SETTLE SOUTH ACROSS SOUTH CAROLINA AND LINGER THROUGH THE
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 315 PM THURSDAY...
BERMUDA HIGH PRESSURE CONTINUES TO DOMINATE WITH AN UNSEASONABLY
WARM AND SLOWLY MOISTENING AIRMASS OVER THE SOUTHEAST STATES. GUSTY
SOUTH-SOUTHWESTERLY WINDS WILL SUBSIDE THIS EVENING...SETTLING DOWN
TO AROUND 10-12KT AFTER SUNSET AS SLOW MOVING COLD FRONT CRAWLS
THROUGH THE TENN VALLEY AND EVENTUALLY ACROSS THE MOUNTAINS. IT
SEEMS LIKE EVERY MODEL RUN SHOWS A LATER AND LATER ARRIVAL OF THE
FRONT AS ITS PRIMARY UPPER SHORTWAVE SHEARS OFF INTO THE GREAT LAKES
AND THE FRONT RUNS INTO THE PERSISTENT SUB-TROPICAL RIDGE. WITH
ONLY WEAK HEIGHT FALLS AND A RELATIVELY WEAK UPPER JET RIGHT
ENTRANCE REGION....FORCING WILL BE LIMITED TO MAINLY LOW-LEVEL
CONVERGENCE AND THE POSSIBILITY OF AN MCV OR TWO EMANATING FROM GULF
CONVECTION.FORECAST SOUNDINGS DO SHOW SOME WEAK INSTABILITY
DEVELOPING AFTER MIDNIGHT AS THE LOW-LEVELS MOISTEN...THOUGH IT IS
MOSTLY ELEVATED AFTER NOCTURNAL COOLING. THE HRRR SHOWS A
PREFRONTAL BAND OF SHOWERS AND STORMS STRETCHING FROM KENTUCKY TO
ALABAMA THIS AFTERNOON WEAKENING AS IT MOVES INTO WESTERN
NC...LEAVING REALLY JUST A FEW SHOWERS IN THE WESTERN/SOUTHERN
PIEDMONT THROUGH 12Z. BACKED POPS OFF TO JUST HIGH END CHANCE AND
ITS ENTIRELY POSSIBLE THEY ARE STILL TOO HIGH. OVERNIGHT LOWS IN
THE UPPER 50S TO MID 60S LOOK GOOD GIVEN THE STEADY SOUTHERLY WIND
AND INCREASINGLY OVERCAST SKIES.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
AS OF 315 PM THURSDAY...
ONGOING SHOWERS ALONG THE FLOW MOVING FRONT...IF THERE ARE
ANY...SHOULD FIRE BACK UP INTO SOME DEEPER CONVECTION AS THE
COASTAL PLAIN DESTABILIZES (UP TO A 1000 J/KG EAST OF US HWY 1). WHILE
DEEP LAYER WIND FIELDS WILL BE STRONG OVERALL... 40-50KT OF 0-6 KM
BULK SHEAR...THE LOW-LEVEL JET DEPARTING TO THE NORTH AND LACK OF
UPPER FORCING SHOULD LIMIT THE ORGANIZATION OF CONVECTION. A FEW
STRONG STORMS ARE STILL POSSIBLE. WITHOUT MORE WIDESPREAD PRECIP
AND INCREASING BREAKS IN CLOUDS BY MIDDAY...HIGHS SHOULD RANGE FROM
THE LOWER 70S WEST TO UPPER 70S EAST. THE COLD FRONT WILL THEN
FINALLY SURGE ALL THE WAY SOUTH THROUGH THE AREA FRIDAY EVENING AS
HIGH PRESSURE NOSES IN FROM EASTERN CANADA. THE NORTH-NORTHEASTERLY
FLOW WILL BE SHALLOW...WITH SOUTHWESTERLY WINDS ABOVE
3000FT...LEADING TO THE POTENTIAL FROM STRATUS...ESPECIALLY OVER THE
EAST. LOWS 46-53.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 130 PM THURSDAY...
SAT AND SAT NIGHT: A LOW PRESSURE WAVE WILL MOVE NE ALONG THE COLD
FRONT STALLED TO OUR SOUTH...AND WILL SPREAD MOISTURE BACK ACROSS
ERN NC DURING THE DAYTIME. HOWEVER IT APPEARS THAT THE BULK OF
PRECIP SHOULD REMAIN CLOSER TO THE COAST. FARTHER W...THE CAD WEDGE
WILL BE IN PLACE...SO LOOK FOR PARTLY TO MOSTLY CLOUDY SKIES WITH
TEMPS A FEW DEG BELOW NORMAL.
SUN AND SUN NIGHT: LOW PRESSURE WILL MOVE FROM THE NORTHERN GULF
COAST NEWD ACROSS THE CAROLINAS. RAIN CHANCES WILL QUICKLY INCREASE
DURING THE MORNING...WITH THE HEAVIEST RAIN PROGGED ACROSS THE
EASTERN HALF OF THE STATE IN CONJUNCTION WITH THE AFOREMENTIONED
BOUNDARY TO OUR SOUTH LIFTING N AS A WARM FRONT AHEAD OF THE LOW
PRES WAVE. AS ALWAYS THE CASE WHEN LOW PRESSURE MOVES ACROSS THE
CAROLINAS...WE`LL HAVE TO KEEP A CLOSE EYE ON THE POTENTIAL FOR
CONVECTIVE ACTIVITY...BUT IN THIS CASE IT APPEARS THAT THE WARM
SECTOR SHOULD REMAIN MOSTLY EAST OF THE I-95. WITH CLOUDS AND
PRECIP...LOOK FOR LITTLE DIURNAL TEMP CHANGE...SO HIGHS NEAR 70
DURING THE DAY WILL ONLY COOL OFF ABOUT 10 DEG OR SO AT NIGHT.
MON: SHOULD BE TRANSITION DAY AS THE AFOREMENTIONED LOW AND PARENT
UPPER SHORT WAVE TROUGH MOVE ACROSS THE STATE ...FOLLOWED BY
DECREASING CLOUDS LATER IN THE DAY. NOT MUCH OF AN AIRMASS CHANGE
BEHIND THIS SYSTEM...SO LOOK FOR HIGHS ONCE AGAIN NEAR 70.
MON NIGHT THROUGH WED: FAIR WEATHER AND SEASONABLE TEMPS (LOWS
AROUND 40 AND HIGHS IN THE MID-UPR 60S) DURING THIS TIME AS HIGH
PRESSURE BUILDS INTO AND ACROSS THE CAROLINAS.
THUR: WITH THE NEXT COLD FRONT APPROACHING LATE IN THE WEEK...RAIN
CHANCES WILL INCREASE AS THE DAY PROGRESSES.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 130 PM THURSDAY...
VFR CONDITIONS WILL CONTINUE THROUGH 25/06Z...WITH CLOUDS GRADUALLY
THICKENING AND LOWERING AS A COLD FRONT...NOW APPROACHING THE TN
VALLEY...MOVES EAST TOWARD OUR AREA. WINDS THE REST OF THIS
AFTERNOON WILL REMAIN S/SW 10-20KT WITH HIGHER GUSTS IN THE
PREFRONTAL FLOW AHEAD OF THE FRONT. FLT CONDITIONS WILL LOWER TO
MVFR BETWEEN 25/06Z TO 25/10Z AS THE FRONT CLOSES IN ON OUR
AREA...WITH SCATTERED SHOWERS AND LOCALIZED IFR CONDITIONS POSSIBLE
DURING THIS TIME. AFTER 25/12Z...A FEW TSTMS MAY DEVELOP...
PARTICULARLY ACROSS THE COASTAL PLAIN EASTWARD. BY 25/18Z...THE
FRONT SHOULD BE MOVING ACROSS THE I-95 CORRIDOR...WITH THE RISK FOR
PRECIP ENDING QUICKLY IN ITS WAKE.
BEYOND 25/18Z THROUGH THE MIDDLE OF NEXT WEEK: FLT CONDITIONS WILL
BRIEFLY IMPROVE LATE FRIDAY INTO EARLY SUNDAY...BUT WITH THE
AFOREMENTIONED COLD FRONT STALLED JUST TO OUR SOUTH...AND A SERIES
OF LOW PRESSURE WAVES MOVING ALONG IT...SUB-VFR CONDITIONS MAY BE
POSSIBLE AGAIN DURING THE WEEKEND INTO MONDAY. FLT CONDITIONS WILL
THEN IMPROVE TO VFR DURING THE MID-WEEK PERIOD.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...2222
SHORT TERM...22
LONG TERM...RAH
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
314 PM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT CROSSES TONIGHT. LINGERING LOW LEVEL MOISTURE FRIDAY. HIGH
PRESSURE SYSTEM ARRIVES FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
MAIN FOCUS FOR NEAR TERM FORECAST IS COLD FRONT APPROACHING FROM
THE WEST. CLOUDS MAKING IT INTO THE OHIO RIVER VALLEY NOW AS THE
COLD FRONT ENTERS WESTERN KY/IN. HAVE A PRE-FRONTAL BAND OF
PRECIPITATION STRETCHING FROM WESTERN OHIO THROUGH CENTRAL KY.
THIS BAND WILL MOVE THROUGH LATE THIS AFTERNOON AND THIS EVENING.
ONLY WEAK SURFACE CONVERGENCE WITH THIS...AND CAPE IS MEAGER. THE
NAM WHICH OFTEN RUNS HIGH ON CAPE IS STRUGGLING TO BREAK 300J/KG
ACROSS THE WESTERN FORECAST AREA...AND HAS MOST OF THAT BEHIND
THIS FIRST LINE -- CLOSER TO THE COLD FRONT. DID KEEP ISOLATED
THUNDER MENTIONED BUT NOT REAL IMPRESSED WITH POTENTIAL FOR
STRONG/SEVERE CONVECTION THIS FAR EAST. WITH DECENT FLOW IN
PLACE...CANNOT RULE OUT GUSTY OUTFLOW WINDS WITH ANY STRONGER
CELLS. PWATS POOL UP TO AROUND 1.25IN WITH THIS PRE-FRONTAL BAND
AS WELL...SO BRIEF MODERATE TO HEAVY RAIN IS POSSIBLE.
TRIED TO SHOW A BREAK BETWEEN THIS PRE-FRONTAL BAND AND THE
SECONDARY BAND WITH THE COLD FRONT...PWATS SHOWING THIS AS WELL
WITH A QUICK DIP UNDER 1.0IN BEFORE RAMPING BACK UP JUST AHEAD OF
THE FRONT. KEPT ISOLATED THUNDER MENTION GOING UNTIL THIS
SECONDARY BAND PASSES...BUT WITH THIS OCCURRING LATE TONIGHT
TIMING IS NOT IDEAL.
LOW LEVEL MOISTURE GETS TRAPPED IN THE LOW LEVELS...AND LINGERS
THROUGH MOST OF FRIDAY. EXPECT LOW STRATUS AND DRIZZLE THROUGH THE
MORNING...GRADUALLY COMING TO AN END FROM WEST TO EAST DURING THE
AFTERNOON.
TEMPERATURE WISE...HELD TEMPS UP TONIGHT UNTIL THE FRONT
PASSES USING A CONSENSUS BLEND...AND THE HRRR AS FAR OUT AS
POSSIBLE. EXPECT ONLY MINIMAL WARMING TOMORROW.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
A PROGRESSIVE PATTERN THIS PERIOD WITH ZONAL FLOW ALOFT. THE
DOMINATING FEATURE THIS WEEKEND WILL BE HIGH PRESSURE THAT WILL
QUICKLY MOVE EASTWARD ACROSS THE AREA FRIDAY NIGHT AND EARLY
SATURDAY. CLOUDS WILL QUICKLY CLEAR OUR FRIDAY NIGHT AS THE HIGH
PRESSURE WITH DRIER AIR MOVES IN...BUT LOW LEVEL MOISTURE THAT GETS
PUSHED SOUTH FRIDAY NIGHT WILL RETURN DURING SATURDAY ON SOUTHEAST
FLOW AS THE HIGH CENTER SHIFTS OFF THE COAST. THE CLOUDS WILL MAINLY
AFFECT EAST FACING SLOPES OF WEST VIRGINIA AND SOUTHWEST VIRGINIA.
HOWEVER NO PRECIP WITH THIS SHALLOW MOISTURE. REMAINDER OF AREA WILL
SEE ABUNDANT SUNSHINE SATURDAY.
WITH INCREASING SOUTHERLY FLOW AND SUNSHINE SATURDAY...LOOK FOR
TEMPERATURES TO REBOUND INTO THE 60S SATURDAY AFTERNOON. EVEN ON
THE EAST FACING SLOPES...TEMPERATURES WILL WARMER DESPITE THE
CLOUDS. CLOUDS WILL AGAIN SHIFT OUT TO THE SOUTH AND EAST SATURDAY
NIGHT AS LOW LEVEL FLOW BECOMES MORE WESTERLY. THIS WILL ALLOW FOR
A DRY AND MILDER NIGHT SATURDAY NIGHT.
THE FORECAST PROBLEM COMES WITH THE NEXT SYSTEM APPROACHING LATE
SUNDAY. THE MODELS CONTINUE TO BE QUITE DIVERGENT ON THE
STRENGTH...TRACK AND SPEED OF THE SURFACE LOW COMING ACROSS THE
CENTRAL PART OF THE NATION. THE EURO MODEL IS MORE WRAPPED UP AND
MUCH SLOWER WITH THIS SYSTEM WHILE MOST OF THE OTHER MODELS ARE MORE
OPEN AND FASTER. WITH A PROGRESSIVE ZONAL FLOW ALOFT SHOWN BY THE
MODELS...THE LESS AMPLIFIED AND FASTER SOLUTION OF THE MAJORITY OF
THE MODELS WOULD SEEM TO BE THE WAY TO GO. THUS...USING GFS AS A
GUIDE. I HAVE CLOUDS INCREASING DURING THE DAY SUNDAY...AND
SCATTERED SHOWERS ARRIVING WEST OF THE OHIO RIVER BY DAYS END.
STILL...LOOK FOR TEMPERATURES ON SOUTHERLY FLOW TO REACH INTO THE
70S MOST AREAS...ESPECIALLY ACROSS THE EASTERN LOW LANDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ANOTHER COLD FRONT WILL MOVE THROUGH THE AREA SUNDAY NIGHT...WITH
SHOWERS LIKELY AS IT DOES SO. HIGH PRESSURE...WITH COOLER...AND
DRIER AIR BEHIND THE FRONT FOR TUESDAY...WITH A GRADUAL WARMING
TREND TOWARDS MID WEEK AS UPPER RIDGE GRADUALLY BUILDS ACROSS THE
AREA...AS AN UPPER TROUGH DEEPENS ACROSS THE CENTRAL UNITED
STATES. THE TROUGH...AND ASSOCIATED LOW PRESSURE SYSTEM WILL MOVE
INTO THE REGION TOWARDS THE END OF THE EXTENDED
PERIOD...GENERATING ADDITIONAL ROUNDS OF SHOWERS AND
THUNDERSTORMS.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
COLD FRONT APPROACHING FROM THE WEST THIS EVENING...WILL DRIVE
TWO AREAS OF SHOWERS IN FROM THE WEST. THE FIRST LATE THIS
AFTERNOON INTO THIS EVENING WELL AHEAD OF THE FRONT...AND THE
SECOND WITH THE FRONT OVERNIGHT. INSTABILITY IS WEAK...BUT DID
INCLUDE VCTS WITH THE FIRST AREA IN THE TRI-STATE...BUT NO WHERE
ELSE. CANNOT RULE OUT AN ISOLATED RUMBLE HOWEVER...AND WILL NEED
TO MONITOR FOR NEED TO MENTION ELSEWHERE. KEPT THINGS MVFR WITH
THE PRECIP...BUT COULD HAVE BRIEF IFR IN HEAVIER SHOWERS. LOW
LEVEL MOISTURE LINGERS THROUGH MOST OF THE DAY FRIDAY...WITH MVFR
IN LOW STRATUS AND DRIZZLE/FOG.
GUSTY SOUTHERLY WINDS TODAY WILL WEAKEN SOME TONIGHT...BECOMING
WESTERLY AND NOT AS STRONG BEHIND THE FRONT AND INTO FRIDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MAY NEED TO ADD TEMPOS FOR THUNDER AND/OR IFR
DEPENDING ON HOW THINGS PROGRESS.
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 M M M M
HTS CONSISTENCY H H H H H M M M M M M M
BKW CONSISTENCY H H H H H H H H H M M M
EKN CONSISTENCY H H H H H H H H M H M M
PKB CONSISTENCY H H H H H H H M M M M M
CKB CONSISTENCY H H H H H H H M M M M M
AFTER 18Z FRIDAY...
IFR POSSIBLE IN PRECIPITATION SUNDAY NIGHT INTO MONDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/MZ/30
NEAR TERM...MZ
SHORT TERM...JMV
LONG TERM...SL
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
254 PM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT CROSSES TONIGHT. LINGERING LOW LEVEL MOISTURE FRIDAY. HIGH
PRESSURE SYSTEM ARRIVES FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
MAIN FOCUS FOR NEAR TERM FORECAST IS COLD FRONT APPROACHING FROM
THE WEST. CLOUDS MAKING IT INTO THE OHIO RIVER VALLEY NOW AS THE
COLD FRONT ENTERS WESTERN KY/IN. HAVE A PRE-FRONTAL BAND OF
PRECIPITATION STRETCHING FROM WESTERN OHIO THROUGH CENTRAL KY.
THIS BAND WILL MOVE THROUGH LATE THIS AFTERNOON AND THIS EVENING.
ONLY WEAK SURFACE CONVERGENCE WITH THIS...AND CAPE IS MEAGER. THE
NAM WHICH OFTEN RUNS HIGH ON CAPE IS STRUGGLING TO BREAK 300J/KG
ACROSS THE WESTERN FORECAST AREA...AND HAS MOST OF THAT BEHIND
THIS FIRST LINE -- CLOSER TO THE COLD FRONT. DID KEEP ISOLATED
THUNDER MENTIONED BUT NOT REAL IMPRESSED WITH POTENTIAL FOR
STRONG/SEVERE CONVECTION THIS FAR EAST. WITH DECENT FLOW IN
PLACE...CANNOT RULE OUT GUSTY OUTFLOW WINDS WITH ANY STRONGER
CELLS. PWATS POOL UP TO AROUND 1.25IN WITH THIS PRE-FRONTAL BAND
AS WELL...SO BRIEF MODERATE TO HEAVY RAIN IS POSSIBLE.
TRIED TO SHOW A BREAK BETWEEN THIS PRE-FRONTAL BAND AND THE
SECONDARY BAND WITH THE COLD FRONT...PWATS SHOWING THIS AS WELL
WITH A QUICK DIP UNDER 1.0IN BEFORE RAMPING BACK UP JUST AHEAD OF
THE FRONT. KEPT ISOLATED THUNDER MENTION GOING UNTIL THIS
SECONDARY BAND PASSES...BUT WITH THIS OCCURRING LATE TONIGHT
TIMING IS NOT IDEAL.
LOW LEVEL MOISTURE GETS TRAPPED IN THE LOW LEVELS...AND LINGERS
THROUGH MOST OF FRIDAY. EXPECT LOW STRATUS AND DRIZZLE THROUGH THE
MORNING...GRADUALLY COMING TO AN END FROM WEST TO EAST DURING THE
AFTERNOON.
TEMPERATURE WISE...HELD TEMPS UP TONIGHT UNTIL THE FRONT
PASSES USING A CONSENSUS BLEND...AND THE HRRR AS FAR OUT AS
POSSIBLE. EXPECT ONLY MINIMAL WARMING TOMORROW.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
A PROGRESSIVE PATTERN THIS PERIOD WITH ZONAL FLOW ALOFT. THE
DOMINATING FEATURE THIS WEEKEND WILL BE HIGH PRESSURE THAT WILL
QUICKLY MOVE EASTWARD ACROSS THE AREA FRIDAY NIGHT AND EARLY
SATURDAY. CLOUDS WILL QUICKLY CLEAR OUR FRIDAY NIGHT AS THE HIGH
PRESSURE WITH DRIER AIR MOVES IN...BUT LOW LEVEL MOISTURE THAT GETS
PUSHED SOUTH FRIDAY NIGHT WILL RETURN DURING SATURDAY ON SOUTHEAST
FLOW AS THE HIGH CENTER SHIFTS OFF THE COAST. THE CLOUDS WILL MAINLY
AFFECT EAST FACING SLOPES OF WEST VIRGINIA AND SOUTHWEST VIRGINIA.
HOWEVER NO PRECIP WITH THIS SHALLOW MOISTURE. REMAINDER OF AREA WILL
SEE ABUNDANT SUNSHINE SATURDAY.
WITH INCREASING SOUTHERLY FLOW AND SUNSHINE SATURDAY...LOOK FOR
TEMPERATURES TO REBOUND INTO THE 60S SATURDAY AFTERNOON. EVEN ON
THE EAST FACING SLOPES...TEMPERATURES WILL WARMER DESPITE THE
CLOUDS. CLOUDS WILL AGAIN SHIFT OUT TO THE SOUTH AND EAST SATURDAY
NIGHT AS LOW LEVEL FLOW BECOMES MORE WESTERLY. THIS WILL ALLOW FOR
A DRY AND MILDER NIGHT SATURDAY NIGHT.
THE FORECAST PROBLEM COMES WITH THE NEXT SYSTEM APPROACHING LATE
SUNDAY. THE MODELS CONTINUE TO BE QUITE DIVERGENT ON THE
STRENGTH...TRACK AND SPEED OF THE SURFACE LOW COMING ACROSS THE
CENTRAL PART OF THE NATION. THE EURO MODEL IS MORE WRAPPED UP AND
MUCH SLOWER WITH THIS SYSTEM WHILE MOST OF THE OTHER MODELS ARE MORE
OPEN AND FASTER. WITH A PROGRESSIVE ZONAL FLOW ALOFT SHOWN BY THE
MODELS...THE LESS AMPLIFIED AND FASTER SOLUTION OF THE MAJORITY OF
THE MODELS WOULD SEEM TO BE THE WAY TO GO. THUS...USING GFS AS A
GUIDE. I HAVE CLOUDS INCREASING DURING THE DAY SUNDAY...AND
SCATTERED SHOWERS ARRIVING WEST OF THE OHIO RIVER BY DAYS END.
STILL...LOOK FOR TEMPERATURES ON SOUTHERLY FLOW TO REACH INTO THE
70S MOST AREAS...ESPECIALLY ACROSS THE EASTERN LOW LANDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE TO START THE PERIOD WITH A WARM SOUTHWESTERLY FLOW
ACROSS THE AREA...AS UPPER TROUGH DEEPENS ACROSS THE CENTRAL
UNITED STATES. BY LATE SUNDAY INTO MONDAY...A LOW PRESSURE SYSTEM
WILL MOVE INTO THE REGION...SPREADING RAIN...AND ISOLATED
THUNDERSTORMS BACK INTO THE AREA. BEHIND THE SYSTEM...MUCH COOLER
TEMPERATURES FOR TUESDAY...WITH THE POSSIBILITY OF A CHANGE OVER
TO -SHSN ACROSS THE HIGHER TERRAIN MONDAY NIGHT. THE COOLER
WEATHER DOESNT LOOK TO LAST LONG HOWEVER...AS UPPER RIDGING TAKES
HOLD AGAIN BY MID WEEK.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
COLD FRONT APPROACHING FROM THE WEST THIS EVENING...WILL DRIVE
TWO AREAS OF SHOWERS IN FROM THE WEST. THE FIRST LATE THIS
AFTERNOON INTO THIS EVENING WELL AHEAD OF THE FRONT...AND THE
SECOND WITH THE FRONT OVERNIGHT. INSTABILITY IS WEAK...BUT DID
INCLUDE VCTS WITH THE FIRST AREA IN THE TRI-STATE...BUT NO WHERE
ELSE. CANNOT RULE OUT AN ISOLATED RUMBLE HOWEVER...AND WILL NEED
TO MONITOR FOR NEED TO MENTION ELSEWHERE. KEPT THINGS MVFR WITH
THE PRECIP...BUT COULD HAVE BRIEF IFR IN HEAVIER SHOWERS. LOW
LEVEL MOISTURE LINGERS THROUGH MOST OF THE DAY FRIDAY...WITH MVFR
IN LOW STRATUS AND DRIZZLE/FOG.
GUSTY SOUTHERLY WINDS TODAY WILL WEAKEN SOME TONIGHT...BECOMING
WESTERLY AND NOT AS STRONG BEHIND THE FRONT AND INTO FRIDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MAY NEED TO ADD TEMPOS FOR THUNDER AND/OR IFR
DEPENDING ON HOW THINGS PROGRESS.
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 M M M M
HTS CONSISTENCY H H H H H M M M M M M M
BKW CONSISTENCY H H H H H H H H H M M M
EKN CONSISTENCY H H H H H H H H M H M M
PKB CONSISTENCY H H H H H H H M M M M M
CKB CONSISTENCY H H H H H H H M M M M M
AFTER 18Z FRIDAY...
IFR POSSIBLE IN PRECIPITATION SUNDAY NIGHT INTO MONDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/MZ/30
NEAR TERM...MZ
SHORT TERM...JMV
LONG TERM...SL
AVIATION...MZ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
213 PM EDT THU MAR 24 2016
.SYNOPSIS...
A COLD FRONT CROSSES TONIGHT. LINGERING LOW LEVEL MOISTURE FRIDAY. HIGH
PRESSURE SYSTEM ARRIVES FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
MAIN FOCUS FOR NEAR TERM FORECAST IS COLD FRONT APPROACHING FROM
THE WEST. CLOUDS MAKING IT INTO THE OHIO RIVER VALLEY NOW AS THE
COLD FRONT ENTERS WESTERN KY/IN. HAVE A PRE-FRONTAL BAND OF
PRECIPITATION STRETCHING FROM WESTERN OHIO THROUGH CENTRAL KY.
THIS BAND WILL MOVE THROUGH LATE THIS AFTERNOON AND THIS EVENING.
ONLY WEAK SURFACE CONVERGENCE WITH THIS...AND CAPE IS MEAGER. THE
NAM WHICH OFTEN RUNS HIGH ON CAPE IS STRUGGLING TO BREAK 300J/KG
ACROSS THE WESTERN FORECAST AREA...AND HAS MOST OF THAT BEHIND
THIS FIRST LINE -- CLOSER TO THE COLD FRONT. DID KEEP ISOLATED
THUNDER MENTIONED BUT NOT REAL IMPRESSED WITH POTENTIAL FOR
STRONG/SEVERE CONVECTION THIS FAR EAST. WITH DECENT FLOW IN
PLACE...CANNOT RULE OUT GUSTY OUTFLOW WINDS WITH ANY STRONGER
CELLS. PWATS POOL UP TO AROUND 1.25IN WITH THIS PRE-FROTNAL BAND
AS WELL...SO BRIEF MODERATE TO HEAVY RAIN IS POSSIBLE.
TRIED TO SHOW A BREAK BETWEEN THIS PRE-FRONTAL BAND AND THE
SECONDARY BAND WITH THE COLD FRONT...PWATS SHOWING THIS AS WELL
WITH A QUICK DIP UNDER 1.0IN BEFORE RAMPING BACK UP JUST AHEAD OF
THE FRONT. KEPT ISOLATED THUNDER MENTION GOING UNTIL THIS
SECONDARY BAND PASSES...BUT WITH THIS OCCURRING LATE TONIGHT
TIMING IS NOT IDEAL.
LOW LEVEL MOISTURE GETS TRAPPED IN THE LOW LEVELS...AND LINGERS
THROUGH MOST OF FRIDAY. EXPECT LOW STRATUS AND DRIZZLE THROUGH THE
MORNING...GRADUALLY COMING TO AN END FROM WEST TO EAST DURING THE
AFTERNOON.
TEMPERATURE WISE...HELD TEMPS UP TONIGHT UNTIL THE FRONT
PASSES USING A CONSENSUS BLEND...AND THE HRRR AS FAR OUT AS
POSSIBLE. EXPECT ONLY MINIMAL WARMING TOMORROW.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
THE COLD FRONT SHOULD BE EXITING THE MOUNTAINS FIRST THING FRIDAY
MORNING WITH CAA ENSUING. STILL THINKING AN ABUNDANCE OF STRATOCU
WILL THRU THE AFTERNOON HOURS...ESPECIALLY OVER N HALF OF WV. FOR
TEMPS STILL GOING ON THE COOL SIDE OF THE ENVELOPE OVER MOST
AREAS...PARTICULARLY ACROSS N WV. THIS WILL BE A QUICK HITTING
SHOT OF COLD AS WAA ALOFT WILL QUICKLY DEVELOP FRIDAY NIGHT. THIS
WILL ESSENTIALLY SCOUR OUT ANY LINGERING CLOUDS OVER THE N
MOUNTAINS. AS SUCH...A RIDGE/VALLEY SPLIT WAS CODED UP WITH
HILLTOPS AND RIDGES EXPERIENCING A NON DIURNAL TRACE OVERNIGHT.
MOST PLACES SHOULD GET DOWN INTO THE LOWER 30S WITH SOME UPPER 20S
IN THE TYPICAL COLD HOLLOWS. SATURDAY WILL SEE SW FLOW DEVELOP
WITH A CONTINUATION OF WAA. STABLE AIR NEAR THE SURFACE MAY KEEP
HIGHS IN CHECK A BIT BUT STILL ABOVE NORMAL FOR THIS TIME OF
YEAR. ANOTHER RIDGE/VALLEY SPLIT NIGHT SATURDAY NIGHT AMID A
MAINLY CLEAR SKY BUT NOT AS COLD AS PREVIOUS NIGHT. ATTENTION
TURNS TO THE NEXT SYSTEM ON SUNDAY WHICH SHOULD STAY WELL W OF THE
AREA DURING THE DAY. S FLOW WILL STRENGTHEN...RESULTING IN A DAY
IN 70S FOR A GOOD CHUNK OF THE AREA...ALBEIT ON THE WINDY SIDE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE TO START THE PERIOD WITH A WARM SOUTHWESTERLY FLOW
ACROSS THE AREA...AS UPPER TROUGH DEEPENS ACROSS THE CENTRAL
UNITED STATES. BY LATE SUNDAY INTO MONDAY...A LOW PRESSURE SYSTEM
WILL MOVE INTO THE REGION...SPREADING RAIN...AND ISOLATED
THUNDERSTORMS BACK INTO THE AREA. BEHIND THE SYSTEM...MUCH COOLER
TEMPERATURES FOR TUESDAY...WITH THE POSSIBILITY OF A CHANGE OVER
TO -SHSN ACROSS THE HIGHER TERRAIN MONDAY NIGHT. THE COOLER
WEATHER DOESNT LOOK TO LAST LONG HOWEVER...AS UPPER RIDGING TAKES
HOLD AGAIN BY MID WEEK.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
COLD FRONT APPROACHING FROM THE WEST THIS EVENING...WILL DRIVE
TWO AREAS OF SHOWERS IN FROM THE WEST. THE FIRST LATE THIS
AFTERNOON INTO THIS EVENING WELL AHEAD OF THE FRONT...AND THE
SECOND WITH THE FRONT OVERNIGHT. INSTABILITY IS WEAK...BUT DID
INCLUDE VCTS WITH THE FIRST AREA IN THE TRI-STATE...BUT NO WHERE
ELSE. CANNOT RULE OUT AN ISOLATED RUMBLE HOWEVER...AND WILL NEED
TO MONITOR FOR NEED TO MENTION ELSEWHERE. KEPT THINGS MVFR WITH
THE PRECIP...BUT COULD HAVE BRIEF IFR IN HEAVIER SHOWERS. LOW
LEVEL MOISTURE LINGERS THROUGH MOST OF THE DAY FRIDAY...WITH MVFR
IN LOW STRATUS AND DRIZZLE/FOG.
GUSTY SOUTHERLY WINDS TODAY WILL WEAKEN SOME TONIGHT...BECOMING
WESTERLY AND NOT AS STRONG BEHIND THE FRONT AND INTO FRIDAY.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MAY NEED TO ADD TEMPOS FOR THUNDER AND/OR IFR
DEPENDING ON HOW THINGS PROGRESS.
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 M M M M
HTS CONSISTENCY H H H H H M M M M M M M
BKW CONSISTENCY H H H H H H H H H M M M
EKN CONSISTENCY H H H H H H H H M H M M
PKB CONSISTENCY H H H H H H H M M M M M
CKB CONSISTENCY H H H H H H H M M M M M
AFTER 18Z FRIDAY...
IFR POSSIBLE IN PRECIPITATION SUNDAY NIGHT INTO MONDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...MZ/30
NEAR TERM...MZ
SHORT TERM...30
LONG TERM...SL
AVIATION...MZ