Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 03/18/14
AREA FORECAST DISCUSSION...UPDATED
NWS LITTLE ROCK AR
1223 AM CDT SUN MAR 16 2014
.DISCUSSION...
UPDATED TO INCLUDE THE 06Z AVIATION DISCUSSION BELOW...
&&
.AVIATION...
WIDESPREAD SHRA AND SOME TSRA ONGOING ACROSS THE STATE
TONIGHT...AND WILL CONTINUE FOR MOST SITES INTO THE DAYLIGHT HRS.
MVFR TO LIFR CONDITIONS COULD BE SEEN. THE POTENTIAL FOR PRECIP
DECREASES SIGNIFICANTLY AFTER DAWN AT CENTRAL AND ESPECIALLY FOR
THE SRN SITES...BUT FOG AND LOW CIGS WILL CONTINUE. PRECIP WILL
CONTINUE ACROSS THE NORTH INTO THE AFTERNOON HRS. BREEZY NW AND
NORTH WINDS WILL BE SEEN AS WELL...WITH SOME SITES SEEING GUSTS
OVER 30 KTS. RAIN WILL SWITCH TO SNOW ACROSS THE NRN SITES FOR SUN
AFTERNOON...WITH SOME ACCUMULATIONS POSSIBLE. FURTHER SOUTH...THE
TRANSITION WILL OCCUR LATE IN THE AFTERNOON INTO THE EVENING
HRS...BUT ONLY LIGHT AMOUNTS WILL BE POSSIBLE. IMPROVING
CONDITIONS AREA WIDE WILL LIKELY OCCUR AFTER THIS TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 902 PM CDT SAT MAR 15 2014/
UPDATE...
NO APPRECIABLE CHANGES ARE NEEDED THIS EVENING AS FORECAST LOOKS
IN REASONABLY GOOD SHAPE. LOW TEMPERATURES WERE LOWERED BY A
DEGREE HERE AND THERE TO REFLECT CURRENT TRENDS. ALSO...POPS WERE
RAISED TO ONE HUNDRED PERCENT AS RAIN HAS OVERSPREAD JUST ABOUT
THE ENTIRE CWA. REMAINDER OF THE FORECAST WILL BE LEFT IN TACT.
LOW CENTER VISIBLE ON MOISTURE CHANNEL IMAGERY OVER THE TEXAS HILL
COUNTRY AT THIS TIME. QUICK PEEK AT THE NEW MODELS SHOW THE LOW
LIFTING TO THE NORTHEAST THROUGH THE NIGHT...INTENSIFYING AS IT
DOES. NEW NAM SOLUTION KEEPS THE RAIN GOING THROUGH MID MORNING
WHILE OLD GFS/LATEST HRRR DRY SLOTS CENTRAL AND SOUTHERN SECTIONS
A LITTLE QUICKER. STATUS QUO SEEMS TO BE PRUDENT UNTIL NEW MODEL
DATA ARRIVES.
PREV DISCUSSION... /ISSUED 337 PM CDT SAT MAR 15 2014/
SHORT TERM...TONIGHT THROUGH MONDAY
SYNOPTIC OVERVIEW: HIGH AMPLITUDE RIDGING OVER THE CALIFORNIA COAST
WILL ALLOW FOR TWO SHORT WAVE TROUGHS TO DIVE DEEP ACROSS THE
SOUTHERN PLAINS TODAY. 1ST WAVE IS USHERING A BROAD SWATH OF PACIFIC
MOISTURE AHEAD OF IT WITH STRONG SOUTHERLY WINDS ALOFT. A SURFACE
LOW WILL FORM IN RESPONSE ACROSS TX...WITH A NEARLY STATIONARY FRONT
ACROSS THE AREA SLOWLY LIFTING NORTH AS A WARM FRONT. THE FRONT
WILL SET UP ACROSS NORTH CENTRAL AR...WITH GULF MOISTURE SPREADING
NORTHWARD. SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS AFTERNOON
ACROSS THE SW AR...AND OVERSPREAD THE REGION TONIGHT AS THE UPPER
LEVEL SYSTEM PUSHES INTO WESTERN AR.
MEANWHILE...THE SECOND UPPER LEVEL SYSTEM WILL DEEPEN...DIVING SOUTH
ACROSS NORTHERN MEXICO AND SOUTHERN TX. THIS DEEPER SYSTEM WILL
INGEST THE FIRST WAVE AS THE AXES BECOME ALIGNED...AND
BROAD...POSITIVELY TILTED TROUGH DEVELOPS. MOISTURE WILL CONTINUE TO
GET WRAPPED AROUND THE SYSTEM ALOFT...KEEPING PRECIP CHANCES GOING
THROUGH THE OVERNIGHT HOURS. IT APPEARS THAT A DRY SLOT WILL FORM BY
SUNDAY MORNING AS DRIER AIR WORKS IN ON THE NORTHWEST SIDE OF THE
LOW. PRECIP CHANCES WILL LESSEN ACROSS CENTRAL AND SOUTHERN AR.
THE COLD AIR WILL PUSH IN FROM THE NORTH EARLY ON SUNDAY AS A COLD
FRONT MOVES IN TO NORTHERN ARKANSAS AS IT SWEEPS SOUTH THROUGH THE
STATE. TEMPERATURES WILL GENERALLY FALL THROUGH THE AFTERNOON
ACROSS NORTH AND CENTRAL AR. THE SYSTEM WILL PULL AWAY FROM THE
STATE OVERNIGHT ON SUNDAY AND EARLY ON MONDAY MORNING...WITH
PRECIP COMING TO AN END.
HEAVY RAIN: GIVEN THE TWO MOISTURE SOURCES...FROM THE GULF OF MEXICO
AND PACIFIC...HEAVY RAINFALL OF 2 TO 3 INCHES WILL OCCUR ACROSS THE
HIGHER TERRAIN OF THE NORTHWEST. THE FIRST WAVE WILL MOVE ACROSS
NORTHWEST AR TONIGHT...AND WITH STRONG ASCENT AND TRAINING...THESE
HIGHER AMOUNTS WILL BE LIKELY. LESSER AMOUNTS OF 1 TO 2 WILL BE
NOTED FURTHER SOUTH. SOME FLASH FLOODING WILL BE POSSIBLE IN THE
HIGHER TERRAIN...HOWEVER...GIVEN THE RAINFALL DEFICIT OF
LATE...EXPECT PROBLEMS TO REMAIN ISOLATED.
THUNDERSTORMS: GIVEN THE AMPLE ENERGY WITH THESE WAVES THUNDERSTORMS
WILL DEVELOP...ALTHOUGH WILL NOT BE AS WIDESPREAD AS THE SHOWERS.
CONVECTION WILL LIKELY BE MORE ELEVATED ACROSS THE MUCH OF THE
STATE...WITH THE BEST CHANCE FOR ANYTHING SURFACE BASED ACROSS THE
FAR SOUTH AND WEST THIS EVENING. AS THE SURFACE LOW STRENGTHENS
AND MOVES EAST OVERNIGHT...THE HIGHEST DEW POINTS AND BEST DYNAMICS/WIND
SHEAR WILL BE OVER THE FAR SOUTHEAST. HOWEVER...GIVEN THAT THIS IS
OCCURRING OVERNIGHT...INSTABILITY WILL BE LACKING REDUCING THE
SEVERE THREAT.
WINTER WEATHER: COLD AIR WILL GET WRAPPED INTO THE STORM SYSTEM
ALOFT AS A COLD FRONT PUSHES IN ARKANSAS FROM THE NORTH. A
CHANGE OVER FROM RAIN...TO A RAIN/SNOW MIX...TO SNOW WILL OCCUR A
BIT EARLIER THAN PREVIOUSLY EXPECTED. THE WINTER WEATHER WILL LIKELY
BEGIN IN IN THE AFTERNOON...WITH UP TO AROUND 2 INCHES OF
ACCUMULATION POSSIBLE WITH LOCALLY HIGHER AMOUNTS APPROACHING 3
INCHES. AGAIN THIS WILL BE ACROSS THE FAR NORTHERN/NORTHWEST
COUNTIES. SNOW WILL MIX IN ACROSS CENTRAL AREAS LATER ON
SUNDAY...WITH NO ACCUMULATION EXPECTED.
HIGH WINDS...STRONG LOW LEVEL JETS WILL DEVELOP ON THE BACKSIDE OF
THE LOW PRESSURE SYSTEM ON SUNDAY. SUSTAIN WINDS OF 20 TO 30
MPH...WITH HIGHER GUSTS TO 45 MPH WILL BE POSSIBLE. A WIND
ADVISORY WILL BE IN EFFECT FOR MOST OF SUNDAY.
LONG TERM...TUESDAY THROUGH SATURDAY
DOES NOT LOOK LIKE MUCH WILL HAPPEN IN THE EXTENDED PERIOD. THERE
WILL BE A COUPLE OF FRONTS...BUT ASSOCIATED STORM SYSTEMS WILL GO
WELL TO THE NORTH WITH NOT MUCH ENERGY TO HELP TRIGGER
PRECIPITATION. MOISTURE WILL TEND TO BE LIMITED ANYWAY.
THE FIRST FRONT WILL ARRIVE LATE TUESDAY...BUT SHOULD GO THROUGH
DRY. THE LATTER FRONT WILL PUSH INTO THE REGION FRIDAY NIGHT.
MOISTURE LOOKS A LITTLE BETTER...SO ADDED SMALL CHANCES FOR SHOWERS
AT THIS POINT.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 24 46 34 65 / 50 10 0 10
CAMDEN AR 31 54 38 72 / 30 10 0 10
HARRISON AR 18 47 36 63 / 30 10 0 10
HOT SPRINGS AR 29 53 38 69 / 40 10 0 10
LITTLE ROCK AR 29 52 37 69 / 40 10 0 10
MONTICELLO AR 31 51 37 69 / 30 10 0 10
MOUNT IDA AR 28 54 37 69 / 30 10 0 10
MOUNTAIN HOME AR 20 46 35 64 / 40 10 0 10
NEWPORT AR 25 45 34 65 / 50 10 0 10
PINE BLUFF AR 30 50 37 69 / 40 10 0 10
RUSSELLVILLE AR 26 53 35 68 / 40 10 0 10
SEARCY AR 27 48 34 66 / 50 10 0 10
STUTTGART AR 29 49 37 68 / 50 10 0 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 7 AM THIS MORNING TO 10 PM CDT THIS EVENING
FOR ARKANSAS-BAXTER-BOONE-BRADLEY-CALHOUN-CLARK-CLEBURNE-
CLEVELAND-CONWAY-DALLAS-DESHA-DREW-FAULKNER-FULTON-GARLAND-GRANT-
HOT SPRING-INDEPENDENCE-IZARD-JACKSON-JEFFERSON-JOHNSON-LINCOLN-
LOGAN-LONOKE-MARION-MONROE-MONTGOMERY-NEWTON-OUACHITA-PERRY-PIKE-
POLK-POPE-PRAIRIE-PULASKI-SALINE-SCOTT-SEARCY-SHARP-STONE-VAN
BUREN-WHITE-WOODRUFF-YELL.
&&
$$
AVIATION...62
AREA FORECAST DISCUSSION
NWS NEW YORK NY
802 PM EDT MON MAR 17 2014
.SYNOPSIS...
HIGH PRESSURE BUILDS IN FROM THE NORTH THROUGH TUESDAY...WHILE
DEEPENING LOW PRESSURE PASSES WELL TO THE SOUTH AND EAST. LOW
PRESSURE WILL THEN TRACK NORTHEAST ACROSS THE GREAT LAKES WEDNESDAY
AND INTO EASTERN CANADA WEDNESDAY NIGHT...SENDING A COLD FRONT
ACROSS THE REGION. HIGH PRESSURE RETURNS FOR THE END OF THE WEEK
BEFORE ANOTHER FRONTAL SYSTEM IMPACTS THE AREA ON SATURDAY. HIGH
PRESSURE BUILDS IN FOR SUNDAY AND MONDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
HIGH PRESSURE ACROSS EASTERN CANADA WILL CONTINUE TO STRENGTHEN
AND BUILD SOUTH THROUGH THE NIGHT AS HEIGHTS BUILD ALOFT. THIS
WILL RESULT IN A NE FLOW TONIGHT...WHICH GRADUALLY STRENGTHENS
LATE TONIGHT AS THE GRADIENT TIGHTENS BETWEEN THE HIGH AND
DEEPENING LOW PRESSURE OF THE SE COAST.
MAIN FORECAST CHALLENGE FOR OVERNIGHT IS WHEN HIGH BASED STRATO-
CU WILL ERODE. RAP MODEL GUIDANCE HAS SOME IDEA OF ITS
EXISTENCE...BUT IT IS TOO QUICK WITH ITS EROSION OVER THE NEXT
COUPLE OF HOURS BASED ON UPSTREAM DEVELOPMENT. HAVE SLOWED DOWN
EROSION FROM W TO E THROUGH MIDNIGHT...WITH CLEARING SKIES
LATE...WITH WORSE CASE IT MAY TAKE UNTIL WEAK SHORTWAVE ENERGY
SLIDES EAST TUE MORNING.
THIS WILL MAKE FOR TRICKY TEMPS FORECAST...AS TEMPS WILL NOT BEGIN
FALLING OFF MUCH UNTIL CLOUD SCOUR. FOR NOW HAVE SLOWED COOLING
TREND THROUGH MIDNIGHT...THEN DROPPING THEN QUICKLY ACROSS
OUTLYING AREAS LATE TONIGHT WITH RADIATIONAL COOLING. THIS WILL
HAVE TO BE ADJUSTED WITH CLOUD COVER TRENDS. TEMPS WILL RUN
SEVERAL DEGREES BELOW NORMAL.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE CONTINUES TO BUILD IN FROM THE NORTH ON TUE...WHILE
A DEEPENING LOW PASSES WELL SOUTH AND EAST OF THE REGION. THIS
WILL KEEP THE AREA DRY AND UNSEASONABLY COLD. HIGHS WILL TOP OUT
AROUND 40...WHICH IS STILL ABOUT 10 DEGREES BELOW NORMAL.
NE WINDS WILL VEER AROUND TO THE EAST TUE NIGHT. MODEL TIME
HEIGHT CROSS SECTIONS SHOW AN INCREASE IN LOW-LEVEL MOISTURE BY
DAYBREAK WED...BUT WILL HOLD OFF ON ANY CLOUDS AT THIS TIME AS
THIS IS A REAL DRY AIR MASS.
LOWS TUE NIGHT WILL REMAIN BELOW FREEZING WITH MOST LOCATIONS IN
THE 20S.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
A SURFACE LOW MOVES NORTH OF THE REGION WEDNESDAY NIGHT WITH THE
ASSOCIATED COLD FRONT SLIDING ACROSS THE AREA. LIGHT SNOW SHOWERS
WILL BE POSSIBLE ACROSS AREAS WEST OF NEW YORK CITY EARLY WEDNESDAY.
SHOWERS WILL BECOME LIKELY WEDNESDAY AFTERNOON INTO WEDNESDAY
EVENING. MAX TEMPERATURES ON WEDNESDAY WILL BE IN THE MID TO UPPER
40S. WITH NIGHT TIME LOWS IN THE LOWER 30S INLAND AND MID TO UPPER
30S ALONG THE COAST.
COLD FRONT PUSHES OFFSHORE THURSDAY...AS SOUTHERN HIGH PRESSURE
BUILDS BRIEFLY ACROSS THE AREA THURSDAY AND THURSDAY NIGHT.
TEMPERATURES ON THURSDAY AND FRIDAY WILL BE SLIGHTLY WARMER THAN
WEDNESDAY WITH MAX IN THE UPPER 40S TO LOWER 50S.
ANOTHER MID LEVEL TROUGH FROM THE NORTHERN PLAINS SHOULD PUSH A COLD
FRONT THROUGH THE AREA SATURDAY. THE FRONT IS ANTICIPATED TO BRING
ANOTHER ROUND OF RAIN SHOWERS TO OUR AREA. MAX TEMPERATURES ON
SATURDAY WILL BE IN THE UPPER 40S TO LOWER 50S WITH NIGHTTIME
TEMPERATURES IN THE MID 20S INLAND AND UPPER 20S TO LOWER 30S ALONG
THE COAST. A POLAR HIGH PRESSURE WILL BUILD ACROSS THE AREA SUNDAY
INTO MONDAY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
VFR AS HIGH PRESSURE BUILDS OVER QUEBEC. BKN/OVC MID AND HIGH
LEVEL CLOUDS WILL MOVE OUT THIS EVENING.
NE SFC FLOW PERSISTS...BECMG ELY ON TUE.
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)
KEWR FCSTER COMMENTS: GUSTS UP TO 20 KT POSSIBLE 12Z - 16Z TUE.
KJFK FCSTER COMMENTS: GUSTS UP TO 20 KT POSSIBLE 12Z - 16Z TUE.
KLGA FCSTER COMMENTS: GUSTS UP TO 20 KT POSSIBLE 12Z - 16Z TUE.
KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
KISP FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.
.OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
.TUE NGT...VFR.
.WED-WED NGT...IFR DEVELOPING TOWARDS EVENING. -RA OVERNIGHT. SE
WIND G20-25KT DURING THE DAY.
.THU...VFR. W WIND G20-25KT.
.FRI...VFR.
.SAT...MVFR. -RA.
&&
.MARINE...
A PERSISTENT E/NE FLOW THROUGH MID WEEK WILL KEEP SEAS ON THE OCEAN
WATERS RIGHT AROUND 4 TO 6 FT. WINDS WILL BE MARGINAL FOR SCA
WITH POSSIBLE GUSTS UP TO 25 KT ON TUE. SMALL CRAFT CONDITIONS ARE
LIKELY TO REMAIN ON THE WATERS FOR SEVERAL DAYS.
SMALL CRAFT ADVISORY CONDITIONS ARE LIKELY ON THE OCEAN WATERS ON
WEDNESDAY AS A COLD FRONT APPROACHES FROM THE WEST WEDNESDAY
NIGHT. SMALL CRAFT ADVISORY CONDITIONS SHOULD PERSIST THROUGH
FRIDAY. SMALL CRAFT CONDITIONS ON THE OCEAN SUBSIDE LATE FRIDAY
INTO FRIDAY NIGHT. SCA CONDITIONS MAY BE MET AGAIN ON SATURDAY
WITH SOUTHERLY WINDS ASSOCIATED WITH ANOTHER COLD FRONT.
&&
.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH THE WEEK.
&&
.EQUIPMENT...
THE NOAA WEATHER RADIO TRANSMITTER THAT SERVES THE NEW YORK CITY
METROPOLITAN AREA REMAINS OUT OF SERVICE DUE TO RADIO FREQUENCY
INTERFERENCE WITH THE U.S COAST GUARD TRANSMITTER.
FOR MORE INFORMATION SEE THE FOLLOWING PUBLIC INFORMATION
STATEMENT (ALL LOWER CASE):
WWW.ERH.NOAA.GOV/OKX/PRODUCTS/STATIC.TXT
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...FIG/DW
NEAR TERM...DW/NV
SHORT TERM...DW
LONG TERM...FIG
AVIATION...
MARINE...FIG/DW
HYDROLOGY...FIG/DW
EQUIPMENT...
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
934 PM EDT MON MAR 17 2014
.UPDATE...
AN UPPER LEVEL TROUGH OF LOW PRESSURE WAS LOCATED OVER THE EASTERN
GULF OF MEXICO THIS EVENING...AS A COLD FRONT WAS SLOWLY MOVING
THROUGH SOUTH CENTRAL FLORIDA. THE UPPER LEVEL TROUGH WILL
CONTINUE TO MOVE EAST THROUGH THE FLORIDA PENINSULA THROUGH THE
OVERNIGHT HOURS PUSHING THE COLD FRONT THROUGH SOUTH FLORIDA. THIS
WILL ALLOW FOR SHOWERS AND EVEN SOME THUNDERSTORM TO DEVELOP OVER
SOUTH FLORIDA THROUGH THE OVERNIGHT HOURS.
THE LATEST SHORT RANGE MODELS CONTINUE TO SHOW A LOW TO MID LEVEL
JET OF 50 KNOTS TO MOVE EAST FROM THE GULF OF MEXICO INTO SOUTH
FLORIDA THROUGH THE OVERNIGHT HOURS. THIS LOW TO MID LEVEL JET
COULD HELP TO PRODUCE SOME STRONG TO EVEN SEVERE THUNDERSTORMS OVER
SOUTH FLORIDA THROUGH THE OVERNIGHT HOURS. THE STORM PREDICTION
CENTER IS ALSO STILL SHOWING A SLIGHT RISK OF SEVERE FOR THE
OVERNIGHT HOURS.
SO WILL CONTINUE TO SHOW LIKELY POPS OVER THE AREA FOR THE
OVERNIGHT HOURS...AND TO CONTINUE TO MENTION SOME STRONG TO SEVERE
STORMS IN THE HWO PACKAGE FOR SOUTH FLORIDA.
REST OF THE FORECAST LOOKS GOOD AT THIS TIME AND NO OTHER CHANGES
ARE PLANNED.
&&
.AVIATION...
THE WINDS WILL BE IN A SOUTH TO SOUTHEAST DIRECTION THIS EVENING
AROUND 10 KNOTS BEFORE SWINGING TO A SOUTHWEST TO WEST DIRECTION
AND INCREASING TO 15 TO 20 KNOTS BY LATE TONIGHT INTO EARLY
TUESDAY MORNING AT ALL OF THE TAF SITES. THE WINDS WILL THEN
BECOME NORTHWEST TUESDAY MORNING INTO TUESDAY AFTERNOON...BUT
DECREASE TO AROUND 10 TO 15 KNOTS BY TUESDAY AFTERNOON.
VCSH WILL REMAIN IN THE ALL OF SOUTH FLORIDA TAF SITES THIS
EVENING BEFORE ADDING VCTS TO ALL OF THE TAF SITES AFTER 07Z. THE
VCTS WILL REMAIN IN THE TAF SITES UNTIL 12/13Z TUESDAY...THEN VCSH
UNTIL 14/15Z TUESDAY.
AT THIS TIME THE CEILING AND VIS WILL REMAIN IN VFR CONDITIONS DUE
TO THE UNKNOWN TIMING OF THE SHOWERS AND THUNDERSTORMS.
&&
.UPDATE...54/BNB
.AVIATION...54/BNB
.PREV DISCUSSION... /ISSUED 605 PM EDT MON MAR 17 2014/
UPDATE...
THE LINE OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THE COLD
FRONT WAS LOCATED FROM CENTRAL FLORIDA SOUTHWEST INTO THE
SOUTHEAST GULF OF MEXICO. THIS LINE OF SHOWERS AND THUNDERSTORMS
HAS SLOWLY WEAKENED THROUGH LATE THIS AFTERNOON. THE LINE OF
SHOWERS AND THUNDERSTORMS SHOULD CONTINUE TO MOVE SLOWLY SOUTH
INTO THE LAKE OKEECHOBEE REGION LATE THIS EVENING...BEFORE
CONTINUING TO MOVE THROUGH SOUTH FLORIDA THROUGH THE EARLY MORNING
HOURS OF TUESDAY. SO WILL LOWER THE POPS OVER SOUTH FLORIDA THIS
EVENING...BUT KEEP THE LIKELY POPS IN PLACE FOR THE LATE NIGHT
HOURS TONIGHT OVER SOUTH FLORIDA.
THE LATEST SHORT RANGE MODELS CONTINUE TO SHOW THE MID TO UPPER
LEVEL TROUGH OF LOW PRESSURE OVER THE EASTERN GULF OF MEXICO TO
MOVE OVER THE FLORIDA PENINSULA TONIGHT BRINGING A LOW TO MID
LEVEL OF 50 KNOTS THROUGH SOUTH FLORIDA. THIS JET COULD HELP
REGENERATE THE LINE OF SHOWERS AND THUNDERSTORMS OVER SOUTH
FLORIDA AND BRING A SLIGHT RISK OF STRONG TO EVEN SEVERE STORMS TO
THE AREA. SO WILL CONTINUE TO MENTION THIS IN THE HWO PACKAGE AT
THIS TIME.
&&
UPDATE...54/BNB
PREV DISCUSSION... /ISSUED 334 PM EDT MON MAR 17 2014/
DISCUSSION...
AN INTERESTING EVENING/NIGHT IS AHEAD OF US. A POSITIVELY TILTED
UPPER LEVEL TROUGH IS LOCATED ACROSS THE MS VALLEY. A SURFACE LOW
ACROSS SOUTHEASTERN US WILL CONTINUE MOVING EAST...WITH ITS
ASSOCIATED FRONTAL BOUNDARY BEGINNING TO MOVE APPROACH OUR AREA
THIS EVENING. THESE FEATURES WERE WELL DEPICTED BY ALL GUIDANCE
THIS MORNING. STRONG STORMS...A FEW MAY BY SEVERE...ARE STILL
POSSIBLE MAINLY ACROSS THE LAKE OKEECHOBEE AREA AND SOUTHWEST
FLORIDA COAST BEGINNING THIS EVENING. BOTH THE GFS AND ECMWF SHOW
THE MAIN SOURCE OF ENERGY REMAINING ACROSS NORTH/CENTRAL
FLORIDA...THEREFORE EXPECT THE MOST INTENSE ACTIVITY TO REMAIN
NORTH FROM OUR AREA. DESPITE THAT...THESE MODELS ALSO SHOW A LOW
LEVEL JET ACROSS OUR AREA AND UPPER LEVEL JET WITH ASSOCIATED
DIVERGENCE ALOFT...THEREFORE DAMAGING STRAIGHT- LINE WINDS COULD
BE GENERATED WITH ANY STORM THAT DEVELOPS.
CONVERSELY...THE LATEST HRRR AND OTHER HIGH RES MODEL RUNS
DEPICT A LESS ACTIVE LINE MOVING ACROSS SOUTH FLORIDA
TONIGHT...PARTICULARLY AFTER TRAVERSING THE MAINLAND TOWARD
SOUTHEAST FLORIDA OVERNIGHT. BUT AFTER ANALYZING ALL THE
OBSERVATIONS AND MODELS AVAILABLE AT THIS POINT...STILL CANT RULE
OUT THE POSSIBILITY OF STRONG STORMS OVERNIGHT.
DRIER AIR WILL SPREAD ACROSS OUR AREA TUESDAY THROUGH THE MID-
WEEK PERIOD IN THE WAKE OF THE FRONT AS HIGH PRESSURE BUILDS
EASTWARD. TEMPERATURES WILL REMAIN AROUND NORMAL THROUGH THE
PERIOD. ANOTHER WEAK BOUNDARY WILL APPROACH THE PENINSULA SOMETIME
THURSDAY THROUGH FRIDAY WITH HIGH PRESSURE QUICKLY BUILDING IN
BEHIND IT ACROSS THE REGION FOR THE UPCOMING WEEKEND. RAIN CHANCES
WILL REMAIN LOW FOR NOW FOR THE LATTER PART OF THE WEEK INTO NEXT
WEEKEND WITH TEMPERATURES ABOVE NORMAL.
AVIATION...
THERE HAS BEEN A DELAY IN THE ANTICIPATED POTENTIAL FOR CONVECTION
THIS AFTERNOON. HOWEVER...THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS CONTINUES. CURRENTLY THERE IS A LINE OF SHOWERS AND
THUNDERSTORMS IN THE EASTERN GULF THAT COULD POTENTIALLY REACH
TERMINAL KAPF AROUND 00Z. FOR THIS AFTERNOON...THE OCCURRENCE FOR
SHOWERS/THUNDERSTORMS COULD HAPPEN AT ANY TIME BUT IN TAF`S
ASSIGNED ALL TERMINALS VCTS AT 20Z AND CONTINUING AT 00Z. THE
GREATEST COVERAGE OF SHOWERS/THUNDERSTORMS IS EXPECTED AFTER 00Z.
WITH THAT IN MIND AND CONSIDERING THE UNCERTAINTY...MOST OF THE
TAF`S END AT 00Z WITH VCTS. THERE IS A CHANCE OF SEVERE
WEATHER...WITH DAMAGING WINDS BEING THE GREATEST THREAT ALTHOUGH
AN ISOLATED TORNADO IS POSSIBLE. SO FAR THE TIMING OF ANY
POTENTIAL SEVERE WEATHER IS MAINLY EXPECTED IN THE LATE EVENING
AND OVER NIGHT.
MARINE...
A COLD FRONT WILL APPROACH AND MOVE THROUGH THE MARINE
AREA THROUGH TONIGHT. MODERATE TO FRESH SOUTH SOUTHWEST WINDS
ALONG WITH INCREASING RAIN CHANCES WILL BE ANTICIPATED THROUGH
TUESDAY MORNING AS THIS BOUNDARY MOVES THROUGH. WINDS AND SEAS
WILL QUICKLY TREND DOWN THROUGH THE MID WEEK PERIOD AS HIGH
PRESSURE BUILDS EAST ACROSS THE REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 74 81 68 82 / 70 30 0 10
FORT LAUDERDALE 76 81 69 82 / 70 30 10 10
MIAMI 75 82 69 83 / 70 40 10 10
NAPLES 70 79 61 84 / 60 20 0 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...23/SK
LONG TERM....54/BNB
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
1251 PM EDT SUN MAR 16 2014
.UPDATE...INTENSE SQUALL LINE OVER FL PNDL INTO SW GA MOVING QUICKLY
EASTWARD. WHILE IT WILL BE MOVING INTO A PROGRESSIVELY LESS UNSTABLE
ENVIRONMENT OVER TIME...CANNOT DISCOUNT LATEST HRRR SUGGESTING BOWING
CONVECTIVE SEGMENT THAT MOVES INTO OUR WESTERN COUNTIES 18-21Z BEFORE
WEAKENING SUBSTANTIALLY THEREAFTER. HAVE INCREASED THUNDERSTORM
PROBABILITIES IN OUR HOURLY FORECASTS FOR OUR WESTERN COUNTIES.
THERE WILL BE POTENTIAL FOR STRONG GUSTY WINDS IF THE LINE CAN HOLD
TOGETHER AS IT MOVES INTO OUR WESTERNMOST COUNTIES OVER THE NEXT
2-3 HRS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 74 61 65 52 / 80 90 90 80
SSI 77 63 63 53 / 40 90 90 90
JAX 81 64 69 58 / 20 90 90 90
SGJ 78 68 68 59 / 10 80 90 90
GNV 81 64 71 57 / 20 90 90 90
OCF 83 66 75 59 / 10 80 90 80
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...LAKE WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR ALACHUA-BAKER-
BRADFORD-CLAY-COLUMBIA-DUVAL-FLAGLER-GILCHRIST-HAMILTON-
MARION-NASSAU-PUTNAM-ST JOHNS-SUWANNEE-UNION.
GA...NONE.
AM...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO NOON EDT MONDAY
FOR ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20 NM TO 60 NM
OFFSHORE-FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM
OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM
OFFSHORE.
&&
$$
WOLF/ALLEN
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
442 AM EDT SUN MAR 16 2014
.DISCUSSION...
...BREEZY/WINDY CONDITIONS TODAY...INCREASING RAIN CHANCES TONIGHT...
...RISK OF STRONG/SEVERE STORMS MONDAY AFTERNOON AND MONDAY NIGHT...
TODAY...
A HI AMP MID/UPR LVL SHORT WAVE TROF SPANNING THE PLAINS STATES WILL
ALLOW A STORM SYSTEM NEAR THE ARKLATEX TO DEEPEN...WHILE A ZONAL
H30-H20 JET E OF THE MS RIVER VALLEY PULLS THE SYSTEM STEADILY EWD.
AS IT DOES...IT WILL INTERACT WITH A HI PRES RIDGE DRAPED OVER THE
WRN ATLC/ERN GOMEX AND TIGHTEN THE LCL PGRAD. GEOSTROPHIC APPROX
TABLES SUGGEST SUSTAINED WINDS 15-20KTS WITH GUSTS ARND 25KTS. LAKE
WIND ADVISORIES WILL BE IN EFFECT FOR ALL COUNTIES BTWN 10AM AND 8PM.
THE FRESHENING SRLY FLOW WILL RESULT IN STRONG WARM AIR ADVECTION
THAT WILL PUSH MAX TEMPS INTO THE L/M80S...ABOUT 5F ABV AVG. LOW LVL
MOISTURE WILL INCREASE AS WELL AS LATEST RUC ANALYSIS INDICATES
H100-H85 MEAN RH VALUES BTWN 70-80PCT. HOWEVER...UPSTREAM H85-H70
LAPSE RATES RUNNING BLO 4.0C/KM SUGGEST THE MID LVL SUBSIDENCE
INVERSION WILL NOT BREAK THRU THE MAX HEATING PD. EVENING SOUNDINGS
MEASURED PWAT VALUES APPROACHING 1.0" ACRS THE PENINSULA...BUT
SUBSTANTIAL DRY AIR LINGERS ABV H85. AIRMASS REMAINS TOO DRY/STABLE
TO SUPPORT PRECIP TODAY...FCST WILL REMAIN DRY THRU SUNSET.
TONIGHT...
THE ATLC HI PRES RIDGE WILL RETREAT EWD AS THE STORM SYSTEM PUSHES
ACRS THE DEEP SOUTH...BUT WILL NOT GIVE GROUND EASILY. THE SHORT
WAVE TROF SUPPORTING THE STORM SYSTEM HAS A POSITIVE TILT WHILE THE
H30-H20 WIND FIELD BEHIND IT IS MAXING OUT ARND 80KTS. WITHOUT A
STRONGER DIGGING JET...THE SUPPORTING SHORT WAVE WILL NOT BE ABLE
UNDERGO THE POSITIVE-TO-NEGATIVE SHIFT THAT WOULD ALLOW THE STORM
SYSTEM TO INTENSIFY ENOUGH TO COLLAPSE THE WRN FLANK OF THE ATLC
RIDGE AND ALLOW A RAPID FROPA THRU CENTRAL FL.
A PRE FRONTAL CONVECTIVE BAND DRIVEN BY STRONG UPR LVL DIVERGENCE
OVER A STRENGTHENING H85 WIND FIELD SHOULD APPROACH THE I-4 CORRIDOR
AFT MIDNIGHT AND PUSH S OF THE CORRIDOR BY EARLY MORNING. WILL
MAINTAIN 40-50 POPS FROM N BREVARD/NW OSCEOLA NORTHWARD. PRECIP BAND
WILL BE FAIRLY TIGHT...BUT WILL INTRODUCE SMALL POPS TO COUNTIES
FROM OKEECHOBEE/S BREVARD SWD...WHICH IS ROUGHLY CONSISTENT WITH MAV
MOS GUIDANCE. STEADY SRLY WINDS AND INCREASING CLOUD COVER WILL KEEP
MIN TEMPS 10-15F ABV AVG...M/U60S OVER MOST OF THE CWA EXCEPT NEAR
70F ALONG THE IMMEDIATE SPACE AND TREASURE COASTS.
MON/MON NIGHT...A POTENT POSITIVELY TILTED UPPER TROUGH WILL PUSH
EAST ACROSS THE GULF OF MEXICO WHICH WILL INDUCE A SFC LOW TO
DEVELOP IN THE EASTERN GULF. STRONG SW FLOW IN THE MID AND UPPER
LEVELS WILL OVERLAY AN INCREASING 925-850 MB FLOW OF 40-45 KNOTS
IN RESPONSE TO SFC LOW DEVELOPMENT. THIS WILL PULL VERY HIGH
PRECIPITABLE WATER VALUES (AROUND 2 INCHES) ACROSS THE FL
PENINSULA.
TEMPS ALOFT ARE PROGGED TO WARM SLIGHTLY TO -10C AT 500 MB WHICH
IS STILL SUPPORTIVE OF STRONG UPDRAFTS. IN THE LOW LEVELS...A WARM
MOIST AIRMASS WILL BE IN PLACE RESULTING IN SOME AIRMASS
DESTABILIZATION...WITH MAX TEMPS REACHING THE LOW TO MID 80S AND
DEWPOINTS IN THE MID TO UPPER 60S. BUT THERE WILL BE PROBABLY BE
QUITE A BIT OF CLOUDINESS INHIBITING SFC HEATING.
BASED ON CURRENT TIMING...EXPECT A PRE FRONTAL TROUGH TO PUSH
ONSHORE THE FL WEST COAST FROM THE GULF OF MEXICO DURING THE DAY
ACCOMPANIED BY A SQUALL LINE. THIS LINE SHOULD PUSH INTO EAST
CENTRAL FL DURING THE LATE AFTN AND EVENING HOURS CAPABLE OF
PRODUCING DAMAGING WIND GUSTS AND PERHAPS A TORNADO. WE COULD SEE
DEVELOPMENT OF STORMS AHEAD OF MAIN CONVECTIVE BAND DURING THE
EARLY AFTERNOON WHICH TYPICALLY ARE MORE LIKELY TO PRODUCE
TORNADOES. THERE ARE SOME INDICATIONS THAT THE CONVECTIVE BAND
WILL ONLY SLOW TRAVERSE THE AREA MON NIGHT. THIS COULD LEAD TO
SOME TRAINING OF CELLS AND LOCALLY HEAVY RAIN AMOUNTS. AT THIS
TIME...WIDESPREAD ONE HALF /0.50/ TO TO ONE /1.0/ INCH RAINS CAN
BE EXPECTED ACROSS MUCH OF EC FL WHICH WOULD BE QUITE BENEFICIAL.
BUT SOME AREAS WILL LIKELY GET TOO MUCH OF A GOOD THING...UP TO 3
INCHES WHICH COULD CAUSE LOCALIZED TEMPORARY FLOODING.
TUE-SAT...00Z GFS AND ECMWF CONTINUE TO TREND A LITTLE SLOWER WITH
COLD FRONTAL PASSAGE...NOW EXPECTED EARLY TUESDAY. THERE WILL
LIKELY BE ONGOING SHOWERS AND STORMS TUE MORNING SO HAVE RAISED
POPS TO 40-50 PERCENT BUT EXPECT THE RAIN TO PUSH QUICKLY OFFSHORE
IN THE AFTERNOON AS LOW PRESSURE PUSHES SEAWARD AND MUCH DRIER AIR
MOVES IN ALOFT. HOWEVER...SKIES DONT LOOK TO CLEAR OUT COMPLETELY
DUE TO QUICK RETURN OF ONSHORE FLOW WHICH TRAPS SOME LOW LEVEL
MOISTURE.
THE REMAINDER OF THE WEEK LOOKS TRANQUIL WITH HIGH PRESSURE
PUSHING EAST ACROSS THE DEEP SOUTH THEN OFFSHORE THE CAROLINA
COAST FRIDAY. THIS WILL PRODUCE A LIGHT NORTHEAST TO EAST FLOW
AND SLIGHTLY ABOVE NORMAL TEMPERATURES IN THE LOWER 80S COAST AND
MID 80S INLAND. THE BAND OF MOISTURE ASSOCD WITH THE FRONT IS
FORECAST TO STAY TO OUR SOUTH SO RAIN CHANCES LOOK QUITE LOW.
&&
.AVIATION...
THRU 17/04Z...VFR ALL SITES. AFT 16/14Z...S/SE SFC WND G23-28KTS ALL
SITES CONTG THRU 17/00Z...CIGS AOA FL120 N OF KISM-KTIX. BTWN
17/04Z-17/06Z...MVFR CIGS DVLPG N OF KISM-KTIX WITH SLGT CHC SHRAS.
&&
.MARINE...
TODAY-TONIGHT...STORM SYSTEM DVLPG OVER THE ARKLATEX/WRN GOMEX WILL
INTERACT WITH A HI PRES RIDGE EXTENDING FM THE W ATLC TO THE ERN
GOMEX. THE LCL PGRAD WILL TIGHTEN AS THE TWO SYSTEMS INTERACT...
ALLOWING SFC/BNDRY LYR WINDS TO FRESHEN OUT OF THE S/SE...BCMG A
FRESH TO STRONG BREEZE BY MID AFTN. WINDS EXPECTED TO REACH THE 20KT
SCA THRESHOLD OVER MOST OF THE LCL ATLC BY MIDDAY...CONTG THRU
DAYBREAK MON WHILE SLOWLY VEERING TO S/SW OVERNIGHT.
THE SE-SW WIND FIELD WILL PREVENT SEAS FROM BUILDING MUCH ABV 7FT
DUE TO THE LIMITED FETCH LENGTHS FROM BOTH FLOW REGIMES (S/SE WINDS
WILL HAVE THE BAHAMA SHADOW...S/SW WINDS WILL BE OFFSHORE).
HOWEVER...THE LIMITED FETCH LENGTH ALSO MEANS THE SEAS WILL BE
COMPRISED MAINLY OF LCL WIND WAVES WITH DOMINANT PDS AOB 6SEC. THE
S/SE WINDS ALSO WILL GENERATE ROUGH CONDITIONS OVER THE INTRACOASTAL
WATERWAY TODAY AS THEY WILL BE BLOWING ROUGHLY PARALLEL TO THE E FL
COAST.
WILL HOIST AN SCA FOR ALL WATERS BEGINNING AT 14Z...CONTG THRU EARLY
MON MORNING. LAKE WIND ADVISORIES WILL BE ISSUED FOR ALL COUNTIES AS
WELL.
MON...SURFACE LOW PRESSURE OVER THE DEEP SOUTH AND GULF OF MEXICO
SHOULD GENERATE BREEZY SOUTH SOUTHWEST WINDS...WITH SPEEDS AROUND
20 KNOTS OFFSHORE. IN ADDITION THERE WILL BE A CHANCE FOR STRONG
STORMS MOVING OFFSHORE ESPECIALLY IN THE AFTERNOON AND INTO THE
NIGHTTIME.
TUE-THU...THE COLD FRONT AND THE ASSOCIATED BAND OF SHOWERS/STORMS
SHOULD LINGER OVER THE WATERS TUE MORNING. SOUTH/SOUTHWEST WINDS
AHEAD OF THE FRONT MAY STILL BE 20 KNOTS THEN A NORTH SURGE
BEHIND THE FRONT SHOULD ALSO OCCUR. BY WED THE FRONT IS PROGGED TO
BE SOUTHEAST OF THE WATERS WITH WEAK HIGH PRESSURE PROVIDING NORTH
NORTHEAST WINDS 10 KNOTS OR LESS. REINFORCING HIGH PRESSURE IS
FORECAST TO BUILD TO THE CAROLINA COAST THU AND BUMP UP NORTHEAST
FLOW TO AROUND 15 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 82 68 79 66 / 10 50 80 80
MCO 85 66 83 67 / 10 50 80 80
MLB 82 70 84 69 / 0 30 60 70
VRB 81 70 85 73 / 0 20 50 70
LEE 83 67 80 65 / 10 50 80 80
SFB 84 67 82 67 / 10 50 80 80
ORL 84 67 82 67 / 10 50 80 80
FPR 81 71 85 73 / 0 20 50 70
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...LAKE WIND ADVISORY FOR ALL OF EAST CENTRAL FLORIDA 10 AM EDT
TO 8 PM EDT.
AM...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT
MONDAY FOR COASTAL WATERS FROM FLAGLER BEACH TO JUPITER INLET
OUT 20 NM.
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 10 AM EDT MONDAY
FOR WATERS FROM FLAGLER BEACH TO JUPITER INLET 20 TO 60 NM
OFFSHORE.
&&
$$
SHORT TERM...BRAGAW
LONG TERM....KELLY
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
136 AM EDT SUN MAR 16 2014
.PREV DISCUSSION... /ISSUED 1025 PM EDT SAT MAR 15 2014/
UPDATE...
FORECAST LOOKS ON TRACK THIS EVENING WITH REGIONAL RADAR BEGINNING
TO BECOME ACTIVE OVER CENTRAL ALABAMA WITH A BAND OF RAPIDLY
DEVELOPING LIGHT RAIN IN ISENTROPIC ASCENT ZONE. AREA IS ALSO
LIKELY BEING AIDED BY APPROACHING SHORTWAVE OVER THE LOWER
MISSISSIPPI VALLEY WHICH IS ACTING TO CREATE A ZONE OF UPPER LEVEL
DIFFLUENCE OVER THE LOCAL AREA. MODELS ALL IN GOOD AGREEMENT IN
THIS AREA EXPANDING QUICKLY NORTH AND EAST THROUGH THE OVERNIGHT
PERIOD WITH CATEGORICAL POPS OVER NORTH GEORGIA BY 12Z SUNDAY. IN
VICINITY OF WARM FRONT DURING THIS TIME...LOW LEVEL WIND SHEAR
WILL BECOME MAXIMIZED WITH HELICITY VALUES AT 0-1KM IN THE 400-500
M2/S2 RANGE. INSTABILITY HOWEVER...EVEN MUCAPE VALUES...ARE
FORECAST TO BE NEARLY NON EXISTENT WITH BETTER SURFACE BASED
INSTABILITY LAGGING FAR BEHIND THIS INITIAL SHEAR. STILL COULD SEE
SOME GOOD ELEVATED THUNDERSTORM COVERAGE GIVEN STRONG ISENTROPIC FLOW
DURING THIS TIMEFRAME.
MODELS CONTINUE TO PUSH BACK TIMING OF BEST INSTABILITY TO THE
AFTERNOON HOURS. EVEN THEN...INSTABILITY WEAKENS SIGNIFICANTLY
COMPARED TO AREAS TO THE WEST AS WEDGE BUILDS IN. AREAS ALONG AND
SOUTH OF A CSG TO MCN LINE COULD STILL SEE SOME SURFACE BASED
ACTIVITY PER LATEST HRRR AND WRF WHICH SHOWS BOWING CONVECTIVE
ELEMENTS OVER THE SOUTHERN TIER.
DEESE
PREV DISCUSSION... /ISSUED 804 PM EDT SAT MAR 15 2014/
PREV DISCUSSION... /ISSUED 332 PM EDT SAT MAR 15 2014/
SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
FORECAST AREA REMAINS UNDER INCREASING SOUTHWESTERLY UPPER FLOW
THROUGH THE PERIOD AS THE UPPER TROUGH AXIS REMAINS WEST OF THE
STATE. WEDGE FRONT BACKS INTO THE REGION TONIGHT AND HOLDS ITS
GROUND THROUGH SUNDAY EVENING AGAINST THE APPROACHING SURFACE LOW
ASSOCIATED WITH THE UPPER SYSTEM. PRECIPITATION SPREADS OVER NORTH
AND CENTRAL GEORGIA TONIGHT INTO EARLY SUNDAY. INSTABILITY INCREASES
EARLY SUNDAY AND THUNDER IS POSSIBLE ACROSS MOST OF THE AREA BY
MIDDAY. I HAVE INCLUDED A SLIGHT CHANCE FOR THUNDER A LITTLE FURTHER
NORTH AND EAST OVER THE WEDGE AS SOME ELEVATED CONVECTION SHOULD
MAKE IT ONTO THE COOL SIDE OF THE FRONT. CHANCES FOR SEVERE
THUNDERSTORMS ARE LIMITED AS THE BEST INSTABILITY AND LOW/MID-LEVEL
SHEAR REMAIN A BIT OUT OF SYNC AND MUCH OF THE NORTHERN AND EASTERN
PORTIONS ARE DOMINATED IN THE LOWEST LEVELS BY THE WEDGE...BUT
CANNOT BE DISMISSED ENTIRELY AS AMPLE DEEPER LAYER SHEAR REMAINS
PRESENT THROUGH MUCH OF THE DAY DUE TO STRONGER UPPER-LEVEL WINDS.
BETTER PRECIPITATION BEGINS PUSHING EAST OF THE AREA OVERNIGHT
SUNDAY INTO EARLY MONDAY...BUT WITH THE UPPER TROUGH AXIS STILL WEST
OF THE STATE POPS REMAIN RELATIVELY HIGH.
QPF TOTALS THROUGH MONDAY COME OUT AROUND AN INCH AND A HALF...AND
ALTHOUGH ISOLATED MINOR FLOODING IS A POSSIBILITY...NO WIDESPREAD
HYDROLOGICAL ISSUES ARE EXPECTED AT THIS TIME.
20
LONG TERM /MONDAY THROUGH SATURDAY/...
GUIDANCE AGREES WITH SHORTWAVE ENERGY AND OVERRUNNING MOISTURE
STILL ADVECTING NEWD ON MONDAY INTO TUESDAY. DISCREPANCIES EXIST
IN THE STRENGTH OF THE CAD WEDGE AND THE PROGRESSION OF THE
TROUGH/MOISTURE. 12Z NAM IS COOLER/STRONGER WEDGE BUT WARMER BLEND
OF GUIDANCE LOOKS MOST REASONABLE WITH MONDAY NIGHT LOWS IN UPPER
30S TO LOW 40S. HAVE OVERALL TRENDED TEMPS DOWN A BIT FROM
PREVIOUS FORECAST PER LATEST BLEND THROUGH TUESDAY. HAVE ALSO
ADJUSTED POPS ALONG WITH PROGGED SLUG OF ISENTROPIC UPGLIDE
LINGERING INTO TUESDAY FOR PORTIONS OF THE EAST. THIS LESS
PROGRESSIVE SOLUTION IS CARRIED BY THE NAM AND 12Z ECMWF AND SEEMS
MORE LIKELY THAN THE QUICKER GFS. OTHERWISE HAVE LEFT REST OF
FORECAST PERIOD ALONE WITH MINOR ADJUSTMENTS DUE TO UNCERTAINTY
WITH GUIDANCE VARIATION. PREVIOUS DISCUSSION FOLLOWS...
BAKER
PREV DISCUSSION... /ISSUED 357 AM EDT SAT MAR 15 2014/
LONG TERM /MONDAY THROUGH FRIDAY/...
ECMWF AND GFS ARE IN FAIRLY GOOD AGREEMENT WITH BOTH SHOWING AN
UPPER DISTURBANCE PUSHING A WEAK SURFACE LOW ACROSS PARTS OF
CENTRAL AND SOUTH GEORGIA MONDAY AND MONDAY NIGHT. THE DRIVING
UPPER DISTURBANCE DOES NOT PUSH EAST OF THE AREA UNTIL TUESDAY...
SO WRAP AROUND MOISTURE AND PATCHES OF LIGHT RAIN MAY LINGER ON
TUESDAY. AS THE SURFACE LOW APPROACHES ON MONDAY... MODELS SHOW A
COOL WEDGE OF HIGH PRESSURE NOSING DOWN FROM THE NORTHEAST AND
PROVIDING A STABLE AIR MASS OVER THE AREA MONDAY AND MONDAY NIGHT.
THIS SUGGEST THE GREATER THUNDERSTORM THREAT WILL BE ACROSS SOUTH
GEORGIA AND FLORIDA MONDAY-TUESDAY AS THE LOW PRESSURE SYSTEM
MOVES ACROSS. HOWEVER... IF THE WARM FRONT IS ABLE TO ADVANCE INTO
PARTS OF CENTRAL GEORGIA MONDAY AFTERNOON... ISOLATED
THUNDERSTORMS MAY HAVE TO BE ADDED WITH LATER FORECAST.
OTHERWISE... LONG RANGE MODELS SHOW A WEAK COLD FRONT POSSIBLY
BRINGING A LOW CHANCE OF RAIN TO THE AREA BY MID WEEK... WITH THE
GFS THE FASTEST AND SHOWING A FROPA ON WEDNESDAY... WHILE THE
ECMWF SHOWS WEDNESDAY NIGHT-THURSDAY. BOTH ARE FAIRLY DRY WITH
THIS SYSTEM... SO WILL ONLY SHOW A SLIGHT CHANCE OF SHOWERS ACROSS
NORTH GA WEDNESDAY AND WEDNESDAY NIGHT FOR NOW. MODELS SHOW DRY
HIGH PRESSURE SETTLING OVER THE DEEP SOUTH FOR THURSDAY AND
FRIDAY.
39
&&
.AVIATION...
06Z UPDATE...
LOW VFR CIGS TO START THE PERIOD WITH -SHRA BEGINNING TO MOVE
ACROSS THE AREA. EXPECT CIGS TO DROP TO MVFR BY 09Z AND IFR BY 15Z
EXCEPT MCN AND CSG. CSG LOOKS TO STAY MAINLY MVFR THROUGH THE
PERIOD BUT MCN SHOULD DROP TO IFR AFTER 00Z. WIDESPREAD SHRA
THROUGH THE DAY WITH MVFR TO OCCASIONALLY IFR VSBY. POSSIBILITY
OF TSRA THIS AFTERNOON 18-00Z ESPECIALLY CSG AND MCN...CONFIDENCE
NOT AS HIGH FOR METRO TAFS. ALL INDICATIONS ARE FOR LIFR CIGS TO
DEVELOP OVERNIGHT SUNDAY NIGHT. WINDS MAINLY ON THE E SIDE FOR
NORTHERN TAFS BUT FOR CSG/MCN EXPECT WINDS TO SHIFT TO SW AROUND
NOON.
//ATL CONFIDENCE...06Z UPDATE...
HIGH ON OCCURRENCE OF MOST EVENTS...MEDIUM ON TIMING.
TDP
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 56 45 48 38 / 100 80 70 60
ATLANTA 60 47 51 38 / 100 70 60 40
BLAIRSVILLE 52 44 49 38 / 100 70 50 40
CARTERSVILLE 60 48 53 39 / 100 60 60 30
COLUMBUS 66 56 63 45 / 90 70 70 40
GAINESVILLE 54 43 46 37 / 100 70 60 40
MACON 66 54 58 44 / 90 80 70 60
ROME 61 49 54 40 / 100 60 50 30
PEACHTREE CITY 63 49 53 41 / 100 70 70 40
VIDALIA 72 58 59 45 / 80 80 90 60
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ATWELL
LONG TERM....ATWELL
AVIATION...TDP
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
228 PM CDT SUN MAR 16 2014
.DISCUSSION...
1025 AM CDT
FOR MORNING UPDATE...
MADE SOME CHANGES TO FORECAST TODAY MAINLY FOR LAKE EFFECT
FLURRIES/LIGHT SNOW SHOWERS OVER PARTS OF FAR NORTH/NORTHEAST IL...
AND TWEAKS TO MAINTAIN SOME MENTION OF WEAKENING LIGHT SNOW/FLURRIES
ACROSS THE FAR SOUTH INTO EARLY THIS AFTERNOON.
15Z SURFACE ANALYSIS DEPICTS HIGH PRESSURE OVER THE NORTHERN GREAT
LAKES...WHILE FARTHER SOUTH AN AREA OF LOW PRESSURE WAS OVER THE
LOWER MISSISSIPPI VALLEY. THIS LOW WAS ASSOCIATED WITH A FAIRLY DEEP
SHORT WAVE TROUGH NOTED OVER THAT REGION IN MORNING GOES WATER VAPOR
IMAGERY. THE PRECIPITATION SHIELD FROM THE LOW PRESSURE SYSTEM
EXTENDED ACROSS MUCH OF SOUTHERN MISSOURI INTO PARTS OF CENTRAL AND
SOUTHERN IL/INDIANA...THOUGH A NARROW WEAKENING BAND OF LIGHT SNOW
HAD PERSISTED EVEN FARTHER NORTH ROUGHLY ALONG A LINE ROUGHLY FROM
QUINCY-MACOMB-MORRIS. THIS BAND OF SNOW HAD PRODUCED HIGHER
REFLECTIVITY RADAR RETURNS JUST OFF TO THE SOUTHWEST OF THE CWA...
THOUGH HAS WEAKENED STEADILY OVER THE PAST FEW HOURS. STILL...HAVE
INDICATED SOME LOWER CHANCE POPS FOR LIGHT SNOW/FLURRIES ACROSS THE
FAR SOUTH CWA INTO EARLY AFTERNOON AS THIS BAND CONTINUES TO
DISSIPATE AND DRIFT SOUTHEAST.
ACROSS FAR NORTHERN IL...COLD LOW LEVEL NORTHEAST FLOW OFF LAKE
MICHIGAN WAS PRODUCING AND AREA OF LAKE-INDUCED FLURRIES AND SNOW
SHOWERS...PARTICULARLY ACROSS SE WI AND IL COUNTIES ADJACENT TO THE
STATE LINE. FORECAST SOUNDINGS MAINTAIN NORTHEAST WIND FIELD THROUGH
THE DAY...GRADUALLY WEAKENING AND VEERING MORE EAST IN THE LOW
LEVELS TOWARD EVENING. THIS WOULD SUGGEST MAINTAINING A THREAT OF
SOME LIGHT SNOW SHOWERS ACROSS THESE SAME AREAS. HOWEVER...ADVECTION
OF DRY LOW LEVEL AIR APPEARS TO BE RESULTING IN A DECREASE IN DEPTH
OF LAKE-EFFECT STRATOCU PER GOES VISIBLE LOOP...AND HIGH-RES
GUIDANCE INCLUDING OUR LOCAL 8 KM ARW INDICATE DECREASING RH IN THE
CLOUD BEARING LAYER THROUGH THIS AFTERNOON. THUS HAVE INDICATED
DECREASING POPS FOR SNOW SHOWERS LATE THIS MORNING...DIMINISHING TO
SCATTERED FLURRIES ACROSS FAR NORTH/NORTHEAST IL INTO THIS
AFTERNOON.
OTHER THAN SOME ACCOMPANYING TWEAKS TO SKY COVER COINCIDENT WITH
POP/WX ADJUSTMENTS...REMAINDER OF FORECAST APPEARS IN GOOD SHAPE AT
THIS TIME AND NO OTHER CHANGES MADE THROUGH THIS EVENING.
RATZER
//PREV DISCUSSION...
322 AM CDT
THE MAIN FORECAST CONCERNS CENTER MAINLY AROUND TEMPERATURES THROUGH
THE PERIOD...WITH A TYPICAL SPRING SEE SAW PATTERN OF WARMER PERIODS
FOLLOWED BY COOLER PERIODS THROUGH THE UPCOMING WEEK.
A DECENT AREA OF SNOW HAS DEVELOPED ACROSS IOWA AND NORTHERN
ILLINOIS OVERNIGHT. THIS BAND OF SNOW IS ASSOCIATED WITH A STRONG
BAND OF FRONTOGENESIS THAT EXISTS WITHIN THE FAVORABLE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET STREAK ACROSS THE GREAT LAKES. RADAR
RETURNS SUGGEST THAT THIS BAND OF SNOW IS FAIRLY INTENSE ACROSS
PORTIONS OF THE I-80 CORRIDOR AS OF THIS WRITING. VISIBILITIES UNDER
THIS BAND OF SNOW RANGE FROM AROUND 1 TO 2 MILES. HOWEVER...SOME OF
THE MORE INTENSE SNOW COULD BE RESULTING IN SOME ISOLATED BRIEF
PERIODS OF SUB MILE VISIBILITIES. OVERALL...NOT MUCH HAS CHANGED WITH
THE THINKING OF THIS SNOW. THIS BAND OF SNOW SHOULD GRADUALLY SAG
SOUTHWARD OVER THE NEXT FEW HOURS...LIKELY ENDING ACROSS MY SOUTHERN
COUNTIES AROUND OR SHORTLY AFTER DAYBREAK. SO...ALTHOUGH THE SNOW IS
FALLING AT A DECENT RATE...IT APPEARS THAT OVERALL SNOW
ACCUMULATIONS SHOULD REMAIN AROUND AN INCH OR LESS.
IN ADDITION TO THE MAIN BAND OF SNOW...THERE IS ACTUALLY ALSO SOME
LIGHT LAKE EFFECT LIGHT SNOW SHOWERS/FLURRIES DEVELOPING ACROSS
SOUTHEASTERN WISCONSIN. THE COLD AIRMASS SPILLING ACROSS THE LAKE IS
PRODUCING SOME MODEST LAKE INDUCED EL`S UP AROUND 4,000 FEET
AGL...PER MODEL BUFKIT SOUNDINGS. ALTHOUGH THIS WILL NOT BE A BIG
DEAL...THERE MAY BE A FEW ADDITIONAL LIGHT SNOW FLURRIES ACROSS
NORTHEASTERN ILLINOIS THROUGH MID MORNING BEFORE THINGS BEGIN TO
CLEAR OUT. I ADDED A FEW ISOLATED FLURRIES TO THE FORECAST TO ACCOUNT
FOR THIS ACTIVITY.
OTHERWISE...THE MAIN STORY TODAY WILL BE THE RETURN TO UNSEASONABLY
COLD WEATHER. WINDS WILL REMAIN NORTHEASTERLY BETWEEN 15 TO 25 MPH
TODAY AS A STORM SYSTEM MOVES ACROSS THE LOWER MISSISSIPPI VALLEY
AND A COLD CANADIAN HIGH SETTLES SOUTHEASTWARD ACROSS WISCONSIN.
THIS WILL CONTINUE TO DRIVE A MUCH COLDER AIRMASS IN ACROSS THE
REGION...AND AS SUCH...THIS WILL RESULT IN COLD RAW DAY ACROSS THE
REGION. I HAVE REMAINED A BIT HIGHER THAN MOST GUIDANCE ON HIGH
TEMPERATURES TODAY. THIS IS MAINLY DUE TO THE FACT THAT LOCAL
CLIMATOLOGY FOR 925 MB TEMPERATURES SUGGESTS THAT TEMPERATURES
COULD BE A TOUCH WARMER THAN WHAT GUIDANCE SUGGESTS. HOWEVER...THIS
WILL NOT CHANGE THE FACT THAT IT WILL STILL BE A COLD DAY.
THE SURFACE RIDGE AXIS IS EXPECTED TO SHIFT OVER THE AREA
TONIGHT...SETTING UP LIGHTER WINDS...AND LIKELY A VERY COLD NIGHT
ACROSS THE AREA. SOME HIGHER CLOUDS MAY TRY TO MOVE ACROSS THE AREA
LATE TONIGHT...BUT OVERALL...IT APPEARS THAT SKIES SHOULD REMAIN
MOSTLY CLEAR TO PARTLY CLOUDY...AND THIS SHOULD ALLOW TEMPERATURES
TO DROP INTO THE TEENS IN MOST AREAS. SOME SINGLE DIGIT TEMPERATURES
ARE EVEN POSSIBLE IN THE CLIMATOLOGICALLY FAVORED AREAS.
A WARMER AIRMASS WILL BEGIN TO ADVECT NORTHWARD AGAIN LATER IN
THE DAY MONDAY. SO TEMPERATURES WILL BEGIN A REBOUND DURING THE
DAY. HOWEVER...THE BETTER WARMTH WILL NOT SET UP UNTIL TUESDAY. AN
ACTIVE STORM TRACK WILL LEAD TO ANOTHER STORM SYSTEM SETTING UP
ACROSS THE CENTRAL AND NORTHERN PLAINS ON MONDAY. THIS WILL FORCE
MUCH WARMER AIR TO LIFT NORTHWARD ACROSS THE MISSISSIPPI VALLEY
AND INTO THE GREAT LAKES REGION INTO TUESDAY. THERE CONTINUES TO
BE DIFFERENCES IN THE TRACK AND TIMING OF THIS SYSTEM INTO MID
WEEK. HOWEVER...OVERALL...PREFER THE SLOWER SOLUTIONS GIVEN THE
AMPLITUDE OF THE SYSTEM. THIS SHOULD RESULT IN A FAIRLY WARM DAY
FOR MOST OF THE REGION TUESDAY...WITH TEMPERATURES LOOKING TO BE
WELL INTO THE 50S...ESPECIALLY AWAY FROM THE LAKE. HOWEVER...IT
APPEARS AREAS ACROSS NORTHEASTERN ILLINOIS WILL BE MUCH
COOLER...LIKELY IN THE LOWER 40S...DUE TO AN EASTERLY WIND
COMPONENT OFF THE LAKE.
THE STORM SYSTEM LOOKS TO MOVE SOMEWHERE ACROSS SOUTHERN WISCONSIN
EARLY WEDNESDAY MORNING. THIS TIMING AND TRACK WOULD FAVOR THE BEST
CHANCES OF RAIN FOR THE AREA LATER TUESDAY NIGHT THROUGH WEDNESDAY
MORNING. IT APPEARS THAT THE REGION WILL REMAIN IN THE WARM SECTOR
TUESDAY NIGHT...RESULTING IN A VERY MILD NIGHT...POTENTIALLY EVEN
WARMER THAN THE CURRENT FORECAST SUGGESTS. THEREFORE...THE THREAT
FOR ANY SNOW SHOULD REMAIN WELL NORTH OF THE AREA. COOLER AIR WILL
MOVE ACROSS THE REGION FOLLOWING THE COLD FRONTAL PASSAGE WEDNESDAY
MORNING.
THE ACTIVE STORM TRACK APPEARS THAT IT COULD PRODUCE AND DRIVE YET
ANOTHER STORM SYSTEM ACROSS THE AREA SOMETIME LATE IN THE WEEK
AROUND FRIDAY. HOWEVER...THERE ARE EVEN LARGER DISCREPANCIES WITH
AMONGST THE FORECAST GUIDANCE WITH THE EVOLUTION AND TIMING OF THIS
SYSTEM. SO OVERALL CONFIDENCE IS FAIRLY LOW. THIS COULD RESULT IN
OUR NEXT CHANCE OF PRECIPITATION...AS WELL AS CHANCES FOR WARMER
WEATHER INTO FRIDAY...BEFORE ANOTHER SHOT OF COLDER AIR DROPS BACK
ACROSS THE REGION INTO NEXT WEEKEND.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* LOW POTENTIAL FOR MVFR CIGS/FLURRIES TO RETURN THIS
AFTERNOON/EVENING
* GUSTY NORTHEASTERLY WINDS...TAPERING IN THE EVENING
BMD
//DISCUSSION...UPDATED 18Z...
HIGH PRESSURE EXTENDS FROM LAKE SUPERIOR INTO THE MID MISSOURI
VALLEY THIS AFTERNOON AND WILL SLOWLY SAG SOUTHEAST OVER THE AREA
THIS EVENING AND TONIGHT. AHEAD OF THE RIDGE AXIS THOUGH...GUSTY
NORTHEASTERLY WINDS WILL PERSIST THROUGH THE AFTERNOON...BUT SHOULD
GRADUALLY TREND DOWN. OUT THE GATE...GUSTS INTO THE MID 20 KT RANGE
ARE EXPECTED. LAKE EFFECT MVFR CIGS/FLURRIES WHICH HAVE IMPACTED
PORTIONS OF NORTHERN ILLINOIS THROUGH THE MORNING SHOULD GRADUALLY
LIFT NORTH AND DIMINISH AS DRIER AIR MOVES INTO THE REGION. SOME
MODELS DO SUGGEST CIGS REFORMING BACK OVER THE CHICAGO AREA THIS
EVENING...BUT CONFIDENCE IN THIS HAPPENING IS LOW AT THIS TIME.
SHORTLY AFTER SUNSET...WINDS SHOULD DROP BELOW 10 KTS AND BEGIN TO
VEER TOWARDS THE SOUTHEAST AS THE RIDGE AXIS PUSHES THROUGH THE
AREA. EXCEPT FOR THE POTENTIAL WINDOW OF MVFR THIS EVENING...VFR
CONDITIONS WILL OTHERWISE PREVAIL THROUGH THE TAF PERIOD.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* LOW CONFIDENCE IN MVFR RETURNING THIS EVENING
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...VFR. MODERATELY STRONG SE WINDS POSSIBLE. -SHRA POSSIBLE
AT NIGHT.
WEDNESDAY...MVFR CIGS LIKELY. STRONG/GUSTY WEST WINDS.
THURSDAY...VFR.
FRIDAY...CHANCE OF -RA. MVFR CIGS POSSIBLE.
SATURDAY...VFR PROBABLE.
IZZI
&&
.MARINE...
227 PM CDT
HEADLINES...EXTENDED THE SMALL CRAFT ADVISORY FOR POINTS WEST OF
GARY UNTIL 9Z TONIGHT AS THE WAVE MODEL CONTINUES TO INDICATE
HAZARDOUS WAVES WILL PERSIST A BIT LONGER. WILL NEED A GALE WATCH
FOR WEDNESDAY MORNING THROUGH WEDNESDAY EVENING BUT ITS A BIT FAR
OUT TO BE NAILING DOWN EXACT TIMES NOW. WILL ALSO LIKELY NEED A
SMALL CRAFT ADVISORY FOR TUESDAY AFTERNOON THROUGH WEDNESDAY EVENING
FOR BOTH WINDS AND WAVES.
HIGH PRESSURE IS OVER THE NORTHERN PART OF THE LAKE NOW...BUT STILL
HAVE NE WINDS 20-25 KT OVER THE SW END OF THE LAKE. WINDS WILL
CONTINUE TO DIMINISH AS THE HIGH SHIFTS EAST AND ITS RIDGE ROTATES
OVER THE LAKE. WINDS BECOME SE TOMORROW MORNING AND REMAIN SE
THROUGH TUESDAY AFTERNOON. WINDS PICK UP AND BEGIN TO VEER TO SOUTH
TUESDAY EVENING AHEAD OF THE NEXT LOW. GUIDANCE HAS SOME
DIFFERENCES WITH THE LOW...BUT THINKING THE LOW WILL DEEPEN SLIGHTLY
AS IT MOVES OVER THE LAKE WEDNESDAY. AS SUCH EXPECTING SW TO W GALES
WEDNESDAY. WINDS REMAIN WEST BEHIND THE LOW BUT QUICKLY DIMINISH AS
A WEAK HIGH PRESSURE RIDGE MOVES OVER THE LAKE THURSDAY. WINDS THEN
TURN EAST AS YET ANOTHER LOW IS CURRENTLY PROGGED TO PASS JUST SOUTH
OF THE LAKE FRIDAY.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 9 PM SUNDAY.
SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO GARY IN UNTIL 4 AM
MONDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
1239 PM CDT Sun Mar 16 2014
.DISCUSSION...
ISSUED 1039 AM CDT Sun Mar 16 2014
Latest radar imagery continues to show a band of frontogenetically
forced snow dissipating across the Illinois River Valley. The
snow currently extends along a line from near El Paso, to Pekin,
to Rushville and is shifting slowly southeastward. While earlier
model data suggested snow would be completely gone by 10am, it
appears light snow/flurries will persist through noon before dry
northeasterly flow finally erodes the precip. Meanwhile, southern
stream wave is spreading rain northward into the Ohio River
Valley: however, precip is having a hard time fighting against the
dry NE flow. Models keep most of the precip just south of the KILX
CWA this afternoon, with only the far SE potentially being
impacted. Have tightened the POP gradient across the E/SE, mainly
to limit any mention of precip to only locations south of I-70.
Even though mostly rain is falling across southern Illinois at
this time, ample dry air within the atmospheric column will lead
to evaporative cooling and snow if the precip makes it into the SE
CWA. Will maintain chance POPs south of I-70, with perhaps around
one half inch of slushy snow accumulation along/south of Highway
50.
Barnes
&&
.AVIATION...
ISSUED 1239 PM CDT Sun Mar 16 2014
VFR conditions will prevail through the entire 18z TAF period.
Strong northeasterly winds will continue throughout the afternoon,
with gusts generally in the 25 to 30kt range. Gustiness will
subside toward sunset, with winds decreasing to less than 10kt
overnight as high pressure builds into the region. Once high
shifts off to the east, a light E/SE return flow will develop
by Monday morning. Mid/high cloud deck will remain in place this
afternoon, but will gradually shift southeastward with time and
should be south of the terminals by early evening. May see a few
lake-enhanced lower clouds around 2500ft at KPIA, but do not
expect any prevailing MVFR ceilings at this time.
Barnes
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Sun Mar 16 2014
SHORT TERM...Today through Thursday
00Z models continue to trend further south with surface low
pressure and associated qpf fields over southern areas today.
Therefore continue to lower pops and qpf/snowfall amounts over
southern counties today. A light snow band nw of the IL river has
produced between a half to 1 inch the past several hours from Knox,
Stark and Marshall counties nw toward the Quad Cities. RUC/HRRR
models diminish this light snow band over the IL river valley
through mid morning/15Z and any additional snow accumulations
should be less than 1 inch as it weakens.
1003 mb low pressure over west central AR while 1037 mb high
pressure was near the MN/Canadian border. Very tight pressure
gradient over IL between these systems giving gusty ne winds as
high as 35 to 43 mph over central IL early this morning. RUC and
NAM models show these higher wind gusts of 35-45 mph shifting
ssw by midday so strongest winds over central IL during the
morning and not quite as strong in the afternoon hours. Still
think shy of wind advisory criteria though a few spots could reach
sustained around 30 mph or a bit higher and/or wind gusts near 45
mph. Low pressure to track east across northern MS/AL today and
keep brunt of heavier pcpn south of IL. Have chance of mixed
precip this morning southern areas and mainly just chance of light
snow se IL this afternoon and ending by late today as low pressure
system pulls away from IL.
Much colder today and little temperature rise and se IL may even
see temps slipping during the day into the lower 30s. Clouds
decreasing over the IL river valley this afternoon and over rest
of area during the evening with diminishing winds. Cold lows in
the mid to upper teens tonight with southeast IL around 20F.
Nice warmup in store Mon and especially Tue with upper 50s and
lower 60s possible Tue afternoon. 995 mb low pressure passes nw of
IL Tue night and brings a cold front east through the state with
chance of rain showers and diminishing already during Wed. Temps
cool just a bit behind this system Wed/Thu but still could see
highs in upper 40s to mid 50s.
LONG TERM...Thursday night through Sunday
Milder temps return Friday with breezy southerly winds and highs
back into the upper 50s and lower 60s with even mid 60s se of I-70.
Low pressure passes to north of central IL again Fri/Fri night
brining a cold front through Friday night and next chance of rain
showers Fri and Fri night. Canadian high pressure building down
into the Midwest this weekend to bring colder temperatures back to
the region.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1105 AM CDT SUN MAR 16 2014
.DISCUSSION...
1025 AM CDT
FOR MORNING UPDATE...
MADE SOME CHANGES TO FORECAST TODAY MAINLY FOR LAKE EFFECT
FLURRIES/LIGHT SNOW SHOWERS OVER PARTS OF FAR NORTH/NORTHEAST IL...
AND TWEAKS TO MAINTAIN SOME MENTION OF WEAKENING LIGHT SNOW/FLURRIES
ACROSS THE FAR SOUTH INTO EARLY THIS AFTERNOON.
15Z SURFACE ANALYSIS DEPICTS HIGH PRESSURE OVER THE NORTHERN GREAT
LAKES...WHILE FARTHER SOUTH AN AREA OF LOW PRESSURE WAS OVER THE
LOWER MISSISSIPPI VALLEY. THIS LOW WAS ASSOCIATED WITH A FAIRLY DEEP
SHORT WAVE TROUGH NOTED OVER THAT REGION IN MORNING GOES WATER VAPOR
IMAGERY. THE PRECIPITATION SHIELD FROM THE LOW PRESSURE SYSTEM
EXTENDED ACROSS MUCH OF SOUTHERN MISSOURI INTO PARTS OF CENTRAL AND
SOUTHERN IL/INDIANA...THOUGH A NARROW WEAKENING BAND OF LIGHT SNOW
HAD PERSISTED EVEN FARTHER NORTH ROUGHLY ALONG A LINE ROUGHLY FROM
QUINCY-MACOMB-MORRIS. THIS BAND OF SNOW HAD PRODUCED HIGHER
REFLECTIVITY RADAR RETURNS JUST OFF TO THE SOUTHWEST OF THE CWA...
THOUGH HAS WEAKENED STEADILY OVER THE PAST FEW HOURS. STILL...HAVE
INDICATED SOME LOWER CHANCE POPS FOR LIGHT SNOW/FLURRIES ACROSS THE
FAR SOUTH CWA INTO EARLY AFTERNOON AS THIS BAND CONTINUES TO
DISSIPATE AND DRIFT SOUTHEAST.
ACROSS FAR NORTHERN IL...COLD LOW LEVEL NORTHEAST FLOW OFF LAKE
MICHIGAN WAS PRODUCING AND AREA OF LAKE-INDUCED FLURRIES AND SNOW
SHOWERS...PARTICULARLY ACROSS SE WI AND IL COUNTIES ADJACENT TO THE
STATE LINE. FORECAST SOUNDINGS MAINTAIN NORTHEAST WIND FIELD THROUGH
THE DAY...GRADUALLY WEAKENING AND VEERING MORE EAST IN THE LOW
LEVELS TOWARD EVENING. THIS WOULD SUGGEST MAINTAINING A THREAT OF
SOME LIGHT SNOW SHOWERS ACROSS THESE SAME AREAS. HOWEVER...ADVECTION
OF DRY LOW LEVEL AIR APPEARS TO BE RESULTING IN A DECREASE IN DEPTH
OF LAKE-EFFECT STRATOCU PER GOES VISIBLE LOOP...AND HIGH-RES
GUIDANCE INCLUDING OUR LOCAL 8 KM ARW INDICATE DECREASING RH IN THE
CLOUD BEARING LAYER THROUGH THIS AFTERNOON. THUS HAVE INDICATED
DECREASING POPS FOR SNOW SHOWERS LATE THIS MORNING...DIMINISHING TO
SCATTERED FLURRIES ACROSS FAR NORTH/NORTHEAST IL INTO THIS
AFTERNOON.
OTHER THAN SOME ACCOMPANYING TWEAKS TO SKY COVER COINCIDENT WITH
POP/WX ADJUSTMENTS...REMAINDER OF FORECAST APPEARS IN GOOD SHAPE AT
THIS TIME AND NO OTHER CHANGES MADE THROUGH THIS EVENING.
RATZER
//PREV DISCUSSION...
322 AM CDT
THE MAIN FORECAST CONCERNS CENTER MAINLY AROUND TEMPERATURES THROUGH
THE PERIOD...WITH A TYPICAL SPRING SEE SAW PATTERN OF WARMER PERIODS
FOLLOWED BY COOLER PERIODS THROUGH THE UPCOMING WEEK.
A DECENT AREA OF SNOW HAS DEVELOPED ACROSS IOWA AND NORTHERN
ILLINOIS OVERNIGHT. THIS BAND OF SNOW IS ASSOCIATED WITH A STRONG
BAND OF FRONTOGENESIS THAT EXISTS WITHIN THE FAVORABLE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET STREAK ACROSS THE GREAT LAKES. RADAR
RETURNS SUGGEST THAT THIS BAND OF SNOW IS FAIRLY INTENSE ACROSS
PORTIONS OF THE I-80 CORRIDOR AS OF THIS WRITING. VISIBILITIES UNDER
THIS BAND OF SNOW RANGE FROM AROUND 1 TO 2 MILES. HOWEVER...SOME OF
THE MORE INTENSE SNOW COULD BE RESULTING IN SOME ISOLATED BRIEF
PERIODS OF SUB MILE VISIBILITIES. OVERALL...NOT MUCH HAS CHANGED WITH
THE THINKING OF THIS SNOW. THIS BAND OF SNOW SHOULD GRADUALLY SAG
SOUTHWARD OVER THE NEXT FEW HOURS...LIKELY ENDING ACROSS MY SOUTHERN
COUNTIES AROUND OR SHORTLY AFTER DAYBREAK. SO...ALTHOUGH THE SNOW IS
FALLING AT A DECENT RATE...IT APPEARS THAT OVERALL SNOW
ACCUMULATIONS SHOULD REMAIN AROUND AN INCH OR LESS.
IN ADDITION TO THE MAIN BAND OF SNOW...THERE IS ACTUALLY ALSO SOME
LIGHT LAKE EFFECT LIGHT SNOW SHOWERS/FLURRIES DEVELOPING ACROSS
SOUTHEASTERN WISCONSIN. THE COLD AIRMASS SPILLING ACROSS THE LAKE IS
PRODUCING SOME MODEST LAKE INDUCED EL`S UP AROUND 4,000 FEET
AGL...PER MODEL BUFKIT SOUNDINGS. ALTHOUGH THIS WILL NOT BE A BIG
DEAL...THERE MAY BE A FEW ADDITIONAL LIGHT SNOW FLURRIES ACROSS
NORTHEASTERN ILLINOIS THROUGH MID MORNING BEFORE THINGS BEGIN TO
CLEAR OUT. I ADDED A FEW ISOLATED FLURRIES TO THE FORECAST TO ACCOUNT
FOR THIS ACTIVITY.
OTHERWISE...THE MAIN STORY TODAY WILL BE THE RETURN TO UNSEASONABLY
COLD WEATHER. WINDS WILL REMAIN NORTHEASTERLY BETWEEN 15 TO 25 MPH
TODAY AS A STORM SYSTEM MOVES ACROSS THE LOWER MISSISSIPPI VALLEY
AND A COLD CANADIAN HIGH SETTLES SOUTHEASTWARD ACROSS WISCONSIN.
THIS WILL CONTINUE TO DRIVE A MUCH COLDER AIRMASS IN ACROSS THE
REGION...AND AS SUCH...THIS WILL RESULT IN COLD RAW DAY ACROSS THE
REGION. I HAVE REMAINED A BIT HIGHER THAN MOST GUIDANCE ON HIGH
TEMPERATURES TODAY. THIS IS MAINLY DUE TO THE FACT THAT LOCAL
CLIMATOLOGY FOR 925 MB TEMPERATURES SUGGESTS THAT TEMPERATURES
COULD BE A TOUCH WARMER THAN WHAT GUIDANCE SUGGESTS. HOWEVER...THIS
WILL NOT CHANGE THE FACT THAT IT WILL STILL BE A COLD DAY.
THE SURFACE RIDGE AXIS IS EXPECTED TO SHIFT OVER THE AREA
TONIGHT...SETTING UP LIGHTER WINDS...AND LIKELY A VERY COLD NIGHT
ACROSS THE AREA. SOME HIGHER CLOUDS MAY TRY TO MOVE ACROSS THE AREA
LATE TONIGHT...BUT OVERALL...IT APPEARS THAT SKIES SHOULD REMAIN
MOSTLY CLEAR TO PARTLY CLOUDY...AND THIS SHOULD ALLOW TEMPERATURES
TO DROP INTO THE TEENS IN MOST AREAS. SOME SINGLE DIGIT TEMPERATURES
ARE EVEN POSSIBLE IN THE CLIMATOLOGICALLY FAVORED AREAS.
A WARMER AIRMASS WILL BEGIN TO ADVECT NORTHWARD AGAIN LATER IN
THE DAY MONDAY. SO TEMPERATURES WILL BEGIN A REBOUND DURING THE
DAY. HOWEVER...THE BETTER WARMTH WILL NOT SET UP UNTIL TUESDAY. AN
ACTIVE STORM TRACK WILL LEAD TO ANOTHER STORM SYSTEM SETTING UP
ACROSS THE CENTRAL AND NORTHERN PLAINS ON MONDAY. THIS WILL FORCE
MUCH WARMER AIR TO LIFT NORTHWARD ACROSS THE MISSISSIPPI VALLEY
AND INTO THE GREAT LAKES REGION INTO TUESDAY. THERE CONTINUES TO
BE DIFFERENCES IN THE TRACK AND TIMING OF THIS SYSTEM INTO MID
WEEK. HOWEVER...OVERALL...PREFER THE SLOWER SOLUTIONS GIVEN THE
AMPLITUDE OF THE SYSTEM. THIS SHOULD RESULT IN A FAIRLY WARM DAY
FOR MOST OF THE REGION TUESDAY...WITH TEMPERATURES LOOKING TO BE
WELL INTO THE 50S...ESPECIALLY AWAY FROM THE LAKE. HOWEVER...IT
APPEARS AREAS ACROSS NORTHEASTERN ILLINOIS WILL BE MUCH
COOLER...LIKELY IN THE LOWER 40S...DUE TO AN EASTERLY WIND
COMPONENT OFF THE LAKE.
THE STORM SYSTEM LOOKS TO MOVE SOMEWHERE ACROSS SOUTHERN WISCONSIN
EARLY WEDNESDAY MORNING. THIS TIMING AND TRACK WOULD FAVOR THE BEST
CHANCES OF RAIN FOR THE AREA LATER TUESDAY NIGHT THROUGH WEDNESDAY
MORNING. IT APPEARS THAT THE REGION WILL REMAIN IN THE WARM SECTOR
TUESDAY NIGHT...RESULTING IN A VERY MILD NIGHT...POTENTIALLY EVEN
WARMER THAN THE CURRENT FORECAST SUGGESTS. THEREFORE...THE THREAT
FOR ANY SNOW SHOULD REMAIN WELL NORTH OF THE AREA. COOLER AIR WILL
MOVE ACROSS THE REGION FOLLOWING THE COLD FRONTAL PASSAGE WEDNESDAY
MORNING.
THE ACTIVE STORM TRACK APPEARS THAT IT COULD PRODUCE AND DRIVE YET
ANOTHER STORM SYSTEM ACROSS THE AREA SOMETIME LATE IN THE WEEK
AROUND FRIDAY. HOWEVER...THERE ARE EVEN LARGER DISCREPANCIES WITH
AMONGST THE FORECAST GUIDANCE WITH THE EVOLUTION AND TIMING OF THIS
SYSTEM. SO OVERALL CONFIDENCE IS FAIRLY LOW. THIS COULD RESULT IN
OUR NEXT CHANCE OF PRECIPITATION...AS WELL AS CHANCES FOR WARMER
WEATHER INTO FRIDAY...BEFORE ANOTHER SHOT OF COLDER AIR DROPS BACK
ACROSS THE REGION INTO NEXT WEEKEND.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* MODERATELY STRONG/GUSTY NE WINDS THROUGH THIS AFTERNOON
* SMALL CHANCE OF LAKE EFFECT MVFR CIGS THIS AFTERNOON/EVENING
IZZI/BMD
//DISCUSSION...UPDATED 12Z...
SYNOPTIC SNOWS HAVE GENERALLY SHIFTED SOUTH OF THE TERMINALS...BUT
CLOUDS AND SOME FLURRIES CONTINUE TO STREAM INTO NORTHERN ILLINOIS
OFF THE LAKE. AXIS OF CLOUDS/FLURRIES WILL PROBABLY PIVOT
NORTHWARD THIS MORNING AND PROBABLY NORTH OF ORD/DPA AND
EVENTUALLY RFD...IF NOT DRIER AIR UPSTREAM COULD LIMIT CLOUD
DEVELOPMENT SOME. OVERALL CONFIDENCE IN WHEN/IF MVFR CIGS CLEAR
IS LOW. NORTHEAST WINDS SHOULD REMAIN RATHER STRONG WITH GUSTS IN
THE 20-30KT RANGE THIS MORNING PROBABLY EASING TO CLOSER TO 20KT
THIS AFTERNOON...BEFORE QUICKLY DIMINISHING AND LOSING GUSTS EARLY
THIS EVENING.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* LOW CONFIDENCE IN MVFR CIG TRENDS TODAY
* HIGH CONFIDENCE IN OTHER ELEMENTS
IZZI/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...VFR. MODERATELY STRONG SE WINDS POSSIBLE. -SHRA POSSIBLE
AT NIGHT.
WEDNESDAY...MVFR CIGS LIKELY. STRONG/GUSTY WEST WINDS.
THURSDAY...VFR.
FRIDAY...CHANCE OF -RA. MVFR CIGS POSSIBLE.
SATURDAY...VFR PROBABLE.
IZZI
&&
.MARINE...
251 AM CDT
FAIRLY STRONG NORTHEAST WINDS TO JUST BELOW GALE FORCE THIS
MORNING OVER THE SOUTH THIRD OF THE LAKE SHOULD BEGIN TO EASE THIS
AFTERNOON AND ESPECIALLY TONIGHT AS HIGH PRESSURE INCHES CLOSER TO
REGION AND LOW PRESSURE TO OUR SOUTH SCOOTS OFF TO THE EAST.
SOUTHEASTERLY WINDS SHOULD DEVELOP AND GRADUALLY FRESHEN UP MONDAY
NIGHT THROUGH TUESDAY NIGHT IN ADVANCE OF THE NEXT LOW. FAIRLY
STRONG LOW AND FORMIDABLE SHOT OF COLD AIR BEHIND IT COULD ALLOW
FOR A PERIOD OF WESTERLY GALES WEDNESDAY BEFORE WINDS SLACKEN A
BIT LATE IN THE WEEK.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 9 PM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
National Weather Service Lincoln IL
1039 AM CDT Sun Mar 16 2014
.DISCUSSION...
ISSUED 1039 AM CDT Sun Mar 16 2014
Latest radar imagery continues to show a band of frontogenetically
forced snow dissipating across the Illinois River Valley. The
snow currently extends along a line from near El Paso, to Pekin,
to Rushville and is shifting slowly southeastward. While earlier
model data suggested snow would be completely gone by 10am, it
appears light snow/flurries will persist through noon before dry
northeasterly flow finally erodes the precip. Meanwhile, southern
stream wave is spreading rain northward into the Ohio River
Valley: however, precip is having a hard time fighting against the
dry NE flow. Models keep most of the precip just south of the KILX
CWA this afternoon, with only the far SE potentially being
impacted. Have tightened the POP gradient across the E/SE, mainly
to limit any mention of precip to only locations south of I-70.
Even though mostly rain is falling across southern Illinois at
this time, ample dry air within the atmospheric column will lead
to evaporative cooling and snow if the precip makes it into the SE
CWA. Will maintain chance POPs south of I-70, with perhaps around
one half inch of slushy snow accumulation along/south of Highway
50.
Barnes
&&
.AVIATION...
ISSUED 655 AM CDT Sun Mar 16 2014
Strong northeast winds the main concern today along with areas of
light snow and briefly lower cigs...especially around Peoria south
to near Springfield this morning. Northeast winds of 25 to 35 mph
with gusts as high as 45 mph at times will continue through this
morning with a gradual decrease in winds this afternoon and esp
this evening as high pressure settles into our area. MVFR cigs
will continue for a few more hours at PIA before conditions start
to improve for late morning thru the afternoon hours. SPI is going
to be right on the edge of the MVFR cigs so for now will continue
with VFR conditions there with snow, if any, expected to be light
enough not to bring the cigs down. VFR conditions are expected
across the entire area tonight as high pressure settles in.
Smith
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Sun Mar 16 2014
SHORT TERM...Today through Thursday
00Z models continue to trend further south with surface low
pressure and associated qpf fields over southern areas today.
Therefore continue to lower pops and qpf/snowfall amounts over
southern counties today. A light snow band nw of the IL river has
produced between a half to 1 inch the past several hours from Knox,
Stark and Marshall counties nw toward the Quad Cities. RUC/HRRR
models diminish this light snow band over the IL river valley
through mid morning/15Z and any additional snow accumulations
should be less than 1 inch as it weakens.
1003 mb low pressure over west central AR while 1037 mb high
pressure was near the MN/Canadian border. Very tight pressure
gradient over IL between these systems giving gusty ne winds as
high as 35 to 43 mph over central IL early this morning. RUC and
NAM models show these higher wind gusts of 35-45 mph shifting
ssw by midday so strongest winds over central IL during the
morning and not quite as strong in the afternoon hours. Still
think shy of wind advisory criteria though a few spots could reach
sustained around 30 mph or a bit higher and/or wind gusts near 45
mph. Low pressure to track east across northern MS/AL today and
keep brunt of heavier pcpn south of IL. Have chance of mixed
precip this morning southern areas and mainly just chance of light
snow se IL this afternoon and ending by late today as low pressure
system pulls away from IL.
Much colder today and little temperature rise and se IL may even
see temps slipping during the day into the lower 30s. Clouds
decreasing over the IL river valley this afternoon and over rest
of area during the evening with diminishing winds. Cold lows in
the mid to upper teens tonight with southeast IL around 20F.
Nice warmup in store Mon and especially Tue with upper 50s and
lower 60s possible Tue afternoon. 995 mb low pressure passes nw of
IL Tue night and brings a cold front east through the state with
chance of rain showers and diminishing already during Wed. Temps
cool just a bit behind this system Wed/Thu but still could see
highs in upper 40s to mid 50s.
LONG TERM...Thursday night through Sunday
Milder temps return Friday with breezy southerly winds and highs
back into the upper 50s and lower 60s with even mid 60s se of I-70.
Low pressure passes to north of central IL again Fri/Fri night
brining a cold front through Friday night and next chance of rain
showers Fri and Fri night. Canadian high pressure building down
into the Midwest this weekend to bring colder temperatures back to
the region.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
921 AM CDT SUN MAR 16 2014
.DISCUSSION...
322 AM CDT
THE MAIN FORECAST CONCERNS CENTER MAINLY AROUND TEMPERATURES THROUGH
THE PERIOD...WITH A TYPICAL SPRING SEE SAW PATTERN OF WARMER PERIODS
FOLLOWED BY COOLER PERIODS THROUGH THE UPCOMING WEEK.
A DECENT AREA OF SNOW HAS DEVELOPED ACROSS IOWA AND NORTHERN
ILLINOIS OVERNIGHT. THIS BAND OF SNOW IS ASSOCIATED WITH A STRONG
BAND OF FRONTOGENESIS THAT EXISTS WITHIN THE FAVORABLE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET STREAK ACROSS THE GREAT LAKES. RADAR
RETURNS SUGGEST THAT THIS BAND OF SNOW IS FAIRLY INTENSE ACROSS
PORTIONS OF THE I-80 CORRIDOR AS OF THIS WRITING. VISIBILITIES UNDER
THIS BAND OF SNOW RANGE FROM AROUND 1 TO 2 MILES. HOWEVER...SOME OF
THE MORE INTENSE SNOW COULD BE RESULTING IN SOME ISOLATED BRIEF
PERIODS OF SUB MILE VISIBILITIES. OVERALL...NOT MUCH HAS CHANGED WITH
THE THINKING OF THIS SNOW. THIS BAND OF SNOW SHOULD GRADUALLY SAG
SOUTHWARD OVER THE NEXT FEW HOURS...LIKELY ENDING ACROSS MY SOUTHERN
COUNTIES AROUND OR SHORTLY AFTER DAYBREAK. SO...ALTHOUGH THE SNOW IS
FALLING AT A DECENT RATE...IT APPEARS THAT OVERALL SNOW
ACCUMULATIONS SHOULD REMAIN AROUND AN INCH OR LESS.
IN ADDITION TO THE MAIN BAND OF SNOW...THERE IS ACTUALLY ALSO SOME
LIGHT LAKE EFFECT LIGHT SNOW SHOWERS/FLURRIES DEVELOPING ACROSS
SOUTHEASTERN WISCONSIN. THE COLD AIRMASS SPILLING ACROSS THE LAKE IS
PRODUCING SOME MODEST LAKE INDUCED EL`S UP AROUND 4,000 FEET
AGL...PER MODEL BUFKIT SOUNDINGS. ALTHOUGH THIS WILL NOT BE A BIG
DEAL...THERE MAY BE A FEW ADDITIONAL LIGHT SNOW FLURRIES ACROSS
NORTHEASTERN ILLINOIS THROUGH MID MORNING BEFORE THINGS BEGIN TO
CLEAR OUT. I ADDED A FEW ISOLATED FLURRIES TO THE FORECAST TO ACCOUNT
FOR THIS ACTIVITY.
OTHERWISE...THE MAIN STORY TODAY WILL BE THE RETURN TO UNSEASONABLY
COLD WEATHER. WINDS WILL REMAIN NORTHEASTERLY BETWEEN 15 TO 25 MPH
TODAY AS A STORM SYSTEM MOVES ACROSS THE LOWER MISSISSIPPI VALLEY
AND A COLD CANADIAN HIGH SETTLES SOUTHEASTWARD ACROSS WISCONSIN.
THIS WILL CONTINUE TO DRIVE A MUCH COLDER AIRMASS IN ACROSS THE
REGION...AND AS SUCH...THIS WILL RESULT IN COLD RAW DAY ACROSS THE
REGION. I HAVE REMAINED A BIT HIGHER THAN MOST GUIDANCE ON HIGH
TEMPERATURES TODAY. THIS IS MAINLY DUE TO THE FACT THAT LOCAL
CLIMATOLOGY FOR 925 MB TEMPERATURES SUGGESTS THAT TEMPERATURES
COULD BE A TOUCH WARMER THAN WHAT GUIDANCE SUGGESTS. HOWEVER...THIS
WILL NOT CHANGE THE FACT THAT IT WILL STILL BE A COLD DAY.
THE SURFACE RIDGE AXIS IS EXPECTED TO SHIFT OVER THE AREA
TONIGHT...SETTING UP LIGHTER WINDS...AND LIKELY A VERY COLD NIGHT
ACROSS THE AREA. SOME HIGHER CLOUDS MAY TRY TO MOVE ACROSS THE AREA
LATE TONIGHT...BUT OVERALL...IT APPEARS THAT SKIES SHOULD REMAIN
MOSTLY CLEAR TO PARTLY CLOUDY...AND THIS SHOULD ALLOW TEMPERATURES
TO DROP INTO THE TEENS IN MOST AREAS. SOME SINGLE DIGIT TEMPERATURES
ARE EVEN POSSIBLE IN THE CLIMATOLOGICALLY FAVORED AREAS.
A WARMER AIRMASS WILL BEGIN TO ADVECT NORTHWARD AGAIN LATER IN
THE DAY MONDAY. SO TEMPERATURES WILL BEGIN A REBOUND DURING THE
DAY. HOWEVER...THE BETTER WARMTH WILL NOT SET UP UNTIL TUESDAY. AN
ACTIVE STORM TRACK WILL LEAD TO ANOTHER STORM SYSTEM SETTING UP
ACROSS THE CENTRAL AND NORTHERN PLAINS ON MONDAY. THIS WILL FORCE
MUCH WARMER AIR TO LIFT NORTHWARD ACROSS THE MISSISSIPPI VALLEY
AND INTO THE GREAT LAKES REGION INTO TUESDAY. THERE CONTINUES TO
BE DIFFERENCES IN THE TRACK AND TIMING OF THIS SYSTEM INTO MID
WEEK. HOWEVER...OVERALL...PREFER THE SLOWER SOLUTIONS GIVEN THE
AMPLITUDE OF THE SYSTEM. THIS SHOULD RESULT IN A FAIRLY WARM DAY
FOR MOST OF THE REGION TUESDAY...WITH TEMPERATURES LOOKING TO BE
WELL INTO THE 50S...ESPECIALLY AWAY FROM THE LAKE. HOWEVER...IT
APPEARS AREAS ACROSS NORTHEASTERN ILLINOIS WILL BE MUCH
COOLER...LIKELY IN THE LOWER 40S...DUE TO AN EASTERLY WIND
COMPONENT OFF THE LAKE.
THE STORM SYSTEM LOOKS TO MOVE SOMEWHERE ACROSS SOUTHERN WISCONSIN
EARLY WEDNESDAY MORNING. THIS TIMING AND TRACK WOULD FAVOR THE BEST
CHANCES OF RAIN FOR THE AREA LATER TUESDAY NIGHT THROUGH WEDNESDAY
MORNING. IT APPEARS THAT THE REGION WILL REMAIN IN THE WARM SECTOR
TUESDAY NIGHT...RESULTING IN A VERY MILD NIGHT...POTENTIALLY EVEN
WARMER THAN THE CURRENT FORECAST SUGGESTS. THEREFORE...THE THREAT
FOR ANY SNOW SHOULD REMAIN WELL NORTH OF THE AREA. COOLER AIR WILL
MOVE ACROSS THE REGION FOLLOWING THE COLD FRONTAL PASSAGE WEDNESDAY
MORNING.
THE ACTIVE STORM TRACK APPEARS THAT IT COULD PRODUCE AND DRIVE YET
ANOTHER STORM SYSTEM ACROSS THE AREA SOMETIME LATE IN THE WEEK
AROUND FRIDAY. HOWEVER...THERE ARE EVEN LARGER DISCREPANCIES WITH
AMONGST THE FORECAST GUIDANCE WITH THE EVOLUTION AND TIMING OF THIS
SYSTEM. SO OVERALL CONFIDENCE IS FAIRLY LOW. THIS COULD RESULT IN
OUR NEXT CHANCE OF PRECIPITATION...AS WELL AS CHANCES FOR WARMER
WEATHER INTO FRIDAY...BEFORE ANOTHER SHOT OF COLDER AIR DROPS BACK
ACROSS THE REGION INTO NEXT WEEKEND.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* MODERATELY STRONG/GUSTY NE WINDS THROUGH THIS AFTERNOON
* LAKE EFFECT MVFR CIGS LINGERING THROUGH MORNING AT ORD
* SMALL CHANCE OF LAKE EFFECT MVFR CIGS THIS AFTERNOON/EVENING
IZZI/BMD
//DISCUSSION...UPDATED 12Z...
SYNOPTIC SNOWS HAVE GENERALLY SHIFTED SOUTH OF THE TERMINALS...BUT
CLOUDS AND SOME FLURRIES CONTINUE TO STREAM INTO NORTHERN ILLINOIS
OFF THE LAKE. AXIS OF CLOUDS/FLURRIES WILL PROBABLY PIVOT
NORTHWARD THIS MORNING AND PROBABLY NORTH OF ORD/DPA AND
EVENTUALLY RFD...IF NOT DRIER AIR UPSTREAM COULD LIMIT CLOUD
DEVELOPMENT SOME. OVERALL CONFIDENCE IN WHEN/IF MVFR CIGS CLEAR
IS LOW. NORTHEAST WINDS SHOULD REMAIN RATHER STRONG WITH GUSTS IN
THE 20-30KT RANGE THIS MORNING PROBABLY EASING TO CLOSER TO 20KT
THIS AFTERNOON...BEFORE QUICKLY DIMINISHING AND LOSING GUSTS EARLY
THIS EVENING.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* LOW CONFIDENCE IN MVFR CIG TRENDS TODAY
* HIGH CONFIDENCE IN OTHER ELEMENTS
IZZI/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...VFR. MODERATELY STRONG SE WINDS POSSIBLE. -SHRA POSSIBLE
AT NIGHT.
WEDNESDAY...MVFR CIGS LIKELY. STRONG/GUSTY WEST WINDS.
THURSDAY...VFR.
FRIDAY...CHANCE OF -RA. MVFR CIGS POSSIBLE.
SATURDAY...VFR PROBABLE.
IZZI
&&
.MARINE...
251 AM CDT
FAIRLY STRONG NORTHEAST WINDS TO JUST BELOW GALE FORCE THIS
MORNING OVER THE SOUTH THIRD OF THE LAKE SHOULD BEGIN TO EASE THIS
AFTERNOON AND ESPECIALLY TONIGHT AS HIGH PRESSURE INCHES CLOSER TO
REGION AND LOW PRESSURE TO OUR SOUTH SCOOTS OFF TO THE EAST.
SOUTHEASTERLY WINDS SHOULD DEVELOP AND GRADUALLY FRESHEN UP MONDAY
NIGHT THROUGH TUESDAY NIGHT IN ADVANCE OF THE NEXT LOW. FAIRLY
STRONG LOW AND FORMIDABLE SHOT OF COLD AIR BEHIND IT COULD ALLOW
FOR A PERIOD OF WESTERLY GALES WEDNESDAY BEFORE WINDS SLACKEN A
BIT LATE IN THE WEEK.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 9 PM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
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Area Forecast Discussion
National Weather Service Lincoln IL
702 AM CDT Sun Mar 16 2014
.DISCUSSION...
ISSUED 330 AM CDT Sun Mar 16 2014
SHORT TERM...Today through Thursday
00Z models continue to trend further south with surface low
pressure and associated qpf fields over southern areas today.
Therefore continue to lower pops and qpf/snowfall amounts over
southern counties today. A light snow band nw of the IL river has
produced between a half to 1 inch the past several hours from Knox,
Stark and Marshall counties nw toward the Quad Cities. RUC/HRRR
models diminish this light snow band over the IL river valley
through mid morning/15Z and any additional snow accumulations
should be less than 1 inch as it weakens.
1003 mb low pressure over west central AR while 1037 mb high
pressure was near the MN/Canadian border. Very tight pressure
gradient over IL between these systems giving gusty ne winds as
high as 35 to 43 mph over central IL early this morning. RUC and
NAM models show these higher wind gusts of 35-45 mph shifting
ssw by midday so strongest winds over central IL during the
morning and not quite as strong in the afternoon hours. Still
think shy of wind advisory criteria though a few spots could reach
sustained around 30 mph or a bit higher and/or wind gusts near 45
mph. Low pressure to track east across northern MS/AL today and
keep brunt of heavier pcpn south of IL. Have chance of mixed
precip this morning southern areas and mainly just chance of light
snow se IL this afternoon and ending by late today as low pressure
system pulls away from IL.
Much colder today and little temperature rise and se IL may even
see temps slipping during the day into the lower 30s. Clouds
decreasing over the IL river valley this afternoon and over rest
of area during the evening with diminishing winds. Cold lows in
the mid to upper teens tonight with southeast IL around 20F.
Nice warmup in store Mon and especially Tue with upper 50s and
lower 60s possible Tue afternoon. 995 mb low pressure passes nw of
IL Tue night and brings a cold front east through the state with
chance of rain showers and diminishing already during Wed. Temps
cool just a bit behind this system Wed/Thu but still could see
highs in upper 40s to mid 50s.
LONG TERM...Thursday night through Sunday
Milder temps return Friday with breezy southerly winds and highs
back into the upper 50s and lower 60s with even mid 60s se of I-70.
Low pressure passes to north of central IL again Fri/Fri night
brining a cold front through Friday night and next chance of rain
showers Fri and Fri night. Canadian high pressure building down
into the Midwest this weekend to bring colder temperatures back to
the region.
07
&&
.AVIATION...
ISSUED 655 AM CDT Sun Mar 16 2014
Strong northeast winds the main concern today along with areas of
light snow and briefly lower cigs...especially around Peoria south
to near Springfield this morning. Northeast winds of 25 to 35 mph
with gusts as high as 45 mph at times will continue through this
morning with a gradual decrease in winds this afternoon and esp
this evening as high pressure settles into our area. MVFR cigs
will continue for a few more hours at PIA before conditions start
to improve for late morning thru the afternoon hours. SPI is going
to be right on the edge of the MVFR cigs so for now will continue
with VFR conditions there with snow, if any, expected to be light
enough not to bring the cigs down. VFR conditions are expected
across the entire area tonight as high pressure settles in.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
448 AM CDT SUN MAR 16 2014
.DISCUSSION...
322 AM CDT
THE MAIN FORECAST CONCERNS CENTER MAINLY AROUND TEMPERATURES THROUGH
THE PERIOD...WITH A TYPICAL SPRING SEE SAW PATTERN OF WARMER PERIODS
FOLLOWED BY COOLER PERIODS THROUGH THE UPCOMING WEEK.
A DECENT AREA OF SNOW HAS DEVELOPED ACROSS IOWA AND NORTHERN
ILLINOIS OVERNIGHT. THIS BAND OF SNOW IS ASSOCIATED WITH A STRONG
BAND OF FRONTOGENESIS THAT EXISTS WITHIN THE FAVORABLE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET STREAK ACROSS THE GREAT LAKES. RADAR
RETURNS SUGGEST THAT THIS BAND OF SNOW IS FAIRLY INTENSE ACROSS
PORTIONS OF THE I-80 CORRIDOR AS OF THIS WRITING. VISIBILITIES UNDER
THIS BAND OF SNOW RANGE FROM AROUND 1 TO 2 MILES. HOWEVER...SOME OF
THE MORE INTENSE SNOW COULD BE RESULTING IN SOME ISOLATED BRIEF
PERIODS OF SUB MILE VISIBILITIES. OVERALL...NOT MUCH HAS CHANGED WITH
THE THINKING OF THIS SNOW. THIS BAND OF SNOW SHOULD GRADUALLY SAG
SOUTHWARD OVER THE NEXT FEW HOURS...LIKELY ENDING ACROSS MY SOUTHERN
COUNTIES AROUND OR SHORTLY AFTER DAYBREAK. SO...ALTHOUGH THE SNOW IS
FALLING AT A DECENT RATE...IT APPEARS THAT OVERALL SNOW
ACCUMULATIONS SHOULD REMAIN AROUND AN INCH OR LESS.
IN ADDITION TO THE MAIN BAND OF SNOW...THERE IS ACTUALLY ALSO SOME
LIGHT LAKE EFFECT LIGHT SNOW SHOWERS/FLURRIES DEVELOPING ACROSS
SOUTHEASTERN WISCONSIN. THE COLD AIRMASS SPILLING ACROSS THE LAKE IS
PRODUCING SOME MODEST LAKE INDUCED EL`S UP AROUND 4,000 FEET
AGL...PER MODEL BUFKIT SOUNDINGS. ALTHOUGH THIS WILL NOT BE A BIG
DEAL...THERE MAY BE A FEW ADDITIONAL LIGHT SNOW FLURRIES ACROSS
NORTHEASTERN ILLINOIS THROUGH MID MORNING BEFORE THINGS BEGIN TO
CLEAR OUT. I ADDED A FEW ISOLATED FLURRIES TO THE FORECAST TO ACCOUNT
FOR THIS ACTIVITY.
OTHERWISE...THE MAIN STORY TODAY WILL BE THE RETURN TO UNSEASONABLY
COLD WEATHER. WINDS WILL REMAIN NORTHEASTERLY BETWEEN 15 TO 25 MPH
TODAY AS A STORM SYSTEM MOVES ACROSS THE LOWER MISSISSIPPI VALLEY
AND A COLD CANADIAN HIGH SETTLES SOUTHEASTWARD ACROSS WISCONSIN.
THIS WILL CONTINUE TO DRIVE A MUCH COLDER AIRMASS IN ACROSS THE
REGION...AND AS SUCH...THIS WILL RESULT IN COLD RAW DAY ACROSS THE
REGION. I HAVE REMAINED A BIT HIGHER THAN MOST GUIDANCE ON HIGH
TEMPERATURES TODAY. THIS IS MAINLY DUE TO THE FACT THAT LOCAL
CLIMATOLOGY FOR 925 MB TEMPERATURES SUGGESTS THAT TEMPERATURES
COULD BE A TOUCH WARMER THAN WHAT GUIDANCE SUGGESTS. HOWEVER...THIS
WILL NOT CHANGE THE FACT THAT IT WILL STILL BE A COLD DAY.
THE SURFACE RIDGE AXIS IS EXPECTED TO SHIFT OVER THE AREA
TONIGHT...SETTING UP LIGHTER WINDS...AND LIKELY A VERY COLD NIGHT
ACROSS THE AREA. SOME HIGHER CLOUDS MAY TRY TO MOVE ACROSS THE AREA
LATE TONIGHT...BUT OVERALL...IT APPEARS THAT SKIES SHOULD REMAIN
MOSTLY CLEAR TO PARTLY CLOUDY...AND THIS SHOULD ALLOW TEMPERATURES
TO DROP INTO THE TEENS IN MOST AREAS. SOME SINGLE DIGIT TEMPERATURES
ARE EVEN POSSIBLE IN THE CLIMATOLOGICALLY FAVORED AREAS.
A WARMER AIRMASS WILL BEGIN TO ADVECT NORTHWARD AGAIN LATER IN
THE DAY MONDAY. SO TEMPERATURES WILL BEGIN A REBOUND DURING THE
DAY. HOWEVER...THE BETTER WARMTH WILL NOT SET UP UNTIL TUESDAY. AN
ACTIVE STORM TRACK WILL LEAD TO ANOTHER STORM SYSTEM SETTING UP
ACROSS THE CENTRAL AND NORTHERN PLAINS ON MONDAY. THIS WILL FORCE
MUCH WARMER AIR TO LIFT NORTHWARD ACROSS THE MISSISSIPPI VALLEY
AND INTO THE GREAT LAKES REGION INTO TUESDAY. THERE CONTINUES TO
BE DIFFERENCES IN THE TRACK AND TIMING OF THIS SYSTEM INTO MID
WEEK. HOWEVER...OVERALL...PREFER THE SLOWER SOLUTIONS GIVEN THE
AMPLITUDE OF THE SYSTEM. THIS SHOULD RESULT IN A FAIRLY WARM DAY
FOR MOST OF THE REGION TUESDAY...WITH TEMPERATURES LOOKING TO BE
WELL INTO THE 50S...ESPECIALLY AWAY FROM THE LAKE. HOWEVER...IT
APPEARS AREAS ACROSS NORTHEASTERN ILLINOIS WILL BE MUCH
COOLER...LIKELY IN THE LOWER 40S...DUE TO AN EASTERLY WIND
COMPONENT OFF THE LAKE.
THE STORM SYSTEM LOOKS TO MOVE SOMEWHERE ACROSS SOUTHERN WISCONSIN
EARLY WEDNESDAY MORNING. THIS TIMING AND TRACK WOULD FAVOR THE BEST
CHANCES OF RAIN FOR THE AREA LATER TUESDAY NIGHT THROUGH WEDNESDAY
MORNING. IT APPEARS THAT THE REGION WILL REMAIN IN THE WARM SECTOR
TUESDAY NIGHT...RESULTING IN A VERY MILD NIGHT...POTENTIALLY EVEN
WARMER THAN THE CURRENT FORECAST SUGGESTS. THEREFORE...THE THREAT
FOR ANY SNOW SHOULD REMAIN WELL NORTH OF THE AREA. COOLER AIR WILL
MOVE ACROSS THE REGION FOLLOWING THE COLD FRONTAL PASSAGE WEDNESDAY
MORNING.
THE ACTIVE STORM TRACK APPEARS THAT IT COULD PRODUCE AND DRIVE YET
ANOTHER STORM SYSTEM ACROSS THE AREA SOMETIME LATE IN THE WEEK
AROUND FRIDAY. HOWEVER...THERE ARE EVEN LARGER DISCREPANCIES WITH
AMONGST THE FORECAST GUIDANCE WITH THE EVOLUTION AND TIMING OF THIS
SYSTEM. SO OVERALL CONFIDENCE IS FAIRLY LOW. THIS COULD RESULT IN
OUR NEXT CHANCE OF PRECIPITATION...AS WELL AS CHANCES FOR WARMER
WEATHER INTO FRIDAY...BEFORE ANOTHER SHOT OF COLDER AIR DROPS BACK
ACROSS THE REGION INTO NEXT WEEKEND.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* LAKE EFFECT MVFR CIGS EXPECTED TO LINGER THROUGH AT LEAST
EARLY/MID MORNING
* MODERATELY STRONG/GUSTY NORTHEAST WINDS THROUGH THIS AFTERNOON
IZZI
//DISCUSSION...UPDATE 09Z...
EXTENSIVE LAKE EFFECT CLOUDINESS AT FL020-025 SHOULD LINGER
THROUGH AT LEAST MID MORNING. THERMODYNAMICALLY IT WILL REMAIN
FAVORABLE INTO THIS AFTERNOON FOR LAKE EFFECT CLOUDINESS...BUT HI
RES MODELS SUGGEST THE FOCUS COULD SHIFT FARTHER NORTH INTO SE WI
AND WITH DRIER AIR FILTERING IN ITS POSSIBLE CIGS COULD SCATTER
OUT SOME. OVERALL LOW CONFIDNECE IN TIMING OF IMPROVEMENT FROM
MVFR.
IZZI
UPDATED 06Z...
BAND OF SNOW THAT IS MAINLY WEST OF CHICAGO...WILL CONTINUE TO
TRANSLATE SOUTH OVERNIGHT. STILL COULD BE SOME FLURRIES OR BRIEF
LIGHT SNOW AT THE CHICAGO AREA TERMINALS FOR THE FIRST FEW HOURS
OF THE TAF CYCLE...BUT SHOULD BE OF LITTLE SIGNIFICANCE AND HAVE
NO OPERATIONAL IMPACT. MVFR CIGS...POSSIBLY LAKE INDUCED...SHOULD
LINGER THROUGH THE OVERNIGHT AND POSSIBLY INTO SUNDAY MORNING
BEFORE CONDITIONS TREND VFR. STRONG/GUSTY NORTHEAST WINDS EXPECTED
TO LAST THROUGH THE DAY WITH A FEW GUSTS POSSIBLY NEARING 30KT
THROUGH SUNDAY MORNING. GUSTINESS AND THEN WINDS WILL DIMINISH
EARLY SUNDAY EVENING.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* LOW CONFIDENCE IN TIMING SCATTERING OUT OF LAKE EFFECT MVFR CIGS
* HIGH CONFIDENCE IN OTHER FORECAST ELEMENTS
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR.
TUESDAY...VFR. GUSTY SOUTH WINDS.
WEDNESDAY...SLIGHT CHANCE -SHRA.
THURSDAY THROUGH SATURDAY...GENERALLY VFR. SLIGHT CHANCE FOR LGT
SNOW THURSDAY NIGHT THROUGH SATURDAY MORNING.
BEACHLER
&&
.MARINE...
251 AM CDT
FAIRLY STRONG NORTHEAST WINDS TO JUST BELOW GALE FORCE THIS
MORNING OVER THE SOUTH THIRD OF THE LAKE SHOULD BEGIN TO EASE THIS
AFTERNOON AND ESPECIALLY TONIGHT AS HIGH PRESSURE INCHES CLOSER TO
REGION AND LOW PRESSURE TO OUR SOUTH SCOOTS OFF TO THE EAST.
SOUTHEASTERLY WINDS SHOULD DEVELOP AND GRADUALLY FRESHEN UP MONDAY
NIGHT THROUGH TUESDAY NIGHT IN ADVANCE OF THE NEXT LOW. FAIRLY
STRONG LOW AND FORMIDABLE SHOT OF COLD AIR BEHIND IT COULD ALLOW
FOR A PERIOD OF WESTERLY GALES WEDNESDAY BEFORE WINDS SLACKEN A
BIT LATE IN THE WEEK.
IZZI
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 9 PM SUNDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
330 AM CDT Sun Mar 16 2014
.DISCUSSION...
ISSUED 330 AM CDT Sun Mar 16 2014
SHORT TERM...Today through Thursday
00Z models continue to trend further south with surface low
pressure and associated qpf fields over southern areas today.
Therefore continue to lower pops and qpf/snowfall amounts over
southern counties today. A light snow band nw of the IL river has
produced between a half to 1 inch the past several hours from Knox,
Stark and Marshall counties nw toward the Quad Cities. RUC/HRRR
models diminish this light snow band over the IL river valley
through mid morning/15Z and any additional snow accumulations
should be less than 1 inch as it weakens.
1003 mb low pressure over west central AR while 1037 mb high
pressure was near the MN/Canadian border. Very tight pressure
gradient over IL between these systems giving gusty ne winds as
high as 35 to 43 mph over central IL early this morning. RUC and
NAM models show these higher wind gusts of 35-45 mph shifting
ssw by midday so strongest winds over central IL during the
morning and not quite as strong in the afternoon hours. Still
think shy of wind advisory criteria though a few spots could reach
sustained around 30 mph or a bit higher and/or wind gusts near 45
mph. Low pressure to track east across northern MS/AL today and
keep brunt of heavier pcpn south of IL. Have chance of mixed
precip this morning southern areas and mainly just chance of light
snow se IL this afternoon and ending by late today as low pressure
system pulls away from IL.
Much colder today and little temperature rise and se IL may even
see temps slipping during the day into the lower 30s. Clouds
decreasing over the IL river valley this afternoon and over rest
of area during the evening with diminishing winds. Cold lows in
the mid to upper teens tonight with southeast IL around 20F.
Nice warmup in store Mon and especially Tue with upper 50s and
lower 60s possible Tue afternoon. 995 mb low pressure passes nw of
IL Tue night and brings a cold front east through the state with
chance of rain showers and diminishing already during Wed. Temps
cool just a bit behind this system Wed/Thu but still could see
highs in upper 40s to mid 50s.
LONG TERM...Thursday night through Sunday
Milder temps return Friday with breezy southerly winds and highs
back into the upper 50s and lower 60s with even mid 60s se of I-70.
Low pressure passes to north of central IL again Fri/Fri night
brining a cold front through Friday night and next chance of rain
showers Fri and Fri night. Canadian high pressure building down
into the Midwest this weekend to bring colder temperatures back to
the region.
07
&&
.AVIATION...
ISSUED 1153 PM CDT Sat Mar 15 2014
A band of light snow will drop into northern parts of the area
just after midnight and begin to affect PIA and BMI. Cigs will
drop into MVFR category with Vis around 3-4sm. The light snow will
continue into the early morning hours at both sites, but not get
any worse. After the snow ends, cigs will rise and then continue
to rise into the afternoon hours and then skies will completely
clear during the evening hours. A different scenario will occur at
the other sites. SPI will not see any snow at the site until close
to morning, and the system will have become weaker. So vis will
only get down to 5sm with cigs around 3kft. Like PIA and BMI cigs
will improve once the snow ends around noon, and then eventually
clear during the evening hours. DEC and CMI will likely not see
any snow, but since clouds could get down to around 5kft during
the morning, will have just VCSH in forecast. Like the rest the
cloud heights will rise during the afternoon and then eventually
clear during the evening. Winds will be northeast through the
period. Winds speeds will be gusty and then increase during the
overnight hours and continue through the day, since the system
will be strengthening some to the south of the area. Expecting
gusts as high as 30-35kts through the period and most sites.
During the evening, winds will decrease but still remain around
14kts, but not gusts.
Auten
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1249 PM CDT SUN MAR 16 2014
.UPDATE...
ISSUED AT 1034 AM CDT SUN MAR 16 2014
AREAL FLOOD WATCH ALONG THE ROCK RIVER FOR THE POTENTIAL OF ICE
JAMS/ICE ACTION INDUCED FLOODING EXTENDED THROUGH MON EVENING/00Z
TUE. AS FOR THE FORECAST...STRONG LOW TO MID LEVEL NORTHEAST FLOW
WRAPPING AROUND NORTH SIDE OF AR CYCLONE INDUCING CU ROW FIELDS
OFF LK MICHIGAN. EVEN SOME FLURRIES GETTING WRUNG OUT OF THIS
ACTIVITY...SOME OF WHICH IS MAKING IT FAR ENOUGH TO THE WEST AND
SOUTHWEST TO GET INTO THE NORTHEASTERN THIRD OR MORE OF THE DVN CWA.
THUS HAVE INCREASE CLOUD COVER IN THOSE AREAS WITH A MENTION OF
FLURRIES. THESE CLOUDS MAY ALSO HAMPER WARM UP POTENTIAL IN THE
EASTERN AND NORTHEASTERN FCST AREA...IF THEY LAST THROUGH LATE
AFTERNOON. DEEPENING SUBSIDENCE SHOULD INCREASE FROM THE WEST AS
THE AFTERNOON PROGRESSES AND WILL BE INTERESTING TO SEE WHAT
EFFECT IT HAS ON THESE CU ROWS AND FLURRIES. THUS MAYBE SOME
DECREASE IN THE CLOUDS BY LATE AFTERNOON. ..12..
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 219 AM CDT SUN MAR 16 2014
FORECAST FOCUS ON SNOW CHANCES THIS MORNING THEN ON CLOUD TRENDS
THROUGH THE DAY.
SNOW TO CONTINUE TO SHIFT SOUTH AND EAST THIS MORNING OVER THE
SOUTHERN HALF OF THE CWA. LATEST RAP TRENDS AND TIME HEIGHT
SECTIONS SHOW FORCING WEAKENING AS THE MORNING PROGRESSES WITH
SNOW DISSIPATING AND EXITING THE FAR SOUTH BY LATE MORNING.
ADDITIONAL SNOW ACCUMS AROUND AN INCH EXPECTED SOUTH OF I-80 WITH
A FEW AMOUNTS UP TO TWO INCHES NOT OUT OF THE QUESTION IN THE
HEAVIEST SNOW BANDS. TEMPERATURES IN THE SOUTH ARE CURRENTLY AT OR
SLIGHTLY ABOVE FREEZING SO ANTICIPATE SNOW TO ACCUMULATE MAINLY ON
ELEVATED AND GRASSY SURFACES IN THESE AREAS. AFTER THE SNOW
ENDS...COLD AND BRISK CONDITIONS WILL BE SEEN AS BREEZY NORTHEAST WINDS
ALONG WITH CAA IN THE LOW LEVELS OF THE ATMOSPHERE TO KEEP
TEMPERATURES BELOW NORMAL. HOWEVER...INCREASING SUBSIDENCE BEHIND
SHORTWAVE TO ALLOW FOR CLOUDS TO CLEAR FROM NORTH TO SOUTH WITH
MOST OF THE CWA SEEING MOSTLY SUNNY SKIES BY NOON AS HIGH PRESSURE
SHIFTS EAST OVER THE GREAT LAKES REGION. THE STRENGTHENING MID-
MARCH SUN SHOULD BOOST TEMPERATURES A CATEGORY OR TWO ABOVE MODEL
GUIDANCE THUS WILL GO WITH HIGHS IN THE UPPER 20S TO LOW 30S
TODAY. THIS IS ABOUT 15 TO 20 DEGREES BELOW NORMAL FOR MID MARCH.
TONIGHT...QUIET AND COLD CONDITIONS EXPECTED AS HIGH PRESSURE
MOVES EAST INTO MICHIGAN. CLEAR SKIES AND LIGHT WINDS OUT OF THE EAST TO
PUSH TEMPERATURES INTO THE TEENS BY MONDAY MORNING. IF ANY SNOW
REMAINS FROM THIS MORNING/S EVENT THEN TEMPERATURES MAY NEED TO BE
LOWERED A FEW DEGREES IN THOSE AREAS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 219 AM CDT SUN MAR 16 2014
MONDAY AND TUESDAY BOTH CONTINUE TO APPEAR AT TWO DAYS OF CONTINUAL
WARM ADVECTION...LARGELY WITHOUT MUCH MOISTURE. THUS...A SOUTH
BREEZE OF 15 TO 20 MPH FROM MONDAY THROUGH TUESDAY IS
FORECAST...WITH A GRADUAL INCREASE IN MID AND HIGH CLOUDS ARRIVING
TUESDAY. WE MAY NEED TO MELT OFF SOME SNOW ON MONDAY ....BUT GIVEN
SOME SUN TODAY AND MONDAY...IT SHOULD BE EASILY MELTED OFF BY MID
MORNING...WITH MODEST HIGHS IN THE MID 30S NORTHEAST TO MID 40S
SOUTHWEST FORECAST. MONDAY NIGHT...A BRIEF FALL BELOW FREEZING
SHOULD OCCUR IN MOST LOCATIONS EXCEPT THE SOUTHWEST...BEFORE
TEMPERATURES RISE LATE. THIS WILL SET THE STAGE FOR A BREEZY AND
MILD TUESDAY...AHEAD OF THE FAST MOVING STORM TUESDAY NIGHT. THE
GFS/NAM/UKMET ALL TAKE THE ENERGY AND LOW WELL NORTH OF THE CWA
TUESDAY NIGHT...WHILE THE ECMWF AND GEM KEEP A STRONGER SOUTHERLY
TRACK OVER OUR CWA. THE ECMWF HAS BEEN THE MOST CONSISTENT MODEL
SHOWING THIS...AND CANNOT BE RULED OUT YET. STILL...A DRY TUESDAY
LOOKS MOST LIKELY...GIVEN THE WEAK MOISTURE RETURN IN THE WAA.
BEHIND THE SYSTEM...IN EITHER POST FRONTAL SHOWERS...OR THROUGH A
SOUTHERN TRACKING ECMWF DEFORMATION ZONE...WE SHOULD GET OUT MAIN
PCPN THREAT. THIS LOOKS TO BE FROM TUESDAY NIGHT INTO EARLY
WEDNESDAY MORNING. AS WE GO THROUGH WEDNESDAY...WINDS WILL BE WEST
AND STILL QUITE BREEZY...AT LEAST 15 MPH IF NOT 20 MPH SUSTAINED
WITH GUST LIKELY OVER 30 MPH.
THURSDAY THROUGH LATE WEEK...MODELS LOOSE CONSISTENCY AS THEY HAVE
FOR SEVERAL DAYS NOW. THE ECMWF AND GFS BOTH HAVE SEVERAL PASSING
WEAKER SYSTEMS...THE MOST SIGNIFICANT IF WHICH RELATES TO FRIDAY. A
CHANCE FOR RAIN IS INCLUDED FOR THURSDAY NIGHT THROUGH FRIDAY FOR
THIS...ALMOST CLIPPER LIKE SYSTEM. GIVEN THAT IT IS MARCH...AND WE
SHOULD NOT HAVE SNOW COVER TO DEAL WITH MID TO LATE WEEK...THESE
SYSTEMS SHOULD BE ABLE TO PRODUCE A SUBSTANTIAL WARM UP AHEAD OF
THEM...LIKELY INTO THE 50S TO LOWER 60S. TIMING OF THEM WILL BE VERY
HARD...IF NOT IMPOSSIBLE THIS FAR OUT LEADING TO A MUCH HIGHER THAN
NORMAL PROBABILITY OF TEMPERATURE FORECAST BUSTS.
ERVIN
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1239 PM CDT SUN MAR 16 2014
MVFR CIGS HANGING ON IN THE VCNTY OF MLI AND BRL THROUGH AT LEAST
MID AFTERNOON BEFORE SOME DECREASE EXPECTED AS SUBSIDENCE TAKES
HOLD FROM THE WEST. SOME OF THESE CLOUDS OF LK EFFECT ORIGIN IN
BRISK LLVL NORTHEAST FLOW ON NORTH SIDE OF AR-TN VALLEY CYCLONE.
AS FLOW BECOMES MORE NORTHERLY THIS EVENING ALSO LOSS OF FETCH
AND HEATING TO HELP LOWER CLOUDS TO DIMINISH. RIDE OVERHEAD AND
LIGHT EAST WINDS OVERNIGHT...WILL HAVE TO WATCH FOR AT LEAST SOME
MVFR FOG TOWARD MORNING UNDER THESE CONDITIONS ESPECIALLY AT BRL
WITH FRESH SNOW COVER AND SOME MELT INTO SFC LAYER. SOUTHEAST
WINDS TO INCREASE BY MID TO LATE MON MORNING AHEAD OF NEXT SYSTEM
ACRS THE NORTHERN PLAINS. ..12..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...FLOOD WATCH THROUGH MONDAY EVENING FOR HENRY IL-ROCK ISLAND-
WHITESIDE.
MO...NONE.
&&
$$
UPDATE...12
SYNOPSIS...GROSS
SHORT TERM...GROSS
LONG TERM...ERVIN
AVIATION...12
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1043 AM CDT SUN MAR 16 2014
.UPDATE...
ISSUED AT 1034 AM CDT SUN MAR 16 2014
AREAL FLOOD WATCH ALONG THE ROCK RIVER FOR THE POTENTIAL OF ICE
JAMS/ICE ACTION INDUCED FLOODING EXTENDED THROUGH MON EVENING/00Z
TUE. AS FOR THE FORECAST...STRONG LOW TO MID LEVEL NORTHEAST FLOW
WRAPPING AROUND NORTH SIDE OF AR CYCLONE INDUCING CU ROW FIELDS
OFF LK MICHIGAN. EVEN SOME FLURRIES GETTING WRUNG OUT OF THIS
ACTIVITY...SOME OF WHICH IS MAKING IT FAR ENOUGH TO THE WEST AND
SOUTHWEST TO GET INTO THE NORTHEASTERN THIRD OR MORE OF THE DVN CWA.
THUS HAVE INCREASE CLOUD COVER IN THOSE AREAS WITH A MENTION OF
FLURRIES. THESE CLOUDS MAY ALSO HAMPER WARM UP POTENTIAL IN THE
EASTERN AND NORTHEASTERN FCST AREA...IF THEY LAST THROUGH LATE
AFTERNOON. DEEPENING SUBSIDENCE SHOULD INCREASE FROM THE WEST AS
THE AFTERNOON PROGRESSES AND WILL BE INTERESTING TO SEE WHAT
EFFECT IT HAS ON THESE CU ROWS AND FLURRIES. THUS MAYBE SOME
DECREASE IN THE CLOUDS BY LATE AFTERNOON. ..12..
&&
.SYNOPSIS...
ISSUED AT 219 AM CDT SUN MAR 16 2014
06Z SURFACE ANALYSIS SHOWED SURFACE LOW IMPACTING THE LOCAL AREA
DIVING SOUTHEAST OVER WEST CENTRAL MISSOURI WITH A STRONGER LOW
ALONG THE OKLAHOMA-ARKANSAS BORDER. IMPRESSIVE PRESSURE RISES
NOTED BEHIND THE TWO SYSTEMS STRETCHING FROM WESTERN OKLAHOMA INTO
NORTHEAST KANSAS. LOW LEVEL THERMAL GRADIENT ALSO EVIDENT
EXTENDING EAST FROM THE WEST CENTRAL MISSOURI LOW. LATEST RADAR
IMAGERY SHOWED THAT THE TWO FGEN BANDS OF SNOW THAT WERE ALONG
I-80 AND ALONG A LINE FROM CENTERVILLE IOWA TO WASHINGTON AROUND
MIDNIGHT HAVE MERGED INTO ONE MAIN BAND OF SNOW STRETCHING FROM
CENTERVILLE IOWA THROUGH THE QUAD CITIES AT 0730Z. VISIBILITIES
HAVE BEEN REDUCED DOWN TO A THREE QUARTERS OF A MILE AT TIMES WITH
A HALF INCH OF SNOW RECORDED AT THE NWS OFFICE IN DAVENPORT AT
06Z. AT 2AM...TEMPERATURES WERE IN THE UPPER 20S NORTH TO LOWER
30S SOUTH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 219 AM CDT SUN MAR 16 2014
FORECAST FOCUS ON SNOW CHANCES THIS MORNING THEN ON CLOUD TRENDS
THROUGH THE DAY.
SNOW TO CONTINUE TO SHIFT SOUTH AND EAST THIS MORNING OVER THE
SOUTHERN HALF OF THE CWA. LATEST RAP TRENDS AND TIME HEIGHT
SECTIONS SHOW FORCING WEAKENING AS THE MORNING PROGRESSES WITH
SNOW DISSIPATING AND EXITING THE FAR SOUTH BY LATE MORNING.
ADDITIONAL SNOW ACCUMS AROUND AN INCH EXPECTED SOUTH OF I-80 WITH
A FEW AMOUNTS UP TO TWO INCHES NOT OUT OF THE QUESTION IN THE
HEAVIEST SNOW BANDS. TEMPERATURES IN THE SOUTH ARE CURRENTLY AT OR
SLIGHTLY ABOVE FREEZING SO ANTICIPATE SNOW TO ACCUMULATE MAINLY ON
ELEVATED AND GRASSY SURFACES IN THESE AREAS. AFTER THE SNOW
ENDS...COLD AND BRISK CONDITIONS WILL BE SEEN AS BREEZY NORTHEAST WINDS
ALONG WITH CAA IN THE LOW LEVELS OF THE ATMOSPHERE TO KEEP
TEMPERATURES BELOW NORMAL. HOWEVER...INCREASING SUBSIDENCE BEHIND
SHORTWAVE TO ALLOW FOR CLOUDS TO CLEAR FROM NORTH TO SOUTH WITH
MOST OF THE CWA SEEING MOSTLY SUNNY SKIES BY NOON AS HIGH PRESSURE
SHIFTS EAST OVER THE GREAT LAKES REGION. THE STRENGTHENING MID-
MARCH SUN SHOULD BOOST TEMPERATURES A CATEGORY OR TWO ABOVE MODEL
GUIDANCE THUS WILL GO WITH HIGHS IN THE UPPER 20S TO LOW 30S
TODAY. THIS IS ABOUT 15 TO 20 DEGREES BELOW NORMAL FOR MID MARCH.
TONIGHT...QUIET AND COLD CONDITIONS EXPECTED AS HIGH PRESSURE
MOVES EAST INTO MICHIGAN. CLEAR SKIES AND LIGHT WINDS OUT OF THE EAST TO
PUSH TEMPERATURES INTO THE TEENS BY MONDAY MORNING. IF ANY SNOW
REMAINS FROM THIS MORNING/S EVENT THEN TEMPERATURES MAY NEED TO BE
LOWERED A FEW DEGREES IN THOSE AREAS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 219 AM CDT SUN MAR 16 2014
MONDAY AND TUESDAY BOTH CONTINUE TO APPEAR AT TWO DAYS OF CONTINUAL
WARM ADVECTION...LARGELY WITHOUT MUCH MOISTURE. THUS...A SOUTH
BREEZE OF 15 TO 20 MPH FROM MONDAY THROUGH TUESDAY IS
FORECAST...WITH A GRADUAL INCREASE IN MID AND HIGH CLOUDS ARRIVING
TUESDAY. WE MAY NEED TO MELT OFF SOME SNOW ON MONDAY ....BUT GIVEN
SOME SUN TODAY AND MONDAY...IT SHOULD BE EASILY MELTED OFF BY MID
MORNING...WITH MODEST HIGHS IN THE MID 30S NORTHEAST TO MID 40S
SOUTHWEST FORECAST. MONDAY NIGHT...A BRIEF FALL BELOW FREEZING
SHOULD OCCUR IN MOST LOCATIONS EXCEPT THE SOUTHWEST...BEFORE
TEMPERATURES RISE LATE. THIS WILL SET THE STAGE FOR A BREEZY AND
MILD TUESDAY...AHEAD OF THE FAST MOVING STORM TUESDAY NIGHT. THE
GFS/NAM/UKMET ALL TAKE THE ENERGY AND LOW WELL NORTH OF THE CWA
TUESDAY NIGHT...WHILE THE ECMWF AND GEM KEEP A STRONGER SOUTHERLY
TRACK OVER OUR CWA. THE ECMWF HAS BEEN THE MOST CONSISTENT MODEL
SHOWING THIS...AND CANNOT BE RULED OUT YET. STILL...A DRY TUESDAY
LOOKS MOST LIKELY...GIVEN THE WEAK MOISTURE RETURN IN THE WAA.
BEHIND THE SYSTEM...IN EITHER POST FRONTAL SHOWERS...OR THROUGH A
SOUTHERN TRACKING ECMWF DEFORMATION ZONE...WE SHOULD GET OUT MAIN
PCPN THREAT. THIS LOOKS TO BE FROM TUESDAY NIGHT INTO EARLY
WEDNESDAY MORNING. AS WE GO THROUGH WEDNESDAY...WINDS WILL BE WEST
AND STILL QUITE BREEZY...AT LEAST 15 MPH IF NOT 20 MPH SUSTAINED
WITH GUST LIKELY OVER 30 MPH.
THURSDAY THROUGH LATE WEEK...MODELS LOOSE CONSISTENCY AS THEY HAVE
FOR SEVERAL DAYS NOW. THE ECMWF AND GFS BOTH HAVE SEVERAL PASSING
WEAKER SYSTEMS...THE MOST SIGNIFICANT IF WHICH RELATES TO FRIDAY. A
CHANCE FOR RAIN IS INCLUDED FOR THURSDAY NIGHT THROUGH FRIDAY FOR
THIS...ALMOST CLIPPER LIKE SYSTEM. GIVEN THAT IT IS MARCH...AND WE
SHOULD NOT HAVE SNOW COVER TO DEAL WITH MID TO LATE WEEK...THESE
SYSTEMS SHOULD BE ABLE TO PRODUCE A SUBSTANTIAL WARM UP AHEAD OF
THEM...LIKELY INTO THE 50S TO LOWER 60S. TIMING OF THEM WILL BE VERY
HARD...IF NOT IMPOSSIBLE THIS FAR OUT LEADING TO A MUCH HIGHER THAN
NORMAL PROBABILITY OF TEMPERATURE FORECAST BUSTS.
ERVIN
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 640 AM CDT SUN MAR 16 2014
LIFR CONDITIONS IN SNOW TO COME TO AN END AT THE BRL TERMINAL
WITHIN THE NEXT HOUR AS THE SYSTEM EXITS TO THE SOUTHEAST.
OTHERWISE MVFR CIGS WILL BE FOUND AT ALL TAF SITES BEFORE GRADUAL
CLEARING TAKES FROM NORTH TO SOUTH IN THE AFTERNOON GIVING WAY TO
VFR CONDITIONS. NORTHEAST WINDS BETWEEN 15 AND 20 KTS EXPECTED IN THE
MORNING WITH OCCASIONAL GUSTS AOA 25 KTS POSSIBLE. WINDS TO
DIMINISH BELOW 10 KTS BY LATE AFTERNOON/EARLY EVENING WITH CLEAR
TO MOSTLY CLEAR SKIES.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...FLOOD WATCH THROUGH MONDAY EVENING FOR HENRY IL-ROCK ISLAND-
WHITESIDE.
MO...NONE.
&&
$$
UPDATE...12
SYNOPSIS...GROSS
SHORT TERM...GROSS
LONG TERM...ERVIN
AVIATION...GROSS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
654 AM CDT SUN MAR 16 2014
.SYNOPSIS...
ISSUED AT 219 AM CDT SUN MAR 16 2014
06Z SURFACE ANALYSIS SHOWED SURFACE LOW IMPACTING THE LOCAL AREA
DIVING SOUTHEAST OVER WEST CENTRAL MISSOURI WITH A STRONGER LOW
ALONG THE OKLAHOMA-ARKANSAS BORDER. IMPRESSIVE PRESSURE RISES
NOTED BEHIND THE TWO SYSTEMS STRETCHING FROM WESTERN OKLAHOMA INTO
NORTHEAST KANSAS. LOW LEVEL THERMAL GRADIENT ALSO EVIDENT
EXTENDING EAST FROM THE WEST CENTRAL MISSOURI LOW. LATEST RADAR
IMAGERY SHOWED THAT THE TWO FGEN BANDS OF SNOW THAT WERE ALONG
I-80 AND ALONG A LINE FROM CENTERVILLE IOWA TO WASHINGTON AROUND
MIDNIGHT HAVE MERGED INTO ONE MAIN BAND OF SNOW STRETCHING FROM
CENTERVILLE IOWA THROUGH THE QUAD CITIES AT 0730Z. VISIBILITIES
HAVE BEEN REDUCED DOWN TO A THREE QUARTERS OF A MILE AT TIMES WITH
A HALF INCH OF SNOW RECORDED AT THE NWS OFFICE IN DAVENPORT AT
06Z. AT 2AM...TEMPERATURES WERE IN THE UPPER 20S NORTH TO LOWER
30S SOUTH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 219 AM CDT SUN MAR 16 2014
FORECAST FOCUS ON SNOW CHANCES THIS MORNING THEN ON CLOUD TRENDS
THROUGH THE DAY.
SNOW TO CONTINUE TO SHIFT SOUTH AND EAST THIS MORNING OVER THE
SOUTHERN HALF OF THE CWA. LATEST RAP TRENDS AND TIME HEIGHT
SECTIONS SHOW FORCING WEAKENING AS THE MORNING PROGRESSES WITH
SNOW DISSIPATING AND EXITING THE FAR SOUTH BY LATE MORNING.
ADDITIONAL SNOW ACCUMS AROUND AN INCH EXPECTED SOUTH OF I-80 WITH
A FEW AMOUNTS UP TO TWO INCHES NOT OUT OF THE QUESTION IN THE
HEAVIEST SNOW BANDS. TEMPERATURES IN THE SOUTH ARE CURRENTLY AT OR
SLIGHTLY ABOVE FREEZING SO ANTICIPATE SNOW TO ACCUMULATE MAINLY ON
ELEVATED AND GRASSY SURFACES IN THESE AREAS. AFTER THE SNOW
ENDS...COLD AND BRISK CONDITIONS WILL BE SEEN AS BREEZY NORTHEAST WINDS
ALONG WITH CAA IN THE LOW LEVELS OF THE ATMOSPHERE TO KEEP
TEMPERATURES BELOW NORMAL. HOWEVER...INCREASING SUBSIDENCE BEHIND
SHORTWAVE TO ALLOW FOR CLOUDS TO CLEAR FROM NORTH TO SOUTH WITH
MOST OF THE CWA SEEING MOSTLY SUNNY SKIES BY NOON AS HIGH PRESSURE
SHIFTS EAST OVER THE GREAT LAKES REGION. THE STRENGTHENING MID-
MARCH SUN SHOULD BOOST TEMPERATURES A CATEGORY OR TWO ABOVE MODEL
GUIDANCE THUS WILL GO WITH HIGHS IN THE UPPER 20S TO LOW 30S
TODAY. THIS IS ABOUT 15 TO 20 DEGREES BELOW NORMAL FOR MID MARCH.
TONIGHT...QUIET AND COLD CONDITIONS EXPECTED AS HIGH PRESSURE
MOVES EAST INTO MICHIGAN. CLEAR SKIES AND LIGHT WINDS OUT OF THE EAST TO
PUSH TEMPERATURES INTO THE TEENS BY MONDAY MORNING. IF ANY SNOW
REMAINS FROM THIS MORNING/S EVENT THEN TEMPERATURES MAY NEED TO BE
LOWERED A FEW DEGREES IN THOSE AREAS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 219 AM CDT SUN MAR 16 2014
MONDAY AND TUESDAY BOTH CONTINUE TO APPEAR AT TWO DAYS OF CONTINUAL
WARM ADVECTION...LARGELY WITHOUT MUCH MOISTURE. THUS...A SOUTH
BREEZE OF 15 TO 20 MPH FROM MONDAY THROUGH TUESDAY IS
FORECAST...WITH A GRADUAL INCREASE IN MID AND HIGH CLOUDS ARRIVING
TUESDAY. WE MAY NEED TO MELT OFF SOME SNOW ON MONDAY ....BUT GIVEN
SOME SUN TODAY AND MONDAY...IT SHOULD BE EASILY MELTED OFF BY MID
MORNING...WITH MODEST HIGHS IN THE MID 30S NORTHEAST TO MID 40S
SOUTHWEST FORECAST. MONDAY NIGHT...A BRIEF FALL BELOW FREEZING
SHOULD OCCUR IN MOST LOCATIONS EXCEPT THE SOUTHWEST...BEFORE
TEMPERATURES RISE LATE. THIS WILL SET THE STAGE FOR A BREEZY AND
MILD TUESDAY...AHEAD OF THE FAST MOVING STORM TUESDAY NIGHT. THE
GFS/NAM/UKMET ALL TAKE THE ENERGY AND LOW WELL NORTH OF THE CWA
TUESDAY NIGHT...WHILE THE ECMWF AND GEM KEEP A STRONGER SOUTHERLY
TRACK OVER OUR CWA. THE ECMWF HAS BEEN THE MOST CONSISTENT MODEL
SHOWING THIS...AND CANNOT BE RULED OUT YET. STILL...A DRY TUESDAY
LOOKS MOST LIKELY...GIVEN THE WEAK MOISTURE RETURN IN THE WAA.
BEHIND THE SYSTEM...IN EITHER POST FRONTAL SHOWERS...OR THROUGH A
SOUTHERN TRACKING ECMWF DEFORMATION ZONE...WE SHOULD GET OUT MAIN
PCPN THREAT. THIS LOOKS TO BE FROM TUESDAY NIGHT INTO EARLY
WEDNESDAY MORNING. AS WE GO THROUGH WEDNESDAY...WINDS WILL BE WEST
AND STILL QUITE BREEZY...AT LEAST 15 MPH IF NOT 20 MPH SUSTAINED
WITH GUST LIKELY OVER 30 MPH.
THURSDAY THROUGH LATE WEEK...MODELS LOOSE CONSISTENCY AS THEY HAVE
FOR SEVERAL DAYS NOW. THE ECMWF AND GFS BOTH HAVE SEVERAL PASSING
WEAKER SYSTEMS...THE MOST SIGNIFICANT IF WHICH RELATES TO FRIDAY. A
CHANCE FOR RAIN IS INCLUDED FOR THURSDAY NIGHT THROUGH FRIDAY FOR
THIS...ALMOST CLIPPER LIKE SYSTEM. GIVEN THAT IT IS MARCH...AND WE
SHOULD NOT HAVE SNOW COVER TO DEAL WITH MID TO LATE WEEK...THESE
SYSTEMS SHOULD BE ABLE TO PRODUCE A SUBSTANTIAL WARM UP AHEAD OF
THEM...LIKELY INTO THE 50S TO LOWER 60S. TIMING OF THEM WILL BE VERY
HARD...IF NOT IMPOSSIBLE THIS FAR OUT LEADING TO A MUCH HIGHER THAN
NORMAL PROBABILITY OF TEMPERATURE FORECAST BUSTS.
ERVIN
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 640 AM CDT SUN MAR 16 2014
LIFR CONDITIONS IN SNOW TO COME TO AN END AT THE BRL TERMINAL
WITHIN THE NEXT HOUR AS THE SYSTEM EXITS TO THE SOUTHEAST.
OTHERWISE MVFR CIGS WILL BE FOUND AT ALL TAF SITES BEFORE GRADUAL
CLEARING TAKES FROM NORTH TO SOUTH IN THE AFTERNOON GIVING WAY TO
VFR CONDITIONS. NORTHEAST WINDS BETWEEN 15 AND 20 KTS EXPECTED IN THE
MORNING WITH OCCASIONAL GUSTS AOA 25 KTS POSSIBLE. WINDS TO
DIMINISH BELOW 10 KTS BY LATE AFTERNOON/EARLY EVENING WITH CLEAR
TO MOSTLY CLEAR SKIES.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...FLOOD WATCH THROUGH THIS EVENING FOR HENRY IL-ROCK ISLAND-
WHITESIDE.
MO...NONE.
&&
$$
SYNOPSIS...GROSS
SHORT TERM...GROSS
LONG TERM...ERVIN
AVIATION...GROSS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
307 AM CDT SUN MAR 16 2014
.SYNOPSIS...
ISSUED AT 219 AM CDT SUN MAR 16 2014
06Z SURFACE ANALYSIS SHOWED SURFACE LOW IMPACTING THE LOCAL AREA
DIVING SOUTHEAST OVER WEST CENTRAL MISSOURI WITH A STRONGER LOW
ALONG THE OKLAHOMA-ARKANSAS BORDER. IMPRESSIVE PRESSURE RISES
NOTED BEHIND THE TWO SYSTEMS STRETCHING FROM WESTERN OKLAHOMA INTO
NORTHEAST KANSAS. LOW LEVEL THERMAL GRADIENT ALSO EVIDENT
EXTENDING EAST FROM THE WEST CENTRAL MISSOURI LOW. LATEST RADAR
IMAGERY SHOWED THAT THE TWO FGEN BANDS OF SNOW THAT WERE ALONG
I-80 AND ALONG A LINE FROM CENTERVILLE IOWA TO WASHINGTON AROUND
MIDNIGHT HAVE MERGED INTO ONE MAIN BAND OF SNOW STRETCHING FROM
CENTERVILLE IOWA THROUGH THE QUAD CITIES AT 0730Z. VISIBILITIES
HAVE BEEN REDUCED DOWN TO A THREE QUARTERS OF A MILE AT TIMES WITH
A HALF INCH OF SNOW RECORDED AT THE NWS OFFICE IN DAVENPORT AT
06Z. AT 2AM...TEMPERATURES WERE IN THE UPPER 20S NORTH TO LOWER
30S SOUTH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 219 AM CDT SUN MAR 16 2014
FORECAST FOCUS ON SNOW CHANCES THIS MORNING THEN ON CLOUD TRENDS
THROUGH THE DAY.
SNOW TO CONTINUE TO SHIFT SOUTH AND EAST THIS MORNING OVER THE
SOUTHERN HALF OF THE CWA. LATEST RAP TRENDS AND TIME HEIGHT
SECTIONS SHOW FORCING WEAKENING AS THE MORNING PROGRESSES WITH
SNOW DISSIPATING AND EXITING THE FAR SOUTH BY LATE MORNING.
ADDITIONAL SNOW ACCUMS AROUND AN INCH EXPECTED SOUTH OF I-80 WITH
A FEW AMOUNTS UP TO TWO INCHES NOT OUT OF THE QUESTION IN THE
HEAVIEST SNOW BANDS. TEMPERATURES IN THE SOUTH ARE CURRENTLY AT OR
SLIGHTLY ABOVE FREEZING SO ANTICIPATE SNOW TO ACCUMULATE MAINLY ON
ELEVATED AND GRASSY SURFACES IN THESE AREAS. AFTER THE SNOW
ENDS...COLD AND BRISK CONDITIONS WILL BE SEEN AS BREEZY NORTHEAST WINDS
ALONG WITH CAA IN THE LOW LEVELS OF THE ATMOSPHERE TO KEEP
TEMPERATURES BELOW NORMAL. HOWEVER...INCREASING SUBSIDENCE BEHIND
SHORTWAVE TO ALLOW FOR CLOUDS TO CLEAR FROM NORTH TO SOUTH WITH
MOST OF THE CWA SEEING MOSTLY SUNNY SKIES BY NOON AS HIGH PRESSURE
SHIFTS EAST OVER THE GREAT LAKES REGION. THE STRENGTHENING MID-
MARCH SUN SHOULD BOOST TEMPERATURES A CATEGORY OR TWO ABOVE MODEL
GUIDANCE THUS WILL GO WITH HIGHS IN THE UPPER 20S TO LOW 30S
TODAY. THIS IS ABOUT 15 TO 20 DEGREES BELOW NORMAL FOR MID MARCH.
TONIGHT...QUIET AND COLD CONDITIONS EXPECTED AS HIGH PRESSURE
MOVES EAST INTO MICHIGAN. CLEAR SKIES AND LIGHT WINDS OUT OF THE EAST TO
PUSH TEMPERATURES INTO THE TEENS BY MONDAY MORNING. IF ANY SNOW
REMAINS FROM THIS MORNING/S EVENT THEN TEMPERATURES MAY NEED TO BE
LOWERED A FEW DEGREES IN THOSE AREAS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 219 AM CDT SUN MAR 16 2014
MONDAY AND TUESDAY BOTH CONTINUE TO APPEAR AT TWO DAYS OF CONTINUAL
WARM ADVECTION...LARGELY WITHOUT MUCH MOISTURE. THUS...A SOUTH
BREEZE OF 15 TO 20 MPH FROM MONDAY THROUGH TUESDAY IS
FORECAST...WITH A GRADUAL INCREASE IN MID AND HIGH CLOUDS ARRIVING
TUESDAY. WE MAY NEED TO MELT OFF SOME SNOW ON MONDAY ....BUT GIVEN
SOME SUN TODAY AND MONDAY...IT SHOULD BE EASILY MELTED OFF BY MID
MORNING...WITH MODEST HIGHS IN THE MID 30S NORTHEAST TO MID 40S
SOUTHWEST FORECAST. MONDAY NIGHT...A BRIEF FALL BELOW FREEZING
SHOULD OCCUR IN MOST LOCATIONS EXCEPT THE SOUTHWEST...BEFORE
TEMPERATURES RISE LATE. THIS WILL SET THE STAGE FOR A BREEZY AND
MILD TUESDAY...AHEAD OF THE FAST MOVING STORM TUESDAY NIGHT. THE
GFS/NAM/UKMET ALL TAKE THE ENERGY AND LOW WELL NORTH OF THE CWA
TUESDAY NIGHT...WHILE THE ECMWF AND GEM KEEP A STRONGER SOUTHERLY
TRACK OVER OUR CWA. THE ECMWF HAS BEEN THE MOST CONSISTENT MODEL
SHOWING THIS...AND CANNOT BE RULED OUT YET. STILL...A DRY TUESDAY
LOOKS MOST LIKELY...GIVEN THE WEAK MOISTURE RETURN IN THE WAA.
BEHIND THE SYSTEM...IN EITHER POST FRONTAL SHOWERS...OR THROUGH A
SOUTHERN TRACKING ECMWF DEFORMATION ZONE...WE SHOULD GET OUT MAIN
PCPN THREAT. THIS LOOKS TO BE FROM TUESDAY NIGHT INTO EARLY
WEDNESDAY MORNING. AS WE GO THROUGH WEDNESDAY...WINDS WILL BE WEST
AND STILL QUITE BREEZY...AT LEAST 15 MPH IF NOT 20 MPH SUSTAINED
WITH GUST LIKELY OVER 30 MPH.
THURSDAY THROUGH LATE WEEK...MODELS LOOSE CONSISTENCY AS THEY HAVE
FOR SEVERAL DAYS NOW. THE ECMWF AND GFS BOTH HAVE SEVERAL PASSING
WEAKER SYSTEMS...THE MOST SIGNIFICANT IF WHICH RELATES TO FRIDAY. A
CHANCE FOR RAIN IS INCLUDED FOR THURSDAY NIGHT THROUGH FRIDAY FOR
THIS...ALMOST CLIPPER LIKE SYSTEM. GIVEN THAT IT IS MARCH...AND WE
SHOULD NOT HAVE SNOW COVER TO DEAL WITH MID TO LATE WEEK...THESE
SYSTEMS SHOULD BE ABLE TO PRODUCE A SUBSTANTIAL WARM UP AHEAD OF
THEM...LIKELY INTO THE 50S TO LOWER 60S. TIMING OF THEM WILL BE VERY
HARD...IF NOT IMPOSSIBLE THIS FAR OUT LEADING TO A MUCH HIGHER THAN
NORMAL PROBABILITY OF TEMPERATURE FORECAST BUSTS.
ERVIN
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1126 PM CDT SAT MAR 15 2014
A BAND OF LIGHT TO POSSIBLY MODERATE SNOW WILL SLIDE SOUTH ACROSS
MLI/BRL TERMINALS BETWEEN 15/06Z AND 15/09Z. THE SNOW SHOULD LAST
1 TO 3 HOURS WITH MVFR AND POSSIBLY BRIEFLY IFR CONDITIONS IN SNOW.
NE WINDS WILL PICK UP TO 15 TO 20 KTS AND OCCASIONALLY 25 KTS
OVERNIGHT...MAINLY AT BRL/MLI. AFTER THE SNOW ENDS...CONDITIONS
SHOULD IMPROVE TO VFR CONDITIONS WITHIN A FEW HOURS WITH GRADUAL
CLEARING BY MORNING TO MID DAY. THE NE WINDS WILL DIMINISH TO 10
TO 15 KTS BY MID AFTERNOON AS HIGH PRESSURE MOVES IN WITH CLEAR TO
MOSTLY CLEAR SKIES BY 16/00Z.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...FLOOD WATCH THROUGH THIS EVENING FOR HENRY IL-ROCK ISLAND-
WHITESIDE.
MO...NONE.
&&
$$
SYNOPSIS...GROSS
SHORT TERM...GROSS
LONG TERM...ERVIN
AVIATION...NICHOLS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
551 AM CDT Sun Mar 16 2014
...AVIATION UPDATE...
.SHORT TERM...(Today and Tonight)
Issued at 307 AM CDT SUN MAR 16 2014
08Z water vapor imagery shows a shortwave lifting east northeast
through the ARKLATEX region with some energy left behind over ELP.
Also a shortwave trough was noted swinging through eastern NEB.
Surface obs indicate a low pressure center near the ARKLATEX as well
with 3 hr pressure rises across northeast KS around 4 MB. Profiler
data suggests the 850 MB front has moved through most of not all of
the forecast area.
Now that the 850 front has moved through, models indicate dry air
will continue to advect south through the morning. And once the
shortwave trough axis over NEB passes to the east, there should not
be much in the way of forcing for precip. Regional radar has some
light returns across southeast NEB, but this is likely just trace
amounts or flurries with the NEB WFOs getting reports of a dusting
or light accumulations on cars. Therefore the forecast has things
winding down through the morning. The 00Z NAM has backed off on the
strength of the pressure gradient from earlier runs and while
sustained speeds have only flirted with 30 MPH, there have still
been an occasional gust over 40 MPH. Because of this will likely
keep the southern half of the wind advisory going this morning.
However if the pressure gradient weakens enough, we may be able to
cancel it before noon. Models show the boundary layer mixing to
around 850 MB this afternoon. Since there isn`t a great deal of cold
air with the front and the prospects for some good insolation across
north central KS this afternoon, have highs forecast to warm into
the lower and middle 40s. Cloud cover hanging on longer into the
afternoon across far eastern KS is expected to keep afternoon highs
in the upper 30s or around 40. Lows tonight will again be tricky
with skies clearing out and a weak ridge axis passing over the area.
Winds switch around to the south and gradually increase overnight
across north central KS. Think this may aid mixing of the boundary
layer and keep lows in the upper 20s. Elsewhere along the KS river
valley and over east central KS, the ridge axis is expected to keep
winds light for a longer period of the night allowing radiational
cooling to drop lows into the lower 20s especially in the areas
prone to seeing large drops in temps once the wind goes calm.
.LONG TERM...(Monday through Saturday)
Issued at 307 AM CDT SUN MAR 16 2014
Overall drier weather pattern in the extended forecast as a series
of disturbances originating from the Pacific keep higher
precipitation chances further north. Gusty winds continue
throughout the week.
Monday is on track to be a more pleasantly warm day as high pressure
shifts off to the east as southwest winds respond to a developing
surface trough over the western high plains. Wind gusts range
between 20 and 30 mph during the afternoon as dewpoint temperatures
mix into the 20s to low 30s. Decent southwest flow at h85 across
north central KS should pull temps warmer above previous guidance
near 70. Further east, the slightly weaker warm advection limit
readings to the 60s. These conditions will set the area up for very
high fire danger conditions again in the afternoon as minimum
humidity values fall in the low and middle 20s.
Surface trough becomes a closed low as it phases with the
approaching upper wave by Monday evening. Expect southerly winds to
remain gusty Monday evening into Tuesday as the wave passes to our
north, forcing another cold front through Tuesday. 15 to 25 mph
sustained winds from the southwest overnight switch to the west and
northwest behind the front entering north central KS late Tuesday
afternoon. Speeds increase between 20 and 30 mph sustained through
at least midnight Wednesday before gradient wanes. Models are
continuing to trend warmer Tuesday with the increasing warm
advection ahead of the front, however some uncertainty on the
strength of the thermal ridge ahead of the boundary which could
raise current forecast highs in the lower to middle 60s. Slight
chances for rain were mentioned on Tuesday and Tuesday evening for
locations near the Kansas and Nebraska border. The latest ECMWF,
GEM, and SREF indicate upper forcing combined with some saturation
could stretch into our area, however confidence in this occurrence
is low based on high cloud bases and lack of good saturation on
model soundings.
Precipitation chances become less certain Wednesday through Saturday
as zonal flow brings a series embedded disturbances, varied in
timing from each model run. The ECMWF tries to bring another weak
wave behind the exiting trough Wednesday evening while the GFS
depicts ridging and subsidence behind the trough. Will leave dry for
now as this is the first run of the ECMWF depicting this solution.
Somewhat better congruency on Thursday evening into Friday as another
shortwave trough enters the central plains. Have continued to side
with the ECMWF placing the better forcing further north. Soundings
from the GFS depict little moisture available, however with a cold
frontal passage expected Friday, will continue to monitor trends as
there could be some forcing for precip along the boundary. A
stronger upper trough begins to organize off the CA coast by
Saturday with major discrepancies on timing of minor waves ejecting
ahead into northeast Kansas. Have continued a dry forecast for now,
but would not be surprised if better precip chances return at the
end of the week. Passing cold front on Tuesday and Friday will only
cool highs slightly will overall readings through the week in the
50s and 60s. Overnight lows range in the 30s to low 40s.
&&
.AVIATION...(For the 12Z TAFs through 12Z Monday Morning)
Issued at 551 AM CDT SUN MAR 16 2014
Models seem to be handling the light snow band pretty well, which
is expected to exit to the east of TOP and FOE by 15Z. Only trace
amounts have been reported so am not anticipating a major impact
from the light snow. Bigger concern is the MVFR stratus. The
latest RAP wants to hold the back edge of the stratus in the
vicinity of TOP and FOE. Meanwhile most other guidance shows the
low level moisture eroding to the east and south. Will delay the
stratus scattering out at TOP and FOE because of the RAP, but am
not ready to keep MVFR CIGS for most of the day given the surface
low will move east this afternoon and dewpoints across IA and NEB
are in the teens implying the low level dry air should eventually
move into northeast KS.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until Noon CDT today FOR KSZ026-035>040-054>056-
058-059.
&&
$$
SHORT TERM...Wolters
LONG TERM...Bowen
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1212 AM CDT Sun Mar 16 2014
...Updated aviation section...
.SHORT TERM...(This evening through Sunday)
ISSUED AT 339 PM CDT SAT MAR 15 2014
Winds will be the main forecast challenge tonight and how to handle
with the wind advisory headline. Earlier in the day we extended the
advisory to start sooner, especially across the western and northern
counties. All the guidance, including RAP and NAM forecast
soundings, suggest a fairly prolonged period of 25 to 28 knots
sustained this evening through about 09Z. Thereafter, the focus of
the wind will shift into south-central Kansas with the gradient
relaxing roughly west of a Meade to Dodge City to Hays line toward
daybreak. As far as precipitation is concerned, we eliminated POPs
everywhere except south-central Kansas where we kept 20-30 POPs
across mainly Barber County in the low level frontogenetic zone. RAP
and HRRR have shown a persistent convective signal in this area with
several hundred J/kg of MLCAPE. Any convection which does affect
Barber County this evening will quickly move southeast into northern
Oklahoma, so the threat for anything substantial as far as a
prolonged strong or even severe threat is extremely minimal. Low
level cold advection will prevail tonight, but with the winds
keeping the boundary layer mixed, we really won`t see terribly low
temperatures for lows -- mainly in the 29-33F range for much of the
southwest Kansas region. The downslope component in the lower
troposphere will eliminate the cold advection, and with insolation
resuming we should see temperatures Sunday warm up into the upper
40s to near 50 in some locations.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 107 PM CDT SAT MAR 15 2014
Medium range models indicate an upper level ridge axis transitioning
southeastward across the Western High Plains Monday while an upper
level trough of low pressure tracks east-southeast across the
Pacific Northwest. Along with a fairly weak flow aloft, this will
result in dry conditions across western Kansas through Monday
night. The upper level trough will then push further southeast
into the Northern Plains Tuesday setting up precip chances from the
Dakotas southward into Nebraska and possibly Kansas. Although an
attendant cold front is projected to push through western Kansas
early Tuesday, the bulk of the upper level system will pass just to
our north. Along with drier air in the lower levels, little if any
rain is expected Tuesday...so a slight chance for rain seems
reasonable. Drier conditions are then expected to persist through
mid week as the flow aloft becomes more zonal.
Well above normal temperatures are expected Monday as lee side
troughing develops and strengthens across eastern Colorado. This
will set up a low level flow across western Kansas helping to draw
much warmer air into the area with H85 temperatures in the mid
Teens(C) across central Kansas to near 20C closer to the Colorado
border. Look for widespread highs up into the 70s(F) Monday
afternoon. Much cooler temperatures are likely Tuesday as a cold
front pushes through western Kansas early in the day. Colder air
will surges southward into the area with the H85 0C isotherm
reaching as far south as the I-70 corridor by late Tuesday
afternoon. Highs are only expected up into the 50s(F) across
west central Kansas to possibly the lower to mid 60s(F) in south
central Kansas. More seasonal temperatures are expected through
the end of the week as the flow aloft becomes more zonal.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1209 AM CDT SUN MAR 16 2014
Windy conditions continue overnight. Northerly winds will
initially be around 30 knots gusting to 40 then decrease to 20
knots gusting to 30 by late morning. VFR conditions will prevail
with mid clouds AOA080.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 27 73 41 59 / 0 0 10 20
GCK 28 75 40 55 / 0 0 10 20
EHA 32 78 41 54 / 0 0 0 10
LBL 27 78 42 59 / 0 0 0 10
HYS 26 72 40 55 / 0 0 0 10
P28 24 73 42 65 / 0 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 4 AM CDT /3 AM MDT/ early this morning FOR
KSZ030-031-043>046-061>063-074-075-084-085.
WIND ADVISORY until 1 PM CDT this afternoon FOR KSZ064>066-
076>081-086>090.
&&
$$
SHORT TERM...Umscheid
LONG TERM...JJohnson
AVIATION...Hovorka_42
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
604 PM EDT Sun Mar 16 2014
...Forecast Update...
Issued at 600 PM EDT Sun Mar 16 2014
Have a couple of bands of heavier precipitation with lighter precip
surrounding them. One ranges from Tell City to Corydon to Goshen,
with reports coming in that this band is producing mostly snow.
Webcam out of Paoli earlier indicated some brief accumulations
there, but light totals. A second band runs from Hartford to E-town
to Harrodsburg. Type is more mixed with this band, but Dual Pol data
indicate that it has a better chance to be snow from Washington
county in KY to Jessamine county. Had a report from Springfield of
all snow and another report of a rain/snow mix east of Bardstown.
Will try and update locations for precip type with graphical
nowcasts on our webpage the next few hours.
Precipitation is starting to end north of that first band, with a
dry line quickly eroding southward into it. Still looking at some
potential for up to an inch of snow/sleet west of the I-65 corridor,
but a better chance to get into the 1-2 inch range east of I-65 in
the advisory area. Still, those accumulations should not last too
long after the precip ends, given warm ground conditions. Road
temperatures are starting to drop some, now in the mid 30s across
southern Indiana, but still in the 40s over central and southern KY.
At some point later in the evening, likely will convert the Winter
Weather Advisory into a Traveller`s Advisory for wet roads that
could freeze once those temps drop down enough. Fortunately the
place where this happens the quickest...our northern Indiana
counties...also have the least total QPF.
.SHORT TERM (Now through Monday Night)...
Issued at 320 PM EDT Sun Mar 16 2014
It continues to rain across southern Kentucky at this hour, with the
rain mixing in with sleet across northern Kentucky and southern
Indiana. Reports of sleet stretch generally along the I-64 corridor.
There are a few reports of freezing rain on elevated surfaces across
the Bluegrass region, which is certainly possible, on elevated
surfaces. Ground and subsurface temperatures are still generally in
the 40s, a couple lower 50s for subsurface temps.
It took a little bit to finally saturate across the north today, but
once the moisture worked in it did not take long for the warm nose
at about 870 hPa to wetbulb. Latest aircraft soundings indicate this
nose of warm air is rather shallow yet maximizes at about +2C. It
should not take too much longer to cool that to the point where
partial melting will no longer occur and we transition over to all
snow by late this afternoon and evening. The deformation zone is
setting up across southern Indiana and northern Kentucky, pretty
much as advertised.
The latest data, including the RAP have trended the best area of
snow/sleet accumulations a little farther north. The GFS places the
axis of accumulation across southern Indiana and into the far
northern Kentucky Bluegrass region. The NAM accumulation axis is a
little south of this by about one to two counties. The 17Z RAP
(latest as of this writing) still keeps most of the accumulations
south of the Ohio River, but now runs from roughly Jefferson County
Kentucky eastward into the Bluegrass region. The SREF is still the
preferred solution here, which takes into account the both the
northern and southern solutions. The SREF probabilities have seemed
to be the most consistent. So, will continue with the best
accumulation potential being from Perry County in Indiana
east-northeastward to Harrison/Nicholas Counties in Kentucky.
Precipitation will wane late this evening and through the early
morning hours.
Still see no reason to make any changes to the Advisory. Still think
near an inch accumulation for much of the Advisory area, a little
higher (1-2 inches) across the Bluegrass region is on tap. These
accumulations are more likely to occur on grassy areas and elevated
surfaces. With temperatures dropping into the 20s and lower 30s by
daybreak Monday, some slick spots on area roadways could be
possible. If the RAP continues to edge northward with it`s
accumulation axis, then some of the southeastern counties in the
Advisory might be dropped in later updates.
Let`s move on to Monday and warming temperatures this week. Monday
and Monday night will be dry with much lighter winds than today, as
high pressure builds into the Ohio Valley. Temperatures should top
out in the middle to upper 40s during the afternoon hours and drop
off into the upper 20s and 30s Monday night.
.LONG TERM (Tuesday through Sunday)...
Issued at 317 PM EDT Sun Mar 16 2014
================================
Long Term Synoptic Overview
================================
In the long term period, the flow aloft across North America will
remain rather progressive...but fairly zonal. Large negative height
anomalies at 500 hPa will remain located well to the north near
James Bay while an axis of positive height anomalies remains
generally in place across the NE Pacific into Alaska. The
configuration of the upper flow pattern will lead to a storm path
from the NNW to ESE through the period. Two systems look to affect
our region during the extended period. The first will arrive on
Wednesday with a secondary system coming into the region late Friday
and Saturday. This flow pattern will result in more seasonal
temperatures across the forecast area. A moderate warm up is
expected for Tuesday depending on the extent of return flow. A
stronger warm up looks increasingly likely by Friday as a more
robust return flow regime develops in advance of the aforementioned
second system.
================================
Model Preference & Confidence
================================
Overall, the deterministic runs of the GFS and Euro are in fairly
good agreement through the period. There continues to be some
timing issues with regards to the system arriving on Wednesday and
again late Friday and Saturday. However, the timing issues are
showing more convergence with time, so overall confidence is
slightly above normal. Raw model temperatures are a little too cool
and given recent model cold biases, feel that the statistical MOS
guidance is probably a bit better at this point. This would be
especially true Tuesday and Friday afternoon. Generally have gone
on the warmer side of the multi-model consensus which includes the
ensemble solutions. Minimum temperatures look good from a raw model
standpoint. Precipitation timing/amounts have average forecast
confidence, but the overall forecaster confidence trend is on the
upswing.
================================
Sensible Weather Impacts
================================
Overall, milder weather is on tap for the area through much of the
work week. A southerly flow is forecast to take shape late Monday
night into Tuesday. This combined with mid-march sun angles should
result in milder than normal temperatures. As mentioned above, have
gone closer to the statistical guidance here with highs in the lower
to middle 60s in the north and middle 60s down south. Clouds will
increase Tuesday night as the first upper level trough axis and
trailing cold front approach the region. This feature should bring
a band of showers through the region. Have trended the frontal
timing closer to the Euro here with a passage during the day on
Wednesday. Lows Tuesday night will be mild with lows in the
lower-middle 40s and highs on Wednesday topping out in the middle to
upper 50s. Lows Wednesday night look to cool back into the 30s.
High pressure and ridging will build back in for Thursday with highs
warming back into he upper 50s to the lower 60s. A deeper return
flow pattern looks to return Thursday night and into Friday. Friday
looks to be the warmest day of the period. After a morning start in
the lower 40s, temperatures Friday afternoon look to warm into the
upper 60s to near 70 in the north...with 70-72 likely across far
southern KY. With the warmth, this only signals yet another
frontal passage that will occur late Friday night into Saturday
morning. With the warmer profiles and more moisture in the area,
rain showers with some scattered thunderstorms look likely. Again
in the post-frontal wake, we`ll see a cool down after the front
passes with highs on Saturday and Sunday warming into the middle to
upper 50s...while overnight lows remain in the upper 30s to the
lower 40s.
&&
.AVIATION (18Z TAF Update)...
Updated at 138 PM EDT Sun Mar 16 2014
Rain has overspread the TAF sites. Across northern Kentucky, the
rain is beginning to mix with sleet. Have had several reports of
sleet from FTK to near LEX. Temperatures will continue to drop as we
moisten given the low surface dewpoints. So, the changeover will
continue through the afternoon, with all snow expected early this
evening for SDF and LEX. BWG should escape the snow. Given ground
and subsurface temps are at least in the 40s, do not expect too much
frozen precip to accumulate. Ceilings are lowering, albeit slowly.
Still expect MVFR conditions at all sites a little later this
afternoon and especially this evening. Precipitation will move out
late this evening into the overnight hours. This should bring some
improvement to ceilings and visibilities. Otherwise, northeast winds
15-20 knots will gust to 25-30 knots this afternoon and early
evening before diminishing as the surface low moves east tonight.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY until 8 AM EDT /7 AM CDT/ Monday FOR
KYZ023>025-028>043-045>049-053>057-066-067.
IN...WINTER WEATHER ADVISORY until 8 AM EDT /7 AM CDT/ Monday FOR
INZ076>079-083-084-089>092.
&&
$$
Update.........RJS
Short Term.....MJP
Long Term......MJ
Aviation.......MJP
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
327 PM EDT Sun Mar 16 2014
.SHORT TERM (Now through Monday Night)...
Issued at 320 PM EDT Sun Mar 16 2014
It continues to rain across southern Kentucky at this hour, with the
rain mixing in with sleet across northern Kentucky and southern
Indiana. Reports of sleet stretch generally along the I-64 corridor.
There are a few reports of freezing rain on elevated surfaces across
the Bluegrass region, which is certainly possible, on elevated
surfaces. Ground and subsurface temperatures are still generally in
the 40s, a couple lower 50s for subsurface temps.
It took a little bit to finally saturate across the north today, but
once the moisture worked in it did not take long for the warm nose
at about 870 hPa to wetbulb. Latest aircraft soundings indicate this
nose of warm air is rather shallow yet maximizes at about +2C. It
should not take too much longer to cool that to the point where
partial melting will no longer occur and we transition over to all
snow by late this afternoon and evening. The deformation zone is
setting up across southern Indiana and northern Kentucky, pretty
much as advertised.
The latest data, including the RAP have trended the best area of
snow/sleet accumulations a little farther north. The GFS places the
axis of accumulation across southern Indiana and into the far
northern Kentucky Bluegrass region. The NAM accumulation axis is a
little south of this by about one to two counties. The 17Z RAP
(latest as of this writing) still keeps most of the accumulations
south of the Ohio River, but now runs from roughly Jefferson County
Kentucky eastward into the Bluegrass region. The SREF is still the
preferred solution here, which takes into account the both the
northern and southern solutions. The SREF probabilities have seemed
to be the most consistent. So, will continue with the best
accumulation potential being from Perry County in Indiana
east-northeastward to Harrison/Nicholas Counties in Kentucky.
Precipitation will wane late this evening and through the early
morning hours.
Still see no reason to make any changes to the Advisory. Still think
near an inch accumulation for much of the Advisory area, a little
higher (1-2 inches) across the Bluegrass region is on tap. These
accumulations are more likely to occur on grassy areas and elevated
surfaces. With temperatures dropping into the 20s and lower 30s by
daybreak Monday, some slick spots on area roadways could be
possible. If the RAP continues to edge northward with it`s
accumulation axis, then some of the southeastern counties in the
Advisory might be dropped in later updates.
Let`s move on to Monday and warming temperatures this week. Monday
and Monday night will be dry with much lighter winds than today, as
high pressure builds into the Ohio Valley. Temperatures should top
out in the middle to upper 40s during the afternoon hours and drop
off into the upper 20s and 30s Monday night.
.LONG TERM (Tuesday through Sunday)...
Issued at 317 PM EDT Sun Mar 16 2014
================================
Long Term Synoptic Overview
================================
In the long term period, the flow aloft across North America will
remain rather progressive...but fairly zonal. Large negative height
anomalies at 500 hPa will remain located well to the north near
James Bay while an axis of positive height anomalies remains
generally in place across the NE Pacific into Alaska. The
configuration of the upper flow pattern will lead to a storm path
from the NNW to ESE through the period. Two systems look to affect
our region during the extended period. The first will arrive on
Wednesday with a secondary system coming into the region late Friday
and Saturday. This flow pattern will result in more seasonal
temperatures across the forecast area. A moderate warm up is
expected for Tuesday depending on the extent of return flow. A
stronger warm up looks increasingly likely by Friday as a more
robust return flow regime develops in advance of the aforementioned
second system.
================================
Model Preference & Confidence
================================
Overall, the deterministic runs of the GFS and Euro are in fairly
good agreement through the period. There continues to be some
timing issues with regards to the system arriving on Wednesday and
again late Friday and Saturday. However, the timing issues are
showing more convergence with time, so overall confidence is
slightly above normal. Raw model temperatures are a little too cool
and given recent model cold biases, feel that the statistical MOS
guidance is probably a bit better at this point. This would be
especially true Tuesday and Friday afternoon. Generally have gone
on the warmer side of the multi-model consensus which includes the
ensemble solutions. Minimum temperatures look good from a raw model
standpoint. Precipitation timing/amounts have average forecast
confidence, but the overall forecaster confidence trend is on the
upswing.
================================
Sensible Weather Impacts
================================
Overall, milder weather is on tap for the area through much of the
work week. A southerly flow is forecast to take shape late Monday
night into Tuesday. This combined with mid-march sun angles should
result in milder than normal temperatures. As mentioned above, have
gone closer to the statistical guidance here with highs in the lower
to middle 60s in the north and middle 60s down south. Clouds will
increase Tuesday night as the first upper level trough axis and
trailing cold front approach the region. This feature should bring
a band of showers through the region. Have trended the frontal
timing closer to the Euro here with a passage during the day on
Wednesday. Lows Tuesday night will be mild with lows in the
lower-middle 40s and highs on Wednesday topping out in the middle to
upper 50s. Lows Wednesday night look to cool back into the 30s.
High pressure and ridging will build back in for Thursday with highs
warming back into he upper 50s to the lower 60s. A deeper return
flow pattern looks to return Thursday night and into Friday. Friday
looks to be the warmest day of the period. After a morning start in
the lower 40s, temperatures Friday afternoon look to warm into the
upper 60s to near 70 in the north...with 70-72 likely across far
southern KY. With the warmth, this only signals yet another
frontal passage that will occur late Friday night into Saturday
morning. With the warmer profiles and more moisture in the area,
rain showers with some scattered thunderstorms look likely. Again
in the post-frontal wake, we`ll see a cool down after the front
passes with highs on Saturday and Sunday warming into the middle to
upper 50s...while overnight lows remain in the upper 30s to the
lower 40s.
&&
.AVIATION (18Z TAF Update)...
Updated at 138 PM EDT Sun Mar 16 2014
Rain has overspread the TAF sites. Across northern Kentucky, the
rain is beginning to mix with sleet. Have had several reports of
sleet from FTK to near LEX. Temperatures will continue to drop as we
moisten given the low surface dewpoints. So, the changeover will
continue through the afternoon, with all snow expected early this
evening for SDF and LEX. BWG should escape the snow. Given ground
and subsurface temps are at least in the 40s, do not expect too much
frozen precip to accumulate. Ceilings are lowering, albeit slowly.
Still expect MVFR conditions at all sites a little later this
afternoon and especially this evening. Precipitation will move out
late this evening into the overnight hours. This should bring some
improvement to ceilings and visibilities. Otherwise, northeast winds
15-20 knots will gust to 25-30 knots this afternoon and early
evening before diminishing as the surface low moves east tonight.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY until 8 AM EDT /7 AM CDT/ Monday FOR
KYZ023>025-028>043-045>049-053>057-066-067.
IN...WINTER WEATHER ADVISORY until 8 AM EDT /7 AM CDT/ Monday FOR
INZ076>079-083-084-089>092.
&&
$$
Short Term........MJP
Long Term.........MJ
Aviation..........MJP
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
139 PM EDT Sun Mar 16 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1030 AM EDT Sun Mar 16 2014
Rain working in from the southwest has overspread our southern
forecast area, yet is trying to overcome dry air across the northern
third of the CWA. As this occurs, surface temperatures are trending
down as we wetbulb. Dewpoints across our northern half are generally
in the low to middle 20s. Gusty northeast winds continue to try to
advect colder air in here. Temperatures are at or below freezing
just to our northeast. So, with some advection combined with
wetbulbing, temperatures should continue to cool through the morning
and afternoon hours. Latest aircraft soundings indicate a very warm
layer of about +7C at about 870 hPa. Have not come across a sounding
with a dewpoint curve though. Models generally have this warm nose
and cool it rather quickly (wetbulbing) as they indicate quite a bit
of dry air at that level.
Afternoon still looks good for a changeover from rain to a mix,
though may have to fine tune that as the day progresses. The 12Z NAM
has arrived and has shifted the main precip band a little farther
north, which lines up more with 06Z GFS. These place the
accumulations along the Ohio River and eastward into the northern
Bluegrass region. Still think snow and sleet amounts these spit out
are a bit high in places. Watching the RAP this morning shows it
ever so slightly fluctuating by about the width of a county or two
between a southern and northern snow/sleet band. However, this band
is farther south than the NAM and GFS, placing the best
accumulations south of the Ohio River. The SREF probabilities have
seemed to be the most consistent and is what was leaned toward
yesterday. With the 09Z SREF data having just rolled in, it still
depicts the best accumulation potential from Perry County in Indiana
east-northeastward to Harrison/Nicholas Counties in Kentucky. The
SREF seems to capture the slightly more northern GFS/NAM and
southern RAP/NMM.
Given this data, see no reason to make any changes to the running
forecast at this point, just a few minor updates in the very near
term. The Advisory will stand as is for now. Believe our northern
most counties in Indiana (Washington, Scott, Jefferson) still have a
chance to pick up around an inch across their south. Our far
southeast, Casey and Lincoln Counties in Kentucky still have a
chance to pick up around an inch in their north.
.SHORT TERM (Now through Monday)...
Issued at 317 AM EDT Sun Mar 16 2014
...Accumulating Snow Expected This Afternoon and Tonight...
After a beautiful warm day on Saturday, today will bring quite a big
change as wintry weather returns for (hopefully) one last hurrah. A
surface low over Arkansas this morning will track east across the
northern portions of the Gulf Coast states today and this evening. A
large precipitation shield associated with this low will spread into
south central KY by around daybreak or just before and then spread
northward through the morning hours.
Precipitation type is still a challenge with this system. The
forecast hinges on how much cold air will be drawn into the area
today on the northern side of the low pressure system. Central
Indiana this morning has fallen into the mid to upper 30s, so there
is cold air to the north of the forecast area. Additionally, there
is a warm layer aloft that will slowly cool through the day. As
mentioned in previous discussions, this warm layer is not as robust
as in previous systems and therefore will likely not result in
complete melting aloft. This may lead to some sleet as precipitation
transitions from rain to snow from north to south today.
The other challenge with this system is the models are still in some
disagreement as to where a heavier band of precipitation will set
up. The GFS is the farthest north with this band and has it along
the Ohio River while the NAM has it between the Parkways and the
Euro has it across south central KY. Some of the higher resolution
models paint the band just south of the Ohio River into the
Bluegrass region, and this seems a reasonable consensus.
Taking everything into consideration, the forecast remains fairly
close to the previous forecast. It looks like there will be a mix of
rain/snow/sleet across southern Indiana and far north central KY
this morning if the precipitation moves in there that fast. The
transition line will sink southward through the afternoon hours and
into this evening as the colder air filters in. Drier air will
filter in fairly quickly on the back side of the system tonight,
though some lingering freezing drizzle around the Lake Cumberland
area may be possible late tonight. Dry conditions are expected
tomorrow.
Snow totals are tricky given the possibility of sleet and the fact
that initially there will likely be some melting with the antecedent
warm ground. Accumulations will be most likely on grassy and
elevated surfaces, but if there are some heavier bursts of snow
roads may become slick at times. Lowered snow totals just a bit.
Most areas in the Advisory look to receive around an inch with 1-2
inches in the Bluegrass region. Some locally higher amounts are
certainly not out of the question, however. Falling temperatures
tonight also may lead to some slick spots on roadways for the
morning commute Monday.
In addition to the precipitation, winds will become gusty today as
the pressure gradient tightens up across the area. Sustained winds
of 15-25 mph with gusts up to 35 mph can be expected.
.LONG TERM (Monday Night through Saturday)...
Issued at 250 AM EDT Sun Mar 16 2014
A fairly nice work week is in store with overall temps slightly
above normal for a change. The northern stream will remain active
this coming week pushing weak cold fronts through our region Wed and
Fri Night/Sat. Ridging will control the region Tues drawing warm
air northward and allowing temps to rise into the upper 50s and
lower 60s for highs. Tues night the frontal boundary will approach
the area bringing a chance for rain showers late Tues night or Wed.
Long range models vary on timing slightly so will stick with current
forecast for consistency which matches the last few runs of the
ECMWF best. The next front looks to come through sometime Fri night
or Sat. Still a good range in timing/strength amongst models with
this front as well. At this point, neither fronts this week look
too strong or look to contain a great amount of moisture. Think
that light rain showers will likely accompany both fronts. A t-storm
or two may also be possible. Winds may become gusty on either side
of the fronts especially Wed and Sat. Wind gusts in the 20-30 mph
look likely on these days.
As for temps, the area will be in the upper 50s/lower 60s for highs
most of the week. Friday will be a bit warmer, though, in the mid
to upper 60s (maybe even some low 70s) for highs as a strong
southerly wind brings in warmer temps. Low temps will range
throughout the 30s and 40s this week.
&&
.AVIATION (18Z TAF Update)...
Updated at 138 PM EDT Sun Mar 16 2014
Rain has overspread the TAF sites. Across northern Kentucky, the
rain is beginning to mix with sleet. Have had several reports of
sleet from FTK to near LEX. Temperatures will continue to drop as we
moisten given the low surface dewpoints. So, the changeover will
continue through the afternoon, with all snow expected early this
evening for SDF and LEX. BWG should escape the snow. Given ground
and subsurface temps are at least in the 40s, do not expect too much
frozen precip to accumulate. Ceilings are lowering, albeit slowly.
Still expect MVFR conditions at all sites a little later this
afternoon and especially this evening. Precipitation will move out
late this evening into the overnight hours. This should bring some
improvement to ceilings and visibilities. Otherwise, northeast winds
15-20 knots will gust to 25-30 knots this afternoon and early
evening before diminishing as the surface low moves east tonight.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY until 8 AM EDT /7 AM CDT/ Monday FOR
KYZ023>025-028>043-045>049-053>057-066-067.
IN...WINTER WEATHER ADVISORY until 8 AM EDT /7 AM CDT/ Monday FOR
INZ076>079-083-084-089>092.
&&
$$
Update.........MJP
Short Term.....EER
Long Term......AMS
Aviation.......MJP
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1032 AM EDT Sun Mar 16 2014
...Forecast Update...
Issued at 1030 AM EDT Sun Mar 16 2014
Rain working in from the southwest has overspread our southern
forecast area, yet is trying to overcome dry air across the northern
third of the CWA. As this occurs, surface temperatures are trending
down as we wetbulb. Dewpoints across our northern half are generally
in the low to middle 20s. Gusty northeast winds continue to try to
advect colder air in here. Temperatures are at or below freezing
just to our northeast. So, with some advection combined with
wetbulbing, temperatures should continue to cool through the morning
and afternoon hours. Latest aircraft soundings indicate a very warm
layer of about +7C at about 870 hPa. Have not come across a sounding
with a dewpoint curve though. Models generally have this warm nose
and cool it rather quickly (wetbulbing) as they indicate quite a bit
of dry air at that level.
Afternoon still looks good for a changeover from rain to a mix,
though may have to fine tune that as the day progresses. The 12Z NAM
has arrived and has shifted the main precip band a little farther
north, which lines up more with 06Z GFS. These place the
accumulations along the Ohio River and eastward into the northern
Bluegrass region. Still think snow and sleet amounts these spit out
are a bit high in places. Watching the RAP this morning shows it
ever so slightly fluctuating by about the width of a county or two
between a southern and northern snow/sleet band. However, this band
is farther south than the NAM and GFS, placing the best
accumulations south of the Ohio River. The SREF probabilities have
seemed to be the most consistent and is what was leaned toward
yesterday. With the 09Z SREF data having just rolled in, it still
depicts the best accumulation potential from Perry County in Indiana
east-northeastward to Harrison/Nicholas Counties in Kentucky. The
SREF seems to capture the slightly more northern GFS/NAM and
southern RAP/NMM.
Given this data, see no reason to make any changes to the running
forecast at this point, just a few minor updates in the very near
term. The Advisory will stand as is for now. Believe our northern
most counties in Indiana (Washington, Scott, Jefferson) still have a
chance to pick up around an inch across their south. Our far
southeast, Casey and Lincoln Counties in Kentucky still have a
chance to pick up around an inch in their north.
.SHORT TERM (Now through Monday)...
Issued at 317 AM EDT Sun Mar 16 2014
...Accumulating Snow Expected This Afternoon and Tonight...
After a beautiful warm day on Saturday, today will bring quite a big
change as wintry weather returns for (hopefully) one last hurrah. A
surface low over Arkansas this morning will track east across the
northern portions of the Gulf Coast states today and this evening. A
large precipitation shield associated with this low will spread into
south central KY by around daybreak or just before and then spread
northward through the morning hours.
Precipitation type is still a challenge with this system. The
forecast hinges on how much cold air will be drawn into the area
today on the northern side of the low pressure system. Central
Indiana this morning has fallen into the mid to upper 30s, so there
is cold air to the north of the forecast area. Additionally, there
is a warm layer aloft that will slowly cool through the day. As
mentioned in previous discussions, this warm layer is not as robust
as in previous systems and therefore will likely not result in
complete melting aloft. This may lead to some sleet as precipitation
transitions from rain to snow from north to south today.
The other challenge with this system is the models are still in some
disagreement as to where a heavier band of precipitation will set
up. The GFS is the farthest north with this band and has it along
the Ohio River while the NAM has it between the Parkways and the
Euro has it across south central KY. Some of the higher resolution
models paint the band just south of the Ohio River into the
Bluegrass region, and this seems a reasonable consensus.
Taking everything into consideration, the forecast remains fairly
close to the previous forecast. It looks like there will be a mix of
rain/snow/sleet across southern Indiana and far north central KY
this morning if the precipitation moves in there that fast. The
transition line will sink southward through the afternoon hours and
into this evening as the colder air filters in. Drier air will
filter in fairly quickly on the back side of the system tonight,
though some lingering freezing drizzle around the Lake Cumberland
area may be possible late tonight. Dry conditions are expected
tomorrow.
Snow totals are tricky given the possibility of sleet and the fact
that initially there will likely be some melting with the antecedent
warm ground. Accumulations will be most likely on grassy and
elevated surfaces, but if there are some heavier bursts of snow
roads may become slick at times. Lowered snow totals just a bit.
Most areas in the Advisory look to receive around an inch with 1-2
inches in the Bluegrass region. Some locally higher amounts are
certainly not out of the question, however. Falling temperatures
tonight also may lead to some slick spots on roadways for the
morning commute Monday.
In addition to the precipitation, winds will become gusty today as
the pressure gradient tightens up across the area. Sustained winds
of 15-25 mph with gusts up to 35 mph can be expected.
.LONG TERM (Monday Night through Saturday)...
Issued at 250 AM EDT Sun Mar 16 2014
A fairly nice work week is in store with overall temps slightly
above normal for a change. The northern stream will remain active
this coming week pushing weak cold fronts through our region Wed and
Fri Night/Sat. Ridging will control the region Tues drawing warm
air northward and allowing temps to rise into the upper 50s and
lower 60s for highs. Tues night the frontal boundary will approach
the area bringing a chance for rain showers late Tues night or Wed.
Long range models vary on timing slightly so will stick with current
forecast for consistency which matches the last few runs of the
ECMWF best. The next front looks to come through sometime Fri night
or Sat. Still a good range in timing/strength amongst models with
this front as well. At this point, neither fronts this week look
too strong or look to contain a great amount of moisture. Think
that light rain showers will likely accompany both fronts. A t-storm
or two may also be possible. Winds may become gusty on either side
of the fronts especially Wed and Sat. Wind gusts in the 20-30 mph
look likely on these days.
As for temps, the area will be in the upper 50s/lower 60s for highs
most of the week. Friday will be a bit warmer, though, in the mid
to upper 60s (maybe even some low 70s) for highs as a strong
southerly wind brings in warmer temps. Low temps will range
throughout the 30s and 40s this week.
&&
.AVIATION (12Z TAF Update)...
Updated at 645 AM EDT Sun Mar 16 2014
Winds have already started to become gusty this morning as a low
pressure system passes the area to the south. Winds through the day
will be out of the northeast and sustained from 10-20 knots with
gusts to around 25-30 knots. Winds will relax a bit tonight, but
still remain gusty.
Rain will overspread the area this morning. Ceilings are expected to
lower to MVFR with this rain. BWG may see IFR ceilings for awhile as
well. Rain will change over to snow at LEX and SDF this evening as
colder air filters in. Precipitation will move out late this evening
into the overnight hours. This should bring some improvement to
ceilings and visibilities.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...WINTER WEATHER ADVISORY from 2 PM EDT /1 PM CDT/ this afternoon
to 8 AM EDT /7 AM CDT/ Monday FOR KYZ023>025-028>043-
045>049-053>057-066-067.
IN...WINTER WEATHER ADVISORY from 2 PM EDT /1 PM CDT/ this afternoon
to 8 AM EDT /7 AM CDT/ Monday FOR INZ076>079-083-084-
089>092.
&&
$$
Update.........MJP
Short Term.....EER
Long Term......AMS
Aviation.......EER
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
539 AM CDT SUN MAR 16 2014
.AVIATION...
SCATTERED TSTMS ACROSS DEEP EAST INTO WESTERN LOUISIANA TO BEGIN
THE 12Z TAF PERIOD WILL MOVE SOUTHEAST OUT OF THE AREA BY 15Z.
EXPECT IFR CIGS AND VSBYS...STRONG WIND AND SEVERE TURBULENCE WITH
THESE STORMS. OTHERWISE...MOSTLY MVFR CIGS AND STRONG NORTH TO NORTHWEST
WIND WILL BE THE MAIN AVIATION CONCERNS THROUGH 17/12Z. THE STRONG
WIND WILL RESULT IN MODERATE LOW LEVEL TURBULENCE TODAY WHICH WILL
CONTINUE TO 17/03Z BEFORE WINDS BEGIN TO DIMINISH. SURFACE WIND
TODAY NORTHWEST 15 TO 20 KTS WITH GUSTS TO 30 KTS. /14/
&&
.PREV DISCUSSION... /ISSUED 445 AM CDT SUN MAR 16 2014/
DISCUSSION...
QUITE A FEW CHALLENGES IN THE FCST FOR THE NEXT 24 HRS. LET US SEE
HOW MANY I CAN COVER IN THIS AFD. FIRST...POPS FOR TODAY. BULK OF
THE CONVECTION HAS EXITED THE AREA. NEW CLUSTER HAS DEVELOP ACROSS
DEEP E TX OVER THE LAST FEW HRS. RADAR TRENDS AND 06Z HRRR SUGGEST
THIS LINE WILL PERSIST INTO OUR LA PARISHES SO HAVE MAINTAINED
CHANCE POPS THROUGH 15Z AND THEN BEGAN TO TAPER POPS FROM W TO E
BEYOND THAT TIME. REMAINDER OF THE AREA HAS LARGELY BEEN DRY
SLOTTED BUT AREAS N OF I-30...PARTICULARLY SE OK/EXTREME SW AR
HAVE A GOOD CHANCE AT SEEING SOME WRAP AROUND PRECIP ON THE BACK
SIDE OF THE SFC LOW. LARGE SCALE ASCENT FROM THE UPPER TROUGH
DIGGING SE ACROSS TX MAY BE ENOUGH FOR A FEW SHWRS ACROSS THE
REMAINDER OF THE AREA BUT EFFECTS OF DRY SLOTTING MAY BE TOO MUCH
TO OVERCOME. HAVE TENDED TO FAVOR THE DRIER NAM SOLUTION.
NEXT...WINDS TODAY. NWLY WINDS EXPECTED TO REALLY PICK UP LATER
THIS MORNING ACROSS THE NW HALF OF THE AREA AND THEN ACROSS THE
REST OF THE AREA BY THE EARLY AFTERNOON. SPEEDS SHOULD BE OVER
LAKE WIND ADV CRITERIA. TIGHT PRESSURE GRADIENT WILL LIKELY
PERSIST INTO THE EVENING SO THE ADVISORY WILL RUN UNTIL 06Z
TONIGHT.
THIRD...TEMPS TODAY. THE STRONG NWLY WINDS AND COLD AIR ADVECTION
INTO THE REGION WILL LIKELY RESULT IN FALLING TEMPS TODAY SHORTLY
AFTER 12Z-13Z. DELAY OF THE STRONG WINDS AND COLD AIR MAY ALLOW FOR SOME
LIMITED DAYTIME HEATING GENERALLY SE OF A KLFK-KMLU LINE BEFORE
18Z...BEYOND WHICH TEMPS SHOULD BEGIN TO DECREASE.
FOURTH...POSSIBILITY OF WINTRY PRECIP TONIGHT/EARLY MONDAY
MORNING. EVEN THOUGH MANY LOCATIONS HAVE ALREADY REACHED OR ARE
NEAR AVERAGE LAST FREEZE DATES WINTER WEATHER CAN STILL HAPPEN IN
THIS REGION THIS LATE IN THE SEASON. NEAR OR BELOW FREEZING TEMPS
ARE LIKELY NORTH OF A KOSA-KELD LINE. MORE NLY COMPONENT TO LOW
LVL WINDS STILL KEEP CONFIDENCE HIGHER IN COLD AIR DAMMING BY THE
OUACHITAS TO THE NORTH. HOWEVER...ENOUGH COLD AIR SHOULD FILTER INTO
SRN AR TO SUPPORT A LIGHT MIX OF RAIN...SLEET...AND SNOW. BESIDES
THE ISSUE OF HAVING ENOUGH COLD AIR TO SUPPORT WINTRY PRECIP
TYPES...THERE IS STILL A QUESTION REGARDING IF THERE WILL BE ENOUGH
MOISTURE IN THE AREA FOR PRECIP. MODELS MAINTAIN SOME LIGHT QPF
DURING THE EARLY MORNING HRS SO WILL KEEP SLIGHT CHANCE POPS IN
THE FCST. IF WINTRY PRECIP DOES OCCUR...IMPACTS ARE EXPECTED TO BE
MINIMAL.
TEMPS SHOULD QUICKLY REBOUND BACK INTO THE 70S AREAWIDE BY TUESDAY
DUE TO STRONG SLY FLOW AND WAA AHEAD OF THE NEXT FAST MOVING FRONT
DUE TO ARRIVE LATE TUESDAY. ECMWF STILL FCSTING QPF WITH THIS
FRONT BUT DO NOT THINK THERE WILL BE ENOUGH TIME FOR SUFFICIENT
MOISTURE RETURN TO SUPPORT ANY RAIN CHANCES. TEMPS MAY BE KNOCKED
BACK DOWN BY A COUPLE OF DEGREES BUT SHOULD REMAIN NEAR OR ABOVE
CLIMO THROUGH THE REMAINDER OF THE FCST PERIOD. NEXT SIGNIFICANT
CHANCES FOR RAIN NOT EXPECTED UNTIL NEXT WEEKEND. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 60 37 58 40 73 / 30 20 10 10 10
MLU 66 36 53 36 72 / 30 20 10 10 10
DEQ 56 30 56 34 71 / 50 20 10 10 10
TXK 57 35 54 40 71 / 40 20 10 10 10
ELD 58 32 55 36 72 / 40 20 10 10 10
TYR 57 35 57 43 75 / 30 10 10 10 10
GGG 58 35 57 41 73 / 30 10 10 10 10
LFK 62 37 57 39 75 / 30 10 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...LAKE WIND ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: ARZ059-070-071.
LAKE WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM CDT MONDAY
FOR THE FOLLOWING ZONES: ARZ050-051-060-061-072-073.
LA...LAKE WIND ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: LAZ001-002.
LAKE WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM CDT MONDAY
FOR THE FOLLOWING ZONES: LAZ003>006-010>014-017>022.
OK...LAKE WIND ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: OKZ077.
TX...LAKE WIND ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: TXZ096-097-108>112-124>126-136>138-149>151.
LAKE WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM CDT MONDAY
FOR THE FOLLOWING ZONES: TXZ152-153-165>167.
&&
$$
14/09
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
445 AM CDT SUN MAR 16 2014
.DISCUSSION...
QUITE A FEW CHALLENGES IN THE FCST FOR THE NEXT 24 HRS. LET US SEE
HOW MANY I CAN COVER IN THIS AFD. FIRST...POPS FOR TODAY. BULK OF
THE CONVECTION HAS EXITED THE AREA. NEW CLUSTER HAS DEVELOP ACROSS
DEEP E TX OVER THE LAST FEW HRS. RADAR TRENDS AND 06Z HRRR SUGGEST
THIS LINE WILL PERSIST INTO OUR LA PARISHES SO HAVE MAINTAINED
CHANCE POPS THROUGH 15Z AND THEN BEGAN TO TAPER POPS FROM W TO E
BEYOND THAT TIME. REMAINDER OF THE AREA HAS LARGELY BEEN DRY
SLOTTED BUT AREAS N OF I-30...PARTICULARLY SE OK/EXTREME SW AR
HAVE A GOOD CHANCE AT SEEING SOME WRAP AROUND PRECIP ON THE BACK
SIDE OF THE SFC LOW. LARGE SCALE ASCENT FROM THE UPPER TROUGH
DIGGING SE ACROSS TX MAY BE ENOUGH FOR A FEW SHWRS ACROSS THE
REMAINDER OF THE AREA BUT EFFECTS OF DRY SLOTTING MAY BE TOO MUCH
TO OVERCOME. HAVE TENDED TO FAVOR THE DRIER NAM SOLUTION.
NEXT...WINDS TODAY. NWLY WINDS EXPECTED TO REALLY PICK UP LATER
THIS MORNING ACROSS THE NW HALF OF THE AREA AND THEN ACROSS THE
REST OF THE AREA BY THE EARLY AFTERNOON. SPEEDS SHOULD BE OVER
LAKE WIND ADV CRITERIA. TIGHT PRESSURE GRADIENT WILL LIKELY
PERSIST INTO THE EVENING SO THE ADVISORY WILL RUN UNTIL 06Z
TONIGHT.
THIRD...TEMPS TODAY. THE STRONG NWLY WINDS AND COLD AIR ADVECTION
INTO THE REGION WILL LIKELY RESULT IN FALLING TEMPS TODAY SHORTLY
AFTER 12Z-13Z. DELAY OF THE STRONG WINDS AND COLD AIR MAY ALLOW FOR SOME
LIMITED DAYTIME HEATING GENERALLY SE OF A KLFK-KMLU LINE BEFORE
18Z...BEYOND WHICH TEMPS SHOULD BEGIN TO DECREASE.
FOURTH...POSSIBILITY OF WINTRY PRECIP TONIGHT/EARLY MONDAY
MORNING. EVEN THOUGH MANY LOCATIONS HAVE ALREADY REACHED OR ARE
NEAR AVERAGE LAST FREEZE DATES WINTER WEATHER CAN STILL HAPPEN IN
THIS REGION THIS LATE IN THE SEASON. NEAR OR BELOW FREEZING TEMPS
ARE LIKELY NORTH OF A KOSA-KELD LINE. MORE NLY COMPONENT TO LOW
LVL WINDS STILL KEEP CONFIDENCE HIGHER IN COLD AIR DAMMING BY THE
OUACHITAS TO THE NORTH. HOWEVER...ENOUGH COLD AIR SHOULD FILTER INTO
SRN AR TO SUPPORT A LIGHT MIX OF RAIN...SLEET...AND SNOW. BESIDES
THE ISSUE OF HAVING ENOUGH COLD AIR TO SUPPORT WINTRY PRECIP
TYPES...THERE IS STILL A QUESTION REGARDING IF THERE WILL BE ENOUGH
MOISTURE IN THE AREA FOR PRECIP. MODELS MAINTAIN SOME LIGHT QPF
DURING THE EARLY MORNING HRS SO WILL KEEP SLIGHT CHANCE POPS IN
THE FCST. IF WINTRY PRECIP DOES OCCUR...IMPACTS ARE EXPECTED TO BE
MINIMAL.
TEMPS SHOULD QUICKLY REBOUND BACK INTO THE 70S AREAWIDE BY TUESDAY
DUE TO STRONG SLY FLOW AND WAA AHEAD OF THE NEXT FAST MOVING FRONT
DUE TO ARRIVE LATE TUESDAY. ECMWF STILL FCSTING QPF WITH THIS
FRONT BUT DO NOT THINK THERE WILL BE ENOUGH TIME FOR SUFFICIENT
MOISTURE RETURN TO SUPPORT ANY RAIN CHANCES. TEMPS MAY BE KNOCKED
BACK DOWN BY A COUPLE OF DEGREES BUT SHOULD REMAIN NEAR OR ABOVE
CLIMO THROUGH THE REMAINDER OF THE FCST PERIOD. NEXT SIGNIFICANT
CHANCES FOR RAIN NOT EXPECTED UNTIL NEXT WEEKEND. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 60 37 58 40 73 / 30 20 10 10 10
MLU 66 36 53 36 72 / 30 20 10 10 10
DEQ 56 30 56 34 71 / 50 20 10 10 10
TXK 57 35 54 40 71 / 40 20 10 10 10
ELD 58 32 55 36 72 / 40 20 10 10 10
TYR 57 35 57 43 75 / 30 10 10 10 10
GGG 58 35 57 41 73 / 30 10 10 10 10
LFK 62 37 57 39 75 / 30 10 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...LAKE WIND ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: ARZ059-070-071.
LAKE WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM CDT MONDAY
FOR THE FOLLOWING ZONES: ARZ050-051-060-061-072-073.
LA...LAKE WIND ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: LAZ001-002.
LAKE WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM CDT MONDAY
FOR THE FOLLOWING ZONES: LAZ003>006-010>014-017>022.
OK...LAKE WIND ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: OKZ077.
TX...LAKE WIND ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: TXZ096-097-108>112-124>126-136>138-149>151.
LAKE WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 1 AM CDT MONDAY
FOR THE FOLLOWING ZONES: TXZ152-153-165>167.
&&
$$
09/14
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
944 PM EDT MON MAR 17 2014
.SYNOPSIS...
HIGH PRESSURE WILL BRING DRY WEATHER UNTIL THE PASSAGE OF A MID
WEEK COLD FRONT.
&&
.NEAR TERM /THROUGH TUESDAY/...
LATEST RAOBS...UPR AIR CHARTS AND RAP MDL PROGS INDICATE CLOUD
COVER WL PERSIST OVRNGT FOR MUCH OF THE AREA...THOUGH SOME AREAS
OF CLRG WL DVLP. THERE IS AN OUTSIDE CHC FOR FZG DRIZZLE IN THE
HIGHEST TERRAIN IN MD/WV WITH LLVL MOISTURE POOLING...BUT WITH
SHALLOW MOISTURE THINK CHCS ARE TOO LOW FOR FCST INCLUSION ATTM.
RIDGING ON TUE WL KEEP DRY AND WARMER WEA ACRS THE AREA AS CLDS
GRDLY DCR. AFT BLO AVG TEMPS TNGT...READINGS SHOULD APCH SEASONAL
AVGS TUE WITH WK WRM AIR ADVCTN.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
MIDWESTERN CYCLONE IS A LITTLE DEEPER THAN PREVIOUS RUNS
CONSEQUENTLY 12Z NCEP CHAIN HAS SLOWED DOWN PCPN ONSET BY A FEW
HOURS. WINDS INCREASE TUESDAY NIGHT ALLOWING ATMOSPHERE TO REMAIN MIXED.
DEEPER VALLEYS MAY RADIATE IN THE EVENING THEN RISE AFTER MIDNIGHT
WHEN NOCTURNAL INVERSION BREAKS. AS MSTR PILES UP WITH UPSLOPE
FLOW...ADDED CHANCE OF FREEZING DRIZZLE FOR ERN GARRETT...NOT
ENOUGH CONFIDENCE TO GO N INTO FAYETTE ATT.
BAROCLINIC ZONE CROSSES WEDNESDAY AFTERNOON EVENING. BUFR
SOUNDINGS PORTRAY A SHORT WINDOW OF GUSTY WIND POTENTIAL...HOWEVER
WITH LATER FROPA NOT INTERSECTING TIME PERIOD OF GREATEST MIXING
HEIGHTS...VALUES SHOULD BE NOT AS HIGH AS PREVIOUS RUNS. LOWERED
WINDS GUSTS A TAD AND CONFINED PEAK VALUES IN OHIO WHERE TIMING IS
MOST FAVORABLE. AT THIS JUNCTURE...CAN NOT RULE OUT A GUST PUSHING
WIND ADVISORY CRITERIA /46 MPH/...HOWEVER DURATION WILL BE BRIEF
AND LIKELY NOT HANDLED BY A LONG FUSE HEADLINE. ONE THING TO WATCH
IS WIND STRENGTH ACROSS EASTERN FAYETTE AND WESTMO WED. THIS SETUP
CAN LEAD TO ENHANCED SPEEDS IN THESE AREAS.
THERMODYNAMIC PARAMETERS REMAIN NOT CONDUCIVE FOR THUNDERSTORM
POTENTIAL...THUS MAINTAIN A THUNDER FREE FORECAST. ANOTHER POSITIVE
OF THE DELAYED PCPN ONSET TIME IS COLD AIR SHOULD BE SCOURED OUT OF
LLVLS OWING TO NO PTYPE ISSUES.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
COOLER AND DRIER CONDITIONS RETURN TO THE AREA FOR THE END OF THE
WORK WEEK...HOWEVER COLD ADVECTION IS UNLIKELY TO BE ANYTHING
CLOSE TO WHAT WE HAVE SEEN IN RECENT EPISODES. SHORT WAVE RIDGING
SEEMS LIKELY TO BE OVER THE AREA ON THE MAJORITY OF THE MODELS AND
ENSEMBLES FOR FRIDAY...LIKELY RESULTING IN A MOSTLY DRY/WARMER DAY
BEFORE THE CONSENSUS FAVORS ANOTHER SYSTEM FRIDAY NIGHT/EARLY
SATURDAY.
BEYOND THE PASSAGE OF THE FRIDAY NIGHT/SATURDAY SYSTEM...STRONG
MODEL/ENSEMBLE CONSENSUS SEEMS TO BE DEVELOPING THAT RIDGING
SHOULD AGAIN BUILD OVER THE WESTERN HALF OF NORTH AMERICA...ARCING
ALL THE WAY UP TO THE ARCTIC OCEAN...WITH DEEP TROUGHING AGAIN
RETURNING TO THE EASTERN TWO-THIRDS OF NORTH AMERICA. THIS MAY
WELL OPEN UP THE FLOOD GATES YET AGAIN TO ANOTHER STRONG BLAST OF
COLD AIR BY THE SECOND HALF OF THE WEEKEND AND EARLY NEXT WEEK.
MODEL AND ENSEMBLE 850 MB TEMPERATURES SEEM TO ALL FALL TOWARD THE
NEGATIVE MID-TEENS WITH 2 METER TEMPERATURES FALLING TOWARD THE
LOWER 20S FOR HIGHS. STATISTICAL GUIDANCE STILL FAVORS 40S DUE TO
THE CLIMATOLOGY SKEWING OF THE MOS GUIDANCE IN THE EXTENDED.
BECAUSE OF MODEL AGREEMENT...THE FORECAST WAS ADJUSTED WELL BELOW
MOS GUIDANCE WITH HIGHS LARGELY NEAR FREEZING TOWARD THE END OF
THE EXTENDED FORECAST.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
PERSISTENT STRATUS/STRATOCU LYR RMNS OVR THE UPR OH REGION...ALBEIT
AT VFR LVLS. TAFS WERE ADJUSTED USING THE LATEST RUC RH FIELDS
WHICH SUGGEST MSTR WL CONT TO POOL ALNG INVERTED TROF INTO THE
PREDAWN HRS...AS OPPOSED TO DISSIPATION AS PREVIOUSLY PROGGED.
VFR WL CONT...WITH SELY SFC WND ON TUESDAY AS LOW PRES DEEPENS OVR
THE MIDWEST.
.OUTLOOK.../MONDAY NIGHT THROUGH SATURDAY/...
GENL RESTRICTIONS AND LLVL WIND SHEAR ARE PROBABLE ON WEDNESDAY
AS STRONG LOW PRES SLIDES ACRS THE GREAT LAKES AND SHUNTS A CDFNT
ACRS THE UPR OH VALLEY REGION.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
07/15
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
320 PM EDT SUN MAR 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM EDT SUN MAR 16 2014
00Z RAOBS/LATEST WV LOOP AND RUC ANALYSIS SHOW CONFLUENT NW FLOW ALF
OVER THE UPR GRT LKS BTWN PERSISTENT DEEP UPR TROF CENTERED NEAR
JAMES BAY AND MEAN UPR RDG OVER THE W. IN THE CORE OF THE COLD
AIRMASS THAT IS DOMINATING ERN CANADA AND THE NE CONUS...00Z H5/H85
TEMPS WERE AS LO AS -45C/-26C AT MOOSONEE AT THE S END OF JAMES BAY.
SFC HI PRES UNDER THE CONFLUENT UPR FLOW IS MOVING INTO NW MN EARLY
THIS MRNG. THE STEADY N WIND AHEAD OF THIS FEATURE IS ADVECTING
COLDER AIR INTO THE UPR LKS. DESPITE THE LLVL DRYNESS OF THE AIRMASS
DEPICTED ON THE 00Z INL/YPL RAOBS...WHERE THE PWAT WAS 0.05 AND 0.04
INCH RESPECTIVELY OR ONLY 25 PCT OF NORMAL...GENERAL ACYC NATURE OF
THE LLVL FLOW...AND THE EXTENSIVE ICE COVER ON LK SUP...SOME SCT LK
CLDS HAVE FORMED OVER THE NRN TIER OF THE U.P. BUT AT SOME OF THE
COLDER SPOTS OVER THE WRN INTERIOR...THE COMBINATION OF LIGHTER
WINDS AND THE VERY DRY AIR HAS CAUSED TEMPS TO FALL WELL BLO ZERO.
TO THE W OF THE SFC HI IN THE NRN PLAINS/SCNTRL CANADA...WAD BTWN
THE HI CENTER AND A SHRTV DROPPING SE OVER THE UPR RDG INTO SCNTRL
CANADA IS BRINGING LOTS OF CLDS AND SOME LGT SN.
MAIN FCST CONCERNS IN THE SHORT TERM ARE TEMPS FOR TODAY AND THEN
CLD TRENDS/IMPACT ON TEMPS TNGT AS WELL AS CHC FOR SN LATER TNGT
OVER THE W.
TODAY...ARCTIC HI PRES CENTER IS FCST TO DRIFT SLOWLY SE OVER UPR MI
TODAY AND TO NEAR TRAVERSE CITY BY 00Z MON. EXPECT ANY LK CLDS OVER
THE NRN TIER THIS MRNG TO DISSIPATE WITH THE ARRIVAL OF THE HI AND
DIURNAL HEATING. MIXING TO ABOUT H875 AS OBSVD UPSTREAM YDAY ON FCST
SDNGS YIELDS HI TEMPS REACHING THE 20-25 RANGE NEAR THE WI BORDER
AWAY FM ANY LK COOLING/ICE COVER.
TNGT...AS THE ARCTIC HI CENTER SHIFTS INTO SE ONTARIO BY 12Z MON AND
A SHRTWV SLIDING ESEWD IN THE WNW FLOW ALF ARND PERSISTENT UPR TROF
OVER QUEBEC MOVES TO NEAR LK WINNIPEG...DEEP...LARGER SCALE SSW
FLOW/ISENTROPIC ASCENT BEST SHOWN ON THE 280-290K SFCS /H8-6/ WL
RESULT IN INCRSG CLDS W-E. ALTHOUGH SOME LGT SN MAY REACH THE WRN
CWA LATE UNDER THE DEEPENING SATURATION/MORE IMPRESSIVE DEEP LYR
QVECTOR CNVGC/UPR DVGC IN EXIT REGION OF 100KT H3 JET MAX ASSOCIATED
WITH THE SHRTWV...TENACIOUS DRIER LLVL AIR ASSOCIATED WITH ONLY SLOW
MOVING SFC HI PRES OVER SE ONTARIO HELD IN PLACE BY NW FLOW ON THE
WRN FLANK OF QUEBEC TROF SHOULD KEEP MOST OF THE LAND CWA DRY THRU
THE NGT. MIN TEMPS WL BE LOWEST OVER THE E HALF CLOSER TO THE SFC
HI...WHERE WINDS WL BE LIGHTER AND WAD CLDS WL ARRIVE THE LATEST...
HELPING TO MAINTAIN PWAT AS LO AS 40-50 PCT OF NORMAL AT NEWBERRY
THRU 12Z MON. INCRSG CLDS AND DOWNSLOPE S WINDS OVER THE W NEAR LK
SUP WL GREATLY RESTRICT THE DIURNAL FALL OF TEMP THERE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 318 PM EDT SUN MAR 16 2014
MAIN FORECAST CONCERNS ARE IN THE MIDDLE OF THE WEEK AS A
SYSTEM SHOULD IMPACT THE CWA...POSSIBLY BRINGING MIXED PRECIP AND SOME
SIGNIFICANT SNOWFALL AMOUNTS TO PARTS OF THE CWA. OTHERWISE...ONLY
MINOR PRECIP WITH MINIMAL IMPACTS IS EXPECTED.
FOR THE MID WEEK SYSTEM...THERE CONTINUES TO BE A LOT OF UNCERTAINTY
AS MODEL RUN TO RUN CONTINUITY HAS BEEN FAIR AT BEST FOR MOST MODELS
AND MODEL TO MODEL AGREEMENT IS LIMITED. THE POOR CONTINUITY AND HIGH
UNCERTAINTY IS UNDERSTANDABLE GIVEN THAT THE UPPER LEVEL ENERGY
DRIVING THIS SYSTEM IS CURRENTLY OVER THE GULF OF AK. MODEL TO MODEL
AGREEMENT IS NOT ALL THAT BAD IN GENERAL...BUT THE FINE DETAILS
NEEDED FOR PTYPE AND PRECIP AMOUNT FORECASTS ARE FAR FROM
SETTLED...WHICH IS TYPICAL FOR WHERE THE ENERGY IS CURRENTLY
LOCATED. WOULD NOT BE SURPRISE TO SEE MODEL SPREAD INCREASE
SIGNIFICANTLY ONCE THE SYSTEM MOVES INTO THE BETTER OBSERVATION
NETWORK OF THE PACIFIC NW CONUS ON MON. IN A TYPICAL SITUATION WITH
THIS TYPE OF SYSTEM...SHOULD START SEEING BETTER MODEL AGREEMENT AND
HAVE GREATER CONFIDENCE TUE AS THE SYSTEM MOVES LEEWARD OF THE
ROCKIES...ESPECIALLY SINCE THE SHORTWAVE WILL BE MOVING INTO A
STRONG RIDGE UP UNTIL THIS POINT...LEADING TO ADDITIONAL UNCERTAINTY
WITH HOW WELL IT DOES AFTER INTERACTING WITH THE RIDGE. MODELS SHOW
THE SHORTWAVE DEEPENING AND BECOMING NEGATIVELY TILTED AFTER LEEWARD
CYCLOGENESIS OCCURS E OF THE ROCKIES AND NRN/SRN JET STREAM
INTERACTION OCCURS ON THE S SIDE OF THE UPPER TROUGH. EXACTLY WHERE
AND TO WHAT MAGNITUDE THE LOW DEEPENS IS LESS AGREED ON BETWEEN THE
MODELS AND WILL LIKELY CHANGE IN FUTURE RUNS ANYWAY. MODELS THEN
SHOW THE SFC LOW MOVING OVER OR NEAR THE CWA SOMETIME TUE NIGHT INTO
WED. THE 12Z/16 NAM IS FARTHEST NW WITH THE TRACK OF THE SFC LOW IN
BRINGING IT ACROSS WRN LAKE SUPERIOR...WHILE THE 00Z/16 GLOBAL GEM
IS FARTHEST SE IN BRINGING IT FROM NEAR CHICAGO TO NEAR GAYLORD. THE
12Z/16 GFS BRINGS THE SFC LOW FROM NEAR MENOMINEE TO NEAR
NEWBERRY...WHILE THE 00Z/16 ECMWF IS FROM MILWAUKEE TO NEAR THE SOO.
WHILE A MIDDLE OF THE GROUND APPROACH IS CERTAINLY A REASONABLE
APPROACH FOR THE FORECAST...AT THIS POINT IT IS QUITE DIFFICULT TO
PREFER ANY ONE SOLUTION OVER ANOTHER GIVEN THE UNCERTAINTY ALREADY
DISCUSSED. THE POSSIBILITIES FOR THE TRACK OF THIS SYSTEM LEAD TO
SUBSTANTIAL DIFFERENCES IN THE PTYPE AND PRECIP AMOUNT...WITH THE
FARTHER S SOLUTION OF THE GEM FAVORING MORE SNOW BOTH AS THE SYSTEM
PASSES AND AHEAD OF THE SYSTEM IN THE FGEN AREA THAT ALL MODELS SHOW
TO THE N/NE OF THE SYSTEM. THE FARTHER N SOLUTION OF THE NAM WOULD
RESULT IN LESS OVERALL PRECIP AND MORE OF THAT BEING MIXED OR ALL
LIQUID. THE CONSENSUS APPROACH LEADS TO MIXED PRECIP OVER THE SERN
PORTIONS OF THE CWA...AND MORE SNOW OVER THE NWRN CWA. AGAIN...THESE
DETAILS WILL LIKELY CHANGE OVER THE NEXT COUPLE OF DAYS. COULD NOT
FIND SIGNIFICANT JUSTIFICATION TO SIGNIFICANTLY CHANGE THE PREVIOUS
FORECAST. IT REMAINS WORTH MENTIONING THAT SIGNIFICANT SNOWFALL
AMOUNTS ARE POSSIBLE SOMEWHERE IN THE REGION BUT DETAILS ARE STILL
UNCERTAIN. DEFINITELY A TRICKY FORECAST THAT WILL HAVE TO BE FINE
TUNED SIGNIFICANTLY OVER THE COMING DAYS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 129 PM EDT SUN MAR 16 2014
VFR CEILINGS AND VIS WILL REMAIN THROUGH THIS EVENING...AS DRY HIGH
PRESSURE MOVES FROM CENTRAL UPPER MI EARLY THIS AFTERNOON TO LOWER
MI AND LAKE HURON BY 06Z...AND ALONG THE S MANITOBA/QUEBEC BORDER BY
12Z MONDAY. IN IT/S WAKE EXPECT INCREASING S WINDS WITH HIGH CLOUDS
SLOWLY BUILDING IN OVERNIGHT. LLWS WILL BE POSSIBLE FROM APPROX
08-15Z AT ALL 3 SITES /WITH THE BEST CHANCE AT IWD/. CLOUDS WILL
SLOWLY LOWER MONDAY MORNING...WITH MVFR CEILINGS AT IWD AND CMX
PRIOR TO 18Z WITH LIGHT SNOW...AS LOW PRESSURE NEARS FROM THE N
PLAINS STATES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 AM EDT SUN MAR 16 2014
LIGHT WINDS UNDER 20 KTS INTO TNGT ASSOCIATED WITH A PASSING HI PRES
CENTER WILL BECOME S AND INCREASE UP TO 20-25 KTS LATE TONIGHT INTO
MON UNDER THE SHARPENING PRES GRADIENT BETWEEN THE RETREATING HI TO
THE E AND A LO PRES DEVELOPING IN THE NCENTRAL PLAINS. ALTHOUGH THE
WINDS MAY DIMINISH LATER MON AND MON NIGHT AS THE HI CENTER SLIPS
FARTHER TO THE E AND THE GRADIENT WEAKENS...WINDS WILL BACK MORE TO
THE E AND INCREASE UP TO 25-30 KTS ON TUE AS THE PLAINS LO MOVES
TOWARD THE UPPER MIDWEST. THE FLOW WILL BACK TO THE NW UP TO 25 KTS
ON WED INTO THU ONCE THIS LOW SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
129 PM EDT SUN MAR 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM EDT SUN MAR 16 2014
00Z RAOBS/LATEST WV LOOP AND RUC ANALYSIS SHOW CONFLUENT NW FLOW ALF
OVER THE UPR GRT LKS BTWN PERSISTENT DEEP UPR TROF CENTERED NEAR
JAMES BAY AND MEAN UPR RDG OVER THE W. IN THE CORE OF THE COLD
AIRMASS THAT IS DOMINATING ERN CANADA AND THE NE CONUS...00Z H5/H85
TEMPS WERE AS LO AS -45C/-26C AT MOOSONEE AT THE S END OF JAMES BAY.
SFC HI PRES UNDER THE CONFLUENT UPR FLOW IS MOVING INTO NW MN EARLY
THIS MRNG. THE STEADY N WIND AHEAD OF THIS FEATURE IS ADVECTING
COLDER AIR INTO THE UPR LKS. DESPITE THE LLVL DRYNESS OF THE AIRMASS
DEPICTED ON THE 00Z INL/YPL RAOBS...WHERE THE PWAT WAS 0.05 AND 0.04
INCH RESPECTIVELY OR ONLY 25 PCT OF NORMAL...GENERAL ACYC NATURE OF
THE LLVL FLOW...AND THE EXTENSIVE ICE COVER ON LK SUP...SOME SCT LK
CLDS HAVE FORMED OVER THE NRN TIER OF THE U.P. BUT AT SOME OF THE
COLDER SPOTS OVER THE WRN INTERIOR...THE COMBINATION OF LIGHTER
WINDS AND THE VERY DRY AIR HAS CAUSED TEMPS TO FALL WELL BLO ZERO.
TO THE W OF THE SFC HI IN THE NRN PLAINS/SCNTRL CANADA...WAD BTWN
THE HI CENTER AND A SHRTV DROPPING SE OVER THE UPR RDG INTO SCNTRL
CANADA IS BRINGING LOTS OF CLDS AND SOME LGT SN.
MAIN FCST CONCERNS IN THE SHORT TERM ARE TEMPS FOR TODAY AND THEN
CLD TRENDS/IMPACT ON TEMPS TNGT AS WELL AS CHC FOR SN LATER TNGT
OVER THE W.
TODAY...ARCTIC HI PRES CENTER IS FCST TO DRIFT SLOWLY SE OVER UPR MI
TODAY AND TO NEAR TRAVERSE CITY BY 00Z MON. EXPECT ANY LK CLDS OVER
THE NRN TIER THIS MRNG TO DISSIPATE WITH THE ARRIVAL OF THE HI AND
DIURNAL HEATING. MIXING TO ABOUT H875 AS OBSVD UPSTREAM YDAY ON FCST
SDNGS YIELDS HI TEMPS REACHING THE 20-25 RANGE NEAR THE WI BORDER
AWAY FM ANY LK COOLING/ICE COVER.
TNGT...AS THE ARCTIC HI CENTER SHIFTS INTO SE ONTARIO BY 12Z MON AND
A SHRTWV SLIDING ESEWD IN THE WNW FLOW ALF ARND PERSISTENT UPR TROF
OVER QUEBEC MOVES TO NEAR LK WINNIPEG...DEEP...LARGER SCALE SSW
FLOW/ISENTROPIC ASCENT BEST SHOWN ON THE 280-290K SFCS /H8-6/ WL
RESULT IN INCRSG CLDS W-E. ALTHOUGH SOME LGT SN MAY REACH THE WRN
CWA LATE UNDER THE DEEPENING SATURATION/MORE IMPRESSIVE DEEP LYR
QVECTOR CNVGC/UPR DVGC IN EXIT REGION OF 100KT H3 JET MAX ASSOCIATED
WITH THE SHRTWV...TENACIOUS DRIER LLVL AIR ASSOCIATED WITH ONLY SLOW
MOVING SFC HI PRES OVER SE ONTARIO HELD IN PLACE BY NW FLOW ON THE
WRN FLANK OF QUEBEC TROF SHOULD KEEP MOST OF THE LAND CWA DRY THRU
THE NGT. MIN TEMPS WL BE LOWEST OVER THE E HALF CLOSER TO THE SFC
HI...WHERE WINDS WL BE LIGHTER AND WAD CLDS WL ARRIVE THE LATEST...
HELPING TO MAINTAIN PWAT AS LO AS 40-50 PCT OF NORMAL AT NEWBERRY
THRU 12Z MON. INCRSG CLDS AND DOWNSLOPE S WINDS OVER THE W NEAR LK
SUP WL GREATLY RESTRICT THE DIURNAL FALL OF TEMP THERE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 433 AM EDT SUN MAR 16 2014
FOCUS FOR THE UPCOMING WEEK IS ON LOW PRESSURE SYSTEM THAT LIFTS
ACROSS THE UPPER GREAT LAKES TUESDAY NIGHT INTO WEDNESDAY. BUT
FIRST THINGS FIRST AS SOME ACCUMULATING SNOW AND BLSN MAY OCCUR ON
MONDAY OVER AT LEAST NORTHWEST CWA.
SHORTWAVE CURRENTLY NOSING ACROSS CNTRL ALBERTA SHOWING UP WELL ON
WV LOOP. WAVE DIGS ESE TOWARD LK SUPERIOR REGION LATE TONIGHT AND
THEN SLIDES TO THE NORTH OF LK SUPERIOR IN ONTARIO BY MONDAY EVENING.
ALL THE MAIN MODELS SHOW A LOT OF MID LEVEL MOISTURE WITH LIFT
OCCURRING WITHIN THE DGZ. MAIN ISSUE IS LOW-LEVEL RH AS THERE IS
SIGNAL THAT DRY AIR ADVECTION WILL KEEP MUCH SNOW FM REACHING THE
EASTERN CWA. STRONGEST LIFT VIA THE WAVE AND WARM AIR ADVECTION AND
ISENTROPIC ASCENT ON 280-290K SFCS /H8-H6/ OCCURS OVER NW CWA...VCNTY
OF KEWEENAW PENINSULA. MIXING RATIOS TO 2G/KG AT H7 AND THE FOCUSED
LARGER SCALE FORCING POINT TO ACCUMULATING SNOW FM MID MORNING
THROUGH MID-LATE AFTN. IN ADDITION...GUSTY SOUTHERLY WINDS OVER 20
MPH MAY RESULT IN PATCHY BLSN AS WELL. POTENTIAL THAT BETTER
FORCING/LOW LEVEL MOISTURE MAY EVEN BUMP FARTHER NORTH AS ECMWF AND
NAM SHOWS...SO WILL NOT GO WITH LIKELY POPS QUITE YET...BUT WILL SHOW
HIGHER POP GRADIENT WITH HIGH CHANCES NW WITH SLIGHT CHANCES TO NO
MENTION OF POPS OVER SOUTH AND EAST CWA. TEMPS WILL SHOW A WARMING
TREND WITH UPR 20S WEST AND LOWER 20S EAST THOUGH GUSTY SOUTH WINDS
WILL PROVIDE A BITE TO THE WARMER TEMPS.
WARM AIR ADVECTION CONTINUES INTO MONDAY NIGHT AND TUESDAY AS PRIMARY
UPPER LEVEL TROUGH PUSHES ACROSS THE PLAINS. HINT THERE MAY BE A LEAD
SHORTWAVE AHEAD OF THE TROUGH COMING ACROSS UPR LAKES ON MONDAY
EVENING. ECMWF STRONGEST BUT GEM-NH AND EVEN GFS SHOW SOMETHING
SIMILAR. BUMPED POPS TO CHANCE IN THE EVENING FOR MAINLY WEST HALF.
LATER MONDAY NIGHT INTO TUESDAY...BETTER FORCING TAKES SHAPE TO THE
WEST MAINLY OVER MINNESOTA ALONG SFC-H85 TROUGH AXIS AND WITHIN
DEVELOPING AREA OF MID-LEVEL FGEN AND DIVERGENCE FM RIGHT ENTRANCE
JET FORCING. NET RESULT IS SHARPER EDGE OF MAIN AREA OF PRECIPITATION
BY TUESDAY. KEPT CHANCES BANKED OVER FAR WEST CWA...WHILE LOWER H85
RH SHOULD KEEP REST OF CWA MAINLY DRY ON TUESDAY...BARRING ANY MORE
SHORTWAVES WORKING THROUGH. SHIELD OF THICKER MID CLOUDS WILL KEEP
TEMPS IN THE LOW-MID 30S MOST AREAS...THOUGH A RUN INTO THE LOWER 40S
COULD OCCUR OVER WEST AND SOUTHWEST IF CLOUDS THIN OUT.
NOW ONTO THE PRIMARY SYSTEM OF THIS WEEK. SFC PATTERN AND MODEL
FORECAST H85 TEMPS SHOW WARM LAYER WILL BE FACTOR LATER TUESDAY
NIGHT INTO WEDNESDAY AS PLAINS UPPER LEVEL TROUGH BECOMES NEGATIVELY
TILTED AND AS 250MB DIVERGENCE INCREASES ATOP STRONG WARM AND MOIST
ADVECTION IN LOW-LEVELS. PERIOD OF MOST WIDESPREAD PRECIPITATION
WOULD BE FROM 09Z-18Z WEDNESDAY WITH COLD AIR ADVECTION AND CYCLONIC
FLOW ON BACKSIDE OF SFC-H85 LOW FURTHER BOOSTING PRECIP TOTALS ALONG
LK SUPERIOR 18Z WEDNESDAY THROUGH 06Z THURSDAY. SEVERAL INCHES OF
SNOW POSSIBLE WITH THE SYSTEM...BUT EXACTLY WHERE IS THE QUESTION.
CURRENTLY THE LINE BETWEEN SNOW AND MIXED PRECIPITATION /SLEET AND
FREEZING RAIN BOTH POSSIBLE BASED ON SOUNDINGS AND 1000-850MB AND
850-700MB THICKNESSES/ IS EXPECTED TO SET UP OVER CNTRL CWA. MODELS
HAVE SHOWN TYPICAL RUN TO RUN CONSISTENCY ISSUES AND ARE ALSO NOT
AGREEING WELL WITH EACH OTHER AND THIS WILL LIKELY CONTINUE INTO
EARLY THIS WEEK UNTIL THE SYSTEM /WHICH IS STILL COMING TOGETHER
OVER THE PACIFIC TO THE SOUTH OF ALASKA AND WEST OF BRITISH
COLUMBIA/ IS THOROUGHLY SAMPLED BY RAOB NETWORK AND THE MODELS
ULTIMATELY GET HANDLE ON WHERE THE SFC LOW WILL TRACK. LATEST MODELS
HAVE OVERALL TRENDED FARTHER EAST WITH SFC LOW AND COOLER WITH H85
TEMPS. DID NOT MAKE TOO MANY LARGE CHANGES TO PTYPE IN GRIDS.
FOLLOWING BLEND OF PREVIOUS MODELS LOCATION OF SFC LOW AND WARM
LAYER...KEPT MENTION OF ALL PTYPES IN FOR WEDNESDAY OVER THE EAST
CWA...WHILE MAINLY HAVE A MIX OF SNOW AND SLEET FOR CNTRL CWA...AND
ONLY SNOW IN THE WESTERN CWA.
BEYOND THE SYSTEM...LINGERING CYCLONIC FLOW IN WAKE OF THE SFC LOW
AND UPR LAKES IN VICINITY OF TROUGH AXIS ALOFT WILL LIKELY KEEP
PRECIP ON COLD SIDE OF SYSTEM PERSISTING WELL INTO WEDNESDAY NIGHT.
TURNED ALL PCPN BACK TO SNOW BY 00Z THURSDAY. THEN...SMALL CHANCES
FOR SNOW SHOWERS JUSTIFIED FOR AT LEAST FIRST PART OF THURSDAY WITH
HIGHER 1000-850MB RH AND WEAKLY CYCLONIC NW FLOW. FOR BOTH OF THESE
PERIODS...INCREASED POPS OVER WHAT MODEL CONSENSUS SHOWED.
SFC RIDGE AXIS EXPANDS FROM OHIO VALLEY ACROSS WESTERN GREAT LAKES
IN CONFLUENT FLOW ALOFT THURSDAY NIGHT INTO FRIDAY. ANY LINGERING
AFFECTS FM CLOUDS OR LIGHT LAKE EFFECT SHOULD WANE...ALLOWING FOR
TEMPS TO FALL OFF OVERNIGHT INTO FRIDAY MORNING. PREFERRED ECMWF
SHOWING MORE NW FLOW ALOFT VERSUS GFS WHICH TENDS TO FLATTEN THE
FLOW TOO QUICK. THUS...DISCOUNTED FARTHER NORTH QPF THAT GFS SHOWS
IMPACTING SOUTHERN CWA AS EARLY AS 06Z FRIDAY. SEEMS MUCH TOO QUICK
AND TOO FAR NORTH. LATEST ECMWF DID BUMP FARTHER NORTH WITH WAVE
MOVING THROUGH...SO KEPT CONSENSUS SMALL CHANCES FOR FAR SCNTRL CWA
FRIDAY INTO FRIDAY NIGHT.
REST OF EXTENDED FEATURES NW FLOW IN LOW-LEVELS BTWN DEVELOPING LOW
FOR THE NORTHEAST AND SFC HIGH CNTRL CANADA INTO THE PLAINS. 15MAR
12Z RUN OF ECMWF WAS SHOWING ANOTHER PUSH OF CHILLY AIR WITH H85
TEMPS NEARING -20C. THOUGH GEM-NH LOOKS LIKE THE GFS FRIDAY BEYOND
THAT IT ALSO SHOWS A COLD PLUNGE BACK ACROSS THE GREAT LAKES.
OVERALL NO MATTER WHAT MODEL IS FAVORED...NO SIGNIFCANT OR LASTING
WARM UPS ARE SEEN ANYTIME SOON.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 129 PM EDT SUN MAR 16 2014
VFR CEILINGS AND VIS WILL REMAIN THROUGH THIS EVENING...AS DRY HIGH
PRESSURE MOVES FROM CENTRAL UPPER MI EARLY THIS AFTERNOON TO LOWER
MI AND LAKE HURON BY 06Z...AND ALONG THE S MANITOBA/QUEBEC BORDER BY
12Z MONDAY. IN IT/S WAKE EXPECT INCREASING S WINDS WITH HIGH CLOUDS
SLOWLY BUILDING IN OVERNIGHT. LLWS WILL BE POSSIBLE FROM APPROX
08-15Z AT ALL 3 SITES /WITH THE BEST CHANCE AT IWD/. CLOUDS WILL
SLOWLY LOWER MONDAY MORNING...WITH MVFR CEILINGS AT IWD AND CMX
PRIOR TO 18Z WITH LIGHT SNOW...AS LOW PRESSURE NEARS FROM THE N
PLAINS STATES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 AM EDT SUN MAR 16 2014
LIGHT WINDS UNDER 20 KTS INTO TNGT ASSOCIATED WITH A PASSING HI PRES
CENTER WILL BECOME S AND INCREASE UP TO 20-25 KTS LATE TONIGHT INTO
MON UNDER THE SHARPENING PRES GRADIENT BETWEEN THE RETREATING HI TO
THE E AND A LO PRES DEVELOPING IN THE NCENTRAL PLAINS. ALTHOUGH THE
WINDS MAY DIMINISH LATER MON AND MON NIGHT AS THE HI CENTER SLIPS
FARTHER TO THE E AND THE GRADIENT WEAKENS...WINDS WILL BACK MORE TO
THE E AND INCREASE UP TO 25-30 KTS ON TUE AS THE PLAINS LO MOVES
TOWARD THE UPPER MIDWEST. THE FLOW WILL BACK TO THE NW UP TO 25 KTS
ON WED INTO THU ONCE THIS LOW SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KF
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
725 AM EDT SUN MAR 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM EDT SUN MAR 16 2014
00Z RAOBS/LATEST WV LOOP AND RUC ANALYSIS SHOW CONFLUENT NW FLOW ALF
OVER THE UPR GRT LKS BTWN PERSISTENT DEEP UPR TROF CENTERED NEAR
JAMES BAY AND MEAN UPR RDG OVER THE W. IN THE CORE OF THE COLD
AIRMASS THAT IS DOMINATING ERN CANADA AND THE NE CONUS...00Z H5/H85
TEMPS WERE AS LO AS -45C/-26C AT MOOSONEE AT THE S END OF JAMES BAY.
SFC HI PRES UNDER THE CONFLUENT UPR FLOW IS MOVING INTO NW MN EARLY
THIS MRNG. THE STEADY N WIND AHEAD OF THIS FEATURE IS ADVECTING
COLDER AIR INTO THE UPR LKS. DESPITE THE LLVL DRYNESS OF THE AIRMASS
DEPICTED ON THE 00Z INL/YPL RAOBS...WHERE THE PWAT WAS 0.05 AND 0.04
INCH RESPECTIVELY OR ONLY 25 PCT OF NORMAL...GENERAL ACYC NATURE OF
THE LLVL FLOW...AND THE EXTENSIVE ICE COVER ON LK SUP...SOME SCT LK
CLDS HAVE FORMED OVER THE NRN TIER OF THE U.P. BUT AT SOME OF THE
COLDER SPOTS OVER THE WRN INTERIOR...THE COMBINATION OF LIGHTER
WINDS AND THE VERY DRY AIR HAS CAUSED TEMPS TO FALL WELL BLO ZERO.
TO THE W OF THE SFC HI IN THE NRN PLAINS/SCNTRL CANADA...WAD BTWN
THE HI CENTER AND A SHRTV DROPPING SE OVER THE UPR RDG INTO SCNTRL
CANADA IS BRINGING LOTS OF CLDS AND SOME LGT SN.
MAIN FCST CONCERNS IN THE SHORT TERM ARE TEMPS FOR TODAY AND THEN
CLD TRENDS/IMPACT ON TEMPS TNGT AS WELL AS CHC FOR SN LATER TNGT
OVER THE W.
TODAY...ARCTIC HI PRES CENTER IS FCST TO DRIFT SLOWLY SE OVER UPR MI
TODAY AND TO NEAR TRAVERSE CITY BY 00Z MON. EXPECT ANY LK CLDS OVER
THE NRN TIER THIS MRNG TO DISSIPATE WITH THE ARRIVAL OF THE HI AND
DIURNAL HEATING. MIXING TO ABOUT H875 AS OBSVD UPSTREAM YDAY ON FCST
SDNGS YIELDS HI TEMPS REACHING THE 20-25 RANGE NEAR THE WI BORDER
AWAY FM ANY LK COOLING/ICE COVER.
TNGT...AS THE ARCTIC HI CENTER SHIFTS INTO SE ONTARIO BY 12Z MON AND
A SHRTWV SLIDING ESEWD IN THE WNW FLOW ALF ARND PERSISTENT UPR TROF
OVER QUEBEC MOVES TO NEAR LK WINNIPEG...DEEP...LARGER SCALE SSW
FLOW/ISENTROPIC ASCENT BEST SHOWN ON THE 280-290K SFCS /H8-6/ WL
RESULT IN INCRSG CLDS W-E. ALTHOUGH SOME LGT SN MAY REACH THE WRN
CWA LATE UNDER THE DEEPENING SATURATION/MORE IMPRESSIVE DEEP LYR
QVECTOR CNVGC/UPR DVGC IN EXIT REGION OF 100KT H3 JET MAX ASSOCIATED
WITH THE SHRTWV...TENACIOUS DRIER LLVL AIR ASSOCIATED WITH ONLY SLOW
MOVING SFC HI PRES OVER SE ONTARIO HELD IN PLACE BY NW FLOW ON THE
WRN FLANK OF QUEBEC TROF SHOULD KEEP MOST OF THE LAND CWA DRY THRU
THE NGT. MIN TEMPS WL BE LOWEST OVER THE E HALF CLOSER TO THE SFC
HI...WHERE WINDS WL BE LIGHTER AND WAD CLDS WL ARRIVE THE LATEST...
HELPING TO MAINTAIN PWAT AS LO AS 40-50 PCT OF NORMAL AT NEWBERRY
THRU 12Z MON. INCRSG CLDS AND DOWNSLOPE S WINDS OVER THE W NEAR LK
SUP WL GREATLY RESTRICT THE DIURNAL FALL OF TEMP THERE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 433 AM EDT SUN MAR 16 2014
FOCUS FOR THE UPCOMING WEEK IS ON LOW PRESSURE SYSTEM THAT LIFTS
ACROSS THE UPPER GREAT LAKES TUESDAY NIGHT INTO WEDNESDAY. BUT
FIRST THINGS FIRST AS SOME ACCUMULATING SNOW AND BLSN MAY OCCUR ON
MONDAY OVER AT LEAST NORTHWEST CWA.
SHORTWAVE CURRENTLY NOSING ACROSS CNTRL ALBERTA SHOWING UP WELL ON
WV LOOP. WAVE DIGS ESE TOWARD LK SUPERIOR REGION LATE TONIGHT AND
THEN SLIDES TO THE NORTH OF LK SUPERIOR IN ONTARIO BY MONDAY EVENING.
ALL THE MAIN MODELS SHOW A LOT OF MID LEVEL MOISTURE WITH LIFT
OCCURRING WITHIN THE DGZ. MAIN ISSUE IS LOW-LEVEL RH AS THERE IS
SIGNAL THAT DRY AIR ADVECTION WILL KEEP MUCH SNOW FM REACHING THE
EASTERN CWA. STRONGEST LIFT VIA THE WAVE AND WARM AIR ADVECTION AND
ISENTROPIC ASCENT ON 280-290K SFCS /H8-H6/ OCCURS OVER NW CWA...VCNTY
OF KEWEENAW PENINSULA. MIXING RATIOS TO 2G/KG AT H7 AND THE FOCUSED
LARGER SCALE FORCING POINT TO ACCUMULATING SNOW FM MID MORNING
THROUGH MID-LATE AFTN. IN ADDITION...GUSTY SOUTHERLY WINDS OVER 20
MPH MAY RESULT IN PATCHY BLSN AS WELL. POTENTIAL THAT BETTER
FORCING/LOW LEVEL MOISTURE MAY EVEN BUMP FARTHER NORTH AS ECMWF AND
NAM SHOWS...SO WILL NOT GO WITH LIKELY POPS QUITE YET...BUT WILL SHOW
HIGHER POP GRADIENT WITH HIGH CHANCES NW WITH SLIGHT CHANCES TO NO
MENTION OF POPS OVER SOUTH AND EAST CWA. TEMPS WILL SHOW A WARMING
TREND WITH UPR 20S WEST AND LOWER 20S EAST THOUGH GUSTY SOUTH WINDS
WILL PROVIDE A BITE TO THE WARMER TEMPS.
WARM AIR ADVECTION CONTINUES INTO MONDAY NIGHT AND TUESDAY AS PRIMARY
UPPER LEVEL TROUGH PUSHES ACROSS THE PLAINS. HINT THERE MAY BE A LEAD
SHORTWAVE AHEAD OF THE TROUGH COMING ACROSS UPR LAKES ON MONDAY
EVENING. ECMWF STRONGEST BUT GEM-NH AND EVEN GFS SHOW SOMETHING
SIMILAR. BUMPED POPS TO CHANCE IN THE EVENING FOR MAINLY WEST HALF.
LATER MONDAY NIGHT INTO TUESDAY...BETTER FORCING TAKES SHAPE TO THE
WEST MAINLY OVER MINNESOTA ALONG SFC-H85 TROUGH AXIS AND WITHIN
DEVELOPING AREA OF MID-LEVEL FGEN AND DIVERGENCE FM RIGHT ENTRANCE
JET FORCING. NET RESULT IS SHARPER EDGE OF MAIN AREA OF PRECIPITATION
BY TUESDAY. KEPT CHANCES BANKED OVER FAR WEST CWA...WHILE LOWER H85
RH SHOULD KEEP REST OF CWA MAINLY DRY ON TUESDAY...BARRING ANY MORE
SHORTWAVES WORKING THROUGH. SHIELD OF THICKER MID CLOUDS WILL KEEP
TEMPS IN THE LOW-MID 30S MOST AREAS...THOUGH A RUN INTO THE LOWER 40S
COULD OCCUR OVER WEST AND SOUTHWEST IF CLOUDS THIN OUT.
NOW ONTO THE PRIMARY SYSTEM OF THIS WEEK. SFC PATTERN AND MODEL
FORECAST H85 TEMPS SHOW WARM LAYER WILL BE FACTOR LATER TUESDAY
NIGHT INTO WEDNESDAY AS PLAINS UPPER LEVEL TROUGH BECOMES NEGATIVELY
TILTED AND AS 250MB DIVERGENCE INCREASES ATOP STRONG WARM AND MOIST
ADVECTION IN LOW-LEVELS. PERIOD OF MOST WIDESPREAD PRECIPITATION
WOULD BE FROM 09Z-18Z WEDNESDAY WITH COLD AIR ADVECTION AND CYCLONIC
FLOW ON BACKSIDE OF SFC-H85 LOW FURTHER BOOSTING PRECIP TOTALS ALONG
LK SUPERIOR 18Z WEDNESDAY THROUGH 06Z THURSDAY. SEVERAL INCHES OF
SNOW POSSIBLE WITH THE SYSTEM...BUT EXACTLY WHERE IS THE QUESTION.
CURRENTLY THE LINE BETWEEN SNOW AND MIXED PRECIPITATION /SLEET AND
FREEZING RAIN BOTH POSSIBLE BASED ON SOUNDINGS AND 1000-850MB AND
850-700MB THICKNESSES/ IS EXPECTED TO SET UP OVER CNTRL CWA. MODELS
HAVE SHOWN TYPICAL RUN TO RUN CONSISTENCY ISSUES AND ARE ALSO NOT
AGREEING WELL WITH EACH OTHER AND THIS WILL LIKELY CONTINUE INTO
EARLY THIS WEEK UNTIL THE SYSTEM /WHICH IS STILL COMING TOGETHER
OVER THE PACIFIC TO THE SOUTH OF ALASKA AND WEST OF BRITISH
COLUMBIA/ IS THOROUGHLY SAMPLED BY RAOB NETWORK AND THE MODELS
ULTIMATELY GET HANDLE ON WHERE THE SFC LOW WILL TRACK. LATEST MODELS
HAVE OVERALL TRENDED FARTHER EAST WITH SFC LOW AND COOLER WITH H85
TEMPS. DID NOT MAKE TOO MANY LARGE CHANGES TO PTYPE IN GRIDS.
FOLLOWING BLEND OF PREVIOUS MODELS LOCATION OF SFC LOW AND WARM
LAYER...KEPT MENTION OF ALL PTYPES IN FOR WEDNESDAY OVER THE EAST
CWA...WHILE MAINLY HAVE A MIX OF SNOW AND SLEET FOR CNTRL CWA...AND
ONLY SNOW IN THE WESTERN CWA.
BEYOND THE SYSTEM...LINGERING CYCLONIC FLOW IN WAKE OF THE SFC LOW
AND UPR LAKES IN VICINITY OF TROUGH AXIS ALOFT WILL LIKELY KEEP
PRECIP ON COLD SIDE OF SYSTEM PERSISTING WELL INTO WEDNESDAY NIGHT.
TURNED ALL PCPN BACK TO SNOW BY 00Z THURSDAY. THEN...SMALL CHANCES
FOR SNOW SHOWERS JUSTIFIED FOR AT LEAST FIRST PART OF THURSDAY WITH
HIGHER 1000-850MB RH AND WEAKLY CYCLONIC NW FLOW. FOR BOTH OF THESE
PERIODS...INCREASED POPS OVER WHAT MODEL CONSENSUS SHOWED.
SFC RIDGE AXIS EXPANDS FROM OHIO VALLEY ACROSS WESTERN GREAT LAKES
IN CONFLUENT FLOW ALOFT THURSDAY NIGHT INTO FRIDAY. ANY LINGERING
AFFECTS FM CLOUDS OR LIGHT LAKE EFFECT SHOULD WANE...ALLOWING FOR
TEMPS TO FALL OFF OVERNIGHT INTO FRIDAY MORNING. PREFERRED ECMWF
SHOWING MORE NW FLOW ALOFT VERSUS GFS WHICH TENDS TO FLATTEN THE
FLOW TOO QUICK. THUS...DISCOUNTED FARTHER NORTH QPF THAT GFS SHOWS
IMPACTING SOUTHERN CWA AS EARLY AS 06Z FRIDAY. SEEMS MUCH TOO QUICK
AND TOO FAR NORTH. LATEST ECMWF DID BUMP FARTHER NORTH WITH WAVE
MOVING THROUGH...SO KEPT CONSENSUS SMALL CHANCES FOR FAR SCNTRL CWA
FRIDAY INTO FRIDAY NIGHT.
REST OF EXTENDED FEATURES NW FLOW IN LOW-LEVELS BTWN DEVELOPING LOW
FOR THE NORTHEAST AND SFC HIGH CNTRL CANADA INTO THE PLAINS. 15MAR
12Z RUN OF ECMWF WAS SHOWING ANOTHER PUSH OF CHILLY AIR WITH H85
TEMPS NEARING -20C. THOUGH GEM-NH LOOKS LIKE THE GFS FRIDAY BEYOND
THAT IT ALSO SHOWS A COLD PLUNGE BACK ACROSS THE GREAT LAKES.
OVERALL NO MATTER WHAT MODEL IS FAVORED...NO SIGNIFCANT OR LASTING
WARM UPS ARE SEEN ANYTIME SOON.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 722 AM EDT SUN MAR 16 2014
ANY LINGERING MVFR CLOUDS AT SAW EARLY IN THE TAF PERIOD SHOULD GIVE
WAY TO VFR WX AS HI PRES SLIDES ACROSS UPR MI TDAY. ALTHOUGH THERE WL
BE INCRSG HI/MID CLDS TNGT ASSOCIATED WITH A STRENGTHENING SLY
FLOW/SHARPENING PRES GRADIENT BTWN THE DEPARTING HI AND A DISTURBANCE
APRCHG FM THE W...LINGERING LLVL DRY AIR SHOULD MAINTAIN VFR
CONDITIONS. AS THE WINDS INCRS ABV A SFC BASED STABLE LYR...MARGINAL
LLWS IS POSSIBLE AT THE TAF SITES. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 AM EDT SUN MAR 16 2014
LIGHT WINDS UNDER 20 KTS INTO TNGT ASSOCIATED WITH A PASSING HI PRES
CENTER WILL BECOME S AND INCREASE UP TO 20-25 KTS LATE TONIGHT INTO
MON UNDER THE SHARPENING PRES GRADIENT BETWEEN THE RETREATING HI TO
THE E AND A LO PRES DEVELOPING IN THE NCENTRAL PLAINS. ALTHOUGH THE
WINDS MAY DIMINISH LATER MON AND MON NIGHT AS THE HI CENTER SLIPS
FARTHER TO THE E AND THE GRADIENT WEAKENS...WINDS WILL BACK MORE TO
THE E AND INCREASE UP TO 25-30 KTS ON TUE AS THE PLAINS LO MOVES
TOWARD THE UPPER MIDWEST. THE FLOW WILL BACK TO THE NW UP TO 25 KTS
ON WED INTO THU ONCE THIS LOW SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
438 AM EDT SUN MAR 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM EDT SUN MAR 16 2014
00Z RAOBS/LATEST WV LOOP AND RUC ANALYSIS SHOW CONFLUENT NW FLOW ALF
OVER THE UPR GRT LKS BTWN PERSISTENT DEEP UPR TROF CENTERED NEAR
JAMES BAY AND MEAN UPR RDG OVER THE W. IN THE CORE OF THE COLD
AIRMASS THAT IS DOMINATING ERN CANADA AND THE NE CONUS...00Z H5/H85
TEMPS WERE AS LO AS -45C/-26C AT MOOSONEE AT THE S END OF JAMES BAY.
SFC HI PRES UNDER THE CONFLUENT UPR FLOW IS MOVING INTO NW MN EARLY
THIS MRNG. THE STEADY N WIND AHEAD OF THIS FEATURE IS ADVECTING
COLDER AIR INTO THE UPR LKS. DESPITE THE LLVL DRYNESS OF THE AIRMASS
DEPICTED ON THE 00Z INL/YPL RAOBS...WHERE THE PWAT WAS 0.05 AND 0.04
INCH RESPECTIVELY OR ONLY 25 PCT OF NORMAL...GENERAL ACYC NATURE OF
THE LLVL FLOW...AND THE EXTENSIVE ICE COVER ON LK SUP...SOME SCT LK
CLDS HAVE FORMED OVER THE NRN TIER OF THE U.P. BUT AT SOME OF THE
COLDER SPOTS OVER THE WRN INTERIOR...THE COMBINATION OF LIGHTER
WINDS AND THE VERY DRY AIR HAS CAUSED TEMPS TO FALL WELL BLO ZERO.
TO THE W OF THE SFC HI IN THE NRN PLAINS/SCNTRL CANADA...WAD BTWN
THE HI CENTER AND A SHRTV DROPPING SE OVER THE UPR RDG INTO SCNTRL
CANADA IS BRINGING LOTS OF CLDS AND SOME LGT SN.
MAIN FCST CONCERNS IN THE SHORT TERM ARE TEMPS FOR TODAY AND THEN
CLD TRENDS/IMPACT ON TEMPS TNGT AS WELL AS CHC FOR SN LATER TNGT
OVER THE W.
TODAY...ARCTIC HI PRES CENTER IS FCST TO DRIFT SLOWLY SE OVER UPR MI
TODAY AND TO NEAR TRAVERSE CITY BY 00Z MON. EXPECT ANY LK CLDS OVER
THE NRN TIER THIS MRNG TO DISSIPATE WITH THE ARRIVAL OF THE HI AND
DIURNAL HEATING. MIXING TO ABOUT H875 AS OBSVD UPSTREAM YDAY ON FCST
SDNGS YIELDS HI TEMPS REACHING THE 20-25 RANGE NEAR THE WI BORDER
AWAY FM ANY LK COOLING/ICE COVER.
TNGT...AS THE ARCTIC HI CENTER SHIFTS INTO SE ONTARIO BY 12Z MON AND
A SHRTWV SLIDING ESEWD IN THE WNW FLOW ALF ARND PERSISTENT UPR TROF
OVER QUEBEC MOVES TO NEAR LK WINNIPEG...DEEP...LARGER SCALE SSW
FLOW/ISENTROPIC ASCENT BEST SHOWN ON THE 280-290K SFCS /H8-6/ WL
RESULT IN INCRSG CLDS W-E. ALTHOUGH SOME LGT SN MAY REACH THE WRN
CWA LATE UNDER THE DEEPENING SATURATION/MORE IMPRESSIVE DEEP LYR
QVECTOR CNVGC/UPR DVGC IN EXIT REGION OF 100KT H3 JET MAX ASSOCIATED
WITH THE SHRTWV...TENACIOUS DRIER LLVL AIR ASSOCIATED WITH ONLY SLOW
MOVING SFC HI PRES OVER SE ONTARIO HELD IN PLACE BY NW FLOW ON THE
WRN FLANK OF QUEBEC TROF SHOULD KEEP MOST OF THE LAND CWA DRY THRU
THE NGT. MIN TEMPS WL BE LOWEST OVER THE E HALF CLOSER TO THE SFC
HI...WHERE WINDS WL BE LIGHTER AND WAD CLDS WL ARRIVE THE LATEST...
HELPING TO MAINTAIN PWAT AS LO AS 40-50 PCT OF NORMAL AT NEWBERRY
THRU 12Z MON. INCRSG CLDS AND DOWNSLOPE S WINDS OVER THE W NEAR LK
SUP WL GREATLY RESTRICT THE DIURNAL FALL OF TEMP THERE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 433 AM EDT SUN MAR 16 2014
FOCUS FOR THE UPCOMING WEEK IS ON LOW PRESSURE SYSTEM THAT LIFTS
ACROSS THE UPPER GREAT LAKES TUESDAY NIGHT INTO WEDNESDAY. BUT
FIRST THINGS FIRST AS SOME ACCUMULATING SNOW AND BLSN MAY OCCUR ON
MONDAY OVER AT LEAST NORTHWEST CWA.
SHORTWAVE CURRENTLY NOSING ACROSS CNTRL ALBERTA SHOWING UP WELL ON
WV LOOP. WAVE DIGS ESE TOWARD LK SUPERIOR REGION LATE TONIGHT AND
THEN SLIDES TO THE NORTH OF LK SUPERIOR IN ONTARIO BY MONDAY EVENING.
ALL THE MAIN MODELS SHOW A LOT OF MID LEVEL MOISTURE WITH LIFT
OCCURRING WITHIN THE DGZ. MAIN ISSUE IS LOW-LEVEL RH AS THERE IS
SIGNAL THAT DRY AIR ADVECTION WILL KEEP MUCH SNOW FM REACHING THE
EASTERN CWA. STRONGEST LIFT VIA THE WAVE AND WARM AIR ADVECTION AND
ISENTROPIC ASCENT ON 280-290K SFCS /H8-H6/ OCCURS OVER NW CWA...VCNTY
OF KEWEENAW PENINSULA. MIXING RATIOS TO 2G/KG AT H7 AND THE FOCUSED
LARGER SCALE FORCING POINT TO ACCUMULATING SNOW FM MID MORNING
THROUGH MID-LATE AFTN. IN ADDITION...GUSTY SOUTHERLY WINDS OVER 20
MPH MAY RESULT IN PATCHY BLSN AS WELL. POTENTIAL THAT BETTER
FORCING/LOW LEVEL MOISTURE MAY EVEN BUMP FARTHER NORTH AS ECMWF AND
NAM SHOWS...SO WILL NOT GO WITH LIKELY POPS QUITE YET...BUT WILL SHOW
HIGHER POP GRADIENT WITH HIGH CHANCES NW WITH SLIGHT CHANCES TO NO
MENTION OF POPS OVER SOUTH AND EAST CWA. TEMPS WILL SHOW A WARMING
TREND WITH UPR 20S WEST AND LOWER 20S EAST THOUGH GUSTY SOUTH WINDS
WILL PROVIDE A BITE TO THE WARMER TEMPS.
WARM AIR ADVECTION CONTINUES INTO MONDAY NIGHT AND TUESDAY AS PRIMARY
UPPER LEVEL TROUGH PUSHES ACROSS THE PLAINS. HINT THERE MAY BE A LEAD
SHORTWAVE AHEAD OF THE TROUGH COMING ACROSS UPR LAKES ON MONDAY
EVENING. ECMWF STRONGEST BUT GEM-NH AND EVEN GFS SHOW SOMETHING
SIMILAR. BUMPED POPS TO CHANCE IN THE EVENING FOR MAINLY WEST HALF.
LATER MONDAY NIGHT INTO TUESDAY...BETTER FORCING TAKES SHAPE TO THE
WEST MAINLY OVER MINNESOTA ALONG SFC-H85 TROUGH AXIS AND WITHIN
DEVELOPING AREA OF MID-LEVEL FGEN AND DIVERGENCE FM RIGHT ENTRANCE
JET FORCING. NET RESULT IS SHARPER EDGE OF MAIN AREA OF PRECIPITATION
BY TUESDAY. KEPT CHANCES BANKED OVER FAR WEST CWA...WHILE LOWER H85
RH SHOULD KEEP REST OF CWA MAINLY DRY ON TUESDAY...BARRING ANY MORE
SHORTWAVES WORKING THROUGH. SHIELD OF THICKER MID CLOUDS WILL KEEP
TEMPS IN THE LOW-MID 30S MOST AREAS...THOUGH A RUN INTO THE LOWER 40S
COULD OCCUR OVER WEST AND SOUTHWEST IF CLOUDS THIN OUT.
NOW ONTO THE PRIMARY SYSTEM OF THIS WEEK. SFC PATTERN AND MODEL
FORECAST H85 TEMPS SHOW WARM LAYER WILL BE FACTOR LATER TUESDAY
NIGHT INTO WEDNESDAY AS PLAINS UPPER LEVEL TROUGH BECOMES NEGATIVELY
TILTED AND AS 250MB DIVERGENCE INCREASES ATOP STRONG WARM AND MOIST
ADVECTION IN LOW-LEVELS. PERIOD OF MOST WIDESPREAD PRECIPITATION
WOULD BE FROM 09Z-18Z WEDNESDAY WITH COLD AIR ADVECTION AND CYCLONIC
FLOW ON BACKSIDE OF SFC-H85 LOW FURTHER BOOSTING PRECIP TOTALS ALONG
LK SUPERIOR 18Z WEDNESDAY THROUGH 06Z THURSDAY. SEVERAL INCHES OF
SNOW POSSIBLE WITH THE SYSTEM...BUT EXACTLY WHERE IS THE QUESTION.
CURRENTLY THE LINE BETWEEN SNOW AND MIXED PRECIPITATION /SLEET AND
FREEZING RAIN BOTH POSSIBLE BASED ON SOUNDINGS AND 1000-850MB AND
850-700MB THICKNESSES/ IS EXPECTED TO SET UP OVER CNTRL CWA. MODELS
HAVE SHOWN TYPICAL RUN TO RUN CONSISTENCY ISSUES AND ARE ALSO NOT
AGREEING WELL WITH EACH OTHER AND THIS WILL LIKELY CONTINUE INTO
EARLY THIS WEEK UNTIL THE SYSTEM /WHICH IS STILL COMING TOGETHER
OVER THE PACIFIC TO THE SOUTH OF ALASKA AND WEST OF BRITISH
COLUMBIA/ IS THOROUGHLY SAMPLED BY RAOB NETWORK AND THE MODELS
ULTIMATELY GET HANDLE ON WHERE THE SFC LOW WILL TRACK. LATEST MODELS
HAVE OVERALL TRENDED FARTHER EAST WITH SFC LOW AND COOLER WITH H85
TEMPS. DID NOT MAKE TOO MANY LARGE CHANGES TO PTYPE IN GRIDS.
FOLLOWING BLEND OF PREVIOUS MODELS LOCATION OF SFC LOW AND WARM
LAYER...KEPT MENTION OF ALL PTYPES IN FOR WEDNESDAY OVER THE EAST
CWA...WHILE MAINLY HAVE A MIX OF SNOW AND SLEET FOR CNTRL CWA...AND
ONLY SNOW IN THE WESTERN CWA.
BEYOND THE SYSTEM...LINGERING CYCLONIC FLOW IN WAKE OF THE SFC LOW
AND UPR LAKES IN VICINITY OF TROUGH AXIS ALOFT WILL LIKELY KEEP
PRECIP ON COLD SIDE OF SYSTEM PERSISTING WELL INTO WEDNESDAY NIGHT.
TURNED ALL PCPN BACK TO SNOW BY 00Z THURSDAY. THEN...SMALL CHANCES
FOR SNOW SHOWERS JUSTIFIED FOR AT LEAST FIRST PART OF THURSDAY WITH
HIGHER 1000-850MB RH AND WEAKLY CYCLONIC NW FLOW. FOR BOTH OF THESE
PERIODS...INCREASED POPS OVER WHAT MODEL CONSENSUS SHOWED.
SFC RIDGE AXIS EXPANDS FROM OHIO VALLEY ACROSS WESTERN GREAT LAKES
IN CONFLUENT FLOW ALOFT THURSDAY NIGHT INTO FRIDAY. ANY LINGERING
AFFECTS FM CLOUDS OR LIGHT LAKE EFFECT SHOULD WANE...ALLOWING FOR
TEMPS TO FALL OFF OVERNIGHT INTO FRIDAY MORNING. PREFERRED ECMWF
SHOWING MORE NW FLOW ALOFT VERSUS GFS WHICH TENDS TO FLATTEN THE
FLOW TOO QUICK. THUS...DISCOUNTED FARTHER NORTH QPF THAT GFS SHOWS
IMPACTING SOUTHERN CWA AS EARLY AS 06Z FRIDAY. SEEMS MUCH TOO QUICK
AND TOO FAR NORTH. LATEST ECMWF DID BUMP FARTHER NORTH WITH WAVE
MOVING THROUGH...SO KEPT CONSENSUS SMALL CHANCES FOR FAR SCNTRL CWA
FRIDAY INTO FRIDAY NIGHT.
REST OF EXTENDED FEATURES NW FLOW IN LOW-LEVELS BTWN DEVELOPING LOW
FOR THE NORTHEAST AND SFC HIGH CNTRL CANADA INTO THE PLAINS. 15MAR
12Z RUN OF ECMWF WAS SHOWING ANOTHER PUSH OF CHILLY AIR WITH H85
TEMPS NEARING -20C. THOUGH GEM-NH LOOKS LIKE THE GFS FRIDAY BEYOND
THAT IT ALSO SHOWS A COLD PLUNGE BACK ACROSS THE GREAT LAKES.
OVERALL NO MATTER WHAT MODEL IS FAVORED...NO SIGNIFCANT OR LASTING
WARM UPS ARE SEEN ANYTIME SOON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 122 AM EDT SUN MAR 16 2014
HIGH PRESSURE BUILDING IN NW OF THE LAKE SHOULD RESULT IN VFR
CONDITIONS THROUGH MUCH OF THE PERIOD AT ALL THE TAF SITES. LIGHT
LAKE BREEZE WINDS ARE EXPECTED TO DEVELOP BY LATE MORNING AT KCMX
AND KSAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 AM EDT SUN MAR 16 2014
LIGHT WINDS UNDER 20 KTS INTO TNGT ASSOCIATED WITH A PASSING HI PRES
CENTER WILL BECOME S AND INCREASE UP TO 20-25 KTS LATE TONIGHT INTO
MON UNDER THE SHARPENING PRES GRADIENT BETWEEN THE RETREATING HI TO
THE E AND A LO PRES DEVELOPING IN THE NCENTRAL PLAINS. ALTHOUGH THE
WINDS MAY DIMINISH LATER MON AND MON NIGHT AS THE HI CENTER SLIPS
FARTHER TO THE E AND THE GRADIENT WEAKENS...WINDS WILL BACK MORE TO
THE E AND INCREASE UP TO 25-30 KTS ON TUE AS THE PLAINS LO MOVES
TOWARD THE UPPER MIDWEST. THE FLOW WILL BACK TO THE NW UP TO 25 KTS
ON WED INTO THU ONCE THIS LOW SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 AM EDT SUN MAR 16 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM EDT SUN MAR 16 2014
00Z RAOBS/LATEST WV LOOP AND RUC ANALYSIS SHOW CONFLUENT NW FLOW ALF
OVER THE UPR GRT LKS BTWN PERSISTENT DEEP UPR TROF CENTERED NEAR
JAMES BAY AND MEAN UPR RDG OVER THE W. IN THE CORE OF THE COLD
AIRMASS THAT IS DOMINATING ERN CANADA AND THE NE CONUS...00Z H5/H85
TEMPS WERE AS LO AS -45C/-26C AT MOOSONEE AT THE S END OF JAMES BAY.
SFC HI PRES UNDER THE CONFLUENT UPR FLOW IS MOVING INTO NW MN EARLY
THIS MRNG. THE STEADY N WIND AHEAD OF THIS FEATURE IS ADVECTING
COLDER AIR INTO THE UPR LKS. DESPITE THE LLVL DRYNESS OF THE AIRMASS
DEPICTED ON THE 00Z INL/YPL RAOBS...WHERE THE PWAT WAS 0.05 AND 0.04
INCH RESPECTIVELY OR ONLY 25 PCT OF NORMAL...GENERAL ACYC NATURE OF
THE LLVL FLOW...AND THE EXTENSIVE ICE COVER ON LK SUP...SOME SCT LK
CLDS HAVE FORMED OVER THE NRN TIER OF THE U.P. BUT AT SOME OF THE
COLDER SPOTS OVER THE WRN INTERIOR...THE COMBINATION OF LIGHTER
WINDS AND THE VERY DRY AIR HAS CAUSED TEMPS TO FALL WELL BLO ZERO.
TO THE W OF THE SFC HI IN THE NRN PLAINS/SCNTRL CANADA...WAD BTWN
THE HI CENTER AND A SHRTV DROPPING SE OVER THE UPR RDG INTO SCNTRL
CANADA IS BRINGING LOTS OF CLDS AND SOME LGT SN.
MAIN FCST CONCERNS IN THE SHORT TERM ARE TEMPS FOR TODAY AND THEN
CLD TRENDS/IMPACT ON TEMPS TNGT AS WELL AS CHC FOR SN LATER TNGT
OVER THE W.
TODAY...ARCTIC HI PRES CENTER IS FCST TO DRIFT SLOWLY SE OVER UPR MI
TODAY AND TO NEAR TRAVERSE CITY BY 00Z MON. EXPECT ANY LK CLDS OVER
THE NRN TIER THIS MRNG TO DISSIPATE WITH THE ARRIVAL OF THE HI AND
DIURNAL HEATING. MIXING TO ABOUT H875 AS OBSVD UPSTREAM YDAY ON FCST
SDNGS YIELDS HI TEMPS REACHING THE 20-25 RANGE NEAR THE WI BORDER
AWAY FM ANY LK COOLING/ICE COVER.
TNGT...AS THE ARCTIC HI CENTER SHIFTS INTO SE ONTARIO BY 12Z MON AND
A SHRTWV SLIDING ESEWD IN THE WNW FLOW ALF ARND PERSISTENT UPR TROF
OVER QUEBEC MOVES TO NEAR LK WINNIPEG...DEEP...LARGER SCALE SSW
FLOW/ISENTROPIC ASCENT BEST SHOWN ON THE 280-290K SFCS /H8-6/ WL
RESULT IN INCRSG CLDS W-E. ALTHOUGH SOME LGT SN MAY REACH THE WRN
CWA LATE UNDER THE DEEPENING SATURATION/MORE IMPRESSIVE DEEP LYR
QVECTOR CNVGC/UPR DVGC IN EXIT REGION OF 100KT H3 JET MAX ASSOCIATED
WITH THE SHRTWV...TENACIOUS DRIER LLVL AIR ASSOCIATED WITH ONLY SLOW
MOVING SFC HI PRES OVER SE ONTARIO HELD IN PLACE BY NW FLOW ON THE
WRN FLANK OF QUEBEC TROF SHOULD KEEP MOST OF THE LAND CWA DRY THRU
THE NGT. MIN TEMPS WL BE LOWEST OVER THE E HALF CLOSER TO THE SFC
HI...WHERE WINDS WL BE LIGHTER AND WAD CLDS WL ARRIVE THE LATEST...
HELPING TO MAINTAIN PWAT AS LO AS 40-50 PCT OF NORMAL AT NEWBERRY
THRU 12Z MON. INCRSG CLDS AND DOWNSLOPE S WINDS OVER THE W NEAR LK
SUP WL GREATLY RESTRICT THE DIURNAL FALL OF TEMP THERE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 258 PM EDT SAT MAR 15 2014
MAIN FORECAST CONCERNS ARE IN THE MIDDLE OF THE COMING WEEK AS A
SYSTEM MAY IMPACT THE CWA...POSSIBLY BRINGING MIXED PRECIP AND SOME
SIGNIFICANT SNOWFALL AMOUNTS TO PARTS OF THE CWA. OTHERWISE...ONLY
MINOR PRECIP WITH MINIMAL IMPACTS IS EXPECTED.
FOR THE MID WEEK SYSTEM...THERE IS A LOT OF UNCERTAINTY AS MODEL RUN
TO RUN CONTINUITY HAS BEEN POOR FOR MOST MODELS AND MODEL AGREEMENT
HAS ONLY BEEN FAIR. THE POOR CONTINUITY AND UNCERTAINTY IS CERTAINLY
UNDERSTANDABLE GIVEN THAT THE UPPER LEVEL ENERGY FOR THE SYSTEM WILL
BE EJECTING OUT OF A TROUGH CURRENTLY STRETCHING S OF AN UPPER LOW
OVER SW AK. THE LAST COUPLE OF RUNS OF MODELS HAVE COME INTO BETTER
MODEL TO MODEL AGREEMENT...WHICH IS TYPICAL FOR WHERE THE ENERGY IS
CURRENTLY LOCATED...BUT WOULD NOT BE SURPRISE TO SEE MODEL SPREAD
INCREASE SIGNIFICANTLY ONCE THE SYSTEM MOVES INTO THE BETTER
OBSERVATION NETWORK OF THE PACIFIC NW CONUS ON MON. IN A TYPICAL
SITUATION WITH THIS TYPE OF SYSTEM...SHOULD START SEEING BETTER
MODEL AGREEMENT AND HAVE GREATER CONFIDENCE MON NIGHT OR TUE AS THE
SYSTEM MOVES LEEWARD OF THE ROCKIES...ESPECIALLY SINCE THE SHORTWAVE
WILL BE MOVING INTO A STRONG RIDGE UP UNTIL THIS POINT...LEADING TO
ADDITIONAL UNCERTAINTY WITH HOW WELL IT DOES AFTER INTERACTING WITH
THE RIDGE. MODELS SHOW THE SHORTWAVE DEEPENING AND BECOMING
NEGATIVELY TILTED AFTER LEEWARD CYCLOGENESIS OCCURS E OF THE ROCKIES
AND NRN/SRN JET STREAM INTERACTION OCCURS ON THE S SIDE OF THE UPPER
TROUGH. EXACTLY WHERE AND TO WHAT MAGNITUDE THE LOW DEEPENS IS LESS
AGREED TO BETWEEN THE MODELS AND WILL LIKELY CHANGE IN FUTURE RUNS
ANYWAY. MODELS THEN SHOW THE LOW CLOSING OFF OVER OR NEAR THE CWA
SOMETIME WED/WED NIGHT. THE WARM SECTOR WILL BE WARM ENOUGH FOR
MIXED PRECIP OVER AT LEAST THE SERN TWO THIRDS OF THE CWA GIVEN
CURRENT MODEL DEPICTIONS AND MORE SNOW OVER THE NW THIRD.
AGAIN...THESE DETAILS WILL LIKELY CHANGE OVER THE NEXT FEW DAYS.
THAT BEING SAID...DID NOT FIND ANY GOOD REASONS TO CHANGE THE
PREVIOUS FORECAST THAT HAD MIXED PRECIP OVER THE AFOREMENTIONED
FAVORED AREAS. TO THE W/NW OF THE LOW TRACK...SIGNIFICANT SNOWFALL
AMOUNTS ARE POSSIBLE BUT DETAILS ARE STILL SKETCHY. DEFINITELY A
TRICKY SYSTEM THAT WILL HAVE TO BE FINE TUNED SIGNIFICANTLY OVER THE
COMING DAYS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 122 AM EDT SUN MAR 16 2014
HIGH PRESSURE BUILDING IN NW OF THE LAKE SHOULD RESULT IN VFR
CONDITIONS THROUGH MUCH OF THE PERIOD AT ALL THE TAF SITES. LIGHT
LAKE BREEZE WINDS ARE EXPECTED TO DEVELOP BY LATE MORNING AT KCMX
AND KSAW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 348 AM EDT SUN MAR 16 2014
LIGHT WINDS UNDER 20 KTS INTO TNGT ASSOCIATED WITH A PASSING HI PRES
CENTER WILL BECOME S AND INCREASE UP TO 20-25 KTS LATE TONIGHT INTO
MON UNDER THE SHARPENING PRES GRADIENT BETWEEN THE RETREATING HI TO
THE E AND A LO PRES DEVELOPING IN THE NCENTRAL PLAINS. ALTHOUGH THE
WINDS MAY DIMINISH LATER MON AND MON NIGHT AS THE HI CENTER SLIPS
FARTHER TO THE E AND THE GRADIENT WEAKENS...WINDS WILL BACK MORE TO
THE E AND INCREASE UP TO 25-30 KTS ON TUE AS THE PLAINS LO MOVES
TOWARD THE UPPER MIDWEST. THE FLOW WILL BACK TO THE NW UP TO 25 KTS
ON WED INTO THU ONCE THIS LOW SHIFTS TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS DULUTH MN
937 PM CDT MON MAR 17 2014
.UPDATE...
ISSUED AT 937 PM CDT MON MAR 17 2014
LITTLE OCCURRING IN WAY OF PRECIPITATION AS OF MID EVENING AND WE
UPDATED TO LOWER POPS UNTIL AROUND OR AFTER 06Z. THE 00Z NAM IS IN
THROUGH AT LEAST WEDNESDAY AND IS LIGHTER WITH ITS SNOWFALL
FORECAST.
AT 02Z...THE SURFACE LOW WAS LOCATED IN SOUTH-CENTRAL SOUTH
DAKOTA. AN AREA OF MID LEVEL FGEN FORCING WAS ANALYZED ALONG THE
NORTH AND SOUTH DAKOTA BORDER PER THE SPC MESOANALYSIS SITE AND
THE NAM WAS DEPICTING THIS AS WELL. THIS WILL BE THE FOCUS FOR
SNOW DEVELOPMENT OVERNIGHT AND THE HIGH RES MODELS AND LATEST NAM
SHOW STRENGTHENING MID LEVEL FGEN INTO OUR SOUTHERN/CENTRAL ZONES
AROUND OR AFTER 06Z THROUGH TUESDAY AFTERNOON. THE 00Z NAM SHOWS A
NARROW BAND OF SNOW DEVELOPING BETWEEN 06Z-12Z FROM THE BRAINERD
LAKES REGION INTO FAR NORTHERN WISCONSIN...THEN LIFTS IT NORTH
DURING THE MORNING/AFTERNOON HOURS. CONFIDENCE IN A WIDESPREAD
HEAVY SNOW AREA IS NOT AS HIGH AS EARLIER...BUT IT IS THERE FOR A
NARROWER BAND BASED ON EXPECTED MID LEVEL FGEN. IT WILL BE A
SHORTER TERM FORECAST CHALLENGE IN DEFINING THE EXACT PLACEMENT OF
THIS HEAVIER SNOWBAND. WE DID NOT MAKE ANY MAJOR CHANGES TO THE
GOING FORECAST OTHER THAN WHAT WAS DISCUSSED EARLIER ABOUT DELAYING
SOME OF THE STARTING TIMES OF THE NORTHERN WARNINGS/ADVISORIES. WE
NEED TO WAIT FOR THE REST OF THE MODELS AND FOR THIS BAND TO TAKE
SHAPE BEFORE MAKING ANY SIGNIFICANT CHANGES TO THE SNOWFALL
FORECAST.
UPDATE ISSUED AT 648 PM CDT MON MAR 17 2014
RADAR SHOWS THE STRONGER RETURNS OVER WASHBURN/SAWYER/PRICE
COUNTIES HAVE DIMINISHED EARLY THIS EVENING...AND THE VSBY AT KHYR
HAS RISEN TO 10SM BUT KPBH WAS STILL 1.25SM. MUCH OF THE SNOW WILL
END FOR A TIME OVER OUR CWA THIS EVENING. THE 4KM WRF/NAM/GFS
FORECAST A BAND OF FGEN FORCED PRECIP OVER ABOUT THE SOUTHERN HALF
OF THE NORTHLAND BY 12Z TUESDAY. WE ARE LEANING TOWARD MAKING SOME
ADJUSTMENTS TO OUR HEADLINES...MAINLY DELAYING THE ONSET OVER OUR
NORTHERN MINNESOTA ZONES. WE ALSO ARE LEANING TOWARD CHANGING THE
WATCH OVER PRICE COUNTY TO AN ADVISORY...AND STARTING IT LATER
TONIGHT. NO OTHER SIGNIFICANT CHANGES WILL BE MADE TO THE GRIDS AT
THIS TIME...AS LITTLE NEW DATA HAS ARRIVED AT THIS POINT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY AFTERNOON)
ISSUED AT 355 PM CDT MON MAR 17 2014
LARGE WINTER STORM IMPACTING THE NORTHLAND LATE TONIGHT THROUGH
TUESDAY REMAINS THE MAIN FOCUS OF ATTENTION IN THE SHORT TERM THIS
AFTERNOON. WINTER HEADLINES REMAIN IN EFFECT FOR MUCH OF NE MN AND
NW WI DURING THIS TIME.
DEEPENING UPPER TROUGH CONTINUES TO BARREL THROUGH THE NRN ROCKIES
THIS AFTERNOON AS A SFC LOW DEVELOPS OVER THE FRONT RANGE AND A
WARM FRONT EXTENDS TO THE EAST. ALREADY SEEING WAA SNOW SHOWERS
DEVELOP ACROSS CENTRAL MN. THERE WILL ALSO BE SOME SLEET OR LIGHT
RAIN MIXED IN WITH THESE EVENING SHOWERS AROUND THE BRAINERD LAKES
AREA. NO SIGNIFICANT ICING IS EXPECTED. LIGHT SNOW SHOWERS WILL
PERSIST ALONG THE NORTH SHORE AS E/SE WINDS ACROSS WRN LAKE
SUPERIOR CONTINUE TO PUMP IN MOISTURE TO LAKE AND COOK COUNTIES.
THE WAA AHEAD OF THE LOW WILL CONTINUE TONIGHT AND INTO TUE
MORNING AS A BAND OF STRONG MID-LVL F-GEN INTENSIFIES AND PIVOTS
ALONG THE DEFORMATION ZONE AS THE SFC LOW MOVES FROM OMAHA TO
NRN LOWER MICHIGAN FROM TUE AFTERNOON THROUGH WED MORNING. THERE
ARE STILL SIGNIFICANT DIFFERENCES IN MODEL QPF/SNOW AMT OUTPUT AND
WHERE THE HEAVIEST SWATH OF SNOW WILL DEVELOP. THE CONSENSUS
HOWEVER REMAINS FROM AROUND LAKE MILLE LACS TO DULUTH AND ALONG
THE NORTH AND SOUTH SHORES. THE ENHANCEMENT FROM LAKE SUPERIOR AND
THE TERRAIN WILL ALLOW SNOWFALL AMTS TO BE SLIGHTLY HIGHER FROM
TWO HARBORS TO GRAND MARAIS...AND ALSO FROM SOUTH RANGE TO THE
GOGEBIC RANGE IN WI. THERE WILL LIKELY BE A BROAD AREA OF 8-10
INCHES FROM SW TO NE...AND HIGHER AMTS UP TO 14 INCHES ALONG/NEAR
THE ELEVATED TERRAIN. THE PERSISTENT SNOW IN NW WI FOR INLAND
LOCATIONS INCLUDING HAYWARD SPOONER AND SIREN WILL ALSO PRODUCE
MORE THAN 8 INCHES IN 24 HOURS...SO UPGRADED BURNETT WASHBURN AND
SAWYER TO A WINTER STORM WARNING. THERE IS STILL SOME UNCERTAINTY
WITH PRICE COUNTY AS THEY WILL REMAIN IN THE DRY/WARM SLOT AS THE
SYSTEM WRAPS UP DURING THE DAY TUESDAY. HOWEVER THEY SHOULD
EVENTUALLY BE ABLE TO PICK UP MORE THAN 6 INCHES FAIRLY QUICKLY.
DECIDED TO GO WITH A WATCH FOR PRICE COUNTY AT THIS TIME...WITH
THE NOTION OF UPGRADING THIS EVENING OR TONIGHT TO AN ADVSY OR
WARNING.
A STRING OF COUNTIES TO THE WEST...INCLUDING NRN CASS ITASCA AND
NRN ST. LOUIS HAVE BEEN PLACED IN A WINTER WX ADVISORY. THERE WILL
LIKELY BE A SHARP GRADIENT OF SNOWFALL WHERE WESTERN SECTIONS
COULD ONLY SEE 1 TO 4 INCHES AND THE EASTERN HALF OF THE COUNTIES
COULD PICK UP CLOSER TO 5 OR 6 INCHES THROUGH THE DURATION OF THE
EVENT. ALSO...THE RECENT TRENDS OF THE SFC LOW CONTINUE TO BE TO
THE EAST AND SOUTHEAST. SO THIS GIVES MORE CONFIDENCE THAT THESE
WRN LOCATIONS WILL SEE LESSER SNOW AMTS.
BLOWING SNOW COULD ALSO BE OF CONCERN WITH THIS SYSTEM AS THE LOW
LIFTS TO THE E/NE AND HIGH PRESSURE BUILDS IN FROM THE WEST. A
TIGHT PRES GRADIENT WILL SET UP AND ALLOW N/NE WINDS TO STRENGTHEN
ACROSS THE REGION...ESPECIALLY OVER WRN LAKE SUPERIOR AND ALONG
THE IMMEDIATE LAKESHORE AREAS. THE TWIN PORTS WILL LIKELY SEE
GUSTY WINDS 25 TO 30 MPH...AND MAY NEED TO ADD BLOWING SNOW TO
THE FORECAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 PM CDT MON MAR 17 2014
THE WINTER STORM WILL CONTINUE ACROSS THE AREA TUESDAY NIGHT AND
GRADUALLY PULL EAST OF THE REGION ON WEDNESDAY. ACCUMULATING SNOW IS
STILL EXPECTED TUESDAY NIGHT AND WEDNESDAY ACROSS MUCH OF THE AREA
WITH THE FOCUS SHIFTING TO THE SOUTH SHORE BY WEDNESDAY AND
WEDNESDAY NIGHT. TEMPERATURES WILL GENERALLY BE IN THE 30S FROM
WEDNESDAY THROUGH FRIDAY FOR DAYTIME HIGHS AS THE UPPER LEVEL FLOW
GENERALLY FLATTENS A BIT DURING THAT TIME. ANOTHER SHORTWAVE WILL
MOVE INTO THE REGION ON FRIDAY AND FRIDAY NIGHT...AND SHOULD BRING
ANOTHER ROUND OF SNOW TO THE REGION. THE BEST BET FOR SOME LIGHT
ACCUMULATION AT THIS POINT APPEARS TO BE IN THE SOUTHERN PORTIONS OF
THE CWA. MAY NEED TO INCREASE POPS AS THIS EVENT NEARS. A STRONG
COLD FRONT WILL MOVE IN BEHIND THE SYSTEM WITH HIGH TEMPERATURES
DROPPING TO THE 20S FOR THE WEEKEND. THE BELOW NORMAL TEMPERATURES
WILL CONTINUE INTO THE FIRST PART OF NEXT WEEK AS WELL. ANOTHER
CLIPPER TYPE SYSTEM MAY BRING SOME LIGHT SNOW TO THE REGION BY
MONDAY AS WELL...BUT LOOKS GENERALLY LIGHT AT THIS POINT. SO IN
SHORT WE SHOULD START OUT WITH NEAR NORMAL TEMPERATURES AND A WINTER
STORM...FOLLOWED BY COLDER AND GENERALLY DRIER AIR FOR THE REMAINDER
OF THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 648 PM CDT MON MAR 17 2014
VARIABLE CONDITIONS COVERED THE NORTHLAND EARLY THIS
EVENING...WITH MVFR CEILINGS TO VFR. KBRD HAS RECENTLY GONE TO VFR
AND THE RAP WAS DOING AN OK JOB OF DEPICTING THAT AND CONTINUES TO
SHOW MAINLY VFR CONDITIONS OVER OUR SOUTHERN ZONES UNTIL LATER
TONIGHT. KHIB/KDLH/KINL SHOULD CONTINUE TO SEE MVFR
CEILINGS...ALTHOUGH A PERIOD OF VFR CAN NOT BE RULED OUT EITHER.
AS WINDS BACK TO MORE EASTERLY...THE CHANCES FOR MVFR OR LOWER
CEILINGS SHOULD INCREASE.
MOST OF THE GUIDANCE SUGGESTS A BREAK IN THE ACTION REGARDING
PRECIPITATION COVERAGE THROUGH MUCH OF THE EVENING...WITH A WEST TO
EAST BAND OF PRECIPITATION DEVELOPING LATER TONIGHT FROM THE
BRAINERD LAKES EAST-NORTHEAST TOWARD THE TWIN PORTS AND ACROSS
NORTHERN WISCONSIN. SNOW AND LOWERING VSBYS/CEILINGS WILL BECOME
MORE WIDESPREAD THROUGH THE DAY TUESDAY FOR MOST AREAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 21 28 21 31 / 80 90 90 50
INL 16 31 18 31 / 10 20 40 20
BRD 24 30 22 33 / 90 100 60 20
HYR 22 33 23 33 / 70 80 90 70
ASX 22 32 24 33 / 80 90 90 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER STORM WARNING FROM 7 AM TUESDAY TO 6 PM CDT WEDNESDAY FOR
MNZ012-020-021.
WINTER WEATHER ADVISORY FROM 7 AM TUESDAY TO 11 AM CDT WEDNESDAY
FOR MNZ011-018-025-026.
WINTER STORM WARNING UNTIL 11 AM CDT WEDNESDAY FOR MNZ033>038.
WINTER STORM WARNING FROM 7 AM TUESDAY TO 11 AM CDT WEDNESDAY
FOR MNZ019.
WI...WINTER STORM WARNING UNTIL 6 PM CDT WEDNESDAY FOR WIZ001>004-
006>008.
WINTER WEATHER ADVISORY UNTIL 6 PM CDT WEDNESDAY FOR WIZ009.
LS...NONE.
&&
$$
UPDATE...MELDE
SHORT TERM...BJT
LONG TERM...DAP
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
648 PM CDT MON MAR 17 2014
.UPDATE...
ISSUED AT 648 PM CDT MON MAR 17 2014
RADAR SHOWS THE STRONGER RETURNS OVER WASHBURN/SAWYER/PRICE
COUNTIES HAVE DIMINISHED EARLY THIS EVENING...AND THE VSBY AT KHYR
HAS RISEN TO 10SM BUT KPBH WAS STILL 1.25SM. MUCH OF THE SNOW WILL
END FOR A TIME OVER OUR CWA THIS EVENING. THE 4KM WRF/NAM/GFS
FORECAST A BAND OF FGEN FORCED PRECIP OVER ABOUT THE SOUTHERN HALF
OF THE NORTHLAND BY 12Z TUESDAY. WE ARE LEANING TOWARD MAKING SOME
ADJUSTMENTS TO OUR HEADLINES...MAINLY DELAYING THE ONSET OVER OUR
NORTHERN MINNESOTA ZONES. WE ALSO ARE LEANING TOWARD CHANGING THE
WATCH OVER PRICE COUNTY TO AN ADVISORY...AND STARTING IT LATER
TONIGHT. NO OTHER SIGNIFICANT CHANGES WILL BE MADE TO THE GRIDS AT
THIS TIME...AS LITTLE NEW DATA HAS ARRIVED AT THIS POINT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY AFTERNOON)
ISSUED AT 355 PM CDT MON MAR 17 2014
LARGE WINTER STORM IMPACTING THE NORTHLAND LATE TONIGHT THROUGH
TUESDAY REMAINS THE MAIN FOCUS OF ATTENTION IN THE SHORT TERM THIS
AFTERNOON. WINTER HEADLINES REMAIN IN EFFECT FOR MUCH OF NE MN AND
NW WI DURING THIS TIME.
DEEPENING UPPER TROUGH CONTINUES TO BARREL THROUGH THE NRN ROCKIES
THIS AFTERNOON AS A SFC LOW DEVELOPS OVER THE FRONT RANGE AND A
WARM FRONT EXTENDS TO THE EAST. ALREADY SEEING WAA SNOW SHOWERS
DEVELOP ACROSS CENTRAL MN. THERE WILL ALSO BE SOME SLEET OR LIGHT
RAIN MIXED IN WITH THESE EVENING SHOWERS AROUND THE BRAINERD LAKES
AREA. NO SIGNIFICANT ICING IS EXPECTED. LIGHT SNOW SHOWERS WILL
PERSIST ALONG THE NORTH SHORE AS E/SE WINDS ACROSS WRN LAKE
SUPERIOR CONTINUE TO PUMP IN MOISTURE TO LAKE AND COOK COUNTIES.
THE WAA AHEAD OF THE LOW WILL CONTINUE TONIGHT AND INTO TUE
MORNING AS A BAND OF STRONG MID-LVL F-GEN INTENSIFIES AND PIVOTS
ALONG THE DEFORMATION ZONE AS THE SFC LOW MOVES FROM OMAHA TO
NRN LOWER MICHIGAN FROM TUE AFTERNOON THROUGH WED MORNING. THERE
ARE STILL SIGNIFICANT DIFFERENCES IN MODEL QPF/SNOW AMT OUTPUT AND
WHERE THE HEAVIEST SWATH OF SNOW WILL DEVELOP. THE CONSENSUS
HOWEVER REMAINS FROM AROUND LAKE MILLE LACS TO DULUTH AND ALONG
THE NORTH AND SOUTH SHORES. THE ENHANCEMENT FROM LAKE SUPERIOR AND
THE TERRAIN WILL ALLOW SNOWFALL AMTS TO BE SLIGHTLY HIGHER FROM
TWO HARBORS TO GRAND MARAIS...AND ALSO FROM SOUTH RANGE TO THE
GOGEBIC RANGE IN WI. THERE WILL LIKELY BE A BROAD AREA OF 8-10
INCHES FROM SW TO NE...AND HIGHER AMTS UP TO 14 INCHES ALONG/NEAR
THE ELEVATED TERRAIN. THE PERSISTENT SNOW IN NW WI FOR INLAND
LOCATIONS INCLUDING HAYWARD SPOONER AND SIREN WILL ALSO PRODUCE
MORE THAN 8 INCHES IN 24 HOURS...SO UPGRADED BURNETT WASHBURN AND
SAWYER TO A WINTER STORM WARNING. THERE IS STILL SOME UNCERTAINTY
WITH PRICE COUNTY AS THEY WILL REMAIN IN THE DRY/WARM SLOT AS THE
SYSTEM WRAPS UP DURING THE DAY TUESDAY. HOWEVER THEY SHOULD
EVENTUALLY BE ABLE TO PICK UP MORE THAN 6 INCHES FAIRLY QUICKLY.
DECIDED TO GO WITH A WATCH FOR PRICE COUNTY AT THIS TIME...WITH
THE NOTION OF UPGRADING THIS EVENING OR TONIGHT TO AN ADVSY OR
WARNING.
A STRING OF COUNTIES TO THE WEST...INCLUDING NRN CASS ITASCA AND
NRN ST. LOUIS HAVE BEEN PLACED IN A WINTER WX ADVISORY. THERE WILL
LIKELY BE A SHARP GRADIENT OF SNOWFALL WHERE WESTERN SECTIONS
COULD ONLY SEE 1 TO 4 INCHES AND THE EASTERN HALF OF THE COUNTIES
COULD PICK UP CLOSER TO 5 OR 6 INCHES THROUGH THE DURATION OF THE
EVENT. ALSO...THE RECENT TRENDS OF THE SFC LOW CONTINUE TO BE TO
THE EAST AND SOUTHEAST. SO THIS GIVES MORE CONFIDENCE THAT THESE
WRN LOCATIONS WILL SEE LESSER SNOW AMTS.
BLOWING SNOW COULD ALSO BE OF CONCERN WITH THIS SYSTEM AS THE LOW
LIFTS TO THE E/NE AND HIGH PRESSURE BUILDS IN FROM THE WEST. A
TIGHT PRES GRADIENT WILL SET UP AND ALLOW N/NE WINDS TO STRENGTHEN
ACROSS THE REGION...ESPECIALLY OVER WRN LAKE SUPERIOR AND ALONG
THE IMMEDIATE LAKESHORE AREAS. THE TWIN PORTS WILL LIKELY SEE
GUSTY WINDS 25 TO 30 MPH...AND MAY NEED TO ADD BLOWING SNOW TO
THE FORECAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 PM CDT MON MAR 17 2014
THE WINTER STORM WILL CONTINUE ACROSS THE AREA TUESDAY NIGHT AND
GRADUALLY PULL EAST OF THE REGION ON WEDNESDAY. ACCUMULATING SNOW IS
STILL EXPECTED TUESDAY NIGHT AND WEDNESDAY ACROSS MUCH OF THE AREA
WITH THE FOCUS SHIFTING TO THE SOUTH SHORE BY WEDNESDAY AND
WEDNESDAY NIGHT. TEMPERATURES WILL GENERALLY BE IN THE 30S FROM
WEDNESDAY THROUGH FRIDAY FOR DAYTIME HIGHS AS THE UPPER LEVEL FLOW
GENERALLY FLATTENS A BIT DURING THAT TIME. ANOTHER SHORTWAVE WILL
MOVE INTO THE REGION ON FRIDAY AND FRIDAY NIGHT...AND SHOULD BRING
ANOTHER ROUND OF SNOW TO THE REGION. THE BEST BET FOR SOME LIGHT
ACCUMULATION AT THIS POINT APPEARS TO BE IN THE SOUTHERN PORTIONS OF
THE CWA. MAY NEED TO INCREASE POPS AS THIS EVENT NEARS. A STRONG
COLD FRONT WILL MOVE IN BEHIND THE SYSTEM WITH HIGH TEMPERATURES
DROPPING TO THE 20S FOR THE WEEKEND. THE BELOW NORMAL TEMPERATURES
WILL CONTINUE INTO THE FIRST PART OF NEXT WEEK AS WELL. ANOTHER
CLIPPER TYPE SYSTEM MAY BRING SOME LIGHT SNOW TO THE REGION BY
MONDAY AS WELL...BUT LOOKS GENERALLY LIGHT AT THIS POINT. SO IN
SHORT WE SHOULD START OUT WITH NEAR NORMAL TEMPERATURES AND A WINTER
STORM...FOLLOWED BY COLDER AND GENERALLY DRIER AIR FOR THE REMAINDER
OF THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 648 PM CDT MON MAR 17 2014
VARIABLE CONDITIONS COVERED THE NORTHLAND EARLY THIS
EVENING...WITH MVFR CEILINGS TO VFR. KBRD HAS RECENTLY GONE TO VFR
AND THE RAP WAS DOING AN OK JOB OF DEPICTING THAT AND CONTINUES TO
SHOW MAINLY VFR CONDITIONS OVER OUR SOUTHERN ZONES UNTIL LATER
TONIGHT. KHIB/KDLH/KINL SHOULD CONTINUE TO SEE MVFR
CEILINGS...ALTHOUGH A PERIOD OF VFR CAN NOT BE RULED OUT EITHER.
AS WINDS BACK TO MORE EASTERLY...THE CHANCES FOR MVFR OR LOWER
CEILINGS SHOULD INCREASE.
MOST OF THE GUIDANCE SUGGESTS A BREAK IN THE ACTION REGARDING
PRECIPITATION COVERAGE THROUGH MUCH OF THE EVENING...WITH A WEST TO
EAST BAND OF PRECIPITATION DEVELOPING LATER TONIGHT FROM THE
BRAINERD LAKES EAST-NORTHEAST TOWARD THE TWIN PORTS AND ACROSS
NORTHERN WISCONSIN. SNOW AND LOWERING VSBYS/CEILINGS WILL BECOME
MORE WIDESPREAD THROUGH THE DAY TUESDAY FOR MOST AREAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 21 28 21 31 / 80 90 90 50
INL 16 31 18 31 / 20 20 40 20
BRD 24 30 22 33 / 90 100 60 20
HYR 22 33 23 33 / 80 80 90 70
ASX 22 32 24 33 / 90 90 90 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 PM CDT WEDNESDAY
FOR MNZ012-019>021-033>038.
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CDT
WEDNESDAY FOR MNZ011-018-025-026.
WI...WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 PM CDT WEDNESDAY
FOR WIZ001>004-006>008.
WINTER STORM WATCH FROM MIDNIGHT CDT TONIGHT THROUGH WEDNESDAY
AFTERNOON FOR WIZ009.
LS...NONE.
&&
$$
UPDATE...MELDE
SHORT TERM...BJT
LONG TERM...DAP
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
825 PM MDT MON MAR 17 2014
.UPDATE...
A STRONG DEEP NORTHERLY FLOW UP TO 500MB PLUS AN UNSTABLE AIRMASS
HAVE MANAGED TO PRODUCE NEAR WHITEOUT CONDITIONS AT TIMES IN THE
BEARTOOTH AND RED LODGE FOOTHILLS. THE BLOWING HAS MADE IT HARD
FOR OBSERVERS TO ESTIMATE SNOWFALL SO FAR...BUT 2-3 INCHES AND
SOME LOCAL AMOUNTS TO 4 INCHES SEEM TO BE THE NORM. RADAR AND
SATELLITE SHOWS MORE MOISTURE STREAMING INTO THE FOOTHILLS THROUGH
THE MID EVENING HOURS SO HAVE UPGRADED THE ADVISORIES TO WARNINGS.
CROSS SECTIONS FROM THE NEW NAM ARE A CONCERN AS WELL AS THEY SHOW
THE DEEP UPSLOPE LASTING THROUGH THE ENTIRE NIGHT. THUS...NEXT
SHIFT MAY NEED TO EXTEND THE WARNING PAST THE END PERIOD OF 06Z.
OTHER CONCERN FOR THE EVENING IS HOW WELL ADVISORIES IN SE
SECTIONS WILL VERIFY. WARM AIR MAY BE ENTRAINED FROM THE NORTH TO
PREVENT A SOLID TURN OVER TO SNOW UNTIL LATE TONIGHT...THUS
LIMITING SNOWFALL ACCUMULATIONS. THIS WILL BE A CLOSE CALL SO DOES
NOT SEEM PRUDENT TO CHANGE ANYTHING AT THIS POINT FOR THE SE
ZONES. BT
&&
.SHORT TERM...VALID FOR TUE AND WED...
UNSTABLE AIRMASS OVER THE REGION WITH SURFACE LOW PRESSURE MOVING
SOUTHEASTWARD ACROSS WESTERN SOUTH DAKOTA. ONE FRONT ALREADY
PULLED THROUGH THE AREA AND A SECOND ONE PUSHING INTO THE NORTHERN
ZONES AS A DISTURBANCE MOVES THROUGH CENTRAL MONTANA. RADAR SHOWS
SHOWER ACTIVITIES WITH ACTIVITY STRONGEST ALONG THE MOUNTAINS AND
FOOTHILLS. FORECAST GETS QUIET FOR TUESDAY AND WEDNESDAY SO ALL
WEATHER CONCERNS CONFINED TO MAINLY THE NEXT 12 HOURS.
AREAS FOR GREATEST SNOWFALL TONIGHT WILL BE WHERE UPSLOPE HAS A
CHANCE TO WORK WITH THE INSTABILITY. LIGHTNING OBSERVED BY HAVRE
SO COLDEST AIR ALOFT IS NORTH OF THE AREA AND LAPSE RATE PROGS
SHOW WESTERN ZONES DESTABILIZE DURING THE EVENING HOURS. LAPSE
RATES ARE NOT EXPECTED TO BE AS STEEP IN SOUTHEAST MONTANA SO
EXPECT PRECIPITATION TO BE FAVORED IN A WRAP AROUND FLOW ON THE
NORTH SIDE OF THE SOUTH DAKOTA LOW PRESSURE. SNOW ADVISORIES FOR
LIVINGSTON AND PARADISE VALLEY LOOK GOOD ALONG WITH THE FOOTHILLS
AND BIG HORN MOUNTAINS. SOUTHEAST MONTANA MAY STRUGGLE AS
TEMPERATURES ARE STILL MILD AND BEST BAND OF PRECIPITATION DIVES
QUICKLY SOUTHWARD DURING THE EVENING. WINDS ARE STARTING TO PICK
UP OVER NORTH CENTRAL MONTANA AND EXPECT WIND TO INCREASE FROM THE
NORTHWEST OVER THE NEXT FEW HOURS. ONE AREA THAT WILL LIKELY SEE
LOCAL PROBLEMS IS JUDITH GAP THOUGH BURST OF SNOW WILL BE SHORTER.
FOR AREAS NOT COVERED BY ADVISORIES JUST THINK WEATHER IS
TRAVELING SO FAST THAT 90 MINUTES OF HEAVY SNOW SHOWERS WILL BE
THE GREATEST IMPACT AND ROAD SURFACES MAY BE ABOVE FREEZING FOR
MOST OF THE THAT TIME.
SNOWFALL CHANCES WILL RAPIDLY DECREASE OVERNIGHT AS SHORTWAVE
RIDGING PUSHES DEEPEST MOISTURE SOUTH OF THE AREA. RUC MODEL
CONTINUES TO TREND THE WRAP AROUND MOISTURE SOUTH OF THE REGION
BUT SUSPECT BIG HORN MOUNTAINS AND SHERIDAN COUNTY STAND THE BEST
CHANCE TO KEEP PRECIPITATION GOING.
UNSTABLE TUESDAY WITH NORTHWESTERLY FLOW KEEPING TEMPERATURES ON
THE COOL SIDE. LAPSE RATES WILL BE QUITE STEEP SO ANTICIPATE
SHOWER ACTIVITY THOUGH PRECIPITATION AMOUNTS WILL BE LIGHT AND
GUSTY NORTHWEST WINDS ESPECIALLY IN SOUTHEAST MONTANA. AFTER A
COOLER NIGHT TUESDAY NIGHT WEDNESDAY SEES WEAK UPPER LEVEL RIDGING
MOVE INTO THE AREA WITH LEESIDE TROUGHING. THIS WILL BRING A MILD
WARMUP AND KEEP THINGS DRY. PATTERN DOES NOT LAST LONG ENOUGH FOR
WINDS TO BECOME A PROBLEM AT LIVINGSTON AS A SHORTWAVE ARRIVES
WEDNESDAY NIGHT TO WEAKEN PRESSURE GRADIENT BUT IF SHORTWAVE
TIMING CHANGES LIVINGSTON WINDS COULD APPROACH ADVISORY. BORSUM
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
MODELS REMAIN IN PRETTY GOOD AGREEMENT FOR THE EXTENDED
PERIOD...FAVORING A A COOLER AND PROGRESSIVE PATTERN.
THURSDAY...ANOTHER PACIFIC COLD FRONT RACES THROUGH THE REGION
WITH STRONG...GUSTY NW WINDS. UPPER LEVEL DYNAMICS AND INSTABILITY
SUPPORT THE POTENTIAL FOR LOWER ELEVATION RAIN AND SNOW SHOWERS
AND HIGHER ELEVATION SNOW...BUT DOWNSLOPE FLOW MAY KEEP PRECIP TO
A MINIMUM IN THE WESTERN FOOTHILLS.
ANOTHER POLAR AIRMASS SLIDES INTO THE REGION FROM THE NORTH AND
NORTHEAST THURSDAY NIGHT INTO FRIDAY AT THE SAME TIME A TROWAL-
TYPE FEATURE MOVES SOUTHWARD ACROSS THE EASTERN HALF OF THE REGION
AND SHORTWAVES MOVE ACROSS THE REGION IN NW FLOW ALOFT. THE LIFT
AND MOISTURE WILL COMBINE WITH THE COLD AIR...850 MB TEMPS WILL
DROP WELL BELOW 0C...TO GENERATE WIDESPREAD SNOW SHOWERS/LIGHT
SNOW. UPSLOPE FLOW AND OROGRAPHIC EFFECTS MAY ALSO HELP ENHANCE
SNOW POTENTIAL ACROSS THE CENTRAL AND WEST. HIGHS FRIDAY ARE ONLY
EXPECTED TO REACH THE LOW TO MID 30S.
SNOW SHOWERS WILL LINGER INTO SATURDAY AS THE AIRMASS REMAINS
UNSTABLE AND SHORTWAVES IN NW FLOW CONTINUE TO INTERACT WITH THE
COLDER AIR. TEMPS WILL REMAIN BELOW SEASONAL AVERAGES...WITH
HIGHS IN THE 30S TO AROUND 40.
SOME WEAK RIDGING TRIES TO NUDGE IN FROM THE WEST SUNDAY...THOUGH
MUCH OF THE REGION WILL REMAIN IN NW FLOW ALOFT. AS 850 MB TEMPS
RISE ABOVE 0C SUNDAY...HIGH TEMPS WILL BE A BIT WARMER...IN THE
UPPER 30S TO UPPER 40S. BEYOND SUNDAY...MODELS ARE TRENDING
TOWARDS ANOTHER SURGE OF COLD CANADIAN AIR EARLY NEXT WEEK...WITH
THE POTENTIAL FOR MORE SNOW. WE WILL NEED TO KEEP AN EYE ON THAT.
STC
&&
.AVIATION...
GUSTY NORTHERLY WINDS WILL CONTINUE AT ALL TERMINALS THROUGH THE
NIGHT TONITE. WINDS WILL DIMINISH AT KBIL...KLVM...AND KMLS BY
0500 UTC...AND AT KSHR BY THE DAWN HOURS. VISIBILITY CONDITIONS
WILL REMAIN SUSPECT AT ALL TERMINALS AS WELL...WITH A MIXTURE OF
RAIN AND OR SNOW IN THE FORECAST UNTIL THE EARLY MORNING HOURS.
THE HEAVIEST SNOW WILL FALL ALONG THE BEARTOOTH FOOTHILLS UNTIL
AROUND MIDNIGHT LOCAL TIME...CAUSING MOUNTAIN OBSCURATIONS.
CONDITIONS SHOULD CONTINUALLY GET BETTER DURING THE DAY ON
TUESDAY. SINGER
&&
.PRELIMINARY POINT TEMP/POPS...
TUE WED THU FRI SAT SUN MON
-----------------------------------------------------------
BIL 029/044 028/051 031/047 026/036 020/038 022/046 027/048
73/W 11/B 24/W 33/J 22/J 11/B 22/W
LVM 023/038 025/046 027/042 020/034 014/038 018/046 025/045
93/W 11/N 34/W 33/J 22/J 21/B 22/W
HDN 030/044 027/050 031/048 026/037 018/039 021/046 025/049
84/W 11/B 24/W 44/J 22/J 11/B 23/W
MLS 030/044 028/051 031/049 028/036 019/037 021/044 025/047
94/W 21/B 13/W 44/J 22/J 11/B 22/W
4BQ 030/042 026/049 029/048 026/037 019/038 020/045 025/047
+5/W 21/B 13/W 34/J 22/J 11/B 22/W
BHK 027/039 026/047 027/047 025/034 017/034 018/039 022/043
+4/W 31/B 13/W 45/J 22/J 11/B 22/W
SHR 028/039 021/048 024/046 023/036 015/038 017/047 023/046
+5/W 21/B 13/W 33/J 23/J 11/B 32/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY IN EFFECT UNTIL NOON MDT TUESDAY FOR
ZONES 36>38-57-58.
WINTER STORM WARNING IN EFFECT UNTIL MIDNIGHT MDT TONIGHT FOR
ZONES 56-66.
WINTER WEATHER ADVISORY IN EFFECT UNTIL MIDNIGHT MDT TONIGHT
FOR ZONE 63.
WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MDT TUESDAY FOR
ZONES 64-65.
WY...WINTER WEATHER ADVISORY IN EFFECT UNTIL NOON MDT TUESDAY FOR
ZONES 98-99.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1032 PM EDT MON MAR 17 2014
.SYNOPSIS...A LATE SEASON COLD AIR DAMMING WEDGE WILL REMAIN IN
PLACE THROUGH WEDNESDAY AS MODIFIED ARCTIC HIGH PRESSURE EXTENDS
SOUTHWARD INTO THE REGION AND MULTIPLE WAVES OF LOW PRESSURE DEVELOP
ALONG AND OFFSHORE THE CAROLINA COAST.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 1030 PM MONDAY...
TONIGHT: HIGH-END ADVISORY (BUT SUB-WARNING CRITERIA) ICING WITH
DISCOURAGED TRAVEL CONDITIONS OVER THE NORTHERN PIEDMONT...TO MORE
NUISANCE-TYPE IMPACTS WITH A FEW SLICK BRIDGES AND OVERPASSES ALONG
SOUTHERN ADVISORY AREAS OF THE SOUTHERN PIEDMONT...SANDHILLS...AND
CENTRAL COASTAL PLAIN.
A DEAMPLIFYING...POSITIVELY-TILTED SHORTWAVE TROUGH/SHEARING
VORTICITY MAX CENTERED OVER THE SOUTHERN APPALACHIANS THIS EVENING
WILL CONTINUE TO SHEAR NORTHEASTWARD INTO EASTERN NC...WHILE A MORE
POTENT ONE OVER THE MS DELTA REGION ASSUMES A NEGATIVE TILT AND
PIVOTS (HARMLESSLY FOR CENTRAL NC) ACROSS THE NORTHERN FL PENINSULA
TO OFFSHORE THE GA/SC COAST...THROUGH EARLY TUESDAY. DCVA ATTENDANT
TO THE LEAD DEAMPLIFYING WAVE SEEMS TO BE THE PRIMARY FORCING
MECHANISM FOR THE PRECIPITATION AREA THAT EXPANDED FROM WESTERN SC
TO THE NW NC PIEDMONT DURING THE PAST FEW HOURS. THIS FORCING...AND
ASSOCIATED MIXED PHASE PRECIPITATION PRODUCTION SUPPORTIVE OF 1) A
MIX OF SLEET WITH THE FREEZING RAIN AND 2) MODERATE PRECIPITATION
INTENSITY...SHOULD CONSEQUENTLY EDGE EASTWARD ACROSS CENTRAL NC -
THROUGH 05-06Z IN THE SOUTHERN AND WESTERN PIEDMONT AND 07-09Z IN
THE NORTHEAST PIEDMONT AND NORTHERN COASTAL PLAIN.
HOURLY PRECIPITATION RATES HAVE RANGED FROM A COUPLE OF HUNDREDTHS
TO MORE RECENTLY AS MUCH AS SIX HUNDREDTHS OF AN INCH IN THE
EXPANDING AREA OF PRECIPITATION. THESE HOURLY PRECIPITATION RATES
DURING THE TIMING REFERENCED ABOVE...WHICH IS CORROBORATED WITH NEAR
TERM RAP AND HRRR NWP GUIDANCE...WILL SUPPORT LIQUID EQUIVALENT
AMOUNTS OF 0.15"...TO PERHAPS AS MUCH AS ONE THIRD OF AN INCH IN
ISOLATED SPOTS. CONSIDERED UPGRADING PORTIONS OF THE ADVISORY
AREA...SUCH AS GUILFORD AND ALAMANCE NORTHEASTWARD TO COUNTIES ALONG
THE VA BORDER...TO A WARNING. HOWEVER...THE TENDENCY OF THE
PRECIPITATION TO SWITCH BETWEEN OR CONSIST OF A MIX OF SLEET AND
FREEZING RAIN - OWING TO A 00Z GSO-OBSERVED 4 C WARM NOSE AND MINUS
7 C COLD NOSE BELOW - SHOULD LIMIT ACCUMULATIONS OF ANY ONE
PRECIPITATION TYPE. HAVE INSTEAD OPTED TO "HIT THE WORDING A LITTLE
HARDER" IN THE ADVISORY...WITH SLEET ACCUMULATION AROUND A QUARTER
INCH OR LESS...AND FREEZING RAIN OF ONE TO TWO TENTHS OF AN
INCH...DERIVED FROM A 50/50 MIX OF FREEZING RAIN AND SLEET WITH
RATIOS OF 3-4:1...FROM THE AFOREMENTIONED LIQUID EQUIVALENT AMOUNTS
OF 0.15-0.30" OR SO. RECENT CHECKS WITH DUKE ENERGY INDICATE POWER
OUTAGES HAVE BEEN RELATIVELY SPARSE THUS FAR...WHICH SUGGESTS ICE
ACCRUAL IS NOT APPROACHING WARNING CRITERIA AND WELL-HANDLED BY THE
ADVISORY...DESPITE NUMEROUS CAR ACCIDENTS - INCLUDING AT LEAST
ONE FIERY ONE IN THE TRIAD.
ONCE THE MIXED PHASE PRECIPITATION COMES TO AN END...PERIODS OF
MOSTLY NON-MEASURABLE "DRIZZLY" PRECIPITATION - FREEZING IN THE
ADVISORY AREA AND LIQUID ELSEWHERE - WILL PREVAIL. 10 PM
TEMPERATURES WILL HOLD NEARLY STEADY IN THE UPPER 20S OVER THE
NORTHERN PIEDMONT...TO LOWER TO MIDDLE 30S OVER THE SOUTHERN
PIEDMONT AND SANDHILLS. -MWS
TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING BY LATE
MORNING/AROUND LUNCHTIME ACROSS THE NORTHERN PIEDMONT(EARLIER ACROSS
THE SOUTHERN PORTIONS OF THE ADVISORY AREA) AS THE MEASURABLE PRECIP
BEGINS TO PULL OUT OF THE AREA WITH THE EXITING UPPER WAVE.
SOUNDINGS SUPPORT CONTINUED LOW CLOUDS WITH POSSIBLE PATCHY/ISOLATED
DRIZZLE THROUGH THE AFTERNOON. HIGHS IN THE UPPER 30S NORTH TO
MID/UPPER 40S SOUTH. -CBL
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...
AN UPPER RIDGE MOVES THROUGH TUESDAY NIGHT...WITH INCREASING
DIFFLUENCE WEDNESDAY BEHIND THE RIDGE...AND IN ADVANCE OF AN UPPER
TROUGH THAT SHOULD MOVE INTO THE AREA BY THURSDAY. GUIDANCE OVER THE
LAST DAY OR SO HAS BEEN CONSISTENT IN THIS SYNOPTIC TREND...WITH ONE
DIFFERENCE BEING CONSISTENCY IN THE GUIDANCE MOVING THE SURFACE
FRONT THROUGH FASTER...POSSIBLY AS EARLY AS OVERNIGHT WEDNESDAY INTO
EARLY THURSDAY. THE COLD AIR WEDGE SHOULD REMAIN INTO MUCH OF THE
DAY WEDNESDAY...POSSIBLY STARTING TO ERODE LATE WEDNESDAY INTO
WEDNESDAY EVENING IN ADVANCE OF THE FRONT.
ANOTHER LONG-TERM CONSISTENCY IS KEEPING WET BULB SURFACE
TEMPERATURES ABOVE 0C IN CENTRAL NORTH CAROLINA FOR TUESDAY NIGHT
INTO WEDNESDAY. PARTIAL THICKNESSES ARE ALSO PRIMARILY IN THE LIQUID
RANGE AND ARE ACTUALLY WARMER ON THE NAM OVERNIGHT TUESDAY INTO
EARLY WEDNESDAY...WITH ONLY THE PERIOD AROUND 06Z WEDNESDAY ON THE
GFS POSSIBLY INTO THE FREEZING RANGE. HOWEVER...WITH SURFACE
TEMPERATURES FORECAST TO STAY JUST ABOVE FREEZING AT THEIR
COLDEST...WILL CONTINUE THE FORECAST OF ANY PRECIPITATION TYPE BEING
LIQUID IN THIS PART OF THE FORECAST PERIOD.
FOR TUESDAY NIGHT INTO WEDNESDAY MORNING...BOTH THE GFS AND NAM BUFR
SOUNDINGS MAINTAIN A VERY MOIST BOUNDARY LAYER. SHALLOW INSTABILITY
NEAR THE TOP OF THE MOIST LAYER INCREASES OVERNIGHT TUESDAY INTO
WEDNESDAY MORNING AS THAT MOIST LAYER DEEPENS. EARLY AT NIGHT...ANY
PRECIPITATION WOULD LIKELY BE DRIZZLE OR VERY PATCHY LIGHT RAIN...
WITH A CHANCE OF RAIN AND DRIZZLE OVERNIGHT THROUGH WEDNESDAY
MORNING FOR MUCH OF CENTRAL NORTH CAROLINA AS...ADDITIONALLY...A MID-
LEVEL SHORTWAVE MOVES IN AND THERE EXISTS WEAK 850MB LIFT. DURING
THE DAY WEDNESDAY...BOUNDARY LAYER MOISTURE BECOMES MORE SHALLOW.
THE GFS...AND EVEN THE NAM BUT TO A LESSER DEGREE...INCREASES WINDS
AT 850MB APPRECIABLY AND IT WILL BE INTERESTING TO SEE WHETHER THESE
WINDS AND SOME WARM-AIR ADVECTION EITHER AT OR JUST BELOW 850MB
HELPS TO CAP SOME OF THE MOISTURE FURTHER OR HELPS ERODE THE CLOUD
COVER. THE NAM IS ACTUALLY MORE AGGRESSIVE WITH SOME CLEARING AND
WARMING LATE...BUT FOR THIS FORECAST WILL LEAN SLOWER WITH THE WEDGE
NOT COMPLETELY ERODING UNTIL WEDNESDAY NIGHT CLOSER TO THE APPROACH
OF THE SURFACE FRONT.
WEDNESDAY NIGHT...THE GFS IS DRY AND MORE STABLE THAN THE NAM...
ALTHOUGH THE GFS DOES FORECAST A WEAK INCREASE IN 850MB THETA-E
VALUES AND THE APPROACH OF THE RIGHT ENTRANCE REGION OF A 115KT
300MB JET...AND A 90KT 500MB JET. WILL SHOW JUST A SLIGHT CHANCE OF
SHOWERS THROUGHOUT THE NIGHT FOR NOW. BUFR SOUNDINGS FROM BOTH THE
GFS AND NAM WOULD SUGGEST THAT...WITH THE APPROACH OF THE JETS
ALOFT...ALONG WITH THE APPROACHING FRONT...AT LEAST A SLIGHT CHANCE
IS WARRANTED AS MID-LEVEL MOISTURE INCREASES FOR A PERIOD. AS FOR
TEMPERATURES IN THIS PERIOD...AFTER LOWS MOSTLY IN THE 30S TUESDAY
NIGHT...WILL LEAN TOWARD THE COOLER MAV MOS FOR HIGHS WEDNESDAY...
AND SHOW ONLY A MODEST DIURNAL FALL WEDNESDAY NIGHT IN A SOUTHWEST
TO WEST LOW-LEVEL FLOW IN ADVANCE OF THE FRONT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 100 PM MONDAY...
THE LONG-TERM GUIDANCE CONTINUES TO BE CONSISTENT WITH AN UPPER
TROUGH MOVING THROUGH CENTRAL NORTH CAROLINA THURSDAY...WITH A LOW
AMPLITUDE RIDGE ALOFT MOVING INTO THE REGION FRIDAY. THE ECMWF
REMAINS SLIGHTLY MORE AMPLIFIED THAN THE GFS WITH ANOTHER TROUGH
APPROACHING CENTRAL NORTH CAROLINA SATURDAY...BUT THE DIFFERENCES
ARE NOT AS GREAT AS WITH THE GUIDANCE EARLY SUNDAY...WITH BOTH THE
GFS AND ECMWF SHOWING MORE OF A NORTHWEST FLOW UNDER SURFACE HIGH
PRESSURE FOR THE END OF THE WEEKEND AND THE START OF NEXT WEEK. BOTH
THE GFS AND ECMWF FORECAST LOW PRESSURE IN THE GULF TOWARD THE END
OF THIS LONG-TERM PERIOD...AND WHILE THERE WILL BE A NEED TO MONITOR
THE EVOLUTION OF LOW PRESSURE OVER TIME...THIS FORECAST WILL SHOW
CONTINUED DRY CONDITIONS SUNDAY INTO MONDAY. AN ALTERNATIVE COULD BE
AN INCREASE IN PRECIPITATION CHANCES EARLY NEXT WEEK...BUT IT IS
CERTAINLY TOO EARLY TO TRY AND REFINE THOSE AND WILL LEAVE OUT OF
THE FORECAST FOR NOW.
WITH A LITTLE FASTER FRONTAL TIMING THURSDAY...WILL SHOW DRY WEATHER
THURSDAY AS HIGH PRESSURE BUILDS IN BEHIND THE FRONT...AND DRY AGAIN
AT LEAST THROUGH FRIDAY EVENING AS SURFACE HIGH PRESSURE RETREATS
OFF OF THE COAST. AS THE SURFACE HIGH RETREATS...THE GFS HAS MORE OF
A LOW-LEVEL TRAJECTORY FROM THE ATLANTIC AND BRINGS INTO CENTRAL
NORTH CAROLINA MORE LOW-LEVEL MOISTURE LATE FRIDAY NIGHT INTO EARLY
SATURDAY...COMPARED TO THE ECMWF WHICH HAS MORE OF A SOUTHWEST FLOW
THROUGH 850MB AND LESS LOW-LEVEL MOISTURE UNTIL DURING THE DAY ILL
KEEP THE OVERNIGHT FORECAST DRY FOR NOW...SHOWING THE POSSIBILITY OF
A SHOWER EARLY IN THE COASTAL PLAIN WITH RESIDUAL BOUNDARY LAYER
MOISTURE...THOUGH LATER FORECASTS MAY NEED TO INTRODUCE A SLIGHT
CHANCE LATE WITH THE FRONT IF THERE IS ENOUGH LOW-LEVEL MOISTURE
REMAINING ACCOMPANIED BY A BRIEF INCREASE IN MID-LEVEL MOISTURE WITH
THE FRONT. PROPER ON SATURDAY. FOR CONSISTENCY WILL KEEP THE
FORECAST DRY OVERNIGHT FRIDAY...THOUGH AN ALTERNATIVE...OVER
TIME...COULD BE WIDELY SCATTERED SHOWERS DEVELOPING LATE FRIDAY
NIGHT INTO EARLY SATURDAY MORNING.
THE GFS AND ECMWF ARE CONSISTENT WITH A FRONTAL PASSAGE SATURDAY...
AND THE FORECAST WILL REFLECT A CHANCE OF SHOWERS THOUGH...FOR THIS
FORECAST...WILL CONTINUE WITH NO MENTION OF THUNDER. COARSE ECMWF
SOUNDINGS ARE A LITTLE MORE UNSTABLE THAN THE GFS...WHICH HAS A
SUBTLE CAP ALOFT AROUND 700MB. THE CAP AROUND 700MB WOULD KEEP
INSTABILITY LOW ENOUGH FOR NO THUNDER...BUT GIVEN THE FRONTAL
TIMING...THERE COULD BE A THUNDERSTORM OR TWO PARTICULARLY SOUTH AND
EAST OF THE TRIAD AND THIS COULD BE MENTIONED IN LATER FORECASTS IF
MORE INSTABILITY BECOMES FORECAST. SUNDAY AND MONDAY...DRY AND COOL
UNDER SURFACE HIGH PRESSURE THAT BUILDS IN QUICKLY BEHIND THE FRONT.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 847 PM MONDAY...
IFR CONDITIONS CURRENTLY ACROSS THE AREA WILL CONTINUE THROUGH THE
NEXT 24 HOURS UNDER A COLD AIR DAMMING REGIME. LIGHT FREEZING
RAIN... FREEZING DRIZZLE AND SLEET WILL CONTINUE OVERNIGHT... BEFORE
CHANGING TO DRIZZLE BETWEEN 12-15Z TUESDAY AT MOST SITES... WITH THE
EXCEPTION OF KFAY WHICH SHOULD REMAIN DRIZZLE/LIGHT RAIN THROUGH THE
DURATION. WINDS WILL REMAIN NE AROUND 8-10 KTS.
BEYOND THE 18Z VALID TAF PERIOD...ADVERSE AVIATION CONDITIONS...
PARTICULARLY IN IFR AND OCCASIONAL MVFR CEILINGS...AND AREAS OF
DRIZZLE AND SPOTTY LIGHT RAIN...SHOULD PERSIST INTO WEDNESDAY.
FINALLY ON WEDNESDAY...CEILINGS SHOULD GRADUALLY START TO LIFT...
ALTHOUGH IT SHOULD BE NOTED THAT ON SOME GUIDANCE THE CEILINGS OVER
THE NORTHWEST PIEDMONT MAY NOT IMPROVE MARKEDLY UNTIL INTO WEDNESDAY
NIGHT. IF WINDS LIGHTEN UP AS SKIES CLEAR...AT LEAST SOME LIGHT FOG
COULD DEVELOP WEDNESDAY NIGHT.
THURSDAY THROUGH FRIDAY...ANTICIPATE VFR CONDITIONS. LATE FRIDAY
NIGHT INTO SATURDAY...THERE IS THE POTENTIAL FOR AREAS OF SUB-VFR
CONDITIONS IN LOW CLOUDS AND SHOWERS...ALONG AND AHEAD OF A COLD
FRONT THAT WILL MOVE THROUGH THE REGION ON SATURDAY. COLDER HIGH
PRESSURE AND DRIER AIR THEN BUILD IN FROM THE NORTH SATURDAY NIGHT
INCREASING PROBABILITIES OF A RETURN TO WIDESPREAD VFR CONDITIONS.
&&
.CLIMATE...
THE RECORD LOW MAXIMUM TEMPERATURES FOR MARCH 18 (TUESDAY) ARE...
KGSO...36 DEGREES FROM 1961.
KRDU...36 DEGREES FROM 1892.
KFAY...41 DEGREES FROM 1998.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO NOON EDT
TUESDAY FOR NCZ011-026>028-040>043-073>077.
WINTER WEATHER ADVISORY UNTIL NOON EDT TUESDAY FOR NCZ007>010-
021>025-038-039.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...MWS/CBL
SHORT TERM...DJF
LONG TERM...DJF
AVIATION...SEC/DJF
CLIMATE...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
145 PM EDT SUN MAR 16 2014
.SYNOPSIS... AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE SOUTHERN
PLAINS TODAY AND THEN TRACK EASTWARD ALONG THE NORTHERN GULF COAST
STATES AND COASTAL CAROLINAS THROUGH TONIGHT.
&&
.NEAR TERM /TODAY/...
AS OF 1030 AM SUNDAY...
A WEAK COLD FRONT HAS DRIFTED SOUTH OF THE AREA AND ESSENTIALLY
WASHED OUT THIS MORNING...WITH A SECONDARY ARCTIC FRONT DRAPED
ACROSS SOUTH-CENTRAL VA. MEANWHILE...AN ELONGATED AND
COMPLEX...POSITIVELY TILED UPPER TROUGH IS EVOLVING OVER THE SOUTHERN
PLAINS...WITH A LEAD SHORTWAVE AND ASSOCIATED 1002MB SURFACE LOW
KICKING NORTHEAST ACROSS THE LOWER/MID MS RIVER VALLEY REGION. AND
EXPANSIVE PRECIP SHIELD IS SPREAD ACROSS GA/SC AND INTO SOUTHWESTERN
NC...WITH MEASURABLE PRECIP NOW ONT HE DOORSTEPS OF THE SOUTHERN
PIEDMONT. WHILE LARGE SCALE FORCING...WEAK HEIGHT FALLS AND WARM
ADVECTION....WILL DRIVE PRECIP ACROSS THE AREA TODAY...THERE ARE TWO
MAIN CONCERNS EVOLVING IN THE UPSTREAM RADAR/SATELLITE OBS: 1) A DRY
SLOT SURGING ACROSS NORTHERN AL AND TN AND 2) THE
ORIENTATION/TRACK OF CONVECTION ACROSS THE GULF COAST STATES.
ISENTROPIC LIFT WILL BE MAXIMIZED ACROSS CENTRAL NC BETWEEN 18Z AND
00Z...WHICH IS WHEN CONFIDENCE IN HIGHEST POPS/QPF OCCURS. THE DRY
SLOT MAY HELP TO CUT DOWN ON PRECIP RATES ACROSS WESTERN PORTION
OF THE AREA BY AS EARLY AS 21Z...WHILE THE GULF COAST CONVECTION
MAY ACT TO DIRECT THE BEST LOW-LEVEL JETTING AND WARM ADVECTION
TOWARD THE CAROLINA COASTAL AREAS. THE LATEST RAP QPF AND HRRR
SIMULATED REFLECTIVITY HINT AT THIS...WITH THE AXIS OF HEAVIEST
PRECIP ACROSS CENTRAL SC AND EASTERN NC. HAVE ADJUST POPS PRIOR TO
NOON TO REFLECT CURRENT RADAR TRENDS...WITH CATEGORICAL STILL AFTER
NOON. MINOR ADJUSTMENTS TO QPF LEAD TO NEAR AND INCH IN THE FAR
SOUTH AND ONE HALF INCH ACROSS THE NORTH.
TEMPS ARE LIKELY REACHING THEIR HIGHS FOR TODAY...MOSTLY IN THE 50S
AREAWIDE. EVAPORATIVE COOLING AND SLOWLY STRENGTHENING COLD
ADVECTION FROM THE NORTH...AS A SURFACE WAVE BEGINS TO DEVELOP
OFFSHORE...WILL CAUSE TEMPS TO HOLD STEADY OR FALL INTO THE 40S
(MAINLY NORTH) THIS AFTERNOON.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AS OF 320 AM SUNDAY...
...WINTER WEATHER ADVISORY FOR MAINLY MINOR ACCUMULATIONS OF
FREEZING RAIN WILL BE ISSUED FOR MIDNIGHT TO NOON MONDAY FOR
LOCATIONS NEAR AND NORTH OF INTERSTATE 85...
DIFFICULT FORECAST DURING THIS PERIOD AS THERE CONTINUES TO BE SOME
SIGNIFICANT DIFFERENCES IN THE NWP GUIDANCE...ESPECIALLY FOR THE
MONDAY INTO TUESDAY TIME FRAME. THE END RESULT IS A COMPLEX AND BUSY
FORECAST WITH DIFFERING IMPACTS...MOST OF WHICH WILL BE MINOR TO
MODERATE.
WIDESPREAD RAIN WILL BE ONGOING THIS EVENING AT THE START OF THE
SHORT TERM PERIOD AS A SURGE IN LOW LEVEL WARM ADVECTION
PRECIPITATION ENHANCED BY THE RIGHT ENTRANCE REGION OF A 125KT UPPER
LEVEL JET ACROSS THE MID ATLANTIC. AT THE SAME TIME A BACK DOOR COLD
FRONT WILL PUSH SOUTH INTO CENTRAL NC WITH A PUSH OF CONSIDERABLY
COLDER AND DRIER AIR AT THE SURFACE. PRECIPITATION COVERAGE AND
INTENSITY WILL WANE CONSIDERABLY LATE IN THE EVENING AND OVERNIGHT
AS THE BEST FORCING LIFTS NORTHEAST OF THE AREA AND AS THE MID/UPPER
LEVELS DRY OUT. LIGHT QPF AMOUNTS ON THE ORDER OF .10 INCHES WEST TO
.15 INCHES EAST ARE EXPECTED AFTER MIDNIGHT. GUIDANCE DIFFERS WITH
THE STRENGTH OF THE SURFACE BASED COLD AIR OVER CENTRAL NC. THE NAM
IS CONSIDERABLY COLDER...LIKELY AS A RESULT OF THE SLIGHTLY STRONGER
AND FURTHER SOUTH PLACEMENT OF THE MODERATELY STRONG SURFACE HIGH
WHICH PROVIDES A CLOSER COLD AIR SOURCE REGION AND WHICH DEVELOPS A
SLIGHTLY STRONGER PRESSURE GRADIENT TO PUSH THE COLD/DRY AIR FURTHER
SOUTH. USED A BLEND OF GFS/ECMWF GUIDANCE TO PRODUCE SURFACE
TEMPERATURES WHICH FALL TO FREEZING AT AROUND 3 TO 4 AM NEAR THE VA
BORDER. THE NAM GIVES A SFC TEMP OF 26 AT KGSO AT 8AM WHILE THE GFS
GIVES A COLD BUT MORE REASONABLE 29. THE 32 DEGREE SFC TEMP LINE
REACHES AS FAR SOUTH AS LOUISBURG....DURHAM AND HIGH POINT MONDAY
MORNING WITH SUBFREEZING TEMPS FURTHER NORTH. MOST OF THE
PRECIPITATION SHOULD FALL AS FREEZING RAIN OR FREEZING DRIZZLE WITH
A BRIEF PERIOD OF SLEET POSSIBLE WHEN MOISTURE IS STILL SUFFICIENTLY
DEEP ENOUGH FOR ICE ALOFT. WITH THIS IN MIND...WILL ISSUE A WINTER
WEATHER ADVISORY FROM MIDNIGHT THROUGH NOON MONDAY FOR OUR NORTHERN
TIER OF COUNTIES...MAINLY NORTH OF INTERSTATE 95. SURFACE
TEMPERATURES RECOVER A BIT ON MONDAY AS PRECIP EBBS AND THE SURGE OF
COLD/DRY AIR SUBSIDES. IN ADDITION...IT IS DIFFICULT TO GET
MEANINGFUL ICE ACCRUAL WITH FREEZING RAIN DURING THE DAYTIME HOURS
IN MID MARCH AT OUR LATITUDE. SO EXPECT MOST OF THE FREEZING RAIN
AND DRIZZLE TO FALL BETWEEN 4AM AND 9AM WITH ACCUMULATIONS GENERALLY
CONFINED TO ELEVATED SURFACES SUCH AS TREE TOPS IN THE COLDER AIR
ALOFT AND REMOVED FROM THE GROUND WHICH SHOULD BE RADIATING SOME
HEAT. LOWS MONDAY MORNING WILL RANGE FROM NEAR 30 AT THE VA BORDER
TO THE UPPER 30S TOWARD THE SC BORDER.
EXPECT PRECIPITATION TO BE RATHER LIGHT AND INTERMITTENT LATE MONDAY
AND MONDAY AFTERNOON AS DRYING ALOFT MOVES IN AND CENTRAL NC IS IN A
REGION OF WEAK RIDGING BETWEEN SYSTEMS. SENSIBLE WEATHER IS BEST
CHARACTERIZED AS CLOUDY SKIES WITH PERIODS OF LIGHT RAIN OR DRIZZLE
WITH POPS IN THE 30-40 PERCENT RANGE. TEMPERATURES SHOULD RECOVER
SLIGHTLY WITH THE ABSENCE OF WIDESPREAD RAIN AND SOME INSOLATION
THROUGH THE CLOUD COVER. HIGHS WILL RANGE IN THE 34 NEAR THE VA
BORDER TO THE LOWER 40S NEAR THE SC BORDER.
ANOTHER SURGE OF COLD AIR IS EXPECTED ON MONDAY NIGHT WITH SURFACE
TEMPERATURES GETTING EVEN COLDER THAN MONDAY MORNING. BOTH THE
GFS/ECMWF DRIVE THE WET BULB FREEZING LINE EVEN FURTHER SOUTH ACROSS
THE WESTERN PIEDMONT WITH THE ORIENTATION OF THE WBZ LINE SHIFTING
FROM WEST-EAST ON MONDAY MORNING TO MORE SOUTHWEST-NORTHEAST BY
TUESDAY MORNING. THE NAM REMAINS AN OUTLIER DURING THIS PERIOD AS IT
APPEARS TO GO BONKERS BY DEVELOPING AN INTENSE SURFACE LOW NEAR
SAVANNAH AND DRIVES THE LOW NORTHEAST ALONG THE CAROLINA COAST.
THERE IS ANOTHER PERIOD OF FREEZING RAIN AND EVEN SOME SLEET
POSSIBLE MONDAY NIGHT WITH THE ULTIMATE IMPACT DRIVEN NOT ONLY BY
THE MOUNT OF COLD AIR BUT MORE IMPORTANTLY BY THE QPF. GUIDANCE
DIFFERS WITH THE AMOUNT AND TIMING OF PRECIPITATION DURING THE
PERIOD BUT THERE WILL LIKELY BE AROUND 0.10 TO POSSIBLY 0.20 INCHES
OF LIQUID EQUIVALENT THAT FALLS ACROSS THE COLDER AND POTENTIALLY
WINTRY WEATHER AREA. LOWS TUESDAY MORNING SHOULD RANGE FROM NEAR 27
ACROSS THE FAR NORTHERN PARTS OF THE TRIAD TO MID 30S ACROSS THE
SOUTHEAST.
CONTINUED CLOUDY AND UNSETTLED ON TUESDAY AS BOTH THE GFS/ECMWF PUSH
A SURFACE WAVE AWAY FROM THE MID ATLANTIC WHILE THE NAM APPEARS LOST
BY DRIVING AN INTENSIFYING SURFACE WAVE INTO THE CHESAPEAKE BAY.
TEMPERATURES SHOULD RECOVER A BIT AND CLIMB ABOVE FREEZING
EVERYWHERE BY MID MORNING BEFORE HIGHS EVENTUALLY REACH THE 40-45
DEGREE RANGE. THE GREATEST CHANCE OF PRECIPITATION WILL OCCUR
ACROSS THE SOUTHEAST AHEAD OF THE SOUTHERN STREAM SHORT WAVE AND
CLOSER TO THE SURFACE WAVE.
THREE-DAY QPF VALUES RANGE FROM AROUND AN INCH NEAR THE VA BORDER TO
1.5 INCHES NEAR THE SC BORDER ALTHOUGH SOME GUIDANCE...ESPECIALLY
THE NAM/SREF ARE CONSIDERABLY HIGHER. MUCH OF THAT PRECIPITATION
ARRIVES SUNDAY AFTERNOON AND EVENING WITH GENERALLY LIGHTER AMOUNTS
EXPECTED FOR MONDAY AND TUESDAY. THESE AMOUNTS ARE LIKELY
INSUFFICIENT FOR A FLASH FLOOD OR AERIAL FLOOD WATCH. SEE THE
HYDROLOGY SECTION BELOW FOR MORE DETAILS. -BLAES
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 300 AM SUNDAY...
A LOT OF UNCERTAINTY STILL EXISTS IN THE LONG TERM. A SERIES OF
SHORTWAVES ARE EXPECTED TO MOVE THROUGH THE AREA AND THE GFS AND
ECMWF HANDLE THEM DIFFERENTLY WITH RESPECT TO TIMING...AMPLITUDE...
AND PRECIPITATION. IN GENERAL...THE ECMWF IS SLOWER...WETTER...AND
COOLER THAN THE GFS. ALTHOUGH THERE IS A DESCENT CHANCE THAT
PRECIPITATION WILL LINGER THROUGH THE DAY WEDNESDAY...IT SHOULD BE
ALL LIQUID AND FAIRLY LIGHT. GIVEN THE MODEL DISCREPANCIES AND
RESULTANT UNCERTAINTY...WILL MAINTAIN A MAINLY DRY FORECAST
WEDNESDAY NIGHT THROUGH SUNDAY...WITH THE EXCEPTION OF A SLIGHT
CHANCE FOR RAIN WITH THE FROPA ON SATURDAY. IN THE LOW LEVELS...THE
COLD AIR WEDGE...PRESENT IN BOTH MODELS OVER THE NORTHWEST...SHOULD
WEAKEN AS A FRONTAL BOUNDARY APPROACHES FROM THE WEST THURSDAY. A
WEAK SURFACE HIGH WILL MOVE THROUGH THE AREA BEHIND THE FRONT ON
FRIDAY...AHEAD OF THE NEXT FRONTAL SYSTEM TO THE WEST. BOTH MODELS
INDICATE THE COLD FRONT WITH THIS SYSTEM WILL PROGRESS THROUGH
CENTRAL NC SATURDAY EVE/NIGHT...ALTHOUGH THE SPEED AND ORIENTATION
DIFFER BETWEEN THE MODELS. HIGH PRESSURE IS AGAIN EXPECTED TO BUILD
IN BEHIND THE FRONT. HIGH TEMPERATURES WILL GENERALLY INCREASE
THROUGH SATURDAY...LOWEST IN THE NORTHWEST AND HIGHEST IN THE
SOUTHEAST.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 145 PM SUNDAY...
MEDIUM TO LOW CONFIDENCE IN THE CURRENT TAF PERIOD. PRECIP AND LOW
CEILINGS HAVE BEEN SLOW TO SPREAD ACROSS CENTRAL NC FROM THE
SOUTHWEST...WITH RAIN JUST RECENTLY REACHING THE TRIAD TERMINALS AND
RDU. CEILINGS ARE STILL AT VFR LEVELS...BUT ARE EXPECTED TO FALL TO
MVFR BY AROUND 21Z AND THEN TO IFR BY 03-06Z. VSBYS WILL ALSO DROP
TO MOSTLY AROUND 3SM... POSSIBLY LOWER IN HEAVIER RAIN...WHICH IS
MORE LIKELY AT KRWI AND KFAY. A COASTAL WILL DEVELOP OVERNIGHT AND
CAUSE NORTHEASTERLY WINDS TO INCREASE INTO THE 12-15KT RANGE. LATER
TONIGHT...COLDER AIR WILL PUSH INTO THE AREA FROM THE NORTH...AND A
PERIOD OF FREEZING RAIN OR DRIZZLE WILL BE POSSIBLE AT KGSO AND
KINT...MOSTLY BETWEEN 09Z AND 15Z. PRECIP RATES WILL REMAIN LIGHT AND
IMPACTS ARE NOT EXPECTED TO BE SIGNIFICANT. CEILINGS WILL REMAIN
LOW...LIKELY IN THE IFR TO MVFR RANGE THROUGH THE END OF THE TAF
PERIOD.
OUTLOOK... LOW CEILINGS WILL CONTINUE TO PLAGUE AREA TERMINALS
MONDAY INTO TUESDAY...WITH ANOTHER PERIOD OF FREEZING RAIN POSSIBLE
NORTH AND WEST OF KRDU ON MONDAY NIGHT AND EARLY TUESDAY.
IMPROVEMENT WILL LIKELY NOT COME UNTIL WEDNESDAY.
&&
.HYDROLOGY...
AS OF 1115 AM SUNDAY...
WITH FLASH FLOOD GUIDANCE STILL 2.5 INCHES OR GREATER FOR THREE
HOURS OR GREATER...WILL CONTINUE TO REFRAIN FROM ANY FLOOD WATCHES
GIVEN THE EXPECTED QPF. SHOULD NOTE THAT DEEP CONVECTION OVER THE
FAR SOUTHEAST CONUS MAY IMPACT SOME OF THE EXPECTED HIGHER RAINFALL
TOTALS OVER THE SANDHILLS AND COASTAL PLAIN OF CENTRAL NORTH
CAROLINA. CONSISTENTLY IT APPEARS THE PROBABILITY OF MINOR FLOOD
STAGE BEING REACHED IS HIGHEST AT SMITHFIELD WHERE A RIVER FLOOD
WARNING IS IN EFFECT...LESS SO AT CLAYTON...AND NOTICEABLY LOWER AT
OTHER MAINSTEM RIVER SITES EVEN BASED ON THE HIGHEST QPF AVAILABLE
ON THE ENSEMBLE RIVER LEVEL OUTPUT OF THE MMEFS.
&&
.CLIMATE...
THE RECORD LOW MAXIMUM TEMPERATURES FOR MARCH 17 (MONDAY) ARE...
KGSO...38 DEGREES FROM 2005.
KRDU...32 DEGREES FROM 1892.
KFAY...39 DEGREES FROM 2005.
THE RECORD LOW MAXIMUM TEMPERATURES FOR MARCH 18 (TUESDAY) ARE...
KGSO...36 DEGREES FROM 1961.
KRDU...36 DEGREES FROM 1892.
KFAY...41 DEGREES FROM 1998.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT
MONDAY FOR NCZ007>009-021>023.
&&
$$
SYNOPSIS...MWS
NEAR TERM...MWS/SMITH
SHORT TERM...BLAES
LONG TERM...KCP
AVIATION...SMITH
HYDROLOGY...DJF
CLIMATE...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1115 AM EDT SUN MAR 16 2014
.SYNOPSIS... AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE SOUTHERN
PLAINS TODAY AND THEN TRACK EASTWARD ALONG THE NORTHERN GULF COAST
STATES AND COASTAL CAROLINAS THROUGH TONIGHT.
&&
.NEAR TERM /TODAY/...
AS OF 1030 AM SUNDAY...
A WEAK COLD FRONT HAS DRIFTED SOUTH OF THE AREA AND ESSENTIALLY
WASHED OUT THIS MORNING...WITH A SECONDARY ARCTIC FRONT DRAPED
ACROSS SOUTH-CENTRAL VA. MEANWHILE...AN ELONGATED AND
COMPLEX...POSITIVELY TILED UPPER TROUGH IS EVOLVING OVER THE SOUTHERN
PLAINS...WITH A LEAD SHORTWAVE AND ASSOCIATED 1002MB SURFACE LOW
KICKING NORTHEAST ACROSS THE LOWER/MID MS RIVER VALLEY REGION. AND
EXPANSIVE PRECIP SHIELD IS SPREAD ACROSS GA/SC AND INTO SOUTHWESTERN
NC...WITH MEASURABLE PRECIP NOW ONT HE DOORSTEPS OF THE SOUTHERN
PIEDMONT. WHILE LARGE SCALE FORCING...WEAK HEIGHT FALLS AND WARM
ADVECTION....WILL DRIVE PRECIP ACROSS THE AREA TODAY...THERE ARE TWO
MAIN CONCERNS EVOLVING IN THE UPSTREAM RADAR/SATELLITE OBS: 1) A DRY
SLOT SURGING ACROSS NORTHERN AL AND TN AND 2) THE
ORIENTATION/TRACK OF CONVECTION ACROSS THE GULF COAST STATES.
ISENTROPIC LIFT WILL BE MAXIMIZED ACROSS CENTRAL NC BETWEEN 18Z AND
00Z...WHICH IS WHEN CONFIDENCE IN HIGHEST POPS/QPF OCCURS. THE DRY
SLOT MAY HELP TO CUT DOWN ON PRECIP RATES ACROSS WESTERN PORTION
OF THE AREA BY AS EARLY AS 21Z...WHILE THE GULF COAST CONVECTION
MAY ACT TO DIRECT THE BEST LOW-LEVEL JETTING AND WARM ADVECTION
TOWARD THE CAROLINA COASTAL AREAS. THE LATEST RAP QPF AND HRRR
SIMULATED REFLECTIVITY HINT AT THIS...WITH THE AXIS OF HEAVIEST
PRECIP ACROSS CENTRAL SC AND EASTERN NC. HAVE ADJUST POPS PRIOR TO
NOON TO REFLECT CURRENT RADAR TRENDS...WITH CATEGORICAL STILL AFTER
NOON. MINOR ADJUSTMENTS TO QPF LEAD TO NEAR AND INCH IN THE FAR
SOUTH AND ONE HALF INCH ACROSS THE NORTH.
TEMPS ARE LIKELY REACHING THEIR HIGHS FOR TODAY...MOSTLY IN THE 50S
AREAWIDE. EVAPORATIVE COOLING AND SLOWLY STRENGTHENING COLD
ADVECTION FROM THE NORTH...AS A SURFACE WAVE BEGINS TO DEVELOP
OFFSHORE...WILL CAUSE TEMPS TO HOLD STEADY OR FALL INTO THE 40S
(MAINLY NORTH) THIS AFTERNOON.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AS OF 320 AM SUNDAY...
...WINTER WEATHER ADVISORY FOR MAINLY MINOR ACCUMULATIONS OF
FREEZING RAIN WILL BE ISSUED FOR MIDNIGHT TO NOON MONDAY FOR
LOCATIONS NEAR AND NORTH OF INTERSTATE 85...
DIFFICULT FORECAST DURING THIS PERIOD AS THERE CONTINUES TO BE SOME
SIGNIFICANT DIFFERENCES IN THE NWP GUIDANCE...ESPECIALLY FOR THE
MONDAY INTO TUESDAY TIME FRAME. THE END RESULT IS A COMPLEX AND BUSY
FORECAST WITH DIFFERING IMPACTS...MOST OF WHICH WILL BE MINOR TO
MODERATE.
WIDESPREAD RAIN WILL BE ONGOING THIS EVENING AT THE START OF THE
SHORT TERM PERIOD AS A SURGE IN LOW LEVEL WARM ADVECTION
PRECIPITATION ENHANCED BY THE RIGHT ENTRANCE REGION OF A 125KT UPPER
LEVEL JET ACROSS THE MID ATLANTIC. AT THE SAME TIME A BACK DOOR COLD
FRONT WILL PUSH SOUTH INTO CENTRAL NC WITH A PUSH OF CONSIDERABLY
COLDER AND DRIER AIR AT THE SURFACE. PRECIPITATION COVERAGE AND
INTENSITY WILL WANE CONSIDERABLY LATE IN THE EVENING AND OVERNIGHT
AS THE BEST FORCING LIFTS NORTHEAST OF THE AREA AND AS THE MID/UPPER
LEVELS DRY OUT. LIGHT QPF AMOUNTS ON THE ORDER OF .10 INCHES WEST TO
.15 INCHES EAST ARE EXPECTED AFTER MIDNIGHT. GUIDANCE DIFFERS WITH
THE STRENGTH OF THE SURFACE BASED COLD AIR OVER CENTRAL NC. THE NAM
IS CONSIDERABLY COLDER...LIKELY AS A RESULT OF THE SLIGHTLY STRONGER
AND FURTHER SOUTH PLACEMENT OF THE MODERATELY STRONG SURFACE HIGH
WHICH PROVIDES A CLOSER COLD AIR SOURCE REGION AND WHICH DEVELOPS A
SLIGHTLY STRONGER PRESSURE GRADIENT TO PUSH THE COLD/DRY AIR FURTHER
SOUTH. USED A BLEND OF GFS/ECMWF GUIDANCE TO PRODUCE SURFACE
TEMPERATURES WHICH FALL TO FREEZING AT AROUND 3 TO 4 AM NEAR THE VA
BORDER. THE NAM GIVES A SFC TEMP OF 26 AT KGSO AT 8AM WHILE THE GFS
GIVES A COLD BUT MORE REASONABLE 29. THE 32 DEGREE SFC TEMP LINE
REACHES AS FAR SOUTH AS LOUISBURG....DURHAM AND HIGH POINT MONDAY
MORNING WITH SUBFREEZING TEMPS FURTHER NORTH. MOST OF THE
PRECIPITATION SHOULD FALL AS FREEZING RAIN OR FREEZING DRIZZLE WITH
A BRIEF PERIOD OF SLEET POSSIBLE WHEN MOISTURE IS STILL SUFFICIENTLY
DEEP ENOUGH FOR ICE ALOFT. WITH THIS IN MIND...WILL ISSUE A WINTER
WEATHER ADVISORY FROM MIDNIGHT THROUGH NOON MONDAY FOR OUR NORTHERN
TIER OF COUNTIES...MAINLY NORTH OF INTERSTATE 95. SURFACE
TEMPERATURES RECOVER A BIT ON MONDAY AS PRECIP EBBS AND THE SURGE OF
COLD/DRY AIR SUBSIDES. IN ADDITION...IT IS DIFFICULT TO GET
MEANINGFUL ICE ACCRUAL WITH FREEZING RAIN DURING THE DAYTIME HOURS
IN MID MARCH AT OUR LATITUDE. SO EXPECT MOST OF THE FREEZING RAIN
AND DRIZZLE TO FALL BETWEEN 4AM AND 9AM WITH ACCUMULATIONS GENERALLY
CONFINED TO ELEVATED SURFACES SUCH AS TREE TOPS IN THE COLDER AIR
ALOFT AND REMOVED FROM THE GROUND WHICH SHOULD BE RADIATING SOME
HEAT. LOWS MONDAY MORNING WILL RANGE FROM NEAR 30 AT THE VA BORDER
TO THE UPPER 30S TOWARD THE SC BORDER.
EXPECT PRECIPITATION TO BE RATHER LIGHT AND INTERMITTENT LATE MONDAY
AND MONDAY AFTERNOON AS DRYING ALOFT MOVES IN AND CENTRAL NC IS IN A
REGION OF WEAK RIDGING BETWEEN SYSTEMS. SENSIBLE WEATHER IS BEST
CHARACTERIZED AS CLOUDY SKIES WITH PERIODS OF LIGHT RAIN OR DRIZZLE
WITH POPS IN THE 30-40 PERCENT RANGE. TEMPERATURES SHOULD RECOVER
SLIGHTLY WITH THE ABSENCE OF WIDESPREAD RAIN AND SOME INSOLATION
THROUGH THE CLOUD COVER. HIGHS WILL RANGE IN THE 34 NEAR THE VA
BORDER TO THE LOWER 40S NEAR THE SC BORDER.
ANOTHER SURGE OF COLD AIR IS EXPECTED ON MONDAY NIGHT WITH SURFACE
TEMPERATURES GETTING EVEN COLDER THAN MONDAY MORNING. BOTH THE
GFS/ECMWF DRIVE THE WET BULB FREEZING LINE EVEN FURTHER SOUTH ACROSS
THE WESTERN PIEDMONT WITH THE ORIENTATION OF THE WBZ LINE SHIFTING
FROM WEST-EAST ON MONDAY MORNING TO MORE SOUTHWEST-NORTHEAST BY
TUESDAY MORNING. THE NAM REMAINS AN OUTLIER DURING THIS PERIOD AS IT
APPEARS TO GO BONKERS BY DEVELOPING AN INTENSE SURFACE LOW NEAR
SAVANNAH AND DRIVES THE LOW NORTHEAST ALONG THE CAROLINA COAST.
THERE IS ANOTHER PERIOD OF FREEZING RAIN AND EVEN SOME SLEET
POSSIBLE MONDAY NIGHT WITH THE ULTIMATE IMPACT DRIVEN NOT ONLY BY
THE MOUNT OF COLD AIR BUT MORE IMPORTANTLY BY THE QPF. GUIDANCE
DIFFERS WITH THE AMOUNT AND TIMING OF PRECIPITATION DURING THE
PERIOD BUT THERE WILL LIKELY BE AROUND 0.10 TO POSSIBLY 0.20 INCHES
OF LIQUID EQUIVALENT THAT FALLS ACROSS THE COLDER AND POTENTIALLY
WINTRY WEATHER AREA. LOWS TUESDAY MORNING SHOULD RANGE FROM NEAR 27
ACROSS THE FAR NORTHERN PARTS OF THE TRIAD TO MID 30S ACROSS THE
SOUTHEAST.
CONTINUED CLOUDY AND UNSETTLED ON TUESDAY AS BOTH THE GFS/ECMWF PUSH
A SURFACE WAVE AWAY FROM THE MID ATLANTIC WHILE THE NAM APPEARS LOST
BY DRIVING AN INTENSIFYING SURFACE WAVE INTO THE CHESAPEAKE BAY.
TEMPERATURES SHOULD RECOVER A BIT AND CLIMB ABOVE FREEZING
EVERYWHERE BY MID MORNING BEFORE HIGHS EVENTUALLY REACH THE 40-45
DEGREE RANGE. THE GREATEST CHANCE OF PRECIPITATION WILL OCCUR
ACROSS THE SOUTHEAST AHEAD OF THE SOUTHERN STREAM SHORT WAVE AND
CLOSER TO THE SURFACE WAVE.
THREE-DAY QPF VALUES RANGE FROM AROUND AN INCH NEAR THE VA BORDER TO
1.5 INCHES NEAR THE SC BORDER ALTHOUGH SOME GUIDANCE...ESPECIALLY
THE NAM/SREF ARE CONSIDERABLY HIGHER. MUCH OF THAT PRECIPITATION
ARRIVES SUNDAY AFTERNOON AND EVENING WITH GENERALLY LIGHTER AMOUNTS
EXPECTED FOR MONDAY AND TUESDAY. THESE AMOUNTS ARE LIKELY
INSUFFICIENT FOR A FLASH FLOOD OR AERIAL FLOOD WATCH. SEE THE
HYDROLOGY SECTION BELOW FOR MORE DETAILS. -BLAES
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 300 AM SUNDAY...
A LOT OF UNCERTAINTY STILL EXISTS IN THE LONG TERM. A SERIES OF
SHORTWAVES ARE EXPECTED TO MOVE THROUGH THE AREA AND THE GFS AND
ECMWF HANDLE THEM DIFFERENTLY WITH RESPECT TO TIMING...AMPLITUDE...
AND PRECIPITATION. IN GENERAL...THE ECMWF IS SLOWER...WETTER...AND
COOLER THAN THE GFS. ALTHOUGH THERE IS A DESCENT CHANCE THAT
PRECIPITATION WILL LINGER THROUGH THE DAY WEDNESDAY...IT SHOULD BE
ALL LIQUID AND FAIRLY LIGHT. GIVEN THE MODEL DISCREPANCIES AND
RESULTANT UNCERTAINTY...WILL MAINTAIN A MAINLY DRY FORECAST
WEDNESDAY NIGHT THROUGH SUNDAY...WITH THE EXCEPTION OF A SLIGHT
CHANCE FOR RAIN WITH THE FROPA ON SATURDAY. IN THE LOW LEVELS...THE
COLD AIR WEDGE...PRESENT IN BOTH MODELS OVER THE NORTHWEST...SHOULD
WEAKEN AS A FRONTAL BOUNDARY APPROACHES FROM THE WEST THURSDAY. A
WEAK SURFACE HIGH WILL MOVE THROUGH THE AREA BEHIND THE FRONT ON
FRIDAY...AHEAD OF THE NEXT FRONTAL SYSTEM TO THE WEST. BOTH MODELS
INDICATE THE COLD FRONT WITH THIS SYSTEM WILL PROGRESS THROUGH
CENTRAL NC SATURDAY EVE/NIGHT...ALTHOUGH THE SPEED AND ORIENTATION
DIFFER BETWEEN THE MODELS. HIGH PRESSURE IS AGAIN EXPECTED TO BUILD
IN BEHIND THE FRONT. HIGH TEMPERATURES WILL GENERALLY INCREASE
THROUGH SATURDAY...LOWEST IN THE NORTHWEST AND HIGHEST IN THE
SOUTHEAST.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 745 AM SUNDAY...
VFR CONDITIONS WILL CONTINUE THIS MORNING...AS CONTINENTAL POLAR
HIGH PRESSURE RIDGES SOUTHWARD FROM SOUTHERN CANADA. WARM AND MOIST
AIR FROM THE SOUTH WILL ASCEND THE HIGH PRESSURE AND ASSOCIATED
NORTHEASTERLY FLOW AT THE SURFACE AND RESULT IN THE DEVELOPMENT/
NORTHEASTWARD EXPANSION OF RAIN AND MVFR-IFR CONDITIONS BETWEEN 15-
21Z TODAY. ENE TO NE SURFACE WINDS WILL GRADUALLY INCREASE INTO THE
10-15 KT RANGE...AND BECOME GUSTY TO AROUND 20 KTS THIS AFTERNOON
AND TONIGHT...AS THE PRESSURE GRADIENT TIGHTENS BETWEEN THE SURFACE
HIGH AND LOW PRESSURE TRACKING ALONG THE COAST OF THE CAROLINAS.
MARGINAL LOW LEVEL WIND SHEAR CONDITIONS WILL ALSO BE POSSIBLE FOR A
BRIEF TIME AT KFAY THIS EVENING...WHERE WINDS AT 2000 FT MAY BRIEFLY
BECOME SOUTHEASTERLY AT 35 KTS (ATOP NORTHEASTERLY SURFACE FLOW).
PERIODS OF RAIN AND DRIZZLE - AND CONTINUED MVFR-IFR CONDITIONS -
WILL TRANSITION TO FREEZING RAIN AND FREEZING DRIZZLE BETWEEN 06Z-
09Z AT TRIAD TERMINALS...AND THIS CHANGEOVER WILL NEAR KRDU BY 12Z
MON...WITH CONTINUED LIQUID ELSEWHERE. THESE POOR AVIATION
CONDITIONS WILL THEN LIKELY CONTINUE THROUGH EARLY WED...AS ANOTHER
AREA OF LOW PRESSURE LIFTS UP THE SOUTHEAST COAST AND MAINTAINS THE
COLD AIR DAMMING REGIME OVER CENTRAL NC.
&&
.HYDROLOGY...
AS OF 1115 AM SUNDAY...
WITH FLASH FLOOD GUIDANCE STILL 2.5 INCHES OR GREATER FOR THREE
HOURS OR GREATER...WILL CONTINUE TO REFRAIN FROM ANY FLOOD WATCHES
GIVEN THE EXPECTED QPF. SHOULD NOTE THAT DEEP CONVECTION OVER THE
FAR SOUTHEAST CONUS MAY IMPACT SOME OF THE EXPECTED HIGHER RAINFALL
TOTALS OVER THE SANDHILLS AND COASTAL PLAIN OF CENTRAL NORTH
CAROLINA. CONSISTENTLY IT APPEARS THE PROBABILITY OF MINOR FLOOD
STAGE BEING REACHED IS HIGHEST AT SMITHFIELD WHERE A RIVER FLOOD
WARNING IS IN EFFECT...LESS SO AT CLAYTON...AND NOTICEABLY LOWER AT
OTHER MAINSTEM RIVER SITES EVEN BASED ON THE HIGHEST QPF AVAILABLE
ON THE ENSEMBLE RIVER LEVEL OUTPUT OF THE MMEFS.
&&
.CLIMATE...
THE RECORD LOW MAXIMUM TEMPERATURES FOR MARCH 17 (MONDAY) ARE...
KGSO...38 DEGREES FROM 2005.
KRDU...32 DEGREES FROM 1892.
KFAY...39 DEGREES FROM 2005.
THE RECORD LOW MAXIMUM TEMPERATURES FOR MARCH 18 (TUESDAY) ARE...
KGSO...36 DEGREES FROM 1961.
KRDU...36 DEGREES FROM 1892.
KFAY...41 DEGREES FROM 1998.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT
MONDAY FOR NCZ007>009-021>023.
&&
$$
SYNOPSIS...MWS
NEAR TERM...MWS/SMITH
SHORT TERM...BLAES
LONG TERM...KCP
AVIATION...MWS
CLIMATE...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1030 AM EDT SUN MAR 16 2014
.SYNOPSIS... AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE SOUTHERN
PLAINS TODAY AND THEN TRACK EASTWARD ALONG THE NORTHERN GULF COAST
STATES AND COASTAL CAROLINAS THROUGH TONIGHT.
&&
.NEAR TERM /TODAY/...
AS OF 1030 AM SUNDAY...
A WEAK COLD FRONT HAS DRIFTED SOUTH OF THE AREA AND ESSENTIALLY
WASHED OUT THIS MORNING...WITH A SECONDARY ARCTIC FRONT DRAPED
ACROSS SOUTH-CENTRAL VA. MEANWHILE...AN ELONGATED AND
COMPLEX...POSITIVELY TILED UPPER TROUGH IS EVOLVING OVER THE SOUTHERN
PLAINS...WITH A LEAD SHORTWAVE AND ASSOCIATED 1002MB SURFACE LOW
KICKING NORTHEAST ACROSS THE LOWER/MID MS RIVER VALLEY REGION. AND
EXPANSIVE PRECIP SHIELD IS SPREAD ACROSS GA/SC AND INTO SOUTHWESTERN
NC...WITH MEASURABLE PRECIP NOW ONT HE DOORSTEPS OF THE SOUTHERN
PIEDMONT. WHILE LARGE SCALE FORCING...WEAK HEIGHT FALLS AND WARM
ADVECTION....WILL DRIVE PRECIP ACROSS THE AREA TODAY...THERE ARE TWO
MAIN CONCERNS EVOLVING IN THE UPSTREAM RADAR/SATELLITE OBS: 1) A DRY
SLOT SURGING ACROSS NORTHERN AL AND TN AND 2) THE
ORIENTATION/TRACK OF CONVECTION ACROSS THE GULF COAST STATES.
ISENTROPIC LIFT WILL BE MAXIMIZED ACROSS CENTRAL NC BETWEEN 18Z AND
00Z...WHICH IS WHEN CONFIDENCE IN HIGHEST POPS/QPF OCCURS. THE DRY
SLOT MAY HELP TO CUT DOWN ON PRECIP RATES ACROSS WESTERN PORTION
OF THE AREA BY AS EARLY AS 21Z...WHILE THE GULF COAST CONVECTION
MAY ACT TO DIRECT THE BEST LOW-LEVEL JETTING AND WARM ADVECTION
TOWARD THE CAROLINA COASTAL AREAS. THE LATEST RAP QPF AND HRRR
SIMULATED REFLECTIVITY HINT AT THIS...WITH THE AXIS OF HEAVIEST
PRECIP ACROSS CENTRAL SC AND EASTERN NC. HAVE ADJUST POPS PRIOR TO
NOON TO REFLECT CURRENT RADAR TRENDS...WITH CATEGORICAL STILL AFTER
NOON. MINOR ADJUSTMENTS TO QPF LEAD TO NEAR AND INCH IN THE FAR
SOUTH AND ONE HALF INCH ACROSS THE NORTH.
TEMPS ARE LIKELY REACHING THEIR HIGHS FOR TODAY...MOSTLY IN THE 50S
AREAWIDE. EVAPORATIVE COOLING AND SLOWLY STRENGTHENING COLD
ADVECTION FROM THE NORTH...AS A SURFACE WAVE BEGINS TO DEVELOP
OFFSHORE...WILL CAUSE TEMPS TO HOLD STEADY OR FALL INTO THE 40S
(MAINLY NORTH) THIS AFTERNOON.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AS OF 320 AM SUNDAY...
...WINTER WEATHER ADVISORY FOR MAINLY MINOR ACCUMULATIONS OF
FREEZING RAIN WILL BE ISSUED FOR MIDNIGHT TO NOON MONDAY FOR
LOCATIONS NEAR AND NORTH OF INTERSTATE 85...
DIFFICULT FORECAST DURING THIS PERIOD AS THERE CONTINUES TO BE SOME
SIGNIFICANT DIFFERENCES IN THE NWP GUIDANCE...ESPECIALLY FOR THE
MONDAY INTO TUESDAY TIME FRAME. THE END RESULT IS A COMPLEX AND BUSY
FORECAST WITH DIFFERING IMPACTS...MOST OF WHICH WILL BE MINOR TO
MODERATE.
WIDESPREAD RAIN WILL BE ONGOING THIS EVENING AT THE START OF THE
SHORT TERM PERIOD AS A SURGE IN LOW LEVEL WARM ADVECTION
PRECIPITATION ENHANCED BY THE RIGHT ENTRANCE REGION OF A 125KT UPPER
LEVEL JET ACROSS THE MID ATLANTIC. AT THE SAME TIME A BACK DOOR COLD
FRONT WILL PUSH SOUTH INTO CENTRAL NC WITH A PUSH OF CONSIDERABLY
COLDER AND DRIER AIR AT THE SURFACE. PRECIPITATION COVERAGE AND
INTENSITY WILL WANE CONSIDERABLY LATE IN THE EVENING AND OVERNIGHT
AS THE BEST FORCING LIFTS NORTHEAST OF THE AREA AND AS THE MID/UPPER
LEVELS DRY OUT. LIGHT QPF AMOUNTS ON THE ORDER OF .10 INCHES WEST TO
.15 INCHES EAST ARE EXPECTED AFTER MIDNIGHT. GUIDANCE DIFFERS WITH
THE STRENGTH OF THE SURFACE BASED COLD AIR OVER CENTRAL NC. THE NAM
IS CONSIDERABLY COLDER...LIKELY AS A RESULT OF THE SLIGHTLY STRONGER
AND FURTHER SOUTH PLACEMENT OF THE MODERATELY STRONG SURFACE HIGH
WHICH PROVIDES A CLOSER COLD AIR SOURCE REGION AND WHICH DEVELOPS A
SLIGHTLY STRONGER PRESSURE GRADIENT TO PUSH THE COLD/DRY AIR FURTHER
SOUTH. USED A BLEND OF GFS/ECMWF GUIDANCE TO PRODUCE SURFACE
TEMPERATURES WHICH FALL TO FREEZING AT AROUND 3 TO 4 AM NEAR THE VA
BORDER. THE NAM GIVES A SFC TEMP OF 26 AT KGSO AT 8AM WHILE THE GFS
GIVES A COLD BUT MORE REASONABLE 29. THE 32 DEGREE SFC TEMP LINE
REACHES AS FAR SOUTH AS LOUISBURG....DURHAM AND HIGH POINT MONDAY
MORNING WITH SUBFREEZING TEMPS FURTHER NORTH. MOST OF THE
PRECIPITATION SHOULD FALL AS FREEZING RAIN OR FREEZING DRIZZLE WITH
A BRIEF PERIOD OF SLEET POSSIBLE WHEN MOISTURE IS STILL SUFFICIENTLY
DEEP ENOUGH FOR ICE ALOFT. WITH THIS IN MIND...WILL ISSUE A WINTER
WEATHER ADVISORY FROM MIDNIGHT THROUGH NOON MONDAY FOR OUR NORTHERN
TIER OF COUNTIES...MAINLY NORTH OF INTERSTATE 95. SURFACE
TEMPERATURES RECOVER A BIT ON MONDAY AS PRECIP EBBS AND THE SURGE OF
COLD/DRY AIR SUBSIDES. IN ADDITION...IT IS DIFFICULT TO GET
MEANINGFUL ICE ACCRUAL WITH FREEZING RAIN DURING THE DAYTIME HOURS
IN MID MARCH AT OUR LATITUDE. SO EXPECT MOST OF THE FREEZING RAIN
AND DRIZZLE TO FALL BETWEEN 4AM AND 9AM WITH ACCUMULATIONS GENERALLY
CONFINED TO ELEVATED SURFACES SUCH AS TREE TOPS IN THE COLDER AIR
ALOFT AND REMOVED FROM THE GROUND WHICH SHOULD BE RADIATING SOME
HEAT. LOWS MONDAY MORNING WILL RANGE FROM NEAR 30 AT THE VA BORDER
TO THE UPPER 30S TOWARD THE SC BORDER.
EXPECT PRECIPITATION TO BE RATHER LIGHT AND INTERMITTENT LATE MONDAY
AND MONDAY AFTERNOON AS DRYING ALOFT MOVES IN AND CENTRAL NC IS IN A
REGION OF WEAK RIDGING BETWEEN SYSTEMS. SENSIBLE WEATHER IS BEST
CHARACTERIZED AS CLOUDY SKIES WITH PERIODS OF LIGHT RAIN OR DRIZZLE
WITH POPS IN THE 30-40 PERCENT RANGE. TEMPERATURES SHOULD RECOVER
SLIGHTLY WITH THE ABSENCE OF WIDESPREAD RAIN AND SOME INSOLATION
THROUGH THE CLOUD COVER. HIGHS WILL RANGE IN THE 34 NEAR THE VA
BORDER TO THE LOWER 40S NEAR THE SC BORDER.
ANOTHER SURGE OF COLD AIR IS EXPECTED ON MONDAY NIGHT WITH SURFACE
TEMPERATURES GETTING EVEN COLDER THAN MONDAY MORNING. BOTH THE
GFS/ECMWF DRIVE THE WET BULB FREEZING LINE EVEN FURTHER SOUTH ACROSS
THE WESTERN PIEDMONT WITH THE ORIENTATION OF THE WBZ LINE SHIFTING
FROM WEST-EAST ON MONDAY MORNING TO MORE SOUTHWEST-NORTHEAST BY
TUESDAY MORNING. THE NAM REMAINS AN OUTLIER DURING THIS PERIOD AS IT
APPEARS TO GO BONKERS BY DEVELOPING AN INTENSE SURFACE LOW NEAR
SAVANNAH AND DRIVES THE LOW NORTHEAST ALONG THE CAROLINA COAST.
THERE IS ANOTHER PERIOD OF FREEZING RAIN AND EVEN SOME SLEET
POSSIBLE MONDAY NIGHT WITH THE ULTIMATE IMPACT DRIVEN NOT ONLY BY
THE MOUNT OF COLD AIR BUT MORE IMPORTANTLY BY THE QPF. GUIDANCE
DIFFERS WITH THE AMOUNT AND TIMING OF PRECIPITATION DURING THE
PERIOD BUT THERE WILL LIKELY BE AROUND 0.10 TO POSSIBLY 0.20 INCHES
OF LIQUID EQUIVALENT THAT FALLS ACROSS THE COLDER AND POTENTIALLY
WINTRY WEATHER AREA. LOWS TUESDAY MORNING SHOULD RANGE FROM NEAR 27
ACROSS THE FAR NORTHERN PARTS OF THE TRIAD TO MID 30S ACROSS THE
SOUTHEAST.
CONTINUED CLOUDY AND UNSETTLED ON TUESDAY AS BOTH THE GFS/ECMWF PUSH
A SURFACE WAVE AWAY FROM THE MID ATLANTIC WHILE THE NAM APPEARS LOST
BY DRIVING AN INTENSIFYING SURFACE WAVE INTO THE CHESAPEAKE BAY.
TEMPERATURES SHOULD RECOVER A BIT AND CLIMB ABOVE FREEZING
EVERYWHERE BY MID MORNING BEFORE HIGHS EVENTUALLY REACH THE 40-45
DEGREE RANGE. THE GREATEST CHANCE OF PRECIPITATION WILL OCCUR
ACROSS THE SOUTHEAST AHEAD OF THE SOUTHERN STREAM SHORT WAVE AND
CLOSER TO THE SURFACE WAVE.
THREE-DAY QPF VALUES RANGE FROM AROUND AN INCH NEAR THE VA BORDER TO
1.5 INCHES NEAR THE SC BORDER ALTHOUGH SOME GUIDANCE...ESPECIALLY
THE NAM/SREF ARE CONSIDERABLY HIGHER. MUCH OF THAT PRECIPITATION
ARRIVES SUNDAY AFTERNOON AND EVENING WITH GENERALLY LIGHTER AMOUNTS
EXPECTED FOR MONDAY AND TUESDAY. THESE AMOUNTS ARE LIKELY
INSUFFICIENT FOR A FLASH FLOOD OR AERIAL FLOOD WATCH. SEE THE
HYDROLOGY SECTION BELOW FOR MORE DETAILS. -BLAES
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 300 AM SUNDAY...
A LOT OF UNCERTAINTY STILL EXISTS IN THE LONG TERM. A SERIES OF
SHORTWAVES ARE EXPECTED TO MOVE THROUGH THE AREA AND THE GFS AND
ECMWF HANDLE THEM DIFFERENTLY WITH RESPECT TO TIMING...AMPLITUDE...
AND PRECIPITATION. IN GENERAL...THE ECMWF IS SLOWER...WETTER...AND
COOLER THAN THE GFS. ALTHOUGH THERE IS A DESCENT CHANCE THAT
PRECIPITATION WILL LINGER THROUGH THE DAY WEDNESDAY...IT SHOULD BE
ALL LIQUID AND FAIRLY LIGHT. GIVEN THE MODEL DISCREPANCIES AND
RESULTANT UNCERTAINTY...WILL MAINTAIN A MAINLY DRY FORECAST
WEDNESDAY NIGHT THROUGH SUNDAY...WITH THE EXCEPTION OF A SLIGHT
CHANCE FOR RAIN WITH THE FROPA ON SATURDAY. IN THE LOW LEVELS...THE
COLD AIR WEDGE...PRESENT IN BOTH MODELS OVER THE NORTHWEST...SHOULD
WEAKEN AS A FRONTAL BOUNDARY APPROACHES FROM THE WEST THURSDAY. A
WEAK SURFACE HIGH WILL MOVE THROUGH THE AREA BEHIND THE FRONT ON
FRIDAY...AHEAD OF THE NEXT FRONTAL SYSTEM TO THE WEST. BOTH MODELS
INDICATE THE COLD FRONT WITH THIS SYSTEM WILL PROGRESS THROUGH
CENTRAL NC SATURDAY EVE/NIGHT...ALTHOUGH THE SPEED AND ORIENTATION
DIFFER BETWEEN THE MODELS. HIGH PRESSURE IS AGAIN EXPECTED TO BUILD
IN BEHIND THE FRONT. HIGH TEMPERATURES WILL GENERALLY INCREASE
THROUGH SATURDAY...LOWEST IN THE NORTHWEST AND HIGHEST IN THE
SOUTHEAST.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 745 AM SUNDAY...
VFR CONDITIONS WILL CONTINUE THIS MORNING...AS CONTINENTAL POLAR
HIGH PRESSURE RIDGES SOUTHWARD FROM SOUTHERN CANADA. WARM AND MOIST
AIR FROM THE SOUTH WILL ASCEND THE HIGH PRESSURE AND ASSOCIATED
NORTHEASTERLY FLOW AT THE SURFACE AND RESULT IN THE DEVELOPMENT/
NORTHEASTWARD EXPANSION OF RAIN AND MVFR-IFR CONDITIONS BETWEEN 15-
21Z TODAY. ENE TO NE SURFACE WINDS WILL GRADUALLY INCREASE INTO THE
10-15 KT RANGE...AND BECOME GUSTY TO AROUND 20 KTS THIS AFTERNOON
AND TONIGHT...AS THE PRESSURE GRADIENT TIGHTENS BETWEEN THE SURFACE
HIGH AND LOW PRESSURE TRACKING ALONG THE COAST OF THE CAROLINAS.
MARGINAL LOW LEVEL WIND SHEAR CONDITIONS WILL ALSO BE POSSIBLE FOR A
BRIEF TIME AT KFAY THIS EVENING...WHERE WINDS AT 2000 FT MAY BRIEFLY
BECOME SOUTHEASTERLY AT 35 KTS (ATOP NORTHEASTERLY SURFACE FLOW).
PERIODS OF RAIN AND DRIZZLE - AND CONTINUED MVFR-IFR CONDITIONS -
WILL TRANSITION TO FREEZING RAIN AND FREEZING DRIZZLE BETWEEN 06Z-
09Z AT TRIAD TERMINALS...AND THIS CHANGEOVER WILL NEAR KRDU BY 12Z
MON...WITH CONTINUED LIQUID ELSEWHERE. THESE POOR AVIATION
CONDITIONS WILL THEN LIKELY CONTINUE THROUGH EARLY WED...AS ANOTHER
AREA OF LOW PRESSURE LIFTS UP THE SOUTHEAST COAST AND MAINTAINS THE
COLD AIR DAMMING REGIME OVER CENTRAL NC.
&&
.HYDROLOGY...
AS OF 420 AM SUNDAY...
THREE-DAY QPF VALUES WILL RANGE FROM AROUND AN INCH NEAR THE VA
BORDER TO 1.5 INCHES NEAR THE SC BORDER ALTHOUGH SOME
GUIDANCE SUGGESTS THAT AMOUNTS COULD BE CONSIDERABLY HIGHER. MUCH
OF THE PRECIPITATION WILL ARRIVE TODAY AND TONIGHT WITH GENERALLY
LIGHTER AMOUNTS EXPECTED FOR MONDAY AND TUESDAY. FLASH FLOOD
GUIDANCE FOR A SIX HOUR PERIOD RANGES FROM 2.8 TO 4.1 INCHES WITH
THE HIGHER VALUES ACROSS THE SOUTHEASTERN PART OF THE HSA WHERE
THE HEAVIER RAIN IS EXPECTED. PROJECTED RAINFALL APPEARS INSUFFICIENT
FOR A FLASH FLOOD WATCH WITH THE POTENTIAL FOR AERIAL FLOODING
ALSO LIMITED.
BASED ON THE QPF NOTED ABOVE...SIGNIFICANT RISES ARE EXPECTED ON
THE MAIN STEM RIVERS. IT APPEARS THAT THE GREATEST POTENTIAL FOR
MINOR FLOODING WILL BE ALONG WITH NEUSE RIVER...ESPECIALLY AT
SMITHFIELD AND POSSIBLY CLAYTON. SIGNIFICANT RISES ARE POSSIBLE
ON THE TAR RIVER BUT THE POTENTIAL FOR FLOODING IS MUCH LESS.
-BLAES
&&
.CLIMATE...
THE RECORD LOW MAXIMUM TEMPERATURES FOR MARCH 17 ARE...
KGSO...38 DEGREES FROM 2005.
KRDU...32 DEGREES FROM 1892.
KFAY...39 DEGREES FROM 2005.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT
MONDAY FOR NCZ007>009-021>023.
&&
$$
SYNOPSIS...MWS
NEAR TERM...MWS/SMITH
SHORT TERM...BLAES
LONG TERM...KCP
AVIATION...MWS
HYDROLOGY...BLAES
CLIMATE...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
222 AM EDT SUN MAR 16 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL SETTLE SOUTH THROUGH THE CAROLINAS
TONIGHT. MEANWHILE...AN AREA OF LOW PRESSURE WILL DEVELOP OVER
THE SOUTHERN PLAINS AND THEN TRACK EASTWARD ALONG THE NORTHERN
GULF COAST STATES AND COASTAL CAROLINAS SUNDAY AND SUNDAY NIGHT.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
AS OF 855 PM SATURDAY...
LATEST SURFACE ANALYSIS SHOWS A WEAK BOUNDARY...MAINLY DENOTED BY A
WIND SHIFT TO NW AND ABOUT A 5-10 DEG DEWPOINT DROP...ALONG A KFVX-
KDAN-KHKY LINE. THIS BOUNDARY IS PROGGED BY THE LATEST HRRR TO
CONTINUE DRIFTING SOUTH OVERNIGHT...BUT HAVING LITTLE OR NO IMPACT
ON OUR SENSIBLE WEATHER DURING THAT TIME. OTHERWISE...MID AND HIGH
CLOUDS WILL CONTINUE TO THICKEN AND LOWER OVERNIGHT AHEAD OF THE
STORM SYSTEM TO OUR WEST. THIS WILL IMPACT OUR TEMP TREND
OVERNIGHT...WITH LIMITED IF ANY RADIATIONAL COOLING THE REST OF THE
NIGHT. BOTH MAV AND MET GUIDANCE WAS ABOUT 2-4 DEG TOO COLD FOR ITS
00Z PROG. THUS MAKING APPROPRIATE ADJUSTMENTS SUGGESTS LOWS TONIGHT
BOTTOMING OUT IN MID-UPR 40S...COLDEST NORTH. WILL MAKE A FEW
SUBTLE TWEAKS TO THE TEMP GRIDS FOR OVERNIGHT...OTHERWISE...REST OF
THE 1ST PERIOD FORECAST LOOKS GOOD FOR THE EVENING UPDATE.
SUNDAY AND SUNDAY NIGHT...
THE UPPER TROUGH TO OUR WEST WILL UNDERGO A SLOW EVOLUTION OVER THE
NEXT COUPLE OF DAYS...BECOMING ELONGATED AND POSITIVELY TILTED WEST
OF THE APPALACHIANS. A SURFACE LOW IS FORECAST TO MOVE TOWARD THE
TN VALLEY ON SUNDAY...WITH A SECONDARY LOW DEVELOPING OFF THE
CAROLINA COAST SUNDAY NIGHT. PRECIPITATION...MOSTLY FOCUSED ALONG
AN 850MB FRONT TO OUR SOUTH SUNDAY MORNING...WILL OVERSPREAD THE
AREA FROM SOUTHWEST TO NORTHEAST DURING THE DAY AS THE FRONT PUSHES
NORTH AND ISENTROPIC LIFT INCREASES ATOP A WEAK IN-SITU CAD AIRMASS.
PRECIPITABLE WATER PEAKS AROUND 1.3 INCHES AND A ROUGH MODEL
CONSENSUS GIVE 1 TO 1.25 INCHES OF QPF THROUGH 06Z...GREATEST
ACROSS THE SOUTH AND WEST. MID-LEVEL LAPSE RATES ARE FAIRLY WEAK
THROUGH THE PERIOD..SO ELEVATED CONVECTION DOES APPEAR TO BE AN
ISSUE...WITH ALL LOW-LEVEL BASED INSTABILITY OFFSHORE. HAVE
HIGHLIGHTED THE POTENTIAL FOR MINOR RIVER FLOODING...MAINLY ALONG
THE NEUSE...IN THE HYDROLOGY SECTION BELOW.
TEMPS ARE TRICKY AND WILL FOLLOW A NON-DIURNAL CURVE WITH BEST HEAT
ACROSS THE NORTH PRIOR TO THE ARRIVAL OF LOWER CLOUD BASES AND
PRECIP. EXPECT TEMPS TO REACH THE LOW TO MID 50S ACROSS THE NORTH
EARLY ON...WITH MID 40S NORTHWEST AND UPPER 40S POSSIBLE IN THE
NORTH.
THE FORECAST BECOMES EXTRA TRICKY SUNDAY NIGHT AS A SECONDARY
FRONT AND LEADING EDGE OF A CANADIAN AIRMASS PUSHES INTO NC FROM
THE NORTH. THE PARENT SURFACE HIGH...WHILE NOT VERY STRONG
(1025MB)...WILL SETTLE TOWARD UPSTATE NY...AND ALL MODELS HAVE
TRENDED COLDER WITH BOUNDARY LAYER TEMP PROFILES BETWEEN 06 AND
12Z MONDAY MORNING. THE SURFACE WETBULB FREEZING LINE IS FORECAST
TO PUSH INTO THE NORTHWEST AND NORTHERN PIEDMONT AREAS BETWEEN 06Z
AND 09Z...REACHING ROUGHLY A LING FROM DAVIDSON TO ORANGE TO VANCE
COUNTIES BY 12Z. THE BIGGEST UNCERTAINTY DURING THIS TIME FRAME
WILL BE QPF AS A DRY SLOT PUNCHES NORTHEAST ACROSS THE AREA...ICE
NUCLEATION IS LOST...AND PRECIP RATES FALL OFF TREMENDOUSLY. A TOP
DOWN APPROACH WOULD FAVOR RAIN CHANGING TO FREEZING RAIN AND
DRIZZLE BY 12Z....WITHOUT A SIGNIFICANTLY COLD ENOUGH COLD NOSE
FOR MORE THAN A BRIEF PERIOD OF SLEET DURING THE TRANSITION...WHEN
MOISTURE IS STILL SUFFICIENTLY DEEP ENOUGH FOR ICE ALOFT. WITH
MODELS SHOWING ONLY A FEW HUNDREDTHS OF QPF...ITS DIFFICULT TO
HAVE MUCH CONFIDENCE IN SIGNIFICANT ICE ACCRUAL...BUT AN ADVISORY
MAY BE NEEDED. POPS WILL REMAIN IN THE LIKELY CATEGORY BECAUSE
MOST AREAS WILL CONTINUE TO SEE SOME FORM OF LIGHT PRECIP...BUT
ACCUMULATION WILL BE VERY LIGHT. LOWS 31-32 IN THE AREAS MENTIONED
FOR FREEZING RAIN AND 33- 40 TO THE SOUTH AND EAST.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
AS OF 300 PM SATURDAY...
BY MONDAY MORNING...BOTH THE GFS AND THE NAM FORECAST DRYING IN THE
MID-LEVELS MOVING INTO CENTRAL NORTH CAROLINA. HUMIDITIES ARE
LIMITED ABOVE THE MOIST BOUNDARY LAYER TO NEAR -10C...WHICH MAY MAKE
ICE NUCLEATION DIFFICULT FOR SUBSTANTIAL PRECIPITATION FOR MUCH OF
THE DAY. IF THIS OCCURS...WHILE THE SURFACE WET BULB TEMPERATURE IS
BELOW 0C FOR MUCH OF THE DAY IN THE NORTHWEST PIEDMONT IN
PARTICULAR...THE PRECIPITATION RATES MAY BE LIGHT. THE LATEST WRF
GUIDANCE SUGGESTS THIS...AND QPF FROM THE GFS AND THE NAM IS LIGHT
FOR THE DAY ON MONDAY. ASSUMING THE QPF IS ACCURATE...THIS IS
FORTUNATE AS IF THE PRECIPITATION RATES WERE HIGHER...WITH A GOOD
COLD NOSE IN PLACE...JUST A LITTLE MORE SATURATION COULD RESULT IN
TEMPERATURES COOLING TO THE WET BULB AND STAYING THERE...AND THE
PRECIPITATION TYPE THROUGHOUT THE DAY WOULD ALMOST CERTAINLY BE NON-
LIQUID. HOWEVER...DESPITE A CLOUDY DAY AND A NORTHEAST FLOW...IF
PRECIPITATION RATES WANE AS EXPECTED...TEMPERATURES MAY BE ABLE TO
RISE EVEN A LITTLE BIT...AND LOWER PRECIPITATION RATES WOULD MEAN
MORE OF A LIGHT RAIN OR LIGHT DRIZZLE WITH SOME PATCHY SLEET OUTSIDE
OF LIGHT FREEZING RAIN IN THE MORNING WHERE TEMPERATURES ARE BELOW
FREEZING. FOR THE SENSIBLE WEATHER MONDAY WILL ONLY SHOW LIQUID
MAINLY SOUTH OF A LINE FROM ABOUT ALBEMARLE TO WILSON...WITH A
CHANCE OF A WINTRY MIX NORTH OF THIS LINE THROUGHOUT THE DAY. WILL
GO WITH LIKELY POPS FOR THE DAY AS A WHOLE...THOUGH EXPECT THERE
WILL BE PERIODS OF DRY CONDITIONS OR...AGAIN...JUST LIGHT
PRECIPITATION. DAYTIME HIGHS CERTAINLY WELL BELOW NORMAL...ONLY MID
TO UPPER 30S NORTH OF U.S. 64...AND NEAR 40 TO 45 FROM THERE SOUTH.
THE FORECAST MONDAY NIGHT IS ALSO QPF DEPENDENT...AND WHILE THE NAM
IS DRIER...THE GFS AND THE NEW ECMWF ARE NOTICEABLY WETTER...WITH AS
MUCH AS A QUARTER-INCH OF QPF OVERNIGHT MONDAY AS THE UPPER TROUGH
APPROACHES CENTRAL NORTH CAROLINA FROM THE WEST. IF THIS TREND
CONTINUES...GIVEN THE TEMPERATURE PROFILE ALOFT THIS COULD BE THE
PERIOD WHERE PRECIPITATION TYPE PROBLEMS COULD BE MOST ACUTE...
ESPECIALLY FROM THE TRIANGLE WEST AND NORTH. THIS WOULD ALSO BE A
SLIGHTLY MORE FAVORABLE TIME FOR CONCERN DUE TO THE TIME OF DAY...OR
NIGHT. LOW TEMPERATURES IN THAT AREA ARE FORECAST A COUPLE OF
DEGREES BELOW FREEZING OR SO... AND THE BUFR SOUNDINGS ARE STILL
COLD...YIELDING A LIKELIHOOD OF NON-LIQUID PRECIPITATION AS SURFACE
WET BULB TEMPERATURES THERE CONTINUE TO BE BELOW 0C. WHILE AN
ADVISORY-TYPE SCENARIO OVERALL IS PREFERRED AT PRESENT AS THE EVENT
DRAWS NEAR...IF THERE WAS ONE PERIOD IN THIS PART OF THE FORECAST
WHERE WINTER WEATHER HEADLINES MAY NEED TO BE RAISED A
CATEGORY...THIS COULD BE THE ONE. PRUDENT TO SEE HOW GUIDANCE TRENDS
REGARDING THIS FIFTH PERIOD FORECAST FOR NOW.
ON TUESDAY...WET BULB TEMPERATURES AND 1000-850MB THICKNESSES SHOULD
GRADUALLY RISE AS SURFACE LOW PRESSURE STARTS TO MOVE NORTH ALONG
THE CAROLINA COAST...AND COLD SURFACE HIGH PRESSURE STARTS TO
RETREAT. FOR THIS FORECAST CONFINED ANY PRECIPITATION-TYPE ISSUES TO
EARLY IN THE DAY...NOTING BY LATE MORNING ONLY LIQUID PRECIPITATION
IN CENTRAL NORTH CAROLINA. MORE CONFIDENT IN LIKELY CHANCES TO START
THE DAY...THEN DEPENDING ON THE TRACK AND SPEED OF LOW PRESSURE OFF
OF THE COAST...DIMINISHED POPS TO CHANCE BY LATE IN THE DAY...THOUGH
AT A MINIMUM IT SHOULD STILL BE CLOUDY AND DAMP. HIGHS AROUND 40 IN
THE NORTHWEST PIEDMONT...TO AROUND 50 IN THE FAR SOUTHEAST...LEANING
TOWARD THE ECMWF MOS MEAN TEMPERATURE GUIDANCE THEN.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...
FOR MUCH OF THIS PERIOD...IN GENERAL...THE GFS IS THE MORE
PROGRESSIVE MODEL WITH SURFACE AND UPPER-LEVEL FEATURES...WHILE THE
ECMWF IS MORE AMPLIFIED AND SLOWER. BOTH MODELS...HOWEVER...SUGGEST
SURFACE HIGH PRESSURE BEGINNING TO RETREAT LATE TUESDAY INTO
WEDNESDAY...SUCH THAT AS SURFACE LOW PRESSURE REMAINS NEAR THE
CAROLINA COAST...AND LOW-LEVEL MOISTURE LINGERS...1000-850MB
THICKNESSES RISE OVERNIGHT AND MODEL SOUNDINGS SUGGEST WARMING AS
WELL. WET BULB SURFACE TEMPERATURES AFTER 00Z WEDNESDAY ON BOTH
MODELS REMAIN 35F OR ABOVE...ALSO SUGGESTIVE THAT LINGERING
PRECIPITATION TUESDAY NIGHT INTO WEDNESDAY SHOULD BE LIQUID. MOST
PRECIPITATION THAT OCCURS SHOULD BE LIGHT...AS THE MID LEVELS ARE
CURRENTLY FORECAST TO BE RATHER DRY...AND WHAT MAY BE THE SENSIBLE
WEATHER RESULT OVER MOST OF CENTRAL NORTH CAROLINA IS PATCHES OF
LIGHT RAIN AND AREAS OF DRIZZLE. HOW MUCH CLEARING TAKES PLACE
WEDNESDAY IS SOMEWHAT UNCERTAIN GIVEN THE SLOWER EASTWARD PROGRESS
OF THE ECMWF AND DRIER AIR...BUT FOR THIS FORECAST WILL MENTION
SMALL CHANCES OF RAIN WEDNESDAY MORNING FOLLOWED BY DRY CONDITIONS
BY WEDNESDAY AFTERNOON USING A BLEND OF THE GFS AND ECMWF. HAVE
TRENDED TEMPERATURES COLDER WEDNESDAY FOR THIS FORECAST ANTICIPATING
MORE CLOUDS AT LEAST THROUGH THE FIRST HALF OF THE DAY...IN A
RELATIVE SENSE WARMEST SOUTHWEST INTO THE MID 60S WHERE ANY CLEARING
SHOULD TAKE PLACE EARLIEST.
FRONTAL TIMING REMAINS DIFFERENT ON THE GFS AND ECMWF WITH THE GFS
BRINGING A FRONT THROUGH DRY WEDNESDAY EVENING...AND THE ECMWF
BRINGING A FRONT THROUGH MOSTLY DRY DURING THURSDAY. THESE SOLUTIONS
ARE FAIRLY CONSISTENT WITH THE PREVIOUS RUNS OF THE INDIVIDUAL
MODELS...ALBEIT DRIER. SURFACE RIDGING OVER THE GULF SHOULD LIMIT
MOISTURE RETURN...ALTHOUGH THE ECMWF DOES HAVE QPF FROM THE COASTAL
PLAIN TOWARD THE COAST THURSDAY AFTERNOON LIKELY AS THE FRONT WITH
ITS ECMWF TIMING INTERACTS WITH A LITTLE MORE AVAILABLE MOISTURE AND
INSTABILITY TOWARD THE COAST. FOR THIS FORECAST...WILL SHOW DRY
CONDITIONS ESPECIALLY GIVEN THE GENERAL STABILITY OF THE COARSE
ECMWF MODEL SOUNDINGS...AND THE DRY AND STABLE GFS SOUNDINGS...
THOUGH AN ALTERNATIVE COULD BE A SMALL CHANCE OF SHOWERS MAINLY EAST
OF U.S. 1 WITH THE FRONTAL PASSAGE THURSDAY IF THE ECMWF VERIFIES
EXACTLY. THURSDAY COULD END UP BEING MODESTLY BREEZY...BUT THE
SURFACE DEW POINTS AS CURRENTLY FORECAST SHOULD KEEP ANY INCREASED
FIRE DANGER CONCERNS NEGLIGIBLE.
AT THE END OF THE PERIOD...THE ECMWF IS ACTUALLY A LITTLE MORE
PROGRESSIVE WITH THE APPROACH OF A SURFACE FRONT TRAILING A STRONG
SURFACE LOW MOVING THROUGH THE GREAT LAKES. SURFACE RIDGING ALONG
THE GULF DIMINISHES MORE ON THE GFS THAN THE ECMWF...SUCH THAT WHILE
THE ECMWF IS FAIRLY DRY WITH THE FRONTAL PASSAGE THE GFS ADVECTS
MORE MOISTURE NORTHWARD AND DEVELOPS A BETTER CHANCE FOR SHOWERS
DURING THE DAY SATURDAY...AND INTO SATURDAY NIGHT. WILL FORECAST
BROAD SLIGHT CHANCES FOR SHOWERS THROUGHOUT CENTRAL NORTH CAROLINA
SATURDAY DUE TO THE UNCERTAINTY OUT TO THE SEVENTH DAY...BUT A
PLAUSIBLE SCENARIO IS THAT MUCH OF THE DAY IS DRY...BREEZY AND WARM
AHEAD OF THE SURFACE FRONT...WITH SCATTERED SHOWERS POSSIBLE FROM
NORTHWEST TO SOUTHEAST IMMEDIATELY IN VICINITY OF THE FRONT AS IT
MOVES SOUTHEAST.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 215 AM SUNDAY...
VFR CONDITIONS WILL CONTINUE THIS MORNING...AS CONTINENTAL POLAR
HIGH PRESSURE RIDGES SOUTHWARD FROM SOUTHERN CANADA. WARM AND MOIST
AIR FROM THE SOUTH WILL ASCEND THE HIGH PRESSURE AND ASSOCIATED
NORTHEASTERLY FLOW AT THE SURFACE AND RESULT IN THE DEVELOPMENT/
NORTHEASTWARD EXPANSION OF RAIN AND MVFR-IFR CONDITIONS BETWEEN 16-
22Z TODAY. ENE TO NE SURFACE WINDS WILL GRADUALLY INCREASE INTO THE
10-15 KT RANGE...AND BECOME GUSTY TO AROUND 20 KTS TONIGHT...AS THE
PRESSURE GRADIENT TIGHTENS BETWEEN THE SURFACE HIGH AND LOW PRESSURE
TRACKING ALONG THE COAST OF THE CAROLINAS. MARGINAL LOW LEVEL WIND
SHEAR CONDITIONS WILL ALSO BE POSSIBLE TONIGHT.
PERIODS OF RAIN AND DRIZZLE - AND CONTINUED MVFR-IFR CONDITIONS -
WILL TRANSITION TO FREEZING RAIN AND FREEZING DRIZZLE AROUND THE END
OF THE 06Z TAF PERIOD AT TRIAD TERMINALS...AND THIS CHANGEOVER WILL
NEAR KRDU BY 12Z MON...WITH CONTINUED LIQUID ELSEWHERE. THESE
CONDITIONS WILL THEN LIKELY CONTINUE THROUGH TUESDAY NIGHT...AS
ANOTHER AREA OF LOW PRESSURE LIFTS UP THE SOUTHEAST COAST.
&&
.HYDROLOGY...
AS OF 300 PM SATURDAY...
BASED ON THE LATEST QPF...AND CURRENT AND FORECAST RIVER LEVELS...
THE GREATEST POTENTIAL FOR MINOR FLOODING SHOULD BE ON THE NEUSE
RIVER AT SMITHFIELD. FLASH FLOOD GUIDANCE IS MOSTLY IN THE THREE-
INCH RANGE OR BETTER OVER SIX HOURS IN CENTRAL NORTH CAROLINA...SO
FOR THIS FORECAST PLAN TO REFRAIN FROM ANY FLOOD WATCHES. WILL
CONTINUE TO MENTION MAINSTEM RIVER RISES IN THE HWO...WITH A
POSSIBILITY OF MINOR FLOOD STAGES IN GENERAL...BUT IT APPEARS THE
PROBABILITY OF MINOR FLOOD STAGE BEING REACHED IS HIGHEST AT
SMITHFIELD.
&&
.CLIMATE...
FOR INFORMATIONAL PURPOSES...THE RECORD LOW MAXIMUM TEMPERATURES FOR
MARCH 17 ARE...
KGSO...38 DEGREES FROM 2005.
KRDU...32 DEGREES FROM 1892.
KFAY...39 DEGREES FROM 2005.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...NP/SMITH
SHORT TERM...DJF
LONG TERM...DJF
AVIATION...MWS
HYDROLOGY...DJF
CLIMATE...DJF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
118 PM CDT SUN MAR 16 2014
.UPDATE...
ISSUED AT 118 PM CDT SUN MAR 16 2014
KMBX CONTINUES TO INDICATE WEAK ECHOES MOVING EAST ACROSS NORTH
CENTRAL NORTH DAKOTA. STILL...NONE OF THE SURFACE OBS INDICATE ANY
PRECIPITATION REACHING THE GROUND. THE 12Z KBIS SOUNDING SHOWS A
VERY DRY LAYER BETWEEN 800MB-400MB. PRECIPITATION ALOFT IS LIKELY
EVAPORATING BEFORE IT REACHES THE SURFACE.
AS A RESULT...UPDATED FIRST PERIOD POPS TO SHIFT SLIGHT CHANCES
FOR PRECIPITATION FARTHER EAST EARLY THIS AFTERNOON.
OTHERWISE...MAINLY DRY CONDITIONS ARE EXPECTED THIS AFTERNOON AND
EARLY EVENING. THE UPDATED PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 943 AM CDT SUN MAR 16 2014
THE KMBX RADAR IS DETECTING LIGHT ECHOES OVER NORTHWESTERN AND
NORTH CENTRAL NORTH DAKOTA THIS MORNING. SURFACE OBS HAVE NOT
INDICATED ANY PRECIPITATION HITTING THE SURFACE YET. ALSO...THE
LATEST MODELS HOLD OFF ON PAINTING ANY QPF UNTIL LATER THIS
AFTERNOON. AS A RESULT...PULLED POPS FROM THIS MORNING`S FORECAST
AND DELAYED THEM OVER NORTH CENTRAL AND NORTHEASTERN NORTH DAKOTA
UNTIL THIS AFTERNOON.
THE PROBLEM OF THE DAY WILL BE DETERMINING THE TIMING AND LOCATION
OF FREEZING RAIN/SLEET DEVELOPING AFTER MIDNIGHT TONIGHT/EARLY
MONDAY MORNING. WILL CONTINUE TO ANALYZE THE 12Z MODELS AS THEY
COME IN TO MAKE A FINAL DECISION THIS AFTERNOON.
UPDATE ISSUED AT 647 AM CDT SUN MAR 16 2014
EARLY MORNING 11-3.9 MICRON SATELLITE IMAGERY SHOWS MID AND HIGH
CLOUDS MOVING OVER PATCHES OF STRATUS ACROSS WESTERN AND CENTRAL
NORTH DAKOTA. CLOUDS SHOULD CONTINUE TO INCREASE FROM WEST TO EAST
UNDER H85 WARM AIR ADVECTION. LIGHT PRECIPITATION IS POSSIBLE
TODAY WITH THE CONTINUED WARM AIR ADVECTION AND THE PASSING OF A
H5 WAVE. DELAYED THE START OF THE PRECIPITATION CHANCES BY A
COUPLE HOURS BASED ON THE LATEST RAP / HRRR. FORECAST SOUNDINGS
STILL SUPPORT A WINTRY MIX SO DID NOT ALTER PRECIPITATION TYPE AT
THIS POINT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CDT SUN MAR 16 2014
AT 3 AM CDT...A SURFACE LOW WAS OVER NORTHERN ALBERTA WITH A WARM
FRONT EXTENDING SOUTHWARD ALONG THE CANADIAN FRONT RANGE INTO THE
FRONT RANGE OF MONTANA AND WYOMING. MEANWHILE A COLD CANADIAN HIGH
PRESSURE CENTER WAS OVER THE MINNESOTA/ONTARIO BORDER.
SOUTH WINDS SHOULD CONTINUE TO INCREASE DURING THE DAY AS THE WARM
FRONT APPROACHES THE WESTERN DAKOTAS THIS MORNING. BY LATE
AFTERNOON/EARLY EVENING THE WARM FRONT IS PROGGED TO HAVE MOVED INTO
THE DEVILS LAKE AND JAMES RIVER BASINS. GOOD WARM ADVECTION AT H850
AS WELL AS AT THE SURFACE...WITH SOUTH WINDS BECOMING SOUTHWEST -
AND EVENTUALLY WEST - BEHIND THE FRONT. EXPECT TEMPERATURES IN THE
FAR WEST TO RISE INTO THE 50S TODAY...AND INTO THE MID TO UPPER 30S
FROM THE TURTLE MOUNTAINS TO THE JAMES RIVER BASIN.
AS THE WARM FRONT APPROACHES...THE MODELS ARE INDICATING AN UPPER
LEVEL ENERGY IMPULSE ON THE LEADING EDGE OF THE APPROACHING UPPER
LEVEL SHORTWAVE. THE GFS/EC MODELS AND THE 06Z NAM INDICATE LIGHT
PRECIPITATION AMOUNTS ACROSS NORTHERN TIER OF COUNTIES. ADDED A
SLIGHT CHANCE MENTION THIS MORNING NORTHWEST AND NORTH CENTRAL THIS
MORNING...AND KEPT THE SMALL CHANCES IN THE NORTH CENTRAL THIS
AFTERNOON. COULD BE LIGHT SNOW OR PERHAPS A MIX OF SNOW AND SLEET
BEFORE PRECIPITATION WOULD CHANGE TO RAIN.
TONIGHT THE MAIN UPPER LEVEL SHORTWAVE MOVES ACROSS THE ROCKIES AND
APPROACHES THE DAKOTAS. IN RESPONSE...SURFACE LOW PRESSURE IS
FORECAST TO DEVELOP OVER MONTANA. SOUTH/SOUTHWEST WINDS AHEAD OF THE
LOW SHOULD INSURE MILD TEMPERATURES OVERNIGHT. A BAROCLINIC ZONE
SETS UP MAINLY NORTH OF THE LOW FROM SOUTHERN ALBERTA/SASKATCHEWAN
SOUTHEASTWARD ACROSS NORTH DAKOTA TOWARDS SOUTHERN MINNESOTA. MOST
OF THIS PRECIPITATION WILL BE IN THE FORM OF RAIN...BUT OVER CENTRAL
NORTH DAKOTA WHERE OVERNIGHT LOWS MAY DIP BELOW FREEZING - THERE IS
A CHANCE OF SOME FREEZING RAIN AS WELL. CONFIDENCE IS AVERAGE TO A
BIT BELOW AVERAGE REGARDING THE AREAL COVERAGE AND LENGTH OF TIME OF
THE THREAT OF FREEZING RAIN.
THIS POTENTIAL HAZARD OF A MIX OF RAIN AND FREEZING RAIN TONIGHT
WILL REMAIN HIGHLIGHTED IN A SPECIAL WEATHER STATEMENT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 406 AM CDT SUN MAR 16 2014
THE MAIN CONCERN IN THE LONG TERM WILL SURROUND PRECIPITATION
CHANCES / AMOUNTS FOR MONDAY AND TUESDAY. THE 00Z MODELS STILL
HAVE DIFFERENCES REGARDING THE EVOLUTION OF THE PRECIPITATION
EVENT FOR MONDAY INTO TUESDAY LEADING TO BELOW AVERAGE CONFIDENCE.
THE 00Z GFS AND ECMWF HAVE SOME AGREEMENT INITIALLY IN THEIR
PLACEMENT OF THE SURFACE LOW MONDAY....BUT THEY DIVERGE TUESDAY
WITH THE GFS STRONGER AND FARTHER NORTH. FOR NOW WILL GO WITH A
00Z GFS / ECMWF BLEND WHICH IS IN LINE WITH WPC.
THE MIXED PRECIPITATION CHANCES FROM SUNDAY NIGHT WILL CONTINUE
INTO MONDAY MORNING...BUT AMOUNTS LOOK LIGHT. THE HIGHER
PRECIPITATION AMOUNTS SHOULD COME MONDAY NIGHT INTO TUESDAY AS THE
SURFACE LOW GATHERS STRENGTH ACROSS SOUTH DAKOTA. THERMAL PROFILES
SUGGEST A WINTRY MIX REMAINS POSSIBLE MONDAY NIGHT...BUT
EVERYTHING CHANGES TO SNOW FROM NORTHWEST TO SOUTHEAST AS COLDER
AIR ARRIVES.
IN REGARDS TO SNOW AMOUNTS...IT IS STILL TOO EARLY TO DISPLAY MUCH
CONFIDENCE...BUT IT DOES APPEAR THE SOUTHERN JAMES RIVER VALLEY
WOULD BE FAVORED FOR THE HIGHER AMOUNTS. THIS IS IN LINE WITH WPC
WWD TOTALS. AS MENTIONED ABOVE IN THE SHORT TERM SECTION...WILL
STICK WITH THE SPS AND HIGHLIGHT THE POTENTIAL FOR MIXED PRECIPITATION
AND ACCUMULATING SNOW MONDAY INTO TUESDAY.
ONCE THIS SYSTEM EXITS...THE REMAINDER OF THE LONG TERM PERIOD WILL
FEATURE THE PASSING OF PERIODIC WAVES THROUGH THE NORTHERN PLAINS.
PRECIPITATION AMOUNTS GENERALLY APPEAR LIGHT. HIGHS MUCH OF THE
WEEK SHOULD BE IN THE 30S / 40S...WITH LOWS AT NIGHT BELOW
FREEZING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 118 PM CDT SUN MAR 16 2014
VFR CONDITIONS/TEMPO MVFR CIGS WILL CONTINUE OVER PORTIONS OF
CENTRAL NORTH DAKOTA THIS AFTERNOON AND EVENING. LIGHT RAIN AND
ASSOCIATED MVFR CONDITIONS WILL DEVELOP FROM NORTHWEST TO
SOUTHEAST TONIGHT...WITH THE POTENTIAL FOR FREEZING RAIN OVER
KMOT-KJMS MAINLY BETWEEN 09Z-15Z MONDAY. KISN WILL LIKELY SEE ALL
RAIN WHEREAS KBIS COULD SEE A MIX. HOWEVER...CONFIDENCE IS LOW
THAT PRECIP WILL DEVELOP OVER KBIS DURING THE TAF PERIOD AT ALL
AND THEREFORE INDICATED THE POSSIBILITY WITH A VCSH. KDIK SHOULD
REMAIN VFR AND DRY THROUGH THE TAF PERIOD.
&&
.HYDROLOGY...
ISSUED AT 118 PM CDT SUN MAR 16 2014
NOTE...ICE IS AFFECTING MANY CREEKS AND RIVERS AND UNTIL THAT ICE
CLEARS...SIGNIFICANT FLUCTUATIONS IN WATER LEVELS ARE LIKELY.
FLOOD WARNINGS ARE IN EFFECT FOR THESE AREAS...IN THE MISSOURI
RIVER BASIN...
THE MISSOURI RIVER NEAR WILLISTON AFFECTING WILLIAMS AND MCKENZIE
COUNTIES. MODERATE FLOODING IS OCCURRING AND IS FORECAST TO CONTINUE
UNTIL THE RIVER NEAR WILLISTON BECOMES FREE OF ICE.
IN THE SOURIS RIVER BASIN...
SOURIS RIVER NEAR TOWNER AFFECTING MCHENRY COUNTY. MINOR FLOODING
IS FORECAST BY LATE TUESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...JV
LONG TERM...CK
AVIATION...TM
HYDROLOGY...TM/AJS
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
117 PM CDT SUN MAR 16 2014
.UPDATE...
ISSUED AT 117 PM CDT SUN MAR 16 2014
FORECAST ON TRACK FOR THE MOST PART. REGIONAL WSR-88DS NOW SHOWING
A NARROW BAND OF PRECIP FROM JUST WEST OF A LINE FROM BRANDON
MANITOBA TO RUGBY...MOVING TO THE EAST-SOUTHEAST AROUND 25 KTS.
THIS IS A BIT FASTER THAN WHAT WAS ADVERTISED FROM THE MORNING
UPDATE...SO ADJUSTED POPS TO MOVE PRECIP THROUGH THE FORECAST AREA
A BIT QUICKER THIS AFTERNOON AND EVENING. STILL NOT CERTAIN IF OR
WHAT IS REACHING THE GROUND SINCE THESE ECHOES HAVE JUST DEVELOPED
IN THE PAST HOUR AND HAVE NOT PASSED OVER ANY AUTOMATED STATIONS.
HIGHER CONFIDENCE NOW THAT MOST IF NOT ALL PRECIP WILL FALL AS
SNOW GIVEN THERMAL PROFILES...BUT STILL A SMALL PROBABILITY OF A
MIX ON THE BACK EDGE. WILL NOT MAKE ANY CHANGES TO SNOW/FREEZING
RAIN AMOUNTS AT THIS TIME. SOUTHERLY WINDS STILL EXPECTED TO PICK
UP THIS AFTERNOON WITH GUSTS UP TO 35 MPH...POSSIBLY RESULTING IN
SOME BLOWING AND DRIFTING SNOW.
UPDATE ISSUED AT 1010 AM CDT SUN MAR 16 2014
15 UTC WATER VAPOR LOOP SHOWS A SHORT-WAVE ROUNDING THE TOP OF THE
INTERMOUNTAIN WEST RIDGE ACROSS CENTRAL ALBERTA/SASKATCHEWAN AND
THIS PACKET OF ENERGY WILL DROP SOUTH AND EAST ACROSS SOUTHERN
CANADA AND THE NORTHERN PLAINS LATER THIS AFTERNOON AND EVENING.
WITH IT...STRONG MID-LEVEL WARM AIR ADVECTION WILL DEVELOP A
QUICK MOVING BAND OF PRECIP THAT WILL IMPACT MAINLY THE NORTHERN
HALF OF THE FORECAST AREA AFTER 21 UTC. INITIALLY...PRECIP WILL BE
ALL SNOW...BUT MAY TRANSITION INTO A FREEZING RAIN/SNOW MIX ON THE
TRAILING EDGE AS THE MAXIMUM TEMPERATURE ALOFT RISES ABOVE
FREEZING. FREEZING RAIN MAY BECOME MORE DOMINANT ACROSS PORTIONS
OF NORTHWEST MN AFTER 03 UTC AS MODEL SOUNDINGS SUGGEST DRYING IN
THE -10 TO -20 C LAYER. MAJORITY OF PRECIP WILL HAVE PUSHED EAST
BY THIS TIME...SO THINK ANY ICE ACCUMULATION WILL BE MINIMAL WITH
SNOW ACCUMULATIONS BETWEEN 0.5 AND 1.5 INCHES MAINLY NORTHEAST OF
A LINE FROM LANGDON TO THIEF RIVER FALLS TO WADENA. A FEW TENTHS
ARE POSSIBLE FARTHER SOUTH AND WEST.
OTHER CONCERN WILL BE INCREASING SOUTHERLY WINDS. RAP 925 HPA
WINDS INCREASE LATE THIS AFTERNOON AND EVENING WITH WIDESPREAD 35
TO 45 KTS ACROSS MOST OF THE FORECAST AREA BY 03 UTC. ADIABATIC
BOUNDARY LAYER DEEPENS TO AROUND 900 HPA BY 21 UTC...BUT
TRANSITIONS INTO AN INVERSION AFTER 00 UTC WITH INCREASING MID-
LEVEL TEMPERATURES. EXPECT BREEZY TO LOCALLY WINDY CONDITIONS THIS
AFTERNOON...BUT UNCERTAIN HOW MUCH OF THESE STRONGER WINDS AROUND
925 HPA WILL MIX TO THE SURFACE LATER THIS EVENING. DID ADD SOME
PATCHY BLOWING SNOW ACROSS THE NORTHERN VALLEY INTO PORTIONS OF
NORTHWEST MN WHERE THERE SHOULD BE AT LEAST SOME FALLING SNOW.
ALL THIS TO SAY...WILL NOT ISSUE ANY HEADLINES AT THIS TIME GIVEN
SOME UNCERTAINTY WITH PRECIP PHASE AND WINDS/BLOWING SNOW
POTENTIAL. HOWEVER...THERE COULD BE A FEW HOUR PERIOD LATE THIS
AFTERNOON AND EVENING WHERE CONDITIONS COULD BECOME HAZARDOUS...
ESPECIALLY ACROSS PORTIONS OF NORTHWEST MN FROM HALLOCK TO THIEF
RIVER FALLS TO BAUDETTE. WILL MONITOR AND MAKE ADJUSTMENTS AS
NECESSARY...BUT PERSONS WITH TRAVEL PLANS IN THIS AREA SHOULD KEEP
A CLOSE EYE ON THE LATEST ROAD AND WEATHER CONDITIONS.
UPDATE ISSUED AT 719 AM CDT SUN MAR 16 2014
DELAYED EASTWARD PROGRESSION OF CLOUDS THROUGH THE MORNING
OTHERWISE NO OTHER CHANGES MADE TO CURRENT FORECAST.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 330 AM CDT SUN MAR 16 2014
FORECAST CHALLENGE MAINLY CONCERNS STORM SYSTEM EARLY NEXT WEEK.
FOR THIS HAVE FOLLOWED GFS/ECMWF LOW TRACK SOLUTION WHICH IS A
COMPROMISE BETWEEN FARTHER NORTH NAM AND FARTHER SOUTH GEM
SOLUTIONS. FAIRLY WIDE SPREAD REMAINS IN QPF BETWEEN GFS AND
ECMWF FOR THE EVENT. EVENT NOT GETTING GOING TIL MONDAY NIGHT AND
AT THIS POINT CONFIDENCE LEVEL NOT WHERE I WANT TO BE TO ISSUE
ANY HEADLINES.
FOR TODAY SURFACE HIGH WILL SHIFT EAST SETTING UP INCREASING
RETURN FLOW AND WARM ADVECTION. BY AFTERNOON SHOULD SEE BREEZY/WINDY
CONDITIONS WHICH SHOULD ALLOW TEMPERATURES TO RECOVER CLOSE TO
SEASONAL AVERAGES. LATE THIS AFTERNOON AS UPPER LEVEL JET MAXIMA
APPROACHES MODELS CONTINUE TO INDICATE POTENTIAL FOR SOME PCPN TO
DEVELOP ACROSS THE NORTHERN FA ON NOSE OF UPPER JET.
BAND OF PCPN SHOULD PROPAGATE EASTWARD ACROSS THE NORTHERN FA THIS
EVENING SPREADING SOUTHWARD DURING THE OVERNIGHT. COULD SEE A MIX
AS WARMER AIR MOVES IN AND WILL NEED TO MONITOR BUT OVERALL BRUNT
OF PCPN SHOULD BE -SN. WILL SEE MUCH MILDER MINIMUMS TONIGHT AS
WARMER AIR PUSHES IN.
AS UPPER TROUGH CROSSES NORTHERN ROCKIES MONDAY WILL SEE
ORGANIZING LOW PRESSURE ACROSS THE NORTHERN HIGH PLAINS. MODELS
DIFFER ON WHERE AND HOW MUCH PCPN WILL DEVELOP DURING THE DAY AND
WILL BE DEPENDENT ON WHERE LOW LEVEL BOUNDARY SETS UP. PHASE WILL
BE A CHALLENGE AND COULD SEE A MIX DEVELOP DURING THE COURSE OF
THE DAY WHICH WILL NEED TO BE MONITORED.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 AM CDT SUN MAR 16 2014
SURFACE LOW DEEPENS MONDAY NIGHT INTO TUESDAY AS IT PROPAGATES
ESE ACROSS THE CENTRAL PLAINS. ECMWF/GEM KEEP MID LEVEL WAVE OPEN
AT THIS POINT WHERE THE GFS AND NAM CLOSE IT OFF. THIS HAS MAIN
IMPACT ON QPF POTENTIAL AND DEPTH OF SURFACE LOW. SNOW WILL TAPER
DOWN TUESDAY NIGHT AS LOW EXITS TO THE EAST.
WITH MAIN IMPACTS IN PERIODS 4-5 AND ALL OF THE ABOVE
UNCERTAINTIES DID NOT ISSUE ANY HEADLINES BUT WILL POST POTENTIAL IN
SPS/HWO AND WX STORY.
WEDNESDAY TO SATURDAY...ACTIVE STORM TRACK TO REMAIN SOUTH OF THE
FORECAST AREA WITH ZONAL TO NW 500MB FLOW FOR THE LATTER HALF OF THE
WEEK. ONLY SHORT WAVE EXPECTED TO IMPACT THE AREA IS TIMED FOR
THURSDAY WITH CHC FOR -SN. OTHERWISE MID MARCH NORMALS FORECASTED
WITH MAX TEMPS IN THE 30S TO LOW 40S AND MINS IN THE 10 TO 20 DEGREE
RANGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 117 PM CDT SUN MAR 16 2014
SOUTHERLY WINDS WILL GUST TO NEAR 30KT THIS AFTERNOON INTO THE EARLY
EVENING. A BAND OF LIGHT SNOW MAY BRUSH THE FAR NORTH THIS EVENING.
MODELS INDICATE THE THREAT OF IFR CIGS AND/OR BR LATER TONIGHT INTO
TUE. HAVE STARTED THIS TREND WITH LOWERING CIGS/VSBYS INTO MVFR
RANGE MAINLY IN THE NORTH AND EAST LATER TONIGHT AS WINDS SHIFT MORE
WESTERLY AND DECREASE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...ROGERS
SHORT TERM...VOELKER
LONG TERM...JK/VOELKER
AVIATION...DK
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1010 AM CDT SUN MAR 16 2014
.UPDATE...
ISSUED AT 1010 AM CDT SUN MAR 16 2014
15 UTC WATER VAPOR LOOP SHOWS A SHORT-WAVE ROUNDING THE TOP OF THE
INTERMOUNTAIN WEST RIDGE ACROSS CENTRAL ALBERTA/SASKATCHEWAN AND
THIS PACKET OF ENERGY WILL DROP SOUTH AND EAST ACROSS SOUTHERN
CANADA AND THE NORTHERN PLAINS LATER THIS AFTERNOON AND EVENING.
WITH IT...STRONG MID-LEVEL WARM AIR ADVECTION WILL DEVELOP A
QUICK MOVING BAND OF PRECIP THAT WILL IMPACT MAINLY THE NORTHERN
HALF OF THE FORECAST AREA AFTER 21 UTC. INITIALLY...PRECIP WILL BE
ALL SNOW...BUT MAY TRANSITION INTO A FREEZING RAIN/SNOW MIX ON THE
TRAILING EDGE AS THE MAXIMUM TEMPERATURE ALOFT RISES ABOVE
FREEZING. FREEZING RAIN MAY BECOME MORE DOMINANT ACROSS PORTIONS
OF NORTHWEST MN AFTER 03 UTC AS MODEL SOUNDINGS SUGGEST DRYING IN
THE -10 TO -20 C LAYER. MAJORITY OF PRECIP WILL HAVE PUSHED EAST
BY THIS TIME...SO THINK ANY ICE ACCUMULATION WILL BE MINIMAL WITH
SNOW ACCUMULATIONS BETWEEN 0.5 AND 1.5 INCHES MAINLY NORTHEAST OF
A LINE FROM LANGDON TO THIEF RIVER FALLS TO WADENA. A FEW TENTHS
ARE POSSIBLE FARTHER SOUTH AND WEST.
OTHER CONCERN WILL BE INCREASING SOUTHERLY WINDS. RAP 925 HPA
WINDS INCREASE LATE THIS AFTERNOON AND EVENING WITH WIDESPREAD 35
TO 45 KTS ACROSS MOST OF THE FORECAST AREA BY 03 UTC. ADIABATIC
BOUNDARY LAYER DEEPENS TO AROUND 900 HPA BY 21 UTC...BUT
TRANSITIONS INTO AN INVERSION AFTER 00 UTC WITH INCREASING MID-
LEVEL TEMPERATURES. EXPECT BREEZY TO LOCALLY WINDY CONDITIONS THIS
AFTERNOON...BUT UNCERTAIN HOW MUCH OF THESE STRONGER WINDS AROUND
925 HPA WILL MIX TO THE SURFACE LATER THIS EVENING. DID ADD SOME
PATCHY BLOWING SNOW ACROSS THE NORTHERN VALLEY INTO PORTIONS OF
NORTHWEST MN WHERE THERE SHOULD BE AT LEAST SOME FALLING SNOW.
ALL THIS TO SAY...WILL NOT ISSUE ANY HEADLINES AT THIS TIME GIVEN
SOME UNCERTAINTY WITH PRECIP PHASE AND WINDS/BLOWING SNOW
POTENTIAL. HOWEVER...THERE COULD BE A FEW HOUR PERIOD LATE THIS
AFTERNOON AND EVENING WHERE CONDITIONS COULD BECOME HAZARDOUS...
ESPECIALLY ACROSS PORTIONS OF NORTHWEST MN FROM HALLOCK TO THIEF
RIVER FALLS TO BAUDETTE. WILL MONITOR AND MAKE ADJUSTMENTS AS
NECESSARY...BUT PERSONS WITH TRAVEL PLANS IN THIS AREA SHOULD KEEP
A CLOSE EYE ON THE LATEST ROAD AND WEATHER CONDITIONS.
UPDATE ISSUED AT 719 AM CDT SUN MAR 16 2014
DELAYED EASTWARD PROGRESSION OF CLOUDS THROUGH THE MORNING
OTHERWISE NO OTHER CHANGES MADE TO CURRENT FORECAST.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 330 AM CDT SUN MAR 16 2014
FORECAST CHALLENGE MAINLY CONCERNS STORM SYSTEM EARLY NEXT WEEK.
FOR THIS HAVE FOLLOWED GFS/ECMWF LOW TRACK SOLUTION WHICH IS A
COMPROMISE BETWEEN FARTHER NORTH NAM AND FARTHER SOUTH GEM
SOLUTIONS. FAIRLY WIDE SPREAD REMAINS IN QPF BETWEEN GFS AND
ECMWF FOR THE EVENT. EVENT NOT GETTING GOING TIL MONDAY NIGHT AND
AT THIS POINT CONFIDENCE LEVEL NOT WHERE I WANT TO BE TO ISSUE
ANY HEADLINES.
FOR TODAY SURFACE HIGH WILL SHIFT EAST SETTING UP INCREASING
RETURN FLOW AND WARM ADVECTION. BY AFTERNOON SHOULD SEE BREEZY/WINDY
CONDITIONS WHICH SHOULD ALLOW TEMPERATURES TO RECOVER CLOSE TO
SEASONAL AVERAGES. LATE THIS AFTERNOON AS UPPER LEVEL JET MAXIMA
APPROACHES MODELS CONTINUE TO INDICATE POTENTIAL FOR SOME PCPN TO
DEVELOP ACROSS THE NORTHERN FA ON NOSE OF UPPER JET.
BAND OF PCPN SHOULD PROPAGATE EASTWARD ACROSS THE NORTHERN FA THIS
EVENING SPREADING SOUTHWARD DURING THE OVERNIGHT. COULD SEE A MIX
AS WARMER AIR MOVES IN AND WILL NEED TO MONITOR BUT OVERALL BRUNT
OF PCPN SHOULD BE -SN. WILL SEE MUCH MILDER MINIMUMS TONIGHT AS
WARMER AIR PUSHES IN.
AS UPPER TROUGH CROSSES NORTHERN ROCKIES MONDAY WILL SEE
ORGANIZING LOW PRESSURE ACROSS THE NORTHERN HIGH PLAINS. MODELS
DIFFER ON WHERE AND HOW MUCH PCPN WILL DEVELOP DURING THE DAY AND
WILL BE DEPENDENT ON WHERE LOW LEVEL BOUNDARY SETS UP. PHASE WILL
BE A CHALLENGE AND COULD SEE A MIX DEVELOP DURING THE COURSE OF
THE DAY WHICH WILL NEED TO BE MONITORED.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 330 AM CDT SUN MAR 16 2014
SURFACE LOW DEEPENS MONDAY NIGHT INTO TUESDAY AS IT PROPAGATES
ESE ACROSS THE CENTRAL PLAINS. ECMWF/GEM KEEP MID LEVEL WAVE OPEN
AT THIS POINT WHERE THE GFS AND NAM CLOSE IT OFF. THIS HAS MAIN
IMPACT ON QPF POTENTIAL AND DEPTH OF SURFACE LOW. SNOW WILL TAPER
DOWN TUESDAY NIGHT AS LOW EXITS TO THE EAST.
WITH MAIN IMPACTS IN PERIODS 4-5 AND ALL OF THE ABOVE
UNCERTAINTIES DID NOT ISSUE ANY HEADLINES BUT WILL POST POTENTIAL IN
SPS/HWO AND WX STORY.
WEDNESDAY TO SATURDAY...ACTIVE STORM TRACK TO REMAIN SOUTH OF THE
FORECAST AREA WITH ZONAL TO NW 500MB FLOW FOR THE LATTER HALF OF THE
WEEK. ONLY SHORT WAVE EXPECTED TO IMPACT THE AREA IS TIMED FOR
THURSDAY WITH CHC FOR -SN. OTHERWISE MID MARCH NORMALS FORECASTED
WITH MAX TEMPS IN THE 30S TO LOW 40S AND MINS IN THE 10 TO 20 DEGREE
RANGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 719 AM CDT SUN MAR 16 2014
WILL SEE INCREASING SOUTH WINDS AND CLOUDS THROUGH THE DAY. THERE
IS A THINNING BAND OF MVFR CIGS APPROACHING THE DVL REGION HOWEVER
NOT SURE HOW THIS WILL HOLD TOGETHER. REMAINDER OF THE FA SHOULD
REMAIN VFR THROUGH THE DAY. SOME PCPN MAY DEVELOP ACROSS THE FAR
NORTH LATE THIS AFTERNOON SPREADING EAST AND SOUTH DURING THE
OVERNIGHT. INITIALLY COULD SEE SOME MIXED PCPN HOWEVER MOST OF THE
PCPN SHOULD BE IN THE FORM OF -SN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...ROGERS
SHORT TERM...VOELKER
LONG TERM...JK/VOELKER
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
943 AM CDT SUN MAR 16 2014
.UPDATE...
ISSUED AT 943 AM CDT SUN MAR 16 2014
THE KMBX RADAR IS DETECTING LIGHT ECHOES OVER NORTHWESTERN AND
NORTH CENTRAL NORTH DAKOTA THIS MORNING. SURFACE OBS HAVE NOT
INDICATED ANY PRECIPITATION HITTING THE SURFACE YET. ALSO...THE
LATEST MODELS HOLD OFF ON PAINTING ANY QPF UNTIL LATER THIS
AFTERNOON. AS A RESULT...PULLED POPS FROM THIS MORNING`S FORECAST
AND DELAYED THEM OVER NORTH CENTRAL AND NORTHEASTERN NORTH DAKOTA
UNTIL THIS AFTERNOON.
THE PROBLEM OF THE DAY WILL BE DETERMINING THE TIMING AND LOCATION
OF FREEZING RAIN/SLEET DEVELOPING AFTER MIDNIGHT TONIGHT/EARLY
MONDAY MORNING. WILL CONTINUE TO ANALYZE THE 12Z MODELS AS THEY
COME IN TO MAKE A FINAL DECISION THIS AFTERNOON.
UPDATE ISSUED AT 647 AM CDT SUN MAR 16 2014
EARLY MORNING 11-3.9 MICRON SATELLITE IMAGERY SHOWS MID AND HIGH
CLOUDS MOVING OVER PATCHES OF STRATUS ACROSS WESTERN AND CENTRAL
NORTH DAKOTA. CLOUDS SHOULD CONTINUE TO INCREASE FROM WEST TO EAST
UNDER H85 WARM AIR ADVECTION. LIGHT PRECIPITATION IS POSSIBLE
TODAY WITH THE CONTINUED WARM AIR ADVECTION AND THE PASSING OF A
H5 WAVE. DELAYED THE START OF THE PRECIPITATION CHANCES BY A
COUPLE HOURS BASED ON THE LATEST RAP / HRRR. FORECAST SOUNDINGS
STILL SUPPORT A WINTRY MIX SO DID NOT ALTER PRECIPITATION TYPE AT
THIS POINT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CDT SUN MAR 16 2014
AT 3 AM CDT...A SURFACE LOW WAS OVER NORTHERN ALBERTA WITH A WARM
FRONT EXTENDING SOUTHWARD ALONG THE CANADIAN FRONT RANGE INTO THE
FRONT RANGE OF MONTANA AND WYOMING. MEANWHILE A COLD CANADIAN HIGH
PRESSURE CENTER WAS OVER THE MINNESOTA/ONTARIO BORDER.
SOUTH WINDS SHOULD CONTINUE TO INCREASE DURING THE DAY AS THE WARM
FRONT APPROACHES THE WESTERN DAKOTAS THIS MORNING. BY LATE
AFTERNOON/EARLY EVENING THE WARM FRONT IS PROGGED TO HAVE MOVED INTO
THE DEVILS LAKE AND JAMES RIVER BASINS. GOOD WARM ADVECTION AT H850
AS WELL AS AT THE SURFACE...WITH SOUTH WINDS BECOMING SOUTHWEST -
AND EVENTUALLY WEST - BEHIND THE FRONT. EXPECT TEMPERATURES IN THE
FAR WEST TO RISE INTO THE 50S TODAY...AND INTO THE MID TO UPPER 30S
FROM THE TURTLE MOUNTAINS TO THE JAMES RIVER BASIN.
AS THE WARM FRONT APPROACHES...THE MODELS ARE INDICATING AN UPPER
LEVEL ENERGY IMPULSE ON THE LEADING EDGE OF THE APPROACHING UPPER
LEVEL SHORTWAVE. THE GFS/EC MODELS AND THE 06Z NAM INDICATE LIGHT
PRECIPITATION AMOUNTS ACROSS NORTHERN TIER OF COUNTIES. ADDED A
SLIGHT CHANCE MENTION THIS MORNING NORTHWEST AND NORTH CENTRAL THIS
MORNING...AND KEPT THE SMALL CHANCES IN THE NORTH CENTRAL THIS
AFTERNOON. COULD BE LIGHT SNOW OR PERHAPS A MIX OF SNOW AND SLEET
BEFORE PRECIPITATION WOULD CHANGE TO RAIN.
TONIGHT THE MAIN UPPER LEVEL SHORTWAVE MOVES ACROSS THE ROCKIES AND
APPROACHES THE DAKOTAS. IN RESPONSE...SURFACE LOW PRESSURE IS
FORECAST TO DEVELOP OVER MONTANA. SOUTH/SOUTHWEST WINDS AHEAD OF THE
LOW SHOULD INSURE MILD TEMPERATURES OVERNIGHT. A BAROCLINIC ZONE
SETS UP MAINLY NORTH OF THE LOW FROM SOUTHERN ALBERTA/SASKATCHEWAN
SOUTHEASTWARD ACROSS NORTH DAKOTA TOWARDS SOUTHERN MINNESOTA. MOST
OF THIS PRECIPITATION WILL BE IN THE FORM OF RAIN...BUT OVER CENTRAL
NORTH DAKOTA WHERE OVERNIGHT LOWS MAY DIP BELOW FREEZING - THERE IS
A CHANCE OF SOME FREEZING RAIN AS WELL. CONFIDENCE IS AVERAGE TO A
BIT BELOW AVERAGE REGARDING THE AREAL COVERAGE AND LENGTH OF TIME OF
THE THREAT OF FREEZING RAIN.
THIS POTENTIAL HAZARD OF A MIX OF RAIN AND FREEZING RAIN TONIGHT
WILL REMAIN HIGHLIGHTED IN A SPECIAL WEATHER STATEMENT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 406 AM CDT SUN MAR 16 2014
THE MAIN CONCERN IN THE LONG TERM WILL SURROUND PRECIPITATION
CHANCES / AMOUNTS FOR MONDAY AND TUESDAY. THE 00Z MODELS STILL
HAVE DIFFERENCES REGARDING THE EVOLUTION OF THE PRECIPITATION
EVENT FOR MONDAY INTO TUESDAY LEADING TO BELOW AVERAGE CONFIDENCE.
THE 00Z GFS AND ECMWF HAVE SOME AGREEMENT INITIALLY IN THEIR
PLACEMENT OF THE SURFACE LOW MONDAY....BUT THEY DIVERGE TUESDAY
WITH THE GFS STRONGER AND FARTHER NORTH. FOR NOW WILL GO WITH A
00Z GFS / ECMWF BLEND WHICH IS IN LINE WITH WPC.
THE MIXED PRECIPITATION CHANCES FROM SUNDAY NIGHT WILL CONTINUE
INTO MONDAY MORNING...BUT AMOUNTS LOOK LIGHT. THE HIGHER
PRECIPITATION AMOUNTS SHOULD COME MONDAY NIGHT INTO TUESDAY AS THE
SURFACE LOW GATHERS STRENGTH ACROSS SOUTH DAKOTA. THERMAL PROFILES
SUGGEST A WINTRY MIX REMAINS POSSIBLE MONDAY NIGHT...BUT
EVERYTHING CHANGES TO SNOW FROM NORTHWEST TO SOUTHEAST AS COLDER
AIR ARRIVES.
IN REGARDS TO SNOW AMOUNTS...IT IS STILL TOO EARLY TO DISPLAY MUCH
CONFIDENCE...BUT IT DOES APPEAR THE SOUTHERN JAMES RIVER VALLEY
WOULD BE FAVORED FOR THE HIGHER AMOUNTS. THIS IS IN LINE WITH WPC
WWD TOTALS. AS MENTIONED ABOVE IN THE SHORT TERM SECTION...WILL
STICK WITH THE SPS AND HIGHLIGHT THE POTENTIAL FOR MIXED PRECIPITATION
AND ACCUMULATING SNOW MONDAY INTO TUESDAY.
ONCE THIS SYSTEM EXITS...THE REMAINDER OF THE LONG TERM PERIOD WILL
FEATURE THE PASSING OF PERIODIC WAVES THROUGH THE NORTHERN PLAINS.
PRECIPITATION AMOUNTS GENERALLY APPEAR LIGHT. HIGHS MUCH OF THE
WEEK SHOULD BE IN THE 30S / 40S...WITH LOWS AT NIGHT BELOW
FREEZING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 647 AM CDT SUN MAR 16 2014
WARM FRONT ACROSS CENTRAL MONTANA WILL MOVE EAST INTO THE DAKOTAS
TODAY. AN IFR STRATUS DECK WAS MOVING NORTHWARD FROM SOUTH DAKOTA
AND WILL AFFECT KDIK/KISN THIS MORNING BEFORE SCATTERING OUT AFT
15Z. THE MVFR/VFR STRATUS DECK OF 3000-4000 FEET ACROSS CENTRAL
NORTH DAKOTA FROM KBIS-KMOT SLOWLY ERODE THROUGH 18Z. SOUTH WINDS
TO INCREASE TO OR REMAIN AT 17-20 KNOTS AT KMOT-KBIS-KJMS THROUGH
21Z...THEN BECOME SOUTHWESTERLY LATE AFTERNOON. RAIN LIKELY
KISN/KMOT AFT 06Z.
&&
.HYDROLOGY...
ISSUED AT 647 AM CDT SUN MAR 16 2014
NOTE THAT ICE WAS AFFECTING CREEKS AND RIVERS AND UNTIL THAT ICE
CLEARS...SIGNIFICANT FLUCTUATIONS IN WATER LEVELS ARE LIKELY.
EVEN THOUGH THE BEAVER CREEK AT LINTON IS AT 12.5 FEET...WHICH IS
MODERATE FLOOD STAGE...LOCAL EMERGENCY MANAGEMENT ASSURED US THAT
THERE ARE NO IMPACTS AT THIS STAGE. THEY ARE CURRENTLY DOCUMENTING
THE LACK OF IMPACTS AT THIS STAGE AND AT MAJOR FLOOD STAGE OF 13
FEET IN AN EFFORT TO RE-ASSESS THE FLOOD CATEGORIES AT A LATER
DATE. AS A RESULT OF COORDINATING WITH LOCAL EMERGENCY
MANAGEMENT...THE NWS WILL HOLD OFF ON ISSUING A RIVER FLOOD
WARNING FOR THE BEAVER CREEK.
OTHERWISE...FLOOD WARNINGS ARE IN EFFECT FOR THESE AREAS...IN THE
MISSOURI RIVER BASIN...
THE MISSOURI RIVER NEAR WILLISTON AFFECTING WILLIAMS AND MCKENZIE
COUNTIES. MODERATE TO MAJOR FLOODING IS OCCURRING AND IS FORECAST TO
CONTINUE.
LITTLE MISSOURI RIVER AT MEDORA AFFECTING BILLINGS AND GOLDEN
VALLEY COUNTIES. MINOR FLOODING IS FORECAST DUE TO ICE JAMS.
CANNONBALL RIVER AT BREIEN AFFECTING MORTON AND SIOUX COUNTIES.
THE RIVER HAS FALLEN BELOW FLOOD STAGE AT BREIEN...BUT DID NOT
CLEAR THE WARNING YET TO ALLOW MORE TIME FOR ADDITIONAL AREAS
WITHIN THE WARNING POLYGON TO ALSO FALL BELOW FLOOD STAGE.
IN SOUTHWEST NORTH DAKOTA...THE LITTLE MISSOURI THROUGH BOWMAN
AND SLOPE COUNTIES. ICE JAM FLOODING CAUSING RAPID FLUCTUATIONS IN
WATER LEVELS SHOULD BE NEARING AN END.
IN THE SOURIS RIVER BASIN...
A FLOOD WARNING HAS BEEN ISSUED FOR THE SOURIS RIVER NEAR TOWNER
AFFECTING MCHENRY COUNTY. MINOR FLOODING IS FORECAST BY LATE
TUESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...JV
LONG TERM...CK
AVIATION...JV
HYDROLOGY...TM/AJS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
648 AM CDT SUN MAR 16 2014
.UPDATE...
ISSUED AT 647 AM CDT SUN MAR 16 2014
EARLY MORNING 11-3.9 MICRON SATELLITE IMAGERY SHOWS MID AND HIGH
CLOUDS MOVING OVER PATCHES OF STRATUS ACROSS WESTERN AND CENTRAL
NORTH DAKOTA. CLOUDS SHOULD CONTINUE TO INCREASE FROM WEST TO EAST
UNDER H85 WARM AIR ADVECTION. LIGHT PRECIPITATION IS POSSIBLE
TODAY WITH THE CONTINUED WARM AIR ADVECTION AND THE PASSING OF A
H5 WAVE. DELAYED THE START OF THE PRECIPITATION CHANCES BY A
COUPLE HOURS BASED ON THE LATEST RAP / HRRR. FORECAST SOUNDINGS
STILL SUPPORT A WINTRY MIX SO DID NOT ALTER PRECIPITATION TYPE AT
THIS POINT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM CDT SUN MAR 16 2014
AT 3 AM CDT...A SURFACE LOW WAS OVER NORTHERN ALBERTA WITH A WARM
FRONT EXTENDING SOUTHWARD ALONG THE CANADIAN FRONT RANGE INTO THE
FRONT RANGE OF MONTANA AND WYOMING. MEANWHILE A COLD CANADIAN HIGH
PRESSURE CENTER WAS OVER THE MINNESOTA/ONTARIO BORDER.
SOUTH WINDS SHOULD CONTINUE TO INCREASE DURING THE DAY AS THE WARM
FRONT APPROACHES THE WESTERN DAKOTAS THIS MORNING. BY LATE
AFTERNOON/EARLY EVENING THE WARM FRONT IS PROGGED TO HAVE MOVED INTO
THE DEVILS LAKE AND JAMES RIVER BASINS. GOOD WARM ADVECTION AT H850
AS WELL AS AT THE SURFACE...WITH SOUTH WINDS BECOMING SOUTHWEST -
AND EVENTUALLY WEST - BEHIND THE FRONT. EXPECT TEMPERATURES IN THE
FAR WEST TO RISE INTO THE 50S TODAY...AND INTO THE MID TO UPPER 30S
FROM THE TURTLE MOUNTAINS TO THE JAMES RIVER BASIN.
AS THE WARM FRONT APPROACHES...THE MODELS ARE INDICATING AN UPPER
LEVEL ENERGY IMPULSE ON THE LEADING EDGE OF THE APPROACHING UPPER
LEVEL SHORTWAVE. THE GFS/EC MODELS AND THE 06Z NAM INDICATE LIGHT
PRECIPITATION AMOUNTS ACROSS NORTHERN TIER OF COUNTIES. ADDED A
SLIGHT CHANCE MENTION THIS MORNING NORTHWEST AND NORTH CENTRAL THIS
MORNING...AND KEPT THE SMALL CHANCES IN THE NORTH CENTRAL THIS
AFTERNOON. COULD BE LIGHT SNOW OR PERHAPS A MIX OF SNOW AND SLEET
BEFORE PRECIPITATION WOULD CHANGE TO RAIN.
TONIGHT THE MAIN UPPER LEVEL SHORTWAVE MOVES ACROSS THE ROCKIES AND
APPROACHES THE DAKOTAS. IN RESPONSE...SURFACE LOW PRESSURE IS
FORECAST TO DEVELOP OVER MONTANA. SOUTH/SOUTHWEST WINDS AHEAD OF THE
LOW SHOULD INSURE MILD TEMPERATURES OVERNIGHT. A BAROCLINIC ZONE
SETS UP MAINLY NORTH OF THE LOW FROM SOUTHERN ALBERTA/SASKATCHEWAN
SOUTHEASTWARD ACROSS NORTH DAKOTA TOWARDS SOUTHERN MINNESOTA. MOST
OF THIS PRECIPITATION WILL BE IN THE FORM OF RAIN...BUT OVER CENTRAL
NORTH DAKOTA WHERE OVERNIGHT LOWS MAY DIP BELOW FREEZING - THERE IS
A CHANCE OF SOME FREEZING RAIN AS WELL. CONFIDENCE IS AVERAGE TO A
BIT BELOW AVERAGE REGARDING THE AREAL COVERAGE AND LENGTH OF TIME OF
THE THREAT OF FREEZING RAIN.
THIS POTENTIAL HAZARD OF A MIX OF RAIN AND FREEZING RAIN TONIGHT
WILL REMAIN HIGHLIGHTED IN A SPECIAL WEATHER STATEMENT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 406 AM CDT SUN MAR 16 2014
THE MAIN CONCERN IN THE LONG TERM WILL SURROUND PRECIPITATION
CHANCES / AMOUNTS FOR MONDAY AND TUESDAY. THE 00Z MODELS STILL
HAVE DIFFERENCES REGARDING THE EVOLUTION OF THE PRECIPITATION
EVENT FOR MONDAY INTO TUESDAY LEADING TO BELOW AVERAGE CONFIDENCE.
THE 00Z GFS AND ECMWF HAVE SOME AGREEMENT INITIALLY IN THEIR
PLACEMENT OF THE SURFACE LOW MONDAY....BUT THEY DIVERGE TUESDAY
WITH THE GFS STRONGER AND FARTHER NORTH. FOR NOW WILL GO WITH A
00Z GFS / ECMWF BLEND WHICH IS IN LINE WITH WPC.
THE MIXED PRECIPITATION CHANCES FROM SUNDAY NIGHT WILL CONTINUE
INTO MONDAY MORNING...BUT AMOUNTS LOOK LIGHT. THE HIGHER
PRECIPITATION AMOUNTS SHOULD COME MONDAY NIGHT INTO TUESDAY AS THE
SURFACE LOW GATHERS STRENGTH ACROSS SOUTH DAKOTA. THERMAL PROFILES
SUGGEST A WINTRY MIX REMAINS POSSIBLE MONDAY NIGHT...BUT
EVERYTHING CHANGES TO SNOW FROM NORTHWEST TO SOUTHEAST AS COLDER
AIR ARRIVES.
IN REGARDS TO SNOW AMOUNTS...IT IS STILL TOO EARLY TO DISPLAY MUCH
CONFIDENCE...BUT IT DOES APPEAR THE SOUTHERN JAMES RIVER VALLEY
WOULD BE FAVORED FOR THE HIGHER AMOUNTS. THIS IS IN LINE WITH WPC
WWD TOTALS. AS MENTIONED ABOVE IN THE SHORT TERM SECTION...WILL
STICK WITH THE SPS AND HIGHLIGHT THE POTENTIAL FOR MIXED PRECIPITATION
AND ACCUMULATING SNOW MONDAY INTO TUESDAY.
ONCE THIS SYSTEM EXITS...THE REMAINDER OF THE LONG TERM PERIOD WILL
FEATURE THE PASSING OF PERIODIC WAVES THROUGH THE NORTHERN PLAINS.
PRECIPITATION AMOUNTS GENERALLY APPEAR LIGHT. HIGHS MUCH OF THE
WEEK SHOULD BE IN THE 30S / 40S...WITH LOWS AT NIGHT BELOW
FREEZING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 647 AM CDT SUN MAR 16 2014
WARM FRONT ACROSS CENTRAL MONTANA WILL MOVE EAST INTO THE DAKOTAS
TODAY. AN IFR STRATUS DECK WAS MOVING NORTHWARD FROM SOUTH DAKOTA
AND WILL AFFECT KDIK/KISN THIS MORNING BEFORE SCATTERING OUT AFT
15Z. THE MVFR/VFR STRATUS DECK OF 3000-4000 FEET ACROSS CENTRAL
NORTH DAKOTA FROM KBIS-KMOT SLOWLY ERODE THROUGH 18Z. SOUTH WINDS
TO INCREASE TO OR REMAIN AT 17-20 KNOTS AT KMOT-KBIS-KJMS THROUGH
21Z...THEN BECOME SOUTHWESTERLY LATE AFTERNOON. RAIN LIKELY
KISN/KMOT AFT 06Z.
&&
.HYDROLOGY...
ISSUED AT 647 AM CDT SUN MAR 16 2014
NOTE THAT ICE WAS AFFECTING CREEKS AND RIVERS AND UNTIL THAT ICE
CLEARS...SIGNIFICANT FLUCTUATIONS IN WATER LEVELS ARE LIKELY.
EVEN THOUGH THE BEAVER CREEK AT LINTON IS AT 12.5 FEET...WHICH IS
MODERATE FLOOD STAGE...LOCAL EMERGENCY MANAGEMENT ASSURED US THAT
THERE ARE NO IMPACTS AT THIS STAGE. THEY ARE CURRENTLY DOCUMENTING
THE LACK OF IMPACTS AT THIS STAGE AND AT MAJOR FLOOD STAGE OF 13
FEET IN AN EFFORT TO RE-ASSESS THE FLOOD CATEGORIES AT A LATER
DATE. AS A RESULT OF COORDINATING WITH LOCAL EMERGENCY
MANAGEMENT...THE NWS WILL HOLD OFF ON ISSUING A RIVER FLOOD
WARNING FOR THE BEAVER CREEK.
OTHERWISE...FLOOD WARNINGS ARE IN EFFECT FOR THESE AREAS...IN THE
MISSOURI RIVER BASIN...
THE MISSOURI RIVER NEAR WILLISTON AFFECTING WILLIAMS AND MCKENZIE
COUNTIES. MODERATE TO MAJOR FLOODING IS OCCURRING AND IS FORECAST TO
CONTINUE.
LITTLE MISSOURI RIVER AT MEDORA AFFECTING BILLINGS AND GOLDEN
VALLEY COUNTIES. MINOR FLOODING IS FORECAST DUE TO ICE JAMS.
CANNONBALL RIVER AT BREIEN AFFECTING MORTON AND SIOUX COUNTIES.
THE RIVER HAS FALLEN BELOW FLOOD STAGE AT BREIEN...BUT DID NOT
CLEAR THE WARNING YET TO ALLOW MORE TIME FOR ADDITIONAL AREAS
WITHIN THE WARNING POLYGON TO ALSO FALL BELOW FLOOD STAGE.
IN SOUTHWEST NORTH DAKOTA...THE LITTLE MISSOURI THROUGH BOWMAN
AND SLOPE COUNTIES. ICE JAM FLOODING CAUSING RAPID FLUCTUATIONS IN
WATER LEVELS SHOULD BE NEARING AN END.
IN THE SOURIS RIVER BASIN...
A FLOOD WARNING HAS BEEN ISSUED FOR THE SOURIS RIVER NEAR TOWNER
AFFECTING MCHENRY COUNTY. MINOR FLOODING IS FORECAST BY LATE
TUESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...JV
LONG TERM...CK
AVIATION...JV
HYDROLOGY...TM/AJS
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
657 AM EDT SUN MAR 16 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY MOVE ACROSS THE GREAT LAKES THROUGH THE
EARLY PART OF THE WEEK. A TROUGH OF LOW PRESSURE WILL DEVELOP
OVER KENTUCKY TODAY AND MOVE OFF TO THE EAST AND WEAKEN BY MONDAY.
A COLD FRONT WILL PUSH INTO THE REGION ON WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
FORECAST AREA WILL BE BETWEEN HIGH PRESSURE MOVING INTO THE GREAT
LAKES AND A LOW TRACKING ACROSS THE GULF COAST STATES. AN INVERTED
TROUGH EXTENDING FROM THE LOW WILL PUSH INTO KENTUCKY TODAY AND
HEAD TOWARDS THE WESTERN SLOPES OF THE APPALACHIANS TONIGHT. A
SHORT WAVE OVER THE SOUTHERN PLAINS WILL GET SHEARED OUT AS IT
MOVES EAST INTO CONFLUENT UPPER LEVEL FLOW THIS AFTERNOON AND
TONIGHT.
PRECIPITATION SHIELD WILL WORK EAST NORTHEAST THROUGH THE DAY.
THIS WILL MOVE INTO THE FAR SOUTHERN COUNTIES DURING THE
AFTERNOON. DEPENDING ON HOW WARM THE BOUNDARY LAYER IS...THIS
COULD BE EITHER RAIN OR SNOW. CANNOT RULE OUT A BRIEF PERIOD OF
SLEET AT ONSET. BUT DO NOT EXPECT SLEET TO HAVE ANY IMPACT IN THIS
EVENT. AS THE BOUNDARY LAYER COOLS DURING THE EVENING THE
PRECIPITATION WILL CHANGE TO ALL SNOW. MOST ACCUMULATION WILL
OCCUR AFTER DARK WITH THE SNOW ALREADY TAPERING OFF BY 06Z.
THERE WILL BE A SHARP NORTHERN EDGE TO THE PRECIPITATION AND THUS
ACCUMULATIONS. EXPECT 1 TO 3 INCHES IN THE FAR SOUTHEAST COUNTIES
AND THUS HAVE ISSUED A WINTER WEATHER ADVISORY FOR THAT AREA.
ADJACENT COUNTIES WILL LIKELY HAVE LESS THAN AN INCH WITH LITTLE
OR NO SNOW CLOSE TO THE I-71 CORRIDOR.
NORTHEAST WINDS WILL BE GUSTY TODAY INTO THIS EVENING. THESE
WINDS WILL REPLENISH DRY LOW LEVEL AIR WHICH WILL CONTRIBUTE TO
LIMITING THE NORTHWARD EXTENT OF THE PRECIPITATION.
HAVE GONE SLIGHTLY ABOVE MOS FOR BOTH HIGHS AND LOWS. THERE IS THE
POTENTIAL FOR READINGS TO BE EVEN SLIGHTLY WARMER THAN FORECAST AS
SUGGESTED BY NUMEROUS RAP RUNS. IF THIS WERE TO OCCUR THEN
ACCUMULATIONS WOULD BE A BIT LOWER SINCE THERE WOULD BE MORE RAIN
DURING THE AFTERNOON AND THE TRANSITION TO ALL SNOW MIGHT BE
SLIGHTLY LATER.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
HIGH PRESSURE CENTER WILL BE NORTHEAST OF THE REGION DURING THE
PERIOD. THIS WILL BE ABLE TO EXTEND INTO THE FORECAST AREA
RESULTING IN DRY CONDITIONS. LOW LEVEL FLOW WILL SLOWLY VEER.
TEMPERATURES WILL BE WARMING. BASED ON LONG TERM MOS BIAS HAVE
BUMPED UP HIGHS FOR MONDAY. LEANED TOWARDS WARMER MET MOS MONDAY
NIGHT AND GFS MOS FOR TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
STRONG LOW PRESSURE WILL PASS NORTH OF THE REGION DURING THE
MIDDLE OF THE WEEK. APPEARS THAT A PRE-FRONTAL TROUGH WILL SWING
INTO THE FORECAST AREA TUESDAY NIGHT BRINGING A CHANCE OF SHOWERS.
MORE SHOWERS WILL OCCUR ON WEDNESDAY WHEN A COLD FRONT MOVES
THROUGH. NOT EXPECTING MUCH COOLING AS HIGH PRESSURE PASSES SOUTH
OF THE REGION ON THURSDAY. STRONG SOUTHERLY FLOW AHEAD OF THE NEXT
APPROACHING COLD FRONT SHOULD ALLOW TEMPERATURES TO JUMP BACK INTO
THE 60S ON FRIDAY. SHOWERS ASSOCIATED WITH THE FRONT WILL BE
POSSIBLE FRIDAY AFTERNOON INTO FRIDAY NIGHT. HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST WILL DROP READINGS BACK CLOSER TO
NORMAL ON SATURDAY.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
MVFR CIGS ARE WORKING INTO THE TAF SITES FROM THE NORTH THIS
MORNING. HAVE MVFR CIGS AT ALL TAF SITES THIS MORNING EXCEPT FOR
KCVG AND KLUK. KCVG AND KLUK WILL BE ON THE VERY EDGE OF THESE
CIGS. DECIDED TO LEAVE KCVG AND KLUK VFR THIS MORNING.
WIND GUSTS WILL CONTINUE TO INCREASE THROUGH THE DAY BEFORE
TAPERING DOWN OVERNIGHT TONIGHT. A SYSTEM WILL MOVE PRIMARILY SOUTH OF
THE TAF SITES THIS AFTERNOON INTO TONIGHT HOWEVER THE AREA TAF
SITES WILL BE ON THE EDGE OF THE PRECIPITATION SHIELD. KDAY AND
KCMH ARE EXPECTED TO STAY DRY. BROUGHT IN SOME MVFR SNOW TO
KCVG...KLUK...AND KILN. AT KLCK BROUGHT IN SOME LIGHT SNOW HOWEVER
DID NOT REDUCE VSBYS. IN ADDITION BROUGHT IN MVFR CIGS TONIGHT AT
ALL AREA TAF SITES EXCEPT KCMH.
OUTLOOK...MVFR CEILINGS AND VISIBILITIES ARE POSSIBLE MONDAY MORNING.
MVFR CONDITIONS ARE POSSIBLE WITH ANOTHER FRONTAL PASSAGE ON
WEDNESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EDT
MONDAY FOR OHZ081-088.
KY...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EDT
MONDAY FOR KYZ098>100.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...NOVAK
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
500 AM EDT SUN MAR 16 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLOWLY MOVE ACROSS THE GREAT LAKES THROUGH THE
EARLY PART OF THE WEEK. A TROUGH OF LOW PRESSURE WILL DEVELOP
OVER KENTUCKY TODAY AND MOVE OFF TO THE EAST AND WEAKEN BY MONDAY.
A COLD FRONT WILL PUSH INTO THE REGION ON WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
FORECAST AREA WILL BE BETWEEN HIGH PRESSURE MOVING INTO THE GREAT
LAKES AND A LOW TRACKING ACROSS THE GULF COAST STATES. AN INVERTED
TROUGH EXTENDING FROM THE LOW WILL PUSH INTO KENTUCKY TODAY AND
HEAD TOWARDS THE WESTERN SLOPES OF THE APPALACHIANS TONIGHT. A
SHORT WAVE OVER THE SOUTHERN PLAINS WILL GET SHEARED OUT AS IT
MOVES EAST INTO CONFLUENT UPPER LEVEL FLOW THIS AFTERNOON AND
TONIGHT.
PRECIPITATION SHIELD WILL WORK EAST NORTHEAST THROUGH THE DAY.
THIS WILL MOVE INTO THE FAR SOUTHERN COUNTIES DURING THE
AFTERNOON. DEPENDING ON HOW WARM THE BOUNDARY LAYER IS...THIS
COULD BE EITHER RAIN OR SNOW. CANNOT RULE OUT A BRIEF PERIOD OF
SLEET AT ONSET. BUT DO NOT EXPECT SLEET TO HAVE ANY IMPACT IN THIS
EVENT. AS THE BOUNDARY LAYER COOLS DURING THE EVENING THE
PRECIPITATION WILL CHANGE TO ALL SNOW. MOST ACCUMULATION WILL
OCCUR AFTER DARK WITH THE SNOW ALREADY TAPERING OFF BY 06Z.
THERE WILL BE A SHARP NORTHERN EDGE TO THE PRECIPITATION AND THUS
ACCUMULATIONS. EXPECT 1 TO 3 INCHES IN THE FAR SOUTHEAST COUNTIES
AND THUS HAVE ISSUED A WINTER WEATHER ADVISORY FOR THAT AREA.
ADJACENT COUNTIES WILL LIKELY HAVE LESS THAN AN INCH WITH LITTLE
OR NO SNOW CLOSE TO THE I-71 CORRIDOR.
NORTHEAST WINDS WILL BE GUSTY TODAY INTO THIS EVENING. THESE
WINDS WILL REPLENISH DRY LOW LEVEL AIR WHICH WILL CONTRIBUTE TO
LIMITING THE NORTHWARD EXTENT OF THE PRECIPITATION.
HAVE GONE SLIGHTLY ABOVE MOS FOR BOTH HIGHS AND LOWS. THERE IS THE
POTENTIAL FOR READINGS TO BE EVEN SLIGHTLY WARMER THAN FORECAST AS
SUGGESTED BY NUMEROUS RAP RUNS. IF THIS WERE TO OCCUR THEN
ACCUMULATIONS WOULD BE A BIT LOWER SINCE THERE WOULD BE MORE RAIN
DURING THE AFTERNOON AND THE TRANSITION TO ALL SNOW MIGHT BE
SLIGHTLY LATER.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
HIGH PRESSURE CENTER WILL BE NORTHEAST OF THE REGION DURING THE
PERIOD. THIS WILL BE ABLE TO EXTEND INTO THE FORECAST AREA
RESULTING IN DRY CONDITIONS. LOW LEVEL FLOW WILL SLOWLY VEER.
TEMPERATURES WILL BE WARMING. BASED ON LONG TERM MOS BIAS HAVE
BUMPED UP HIGHS FOR MONDAY. LEANED TOWARDS WARMER MET MOS MONDAY
NIGHT AND GFS MOS FOR TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
STRONG LOW PRESSURE WILL PASS NORTH OF THE REGION DURING THE
MIDDLE OF THE WEEK. APPEARS THAT A PRE-FRONTAL TROUGH WILL SWING
INTO THE FORECAST AREA TUESDAY NIGHT BRINGING A CHANCE OF SHOWERS.
MORE SHOWERS WILL OCCUR ON WEDNESDAY WHEN A COLD FRONT MOVES
THROUGH. NOT EXPECTING MUCH COOLING AS HIGH PRESSURE PASSES SOUTH
OF THE REGION ON THURSDAY. STRONG SOUTHERLY FLOW AHEAD OF THE NEXT
APPROACHING COLD FRONT SHOULD ALLOW TEMPERATURES TO JUMP BACK INTO
THE 60S ON FRIDAY. SHOWERS ASSOCIATED WITH THE FRONT WILL BE
POSSIBLE FRIDAY AFTERNOON INTO FRIDAY NIGHT. HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST WILL DROP READINGS BACK CLOSER TO
NORMAL ON SATURDAY.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
VFR AND DRY CONDITIONS WILL START OUT THE TAF PERIOD. WINDS WILL
PICK UP OVERNIGHT AND INTO THE DAY ON SUNDAY. WIND GUSTS WILL
RANGE FROM 20 TO 30 KNOTS AT TIMES ACROSS THE TAF SITES. A SYSTEM
WILL MOVE PRIMARILY SOUTH OF THE TAF SITES SUNDAY INTO SUNDAY
NIGHT. KDAY AND KCMH ARE EXPECTED TO STAY DRY. THE OTHER AREA TAF
SITES ARE EXPECTED TO BE ON THE EDGE OF THE SNOW. HAVE A TEMPO OF
MVFR VSBYS WITH SNOW IN AT KCVG...KLUK...AND KILN AND LIMITED THE
SNOW MENTION TO A VCSH AT KLCK. MVFR CIGS WILL DEVELOP AND MOVE
INTO THE AREA LATE IN THE TAF PERIOD AND WINDS WILL BEGIN TO
DECREASE.
OUTLOOK...MVFR CEILINGS AND VISIBILITIES ARE POSSIBLE SUNDAY
NIGHT. MVFR CONDITIONS ARE POSSIBLE WITH ANOTHER FRONTAL PASSAGE
ON WEDNESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EDT
MONDAY FOR OHZ081-088.
KY...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EDT
MONDAY FOR KYZ098>100.
IN...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...NOVAK
AREA FORECAST DISCUSSION
NWS TULSA OK
625 AM CDT SUN MAR 16 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
UPPER LEVEL STORM SYSTEM WILL MOVE ACROSS THE AREA THIS MORNING
RESULTING IN WIDESPREAD RAIN AND LIKELY IFR CONDITIONS FOR MUCH OF
THE EARLY PART OF THE DAY. WINDS WILL INCREASE OUT OF THE NORTH
THIS MORNING BEHIND A COLD FRONT...WITH SFC GUSTS OF 25-35 KNOTS.
COLDER AIR WILL CAUSE RAIN TO CHANGE TO SNOW ACROSS NW ARKANSAS BY
AFTERNOON WITH VISIBILITY FURTHER REDUCED. PRECIP WILL END BEFORE
00Z IN ALL AREAS WITH IMPROVEMENT TO MVFR CEILINGS FOLLOWED BY
CLEARING SKIES FOR THE END OF THE FORECAST PERIOD.
&&
.PREV DISCUSSION... /ISSUED 323 AM CDT SUN MAR 16 2014/
DISCUSSION...
MAIN CONCERNS TODAY WILL BE THE POTENTIAL OF WINTRY WEATHER FOR
PARTS OF THE AREA ALONG WITH GUSTY NW WINDS.
SURFACE LOW IS CURRENTLY ACROSS FAR SERN OK...WITH A LARGE
PRECIPITATION SHIELD ACROSS THE FORECAST AREA. THIS SURFACE LOW WILL
CONTINUE TO SLOWLY DEEPEN AS IT PULLS FARTHER E INTO AR...WITH GUSTY
NORTHWEST WINDS DEVELOPING ACROSS MUCH OF THE AREA. WE`RE ALREADY
SEEING THIS OCCUR IN PARTS OF NE OK...WITH A RECENT 42MPH GUST AT
THE FORAKER MESONET SITE. CURRENT WIND ADVISORY FOR NE AND ECNTRL OK
LOOKS GOOD...AND WILL LEAVE AS IS FOR NOW.
BIGGEST FORECAST PROBLEM WILL BE TRYING TO NAIL DOWN THE SWITCHOVER
TO SLEET/SNOW TODAY...AND WHERE ANY POTENTIAL ACCUMULATIONS MAY
OCCUR. USING A 50/50 MIX OF THE NAM/ECMWF FOR THE TEMP/MOISTURE
PROFILES...AREAS EAST OF HIGHWAY 75 IN NE OK COULD START SEEING A
MIX LATER THIS MORNING...WITH MOSTLY SNOW EXPECTED DURING THE
AFTERNOON FOR NW AR AND FAR ADJACENT AREAS OF NE OK. THE MORE RECENT
HOURLY RUNS OF THE HRRR AND RAP HAVE DOWNPLAYED ACCUMULATIONS ACROSS
NE OK...AND ARE FOCUSING SNOW ACCUMULATIONS MAINLY ON PARTS OF NW AR
FOR THIS AFTERNOON...MORE INLINE WITH THE NAM/ECMWF.
ANY SNOW WILL BE FALLING DURING THE DAYLIGHT HOURS AND GIVEN THE
RELATIVELY WARM GROUND CONDITIONS...IT WILL TAKE GOOD SNOWFALL RATES
FOR ACCUMULATIONS TO OCCUR. AT THIS TIME...WILL OPT FOR A WINTER
WEATHER ADVISORY FOR CARROLL AND MADISON COUNTIES...WHERE AROUND 1-2
INCHES OF SNOW APPEAR LIKELY. DAYSHIFT WILL NEED TO MONITOR THIS
CLOSELY THIS MORNING...AND MAY NEED TO ADJUST ADVISORY FARTHER WEST.
REMAINDER OF THE WEEK LOOKS RELATIVELY QUIET. TEMPS ARE EXPECTED TO
WARM NICELY BY TUESDAY AHEAD OF A WEAK COLD FRONT THAT WILL KNOCK
TEMPS BACK DOWN A FEW DEGREES FOR WEDNESDAY. ANOTHER WEAK BOUNDARY
WILL MOVE INTO THE AREA BY FRIDAY...AND MAY BRING A SMALL CHANCE OF
PRECIPITATION.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY UNTIL 7 PM SUNDAY FOR OKZ054-OKZ055-OKZ056-OKZ057-
OKZ058-OKZ059-OKZ060-OKZ061-OKZ062-OKZ063-OKZ064-OKZ065-
OKZ066-OKZ067-OKZ070-OKZ071.
AR...WINTER WEATHER ADVISORY FROM 10 AM SUNDAY TO 10 PM SUNDAY FOR
ARZ002-ARZ011.
&&
$$
AVIATION...14
AREA FORECAST DISCUSSION
NWS TULSA OK
323 AM CDT SUN MAR 16 2014
.DISCUSSION...
MAIN CONCERNS TODAY WILL BE THE POTENTIAL OF WINTRY WEATHER FOR
PARTS OF THE AREA ALONG WITH GUSTY NW WINDS.
SURFACE LOW IS CURRENTLY ACROSS FAR SERN OK...WITH A LARGE
PRECIPITATION SHIELD ACROSS THE FORECAST AREA. THIS SURFACE LOW WILL
CONTINUE TO SLOWLY DEEPEN AS IT PULLS FARTHER E INTO AR...WITH GUSTY
NORTHWEST WINDS DEVELOPING ACROSS MUCH OF THE AREA. WE`RE ALREADY
SEEING THIS OCCUR IN PARTS OF NE OK...WITH A RECENT 42MPH GUST AT
THE FORAKER MESONET SITE. CURRENT WIND ADVISORY FOR NE AND ECNTRL OK
LOOKS GOOD...AND WILL LEAVE AS IS FOR NOW.
BIGGEST FORECAST PROBLEM WILL BE TRYING TO NAIL DOWN THE SWITCHOVER
TO SLEET/SNOW TODAY...AND WHERE ANY POTENTIAL ACCUMULATIONS MAY
OCCUR. USING A 50/50 MIX OF THE NAM/ECMWF FOR THE TEMP/MOISTURE
PROFILES...AREAS EAST OF HIGHWAY 75 IN NE OK COULD START SEEING A
MIX LATER THIS MORNING...WITH MOSTLY SNOW EXPECTED DURING THE
AFTERNOON FOR NW AR AND FAR ADJACENT AREAS OF NE OK. THE MORE RECENT
HOURLY RUNS OF THE HRRR AND RAP HAVE DOWNPLAYED ACCUMULATIONS ACROSS
NE OK...AND ARE FOCUSING SNOW ACCUMULATIONS MAINLY ON PARTS OF NW AR
FOR THIS AFTERNOON...MORE INLINE WITH THE NAM/ECMWF.
ANY SNOW WILL BE FALLING DURING THE DAYLIGHT HOURS AND GIVEN THE
RELATIVELY WARM GROUND CONDITIONS...IT WILL TAKE GOOD SNOWFALL RATES
FOR ACCUMULATIONS TO OCCUR. AT THIS TIME...WILL OPT FOR A WINTER
WEATHER ADVISORY FOR CARROLL AND MADISON COUNTIES...WHERE AROUND 1-2
INCHES OF SNOW APPEAR LIKELY. DAYSHIFT WILL NEED TO MONITOR THIS
CLOSELY THIS MORNING...AND MAY NEED TO ADJUST ADVISORY FARTHER WEST.
REMAINDER OF THE WEEK LOOKS RELATIVELY QUIET. TEMPS ARE EXPECTED TO
WARM NICELY BY TUESDAY AHEAD OF A WEAK COLD FRONT THAT WILL KNOCK
TEMPS BACK DOWN A FEW DEGREES FOR WEDNESDAY. ANOTHER WEAK BOUNDARY
WILL MOVE INTO THE AREA BY FRIDAY...AND MAY BRING A SMALL CHANCE OF
PRECIPITATION.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 41 26 59 42 / 80 10 0 0
FSM 52 28 56 38 / 90 20 0 0
MLC 47 26 59 42 / 70 10 0 0
BVO 41 21 61 37 / 60 10 0 0
FYV 45 21 56 35 / 90 20 0 0
BYV 44 21 55 37 / 90 20 0 0
MKO 45 26 58 39 / 80 10 0 0
MIO 41 21 57 39 / 80 10 0 0
F10 43 26 60 41 / 80 10 0 0
HHW 52 29 57 39 / 50 10 0 0
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...WIND ADVISORY UNTIL 7 PM SUNDAY FOR OKZ054-OKZ055-OKZ056-OKZ057-
OKZ058-OKZ059-OKZ060-OKZ061-OKZ062-OKZ063-OKZ064-OKZ065-
OKZ066-OKZ067-OKZ070-OKZ071.
AR...WINTER WEATHER ADVISORY FROM 10 AM SUNDAY TO 10 PM SUNDAY FOR
ARZ002-ARZ011.
&&
$$
SHORT TERM...14
LONG TERM....18
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
848 PM CDT MON MAR 17 2014
.UPDATE...
BACK EDGE OF LOW DECK EXTENDS FROM PORTLAND DOWN THROUGH WESTERN
DAVIDSON COUNTY AND ON DOWN TO LINDEN. BACK EDGE OF LOW CLOUDS HAS
BEEN SLOWLY WORKING EASTWARD. NOT EXPECTING CLOUDS TO CLEAR
EASTERN AREAS AND PLATEAU OVERNIGHT. MAY SEE SOME REDEVLOPMENT
TAKE PLACE WESTERN AREAS AS WELL AS FOGGY CONDITIONS ALL AREAS. WILL
UPDATE THE FORECAST AND INCLUDE PATCHY FOG OVERNIGHT FOR ALL OF
MIDDLE TENNESSEE. COULD BE DENSE ALONG PLATEAU. WILL NEED TO KEEP
TABS ON TEMP/DEWPOINT SPREADS.
.CLIMATE...THE HIGH TODAY IN NASHVILLE WAS 42 DEGREES. IT WAS
CHILLY BUT NO WHERE NEAR THE RECORD FOR THE LOWEST DAILY HIGH FOR
THIS DATE WHICH IS 30 DEGREES SET WAY BACK IN 1892. THAT WAS ALSO
THE DAY IT SNOWED 17 INCHES (MARCH 17TH 1892) WHICH IS STILL THE
LARGEST SNOWFALL IN A 24 HOUR PERIOD AT NASHVILLE.
&&
.PREV DISCUSSION... /ISSUED 646 PM CDT MON MAR 17 2014/
UPDATE...FOR 00Z AVIATION FORECAST
AVIATION...
CLARKSVILLE HAS GONE SCATTERED FOR THE TIME BEING. BACK EDGE OF LOW
CLOUD DECK ABOUT 40 MILES NORTHWEST OF THE NASHVILLE AIRPORT AT 23Z.
CLOUDS WILL CONTINUE TO TRY AND ERODE FROM THE WEST OVER THE NEXT
SEVERAL HOURS BUT SURFACE INVERTED TROUGH ALIGNED ALONG SMOKIES
HAS MOVED LITTLE LAST SEVERAL HOURS SO THINK EASTERN AREAS OF MID
STATE AND PLATEAU WILL HAVE LOW CLOUDS AND VISIBILITIES OVERNIGHT
WITH LIFR CONDITIONS AT CROSSVILLE. THE MAIN PROBLEM TONIGHT IS
THAT EVEN THOUGH WE ARE SEEING EROISON TAKING PLACE IN LOW CLOUD
COVER IN WESTERN AREAS THE LOW LEVEL MOISTURE ISN`T GETTING SCOURED
OUT. SO THINK WE COULD SEE REDEVELOPMENT IN THE OVERNIGHT HOURS AT
BOTH CLARKSVILLE AND NASHVILLE WITH AT MVFR CONDITIONS DEVELOPING
AFTER MIDNIGHT IN BOTH CEILING AND VISIBILITIES. THIS BASED ON
FORECAST GFS BUFKIT FORECAST SOUNDINGS AND LATEST RUC SOUNDING.
SURFACE WINDS PICK UP FROM THE SOUTH TUESDAY AFTERNOON AS CENTRAL
PLAINS SYSTEM BEGINS TO HEAD THIS WAY WITH A TIGHTENING PRESSURE GRADIENT.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
BOYD
01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
646 PM CDT MON MAR 17 2014
.UPDATE...FOR 00Z AVIATION FORECAST
&&
.AVIATION...
CLARKSVILLE HAS GONE SCATTERED FOR THE TIME BEING. BACK EDGE OF LOW
CLOUD DECK ABOUT 40 MILES NORTHWEST OF THE NASHVILLE AIRPORT AT 23Z.
CLOUDS WILL CONTINUE TO TRY AND ERODE FROM THE WEST OVER THE NEXT
SEVERAL HOURS BUT SURFACE INVERTED TROUGH ALIGNED ALONG SMOKIES
HAS MOVED LITTLE LAST SEVERAL HOURS SO THINK EASTERN AREAS OF MID
STATE AND PLATEAU WILL HAVE LOW CLOUDS AND VISIBILITIES OVERNIGHT
WITH LIFR CONDITIONS AT CROSSVILLE. THE MAIN PROBLEM TONIGHT IS
THAT EVEN THOUGH WE ARE SEEING EROISON TAKING PLACE IN LOW CLOUD
COVER IN WESTERN AREAS THE LOW LEVEL MOISTURE ISN`T GETTING SCOURED
OUT. SO THINK WE COULD SEE REDEVELOPMENT IN THE OVERNIGHT HOURS AT
BOTH CLARKSVILLE AND NASHVILLE WITH AT MVFR CONDITIONS DEVELOPING
AFTER MIDNIGHT IN BOTH CEILING AND VISIBILITIES. THIS BASED ON
FORECAST GFS BUFKIT FORECAST SOUNDINGS AND LATEST RUC SOUNDING.
SURFACE WINDS PICK UP FROM THE SOUTH TUESDAY AFTERNOON AS CENTRAL
PLAINS SYSTEM BEGINS TO HEAD THIS WAY WITH A TIGHTENING PRESSURE GRADIENT.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
BOYD
01
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
410 PM CDT SUN MAR 16 2014
.DISCUSSION...
THE FOCUS OF THIS FORECAST WILL BE THE CHANCE FOR FREEZING DRIZZLE
AND POSSIBLY SLEET THIS EVENING AND EARLY MONDAY MORNING.
THE SURFACE LOW THAT WAS RESPONSIBLE FOR TODAY`S WET WEATHER WILL
CONTINUE ON ITS EASTWARD PATH ACROSS NORTHERN ALABAMA AND GEORGIA
THIS EVENING. AS IT DOES THIS ANOTHER WAVE OF PRECIP IS EXPECTED
TO DEVELOP ON ITS NORTHWEST SIDE AND MOVE ACROSS THE MID-STATE.
MOST RECENT MODELS RUNS INCLUDING THE HRRR INDICATE A BAND OF
PRECIP DEVELOPING JUST BEFORE MIDNIGHT THAT WILL STRETCH FROM THE
SOUTHWESTERN CORNER TO THE NORTHEASTERN CORNER OF THE CWA...WHICH
WOULD ALIGN THE HEAVIEST PRECIP ACROSS PERRY, DAVIDSON, AND UP
INTO MACON COUNTY. HOWEVER THIS BAND IS EXPECTED TO BRING ONLY A
SMALL AMOUNT OF QPF...LESS THAN 0.20 INCHES. MOST OF THE AREA OVER
WHICH THIS PRECIP IS EXPECTED TO FALL IS FORECAST TO REMAIN JUST
ABOVE FREEZING TONIGHT. IT`S THE AREA IN NORTHWEST MIDDLE
TENNESSEE INCLUDING STEWART, MONTGOMERY, AND HOUSTON COUNTIES THAT
COULD SEE SOME WINTRY PRECIP AS TEMPERATURES FALL INTO THE UPPER
20S. THIS COULD MEAN THESE AREAS AND POSSIBLY AREAS JUST SOUTH OF
THERE...DOWN TO THE I-40 CORRIDOR COULD SEE SLEET WITH THE
HEAVIEST PRECIP...THEN FREEZING DRIZZLE LATE TONIGHT AS PRECIP
DIMINISHES AND MOVES EAST. SOUNDINGS SUPPORT THIS IDEA WITH A
SATURATED LOWER LEVEL AND FAIRLY DEEP WARM NOSE UNTIL EARLY MONDAY
MORNING. BY THE TIME THE WARM NOSE ERODES THE SATURATED LAYER
APPEARS ONLY DEEP ENOUGH TO PRODUCE FREEZING DRIZZLE. SINCE ONLY
LIGHT PRECIP IS EXPECTED AND ROADWAYS WILL LIKELY BE TOO WARM TO
COLLECT ANY ACCUMULATION THE SPS THAT MENTIONED SOME POSSIBLE
SLICK ROADWAYS MONDAY MORNING SHOULD CONTINUE TO SUFFICE..
CONDITIONS SHOULD QUICKLY IMPROVE OVER THE WEST ON MONDAY AS
TEMPERATURES RISE TO AROUND 50 DEGREES. LIGHT RAIN SHOWERS MAY
TAKE THEIR TIME EXITING THE CUMBERLAND PLATEAU...BUT SHOULD BE
GONE BY MONDAY EVENING.
MONDAY NIGHT INTO TUESDAY CLOUDS SHOULD BEGIN TO THIN OUT. THIS
WILL ALLOW TEMPERATURES TO WARM INTO THE MID 60S ON TUESDAY. THE
NEXT CHANCE OF PRECIP WILL ENTER THE FORECAST TUESDAY NIGHT AS THE
TAIL END OF A WEAK COLD FRONT MOVES THROUGH THE TENNESSEE VALLEY.
NOT A LOT OF MOISTURE ASSOCIATED WITH THE FRONT AS IT ENTERS OUR
AREA...HOWEVER MOISTURE TRANSPORT INCREASES AS IT MOVES
EAST...WHICH COULD MEAN AT LEAST A CHANCE OF SHOWERS DURING THE DAY
ON WEDNESDAY. NO REAL CHANGE IN TEMPERATURES DUE TO THE FRONT AND
AS IT EXITS WEDNESDAY AFTERNOON THE UPPER FLOW BECOMES ZONAL AND
ALLOWS FOR A PLEASANT THURSDAY AND FRIDAY WITH TEMPERATURES
CLIMBING INTO THE 70S ON FRIDAY AFTERNOON.
FRIDAY NIGHT WILL BRING THE FINAL CHANCE OF PRECIP IN THIS
FORECAST...THREW IN ISO T AS THE FRONT MOVES THROUGH OVERNIGHT
FRIDAY NIGHT AS THE AIRMASS IN PLACE COULD BE UNSTABLE ENOUGH TO
SUPPORT A STORM OR TWO. THIS SYSTEM IS FORECAST TO BE EAST OF THE
MID STATE BY SATURDAY EVENING.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 32 52 34 65 / 60 10 10 10
CLARKSVILLE 28 50 34 65 / 50 10 10 10
CROSSVILLE 35 49 34 59 / 70 40 20 10
COLUMBIA 36 51 32 65 / 60 10 10 10
LAWRENCEBURG 37 51 34 63 / 60 20 10 10
WAVERLY 30 51 36 62 / 50 10 10 10
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
11
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1230 PM CDT SUN MAR 16 2014
.AVIATION 18Z DISCUSSION...
FRONTAL BOUNDARY IS NEARLY STATIONARY AND IS LOCATED ALONG THE
TN/AL BORDER. SFC LOW PRESSURE OVER NE MS WILL BE MOVING EAST THIS
AFTERNOON AND THE FRONT WILL BEGIN TO MOVE SOUTHWARD. UPPER LEVEL
SHORTWAVE OVER AR WILL BE MOVING EAST AND WILL BRING A CONTINUING
SHOT OF RAINFALL TO THE AREA THROUGH 00Z. THE PRECIPITATION WILL
BEGIN TO LESSEN IN COVERAGE AND INTENSITY THEREAFTER. AS COLDER
AIR CONTINUES TO MOVE IN FROM THE NW...AREAS NEAR CKV COULD SEE
SOME FREEZING DRIZZLE AFT 06Z. TEMPS WILL BE COLD ENOUGH FOR VERY LIGHT
ICE ACCUM THROUGH 12Z. MVFR CONDITIONS WILL RETURN AFT 12Z...EXCEPT
AT CSV WHERE IFR WILL REMAIN THROUGH THE ENTIRE TAF.
&&
.PREV DISCUSSION... /ISSUED 1012 AM CDT SUN MAR 16 2014/
UPDATE...
LLJ IS STRONGEST EAST OF THE SFC LOW CURRENTLY LOCATED OVER FAR
NORTHWESTERN AL. AS A RESULT...WE ARE SEEING A DECREASE IN COVERAGE
OF THE RAINFALL ACROSS MUCH OF THE MID STATE RIGHT NOW. BUT
LOOKING UPSTREAM...A SHORTWAVE EXISTS OVER AR WITH ANOTHER AREA OF
WIDESPREAD RAINFALL ACROSS WESTERN TN AND KY INTO MO AND AR. AS
THE SHORTWAVE MOVES EASTWARD TODAY...THE RAINFALL COVERAGE WILL
AGAIN FILL IN. THEREFORE...THE GRID TREND TO KEEP 50 POPS
SOUTHWEST AND LIKELY TO CATEGORICAL POPS ELSEWHERE...CONTINUES TO
LOOK REASONABLE.
OTW...STILL LOOKING AT THE POTENTIAL FOR THUNDER ACROSS THE SOUTH
THIS AFTERNOON. SFC SHOWALTERS TO GO SLIGHTLY NEGATIVE BY 18Z.
AS FOR TODAY`S TEMPS...FALLING TEMPS STILL EXPECTED TODAY. BY LATE
AFTERNOON TEMPS SHOULD RANGE FROM THE UPPER 30S NORTHWEST...TO THE
UPPER 50S SOUTHWEST. THE COLD FRONT ACROSS OUR FAR SOUTH NOW WILL
REMAIN NEARLY STATIONARY UNTIL THIS AFTERNOON WHEN THE APPROACHING
SHORTWAVE FINALLY KICKS IT SLOWLY SOUTHWARD.
FOR NOW...NO CHANGES TO THE GRIDS. WILL PAY CLOSE ATTENTION TO THE
TEMPS HOWEVER AS A STEEP GRADIENT IS EXPECTED TO SET UP.
PREV DISCUSSION... /ISSUED 757 AM CDT SUN MAR 16 2014/
UPDATE...MASSAGED PRECIP AND POP GRIDS TO INDICATE A GENERAL
TREND THAT CLOSELY PARALLELS LATEST RADAR LOOPS AND HRRR. ALSO, IN
LIGHT OF LATEST FORECAST RUC SOUNDINGS FOR THIS AFTERNOON, HAVE
EXPANDED THE POSSIBILITY FOR ISOLATED THUNDER A TAD FURTHER NORTH
(FOR THE 18Z TO 00Z PERIOD). OTHERWISE, NO CHANGE.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1012 AM CDT SUN MAR 16 2014
.UPDATE...
LLJ IS STRONGEST EAST OF THE SFC LOW CURRENTLY LOCATED OVER FAR
NORTHWESTERN AL. AS A RESULT...WE ARE SEEING A DECREASE IN COVERAGE
OF THE RAINFALL ACROSS MUCH OF THE MID STATE RIGHT NOW. BUT
LOOKING UPSTREAM...A SHORTWAVE EXISTS OVER AR WITH ANOTHER AREA OF
WIDESPREAD RAINFALL ACROSS WESTERN TN AND KY INTO MO AND AR. AS
THE SHORTWAVE MOVES EASTWARD TODAY...THE RAINFALL COVERAGE WILL
AGAIN FILL IN. THEREFORE...THE GRID TREND TO KEEP 50 POPS
SOUTHWEST AND LIKELY TO CATEGORICAL POPS ELSEWHERE...CONTINUES TO
LOOK REASONABLE.
OTW...STILL LOOKING AT THE POTENTIAL FOR THUNDER ACROSS THE SOUTH
THIS AFTERNOON. SFC SHOWALTERS TO GO SLIGHTLY NEGATIVE BY 18Z.
AS FOR TODAY`S TEMPS...FALLING TEMPS STILL EXPECTED TODAY. BY LATE
AFTERNOON TEMPS SHOULD RANGE FROM THE UPPER 30S NORTHWEST...TO THE
UPPER 50S SOUTHWEST. THE COLD FRONT ACROSS OUR FAR SOUTH NOW WILL
REMAIN NEARLY STATIONARY UNTIL THIS AFTERNOON WHEN THE APPROACHING
SHORTWAVE FINALLY KICKS IT SLOWLY SOUTHWARD.
FOR NOW...NO CHANGES TO THE GRIDS. WILL PAY CLOSE ATTENTION TO THE
TEMPS HOWEVER AS A STEEP GRADIENT IS EXPECTED TO SET UP.
&&
.PREV DISCUSSION... /ISSUED 757 AM CDT SUN MAR 16 2014/
UPDATE...MASSAGED PRECIP AND POP GRIDS TO INDICATE A GENERAL
TREND THAT CLOSELY PARALLELS LATEST RADAR LOOPS AND HRRR. ALSO, IN
LIGHT OF LATEST FORECAST RUC SOUNDINGS FOR THIS AFTERNOON, HAVE
EXPANDED THE POSSIBILITY FOR ISOLATED THUNDER A TAD FURTHER NORTH
(FOR THE 18Z TO 00Z PERIOD). OTHERWISE, NO CHANGE.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
757 AM CDT SUN MAR 16 2014
.UPDATE...MASSAGED PRECIP AND POP GRIDS TO INDICATE A GENERAL
TREND THAT CLOSELY PARALLELS LATEST RADAR LOOPS AND HRRR. ALSO, IN
LIGHT OF LATEST FORECAST RUC SOUNDINGS FOR THIS AFTERNOON, HAVE
EXPANDED THE POSSIBILITY FOR ISOLATED THUNDER A TAD FURTHER NORTH
(FOR THE 18Z TO 00Z PERIOD). OTHERWISE, NO CHANGE.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
19
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1244 PM CDT SUN MAR 16 2014
.DISCUSSION...SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...VFR CONDITIONS SHOULD PREVAIL...ALTHOUGH COULD NOT
RULE OUT A MVFR CIG TEMPORARILY KCRP OR KVCT IF PRECIPITATION IS
MODERATE TO HEAVY THIS AFTERNOON (BUT DO NOT EXPECT THAT). RAIN IS
CAUSING HAVOC WITH WINDS...AS WINDS DIMINISH IN RAIN AT TERMINALS.
WILL HAVE THE POTENTIAL FOR RAIN THROUGH ABOUT 22Z KCRP AND KVCT
BEFORE IT ENDS (HAVE TEMPO)...WITH WINDS NORTHERLY AND GUSTY ALL
TERMINALS THROUGH ABOUT 01Z/02Z. WINDS WILL STAY A BIT GUSTY IN
THE EVENING (BUT LOWER) THEN SHOULD START SEEING THE END OF GUSTY
WINDS BETWEEN 06Z AND 12Z. MAY SEE A FEW MID LEVEL SCATTERED
CLOUDS MONDAY AFTER SUNRISE...BUT OTHERWISE WILL REMAIN VFR AS
DRIER AIR MOVES INTO THE REGION.
&&
.PREV DISCUSSION... /ISSUED 1027 AM CDT SUN MAR 16 2014/
DISCUSSION...DID A FEW UPDATES TO THE FORECAST. SOME
CONVECTION/STRATI-FORM RAIN REMAINING AROUND THE AREA DUE TO POTENT
JET SEEN ON SATELLITE IMAGERY. ACTIVITY SHOULD BEGIN TO DIMINISH
THIS AFTERNOON AS IMPACTS FROM UPPER JET END. FRONT THROUGH
NORTHERN AREAS NOW...AND GOING THROUGH SOUTHERN AREAS BY NOON.
LEFT SOME CONVECTION IN FOR THE AFTERNOON MAINLY NEAR THE COAST
(AND OFFSHORE). WIND ADVISORY CRITERION NOT THERE FOR WEBB COUNTY
SO WILL CANCEL IT. FORECAST HIGHS A BIT TRICKY OUT WEST WHERE
SATELLITE SHOWING SOME CLEARING BUT WILL PROBABLY SEE MORE CLOUDS
COME BACK. IN SHORT...DID SOME MINOR ADJUSTMENTS FOR HIGHS
TODAY...AND ADJUSTED OTHER GRIDS AS-NEEDED FOR LATER TODAY AND
TONIGHT TO BETTER FIT LATEST OBSERVATIONS AND FORECAST TRENDS. ALL
PRODUCTS UPDATED AND OUT.
MARINE...STARTED SCA A BIT EARLIER AS WINDS ON RUC AND NEW NAM WERE
GOING HIGHER EARLIER. NORTHWEST WINDS CLEARED OUT THE SEA FOG SO
THAT ADVISORY HAS BEEN CANCELLED EARLIER. KEPT END TIMING OF SCA THE
SAME FOR NOW...BUT WILL LOOK AT ANY ADJUSTMENTS FOR THE AFTERNOON
PACKAGE. PUT LOW CHANCE POPS IN FOR THE AFTERNOON PACKAGE. THAT IS
IT FOR NOW.
PREV DISCUSSION... /ISSUED 553 AM CDT SUN MAR 16 2014/
DISCUSSION...HAVE ADJUSTED POP/WEATHER FORECAST FOR TODAY BASED
ON CURRENT RADAR TRENDS. CHANCE POPS ACROSS THE AREA WITH SLIGHT
CHANCE THUNDERSTORMS. CONVECTION IS DEVELOPING ALONG CAPE GRADIENT
WITH INITIAL BOUNDARY. CAPE VALUES RATHER LOW...BELOW 1000
J/KG...BUT SFC-6 KM BULK SHEAR VALUES AROUND 60KT. MESO MODELS NOT
HANDLING THE SITUATION WELL AT ALL. THINKING THOUGH IS THAT AS THE
UPPER JET SAGS SOUTH THE CONVECTION SHOULD WEAKEN A BIT...BUT WILL
LIKELY SEE AT LEAST SHOWER ACTIVITY PROGRESS EASTWARD ACROSS THE
FORECAST AREA THROUGH THE MORNING.
ALSO SEE 12Z AVIATION DISCUSSION BELOW.
AVIATION...WILL ADD CONVECTION INTO ALL TAFS WITH 12Z UPDATE THIS
MORNING. LRD SHOULD ONLY SEE CONVECTION POTENTIAL FOR THE NEXT
COUPLE OF HOURS...BUT ALL OTHER SITES COULD SEE AT LEAST SHOWERS
AND SOME THUNDERSTORM POTENTIAL THROUGH THE MORNING. OTHERWISE
SEEMS REMAIN ON TRACK WITH COLD FRONT MOVING THROUGH DURING THE
MORNING HOURS. EXPECTED STRONG NORTHERLY WINDS TO DEVELOP FOR ALL
SITES AND GRADUALLY WEAKEN TONIGHT. EXPECT MVFR TO IFR CIGE PRE
FRONT...AND VFR POST FRONT.
PREV DISCUSSION... /ISSUED 411 AM CDT SUN MAR 16 2014/
SHORT TERM (TODAY THROUGH MONDAY)...DIFFICULT FORECAST FOR THE
FIRST 18 HOURS OR SO OF THE FORECAST PERIOD. INITIALLY...HAVE FOG
SPREAD ACROSS MUCH OF SOUTH TEXAS...BUT MOSTLY A LIGHT FOG
SITUATION. SOME PATCHY...BRIEF DENSE FOG ON THE ISLANDS.
ADDITIONALLY...SEEING SOME VIRGA...OR MAYBE SPRINKLES DEVELOPING
AHEAD OF THE FRONT...WITH A FEW SHOWERS AND A COUPLE OF
THUNDERSTORMS NORTHWEST OF THE FORECAST AREA WITH INITIAL WIND
SHIFT/LEADING TROUGH. COULD BE A WEAK COLD FRONT ACROSS FROM DEL
RIO TO AUSTIN...BUT MAIN FRONT WITH COLDER/DRIER AIR IS STILL BACK
AROUND MIDLAND TO WICHITA FALLS. SURFACE THETA E FORECAST WOULD
INDICATE THE STRONGER FRONT ACCELERATING FASTER TOWARD SOUTH TEXAS
THIS MORNING...MAYBE CATCHING THE WEAKER FRONT BY THE COAST.
THAT SAID...STILL LOOK FOR A WIND SHIFT BEGINNING NORTHWEST ZONES
BY 11-12Z...BUT SURGE OF STRONGER WINDS/COOLER TEMPS WONT BE UNTIL
MID MORNING WEST. SHOULD SEE FRONTAL PASSAGE THROUGH TO THE COAST
BY 18Z. HAVE A CHANCE OF SHOWERS ACROSS THE AREA THROUGH THE
MORNING WITH A SLIGHT CHANCE OF THUNDERSTORMS EAST...BUT MAY NEED
TO EXPAND THUNDER POTENTIAL WEST IF CURRENT RADAR TRENDS CONTINUE.
LEFT EXIT REGION OF UPPER JET CERTAINLY HELPING IN CONVECTION
DEVELOPMENT THIS MORNING. THE JET DOES GRADUALLY SINK SOUTH
THROUGH THE MORNING AND SHOULD TAKE THUNDER POTENTIAL WITH IT.
HRRR MODEL DOING A VERY POOR JOB THIS MORNING WITH INITIALIZING
PRECIP...NOT INDICATING CONVECTION BETWEEN DEL RIO AND LAREDO AT
ALL.
ALL OF THE ABOVE LEADS TO A TRICKY TEMPERATURE AND WIND FORECAST
FOR TODAY. FIRST...WIND. PRECIOUS MODEL RUNS HAD ALL BEEN PROGGING
A VERY STRONG BURST OF WINDS AT 925MB IN WESTERN ZONES FOR
TODAY...00Z AND 06Z RUNS HAVE BACKED OFF SIGNIFICANTLY ON
THIS...AND WHAT STRONGER WINDS THEY DO HAVE LEFT ARE FARTHER WEST
OVER EASTERN MEXICO. THIS BRINGS INTO QUESTION WHETHER WEB COUNTY
CAN REALIZE THE WINDS FOR THE WIND ADVISORY CURRENTLY IN EFFECT.
THINKING ON THAT...THERE IS STILL A CHANCE FOR AREAS NEAR THE RIO
GRANDE TO REACH ADVISORY CRITERIA BRIEFLY...SO WILL LET THE
ADVISORY RIDE FOR NOW. WHILE WINDY CONDITIONS ARE EXPECTED...MOST
OF WEBB COUNTY...AS WELL AS THE REST OF THE FORECAST AREA WILL
LIKELY NOT BE GUSTING TO 40 MPH. TRICKY TEMPERATURE FORECAST TODAY
TOO...BUT THINK MOST AREAS WILL BE IN THE UPPER 60S AND LOWER 70S.
WITH COOLER HIGHS...HAVE CANCELLED RED FLAG WATCH FOR THE
AREA...THINKING CONDITIONS WILL NOT BE DRY ENOUGH FOR A CRITICAL
FIRE DANGER.
THE REST OF THE SHORT TERM FORECAST IS PRETTY BENIGN. PRECIP
IF IT LINGERS INTO THE EVENING SHOULD END PRETTY EARLY. WILL
REMAIN CLOUDY TONIGHT WITH UPPER LOW STILL OVER THE AREA...BUT
SHOULD SEE TEMPS INTO THE 40S FOR MOST OF US.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...DRY AND COOL MON NIGHT
UNDER CLEAR SKIES. THE LOW LEVEL RIDGE AXIS DOES SHIFT EAST MON EVE
AND A WEAK SOUTHERLY FLOW DEVELOPS LATE MON NIGHT...THEN STRENGTHENS
TUE. SUNNY AND DRY TUE....WARM AWAY FROM THE IMMEDIATE COAST GIVEN
THE SOUTH TO SOUTHWEST FLOW...WITH HIGHS IN THE MID TO UPPER 80S
INLAND...POSSIBLY NEAR 90 POSSIBLE ACROSS SOME AREAS OF BRUSH
COUNTRY AND RIO GRANDE. THERMAL GRADIENT BETWEEN COOL SHELF WATERS
AND INLAND TEMPS ON TUE WILL LEAD TO BREEZY TO WINDY CONDITIONS
ACROSS THE SOUTHERN COASTAL BEND AND POSSIBLE ELEVATED FIRE WEATHER
CONDITIONS...AS MOISTURE RETURN IS RATHER LIMITED. THE TAIL END OF A
WEAK COLD FRONT MAY SLIP INTO THE AREA ON WEDNESDAY AND STALL...
FOLLOWED CLOSER TO A GFS ENSEMBLE MEAN SOLUTION. UPPER LEVEL PATTERN
NOT COMPLETELY FAVORABLE TO DRIVE FRONT THROUGH THE AREA.
NEVERTHELESS...LOW LEVEL FLOW BACKED MORE EASTERLY WED AND THU WILL
RESULT IN SLIGHTLY COOLER TEMPS. MOISTURE RETURN AHEAD OF THE FRONT
CONTINUES TO APPEAR RATHER LIMITED...SO NO MENTION OF PRECIP
MENTIONED AT THIS TIME WED OR THU. ONSHORE FLOW AND MOISTURE DEPTH
DOES INCREASE FRI ACROSS COASTAL BEND AND SAT ACROSS MUCH OF THE
CWA...WITH PWATS INCREASING TO AROUND 1.4-1.5 INCHES. HOWEVER
FORCING IS RATHER LIMITED THIS FAR SOUTH SO AT THIS TIME HAVE CHOSE
NOT TO MENTION PRECIP IN THE OFFICIAL FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 72 45 65 44 85 / 40 10 10 0 0
VICTORIA 67 41 63 41 82 / 40 10 10 0 0
LAREDO 70 45 71 49 90 / 40 10 0 0 0
ALICE 71 44 67 41 89 / 40 10 0 0 0
ROCKPORT 67 46 62 49 75 / 40 10 10 0 0
COTULLA 68 41 70 42 86 / 40 10 0 0 0
KINGSVILLE 73 45 67 40 87 / 40 10 10 0 0
NAVY CORPUS 69 46 64 51 78 / 40 10 10 0 0
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 10 AM CDT MONDAY FOR THE FOLLOWING
ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS...
BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR...
COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...
COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL
OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20
TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP
CHANNEL FROM 20 TO 60 NM.
&&
$$
GW/86...AVIATION
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1027 AM CDT SUN MAR 16 2014
.DISCUSSION...DID A FEW UPDATES TO THE FORECAST. SOME
CONVECTION/STRATI-FORM RAIN REMAINING AROUND THE AREA DUE TO POTENT
JET SEEN ON SATELLITE IMAGERY. ACTIVITY SHOULD BEGIN TO DIMINISH
THIS AFTERNOON AS IMPACTS FROM UPPER JET END. FRONT THROUGH
NORTHERN AREAS NOW...AND GOING THROUGH SOUTHERN AREAS BY NOON.
LEFT SOME CONVECTION IN FOR THE AFTERNOON MAINLY NEAR THE COAST
(AND OFFSHORE). WIND ADVISORY CRITERION NOT THERE FOR WEBB COUNTY
SO WILL CANCEL IT. FORECAST HIGHS A BIT TRICKY OUT WEST WHERE
SATELLITE SHOWING SOME CLEARING BUT WILL PROBABLY SEE MORE CLOUDS
COME BACK. IN SHORT...DID SOME MINOR ADJUSTMENTS FOR HIGHS
TODAY...AND ADJUSTED OTHER GRIDS AS-NEEDED FOR LATER TODAY AND
TONIGHT TO BETTER FIT LATEST OBSERVATIONS AND FORECAST TRENDS. ALL
PRODUCTS UPDATED AND OUT.
&&
.MARINE...STARTED SCA A BIT EARLIER AS WINDS ON RUC AND NEW NAM WERE
GOING HIGHER EARLIER. NORTHWEST WINDS CLEARED OUT THE SEA FOG SO
THAT ADVISORY HAS BEEN CANCELLED EARLIER. KEPT END TIMING OF SCA THE
SAME FOR NOW...BUT WILL LOOK AT ANY ADJUSTMENTS FOR THE AFTERNOON
PACKAGE. PUT LOW CHANCE POPS IN FOR THE AFTERNOON PACKAGE. THAT IS
IT FOR NOW.
&&
.PREV DISCUSSION... /ISSUED 553 AM CDT SUN MAR 16 2014/
DISCUSSION...HAVE ADJUSTED POP/WEATHER FORECAST FOR TODAY BASED
ON CURRENT RADAR TRENDS. CHANCE POPS ACROSS THE AREA WITH SLIGHT
CHANCE THUNDERSTORMS. CONVECTION IS DEVELOPING ALONG CAPE GRADIENT
WITH INITIAL BOUNDARY. CAPE VALUES RATHER LOW...BELOW 1000
J/KG...BUT SFC-6 KM BULK SHEAR VALUES AROUND 60KT. MESO MODELS NOT
HANDLING THE SITUATION WELL AT ALL. THINKING THOUGH IS THAT AS THE
UPPER JET SAGS SOUTH THE CONVECTION SHOULD WEAKEN A BIT...BUT WILL
LIKELY SEE AT LEAST SHOWER ACTIVITY PROGRESS EASTWARD ACROSS THE
FORECAST AREA THROUGH THE MORNING.
ALSO SEE 12Z AVIATION DISCUSSION BELOW.
AVIATION...WILL ADD CONVECTION INTO ALL TAFS WITH 12Z UPDATE THIS
MORNING. LRD SHOULD ONLY SEE CONVECTION POTENTIAL FOR THE NEXT
COUPLE OF HOURS...BUT ALL OTHER SITES COULD SEE AT LEAST SHOWERS
AND SOME THUNDERSTORM POTENTIAL THROUGH THE MORNING. OTHERWISE
SEEMS REMAIN ON TRACK WITH COLD FRONT MOVING THROUGH DURING THE
MORNING HOURS. EXPECTED STRONG NORTHERLY WINDS TO DEVELOP FOR ALL
SITES AND GRADUALLY WEAKEN TONIGHT. EXPECT MVFR TO IFR CIGE PRE
FRONT...AND VFR POST FRONT.
PREV DISCUSSION... /ISSUED 411 AM CDT SUN MAR 16 2014/
SHORT TERM (TODAY THROUGH MONDAY)...DIFFICULT FORECAST FOR THE
FIRST 18 HOURS OR SO OF THE FORECAST PERIOD. INITIALLY...HAVE FOG
SPREAD ACROSS MUCH OF SOUTH TEXAS...BUT MOSTLY A LIGHT FOG
SITUATION. SOME PATCHY...BRIEF DENSE FOG ON THE ISLANDS.
ADDITIONALLY...SEEING SOME VIRGA...OR MAYBE SPRINKLES DEVELOPING
AHEAD OF THE FRONT...WITH A FEW SHOWERS AND A COUPLE OF
THUNDERSTORMS NORTHWEST OF THE FORECAST AREA WITH INITIAL WIND
SHIFT/LEADING TROUGH. COULD BE A WEAK COLD FRONT ACROSS FROM DEL
RIO TO AUSTIN...BUT MAIN FRONT WITH COLDER/DRIER AIR IS STILL BACK
AROUND MIDLAND TO WICHITA FALLS. SURFACE THETA E FORECAST WOULD
INDICATE THE STRONGER FRONT ACCELERATING FASTER TOWARD SOUTH TEXAS
THIS MORNING...MAYBE CATCHING THE WEAKER FRONT BY THE COAST.
THAT SAID...STILL LOOK FOR A WIND SHIFT BEGINNING NORTHWEST ZONES
BY 11-12Z...BUT SURGE OF STRONGER WINDS/COOLER TEMPS WONT BE UNTIL
MID MORNING WEST. SHOULD SEE FRONTAL PASSAGE THROUGH TO THE COAST
BY 18Z. HAVE A CHANCE OF SHOWERS ACROSS THE AREA THROUGH THE
MORNING WITH A SLIGHT CHANCE OF THUNDERSTORMS EAST...BUT MAY NEED
TO EXPAND THUNDER POTENTIAL WEST IF CURRENT RADAR TRENDS CONTINUE.
LEFT EXIT REGION OF UPPER JET CERTAINLY HELPING IN CONVECTION
DEVELOPMENT THIS MORNING. THE JET DOES GRADUALLY SINK SOUTH
THROUGH THE MORNING AND SHOULD TAKE THUNDER POTENTIAL WITH IT.
HRRR MODEL DOING A VERY POOR JOB THIS MORNING WITH INITIALIZING
PRECIP...NOT INDICATING CONVECTION BETWEEN DEL RIO AND LAREDO AT
ALL.
ALL OF THE ABOVE LEADS TO A TRICKY TEMPERATURE AND WIND FORECAST
FOR TODAY. FIRST...WIND. PRECIOUS MODEL RUNS HAD ALL BEEN PROGGING
A VERY STRONG BURST OF WINDS AT 925MB IN WESTERN ZONES FOR
TODAY...00Z AND 06Z RUNS HAVE BACKED OFF SIGNIFICANTLY ON
THIS...AND WHAT STRONGER WINDS THEY DO HAVE LEFT ARE FARTHER WEST
OVER EASTERN MEXICO. THIS BRINGS INTO QUESTION WHETHER WEB COUNTY
CAN REALIZE THE WINDS FOR THE WIND ADVISORY CURRENTLY IN EFFECT.
THINKING ON THAT...THERE IS STILL A CHANCE FOR AREAS NEAR THE RIO
GRANDE TO REACH ADVISORY CRITERIA BRIEFLY...SO WILL LET THE
ADVISORY RIDE FOR NOW. WHILE WINDY CONDITIONS ARE EXPECTED...MOST
OF WEBB COUNTY...AS WELL AS THE REST OF THE FORECAST AREA WILL
LIKELY NOT BE GUSTING TO 40 MPH. TRICKY TEMPERATURE FORECAST TODAY
TOO...BUT THINK MOST AREAS WILL BE IN THE UPPER 60S AND LOWER 70S.
WITH COOLER HIGHS...HAVE CANCELLED RED FLAG WATCH FOR THE
AREA...THINKING CONDITIONS WILL NOT BE DRY ENOUGH FOR A CRITICAL
FIRE DANGER.
THE REST OF THE SHORT TERM FORECAST IS PRETTY BENIGN. PRECIP
IF IT LINGERS INTO THE EVENING SHOULD END PRETTY EARLY. WILL
REMAIN CLOUDY TONIGHT WITH UPPER LOW STILL OVER THE AREA...BUT
SHOULD SEE TEMPS INTO THE 40S FOR MOST OF US.
LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...DRY AND COOL MON NIGHT
UNDER CLEAR SKIES. THE LOW LEVEL RIDGE AXIS DOES SHIFT EAST MON EVE
AND A WEAK SOUTHERLY FLOW DEVELOPS LATE MON NIGHT...THEN STRENGTHENS
TUE. SUNNY AND DRY TUE....WARM AWAY FROM THE IMMEDIATE COAST GIVEN
THE SOUTH TO SOUTHWEST FLOW...WITH HIGHS IN THE MID TO UPPER 80S
INLAND...POSSIBLY NEAR 90 POSSIBLE ACROSS SOME AREAS OF BRUSH
COUNTRY AND RIO GRANDE. THERMAL GRADIENT BETWEEN COOL SHELF WATERS
AND INLAND TEMPS ON TUE WILL LEAD TO BREEZY TO WINDY CONDITIONS
ACROSS THE SOUTHERN COASTAL BEND AND POSSIBLE ELEVATED FIRE WEATHER
CONDITIONS...AS MOISTURE RETURN IS RATHER LIMITED. THE TAIL END OF A
WEAK COLD FRONT MAY SLIP INTO THE AREA ON WEDNESDAY AND STALL...
FOLLOWED CLOSER TO A GFS ENSEMBLE MEAN SOLUTION. UPPER LEVEL PATTERN
NOT COMPLETELY FAVORABLE TO DRIVE FRONT THROUGH THE AREA.
NEVERTHELESS...LOW LEVEL FLOW BACKED MORE EASTERLY WED AND THU WILL
RESULT IN SLIGHTLY COOLER TEMPS. MOISTURE RETURN AHEAD OF THE FRONT
CONTINUES TO APPEAR RATHER LIMITED...SO NO MENTION OF PRECIP
MENTIONED AT THIS TIME WED OR THU. ONSHORE FLOW AND MOISTURE DEPTH
DOES INCREASE FRI ACROSS COASTAL BEND AND SAT ACROSS MUCH OF THE
CWA...WITH PWATS INCREASING TO AROUND 1.4-1.5 INCHES. HOWEVER
FORCING IS RATHER LIMITED THIS FAR SOUTH SO AT THIS TIME HAVE CHOSE
NOT TO MENTION PRECIP IN THE OFFICIAL FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 72 45 65 44 85 / 40 10 10 0 0
VICTORIA 67 41 63 41 82 / 40 10 10 0 0
LAREDO 70 45 71 49 90 / 40 10 0 0 0
ALICE 71 44 67 41 89 / 40 10 0 0 0
ROCKPORT 67 46 62 49 75 / 40 10 10 0 0
COTULLA 68 41 70 42 86 / 40 10 0 0 0
KINGSVILLE 73 45 67 40 87 / 40 10 10 0 0
NAVY CORPUS 69 46 64 51 78 / 40 10 10 0 0
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 10 AM CDT MONDAY FOR THE FOLLOWING
ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY TO PORT ARANSAS...
BAYS AND WATERWAYS FROM PORT ARANSAS TO PORT O`CONNOR...
COASTAL WATERS FROM BAFFIN BAY TO PORT ARANSAS OUT 20 NM...
COASTAL WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL
OUT 20 NM...WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20
TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP
CHANNEL FROM 20 TO 60 NM.
&&
$$
GW/86...SHORT TERM
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
645 AM CDT SUN MAR 16 2014
.UPDATE...
A LINE OF NORTH-NORTHWESTERN CWA SHOWERS AND THUNDERSTORMS HAS
FORMED ALONG THE PRE-FRONTAL TROUGH LEADING THE MAIN COLD FRONTAL
BOUNDARY CURRENTLY COMING ACROSS THE I-35 CORRIDOR. THIS LINE IS
ADVANCING SLOWLY EAST-SOUTHEAST INTO A MORE HUMID AND LESS-CAPPED
(OR MORE UNSTABLE) AIR MASS AND WILL BE IMPACTING THE GREATER
HOUSTON METRO AREA WITHIN THE NEXT HOUR. THE MAIN IMPACTS FROM
THIS ACTIVITY WILL BE SMALL HAIL...WINDS IN EXCESS OF 30 MPH...AND
OCCASIONAL LIGHTNING. STRONGER CELLS....OR MORE WEST-TO-EAST
OREINTATED RAIN...COULD PRODUCE OVER A HALF OF AN INCH IN RAINFALL
ACCUMULATION...ALONG WITH GUSTY WINDS TO 40 MPH AND HAIL TO DIME
SIZE. W/V IMAGERY SHOWS A SHORTWAVE DISTURBANCE BETWEEN DEL RIO
AND LAREDO IN THE RIO GRANDE VALLEY THAT MAY BE HEADING UP IN THE
SOUTHWESTERLY FLOW. ALL OF THE ABOVE ELEMENTS INCREASING CONFIDENCE
OF RAISING MORNING INTO AFTERNOON SOUTHERN CWA POPS TO HIGH CHANCE
OR LIKELY. 31
&&
.PREV DISCUSSION... /ISSUED 607 AM CDT SUN MAR 16 2014/
AVIATION...
LINE OF RAIN WITH EMBEDDED SHOWERS AND THUNDERSTORMS WILL WORK ITS
WAY ACROSS SOUTHEAST TEXAS THIS MORNING. 12Z TAFS WILL HAVE RAINS IN
THEIR FORECAST FOR THIS ACTIVITY...AND WILL SHOW WINDS SHIFTING TO
THE NORTHWEST AND BECOMING GUSTY AS A STRONG COLD FRONT MOVES THROUGH
THE AREA. EXPECTING CEILINGS TO LIFT AS THE DAY PROGRESSES...INLAND
WELL UP NORTH THIS MORNING AND ALONG THE COAST THIS AFTERNOON. VFR
TOMORROW WITH SKIES CLEARING AS THE DAY PROGRESSES. 42
PREV DISCUSSION... /ISSUED 313 AM CDT SUN MAR 16 2014/
DISCUSSION...
CONVECTIVE ACTIVITY JUST AHEAD OF THE MAIN COLD FRONT BLOSSOMING
OVER SOUTHERN FORT WORTH`S CWA EARLY THIS MORNING. BELIEVE THESE
SHOWERS AND STORMS WILL MAINTAIN THEIR INTEGRITY AND REACH OUR
FAR NORTHERN ZONES IN THE NEXT HOUR OR SO. HRRR AND NAM12
REDEVELOPING DOWNSTREAM PRECIPITATION AS THE COLD FRONT MAKES ITS
WAY ACROSS OUR FORECAST AREA THROUGH THE DAY. ALTHOUGH PROG
SOUNDINGS AGREE WITH THE 00Z KCRP RAOB OF A DRY 5-85H LAYER...SE
TX FALLS UNDER A LEFT EXIT QUAD OF A NEAR-PARALLEL EXITING 25H
JET. MID TO UPPER 60 DEW POINT AIR INDICATES THERE IS ENOUGH LOWER
LAYER MOISTURE TO COUNTER THESE DRY MID-LAYERS...AND WITH THE
LIFT OF THE FRONT AND THE BETTER UPPER DYNAMICS...LEFT HIGH END
CHANCE MORNING POPS OVER OUR CENTRAL AND SOUTHERN FORECAST AREA.
THE VICINITY OF THE UPPER LOW WITH...EITHER A SURFACE LOW RIDING
UP ALONG THE FRONTAL BOUNDARY OR A WEAK SHORTWAVE DISTURBANCE
EMBEDDED WITHIN THE SW`ERLY FLOW...ONLY STRENGTHENS THE ARGUMENT
FOR KEEPING HIGHER POPS IN PLACE THROUGH AT LEAST MID-DAY. GENERALLY
.MOST LOCALES WILL PICK UP A QUARTER OF AN INCH OR LESS ALTHOUGH
LOCALIZED SPOTS COULD QUICKLY PICK UP A HALF AN INCH OR MORE FROM
STRONGER CELLS. AMPED UP NORTHERLIES IN THE FRONT`S WAKE WILL NEAR
ADVISORY LEVELS THIS AFTERNOON... ESPECIALLY ALONG THE COAST. WILL
HOLD OFF ON THE WIND ADVISORY AND HAND OFF TO THE NEXT SHIFT AS
THEY WILL HAVE A BETTER HANDLE ON THE `WHEN AND WHERE` OF
SUSTAINED 25 MPH WINDS.
5H TROUGH AXIS TO THE EAST OF REGION MONDAY MORNING WITH STRONG CAA
COOLING CONDITIONS DOWN INTO THE MIDDLE 30S TO LOWER 4OS INLAND...MID
40S AT COAST....WITH A BRISK NORTH WIND. MODERATE OFFSHORE FLOW WILL
SLOWLY WEAKEN THROUGH MONDAY`S EVENING HOURS AS THE REGION FALLS
BETWEEN TWO FRONTAL BOUNDARIES. A CLEARING AND COOL MONDAY AFTERNOON
WILL LEAD TO A RELATIVELY WARMER...ALBEIT CHILLY...TUESDAY MORNING
IN THE MEAN LOW-MID 40S. RETURN FLOW BY TUESDAY SUNRISE...WITH PLENTY
OF AFTERNOON SUN IN ALLOWING MANY COMMUNITIES TO WARM UP INTO THE
MIDDLE TO UPPER 70S. A WEAK BOUNDARY WILL APPROACH EASTERN TEXAS
LATE TUESDAY OR EARLY WEDNESDAY AND WASH OUT OVER THE FA...KEEPING
WINDS LIGHT AND VARIABLE BUT ALSO PULLING DOWN A COOLER AIR MASS
AND REGULATING MID-WEEK WARMTH TO THE SEASONABLE AVERAGE LOWER
70S. A COUPLE OF DRY AND COMFORTABLE DAYS TEMPERATURE/MOISTURE-
WISE WEDNESDAY THROUGH FRIDAY AS TEXAS FALLS UNDER A NEAR-ZONAL
SYNOPTIC FLOW PATTERN. THE EVOLUTION OF GRADUAL WESTERN CONUS
TROUGHING WILL ALLOW A SERIES OF WEAK W-SW DISTURBANCES TO RIDE
ON IN AND INCREASE LATE WEEK AND WEEKEND RAIN CHANCES. 31
MARINE...
LIGHT TO MODERATE ONSHORE WINDS AND POSSIBLE AREAS OF DENSE SEA
FOG SHOULD PERSIST UNTIL A STRONG COLD FRONT MOVES THROUGH THE
COASTAL WATERS EARLY THIS AFTERNOON. IN THE WAKE OF THE FRONT...
EXPECT STRONG NORTHWEST WINDS AND INCREASING SEAS TO DEVELOP.
SMALL CRAFT ADVISORIES WILL BE NEEDED...AND SOME GALE FORCE WIND
GUSTS WILL BE POSSIBLE. EXPECT WINDS AND SEAS TO GRADUALLY DECREASE
DURING THE DAY ON MONDAY. BY TUESDAY...SOUTH TO SOUTHWEST WINDS
WILL RETURN TO THE AREA. LIGHT TO MODERATE ONSHORE WINDS ARE
ANTICIPATED FOR THE REMAINDER OF THE WEEK. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 61 36 60 42 77 / 20 10 10 0 0
HOUSTON (IAH) 67 40 60 45 78 / 50 10 10 0 0
GALVESTON (GLS) 67 44 59 51 70 / 60 10 10 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 AM CDT MONDAY FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...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...31
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
607 AM CDT SUN MAR 16 2014
.AVIATION...
LINE OF RAIN WITH EMBEDDED SHOWERS AND THUNDERSTORMS WILL WORK ITS
WAY ACROSS SOUTHEAST TEXAS THIS MORNING. 12Z TAFS WILL HAVE RAINS IN
THEIR FORECAST FOR THIS ACTIVITY...AND WILL SHOW WINDS SHIFTING TO
THE NORTHWEST AND BECOMING GUSTY AS A STRONG COLD FRONT MOVES THROUGH
THE AREA. EXPECTING CEILINGS TO LIFT AS THE DAY PROGRESSES...INLAND
WELL UP NORTH THIS MORNING AND ALONG THE COAST THIS AFTERNOON. VFR
TOMORROW WITH SKIES CLEARING AS THE DAY PROGRESSES. 42
&&
.PREV DISCUSSION... /ISSUED 313 AM CDT SUN MAR 16 2014/
DISCUSSION...
CONVECTIVE ACTIVITY JUST AHEAD OF THE MAIN COLD FRONT BLOSSOMING
OVER SOUTHERN FORT WORTH`S CWA EARLY THIS MORNING. BELIEVE THESE
SHOWERS AND STORMS WILL MAINTAIN THEIR INTEGRITY AND REACH OUR
FAR NORTHERN ZONES IN THE NEXT HOUR OR SO. HRRR AND NAM12
REDEVELOPING DOWNSTREAM PRECIPITATION AS THE COLD FRONT MAKES ITS
WAY ACROSS OUR FORECAST AREA THROUGH THE DAY. ALTHOUGH PROG
SOUNDINGS AGREE WITH THE 00Z KCRP RAOB OF A DRY 5-85H LAYER...SE
TX FALLS UNDER A LEFT EXIT QUAD OF A NEAR-PARALLEL EXITING 25H
JET. MID TO UPPER 60 DEW POINT AIR INDICATES THERE IS ENOUGH LOWER
LAYER MOISTURE TO COUNTER THESE DRY MID-LAYERS...AND WITH THE
LIFT OF THE FRONT AND THE BETTER UPPER DYNAMICS...LEFT HIGH END
CHANCE MORNING POPS OVER OUR CENTRAL AND SOUTHERN FORECAST AREA.
THE VICINITY OF THE UPPER LOW WITH...EITHER A SURFACE LOW RIDING
UP ALONG THE FRONTAL BOUNDARY OR A WEAK SHORTWAVE DISTURBANCE
EMBEDDED WITHIN THE SW`ERLY FLOW...ONLY STRENGTHENS THE ARGUMENT
FOR KEEPING HIGHER POPS IN PLACE THROUGH AT LEAST MID-DAY. GENERALLY
..MOST LOCALES WILL PICK UP A QUARTER OF AN INCH OR LESS ALTHOUGH
LOCALIZED SPOTS COULD QUICKLY PICK UP A HALF AN INCH OR MORE FROM
STRONGER CELLS. AMPED UP NORTHERLIES IN THE FRONT`S WAKE WILL NEAR
ADVISORY LEVELS THIS AFTERNOON... ESPECIALLY ALONG THE COAST. WILL
HOLD OFF ON THE WIND ADVISORY AND HAND OFF TO THE NEXT SHIFT AS
THEY WILL HAVE A BETTER HANDLE ON THE `WHEN AND WHERE` OF
SUSTAINED 25 MPH WINDS.
5H TROUGH AXIS TO THE EAST OF REGION MONDAY MORNING WITH STRONG CAA
COOLING CONDITIONS DOWN INTO THE MIDDLE 30S TO LOWER 4OS INLAND...MID
40S AT COAST....WITH A BRISK NORTH WIND. MODERATE OFFSHORE FLOW WILL
SLOWLY WEAKEN THROUGH MONDAY`S EVENING HOURS AS THE REGION FALLS
BETWEEN TWO FRONTAL BOUNDARIES. A CLEARING AND COOL MONDAY AFTERNOON
WILL LEAD TO A RELATIVELY WARMER...ALBEIT CHILLY...TUESDAY MORNING
IN THE MEAN LOW-MID 40S. RETURN FLOW BY TUESDAY SUNRISE...WITH PLENTY
OF AFTERNOON SUN IN ALLOWING MANY COMMUNITIES TO WARM UP INTO THE
MIDDLE TO UPPER 70S. A WEAK BOUNDARY WILL APPROACH EASTERN TEXAS
LATE TUESDAY OR EARLY WEDNESDAY AND WASH OUT OVER THE FA...KEEPING
WINDS LIGHT AND VARIABLE BUT ALSO PULLING DOWN A COOLER AIR MASS
AND REGULATING MID-WEEK WARMTH TO THE SEASONABLE AVERAGE LOWER
70S. A COUPLE OF DRY AND COMFORTABLE DAYS TEMPERATURE/MOISTURE-
WISE WEDNESDAY THROUGH FRIDAY AS TEXAS FALLS UNDER A NEAR-ZONAL
SYNOPTIC FLOW PATTERN. THE EVOLUTION OF GRADUAL WESTERN CONUS
TROUGHING WILL ALLOW A SERIES OF WEAK W-SW DISTURBANCES TO RIDE
ON IN AND INCREASE LATE WEEK AND WEEKEND RAIN CHANCES. 31
MARINE...
LIGHT TO MODERATE ONSHORE WINDS AND POSSIBLE AREAS OF DENSE SEA
FOG SHOULD PERSIST UNTIL A STRONG COLD FRONT MOVES THROUGH THE
COASTAL WATERS EARLY THIS AFTERNOON. IN THE WAKE OF THE FRONT...
EXPECT STRONG NORTHWEST WINDS AND INCREASING SEAS TO DEVELOP.
SMALL CRAFT ADVISORIES WILL BE NEEDED...AND SOME GALE FORCE WIND
GUSTS WILL BE POSSIBLE. EXPECT WINDS AND SEAS TO GRADUALLY DECREASE
DURING THE DAY ON MONDAY. BY TUESDAY...SOUTH TO SOUTHWEST WINDS
WILL RETURN TO THE AREA. LIGHT TO MODERATE ONSHORE WINDS ARE
ANTICIPATED FOR THE REMAINDER OF THE WEEK. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 61 36 60 42 77 / 20 10 10 0 0
HOUSTON (IAH) 67 40 60 45 78 / 50 10 10 0 0
GALVESTON (GLS) 67 44 59 51 70 / 50 10 10 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 AM CDT MONDAY FOR THE
FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...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...31
AVIATION/MARINE...42
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
313 AM CDT SUN MAR 16 2014
.DISCUSSION...
CONVECTIVE ACTIVITY JUST AHEAD OF THE MAIN COLD FRONT BLOSSOMING
OVER SOUTHERN FORT WORTH`S CWA EARLY THIS MORNING. BELIEVE THESE
SHOWERS AND STORMS WILL MAINTAIN THEIR INTEGRITY AND REACH OUR
FAR NORTHERN ZONES IN THE NEXT HOUR OR SO. HRRR AND NAM12
REDEVELOPING DOWNSTREAM PRECIPITATION AS THE COLD FRONT MAKES ITS
WAY ACROSS OUR FORECAST AREA THROUGH THE DAY. ALTHOUGH PROG
SOUNDINGS AGREE WITH THE 00Z KCRP RAOB OF A DRY 5-85H LAYER...SE
TX FALLS UNDER A LEFT EXIT QUAD OF A NEAR-PARALLEL EXITING 25H
JET. MID TO UPPER 60 DEW POINT AIR INDICATES THERE IS ENOUGH LOWER
LAYER MOISTURE TO COUNTER THESE DRY MID-LAYERS...AND WITH THE
LIFT OF THE FRONT AND THE BETTER UPPER DYNAMICS...LEFT HIGH END
CHANCE MORNING POPS OVER OUR CENTRAL AND SOUTHERN FORECAST AREA.
THE VICINITY OF THE UPPER LOW WITH...EITHER A SURFACE LOW RIDING
UP ALONG THE FRONTAL BOUNDARY OR A WEAK SHORTWAVE DISTURBANCE
EMBEDDED WITHIN THE SW`ERLY FLOW...ONLY STRENGTHENS THE ARGUMENT
FOR KEEPING HIGHER POPS IN PLACE THROUGH AT LEAST MID-DAY. GENERALLY
...MOST LOCALES WILL PICK UP A QUARTER OF AN INCH OR LESS ALTHOUGH
LOCALIZED SPOTS COULD QUICKLY PICK UP A HALF AN INCH OR MORE FROM
STRONGER CELLS. AMPED UP NORTHERLIES IN THE FRONT`S WAKE WILL NEAR
ADVISORY LEVELS THIS AFTERNOON... ESPECIALLY ALONG THE COAST. WILL
HOLD OFF ON THE WIND ADVISORY AND HAND OFF TO THE NEXT SHIFT AS
THEY WILL HAVE A BETTER HANDLE ON THE `WHEN AND WHERE` OF
SUSTAINED 25 MPH WINDS.
5H TROUGH AXIS TO THE EAST OF REGION MONDAY MORNING WITH STRONG CAA
COOLING CONDITIONS DOWN INTO THE MIDDLE 30S TO LOWER 4OS INLAND...MID
40S AT COAST....WITH A BRISK NORTH WIND. MODERATE OFFSHORE FLOW WILL
SLOWLY WEAKEN THROUGH MONDAY`S EVENING HOURS AS THE REGION FALLS
BETWEEN TWO FRONTAL BOUNDARIES. A CLEARING AND COOL MONDAY AFTERNOON
WILL LEAD TO A RELATIVELY WARMER...ALBEIT CHILLY...TUESDAY MORNING
IN THE MEAN LOW-MID 40S. RETURN FLOW BY TUESDAY SUNRISE...WITH PLENTY
OF AFTERNOON SUN IN ALLOWING MANY COMMUNITIES TO WARM UP INTO THE
MIDDLE TO UPPER 70S. A WEAK BOUNDARY WILL APPROACH EASTERN TEXAS
LATE TUESDAY OR EARLY WEDNESDAY AND WASH OUT OVER THE FA...KEEPING
WINDS LIGHT AND VARIABLE BUT ALSO PULLING DOWN A COOLER AIR MASS
AND REGULATING MID-WEEK WARMTH TO THE SEASONABLE AVERAGE LOWER
70S. A COUPLE OF DRY AND COMFORTABLE DAYS TEMPERATURE/MOISTURE-
WISE WEDNESDAY THROUGH FRIDAY AS TEXAS FALLS UNDER A NEAR-ZONAL
SYNOPTIC FLOW PATTERN. THE EVOLUTION OF GRADUAL WESTERN CONUS
TROUGHING WILL ALLOW A SERIES OF WEAK W-SW DISTURBANCES TO RIDE
ON IN AND INCREASE LATE WEEK AND WEEKEND RAIN CHANCES. 31
&&
.MARINE...
LIGHT TO MODERATE ONSHORE WINDS AND POSSIBLE AREAS OF DENSE SEA
FOG SHOULD PERSIST UNTIL A STRONG COLD FRONT MOVES THROUGH THE
COASTAL WATERS EARLY THIS AFTERNOON. IN THE WAKE OF THE FRONT...
EXPECT STRONG NORTHWEST WINDS AND INCREASING SEAS TO DEVELOP.
SMALL CRAFT ADVISORIES WILL BE NEEDED...AND SOME GALE FORCE WIND
GUSTS WILL BE POSSIBLE. EXPECT WINDS AND SEAS TO GRADUALLY DECREASE
DURING THE DAY ON MONDAY. BY TUESDAY...SOUTH TO SOUTHWEST WINDS
WILL RETURN TO THE AREA. LIGHT TO MODERATE ONSHORE WINDS ARE
ANTICIPATED FOR THE REMAINDER OF THE WEEK. 42
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 61 36 60 42 77 / 20 10 10 0 0
HOUSTON (IAH) 67 40 60 45 78 / 50 10 10 0 0
GALVESTON (GLS) 67 44 59 51 70 / 50 10 10 0 0
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...DENSE FOG ADVISORY UNTIL 7 AM CDT THIS MORNING FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...31/42
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1154 PM EDT MON MAR 17 2014
.SYNOPSIS...
A WEDGE OF HIGH PRESSURE IS EXPECTED TO RESIDE OVER THE AREA THROUGH
WEDNESDAY...WHILE THE SOUTHEAST LOW MOVES OFF THE COAST TONIGHT INTO
WEDNESDAY. A COLD FRONT THROUGH THE AREA LATE WEDNESDAY AFTERNOON
INTO WEDNESDAY NIGHT.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 1150 PM EDT MONDAY...
CONCERNS FOR ICING CONTINUE TO GROW ACROSS THE EASTERN NC PIEDMONT
COUNTIES AS MOISTURE FROM SE DEVELOPING COASTAL SYSTEM BACKS NWWD
INTO THIS REGION. ICING ACCUMULATIONS ON THE VERGE OF WARNING
CRITERIA AND IT HAS BEEN VERY TROUBLESOME. SEVERAL LOCATIONS IN
ROCKINGHAM AND CASWELL COUNTIES WITH ICE ACCUMULATIONS NEAR 1/4
INCH...BUT MOST AREAS JUST BELOW THIS. PER EARLIER HRRR...FEEL
THAT BULK OF THIS PCPN WILL END WITHIN THE NEXT TWO TO THREE HOURS...SO
A WARNING AT THIS POINT WOULD PROBABLY ADD LITTLE VALUE. SO WILL
STAY COURSE WITH STRONGLY WORDED ADVISORY WITH ACCUMULATIONS NEAR
1/4 INCH IN SOME AREAS. ELSEWHERE...FZDZ AND FZFG COVER THE
SITUATION WITH NO CHANGES NEEDED AT THIS TIME. HAVE HAD TO LOWER
TEMPERATURES A FEW DEGREES AGAIN THROUGHOUT THE NIGHT AS THIS
WEDGE IS HOLDING TOUGH.
AS OF 745 PM EDT MONDAY...
MULTIPLE WINTER WEATHER CONCERNS CONTINUE THIS EVENING.
FIRST...SOUTHEAST U.S. COASTAL SYSTEM RESULTING IN RETROGRADING
PRECIPITATION BACK INTO THE NC/SOUTHSIDE VA COUNTIES. HRRR MODEL
SEEMS TO HAVE THE BEST HANDLE ON THIS AS THE WRF DID NOT HAVE A
CLUE AND THE LARGER SYNOPTIC SCALE MODELS HANDLE IT POORLY. USING
THE HRRR AS A GUIDE...HAVE INCREASED POPS TO LIKELY INTO OUR NC
COUNTIES AND TOWARD MTV/DAN THROUGH 06Z...THEN TAPER BACK TO
LOW/MID CHC RANGE AFTER THAT. THE BIG CONCERN WITH THIS AREA OF
PCPN IS THE TEMPERATURE. CLASSIC...SIGNIFICANT WEDGE REMAINS IN
PLACE AND IS NOT GOING ANYWHERE...POSSIBLY UNTIL WED AFTERNOON.
WRF HAD US IN THE MID 40S THIS AFTERNOON...WHERE IN REALITY IT HAS
NOT BUDGED OUT OF THE MID 20S IN MANY AREAS. THE ENTIRE CWA IS
BELOW FREEZING AT THIS POINT AND WILL REMAIN SO UNTIL AT LEAST
MID-DAY TUE. THUS...ANY PCPN WILL BE FZRA OR IP. WARM NOSE TOO
DEEP AND DYNAMICS TOO WEAK FOR ANY SN. FOR WSW...HAVE SEPARATED
OUT SOUTHERN COUNTIES WHERE FZRA/IP MORE LIKELY FROM COUNTIES
FURTHER NORTH WHERE PCPN WILL LIKELY BE JUST FZDZ/FZFG. IN THE
WEST...COOP OBSERVER RECENTLY CALLED IN FROM WYTHE COUNTY
REPORTING SIGNIFICANT RIME ICING FROM FZFG AND NOTED THAT PREVIOUSLY
DRY SFCS WERE COATED WITH ICE. HAVE ISSUED A FZFG ADVISORY FOR ALL
WESTERN COUNTIES NOT INCLUDED IN THE WSW. HAVE ENDED THAT AT 14Z
SINCE THESE ARE THE AREAS MORE LIKELY TO CREEP ABOVE 32F SOONER ON
THE WEST SIDE OF THE WEDGE.
AS OF 410 PM EDT MONDAY...
WINTER WEATHER ADVISORIES HAVE BEEN POSTED FOR THIS EVENING UNTIL
NOON WEDNESDAY FOR AREAS OF FREEZING RAIN AND FREEZING DRIZZLE
FOR MOST OF SOUTHWEST VIRGINIA AND NORTHWEST NORTH CAROLINA.
SFC HIGH CENTERED NEAR OTTAWA WITH A SFC RIDGE EXTENDING DOWN THE
LEE OF THE APPALACHIANS TO THE CAROLINA PIEDMONT. THIS STRONG
WEDGE/COLD AIR DAMMING WILL PERSIST THIS EVENING INTO TUESDAY. MID
AND HIGH LEVEL MOISTURE SHOULD LEAVE BY LATE AFTERNOON INTO THIS
EVENING LEAVING NO POTENTIAL FOR SNOW CRYSTALS IN THE CLOUDS. THERE
IS A SMALL WINDOW FOR A BRIEF PERIOD OF SNOW AND SLEET MAINLY ACROSS
SOUTHERN PORTIONS OF CWA THIS EVENING INTO TONIGHT. EXPECT LIGHT
FREEZING RAIN AND FREEZING DRIZZLE TO BE MAIN PTYPE TONIGHT INTO
TUESDAY. AREAS OF FOG WILL DEVELOP ALONG THE BLUE RIDGE
OVERNIGHT. IN GENERAL...ANY ICE WILL BE A TENTH OF AN INCH OR
LESS. PRECIPITATION AMOUNTS WILL BE LIGHT. THERE IS THE POTENTIAL
FOR BLACK ICE OVERNIGHT INTO WEDNESDAY. LOW TEMPERATURES TONIGHT
WILL RANGE FROM AROUND 20 DEGREES IN THE NORTHWEST MOUNTAINS TO
THE LOWER 30S IN THE PIEDMONT. ANOTHER STRONG DISTURBANCE MOVING
OFF THE CAROLINA COAST TUESDAY WITH SURFACE HIGH STRENGTHENING
OVER NEW ENGLAND...WILL SERVE TO REINFORCE THE WEDGE AND THE EAST
TO NORTHEAST FLOW. INCREASED POPS TUESDAY MAINLY IN THE EASTERN
UPSLOPE AREA. HIGHS ON TUESDAY ARE TRICKY. PLAYED HIGHS FROM THE
LOWER 30S ALONG BLUE RIDGE TO NEAR 50 DEGREES IN THE FAR WEST.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
AS OF 400 PM EDT MONDAY...
WEDGE OF VERY COOL HIGH PRESSURE WILL LIKELY PERSIST OVER MOST...IF
NOT ALL OF THE BLACKSBURG FORECAST AREA INTO/THROUGH WEDNESDAY AS
UPPER RIDGE BUILDS OVER EASTERN AND SOUTHEASTERN PORTION OF THE
NATION DOWNSTREAM OF APPROACHING TROF ADVANCING EAST FROM THE
NORTHERN PLAINS.
ABUNDANT MOISTURE TRAPPED UNDER A STEEP INVERSION IN THE LOWER 6K FT
OF THE TROPOSPHERE WILL ENSURE THAT TEMPERATURES OVER THE ENTIRE
FORECAST AREA REMAIN WELL BELOW NORMAL THROUGH THIS PERIOD...AND
ALSO WELL BELOW GUIDANCE...ESPECIALLY DURING THE DAYTIME PERIODS.
EAST TO SOUTHEAST LOWER TROPOSPHERIC FLOW AROUND THE PERIPHERY OF
THE SURFACE RIDGE TO THE NORTHEAST...AND ADVANCING LOW PRESSURE TO
THE WEST WILL RESULT IN FORCED ASCENT THROUGH A SATURATED LOWER
LAYER TO WRING OUT SPOTTY VERY LIGHT RAIN OR FREEZING
RAIN/DRIZZLE...MAXIMIZED ALONG AND MAINLY EAST OF THE BLUE RIDGE.
WARM NOSE AT TOP OF INVERSION LAYER SUFFICIENTLY ABOVE
FREEZING...AND WITH NO MID/HIGH LEVEL CLOUDS TO SUPPORT SEEDER-
FEEDER PROCESSES THROUGH DENDRITIC LEVEL...PRECIPITATION THIS TIME
AROUND WILL BE ALL LIQUID AS OPPOSED TO SNOW/SLEET.
OVERALL AMOUNTS OF MEASURABLE PRECIPITATION TUESDAY NIGHT INTO
WEDNESDAY WILL BE MEAGER...PERHAPS ONLY A FEW HUNDREDTHS OF AN INCH
IN MOST LOCATIONS...BUT STILL ENOUGH TO RESULT IN SOME GLAZING OF
ELEVATED EXPOSED SURFACES...AGAIN MAXIMIZED ACROSS THE EASTERN
FLANKS OF THE APPALACHIANS. AS A RESULT...MAY AGAIN HAVE TO POST
ANOTHER WINTER WEATHER ADVISORY IN SOME LOCATIONS FOR TUESDAY NIGHT
INTO WEDNESDAY MORNING...BUT WILL HOLD OFF UNTIL CURRENT HEADLINES
IN NEAR-TERM PERIOD EXPIRE SO AS TO NOT CONFUSE THE ISSUE...AND
HIGHLIGHT IN HAZARDOUS WEATHER OUTLOOK FOR NOW.
TROF AND ASSOCIATED COOL FRONT FORECAST TO SWEEP EAST THROUGH THE
BLACKSBURG FORECAST AREA BY/DURING WEDNESDAY NIGHT...POSSIBLY
PRECEDED AND ACCOMPANIED BY SOME BRIEF SPOTTY SHOWERS...MAINLY
ACROSS THE WESTERN FLANKS OF THE APPALACHIANS WEDNESDAY
AFTERNOON...GRADUALLY TRANSITIONING TO SOME UPSLOPE RAIN/SNOW
SHOWERS AS COLDER AIR FINALLY ARRIVES LATER WEDNESDAY NIGHT.
REGARDLESS...ARRIVAL OF COLD FRONT WILL ACTUALLY HELP TO SCOUR OUT
TENACIOUS COOL WEDGE OVER AREA...SUCH THAT TEMPERATURES MAY ACTUALLY
SPIKE WITH ONSET OF MIXING BEFORE TRAILING OFF AGAIN LATER WEDNESDAY
NIGHT.
SURFACE HIGH PRESSURE BUILDING INTO THE AREA FROM THE WEST THURSDAY
INTO THURSDAY NIGHT WILL RESULT IN CLEARING SKIES AND A RETURN TO
TEMPERATURES CLOSER TO SEASONAL AVERAGES.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 400 PM EDT SUNDAY...
MAINLY DRY AND SEASONAL WEATHER EXPECTED IN THE FRIDAY/FRIDAY NIGHT
TIMEFRAME AS SURFACE RIDGE MOVES OVER AND THEN TO THE EAST OF THE
FORECAST AREA.
APPROACH OF YET ANOTHER WAVE IN THE NORTHERN STREAM IS THEN SET TO
PUSH EAST/SOUTHEAST THROUGH THE REGION ON SATURDAY...LIKELY
PRECEDED AND ACCOMPANIED BY SCATTERED SHOWERS.
BELOW NORMAL TEMPERATURES...BUT WITH A RETURN TO DRY WEATHER IS THEN
EXPECTED TO RETURN TO MOST AREAS IN THE SUNDAY/MONDAY
TIMEFRAME...WITH PERHAPS THE EXCEPTION OF THE WESTERN FLANKS OF THE
APPALACHIANS...WHERE SOME UPSLOPING CLOUDS...AND POSSIBLY EVEN SOME
SPOTTY RAIN/SNOW SHOWERS ARE POSSIBLE INTO EARLY NEXT WEEK.
&&
.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
AS OF 830 PM EDT MONDAY...
STRONG WEDGE OF COLD HIGH PRESSURE WILL REMAIN THE DOMINANT
WEATHER FEATURE FOR OUR REGION THROUGH THE TAF VALID PERIOD. THIS
WILL RESULT IN WIDESPREAD MVFR-IFR CIGS. A SOUTHEAST COASTAL
SYSTEM TRACKING TO OFF THE NC COAST BY TUE AFTERNOON WILL SIMPLY
REINFORCE THE WEDGE WITH INCREASING NE FLOW. THROUGH 06Z...AREAS
OF FZRA AND IP WILL IMPACT NORTHWEST NC INTO SOUTHSIDE
VA...INCLUDING DAN. THEREAFTER IN THESE AREAS...AS WELL AS
THROUGHOUT THE REMAINDER OF THE CWA...EXPECT AREAS OF FZDZ AND
FZFG OVERNIGHT WITH RIME ICING ON EXPOSED SURFACES AND WIDESPREAD
MVFR VSBYS. WINDS NE-ENE 7-10KTS
OVERNIGHT...INCREASING...ESPECIALLY EAST OF THE BLUE RIDGE AFTER
DAYBREAK TUE...TO 10-13KTS WITH GUSTS TO 20KTS ACROSS THE BLUE
RIDGE.
MEDIUM TO HIGH CONFIDENCE IN CIGS AND VSBYS THROUGH THE TAF VALID
PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND DIR/SPD THROUGH THE TAF VALID
PERIOD.
.EXTENDED AVIATION DISCUSSION...
VFR CONDITIONS ARE FINALLY EXPECTED TO RETURN WEDNESDAY AFTERNOON
AND CONTINUE THROUGH FRIDAY. GUSTY WEST WINDS ARE EXPECTED
WEDNESDAY AFTERNOON AND EVENING. SUB VFR CONDITIONS MAY RETURN FOR
THE WEEKEND AS A CANADIAN COLD FRONT MOVES THROUGH THE REGION
ACCOMPANIED BY SHOWERS...THEN UPSLOPE FLOW AND COLDER
TEMPERATURES.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY UNTIL NOON EDT TUESDAY FOR VAZ011-
013>020-022>024-032>035-043>047-058-059.
FREEZING FOG ADVISORY UNTIL 10 AM EDT TUESDAY FOR VAZ007-009-
010-012.
NC...WINTER WEATHER ADVISORY UNTIL NOON EDT TUESDAY FOR NCZ001>006-
018>020.
WV...FREEZING FOG ADVISORY UNTIL 10 AM EDT TUESDAY FOR WVZ042>045.
&&
$$
SYNOPSIS...KK
NEAR TERM...KK/RAB
SHORT TERM...WERT
LONG TERM...WERT
AVIATION...KK/RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
911 PM EDT MON MAR 17 2014
.SYNOPSIS...
A WEDGE OF HIGH PRESSURE IS EXPECTED TO RESIDE OVER THE AREA THROUGH
WEDNESDAY...WHILE THE SOUTHEAST LOW MOVES OFF THE COAST TONIGHT INTO
WEDNESDAY. A COLD FRONT THROUGH THE AREA LATE WEDNESDAY AFTERNOON
INTO WEDNESDAY NIGHT.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 745 PM EDT MONDAY...
MULTIPLE WINTER WEATHER CONCERNS CONTINUE THIS EVENING.
FIRST...SOUTHEAST U.S. COASTAL SYSTEM RESULTING IN RETROGRADING
PRECIPITATION BACK INTO THE NC/SOUTHSIDE VA COUNTIES. HRRR MODEL
SEEMS TO HAVE THE BEST HANDLE ON THIS AS THE WRF DID NOT HAVE A
CLUE AND THE LARGER SYNOPTIC SCALE MODELS HANDLE IT POORLY. USING
THE HRRR AS A GUIDE...HAVE INCREASED POPS TO LIKELY INTO OUR NC
COUNTIES AND TOWARD MTV/DAN THROUGH 06Z...THEN TAPER BACK TO
LOW/MID CHC RANGE AFTER THAT. THE BIG CONCERN WITH THIS AREA OF
PCPN IS THE TEMPERATURE. CLASSIC...SIGNIFICANT WEDGE REMAINS IN
PLACE AND IS NOT GOING ANYWHERE...POSSIBLY UNTIL WED AFTERNOON.
WRF HAD US IN THE MID 40S THIS AFTERNOON...WHERE IN REALITY IT HAS
NOT BUDGED OUT OF THE MID 20S IN MANY AREAS. THE ENTIRE CWA IS
BELOW FREEZING AT THIS POINT AND WILL REMAIN SO UNTIL AT LEAST
MID-DAY TUE. THUS...ANY PCPN WILL BE FZRA OR IP. WARM NOSE TOO
DEEP AND DYNAMICS TOO WEAK FOR ANY SN. FOR WSW...HAVE SEPARATED
OUT SOUTHERN COUNTIES WHERE FZRA/IP MORE LIKELY FROM COUNTIES
FURTHER NORTH WHERE PCPN WILL LIKELY BE JUST FZDZ/FZFG. IN THE
WEST...COOP OBSERVER RECENTLY CALLED IN FROM WYTHE COUNTY
REPORTING SIGNIFICANT RIME ICING FROM FZFG AND NOTED THAT PREVIOUSLY
DRY SFCS WERE COATED WITH ICE. HAVE ISSUED A FZFG ADVISORY FOR ALL
WESTERN COUNTIES NOT INCLUDED IN THE WSW. HAVE ENDED THAT AT 14Z
SINCE THESE ARE THE AREAS MORE LIKELY TO CREEP ABOVE 32F SOONER ON
THE WEST SIDE OF THE WEDGE.
AS OF 410 PM EDT MONDAY...
WINTER WEATHER ADVISORIES HAVE BEEN POSTED FOR THIS EVENING UNTIL
NOON WEDNESDAY FOR AREAS OF FREEZING RAIN AND FREEZING DRIZZLE
FOR MOST OF SOUTHWEST VIRGINIA AND NORTHWEST NORTH CAROLINA.
SFC HIGH CENTERED NEAR OTTAWA WITH A SFC RIDGE EXTENDING DOWN THE
LEE OF THE APPALACHIANS TO THE CAROLINA PIEDMONT. THIS STRONG
WEDGE/COLD AIR DAMMING WILL PERSIST THIS EVENING INTO TUESDAY. MID
AND HIGH LEVEL MOISTURE SHOULD LEAVE BY LATE AFTERNOON INTO THIS
EVENING LEAVING NO POTENTIAL FOR SNOW CRYSTALS IN THE CLOUDS. THERE
IS A SMALL WINDOW FOR A BRIEF PERIOD OF SNOW AND SLEET MAINLY ACROSS
SOUTHERN PORTIONS OF CWA THIS EVENING INTO TONIGHT. EXPECT LIGHT
FREEZING RAIN AND FREEZING DRIZZLE TO BE MAIN PTYPE TONIGHT INTO
TUESDAY. AREAS OF FOG WILL DEVELOP ALONG THE BLUE RIDGE
OVERNIGHT. IN GENERAL...ANY ICE WILL BE A TENTH OF AN INCH OR
LESS. PRECIPITATION AMOUNTS WILL BE LIGHT. THERE IS THE POTENTIAL
FOR BLACK ICE OVERNIGHT INTO WEDNESDAY. LOW TEMPERATURES TONIGHT
WILL RANGE FROM AROUND 20 DEGREES IN THE NORTHWEST MOUNTAINS TO
THE LOWER 30S IN THE PIEDMONT. ANOTHER STRONG DISTURBANCE MOVING
OFF THE CAROLINA COAST TUESDAY WITH SURFACE HIGH STRENGTHENING
OVER NEW ENGLAND...WILL SERVE TO REINFORCE THE WEDGE AND THE EAST
TO NORTHEAST FLOW. INCREASED POPS TUESDAY MAINLY IN THE EASTERN
UPSLOPE AREA. HIGHS ON TUESDAY ARE TRICKY. PLAYED HIGHS FROM THE
LOWER 30S ALONG BLUE RIDGE TO NEAR 50 DEGREES IN THE FAR WEST.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
AS OF 400 PM EDT MONDAY...
WEDGE OF VERY COOL HIGH PRESSURE WILL LIKELY PERSIST OVER MOST...IF
NOT ALL OF THE BLACKSBURG FORECAST AREA INTO/THROUGH WEDNESDAY AS
UPPER RIDGE BUILDS OVER EASTERN AND SOUTHEASTERN PORTION OF THE
NATION DOWNSTREAM OF APPROACHING TROF ADVANCING EAST FROM THE
NORTHERN PLAINS.
ABUNDANT MOISTURE TRAPPED UNDER A STEEP INVERSION IN THE LOWER 6K FT
OF THE TROPOSPHERE WILL ENSURE THAT TEMPERATURES OVER THE ENTIRE
FORECAST AREA REMAIN WELL BELOW NORMAL THROUGH THIS PERIOD...AND
ALSO WELL BELOW GUIDANCE...ESPECIALLY DURING THE DAYTIME PERIODS.
EAST TO SOUTHEAST LOWER TROPOSPHERIC FLOW AROUND THE PERIPHERY OF
THE SURFACE RIDGE TO THE NORTHEAST...AND ADVANCING LOW PRESSURE TO
THE WEST WILL RESULT IN FORCED ASCENT THROUGH A SATURATED LOWER
LAYER TO WRING OUT SPOTTY VERY LIGHT RAIN OR FREEZING
RAIN/DRIZZLE...MAXIMIZED ALONG AND MAINLY EAST OF THE BLUE RIDGE.
WARM NOSE AT TOP OF INVERSION LAYER SUFFICIENTLY ABOVE
FREEZING...AND WITH NO MID/HIGH LEVEL CLOUDS TO SUPPORT SEEDER-
FEEDER PROCESSES THROUGH DENDRITIC LEVEL...PRECIPITATION THIS TIME
AROUND WILL BE ALL LIQUID AS OPPOSED TO SNOW/SLEET.
OVERALL AMOUNTS OF MEASURABLE PRECIPITATION TUESDAY NIGHT INTO
WEDNESDAY WILL BE MEAGER...PERHAPS ONLY A FEW HUNDREDTHS OF AN INCH
IN MOST LOCATIONS...BUT STILL ENOUGH TO RESULT IN SOME GLAZING OF
ELEVATED EXPOSED SURFACES...AGAIN MAXIMIZED ACROSS THE EASTERN
FLANKS OF THE APPALACHIANS. AS A RESULT...MAY AGAIN HAVE TO POST
ANOTHER WINTER WEATHER ADVISORY IN SOME LOCATIONS FOR TUESDAY NIGHT
INTO WEDNESDAY MORNING...BUT WILL HOLD OFF UNTIL CURRENT HEADLINES
IN NEAR-TERM PERIOD EXPIRE SO AS TO NOT CONFUSE THE ISSUE...AND
HIGHLIGHT IN HAZARDOUS WEATHER OUTLOOK FOR NOW.
TROF AND ASSOCIATED COOL FRONT FORECAST TO SWEEP EAST THROUGH THE
BLACKSBURG FORECAST AREA BY/DURING WEDNESDAY NIGHT...POSSIBLY
PRECEDED AND ACCOMPANIED BY SOME BRIEF SPOTTY SHOWERS...MAINLY
ACROSS THE WESTERN FLANKS OF THE APPALACHIANS WEDNESDAY
AFTERNOON...GRADUALLY TRANSITIONING TO SOME UPSLOPE RAIN/SNOW
SHOWERS AS COLDER AIR FINALLY ARRIVES LATER WEDNESDAY NIGHT.
REGARDLESS...ARRIVAL OF COLD FRONT WILL ACTUALLY HELP TO SCOUR OUT
TENACIOUS COOL WEDGE OVER AREA...SUCH THAT TEMPERATURES MAY ACTUALLY
SPIKE WITH ONSET OF MIXING BEFORE TRAILING OFF AGAIN LATER WEDNESDAY
NIGHT.
SURFACE HIGH PRESSURE BUILDING INTO THE AREA FROM THE WEST THURSDAY
INTO THURSDAY NIGHT WILL RESULT IN CLEARING SKIES AND A RETURN TO
TEMPERATURES CLOSER TO SEASONAL AVERAGES.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 400 PM EDT SUNDAY...
MAINLY DRY AND SEASONAL WEATHER EXPECTED IN THE FRIDAY/FRIDAY NIGHT
TIMEFRAME AS SURFACE RIDGE MOVES OVER AND THEN TO THE EAST OF THE
FORECAST AREA.
APPROACH OF YET ANOTHER WAVE IN THE NORTHERN STREAM IS THEN SET TO
PUSH EAST/SOUTHEAST THROUGH THE REGION ON SATURDAY...LIKELY
PRECEDED AND ACCOMPANIED BY SCATTERED SHOWERS.
BELOW NORMAL TEMPERATURES...BUT WITH A RETURN TO DRY WEATHER IS THEN
EXPECTED TO RETURN TO MOST AREAS IN THE SUNDAY/MONDAY
TIMEFRAME...WITH PERHAPS THE EXCEPTION OF THE WESTERN FLANKS OF THE
APPALACHIANS...WHERE SOME UPSLOPING CLOUDS...AND POSSIBLY EVEN SOME
SPOTTY RAIN/SNOW SHOWERS ARE POSSIBLE INTO EARLY NEXT WEEK.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
AS OF 830 PM EDT MONDAY...
STRONG WEDGE OF COLD HIGH PRESSURE WILL REMAIN THE DOMINANT
WEATHER FEATURE FOR OUR REGION THROUGH THE TAF VALID PERIOD. THIS
WILL RESULT IN WIDESPREAD MVFR-IFR CIGS. A SOUTHEAST COASTAL
SYSTEM TRACKING TO OFF THE NC COAST BY TUE AFTERNOON WILL SIMPLY
REINFORCE THE WEDGE WITH INCREASING NE FLOW. THROUGH 06Z...AREAS
OF FZRA AND IP WILL IMPACT NORTHWEST NC INTO SOUTHSIDE
VA...INCLUDING DAN. THEREAFTER IN THESE AREAS...AS WELL AS
THROUGHOUT THE REMAINDER OF THE CWA...EXPECT AREAS OF FZDZ AND
FZFG OVERNIGHT WITH RIME ICING ON EXPOSED SURFACES AND WIDESPREAD
MVFR VSBYS. WINDS NE-ENE 7-10KTS
OVERNIGHT...INCREASING...ESPECIALLY EAST OF THE BLUE RIDGE AFTER
DAYBREAK TUE...TO 10-13KTS WITH GUSTS TO 20KTS ACROSS THE BLUE
RIDGE.
MEDIUM TO HIGH CONFIDENCE IN CIGS AND VSBYS THROUGH THE TAF VALID
PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND DIR/SPD THROUGH THE TAF VALID
PERIOD.
.EXTENDED AVIATION DISCUSSION...
VFR CONDITIONS ARE FINALLY EXPECTED TO RETURN WEDNESDAY AFTERNOON
AND CONTINUE THROUGH FRIDAY. GUSTY WEST WINDS ARE EXPECTED
WEDNESDAY AFTERNOON AND EVENING. SUB VFR CONDITIONS MAY RETURN FOR
THE WEEKEND AS A CANADIAN COLD FRONT MOVES THROUGH THE REGION
ACCOMPANIED BY SHOWERS...THEN UPSLOPE FLOW AND COLDER
TEMPERATURES.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY UNTIL NOON EDT TUESDAY FOR VAZ011-
013>020-022>024-032>035-043>047-058-059.
FREEZING FOG ADVISORY UNTIL 10 AM EDT TUESDAY FOR VAZ007-009-
010-012.
NC...WINTER WEATHER ADVISORY UNTIL NOON EDT TUESDAY FOR NCZ001>006-
018>020.
WV...FREEZING FOG ADVISORY UNTIL 10 AM EDT TUESDAY FOR WVZ042>045.
&&
$$
SYNOPSIS...KK
NEAR TERM...KK/RAB
SHORT TERM...WERT
LONG TERM...WERT
AVIATION...KK/RAB
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1041 PM CDT MON MAR 17 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 915 PM CDT MON MAR 17 2014
NO CHANGES TO THE HEADLINE THIS EVENING.
INCOMING SYSTEM PROBLEMATIC...AND GET THE FEELING MODELS STILL
DON/T HAVE A GOOD HANDLE ON IT. NEW NAM STARTING TO COME IN...AND
FROM WHAT/S IN AWIPS THUS FAR...IT WL HAVE ANOTHER SWD
SHIFT/SLOWING OF THE SYSTEM...LIKELY ACCOMPANIED BY AT LEAST SOME
COOLING OF THE TEMPERATURE PROFILES ACRS THE FCST AREA. SYSTEM WAS
INITIALLY LOOKING LIKE SNOW N-C WI...MIX TO SNOW C-NE WI...AND
RAIN-TO-SNOW-AT-THE-END-OF-THE-EVENT IN E-C WI. BUT IT/S GETTING
TO THE POINT WHERE ANY FURTHER SWD SHIFT IN THE SYSTEM COULD
RESULT IN PRIMARILY A FZN PCPN EVENT OVER ALMOST THE WHOLE AREA.
WON/T BE MAKING ANY CHANGES TO THE WATCH BASED ON THE VERY LIMITED
AMNT OF THE 00Z DATASET THAT/S ARRIVED THUS FAR...BUT THE NEXT
SHIFT MAY NEED TO MAKE SOME CHANGES.
PRIOR TO THE ARRIVAL OF THE MAIN SYSTEM...NARROW BAND OF SNOW
SHOULD PERSIST ACRS THE GREAT LAKES RGN. IT SHOULD REMAIN
PRIMARILY N OF THE FCST AREA THROUGH TOMORROW...THOUGH IT MAY CLIP
VILAS COUNTY AT TIMES.
UPDATED PRODUCT SUITE WL BE OUT ASAP.
UPDATE
ISSUED AT 622 PM CDT MON MAR 17 2014
INITIAL WV OF PCPN DRIVEN BY ISENT LIFT AND AIDED BY TAIL OF
SHRTWV SHIFTG EWD AND OUT OF THE AREA. VERY DRY AIR AT LOW-LEVELS
BEING REINFORCED BY SELY FLOW. ANY REMAINING ACCUMULATING SNOWS WL
SHIFT UP TOWARD THE UPPER MICHIGAN BORDER...BUT EVEN THERE...
EXPECT A LULL IN THE PCPN OVERNIGHT. WL ADJUST THE FCST
ACCORDINGLY AND SEND UPDATED PRODUCT SUITE ASAP.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 309 PM CDT MON MAR 17 2014
IN A NUTSHELL...NO SIGNIFICANT CHANGES TO PREVIOUS FORECAST EXCEPT
TO TRIM BACK ON POPS ACROSS THE NORTHERN THIRD OF THE FORECAST
AREA ON TUESDAY AND TWEAK TIMING OF EXIT OF LIGHT SNOW AND SNOW
SHOWER ACTIVITY AFFECTING MUCH OF THE FORECAST AREA LATE THIS
AFTERNOON.
BROAD AND RELATIVELY ROBUST LOW TO MID-LEVEL WARM ADVECTION
ACROSS THE FORECAST AREA TODAY HAS LED TO LARGE AREA OF POORLY
ORGANIZED LIGHT SNOW AND SNOW SHOWER ACTIVITY. THIS PRECIPITATION
HAS BEEN BATTLING STUBBORN LAYER OF DRY AIR OVER EASTCENTRAL
WISCONSIN ALL DAY. BEST SATURATION HAS BEEN ACROSS THE WESTERN AND
NORTHERN PORTION OF THE FORECAST AREA. SURFACE OBSERVATIONS HAVE
BEEN SHOWING VISIBILITIES ACROSS NORTHCENTRAL WISCONSIN GENERALLY
IN THE 1 TO 2 MILE CATEGORY GENERALLY NORTH OF HIGHWAY 29 WHICH
SEEMS TO BE SUPPORTRED BY AREA WEB CAMS.
LATEST RAP AND TO LESSER EXTENT GFS CONTINUE TO SUGGEST AREA OF
MODEST AND MORE FOCUSED LIFT OVER CENTRAL WISCONSIN AND GRADUALLY
SHIFTS IT EAST INTO EARLY EVENING. GIVEN DRY LAYER HAS BEEN BEATEN
DOWN BY ONGOING LIGHT SNOW UPSTREAM AND MODEL FORECAST OF
PERSISTENT LIFT INTO EARLY EVENING...LIGHT SNOW SHOULD START TO
AFFECT THE NORTHEAST PORTION OF THE FORECAST OVER THE NEXT FEW
HOURS...ESPECIALLY NORTH OF GREEN BAY. DO NOT EXPECT MUCH MORE
THAN MAYBE AN INCH OR SO ACROSS THE NORTH FOR THE REMAINDER OF
THE AFTERNOON. RUC AND HRRR GENERALLY IN AGREEMENT ON ENDING LIGHT
SNOW FROM WEST TO EAST EARLY THIS EVENING...PROBABALY AROUND 01Z
TO 02Z.
SHORT-TERM GUIDANCE GENERALLY IN CONCERT ON A PERIOD OF DRY
CONDITIONS THROUGH ABOUT 09Z BEFORE BAND OF MORE ORGANIZED LIGHT
SNOW DEVELOPS FROM CENTRAL MINNESOTA TO NORTHERN WISCONSIN. THIS
INITIAL SNOW BAND FORCED BY WAA AND FRONTOGENESIS...MAY CLIP THE
NORTHERN PORTION OF THE FORECAST AREA ALONG AND NORTH OF HIGHWAY 2
TOWARD DAYBREAK. THEN AS THE AFTERNOON WEARS ON...BAND SHOULD
BEGIN TO ROTATE NORTHWARD INTO WESTERN UPPER MICHIGAN AND LAKE
SUPERIOR. FOR THE REMAINDER OF THE FORECAST AREA LOOKS MAINLY DRY
BUT CLOUDY. ALTHOUGH TEMPERATURES SHOULD REBOUND INTO THE UPPER
30S TO AROUND 40...BRISK EASTERLY WINDS WILL MAKE IT FEEL COLDER.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 309 PM CDT MON MAR 17 2014
FOCUS CONTINUES TO BE ON THE STORM SYSTEM TRACKING OVER THE
REGION TUESDAY NIGHT INTO WEDNESDAY. PRECIPITATION TYPE AS WELL AS
THE LONG DURATION OF THE EVENT PROVIDES A BIG CHALLENGE WITH
RESPECT TO TIMING OF HEADLINES...OR IF HEADLINES ARE NEEDED AT
THIS TIME.
WITH THE INITIAL WAA PCPN LIFTED NORTH OF THE AREA OR PERHAPS
OVER FAR NORTHERN WISCONSIN TUESDAY...MUCH OF THE FORECAST AREA AT THE
ONSET WILL SEE PCPN REDEVELOPING FROM SOUTHWEST TO NORTHEAST AS
THE STORM SYSTEM TRACKS NORTHEAST FROM IOWA. DRY FORECAST
SOUNDINGS TUESDAY AFTERNOON SATURATE QUICKLY TUESDAY EVENING TO
PRODUCE AN ASSORTMENT OF R/ZR/IP/S OVER LOCATIONS WITH MAINLY SNOW
OVER THE NORTH. WITH A RATHER WARM BOUNDARY...WILL KEEP THE ZR
WORDING MINIMAL. MODEL POSITION AND TIMING OF THE SURFACE AND
H850 LOWS STILL NOT SETTLED WHICH WILL IMPACT PCPN TYPE AS WELL AS
A REGION OF HEAVIER SNOW. IN ADDITION SLOWER START TO THE EVENT
WILL LIKELY SPREAD WARMER AIR NORTHWARD TO HOLD SNOW AMOUNTS DOWN
OVER CENTRAL AND NORTHEAST WISCONSIN.
BUT A BLEND OF GFS/ECMWF/NAM MODELS ARE IN FAIRLY GOOD AGREEMENT
WITH TRACKING THE H850 LOW OVER CENTRAL WISCONSIN TUESDAY NIGHT
INTO WEDNESDAY. THE H850 LOW AND SURFACE LOW ARE SLOWER ALONG
WITH A HINT OF A H500 NEGATIVE TROUGH FEATURE. WITH HEIGHT 700
TEMPS COLDEST OVER NORTHWEST WISCONSIN INCLUDING PARTS OF NORTH
CENTRAL WISCONSIN...WILL INCLUDE VILAS COUNTY IN A WINTER STORM
WATCH FOR NOW. THE UKMET AND GEM WERE A BIT FURTHER SOUTH WITH THE
SURFACE LOW AND IF THE OTHER MODELS TREND THAT WAY LATER
ON...ADJUSTMENTS WILL BE NEEDED WITH THE HEADLINES.
AFTER BLUSTERY DAY WEDNESDAY WITH SNOW DIMINISHING...A WEAK RIDGE
SLIDES OVER THURSDAY FOR COLD BUT QUIET CONDITIONS.
ANOTHER SHORT WAVE SLIDES OVER THE REGION FRIDAY INTO FRIDAY NIGHT
FOR ANOTHER CHANCE OF MAINLY SNOW. FOLLOWED BY COLDER AIR AND
DRIER CONDITIONS FOR THE WEEKEND.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1038 PM CDT MON MAR 17 2014
FCST AREA CURRENTLY WITHIN A LULL IN THE PCPN. LOOKS LIKE NEW SNOW
BAND REORGANIZING TO THE W...BUT THE FOCUS OF THAT BAND SHOULD
STAY MAINLY N OF THE TAF SITES THROUGH TOMORROW. THAT WL RESULT IN
PRIMARILY VFR CIGS ACRS THE AREA...THOUGH MVFR CIGS POSSIBLE AT
TIMES AT RHI. PCPN WL SPREAD BACK ACRS THE AREA TOMORROW
EVENING...WITH DETERIORATING FLIGHT CONDITIONS EXPECTED AT THAT
TIME.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY
AFTERNOON FOR WIZ005.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....ESB
LONG TERM......TDH
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
920 PM CDT MON MAR 17 2014
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 915 PM CDT MON MAR 17 2014
NO CHANGES TO THE HEADLINE THIS EVENING.
INCOMING SYSTEM PROBLEMATIC...AND GET THE FEELING MODELS STILL
DON/T HAVE A GOOD HANDLE ON IT. NEW NAM STARTING TO COME IN...AND
FROM WHAT/S IN AWIPS THUS FAR...IT WL HAVE ANOTHER SWD
SHIFT/SLOWING OF THE SYSTEM...LIKELY ACCOMPANIED BY AT LEAST SOME
COOLING OF THE TEMPERATURE PROFILES ACRS THE FCST AREA. SYSTEM WAS
INITIALLY LOOKING LIKE SNOW N-C WI...MIX TO SNOW C-NE WI...AND
RAIN-TO-SNOW-AT-THE-END-OF-THE-EVENT IN E-C WI. BUT IT/S GETTING
TO THE POINT WHERE ANY FURTHER SWD SHIFT IN THE SYSTEM COULD
RESULT IN PRIMARILY A FZN PCPN EVENT OVER ALMOST THE WHOLE AREA.
WON/T BE MAKING ANY CHANGES TO THE WATCH BASED ON THE VERY LIMITED
AMNT OF THE 00Z DATASET THAT/S ARRIVED THUS FAR...BUT THE NEXT
SHIFT MAY NEED TO MAKE SOME CHANGES.
PRIOR TO THE ARRIVAL OF THE MAIN SYSTEM...NARROW BAND OF SNOW
SHOULD PERSIST ACRS THE GREAT LAKES RGN. IT SHOULD REMAIN
PRIMARILY N OF THE FCST AREA THROUGH TOMORROW...THOUGH IT MAY CLIP
VILAS COUNTY AT TIMES.
UPDATED PRODUCT SUITE WL BE OUT ASAP.
UPDATE
ISSUED AT 622 PM CDT MON MAR 17 2014
INITIAL WV OF PCPN DRIVEN BY ISENT LIFT AND AIDED BY TAIL OF
SHRTWV SHIFTG EWD AND OUT OF THE AREA. VERY DRY AIR AT LOW-LEVELS
BEING REINFORCED BY SELY FLOW. ANY REMAINING ACCUMULATING SNOWS WL
SHIFT UP TOWARD THE UPPER MICHIGAN BORDER...BUT EVEN THERE...
EXPECT A LULL IN THE PCPN OVERNIGHT. WL ADJUST THE FCST
ACCORDINGLY AND SEND UPDATED PRODUCT SUITE ASAP.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 309 PM CDT MON MAR 17 2014
IN A NUTSHELL...NO SIGNIFICANT CHANGES TO PREVIOUS FORECAST EXCEPT
TO TRIM BACK ON POPS ACROSS THE NORTHERN THIRD OF THE FORECAST
AREA ON TUESDAY AND TWEAK TIMING OF EXIT OF LIGHT SNOW AND SNOW
SHOWER ACTIVITY AFFECTING MUCH OF THE FORECAST AREA LATE THIS
AFTERNOON.
BROAD AND RELATIVELY ROBUST LOW TO MID-LEVEL WARM ADVECTION
ACROSS THE FORECAST AREA TODAY HAS LED TO LARGE AREA OF POORLY
ORGANIZED LIGHT SNOW AND SNOW SHOWER ACTIVITY. THIS PRECIPITATION
HAS BEEN BATTLING STUBBORN LAYER OF DRY AIR OVER EASTCENTRAL
WISCONSIN ALL DAY. BEST SATURATION HAS BEEN ACROSS THE WESTERN AND
NORTHERN PORTION OF THE FORECAST AREA. SURFACE OBSERVATIONS HAVE
BEEN SHOWING VISIBILITIES ACROSS NORTHCENTRAL WISCONSIN GENERALLY
IN THE 1 TO 2 MILE CATEGORY GENERALLY NORTH OF HIGHWAY 29 WHICH
SEEMS TO BE SUPPORTRED BY AREA WEB CAMS.
LATEST RAP AND TO LESSER EXTENT GFS CONTINUE TO SUGGEST AREA OF
MODEST AND MORE FOCUSED LIFT OVER CENTRAL WISCONSIN AND GRADUALLY
SHIFTS IT EAST INTO EARLY EVENING. GIVEN DRY LAYER HAS BEEN BEATEN
DOWN BY ONGOING LIGHT SNOW UPSTREAM AND MODEL FORECAST OF
PERSISTENT LIFT INTO EARLY EVENING...LIGHT SNOW SHOULD START TO
AFFECT THE NORTHEAST PORTION OF THE FORECAST OVER THE NEXT FEW
HOURS...ESPECIALLY NORTH OF GREEN BAY. DO NOT EXPECT MUCH MORE
THAN MAYBE AN INCH OR SO ACROSS THE NORTH FOR THE REMAINDER OF
THE AFTERNOON. RUC AND HRRR GENERALLY IN AGREEMENT ON ENDING LIGHT
SNOW FROM WEST TO EAST EARLY THIS EVENING...PROBABALY AROUND 01Z
TO 02Z.
SHORT-TERM GUIDANCE GENERALLY IN CONCERT ON A PERIOD OF DRY
CONDITIONS THROUGH ABOUT 09Z BEFORE BAND OF MORE ORGANIZED LIGHT
SNOW DEVELOPS FROM CENTRAL MINNESOTA TO NORTHERN WISCONSIN. THIS
INITIAL SNOW BAND FORCED BY WAA AND FRONTOGENESIS...MAY CLIP THE
NORTHERN PORTION OF THE FORECAST AREA ALONG AND NORTH OF HIGHWAY 2
TOWARD DAYBREAK. THEN AS THE AFTERNOON WEARS ON...BAND SHOULD
BEGIN TO ROTATE NORTHWARD INTO WESTERN UPPER MICHIGAN AND LAKE
SUPERIOR. FOR THE REMAINDER OF THE FORECAST AREA LOOKS MAINLY DRY
BUT CLOUDY. ALTHOUGH TEMPERATURES SHOULD REBOUND INTO THE UPPER
30S TO AROUND 40...BRISK EASTERLY WINDS WILL MAKE IT FEEL COLDER.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 309 PM CDT MON MAR 17 2014
FOCUS CONTINUES TO BE ON THE STORM SYSTEM TRACKING OVER THE
REGION TUESDAY NIGHT INTO WEDNESDAY. PRECIPITATION TYPE AS WELL AS
THE LONG DURATION OF THE EVENT PROVIDES A BIG CHALLENGE WITH
RESPECT TO TIMING OF HEADLINES...OR IF HEADLINES ARE NEEDED AT
THIS TIME.
WITH THE INITIAL WAA PCPN LIFTED NORTH OF THE AREA OR PERHAPS
OVER FAR NORTHERN WISCONSIN TUESDAY...MUCH OF THE FORECAST AREA AT THE
ONSET WILL SEE PCPN REDEVELOPING FROM SOUTHWEST TO NORTHEAST AS
THE STORM SYSTEM TRACKS NORTHEAST FROM IOWA. DRY FORECAST
SOUNDINGS TUESDAY AFTERNOON SATURATE QUICKLY TUESDAY EVENING TO
PRODUCE AN ASSORTMENT OF R/ZR/IP/S OVER LOCATIONS WITH MAINLY SNOW
OVER THE NORTH. WITH A RATHER WARM BOUNDARY...WILL KEEP THE ZR
WORDING MINIMAL. MODEL POSITION AND TIMING OF THE SURFACE AND
H850 LOWS STILL NOT SETTLED WHICH WILL IMPACT PCPN TYPE AS WELL AS
A REGION OF HEAVIER SNOW. IN ADDITION SLOWER START TO THE EVENT
WILL LIKELY SPREAD WARMER AIR NORTHWARD TO HOLD SNOW AMOUNTS DOWN
OVER CENTRAL AND NORTHEAST WISCONSIN.
BUT A BLEND OF GFS/ECMWF/NAM MODELS ARE IN FAIRLY GOOD AGREEMENT
WITH TRACKING THE H850 LOW OVER CENTRAL WISCONSIN TUESDAY NIGHT
INTO WEDNESDAY. THE H850 LOW AND SURFACE LOW ARE SLOWER ALONG
WITH A HINT OF A H500 NEGATIVE TROUGH FEATURE. WITH HEIGHT 700
TEMPS COLDEST OVER NORTHWEST WISCONSIN INCLUDING PARTS OF NORTH
CENTRAL WISCONSIN...WILL INCLUDE VILAS COUNTY IN A WINTER STORM
WATCH FOR NOW. THE UKMET AND GEM WERE A BIT FURTHER SOUTH WITH THE
SURFACE LOW AND IF THE OTHER MODELS TREND THAT WAY LATER
ON...ADJUSTMENTS WILL BE NEEDED WITH THE HEADLINES.
AFTER BLUSTERY DAY WEDNESDAY WITH SNOW DIMINISHING...A WEAK RIDGE
SLIDES OVER THURSDAY FOR COLD BUT QUIET CONDITIONS.
ANOTHER SHORT WAVE SLIDES OVER THE REGION FRIDAY INTO FRIDAY NIGHT
FOR ANOTHER CHANCE OF MAINLY SNOW. FOLLOWED BY COLDER AIR AND
DRIER CONDITIONS FOR THE WEEKEND.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 622 PM CDT MON MAR 17 2014
BEST SNOWS NOW SHIFTG EWD AND OUT OF THE AREA...AND ALSO REFOCUSING
A BIT TOWARD THE UPPER MICHIGAN BORDER. EXPECT MAINLY VFR
CONDITIONS ACRS MOST OF THE AREA FOR THE REST OF THE NGT...THOUGH
SOME MVFR AND BRIEF IFR CONDITIONS WL BE FOUND IN THE FAR N AT
TIMES. HI-RESOLUTION MODELS PRESENTED SOME MIXED SIGNALS ON
WHETHER OR NOT WIND PROFILES WOULD REQUIRE LLWS IN THE TAFS. SITN
MARGINAL AT BEST...BUT INCLUDED LOW-END LLWS CONDITIONS ACRS
C/E-C WI OVERNIGHT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY
AFTERNOON FOR WIZ005.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....ESB
LONG TERM......TDH
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
628 PM CDT MON MAR 17 2014
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
AND NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 622 PM CDT MON MAR 17 2014
INITIAL WV OF PCPN DRIVEN BY ISENT LIFT AND AIDED BY TAIL OF
SHRTWV SHIFTG EWD AND OUT OF THE AREA. VERY DRY AIR AT LOW-LEVELS
BEING REINFORCED BY SELY FLOW. ANY REMAINING ACCUMULATING SNOWS WL
SHIFT UP TOWARD THE UPPER MICHIGAN BORDER...BUT EVEN THERE...
EXPECT A LULL IN THE PCPN OVERNIGHT. WL ADJUST THE FCST
ACCORDINGLY AND SEND UPDATED PRODUCT SUITE ASAP.
&&
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 309 PM CDT MON MAR 17 2014
IN A NUTSHELL...NO SIGNIFICANT CHANGES TO PREVIOUS FORECAST EXCEPT
TO TRIM BACK ON POPS ACROSS THE NORTHERN THIRD OF THE FORECAST
AREA ON TUESDAY AND TWEAK TIMING OF EXIT OF LIGHT SNOW AND SNOW
SHOWER ACTIVITY AFFECTING MUCH OF THE FORECAST AREA LATE THIS
AFTERNOON.
BROAD AND RELATIVELY ROBUST LOW TO MID-LEVEL WARM ADVECTION
ACROSS THE FORECAST AREA TODAY HAS LED TO LARGE AREA OF POORLY
ORGANIZED LIGHT SNOW AND SNOW SHOWER ACTIVITY. THIS PRECIPITATION
HAS BEEN BATTLING STUBBORN LAYER OF DRY AIR OVER EASTCENTRAL
WISCONSIN ALL DAY. BEST SATURATION HAS BEEN ACROSS THE WESTERN AND
NORTHERN PORTION OF THE FORECAST AREA. SURFACE OBSERVATIONS HAVE
BEEN SHOWING VISIBILITIES ACROSS NORTHCENTRAL WISCONSIN GENERALLY
IN THE 1 TO 2 MILE CATEGORY GENERALLY NORTH OF HIGHWAY 29 WHICH
SEEMS TO BE SUPPORTRED BY AREA WEB CAMS.
LATEST RAP AND TO LESSER EXTENT GFS CONTINUE TO SUGGEST AREA OF
MODEST AND MORE FOCUSED LIFT OVER CENTRAL WISCONSIN AND GRADUALLY
SHIFTS IT EAST INTO EARLY EVENING. GIVEN DRY LAYER HAS BEEN BEATEN
DOWN BY ONGOING LIGHT SNOW UPSTREAM AND MODEL FORECAST OF
PERSISTENT LIFT INTO EARLY EVENING...LIGHT SNOW SHOULD START TO
AFFECT THE NORTHEAST PORTION OF THE FORECAST OVER THE NEXT FEW
HOURS...ESPECIALLY NORTH OF GREEN BAY. DO NOT EXPECT MUCH MORE
THAN MAYBE AN INCH OR SO ACROSS THE NORTH FOR THE REMAINDER OF
THE AFTERNOON. RUC AND HRRR GENERALLY IN AGREEMENT ON ENDING LIGHT
SNOW FROM WEST TO EAST EARLY THIS EVENING...PROBABALY AROUND 01Z
TO 02Z.
SHORT-TERM GUIDANCE GENERALLY IN CONCERT ON A PERIOD OF DRY
CONDITIONS THROUGH ABOUT 09Z BEFORE BAND OF MORE ORGANIZED LIGHT
SNOW DEVELOPS FROM CENTRAL MINNESOTA TO NORTHERN WISCONSIN. THIS
INITIAL SNOW BAND FORCED BY WAA AND FRONTOGENESIS...MAY CLIP THE
NORTHERN PORTION OF THE FORECAST AREA ALONG AND NORTH OF HIGHWAY 2
TOWARD DAYBREAK. THEN AS THE AFTERNOON WEARS ON...BAND SHOULD
BEGIN TO ROTATE NORTHWARD INTO WESTERN UPPER MICHIGAN AND LAKE
SUPERIOR. FOR THE REMAINDER OF THE FORECAST AREA LOOKS MAINLY DRY
BUT CLOUDY. ALTHOUGH TEMPERATURES SHOULD REBOUND INTO THE UPPER
30S TO AROUND 40...BRISK EASTERLY WINDS WILL MAKE IT FEEL COLDER.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 309 PM CDT MON MAR 17 2014
FOCUS CONTINUES TO BE ON THE STORM SYSTEM TRACKING OVER THE
REGION TUESDAY NIGHT INTO WEDNESDAY. PRECIPITATION TYPE AS WELL AS
THE LONG DURATION OF THE EVENT PROVIDES A BIG CHALLENGE WITH
RESPECT TO TIMING OF HEADLINES...OR IF HEADLINES ARE NEEDED AT
THIS TIME.
WITH THE INITIAL WAA PCPN LIFTED NORTH OF THE AREA OR PERHAPS
OVER FAR NORTHERN WISCONSIN TUESDAY...MUCH OF THE FORECAST AREA AT THE
ONSET WILL SEE PCPN REDEVELOPING FROM SOUTHWEST TO NORTHEAST AS
THE STORM SYSTEM TRACKS NORTHEAST FROM IOWA. DRY FORECAST
SOUNDINGS TUESDAY AFTERNOON SATURATE QUICKLY TUESDAY EVENING TO
PRODUCE AN ASSORTMENT OF R/ZR/IP/S OVER LOCATIONS WITH MAINLY SNOW
OVER THE NORTH. WITH A RATHER WARM BOUNDARY...WILL KEEP THE ZR
WORDING MINIMAL. MODEL POSITION AND TIMING OF THE SURFACE AND
H850 LOWS STILL NOT SETTLED WHICH WILL IMPACT PCPN TYPE AS WELL AS
A REGION OF HEAVIER SNOW. IN ADDITION SLOWER START TO THE EVENT
WILL LIKELY SPREAD WARMER AIR NORTHWARD TO HOLD SNOW AMOUNTS DOWN
OVER CENTRAL AND NORTHEAST WISCONSIN.
BUT A BLEND OF GFS/ECMWF/NAM MODELS ARE IN FAIRLY GOOD AGREEMENT
WITH TRACKING THE H850 LOW OVER CENTRAL WISCONSIN TUESDAY NIGHT
INTO WEDNESDAY. THE H850 LOW AND SURFACE LOW ARE SLOWER ALONG
WITH A HINT OF A H500 NEGATIVE TROUGH FEATURE. WITH HEIGHT 700
TEMPS COLDEST OVER NORTHWEST WISCONSIN INCLUDING PARTS OF NORTH
CENTRAL WISCONSIN...WILL INCLUDE VILAS COUNTY IN A WINTER STORM
WATCH FOR NOW. THE UKMET AND GEM WERE A BIT FURTHER SOUTH WITH THE
SURFACE LOW AND IF THE OTHER MODELS TREND THAT WAY LATER
ON...ADJUSTMENTS WILL BE NEEDED WITH THE HEADLINES.
AFTER BLUSTERY DAY WEDNESDAY WITH SNOW DIMINISHING...A WEAK RIDGE
SLIDES OVER THURSDAY FOR COLD BUT QUIET CONDITIONS.
ANOTHER SHORT WAVE SLIDES OVER THE REGION FRIDAY INTO FRIDAY NIGHT
FOR ANOTHER CHANCE OF MAINLY SNOW. FOLLOWED BY COLDER AIR AND
DRIER CONDITIONS FOR THE WEEKEND.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 622 PM CDT MON MAR 17 2014
BEST SNOWS NOW SHIFTG EWD AND OUT OF THE AREA...AND ALSO REFOCUSING
A BIT TOWARD THE UPPER MICHIGAN BORDER. EXPECT MAINLY VFR
CONDITIONS ACRS MOST OF THE AREA FOR THE REST OF THE NGT...THOUGH
SOME MVFR AND BRIEF IFR CONDITIONS WL BE FOUND IN THE FAR N AT
TIMES. HI-RESOLUTION MODELS PRESENTED SOME MIXED SIGNALS ON
WHETHER OR NOT WIND PROFILES WOULD REQUIRE LLWS IN THE TAFS. SITN
MARGINAL AT BEST...BUT INCLUDED LOW-END LLWS CONDITIONS ACRS
C/E-C WI OVERNIGHT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY
AFTERNOON FOR WIZ005.
&&
$$
UPDATE.........SKOWRONSKI
SHORT TERM.....ESB
LONG TERM......TDH
AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
455 AM EDT TUE MAR 18 2014
.SYNOPSIS...
LOW PRESSURE OFF THE FLORIDA COAST EARLY THIS MORNING WILL MOVE
AWAY FROM THE SOUTHEAST STATES TODAY WHILE HIGH PRESSURE ACROSS THE
MID ATLANTIC STATES REMAINS IN PLACE THROUGH TONIGHT. BROAD HIGH
PRESSURE WILL CONTINUE OVER THE REGION THROUGH FRIDAY...BEFORE A
COLD FRONT SHIFTS THROUGH THE AREA LATE THIS WEEKEND.. HIGH
PRESSURE WILL THEN BUILD OVER THE AREA INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
PRE-DAWN...LATEST RAP ANALYSIS AT 07Z SHOWS A POTENT VORT MAX
IN THE 700 MB TO 300 MB LAYER PUNCHING ALONG THE FLORIDA PANHANDLE
WHILE STRONGEST MID LEVEL HEIGHT FALLS FORECAST TO PUNCH THROUGH
FAR SOUTH GEORGIA AND NE FLORIDA PRIOR TO DAYBREAK. SURFACE LOW
PRES WAS CONGEALING RIGHT OFF THE NORTH CENTRAL FLORIDA COAST AND
WILL PRESS ENE AWAY FROM THE NE FLORIDA COAST THE NEXT FEW HOURS.
RAINFALL WAS BECOMING A BIT MORE CONVECTIVE WITH INCREASED UPPER
FORCING AND THE ARRIVAL OF THE UPPER DISTURBANCE. RAINFALL
OVERNIGHT HAS BEEN MORE PREVALENT OVER THE ADJACENT WATERS AND
CLOSER TO THE FRONT LEFT QUADRANT OF A STRONG UPPER JET MOVING THE
EASTERN GULF AND INTO FLORIDA. HIGHEST POPS THROUGH DAWN OVER SE
GEORGIA AND BRUSHING COASTAL SOUTH CAROLINA. FAR INLAND ZONES N OF
I-16 MAY NOT SEE TOO MUCH MORE RAINFALL GIVEN LATEST MODEL TRENDS.
A CHILLY AND DAMP MORNING WITH TEMPS 38-43 DEGREES AND BREEZY
CONDITIONS AT TIMES ALONG SOME COASTAL AREAS AS THE LOW DEVELOPS
OFF TO THE SOUTH WITH A GOOD WEDGE IN PLACE TO THE LEE OF THE
MOUNTAINS PINCHING THE GRADIENT. LOW LEVEL WINDS LOOK TOO
SUBSTANTIAL TO EXPECT THE STRATUS TO BUILD DOWN AND POSE A FOG
POTENTIAL NEAR DAWN.
TODAY...RAIN CHANCES EXPECTED TO DIMINISH AT A GOOD CLIP AFTER
MID/LATE MORNING THROUGH THE AFTERNOON AS THE SURFACE LOW AND UPPER
FORCING FOR ASCENT PULL AWAY. SINCE MODELS KEEP A WEAK DEFORMATION
ZONE ALONG COASTAL SOUTH CAROLINA THROUGH MID AFTERNOON...WE DID
MAINTAIN SOME CHANCE POPS JUST A BIT LONGER THAN THE PREVIOUS
FORECAST FOR LIGHT RAINS ALONG AND E OF I-95 IN THE 14Z TO 17Z
TIME RANGE.
FORECAST SOUNDINGS INDICATE THAT THE REMNANT WEDGE INVERSION WILL
ENSURE THAT RAPID CLEARING WILL NOT OCCUR DESPITE PLENTY OF DEEP
LAYERED DRY AIR MOVING IN ATOP THE SHALLOW MOIST INVERSION. THE
SYNOPTIC PATTERN SUGGESTS HIGH TEMPS WILL STRUGGLE TODAY WITH THE
CAVEAT OF POSSIBLE LATE DAY PARTIAL CLEARING WHICH MODELS HINT AT
AFTER 21Z. WE LOWERED HIGHS A TAD TO TREND A BIT PESSIMISTIC WITH
LATE DAY CLEARING POTENTIAL.
STEADY N TO NNE WINDS DURING THE MORNING HOURS SHOULD DIMINISH
THIS AFTERNOON AS THE PRES GRADIENT TENDS TO WEAKEN.
TONIGHT...MODELS DIFFER ON LOW LEVEL MOISTURE FIELDS AND LOW
CLOUD POTENTIAL. OUR FORECAST LOWS WERE BETWEEN THE COLDER NAM
WHICH SHOWS ONLY SCATTERED CLOUDS MOST OF THE NIGHT AND THE
WARMER GFS WHICH INDICATES WIDESPREAD CLOUDS PREVAILING. RAIN
CHANCES SLIM BUT SOME PATCHY LIGHT DRIZZLE CANNOT BE COMPLETELY
RULED OUT TOWARD DAYBREAK.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
WEDNESDAY THROUGH FRIDAY...A DRY AND MAINLY ZONAL FLOW WILL SET UP
OVER THE SOUTHEASTERN UNITED STATES BY MIDWEEK AND WILL LIKELY
PERSIST THROUGH EARLY WEEKEND. AT THE SFC...A WEDGE OF HIGH PRESSURE
WILL GRADUALLY WEAKEN WEDNESDAY AFTERNOON AS THE PARENT HIGH
PRESSURE CENTER SLIDES OFF THE NORTHEAST COAST AHEAD OF A LOW
PRESSURE SYSTEM TRACKING OVER THE GREAT LAKES REGION. THE PATTERN
CHANGE WILL LIKELY RESULT IN LESS CLOUD COVER AND WARMER TEMPS AS
LIGHT WEST/SOUTHWEST WINDS DEVELOP ALONG THE EDGE OF BROAD HIGH
PRESSURE FILTERING IN FROM THE WEST. OVERALL HIGH TEMPS SHOULD RANGE
IN THE LOW TO MID 70S ON WEDNESDAY...HIGHEST OVER SOUTHEAST GEORGIA.
A WEAK AND DRY COLD FRONT SHOULD THEN PASS NORTH OF THE AREA
WEDNESDAY NIGHT WITH LITTLE TO NO CHANGE IN TEMPS OVER THE AREA.
CLEARING SKIES SHOULD RESULT IN FAIR RADIATIONAL COOLING AND
OVERNIGHT TEMPS IN THE UPPER 40S INLAND TO LOW/MID 50S NEAR THE
COAST.
HIGH PRESSURE WILL CONTINUE TO SLIDE OVER THE SOUTHEAST UNITED
STATES ON THURSDAY...WITH A MORE FAVORABLE DOWNSLOPING WIND
COMPONENT OVER THE FORECAST AREA. TEMPS SHOULD THEREFORE BE A DEGREE
OR TWO WARMER THAN THE PREVIOUS DAY...WITH OVERALL HIGH TEMPS IN THE
MID 70S FOR MOST LOCATIONS. THURSDAY NIGHT LOWS WILL LIKELY BE
COOLER DUE TO MORE FAVORABLE RADIATIONAL COOLING CONDITIONS. THURSDAY
NIGHT LOWS SHOULD RANGE IN THE LOW/MID 40S AWAY FROM THE COAST. DRY
CONDITIONS AND SLOWLY MODIFYING TEMPS WILL LIKELY PERSIST THROUGH
MUCH OF FRIDAY AS HIGH PRESSURE SLIDES OFF THE SOUTHEAST COAST.
TEMPS SHOULD AGAIN PEAK INTO THE MID 70S...WARMEST AWAY FROM THE
COAST DUE TO AN ONSHORE WIND OVER COOLER WATERS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
A WARM-UP IS ANTICIPATED ON SATURDAY AS SOUTHERLY FLOW OCCURS OVER
THE AREA BETWEEN HIGH PRESSURE SHIFTING OFFSHORE AND A COLD FRONT
APPROACHING FROM THE NORTHWEST. IN GENERAL...OVERALL TEMPS SHOULD
APPROACH THE MID/UPPER 70S WITH COMPRESSIONAL HEATING IN ADVANCE OF
THE COLD FRONT. SATURDAY NIGHT LOWS SHOULD BE MILD...IN THE LOW/MID
50S. THE NEXT BEST CHANCE OF PRECIP SHOULD OCCUR SATURDAY NIGHT INTO
SUNDAY MORNING AS A COLD FRONT SHIFTS THROUGH THE SOUTHEASTERN
UNITED STATES. BELOW NORMAL TEMPS ARE THEN EXPECTED POST FROPA AS
HIGH PRESSURE BUILDS OVER THE REGION FROM THE NORTHWEST INTO EARLY
NEXT WEEK. AFTERNOON HIGHS TEMPS SHOULD RANGE IN THE FROM THE LOW
60S NORTH TO MID/UPPER 60S IN SOUTHEAST GEORGIA EARLY NEXT WEEK.
OVERNIGHT LOWS SHOULD RANGE IN THE LOW 40S INLAND TO MID/UPPER 40S
ALONG THE COAST. BY TUESDAY...PRECIP CHANCES COULD RETURN OVER THE
SOUTHEAST AS A SERIES OF MID LVL SHORTWAVES SHIFT OVER THE AREA
WHILE A SFC LOW DEVELOPS AND TRACKS ALONG THE SOUTHEAST COAST.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
IFR/LIFR CEILINGS ARE EXPECTED THROUGH THE NIGHT INTO TUESDAY
MORNING AS INVERSION FROM THE WEDGE LOCKING IN LOW CLOUDS. THE
MAIN BAND OF RAINS SHOULD REMAIN ALONG THE COASTAL CORRIDOR
OVERNIGHT WITH PERIODS OF RAIN AND DRIZZLE. SURFACE WINDS WILL
OCCASIONALLY GUST 17-20 KT AS THE PRES GRADIENT IS QUITE TIGHT.
THE ONLY CHANGES TO THE TAFS WE MADE AT 06Z MAINLY TO SLOW THE
ASCENT TO MVFR CONDITIONS THIS AFTERNOON GIVEN LATEST FORECAST
SOUNDINGS AND MODEL TRENDS. IFR CIGS COULD HANG IN MUCH OF THE
DAY BUT WE HAVE INDICATED BASES LIFTING ABOVE 1 KFT AFTER 19Z
TO TREND AT BOTH KSAV AND KCHS. LATER CYCLES MAY NEED TO SLOW
THE PROCESS A BIT MORE AS THE WEDGE REMAINS THE SIGNIFICANT
FEATURE BEHIND THE DEPARTING STORM SYSTEM.
EXTENDED AVIATION OUTLOOK...LOW CHANCES OF MVFR CIGS/VSBYS LATE
WEDNESDAY MORNING WITHIN A WEDGE OF HIGH PRESSURE OVER THE
SOUTHEAST. VFR CIGS/VSBYS SHOULD THEN RETURN AT BOTH TERMINALS
WEDNESDAY AFTERNOON AND PERSIST THROUGH LATE WEEK.
&&
.MARINE...
WINDS AND SEAS HAVE RESPONDED QUITE A BIT OVERNIGHT AS THE GRADIENT
HAS TIGHTENED BETWEEN DEVELOPING LOW PRES OFF THE FLORIDA COAST
AND THE SURFACE WEDGE OVER NE GEORGIA AND THE CAROLINAS. LATEST
OBSERVATIONS SHOW A SOLID SMALL CRAFT EVENT UNFOLDING WHICH SHOULD
LAST THROUGH MID MORNING. WE ARE WATCHING THE CHARLESTON HARBOR
WHICH IS CLOSE TO SCA CRITERIA. WE SHOULD BE ABLE TO INITIATE
WITH N 15-20 KT AND WAVES 1-2 FT BUT MAY NEED A SHORT DURATION
SCA IF CONDITIONS DETERIORATE FURTHER. SEAS WILL PEAK 7-9 FT
BEYOND 20 NM THIS MORNING AND START TO COME DOWN THIS AFTERNOON.
AS THE LOW PULLS AWAY THIS AFTERNOON THE WEDGE BEGINS TO ERODE...
WINDS AND SEAS SHOULD STEADILY SUBSIDE. NO CHANGES TO ENDING TIMES
FOR THE SCA LATER TODAY BUT WE DID EXTEND THE ADVISORY OVER OUR
20-60 NM WATERS THIS EVENING TO ALLOW A FEW MORE HOURS FOR SEAS TO
SUBSIDE.
WEDNESDAY THROUGH SATURDAY...WINDS/SEAS WILL REMAIN BELOW SMALL
CRAFT ADVISORY LEVEL CONDITIONS AS A WEDGE OF HIGH PRESSURE WEAKENS
INLAND ON WEDNESDAY AND IS REPLACED BY BROADER HIGH PRESSURE FROM
THE WEST THURSDAY THROUGH SATURDAY. IN GENERAL...NORTHEAST WINDS
WILL BECOME SOUTH/SOUTHWEST AS THE WEDGE WEAKENS...THEN REMAIN AT OR
BELOW 15 KT. SEAS WILL BE NO HIGHER THAN 3-5 FT...HIGHEST OVER
OUTER GEORGIA WATERS. WINDS/SEAS COULD GRADUALLY BUILD LATE THIS
WEEKEND AS A COLD FRONT APPROACHES THE WATERS FROM THE NORTHWEST.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EDT THIS AFTERNOON FOR AMZ352-
354.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR AMZ374.
SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR AMZ350.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...DPB
LONG TERM...DPB
AVIATION...
MARINE...DPB
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
433 AM EDT TUE MAR 18 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 AM EDT TUE MAR 18 2014
AFTER A DRY MILD DAY TODAY...RAIN SHOWERS WILL DEVELOP LATE TONIGHT
INTO WEDNESDAY AS A COLD FRONT MOVES THROUGH. COOLER DRIER WEATHER
IS EXPECTED FOR WEDNESDAY NIGHT AND THURSDAY. TEMPERATURES WILL ONCE
AGAIN TURN WARMER FOR FRIDAY WITH THE PASSAGE OF A WARM FRONT. RAIN
AND EMBEDDED THUNDERSTORMS WILL ACCOMPANY THE PASSAGE OF LOW
PRESSURE FRIDAY NIGHT. HIGH PRESSURE THEN REESTABLISHES FOR THE
WEEKEND WITH DRY AND PROGRESSIVELY COLDER AIR.
&&
.NEAR TERM /TODAY/...
ISSUED AT 336 AM EDT TUE MAR 18 2014
HIGH CLOUDS DRIFTING THROUGH EARLY THIS MORNING WITH WEAK HIGH
PRESSURE ACROSS THE OHIO VALLEY. LARGE AREA OF STRATUS MOVING W/NW
ACROSS KENTUCKY AS WELL. WITH LIGHT E/SE FLOW...TEMPS RANGED FROM
THE MID 20S TO LOWER 30S ACROSS THE FORECAST AREA AT 07Z.
INITIAL ISSUE FOCUSES ON THE STRATUS DECK EXPANDING TOWARDS THE
FORECAST AREA FROM THE SOUTHEAST. SHORT RANGE MODEL GUIDANCE
ADVECTING DEEPER MOISTURE INTO THE REGION THROUGH THE MORNING AS
LOW LEVEL FLOW VEERS TO A S/SE DIRECTION. AT THE SAME TIME...BOTH
THE RAP AND NAM APPEAR TO BE OVERDOING MOISTURE ON THE 925/950 MB
LEVELS VERSUS THE LEADING EDGE OF THE CURRENT STRATUS DECK AS OF
07Z. CONFIDENCE IS GROWING IN LOWER CLOUDS REACHING THE SOUTHEASTERN
PORTIONS OF THE FORECAST AREA OVER THE NEXT FEW HOURS...AND POSSIBLY
GETTING AS FAR NORTH AS I-70 OVER THE EASTERN HALF OF CENTRAL
INDIANA AFTER DAYBREAK. WILL INCREASE CLOUD COVERAGE GRIDS SOUTHEAST
OF THE INDY METRO FOR THE MORNING AND MONITOR FOR ANY ADDITIONAL
UPDATES OVER THE NEXT FEW HOURS.
ELSEWHERE ACROSS CENTRAL INDIANA...MID AND HIGH LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN ADVANCE OF LOW PRESSURE
TRACKING THROUGH THE CENTRAL PLAINS. EXPECT AN INCREASE IN SURFACE
WINDS BY THIS AFTERNOON AS THE LOW APPROACHES...WITH SUSTAINEDS TO
NEAR 15MPH BY LATE DAY.
TEMPS...EVENTUAL EXTENT OF STRATUS DECK BOTH IN COVERAGE AND TIME
WILL BE CRITICAL...AS THEY WERE ON MONDAY...ON DETERMINING HOW WARM
TEMPS GO OVER THE SOUTHEASTERN PORTIONS OF THE FORECAST AREA. WITH
WARM ADVECTION TODAY...LOW LEVEL THERMALS SUPPORTIVE OF MAX TEMPS IN
THE LOWER/MIDDLE 50S. GENERALLY NEAR MAVMOS GUIDANCE...ALTHOUGH DID
UNDERCUT MAV BY A FEW DEGREES OVER SOUTHERN COUNTIES WITH POTENTIAL
IMPACTS FROM CLOUDS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 336 AM EDT TUE MAR 18 2014
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TONIGHT/WEDNESDAY AND
AGAIN THURSDAY NIGHT WITH TWO SYSTEMS IMPACTING THE REGION.
LOW PRESSURE WILL PINWHEEL INTO THE GREAT LAKES WEDNESDAY AND SWING
A COLD FRONT ACROSS CENTRAL INDIANA DURING THE MORNING. MOISTURE
FETCH IS LIMITED OVERALL BUT FORCING THROUGH THE BOUNDARY LAYER AND
DIFFLUENCE ALOFT SHOULD BE MORE THAN SUFFICIENT FOR PRECIP TO
DEVELOP LATE TONIGHT INTO WEDNESDAY MORNING. STRENGTHENING LOW LEVEL
JET WILL ROTATE ACROSS CENTRAL INDIANA LATE TONIGHT AND PROMOTE A
BRIEF PERIOD WITH ISENTROPIC LIFT AHEAD OF THE FRONT AS WELL. WILL
CARRY LIKELY POPS OVER NORTHERN COUNTIES LATE TONIGHT AND WEDNESDAY
MORNING IN CLOSEST PROXIMITY TO BETTER FORCING AND DEEPER MOISTURE
WITH CHANCE POPS FURTHER SOUTH ACROSS THE FORECAST AREA. POTENTIAL
EXISTS FOR A CONVECTIVE COMPONENT TO PRECIP AND POTENTIALLY A FEW
RUMBLES OF THUNDER OVER THE NORTHERN WABASH VALLEY AS SOME ELEVATED
INSTABILITY WILL BE PRESENT.
BIG ISSUE WITH THE PASSAGE OF THE COLD FRONT WILL BE THE WINDS. THE
LOW LEVEL JET MOVING ACROSS THE REGION LATE TONIGHT WILL PROMOTE
GUSTS INCREASING TO 20-30MPH...BUT PRESENCE OF A BOUNDARY LAYER
INVERSION SHOULD LIMIT WHAT MAKES IT TO THE GROUND. AS COLD
ADVECTION TAKES HOLD ONCE THE FRONT GOES BY WEDNESDAY MORNING
HOWEVER...MODEL SOUNDINGS SHOW AN ENVIRONMENT CONDUCIVE FOR STRONGER
WINDS ALOFT BEING PULLED TO THE SURFACE AS STEEPENING LAPSE RATES
PROMOTE EXCELLENT LOW LEVEL MIXING. MAX GUSTS OF 35-40 MPH LIKELY
DURING THE AFTERNOON...AND MAY APPROACH WIND ADVISORY CRITERIA AS
WELL. WILL MAINTAIN LOW CHANCE POPS THROUGH THE AFTERNOON WITH
SUBTLE INSTABILITY PRESENT.
ANY PRECIP CHANCES WILL END BY WEDNESDAY NIGHT AS THE LOW LIFTS OUT
TO THE NORTHEAST AND IS REPLACED BY A SURFACE RIDGE. EXPECT DRY
CONDITIONS TO PERSIST INTO THURSDAY EVENING AS THE RIDGE PASSES
THROUGH THE OHIO VALLEY. A WARM FRONT WILL MOVE INTO THE REGION
THURSDAY NIGHT AIDED BY A 30-40KT LOW LEVEL JET. NICE AXIS OF LOW
LEVEL CONVERGENCE AND ISENTROPIC LIFT DEVELOPING AT THE NOSE OF THE
JET ACROSS THE NORTHERN HALF OF THE FORECAST AREA WILL SUPPORT SOME
RAIN SHOWER DEVELOPMENT ALONG THE WARM FRONT. MOST OF THE PRECIP
SHOULD MOVE NORTH OF THE FORECAST AREA WITH THE BOUNDARY BY 12Z
FRIDAY.
TEMPS...HIGHS EXPECTED BY MIDDAY WEDNESDAY WITH SLOWLY FALLING TEMPS
THEREAFTER WITHIN THE COLD ADVECTION. PREFERRED COLDER MAVMOS HIGHS.
MAVMOS WAS ALSO PREFERRED FOR THURSDAY AS TEMPS EXPECTED TO RECOVER
NICELY INTO THE 50S WITH WARM ADVECTION DEVELOPING IN ADVANCE OF THE
WARM FRONT LATE DAY. MOS GUIDANCE APPEARED REASONABLE FOR LOWS
THROUGHOUT THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
ISSUED AT 310 AM EDT TUE MAR 18 2014
MODELS CONTINUE TO SUGGEST A PROGRESSIVE PATTERN DURING THE LONG
TERM PORTION OF THE FORECAST...WITH A LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT FRIDAY INTO FRIDAY NIGHT...AND ANOTHER ONE
EARLY NEXT WEEK.
FIRST SYSTEM FRIDAY INTO FRIDAY NIGHT MAY BRING A FEW
THUNDERSTORMS AS K INDICES AS HIGH AS 30 PLUS INDICATE A HEALTHY
PREFRONTAL INSTABILITY AXIS FRIDAY EVENING. EARLY NEXT WEEK SYSTEM
IS MUCH MORE BORDERLINE TEMPERATURE WISE...AND WILL CARRY RAIN OR
SNOW FOR NOW.
TEMPERATURES WILL BEGIN QUITE WARM IN THE STRONG WARM ADVECTION
AHEAD OF THE FRONT...BEFORE BECOMING NEAR TO BELOW NORMAL OVER THE
WEEKEND. NEAR TO JUST BEYOND THE SEVEN DAY FORECAST
PERIOD...GUIDANCE SUGGESTS POTENTIAL FOR YET ANOTHER COLD
INTRUSION FROM THE WINTER THAT REFUSES TO END.
&&
.AVIATION /DISCUSSION FOR THE 18/09Z TAF UPDATE/...
ISSUED AT 433 AM EDT TUE MAR 18 2014
PUSHED BACK ARRIVAL TIME OF LOW STRATUS AT IND/BMG. DIRECT
EXTRAPOLATION BRINGS IT HERE BY 16-18Z...BUT EXPECT SOME DEVELOPMENT
MAY OCCUR ON THE LEADING EDGE. PUSHED IT BACK TO 12Z AT BOTH SITES
AND WILL REEVALUATE FOR THE 12Z PACKAGE. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 1256 AM EDT TUE MAR 18 2014
LOW TO MEDIUM CONFIDENCE FORECAST. VFR WILL BECOME MVFR LATE TONIGHT
ACROSS EASTERN SITES. VFR SHOULD RETURN BY AFTERNOON...BUT MVFR
POSSIBLE LATE TUESDAY AFTERNOON.
SOME CLOUDS AROUND 3000FT REMAIN RELATIVELY CLOSE TO THE
SOUTHEAST...BUT EVEN LARGER CLOUD DECK FARTHER SOUTHEAST IS ALREADY
MOVING BACK NORTHWEST. ALSO...SHORT RANGE MODELS AND ENSEMBLES ARE
SHOWING MVFR DECK MOVING BACK IN TONIGHT.
THEREFORE HAVE ADDED A PERIOD OF MVFR CEILINGS LATE TONIGHT AT KIND
AND KBMG. NOT CONFIDENT ENOUGH YET TO ADD TO WESTERN SITES...BUT IT
IS STILL CERTAINLY POSSIBLE THAT DECK COULD SNEAK THAT FAR WEST.
CEILINGS AS LOW AS BKN010 NOT OUT OF THE QUESTION WITH THIS DECK.
CONFIDENCE IS STILL LOW TO MEDIUM.
NOT SURE ABOUT FOG DEVELOPMENT AS FORECAST SOUNDINGS INDICATE BETTER
CHANCES FOR STRATUS THAN FOG...BUT FOR NOW HAVE KEPT 6SM LATE
TONIGHT.
ANY LOWER CLOUDS SHOULD SCATTER OUT TUESDAY MORNING...BUT MOISTURE
MOVING IN AHEAD OF THE NEXT SYSTEM COULD BRING MVFR CEILINGS LATER
TUESDAY AFTERNOON AND TUESDAY EVENING. FOR NOW HAVE JUST PUT THEM AT
KBMG BEFORE 00Z WEDNESDAY AND LOW VFR ELSEWHERE AFTER 00Z.
WINDS WILL GUST TO AROUND 20KT AFTER 15Z TUESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...50/NIELD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
336 AM EDT TUE MAR 18 2014
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED
BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 AM EDT TUE MAR 18 2014
AFTER A DRY MILD DAY TODAY...RAIN SHOWERS WILL DEVELOP LATE TONIGHT
INTO WEDNESDAY AS A COLD FRONT MOVES THROUGH. COOLER DRIER WEATHER
IS EXPECTED FOR WEDNESDAY NIGHT AND THURSDAY. TEMPERATURES WILL ONCE
AGAIN TURN WARMER FOR FRIDAY WITH THE PASSAGE OF A WARM FRONT. RAIN
AND EMBEDDED THUNDERSTORMS WILL ACCOMPANY THE PASSAGE OF LOW
PRESSURE FRIDAY NIGHT. HIGH PRESSURE THEN REESTABLISHES FOR THE
WEEKEND WITH DRY AND PROGRESSIVELY COLDER AIR.
&&
.NEAR TERM /TODAY/...
ISSUED AT 336 AM EDT TUE MAR 18 2014
HIGH CLOUDS DRIFTING THROUGH EARLY THIS MORNING WITH WEAK HIGH
PRESSURE ACROSS THE OHIO VALLEY. LARGE AREA OF STRATUS MOVING W/NW
ACROSS KENTUCKY AS WELL. WITH LIGHT E/SE FLOW...TEMPS RANGED FROM
THE MID 20S TO LOWER 30S ACROSS THE FORECAST AREA AT 07Z.
INITIAL ISSUE FOCUSES ON THE STRATUS DECK EXPANDING TOWARDS THE
FORECAST AREA FROM THE SOUTHEAST. SHORT RANGE MODEL GUIDANCE
ADVECTING DEEPER MOISTURE INTO THE REGION THROUGH THE MORNING AS
LOW LEVEL FLOW VEERS TO A S/SE DIRECTION. AT THE SAME TIME...BOTH
THE RAP AND NAM APPEAR TO BE OVERDOING MOISTURE ON THE 925/950 MB
LEVELS VERSUS THE LEADING EDGE OF THE CURRENT STRATUS DECK AS OF 07Z.
CONFIDENCE IS GROWING IN LOWER CLOUDS REACHING THE SOUTHEASTERN
PORTIONS OF THE FORECAST AREA OVER THE NEXT FEW HOURS...AND POSSIBLY
GETTING AS FAR NORTH AS I-70 OVER THE EASTERN HALF OF CENTRAL
INDIANA AFTER DAYBREAK. WILL INCREASE CLOUD COVERAGE GRIDS SOUTHEAST
OF THE INDY METRO FOR THE MORNING AND MONITOR FOR ANY ADDITIONAL
UPDATES OVER THE NEXT FEW HOURS.
ELSEWHERE ACROSS CENTRAL INDIANA...MID AND HIGH LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN ADVANCE OF LOW PRESSURE
TRACKING THROUGH THE CENTRAL PLAINS. EXPECT AN INCREASE IN SURFACE
WINDS BY THIS AFTERNOON AS THE LOW APPROACHES...WITH SUSTAINEDS TO
NEAR 15MPH BY LATE DAY.
TEMPS...EVENTUAL EXTENT OF STRATUS DECK BOTH IN COVERAGE AND TIME
WILL BE CRITICAL...AS THEY WERE ON MONDAY...ON DETERMINING HOW WARM
TEMPS GO OVER THE SOUTHEASTERN PORTIONS OF THE FORECAST AREA. WITH
WARM ADVECTION TODAY...LOW LEVEL THERMALS SUPPORTIVE OF MAX TEMPS IN
THE LOWER/MIDDLE 50S. GENERALLY NEAR MAVMOS GUIDANCE...ALTHOUGH DID
UNDERCUT MAV BY A FEW DEGREES OVER SOUTHERN COUNTIES WITH POTENTIAL
IMPACTS FROM CLOUDS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 336 AM EDT TUE MAR 18 2014
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TONIGHT/WEDNESDAY AND
AGAIN THURSDAY NIGHT WITH TWO SYSTEMS IMPACTING THE REGION.
LOW PRESSURE WILL PINWHEEL INTO THE GREAT LAKES WEDNESDAY AND SWING
A COLD FRONT ACROSS CENTRAL INDIANA DURING THE MORNING. MOISTURE
FETCH IS LIMITED OVERALL BUT FORCING THROUGH THE BOUNDARY LAYER AND
DIFFLUENCE ALOFT SHOULD BE MORE THAN SUFFICIENT FOR PRECIP TO
DEVELOP LATE TONIGHT INTO WEDNESDAY MORNING. STRENGTHENING LOW LEVEL
JET WILL ROTATE ACROSS CENTRAL INDIANA LATE TONIGHT AND PROMOTE A
BRIEF PERIOD WITH ISENTROPIC LIFT AHEAD OF THE FRONT AS WELL. WILL
CARRY LIKELY POPS OVER NORTHERN COUNTIES LATE TONIGHT AND WEDNESDAY
MORNING IN CLOSEST PROXIMITY TO BETTER FORCING AND DEEPER MOISTURE
WITH CHANCE POPS FURTHER SOUTH ACROSS THE FORECAST AREA. POTENTIAL
EXISTS FOR A CONVECTIVE COMPONENT TO PRECIP AND POTENTIALLY A FEW
RUMBLES OF THUNDER OVER THE NORTHERN WABASH VALLEY AS SOME ELEVATED
INSTABILITY WILL BE PRESENT.
BIG ISSUE WITH THE PASSAGE OF THE COLD FRONT WILL BE THE WINDS. THE
LOW LEVEL JET MOVING ACROSS THE REGION LATE TONIGHT WILL PROMOTE
GUSTS INCREASING TO 20-30MPH...BUT PRESENCE OF A BOUNDARY LAYER
INVERSION SHOULD LIMIT WHAT MAKES IT TO THE GROUND. AS COLD
ADVECTION TAKES HOLD ONCE THE FRONT GOES BY WEDNESDAY MORNING
HOWEVER...MODEL SOUNDINGS SHOW AN ENVIRONMENT CONDUCIVE FOR STRONGER
WINDS ALOFT BEING PULLED TO THE SURFACE AS STEEPENING LAPSE RATES
PROMOTE EXCELLENT LOW LEVEL MIXING. MAX GUSTS OF 35-40 MPH LIKELY
DURING THE AFTERNOON...AND MAY APPROACH WIND ADVISORY CRITERIA AS
WELL. WILL MAINTAIN LOW CHANCE POPS THROUGH THE AFTERNOON WITH
SUBTLE INSTABILITY PRESENT.
ANY PRECIP CHANCES WILL END BY WEDNESDAY NIGHT AS THE LOW LIFTS OUT
TO THE NORTHEAST AND IS REPLACED BY A SURFACE RIDGE. EXPECT DRY
CONDITIONS TO PERSIST INTO THURSDAY EVENING AS THE RIDGE PASSES
THROUGH THE OHIO VALLEY. A WARM FRONT WILL MOVE INTO THE REGION
THURSDAY NIGHT AIDED BY A 30-40KT LOW LEVEL JET. NICE AXIS OF LOW
LEVEL CONVERGENCE AND ISENTROPIC LIFT DEVELOPING AT THE NOSE OF THE
JET ACROSS THE NORTHERN HALF OF THE FORECAST AREA WILL SUPPORT SOME
RAIN SHOWER DEVELOPMENT ALONG THE WARM FRONT. MOST OF THE PRECIP
SHOULD MOVE NORTH OF THE FORECAST AREA WITH THE BOUNDARY BY 12Z
FRIDAY.
TEMPS...HIGHS EXPECTED BY MIDDAY WEDNESDAY WITH SLOWLY FALLING TEMPS
THEREAFTER WITHIN THE COLD ADVECTION. PREFERRED COLDER MAVMOS HIGHS.
MAVMOS WAS ALSO PREFERRED FOR THURSDAY AS TEMPS EXPECTED TO RECOVER
NICELY INTO THE 50S WITH WARM ADVECTION DEVELOPING IN ADVANCE OF THE
WARM FRONT LATE DAY. MOS GUIDANCE APPEARED REASONABLE FOR LOWS
THROUGHOUT THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
ISSUED AT 310 AM EDT TUE MAR 18 2014
MODELS CONTINUE TO SUGGEST A PROGRESSIVE PATTERN DURING THE LONG
TERM PORTION OF THE FORECAST...WITH A LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT FRIDAY INTO FRIDAY NIGHT...AND ANOTHER ONE
EARLY NEXT WEEK.
FIRST SYSTEM FRIDAY INTO FRIDAY NIGHT MAY BRING A FEW
THUNDERSTORMS AS K INDICES AS HIGH AS 30 PLUS INDICATE A HEALTHY
PREFRONTAL INSTABILITY AXIS FRIDAY EVENING. EARLY NEXT WEEK SYSTEM
IS MUCH MORE BORDERLINE TEMPERATURE WISE...AND WILL CARRY RAIN OR
SNOW FOR NOW.
TEMPERATURES WILL BEGIN QUITE WARM IN THE STRONG WARM ADVECTION
AHEAD OF THE FRONT...BEFORE BECOMING NEAR TO BELOW NORMAL OVER THE
WEEKEND. NEAR TO JUST BEYOND THE SEVEN DAY FORECAST
PERIOD...GUIDANCE SUGGESTS POTENTIAL FOR YET ANOTHER COLD
INTRUSION FROM THE WINTER THAT REFUSES TO END.
&&
.AVIATION /DISCUSSION FOR THE 18/06Z TAF ISSUANCE/...
ISSUED AT 1256 AM EDT TUE MAR 18 2014
LOW TO MEDIUM CONFIDENCE FORECAST. VFR WILL BECOME MVFR LATE TONIGHT
ACROSS EASTERN SITES. VFR SHOULD RETURN BY AFTERNOON...BUT MVFR
POSSIBLE LATE TUESDAY AFTERNOON.
SOME CLOUDS AROUND 3000FT REMAIN RELATIVELY CLOSE TO THE
SOUTHEAST...BUT EVEN LARGER CLOUD DECK FARTHER SOUTHEAST IS ALREADY
MOVING BACK NORTHWEST. ALSO...SHORT RANGE MODELS AND ENSEMBLES ARE
SHOWING MVFR DECK MOVING BACK IN TONIGHT.
THEREFORE HAVE ADDED A PERIOD OF MVFR CEILINGS LATE TONIGHT AT KIND
AND KBMG. NOT CONFIDENT ENOUGH YET TO ADD TO WESTERN SITES...BUT IT
IS STILL CERTAINLY POSSIBLE THAT DECK COULD SNEAK THAT FAR WEST.
CEILINGS AS LOW AS BKN010 NOT OUT OF THE QUESTION WITH THIS DECK.
CONFIDENCE IS STILL LOW TO MEDIUM.
NOT SURE ABOUT FOG DEVELOPMENT AS FORECAST SOUNDINGS INDICATE BETTER
CHANCES FOR STRATUS THAN FOG...BUT FOR NOW HAVE KEPT 6SM LATE
TONIGHT.
ANY LOWER CLOUDS SHOULD SCATTER OUT TUESDAY MORNING...BUT MOISTURE
MOVING IN AHEAD OF THE NEXT SYSTEM COULD BRING MVFR CEILINGS LATER
TUESDAY AFTERNOON AND TUESDAY EVENING. FOR NOW HAVE JUST PUT THEM AT
KBMG BEFORE 00Z WEDNESDAY AND LOW VFR ELSEWHERE AFTER 00Z.
WINDS WILL GUST TO AROUND 20KT AFTER 15Z TUESDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...50
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
527 AM EDT TUE MAR 18 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 434 AM EDT TUE MAR 18 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WNW FLOW ALF OVER
THE UPR LKS BTWN PERSISTENT MEAN TROF OVER QUEBEC AND RDG ALONG THE
W COAST. A VIGOROUS SHRTWV THAT TOPPED THE WRN RDG IS MOVING ESEWD
THRU THE CENTRAL ROCKIES...ACCOMPANIED BY 12Z-24Z H3 HGT FALLS UP TO
300M IN WYOMING. THERE HAVE EVEN BEEN A FEW LTG STRIKES IN THE COMMA
HEAD OF THE ACCOMPANYING CLD SHIELD OVER THE NRN ROCKIES INTO THE
NRN PLAINS. BAND OF ENHANCED CLD TO THE NE OF DVLPG SFC LO PRES IN
NEBRASKA EXTENDS NE INTO CNTRL MN/NW WI...CORRELATED BEST WITH AXIS
OF HIER H7-6 FGEN...BUT WELL N OF H85 WARM FNT STRETCHING FM SDAKOTA
THRU NRN IOWA. PCPN HAS HAD A HARD TIME DEVELOPING UNDER THE SHARPER
FGEN DUE TO RATHER DRY NATURE OF THE 00Z MPX RAOB...BUT SOME SN HAS
REACHED AS FAR NE AS HYR IN NW WI AS OF 09Z. ALTHOUGH SKIES ARE CLDY
OVER UPR MI...THERE IS CURRENTLY NO PCPN FALLING OVER THE CWA
DESPITE LARGER SCALE WAD AND PRESENCE OF WEAKER H85 WARM FNT
ASSOCIATED WITH SHRTWV TRACKING ACRS NRN LK SUP IN WNW FLOW ALF.
FEED OF LLVL DRY AIR SHOWN ON THE 00Z GRB RAOB IS LIKELY PLAYING A
ROLE. EVEN DEEPER DRIER AIR IS PRESENT S OF GRB.
MAIN FCST CONCERNS THRU TNGT WL FOCUS ON POPS/SN AMOUNTS AND NEED
FOR HEADLINES AS SHRTWV/ACCOMPANYING SFC LO OVER THE ROCKIES/PLAINS
MOVE TO THE E.
TODAY...AS S WINDS TO THE E OF DEEPENING LO PRES IN THE PLAINS
STRENGTHEN...BAND OF SHARPER H7-6 FGEN IS FCST TO SHIFT TO THE NE
INTO UPR MI. MORE DYNAMIC SUPPORT WL COME FM UPR DVGC IN RRQ OF H3
JET MAX FCST TO BE MOVING NEWD THRU ONTARIO. SINCE NEGATIVE H85
DEWPT ADVECTION ASSOCIATED WITH THE DRY AIR TO THE S WL BE IMPACTING
MAINLY THE E HALF OF THE CWA...ACCOMPANYING POPS WL BE HIER OVER THE
W. BUT EVEN THERE...MOST OF THE MODELS SHOW SOME DRYING WL ARRIVE
AND SHUNT THE PCPN OFF INTO NW LK SUP AS AXIS OF FGEN SHIFTS TO THE
NW AS WELL. THE NAM IS MOST AGGRESSIVE WITH THIS DRYING. AS FAR AS
SN AMOUNTS ARE CONCERNED...AXIS OF H7 SPECIFIC HUMIDITY UP TO 3 G/KG
IS FCST TO BE OVER THE AXIS OF SHARPER FGEN THIS MRNG. BUT INFLUX OF
DRIER LLVL AIR IS FCST TO DIMINISH THIS VALUE THRU THE DAY.
OVERALL...SUSPECT SN AMOUNTS WL APRCH ADVY CRITERIA OVER THE FAR W
WHERE THE FGEN IS PROGGED TO BE MOST PERSISTENT AND DRYING LESS
AGGRESSIVE. NARROW...RATHER HI...NARROW DGZ RESULTING IN SN/WATER
RATIOS IN THE 10-15:1 RANGE WL NOT HELP SN TOTALS.
TNGT...SHRTWV FM THE PLAINS IS FCST TO BECOME MORE NEGATIVELY TILTED
AS IT MOVES INTO WI BY 12Z WED. ALTHOUGH DEEP LYR QVECTOR CNVGC IN
THE DVPA/PERSISTENT ISENTROPIC ASCENT AHEAD OF THIS FEATURE IS FCST
TO OVERSPREAD THE CWA...THE SHARPER FORCING AND ACCOMPANYING H4-2
DVGC ARE PROGGED TO IMPACT THE SE HALF OF THE CWA...WHERE THE DRIER
AIR IS FCST TO BE DEEPEST. OUT OF SYNC NATURE OF THE FORCING/DEEPER
MSTR IS OF CONCERN AND WL LIKELY LIMIT SN TOTALS. IN FACT...MODEL
QPF VARIES SGNFTLY ACRS THE CWA. ADVY SN IS MOST LIKELY OVER THE W
HALF WHERE MSTR IS DEEPER AND SHARPENING CYC NNE FLOW LATER TNGT
MIGHT ENHANCE SN TOTALS A BIT. SINCE THERE IS LTL INTERACTION WITH
THE ARCTIC BRANCH IN CANADA...ANOTHER FACTOR THAT WL LIMIT
QPF...MODELS HAVE TRENDED A BIT FARTHER S WITH THE SFC LO TRACK...
INDICATING THE SFC LO WL REACH NO FARTHER N THAN ABOUT MILWAUKEE BY
12Z WED. THESE TRENDS SUG THE BULK OF THE PCPN WL BE IN THE FORM OF
SN. RETAINED A MENTION OF -FZRA OVER THE SE PER THE WARMER NAM
MODEL...WHICH SHOWS ELEVATED WARM LYR CENTERED AT 3K FT THRU THE NGT
NEAR LK MI. LATER SHIFTS MAY BE ABLE TO REMOVE THIS MENTION OF MIXED
PCPN IF CURRENT TRENDS PERSIST.
AS FOR HEADLINES...OPTED TO ISSUE AN ADVY FOR THE W TODAY GIVEN AXIS
OF SHARPER FGEN/LATER DRYING. EXPANDED THE ADVYS TO THE E TO COVER
THE ENTIRE CWA BY LATE TNGT TO REFLECT ARRIVAL OF SHARPER DYNAMICS/
HIER POPS THAT WL INFLUENCE THE AREA INTO WED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 524 AM EDT TUE MAR 18 2014
STRONG SOUTHERN STREAM SYSTEM CROSSES THE GREAT LAKES TO START THE
DAY ON WEDNESDAY. MODELS ARE SETTLING ON A SFC LOW AROUND DAYBREAK
ON WEDNESDAY NEAR MILWAUKEE WI...TRACKING INTO THE NORTHERN PART OF
LK HURON BY WEDNESDAY EVENING. UPPER LEVELS BECOME NEGATIVE TILTED
LATE TONIGHT INTO WEDNESDAY...BUT WITHOUT MUCH ADDITIONAL INTERACTION
FROM NORTHERN BRANCH SHORTWAVES/COLD AIR...SYSTEM IS LOOKING MORE
PROGRESSIVE THAN IT DID 24 HR AGO. THIS SHOWS UP SEEING THE FARTHER
SOUTH AND EAST SFC LOW /GEM-NH HAS SHOWN THIS FOR MULTIPLE RUNS/.
WARM LAYER NOT VERY MUCH OF A FACTOR NOW EITHER...PERHAPS REACHING
INTO FAR SE CWA FOR A VERY BRIEF TIME LATE TONIGHT THROUGH AROUND
DAYBREAK ON WEDNESDAY. PROGRESSIVE NATURE OF SYSTEM IS VERY APPARENT
BY LOOKING AT H85-H7 MOISTURE TRANSPORT...WHICH IS NOW MAXIMIZING
LATE TONIGHT INTO WEDNESDAY OVER THE CNTRL GREAT LAKES INSTEAD OF
INTO CNTRL UPR MICHIGAN. THUS...NOT AS MUCH MOISTURE FOR THE SYSTEM
TO WORK WITH AND H7 MIXING RATIOS ONLY TOP OUT BTWN 2.25 AND 2.5G/KG
COMPARED TO THE 3.0 OR HIGHER VALUES SHOWN PREVIOUSLY. USING THE
GARCIA METHOD THIS WOULD SUGGEST UP TO 5 INCHES OF SNOW IN A 12 HOUR
PERIOD AND THIS ESTIMATE IS ON PAR WHEN USING AN AVERAGE OF MODEL
TOTAL QPF BTWN 00Z WED AND 00Z THURSDAY ALONG WITH SLR/S AROUND 12:1
/LIMITED LIFT OCCURRING IN THE HIGH DGZ WELL ABOVE H7/.
OVERALL SEEMS LIKE FAR WEST CWA WILL SEE THE MOST SNOW FROM THIS
SYSTEM BY WEDNESDAY EVENING AS H7 FGEN THAT IMPACTS THAT AREA TODAY
MAY PROVIDE A FOCUS FOR ADDITIONAL SNOW LATER TONIGHT THROUGH MUCH
OF WEDNESDAY AS LARGER SCALE FORCING FM MAIN SHORTWAVE IMPACTS THE
AREA AS SHOWN BY SWATH OF MODERATE H85-H7/H7-H5 Q-VECTOR CONVERGENCE
AND PERSISTENT DIVERGENCE ALOFT WITHIN RIGHT ENTRANCE OF H3 JET OVER
NORTHERN ONTARIO AND QUEBEC. ADDITIONALLY...THERE ARE INDICATIONS
THAT SNOW TIED TO FGEN AREA WOULD BE ENHANCED OVER THE NORTHWEST
CWA VCNTY OF KEWEENAW AS PRESENCE OF FS CONVERGENCE SUGGESTS THE
SNOW BAND WILL PIVOT OVER THAT AREA AS IT LIFTS NORTH THEN MOVES
EAST /RESULTING IN MODERATE SNOW POSSIBLY PERSISTING INTO EARLY
WEDNESDAY EVENING/. FARTHER TO THE EAST OVER THE REST OF THE CWA
IT GETS TRICKY TO FIGURE HOW MUCH SNOW MAY OCCUR...ESPECICALLY OVER
THE CNTRL AS THAT AREA WOULD BE ON THE EASTERN SUBSIDENCE SIDE OF
THE FGEN OVER THE WEST AND NORTHWEST CWA. H7 FGEN DOES INCREASE
ACROSS CNTRL AND EASTERN CWA ON WEDNESDAY AS THE LARGER SCALE
FORCING IMPACTS THE AREA BUT WITH THE MINIMAL MOISTURE ADVECTION
WORKING INTO THE SYSTEM...QPF/SNOW AMOUNTS DO NOT LOOK TO GET OUT OF
HAND. ADVY SNOW AMOUNTS SEEM REASONABLE LATER TONIGHT THROUGH
WEDNESDAY.
HEADLINES...AFTER COORD WITH SHORT TERM FORECASTER AND SURROUNDING
OFFICES DECIDED ON AN ADVY FOR ENTIRE CWA. GIVEN UNCERTAINTY ON
WHERE STRONGER FGEN SNOW BAND REDEVELOPS TONIGHT INTO WEDNESDAY WILL
LET LATER SHIFTS ASSESS WHETHER UPGRADE TO WARNING IS NEEDED FOR ANY
PARTS OF CWA. START TIMES FOR ADVY VARY WITH FAR WEST BEGINNING
TODAY AND REST OF CWA COMING INTO THE ADVY LATER THIS EVENING AND
OVERNIGHT TONIGHT. RAN THE ADVY THROUGH EARLY WEDNESDAY EVENING MOST
AREAS...BUT DID PUSH IT THROUGH MIDNIGHT WEDNESDAY NIGHT OVER
NORTHEAST CWA WITH SNOW LINGERING ON BACK SIDE OF THE LOW PRESSURE
AND ALSO WITH GUSTY NW WINDS LEADING TO BLSN CLOSER TO LK SUPERIOR.
THURSDAY AND THURSDAY NIGHT...COULD SEE LINGERING LIGHT SNOW SHOWERS
NEAR LK SUPERIOR ON THURSDAY IN WAKE OF THE SYSTEM. ECMWF/GFS INDICATE
MOISTURE THROUGH H9 WITH H9 TEMPS AROUND -10C. SLIGHT CHANCES WILL
COVER THIS POTENTIAL. HIGH PRESSURE RIDGE CROSSES THURSDAY NIGHT AND
DOES NOT APPEAR THAT MID-HIGH CLOUDS WILL ARRIVE AHEAD OF NEXT SYSTEM
UNTIL LATE THURSDAY NIGHT OVER THE WEST. TEMPS MAY DIVE TOWARD ZERO
OR EVEN BLO OVER INTERIOR SECTIONS WITH THE FRESH SNOW COVER AND CALM
CONDITIONS. NW WINDS BLO H9 MAY KEEP TEMPS SLIGHTLY WARMER NEAR LK
SUPERIOR.
REST OF EXTENDED...GFS STILL FARTHER NORTH COMPARED TO ECMWF AND
GEM-NH WITH SHORTWAVE/SFC TROUGH SLIDING ACROSS WESTERN GREAT LAKES
FRIDAY INTO FRIDAY EVENING. SLIGHT CHANCES FOR MOST AREAS...BUT HAVE
A BIT HIGHER ALONG WISCONSIN BORDER. COLD FRONT WORKS THROUGH LATER
FRIDAY NIGHT INTO SATURDAY AS NORTHERN STREAM WAVE DROPS THROUGH.
ENOUGH MID LEVEL MOISTURE TIED TO THE WAVE/COLD FRONT TO HAVE SOME
SMALLER CHANCES IN FOR MAINLY NORTH HALF OF CWA. WITH H85 TEMPS
DROPPING BLO -20C ON SATURDAY AND WITH LINGERING FORCING STILL
AROUND...LIKED PREVIOUS SHIFTS LIKELY POPS FOR NW AND NCNTRL CWA ON
SATURDAY FOR POTENTIAL OF LAKE ENHANCED SNOW SHOWERS. LARGE HIGH
PRESSURE BUILDS IN FOR SUNDAY LEADING TO DRY AND VERY CHILLY WEATHER.
HIGH TEMPS ON SUNDAY FORECAST TO BE IN THE TEENS TO MID 20S...WHICH
WOULD END UP CLOSE TO 20 DEGREES BLO NORMAL FOR THIS TIME OF YEAR. &&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 121 AM EDT TUE MAR 18 2014
KIWD AND KCMX...WILL SEE GENERALLY MVFR CONDITIONS UNTIL LATE
TONIGHT/TUE MORNING WHEN THE NEXT SNOW BAND MOVES ACROSS THE AREA
ALONG AN INVERTED SFC TROUGH FROM A LOW PRESSURE SYSTEM MOVING
THROUGH THE CENTRAL PLAINS. WHEN SNOW BAND LIFTS NORTH...EXPECT SOME
IMPROVEMENT TUE AFTERNOON. YET ANOTHER SNOW BAND WILL BRING LOW MVFR
TO IFR CONDITIONS BY LATE TUE EVENING.
KSAW...EXPECT IFR CONDITIONS TO IMPROVE BRIEFLY TO MVFR OVERNIGHT
BEFORE THE NEXT SNOW BAND MOVES THROUGH THE AREA AROUND 12Z.
CONDITIONS COULD AGAIN LOWER TO NEAR IFR AROUND 12Z BUT THEN IMPROVE
ONCE AGAIN IN THE AFTERNOON AS THE SNOW BAND LIFTS NORTH. EXPECT
CONDITIONS TO LOWER AGAIN TOWARD IFR TUE EVENING AS ANOTHER BAND OF
SNOW APPROACHES FROM THE SW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 524 AM EDT TUE MAR 18 2014
E-SE WINDS UP 20 KTS THIS MORNING WILL BACK TO THE N-NE AND INCREASE
TO UP TO 25-30 KTS BY WED AS A LO PRES IN THE PLAINS MOVES TO THE
LOWER GREAT LAKES. THE PASSAGE OF A HI PRES RIDGE/FLATTER PRES
GRADIENT IN ITS WAKE WILL RESULT IN DIMINISHING AND BACKING WINDS TO
THE S INTO FRI. AFTER ANOTHER LOW SHIFTS TO THE EAST THROUGH THE
LOWER GREAT LAKES ON FRI AND ANOTHER CANADIAN HIGH PRESSURE BUILDS
INTO THE NORTHERN PLAINS...A STRONGER N-NW WIND UP TO 25-30 KTS WILL
DEVELOP LATE FRI INTO SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 2 AM WEDNESDAY TO MIDNIGHT EDT
WEDNESDAY NIGHT FOR MIZ006-007-085.
WINTER WEATHER ADVISORY FROM 11 PM EDT /10 PM CDT/ THIS EVENING
TO 8 PM EDT /7 PM CDT/ WEDNESDAY FOR MIZ004-005-010-011-084.
WINTER WEATHER ADVISORY UNTIL 8 PM EDT /7 PM CDT/ WEDNESDAY FOR
MIZ001>003-009.
WINTER WEATHER ADVISORY FROM 2 AM EDT /1 AM CDT/ TO 8 PM EDT /7
PM CDT/ WEDNESDAY FOR MIZ012>014.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
436 AM EDT TUE MAR 18 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 434 AM EDT TUE MAR 18 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WNW FLOW ALF OVER
THE UPR LKS BTWN PERSISTENT MEAN TROF OVER QUEBEC AND RDG ALONG THE
W COAST. A VIGOROUS SHRTWV THAT TOPPED THE WRN RDG IS MOVING ESEWD
THRU THE CENTRAL ROCKIES...ACCOMPANIED BY 12Z-24Z H3 HGT FALLS UP TO
300M IN WYOMING. THERE HAVE EVEN BEEN A FEW LTG STRIKES IN THE COMMA
HEAD OF THE ACCOMPANYING CLD SHIELD OVER THE NRN ROCKIES INTO THE
NRN PLAINS. BAND OF ENHANCED CLD TO THE NE OF DVLPG SFC LO PRES IN
NEBRASKA EXTENDS NE INTO CNTRL MN/NW WI...CORRELATED BEST WITH AXIS
OF HIER H7-6 FGEN...BUT WELL N OF H85 WARM FNT STRETCHING FM SDAKOTA
THRU NRN IOWA. PCPN HAS HAD A HARD TIME DEVELOPING UNDER THE SHARPER
FGEN DUE TO RATHER DRY NATURE OF THE 00Z MPX RAOB...BUT SOME SN HAS
REACHED AS FAR NE AS HYR IN NW WI AS OF 09Z. ALTHOUGH SKIES ARE CLDY
OVER UPR MI...THERE IS CURRENTLY NO PCPN FALLING OVER THE CWA
DESPITE LARGER SCALE WAD AND PRESENCE OF WEAKER H85 WARM FNT
ASSOCIATED WITH SHRTWV TRACKING ACRS NRN LK SUP IN WNW FLOW ALF.
FEED OF LLVL DRY AIR SHOWN ON THE 00Z GRB RAOB IS LIKELY PLAYING A
ROLE. EVEN DEEPER DRIER AIR IS PRESENT S OF GRB.
MAIN FCST CONCERNS THRU TNGT WL FOCUS ON POPS/SN AMOUNTS AND NEED
FOR HEADLINES AS SHRTWV/ACCOMPANYING SFC LO OVER THE ROCKIES/PLAINS
MOVE TO THE E.
TODAY...AS S WINDS TO THE E OF DEEPENING LO PRES IN THE PLAINS
STRENGTHEN...BAND OF SHARPER H7-6 FGEN IS FCST TO SHIFT TO THE NE
INTO UPR MI. MORE DYNAMIC SUPPORT WL COME FM UPR DVGC IN RRQ OF H3
JET MAX FCST TO BE MOVING NEWD THRU ONTARIO. SINCE NEGATIVE H85
DEWPT ADVECTION ASSOCIATED WITH THE DRY AIR TO THE S WL BE IMPACTING
MAINLY THE E HALF OF THE CWA...ACCOMPANYING POPS WL BE HIER OVER THE
W. BUT EVEN THERE...MOST OF THE MODELS SHOW SOME DRYING WL ARRIVE
AND SHUNT THE PCPN OFF INTO NW LK SUP AS AXIS OF FGEN SHIFTS TO THE
NW AS WELL. THE NAM IS MOST AGGRESSIVE WITH THIS DRYING. AS FAR AS
SN AMOUNTS ARE CONCERNED...AXIS OF H7 SPECIFIC HUMIDITY UP TO 3 G/KG
IS FCST TO BE OVER THE AXIS OF SHARPER FGEN THIS MRNG. BUT INFLUX OF
DRIER LLVL AIR IS FCST TO DIMINISH THIS VALUE THRU THE DAY.
OVERALL...SUSPECT SN AMOUNTS WL APRCH ADVY CRITERIA OVER THE FAR W
WHERE THE FGEN IS PROGGED TO BE MOST PERSISTENT AND DRYING LESS
AGGRESSIVE. NARROW...RATHER HI...NARROW DGZ RESULTING IN SN/WATER
RATIOS IN THE 10-15:1 RANGE WL NOT HELP SN TOTALS.
TNGT...SHRTWV FM THE PLAINS IS FCST TO BECOME MORE NEGATIVELY TILTED
AS IT MOVES INTO WI BY 12Z WED. ALTHOUGH DEEP LYR QVECTOR CNVGC IN
THE DVPA/PERSISTENT ISENTROPIC ASCENT AHEAD OF THIS FEATURE IS FCST
TO OVERSPREAD THE CWA...THE SHARPER FORCING AND ACCOMPANYING H4-2
DVGC ARE PROGGED TO IMPACT THE SE HALF OF THE CWA...WHERE THE DRIER
AIR IS FCST TO BE DEEPEST. OUT OF SYNC NATURE OF THE FORCING/DEEPER
MSTR IS OF CONCERN AND WL LIKELY LIMIT SN TOTALS. IN FACT...MODEL
QPF VARIES SGNFTLY ACRS THE CWA. ADVY SN IS MOST LIKELY OVER THE W
HALF WHERE MSTR IS DEEPER AND SHARPENING CYC NNE FLOW LATER TNGT
MIGHT ENHANCE SN TOTALS A BIT. SINCE THERE IS LTL INTERACTION WITH
THE ARCTIC BRANCH IN CANADA...ANOTHER FACTOR THAT WL LIMIT
QPF...MODELS HAVE TRENDED A BIT FARTHER S WITH THE SFC LO TRACK...
INDICATING THE SFC LO WL REACH NO FARTHER N THAN ABOUT MILWAUKEE BY
12Z WED. THESE TRENDS SUG THE BULK OF THE PCPN WL BE IN THE FORM OF
SN. RETAINED A MENTION OF -FZRA OVER THE SE PER THE WARMER NAM
MODEL...WHICH SHOWS ELEVATED WARM LYR CENTERED AT 3K FT THRU THE NGT
NEAR LK MI. LATER SHIFTS MAY BE ABLE TO REMOVE THIS MENTION OF MIXED
PCPN IF CURRENT TRENDS PERSIST.
AS FOR HEADLINES...OPTED TO ISSUE AN ADVY FOR THE W TODAY GIVEN AXIS
OF SHARPER FGEN/LATER DRYING. EXPANDED THE ADVYS TO THE E TO COVER
THE ENTIRE CWA BY LATE TNGT TO REFLECT ARRIVAL OF SHARPER DYNAMICS/
HIER POPS THAT WL INFLUENCE THE AREA INTO WED.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 439 PM EDT MON MAR 17 2014
THE 12Z RUNS HAVE BECOME MUCH MORE IN LINE WITH THE TRACK OF THE SFC
LOW OVER N MO/FAR S IA AT 00Z...TO GRB-MKE BY 12Z...NEAR THE
MACKINAC BRIDGE AND N LOWER MI BY 18Z...AND E OF DRUMMOND ISLAND BY
00Z THURSDAY. THE NAM CONTINUES TO BE A BIT ON ITS OWN...SLIGHTLY W
OF MODEL CONSENSUS. WILL RELY MORE HEAVILY ON THE NON-NAM SOLUTIONS
FOR THIS PERIOD.
POCKET OF WARM AIR WILL SURGE IN NEAR LAKE MI TUESDAY NIGHT INTO MID
DAY WEDNESDAY. SNOWFALL AMOUNTS ON THE ORDER OF 3 TO 7 INCHES WILL
BE POSSIBLE ACROSS MUCH OF WESTERN AND CENTRAL UPPER MICHIGAN...WITH
SLIGHTLY HIGHER AMOUNTS OVER FAR WESTERN UPPER MICHIGAN. CONTINUED
THE WINTER STORM WATCH FOR THE TONIGHT THROUGH WEDNESDAY TIME
PERIOD...WITH THE BEST CHANCE OF UPSLOPE/LAKE ENHANCED PRECIP OVER W
UPPER MI WEDNESDAY AFTERNOON. GOOD MOISTURE IN THE DGZ /GENERALLY
600-700MB/ ALIGNING WITH OMEGA. WILL NEED TO WAIT ANOTHER ROUND TO
SEE IF THE W HALF WILL NEED TO BE BROUGHT UP TO WARNING
CRITERIA...OR IF MUCH OF W AND CENTRAL UPPER MI WOULD BE BETTER
SERVED UNDER A WINTER WX ADVISORY. CONTINUED THE SPS FOR NON-WATCH
LOCATIONS. BEHIND THE LOW WE WILL HAVE STEADY NW WINDS WEDNESDAY
NIGHT...WITH GUSTS JUST OFF SHORE ON THE ORDER OF 25 TO 35KTS.
EXPECT QUICKLY DIMINISHING WINDS THURSDAY AS THE SFC RIDGE OVER E MN
AT 12Z PUSHES ACROSS UPPER MI/LAKE SUPERIOR THROUGH THE DAY. OUT TO
OUR W THE NEXT LOW STRETCHED FROM THE MT/ND/SASKATCHEWAN BORDER AT
18Z THURSDAY WILL SINK SE TO S MN AND IA BY DAYBREAK FRIDAY.
THE SFC LOW STILL LOOKS TO CLIP S LAKE MI BY 00Z SATURDAY /WITH THE
17/00Z RUN OF THE ECMWF EVEN FARTHER TO THE S/. WHILE THE MAIN
IMPACTS FROM THE SFC LOW WILL REMAIN TO OUR S...THE 500MB PATTERN
DOES SHOW A SIGNIFICANT SHORTWAVE SINKING ACROSS THE UPPER GREAT
LAKES. 850MB TEMPS OF -4 TO -6C AT 0Z SATURDAY WILL QUICKLY FALL
BEHIND THE EXIT OF THE SFC LOW...WITH INCREASING N-NW BRINGING 850MB
TEMPS DOWN TO -15 TO -20C BY 8Z SATURDAY. DEPENDING ON HOW MUCH ICE
IS LEFT ACROSS LAKE SUPERIOR...LIGHT TO MODERATE LES WILL BE
POSSIBLE FOR A SHORT PERIOD. THE MAIN PROBLEM WILL BE THE LOSS OF
THE DGZ LATE SATURDAY AFTERNOON INTO SUNDAY MORNING. SNOW WILL STILL
BE POSSIBLE...BUT DRIER HIGH PRESSURE SLIDING IN FROM THE N PLAINS
SUNDAY MORNING WILL MOVE OVERHEAD THROUGH SUNDAY NIGHT. A COLD
WEEKEND WILL BE THE RESULT...WITH HIGHS SATURDAY IN THE 20S AND ON
SUNDAY IN THE TEENS FOR THE MOST PART.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 121 AM EDT TUE MAR 18 2014
KIWD AND KCMX...WILL SEE GENERALLY MVFR CONDITIONS UNTIL LATE
TONIGHT/TUE MORNING WHEN THE NEXT SNOW BAND MOVES ACROSS THE AREA
ALONG AN INVERTED SFC TROUGH FROM A LOW PRESSURE SYSTEM MOVING
THROUGH THE CENTRAL PLAINS. WHEN SNOW BAND LIFTS NORTH...EXPECT SOME
IMPROVEMENT TUE AFTERNOON. YET ANOTHER SNOW BAND WILL BRING LOW MVFR
TO IFR CONDITIONS BY LATE TUE EVENING.
KSAW...EXPECT IFR CONDITIONS TO IMPROVE BRIEFLY TO MVFR OVERNIGHT
BEFORE THE NEXT SNOW BAND MOVES THROUGH THE AREA AROUND 12Z.
CONDITIONS COULD AGAIN LOWER TO NEAR IFR AROUND 12Z BUT THEN IMPROVE
ONCE AGAIN IN THE AFTERNOON AS THE SNOW BAND LIFTS NORTH. EXPECT
CONDITIONS TO LOWER AGAIN TOWARD IFR TUE EVENING AS ANOTHER BAND OF
SNOW APPROACHES FROM THE SW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 PM EDT MON MAR 17 2014
S WINDS UP TO 25-30KT THIS AFTERNOON HAVE RESULTED UNDER SHARPENING
PRESSURE GRADIENT BETWEEN SLOWLY DEPARTING HIGH PRESSURE AND
DEVELOPING LOW PRESSURE TO THE W IN THE PLAINS. AS THIS LOW MOVES
TOWARD THE UPPER GREAT LAKES ON TUE INTO WED...LIKELY PASSING JUST
TO THE S OF UPPER MI...THE FLOW WILL BACK TO THE E AND THEN N BY
WED...WITH WINDS INCREASING UP TO 30 KTS ON WED. THE STRONG WINDS
WILL DIMINISH STEADILY THROUGH THU AS A TRAILING HIGH PRESSURE RIDGE
MOVES INTO THE UPPER LAKES. A STRONGER N WIND UP TO 25-30KT MAY
DEVELOP ON FRI AS A LOW PRESSURE SYSTEM PASSES TO THE S THROUGH THE
LOWER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 2 AM WEDNESDAY TO MIDNIGHT EDT
WEDNESDAY NIGHT FOR MIZ006-007-085.
WINTER WEATHER ADVISORY FROM 11 PM EDT /10 PM CDT/ THIS EVENING
TO 8 PM EDT /7 PM CDT/ WEDNESDAY FOR MIZ004-005-010-011-084.
WINTER WEATHER ADVISORY FROM 8 AM EDT /7 AM CDT/ THIS MORNING TO
8 PM EDT /7 PM CDT/ WEDNESDAY FOR MIZ001>003-009.
WINTER WEATHER ADVISORY FROM 2 AM EDT /1 AM CDT/ TO 8 PM EDT /7
PM CDT/ WEDNESDAY FOR MIZ012>014.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...VOSS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
356 AM CDT TUE MAR 18 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT TUE MAR 18 2014
THE MODELS APPEAR TO BE SHOWING A HIGH DEGREE OF UNPREDICTABILITY
WITH THE STORM BEARING DOWN ON WRN AND NCNTL NEB THIS MORNING.
SEVERAL HIGHWAYS INCLUDING PARTS OF I-90/I-80 IN WYOMING NEAR
SHERIDAN...CASPER...LARAMIE AND CHEYENNE ARE CLOSED AND THE NUMBER
OF CLOSURES HAS BEEN RAPIDLY INCREASING SINCE MIDNIGHT. THE RAP13
AND 06Z NAM ARE HAMMERING SCNTL NEB WITH TROWAL AND THE RAP40 SHOWS
STRONG PETTERSON FGEN AT BOTH H850-700MB AND H700-500MB SUGGESTING
DEEP MOISTURE POOLING AND THE FORMATION OF A BARRIER JET ASSOCIATED
WITH 50KT-60KT WINDS BELOW 700MB. BOTH THE NAM AND RAP13 INDICATE
0.75 INCHES OF QPF DEVELOPING AS THIS BAND SETS UP THIS MORNING
ACROSS SCNTL NEB. THUS IN CONJUNCTION WITH THE ECM...IT WOULD APPEAR
THE HEAVY SNOW ACROSS WY WILL TRANSLATE EAST THRU WRN AND SCNTL NEB
TODAY. A WINTER WINTER WEATHER ADVISORY REPLACES THE WIND ADVISORY
IN ALL AREAS EXCEPT CUSTER AND FRONTIER COUNTY WHERE TEMPERATURES
ARE EXPECTED TO BE IN THE MID AND UPPER 30S TODAY. THE SUPER
ENSEMBLE TEMPERATURE FORECAST CLUSTERS NORTH PLATTE IN THE LOW TO
MID 30S LATE THIS MORNING AND THIS AFTERNOON.
THE ECM...NAM AND RAP13 WERE USED FOR THE QPF FORECAST WITH A 7 TO 1
SNOW RATIO FOR AROUND 3 INCHES OF SNOW CENTERED OVER LINCOLN COUNTY
NORTH AND SOUTH ALONG HIGHWAY 83. THE MODELS WILL LIKELY MOVE THIS
CENTER AROUND TODAY PERHAPS FARTHER WEST OR EAST OR EVEN SOUTH
DEPENDING ON HOW THE DYNAMICS COME TOGETHER. AT 08Z THE SFC LOW WAS
CENTERED OVER THE OKLAHOMA PANHANDLE AT 990 MB AND IS FORECAST TO
LIFT SLOWLY NORTHEAST TODAY AT AROUND 14KT. THIS SUPPORTS WIND
ADVISORY CONDITIONS WITH GUSTS TO 50 TO 55 MPH. GIVEN THE COMPACT
NATURE OF THE STORM AND THE RELATIVELY FAST MOTION...A PERIOD OF
HARSH WINTER WEATHER SHOULD DEVELOP LASTING 4 TO 8 HOURS. THE HRRR
INDICATES VISIBILITY FALLING TO 1/2 MILE. THE RAP AND NAM INDICATE
PCPN RATES NEAR OR ABOVE 0.10 INCH PER HOUR WHICH IS MODERATE TO
PERHAPS HEAVY SNOW.
THE SNOW SHOULD EXIT THE FORECAST AREA EARLY THIS EVENING THE SFC
LOW SHOULD OVER NRN IL BY WEDNESDAY MORNING. WINDS THIS EVENING
SHOULD DIMINISH AS SKIES CLEAR AND DECOUPLING OCCURS. LOWS TONIGHT
FALL INTO THE 20S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 354 AM CDT TUE MAR 18 2014
GENERAL NORTHWEST FLOW ALOFT CONTINUES UNCHANGED THROUGH THE PERIOD.
SEVERAL UPPER LEVEL DISTURBANCES WILL BE EMBEDDED WITHIN THE FLOW.
DUE TO CONTINUED LIMITED MOISTURE AND THE WEAK NATURE OF THE
SYSTEMS...I AM HESITANT TO INTRODUCE MUCH IN THE WAY OF POPS INTO
THE FORECAST. APPEARS SATURDAY WILL BE THE BEST SHOT FOR US TO
RECEIVE SOME LIGHT PRECIP...AND HAVE INTRODUCED A SLIGHT CHANCE FOR
RAIN OR SNOW SHOWERS.
TEMPERATURE WISE...THE WARMEST DAY WILL BE THURSDAY...AS A THERMAL
RIDGE QUICKLY BUILDS ACROSS THE AREA AHEAD OF A COLD FRONT SET TO
ARRIVE FRIDAY. HIGH PRESSURE...ORIGINATING FROM THE ARCTIC...WILL
BUILD SOUTH INTO THE NORTHERN PLAINS BEHIND THE FRONT DURING THE
WEEKEND...KEEPING TEMPERATURES BELOW NORMAL. A REINFORCING ARCTIC
HIGH PRESSURE CENTER BUILDS SOUTH INTO THE PLAINS EARLY NEXT
WEEK...WITH CONTINUED BELOW NORMAL TEMPERATURES. IN FACT...THE
LATEST RUN OF THE ECMWF MODEL INDICATES 850MB TEMPERATURES OF -10C
TO -15C BY WEDNESDAY MORNING ACROSS THE AREA. LONG STORY
SHORT...WINTER WILL CONTINUE TO HOLD IT/S GRIP DESPITE THE OFFICIAL
ARRIVAL OF SPRING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1203 AM CDT TUE MAR 18 2014
AS A STORM SYSTEM MAKES ITS WAY ACROSS NORTHERN NEBRASKA...A FRONT
WILL PLUNGE THROUGH TONIGHT AND EARLY TUESDAY. AS IT DOES...VERY
WINDY CONDITIONS WILL DEVELOP ALONG WITH LIGHT SNOW. IN THE CLOUDS
AND PRECIPITATION...VISIBILITY OF 1-3SM IS LIKELY ALONG WITH
CEILINGS AT OR BELOW 1000 FEET AGL. VISIBILITY IS EXPECTED TO BE
ABOVE VISUAL THRESHOLDS IN NORTHERN NEBRASKA BETWEEN 18Z AND 21Z...
BUT CEILING BELOW 1000 FEET AGL IS LIKELY UNTIL 22Z. IN SOUTHERN
NEBRASKA...VISIBILITY WILL BE AT OR ABOVE 3SM AROUND 21Z AND CEILING
ABOVE 1000 FEET AGL BY 00Z. THE 1000-2000 FT CEILING IS LIKELY TO
CONTINUE IN SOUTHWEST NEBRASKA UNTIL AFTER 03Z.
WIND 330-360 WILL INCREASE TO 20-25G30-36KT BY 13Z AND DECREASE TO
15-20G25-30 BY 02Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 10 AM CDT /9 AM MDT/ THIS MORNING
TO 7 PM CDT /6 PM MDT/ THIS EVENING FOR NEZ056>059-069-070.
WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING
FOR NEZ004>010-022>029-035>037-094.
WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING
FOR NEZ038-071.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
132 AM CDT TUE MAR 18 2014
.SYNOPSIS...
ISSUED AT 405 PM CDT MON MAR 17 2014
AT H5 CLOSED LOW OVER CENTRAL GULF OF MEXICO WITH ASSOCIATED TROUGH
THROUGH THE EASTERN SEABOARD. WAVE OVER MONTANA AND RIDGE OVER THE
EASTERN PACIFIC. AT THE SURFACE 989MB SURFACE LOW OVER THE EASTERN
PLAINS OF WYOMING.
&&
.UPDATE...
ISSUED AT 131 AM CDT TUE MAR 18 2014
A NEW FORECAST IS OUT USING THE RAP...SREF AND THE ENSEMBLE
APPROACH TO TEMPERATURES...PRECIPITATION AND THE PTYPE. CONSHORT
AND THE 13 MODEL ENSEMBLE IS UNIVERSAL SHOWING TEMPS IN THE MID TO
UPPER 30S TODAY WHICH WOULD SUPPORT SNOW AS A BAND OF STRONGLY
FORCED PCPN DEVELOPS THIS MORNING IN THE NORTHWEST WHICH
PROPAGATES EAST DURING THE DAY AND EXITS THE FORECAST AREA THIS
EVENING. THE PETERSEN FGEN IN THE RAP40 IS VERY STRONG AT
850-700MB AND 700-500MB WHICH WOULD SUPPORT DEEP SATURATION IN THE
AREA OF MODERATE PCPN THAT IS BELIEVED WILL FORM SHORTLY ACROSS
SHERIDAN COUNTY. WET RATES NEAR 0.10 INCHES ARE SHOWN IN THE RAP.
THE SNOW FORECAST IS MODEST USING AN 8 TO 1 RATIO. YESTERDAYS
HIGHS IN 70S WILL BE REPLACED BY WIND CHILL READINGS IN THE UPPER
TEENS AND 20S AND NOTE THAT 12 OF THE 13 MODELS AVAILABLE FOR QPF
SHOW OVER 0.15 INCHES OF LIQUID AT KLBF SO CONFIDENCE IS GOOD THAT
RAIN AND SNOW WILL FALL FOR DEFINITE POPS BUT THE OVERALL LIQUID
TOTAL WOULD LIKELY BE AROUND 1/4 INCH OR LESS. THIS PRODUCED SNOW
TOTALS UP TO 3 INCHES ACROSS NRN NEB.
THE NEW FORECAST BEEFS UP WIND GUSTS TO 50 TO 55 MPH. THIS IS
CLOSE TO THE NAMDNG5...GRIDDED MOS AND THE RAP MODELS.
UPDATE ISSUED AT 951 PM CDT MON MAR 17 2014
THE LATEST SHORT TERM PROJECTIONS INDICATE THAT PHASE CHANGE TO
SNOW MAY OCCUR EARLIER THAN ORIGINALLY FORECAST. BECAUSE OF THE
WARM SURFACES...IT IS DIFFICULT TO ESTIMATE THE ACTUAL SNOW
ACCUMULATION AS MUCH WILL PROBABLY BE LOST TO MELTING. THE
FORECAST WILL BE UPDATED TO REFLECT CURRENT THINKING.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 405 PM CDT MON MAR 17 2014
FORECAST FOCUS IS ON STORM SYSTEM TO MOVE ACROSS THE AREA THROUGH
TUESDAY. A STRONG SHORTWAVE TROUGH WAS OVER THE NORTHERN ROCKIES
THIS AFTERNOON WITH A STRONG THERMAL RIDGE OVER THE CENTRAL PLAINS.
THE SHORTWAVE WILL MAKE ITS WAY INTO THE CENTRAL PLAINS OVER THE
NEXT 24 HOURS AND WILL INTENSIFY IN THE PROCESS. THE UPPER LOW IS
BEING MODELED TO BE OVER EASTERN WYOMING AT 06Z TONIGHT...NORTHWEST
KANSAS/SOUTHWEST NEBRASKA AT 18Z...AND TO NORTHEAST KANSAS/SOUTHEAST
NEBRASKA AT 00Z. AS THE SHORTWAVE MOVES ACROSS THE AREA...IT WILL
PUSH A POTENT COLD FRONT THROUGH THE FORECAST AREA...WITH IT PASSING
ALL AREAS BY 15Z TUESDAY MORNING. BEHIND THE FRONT MOISTURE WILL BE
ON THE INCREASE...BRINGING PRECIPITATION INTO THE AREA NORTHWEST TO
SOUTHEAST. WITH THE AMOUNT OF MOISTURE THE MODELS ARE BRINGING INTO
THE REGION...AND WITH AMPLE LIFT WITH THE INCOMING SHORTWAVE
TROUGH...CONFIDENCE IS QUITE HIGH FOR PRECIPITATION ACROSS MOST OF
THE FORECAST AREA LATE TONIGHT AND TUESDAY.
WITH THE AIRMASS OVER THE AREA CURRENTLY BEING EXTREMELY DRY...IT
WILL TAKE SOME TIME TO GET THE COLUMN SATURATED SO BACKED OFF ON THE
TIMING OF THE PRECIPITATION ONSET. FORECAST SOUNDINGS AND CROSS
SECTIONS SHOW PRECIPITATION CHANCES INCREASE OVER THE NORTHERN
PANHANDLE AFTER 03Z...WITH HIGHER CONFIDENCE AFTER 06Z. THE BETTER
LIFT/MOISTURE/AND AREA OF MID LEVEL FRONTOGENESIS PROGRESSES
EASTWARD THROUGH TONIGHT AND TOMORROW...AS WILL THE HIGHER
PRECIPITATION CHANCES...WHICH WILL COME TO AN END FROM WEST TO EAST
LATE TUESDAY. WARM TEMPERATURES WILL ALLOW PRECIPITATION TO BEGIN AS
RAIN. BUT STRONG COLD AIR ADVECTION WILL QUICKLY COOL THE COLUMN AND
LOOKING AT THE WET BULB TEMPERATURE PROFILE...EXPECT A FEW HOURS OF
RAIN...PERHAPS AN HOUR OF A RAIN/SNOW MIX...THEN A QUICK CHANGEOVER
TO SNOW. BY AFTERNOON TUESDAY...WHERE THE MORE INTENSE SNOW HAS COME
TO AN END...SURFACE TEMPERATURES MAY WARM ENOUGH TO CHANGE THE SNOW
BACK TO RAIN. SNOW AMOUNTS ARE NOT EXPECTED TO BE MUCH...DESPITE
LIQUID AMOUNTS UP TO A QUARTER INCH. EVEN IF 4 INCHES OF SNOW WOULD
FALL...WARM GROUND TEMPERATURES WOULD KEEP MUCH FROM ACCUMULATING.
THE HIGHER SNOWFALL AMOUNTS IS CURRENTLY LOOKING TO BE NORTH OF A
LINE FROM OSHKOSH TO TRYON TO BARTLETT.
WINDS WILL BE QUITE INTENSE BEHIND THE SYSTEM AS A VERY STRONG
PRESSURE GRADIENT WILL BE PRESENT. 3 HR PRESSURE RISES OF 5 TO 8 MB
ARE BEING SHOWN BY THE MODELS SO STRONG PRESSURE GRADIENT WINDS WILL
BE ONGOING THROUGH THE DAY. ALSO...WINDS ABOVE THE SURFACE BEING
VERY STRONG /3K FT WINDS OF 65KTS/...ANY MIXING WILL LEAD TO INTENSE
WINDS. AT THIS TIME...LOOKS LIKE WINDS WILL BE AT HIGH END ADVISORY
LEVEL SO ISSUED A WIND ADVISORY FOR THE SOUTHERN PARTS OF THE
FORECAST AREA. THE WINDS WILL BE JUST AS STRONG FOR THE REMAINDER OF
THE FORECAST AREA...BUT WITH MORE SNOW EXPECTED IN THOSE
LOCATIONS...FELT THERE MAY BE SOME TRAVEL HAZARDS DUE TO BLOWING
SNOW SO IN THE NORTHERN HALF OF THE FORECAST AREA HAVE ISSUED A
WINTER WEATHER ADVISORY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 405 PM CDT MON MAR 17 2014
MODELS IN THE MID AND LONG TERM HAVE COME INTO BETTER AGREEMENT AT
H5 AND H7 AND WITH THE AMOUNT OF COLD AIR AT 850MB. TIMING IS GOOD
AND HAVE BETTER CONFIDENCE IN THE SOLUTIONS THAN YESTERDAY. TUESDAY
NIGHT WILL TAKE A LOOK LATE TO DECIDE TO INCLUDE WEATHER OVER NORTH
CENTRAL. SYSTEM BECOMES MORE STACKED OVER EASTERN NEBRASKA AND SLOWS
DOWN CONSIDERABLY. LOWS WEDNESDAY MORNING WITH -3C AT 850MB AND
CLEARING SKIES WITH SOME SNOW ON THE GROUND EXPECT TEMPERATURES IN
THE TEENS AND LOW 20S TO THE WEST NORTHWEST AND UPPER 20S NORTH
CENTRAL...ONEILL VICINITY. DOWN SLOPE FLOW AND THE RIDGE BUILDING
EAST WITH WARMER TEMPERATURES ALOFT SURFACE TEMPERATURES ACROSS THE
FORECAST AREA WILL BE SKEWED BY SNOW FIELD. COOLER 40S NORTH AND 50S
SOUTH. RIDGE CONTINUES INTO THURSDAY WITH SOUTHERLY FLOW WEDNESDAY
NIGHT AHEAD OF NEXT SYSTEM DROPPING INTO THE NORTHERN PLAINS
THURSDAY NIGHT. TEMPERATURES IN THE 50S AND 60S THURSDAY WITH MIXED
PRECIPITATION ALONG THE SOUTH DAKOTA NEBRASKA BORDER FRIDAY.
TEMPERATURES IN THE 30S AND 40S SATURDAY AND REBOUNDING THROUGH THE
FIRST OF THE WEEK WITH ONLY SLIGHT CHANCES OF PRECIPITATION AND NOT
WIDESPREAD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1203 AM CDT TUE MAR 18 2014
AS A STORM SYSTEM MAKES ITS WAY ACROSS NORTHERN NEBRASKA...A FRONT
WILL PLUNGE THROUGH TONIGHT AND EARLY TUESDAY. AS IT DOES...VERY
WINDY CONDITIONS WILL DEVELOP ALONG WITH LIGHT SNOW. IN THE CLOUDS
AND PRECIPITATION...VISIBILITY OF 1-3SM IS LIKELY ALONG WITH
CEILINGS AT OR BELOW 1000 FEET AGL. VISIBILITY IS EXPECTED TO BE
ABOVE VISUAL THRESHOLDS IN NORTHERN NEBRASKA BETWEEN 18Z AND 21Z...
BUT CEILING BELOW 1000 FEET AGL IS LIKELY UNTIL 22Z. IN SOUTHERN
NEBRASKA...VISIBILITY WILL BE AT OR ABOVE 3SM AROUND 21Z AND CEILING
ABOVE 1000 FEET AGL BY 00Z. THE 1000-2000 FT CEILING IS LIKELY TO
CONTINUE IN SOUTHWEST NEBRASKA UNTIL AFTER 03Z.
WIND 330-360 WILL INCREASE TO 20-25G30-36KT BY 13Z AND DECREASE TO
15-20G25-30 BY 02Z.
&&
.FIRE WEATHER...
ISSUED AT 1001 PM CDT MON MAR 17 2014
RELATIVE HUMIDITY HAS INCREASED TO 20 PERCENT OR HIGHER MOST AREAS
IN WESTERN AND NORTH CENTRAL NEBRASKA AND THE WIND HAS DECREASED
TO LESS THAN 20 MPH. THEREFORE...THE RED FLAG WARNING HAS EXPIRED.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 10 AM CDT /9 AM MDT/ THIS MORNING TO 9 PM CDT
/8 PM MDT/ THIS EVENING FOR NEZ038-056>059-069>071.
WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING
FOR NEZ004>010-022>029-035>037-094.
&&
$$
UPDATE...CDC
SYNOPSIS...POWER
SHORT TERM...BROOKS/JACOBS
LONG TERM...POWER
AVIATION...CDC
FIRE WEATHER...SPRINGER
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
254 AM EDT TUE MAR 18 2014
.SYNOPSIS...
MOSTLY CLEAR SKIES AND DRY WEATHER WILL PREVAIL TODAY, AS A
STRONG CANADIAN HIGH REMAINS OVER THE NORTHEAST UNITED STATES.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
1210 AM UPDATE...
SFC RIDGE AXIS EXTNDS FM HUDSON BAY SEWD OFF THE NEW ENGLAND
COAST, LEAVING CWA ON WRN PERIPHERY OF HIPRES. THIS HAS RESULTED
IN ESE WINDS AT THE SFC WITH WINDS JUST ABV THE SFC FM THE S-SW.
PER CCX VAD WIND PROFILE WINDS BLO 8KFT ARE FM THE SSW WITH KBGM
BEGINNING TO SHOW THE SAME WITHIN THE LAST HR. EXPECT THIS WL HELP
PUSH THE LOW CLDS NORTH INTO WRN AND SRN SXNS OF CWA WITHIN THE
NEXT 2-3 HRS PER LATEST RUC H8 RH VALUES. THUS, HV UPDATED GRIDS
TO GO PCLDY AND POSSIBLY MCLDY IN CERTAIN SPOTS OF SWRN CWA BY 06Z
WITH MOCLR ELSEWHERE. NO OTHER CHGS NEEDED TO GRIDS AT THIS TIME,
AS T/TD VALUES RIGHT ON TRACK.
PREV DISCOS BLO...
8 PM UPDATE... THE CURRENT FCST IS IN EXCELLENT SHAPE...SO JUST
SOME MINOR TEMP/DEW PT GRID TWEAKS ARE REQUIRED ATTM.
SAT IMAGERY SHOWS THAT THE NRN EDGE OF THE THICKER CLOUD SHIELD
ACRS PA HAS HELD STEADY THE LAST 3-6 HRS. NEAR-TERM GUIDANCE
CONTINUES TO INDICATE THAT AS A STG SFC RIDGE AXIS BUILDS SWD FROM
NEW ENG ALG THE EAST COAST OVERNIGHT...THIS CLOUD MASS WILL BE
HELD AT BAY OVER CNTRL/SRN PA. IN THE MEANTIME...PATCHY AND
RELATIVELY THIN MID AND UPR-LVL CLOUD DEBRIS ACRS THE UPR MIDWEST
MAY TRANSLATE EWD OVERNIGHT INTO TUE...PERHAPS RESULTING IN PDS OF
PTLY CLDY CONDS OVER OUR NRN ZNS. ELSEWHERE ACRS CNY/NE PA...SKIES
SHOULD REMAIN GENERALLY CLEAR.
LOW TEMPS SHOULD RANGE FROM THE SINGLE DIGITS OVER SOME OF OUR
NORMALLY COLDER SXNS IN THE CATSKILLS...SRN TUG HILL...AND NRN
FINGER LKS RGNS...TO MOSTLY TEENS ELSEWHERE.
120 PM EDT UPDATE...
MOSTLY CLEAR SKIES AND CALM WINDS WILL PREVAIL TODAY AND TONIGHT
AS CANADIAN HIGH PRESSURE BUILDS OVER THE REGION. TEMPERATURES
WILL SLOWLY INCREASE ACROSS THE CWA AND STRUGGLE TO REBOUND INTO
THE 20S/30S AS VERY COLD CANADIAN AIR HAS MOVED INTO CENTRAL NY
AND NORTHEAST PA DESPITE ABUNDANCE AMOUNTS OF SUNSHINE. EXPECT
HIGHS TODAY TO BE IN THE MID/UPPER 20S TO LOW 30S. DEW POINTS FOR
MUCH OF THE AREA ARE STILL BELOW ZERO AND DO NOT EXPECT MUCH
IMPROVEMENT TODAY... THUS TEMPS SHOULD BE QUITE CHILLY AGAIN
TONIGHT WITH LOWS IN THE LOW TEENS TO SINGLE DIGITS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
300 PM EDT UPDATE...
TUESDAY MORNING AN UPR LEVEL LOW WILL START TO MOVE EAST OF THE
ROCKIES INDUCING CYCLOGENESIS. THE SFC LOW WILL THEN PROPAGATE
EAST ACROSS THE CENTRAL PLAINS. BY WEDNESDAY MORNING THE SFC LOW
WILL THEN BE LOCATED OVER THE GREAT LAKES REGION. THE UP PR LOW
WILL THEN BECOME STACKED AND THE COLD FRONT WITH THE ATTENDANT
LOW WILL BECOME OCCLUDED.
THE SFC LOW WILL THEN SLOWLY MOVE OFF TO THE NORTH AND EAST OF THE
STATE OF NY. AS THIS LOW MOVES EAST IT WILL BRING A CHANCE FOR
RAIN/SNOW SHOWERS WED AFTERNOON/EVENING. AS THIS SYSTEM KEEPS
SLOWING DOWN... WITH EACH NEW MODEL RUN... TEMPS DURING THE
AFTERNOON/EVENING ON WED SHOULD BE ABLE TO INCREASE ENOUGH THAT
THE MAJORITY OF THE PRECIPITATION FALLING SHOULD BE RAIN. ALSO...
PRECIPITATION THAT FALLS WILL BE LIGHT AS WELL.
HIGHS TUES/WED WILL BE IN THE 40S AND LOWS WILL BE IN THE 20S
WED.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
230 AM UPDATE...
LITTLE CHANGE. COLD AND UNSETTLED. FOLLOWED WPC GUIDANCE WHICH
DID NOT DIFFER MUCH FROM YESTERDAY. MODELS DIFFER IN THE DETAILS
OF THE 2 STORMS FOR THIS PERIOD. EURO WEAKER AND CROSSES PA SAT
GIVING MIX SOUTH AND SNOW NORTH. THE GFS IS STRONGER BUT IN CANADA
SO RAIN TO SNOW. MUCH UNCERTAINTY ON SATURDAY. SAT NGT AND SUN
BOTH HAVE THE CAA AND LAKE ENHANCED SNOW WITH SECONDARY COLD FRONT
AND THE DIGGING UPPER LEVEL TROF. TUESDAY A SIMILAR SCENARIO WITH
THE GFS WARMER AND FURTHER NORTH.
PREVIOUS DISCUSSION...
MEDIUM RANGE MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED
PERIOD. OVERALL A CONTINUATION OF COLDER THAN NORMAL WEATHER AS AN
UPPER LEVEL TROF REMAINS OVER EASTERN CANADA/EASTERN UNITED
STATES.
EXTENDED BEGINS UNDER COLD NORTHWEST FLOW WITH LAKE EFFECT SNOW
SHOWERS EAST/SOUTHEAST OF LAKE ONTARIO. FRIDAY WILL BE DRY DUE TO
BRIEF SFC RIDGING.
FRIDAY NIGHT/SATURDAY, SFC LOW PRES WILL TRACK FROM THE MID WEST
ACROSS THE OHIO VALLEY TO NEW ENGLAND. THIS SYSTEM WILL BRING
SCATTERED RAIN/SNOW SHOWERS.
SATURDAY NIGHT THROUGH MONDAY, A COLD NORTHWEST FLOW OF CANADIAN
AIR WILL DOMINATE OUR WEATHER WITH FAIRLY DRY BUT COLD TEMPERATURES
AS READINGS RUN ABOUT 10 TO 20 DEGREES BELOW NORMAL. SATURDAY
NIGHT BEHIND DEPARTING COLD FRONT LAKE EFFECT SNOW SHOWERS ARE
POSSIBLE SOUTHEAST OF THE LAKE.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
130 AM UPDATE...
VFR CONDITIONS EXPECTED NEXT 24 HOURS. SCATTERED CLOUDS FIRST AT
HIGH LEVELS EARLY THIS MORNING THEN LOW END OF VFR THIS AFTN.
LIGHT AND VARIABLE WIND EARLY THIS MORNING. IF ANY DIRECTION EAST.
DURING THE DAY WINDS SHIFT TO SE AND INCREASE TO 5 TO 10 MPH.
OUTLOOK...
WED/THU...MVFR AND POSSIBLY IFR IN -SHRA/-SHSN.
THUR NGT...MVFR POSSIBLE IN LAKE EFFECT -SHSN, MAINLY ACROSS NY
TERMINALS.
FRIDAY/FRIDAY NIGHT...MAINLY VFR.
SATURDAY...RESTRICTIONS POSSIBLE IN RAIN/SNOW SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KAH/TAC
NEAR TERM...KAH/MLJ/PVN
SHORT TERM...KAH
LONG TERM...RRM/TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1212 AM EDT TUE MAR 18 2014
.SYNOPSIS...
MOSTLY CLEAR SKIES WILL PREVAIL TODAY AS A STRONG CANADIAN HIGH
BUILDS INTO THE REGION. THE HIGH PRESSURE SYSTEM WILL REMAIN
PARKED OVER THE REGION THROUGH TUESDAY BRINGING MAINLY CLEAR AND
DRY WEATHER.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
1210 AM UPDATE...
SFC RIDGE AXIS EXTNDS FM HUDSON BAY SEWD OFF THE NEW ENGLAND
COAST, LEAVING CWA ON WRN PERIPHERY OF HIPRES. THIS HAS RESULTED
IN ESE WINDS AT THE SFC WITH WINDS JUST ABV THE SFC FM THE S-SW.
PER CCX VAD WIND PROFILE WINDS BLO 8KFT ARE FM THE SSW WITH KBGM
BEGINNING TO SHOW THE SAME WITHIN THE LAST HR. EXPECT THIS WL HELP
PUSH THE LOW CLDS NORTH INTO WRN AND SRN SXNS OF CWA WITHIN THE
NEXT 2-3 HRS PER LATEST RUC H8 RH VALUES. THUS, HV UPDATED GRIDS
TO GO PCLDY AND POSSIBLY MCLDY IN CERTAIN SPOTS OF SWRN CWA BY 06Z
WITH MOCLR ELSEWHERE. NO OTHER CHGS NEEDED TO GRIDS AT THIS TIME,
AS T/TD VALUES RIGHT ON TRACK.
PREV DISCOS BLO...
8 PM UPDATE... THE CURRENT FCST IS IN EXCELLENT SHAPE...SO JUST
SOME MINOR TEMP/DEW PT GRID TWEAKS ARE REQUIRED ATTM.
SAT IMAGERY SHOWS THAT THE NRN EDGE OF THE THICKER CLOUD SHIELD
ACRS PA HAS HELD STEADY THE LAST 3-6 HRS. NEAR-TERM GUIDANCE
CONTINUES TO INDICATE THAT AS A STG SFC RIDGE AXIS BUILDS SWD FROM
NEW ENG ALG THE EAST COAST OVERNIGHT...THIS CLOUD MASS WILL BE
HELD AT BAY OVER CNTRL/SRN PA. IN THE MEANTIME...PATCHY AND
RELATIVELY THIN MID AND UPR-LVL CLOUD DEBRIS ACRS THE UPR MIDWEST
MAY TRANSLATE EWD OVERNIGHT INTO TUE...PERHAPS RESULTING IN PDS OF
PTLY CLDY CONDS OVER OUR NRN ZNS. ELSEWHERE ACRS CNY/NE PA...SKIES
SHOULD REMAIN GENERALLY CLEAR.
LOW TEMPS SHOULD RANGE FROM THE SINGLE DIGITS OVER SOME OF OUR
NORMALLY COLDER SXNS IN THE CATSKILLS...SRN TUG HILL...AND NRN
FINGER LKS RGNS...TO MOSTLY TEENS ELSEWHERE.
120 PM EDT UPDATE...
MOSTLY CLEAR SKIES AND CALM WINDS WILL PREVAIL TODAY AND TONIGHT
AS CANADIAN HIGH PRESSURE BUILDS OVER THE REGION. TEMPERATURES
WILL SLOWLY INCREASE ACROSS THE CWA AND STRUGGLE TO REBOUND INTO
THE 20S/30S AS VERY COLD CANADIAN AIR HAS MOVED INTO CENTRAL NY
AND NORTHEAST PA DESPITE ABUNDANCE AMOUNTS OF SUNSHINE. EXPECT
HIGHS TODAY TO BE IN THE MID/UPPER 20S TO LOW 30S. DEW POINTS FOR
MUCH OF THE AREA ARE STILL BELOW ZERO AND DO NOT EXPECT MUCH
IMPROVEMENT TODAY... THUS TEMPS SHOULD BE QUITE CHILLY AGAIN
TONIGHT WITH LOWS IN THE LOW TEENS TO SINGLE DIGITS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
300 PM EDT UPDATE...
TUESDAY MORNING AN UPR LEVEL LOW WILL START TO MOVE EAST OF THE
ROCKIES INDUCING CYCLOGENESIS. THE SFC LOW WILL THEN PROPAGATE
EAST ACROSS THE CENTRAL PLAINS. BY WEDNESDAY MORNING THE SFC LOW
WILL THEN BE LOCATED OVER THE GREAT LAKES REGION. THE UP PR LOW
WILL THEN BECOME STACKED AND THE COLD FRONT WITH THE ATTENDANT
LOW WILL BECOME OCCLUDED.
THE SFC LOW WILL THEN SLOWLY MOVE OFF TO THE NORTH AND EAST OF THE
STATE OF NY. AS THIS LOW MOVES EAST IT WILL BRING A CHANCE FOR
RAIN/SNOW SHOWERS WED AFTERNOON/EVENING. AS THIS SYSTEM KEEPS SLOWING
DOWN... WITH EACH NEW MODEL RUN... TEMPS DURING THE AFTERNOON/EVENING
ON WED SHOULD BE ABLE TO INCREASE ENOUGH THAT THE MAJORITY OF THE
PRECIPITATION FALLING SHOULD BE RAIN. ALSO... PRECIPITATION THAT FALLS
WILL BE LIGHT AS WELL.
HIGHS TUES/WED WILL BE IN THE 40S AND LOWS WILL BE IN THE 20S
WED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
MEDIUM RANGE MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED
PERIOD. OVERALL A CONTINUATION OF COLDER THAN NORMAL WEATHER AS AN
UPPER LEVEL TROF REMAINS OVER EASTERN CANADA/EASTERN UNITED
STATES.
EXTENDED BEGINS UNDER COLD NORTHWEST FLOW WITH LAKE EFFECT SNOW
SHOWERS EAST/SOUTHEAST OF LAKE ONTARIO. FRIDAY WILL BE DRY DUE TO
BRIEF SFC RIDGING.
FRIDAY NIGHT/SATURDAY, SFC LOW PRES WILL TRACK FROM THE MID WEST
ACROSS THE OHIO VALLEY TO NEW ENGLAND. THIS SYSTEM WILL BRING
SCATTERED RAIN/SNOW SHOWERS.
SATURDAY NIGHT THROUGH MONDAY, A COLD NORTHWEST FLOW OF CANADIAN
AIR WILL DOMINATE OUR WEATHER WITH FAIRLY DRY BUT COLD TEMPERATURES
AS READINGS RUN ABOUT 10 TO 20 DEGREES BELOW NORMAL. SATURDAY
NIGHT BEHIND DEPARTING COLD FRONT LAKE EFFECT SNOW SHOWERS ARE
POSSIBLE SOUTHEAST OF THE LAKE.
&&
.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
VFR CONDITIONS EXPECTED THROUGH THE FCST CYCLE AS HIGH PRESSURE
REMAINS IN CONTROL. ASIDE FROM SOME HIGH CIRRUS OVERNIGHT...EXPECT
MAINLY CLEAR SKIES ACROSS MOST CNY TERMINALS. FURTHER SOUTH AT
AVP...SOME MID-LEVEL CLOUDS CENTERED AROUND 9 KFT WILL LINGER INTO
THE EVENING BEFORE DISSIPATION OCCURS OVERNIGHT. WINDS WILL REMAIN
FROM THE SOUTHEAST THROUGH THE PERIOD...WITH SPEEDS GENERALLY LESS
THAN 5 KTS.
OUTLOOK...
WED/THU...MVFR POSSIBLE IN -SHRA/-SHSN.
THUR NGT...MVFR POSSIBLE IN LAKE EFFECT -SHRA/-SHSN, MAINLY
ACROSS NY TERMINALS.
FRIDAY/FRIDAY NIGHT...MAINLY VFR.
SATURDAY...RESTRICTIONS POSSIBLE IN RAIN/SNOW SHOWERS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KAH
NEAR TERM...KAH/MLJ/PVN
SHORT TERM...KAH
LONG TERM...RRM
AVIATION...CMG
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 AM EDT TUE MAR 18 2014
.SYNOPSIS...A LATE SEASON COLD AIR DAMMING WEDGE WILL REMAIN IN
PLACE THROUGH WEDNESDAY AS MODIFIED ARCTIC HIGH PRESSURE EXTENDS
SOUTHWARD INTO THE REGION AND MULTIPLE WAVES OF LOW PRESSURE DEVELOP
ALONG AND OFFSHORE THE CAROLINA COAST.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 1030 PM MONDAY...
TONIGHT: HIGH-END ADVISORY (BUT SUB-WARNING CRITERIA) ICING WITH
DISCOURAGED TRAVEL CONDITIONS OVER THE NORTHERN PIEDMONT...TO MORE
NUISANCE-TYPE IMPACTS WITH A FEW SLICK BRIDGES AND OVERPASSES ALONG
SOUTHERN ADVISORY AREAS OF THE SOUTHERN PIEDMONT...SANDHILLS...AND
CENTRAL COASTAL PLAIN.
A DEAMPLIFYING...POSITIVELY-TILTED SHORTWAVE TROUGH/SHEARING
VORTICITY MAX CENTERED OVER THE SOUTHERN APPALACHIANS THIS EVENING
WILL CONTINUE TO SHEAR NORTHEASTWARD INTO EASTERN NC...WHILE A MORE
POTENT ONE OVER THE MS DELTA REGION ASSUMES A NEGATIVE TILT AND
PIVOTS (HARMLESSLY FOR CENTRAL NC) ACROSS THE NORTHERN FL PENINSULA
TO OFFSHORE THE GA/SC COAST...THROUGH EARLY TUESDAY. DCVA ATTENDANT
TO THE LEAD DEAMPLIFYING WAVE SEEMS TO BE THE PRIMARY FORCING
MECHANISM FOR THE PRECIPITATION AREA THAT EXPANDED FROM WESTERN SC
TO THE NW NC PIEDMONT DURING THE PAST FEW HOURS. THIS FORCING...AND
ASSOCIATED MIXED PHASE PRECIPITATION PRODUCTION SUPPORTIVE OF 1) A
MIX OF SLEET WITH THE FREEZING RAIN AND 2) MODERATE PRECIPITATION
INTENSITY...SHOULD CONSEQUENTLY EDGE EASTWARD ACROSS CENTRAL NC -
THROUGH 05-06Z IN THE SOUTHERN AND WESTERN PIEDMONT AND 07-09Z IN
THE NORTHEAST PIEDMONT AND NORTHERN COASTAL PLAIN.
HOURLY PRECIPITATION RATES HAVE RANGED FROM A COUPLE OF HUNDREDTHS
TO MORE RECENTLY AS MUCH AS SIX HUNDREDTHS OF AN INCH IN THE
EXPANDING AREA OF PRECIPITATION. THESE HOURLY PRECIPITATION RATES
DURING THE TIMING REFERENCED ABOVE...WHICH IS CORROBORATED WITH NEAR
TERM RAP AND HRRR NWP GUIDANCE...WILL SUPPORT LIQUID EQUIVALENT
AMOUNTS OF 0.15"...TO PERHAPS AS MUCH AS ONE THIRD OF AN INCH IN
ISOLATED SPOTS. CONSIDERED UPGRADING PORTIONS OF THE ADVISORY
AREA...SUCH AS GUILFORD AND ALAMANCE NORTHEASTWARD TO COUNTIES ALONG
THE VA BORDER...TO A WARNING. HOWEVER...THE TENDENCY OF THE
PRECIPITATION TO SWITCH BETWEEN OR CONSIST OF A MIX OF SLEET AND
FREEZING RAIN - OWING TO A 00Z GSO-OBSERVED 4 C WARM NOSE AND MINUS
7 C COLD NOSE BELOW - SHOULD LIMIT ACCUMULATIONS OF ANY ONE
PRECIPITATION TYPE. HAVE INSTEAD OPTED TO "HIT THE WORDING A LITTLE
HARDER" IN THE ADVISORY...WITH SLEET ACCUMULATION AROUND A QUARTER
INCH OR LESS...AND FREEZING RAIN OF ONE TO TWO TENTHS OF AN
INCH...DERIVED FROM A 50/50 MIX OF FREEZING RAIN AND SLEET WITH
RATIOS OF 3-4:1...FROM THE AFOREMENTIONED LIQUID EQUIVALENT AMOUNTS
OF 0.15-0.30" OR SO. RECENT CHECKS WITH DUKE ENERGY INDICATE POWER
OUTAGES HAVE BEEN RELATIVELY SPARSE THUS FAR...WHICH SUGGESTS ICE
ACCRUAL IS NOT APPROACHING WARNING CRITERIA AND WELL-HANDLED BY THE
ADVISORY...DESPITE NUMEROUS CAR ACCIDENTS - INCLUDING AT LEAST
ONE FIERY ONE IN THE TRIAD.
ONCE THE MIXED PHASE PRECIPITATION COMES TO AN END...PERIODS OF
MOSTLY NON-MEASURABLE "DRIZZLY" PRECIPITATION - FREEZING IN THE
ADVISORY AREA AND LIQUID ELSEWHERE - WILL PREVAIL. 10 PM
TEMPERATURES WILL HOLD NEARLY STEADY IN THE UPPER 20S OVER THE
NORTHERN PIEDMONT...TO LOWER TO MIDDLE 30S OVER THE SOUTHERN
PIEDMONT AND SANDHILLS. -MWS
TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING BY LATE
MORNING/AROUND LUNCHTIME ACROSS THE NORTHERN PIEDMONT(EARLIER ACROSS
THE SOUTHERN PORTIONS OF THE ADVISORY AREA) AS THE MEASURABLE PRECIP
BEGINS TO PULL OUT OF THE AREA WITH THE EXITING UPPER WAVE.
SOUNDINGS SUPPORT CONTINUED LOW CLOUDS WITH POSSIBLE PATCHY/ISOLATED
DRIZZLE THROUGH THE AFTERNOON. HIGHS IN THE UPPER 30S NORTH TO
MID/UPPER 40S SOUTH. -CBL
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM TUESDAY...
COLD RIDGING REMAINS IN PLACE TONIGHT WITH A LOW AMPLITUDE SHORT
WAVE RIDGE AND DRYING ALOFT. FLOW ATOP THE COLD DOME VEERS SOUTHERLY
AND STRENGTHENS OVERNIGHT...WHILE THE SATURATED PORTION OF THE
MOISTURE PROFILE CUTS OFF AROUND 6KFT. ISENTROPIC LIFT WILL BE WEAK
FROM THE SOUTHEAST EARLY OVERNIGHT AS THE FLOW SWINGS AROUND...HENCE
PRECIP WILL BE PATCHY AND LIGHT WITH AN ASSOCIATED TEMP PROFILE IN
THE LIQUID RANGE. NEAR NEUTRAL ADVECTION AND LOSS OF REINFORCING
EVAPORATIVE COOLING WILL MAINTAIN TEMPS NEARLY STEADY FROM 35 TO 40.
EROSION OF THE CAD WILL BE UNDERWAY EARLY WEDNESDAY...WITH DEEP
SOUTHWEST WARM AIR ADVECTION AHEAD OF AN APPROACHING `COLD` FRONT.
DYNAMICS WILL BE WEAK WITH THE PARENT SYSTEM WELL NORTH OF THE AREA
AND MOISTURE WILL BE LIMITED AHEAD OF THE FRONT WITH WESTERLY FLOW
ACROSS THE NORTHERN GULF...HENCE ONLY A SLIGHT CHANCE OF SHOWERS.
TEMPERATURES WILL RISE DRAMATICALLY AS EROSION OF THE COLD AIR FROM
THE SOUTH AND WEST WILL PROMOTE A FAST WARMUP ALONG THE FRINGES...
AND THERE COULD BE SOME BREAKS IN THE CLOUDINESS AS WELL. TIMING THE
WARMUP IS A PROBLEMATIC...AND THE NORTHEAST COULD SEE WARMUP DELATED
TIL LATER AFTERNOON. REGARDLESS...HIGHS IN THE 50S WILL BE WELCOMED
AFTER THE PAST COUPLE OF DAYS.
ANOTHER COOL NIGHT IS ON TAP WITH POST FROPA COLD AIR ADVECTION
WEDNSDAY NIGHT. MINS WILL FALL TO 40 TO 45...WITH SKIES BECOMING
MOSTLY CLEAR.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 230 AM TUESDAY...
THURSDAY AND THURSDAY NIGHT...BROAD UPPER TROF PASSES BY
ALOFT...WITH HEIGHTS BEGINNING TO BUILD AND MILD HIGH PRESSURE EDGES
IN FROM THE SOUTHWEST. LOOKING AT MOSTLY SUNNY SKIES WITH HIGHS
REACHING THE MID 60S THURSDAY. GOOD RADIATION CONDITIONS PROMOTE A F
FRIDAY AND SATURDAY: FRIDAY LOOKS VERY PLEASANT AT THIS TIME AS
CENTRAL NORTH CAROLINA WILL BE IN A SOUTHWEST FLOW REGIME ON THE
BACK SIDE OF A SURFACE HIGH PRESSURE THAT WILL BE MOVING OUT INTO
THE WESTERN ATLANTIC. FLOW ALOFT WILL BE VERY ZONAL. MOSTLY CLEAR
SKIES WILL DOMINATE WITH TEMPERATURES IN THE UPPER 60S TO LOW 70S
AND LOWS NEAR 50 DEGREES FRIDAY NIGHT WITH INCREASING CLOUDINESS BY
DAYBREAK ON SATURDAY.
PARTLY TO MOSTLY CLOUDY SKIES WILL PREVAIL ON SATURDAY AS A SURFACE
LOW PRESSURE SYSTEM MOVES THROUGH THE GREAT LAKES WITH ATTENDANT
FRONT APPROACHING FROM THE WEST. WARM SOUTHWESTERLY FLOW WILL
CONTINUE OUT AHEAD OF THE FRONT WHICH DESPITE THE CLOUDS...WILL
ALLOW TEMPERATURES TO CLIMB ONCE AGAIN INTO THE UPPER 60S TO LOWER
70S NW TO SE. FRONT IS PROGGED TO CROSS THROUGH CENTRAL NC NEAR 00Z
SUNDAY. DESPITE THE FAVORABLE DIURNAL TIMING...MODEL SOLUTIONS
DIFFER AS TO THE AMOUNT OF QPF...IF ANY DURING FRONTAL PASSAGE. THE
GFS IS THE WETTER SOLUTION WITH THE ECMWF COMING THROUGH AS MOSTLY
DRY. FORECAST SOUNDINGS SHOW SOME VERY WEAK INSTABILITY SATURDAY
EVENING WITH SB CAPE VALUES LESS THAN 300 J/KG WITH BULK SHEAR
VALUES OF 30-40 KTS. WILL KEEP CONVECTIVE SHOWERS IN AS THE
PREDOMINANT WEATHER TYPE AT THIS TIME EVEN THOUGH AN OUTSIDE
POSSIBILITY OF THUNDER REMAINS. NORTHWESTERLY FLOW WILL ENSUE AFTER
FRONTAL PASSAGE AND COLD AIR ADVECTION WILL BEGIN...KNOCKING LOW
TEMPERATURES DOWN ABOUT 10 DEGREES LOWER THAN FRIDAY NIGHT...MID 30S
TO LOWER 40S.
SUNDAY THROUGH MONDAY NIGHT: COOLER DAY FOR SUNDAY AS NORTHEASTERLY
FLOW TAKES OVER AT THE SURFACE AND HIGHS SCALE BACK TO THE MID 50S
TO NEAR 60 DEGREES...DESPITE MOSTLY CLEAR SKIES. WILL STILL BE ON
THE FRONT SIDE OF THE UPPER LEVEL TROUGH HOWEVER AS THIS WILL NOT
CROSS THE AREA UNTIL SUNDAY NIGHT AND WITH IT A REINFORCING DRY COLD
FRONT AT THE SURFACE. ONCE THIS MOVES THROUGH NORTHERLY FLOW AT THE
SURFACE AND NW FLOW ALOFT WILL BRING LOW TEMPERATURES DOWN INTO THE
LOW TO MID 30S.
ON MONDAY...A 1025 MB HIGH PRESSURE WILL MOVE ACROSS THE
NORTHEASTERN STATES...KEEPING CONDITIONS DRY BUT COOL ACROSS CENTRAL
NC. AS THE HIGH MOVES INTO A FAVORABLE LOCATION FOR HYBRID
DAMMING...CLOUD COVER WILL INCREASE ACROSS THE STATE FROM THE WEST.
WHILE A WEDGE FRONT WILL DEVELOP...THE STRENGTH OF THE HIGH IS
WEAKER THAN OPTIMAL FOR HYBRID CAD WHICH MAY TAME THE EFFECTS OF IT
A LITTLE BIT. REGARDLESS...COOLER HIGHS IN THE LOW TO MID 50S WITH
LOWS MONDAY NIGHT IN THE MID TO UPPER 30S. THERE IS QUESTION IN THE
MODELS ON WHETHER OR NOT PRECIPITATION WILL BE APPROACHING THE AREA
BETWEEN A STRONG LOW OVER THE UPPER MIDWEST AND A DEVELOPING LOW IN
THE SW ATLANTIC. ECMWF IS DRY AT THIS TIME WITH THE GFS SUPPORTING A
WETTER SOLUTION. CONFIDENCE IN EITHER RUN IS VERY LOW AT THIS TIME
AND THEREFORE WILL KEEP THE FORECAST DRY FOR NOW.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 847 PM MONDAY...
IFR CONDITIONS CURRENTLY ACROSS THE AREA WILL CONTINUE THROUGH THE
NEXT 24 HOURS UNDER A COLD AIR DAMMING REGIME. LIGHT FREEZING
RAIN... FREEZING DRIZZLE AND SLEET WILL CONTINUE OVERNIGHT... BEFORE
CHANGING TO DRIZZLE BETWEEN 12-15Z TUESDAY AT MOST SITES... WITH THE
EXCEPTION OF KFAY WHICH SHOULD REMAIN DRIZZLE/LIGHT RAIN THROUGH THE
DURATION. WINDS WILL REMAIN NE AROUND 8-10 KTS.
BEYOND THE 18Z VALID TAF PERIOD...ADVERSE AVIATION CONDITIONS...
PARTICULARLY IN IFR AND OCCASIONAL MVFR CEILINGS...AND AREAS OF
DRIZZLE AND SPOTTY LIGHT RAIN...SHOULD PERSIST INTO WEDNESDAY.
FINALLY ON WEDNESDAY...CEILINGS SHOULD GRADUALLY START TO LIFT...
ALTHOUGH IT SHOULD BE NOTED THAT ON SOME GUIDANCE THE CEILINGS OVER
THE NORTHWEST PIEDMONT MAY NOT IMPROVE MARKEDLY UNTIL INTO WEDNESDAY
NIGHT. IF WINDS LIGHTEN UP AS SKIES CLEAR...AT LEAST SOME LIGHT FOG
COULD DEVELOP WEDNESDAY NIGHT.
THURSDAY THROUGH FRIDAY...ANTICIPATE VFR CONDITIONS. LATE FRIDAY
NIGHT INTO SATURDAY...THERE IS THE POTENTIAL FOR AREAS OF SUB-VFR
CONDITIONS IN LOW CLOUDS AND SHOWERS...ALONG AND AHEAD OF A COLD
FRONT THAT WILL MOVE THROUGH THE REGION ON SATURDAY. COLDER HIGH
PRESSURE AND DRIER AIR THEN BUILD IN FROM THE NORTH SATURDAY NIGHT
INCREASING PROBABILITIES OF A RETURN TO WIDESPREAD VFR CONDITIONS.
&&
.CLIMATE...
THE RECORD LOW MAXIMUM TEMPERATURES FOR MARCH 18 (TUESDAY) ARE...
KGSO...36 DEGREES FROM 1961.
KRDU...36 DEGREES FROM 1892.
KFAY...41 DEGREES FROM 1998.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO NOON EDT
TUESDAY FOR NCZ011-026>028-040>043-073>077.
WINTER WEATHER ADVISORY UNTIL NOON EDT TUESDAY FOR NCZ007>010-
021>025-038-039.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...MWS/CBL
SHORT TERM...MLM
LONG TERM...ELLIS
AVIATION...SEC/DJF
CLIMATE...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
236 AM EDT TUE MAR 18 2014
.SYNOPSIS...A LATE SEASON COLD AIR DAMMING WEDGE WILL REMAIN IN
PLACE THROUGH WEDNESDAY AS MODIFIED ARCTIC HIGH PRESSURE EXTENDS
SOUTHWARD INTO THE REGION AND MULTIPLE WAVES OF LOW PRESSURE DEVELOP
ALONG AND OFFSHORE THE CAROLINA COAST.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 1030 PM MONDAY...
TONIGHT: HIGH-END ADVISORY (BUT SUB-WARNING CRITERIA) ICING WITH
DISCOURAGED TRAVEL CONDITIONS OVER THE NORTHERN PIEDMONT...TO MORE
NUISANCE-TYPE IMPACTS WITH A FEW SLICK BRIDGES AND OVERPASSES ALONG
SOUTHERN ADVISORY AREAS OF THE SOUTHERN PIEDMONT...SANDHILLS...AND
CENTRAL COASTAL PLAIN.
A DEAMPLIFYING...POSITIVELY-TILTED SHORTWAVE TROUGH/SHEARING
VORTICITY MAX CENTERED OVER THE SOUTHERN APPALACHIANS THIS EVENING
WILL CONTINUE TO SHEAR NORTHEASTWARD INTO EASTERN NC...WHILE A MORE
POTENT ONE OVER THE MS DELTA REGION ASSUMES A NEGATIVE TILT AND
PIVOTS (HARMLESSLY FOR CENTRAL NC) ACROSS THE NORTHERN FL PENINSULA
TO OFFSHORE THE GA/SC COAST...THROUGH EARLY TUESDAY. DCVA ATTENDANT
TO THE LEAD DEAMPLIFYING WAVE SEEMS TO BE THE PRIMARY FORCING
MECHANISM FOR THE PRECIPITATION AREA THAT EXPANDED FROM WESTERN SC
TO THE NW NC PIEDMONT DURING THE PAST FEW HOURS. THIS FORCING...AND
ASSOCIATED MIXED PHASE PRECIPITATION PRODUCTION SUPPORTIVE OF 1) A
MIX OF SLEET WITH THE FREEZING RAIN AND 2) MODERATE PRECIPITATION
INTENSITY...SHOULD CONSEQUENTLY EDGE EASTWARD ACROSS CENTRAL NC -
THROUGH 05-06Z IN THE SOUTHERN AND WESTERN PIEDMONT AND 07-09Z IN
THE NORTHEAST PIEDMONT AND NORTHERN COASTAL PLAIN.
HOURLY PRECIPITATION RATES HAVE RANGED FROM A COUPLE OF HUNDREDTHS
TO MORE RECENTLY AS MUCH AS SIX HUNDREDTHS OF AN INCH IN THE
EXPANDING AREA OF PRECIPITATION. THESE HOURLY PRECIPITATION RATES
DURING THE TIMING REFERENCED ABOVE...WHICH IS CORROBORATED WITH NEAR
TERM RAP AND HRRR NWP GUIDANCE...WILL SUPPORT LIQUID EQUIVALENT
AMOUNTS OF 0.15"...TO PERHAPS AS MUCH AS ONE THIRD OF AN INCH IN
ISOLATED SPOTS. CONSIDERED UPGRADING PORTIONS OF THE ADVISORY
AREA...SUCH AS GUILFORD AND ALAMANCE NORTHEASTWARD TO COUNTIES ALONG
THE VA BORDER...TO A WARNING. HOWEVER...THE TENDENCY OF THE
PRECIPITATION TO SWITCH BETWEEN OR CONSIST OF A MIX OF SLEET AND
FREEZING RAIN - OWING TO A 00Z GSO-OBSERVED 4 C WARM NOSE AND MINUS
7 C COLD NOSE BELOW - SHOULD LIMIT ACCUMULATIONS OF ANY ONE
PRECIPITATION TYPE. HAVE INSTEAD OPTED TO "HIT THE WORDING A LITTLE
HARDER" IN THE ADVISORY...WITH SLEET ACCUMULATION AROUND A QUARTER
INCH OR LESS...AND FREEZING RAIN OF ONE TO TWO TENTHS OF AN
INCH...DERIVED FROM A 50/50 MIX OF FREEZING RAIN AND SLEET WITH
RATIOS OF 3-4:1...FROM THE AFOREMENTIONED LIQUID EQUIVALENT AMOUNTS
OF 0.15-0.30" OR SO. RECENT CHECKS WITH DUKE ENERGY INDICATE POWER
OUTAGES HAVE BEEN RELATIVELY SPARSE THUS FAR...WHICH SUGGESTS ICE
ACCRUAL IS NOT APPROACHING WARNING CRITERIA AND WELL-HANDLED BY THE
ADVISORY...DESPITE NUMEROUS CAR ACCIDENTS - INCLUDING AT LEAST
ONE FIERY ONE IN THE TRIAD.
ONCE THE MIXED PHASE PRECIPITATION COMES TO AN END...PERIODS OF
MOSTLY NON-MEASURABLE "DRIZZLY" PRECIPITATION - FREEZING IN THE
ADVISORY AREA AND LIQUID ELSEWHERE - WILL PREVAIL. 10 PM
TEMPERATURES WILL HOLD NEARLY STEADY IN THE UPPER 20S OVER THE
NORTHERN PIEDMONT...TO LOWER TO MIDDLE 30S OVER THE SOUTHERN
PIEDMONT AND SANDHILLS. -MWS
TEMPERATURES ARE EXPECTED TO CLIMB ABOVE FREEZING BY LATE
MORNING/AROUND LUNCHTIME ACROSS THE NORTHERN PIEDMONT(EARLIER ACROSS
THE SOUTHERN PORTIONS OF THE ADVISORY AREA) AS THE MEASURABLE PRECIP
BEGINS TO PULL OUT OF THE AREA WITH THE EXITING UPPER WAVE.
SOUNDINGS SUPPORT CONTINUED LOW CLOUDS WITH POSSIBLE PATCHY/ISOLATED
DRIZZLE THROUGH THE AFTERNOON. HIGHS IN THE UPPER 30S NORTH TO
MID/UPPER 40S SOUTH. -CBL
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...
AN UPPER RIDGE MOVES THROUGH TUESDAY NIGHT...WITH INCREASING
DIFFLUENCE WEDNESDAY BEHIND THE RIDGE...AND IN ADVANCE OF AN UPPER
TROUGH THAT SHOULD MOVE INTO THE AREA BY THURSDAY. GUIDANCE OVER THE
LAST DAY OR SO HAS BEEN CONSISTENT IN THIS SYNOPTIC TREND...WITH ONE
DIFFERENCE BEING CONSISTENCY IN THE GUIDANCE MOVING THE SURFACE
FRONT THROUGH FASTER...POSSIBLY AS EARLY AS OVERNIGHT WEDNESDAY INTO
EARLY THURSDAY. THE COLD AIR WEDGE SHOULD REMAIN INTO MUCH OF THE
DAY WEDNESDAY...POSSIBLY STARTING TO ERODE LATE WEDNESDAY INTO
WEDNESDAY EVENING IN ADVANCE OF THE FRONT.
ANOTHER LONG-TERM CONSISTENCY IS KEEPING WET BULB SURFACE
TEMPERATURES ABOVE 0C IN CENTRAL NORTH CAROLINA FOR TUESDAY NIGHT
INTO WEDNESDAY. PARTIAL THICKNESSES ARE ALSO PRIMARILY IN THE LIQUID
RANGE AND ARE ACTUALLY WARMER ON THE NAM OVERNIGHT TUESDAY INTO
EARLY WEDNESDAY...WITH ONLY THE PERIOD AROUND 06Z WEDNESDAY ON THE
GFS POSSIBLY INTO THE FREEZING RANGE. HOWEVER...WITH SURFACE
TEMPERATURES FORECAST TO STAY JUST ABOVE FREEZING AT THEIR
COLDEST...WILL CONTINUE THE FORECAST OF ANY PRECIPITATION TYPE BEING
LIQUID IN THIS PART OF THE FORECAST PERIOD.
FOR TUESDAY NIGHT INTO WEDNESDAY MORNING...BOTH THE GFS AND NAM BUFR
SOUNDINGS MAINTAIN A VERY MOIST BOUNDARY LAYER. SHALLOW INSTABILITY
NEAR THE TOP OF THE MOIST LAYER INCREASES OVERNIGHT TUESDAY INTO
WEDNESDAY MORNING AS THAT MOIST LAYER DEEPENS. EARLY AT NIGHT...ANY
PRECIPITATION WOULD LIKELY BE DRIZZLE OR VERY PATCHY LIGHT RAIN...
WITH A CHANCE OF RAIN AND DRIZZLE OVERNIGHT THROUGH WEDNESDAY
MORNING FOR MUCH OF CENTRAL NORTH CAROLINA AS...ADDITIONALLY...A MID-
LEVEL SHORTWAVE MOVES IN AND THERE EXISTS WEAK 850MB LIFT. DURING
THE DAY WEDNESDAY...BOUNDARY LAYER MOISTURE BECOMES MORE SHALLOW.
THE GFS...AND EVEN THE NAM BUT TO A LESSER DEGREE...INCREASES WINDS
AT 850MB APPRECIABLY AND IT WILL BE INTERESTING TO SEE WHETHER THESE
WINDS AND SOME WARM-AIR ADVECTION EITHER AT OR JUST BELOW 850MB
HELPS TO CAP SOME OF THE MOISTURE FURTHER OR HELPS ERODE THE CLOUD
COVER. THE NAM IS ACTUALLY MORE AGGRESSIVE WITH SOME CLEARING AND
WARMING LATE...BUT FOR THIS FORECAST WILL LEAN SLOWER WITH THE WEDGE
NOT COMPLETELY ERODING UNTIL WEDNESDAY NIGHT CLOSER TO THE APPROACH
OF THE SURFACE FRONT.
WEDNESDAY NIGHT...THE GFS IS DRY AND MORE STABLE THAN THE NAM...
ALTHOUGH THE GFS DOES FORECAST A WEAK INCREASE IN 850MB THETA-E
VALUES AND THE APPROACH OF THE RIGHT ENTRANCE REGION OF A 115KT
300MB JET...AND A 90KT 500MB JET. WILL SHOW JUST A SLIGHT CHANCE OF
SHOWERS THROUGHOUT THE NIGHT FOR NOW. BUFR SOUNDINGS FROM BOTH THE
GFS AND NAM WOULD SUGGEST THAT...WITH THE APPROACH OF THE JETS
ALOFT...ALONG WITH THE APPROACHING FRONT...AT LEAST A SLIGHT CHANCE
IS WARRANTED AS MID-LEVEL MOISTURE INCREASES FOR A PERIOD. AS FOR
TEMPERATURES IN THIS PERIOD...AFTER LOWS MOSTLY IN THE 30S TUESDAY
NIGHT...WILL LEAN TOWARD THE COOLER MAV MOS FOR HIGHS WEDNESDAY...
AND SHOW ONLY A MODEST DIURNAL FALL WEDNESDAY NIGHT IN A SOUTHWEST
TO WEST LOW-LEVEL FLOW IN ADVANCE OF THE FRONT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 230 AM TUESDAY...
FRIDAY AND SATURDAY: FRIDAY LOOKS VERY PLEASANT AT THIS TIME AS
CENTRAL NORTH CAROLINA WILL BE IN A SOUTHWEST FLOW REGIME ON THE
BACK SIDE OF A SURFACE HIGH PRESSURE THAT WILL BE MOVING OUT INTO
THE WESTERN ATLANTIC. FLOW ALOFT WILL BE VERY ZONAL. MOSTLY CLEAR
SKIES WILL DOMINATE WITH TEMPERATURES IN THE UPPER 60S TO LOW 70S
AND LOWS NEAR 50 DEGREES FRIDAY NIGHT WITH INCREASING CLOUDINESS BY
DAYBREAK ON SATURDAY.
PARTLY TO MOSTLY CLOUDY SKIES WILL PREVAIL ON SATURDAY AS A SURFACE
LOW PRESSURE SYSTEM MOVES THROUGH THE GREAT LAKES WITH ATTENDANT
FRONT APPROACHING FROM THE WEST. WARM SOUTHWESTERLY FLOW WILL
CONTINUE OUT AHEAD OF THE FRONT WHICH DESPITE THE CLOUDS...WILL
ALLOW TEMPERATURES TO CLIMB ONCE AGAIN INTO THE UPPER 60S TO LOWER
70S NW TO SE. FRONT IS PROGGED TO CROSS THROUGH CENTRAL NC NEAR 00Z
SUNDAY. DESPITE THE FAVORABLE DIURNAL TIMING...MODEL SOLUTIONS
DIFFER AS TO THE AMOUNT OF QPF...IF ANY DURING FRONTAL PASSAGE. THE
GFS IS THE WETTER SOLUTION WITH THE ECMWF COMING THROUGH AS MOSTLY
DRY. FORECAST SOUNDINGS SHOW SOME VERY WEAK INSTABILITY SATURDAY
EVENING WITH SB CAPE VALUES LESS THAN 300 J/KG WITH BULK SHEAR
VALUES OF 30-40 KTS. WILL KEEP CONVECTIVE SHOWERS IN AS THE
PREDOMINANT WEATHER TYPE AT THIS TIME EVEN THOUGH AN OUTSIDE
POSSIBILITY OF THUNDER REMAINS. NORTHWESTERLY FLOW WILL ENSUE AFTER
FRONTAL PASSAGE AND COLD AIR ADVECTION WILL BEGIN...KNOCKING LOW
TEMPERATURES DOWN ABOUT 10 DEGREES LOWER THAN FRIDAY NIGHT...MID 30S
TO LOWER 40S.
SUNDAY THROUGH MONDAY NIGHT: COOLER DAY FOR SUNDAY AS NORTHEASTERLY
FLOW TAKES OVER AT THE SURFACE AND HIGHS SCALE BACK TO THE MID 50S
TO NEAR 60 DEGREES...DESPITE MOSTLY CLEAR SKIES. WILL STILL BE ON
THE FRONT SIDE OF THE UPPER LEVEL TROUGH HOWEVER AS THIS WILL NOT
CROSS THE AREA UNTIL SUNDAY NIGHT AND WITH IT A REINFORCING DRY COLD
FRONT AT THE SURFACE. ONCE THIS MOVES THROUGH NORTHERLY FLOW AT THE
SURFACE AND NW FLOW ALOFT WILL BRING LOW TEMPERATURES DOWN INTO THE
LOW TO MID 30S.
ON MONDAY...A 1025 MB HIGH PRESSURE WILL MOVE ACROSS THE
NORTHEASTERN STATES...KEEPING CONDITIONS DRY BUT COOL ACROSS CENTRAL
NC. AS THE HIGH MOVES INTO A FAVORABLE LOCATION FOR HYBRID
DAMMING...CLOUD COVER WILL INCREASE ACROSS THE STATE FROM THE WEST.
WHILE A WEDGE FRONT WILL DEVELOP...THE STRENGTH OF THE HIGH IS
WEAKER THAN OPTIMAL FOR HYBRID CAD WHICH MAY TAME THE EFFECTS OF IT
A LITTLE BIT. REGARDLESS...COOLER HIGHS IN THE LOW TO MID 50S WITH
LOWS MONDAY NIGHT IN THE MID TO UPPER 30S. THERE IS QUESTION IN THE
MODELS ON WHETHER OR NOT PRECIPITATION WILL BE APPROACHING THE AREA
BETWEEN A STRONG LOW OVER THE UPPER MIDWEST AND A DEVELOPING LOW IN
THE SW ATLANTIC. ECMWF IS DRY AT THIS TIME WITH THE GFS SUPPORTING A
WETTER SOLUTION. CONFIDENCE IN EITHER RUN IS VERY LOW AT THIS TIME
AND THEREFORE WILL KEEP THE FORECAST DRY FOR NOW.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 847 PM MONDAY...
IFR CONDITIONS CURRENTLY ACROSS THE AREA WILL CONTINUE THROUGH THE
NEXT 24 HOURS UNDER A COLD AIR DAMMING REGIME. LIGHT FREEZING
RAIN... FREEZING DRIZZLE AND SLEET WILL CONTINUE OVERNIGHT... BEFORE
CHANGING TO DRIZZLE BETWEEN 12-15Z TUESDAY AT MOST SITES... WITH THE
EXCEPTION OF KFAY WHICH SHOULD REMAIN DRIZZLE/LIGHT RAIN THROUGH THE
DURATION. WINDS WILL REMAIN NE AROUND 8-10 KTS.
BEYOND THE 18Z VALID TAF PERIOD...ADVERSE AVIATION CONDITIONS...
PARTICULARLY IN IFR AND OCCASIONAL MVFR CEILINGS...AND AREAS OF
DRIZZLE AND SPOTTY LIGHT RAIN...SHOULD PERSIST INTO WEDNESDAY.
FINALLY ON WEDNESDAY...CEILINGS SHOULD GRADUALLY START TO LIFT...
ALTHOUGH IT SHOULD BE NOTED THAT ON SOME GUIDANCE THE CEILINGS OVER
THE NORTHWEST PIEDMONT MAY NOT IMPROVE MARKEDLY UNTIL INTO WEDNESDAY
NIGHT. IF WINDS LIGHTEN UP AS SKIES CLEAR...AT LEAST SOME LIGHT FOG
COULD DEVELOP WEDNESDAY NIGHT.
THURSDAY THROUGH FRIDAY...ANTICIPATE VFR CONDITIONS. LATE FRIDAY
NIGHT INTO SATURDAY...THERE IS THE POTENTIAL FOR AREAS OF SUB-VFR
CONDITIONS IN LOW CLOUDS AND SHOWERS...ALONG AND AHEAD OF A COLD
FRONT THAT WILL MOVE THROUGH THE REGION ON SATURDAY. COLDER HIGH
PRESSURE AND DRIER AIR THEN BUILD IN FROM THE NORTH SATURDAY NIGHT
INCREASING PROBABILITIES OF A RETURN TO WIDESPREAD VFR CONDITIONS.
&&
.CLIMATE...
THE RECORD LOW MAXIMUM TEMPERATURES FOR MARCH 18 (TUESDAY) ARE...
KGSO...36 DEGREES FROM 1961.
KRDU...36 DEGREES FROM 1892.
KFAY...41 DEGREES FROM 1998.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO NOON EDT
TUESDAY FOR NCZ011-026>028-040>043-073>077.
WINTER WEATHER ADVISORY UNTIL NOON EDT TUESDAY FOR NCZ007>010-
021>025-038-039.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...MWS/CBL
SHORT TERM...DJF
LONG TERM...ELLIS
AVIATION...SEC/DJF
CLIMATE...DJF
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
145 AM EDT TUE MAR 18 2014
.SYNOPSIS...
A WEDGE OF HIGH PRESSURE IS EXPECTED TO RESIDE OVER THE AREA THROUGH
WEDNESDAY...WHILE THE SOUTHEAST LOW MOVES OFF THE COAST TONIGHT INTO
WEDNESDAY. A COLD FRONT THROUGH THE AREA LATE WEDNESDAY AFTERNOON
INTO WEDNESDAY NIGHT.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1150 PM EDT MONDAY...
CONCERNS FOR ICING CONTINUE TO GROW ACROSS THE EASTERN NC PIEDMONT
COUNTIES AS MOISTURE FROM SE DEVELOPING COASTAL SYSTEM BACKS NWWD
INTO THIS REGION. ICING ACCUMULATIONS ON THE VERGE OF WARNING
CRITERIA AND IT HAS BEEN VERY TROUBLESOME. SEVERAL LOCATIONS IN
ROCKINGHAM AND CASWELL COUNTIES WITH ICE ACCUMULATIONS NEAR 1/4
INCH...BUT MOST AREAS JUST BELOW THIS. PER EARLIER HRRR...FEEL
THAT BULK OF THIS PCPN WILL END WITHIN THE NEXT TWO TO THREE HOURS...SO
A WARNING AT THIS POINT WOULD PROBABLY ADD LITTLE VALUE. SO WILL
STAY COURSE WITH STRONGLY WORDED ADVISORY WITH ACCUMULATIONS NEAR
1/4 INCH IN SOME AREAS. ELSEWHERE...FZDZ AND FZFG COVER THE
SITUATION WITH NO CHANGES NEEDED AT THIS TIME. HAVE HAD TO LOWER
TEMPERATURES A FEW DEGREES AGAIN THROUGHOUT THE NIGHT AS THIS
WEDGE IS HOLDING TOUGH.
AS OF 745 PM EDT MONDAY...
MULTIPLE WINTER WEATHER CONCERNS CONTINUE THIS EVENING.
FIRST...SOUTHEAST U.S. COASTAL SYSTEM RESULTING IN RETROGRADING
PRECIPITATION BACK INTO THE NC/SOUTHSIDE VA COUNTIES. HRRR MODEL
SEEMS TO HAVE THE BEST HANDLE ON THIS AS THE WRF DID NOT HAVE A
CLUE AND THE LARGER SYNOPTIC SCALE MODELS HANDLE IT POORLY. USING
THE HRRR AS A GUIDE...HAVE INCREASED POPS TO LIKELY INTO OUR NC
COUNTIES AND TOWARD MTV/DAN THROUGH 06Z...THEN TAPER BACK TO
LOW/MID CHC RANGE AFTER THAT. THE BIG CONCERN WITH THIS AREA OF
PCPN IS THE TEMPERATURE. CLASSIC...SIGNIFICANT WEDGE REMAINS IN
PLACE AND IS NOT GOING ANYWHERE...POSSIBLY UNTIL WED AFTERNOON.
WRF HAD US IN THE MID 40S THIS AFTERNOON...WHERE IN REALITY IT HAS
NOT BUDGED OUT OF THE MID 20S IN MANY AREAS. THE ENTIRE CWA IS
BELOW FREEZING AT THIS POINT AND WILL REMAIN SO UNTIL AT LEAST
MID-DAY TUE. THUS...ANY PCPN WILL BE FZRA OR SLEET. WARM NOSE TOO
DEEP AND DYNAMICS TOO WEAK FOR ANY SN. FOR WSW...HAVE SEPARATED
OUT SOUTHERN COUNTIES WHERE FZRA/SLEET MORE LIKELY FROM COUNTIES
FURTHER NORTH WHERE PCPN WILL LIKELY BE JUST FZDZ/FZFG. IN THE
WEST...COOP OBSERVER RECENTLY CALLED IN FROM WYTHE COUNTY
REPORTING SIGNIFICANT RIME ICING FROM FZFG AND NOTED THAT PREVIOUSLY
DRY SURFACES WERE COATED WITH ICE. HAVE ISSUED A FZFG ADVISORY
FOR ALL WESTERN COUNTIES NOT INCLUDED IN THE WSW. HAVE ENDED THAT
AT 14Z SINCE THESE ARE THE AREAS MORE LIKELY TO CREEP ABOVE 32F
SOONER ON THE WEST SIDE OF THE WEDGE.
AS OF 410 PM EDT MONDAY...
WINTER WEATHER ADVISORIES HAVE BEEN POSTED FOR THIS EVENING UNTIL
NOON WEDNESDAY FOR AREAS OF FREEZING RAIN AND FREEZING DRIZZLE
FOR MOST OF SOUTHWEST VIRGINIA AND NORTHWEST NORTH CAROLINA.
SFC HIGH CENTERED NEAR OTTAWA WITH A SFC RIDGE EXTENDING DOWN THE
LEE OF THE APPALACHIANS TO THE CAROLINA PIEDMONT. THIS STRONG
WEDGE/COLD AIR DAMMING WILL PERSIST THIS EVENING INTO TUESDAY. MID
AND HIGH LEVEL MOISTURE SHOULD LEAVE BY LATE AFTERNOON INTO THIS
EVENING LEAVING NO POTENTIAL FOR SNOW CRYSTALS IN THE CLOUDS. THERE
IS A SMALL WINDOW FOR A BRIEF PERIOD OF SNOW AND SLEET MAINLY ACROSS
SOUTHERN PORTIONS OF CWA THIS EVENING INTO TONIGHT. EXPECT LIGHT
FREEZING RAIN AND FREEZING DRIZZLE TO BE MAIN PTYPE TONIGHT INTO
TUESDAY. AREAS OF FOG WILL DEVELOP ALONG THE BLUE RIDGE
OVERNIGHT. IN GENERAL...ANY ICE WILL BE A TENTH OF AN INCH OR
LESS. PRECIPITATION AMOUNTS WILL BE LIGHT. THERE IS THE POTENTIAL
FOR BLACK ICE OVERNIGHT INTO WEDNESDAY. LOW TEMPERATURES TONIGHT
WILL RANGE FROM AROUND 20 DEGREES IN THE NORTHWEST MOUNTAINS TO
THE LOWER 30S IN THE PIEDMONT. ANOTHER STRONG DISTURBANCE MOVING
OFF THE CAROLINA COAST TUESDAY WITH SURFACE HIGH STRENGTHENING
OVER NEW ENGLAND...WILL SERVE TO REINFORCE THE WEDGE AND THE EAST
TO NORTHEAST FLOW. INCREASED POPS TUESDAY MAINLY IN THE EASTERN
UPSLOPE AREA. HIGHS ON TUESDAY ARE TRICKY. PLAYED HIGHS FROM THE
LOWER 30S ALONG BLUE RIDGE TO NEAR 50 DEGREES IN THE FAR WEST.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
AS OF 400 PM EDT MONDAY...
WEDGE OF VERY COOL HIGH PRESSURE WILL LIKELY PERSIST OVER MOST...IF
NOT ALL OF THE BLACKSBURG FORECAST AREA INTO/THROUGH WEDNESDAY AS
UPPER RIDGE BUILDS OVER EASTERN AND SOUTHEASTERN PORTION OF THE
NATION DOWNSTREAM OF APPROACHING TROF ADVANCING EAST FROM THE
NORTHERN PLAINS.
ABUNDANT MOISTURE TRAPPED UNDER A STEEP INVERSION IN THE LOWER 6K FT
OF THE TROPOSPHERE WILL ENSURE THAT TEMPERATURES OVER THE ENTIRE
FORECAST AREA REMAIN WELL BELOW NORMAL THROUGH THIS PERIOD...AND
ALSO WELL BELOW GUIDANCE...ESPECIALLY DURING THE DAYTIME PERIODS.
EAST TO SOUTHEAST LOWER TROPOSPHERIC FLOW AROUND THE PERIPHERY OF
THE SURFACE RIDGE TO THE NORTHEAST...AND ADVANCING LOW PRESSURE TO
THE WEST WILL RESULT IN FORCED ASCENT THROUGH A SATURATED LOWER
LAYER TO WRING OUT SPOTTY VERY LIGHT RAIN OR FREEZING
RAIN/DRIZZLE...MAXIMIZED ALONG AND MAINLY EAST OF THE BLUE RIDGE.
WARM NOSE AT TOP OF INVERSION LAYER SUFFICIENTLY ABOVE
FREEZING...AND WITH NO MID/HIGH LEVEL CLOUDS TO SUPPORT SEEDER-
FEEDER PROCESSES THROUGH DENDRITIC LEVEL...PRECIPITATION THIS TIME
AROUND WILL BE ALL LIQUID AS OPPOSED TO SNOW/SLEET.
OVERALL AMOUNTS OF MEASURABLE PRECIPITATION TUESDAY NIGHT INTO
WEDNESDAY WILL BE MEAGER...PERHAPS ONLY A FEW HUNDREDTHS OF AN INCH
IN MOST LOCATIONS...BUT STILL ENOUGH TO RESULT IN SOME GLAZING OF
ELEVATED EXPOSED SURFACES...AGAIN MAXIMIZED ACROSS THE EASTERN
FLANKS OF THE APPALACHIANS. AS A RESULT...MAY AGAIN HAVE TO POST
ANOTHER WINTER WEATHER ADVISORY IN SOME LOCATIONS FOR TUESDAY NIGHT
INTO WEDNESDAY MORNING...BUT WILL HOLD OFF UNTIL CURRENT HEADLINES
IN NEAR-TERM PERIOD EXPIRE SO AS TO NOT CONFUSE THE ISSUE...AND
HIGHLIGHT IN HAZARDOUS WEATHER OUTLOOK FOR NOW.
TROF AND ASSOCIATED COOL FRONT FORECAST TO SWEEP EAST THROUGH THE
BLACKSBURG FORECAST AREA BY/DURING WEDNESDAY NIGHT...POSSIBLY
PRECEDED AND ACCOMPANIED BY SOME BRIEF SPOTTY SHOWERS...MAINLY
ACROSS THE WESTERN FLANKS OF THE APPALACHIANS WEDNESDAY
AFTERNOON...GRADUALLY TRANSITIONING TO SOME UPSLOPE RAIN/SNOW
SHOWERS AS COLDER AIR FINALLY ARRIVES LATER WEDNESDAY NIGHT.
REGARDLESS...ARRIVAL OF COLD FRONT WILL ACTUALLY HELP TO SCOUR OUT
TENACIOUS COOL WEDGE OVER AREA...SUCH THAT TEMPERATURES MAY ACTUALLY
SPIKE WITH ONSET OF MIXING BEFORE TRAILING OFF AGAIN LATER WEDNESDAY
NIGHT.
SURFACE HIGH PRESSURE BUILDING INTO THE AREA FROM THE WEST THURSDAY
INTO THURSDAY NIGHT WILL RESULT IN CLEARING SKIES AND A RETURN TO
TEMPERATURES CLOSER TO SEASONAL AVERAGES.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 400 PM EDT SUNDAY...
MAINLY DRY AND SEASONAL WEATHER EXPECTED IN THE FRIDAY/FRIDAY NIGHT
TIME-FRAME AS SURFACE RIDGE MOVES OVER AND THEN TO THE EAST OF
THE FORECAST AREA.
APPROACH OF YET ANOTHER WAVE IN THE NORTHERN STREAM IS THEN SET TO
PUSH EAST/SOUTHEAST THROUGH THE REGION ON SATURDAY...LIKELY
PRECEDED AND ACCOMPANIED BY SCATTERED SHOWERS.
BELOW NORMAL TEMPERATURES...BUT WITH A RETURN TO DRY WEATHER IS THEN
EXPECTED TO RETURN TO MOST AREAS IN THE SUNDAY/MONDAY
TIME-FRAME...WITH PERHAPS THE EXCEPTION OF THE WESTERN FLANKS OF
THE APPALACHIANS...WHERE SOME UPSLOPING CLOUDS...AND POSSIBLY EVEN
SOME SPOTTY RAIN/SNOW SHOWERS ARE POSSIBLE INTO EARLY NEXT WEEK.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 135 AM EDT TUESDAY...
VERY STRONG WEDGE WILL REMAIN OVER THE REGION THROUGH TONIGHT.
CEILINGS WILL STAY IFR TO LIFR UNTIL MID TO LATE MORNING. AREAS OF
FREEZING FOG...FREEZING RAIN AND FREEZING DRIZZLE WILL RESULT IN
MVFR VISIBILITIES. EXPECTING CEILINGS TO LIFT TO MVFR FOR A FEW
HOURS THIS AFTERNOON. KBLF WILL BE NEAR THE FRINGE OF THE LOWER
CLOUDS AND WEDGE SO CONFIDENCE IS LOWER AS TO WHEN CEILINGS WILL
LIFT AND WHEN LOWER CEILINGS WILL DEVELOP AGAIN THIS EVENING. FOR
ALL OTHER TAF SITES...AROUND 00Z/8PM CEILINGS AND VISIBILITIES WILL
AGAIN LOWER TO IFR/LIFR VALUES. HOWEVER...PRECIPITATION WILL NOT
BE AS WIDESPREAD.
.EXTENDED AVIATION DISCUSSION...
VFR CONDITIONS ARE EXPECTED TO RETURN WEDNESDAY AFTERNOON AND
CONTINUE THROUGH FRIDAY. GUSTY WEST WINDS ARE EXPECTED WEDNESDAY
AFTERNOON AND EVENING. SUB VFR CONDITIONS MAY RETURN FOR THE
WEEKEND AS A CANADIAN COLD FRONT MOVES THROUGH THE REGION
ACCOMPANIED BY SHOWERS...THEN UPSLOPE FLOW AND COLDER
TEMPERATURES.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR VAZ011-
013>020-022>024-032>035-043>047-058-059.
FREEZING FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR VAZ007-
009-010-012.
NC...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR NCZ001>006-
018>020.
WV...FREEZING FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR
WVZ042>045.
&&
$$
SYNOPSIS...KK
NEAR TERM...KK/RAB
SHORT TERM...WERT
LONG TERM...WERT
AVIATION...AMS/RAB
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
931 AM MDT TUE MAR 18 2014
.CORRECTION TO UPDATE...
&&
.SHORT TERM...TIGHT PRESSURE GRADIENT CIRCLING A DEEPENING SFC/
850MB LOW IN EXTREME NORTHEAST COLORADO WILL CONTINUE TO GENERATE
STRONG NORTHERLY SFC WINDS ON THE PLAINS AND STRONG NORTHWEST WINDS
IN THE MTNS AND FOOTHILLS. CIRCULATION AROUND THIS TIGHTLY WOUND UP
CYCLONE WILL ALSO CONTINUE TO WRAP BANDS OF LIGHT TO MODERATE SNOW
SOUTHWARD OUT OF WYOMING AND DOWN ACROSS NORTHEAST COLORADO FOR MOST
OF THE DAY. MAIN BAND OF SNOW NOW OVER AND ALONG THE FRONT RANGE. A
BAND OF SNOW JUST PASSED OVER DIA WHERE IT BRIEFLY LOWERED THE VSBY
TO A QUARTER MILE. THIS SAME BAND OF SNOW WAS NOW PRODUCING A
SIMILAR REDUCTION TO VISIBILITY AT CENTENNIAL AIRPORT IN THE
SOUTHEAST DENVER METRO AREA. THEY TOO SHOULD SEE IMPROVEMENT IN VSBY
BEFORE NEXT HOUR. AROUND SUNRISE THIS MORNING...THE MIDNIGHT CREW
ISSUED A SHORT FUSED WINTER WEATHER FOR SNOW AND BLOWING SNOW FOR
ZONE 38 UP ALONG THE WYOMING BORDER. NORTHERLY WINDS WERE GUSTING
OVER 50 MPH UP THAT WAY CAUSING AREAS OF BLOWING SNOW AND VERY COLD
WIND CHILLS. MEANWHILE AT THE CENTER OF THE SFC LOW...PRECIP HAS YET
TO DEVELOP...BUT ITS ONLY A MATTER OF TIME. AS THE CYCLONE SLOWLY
SHIFTS EAST SO WILL THE BAND OF SNOW ALONG THE FRONT RANGE. BY LATE
MORNING...SHOULD SEE RAPIDLY DETERIORATING CONDITIONS ACROSS THE
NORTHEAST CORNER OF THE STATE WHERE A HIGH WIND WARNING AND A WINTER
WEATHER ADVISORY FOR SNOW AND BLOWING SNOW ARE CURRENTLY IN EFFECT.
TRAVEL IN THE CORNER COUNTIES COULD GET PRETTY UGLY FOR A TIME LATE
THIS MORNING AND EARLY THIS AFTERNOON WITH THE POTENTIAL FOR 1 TO
1.5 INCH PER HOUR SNOWFALL RATES. AS FOR THE HIGH COUNTRY...THIS
SYSTEM WILL LIKELY HAVE LESS OF AN IMPACT. STILL LOOKING FOR PERIODS
OF LIGHT TO MODERATE SNOW ALL DAY. THEREFORE WILL CONTINUE THE
WINTER WEATHER ADVISORY FOR THIS AREA WITH STRONG NORTHWESTERLY
WINDS CONTINUING TO PRODUCE AREAS OF BLOWING SNOW AND DIFFICULT
DRIVING CONDITIONS ESPLY ON THE HIGH MTN PASSES. OH YES...THE DUST
STORM WARNING FOR SOUTHERN LINCOLN COUNTY WILL ALSO REMAIN IN EFFECT
WITH THE POTENTIAL FOR GUSTS TO AROUND 60 MPH.
.AVIATION...PREVAILING MVFR CIGS TODAY WITH PERIODS OF IFR AND LIFR
CIGS AND VSBYS WITH PASSING LIGHT TO MODERATE SNOW SHOWERS FOR THE
REMAINDER OF THIS MORNING. DIFFICULT TO PIN DOWN THE EXACT TIME OF
THESE SHOWERS AS THEY ARE BEING MOVED ALONG BY STRONG NORTHERLY
TRANSPORT WINDS. DENVER AREA TERMINALS HAVE THE POTENTIAL TO PICK UP
AN INCH OF SNOW BEFORE NOON TODAY...MOST OF THAT SHOULD BE CONFINED
TO GRASSY SURFACES. AFTER 3 PM TODAY...CLOUD BASES SHOULD LIFT ABOVE
5000 FT AGL AS DRIER AIR BLOWS DOWN OFF THE FOOTHILLS. WINDS SHOULD
ALSO DECREASE IN SPEED LATE THIS AFTERNOON. BY EARLY THIS EVENING
DENVER AREA TERMINALS SHOULD BE VFR CONDITIONS WITH GRADUAL CLEARING
OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 730 AM MDT TUE MAR 18 2014/
UPDATE...
AVIATION...BAND OF SNOW IS DEVELOPING JUST NORTH OF AIRPORT.
VELOCITY DATA SHOWS WINDS UP TO 50 KTS JUST ABOVE THE SFC. IF
THIS WIND MIXES TO THE GROUND COULD SEE GUSTS FM 50-55 MPH AT DIA
FOR AN HOUR OR TWO.
PREV DISCUSSION... /ISSUED 651 AM MDT TUE MAR 18 2014/
UPDATE...
SHORT TERM...CDFNT IS MOVING QUICKLY SOUTHWARD ALONG THE FRONT
RANGE WITH GUSTS FM 40 TO 50 MPH BEHIND FNT. AM A LITTLE WORRIED
ABOUT LARGE AREA OF SNOW OVER SERN WY WHICH COULD MOVE SOUTH ACROSS
THE FNT RANGE BY MID TO LATE MORNING IF LOW LVL FLOW BECOMS MORE
NNE INSTEAD OF NNW. HAVE INCLUDED ZN 34 IN WINTER WEATHER ADVISORY
AS MTN CAMS SHOW QUITE A BIT OF SNOW AND BLOWING SNOW ALONG I-70.
AVIATION...FNT IS COMING INTO DIA SO SHOULD SEE WINDS INCREASE TO
20 TO 30 MPH WITH SOME GUSTS TO 40 MPH. LATEST RUC IS MORE
FAVORABLE FOR SNOW AT DIA THAN PREVIOUS RUNS SO THIS WILL HAVE TO
BE WATCHED IN LATER UPDATES.
PREV DISCUSSION... /ISSUED 354 AM MDT TUE MAR 18 2014/
SHORT TERM...AN UPPER LEVEL LOW WAS OVER SERN WY/WRN NEBRASKA
EARLY THIS MORNING AND WILL MOVE SE INTO NWRN KS BY EARLY AFTN
AND THEN MORE EASTWARD INTO NC KS BY LATE AFTN. MEANWHILE STG SFC
GRADIENT WILL BE OVER THE PLAINS AND THEN BEGIN TO WEAKEN BY LATE
AFTN.
APPEARS SOME HEAVIER SNOW MAY DVLP ON THE BACKSIDE OF THE UPPER LVL
LOW OVER THE FAR NERN PLAINS OF COLORADO FM MID MORNING THRU EARLY
AFTN WITH UP TO 4 INCHES POSSIBLE OVER PORTIONS OF LOGAN...SEDGWICK
AND PHILLIPS COUNTIES WITH LESSOR AMOUNTS ELSEWHERE OVER THE PLAINS.
IN ADDITION WITH GUSTY NORTH TO NORTHWEST WINDS OF 20 TO 35 MPH WITH
GUSTS TO 50 MPH AT TIMES COULD LEAD TO NEAR BLIZZARD CONDITIONS
FM STERLING TO JULESBURG FOR A FEW HOURS LATER THIS MORNING INTO
THE EARLY AFTN. AFTER COORDINATION WITH SURROUNDING OFFICES HAVE
DECIDED TO ISSUE A SNOW/BLOWING SNOW ADVISORY FOR ZONES
42...48..50 AND 51.
ELSEWHERE OVER NERN CO A COLD FNT WILL SWEEP ACROSS THE FRONT RANGE
URBAN CORRIDOR BY MID MORNING WITH NLY UPSLOPE FLOW DEVELOPING OVER
THE PALMER DIVIDE. THUS WILL SEE SOME ENHANCEMENT OF SNOW FM MID
MORNING INTO THE EARLY AFTN HOURS GENERALLY SOUTH OF DENVER WHICH
COULD LEAD TO AMOUNTS IN THE 2 TO 4 INCH RANGE. WITH GUSTY WINDS UP
TO 50 MPH AT TIMES MAY SEE NEAR BLIZZARD CONDITIONS AS WELL OVER
EASTERN DOUGLAS AND WRN AREAS OF ELBERT COUNTY.
MEANWHILE AS FAR AS HIGH WINDS STILL MAY SEE GUSTS UP TO 55 MPH AT
TIMES WHERE PREVIOUS HIGH WIND WARNING IN EFFECT HOWEVER BEST FOCUS
MAY END UP OVER ERN ELBERT AND LINCOLN COUNTIES. WILL LIKELY SEE A
LOT OF BLOWING DUST OVER PORTIONS OF CNTRL AND SRN LINCOLN COUNTY SO
HAVE ISSUED A DUST STORM WARNING THERE WHERE VISIBILITIES COULD DROP
TO ZERO AT TIMES.
IN THE MTNS OROGRAPHICS WILL BE FAVORABLE THIS MORNING WITH NW FLOW
BUT THEN BECOME MORE NNE BY AFTN WHICH WOULD END UP FAVORING THE ERN
SLOPES. WILL STILL SEE SOME BLOWING SNOW AND POOR VISIBILITIES THRU
MIDDAY SO WILL EXTEND WINTER WEATHER ADVISORY UNTIL 18Z.
AFTN HIGHS WILL BE MUCH COLDER TODAY WITH READINGS IN THE MID 30S TO
LOWER 40S OVER NERN CO. BY THIS EVENING DRIER AIR WILL SPREAD
ACROSS THE PLAINS WITH PCPN ENDING BY 00Z ALONG WITH DECREADING
WIND. IN THE MTNS SOME MOISTURE WILL LINGER UNTIL MIDNIGHT SO MAY
STILL SEE SOME LIGHT SNOW WITH ACTIVITY DECREASING AFTER 06Z.
LONG TERM...NORTHWESTERLY FLOW ALOFT IS PROGGED FOR THE CWA
WEDNESDAY AND WEDNESDAY NIGHT. THE ALOFT BECOMES ZONAL THURSDAY AND
THURSDAY NIGHT WITH SLIGHTLY HIGHER SPEEDS WITH A JET MAXIMUM TO
OUR IMMEDIATE NORTH. DOWNWARD SYNOPTIC SCALE ENERGY IS PROGGED FOR
THE FORECAST AREA WEDNESDAY THROUGH THURSDAY...WITH NEUTRAL QG
VERTICAL VELOCITY THURSDAY NIGHT. THE BOUNDARY LAYER FLOW IS
PROGGED TO BE NORMAL DIURNAL PATTERNS WITH A BIT OF DOWNSLOPING
MIXED IN WEDNESDAY THROUGH THURSDAY. SPEEDS ARE NOT SIGNIFICANT IN
MOST AREAS. BY THURSDAY NIGHT LATE...MOST OF THE MODELS HAVE A
COLD FRONT MOVE IN WITH UPSLOPE BEHIND IT. AS FAR AS MOISTURE
GOES...THERE IS A TAD LINGERING ON SOME MODELS EARLY WEDNESDAY
OTHERWISE MOISTURE IS FAIRLY SPARSE. JUST A BIT HERE AND THERE
IN THE UPPER AND MID LEVELS. EVEN BEHIND THE LATE THURSDAY NIGHT
COLD FRONT...THERE IS NOT MUCH LOW LEVEL UPSLOPE MOISTURE OVER THE
PLAINS BY 12Z FRIDAY MORNING. THERE IS NOTHING ON THE QPF FIELDS
WEDNESDAY THROUGH THURSDAY NIGHT. NO POPS FOR THE FOUR PERIOD. FOR
TEMPERATURES...WEDNESDAY`S HIGHS LOOK TO WARM-UP SOME 5-7 C OVER
TODAY`S HIGHS. THURSDAY`S READINGS WILL BE ANOTHER 4-7 C WARMER
THAN WEDNESDAY`S. FOR THE LATER DAYS...FRIDAY THROUGH MONDAY...
MODELS KEEP ZONAL FLOW OVER COLORADO THROUGH SUNDAY...WITH A WEAK
UPPER TROUGH AND NORTHWESTERLY FLOW ALOFT BEHIND IT FOR SUNDAY
NIGHT INTO MONDAY. FRIDAY IS PRETTY DRY...BUT THERE IS QUITE A BIT
OF MOISTURE PROGGED FRIDAY NIGHT INTO SATURDAY NIGHT. THE ECMWF IS
DRY SUNDAY...THE GFS IS NOT. MONDAY IS FAIRLY DRY ON BOTH MODELS.
WILL HAVE SOME MINOR POPS IN FOR SNOW IN THE MOUNTAINS FRIDAY
NIGHT THROUGH SUNDAY. NOTHING SIGNIFICANT RIGHT NOW.
AVIATION...WINDS HAVE BEEN WLY EARLY THIS MORNING HOWEVER A
STG CDFNT WAS MOVING INTO SERN WY WHICH SHOULD AFFECT THE AIRPORT
BY 13Z OR 14Z WITH NORTH WINDS INCREASING TO 20 TO 30 MPH WITH
SOME GUSTS TO 40 MPH POSSIBLE THRU THE AFTN. AT THIS TIME IT LOOKS
LIKE THE BEST CHC OF SNOW WILL STAY SOUTH OF DIA ALTHOUGH CAN NOT
COMPLETELY RULE OUT A PERIOD OF LIGHT SNOW FM 15Z-19Z WITH
ACCUMULATIONS ONE HALF INCH OR LESS. APA COULD GET AN INCH OR TWO
OF SNOW HOWEVER. WITH GUSTY WINDS COULD SEE SOME RESTRICTION TO
VISIBILITIES AS WELL.
BY 00Z ANY SNOW SHOULD BE OVER WITH WINDS GRADUALLY DECREASING AS
WELL. WINDS WILL BECOME DRAINAGE AFTER 06Z WITH VFR CONDITIONS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ042-044-
046>051.
WINTER WEATHER ADVISORY UNTIL 3 PM MDT THIS AFTERNOON FOR COZ042-
048-050-051.
WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY FOR COZ031-033-034-
038.
WINTER WEATHER ADVISORY UNTIL 3 PM MDT THIS AFTERNOON FOR COZ041.
DUST STORM WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ047.
&&
$$
SHORT TERM UPDATE...BAKER
LONG TERM....RJK
AVIATION UPDATE...BAKER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
730 AM MDT TUE MAR 18 2014
.UPDATE...
&&
.AVIATION...BAND OF SNOW IS DEVELOPING JUST NORTH OF AIRPORT.
VELOCITY DATA SHOWS WINDS UP TO 50 KTS JUST ABOVE THE SFC. IF
THIS WIND MIXES TO THE GROUND COULD SEE GUSTS FM 50-55 MPH AT DIA
FOR AN HOUR OR TWO.
&&
.PREV DISCUSSION... /ISSUED 651 AM MDT TUE MAR 18 2014/
UPDATE...
SHORT TERM...CDFNT IS MOVING QUICKLY SOUTHWARD ALONG THE FRONT
RANGE WITH GUSTS FM 40 TO 50 MPH BEHIND FNT. AM A LITTLE WORRIED
ABOUT LARGE AREA OF SNOW OVER SERN WY WHICH COULD MOVE SOUTH ACROSS
THE FNT RANGE BY MID TO LATE MORNING IF LOW LVL FLOW BECOMS MORE
NNE INSTEAD OF NNW. HAVE INCLUDED ZN 34 IN WINTER WEATHER ADVISORY
AS MTN CAMS SHOW QUITE A BIT OF SNOW AND BLOWING SNOW ALONG I-70.
AVIATION...FNT IS COMING INTO DIA SO SHOULD SEE WINDS INCREASE TO
20 TO 30 MPH WITH SOME GUSTS TO 40 MPH. LATEST RUC IS MORE
FAVORABLE FOR SNOW AT DIA THAN PREVIOUS RUNS SO THIS WILL HAVE TO
BE WATCHED IN LATER UPDATES.
PREV DISCUSSION... /ISSUED 354 AM MDT TUE MAR 18 2014/
SHORT TERM...AN UPPER LEVEL LOW WAS OVER SERN WY/WRN NEBRASKA
EARLY THIS MORNING AND WILL MOVE SE INTO NWRN KS BY EARLY AFTN
AND THEN MORE EASTWARD INTO NC KS BY LATE AFTN. MEANWHILE STG SFC
GRADIENT WILL BE OVER THE PLAINS AND THEN BEGIN TO WEAKEN BY LATE
AFTN.
APPEARS SOME HEAVIER SNOW MAY DVLP ON THE BACKSIDE OF THE UPPER LVL
LOW OVER THE FAR NERN PLAINS OF COLORADO FM MID MORNING THRU EARLY
AFTN WITH UP TO 4 INCHES POSSIBLE OVER PORTIONS OF LOGAN...SEDGWICK
AND PHILLIPS COUNTIES WITH LESSOR AMOUNTS ELSEWHERE OVER THE PLAINS.
IN ADDITION WITH GUSTY NORTH TO NORTHWEST WINDS OF 20 TO 35 MPH WITH
GUSTS TO 50 MPH AT TIMES COULD LEAD TO NEAR BLIZZARD CONDITIONS
FM STERLING TO JULESBURG FOR A FEW HOURS LATER THIS MORNING INTO
THE EARLY AFTN. AFTER COORDINATION WITH SURROUNDING OFFICES HAVE
DECIDED TO ISSUE A SNOW/BLOWING SNOW ADVISORY FOR ZONES
42...48..50 AND 51.
ELSEWHERE OVER NERN CO A COLD FNT WILL SWEEP ACROSS THE FRONT RANGE
URBAN CORRIDOR BY MID MORNING WITH NLY UPSLOPE FLOW DEVELOPING OVER
THE PALMER DIVIDE. THUS WILL SEE SOME ENHANCEMENT OF SNOW FM MID
MORNING INTO THE EARLY AFTN HOURS GENERALLY SOUTH OF DENVER WHICH
COULD LEAD TO AMOUNTS IN THE 2 TO 4 INCH RANGE. WITH GUSTY WINDS UP
TO 50 MPH AT TIMES MAY SEE NEAR BLIZZARD CONDITIONS AS WELL OVER
EASTERN DOUGLAS AND WRN AREAS OF ELBERT COUNTY.
MEANWHILE AS FAR AS HIGH WINDS STILL MAY SEE GUSTS UP TO 55 MPH AT
TIMES WHERE PREVIOUS HIGH WIND WARNING IN EFFECT HOWEVER BEST FOCUS
MAY END UP OVER ERN ELBERT AND LINCOLN COUNTIES. WILL LIKELY SEE A
LOT OF BLOWING DUST OVER PORTIONS OF CNTRL AND SRN LINCOLN COUNTY SO
HAVE ISSUED A DUST STORM WARNING THERE WHERE VISIBILITIES COULD DROP
TO ZERO AT TIMES.
IN THE MTNS OROGRAPHICS WILL BE FAVORABLE THIS MORNING WITH NW FLOW
BUT THEN BECOME MORE NNE BY AFTN WHICH WOULD END UP FAVORING THE ERN
SLOPES. WILL STILL SEE SOME BLOWING SNOW AND POOR VISIBILITIES THRU
MIDDAY SO WILL EXTEND WINTER WEATHER ADVISORY UNTIL 18Z.
AFTN HIGHS WILL BE MUCH COLDER TODAY WITH READINGS IN THE MID 30S TO
LOWER 40S OVER NERN CO. BY THIS EVENING DRIER AIR WILL SPREAD
ACROSS THE PLAINS WITH PCPN ENDING BY 00Z ALONG WITH DECREADING
WIND. IN THE MTNS SOME MOISTURE WILL LINGER UNTIL MIDNIGHT SO MAY
STILL SEE SOME LIGHT SNOW WITH ACTIVITY DECREASING AFTER 06Z.
LONG TERM...NORTHWESTERLY FLOW ALOFT IS PROGGED FOR THE CWA
WEDNESDAY AND WEDNESDAY NIGHT. THE ALOFT BECOMES ZONAL THURSDAY AND
THURSDAY NIGHT WITH SLIGHTLY HIGHER SPEEDS WITH A JET MAXIMUM TO
OUR IMMEDIATE NORTH. DOWNWARD SYNOPTIC SCALE ENERGY IS PROGGED FOR
THE FORECAST AREA WEDNESDAY THROUGH THURSDAY...WITH NEUTRAL QG
VERTICAL VELOCITY THURSDAY NIGHT. THE BOUNDARY LAYER FLOW IS
PROGGED TO BE NORMAL DIURNAL PATTERNS WITH A BIT OF DOWNSLOPING
MIXED IN WEDNESDAY THROUGH THURSDAY. SPEEDS ARE NOT SIGNIFICANT IN
MOST AREAS. BY THURSDAY NIGHT LATE...MOST OF THE MODELS HAVE A
COLD FRONT MOVE IN WITH UPSLOPE BEHIND IT. AS FAR AS MOISTURE
GOES...THERE IS A TAD LINGERING ON SOME MODELS EARLY WEDNESDAY
.OTHERWISE MOISTURE IS FAIRLY SPARSE. JUST A BIT HERE AND THERE
IN THE UPPER AND MID LEVELS. EVEN BEHIND THE LATE THURSDAY NIGHT
COLD FRONT...THERE IS NOT MUCH LOW LEVEL UPSLOPE MOISTURE OVER THE
PLAINS BY 12Z FRIDAY MORNING. THERE IS NOTHING ON THE QPF FIELDS
WEDNESDAY THROUGH THURSDAY NIGHT. NO POPS FOR THE FOUR PERIOD. FOR
TEMPERATURES...WEDNESDAY`S HIGHS LOOK TO WARM-UP SOME 5-7 C OVER
TODAY`S HIGHS. THURSDAY`S READINGS WILL BE ANOTHER 4-7 C WARMER
THAN WEDNESDAY`S. FOR THE LATER DAYS...FRIDAY THROUGH MONDAY...
MODELS KEEP ZONAL FLOW OVER COLORADO THROUGH SUNDAY...WITH A WEAK
UPPER TROUGH AND NORTHWESTERLY FLOW ALOFT BEHIND IT FOR SUNDAY
NIGHT INTO MONDAY. FRIDAY IS PRETTY DRY...BUT THERE IS QUITE A BIT
OF MOISTURE PROGGED FRIDAY NIGHT INTO SATURDAY NIGHT. THE ECMWF IS
DRY SUNDAY...THE GFS IS NOT. MONDAY IS FAIRLY DRY ON BOTH MODELS.
WILL HAVE SOME MINOR POPS IN FOR SNOW IN THE MOUNTAINS FRIDAY
NIGHT THROUGH SUNDAY. NOTHING SIGNIFICANT RIGHT NOW.
AVIATION...WINDS HAVE BEEN WLY EARLY THIS MORNING HOWEVER A
STG CDFNT WAS MOVING INTO SERN WY WHICH SHOULD AFFECT THE AIRPORT
BY 13Z OR 14Z WITH NORTH WINDS INCREASING TO 20 TO 30 MPH WITH
SOME GUSTS TO 40 MPH POSSIBLE THRU THE AFTN. AT THIS TIME IT LOOKS
LIKE THE BEST CHC OF SNOW WILL STAY SOUTH OF DIA ALTHOUGH CAN NOT
COMPLETELY RULE OUT A PERIOD OF LIGHT SNOW FM 15Z-19Z WITH
ACCUMULATIONS ONE HALF INCH OR LESS. APA COULD GET AN INCH OR TWO
OF SNOW HOWEVER. WITH GUSTY WINDS COULD SEE SOME RESTRICTION TO
VISIBILITIES AS WELL.
BY 00Z ANY SNOW SHOULD BE OVER WITH WINDS GRADUALLY DECREASING AS
WELL. WINDS WILL BECOME DRAINAGE AFTER 06Z WITH VFR CONDITIONS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ042-044-
046>051.
WINTER WEATHER ADVISORY UNTIL 3 PM MDT THIS AFTERNOON FOR COZ042-
048-050-051.
WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY FOR COZ031-033-034-
038.
WINTER WEATHER ADVISORY UNTIL 3 PM MDT THIS AFTERNOON FOR COZ041.
DUST STORM WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ047.
&&
$$
SHORT TERM...RPK
LONG TERM....RJK
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
651 AM MDT TUE MAR 18 2014
.UPDATE...
&&
.SHORT TERM...CDFNT IS MOVING QUICKLY SOUTHWARD ALONG THE FRONT
RANGE WITH GUSTS FM 40 TO 50 MPH BEHIND FNT. AM A LITTLE WORRIED
ABOUT LARGE AREA OF SNOW OVER SERN WY WHICH COULD MOVE SOUTH ACROSS
THE FNT RANGE BY MID TO LATE MORNING IF LOW LVL FLOW BECOMS MORE
NNE INSTEAD OF NNW. HAVE INCLUDED ZN 34 IN WINTER WEATHER ADVISORY
AS MTN CAMS SHOW QUITE A BIT OF SNOW AND BLOWING SNOW ALONG I-70.
.AVIATION...FNT IS COMING INTO DIA SO SHOULD SEE WINDS INCREASE TO
20 TO 30 MPH WITH SOME GUSTS TO 40 MPH. LATEST RUC IS MORE
FAVORABLE FOR SNOW AT DIA THAN PREVIOUS RUNS SO THIS WILL HAVE TO
BE WATCHED IN LATER UPDATES.
&&
.PREV DISCUSSION... /ISSUED 354 AM MDT TUE MAR 18 2014/
SHORT TERM...AN UPPER LEVEL LOW WAS OVER SERN WY/WRN NEBRASKA
EARLY THIS MORNING AND WILL MOVE SE INTO NWRN KS BY EARLY AFTN
AND THEN MORE EASTWARD INTO NC KS BY LATE AFTN. MEANWHILE STG SFC
GRADIENT WILL BE OVER THE PLAINS AND THEN BEGIN TO WEAKEN BY LATE
AFTN.
APPEARS SOME HEAVIER SNOW MAY DVLP ON THE BACKSIDE OF THE UPPER LVL
LOW OVER THE FAR NERN PLAINS OF COLORADO FM MID MORNING THRU EARLY
AFTN WITH UP TO 4 INCHES POSSIBLE OVER PORTIONS OF LOGAN...SEDGWICK
AND PHILLIPS COUNTIES WITH LESSOR AMOUNTS ELSEWHERE OVER THE PLAINS.
IN ADDITION WITH GUSTY NORTH TO NORTHWEST WINDS OF 20 TO 35 MPH WITH
GUSTS TO 50 MPH AT TIMES COULD LEAD TO NEAR BLIZZARD CONDITIONS
FM STERLING TO JULESBURG FOR A FEW HOURS LATER THIS MORNING INTO
THE EARLY AFTN. AFTER COORDINATION WITH SURROUNDING OFFICES HAVE
DECIDED TO ISSUE A SNOW/BLOWING SNOW ADVISORY FOR ZONES
42...48..50 AND 51.
ELSEWHERE OVER NERN CO A COLD FNT WILL SWEEP ACROSS THE FRONT RANGE
URBAN CORRIDOR BY MID MORNING WITH NLY UPSLOPE FLOW DEVELOPING OVER
THE PALMER DIVIDE. THUS WILL SEE SOME ENHANCEMENT OF SNOW FM MID
MORNING INTO THE EARLY AFTN HOURS GENERALLY SOUTH OF DENVER WHICH
COULD LEAD TO AMOUNTS IN THE 2 TO 4 INCH RANGE. WITH GUSTY WINDS UP
TO 50 MPH AT TIMES MAY SEE NEAR BLIZZARD CONDITIONS AS WELL OVER
EASTERN DOUGLAS AND WRN AREAS OF ELBERT COUNTY.
MEANWHILE AS FAR AS HIGH WINDS STILL MAY SEE GUSTS UP TO 55 MPH AT
TIMES WHERE PREVIOUS HIGH WIND WARNING IN EFFECT HOWEVER BEST FOCUS
MAY END UP OVER ERN ELBERT AND LINCOLN COUNTIES. WILL LIKELY SEE A
LOT OF BLOWING DUST OVER PORTIONS OF CNTRL AND SRN LINCOLN COUNTY SO
HAVE ISSUED A DUST STORM WARNING THERE WHERE VISIBILITIES COULD DROP
TO ZERO AT TIMES.
IN THE MTNS OROGRAPHICS WILL BE FAVORABLE THIS MORNING WITH NW FLOW
BUT THEN BECOME MORE NNE BY AFTN WHICH WOULD END UP FAVORING THE ERN
SLOPES. WILL STILL SEE SOME BLOWING SNOW AND POOR VISIBILITIES THRU
MIDDAY SO WILL EXTEND WINTER WEATHER ADVISORY UNTIL 18Z.
AFTN HIGHS WILL BE MUCH COLDER TODAY WITH READINGS IN THE MID 30S TO
LOWER 40S OVER NERN CO. BY THIS EVENING DRIER AIR WILL SPREAD
ACROSS THE PLAINS WITH PCPN ENDING BY 00Z ALONG WITH DECREADING
WIND. IN THE MTNS SOME MOISTURE WILL LINGER UNTIL MIDNIGHT SO MAY
STILL SEE SOME LIGHT SNOW WITH ACTIVITY DECREASING AFTER 06Z.
LONG TERM...NORTHWESTERLY FLOW ALOFT IS PROGGED FOR THE CWA
WEDNESDAY AND WEDNESDAY NIGHT. THE ALOFT BECOMES ZONAL THURSDAY AND
THURSDAY NIGHT WITH SLIGHTLY HIGHER SPEEDS WITH A JET MAXIMUM TO
OUR IMMEDIATE NORTH. DOWNWARD SYNOPTIC SCALE ENERGY IS PROGGED FOR
THE FORECAST AREA WEDNESDAY THROUGH THURSDAY...WITH NEUTRAL QG
VERTICAL VELOCITY THURSDAY NIGHT. THE BOUNDARY LAYER FLOW IS
PROGGED TO BE NORMAL DIURNAL PATTERNS WITH A BIT OF DOWNSLOPING
MIXED IN WEDNESDAY THROUGH THURSDAY. SPEEDS ARE NOT SIGNIFICANT IN
MOST AREAS. BY THURSDAY NIGHT LATE...MOST OF THE MODELS HAVE A
COLD FRONT MOVE IN WITH UPSLOPE BEHIND IT. AS FAR AS MOISTURE
GOES...THERE IS A TAD LINGERING ON SOME MODELS EARLY WEDNESDAY
..OTHERWISE MOISTURE IS FAIRLY SPARSE. JUST A BIT HERE AND THERE
IN THE UPPER AND MID LEVELS. EVEN BEHIND THE LATE THURSDAY NIGHT
COLD FRONT...THERE IS NOT MUCH LOW LEVEL UPSLOPE MOISTURE OVER THE
PLAINS BY 12Z FRIDAY MORNING. THERE IS NOTHING ON THE QPF FIELDS
WEDNESDAY THROUGH THURSDAY NIGHT. NO POPS FOR THE FOUR PERIOD. FOR
TEMPERATURES...WEDNESDAY`S HIGHS LOOK TO WARM-UP SOME 5-7 C OVER
TODAY`S HIGHS. THURSDAY`S READINGS WILL BE ANOTHER 4-7 C WARMER
THAN WEDNESDAY`S. FOR THE LATER DAYS...FRIDAY THROUGH MONDAY...
MODELS KEEP ZONAL FLOW OVER COLORADO THROUGH SUNDAY...WITH A WEAK
UPPER TROUGH AND NORTHWESTERLY FLOW ALOFT BEHIND IT FOR SUNDAY
NIGHT INTO MONDAY. FRIDAY IS PRETTY DRY...BUT THERE IS QUITE A BIT
OF MOISTURE PROGGED FRIDAY NIGHT INTO SATURDAY NIGHT. THE ECMWF IS
DRY SUNDAY...THE GFS IS NOT. MONDAY IS FAIRLY DRY ON BOTH MODELS.
WILL HAVE SOME MINOR POPS IN FOR SNOW IN THE MOUNTAINS FRIDAY
NIGHT THROUGH SUNDAY. NOTHING SIGNIFICANT RIGHT NOW.
AVIATION...WINDS HAVE BEEN WLY EARLY THIS MORNING HOWEVER A
STG CDFNT WAS MOVING INTO SERN WY WHICH SHOULD AFFECT THE AIRPORT
BY 13Z OR 14Z WITH NORTH WINDS INCREASING TO 20 TO 30 MPH WITH
SOME GUSTS TO 40 MPH POSSIBLE THRU THE AFTN. AT THIS TIME IT LOOKS
LIKE THE BEST CHC OF SNOW WILL STAY SOUTH OF DIA ALTHOUGH CAN NOT
COMPLETELY RULE OUT A PERIOD OF LIGHT SNOW FM 15Z-19Z WITH
ACCUMULATIONS ONE HALF INCH OR LESS. APA COULD GET AN INCH OR TWO
OF SNOW HOWEVER. WITH GUSTY WINDS COULD SEE SOME RESTRICTION TO
VISIBILITIES AS WELL.
BY 00Z ANY SNOW SHOULD BE OVER WITH WINDS GRADUALLY DECREASING AS
WELL. WINDS WILL BECOME DRAINAGE AFTER 06Z WITH VFR CONDITIONS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY FOR COZ031-033-34.
HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ042-044-
046>051.
WINTER WEATHER ADVISORY UNTIL 3 PM MDT THIS AFTERNOON FOR COZ042-
048-050-051.
WINTER WEATHER ADVISORY UNTIL 3 PM MDT THIS AFTERNOON FOR COZ041.
DUST STORM WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ047.
&&
$$
SHORT TERM...RPK
LONG TERM....RJK
AVIATION...RPK
Area Forecast Discussion
National Weather Service Lincoln IL
1100 AM CDT Tue Mar 18 2014
.DISCUSSION...
ISSUED 1053 AM CDT Tue Mar 18 2014 by NWS Chicago
Main forecast tweaks for the afternoon were to the diurnal
temperature and dewpoint curves. Did not really change overall
highs but slowed the warming a bit in the east and southeast to
account for lingering cloud cover and better blend with trends
shown by the neighbors. Mid 50s highs will not come from advecting
cold air from under the cloudiness to the southeast, but from
lifting the low out of Kansas and pushing the warm and clear
sector over the area later today. May also need to update sky
grids as well to reflect this progression.
No changes to later periods at this time.
Lenning
&&
.AVIATION...
ISSUED 635 AM CDT Tue Mar 18 2014
Forecast concern will be movement of MVFR/IFR cigs over southern
Indiana this morning and how far west and northwest they move
this morning. Past few runs of the RAP and HRRR models suggest
our eastern TAF sites (KDEC and KCMI) may be affected by MVFR cigs
after 19z this afternoon. Otherwise, the remainder of the sites
will remain VFR thru the day. Look for increasing southeast to
south winds today with gusts up to 25 kts at times this afternoon.
A cold front will begin to approach the area tonight with winds
veering more into a south to southwest direction and decreasing in
speed later this evening. Because of the decrease in winds near
the surface, we may need to consider low level wind shear as winds
just off the surface will be from a 190-220 direction at around 40
kts. For now, will hold off including LLWS for this evening as
there is still some doubt how quickly sfc winds will diminish, if
at all, this evening. As the front moves across the area later
this evening, showers will increase some over the north with the
possibility for some isold TSRA. Will include VCTS at PIA, BMI and
CMI later this evening. Surface winds will veer more into the
southwest late tonight with speeds of 10 to 15 kts aftr 09z with
probabilities increasing for MVFR cigs as the storm system shifts
off to our northeast towards dawn Wednesday.
Smith
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Tue Mar 18 2014
SHORT TERM...Today through Friday night
00Z models are in fair agreement next few days and will use a
blend. One wx system to bring chance of rain showers tonight & Wed
with another one on tap for Fri and Fri night. A 3rd system
arrives Mon afternoon & Monday night with chance of rain/snow.
Extended models continue to trend colder during next work week
with coldest air arriving next Wed when 850 mb temps low to -15 to -20C.
CPC 8-14 day outlook for Mar 25-31 continue a 70% chance of below
normal temps over central IL with MN/WI/MI greater than 80% chance
of below normal temps. Central IL also has a 50% chance of above
normal precipitation. So winter like weather that develops during
next work week could linger through the rest of the month.
Strong 990 mb surface low pressure over central KS to lift ne
across northern IL overnight and across lower MI during Wed. This
to bring a cold front east across IL overnight. Increasing
sse winds ahead of approaching low pressure today with gusts to 30
mph this afternoon to warm temps into mid to upper 50s. Temps
currently are in the upper 20s and lower 30s. Models have trended
a few degrees cooler due to more mid/high clouds increasing from
the west today. Low stratus clouds should stay se of IL over KY
and southeast IN.
Have chance of rain showers spreading east across central IL
during the evening and into southeast IL by overnight. Added
isolated thunderstorms to northern areas tonight per SPC day 1
outlook with general risk of thunder over parts of central IL.
Models have trended slower and linger some light qpf over central
IL Wed with upper level trof moving into IL behind the cold front.
Have therefore increase chances of light rain showers Wed
especially from I-74 ne. Areas from Peoria north could see a few
light snow showers too Wed morning but no accumulations. Windy on
Wed with wsw wind gusts of 30 to 40 mph. If clouds break up during
the afternoon Wed could see higher wind gusts.
Dry conditions Wed night and Thu with highs in the 50s Thu with
more sunshine and increasing south winds Thu afternoon as high
pressure passes to the east of IL.
Nice warmup on Friday still expected with highs in the upper 50s
to mid 60s with breezy ssw winds and mildest temps in southeast IL.
Surface low pressure to track into central/northern IL Friday
afternoon and brings another cold front east through IL then with
next chance of rain showers Friday and Friday night. Have isolated
thunder over southeast IL Friday night.
LONG TERM...Saturday through Wednesday
Dry and cooler conditions expected this weekend. A 3rd wx system
to affect region Mon afternoon and Monday night with chance of
rain or snow showers and turning progressively colder from Mon
thru Wed.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
906 AM CDT TUE MAR 18 2014
.DISCUSSION...
312 AM CDT
OTHER THAN TODAY...EARLY WEDNESDAY MORNING...AND POTENTIALLY FRIDAY
(ESPECIALLY SOUTHERN CWA) THE UNRELENTING WINTER OF 2013-14 LOOKS
POISED TO KEEP GOING AD NAUSEUM.
PAIR OF LOW PRESSURES OVER THE CENTRAL AND SOUTHERN PLAINS WILL
CONSOLIDATE INTO A SINGLE FAIRLY DEEP LOW THAT WILL TRACK EAST
TOWARD KANSAS CITY BY EARLY EVENING. WARM AIR ADVECTION WILL
CONTINUE AND SHOULD RESULT IN A MILDER DAY TODAY...THOUGH EASTERLY
COMPONENT TO THE WINDS SHOULD RESULT IN COOLER CONDITIONS NEAR THE
CHICAGO LAKE FRONT AND NORTH SHORE. HIGH AND EVENTUALLY MID
CLOUDINESS WILL BE ON THE INCREASE TODAY BUT STILL SOME FILTERED
SUNSHINE IS EXPECTED...ESPECIALLY THIS MORNING.
SFC LOW WILL TRACK NE TO NEAR MKX BY 12Z WEDNESDAY...RESULTING IN
WINDS BECOMING SOUTH THIS EVENING WHICH WILL SHOVE THE MARINE LAYER
OFFSHORE LIKELY ALLOWING IL LAKESIDE AREAS TO REACH THEIR HIGH TEMPS
FOR THE DAY WELL AFTER DARK TONIGHT. THE SYSTEM TONIGHT WILL NOT
REALLY HAVE ACCESS TO GULF MOISTURE AS IT MOVES THROUGH...HOWEVER
COMBINATION OF COLD AIR ALOFT AND RESULTANT STEEP LAPSE RATES AND
STRONG LOW LEVEL JET THAT WILL BECOME COUPLED WITH THE LEFT EXIT
REGION OF 120-130KT 250MB JET SHOULD ALLOW FOR STRONG ASCENT. WOULD
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO BREAK OUT THIS EVENING
AND MOVE ACROSS THE CWA LATE THIS EVENING AND PARTICULARLY
OVERNIGHT.
SOME SHOWERS COULD LINGER INTO WEDNESDAY MORNING AS THE COLD FRONT
MOVES ACROSS THE AREA RESULTING IN WEDNESDAY TURNING BLUSTERY AND
COLDER WITH STEADY/SLOWLY FALLING TEMPS DURING THE DAY. LINGERING
LOW LEVEL MOISTURE AND STEEPENING LOW LEVEL LAPSE RATES COULD ALLOW
FOR SOME FLURRIES OR LIGHT SNOW SHOWERS WEDNESDAY AFTERNOON BUT NOT
ANTICIPATING ANY ACCUMULATION.
CONTINUED BELOW AVERAGE TEMPS EXPECTED THROUGH THURSDAY NIGHT. A
COUPLE OF FAIRLY LOW AMPLITUDE NW FLOW SHORTWAVE EXPECTED TO RIPPLE
ACROSS THE REGION THURSDAY NIGHT THROUGH FRIDAY NIGHT. THE SECOND
SYSTEM...ARRIVING FRIDAY AFTERNOON AND EVENING...LOOKS TO BE A BIT
MORE AMPLIFIED AND STANDS A BETTER CHANCE TO BRING SOME
PRECIPITATION TO THE AREA. ECMWF CONTINUES TO BE AT ODDS WITH THE
GFS/GEM REGARDING THE TRACK OF THE SFC LOW ON FRIDAY. FARTHER NORTH
TRACK DEPICTED BY GEM/GFS WOULD OFFER UP A DECENT CHANCE OF MOST OF
THE CWA BRIEFLY GETTING INTO THE WARM SECTOR AND ALLOWING TEMPS TO
REACH IF NOT GET A BIT ABOVE NORMAL. ECMWF TRACKS SFC LOW FARTHER
SOUTH AND WOULD KEEP WINDS OFF THE LAKE AND RESULT IN MUCH COLDER
TEMPS FRIDAY NORTH OF I-80. THE TRACK DIFFERENCES BETWEEN THE MODELS
IS SMALL AND REALLY LITTLE MORE THAN NOISE...BUT HAVE DRAMATICALLY
DIFFERENT RESULTS IN SENSIBLE WEATHER...PARTICULARLY OVER NORTHEAST
ILLINOIS. GOING TO SIDE WITH CLIMO AND KEEP TEMPS COLDER OVER
NORTHEAST ILLINOIS...BUT BUST POTENTIAL IS HIGH AND IF TRACK ENDS UP
BEING FARTHER NORTH THEN WE COULD BE PLEASANTLY SURPRISED WITH
MILDER TEMPERATURES. AT THIS POINT...SOUTHERN CWA LOOKS LIKELY TO BE
IN THE WARM SECTOR WITH HIGHS WELL INTO THE 50S.
THE FIRST OFFICIAL WEEKEND OF SPRING LOOKS TO BE ANYTHING BUT
SPRING-LIKE WITH UNSEASONABLY COLD AIR MOVING IN BEHIND THE SYSTEM
FRIDAY NIGHT INTO SATURDAY. THAT COLD BLAST LOOKS TO BE FOLLOWED UP
WITH AN EVEN COLDER AIR MASS WITH SECONDARY COLDER FRONT SUNDAY WITH
ECMWF/GFS/GFS ENSEMBLES AND GEM ALL BRINGING 850MB TEMPS DOWN INTO
THE -16 TO -19C RANGE SUNDAY AFTERNOON. LOOKING BACK AT REANALYSIS
DATA GOING BACK TO 1979...850MB TEMPS OF -16 OR COLDER WOULD BE
AMONG THE COLDEST 1 PERCENT OF READINGS FOR MAR 16-31ST...SO QUITE
IMPRESSIVE. HAVE SCALED BACK HIGHS A COUPLE DEGREES FROM MODEL
BLENDED INITIALIZATION...BUT WORTH NOTING THAT 4 OUT OF THE 6
PREVIOUS DAYS WITH 850MB TEMPS OF -16C OR COLDER IN LATE MARCH HAS
RESULTED IN HIGHS IN THE 20S IN CHICAGO AND THE OTHER 2 DAYS WERE
LOW 30S.
GFS/ECMWF CONTINUE TO ADVERTISE A NORTHWEST FLOW SHORT WAVE ARRIVING
AROUND MONDAY WHICH COULD BRING SNOW TO THE AREA...ONLY TO BE
FOLLOWED UP WITH LONG RANGE MODELS SUGGEST WILL BE AN EVEN COLDER
BLAST OF AIR NEXT WEEK. WHILE ITS STILL BEYOND THE 7 DAY FORECAST
PERIOD...RUN AFTER RUN THE ECMWF HAS BEEN ADVERTISING AN ARCTIC
BLAST THAT COULD POTENTIALLY THREATEN RECORDS NEXT WEEK AND NOW THE
GFS HAS JOINED THIS BAND CAMP. GIVEN THE STRONG AGREEMENT IN THE
MEDIUM RANGE MODELS AND THEIR ENSEMBLES IN DEVELOPING A STRONG REX
BLOCK OVER THE NORTHEAST PACIFIC NORTH INTO ALASKA THIS WEEKEND IT
WOULD SEEM TO BE HIGHLY LIKELY THAT GENERALLY MUCH BELOW AVERAGE
TEMPS WOULD CONTINUE THROUGH THE REST OF MARCH.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* GUSTY SE TO E WINDS TODAY.
* RAIN SHOWERS LIKELY AFT 06Z TONIGHT.
* CHANCE OF EMBEDDED TSRA MAINLY 08Z-11Z TONIGHT.
* LOWER MVFR TO IFR CIGS LIKELY WITH THE RAIN LATE TONIGHT.
ED F
//DISCUSSION...UPDATED 12Z...
THE MAIN FORECAST CONCERNS DURING THE DAY TODAY WILL AGAIN BE THE
WINDS. A POTENT AREA OF LOW PRESSURE...CURRENTLY CENTERED ACROSS
THE PLAINS STATES...WILL BEGIN TO CONSOLIDATE AND TREK EASTWARD
ACROSS THE LOWER AND MID MISSOURI VALLEY LATER TODAY. THIS WILL
FAVOR AN EAST-SOUTHEASTERLY WIND COMPONENT...WITH GUSTS UP AROUND
20 KT...AT ALL THE TAF SITES THROUGH THE DAY.
THIS AREA OF SURFACE LOW PRESSURE...AND THE ACCOMPANYING MID LEVEL
DISTURBANCE WILL MOVE ACROSS NORTHERN ILLINOIS LATE TONIGHT
INTO EARLY WEDNESDAY MORNING. THIS TIMING CONTINUES TO FAVOR THE BEST
CHANCES FOR RAIN SHOWERS AND IFR CIGS ACROSS NORTHERN
ILLINOIS...MAINLY AFTER MIDNIGHT TONIGHT. THE MAIN CHANGE FOR THE
12 UTC TAFS WAS TO ADD A PROB 30 MENTION FOR SOME THUNDER LATER
TONIGHT. GIVEN THE COMBINATION OF SOME STEEP MID LEVEL LAPSE RATES
AND A PERIOD OF GOOD DYNAMIC FORCING FOR ASCENT WITHIN THE WARM
SECTOR OF THIS SYSTEM...IT APPEARS THAT SOME THUNDERSTORMS ARE
CERTAINLY POSSIBLE.
OTHERWISE...THE MAIN CONCERN LATER WEDNESDAY MORNING WILL BE THE ONSET
OF SOME STRONGER WESTERLY WINDS IN THE WAKE OF A COLD FRONTAL
PASSAGE...LIKELY BY LATE MORNING ON WEDNESDAY. IT APPEARS THAT THE WINDS
COULD GUST IN THE 30 TO 35 KT RANGE FOR A PERIOD WEDNESDAY
AFTERNOON FOLLOWING THIS COLD FRONTAL PASSAGE. THE MAIN PRECIP
THREAT SHOULD END DURING THE MORNING...WITH GRADUALLY IMPROVING CIGS
INTO THE AFTERNOON.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM TO HIGH FOR WIND FORECAST AND RAIN SHOWER TIMING.
* LOW TO MEDIUM FOR A THUNDERSTORM IMPACTING THE TERMINALS AFTER
08 UTC WED.
ED F
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED
12Z...
WEDNESDAY NIGHT...BECOMING VFR.
THURSDAY...VFR.
FRIDAY...CHANCE OF -RA. MVFR CIGS POSSIBLE.
SATURDAY THROUGH SUNDAY...VFR.
MONDAY...CHANCE OF SNOW AND IFR.
KJB
&&
.MARINE...
328 AM CDT
THE MAIN FORECAST CONCERNS OVER THE LAKE CONTINUE TO CENTER AROUND
THE STORM SYSTEM EXPECTED TO MOVE ACROSS LAKE MICHIGAN WEDNESDAY
MORNING.
WINDS WILL CONTINUE OUT OF THE EAST ACROSS THE NORTHERN END OF THE
LAKE TODAY...WITH SOUTHEASTERLY WINDS EXPECTED TO CONTINUE ACROSS
THE SOUTHERN END OF THE LAKE. WIND SPEEDS APPEAR TO BE IN THE 15 TO
25 KT RANGE...WITH SOME GUSTS POSSIBLY APPROACHING 30 KT LATER TODAY
AND TONIGHT...ESPECIALLY ACROSS SOUTHERN LAKE MICHIGAN. THIS
SOUTHEASTERLY WIND COMPONENT WILL LIKELY ALLOW WAVES TO CONTINUE TO
BUILD TO AND JUST ABOVE 4 FT ACROSS MY FAR NORTHERN MARINE NEAR
SHORE ZONES ACROSS NORTHERN ILLINOIS. THEREFORE...I HAVE ISSUED A
SMALL CRAFT ADVISORY STARTING THIS AFTERNOON FOR AREAS FROM CHICAGO
NORTHWARD.
FOR THE REMAINDER OF MY NEAR SHORE ZONES I WILL START THE
ADVISORY LATER TONIGHT...AS THE WINDS PICK UP OUT OF THE
SOUTH-SOUTHWEST TOWARDS WEDNESDAY MORNING...IN RESPONSE TO THE
APPROACHING AREA OF LOW PRESSURE. THE SYSTEMS COLD FRONT IS THEN
EXPECTED TO PUSH ACROSS THE NEAR SHORE ZONES...ALONG WITH MUCH OF
SOUTHERN LAKE MICHIGAN DURING THE MORNING ON WEDNESDAY. IN THE WAKE
OF THIS FRONTAL PASSAGE...WINDS WILL BECOME WESTERLY AND INCREASE UP
AROUND 30 KT FOR THE REST OF THE DAY. I AM STILL CONCERNED THAT
THERE COULD BE SOME LOW END GALES AT TIMES DURING THIS
PERIOD...ESPECIALLY DIRECTLY IN THE WAKE OF THE FRONTAL PASSAGE.
THIS THREAT STILL ALSO APPEARS TO BE PRIMARILY ACROSS THE SOUTHERN
HALF OF THE LAKE. AT THIS TIME...I WILL MENTION THE POSSIBILITY FOR
SOME GALE FORCE GUSTS...RATHER THAN GOING WITH A GALE WATCH...AS IT
APPEARS THE GALE GUSTS MAY END UP BEING FAIRLY SHORT LIVED IN THE
WAKE OF THE COLD FRONT.
THE WINDS WILL GRADUALLY ABATE WEDNESDAY NIGHT INTO THURSDAY AS THE
STORM SYSTEM CONTINUES NORTHEASTWARD INTO CANADA. A PERIOD OF
LIGHTER WINDS WILL ENSUE AS A SURFACE RIDGE OF HIGH PRESSURE PUSHES
ACROSS THE LAKE ON THURSDAY. A SECOND STORM SYSTEM STILL LOOKS TO
IMPACT WINDS ACROSS THE LAKE LATER IN THE WEEK...WITH ANOTHER PERIOD
OF HIGHER NORTHERN WINDS POSSIBLE INTO THE FIRST PART OF THE
WEEKEND.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741...5 PM TUESDAY TO 10 PM
WEDNESDAY.
SMALL CRAFT ADVISORY...LMZ744-LMZ745...1 AM WEDNESDAY TO 4 AM
THURSDAY.
SMALL CRAFT ADVISORY...LMZ742-LMZ743...1 AM WEDNESDAY TO 10 PM
WEDNESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
645 AM CDT Tue Mar 18 2014
.DISCUSSION...
ISSUED 330 AM CDT Tue Mar 18 2014
SHORT TERM...Today through Friday night
00Z models are in fair agreement next few days and will use a
blend. One wx system to bring chance of rain showers tonight & Wed
with another one on tap for Fri and Fri night. A 3rd system
arrives Mon afternoon & Monday night with chance of rain/snow.
Extended models continue to trend colder during next work week
with coldest air arriving next Wed when 850 mb temps low to -15 to -20C.
CPC 8-14 day outlook for Mar 25-31 continue a 70% chance of below
normal temps over central IL with MN/WI/MI greater than 80% chance
of below normal temps. Central IL also has a 50% chance of above
normal precipitation. So winter like weather that develops during
next work week could linger through the rest of the month.
Strong 990 mb surface low pressure over central KS to lift ne
across northern IL overnight and across lower MI during Wed. This
to bring a cold front east across IL overnight. Increasing
sse winds ahead of approaching low pressure today with gusts to 30
mph this afternoon to warm temps into mid to upper 50s. Temps
currently are in the upper 20s and lower 30s. Models have trended
a few degrees cooler due to more mid/high clouds increasing from
the west today. Low stratus clouds should stay se of IL over KY
and southeast IN.
Have chance of rain showers spreading east across central IL
during the evening and into southeast IL by overnight. Added
isolated thunderstorms to northern areas tonight per SPC day 1
outlook with general risk of thunder over parts of central IL.
Models have trended slower and linger some light qpf over central
IL Wed with upper level trof moving into IL behind the cold front.
Have therefore increase chances of light rain showers Wed
especially from I-74 ne. Areas from Peoria north could see a few
light snow showers too Wed morning but no accumulations. Windy on
Wed with wsw wind gusts of 30 to 40 mph. If clouds break up during
the afternoon Wed could see higher wind gusts.
Dry conditions Wed night and Thu with highs in the 50s Thu with
more sunshine and increasing south winds Thu afternoon as high
pressure passes to the east of IL.
Nice warmup on Friday still expected with highs in the upper 50s
to mid 60s with breezy ssw winds and mildest temps in southeast IL.
Surface low pressure to track into central/northern IL Friday
afternoon and brings another cold front east through IL then with
next chance of rain showers Friday and Friday night. Have isolated
thunder over southeast IL Friday night.
LONG TERM...Saturday through Wednesday
Dry and cooler conditions expected this weekend. A 3rd wx system
to affect region Mon afternoon and Monday night with chance of
rain or snow showers and turning progressively colder from Mon
thru Wed.
07
&&
.AVIATION...
ISSUED 635 AM CDT Tue Mar 18 2014
Forecast concern will be movement of MVFR/IFR cigs over southern
Indiana this morning and how far west and northwest they move
this morning. Past few runs of the RAP and HRRR models suggest
our eastern TAF sites (KDEC and KCMI) may be affected by MVFR cigs
after 19z this afternoon. Otherwise, the remainder of the sites
will remain VFR thru the day. Look for increasing southeast to
south winds today with gusts up to 25 kts at times this afternoon.
A cold front will begin to approach the area tonight with winds
veering more into a south to southwest direction and decreasing in
speed later this evening. Because of the decrease in winds near
the surface, we may need to consider low level wind shear as winds
just off the surface will be from a 190-220 direction at around 40
kts. For now, will hold off including LLWS for this evening as
there is still some doubt how quickly sfc winds will diminish, if
at all, this evening. As the front moves across the area later
this evening, showers will increase some over the north with the
possibility for some isold TSRA. Will include VCTS at PIA, BMI and
CMI later this evening. Surface winds will veer more into the
southwest late tonight with speeds of 10 to 15 kts aftr 09z with
probabilities increasing for MVFR cigs as the storm system shifts
off to our northeast towards dawn Wednesday.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1030 AM EDT TUE MAR 18 2014
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 AM EDT TUE MAR 18 2014
AFTER A DRY MILD DAY TODAY...RAIN SHOWERS WILL DEVELOP LATE TONIGHT
INTO WEDNESDAY AS A COLD FRONT MOVES THROUGH. COOLER DRIER WEATHER
IS EXPECTED FOR WEDNESDAY NIGHT AND THURSDAY. TEMPERATURES WILL ONCE
AGAIN TURN WARMER FOR FRIDAY WITH THE PASSAGE OF A WARM FRONT. RAIN
AND EMBEDDED THUNDERSTORMS WILL ACCOMPANY THE PASSAGE OF LOW
PRESSURE FRIDAY NIGHT. HIGH PRESSURE THEN REESTABLISHES FOR THE
WEEKEND WITH DRY AND PROGRESSIVELY COLDER AIR.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1008 AM EDT TUE MAR 18 2014
AREA OF LOW CLOUDS OVER SOUTHERN INDIANA HAS BEEN EXPANDING
NORTHWEST DURING THE PAST FEW HOURS. PILOT REPORTS INDICATE THIS
CLOUD DECK IS QUITE THIN...SO EXPECTING THESE CLOUDS TO SCATTER OUT
THIS AFTERNOON. THINK PARTLY CLOUDY WILL STILL WORK OVERALL
TODAY...BUT THERE WILL PROBABLY BE A PERIOD OF MAINLY CLOUDY SKIES
THROUGH EARLY AFTERNOON...ESPECIALLY OVER THE SOUTHERN THROUGH WEST
CENTRAL ZONES.
THIS MORNING/S UPPER AIR SUGGEST TODAY/S HIGHS ARE WITHIN
REACH...BUT THEY WILL DEPEND ON HOW FAST LOW CLOUDS DISSIPATE. WILL
NOT MAKE ANY CHANGES AT THIS TIME...BUT THE HIGHS MAY NEED TO BE
LOWERED LATER TODAY WHEN LOW CLOUD TRENDS BECOME MORE APPARENT.
PREVIOUS DISCUSSION FOLLOWS.
HIGH CLOUDS DRIFTING THROUGH EARLY THIS MORNING WITH WEAK HIGH
PRESSURE ACROSS THE OHIO VALLEY. LARGE AREA OF STRATUS MOVING W/NW
ACROSS KENTUCKY AS WELL. WITH LIGHT E/SE FLOW...TEMPS RANGED FROM
THE MID 20S TO LOWER 30S ACROSS THE FORECAST AREA AT 07Z.
INITIAL ISSUE FOCUSES ON THE STRATUS DECK EXPANDING TOWARDS THE
FORECAST AREA FROM THE SOUTHEAST. SHORT RANGE MODEL GUIDANCE
ADVECTING DEEPER MOISTURE INTO THE REGION THROUGH THE MORNING AS
LOW LEVEL FLOW VEERS TO A S/SE DIRECTION. AT THE SAME TIME...BOTH
THE RAP AND NAM APPEAR TO BE OVERDOING MOISTURE ON THE 925/950 MB
LEVELS VERSUS THE LEADING EDGE OF THE CURRENT STRATUS DECK AS OF
07Z. CONFIDENCE IS GROWING IN LOWER CLOUDS REACHING THE SOUTHEASTERN
PORTIONS OF THE FORECAST AREA OVER THE NEXT FEW HOURS...AND POSSIBLY
GETTING AS FAR NORTH AS I-70 OVER THE EASTERN HALF OF CENTRAL
INDIANA AFTER DAYBREAK. WILL INCREASE CLOUD COVERAGE GRIDS SOUTHEAST
OF THE INDY METRO FOR THE MORNING AND MONITOR FOR ANY ADDITIONAL
UPDATES OVER THE NEXT FEW HOURS.
ELSEWHERE ACROSS CENTRAL INDIANA...MID AND HIGH LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN ADVANCE OF LOW PRESSURE
TRACKING THROUGH THE CENTRAL PLAINS. EXPECT AN INCREASE IN SURFACE
WINDS BY THIS AFTERNOON AS THE LOW APPROACHES...WITH SUSTAINEDS TO
NEAR 15MPH BY LATE DAY.
TEMPS...EVENTUAL EXTENT OF STRATUS DECK BOTH IN COVERAGE AND TIME
WILL BE CRITICAL...AS THEY WERE ON MONDAY...ON DETERMINING HOW WARM
TEMPS GO OVER THE SOUTHEASTERN PORTIONS OF THE FORECAST AREA. WITH
WARM ADVECTION TODAY...LOW LEVEL THERMALS SUPPORTIVE OF MAX TEMPS IN
THE LOWER/MIDDLE 50S. GENERALLY NEAR MAVMOS GUIDANCE...ALTHOUGH DID
UNDERCUT MAV BY A FEW DEGREES OVER SOUTHERN COUNTIES WITH POTENTIAL
IMPACTS FROM CLOUDS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 336 AM EDT TUE MAR 18 2014
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TONIGHT/WEDNESDAY AND
AGAIN THURSDAY NIGHT WITH TWO SYSTEMS IMPACTING THE REGION.
LOW PRESSURE WILL PINWHEEL INTO THE GREAT LAKES WEDNESDAY AND SWING
A COLD FRONT ACROSS CENTRAL INDIANA DURING THE MORNING. MOISTURE
FETCH IS LIMITED OVERALL BUT FORCING THROUGH THE BOUNDARY LAYER AND
DIFFLUENCE ALOFT SHOULD BE MORE THAN SUFFICIENT FOR PRECIP TO
DEVELOP LATE TONIGHT INTO WEDNESDAY MORNING. STRENGTHENING LOW LEVEL
JET WILL ROTATE ACROSS CENTRAL INDIANA LATE TONIGHT AND PROMOTE A
BRIEF PERIOD WITH ISENTROPIC LIFT AHEAD OF THE FRONT AS WELL. WILL
CARRY LIKELY POPS OVER NORTHERN COUNTIES LATE TONIGHT AND WEDNESDAY
MORNING IN CLOSEST PROXIMITY TO BETTER FORCING AND DEEPER MOISTURE
WITH CHANCE POPS FURTHER SOUTH ACROSS THE FORECAST AREA. POTENTIAL
EXISTS FOR A CONVECTIVE COMPONENT TO PRECIP AND POTENTIALLY A FEW
RUMBLES OF THUNDER OVER THE NORTHERN WABASH VALLEY AS SOME ELEVATED
INSTABILITY WILL BE PRESENT.
BIG ISSUE WITH THE PASSAGE OF THE COLD FRONT WILL BE THE WINDS. THE
LOW LEVEL JET MOVING ACROSS THE REGION LATE TONIGHT WILL PROMOTE
GUSTS INCREASING TO 20-30MPH...BUT PRESENCE OF A BOUNDARY LAYER
INVERSION SHOULD LIMIT WHAT MAKES IT TO THE GROUND. AS COLD
ADVECTION TAKES HOLD ONCE THE FRONT GOES BY WEDNESDAY MORNING
HOWEVER...MODEL SOUNDINGS SHOW AN ENVIRONMENT CONDUCIVE FOR STRONGER
WINDS ALOFT BEING PULLED TO THE SURFACE AS STEEPENING LAPSE RATES
PROMOTE EXCELLENT LOW LEVEL MIXING. MAX GUSTS OF 35-40 MPH LIKELY
DURING THE AFTERNOON...AND MAY APPROACH WIND ADVISORY CRITERIA AS
WELL. WILL MAINTAIN LOW CHANCE POPS THROUGH THE AFTERNOON WITH
SUBTLE INSTABILITY PRESENT.
ANY PRECIP CHANCES WILL END BY WEDNESDAY NIGHT AS THE LOW LIFTS OUT
TO THE NORTHEAST AND IS REPLACED BY A SURFACE RIDGE. EXPECT DRY
CONDITIONS TO PERSIST INTO THURSDAY EVENING AS THE RIDGE PASSES
THROUGH THE OHIO VALLEY. A WARM FRONT WILL MOVE INTO THE REGION
THURSDAY NIGHT AIDED BY A 30-40KT LOW LEVEL JET. NICE AXIS OF LOW
LEVEL CONVERGENCE AND ISENTROPIC LIFT DEVELOPING AT THE NOSE OF THE
JET ACROSS THE NORTHERN HALF OF THE FORECAST AREA WILL SUPPORT SOME
RAIN SHOWER DEVELOPMENT ALONG THE WARM FRONT. MOST OF THE PRECIP
SHOULD MOVE NORTH OF THE FORECAST AREA WITH THE BOUNDARY BY 12Z
FRIDAY.
TEMPS...HIGHS EXPECTED BY MIDDAY WEDNESDAY WITH SLOWLY FALLING TEMPS
THEREAFTER WITHIN THE COLD ADVECTION. PREFERRED COLDER MAVMOS HIGHS.
MAVMOS WAS ALSO PREFERRED FOR THURSDAY AS TEMPS EXPECTED TO RECOVER
NICELY INTO THE 50S WITH WARM ADVECTION DEVELOPING IN ADVANCE OF THE
WARM FRONT LATE DAY. MOS GUIDANCE APPEARED REASONABLE FOR LOWS
THROUGHOUT THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
ISSUED AT 310 AM EDT TUE MAR 18 2014
MODELS CONTINUE TO SUGGEST A PROGRESSIVE PATTERN DURING THE LONG
TERM PORTION OF THE FORECAST...WITH A LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT FRIDAY INTO FRIDAY NIGHT...AND ANOTHER ONE
EARLY NEXT WEEK.
FIRST SYSTEM FRIDAY INTO FRIDAY NIGHT MAY BRING A FEW
THUNDERSTORMS AS K INDICES AS HIGH AS 30 PLUS INDICATE A HEALTHY
PREFRONTAL INSTABILITY AXIS FRIDAY EVENING. EARLY NEXT WEEK SYSTEM
IS MUCH MORE BORDERLINE TEMPERATURE WISE...AND WILL CARRY RAIN OR
SNOW FOR NOW.
TEMPERATURES WILL BEGIN QUITE WARM IN THE STRONG WARM ADVECTION
AHEAD OF THE FRONT...BEFORE BECOMING NEAR TO BELOW NORMAL OVER THE
WEEKEND. NEAR TO JUST BEYOND THE SEVEN DAY FORECAST
PERIOD...GUIDANCE SUGGESTS POTENTIAL FOR YET ANOTHER COLD
INTRUSION FROM THE WINTER THAT REFUSES TO END.
&&
.AVIATION /DISCUSSION FOR THE 18/15Z KIND TAF UPDATE/...
ISSUED AT 1030 AM EDT TUE MAR 18 2014
.UPDATE...SATELLITE AND QUICK LOOK OUT THE WIND INDICATES STRATUS
DECK IS JUST ABOUT TO REACH KIND. THE LAYER APPEARS RATHER THIN
AND WILL MENTION SCT-BKN AROUND 2 THOUSAND FEET NEXT FEW HOURS.
NO OTHER CHANGES NEEDED AT THIS TIME. PREVIOUS AVIATION DISCUSSION
FOLLOWS...
MVFR CONDITIONS WILL LIKELY BEGIN QUICKLY AT BMG AND WITHIN THE
FIRST FEW HOURS AT IND/HUF AS A STRATUS DECK EXPANDS NORTHWESTWARD.
LAF MAY ESCAPE MVFR CONDITIONS AS MIXING BEGINS TO ERODE THE STRATUS
DECK LATER THIS MORNING.
HAVE ATTEMPTED TO TIME THE STRATUS DECK INTO IND/HUF. SREF
PROBABILITIES DO NOT FULLY CAPTURE ITS EXTENT...BUT DO DEPICT IT
MIXING OUT LATER TODAY. HAVE HELD ONTO IT INTO THE EARLY AFTERNOON
HOURS AS THIS WAS THE CASE YESTERDAY AND IT WILL TAKE AT LEAST A FEW
HOURS OF GOOD MIXING TO ERODE IT EFFECTIVELY.
WINDS WILL GUST TO AROUND THE 20KT LEVEL AT ALL SITES THIS
AFTERNOON...OUT OF THE SOUTHEAST. GUSTS WILL CALM DOWN THIS
EVENING...WITH WINDS BECOMING SOUTHERLY OVERNIGHT.
MVFR CONDITIONS MAY REDEVELOP LATE TONIGHT AS THE NEXT SYSTEM
APPROACHES AND SHOWERS MOVE INTO THE AREA. HAVE CARRIED VCSH FOR NOW
AND WILL ALLOW FUTURE PACKAGES TO REFINE TIMING.
OUTSIDE OF ANY POSSIBLE SHOWERS...DO NOT EXPECT SIGNIFICANT
VISIBILITY ISSUES DURING THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN/JAS
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...NIELD/JH
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1008 AM EDT TUE MAR 18 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 AM EDT TUE MAR 18 2014
AFTER A DRY MILD DAY TODAY...RAIN SHOWERS WILL DEVELOP LATE TONIGHT
INTO WEDNESDAY AS A COLD FRONT MOVES THROUGH. COOLER DRIER WEATHER
IS EXPECTED FOR WEDNESDAY NIGHT AND THURSDAY. TEMPERATURES WILL ONCE
AGAIN TURN WARMER FOR FRIDAY WITH THE PASSAGE OF A WARM FRONT. RAIN
AND EMBEDDED THUNDERSTORMS WILL ACCOMPANY THE PASSAGE OF LOW
PRESSURE FRIDAY NIGHT. HIGH PRESSURE THEN REESTABLISHES FOR THE
WEEKEND WITH DRY AND PROGRESSIVELY COLDER AIR.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1008 AM EDT TUE MAR 18 2014
AREA OF LOW CLOUDS OVER SOUTHERN INDIANA HAS BEEN EXPANDING
NORTHWEST DURING THE PAST FEW HOURS. PILOT REPORTS INDICATE THIS
CLOUD DECK IS QUITE THIN...SO EXPECTING THESE CLOUDS TO SCATTER OUT
THIS AFTERNOON. THINK PARTLY CLOUDY WILL STILL WORK OVERALL
TODAY...BUT THERE WILL PROBABLY BE A PERIOD OF MAINLY CLOUDY SKIES
THROUGH EARLY AFTERNOON...ESPECIALLY OVER THE SOUTHERN THROUGH WEST
CENTRAL ZONES.
THIS MORNING/S UPPER AIR SUGGEST TODAY/S HIGHS ARE WITHIN
REACH...BUT THEY WILL DEPEND ON HOW FAST LOW CLOUDS DISSIPATE. WILL
NOT MAKE ANY CHANGES AT THIS TIME...BUT THE HIGHS MAY NEED TO BE
LOWERED LATER TODAY WHEN LOW CLOUD TRENDS BECOME MORE APPARENT.
PREVIOUS DISCUSSION FOLLOWS.
HIGH CLOUDS DRIFTING THROUGH EARLY THIS MORNING WITH WEAK HIGH
PRESSURE ACROSS THE OHIO VALLEY. LARGE AREA OF STRATUS MOVING W/NW
ACROSS KENTUCKY AS WELL. WITH LIGHT E/SE FLOW...TEMPS RANGED FROM
THE MID 20S TO LOWER 30S ACROSS THE FORECAST AREA AT 07Z.
INITIAL ISSUE FOCUSES ON THE STRATUS DECK EXPANDING TOWARDS THE
FORECAST AREA FROM THE SOUTHEAST. SHORT RANGE MODEL GUIDANCE
ADVECTING DEEPER MOISTURE INTO THE REGION THROUGH THE MORNING AS
LOW LEVEL FLOW VEERS TO A S/SE DIRECTION. AT THE SAME TIME...BOTH
THE RAP AND NAM APPEAR TO BE OVERDOING MOISTURE ON THE 925/950 MB
LEVELS VERSUS THE LEADING EDGE OF THE CURRENT STRATUS DECK AS OF
07Z. CONFIDENCE IS GROWING IN LOWER CLOUDS REACHING THE SOUTHEASTERN
PORTIONS OF THE FORECAST AREA OVER THE NEXT FEW HOURS...AND POSSIBLY
GETTING AS FAR NORTH AS I-70 OVER THE EASTERN HALF OF CENTRAL
INDIANA AFTER DAYBREAK. WILL INCREASE CLOUD COVERAGE GRIDS SOUTHEAST
OF THE INDY METRO FOR THE MORNING AND MONITOR FOR ANY ADDITIONAL
UPDATES OVER THE NEXT FEW HOURS.
ELSEWHERE ACROSS CENTRAL INDIANA...MID AND HIGH LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN ADVANCE OF LOW PRESSURE
TRACKING THROUGH THE CENTRAL PLAINS. EXPECT AN INCREASE IN SURFACE
WINDS BY THIS AFTERNOON AS THE LOW APPROACHES...WITH SUSTAINEDS TO
NEAR 15MPH BY LATE DAY.
TEMPS...EVENTUAL EXTENT OF STRATUS DECK BOTH IN COVERAGE AND TIME
WILL BE CRITICAL...AS THEY WERE ON MONDAY...ON DETERMINING HOW WARM
TEMPS GO OVER THE SOUTHEASTERN PORTIONS OF THE FORECAST AREA. WITH
WARM ADVECTION TODAY...LOW LEVEL THERMALS SUPPORTIVE OF MAX TEMPS IN
THE LOWER/MIDDLE 50S. GENERALLY NEAR MAVMOS GUIDANCE...ALTHOUGH DID
UNDERCUT MAV BY A FEW DEGREES OVER SOUTHERN COUNTIES WITH POTENTIAL
IMPACTS FROM CLOUDS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 336 AM EDT TUE MAR 18 2014
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TONIGHT/WEDNESDAY AND
AGAIN THURSDAY NIGHT WITH TWO SYSTEMS IMPACTING THE REGION.
LOW PRESSURE WILL PINWHEEL INTO THE GREAT LAKES WEDNESDAY AND SWING
A COLD FRONT ACROSS CENTRAL INDIANA DURING THE MORNING. MOISTURE
FETCH IS LIMITED OVERALL BUT FORCING THROUGH THE BOUNDARY LAYER AND
DIFFLUENCE ALOFT SHOULD BE MORE THAN SUFFICIENT FOR PRECIP TO
DEVELOP LATE TONIGHT INTO WEDNESDAY MORNING. STRENGTHENING LOW LEVEL
JET WILL ROTATE ACROSS CENTRAL INDIANA LATE TONIGHT AND PROMOTE A
BRIEF PERIOD WITH ISENTROPIC LIFT AHEAD OF THE FRONT AS WELL. WILL
CARRY LIKELY POPS OVER NORTHERN COUNTIES LATE TONIGHT AND WEDNESDAY
MORNING IN CLOSEST PROXIMITY TO BETTER FORCING AND DEEPER MOISTURE
WITH CHANCE POPS FURTHER SOUTH ACROSS THE FORECAST AREA. POTENTIAL
EXISTS FOR A CONVECTIVE COMPONENT TO PRECIP AND POTENTIALLY A FEW
RUMBLES OF THUNDER OVER THE NORTHERN WABASH VALLEY AS SOME ELEVATED
INSTABILITY WILL BE PRESENT.
BIG ISSUE WITH THE PASSAGE OF THE COLD FRONT WILL BE THE WINDS. THE
LOW LEVEL JET MOVING ACROSS THE REGION LATE TONIGHT WILL PROMOTE
GUSTS INCREASING TO 20-30MPH...BUT PRESENCE OF A BOUNDARY LAYER
INVERSION SHOULD LIMIT WHAT MAKES IT TO THE GROUND. AS COLD
ADVECTION TAKES HOLD ONCE THE FRONT GOES BY WEDNESDAY MORNING
HOWEVER...MODEL SOUNDINGS SHOW AN ENVIRONMENT CONDUCIVE FOR STRONGER
WINDS ALOFT BEING PULLED TO THE SURFACE AS STEEPENING LAPSE RATES
PROMOTE EXCELLENT LOW LEVEL MIXING. MAX GUSTS OF 35-40 MPH LIKELY
DURING THE AFTERNOON...AND MAY APPROACH WIND ADVISORY CRITERIA AS
WELL. WILL MAINTAIN LOW CHANCE POPS THROUGH THE AFTERNOON WITH
SUBTLE INSTABILITY PRESENT.
ANY PRECIP CHANCES WILL END BY WEDNESDAY NIGHT AS THE LOW LIFTS OUT
TO THE NORTHEAST AND IS REPLACED BY A SURFACE RIDGE. EXPECT DRY
CONDITIONS TO PERSIST INTO THURSDAY EVENING AS THE RIDGE PASSES
THROUGH THE OHIO VALLEY. A WARM FRONT WILL MOVE INTO THE REGION
THURSDAY NIGHT AIDED BY A 30-40KT LOW LEVEL JET. NICE AXIS OF LOW
LEVEL CONVERGENCE AND ISENTROPIC LIFT DEVELOPING AT THE NOSE OF THE
JET ACROSS THE NORTHERN HALF OF THE FORECAST AREA WILL SUPPORT SOME
RAIN SHOWER DEVELOPMENT ALONG THE WARM FRONT. MOST OF THE PRECIP
SHOULD MOVE NORTH OF THE FORECAST AREA WITH THE BOUNDARY BY 12Z
FRIDAY.
TEMPS...HIGHS EXPECTED BY MIDDAY WEDNESDAY WITH SLOWLY FALLING TEMPS
THEREAFTER WITHIN THE COLD ADVECTION. PREFERRED COLDER MAVMOS HIGHS.
MAVMOS WAS ALSO PREFERRED FOR THURSDAY AS TEMPS EXPECTED TO RECOVER
NICELY INTO THE 50S WITH WARM ADVECTION DEVELOPING IN ADVANCE OF THE
WARM FRONT LATE DAY. MOS GUIDANCE APPEARED REASONABLE FOR LOWS
THROUGHOUT THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
ISSUED AT 310 AM EDT TUE MAR 18 2014
MODELS CONTINUE TO SUGGEST A PROGRESSIVE PATTERN DURING THE LONG
TERM PORTION OF THE FORECAST...WITH A LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT FRIDAY INTO FRIDAY NIGHT...AND ANOTHER ONE
EARLY NEXT WEEK.
FIRST SYSTEM FRIDAY INTO FRIDAY NIGHT MAY BRING A FEW
THUNDERSTORMS AS K INDICES AS HIGH AS 30 PLUS INDICATE A HEALTHY
PREFRONTAL INSTABILITY AXIS FRIDAY EVENING. EARLY NEXT WEEK SYSTEM
IS MUCH MORE BORDERLINE TEMPERATURE WISE...AND WILL CARRY RAIN OR
SNOW FOR NOW.
TEMPERATURES WILL BEGIN QUITE WARM IN THE STRONG WARM ADVECTION
AHEAD OF THE FRONT...BEFORE BECOMING NEAR TO BELOW NORMAL OVER THE
WEEKEND. NEAR TO JUST BEYOND THE SEVEN DAY FORECAST
PERIOD...GUIDANCE SUGGESTS POTENTIAL FOR YET ANOTHER COLD
INTRUSION FROM THE WINTER THAT REFUSES TO END.
&&
.AVIATION /DISCUSSION FOR THE 18/12Z TAFS/...
ISSUED AT 717 AM EDT TUE MAR 18 2014
MVFR CONDITIONS WILL LIKELY BEGIN QUICKLY AT BMG AND WITHIN THE
FIRST FEW HOURS AT IND/HUF AS A STRATUS DECK EXPANDS NORTHWESTWARD.
LAF MAY ESCAPE MVFR CONDITIONS AS MIXING BEGINS TO ERODE THE STRATUS
DECK LATER THIS MORNING.
HAVE ATTEMPTED TO TIME THE STRATUS DECK INTO IND/HUF. SREF
PROBABILITIES DO NOT FULLY CAPTURE ITS EXTENT...BUT DO DEPICT IT
MIXING OUT LATER TODAY. HAVE HELD ONTO IT INTO THE EARLY AFTERNOON
HOURS AS THIS WAS THE CASE YESTERDAY AND IT WILL TAKE AT LEAST A FEW
HOURS OF GOOD MIXING TO ERODE IT EFFECTIVELY.
WINDS WILL GUST TO AROUND THE 20KT LEVEL AT ALL SITES THIS
AFTERNOON...OUT OF THE SOUTHEAST. GUSTS WILL CALM DOWN THIS
EVENING...WITH WINDS BECOMING SOUTHERLY OVERNIGHT.
MVFR CONDITIONS MAY REDEVELOP LATE TONIGHT AS THE NEXT SYSTEM
APPROACHES AND SHOWERS MOVE INTO THE AREA. HAVE CARRIED VCSH FOR NOW
AND WILL ALLOW FUTURE PACKAGES TO REFINE TIMING.
OUTSIDE OF ANY POSSIBLE SHOWERS...DO NOT EXPECT SIGNIFICANT
VISIBILITY ISSUES DURING THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN/JAS
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...NIELD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
717 AM EDT TUE MAR 18 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 AM EDT TUE MAR 18 2014
AFTER A DRY MILD DAY TODAY...RAIN SHOWERS WILL DEVELOP LATE TONIGHT
INTO WEDNESDAY AS A COLD FRONT MOVES THROUGH. COOLER DRIER WEATHER
IS EXPECTED FOR WEDNESDAY NIGHT AND THURSDAY. TEMPERATURES WILL ONCE
AGAIN TURN WARMER FOR FRIDAY WITH THE PASSAGE OF A WARM FRONT. RAIN
AND EMBEDDED THUNDERSTORMS WILL ACCOMPANY THE PASSAGE OF LOW
PRESSURE FRIDAY NIGHT. HIGH PRESSURE THEN REESTABLISHES FOR THE
WEEKEND WITH DRY AND PROGRESSIVELY COLDER AIR.
&&
.NEAR TERM /TODAY/...
ISSUED AT 336 AM EDT TUE MAR 18 2014
HIGH CLOUDS DRIFTING THROUGH EARLY THIS MORNING WITH WEAK HIGH
PRESSURE ACROSS THE OHIO VALLEY. LARGE AREA OF STRATUS MOVING W/NW
ACROSS KENTUCKY AS WELL. WITH LIGHT E/SE FLOW...TEMPS RANGED FROM
THE MID 20S TO LOWER 30S ACROSS THE FORECAST AREA AT 07Z.
INITIAL ISSUE FOCUSES ON THE STRATUS DECK EXPANDING TOWARDS THE
FORECAST AREA FROM THE SOUTHEAST. SHORT RANGE MODEL GUIDANCE
ADVECTING DEEPER MOISTURE INTO THE REGION THROUGH THE MORNING AS
LOW LEVEL FLOW VEERS TO A S/SE DIRECTION. AT THE SAME TIME...BOTH
THE RAP AND NAM APPEAR TO BE OVERDOING MOISTURE ON THE 925/950 MB
LEVELS VERSUS THE LEADING EDGE OF THE CURRENT STRATUS DECK AS OF
07Z. CONFIDENCE IS GROWING IN LOWER CLOUDS REACHING THE SOUTHEASTERN
PORTIONS OF THE FORECAST AREA OVER THE NEXT FEW HOURS...AND POSSIBLY
GETTING AS FAR NORTH AS I-70 OVER THE EASTERN HALF OF CENTRAL
INDIANA AFTER DAYBREAK. WILL INCREASE CLOUD COVERAGE GRIDS SOUTHEAST
OF THE INDY METRO FOR THE MORNING AND MONITOR FOR ANY ADDITIONAL
UPDATES OVER THE NEXT FEW HOURS.
ELSEWHERE ACROSS CENTRAL INDIANA...MID AND HIGH LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN ADVANCE OF LOW PRESSURE
TRACKING THROUGH THE CENTRAL PLAINS. EXPECT AN INCREASE IN SURFACE
WINDS BY THIS AFTERNOON AS THE LOW APPROACHES...WITH SUSTAINEDS TO
NEAR 15MPH BY LATE DAY.
TEMPS...EVENTUAL EXTENT OF STRATUS DECK BOTH IN COVERAGE AND TIME
WILL BE CRITICAL...AS THEY WERE ON MONDAY...ON DETERMINING HOW WARM
TEMPS GO OVER THE SOUTHEASTERN PORTIONS OF THE FORECAST AREA. WITH
WARM ADVECTION TODAY...LOW LEVEL THERMALS SUPPORTIVE OF MAX TEMPS IN
THE LOWER/MIDDLE 50S. GENERALLY NEAR MAVMOS GUIDANCE...ALTHOUGH DID
UNDERCUT MAV BY A FEW DEGREES OVER SOUTHERN COUNTIES WITH POTENTIAL
IMPACTS FROM CLOUDS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 336 AM EDT TUE MAR 18 2014
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TONIGHT/WEDNESDAY AND
AGAIN THURSDAY NIGHT WITH TWO SYSTEMS IMPACTING THE REGION.
LOW PRESSURE WILL PINWHEEL INTO THE GREAT LAKES WEDNESDAY AND SWING
A COLD FRONT ACROSS CENTRAL INDIANA DURING THE MORNING. MOISTURE
FETCH IS LIMITED OVERALL BUT FORCING THROUGH THE BOUNDARY LAYER AND
DIFFLUENCE ALOFT SHOULD BE MORE THAN SUFFICIENT FOR PRECIP TO
DEVELOP LATE TONIGHT INTO WEDNESDAY MORNING. STRENGTHENING LOW LEVEL
JET WILL ROTATE ACROSS CENTRAL INDIANA LATE TONIGHT AND PROMOTE A
BRIEF PERIOD WITH ISENTROPIC LIFT AHEAD OF THE FRONT AS WELL. WILL
CARRY LIKELY POPS OVER NORTHERN COUNTIES LATE TONIGHT AND WEDNESDAY
MORNING IN CLOSEST PROXIMITY TO BETTER FORCING AND DEEPER MOISTURE
WITH CHANCE POPS FURTHER SOUTH ACROSS THE FORECAST AREA. POTENTIAL
EXISTS FOR A CONVECTIVE COMPONENT TO PRECIP AND POTENTIALLY A FEW
RUMBLES OF THUNDER OVER THE NORTHERN WABASH VALLEY AS SOME ELEVATED
INSTABILITY WILL BE PRESENT.
BIG ISSUE WITH THE PASSAGE OF THE COLD FRONT WILL BE THE WINDS. THE
LOW LEVEL JET MOVING ACROSS THE REGION LATE TONIGHT WILL PROMOTE
GUSTS INCREASING TO 20-30MPH...BUT PRESENCE OF A BOUNDARY LAYER
INVERSION SHOULD LIMIT WHAT MAKES IT TO THE GROUND. AS COLD
ADVECTION TAKES HOLD ONCE THE FRONT GOES BY WEDNESDAY MORNING
HOWEVER...MODEL SOUNDINGS SHOW AN ENVIRONMENT CONDUCIVE FOR STRONGER
WINDS ALOFT BEING PULLED TO THE SURFACE AS STEEPENING LAPSE RATES
PROMOTE EXCELLENT LOW LEVEL MIXING. MAX GUSTS OF 35-40 MPH LIKELY
DURING THE AFTERNOON...AND MAY APPROACH WIND ADVISORY CRITERIA AS
WELL. WILL MAINTAIN LOW CHANCE POPS THROUGH THE AFTERNOON WITH
SUBTLE INSTABILITY PRESENT.
ANY PRECIP CHANCES WILL END BY WEDNESDAY NIGHT AS THE LOW LIFTS OUT
TO THE NORTHEAST AND IS REPLACED BY A SURFACE RIDGE. EXPECT DRY
CONDITIONS TO PERSIST INTO THURSDAY EVENING AS THE RIDGE PASSES
THROUGH THE OHIO VALLEY. A WARM FRONT WILL MOVE INTO THE REGION
THURSDAY NIGHT AIDED BY A 30-40KT LOW LEVEL JET. NICE AXIS OF LOW
LEVEL CONVERGENCE AND ISENTROPIC LIFT DEVELOPING AT THE NOSE OF THE
JET ACROSS THE NORTHERN HALF OF THE FORECAST AREA WILL SUPPORT SOME
RAIN SHOWER DEVELOPMENT ALONG THE WARM FRONT. MOST OF THE PRECIP
SHOULD MOVE NORTH OF THE FORECAST AREA WITH THE BOUNDARY BY 12Z
FRIDAY.
TEMPS...HIGHS EXPECTED BY MIDDAY WEDNESDAY WITH SLOWLY FALLING TEMPS
THEREAFTER WITHIN THE COLD ADVECTION. PREFERRED COLDER MAVMOS HIGHS.
MAVMOS WAS ALSO PREFERRED FOR THURSDAY AS TEMPS EXPECTED TO RECOVER
NICELY INTO THE 50S WITH WARM ADVECTION DEVELOPING IN ADVANCE OF THE
WARM FRONT LATE DAY. MOS GUIDANCE APPEARED REASONABLE FOR LOWS
THROUGHOUT THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
ISSUED AT 310 AM EDT TUE MAR 18 2014
MODELS CONTINUE TO SUGGEST A PROGRESSIVE PATTERN DURING THE LONG
TERM PORTION OF THE FORECAST...WITH A LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT FRIDAY INTO FRIDAY NIGHT...AND ANOTHER ONE
EARLY NEXT WEEK.
FIRST SYSTEM FRIDAY INTO FRIDAY NIGHT MAY BRING A FEW
THUNDERSTORMS AS K INDICES AS HIGH AS 30 PLUS INDICATE A HEALTHY
PREFRONTAL INSTABILITY AXIS FRIDAY EVENING. EARLY NEXT WEEK SYSTEM
IS MUCH MORE BORDERLINE TEMPERATURE WISE...AND WILL CARRY RAIN OR
SNOW FOR NOW.
TEMPERATURES WILL BEGIN QUITE WARM IN THE STRONG WARM ADVECTION
AHEAD OF THE FRONT...BEFORE BECOMING NEAR TO BELOW NORMAL OVER THE
WEEKEND. NEAR TO JUST BEYOND THE SEVEN DAY FORECAST
PERIOD...GUIDANCE SUGGESTS POTENTIAL FOR YET ANOTHER COLD
INTRUSION FROM THE WINTER THAT REFUSES TO END.
&&
.AVIATION /DISCUSSION FOR THE 18/12Z TAFS/...
ISSUED AT 717 AM EDT TUE MAR 18 2014
MVFR CONDITIONS WILL LIKELY BEGIN QUICKLY AT BMG AND WITHIN THE
FIRST FEW HOURS AT IND/HUF AS A STRATUS DECK EXPANDS NORTHWESTWARD.
LAF MAY ESCAPE MVFR CONDITIONS AS MIXING BEGINS TO ERODE THE STRATUS
DECK LATER THIS MORNING.
HAVE ATTEMPTED TO TIME THE STRATUS DECK INTO IND/HUF. SREF
PROBABILITIES DO NOT FULLY CAPTURE ITS EXTENT...BUT DO DEPICT IT
MIXING OUT LATER TODAY. HAVE HELD ONTO IT INTO THE EARLY AFTERNOON
HOURS AS THIS WAS THE CASE YESTERDAY AND IT WILL TAKE AT LEAST A FEW
HOURS OF GOOD MIXING TO ERODE IT EFFECTIVELY.
WINDS WILL GUST TO AROUND THE 20KT LEVEL AT ALL SITES THIS
AFTERNOON...OUT OF THE SOUTHEAST. GUSTS WILL CALM DOWN THIS
EVENING...WITH WINDS BECOMING SOUTHERLY OVERNIGHT.
MVFR CONDITIONS MAY REDEVELOP LATE TONIGHT AS THE NEXT SYSTEM
APPROACHES AND SHOWERS MOVE INTO THE AREA. HAVE CARRIED VCSH FOR NOW
AND WILL ALLOW FUTURE PACKAGES TO REFINE TIMING.
OUTSIDE OF ANY POSSIBLE SHOWERS...DO NOT EXPECT SIGNIFICANT
VISIBILITY ISSUES DURING THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...NIELD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
734 AM EDT TUE MAR 18 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 434 AM EDT TUE MAR 18 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WNW FLOW ALF OVER
THE UPR LKS BTWN PERSISTENT MEAN TROF OVER QUEBEC AND RDG ALONG THE
W COAST. A VIGOROUS SHRTWV THAT TOPPED THE WRN RDG IS MOVING ESEWD
THRU THE CENTRAL ROCKIES...ACCOMPANIED BY 12Z-24Z H3 HGT FALLS UP TO
300M IN WYOMING. THERE HAVE EVEN BEEN A FEW LTG STRIKES IN THE COMMA
HEAD OF THE ACCOMPANYING CLD SHIELD OVER THE NRN ROCKIES INTO THE
NRN PLAINS. BAND OF ENHANCED CLD TO THE NE OF DVLPG SFC LO PRES IN
NEBRASKA EXTENDS NE INTO CNTRL MN/NW WI...CORRELATED BEST WITH AXIS
OF HIER H7-6 FGEN...BUT WELL N OF H85 WARM FNT STRETCHING FM SDAKOTA
THRU NRN IOWA. PCPN HAS HAD A HARD TIME DEVELOPING UNDER THE SHARPER
FGEN DUE TO RATHER DRY NATURE OF THE 00Z MPX RAOB...BUT SOME SN HAS
REACHED AS FAR NE AS HYR IN NW WI AS OF 09Z. ALTHOUGH SKIES ARE CLDY
OVER UPR MI...THERE IS CURRENTLY NO PCPN FALLING OVER THE CWA
DESPITE LARGER SCALE WAD AND PRESENCE OF WEAKER H85 WARM FNT
ASSOCIATED WITH SHRTWV TRACKING ACRS NRN LK SUP IN WNW FLOW ALF.
FEED OF LLVL DRY AIR SHOWN ON THE 00Z GRB RAOB IS LIKELY PLAYING A
ROLE. EVEN DEEPER DRIER AIR IS PRESENT S OF GRB.
MAIN FCST CONCERNS THRU TNGT WL FOCUS ON POPS/SN AMOUNTS AND NEED
FOR HEADLINES AS SHRTWV/ACCOMPANYING SFC LO OVER THE ROCKIES/PLAINS
MOVE TO THE E.
TODAY...AS S WINDS TO THE E OF DEEPENING LO PRES IN THE PLAINS
STRENGTHEN...BAND OF SHARPER H7-6 FGEN IS FCST TO SHIFT TO THE NE
INTO UPR MI. MORE DYNAMIC SUPPORT WL COME FM UPR DVGC IN RRQ OF H3
JET MAX FCST TO BE MOVING NEWD THRU ONTARIO. SINCE NEGATIVE H85
DEWPT ADVECTION ASSOCIATED WITH THE DRY AIR TO THE S WL BE IMPACTING
MAINLY THE E HALF OF THE CWA...ACCOMPANYING POPS WL BE HIER OVER THE
W. BUT EVEN THERE...MOST OF THE MODELS SHOW SOME DRYING WL ARRIVE
AND SHUNT THE PCPN OFF INTO NW LK SUP AS AXIS OF FGEN SHIFTS TO THE
NW AS WELL. THE NAM IS MOST AGGRESSIVE WITH THIS DRYING. AS FAR AS
SN AMOUNTS ARE CONCERNED...AXIS OF H7 SPECIFIC HUMIDITY UP TO 3 G/KG
IS FCST TO BE OVER THE AXIS OF SHARPER FGEN THIS MRNG. BUT INFLUX OF
DRIER LLVL AIR IS FCST TO DIMINISH THIS VALUE THRU THE DAY.
OVERALL...SUSPECT SN AMOUNTS WL APRCH ADVY CRITERIA OVER THE FAR W
WHERE THE FGEN IS PROGGED TO BE MOST PERSISTENT AND DRYING LESS
AGGRESSIVE. NARROW...RATHER HI...NARROW DGZ RESULTING IN SN/WATER
RATIOS IN THE 10-15:1 RANGE WL NOT HELP SN TOTALS.
TNGT...SHRTWV FM THE PLAINS IS FCST TO BECOME MORE NEGATIVELY TILTED
AS IT MOVES INTO WI BY 12Z WED. ALTHOUGH DEEP LYR QVECTOR CNVGC IN
THE DVPA/PERSISTENT ISENTROPIC ASCENT AHEAD OF THIS FEATURE IS FCST
TO OVERSPREAD THE CWA...THE SHARPER FORCING AND ACCOMPANYING H4-2
DVGC ARE PROGGED TO IMPACT THE SE HALF OF THE CWA...WHERE THE DRIER
AIR IS FCST TO BE DEEPEST. OUT OF SYNC NATURE OF THE FORCING/DEEPER
MSTR IS OF CONCERN AND WL LIKELY LIMIT SN TOTALS. IN FACT...MODEL
QPF VARIES SGNFTLY ACRS THE CWA. ADVY SN IS MOST LIKELY OVER THE W
HALF WHERE MSTR IS DEEPER AND SHARPENING CYC NNE FLOW LATER TNGT
MIGHT ENHANCE SN TOTALS A BIT. SINCE THERE IS LTL INTERACTION WITH
THE ARCTIC BRANCH IN CANADA...ANOTHER FACTOR THAT WL LIMIT
QPF...MODELS HAVE TRENDED A BIT FARTHER S WITH THE SFC LO TRACK...
INDICATING THE SFC LO WL REACH NO FARTHER N THAN ABOUT MILWAUKEE BY
12Z WED. THESE TRENDS SUG THE BULK OF THE PCPN WL BE IN THE FORM OF
SN. RETAINED A MENTION OF -FZRA OVER THE SE PER THE WARMER NAM
MODEL...WHICH SHOWS ELEVATED WARM LYR CENTERED AT 3K FT THRU THE NGT
NEAR LK MI. LATER SHIFTS MAY BE ABLE TO REMOVE THIS MENTION OF MIXED
PCPN IF CURRENT TRENDS PERSIST.
AS FOR HEADLINES...OPTED TO ISSUE AN ADVY FOR THE W TODAY GIVEN AXIS
OF SHARPER FGEN/LATER DRYING. EXPANDED THE ADVYS TO THE E TO COVER
THE ENTIRE CWA BY LATE TNGT TO REFLECT ARRIVAL OF SHARPER DYNAMICS/
HIER POPS THAT WL INFLUENCE THE AREA INTO WED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 524 AM EDT TUE MAR 18 2014
STRONG SOUTHERN STREAM SYSTEM CROSSES THE GREAT LAKES TO START THE
DAY ON WEDNESDAY. MODELS ARE SETTLING ON A SFC LOW AROUND DAYBREAK
ON WEDNESDAY NEAR MILWAUKEE WI...TRACKING INTO THE NORTHERN PART OF
LK HURON BY WEDNESDAY EVENING. UPPER LEVELS BECOME NEGATIVE TILTED
LATE TONIGHT INTO WEDNESDAY...BUT WITHOUT MUCH ADDITIONAL INTERACTION
FROM NORTHERN BRANCH SHORTWAVES/COLD AIR...SYSTEM IS LOOKING MORE
PROGRESSIVE THAN IT DID 24 HR AGO. THIS SHOWS UP SEEING THE FARTHER
SOUTH AND EAST SFC LOW /GEM-NH HAS SHOWN THIS FOR MULTIPLE RUNS/.
WARM LAYER NOT VERY MUCH OF A FACTOR NOW EITHER...PERHAPS REACHING
INTO FAR SE CWA FOR A VERY BRIEF TIME LATE TONIGHT THROUGH AROUND
DAYBREAK ON WEDNESDAY. PROGRESSIVE NATURE OF SYSTEM IS VERY APPARENT
BY LOOKING AT H85-H7 MOISTURE TRANSPORT...WHICH IS NOW MAXIMIZING
LATE TONIGHT INTO WEDNESDAY OVER THE CNTRL GREAT LAKES INSTEAD OF
INTO CNTRL UPR MICHIGAN. THUS...NOT AS MUCH MOISTURE FOR THE SYSTEM
TO WORK WITH AND H7 MIXING RATIOS ONLY TOP OUT BTWN 2.25 AND 2.5G/KG
COMPARED TO THE 3.0 OR HIGHER VALUES SHOWN PREVIOUSLY. USING THE
GARCIA METHOD THIS WOULD SUGGEST UP TO 5 INCHES OF SNOW IN A 12 HOUR
PERIOD AND THIS ESTIMATE IS ON PAR WHEN USING AN AVERAGE OF MODEL
TOTAL QPF BTWN 00Z WED AND 00Z THURSDAY ALONG WITH SLR/S AROUND 12:1
/LIMITED LIFT OCCURRING IN THE HIGH DGZ WELL ABOVE H7/.
OVERALL SEEMS LIKE FAR WEST CWA WILL SEE THE MOST SNOW FROM THIS
SYSTEM BY WEDNESDAY EVENING AS H7 FGEN THAT IMPACTS THAT AREA TODAY
MAY PROVIDE A FOCUS FOR ADDITIONAL SNOW LATER TONIGHT THROUGH MUCH
OF WEDNESDAY AS LARGER SCALE FORCING FM MAIN SHORTWAVE IMPACTS THE
AREA AS SHOWN BY SWATH OF MODERATE H85-H7/H7-H5 Q-VECTOR CONVERGENCE
AND PERSISTENT DIVERGENCE ALOFT WITHIN RIGHT ENTRANCE OF H3 JET OVER
NORTHERN ONTARIO AND QUEBEC. ADDITIONALLY...THERE ARE INDICATIONS
THAT SNOW TIED TO FGEN AREA WOULD BE ENHANCED OVER THE NORTHWEST
CWA VCNTY OF KEWEENAW AS PRESENCE OF FS CONVERGENCE SUGGESTS THE
SNOW BAND WILL PIVOT OVER THAT AREA AS IT LIFTS NORTH THEN MOVES
EAST /RESULTING IN MODERATE SNOW POSSIBLY PERSISTING INTO EARLY
WEDNESDAY EVENING/. FARTHER TO THE EAST OVER THE REST OF THE CWA
IT GETS TRICKY TO FIGURE HOW MUCH SNOW MAY OCCUR...ESPECICALLY OVER
THE CNTRL AS THAT AREA WOULD BE ON THE EASTERN SUBSIDENCE SIDE OF
THE FGEN OVER THE WEST AND NORTHWEST CWA. H7 FGEN DOES INCREASE
ACROSS CNTRL AND EASTERN CWA ON WEDNESDAY AS THE LARGER SCALE
FORCING IMPACTS THE AREA BUT WITH THE MINIMAL MOISTURE ADVECTION
WORKING INTO THE SYSTEM...QPF/SNOW AMOUNTS DO NOT LOOK TO GET OUT OF
HAND. ADVY SNOW AMOUNTS SEEM REASONABLE LATER TONIGHT THROUGH
WEDNESDAY.
HEADLINES...AFTER COORD WITH SHORT TERM FORECASTER AND SURROUNDING
OFFICES DECIDED ON AN ADVY FOR ENTIRE CWA. GIVEN UNCERTAINTY ON
WHERE STRONGER FGEN SNOW BAND REDEVELOPS TONIGHT INTO WEDNESDAY WILL
LET LATER SHIFTS ASSESS WHETHER UPGRADE TO WARNING IS NEEDED FOR ANY
PARTS OF CWA. START TIMES FOR ADVY VARY WITH FAR WEST BEGINNING
TODAY AND REST OF CWA COMING INTO THE ADVY LATER THIS EVENING AND
OVERNIGHT TONIGHT. RAN THE ADVY THROUGH EARLY WEDNESDAY EVENING MOST
AREAS...BUT DID PUSH IT THROUGH MIDNIGHT WEDNESDAY NIGHT OVER
NORTHEAST CWA WITH SNOW LINGERING ON BACK SIDE OF THE LOW PRESSURE
AND ALSO WITH GUSTY NW WINDS LEADING TO BLSN CLOSER TO LK SUPERIOR.
THURSDAY AND THURSDAY NIGHT...COULD SEE LINGERING LIGHT SNOW SHOWERS
NEAR LK SUPERIOR ON THURSDAY IN WAKE OF THE SYSTEM. ECMWF/GFS INDICATE
MOISTURE THROUGH H9 WITH H9 TEMPS AROUND -10C. SLIGHT CHANCES WILL
COVER THIS POTENTIAL. HIGH PRESSURE RIDGE CROSSES THURSDAY NIGHT AND
DOES NOT APPEAR THAT MID-HIGH CLOUDS WILL ARRIVE AHEAD OF NEXT SYSTEM
UNTIL LATE THURSDAY NIGHT OVER THE WEST. TEMPS MAY DIVE TOWARD ZERO
OR EVEN BLO OVER INTERIOR SECTIONS WITH THE FRESH SNOW COVER AND CALM
CONDITIONS. NW WINDS BLO H9 MAY KEEP TEMPS SLIGHTLY WARMER NEAR LK
SUPERIOR.
REST OF EXTENDED...GFS STILL FARTHER NORTH COMPARED TO ECMWF AND
GEM-NH WITH SHORTWAVE/SFC TROUGH SLIDING ACROSS WESTERN GREAT LAKES
FRIDAY INTO FRIDAY EVENING. SLIGHT CHANCES FOR MOST AREAS...BUT HAVE
A BIT HIGHER ALONG WISCONSIN BORDER. COLD FRONT WORKS THROUGH LATER
FRIDAY NIGHT INTO SATURDAY AS NORTHERN STREAM WAVE DROPS THROUGH.
ENOUGH MID LEVEL MOISTURE TIED TO THE WAVE/COLD FRONT TO HAVE SOME
SMALLER CHANCES IN FOR MAINLY NORTH HALF OF CWA. WITH H85 TEMPS
DROPPING BLO -20C ON SATURDAY AND WITH LINGERING FORCING STILL
AROUND...LIKED PREVIOUS SHIFTS LIKELY POPS FOR NW AND NCNTRL CWA ON
SATURDAY FOR POTENTIAL OF LAKE ENHANCED SNOW SHOWERS. LARGE HIGH
PRESSURE BUILDS IN FOR SUNDAY LEADING TO DRY AND VERY CHILLY WEATHER.
HIGH TEMPS ON SUNDAY FORECAST TO BE IN THE TEENS TO MID 20S...WHICH
WOULD END UP CLOSE TO 20 DEGREES BLO NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 734 AM EDT TUE MAR 18 2014
A BAND OF SN WL BRING A PERIOD OF IFR CONDITIONS TO THE TAF SITES
THIS MRNG. THE MOST PERSISTENT IFR CONDITIONS WL IMPACT IWD AND
CMX...FARTHER FM DRIER AIR ADVANCING INTO UPR MI FM THE S AND WHICH
WL IMPACT SAW BY NOON. WITH THE ARRIVAL OF THIS DRIER AIR...EXPECT
CONDITIONS TO IMPROVE TO MVFR AND PERHAPS VFR LATER THIS AFTN INTO
THIS EVNG. AS LO PRES IN THE PLAINS MOVES TO THE E TNGT...MORE
WIDESPREAD SN WL ARRIVE AND LOWER CONDITIONS TO IFR AGAIN...MAINLY
AT IWD AND CMX. LINGERING DRY AIR CLOSER TO SAW MAY SLOW DOWN THIS
TREND THERE UNTIL AFT 12Z WED.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 524 AM EDT TUE MAR 18 2014
E-SE WINDS UP 20 KTS THIS MORNING WILL BACK TO THE N-NE AND INCREASE
TO UP TO 25-30 KTS BY WED AS A LO PRES IN THE PLAINS MOVES TO THE
LOWER GREAT LAKES. THE PASSAGE OF A HI PRES RIDGE/FLATTER PRES
GRADIENT IN ITS WAKE WILL RESULT IN DIMINISHING AND BACKING WINDS TO
THE S INTO FRI. AFTER ANOTHER LOW SHIFTS TO THE EAST THROUGH THE
LOWER GREAT LAKES ON FRI AND ANOTHER CANADIAN HIGH PRESSURE BUILDS
INTO THE NORTHERN PLAINS...A STRONGER N-NW WIND UP TO 25-30 KTS WILL
DEVELOP LATE FRI INTO SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 2 AM WEDNESDAY TO MIDNIGHT EDT
WEDNESDAY NIGHT FOR MIZ006-007-085.
WINTER WEATHER ADVISORY FROM 11 PM EDT /10 PM CDT/ THIS EVENING
TO 8 PM EDT /7 PM CDT/ WEDNESDAY FOR MIZ004-005-010-011-084.
WINTER WEATHER ADVISORY UNTIL 8 PM EDT /7 PM CDT/ WEDNESDAY FOR
MIZ001>003-009.
WINTER WEATHER ADVISORY FROM 2 AM EDT /1 AM CDT/ TO 8 PM EDT /7
PM CDT/ WEDNESDAY FOR MIZ012>014.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
947 AM MDT TUE MAR 18 2014
.UPDATE...
UPPER LOW THAT BROUGHT HEAVY SNOW TO THE BEARTOOTHS/ABSAROKAS...
FOOTHILLS AND SHERIDAN COUNTY WAS S OF THE AREA THIS MORNING PER
SATELLITE IMAGERY AND UPPER AIR OBSERVATIONS. THE SYSTEM LEFT A
500 MB COLD POCKET IN ITS WAKE AS WELL AS SOME TRAILING VORTICITY
OVER W MT. A FEW SNOW SHOWERS LINGERED OVER THE MOUNTAINS AS WELL
PER RADAR IMAGERY AND WEB CAMS. THE TRAILING SHORTWAVE WAS
GENERATING AN AREA OF CONVECTIVE SNOW SHOWERS NEAR GREAT FALLS PER
RADAR IMAGERY AT 1530Z. MODELS BROUGHT THE WAVE THROUGH THE
FORECAST AREA THIS AFTERNOON THROUGH TONIGHT. INTERESTINGLY...THERE
WERE SEVERAL INDICATORS POINTING AT THE POSSIBILITY OF THUNDER
THIS AFTERNOON OVER THE FORECAST AREA. RAP SOUNDINGS SHOWED
SEVERAL HUNDRED J/KG OF CAPE AND THE SSEO INDICATED AN AREA OF A
40 PERCENT CHANCE OF THUNDER NEAR KBIL. THE GFS AND WRF SOUNDINGS
DID NOT SHOW MUCH CAPE AT ALL BUT WERE UNSTABLE. GIVEN THE
INSTABILITY AND THE APPROACHING WAVE WOULD AT LEAST EXPECT
CONVECTIVE RAIN AND SNOW SHOWERS OVER THE AREA THROUGH THIS
EVENING. DID REMOVE PRECIPITATION CHANCES FROM ROSEBUD COUNTY E
THROUGH 18Z AS WAVE WILL NOT ARRIVE UNTIL LATER TODAY. MODELEDPOPS
AFTER THE WRF FORECAST GIVEN THE CONVECTIVE NATURE OF THE
PRECIPITATION AND DID MENTION ISOLATED THUNDER GIVEN THE ABOVE.
WILL KEEP THUNDER MENTION TO JUST THE AFTERNOON FOR NOW AND
MONITOR IN CASE IT NEEDS TO BE ADDED FOR THE EVENING. RAISED
TEMPERATURES SLIGHTLY BASED ON MIXING BETWEEN 850 AND 700 MB.
WINDS WERE IN GOOD SHAPE. ARTHUR
&&
.SHORT TERM...VALID FOR TDY AND WED...
SNOW IS TRENDING DOWN THIS MORNING AS UPPER LEVEL LOW SHIFTS INTO
SOUTHEAST WYOMING TAKING UPPER LEVEL DIFFLUENCE WITH IT. STILL
HAVE UPSLOPE NORTH-NORTHWEST WINDS TO DEAL WITH FOR A WHILE LONGER
BUT OVERALL SEEING SIGNIFICANT IMPROVEMENT OVER CONDITIONS AT
MIDNIGHT. HAVE DROPPED ALL THE WINTER WEATHER ADVISORIES FOR THE
AREA...BUT HOLDING ONTO WINTER STORM WARNINGS FOR SHERIDAN COUNTY
AND THE BEARTOOTH FOOTHILLS FOR A BIT LONGER. UPSLOPE WINDS INTO
THESE AREAS SHOULD KEEP MODERATE SNOW AND BLOWING SNOW GOING A BIT
LONGER. ANTICIPATE BEING ABLE TO DROP THESE WARNINGS BY SUNRISE IF
CURRENT TRENDS CONTINUE. ROAD CONDITIONS REMAIN DIFFICULT IN MANY
AREAS WITH A MIX OF WET AND SNOWPACKE/ICY CONDITIONS...AND AS OF 4
AM I90 WAS STILL CLOSED IN SHERIDAN COUNTY BETWEEN SHERIDAN AND
BUFFALO. MANY STRETCHES OF ROADWAY WILL BE WET IN THE VALLEYS
WITH ICY CONDITIONS ON HILLTOPS SO BE VERY CAREFUL DRIVING THIS
MORNING UNTIL ROADS WARM UP LATER THIS MORNING.
FOR THIS AFTERNOON WILL SEE UNSTABLE CONDITIONS COMBINED WITH A
COUPLE OF WEAK DISTURBANCES PUSHING THROUGH GENERATE SCATTERED
SNOW/RAIN SHOWERS AND WINDS WILL BE GUSTY AT TIMES...THOUGH MUCH
WEAKER THAN MONDAYS GUSTS. ANY SNOW ACCUMULATION WILL BE LIGHT AND
CONFINED TO THE HIGHER ELEVATIONS. RIDGING BUILDS IN FOR TONIGHT
WITH DRY AND COOL CONDITIONS. RIDGE KEEPS DRY CONDITIONS IN
PLACE FOR WEDNESDAY WITH WARMER TEMPERATURES ON TAP...BUT THE NEXT
STORM SYSTEM IS ON THE DOORSTEP. THIS WILL BRING INCREASING CLOUD
COVER FROM THE WEST ALONG WITH INCREASING WESTERLY WINDS IN THE
AFTERNOON THROUGH WEDNESDAY NIGHT. CHAMBERS
.LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON...
MODELS CONTINUE IN PRETTY GOOD AGREEMENT THROUGH THE EXTENDED
PERIOD...FAVORING A COOLER AND PROGRESSIVE PATTERN. GREATEST
CHANGES THIS MORNING CENTERED AROUND COOLING OFF THE EXTENDED
PERIOD. GUIDANCE HAS COME IN MUCH COOLER ACROSS THE BOARD THROUGH
THE EXTENDED PERIOD...RESULTING IN BELOW NORMAL TEMPS THROUGHOUT
THE EXTENDED PERIOD.
ANOTHER FAST MOVING PACIFIC COLD FRONT RUNS THROUGH THE REGION
WITH STRONG...GUSTY NW WINDS ON THURSDAY. POTENTIAL FOR MOUNTAIN
SNOWS AND LOWER ELEVATION MIXED PRECIP REMAINS CONSISTENT IN
MODELS...WITH GOOD UPPER LEVEL DYNAMICS AND INSTABILITY.
DOWNSLOPING FLOW MAY BE AN ISSUE IN THE WEST...BUT STILL CANNOT
RULE OUT POTENTIAL. RAISED POPS ONCE AGAIN...IN RESPONSE TO
MODEL CONSISTENCY. THIS SYSTEM USHERS A POLAR AIRMASS INTO THE
REGION THURSDAY NIGHT AND INTO FRIDAY.
THE POLAR AIRMASS REMAINS IN PLACE OVER THE REGION...WITH
PERSISTENT UNSETTLED NORTHWEST FLOW THROUGH THE REMAINDER OF THE
EXTENDED PERIOD. THE FIRST OF SEVERAL SHORTWAVES SLIDING THROUGH
THE FLOW ARRIVES QUICKLY ON THE HEALS OF THE COLD
FRONT...COMBINING WITH TROWAL TYPE FEATURE IN THE EAST. THIS ADDED
LIFT...COMBINED WITH 850 MB TEMPS AROUND -10C SHOULD GENERATE WIDESPREAD
SNOW SHOWERS/LIGHT SNOW. UPSLOPE FLOW AND OROGRAPHIC EFFECTS
DEVELOPING FRIDAY MORNING SHOULD ENHANCE SNOW POTENTIAL FOR CENTRAL
AND WEST ZONES. HIGHS FRIDAY ARE ONLY EXPECTED TO REACH THE LOW
30S.
UNSTABLE NORTHWEST FLOW REMAINS IN PLACE THROUGH SATURDAY...WITH
SHORTWAVES BRINGING REINFORCING SHOTS OF COOL AIR AND ADDITIONAL
LIFT TO THE SYSTEM. THIS WILL ALLOW COLD TEMPERATURES AND SNOW
TO LINGER THROUGH SATURDAY. WEAK RIDGING WILL SLIDE THROUGH THE
NORTHWEST FLOW ON SUNDAY...ALLOWING FOR A SHORT PERIOD OF DRY
CONDITIONS AND WARMER TEMPS...BUT ONLY TO LOW 40S.
ANOTHER SURGE OF COLD CANADIAN AIR AND UNSETTLED WEATHER EARLY
NEXT WEEK...WITH THE POTENTIAL FOR MORE SNOW FOR MONDAY AND
TUESDAY. MODELS HAVE BEEN VARYING WITH PLACEMENT OF THE UPPER
RIDGE FROM RUN TO RUN. CURRENT PROGGS KEEP THE RIDGE TO THE
WEST...KEEPING PERSISTENT UNSETTLED NORTHWEST FLOW...AND COLD AIR
IN THE REGION. FOR NOW HAVE INTRODUCED CHANCE POPS ACROSS WEST AND
CENTRAL ZONES FOR MONDAY AND TUESDAY. WE WILL NEED TO KEEP AN EYE
ON LOCATION AND AMPLIFICATION OF RIDGE IN LATER SHIFTS. AAG
&&
.AVIATION...
AREAS OF IFR/MVFR CEILINGS WILL GRADUALLY DISSIPATE THIS MORNING
ACROSS THE EAST...INCLUDING NEAR KBHK AND KMLS. HOWEVER...A
DISTURBANCE WILL BRING SCATTERED RAIN AND SNOW SHOWERS TO MUCH OF
THE REGION LATE THIS MORNING THROUGH THIS EVENING...WITH MVFR/IFR
CONDITIONS AND BRIEF GUSTY WINDS POSSIBLE IN ANY SHOWER. ISOLATED
THUNDERSTORMS ARE ALSO POSSIBLE ACROSS WESTERN AND CENTRAL ROUTES
THIS AFTERNOON...INCLUDING NEAR KBIL. AREAS OF MOUNTAIN
OBSCURATION ARE LIKELY INTO THIS EVENING. STC
&&
.PRELIMINARY POINT TEMP/POPS...
TDY WED THU FRI SAT SUN MON
-------------------------------------------------------
BIL 041 027/049 032/040 023/030 016/031 022/043 023/037
4/T 30/B 34/W 33/J 22/J 12/W 43/J
LVM 036 022/042 027/035 018/028 010/030 018/043 022/034
3/W 20/B 44/W 33/J 22/J 22/W 32/J
HDN 043 027/049 031/041 024/032 014/032 021/043 022/039
4/T 30/B 24/W 44/J 22/J 12/W 33/W
MLS 044 028/050 031/042 025/030 015/029 021/041 022/037
3/T 30/B 24/W 54/J 22/J 12/W 22/J
4BQ 043 026/047 029/041 024/031 015/030 020/042 022/037
3/T 30/B 13/W 44/J 22/J 12/W 32/W
BHK 042 026/046 028/043 022/029 013/026 018/036 019/034
2/T 30/B 14/W 55/J 22/J 12/J 22/J
SHR 037 020/044 025/039 021/031 011/030 017/044 019/038
3/T 30/B 13/W 33/J 23/J 12/W 33/J
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1103 AM CDT TUE MAR 18 2014
.UPDATE...
ISSUED AT 1101 AM CDT TUE MAR 18 2014
SNOW CONTINUES TO STRUGGLE TO ACCUMULATE OUTSIDE OF HEAVIER
BANDS. HOWEVER IN THE HEAVY BANDS THE VISIBILITY FALLS BELOW ONE
MILE...AND AT TIMES NEAR ZERO...AND ACCUMULATION IS OCCURRING.
SNOWFALL RATES OF GREATER THAN 1 INCH AN HOUR IS ABLE TO OVERCOME
THE MELTING. AS THE BANDS CONTINUE TO MIGRATE LATE THIS MORNING
AND EARLY THIS AFTERNOON...LOCALLY AMOUNTS AROUND 6 INCHES ARE
LIKELY. TEMPS ARE CONTINUING TO FALL AND EXPECT THE SNOW AND
BLOWING SNOW TO NOW IMPACT CUSTER AND FRONTIER COUNTIES SO
EXPANDED THE WINTER WX ADV...REPLACING THE WIND ADVISORY. LATE
THIS AFTERNOON INTO THE EVENING AS THE SNOW DIMINISHES FROM NW TO
SE...ROAD CONDITIONS SHOULD IMPROVE QUICKLY AS THE SNOW MELTS
FROM HIGHER SUN ANGLE AND A WARM GROUND...REMEMBER IT WAS AROUND
70 YESTERDAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT TUE MAR 18 2014
THE MODELS APPEAR TO BE SHOWING A HIGH DEGREE OF UNPREDICTABILITY
WITH THE STORM BEARING DOWN ON WRN AND NCNTL NEB THIS MORNING.
SEVERAL HIGHWAYS INCLUDING PARTS OF I-90/I-80 IN WYOMING NEAR
SHERIDAN...CASPER...LARAMIE AND CHEYENNE ARE CLOSED AND THE NUMBER
OF CLOSURES HAS BEEN RAPIDLY INCREASING SINCE MIDNIGHT. THE RAP13
AND 06Z NAM ARE HAMMERING SCNTL NEB WITH TROWAL AND THE RAP40 SHOWS
STRONG PETTERSON FGEN AT BOTH H850-700MB AND H700-500MB SUGGESTING
DEEP MOISTURE POOLING AND THE FORMATION OF A BARRIER JET ASSOCIATED
WITH 50KT-60KT WINDS BELOW 700MB. BOTH THE NAM AND RAP13 INDICATE
0.75 INCHES OF QPF DEVELOPING AS THIS BAND SETS UP THIS MORNING
ACROSS SCNTL NEB. THUS IN CONJUNCTION WITH THE ECM...IT WOULD APPEAR
THE HEAVY SNOW ACROSS WY WILL TRANSLATE EAST THRU WRN AND SCNTL NEB
TODAY. A WINTER WINTER WEATHER ADVISORY REPLACES THE WIND ADVISORY
IN ALL AREAS EXCEPT CUSTER AND FRONTIER COUNTY WHERE TEMPERATURES
ARE EXPECTED TO BE IN THE MID AND UPPER 30S TODAY. THE SUPER
ENSEMBLE TEMPERATURE FORECAST CLUSTERS NORTH PLATTE IN THE LOW TO
MID 30S LATE THIS MORNING AND THIS AFTERNOON.
THE ECM...NAM AND RAP13 WERE USED FOR THE QPF FORECAST WITH A 7 TO 1
SNOW RATIO FOR AROUND 3 INCHES OF SNOW CENTERED OVER LINCOLN COUNTY
NORTH AND SOUTH ALONG HIGHWAY 83. THE MODELS WILL LIKELY MOVE THIS
CENTER AROUND TODAY PERHAPS FARTHER WEST OR EAST OR EVEN SOUTH
DEPENDING ON HOW THE DYNAMICS COME TOGETHER. AT 08Z THE SFC LOW WAS
CENTERED OVER THE OKLAHOMA PANHANDLE AT 990 MB AND IS FORECAST TO
LIFT SLOWLY NORTHEAST TODAY AT AROUND 14KT. THIS SUPPORTS WIND
ADVISORY CONDITIONS WITH GUSTS TO 50 TO 55 MPH. GIVEN THE COMPACT
NATURE OF THE STORM AND THE RELATIVELY FAST MOTION...A PERIOD OF
HARSH WINTER WEATHER SHOULD DEVELOP LASTING 4 TO 8 HOURS. THE HRRR
INDICATES VISIBILITY FALLING TO 1/2 MILE. THE RAP AND NAM INDICATE
PCPN RATES NEAR OR ABOVE 0.10 INCH PER HOUR WHICH IS MODERATE TO
PERHAPS HEAVY SNOW.
THE SNOW SHOULD EXIT THE FORECAST AREA EARLY THIS EVENING THE SFC
LOW SHOULD OVER NRN IL BY WEDNESDAY MORNING. WINDS THIS EVENING
SHOULD DIMINISH AS SKIES CLEAR AND DECOUPLING OCCURS. LOWS TONIGHT
FALL INTO THE 20S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 354 AM CDT TUE MAR 18 2014
GENERAL NORTHWEST FLOW ALOFT CONTINUES UNCHANGED THROUGH THE PERIOD.
SEVERAL UPPER LEVEL DISTURBANCES WILL BE EMBEDDED WITHIN THE FLOW.
DUE TO CONTINUED LIMITED MOISTURE AND THE WEAK NATURE OF THE
SYSTEMS...I AM HESITANT TO INTRODUCE MUCH IN THE WAY OF POPS INTO
THE FORECAST. APPEARS SATURDAY WILL BE THE BEST SHOT FOR US TO
RECEIVE SOME LIGHT PRECIP...AND HAVE INTRODUCED A SLIGHT CHANCE FOR
RAIN OR SNOW SHOWERS.
TEMPERATURE WISE...THE WARMEST DAY WILL BE THURSDAY...AS A THERMAL
RIDGE QUICKLY BUILDS ACROSS THE AREA AHEAD OF A COLD FRONT SET TO
ARRIVE FRIDAY. HIGH PRESSURE...ORIGINATING FROM THE ARCTIC...WILL
BUILD SOUTH INTO THE NORTHERN PLAINS BEHIND THE FRONT DURING THE
WEEKEND...KEEPING TEMPERATURES BELOW NORMAL. A REINFORCING ARCTIC
HIGH PRESSURE CENTER BUILDS SOUTH INTO THE PLAINS EARLY NEXT
WEEK...WITH CONTINUED BELOW NORMAL TEMPERATURES. IN FACT...THE
LATEST RUN OF THE ECMWF MODEL INDICATES 850MB TEMPERATURES OF -10C
TO -15C BY WEDNESDAY MORNING ACROSS THE AREA. LONG STORY
SHORT...WINTER WILL CONTINUE TO HOLD IT/S GRIP DESPITE THE OFFICIAL
ARRIVAL OF SPRING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 612 AM CDT TUE MAR 18 2014
IFR/LIFR BECOMES WIDESPREAD AS AN AREA OF STRONG WINDS AND SNOW
MOVE THROUGH THE FCST AREA TODAY. THIS SNOW IS CURRENTLY MOVING
THROUGH SWRN SD AND ERN WY AND ENTERING WESTERN NEB.
FLIGHT CONDITIONS BEGIN TO IMPROVE FROM NORTHWEST TO SOUTHEAST
THIS AFTERNOON WITH THE SNOW EXITING THE FCST AREA BY EARLY
EVENING. WINDS TODAY INCREASE TO 35028G45KT AND SUBSIDE LATE THIS
AFTERNOON AND EARLY THIS EVENING AS THE CLEARING LINE PROGRESSES
EAST.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING
FOR NEZ004>010-022>029-035>038-056>059-069>071-094.
&&
$$
UPDATE...MASEK
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
612 AM CDT TUE MAR 18 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT TUE MAR 18 2014
THE MODELS APPEAR TO BE SHOWING A HIGH DEGREE OF UNPREDICTABILITY
WITH THE STORM BEARING DOWN ON WRN AND NCNTL NEB THIS MORNING.
SEVERAL HIGHWAYS INCLUDING PARTS OF I-90/I-80 IN WYOMING NEAR
SHERIDAN...CASPER...LARAMIE AND CHEYENNE ARE CLOSED AND THE NUMBER
OF CLOSURES HAS BEEN RAPIDLY INCREASING SINCE MIDNIGHT. THE RAP13
AND 06Z NAM ARE HAMMERING SCNTL NEB WITH TROWAL AND THE RAP40 SHOWS
STRONG PETTERSON FGEN AT BOTH H850-700MB AND H700-500MB SUGGESTING
DEEP MOISTURE POOLING AND THE FORMATION OF A BARRIER JET ASSOCIATED
WITH 50KT-60KT WINDS BELOW 700MB. BOTH THE NAM AND RAP13 INDICATE
0.75 INCHES OF QPF DEVELOPING AS THIS BAND SETS UP THIS MORNING
ACROSS SCNTL NEB. THUS IN CONJUNCTION WITH THE ECM...IT WOULD APPEAR
THE HEAVY SNOW ACROSS WY WILL TRANSLATE EAST THRU WRN AND SCNTL NEB
TODAY. A WINTER WINTER WEATHER ADVISORY REPLACES THE WIND ADVISORY
IN ALL AREAS EXCEPT CUSTER AND FRONTIER COUNTY WHERE TEMPERATURES
ARE EXPECTED TO BE IN THE MID AND UPPER 30S TODAY. THE SUPER
ENSEMBLE TEMPERATURE FORECAST CLUSTERS NORTH PLATTE IN THE LOW TO
MID 30S LATE THIS MORNING AND THIS AFTERNOON.
THE ECM...NAM AND RAP13 WERE USED FOR THE QPF FORECAST WITH A 7 TO 1
SNOW RATIO FOR AROUND 3 INCHES OF SNOW CENTERED OVER LINCOLN COUNTY
NORTH AND SOUTH ALONG HIGHWAY 83. THE MODELS WILL LIKELY MOVE THIS
CENTER AROUND TODAY PERHAPS FARTHER WEST OR EAST OR EVEN SOUTH
DEPENDING ON HOW THE DYNAMICS COME TOGETHER. AT 08Z THE SFC LOW WAS
CENTERED OVER THE OKLAHOMA PANHANDLE AT 990 MB AND IS FORECAST TO
LIFT SLOWLY NORTHEAST TODAY AT AROUND 14KT. THIS SUPPORTS WIND
ADVISORY CONDITIONS WITH GUSTS TO 50 TO 55 MPH. GIVEN THE COMPACT
NATURE OF THE STORM AND THE RELATIVELY FAST MOTION...A PERIOD OF
HARSH WINTER WEATHER SHOULD DEVELOP LASTING 4 TO 8 HOURS. THE HRRR
INDICATES VISIBILITY FALLING TO 1/2 MILE. THE RAP AND NAM INDICATE
PCPN RATES NEAR OR ABOVE 0.10 INCH PER HOUR WHICH IS MODERATE TO
PERHAPS HEAVY SNOW.
THE SNOW SHOULD EXIT THE FORECAST AREA EARLY THIS EVENING THE SFC
LOW SHOULD OVER NRN IL BY WEDNESDAY MORNING. WINDS THIS EVENING
SHOULD DIMINISH AS SKIES CLEAR AND DECOUPLING OCCURS. LOWS TONIGHT
FALL INTO THE 20S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 354 AM CDT TUE MAR 18 2014
GENERAL NORTHWEST FLOW ALOFT CONTINUES UNCHANGED THROUGH THE PERIOD.
SEVERAL UPPER LEVEL DISTURBANCES WILL BE EMBEDDED WITHIN THE FLOW.
DUE TO CONTINUED LIMITED MOISTURE AND THE WEAK NATURE OF THE
SYSTEMS...I AM HESITANT TO INTRODUCE MUCH IN THE WAY OF POPS INTO
THE FORECAST. APPEARS SATURDAY WILL BE THE BEST SHOT FOR US TO
RECEIVE SOME LIGHT PRECIP...AND HAVE INTRODUCED A SLIGHT CHANCE FOR
RAIN OR SNOW SHOWERS.
TEMPERATURE WISE...THE WARMEST DAY WILL BE THURSDAY...AS A THERMAL
RIDGE QUICKLY BUILDS ACROSS THE AREA AHEAD OF A COLD FRONT SET TO
ARRIVE FRIDAY. HIGH PRESSURE...ORIGINATING FROM THE ARCTIC...WILL
BUILD SOUTH INTO THE NORTHERN PLAINS BEHIND THE FRONT DURING THE
WEEKEND...KEEPING TEMPERATURES BELOW NORMAL. A REINFORCING ARCTIC
HIGH PRESSURE CENTER BUILDS SOUTH INTO THE PLAINS EARLY NEXT
WEEK...WITH CONTINUED BELOW NORMAL TEMPERATURES. IN FACT...THE
LATEST RUN OF THE ECMWF MODEL INDICATES 850MB TEMPERATURES OF -10C
TO -15C BY WEDNESDAY MORNING ACROSS THE AREA. LONG STORY
SHORT...WINTER WILL CONTINUE TO HOLD IT/S GRIP DESPITE THE OFFICIAL
ARRIVAL OF SPRING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 612 AM CDT TUE MAR 18 2014
IFR/LIFR BECOMES WIDESPREAD AS AN AREA OF STRONG WINDS AND SNOW
MOVE THROUGH THE FCST AREA TODAY. THIS SNOW IS CURRENTLY MOVING
THROUGH SWRN SD AND ERN WY AND ENTERING WESTERN NEB.
FLIGHT CONDITIONS BEGIN TO IMPROVE FROM NORTHWEST TO SOUTHEAST
THIS AFTERNOON WITH THE SNOW EXITING THE FCST AREA BY EARLY
EVENING. WINDS TODAY INCREASE TO 35028G45KT AND SUBSIDE LATE THIS
AFTERNOON AND EARLY THIS EVENING AS THE CLEARING LINE PROGRESSES
EAST.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 10 AM CDT /9 AM MDT/ THIS MORNING
TO 7 PM CDT /6 PM MDT/ THIS EVENING FOR NEZ056>059-069-070.
WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING
FOR NEZ004>010-022>029-035>037-094.
WIND ADVISORY FROM 10 AM THIS MORNING TO 9 PM CDT THIS EVENING
FOR NEZ038-071.
&&
$$
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
1002 AM PDT Tue Mar 18 2014
.Synopsis...
Areas of breezy north and east winds will continue this morning,
otherwise dry weather and lighter winds are expected through the
remainder of the week.
&&
.Discussion...
A few gusty spots in the Valley and Sierra this morning due a
pressure gradient set up by a weak shortwave trough passing to the
northeast. While the RUC13 shows this trough passing just to the
NE of the Lassen area by 11am, satellite imagery indicates a dry
airmass associated with it as skies remain mostly clear in that
area (except for a few low clouds in extreme NE CA).
While several sites in the Northern Sacramento Valley including
KRDD and KRBL are nearing or just reaching wind advisory criteria
this morning, the pressure gradients are expected to relax by
around 11am, meaning the current winds are likely the strongest of
the day. Thus, have opted to not issue an advisory which would be
marginal and only last a couple hours. Expecting gusty northeast
to east winds over the Sierra as well through the early afternoon.
Have updated the forecast through this afternoon to better
reflect current winds. Otherwise, previous forecast remains on
track. -DVC
.Previous Discussion... issued at 330 AM PDT...
Breezy north winds continue across the region early this morning
as pressure gradients remain tight (MFR to SAC is still around 13
mbs). Some high clouds continue to brush by associated with weak
passing waves, otherwise skies are clear. Temperatures are a mixed
bag early this morning with wind- sheltered areas tending to see
much cooler readings early this morning while some windy spots are
actually a little warmer than 24 hours ago.
Short-wave ridging will move over the region, and coupled with
weakening pressure gradients will result in lighter winds by this
afternoon. Temperatures will likely moderate a bit, but will still
be cool compared to the readings we saw over the weekend.
Not a whole lot of change is expected through the remainder of the
week as the dry pattern continues with northwesterly flow aloft.
Another short-wave is forecast to pass to the north on Thursday
and we may see an increase in northerly winds again in its wake.
&&
.Extended Discussion (Saturday through Tuesday)
Upper level ridging will bring more warm and dry conditions
through Monday, with above normal high temperatures. Confidence is
improving for a change to a wetter, unsettled pattern next week. Models
continue show a wet system impacting NorCal starting on Tuesday or
Tuesday evening and continuing through Wednesday. The ECMWF
continues the trend of slower and deeper, which could keep
precipitation going into Thursday. The GFS is more progressive,
with an early onset of precipitation Monday morning, with lighter
lingering activity through mid week. Have increased pops
Tuesday/Tuesday into chance category with increasing confidence. Snow
levels look rather high at this point. The development of this
system will be closely watched over coming days.
&&
.Aviation...
Prevailing VFR conditions as high pressure continues to build
inland through OR into the Great Basin. Areas northerly surface
gusts 25-35 kts possible today in the Sac Valley, mainly N and W
sides, decreasing after 00z Wed. Elsewhere, areas N to E surface
wind gusts 25-40 knots possible over coastal mountains and eastern
foothill and mountains including western Plumas and northern
Sierra Nevada through Wed morning.
&&
.STO Watches/Warnings/Advisories...
None.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1109 AM CDT TUE MAR 18 2014
.DISCUSSION...
312 AM CDT
OTHER THAN TODAY...EARLY WEDNESDAY MORNING...AND POTENTIALLY FRIDAY
(ESPECIALLY SOUTHERN CWA) THE UNRELENTING WINTER OF 2013-14 LOOKS
POISED TO KEEP GOING AD NAUSEUM.
PAIR OF LOW PRESSURES OVER THE CENTRAL AND SOUTHERN PLAINS WILL
CONSOLIDATE INTO A SINGLE FAIRLY DEEP LOW THAT WILL TRACK EAST
TOWARD KANSAS CITY BY EARLY EVENING. WARM AIR ADVECTION WILL
CONTINUE AND SHOULD RESULT IN A MILDER DAY TODAY...THOUGH EASTERLY
COMPONENT TO THE WINDS SHOULD RESULT IN COOLER CONDITIONS NEAR THE
CHICAGO LAKE FRONT AND NORTH SHORE. HIGH AND EVENTUALLY MID
CLOUDINESS WILL BE ON THE INCREASE TODAY BUT STILL SOME FILTERED
SUNSHINE IS EXPECTED...ESPECIALLY THIS MORNING.
SFC LOW WILL TRACK NE TO NEAR MKX BY 12Z WEDNESDAY...RESULTING IN
WINDS BECOMING SOUTH THIS EVENING WHICH WILL SHOVE THE MARINE LAYER
OFFSHORE LIKELY ALLOWING IL LAKESIDE AREAS TO REACH THEIR HIGH TEMPS
FOR THE DAY WELL AFTER DARK TONIGHT. THE SYSTEM TONIGHT WILL NOT
REALLY HAVE ACCESS TO GULF MOISTURE AS IT MOVES THROUGH...HOWEVER
COMBINATION OF COLD AIR ALOFT AND RESULTANT STEEP LAPSE RATES AND
STRONG LOW LEVEL JET THAT WILL BECOME COUPLED WITH THE LEFT EXIT
REGION OF 120-130KT 250MB JET SHOULD ALLOW FOR STRONG ASCENT. WOULD
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO BREAK OUT THIS EVENING
AND MOVE ACROSS THE CWA LATE THIS EVENING AND PARTICULARLY
OVERNIGHT.
SOME SHOWERS COULD LINGER INTO WEDNESDAY MORNING AS THE COLD FRONT
MOVES ACROSS THE AREA RESULTING IN WEDNESDAY TURNING BLUSTERY AND
COLDER WITH STEADY/SLOWLY FALLING TEMPS DURING THE DAY. LINGERING
LOW LEVEL MOISTURE AND STEEPENING LOW LEVEL LAPSE RATES COULD ALLOW
FOR SOME FLURRIES OR LIGHT SNOW SHOWERS WEDNESDAY AFTERNOON BUT NOT
ANTICIPATING ANY ACCUMULATION.
CONTINUED BELOW AVERAGE TEMPS EXPECTED THROUGH THURSDAY NIGHT. A
COUPLE OF FAIRLY LOW AMPLITUDE NW FLOW SHORTWAVE EXPECTED TO RIPPLE
ACROSS THE REGION THURSDAY NIGHT THROUGH FRIDAY NIGHT. THE SECOND
SYSTEM...ARRIVING FRIDAY AFTERNOON AND EVENING...LOOKS TO BE A BIT
MORE AMPLIFIED AND STANDS A BETTER CHANCE TO BRING SOME
PRECIPITATION TO THE AREA. ECMWF CONTINUES TO BE AT ODDS WITH THE
GFS/GEM REGARDING THE TRACK OF THE SFC LOW ON FRIDAY. FARTHER NORTH
TRACK DEPICTED BY GEM/GFS WOULD OFFER UP A DECENT CHANCE OF MOST OF
THE CWA BRIEFLY GETTING INTO THE WARM SECTOR AND ALLOWING TEMPS TO
REACH IF NOT GET A BIT ABOVE NORMAL. ECMWF TRACKS SFC LOW FARTHER
SOUTH AND WOULD KEEP WINDS OFF THE LAKE AND RESULT IN MUCH COLDER
TEMPS FRIDAY NORTH OF I-80. THE TRACK DIFFERENCES BETWEEN THE MODELS
IS SMALL AND REALLY LITTLE MORE THAN NOISE...BUT HAVE DRAMATICALLY
DIFFERENT RESULTS IN SENSIBLE WEATHER...PARTICULARLY OVER NORTHEAST
ILLINOIS. GOING TO SIDE WITH CLIMO AND KEEP TEMPS COLDER OVER
NORTHEAST ILLINOIS...BUT BUST POTENTIAL IS HIGH AND IF TRACK ENDS UP
BEING FARTHER NORTH THEN WE COULD BE PLEASANTLY SURPRISED WITH
MILDER TEMPERATURES. AT THIS POINT...SOUTHERN CWA LOOKS LIKELY TO BE
IN THE WARM SECTOR WITH HIGHS WELL INTO THE 50S.
THE FIRST OFFICIAL WEEKEND OF SPRING LOOKS TO BE ANYTHING BUT
SPRING-LIKE WITH UNSEASONABLY COLD AIR MOVING IN BEHIND THE SYSTEM
FRIDAY NIGHT INTO SATURDAY. THAT COLD BLAST LOOKS TO BE FOLLOWED UP
WITH AN EVEN COLDER AIR MASS WITH SECONDARY COLDER FRONT SUNDAY WITH
ECMWF/GFS/GFS ENSEMBLES AND GEM ALL BRINGING 850MB TEMPS DOWN INTO
THE -16 TO -19C RANGE SUNDAY AFTERNOON. LOOKING BACK AT REANALYSIS
DATA GOING BACK TO 1979...850MB TEMPS OF -16 OR COLDER WOULD BE
AMONG THE COLDEST 1 PERCENT OF READINGS FOR MAR 16-31ST...SO QUITE
IMPRESSIVE. HAVE SCALED BACK HIGHS A COUPLE DEGREES FROM MODEL
BLENDED INITIALIZATION...BUT WORTH NOTING THAT 4 OUT OF THE 6
PREVIOUS DAYS WITH 850MB TEMPS OF -16C OR COLDER IN LATE MARCH HAS
RESULTED IN HIGHS IN THE 20S IN CHICAGO AND THE OTHER 2 DAYS WERE
LOW 30S.
GFS/ECMWF CONTINUE TO ADVERTISE A NORTHWEST FLOW SHORT WAVE ARRIVING
AROUND MONDAY WHICH COULD BRING SNOW TO THE AREA...ONLY TO BE
FOLLOWED UP WITH LONG RANGE MODELS SUGGEST WILL BE AN EVEN COLDER
BLAST OF AIR NEXT WEEK. WHILE ITS STILL BEYOND THE 7 DAY FORECAST
PERIOD...RUN AFTER RUN THE ECMWF HAS BEEN ADVERTISING AN ARCTIC
BLAST THAT COULD POTENTIALLY THREATEN RECORDS NEXT WEEK AND NOW THE
GFS HAS JOINED THIS BAND CAMP. GIVEN THE STRONG AGREEMENT IN THE
MEDIUM RANGE MODELS AND THEIR ENSEMBLES IN DEVELOPING A STRONG REX
BLOCK OVER THE NORTHEAST PACIFIC NORTH INTO ALASKA THIS WEEKEND IT
WOULD SEEM TO BE HIGHLY LIKELY THAT GENERALLY MUCH BELOW AVERAGE
TEMPS WOULD CONTINUE THROUGH THE REST OF MARCH.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* GUSTY SE TO E WINDS TODAY.
* RAIN SHOWERS LIKELY AFT 05-06Z TONIGHT.
* CHANCE OF EMBEDDED TSRA MAINLY 08Z-11Z TONIGHT... PERHAPS
LASTING UNTIL 14Z.
* LOWER MVFR TO IFR CIGS LIKELY WITH THE RAIN LATE TONIGHT.
ED F
//DISCUSSION...UPDATED 12Z...
THE MAIN FORECAST CONCERNS DURING THE DAY TODAY WILL AGAIN BE THE
WINDS. A POTENT AREA OF LOW PRESSURE...CURRENTLY CENTERED ACROSS
THE PLAINS STATES...WILL BEGIN TO CONSOLIDATE AND TREK EASTWARD
ACROSS THE LOWER AND MID MISSOURI VALLEY LATER TODAY. THIS WILL
FAVOR AN EAST-SOUTHEASTERLY WIND COMPONENT...WITH GUSTS UP AROUND
20 KT...AT ALL THE TAF SITES THROUGH THE DAY.
THIS AREA OF SURFACE LOW PRESSURE...AND THE ACCOMPANYING MID LEVEL
DISTURBANCE WILL MOVE ACROSS NORTHERN ILLINOIS LATE TONIGHT
INTO EARLY WEDNESDAY MORNING. THIS TIMING CONTINUES TO FAVOR THE BEST
CHANCES FOR RAIN SHOWERS AND IFR CIGS ACROSS NORTHERN
ILLINOIS...MAINLY AFTER MIDNIGHT TONIGHT. THE MAIN CHANGE FOR THE
12 UTC TAFS WAS TO ADD A PROB 30 MENTION FOR SOME THUNDER LATER
TONIGHT. GIVEN THE COMBINATION OF SOME STEEP MID LEVEL LAPSE RATES
AND A PERIOD OF GOOD DYNAMIC FORCING FOR ASCENT WITHIN THE WARM
SECTOR OF THIS SYSTEM...IT APPEARS THAT SOME THUNDERSTORMS ARE
CERTAINLY POSSIBLE.
OTHERWISE...THE MAIN CONCERN LATER WEDNESDAY MORNING WILL BE THE ONSET
OF SOME STRONGER WESTERLY WINDS IN THE WAKE OF A COLD FRONTAL
PASSAGE...LIKELY BY LATE MORNING ON WEDNESDAY. IT APPEARS THAT THE WINDS
COULD GUST IN THE 30 TO 35 KT RANGE FOR A PERIOD WEDNESDAY
AFTERNOON FOLLOWING THIS COLD FRONTAL PASSAGE. THE MAIN PRECIP
THREAT SHOULD END DURING THE MORNING...WITH GRADUALLY IMPROVING CIGS
INTO THE AFTERNOON.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH FOR WIND FORECAST TODAY AND TONIGHT AND RAIN
SHOWER TIMING TONIGHT.
* LOW TO MEDIUM FOR A THUNDERSTORM IMPACTING THE TERMINALS AFTER
08 UTC WED.
ED F
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED
12Z...
WEDNESDAY NIGHT...BECOMING VFR.
THURSDAY...VFR.
FRIDAY...CHANCE OF -RA. MVFR CIGS POSSIBLE.
SATURDAY THROUGH SUNDAY...VFR.
MONDAY...CHANCE OF SNOW AND IFR.
KJB
&&
.MARINE...
328 AM CDT
THE MAIN FORECAST CONCERNS OVER THE LAKE CONTINUE TO CENTER AROUND
THE STORM SYSTEM EXPECTED TO MOVE ACROSS LAKE MICHIGAN WEDNESDAY
MORNING.
WINDS WILL CONTINUE OUT OF THE EAST ACROSS THE NORTHERN END OF THE
LAKE TODAY...WITH SOUTHEASTERLY WINDS EXPECTED TO CONTINUE ACROSS
THE SOUTHERN END OF THE LAKE. WIND SPEEDS APPEAR TO BE IN THE 15 TO
25 KT RANGE...WITH SOME GUSTS POSSIBLY APPROACHING 30 KT LATER TODAY
AND TONIGHT...ESPECIALLY ACROSS SOUTHERN LAKE MICHIGAN. THIS
SOUTHEASTERLY WIND COMPONENT WILL LIKELY ALLOW WAVES TO CONTINUE TO
BUILD TO AND JUST ABOVE 4 FT ACROSS MY FAR NORTHERN MARINE NEAR
SHORE ZONES ACROSS NORTHERN ILLINOIS. THEREFORE...I HAVE ISSUED A
SMALL CRAFT ADVISORY STARTING THIS AFTERNOON FOR AREAS FROM CHICAGO
NORTHWARD.
FOR THE REMAINDER OF MY NEAR SHORE ZONES I WILL START THE
ADVISORY LATER TONIGHT...AS THE WINDS PICK UP OUT OF THE
SOUTH-SOUTHWEST TOWARDS WEDNESDAY MORNING...IN RESPONSE TO THE
APPROACHING AREA OF LOW PRESSURE. THE SYSTEMS COLD FRONT IS THEN
EXPECTED TO PUSH ACROSS THE NEAR SHORE ZONES...ALONG WITH MUCH OF
SOUTHERN LAKE MICHIGAN DURING THE MORNING ON WEDNESDAY. IN THE WAKE
OF THIS FRONTAL PASSAGE...WINDS WILL BECOME WESTERLY AND INCREASE UP
AROUND 30 KT FOR THE REST OF THE DAY. I AM STILL CONCERNED THAT
THERE COULD BE SOME LOW END GALES AT TIMES DURING THIS
PERIOD...ESPECIALLY DIRECTLY IN THE WAKE OF THE FRONTAL PASSAGE.
THIS THREAT STILL ALSO APPEARS TO BE PRIMARILY ACROSS THE SOUTHERN
HALF OF THE LAKE. AT THIS TIME...I WILL MENTION THE POSSIBILITY FOR
SOME GALE FORCE GUSTS...RATHER THAN GOING WITH A GALE WATCH...AS IT
APPEARS THE GALE GUSTS MAY END UP BEING FAIRLY SHORT LIVED IN THE
WAKE OF THE COLD FRONT.
THE WINDS WILL GRADUALLY ABATE WEDNESDAY NIGHT INTO THURSDAY AS THE
STORM SYSTEM CONTINUES NORTHEASTWARD INTO CANADA. A PERIOD OF
LIGHTER WINDS WILL ENSUE AS A SURFACE RIDGE OF HIGH PRESSURE PUSHES
ACROSS THE LAKE ON THURSDAY. A SECOND STORM SYSTEM STILL LOOKS TO
IMPACT WINDS ACROSS THE LAKE LATER IN THE WEEK...WITH ANOTHER PERIOD
OF HIGHER NORTHERN WINDS POSSIBLE INTO THE FIRST PART OF THE
WEEKEND.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741...5 PM TUESDAY TO 10 PM
WEDNESDAY.
SMALL CRAFT ADVISORY...LMZ744-LMZ745...1 AM WEDNESDAY TO 4 AM
THURSDAY.
SMALL CRAFT ADVISORY...LMZ742-LMZ743...1 AM WEDNESDAY TO 10 PM
WEDNESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
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Area Forecast Discussion
National Weather Service Lincoln IL
1100 AM CDT Tue Mar 18 2014
.DISCUSSION...
ISSUED 1053 AM CDT Tue Mar 18 2014 by NWS Chicago
Main forecast tweaks for the afternoon were to the diurnal
temperature and dewpoint curves. Did not really change overall
highs but slowed the warming a bit in the east and southeast to
account for lingering cloud cover and better blend with trends
shown by the neighbors. Mid 50s highs will not come from advecting
cold air from under the cloudiness to the southeast, but from
lifting the low out of Kansas and pushing the warm and clear
sector over the area later today. May also need to update sky
grids as well to reflect this progression.
No changes to later periods at this time.
Lenning
&&
.AVIATION...
ISSUED 635 AM CDT Tue Mar 18 2014
Forecast concern will be movement of MVFR/IFR cigs over southern
Indiana this morning and how far west and northwest they move
this morning. Past few runs of the RAP and HRRR models suggest
our eastern TAF sites (KDEC and KCMI) may be affected by MVFR cigs
after 19z this afternoon. Otherwise, the remainder of the sites
will remain VFR thru the day. Look for increasing southeast to
south winds today with gusts up to 25 kts at times this afternoon.
A cold front will begin to approach the area tonight with winds
veering more into a south to southwest direction and decreasing in
speed later this evening. Because of the decrease in winds near
the surface, we may need to consider low level wind shear as winds
just off the surface will be from a 190-220 direction at around 40
kts. For now, will hold off including LLWS for this evening as
there is still some doubt how quickly sfc winds will diminish, if
at all, this evening. As the front moves across the area later
this evening, showers will increase some over the north with the
possibility for some isold TSRA. Will include VCTS at PIA, BMI and
CMI later this evening. Surface winds will veer more into the
southwest late tonight with speeds of 10 to 15 kts aftr 09z with
probabilities increasing for MVFR cigs as the storm system shifts
off to our northeast towards dawn Wednesday.
Smith
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Tue Mar 18 2014
SHORT TERM...Today through Friday night
00Z models are in fair agreement next few days and will use a
blend. One wx system to bring chance of rain showers tonight & Wed
with another one on tap for Fri and Fri night. A 3rd system
arrives Mon afternoon & Monday night with chance of rain/snow.
Extended models continue to trend colder during next work week
with coldest air arriving next Wed when 850 mb temps low to -15 to -20C.
CPC 8-14 day outlook for Mar 25-31 continue a 70% chance of below
normal temps over central IL with MN/WI/MI greater than 80% chance
of below normal temps. Central IL also has a 50% chance of above
normal precipitation. So winter like weather that develops during
next work week could linger through the rest of the month.
Strong 990 mb surface low pressure over central KS to lift ne
across northern IL overnight and across lower MI during Wed. This
to bring a cold front east across IL overnight. Increasing
sse winds ahead of approaching low pressure today with gusts to 30
mph this afternoon to warm temps into mid to upper 50s. Temps
currently are in the upper 20s and lower 30s. Models have trended
a few degrees cooler due to more mid/high clouds increasing from
the west today. Low stratus clouds should stay se of IL over KY
and southeast IN.
Have chance of rain showers spreading east across central IL
during the evening and into southeast IL by overnight. Added
isolated thunderstorms to northern areas tonight per SPC day 1
outlook with general risk of thunder over parts of central IL.
Models have trended slower and linger some light qpf over central
IL Wed with upper level trof moving into IL behind the cold front.
Have therefore increase chances of light rain showers Wed
especially from I-74 ne. Areas from Peoria north could see a few
light snow showers too Wed morning but no accumulations. Windy on
Wed with wsw wind gusts of 30 to 40 mph. If clouds break up during
the afternoon Wed could see higher wind gusts.
Dry conditions Wed night and Thu with highs in the 50s Thu with
more sunshine and increasing south winds Thu afternoon as high
pressure passes to the east of IL.
Nice warmup on Friday still expected with highs in the upper 50s
to mid 60s with breezy ssw winds and mildest temps in southeast IL.
Surface low pressure to track into central/northern IL Friday
afternoon and brings another cold front east through IL then with
next chance of rain showers Friday and Friday night. Have isolated
thunder over southeast IL Friday night.
LONG TERM...Saturday through Wednesday
Dry and cooler conditions expected this weekend. A 3rd wx system
to affect region Mon afternoon and Monday night with chance of
rain or snow showers and turning progressively colder from Mon
thru Wed.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1257 PM EDT TUE MAR 18 2014
.UPDATE...
AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 336 AM EDT TUE MAR 18 2014
AFTER A DRY MILD DAY TODAY...RAIN SHOWERS WILL DEVELOP LATE TONIGHT
INTO WEDNESDAY AS A COLD FRONT MOVES THROUGH. COOLER DRIER WEATHER
IS EXPECTED FOR WEDNESDAY NIGHT AND THURSDAY. TEMPERATURES WILL ONCE
AGAIN TURN WARMER FOR FRIDAY WITH THE PASSAGE OF A WARM FRONT. RAIN
AND EMBEDDED THUNDERSTORMS WILL ACCOMPANY THE PASSAGE OF LOW
PRESSURE FRIDAY NIGHT. HIGH PRESSURE THEN REESTABLISHES FOR THE
WEEKEND WITH DRY AND PROGRESSIVELY COLDER AIR.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1008 AM EDT TUE MAR 18 2014
AREA OF LOW CLOUDS OVER SOUTHERN INDIANA HAS BEEN EXPANDING
NORTHWEST DURING THE PAST FEW HOURS. PILOT REPORTS INDICATE THIS
CLOUD DECK IS QUITE THIN...SO EXPECTING THESE CLOUDS TO SCATTER OUT
THIS AFTERNOON. THINK PARTLY CLOUDY WILL STILL WORK OVERALL
TODAY...BUT THERE WILL PROBABLY BE A PERIOD OF MAINLY CLOUDY SKIES
THROUGH EARLY AFTERNOON...ESPECIALLY OVER THE SOUTHERN THROUGH WEST
CENTRAL ZONES.
THIS MORNING/S UPPER AIR SUGGEST TODAY/S HIGHS ARE WITHIN
REACH...BUT THEY WILL DEPEND ON HOW FAST LOW CLOUDS DISSIPATE. WILL
NOT MAKE ANY CHANGES AT THIS TIME...BUT THE HIGHS MAY NEED TO BE
LOWERED LATER TODAY WHEN LOW CLOUD TRENDS BECOME MORE APPARENT.
PREVIOUS DISCUSSION FOLLOWS.
HIGH CLOUDS DRIFTING THROUGH EARLY THIS MORNING WITH WEAK HIGH
PRESSURE ACROSS THE OHIO VALLEY. LARGE AREA OF STRATUS MOVING W/NW
ACROSS KENTUCKY AS WELL. WITH LIGHT E/SE FLOW...TEMPS RANGED FROM
THE MID 20S TO LOWER 30S ACROSS THE FORECAST AREA AT 07Z.
INITIAL ISSUE FOCUSES ON THE STRATUS DECK EXPANDING TOWARDS THE
FORECAST AREA FROM THE SOUTHEAST. SHORT RANGE MODEL GUIDANCE
ADVECTING DEEPER MOISTURE INTO THE REGION THROUGH THE MORNING AS
LOW LEVEL FLOW VEERS TO A S/SE DIRECTION. AT THE SAME TIME...BOTH
THE RAP AND NAM APPEAR TO BE OVERDOING MOISTURE ON THE 925/950 MB
LEVELS VERSUS THE LEADING EDGE OF THE CURRENT STRATUS DECK AS OF
07Z. CONFIDENCE IS GROWING IN LOWER CLOUDS REACHING THE SOUTHEASTERN
PORTIONS OF THE FORECAST AREA OVER THE NEXT FEW HOURS...AND POSSIBLY
GETTING AS FAR NORTH AS I-70 OVER THE EASTERN HALF OF CENTRAL
INDIANA AFTER DAYBREAK. WILL INCREASE CLOUD COVERAGE GRIDS SOUTHEAST
OF THE INDY METRO FOR THE MORNING AND MONITOR FOR ANY ADDITIONAL
UPDATES OVER THE NEXT FEW HOURS.
ELSEWHERE ACROSS CENTRAL INDIANA...MID AND HIGH LEVEL CLOUDS WILL
CONTINUE TO MOVE ACROSS THE REGION IN ADVANCE OF LOW PRESSURE
TRACKING THROUGH THE CENTRAL PLAINS. EXPECT AN INCREASE IN SURFACE
WINDS BY THIS AFTERNOON AS THE LOW APPROACHES...WITH SUSTAINEDS TO
NEAR 15MPH BY LATE DAY.
TEMPS...EVENTUAL EXTENT OF STRATUS DECK BOTH IN COVERAGE AND TIME
WILL BE CRITICAL...AS THEY WERE ON MONDAY...ON DETERMINING HOW WARM
TEMPS GO OVER THE SOUTHEASTERN PORTIONS OF THE FORECAST AREA. WITH
WARM ADVECTION TODAY...LOW LEVEL THERMALS SUPPORTIVE OF MAX TEMPS IN
THE LOWER/MIDDLE 50S. GENERALLY NEAR MAVMOS GUIDANCE...ALTHOUGH DID
UNDERCUT MAV BY A FEW DEGREES OVER SOUTHERN COUNTIES WITH POTENTIAL
IMPACTS FROM CLOUDS.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
ISSUED AT 336 AM EDT TUE MAR 18 2014
FORECAST CHALLENGES FOCUS ON PRECIP CHANCES TONIGHT/WEDNESDAY AND
AGAIN THURSDAY NIGHT WITH TWO SYSTEMS IMPACTING THE REGION.
LOW PRESSURE WILL PINWHEEL INTO THE GREAT LAKES WEDNESDAY AND SWING
A COLD FRONT ACROSS CENTRAL INDIANA DURING THE MORNING. MOISTURE
FETCH IS LIMITED OVERALL BUT FORCING THROUGH THE BOUNDARY LAYER AND
DIFFLUENCE ALOFT SHOULD BE MORE THAN SUFFICIENT FOR PRECIP TO
DEVELOP LATE TONIGHT INTO WEDNESDAY MORNING. STRENGTHENING LOW LEVEL
JET WILL ROTATE ACROSS CENTRAL INDIANA LATE TONIGHT AND PROMOTE A
BRIEF PERIOD WITH ISENTROPIC LIFT AHEAD OF THE FRONT AS WELL. WILL
CARRY LIKELY POPS OVER NORTHERN COUNTIES LATE TONIGHT AND WEDNESDAY
MORNING IN CLOSEST PROXIMITY TO BETTER FORCING AND DEEPER MOISTURE
WITH CHANCE POPS FURTHER SOUTH ACROSS THE FORECAST AREA. POTENTIAL
EXISTS FOR A CONVECTIVE COMPONENT TO PRECIP AND POTENTIALLY A FEW
RUMBLES OF THUNDER OVER THE NORTHERN WABASH VALLEY AS SOME ELEVATED
INSTABILITY WILL BE PRESENT.
BIG ISSUE WITH THE PASSAGE OF THE COLD FRONT WILL BE THE WINDS. THE
LOW LEVEL JET MOVING ACROSS THE REGION LATE TONIGHT WILL PROMOTE
GUSTS INCREASING TO 20-30MPH...BUT PRESENCE OF A BOUNDARY LAYER
INVERSION SHOULD LIMIT WHAT MAKES IT TO THE GROUND. AS COLD
ADVECTION TAKES HOLD ONCE THE FRONT GOES BY WEDNESDAY MORNING
HOWEVER...MODEL SOUNDINGS SHOW AN ENVIRONMENT CONDUCIVE FOR STRONGER
WINDS ALOFT BEING PULLED TO THE SURFACE AS STEEPENING LAPSE RATES
PROMOTE EXCELLENT LOW LEVEL MIXING. MAX GUSTS OF 35-40 MPH LIKELY
DURING THE AFTERNOON...AND MAY APPROACH WIND ADVISORY CRITERIA AS
WELL. WILL MAINTAIN LOW CHANCE POPS THROUGH THE AFTERNOON WITH
SUBTLE INSTABILITY PRESENT.
ANY PRECIP CHANCES WILL END BY WEDNESDAY NIGHT AS THE LOW LIFTS OUT
TO THE NORTHEAST AND IS REPLACED BY A SURFACE RIDGE. EXPECT DRY
CONDITIONS TO PERSIST INTO THURSDAY EVENING AS THE RIDGE PASSES
THROUGH THE OHIO VALLEY. A WARM FRONT WILL MOVE INTO THE REGION
THURSDAY NIGHT AIDED BY A 30-40KT LOW LEVEL JET. NICE AXIS OF LOW
LEVEL CONVERGENCE AND ISENTROPIC LIFT DEVELOPING AT THE NOSE OF THE
JET ACROSS THE NORTHERN HALF OF THE FORECAST AREA WILL SUPPORT SOME
RAIN SHOWER DEVELOPMENT ALONG THE WARM FRONT. MOST OF THE PRECIP
SHOULD MOVE NORTH OF THE FORECAST AREA WITH THE BOUNDARY BY 12Z
FRIDAY.
TEMPS...HIGHS EXPECTED BY MIDDAY WEDNESDAY WITH SLOWLY FALLING TEMPS
THEREAFTER WITHIN THE COLD ADVECTION. PREFERRED COLDER MAVMOS HIGHS.
MAVMOS WAS ALSO PREFERRED FOR THURSDAY AS TEMPS EXPECTED TO RECOVER
NICELY INTO THE 50S WITH WARM ADVECTION DEVELOPING IN ADVANCE OF THE
WARM FRONT LATE DAY. MOS GUIDANCE APPEARED REASONABLE FOR LOWS
THROUGHOUT THE PERIOD.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
ISSUED AT 310 AM EDT TUE MAR 18 2014
MODELS CONTINUE TO SUGGEST A PROGRESSIVE PATTERN DURING THE LONG
TERM PORTION OF THE FORECAST...WITH A LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT FRIDAY INTO FRIDAY NIGHT...AND ANOTHER ONE
EARLY NEXT WEEK.
FIRST SYSTEM FRIDAY INTO FRIDAY NIGHT MAY BRING A FEW
THUNDERSTORMS AS K INDICES AS HIGH AS 30 PLUS INDICATE A HEALTHY
PREFRONTAL INSTABILITY AXIS FRIDAY EVENING. EARLY NEXT WEEK SYSTEM
IS MUCH MORE BORDERLINE TEMPERATURE WISE...AND WILL CARRY RAIN OR
SNOW FOR NOW.
TEMPERATURES WILL BEGIN QUITE WARM IN THE STRONG WARM ADVECTION
AHEAD OF THE FRONT...BEFORE BECOMING NEAR TO BELOW NORMAL OVER THE
WEEKEND. NEAR TO JUST BEYOND THE SEVEN DAY FORECAST
PERIOD...GUIDANCE SUGGESTS POTENTIAL FOR YET ANOTHER COLD
INTRUSION FROM THE WINTER THAT REFUSES TO END.
&&
.AVIATION /DISCUSSION FOR THE 18/18Z TAF ISSUANCE/...
ISSUED AT 1257 PM EDT TUE MAR 18 2014
MVFR CEILINGS WITH SCATTERED SHOWERS LATE TONIGHT AND WEDNESDAY
MORNING. ALSO MVFR CEILINGS POSSIBLE AT START OF FORECAST PERIOD.
VFR REST OF THE TIME.
STRONG LOW PRESSURE OVER NORTHEAST KANSAS WILL MOVE TO NORTHEAST
ILLINOIS LATE TONIGHT AND NORTHERN LOWER MICHIGAN BY THE END OF THE
FORECAST PERIOD. A COLD FRONT WILL MOVE ACROSS OUR REGION EARLY
WEDNESDAY MORNING.
STRATUS CURRENTLY OVER SOUTHERN SECTIONS SHOULD BEGIN TO SCATTER OUT
NEXT FEW HOURS WITH DAYTIME MIXING. THUS BECOMING VFR MOST AREAS
UNTIL MIDNIGHT. SCATTERED SHOWERS WILL INCREASE ACROSS THE REGION
ESPECIALLY LATE TONIGHT. COULD BE AN ISOLATED THUNDERSHOWER NEAR
KLAF LATE TONIGHT...BUT CHANCES TOO LOW TO MENTION IN TAFS.
BIGGER ISSUE WILL BE THE DEVELOPMENT OF CEILINGS NEAR OR SLIGHTLY
ABOVE 3 THOUSAND FEET BY LATE EVENING AND WITH CEILINGS LOWERING TO
2 THOUSAND FEET LATE TONIGHT AND EARLY WEDNESDAY. SOME IMPROVEMENT
WILL OCCUR BY LATE WEDNESDAY MORNING AS DRIER AND COOLER AIR SPREADS
INTO OUR REGION.
SOUTHEAST WINDS UP TO 12 KNOTS WITH GUSTS TO 20 KNOTS WILL BE THE
RULE. WINDS MAY LESSEN SLIGHTLY THIS EVENING AND THEN INCREASE AGAIN
LATE TONIGHT AND WEDNESDAY. WEST WINDS WITH GUSTS UP TO 30 KNOTS
ARE POSSIBLE AFTER COLD FRONTAL PASSAGE BY LATE WEDNESDAY MORNING.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN/JAS
SHORT TERM...RYAN
LONG TERM...NIELD
AVIATION...JH
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
500 PM MDT TUE MAR 18 2014
.UPDATE...
ISSUED AT 455 PM MDT TUE MAR 18 2014
MAIN CONCERNS CONTINUE TO BE COMBINATION OF SNOW AND STRONG WINDS
ONGOING ACROSS THE AREA. HEAVY/BLOWING SNOW CAUSING SOME LOW
VISIBILITIES IN SEVERAL AREAS...WILL CONTINUE TO INCLUDE THIS IN
CURRENT HIGH WIND WARNING PER COORDINATION EARLIER TODAY AND NOT
ISSUE ANY ADDITIONAL WINTER HIGHLIGHTS ATTM. WHILE WINDS HAVE BEEN
SLOW TO RISE AND VERY SPORADIC...STARTING TO SEE A LOT OF
CONVECTIVE TYPE SHOWERS DEVELOPING BEHIND MAIN BAND OF
PRECIPITATION. THIS IS SUPPORTED BY NEAR TERM MODELED SOUNDINGS
INDICATING WEAK SFC BASED INSTABILITY THROUGH THE NEXT FEW HOURS.
WITH STRONG WINDS JUST OFF THE SFC IN THIS AREA...EXPECT STRONG
WINDS TO ACCOMPANY SOME OF THESE SHOWERS AS OPPOSED TO A MORE
WIDESPREAD STRONG WIND TYPE EVENT.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 230 PM MDT TUE MAR 18 2014
LATE THIS AFTERNOON THROUGH TONIGHT...AT 19Z UPPER LOW CENTERED ON
TOP OF GOODLAND WITH STRONGEST SFC WIND GUSTS GENERALLY WEST OF A
LINE FROM FLAGLER TO KIT CARSON WHERE GUSTS IN OUR PART OF THE AREA
APPROACHING 50 MPH WHILE JUST OUTSIDE OF IT GUSTS AROUND 60 MPH
BEING REPORTED.
FOR THE REST OF THE AFTERNOON AND TONIGHT UPPER LOW FORECAST TO MOVE
EAST REACHING NORTH CENTRAL KANSAS AROUND 00Z THEN WEAKENING A BIT
AS IT MOVES FURTHER EAST AND AWAY FROM THE AREA. STRONGEST SFC WINDS
AND GUSTS STILL EXPECTED TO SLOWLY MOVE EAST BEHIND THE UPPER LOW SO
NO CHANGES TO HIGH WIND WARNING. 18Z RUC SHOWS 850-800MB WINDS
ACTUALLY INCREASING ON THE BACKSIDE VERY LATE THIS AFTERNOON THROUGH
MIDNIGHT. NOT SURE HOW MUCH WILL MIX DOWN AFTER SUNSET OUT EAST
WHICH IS WHERE STRONGEST WINDS FORECAST SO FOR NOW WIND ADVISORY
WILL CONTINUE.
NORTHEAST TO SOUTHWEST ELONGATED BAND OF SNOW...MODERATE TO HEAVY AT
TIMES...CONTINUES TO SLOWLY MOVE SOUTHEAST. AM EXPECTING THE WORST
CONDITIONS PRESENTLY IN EASTERN COLORADO TO MOVE INTO NORTHWEST
KANSAS AND SOUTHWEST NEBRASKA (MAINLY NORTH OF THE INTERSTATE) BY
23Z CONTINUING EAST AND INCREASING COVERAGE ACROSS THE EASTERN 1/3
OF THE AREA DURING THE EVENING HOURS BEFORE EXITING THE AREA AROUND
MIDNIGHT. THE COMBINATION OF SNOW AND WIND WILL CREATE AREAS OF
BLOWING AND DRIFTING SNOW WITH REDUCED VISIBILITIES.
UNDER QUICKLY CLEARING SKIES LOWS TONIGHT IN THE LOW TO MID 20S
(WEST TO EAST).
WEDNESDAY...CLOUDINESS INCREASES A BIT AS A WEAK WEATHER DISTURBANCE
MOVES THROUGH. NO PRECIPITATION EXPECTED BUT COULD SEE NORTHWEST
WINDS GUST 20-25 MPH...MAINLY ACROSS THE NORTHEAST AND EASTERN PARTS
OF THE AREA. HIGH TEMPERATURES GENERALLY LOW 50S TO NEAR 60 (WEST TO
EAST).
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 206 PM MDT TUE MAR 18 2014
THURSDAY-FRIDAY...SHORTWAVE RIDGE WILL BE IN PLACE OVER THE
NORTHERN PLAINS WITH THE NEXT SHORTWAVE TROUGH UPSTREAM OVER THE
NORTHERN ROCKIES. RESULT WILL BE INCREASING SOUTHERLY FLOW ALOFT
AND WARMING TEMPERATURES ACROSS THE PLAINS THURSDAY. MUCH WARMER
TEMPERATURES EXPECTED THURSDAY WITH HIGHS AROUND 70 ACROSS MUCH OF
THE CWA. COLD FRONT MOVES THROUGH THE REGION LATE THURSDAY NIGHT
WITH HIGHS CLOSER TO SEASONAL NORMALS IN THE 50S. AS THIS FRONT
MOVES ACROSS THE REGION WE COULD SEE A PERIOD OF BREEZY
WINDS...HOWEVER GUSTS WILL REMAIN BELOW ADVISORY CRITERIA.
SATURDAY-TUESDAY...NORTHWEST FLOW WILL REMAIN IN PLACE ACROSS THE
NORTHERN PLAINS WHICH WILL ALLOW A SERIES OF WEAK DISTURBANCES TO
PASS NEAR OR NORTH OF OF OUR CWA AND SEND REINFORCING SHOTS OF
COOLER TEMPS INTO THE PLAINS. THESE QUICK MOVING FEATURES ARE ON
LESS THAN IDEAL TRACKS WITH LIMITED MOISTURE RETURN AND THERE IS
QUITE A BIT OF SPREAD BETWEEN GUIDANCE RUN-RUN ON EVOLUTION OF
THESE WEAK DISTURBANCES. BEST MODEL OVERLAP SEEMS TO BE ON PRECIP
CHANCES SATURDAY...HOWEVER THIS WOULD STILL BE FAIRLY LIGHT AND IN
THIS PATTERN/THIS RANGE I WAS NOT CONFIDENT ENOUGH TO RAISE POPS.
TEMPS SHOULD START OUT BELOW NORMAL SATURDAY (40S) BEFORE SEASONAL
TEMPS RETURN SUNDAY AND MONDAY (50S). BY NEXT MONDAY NIGHT/TUESDAY
THERE IS SOME INDICATION OF ANOTHER COLD FRONT DROPPING SOUTH OVER
THE CWA BRINGING BELOW NORMAL TEMPS BACK TO THE REGION AND POSSIBLY
INCREASING PRECIP CHANCES. NOT A LOT OF CONFIDENCE IN THESE LATER
PERIODS CONSIDERING THE MODEL SPREAD/LACK OF CONTINUITY...SO
DECIDED AGAINST MAKING MAJOR CHANGES TO CONSENSUS BLEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1100 AM MDT TUE MAR 18 2014
KGLD...MVFR CIGS AT TAF ISSUANCE WILL OCCASIONALLY FALL INTO IFR
RANGE BETWEEN 20Z AND 05Z AS WRAPAROUND SNOWFALL...WIND GUSTS TO
50KTS AND REDUCED VISIBILITIES MOVE IN FROM THE NORTH/NORTHWEST.
AFTER 06Z CONDITIONS ARE EXPECTED TO QUICKLY IMPROVE TO VFR WITH
NORTHWEST WINDS GENERALLY 10-12KTS THROUGH THE REST OF THE TAF
PERIOD. ONLY MID AND HIGH CLOUDS EXPECTED AFTER 06Z.
KMCK...MVFR/IFR CIGS AT TAF ISSUANCE WILL CONTINUE THROUGH 02Z IN
SNOW...WIND GUSTS TO 45KTS AND REDUCED VISIBILITIES AS AN UPPER
LEVEL LOW MOVES INTO THE AREA. AFTER 02Z VFR CONDITIONS EXPECTED
TO RETURN AS THE SYSTEM MOVES EAST AND AWAY FROM THE AREA.
NORTHWEST WINDS 10-12KTS EXPECTED AFTER 04Z OR SO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001>003-013>015-027>029-041-042.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ004-016.
CO...HIGH WIND WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ090>092.
NE...HIGH WIND WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
NEZ079>081.
&&
$$
UPDATE...JRM
SHORT TERM...99
LONG TERM...DR
AVIATION...99
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
350 PM CDT Tue Mar 18 2014
...Updated for long term discussion...
.SHORT TERM...(This evening through Wednesday)
ISSUED AT 206 PM CDT TUE MAR 18 2014
Models this morning are in good agreement with moving the upper
level trough east into central Kansas early this evening. The
better upper level dynamics will also begin to shift east as a
secondary surface boundary surges south across western Kansas
late this afternoon. As this boundary moves across southwest
Kansas, northwest winds of 30 to 40 mph will continue as low
level moisture increases. Given the timing of the exiting upper
level trough and increasing low level moisture will retain small
precipitation chances across north central Kansas early this
evening. Further south will keep an increase in clouds early this
evening but will not mention precipitation chances at this time.
Wind speeds across southeast Colorado earlier this afternoon have
on occasion approached high wind warning criteria. Visibilities
where these stronger winds were reported have been lowered to one
mile or less due to blowing dust. 12z NAM and 17z RAP indicated
the tightest surface pressure gradient along with the strongest
925mb to 850mb winds between 21z Tuesday and 00z Wednesday will be
near the Colorado border with the mean mixdown winds suggesting
sustained winds of near high wind warning criteria. Based on that
the models continue to suggest winds will be near High wind
warning criteria late today in far southwest Kansas and the 18z
wind speeds/gusts across southeast Colorado will continue the high
wind warning west of highway 83. Will also mention visibility
issues due to blowing dust. Further east will keep the wind
advisory going until 02z.
Surface ridge axis will then begin to build across western Kansas
towards 06z as the upper level trough moves from eastern Kansas
into Missouri. Given the cloud cover overnight along with wind
speeds of 10 to 15 mph the previous forecast still looks on track
with lows mainly in the mid to upper 20s
Westerly downslope flow will improve across western Kansas on
Wednesday with 925mb temperatures warmer around 6c from 00z
Wednesday to 00z Thursday. 850mb temperature trends over the same
time frame be +3c to +5c. Based on this warming trend and mostly
sunny conditions the highs mid week should easily rebound to near
60 degrees for much of western Kansas.
.LONG TERM...(Wednesday night through Tuesday)
ISSUED AT 343 PM CDT TUE MAR 18 2014
Lee troughing will develop Thursday ahead of the next upper level
system entering the northern Rockies, leading to south winds and warmer
temperatures. After this system traverses the northern plains on
Friday, a cold front will pass through western Kansas in its wake,
leading to falling high temperatures into the 60s Friday and 50s
Saturday. As the cool air gets deeper by Saturday night, mid level
isentropic lift may result in some light rain or light snow,
especially over far southwestern Kansas. Temperatures Sunday will
still be seasonably cool, with highs in the lower 50s.
A slight warming trend can be expected Sunday (highs in the upper
50s to lower 60s) as a weak lee trough develops ahead of the next
upper level trough. This system will push yet another cold front
through western Kansas by later Monday, with a return of cooler than
average high and low temperatures by Monday night and Tuesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1200 PM CDT TUE MAR 18 2014
Gusty northwest winds at 26kts to near 35 knots can be expected
through the remainder of the day across western Kansas. The
stronger winds are currently expected to occur at GCK and DDC
between 20z Tuesday and 01z Wednesday as a secondary surface
boundary moves across western Kansas. An area of low VFR or high
MVFR ceilings can also be expected for several hours late
today/early tonight behind this surface boundary given the latest
RAP and HRRR. Visibilities will briefly be reduced at times from
blowing dust. A few sprinkles or a brief shower will be possible
with the MVFR ceilings around 00z, mainly in the HYS area.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 27 60 32 71 / 10 0 0 0
GCK 24 60 32 70 / 10 0 0 0
EHA 26 59 32 72 / 0 0 0 0
LBL 25 61 32 72 / 10 0 0 0
HYS 28 59 30 70 / 30 0 0 0
P28 32 62 33 72 / 10 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 9 PM CDT this evening FOR KSZ030-031-044>046-
064>066-077>081-087>090.
HIGH WIND WARNING until 9 PM CDT /8 PM MDT/ this evening FOR
KSZ043-061>063-074>076-084>086.
&&
$$
SHORT TERM...Burgert
LONG TERM...Finch
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS GOODLAND KS
230 PM MDT TUE MAR 18 2014
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 230 PM MDT TUE MAR 18 2014
LATE THIS AFTERNOON THROUGH TONIGHT...AT 19Z UPPER LOW CENTERED ON
TOP OF GOODLAND WITH STRONGEST SFC WIND GUSTS GENERALLY WEST OF A
LINE FROM FLAGLER TO KIT CARSON WHERE GUSTS IN OUR PART OF THE AREA
APPROACHING 50 MPH WHILE JUST OUTSIDE OF IT GUSTS AROUND 60 MPH
BEING REPORTED.
FOR THE REST OF THE AFTERNOON AND TONIGHT UPPER LOW FORECAST TO MOVE
EAST REACHING NORTH CENTRAL KANSAS AROUND 00Z THEN WEAKENING A BIT
AS IT MOVES FURTHER EAST AND AWAY FROM THE AREA. STRONGEST SFC WINDS
AND GUSTS STILL EXPECTED TO SLOWLY MOVE EAST BEHIND THE UPPER LOW SO
NO CHANGES TO HIGH WIND WARNING. 18Z RUC SHOWS 850-800MB WINDS
ACTUALLY INCREASING ON THE BACKSIDE VERY LATE THIS AFTERNOON THROUGH
MIDNIGHT. NOT SURE HOW MUCH WILL MIX DOWN AFTER SUNSET OUT EAST
WHICH IS WHERE STRONGEST WINDS FORECAST SO FOR NOW WIND ADVISORY
WILL CONTINUE.
NORTHEAST TO SOUTHWEST ELONGATED BAND OF SNOW...MODERATE TO HEAVY AT
TIMES...CONTINUES TO SLOWLY MOVE SOUTHEAST. AM EXPECTING THE WORST
CONDITIONS PRESENTLY IN EASTERN COLORADO TO MOVE INTO NORTHWEST
KANSAS AND SOUTHWEST NEBRASKA (MAINLY NORTH OF THE INTERSTATE) BY
23Z CONTINUING EAST AND INCREASING COVERAGE ACROSS THE EASTERN 1/3
OF THE AREA DURING THE EVENING HOURS BEFORE EXITING THE AREA AROUND
MIDNIGHT. THE COMBINATION OF SNOW AND WIND WILL CREATE AREAS OF
BLOWING AND DRIFTING SNOW WITH REDUCED VISIBILITIES.
UNDER QUICKLY CLEARING SKIES LOWS TONIGHT IN THE LOW TO MID 20S
(WEST TO EAST).
WEDNESDAY...CLOUDINESS INCREASES A BIT AS A WEAK WEATHER DISTURBANCE
MOVES THROUGH. NO PRECIPITATION EXPECTED BUT COULD SEE NORTHWEST
WINDS GUST 20-25 MPH...MAINLY ACROSS THE NORTHEAST AND EASTERN PARTS
OF THE AREA. HIGH TEMPERATURES GENERALLY LOW 50S TO NEAR 60 (WEST TO
EAST).
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 206 PM MDT TUE MAR 18 2014
THURSDAY-FRIDAY...SHORTWAVE RIDGE WILL BE IN PLACE OVER THE
NORTHERN PLAINS WITH THE NEXT SHORTWAVE TROUGH UPSTREAM OVER THE
NORTHERN ROCKIES. RESULT WILL BE INCREASING SOUTHERLY FLOW ALOFT
AND WARMING TEMPERATURES ACROSS THE PLAINS THURSDAY. MUCH WARMER
TEMPERATURES EXPECTED THURSDAY WITH HIGHS AROUND 70 ACROSS MUCH OF
THE CWA. COLD FRONT MOVES THROUGH THE REGION LATE THURSDAY NIGHT
WITH HIGHS CLOSER TO SEASONAL NORMALS IN THE 50S. AS THIS FRONT
MOVES ACROSS THE REGION WE COULD SEE A PERIOD OF BREEZY
WINDS...HOWEVER GUSTS WILL REMAIN BELOW ADVISORY CRITERIA.
SATURDAY-TUESDAY...NORTHWEST FLOW WILL REMAIN IN PLACE ACROSS THE
NORTHERN PLAINS WHICH WILL ALLOW A SERIES OF WEAK DISTURBANCES TO
PASS NEAR OR NORTH OF OF OUR CWA AND SEND REINFORCING SHOTS OF
COOLER TEMPS INTO THE PLAINS. THESE QUICK MOVING FEATURES ARE ON
LESS THAN IDEAL TRACKS WITH LIMITED MOISTURE RETURN AND THERE IS
QUITE A BIT OF SPREAD BETWEEN GUIDANCE RUN-RUN ON EVOLUTION OF
THESE WEAK DISTURBANCES. BEST MODEL OVERLAP SEEMS TO BE ON PRECIP
CHANCES SATURDAY...HOWEVER THIS WOULD STILL BE FAIRLY LIGHT AND IN
THIS PATTERN/THIS RANGE I WAS NOT CONFIDENT ENOUGH TO RAISE POPS.
TEMPS SHOULD START OUT BELOW NORMAL SATURDAY (40S) BEFORE SEASONAL
TEMPS RETURN SUNDAY AND MONDAY (50S). BY NEXT MONDAY NIGHT/TUESDAY
THERE IS SOME INDICATION OF ANOTHER COLD FRONT DROPPING SOUTH OVER
THE CWA BRINGING BELOW NORMAL TEMPS BACK TO THE REGION AND POSSIBLY
INCREASING PRECIP CHANCES. NOT A LOT OF CONFIDENCE IN THESE LATER
PERIODS CONSIDERING THE MODEL SPREAD/LACK OF CONTINUITY...SO
DECIDED AGAINST MAKING MAJOR CHANGES TO CONSENSUS BLEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1100 AM MDT TUE MAR 18 2014
KGLD...MVFR CIGS AT TAF ISSUANCE WILL OCCASIONALLY FALL INTO IFR
RANGE BETWEEN 20Z AND 05Z AS WRAPAROUND SNOWFALL...WIND GUSTS TO
50KTS AND REDUCED VISIBILITIES MOVE IN FROM THE NORTH/NORTHWEST.
AFTER 06Z CONDITIONS ARE EXPECTED TO QUICKLY IMPROVE TO VFR WITH
NORTHWEST WINDS GENERALLY 10-12KTS THROUGH THE REST OF THE TAF
PERIOD. ONLY MID AND HIGH CLOUDS EXPECTED AFTER 06Z.
KMCK...MVFR/IFR CIGS AT TAF ISSUANCE WILL CONTINUE THROUGH 02Z IN
SNOW...WIND GUSTS TO 45KTS AND REDUCED VISIBILITIES AS AN UPPER
LEVEL LOW MOVES INTO THE AREA. AFTER 02Z VFR CONDITIONS EXPECTED
TO RETURN AS THE SYSTEM MOVES EAST AND AWAY FROM THE AREA.
NORTHWEST WINDS 10-12KTS EXPECTED AFTER 04Z OR SO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001>003-013>015-027>029-041-042.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ004-016.
CO...HIGH WIND WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ090>092.
NE...HIGH WIND WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
NEZ079>081.
&&
$$
SHORT TERM...99
LONG TERM...DR
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
207 PM MDT TUE MAR 18 2014
.UPDATE...
ISSUED AT 1215 PM MDT TUE MAR 18 2014
UPDATE SENT TO REFLECT CURRENT CONDITIONS AND FORECAST CONDITIONS
OVER THE NEXT 12 HOURS. RUC HANDLING THINGS WELL IN NEARLY EVERY
REGARD SO RELIED ON IT PRETTY HEAVILY.
AT 18Z UPPER LOW WAS CENTERED OVER THE WESTERN PORTION OF THE TRI-
STATE AREA. RUC FORECASTS THE LOW TO MOVE EAST TOWARD NORTON BY
21Z THEN INTO NORTH CENTRAL KANSAS/SOUTH CENTRAL NEBRASKA BY 00Z
AND FINALLY THE OMAHA AREA BY 03Z.
ON THE BACKSIDE OF THE LOW WILL BE INCREASING CHANCES FOR
SNOW...MODERATE TO POSSIBLY HEAVY AT TIMES ALONG WITH VISIBILITIES
BELOW ONE MILE AT TIMES...POSSIBLY EVEN LOWER.
AS FOR THE WIND...WITH THE UPPER LOW OVERHEAD THE STRONGEST WINDS
REMAIN JUST WEST OF THE FORECAST AREA WHICH IS MUCH FURTHER SOUTH
AND WEST THEN YESTERDAYS MODELS HAVE...THUS A DELAY IN THE ONSET
OF STRONGEST WINDS. KLIC NOW GUSTING 55KTS (63 MPH). AS THE UPPER
LOW SLOWLY MOVES EAST STRONGER WINDS WILL MOVE IN AND STILL
EXPECTING HIGH WIND WARNING CRITERIA WINDS TO BE MET.
WILL HAVE TO WATCH THREAT FOR BLIZZARD CONDITIONS. AT PRESENT TIME
THREAT LOOKS TO BE LIMITED TO AREAS GENERALLY ALONG AND WEST OF A
LINE FROM TRENTON NEBRASKA TO BURLINGTON COLORADO.
SNOWFALL TOTALS OF 1 TO 3 INCHES POSSIBLE...HIGHEST ALONG AND
NORTH OF INTERSTATE 70.
UPDATE ISSUED AT 930 AM MDT TUE MAR 18 2014
WEATHER CONDITIONS WILL QUICKLY DETERIORATE IN THE NEXT SEVERAL
HOURS AS A POTENT STORM SYSTEM IMPACTS THE AREA.
TEMPERATURES ARE FALLING NEAR OR BELOW FREEZING ACROSS THE
NORTHWEST PORTION OF THE AREA AND THIS COLDER AIRMASS WILL
CONTINUE TO SPREAD SOUTHEAST THROUGH THE REST OF THE DAY. RAIN IS
PREDOMINANT WEATHER TYPE FOR SOUTHEAST QUARTER OF THE AREA WITH
INCREASING CHANCES FOR PREDOMINANTLY SNOW AS ONE TRAVELS
NORTHWEST.
LIGHT ACCUMULATIONS ARE POSSIBLE WITH PERHAPS 3 INCHES OR SO. THE
PROBLEM IS THAT THE SNOW AND WIND WITH GUSTS TO 60 MPH WILL CREATE
SHARPLY REDUCED VISIBILITIES AND COULD FLIRT AT TIMES WITH
APPROACHING 1/4 MILE WHICH WOULD CREATE BLIZZARD CONDITIONS.
AT PRESENT TIME WILL HOLD OFF ON ANY CHANGES TO CURRENT HIGHLITES
BUT WILL MENTION THE THREAT FOR REDUCED VISIBILITIES IN THE
STATEMENT FOR NOW.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 341 AM MDT TUE MAR 18 2014
LATEST UPPER AIR ANALYSIS AND IR SATELLITE SHOW A LONG WAVE TROUGH
OVER THE ROCKIES WITH A SHORT WAVE TROUGH OVER EASTERN WYOMING. ON
THE WEST AND NORTH SIDE OF THE TROUGH A LARGE AREA OF CLOUD COVER
HAS ACCOMPANIED THE TROUGH TO THE SOUTHEAST. AT THE SURFACE LIGHT
SNOW WITH WIND GUSTS NEAR 60 MPH HAVE BEEN REPORTED OVER WYOMING
BEHIND THE UPPER LEVEL TROUGH. A SECONDARY COLD FRONT WAS LOCATED
OVER NORTHERN NEBRASKA EXTENDING WEST THROUGH CENTRAL WYOMING.
CLOSER TO HOME THE MAIN COLD FRONT THAT HAD MOVED THROUGH DURING THE
EVENING WAS NOW THROUGH THE WESTERN THIRD OF KANSAS AND ALMOST
HALFWAY THROUGH NEBRASKA.
TODAY NORTHWEST WINDS WILL STRENGTHEN THROUGH THE MORNING AHEAD OF
THE SECONDARY COLD FRONT. THE SECONDARY FRONT WILL MOVE THROUGH
THE AREA DURING THE MID TO LATE MORNING AHEAD OF THE UPPER LEVEL
SHORT WAVE TROUGH THAT WILL MOVE OVER THE AREA BY EARLY AFTERNOON.
BEHIND THE FRONT NORTHERLY WINDS WILL QUICKLY INCREASE. WIND GUSTS
AROUND 60 MPH WILL DEVELOP FROM WEST TO EAST DURING THE LATE
MORNING THROUGH THE AFTERNOON ON THE BACKSIDE OF THE SHORT WAVE
TROUGH. MODELS SHOW GRAHAM AND NORTON COUNTIES REMAINING EAST OF
THE HIGH WIND GUSTS. HOWEVER WIND GUSTS AROUND 50 MPH CAN BE
EXPECTED...ESPECIALLY TOWARD LATE AFTERNOON AS THE LOW LEVEL JET
STRENGTHENS BEHIND THE EXITING UPPER LEVEL TROUGH. DURING THE
EARLY EVENING THE WINDS WILL QUICKLY DECLINE AS THE TEMPERATURES
COOL PREVENTING THE STRONGER WINDS ABOVE THE SURFACE FROM MIXING
DOWN.
IN ADDITION TO THE WIND...MID LEVEL LIFT IN THE 600-800MB LAYER WILL
DEVELOP BEHIND THE MID LEVEL LOW. SOUNDINGS SHOW A SMALL LAYER OF
CONVECTIVE INSTABILITY FROM 800-700MB AS WELL. AS THE MID LEVEL
LIFT MOVES OVER THE AREA SOUNDINGS OVER THE NORTHERN HALF OF THE
AREA SATURATE TO THE GROUND. THIS ADDS CONFIDENCE THAT ANY PRECIP.
THAT DEVELOPS WILL MAKE IT TO THE GROUND SO HAVE INCREASED PRECIP.
CHANCES NORTH OF HIGHWAY 24 AS A RESULT. WET BULB ZERO HEIGHTS
INDICATE THE PRECIP. OVER THE NORTHERN HALF OF THE AREA WILL BE
MOSTLY SNOW...WITH THE PRECIP. TRANSITIONING TO RAIN TO THE SOUTH.
THE PRECIP. WILL COME TO AN END FROM WEST TO EAST DURING THE LATE
AFTERNOON AND EARLY EVENING AS LIFT ON THE BACKSIDE OF THE MID LEVEL
TROUGH MOVES EAST OF THE AREA. BY THE EVENING ANTICIPATE 2 INCHES
OF SNOWFALL ALONG/NORTH OF THE KS/NE LINE...WITH LESSER AMOUNTS TO
THE SOUTH.
VISIBILITY RESTRICTIONS FROM BLOWING SNOW WILL BE A CONCERN
TODAY...ESPECIALLY FOR LOCATIONS NORTH OF HIGHWAY 24 WHERE
SNOWFALL WILL BE MORE LIKELY. SINCE A HIGH WIND WARNING IS ALREADY
OUT...WILL MENTION THE REDUCED VISIBILITY IN THE WARNING. WOULD
NOT BE SURPRISED IF VISIBILITIES DROPPED TO UNDER A MILE AT TIMES
IN LOCATIONS WITH HEAVIER SNOWFALL RATES...WHICH IS CERTAINLY
POSSIBLE GIVEN THE CONVECTIVE POTENTIAL OF THE ENVIRONMENT TODAY.
HOWEVER WOULD EXPECT VISIBILITIES TO PREDOMINANTLY BE IN THE 2-4
MILE RANGE OVER THE NORTHERN HALF OF THE AREA.
BLOWING DUST WILL ALSO REDUCE VISIBILITIES FOR THE ENTIRE AREA
DURING THE LATE MORNING THROUGH THE AFTERNOON. ANTICIPATE THE
THREAT OF BLOWING DUST TO DECLINE DURING THE AFTERNOON NORTH OF
HIGHWAY 24 SINCE ANY SNOWFALL SHOULD HELP SETTLE THE DUST SINCE THE
GROUND TEMPERATURES ARE ABOVE FREEZING. DURING THE AFTERNOON WILL
CONTINUE THE MENTION OF BLOWING DUST SINCE THIS AREA IS LESS FAVORED
FOR PRECIP. ON A SIDE NOTE HAVE INVESTIGATED THE AIR QUALITY FORECAST
FOR THE TRI-STATE AREA. THE MODEL SHOWS THE MAJORITY OF THE
BLOWING DUST OCCURRING SOUTHEAST OF THE AREA. ONLY GUESS FOR WHY IS
THE MODEL THINKS THE PRECIP. WILL LIMIT THE EFFECT OF BLOWING DUST
OVER THE SOUTHERN PART OF THE AREA...EVEN THOUGH THE BETTER
CHANCES ARE FURTHER NORTH.
TONIGHT WINDS WILL DECLINE...BECOMING LIGHT ACROSS THE ENTIRE AREA
AFTER MIDNIGHT. THERE MAY BE SOME BLOWING DUST IN THE EARLY EVENING
BEFORE WINDS BECOME LIGHT. DECIDED TO EXTEND THE HIGH WIND WARNING
AND WIND ADVISORY UNTIL 2Z SINCE MODELS SHOW THE COLD AIR ADVECTION
ALLOWING WIND GUSTS OF 45 TO 50 MPH TO MIX TO THE GROUND. LATER
SHIFTS CAN CANCEL THE HAZARD EARLY OR END IT IN SECTIONS IF
NEEDED.
WEDNESDAY THE LONG WAVE TROUGH AXIS MOVES ACROSS THE AREA WITH AN
UPPER LEVEL RIDGE MOVING IN BEHIND IT. DRIER...WARMER AIR WILL
ACCOMPANY THE UPPER LEVEL RIDGE OVER THE AREA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 206 PM MDT TUE MAR 18 2014
THURSDAY-FRIDAY...SHORTWAVE RIDGE WILL BE IN PLACE OVER THE
NORTHERN PLAINS WITH THE NEXT SHORTWAVE TROUGH UPSTREAM OVER THE
NORTHERN ROCKIES. RESULT WILL BE INCREASING SOUTHERLY FLOW ALOFT
AND WARMING TEMPERATURES ACROSS THE PLAINS THURSDAY. MUCH WARMER
TEMPERATURES EXPECTED THURSDAY WITH HIGHS AROUND 70 ACROSS MUCH OF
THE CWA. COLD FRONT MOVES THROUGH THE REGION LATE THURSDAY NIGHT
WITH HIGHS CLOSER TO SEASONAL NORMALS IN THE 50S. AS THIS FRONT
MOVES ACROSS THE REGION WE COULD SEE A PERIOD OF BREEZY
WINDS...HOWEVER GUSTS WILL REMAIN BELOW ADVISORY CRITERIA.
SATURDAY-TUESDAY...NORTHWEST FLOW WILL REMAIN IN PLACE ACROSS THE
NORTHERN PLAINS WHICH WILL ALLOW A SERIES OF WEAK DISTURBANCES TO
PASS NEAR OR NORTH OF OF OUR CWA AND SEND REINFORCING SHOTS OF
COOLER TEMPS INTO THE PLAINS. THESE QUICK MOVING FEATURES ARE ON
LESS THAN IDEAL TRACKS WITH LIMITED MOISTURE RETURN AND THERE IS
QUITE A BIT OF SPREAD BETWEEN GUIDANCE RUN-RUN ON EVOLUTION OF
THESE WEAK DISTURBANCES. BEST MODEL OVERLAP SEEMS TO BE ON PRECIP
CHANCES SATURDAY...HOWEVER THIS WOULD STILL BE FAIRLY LIGHT AND IN
THIS PATTERN/THIS RANGE I WAS NOT CONFIDENT ENOUGH TO RAISE POPS.
TEMPS SHOULD START OUT BELOW NORMAL SATURDAY (40S) BEFORE SEASONAL
TEMPS RETURN SUNDAY AND MONDAY (50S). BY NEXT MONDAY NIGHT/TUESDAY
THERE IS SOME INDICATION OF ANOTHER COLD FRONT DROPPING SOUTH OVER
THE CWA BRINGING BELOW NORMAL TEMPS BACK TO THE REGION AND POSSIBLY
INCREASING PRECIP CHANCES. NOT A LOT OF CONFIDENCE IN THESE LATER
PERIODS CONSIDERING THE MODEL SPREAD/LACK OF CONTINUITY...SO
DECIDED AGAINST MAKING MAJOR CHANGES TO CONSENSUS BLEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1100 AM MDT TUE MAR 18 2014
KGLD...MVFR CIGS AT TAF ISSUANCE WILL OCCASIONALLY FALL INTO IFR
RANGE BETWEEN 20Z AND 05Z AS WRAPAROUND SNOWFALL...WIND GUSTS TO
50KTS AND REDUCED VISIBILITIES MOVE IN FROM THE NORTH/NORTHWEST.
AFTER 06Z CONDITIONS ARE EXPECTED TO QUICKLY IMPROVE TO VFR WITH
NORTHWEST WINDS GENERALLY 10-12KTS THROUGH THE REST OF THE TAF
PERIOD. ONLY MID AND HIGH CLOUDS EXPECTED AFTER 06Z.
KMCK...MVFR/IFR CIGS AT TAF ISSUANCE WILL CONTINUE THROUGH 02Z IN
SNOW...WIND GUSTS TO 45KTS AND REDUCED VISIBILITIES AS AN UPPER
LEVEL LOW MOVES INTO THE AREA. AFTER 02Z VFR CONDITIONS EXPECTED
TO RETURN AS THE SYSTEM MOVES EAST AND AWAY FROM THE AREA.
NORTHWEST WINDS 10-12KTS EXPECTED AFTER 04Z OR SO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001>003-013>015-027>029-041-042.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ004-016.
CO...HIGH WIND WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ090>092.
NE...HIGH WIND WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
NEZ079>081.
&&
$$
UPDATE...99
SHORT TERM...JTL
LONG TERM...DR
AVIATION...99
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
209 PM CDT Tue Mar 18 2014
...Updated short term discussion...
.SHORT TERM...(This evening through Wednesday)
ISSUED AT 206 PM CDT TUE MAR 18 2014
Models this morning are in good agreement with moving the upper
level trough east into central Kansas early this evening. The
better upper level dynamics will also begin to shift east as a
secondary surface boundary surges south across western Kansas
late this afternoon. As this boundary moves across southwest
Kansas, northwest winds of 30 to 40 mph will continue as low
level moisture increases. Given the timing of the exiting upper
level trough and increasing low level moisture will retain small
precipitation chances across north central Kansas early this
evening. Further south will keep an increase in clouds early this
evening but will not mention precipitation chances at this time.
Wind speeds across southeast Colorado earlier this afternoon have
on occasion approached high wind warning criteria. Visibilities
where these stronger winds were reported have been lowered to one
mile or less due to blowing dust. 12z NAM and 17z RAP indicated
the tightest surface pressure gradient along with the strongest
925mb to 850mb winds between 21z Tuesday and 00z Wednesday will be
near the Colorado border with the mean mixdown winds suggesting
sustained winds of near high wind warning criteria. Based on that
the models continue to suggest winds will be near High wind
warning criteria late today in far southwest Kansas and the 18z
wind speeds/gusts across southeast Colorado will continue the high
wind warning west of highway 83. Will also mention visibility
issues due to blowing dust. Further east will keep the wind
advisory going until 02z.
Surface ridge axis will then begin to build across western Kansas
towards 06z as the upper level trough moves from eastern Kansas
into Missouri. Given the cloud cover overnight along with wind
speeds of 10 to 15 mph the previous forecast still looks on track
with lows mainly in the mid to upper 20s
Westerly downslope flow will improve across western Kansas on
Wednesday with 925mb temperatures warmer around 6c from 00z
Wednesday to 00z Thursday. 850mb temperature trends over the same
time frame be +3c to +5c. Based on this warming trend and mostly
sunny conditions the highs mid week should easily rebound to near
60 degrees for much of western Kansas.
.LONG TERM...(Wednesday through Monday)
ISSUED AT 305 AM CDT TUE MAR 18 2014
Zonal west/east flow will generally be found above the Central
Plains throughout the extended period with a few weak shortwaves
moving through the Northern Plains. The first weak shortwave is
PROGGED to move through western Canada Thursday then through the
Northern Plains Thursday night into Friday. As this feature
approaches, surface lee troughing will develop shifting westerly
winds on Wednesday to the south southwest Wednesday night into
Thursday. 850 mb temperatures rebound into the single digits
Wednesday then teens on Thursday. This should bring increasing
temperatures with highs in the lower 60s Wednesday and lower 70s
Thursday. Mostly clear skies are anticipated Wednesday into Thursday
with only a few high clouds observed. A cold front is then progged
to move through the area Thursday night into Friday as the
aforementioned shortwave moves into the Northern Plains. This will
shift winds to more of a northerly direction Thursday night into
Friday, then to the northeast Friday night. No precipitation is
expected with this cold front with only a slight increase in mid to
upper level clouds. Slightly cooler temperatures are expected on
Friday with highs ranging from the mid 50s across west central
Kansas to lower 60s across the KS/CO border. Lows Thursday through
Saturday morning will generally be in the 30s.
Models then suggest the next upper level shortwave to move through
the Northern Plains Saturday, then into the Great Lakes region
Sunday. This will help push an arctic high down into the Northern
Plains. Easterly winds will be observed across western Kansas
Saturday into Saturday night. This will bring easterly upslope flow
to western Kansas allowing low to mid level clouds to increase.
Winds then shift to the southeast on Sunday as the high treks slowly
to the southeast. A slight chance of showers will be possible
Saturday night into Sunday, otherwise expect mostly cloudy skies.
Cooler temperatures are expected Saturday and Sunday with highs
around 50 degrees with lows in the lower 30s.
Another upper level shortwave may move through the Northern Plains
Monday. This feature could help push another cold front through the
area shifting winds back to the north. No precipitation is expected
Monday at this time with partly cloudy skies. Temperatures warm
slightly on Monday with highs in the lower 60s then cool back down
to the 50s behind the aforementioned front Tuesday. Lows will
continue to dip into the 30s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1200 PM CDT TUE MAR 18 2014
Gusty northwest winds at 26kts to near 35 knots can be expected
through the remainder of the day across western Kansas. The
stronger winds are currently expected to occur at GCK and DDC
between 20z Tuesday and 01z Wednesday as a secondary surface
boundary moves across western Kansas. An area of low VFR or high
MVFR ceilings can also be expected for several hours late
today/early tonight behind this surface boundary given the latest
RAP and HRRR. Visibilities will briefly be reduced at times from
blowing dust. A few sprinkles or a brief shower will be possible
with the MVFR ceilings around 00z, mainly in the HYS area.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 27 62 35 72 / 0 0 0 0
GCK 24 61 33 71 / 0 0 0 0
EHA 24 61 35 73 / 0 0 0 0
LBL 25 62 34 74 / 0 0 0 0
HYS 27 61 33 71 / 20 0 0 0
P28 31 63 37 74 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 9 PM CDT this evening FOR KSZ030-031-044>046-
064>066-077>081-087>090.
HIGH WIND WARNING until 9 PM CDT /8 PM MDT/ this evening FOR
KSZ043-061>063-074>076-084>086.
&&
$$
SHORT TERM...Burgert
LONG TERM...Hovorka_42
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1215 PM MDT TUE MAR 18 2014
.UPDATE...
ISSUED AT 1215 PM MDT TUE MAR 18 2014
UPDATE SENT TO REFLECT CURRENT CONDITIONS AND FORECAST CONDITIONS
OVER THE NEXT 12 HOURS. RUC HANDLING THINGS WELL IN NEARLY EVERY
REGARD SO RELIED ON IT PRETTY HEAVILY.
AT 18Z UPPER LOW WAS CENTERED OVER THE WESTERN PORTION OF THE TRI-
STATE AREA. RUC FORECASTS THE LOW TO MOVE EAST TOWARD NORTON BY
21Z THEN INTO NORTH CENTRAL KANSAS/SOUTH CENTRAL NEBRASKA BY 00Z
AND FINALLY THE OMAHA AREA BY 03Z.
ON THE BACKSIDE OF THE LOW WILL BE INCREASING CHANCES FOR
SNOW...MODERATE TO POSSIBLY HEAVY AT TIMES ALONG WITH VISIBILITIES
BELOW ONE MILE AT TIMES...POSSIBLY EVEN LOWER.
AS FOR THE WIND...WITH THE UPPER LOW OVERHEAD THE STRONGEST WINDS
REMAIN JUST WEST OF THE FORECAST AREA WHICH IS MUCH FURTHER SOUTH
AND WEST THEN YESTERDAYS MODELS HAVE...THUS A DELAY IN THE ONSET
OF STRONGEST WINDS. KLIC NOW GUSTING 55KTS (63 MPH). AS THE UPPER
LOW SLOWLY MOVES EAST STRONGER WINDS WILL MOVE IN AND STILL
EXPECTING HIGH WIND WARNING CRITERIA WINDS TO BE MET.
WILL HAVE TO WATCH THREAT FOR BLIZZARD CONDITIONS. AT PRESENT TIME
THREAT LOOKS TO BE LIMITED TO AREAS GENERALLY ALONG AND WEST OF A
LINE FROM TRENTON NEBRASKA TO BURLINGTON COLORADO.
SNOWFALL TOTALS OF 1 TO 3 INCHES POSSIBLE...HIGHEST ALONG AND
NORTH OF INTERSTATE 70.
UPDATE ISSUED AT 930 AM MDT TUE MAR 18 2014
WEATHER CONDITIONS WILL QUICKLY DETERIORATE IN THE NEXT SEVERAL
HOURS AS A POTENT STORM SYSTEM IMPACTS THE AREA.
TEMPERATURES ARE FALLING NEAR OR BELOW FREEZING ACROSS THE
NORTHWEST PORTION OF THE AREA AND THIS COLDER AIRMASS WILL
CONTINUE TO SPREAD SOUTHEAST THROUGH THE REST OF THE DAY. RAIN IS
PREDOMINANT WEATHER TYPE FOR SOUTHEAST QUARTER OF THE AREA WITH
INCREASING CHANCES FOR PREDOMINANTLY SNOW AS ONE TRAVELS
NORTHWEST.
LIGHT ACCUMULATIONS ARE POSSIBLE WITH PERHAPS 3 INCHES OR SO. THE
PROBLEM IS THAT THE SNOW AND WIND WITH GUSTS TO 60 MPH WILL CREATE
SHARPLY REDUCED VISIBILITIES AND COULD FLIRT AT TIMES WITH
APPROACHING 1/4 MILE WHICH WOULD CREATE BLIZZARD CONDITIONS.
AT PRESENT TIME WILL HOLD OFF ON ANY CHANGES TO CURRENT HIGHLITES
BUT WILL MENTION THE THREAT FOR REDUCED VISIBILITIES IN THE
STATEMENT FOR NOW.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 341 AM MDT TUE MAR 18 2014
LATEST UPPER AIR ANALYSIS AND IR SATELLITE SHOW A LONG WAVE TROUGH
OVER THE ROCKIES WITH A SHORT WAVE TROUGH OVER EASTERN WYOMING. ON
THE WEST AND NORTH SIDE OF THE TROUGH A LARGE AREA OF CLOUD COVER
HAS ACCOMPANIED THE TROUGH TO THE SOUTHEAST. AT THE SURFACE LIGHT
SNOW WITH WIND GUSTS NEAR 60 MPH HAVE BEEN REPORTED OVER WYOMING
BEHIND THE UPPER LEVEL TROUGH. A SECONDARY COLD FRONT WAS LOCATED
OVER NORTHERN NEBRASKA EXTENDING WEST THROUGH CENTRAL WYOMING.
CLOSER TO HOME THE MAIN COLD FRONT THAT HAD MOVED THROUGH DURING THE
EVENING WAS NOW THROUGH THE WESTERN THIRD OF KANSAS AND ALMOST
HALFWAY THROUGH NEBRASKA.
TODAY NORTHWEST WINDS WILL STRENGTHEN THROUGH THE MORNING AHEAD OF
THE SECONDARY COLD FRONT. THE SECONDARY FRONT WILL MOVE THROUGH
THE AREA DURING THE MID TO LATE MORNING AHEAD OF THE UPPER LEVEL
SHORT WAVE TROUGH THAT WILL MOVE OVER THE AREA BY EARLY AFTERNOON.
BEHIND THE FRONT NORTHERLY WINDS WILL QUICKLY INCREASE. WIND GUSTS
AROUND 60 MPH WILL DEVELOP FROM WEST TO EAST DURING THE LATE
MORNING THROUGH THE AFTERNOON ON THE BACKSIDE OF THE SHORT WAVE
TROUGH. MODELS SHOW GRAHAM AND NORTON COUNTIES REMAINING EAST OF
THE HIGH WIND GUSTS. HOWEVER WIND GUSTS AROUND 50 MPH CAN BE
EXPECTED...ESPECIALLY TOWARD LATE AFTERNOON AS THE LOW LEVEL JET
STRENGTHENS BEHIND THE EXITING UPPER LEVEL TROUGH. DURING THE
EARLY EVENING THE WINDS WILL QUICKLY DECLINE AS THE TEMPERATURES
COOL PREVENTING THE STRONGER WINDS ABOVE THE SURFACE FROM MIXING
DOWN.
IN ADDITION TO THE WIND...MID LEVEL LIFT IN THE 600-800MB LAYER WILL
DEVELOP BEHIND THE MID LEVEL LOW. SOUNDINGS SHOW A SMALL LAYER OF
CONVECTIVE INSTABILITY FROM 800-700MB AS WELL. AS THE MID LEVEL
LIFT MOVES OVER THE AREA SOUNDINGS OVER THE NORTHERN HALF OF THE
AREA SATURATE TO THE GROUND. THIS ADDS CONFIDENCE THAT ANY PRECIP.
THAT DEVELOPS WILL MAKE IT TO THE GROUND SO HAVE INCREASED PRECIP.
CHANCES NORTH OF HIGHWAY 24 AS A RESULT. WET BULB ZERO HEIGHTS
INDICATE THE PRECIP. OVER THE NORTHERN HALF OF THE AREA WILL BE
MOSTLY SNOW...WITH THE PRECIP. TRANSITIONING TO RAIN TO THE SOUTH.
THE PRECIP. WILL COME TO AN END FROM WEST TO EAST DURING THE LATE
AFTERNOON AND EARLY EVENING AS LIFT ON THE BACKSIDE OF THE MID LEVEL
TROUGH MOVES EAST OF THE AREA. BY THE EVENING ANTICIPATE 2 INCHES
OF SNOWFALL ALONG/NORTH OF THE KS/NE LINE...WITH LESSER AMOUNTS TO
THE SOUTH.
VISIBILITY RESTRICTIONS FROM BLOWING SNOW WILL BE A CONCERN
TODAY...ESPECIALLY FOR LOCATIONS NORTH OF HIGHWAY 24 WHERE
SNOWFALL WILL BE MORE LIKELY. SINCE A HIGH WIND WARNING IS ALREADY
OUT...WILL MENTION THE REDUCED VISIBILITY IN THE WARNING. WOULD
NOT BE SURPRISED IF VISIBILITIES DROPPED TO UNDER A MILE AT TIMES
IN LOCATIONS WITH HEAVIER SNOWFALL RATES...WHICH IS CERTAINLY
POSSIBLE GIVEN THE CONVECTIVE POTENTIAL OF THE ENVIRONMENT TODAY.
HOWEVER WOULD EXPECT VISIBILITIES TO PREDOMINANTLY BE IN THE 2-4
MILE RANGE OVER THE NORTHERN HALF OF THE AREA.
BLOWING DUST WILL ALSO REDUCE VISIBILITIES FOR THE ENTIRE AREA
DURING THE LATE MORNING THROUGH THE AFTERNOON. ANTICIPATE THE
THREAT OF BLOWING DUST TO DECLINE DURING THE AFTERNOON NORTH OF
HIGHWAY 24 SINCE ANY SNOWFALL SHOULD HELP SETTLE THE DUST SINCE THE
GROUND TEMPERATURES ARE ABOVE FREEZING. DURING THE AFTERNOON WILL
CONTINUE THE MENTION OF BLOWING DUST SINCE THIS AREA IS LESS FAVORED
FOR PRECIP. ON A SIDE NOTE HAVE INVESTIGATED THE AIR QUALITY FORECAST
FOR THE TRI-STATE AREA. THE MODEL SHOWS THE MAJORITY OF THE
BLOWING DUST OCCURRING SOUTHEAST OF THE AREA. ONLY GUESS FOR WHY IS
THE MODEL THINKS THE PRECIP. WILL LIMIT THE EFFECT OF BLOWING DUST
OVER THE SOUTHERN PART OF THE AREA...EVEN THOUGH THE BETTER
CHANCES ARE FURTHER NORTH.
TONIGHT WINDS WILL DECLINE...BECOMING LIGHT ACROSS THE ENTIRE AREA
AFTER MIDNIGHT. THERE MAY BE SOME BLOWING DUST IN THE EARLY EVENING
BEFORE WINDS BECOME LIGHT. DECIDED TO EXTEND THE HIGH WIND WARNING
AND WIND ADVISORY UNTIL 2Z SINCE MODELS SHOW THE COLD AIR ADVECTION
ALLOWING WIND GUSTS OF 45 TO 50 MPH TO MIX TO THE GROUND. LATER
SHIFTS CAN CANCEL THE HAZARD EARLY OR END IT IN SECTIONS IF
NEEDED.
WEDNESDAY THE LONG WAVE TROUGH AXIS MOVES ACROSS THE AREA WITH AN
UPPER LEVEL RIDGE MOVING IN BEHIND IT. DRIER...WARMER AIR WILL ACCOMPANY
THE UPPER LEVEL RIDGE OVER THE AREA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 341 AM MDT TUE MAR 18 2014
DRY AND MILD FOR THE REST OF THE WORK WEEK...BECOMING COOLER WITH A
CHANCE FOR PRECIP OVER THE WEEKEND. SYNOPTIC PATTERN BEGINS WITH
SHORTWAVE RIDGING EVOLVING INTO NORTHWESTERLY/ZONAL FLOW. GEM/ECMWF
DEPICT A SHORTWAVE TROUGH MOVING FROM THE PAC NW ACROSS THE COLORADO
ROCKIES FRIDAY INTO SATURDAY...BUT WITH ALMOST NO SUPPORT FROM THE
18Z AND 00Z GFS/GEFS DO BELIEVE THERE IS SOME UNCERTAINTY TO PRECIP
SAT INTO SUN...ESPECIALLY SINCE IN THE BEST CASE SCENARIO FOR
PRECIP AMOUNTS WILL BE LIGHT. TOWARDS THE END OF THE WEEKEND AND
INTO NEXT WEEK A RIDGE BUILDS ACROSS THE WESTERN CONUS...WHICH WILL
EVENTUALLY MOVE EAST BRINGING A RETURN TO WARMER WEATHER.
THURSDAY THROUGH FRIDAY...SUNNY AND DRY. RH VALUES ON THURSDAY WILL
BE AROUND 10 PERCENT...BUT WINDS SHOULD REMAIN LIGHT ENOUGH THAT
CRITICAL FIRE WEATHER CONDITIONS WILL NOT BE MET. HOWEVER...IT
APPEARS TONIGHTS GUIDANCE HAS COME IN WITH SLIGHTLY STRONGER WINDS
THAN YESTERDAY...AND THERE DOES APPEAR TO BE A VERY LOW CHANCE /BUT
A CHANCE NONETHELESS/ FOR FIRE WEATHER CONDITIONS TO BECOME
CRITICAL. FRIDAY A COLD FRONT MOVES THROUGH FROM NORTH TO SOUTH
BRINGING BREEZY WINDS AND A FEW CLOUDS...BUT NO CHANCE FOR PRECIP.
SATURDAY INTO EARLY SUNDAY...A WEAK SHORTWAVE TROUGH MOVING ACROSS
THE COLORADO ROCKIES AND INTO THE CENTRAL HIGH PLAINS AT THE SAME
TIME AS MID-LEVEL MOISTURE ADVECTS SOUTH THROUGH THE HIGH PLAINS.
THERE WILL BE A CHANCE FOR PRECIP SATURDAY INTO SATURDAY EVENING
ASSOCIATED WITH THIS LARGE-SCALE LIFT...BUT GIVEN LACK OF
INSTABILITY AND A DRY LAYER BELOW ABOUT 700MB ANY PRECIP THAT
DEVELOPS WILL HAVE A HARD TIME REACHING THE GROUND...AND WHILE JUST
WENT WITH STANDARD SLIGHT CHANCE OF RAIN/SNOW...WOULD NOT BE
SURPRISED IF IT ONLY ENDS UP BEING SPRINKLES/FLURRIES.
SUNDAY INTO MONDAY...DECREASING CLOUDS AND SOUTHERLY WINDS WILL LEAD
TO A MILD SUNDAY AND MONDAY AHEAD OF ANOTHER WEAK COLD FRONT LATE
MONDAY AFTERNOON. TIMING OF THIS FRONT MAY CHANGE SO THERE IS
GENERALLY LOWER THAN USUAL CONFIDENCE ON THE MONDAY HIGH TEMPS...BUT
IF THE FROPA CAN HOLD OFF UNTIL LATE AFTERNOON HIGHS WILL APPROACH 60.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1100 AM MDT TUE MAR 18 2014
KGLD...MVFR CIGS AT TAF ISSUANCE WILL OCCASIONALLY FALL INTO IFR
RANGE BETWEEN 20Z AND 05Z AS WRAPAROUND SNOWFALL...WIND GUSTS TO
50KTS AND REDUCED VISIBILITIES MOVE IN FROM THE NORTH/NORTHWEST.
AFTER 06Z CONDITIONS ARE EXPECTED TO QUICKLY IMPROVE TO VFR WITH
NORTHWEST WINDS GENERALLY 10-12KTS THROUGH THE REST OF THE TAF
PERIOD. ONLY MID AND HIGH CLOUDS EXPECTED AFTER 06Z.
KMCK...MVFR/IFR CIGS AT TAF ISSUANCE WILL CONTINUE THROUGH 02Z IN
SNOW...WIND GUSTS TO 45KTS AND REDUCED VISIBILITIES AS AN UPPER
LEVEL LOW MOVES INTO THE AREA. AFTER 02Z VFR CONDITIONS EXPECTED
TO RETURN AS THE SYSTEM MOVES EAST AND AWAY FROM THE AREA.
NORTHWEST WINDS 10-12KTS EXPECTED AFTER 04Z OR SO.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HIGH WIND WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
KSZ001>003-013>015-027>029-041-042.
WIND ADVISORY UNTIL 9 PM CDT THIS EVENING FOR KSZ004-016.
CO...HIGH WIND WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ090>092.
NE...HIGH WIND WARNING UNTIL 8 PM MDT /9 PM CDT/ THIS EVENING FOR
NEZ079>081.
&&
$$
UPDATE...99
SHORT TERM...JTL
LONG TERM...JJM
AVIATION...99
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
111 PM EDT TUE MAR 18 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 434 AM EDT TUE MAR 18 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WNW FLOW ALF OVER
THE UPR LKS BTWN PERSISTENT MEAN TROF OVER QUEBEC AND RDG ALONG THE
W COAST. A VIGOROUS SHRTWV THAT TOPPED THE WRN RDG IS MOVING ESEWD
THRU THE CENTRAL ROCKIES...ACCOMPANIED BY 12Z-24Z H3 HGT FALLS UP TO
300M IN WYOMING. THERE HAVE EVEN BEEN A FEW LTG STRIKES IN THE COMMA
HEAD OF THE ACCOMPANYING CLD SHIELD OVER THE NRN ROCKIES INTO THE
NRN PLAINS. BAND OF ENHANCED CLD TO THE NE OF DVLPG SFC LO PRES IN
NEBRASKA EXTENDS NE INTO CNTRL MN/NW WI...CORRELATED BEST WITH AXIS
OF HIER H7-6 FGEN...BUT WELL N OF H85 WARM FNT STRETCHING FM SDAKOTA
THRU NRN IOWA. PCPN HAS HAD A HARD TIME DEVELOPING UNDER THE SHARPER
FGEN DUE TO RATHER DRY NATURE OF THE 00Z MPX RAOB...BUT SOME SN HAS
REACHED AS FAR NE AS HYR IN NW WI AS OF 09Z. ALTHOUGH SKIES ARE CLDY
OVER UPR MI...THERE IS CURRENTLY NO PCPN FALLING OVER THE CWA
DESPITE LARGER SCALE WAD AND PRESENCE OF WEAKER H85 WARM FNT
ASSOCIATED WITH SHRTWV TRACKING ACRS NRN LK SUP IN WNW FLOW ALF.
FEED OF LLVL DRY AIR SHOWN ON THE 00Z GRB RAOB IS LIKELY PLAYING A
ROLE. EVEN DEEPER DRIER AIR IS PRESENT S OF GRB.
MAIN FCST CONCERNS THRU TNGT WL FOCUS ON POPS/SN AMOUNTS AND NEED
FOR HEADLINES AS SHRTWV/ACCOMPANYING SFC LO OVER THE ROCKIES/PLAINS
MOVE TO THE E.
TODAY...AS S WINDS TO THE E OF DEEPENING LO PRES IN THE PLAINS
STRENGTHEN...BAND OF SHARPER H7-6 FGEN IS FCST TO SHIFT TO THE NE
INTO UPR MI. MORE DYNAMIC SUPPORT WL COME FM UPR DVGC IN RRQ OF H3
JET MAX FCST TO BE MOVING NEWD THRU ONTARIO. SINCE NEGATIVE H85
DEWPT ADVECTION ASSOCIATED WITH THE DRY AIR TO THE S WL BE IMPACTING
MAINLY THE E HALF OF THE CWA...ACCOMPANYING POPS WL BE HIER OVER THE
W. BUT EVEN THERE...MOST OF THE MODELS SHOW SOME DRYING WL ARRIVE
AND SHUNT THE PCPN OFF INTO NW LK SUP AS AXIS OF FGEN SHIFTS TO THE
NW AS WELL. THE NAM IS MOST AGGRESSIVE WITH THIS DRYING. AS FAR AS
SN AMOUNTS ARE CONCERNED...AXIS OF H7 SPECIFIC HUMIDITY UP TO 3 G/KG
IS FCST TO BE OVER THE AXIS OF SHARPER FGEN THIS MRNG. BUT INFLUX OF
DRIER LLVL AIR IS FCST TO DIMINISH THIS VALUE THRU THE DAY.
OVERALL...SUSPECT SN AMOUNTS WL APRCH ADVY CRITERIA OVER THE FAR W
WHERE THE FGEN IS PROGGED TO BE MOST PERSISTENT AND DRYING LESS
AGGRESSIVE. NARROW...RATHER HI...NARROW DGZ RESULTING IN SN/WATER
RATIOS IN THE 10-15:1 RANGE WL NOT HELP SN TOTALS.
TNGT...SHRTWV FM THE PLAINS IS FCST TO BECOME MORE NEGATIVELY TILTED
AS IT MOVES INTO WI BY 12Z WED. ALTHOUGH DEEP LYR QVECTOR CNVGC IN
THE DVPA/PERSISTENT ISENTROPIC ASCENT AHEAD OF THIS FEATURE IS FCST
TO OVERSPREAD THE CWA...THE SHARPER FORCING AND ACCOMPANYING H4-2
DVGC ARE PROGGED TO IMPACT THE SE HALF OF THE CWA...WHERE THE DRIER
AIR IS FCST TO BE DEEPEST. OUT OF SYNC NATURE OF THE FORCING/DEEPER
MSTR IS OF CONCERN AND WL LIKELY LIMIT SN TOTALS. IN FACT...MODEL
QPF VARIES SGNFTLY ACRS THE CWA. ADVY SN IS MOST LIKELY OVER THE W
HALF WHERE MSTR IS DEEPER AND SHARPENING CYC NNE FLOW LATER TNGT
MIGHT ENHANCE SN TOTALS A BIT. SINCE THERE IS LTL INTERACTION WITH
THE ARCTIC BRANCH IN CANADA...ANOTHER FACTOR THAT WL LIMIT
QPF...MODELS HAVE TRENDED A BIT FARTHER S WITH THE SFC LO TRACK...
INDICATING THE SFC LO WL REACH NO FARTHER N THAN ABOUT MILWAUKEE BY
12Z WED. THESE TRENDS SUG THE BULK OF THE PCPN WL BE IN THE FORM OF
SN. RETAINED A MENTION OF -FZRA OVER THE SE PER THE WARMER NAM
MODEL...WHICH SHOWS ELEVATED WARM LYR CENTERED AT 3K FT THRU THE NGT
NEAR LK MI. LATER SHIFTS MAY BE ABLE TO REMOVE THIS MENTION OF MIXED
PCPN IF CURRENT TRENDS PERSIST.
AS FOR HEADLINES...OPTED TO ISSUE AN ADVY FOR THE W TODAY GIVEN AXIS
OF SHARPER FGEN/LATER DRYING. EXPANDED THE ADVYS TO THE E TO COVER
THE ENTIRE CWA BY LATE TNGT TO REFLECT ARRIVAL OF SHARPER DYNAMICS/
HIER POPS THAT WL INFLUENCE THE AREA INTO WED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 524 AM EDT TUE MAR 18 2014
STRONG SOUTHERN STREAM SYSTEM CROSSES THE GREAT LAKES TO START THE
DAY ON WEDNESDAY. MODELS ARE SETTLING ON A SFC LOW AROUND DAYBREAK
ON WEDNESDAY NEAR MILWAUKEE WI...TRACKING INTO THE NORTHERN PART OF
LK HURON BY WEDNESDAY EVENING. UPPER LEVELS BECOME NEGATIVE TILTED
LATE TONIGHT INTO WEDNESDAY...BUT WITHOUT MUCH ADDITIONAL INTERACTION
FROM NORTHERN BRANCH SHORTWAVES/COLD AIR...SYSTEM IS LOOKING MORE
PROGRESSIVE THAN IT DID 24 HR AGO. THIS SHOWS UP SEEING THE FARTHER
SOUTH AND EAST SFC LOW /GEM-NH HAS SHOWN THIS FOR MULTIPLE RUNS/.
WARM LAYER NOT VERY MUCH OF A FACTOR NOW EITHER...PERHAPS REACHING
INTO FAR SE CWA FOR A VERY BRIEF TIME LATE TONIGHT THROUGH AROUND
DAYBREAK ON WEDNESDAY. PROGRESSIVE NATURE OF SYSTEM IS VERY APPARENT
BY LOOKING AT H85-H7 MOISTURE TRANSPORT...WHICH IS NOW MAXIMIZING
LATE TONIGHT INTO WEDNESDAY OVER THE CNTRL GREAT LAKES INSTEAD OF
INTO CNTRL UPR MICHIGAN. THUS...NOT AS MUCH MOISTURE FOR THE SYSTEM
TO WORK WITH AND H7 MIXING RATIOS ONLY TOP OUT BTWN 2.25 AND 2.5G/KG
COMPARED TO THE 3.0 OR HIGHER VALUES SHOWN PREVIOUSLY. USING THE
GARCIA METHOD THIS WOULD SUGGEST UP TO 5 INCHES OF SNOW IN A 12 HOUR
PERIOD AND THIS ESTIMATE IS ON PAR WHEN USING AN AVERAGE OF MODEL
TOTAL QPF BTWN 00Z WED AND 00Z THURSDAY ALONG WITH SLR/S AROUND 12:1
/LIMITED LIFT OCCURRING IN THE HIGH DGZ WELL ABOVE H7/.
OVERALL SEEMS LIKE FAR WEST CWA WILL SEE THE MOST SNOW FROM THIS
SYSTEM BY WEDNESDAY EVENING AS H7 FGEN THAT IMPACTS THAT AREA TODAY
MAY PROVIDE A FOCUS FOR ADDITIONAL SNOW LATER TONIGHT THROUGH MUCH
OF WEDNESDAY AS LARGER SCALE FORCING FM MAIN SHORTWAVE IMPACTS THE
AREA AS SHOWN BY SWATH OF MODERATE H85-H7/H7-H5 Q-VECTOR CONVERGENCE
AND PERSISTENT DIVERGENCE ALOFT WITHIN RIGHT ENTRANCE OF H3 JET OVER
NORTHERN ONTARIO AND QUEBEC. ADDITIONALLY...THERE ARE INDICATIONS
THAT SNOW TIED TO FGEN AREA WOULD BE ENHANCED OVER THE NORTHWEST
CWA VCNTY OF KEWEENAW AS PRESENCE OF FS CONVERGENCE SUGGESTS THE
SNOW BAND WILL PIVOT OVER THAT AREA AS IT LIFTS NORTH THEN MOVES
EAST /RESULTING IN MODERATE SNOW POSSIBLY PERSISTING INTO EARLY
WEDNESDAY EVENING/. FARTHER TO THE EAST OVER THE REST OF THE CWA
IT GETS TRICKY TO FIGURE HOW MUCH SNOW MAY OCCUR...ESPECICALLY OVER
THE CNTRL AS THAT AREA WOULD BE ON THE EASTERN SUBSIDENCE SIDE OF
THE FGEN OVER THE WEST AND NORTHWEST CWA. H7 FGEN DOES INCREASE
ACROSS CNTRL AND EASTERN CWA ON WEDNESDAY AS THE LARGER SCALE
FORCING IMPACTS THE AREA BUT WITH THE MINIMAL MOISTURE ADVECTION
WORKING INTO THE SYSTEM...QPF/SNOW AMOUNTS DO NOT LOOK TO GET OUT OF
HAND. ADVY SNOW AMOUNTS SEEM REASONABLE LATER TONIGHT THROUGH
WEDNESDAY.
HEADLINES...AFTER COORD WITH SHORT TERM FORECASTER AND SURROUNDING
OFFICES DECIDED ON AN ADVY FOR ENTIRE CWA. GIVEN UNCERTAINTY ON
WHERE STRONGER FGEN SNOW BAND REDEVELOPS TONIGHT INTO WEDNESDAY WILL
LET LATER SHIFTS ASSESS WHETHER UPGRADE TO WARNING IS NEEDED FOR ANY
PARTS OF CWA. START TIMES FOR ADVY VARY WITH FAR WEST BEGINNING
TODAY AND REST OF CWA COMING INTO THE ADVY LATER THIS EVENING AND
OVERNIGHT TONIGHT. RAN THE ADVY THROUGH EARLY WEDNESDAY EVENING MOST
AREAS...BUT DID PUSH IT THROUGH MIDNIGHT WEDNESDAY NIGHT OVER
NORTHEAST CWA WITH SNOW LINGERING ON BACK SIDE OF THE LOW PRESSURE
AND ALSO WITH GUSTY NW WINDS LEADING TO BLSN CLOSER TO LK SUPERIOR.
THURSDAY AND THURSDAY NIGHT...COULD SEE LINGERING LIGHT SNOW SHOWERS
NEAR LK SUPERIOR ON THURSDAY IN WAKE OF THE SYSTEM. ECMWF/GFS INDICATE
MOISTURE THROUGH H9 WITH H9 TEMPS AROUND -10C. SLIGHT CHANCES WILL
COVER THIS POTENTIAL. HIGH PRESSURE RIDGE CROSSES THURSDAY NIGHT AND
DOES NOT APPEAR THAT MID-HIGH CLOUDS WILL ARRIVE AHEAD OF NEXT SYSTEM
UNTIL LATE THURSDAY NIGHT OVER THE WEST. TEMPS MAY DIVE TOWARD ZERO
OR EVEN BLO OVER INTERIOR SECTIONS WITH THE FRESH SNOW COVER AND CALM
CONDITIONS. NW WINDS BLO H9 MAY KEEP TEMPS SLIGHTLY WARMER NEAR LK
SUPERIOR.
REST OF EXTENDED...GFS STILL FARTHER NORTH COMPARED TO ECMWF AND
GEM-NH WITH SHORTWAVE/SFC TROUGH SLIDING ACROSS WESTERN GREAT LAKES
FRIDAY INTO FRIDAY EVENING. SLIGHT CHANCES FOR MOST AREAS...BUT HAVE
A BIT HIGHER ALONG WISCONSIN BORDER. COLD FRONT WORKS THROUGH LATER
FRIDAY NIGHT INTO SATURDAY AS NORTHERN STREAM WAVE DROPS THROUGH.
ENOUGH MID LEVEL MOISTURE TIED TO THE WAVE/COLD FRONT TO HAVE SOME
SMALLER CHANCES IN FOR MAINLY NORTH HALF OF CWA. WITH H85 TEMPS
DROPPING BLO -20C ON SATURDAY AND WITH LINGERING FORCING STILL
AROUND...LIKED PREVIOUS SHIFTS LIKELY POPS FOR NW AND NCNTRL CWA ON
SATURDAY FOR POTENTIAL OF LAKE ENHANCED SNOW SHOWERS. LARGE HIGH
PRESSURE BUILDS IN FOR SUNDAY LEADING TO DRY AND VERY CHILLY WEATHER.
HIGH TEMPS ON SUNDAY FORECAST TO BE IN THE TEENS TO MID 20S...WHICH
WOULD END UP CLOSE TO 20 DEGREES BLO NORMAL FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 110 PM EDT TUE MAR 18 2014
A BAND OF SN THAT BROUGHT IFR CONDITIONS TO THE TAF SITES THIS MRNG
WILL MOVE OUT THIS AFTERNOON WITH CONDITIONS IMPROVING TO MVFR. DRY
AIR WILL MOVE IN FROM THE SOUTH AND CAUSE MVFR CONDITIONS THROUGH
THE EVENING. AS LO PRES IN THE PLAINS MOVES TO THE E TNGT...MORE
WIDESPREAD SN WL ARRIVE AND LOWER CONDITIONS TO IFR/LIFR
AGAIN...MAINLY AT IWD AND CMX LATER TONIGHT AND THIS WILL LAST INTO
WED MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 524 AM EDT TUE MAR 18 2014
E-SE WINDS UP 20 KTS THIS MORNING WILL BACK TO THE N-NE AND INCREASE
TO UP TO 25-30 KTS BY WED AS A LO PRES IN THE PLAINS MOVES TO THE
LOWER GREAT LAKES. THE PASSAGE OF A HI PRES RIDGE/FLATTER PRES
GRADIENT IN ITS WAKE WILL RESULT IN DIMINISHING AND BACKING WINDS TO
THE S INTO FRI. AFTER ANOTHER LOW SHIFTS TO THE EAST THROUGH THE
LOWER GREAT LAKES ON FRI AND ANOTHER CANADIAN HIGH PRESSURE BUILDS
INTO THE NORTHERN PLAINS...A STRONGER N-NW WIND UP TO 25-30 KTS WILL
DEVELOP LATE FRI INTO SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 2 AM WEDNESDAY TO MIDNIGHT EDT
WEDNESDAY NIGHT FOR MIZ006-007-085.
WINTER WEATHER ADVISORY FROM 11 PM EDT /10 PM CDT/ THIS EVENING
TO 8 PM EDT /7 PM CDT/ WEDNESDAY FOR MIZ004-005-010-011-084.
WINTER WEATHER ADVISORY UNTIL 8 PM EDT /7 PM CDT/ WEDNESDAY FOR
MIZ001>003-009.
WINTER WEATHER ADVISORY FROM 2 AM EDT /1 AM CDT/ TO 8 PM EDT /7
PM CDT/ WEDNESDAY FOR MIZ012>014.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...07
MARINE...KC
AREA FORECAST DISCUSSION
NWS BILLINGS MT
307 PM MDT TUE MAR 18 2014
.SHORT TERM...VALID FOR WED AND THU...
SNOW SHOWERS WERE CROSSING THE FORECAST AREA THIS AFTERNOON PER
RADAR IMAGERY AND OBSERVATIONS. STILL EXPECTING POSSIBLE ISOLATED
THUNDER BASED ON RAP SOUNDINGS SHOWING CLOSE TO 200 J/KG OF CAPE
AND SSEO SHOWING DECENT PROBABILITIES OF STRONG RADAR ECHOES. HAVE
INCLUDED ISOLATED THUNDER THIS EVENING E OF KBIL. SCATTERED RAIN
AND SNOW SHOWERS WILL END FROM W TO E TONIGHT AS SHORTWAVE CROSSES
THE AREA. MIN TEMPERATURES IN THE 20S WERE IN GOOD SHAPE BASED ON
GUIDANCE...AND 850 MB TEMPERATURES A FEW DEGREES BELOW ZERO
DEGREES C.
WED WILL BE WARMER AND DRY AS WEAK UPPER RIDGING CROSSES THE AREA.
HAVE NUDGED UP HIGH TEMPERATURES SLIGHTLY BASED ON EXPECTED
MIXING. PACIFIC ENERGY WILL MOVE INTO THE REGION WED NIGHT AHEAD
OF ANOTHER SHORTWAVE. NOTED THAT LOW-LEVELS WERE FAIRLY DRY ON THE
MODELS...SO HAVE TRIMMED BACK THE EASTWARD EXTENT AND STRENGTH OF
POPS. AS A SURFACE LOW MOVES ACROSS THE MT/CANADIAN BORDER...WINDS
WILL INCREASE FROM KBIL W. PATTERN DID NOT LOOK SUPPORTIVE OF
ADVISORY CRITERIA WINDS IN THE GAP FLOW AREAS. DID RAISE LOW
TEMPERATURES IN RESPONSE TO THE WINDS AND CLOUD COVER.
THE SHORTWAVE WILL PUSH A PACIFIC COLD FRONT ACROSS THE AREA ON
THU. ENSEMBLE SITUATIONAL AWARENESS TABLE SHOWED WIND SPEED
ANOMALIES AT 850 MB SO IT WILL BE WINDY ACROSS THE AREA. AIRMASS
WILL MOISTEN THROUGH THE DAY SO HAD SLIGHT CHANCE POPS IN THE
MORNING AND CHANCE POPS IN THE AFTERNOON. HIGH TEMPERATURES WILL
RANGE FROM THE 30S W TO THE 40S E. A MUCH STRONGER COLD FRONT WAS
FORECAST TO PUSH S THROUGH THE AREA THU NIGHT AND THE BEST CHANCES
FOR PRECIPITATION LOOKED TO BE N AND E OF KBIL. WRF WAS SLOWER
THAN THE GFS IN BRINGING QPF S INTO THE AREA SO KEPT POPS AT
MAINLY CHANCE VALUES FOR NOW...WITH SOME LIKELIES IN THE EASTERN
ZONES. AMOUNT OF SNOW ACCUMULATION WAS A BIT UNCERTAIN FOR THU
NIGHT DUE TO THE MODEL QPF TIMING DIFFERENCES. WINDY CONDITIONS
WILL CONTINUE THU NIGHT. ARTHUR
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
MODELS CONTINUE IN PRETTY GOOD AGREEMENT THROUGH THE EXTENDED
PERIOD...FAVORING A CHILLY AND UNSETTLED PATTERN. BIGGEST CHANGES
WERE TO RAISE PRECIP CHANCES A BIT FRIDAY ACROSS THE ENTIRE REGION
AND TO RAISE PRECIP CHANCES A BIT LATE SUNDAY INTO MONDAY.
A STRONG SURGE OF COLD AIR MOVES IN FROM THE NE FRIDAY. SHORTWAVE
ENERGY MOVING ACROSS THE REGION AND NW FLOW IN THE MID LEVELS
WILL HELP ENHANCE THE POTENTIAL FOR SNOW. THE COLD AIR REMAINS
ENTRENCHED ACROSS THE REGION INTO SATURDAY AS MORE SHORTWAVE
ENERGY MOVES OVERHEAD...THUS THE POTENTIAL FOR SNOW SHOWERS
REMAINS. IT WILL BE CHILLY FRIDAY AND SATURDAY...WITH HIGHS IN THE
UPPER 20S TO MID 30S.
THE COLD AIR APPEARS TO RETREAT TO THE EAST A BIT SATURDAY NIGHT
INTO SUNDAY AHEAD OF ANOTHER SURGE OF COLD CANADIAN AIR THAT IS
PROGGED TO MOVE INTO THE REGION SUNDAY NIGHT...WITH MORE SHORTWAVE
ENERGY...AND UPPER LEVEL JET ENERGY. THUS...IT APPEARS THAT THE
POTENTIAL FOR SNOW AGAIN INCREASES LATE SUNDAY INTO MONDAY. YET
ANOTHER REINFORCING SHOT OF COLD AIR IS FORECAST TO IMPACT THE
REGION MONDAY NIGHT...WITH FAVORABLE MID/UPPER LEVEL DYNAMICS FOR
SNOW SHOWERS ACROSS THE REGION. HIGH TEMPS SUNDAY SHOULD REACH
THE MID 30S TO MID 40S...BEFORE COOLING OFF AGAIN MONDAY. STC
&&
.AVIATION...
A DISTURBANCE WILL CONTINUE TO BRING SCATTERED RAIN AND SNOW
SHOWERS TO THE REGION THROUGH THIS EVENING...WITH BRIEF MVFR/IFR
CONDITIONS POSSIBLE IN ANY SHOWER. ISOLATED THUNDERSTORMS ARE
ALSO POSSIBLE ACROSS WESTERN AND CENTRAL ROUTES INTO EARLY THIS
EVENING...INCLUDING NEAR KBIL AND KMLS. AREAS OF MOUNTAIN
OBSCURATION ARE LIKELY INTO THIS EVENING. MOSTLY VFR CONDITIONS
WILL PREVAIL FROM LATE THIS EVENING INTO WEDNESDAY...BUT SW WINDS
WILL AGAIN BECOME GUSTY IN THE KLVM TO 6S0 CORRIDOR. STC
&&
.PRELIMINARY POINT TEMP/POPS...
WED THU FRI SAT SUN MON TUE
-----------------------------------------------------------
BIL 026/050 033/043 023/032 016/035 023/043 023/037 023/035
30/B 13/W 35/J 33/J 12/J 43/J 33/J
LVM 021/044 028/038 018/029 010/034 019/043 022/034 021/043
20/N 24/W 33/J 32/J 13/J 42/J 33/J
HDN 024/049 031/044 024/033 014/035 022/043 022/039 022/038
30/B 14/W 45/J 32/J 12/J 43/J 32/J
MLS 028/050 032/045 025/032 015/032 021/041 022/037 019/035
30/B 04/W 55/J 21/E 12/J 32/J 22/J
4BQ 025/048 029/044 024/032 015/032 020/042 022/037 020/037
30/B 03/W 45/J 22/J 12/J 32/J 22/J
BHK 026/046 029/046 022/028 013/028 016/036 019/034 016/033
30/B 04/W 65/J 21/E 12/J 22/J 22/J
SHR 020/044 026/042 021/031 011/033 018/044 019/038 019/042
30/B 03/W 34/J 43/J 12/J 43/J 33/J
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
315 PM CDT TUE MAR 18 2014
.SHORT TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 315 PM CDT TUE MAR 18 2014
PCPN AMOUNTS AND PCPN TYPE TONIGHT ARE THE MAIN FORECAST CONCERNS IN
THIS PERIOD.
FAIRLY IMPRESSIVE SHORTWAVE TROUGH WILL CONTINUE TO MOVE THROUGH THE
CENTRAL PLAINS THE NEXT 18 HOURS. 120 KNOT 300 MB JET STREAK OVER
NEW MEXICO AT 12Z THIS MORNING WILL CONTINUE TO PUNCH EASTWARD. AREA
OF 500 MB HEIGHT FALLS (AROUND 100 METERS OVER SOUTHERN COLORADO
AND NORTHERN NEW MEXICO AT 12Z) WILL ALSO CONTINUE TO SHIFT EAST
ACROSS KANSAS AND OKLAHOMA.
MESOSCALE BAND OF MODERATE TO HEAVY SNOW THAT HAS BEEN TO OUR WEST
TODAY SHOULD MOVE INTO OUR WESTERN COUNTIES THIS EVENING...BUT THE
INTENSITY SHOULD DECREASE AS IT MOVES EAST. WE WERE ALREADY STARTING
TO SEE SIGNS OF THAT WITH REGIONAL RADAR LOOP AS OF 310 PM. HIGH
RESOLUTION RAP MODEL SUGGESTS ANOTHER (BUT WEAKER) BAND WILL
DEVELOP FARTHER EAST WITH A NEW AREA OF MID LEVEL FRONTOGENESIS...
AND THAT APPEARS REASONABLE. IN GENERAL...SLOWED DOWN THE ENDING
OF PCPN TONIGHT AND ALSO THE DECREASE IN CLOUD COVER. ACCUMULATING
SNOW SHOULD MAINLY BE LESS THAN AN INCH BUT PARTS OF KNOX AND
POSSIBLY ANTELOPE COUNTY MAY SEE A BIT MORE THAN THAT BEFORE 06Z.
MEASURABLE PCPN SHOULD END IN ALL OF THE FORECAST AREA BY 09Z.
BRISK NORTHWEST WINDS WILL OVERSPREAD THE AREA THIS EVENING BUT
DECREASE SOME LATER TONIGHT AS THE PRESSURE GRADIENT WEAKENS.
PREVIOUS FORECAST OF LOWS IN THE UPPER 20S AND LOWER 30S SEEMS ON
TRACK.
A WEAKER SHORTWAVE TROUGH IN THE NORTHWEST MID LEVEL FLOW WILL
AFFECT MAINLY THE DAKOTAS AND MINNESOTA ON WEDNESDAY...BUT KEPT SOME
LOW POPS GOING IN NORTHEAST NEBRASKA IN THE AFTERNOON. THE 12Z GFS
IS THE MOST BULLISH WITH PCPN AMOUNTS WEDNESDAY AND SEEMED A BIT
OVERDONE. FUTURE FORECASTS MAY HAVE TO ADD A CHANCE OF SHOWERS INTO
WEDNESDAY EVENING BUT LEFT THAT PERIOD DRY FOR NOW. EXPECT HIGHS 45
TO 50 NORTH AND 50 TO 55 SOUTH ON WEDNESDAY.
LEFT THE PERIOD FROM THURSDAY INTO FRIDAY DRY...WITH MAIN FORCING
EXPECTED TO STAY MOSTLY NORTH OF OUR AREA FRIDAY. HIGHS SHOULD BE
MOSTLY 60S THURSDAY AND MAINLY 50S FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 315 PM CDT TUE MAR 18 2014
THE REGION WILL REMAIN IN NORTHWEST FLOW ALOFT THROUGH THE ENTIRE
FORECAST PERIOD WITH MOSTLY DRY AND COOL CONDITIONS. A LARGE COLD
SFC HIGH PRESSURE AREA WILL DROP SOUTH ACROSS THE CENTRAL PLAINS
OVER THE WEEKEND. THIS WILL BRING 850MB TEMPS INTO THE -8C TO -14C
RANGE SUNDAY ACROSS THE FORECAST AREA WITH THE 12Z ECMWF BEING
SLIGHTLY COLDER THAN THE 12Z GFS. BRIEF RETURN FLOW IS EXPECTED
SUNDAY NIGHT INTO MONDAY AHEAD OF A POTENT SHORTWAVE TROUGH OVER THE
NORTHERN PLAINS. THIS FEATURE WILL MOVE SOUTHEAST ACROSS THE
NORTHERN PLAINS AND CLIP EASTERN NEBRASKA AND WESTERN IOWA. WILL
INCLUDE A SMALL POP IN OUR NORTHEAST ASSOCIATED WITH THIS WAVE.
COLDER AIR SPILLS IN BEHIND THIS FEATURE WITH -8C TO -18C 850MB
TEMPS ADVERTISED FOR NEXT TUESDAY.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1237 PM CDT TUE MAR 18 2014
DETERIORATING CONDITIONS FROM VFR TO MVFR EXPECTED LATE THIS AFTN
AS BAND OF PCPN MOVES IN FROM THE WEST. REGIONAL RADAR MOSAIC
SHOWING AREA OF -SN OVER MOST OF WRN NEB ON BACKSIDE OF SFC LOW
CURRENTLY CENTERED IN ERN KS. EXPECT ACTIVITY TO GRADUALLY SLIDE
EAST OVER THE NEXT SEVERAL HOURS AS THE SFC LOW LIFTS TWD THE
UPPER MIDWEST. PCPN AT TIMES MAY BE -RASN MIX. PCPN ACTIVITY
SHOULD BE COMING TO A CLOSE THEN SHORTLY AFT 06Z TONIGHT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...KERN
AVIATION...DEE
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1245 PM CDT TUE MAR 18 2014
.UPDATE...
ISSUED AT 1101 AM CDT TUE MAR 18 2014
SNOW CONTINUES TO STRUGGLE TO ACCUMULATE OUTSIDE OF HEAVIER
BANDS. HOWEVER IN THE HEAVY BANDS THE VISIBILITY FALLS BELOW ONE
MILE...AND AT TIMES NEAR ZERO...AND ACCUMULATION IS OCCURRING.
SNOWFALL RATES OF GREATER THAN 1 INCH AN HOUR IS ABLE TO OVERCOME
THE MELTING. AS THE BANDS CONTINUE TO MIGRATE LATE THIS MORNING
AND EARLY THIS AFTERNOON...LOCALLY AMOUNTS AROUND 6 INCHES ARE
LIKELY. TEMPS ARE CONTINUING TO FALL AND EXPECT THE SNOW AND
BLOWING SNOW TO NOW IMPACT CUSTER AND FRONTIER COUNTIES SO
EXPANDED THE WINTER WX ADV...REPLACING THE WIND ADVISORY. LATE
THIS AFTERNOON INTO THE EVENING AS THE SNOW DIMINISHES FROM NW TO
SE...ROAD CONDITIONS SHOULD IMPROVE QUICKLY AS THE SNOW MELTS
FROM HIGHER SUN ANGLE AND A WARM GROUND...REMEMBER IT WAS AROUND
70 YESTERDAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT TUE MAR 18 2014
THE MODELS APPEAR TO BE SHOWING A HIGH DEGREE OF UNPREDICTABILITY
WITH THE STORM BEARING DOWN ON WRN AND NCNTL NEB THIS MORNING.
SEVERAL HIGHWAYS INCLUDING PARTS OF I-90/I-80 IN WYOMING NEAR
SHERIDAN...CASPER...LARAMIE AND CHEYENNE ARE CLOSED AND THE NUMBER
OF CLOSURES HAS BEEN RAPIDLY INCREASING SINCE MIDNIGHT. THE RAP13
AND 06Z NAM ARE HAMMERING SCNTL NEB WITH TROWAL AND THE RAP40 SHOWS
STRONG PETTERSON FGEN AT BOTH H850-700MB AND H700-500MB SUGGESTING
DEEP MOISTURE POOLING AND THE FORMATION OF A BARRIER JET ASSOCIATED
WITH 50KT-60KT WINDS BELOW 700MB. BOTH THE NAM AND RAP13 INDICATE
0.75 INCHES OF QPF DEVELOPING AS THIS BAND SETS UP THIS MORNING
ACROSS SCNTL NEB. THUS IN CONJUNCTION WITH THE ECM...IT WOULD APPEAR
THE HEAVY SNOW ACROSS WY WILL TRANSLATE EAST THRU WRN AND SCNTL NEB
TODAY. A WINTER WINTER WEATHER ADVISORY REPLACES THE WIND ADVISORY
IN ALL AREAS EXCEPT CUSTER AND FRONTIER COUNTY WHERE TEMPERATURES
ARE EXPECTED TO BE IN THE MID AND UPPER 30S TODAY. THE SUPER
ENSEMBLE TEMPERATURE FORECAST CLUSTERS NORTH PLATTE IN THE LOW TO
MID 30S LATE THIS MORNING AND THIS AFTERNOON.
THE ECM...NAM AND RAP13 WERE USED FOR THE QPF FORECAST WITH A 7 TO 1
SNOW RATIO FOR AROUND 3 INCHES OF SNOW CENTERED OVER LINCOLN COUNTY
NORTH AND SOUTH ALONG HIGHWAY 83. THE MODELS WILL LIKELY MOVE THIS
CENTER AROUND TODAY PERHAPS FARTHER WEST OR EAST OR EVEN SOUTH
DEPENDING ON HOW THE DYNAMICS COME TOGETHER. AT 08Z THE SFC LOW WAS
CENTERED OVER THE OKLAHOMA PANHANDLE AT 990 MB AND IS FORECAST TO
LIFT SLOWLY NORTHEAST TODAY AT AROUND 14KT. THIS SUPPORTS WIND
ADVISORY CONDITIONS WITH GUSTS TO 50 TO 55 MPH. GIVEN THE COMPACT
NATURE OF THE STORM AND THE RELATIVELY FAST MOTION...A PERIOD OF
HARSH WINTER WEATHER SHOULD DEVELOP LASTING 4 TO 8 HOURS. THE HRRR
INDICATES VISIBILITY FALLING TO 1/2 MILE. THE RAP AND NAM INDICATE
PCPN RATES NEAR OR ABOVE 0.10 INCH PER HOUR WHICH IS MODERATE TO
PERHAPS HEAVY SNOW.
THE SNOW SHOULD EXIT THE FORECAST AREA EARLY THIS EVENING THE SFC
LOW SHOULD OVER NRN IL BY WEDNESDAY MORNING. WINDS THIS EVENING
SHOULD DIMINISH AS SKIES CLEAR AND DECOUPLING OCCURS. LOWS TONIGHT
FALL INTO THE 20S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 354 AM CDT TUE MAR 18 2014
GENERAL NORTHWEST FLOW ALOFT CONTINUES UNCHANGED THROUGH THE PERIOD.
SEVERAL UPPER LEVEL DISTURBANCES WILL BE EMBEDDED WITHIN THE FLOW.
DUE TO CONTINUED LIMITED MOISTURE AND THE WEAK NATURE OF THE
SYSTEMS...I AM HESITANT TO INTRODUCE MUCH IN THE WAY OF POPS INTO
THE FORECAST. APPEARS SATURDAY WILL BE THE BEST SHOT FOR US TO
RECEIVE SOME LIGHT PRECIP...AND HAVE INTRODUCED A SLIGHT CHANCE FOR
RAIN OR SNOW SHOWERS.
TEMPERATURE WISE...THE WARMEST DAY WILL BE THURSDAY...AS A THERMAL
RIDGE QUICKLY BUILDS ACROSS THE AREA AHEAD OF A COLD FRONT SET TO
ARRIVE FRIDAY. HIGH PRESSURE...ORIGINATING FROM THE ARCTIC...WILL
BUILD SOUTH INTO THE NORTHERN PLAINS BEHIND THE FRONT DURING THE
WEEKEND...KEEPING TEMPERATURES BELOW NORMAL. A REINFORCING ARCTIC
HIGH PRESSURE CENTER BUILDS SOUTH INTO THE PLAINS EARLY NEXT
WEEK...WITH CONTINUED BELOW NORMAL TEMPERATURES. IN FACT...THE
LATEST RUN OF THE ECMWF MODEL INDICATES 850MB TEMPERATURES OF -10C
TO -15C BY WEDNESDAY MORNING ACROSS THE AREA. LONG STORY
SHORT...WINTER WILL CONTINUE TO HOLD IT/S GRIP DESPITE THE OFFICIAL
ARRIVAL OF SPRING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1244 PM CDT TUE MAR 18 2014
WIDESPREAD IFR/LIFR THIS AFTERNOON AS A POTENT SPRING WINTER STORM
MOVES ACROSS THE AREA. THE MAIN SNOW BAND HAS PUSHED SOUTH AND EAST
OF THE VTN TERMINAL. THE GUSTY NORTHERLY WIND WILL ACCOMPANY LOW
CIGS THIS AFTERNOON...ALTHOUGH CIGS WILL BE INCREASING AS THE
SYSTEM CONTINUES TO PUSH EAST. BETWEEN 00Z AND 03Z EXPECT CIGS TO
LIFT WITH VFR CONDITIONS.
FURTHER SOUTH...FOR THE KLBF TERMINAL...SNOW AND LOW CIGS TO BRING
IFR TO LIFR CONDITIONS FOR THE AFTERNOON DUE TO STRATUS ALONG WITH
SNOW AND BLOWING SNOW. IMPROVING CONDITIONS LATER THIS AFTERNOON.
BY 00Z THE SNOW WILL BE ENDING WITH CIGS TO INCREASE. VFR
CONDITIONS DEVELOP OVERNIGHT AND CONTINUE INTO TOMORROW.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING
FOR NEZ004>010-022>029-035>038-056>059-069>071-094.
&&
$$
UPDATE...MASEK
SHORT TERM...CDC
LONG TERM...TAYLOR
AVIATION...MASEK
AREA FORECAST DISCUSSION...CORRECTEDD
NWS HASTINGS NE
638 AM CDT TUE MAR 18 2014
.UPDATE...
ISSUED AT 1138 AM CDT TUE MAR 18 2014
WITH THE MORNING ANALYSIS...THE NAM WAS ABOUT 3MB TOO WEAK ON THE
SURFACE LOW OVER KANSAS. THE RAP SEEMED TO BE DOING A BETTER JOB.
THIS AFTERNOON...THE SURFACE LOW WILL TRACK TO NORTHEAST KANSAS
WITH THE UPPER TROF SWINGING EAST. THE SURFACE WINDS HAVE TURNED
TO THE NORTHWEST WEST OF HEBRON AND YORK AND HAVE INCREASED TO 25
TO 30 MPH SUSTAINED AROUND KEARNEY AND LEXINGTON. TEMPERATURES AT
11AM CDT WERE IN THE MID 30S IN THE WEST TO NEAR 50 IN THE
EAST...WITH FALLING TEMPERATURES BEHIND THE FRONT. A MIX OF
PRECIPITATION IS EXPECTED...WITH RAIN/RAIN AND SNOW AND SNOW THIS
AFTERNOON DUE TO THE TEMPERATURES. SOME LIGHT SNOW ACCUMULATIONS
ARE FORECAST...ESPECIALLY TOWARD DAWSON/GOSPER/VALLEY/SHERMAN
COUTNIES.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 350 AM CDT TUE MAR 18 2014
FOCUS CONTINUES TO BE ON STORM SYSTEM IMPACTING THE AREA TODAY
THROUGH WEDNESDAY.
SURFACE MAP EARLY THIS MORNING HAD A DEEPENING AREA OF LOW PRESSURE
OVER THE CENTRAL PLAINS WITH A WARM FRONT EXTENDING ACROSS NORTHERN
IA. WARM AIR ADVECTION/ISENTROPIC LIFT PRODUCING QUITE A BIT OF MID-
LEVEL CLOUD ADVECTING NORTHEAST TOWARD THE REGION PER IR SATELLITE.
OTHERWISE... TEMPERATURES EARLY THIS MORNING WERE IN THE MIDDLE 20S
TO THE LOWER 30S.
FOR TODAY THROUGH TONIGHT...MODELS ARE IN DECENT AGREEMENT TAKING
THE LOW FROM THE CENTRAL PLAINS INTO SOUTHERN WI BY 12Z WED. LOOKING
AT INCREASING/THICKENING MID-CLOUD TODAY WITH HIGHS PUSHING UP INTO
THE UPPER 30S TO THE MIDDLE 40S. MAIN DEFORMATION RAIN/SNOW AREA ON
THE NORTHWEST SIDE OF THE LOW EXPECTED TO EXTEND FROM THE CENTRAL
PLAINS INTO CENTRAL/NORTHEAST MN. MEANWHILE...GENERAL INCREASE IN
ISENTROPIC LIFT AND MOISTURE TRANSPORT IN THE 850-700MB LAYER WILL
BE ENOUGH TO GENERATE RAIN/SHOWER ACTIVITY FROM WEST TO EAST
ACROSS OUR AREA TODAY.
LOOK FOR THE RAIN TO TRANSITION OVER TO SNOW FROM WEST TO EAST AS
THE LOW PUSHES INTO SOUTHERN WI BY WEDNESDAY MORNING WITH DYNAMIC
COOLING THROUGH THE COLUMN ASSOCIATED WITH THE UPPER
TROUGH/DEFORMATION AREA.
RIGHT NOW...LOOKS LIKE THE TRANSITION FROM RAIN TO SNOW WILL TAKE
PLACE FASTER ACROSS NORTH CENTRAL WI INTO SOUTHEAST MN SOMEWHERE IN
THE 03-05Z TIME FRAME...AND THEN ACROSS THE REST OF THE AREA THROUGH
WEDNESDAY MORNING. EXPECTING 2-3 INCHES ACROSS TAYLOR COUNTY
OVERNIGHT AND 2-2.5 IN THE ROCHESTER/DODGE CENTER/AUSTIN AREA.
APPEARS HEAVIER DEFORMATION PRECIPITATION WILL DISSIPATE/MOVE
NORTHEAST WITH THE LOW AS IT MOVES TOWARD NORTHWEST LOWER MI BY 18Z
WED. SO...LOOKS LIKE AROUND ANOTHER 1-2 INCHES OF SNOW COULD OCCUR
ACROSS NORTH CENTRAL WI //CLARK AND TAYLOR COUNTY// THROUGH
WEDNESDAY MORNING...WITH LESS THAN A HALF INCH EXPECTED ELSEWHERE.
SNOW TOTAL ACROSS TAYLOR COUNTY APPEARS TO BE IN THE 3-5 INCH RANGE
FROM TONIGHT THROUGH WEDNESDAY...SO WILL GO AHEAD HOIST A WINTER
WEATHER ADVISORY FOR THEM VALID 19.03Z THROUGH 19.18Z.
OTHER FACET OF THIS STORM SYSTEM WILL BE GUSTY NORTHWEST WINDS
DURING THE DAY WEDNESDAY. APPEARS WINDS WILL REMAIN BELOW HEADLINE
CRITERIA AT THIS POINT BUT BLUSTERY NONETHELESS IN THE SUSTAINED 15-
25 MPH GUSTING 35 MPH RANGE. SINCE THE SNOW WILL BE ON THE WETTER
SIDE RATHER THAN FLUFFY VARIETY...NOT MUCH IN THE WAY OF BLOWING
SNOW IS ANTICIPATED. LOOK FOR COOLER CONDITIONS OTHERWISE...WITH
HIGHS TOPPING OFF IN THE 34-40 DEGREE RANGE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 350 AM CDT TUE MAR 18 2014
HIGH PRESSURE BUILDS IN WEDNESDAY NIGHT AS THE LOW PULLS INTO
EASTERN ONTARIO. LOOK FOR NORTHWEST WINDS TO DIMINISH RAPIDLY
THROUGH THE EVENING WITH SKIES CLEARING FROM WEST TO EAST. OVERNIGHT
LOWS ARE EXPECTED TO COOL DOWN INTO THE TEENS AND LOWER 20S.
LOOK FOR A DRY DAY THURSDAY...BUT WITH INCREASING HIGH/MID CLOUDS AS
THE DAY WEARS ON AHEAD OF LOW PRESSURE MOVING OUT OF ALBERTA CANADA
INTO THE NORTHERN PLAINS. OTHERWISE...TEMPERATURES WILL BE RIGHT
AROUND NORMAL WITH HIGHS IN THE MIDDLE 30S TO THE MIDDLE 40S.
FOR LATE THURSDAY NIGHT THROUGH FRIDAY NIGHT...MODELS ARE BECOMING
MORE CONSISTENT WITH LOW MOVING ACROSS THE NORTHERN PLAINS AND
ACROSS THE UPPER MISSISSIPPI RIVER VALLEY REGION FOR A CHANCE OF
SNOW...MIXING WITH/CHANGING TO RAIN DURING THE DAY FRIDAY AS
TEMPERATURES CLIMB INTO THE MIDDLE 30S TO MIDDLE 40S. POPS MAY
HAVE TO RAISED SOME CENTERED ON FRIDAY BASED ON INCREASINGLY
CONSISTENT PRECIPITATION SIGNAL.
SATURDAY THROUGH SUNDAY LOOK DRY BUT COLD AS CANADIAN HIGH PRESSURE
SETTLES INTO THE REGION. PLAN ON HIGHS IN THE 20S AND 30S.
PRECIPITATION CHANCES RETURN TO THE AREA SUNDAY NIGHT/MONDAY AS
NORTHWEST FLOW ALOFT BRINGS ANOTHER MID-LEVEL TROUGH AND WEAK
SURFACE LOW INTO THE REGION. LOOKS LIKE A CHANCE OF ALL SNOW SUNDAY
NIGHT WITH THE MAJORITY OF THE PRECIPITATION REMAINING IN THE FORM
OF SNOW INTO MONDAY. COULD SEE A TRANSITION TO RAIN ACROSS NORTHEAST
IOWA. LOOK FOR HIGHS TOPPING OFF IN THE MIDDLE 20S ACROSS NORTH
CENTRAL WI...AND NEAR 40 ACROSS PORTIONS OF NORTHEAST IOWA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 643 AM CDT TUE MAR 18 2014
THE MAIN FOCUS WITH THE TAFS IS WITH WHEN THE PRECIPITATION WILL
START UP ALONG WITH WHEN IT WILL CHANGE FROM RAIN TO SNOW.
CURRENTLY...VFR CONDITIONS ARE THE RULE ACROSS THE LOCAL TAF SITES
AS A LOW PRESSURE SYSTEM BECOMES ORGANIZED IN THE SOUTH CENTRAL
PLAINS. A FEW RAIN SHOWERS MAY DEVELOP THIS AFTERNOON...BUT THE
MAIN SLUG OF MOISTURE WILL COME IN THIS EVENING AS THE LOW
APPROACHES FROM THE SOUTH. PRECIPITATION WILL START OUT AS RAIN
WITH CEILINGS LIKELY DROPPING TO MVFR AS IT BEGINS THIS EVENING.
CEILINGS MAY DROP TO IFR/LOW END MVFR BEFORE THE CHANGE OVER TO
SNOW...BUT CONFIDENCE IN THAT OCCURRING WAS NOT HIGH ENOUGH AT
THIS POINT. MOST OF THE MODEL GUIDANCE IS SUGGESTING THAT THE
CHANGE OVER TO SNOW WILL OCCUR AFTER 2AM OR SO...THOUGH THERE IS A
MODEL OR TWO SAYING THAT CONDITIONS MAY BE COLD ENOUGH FOR SNOW TO
OCCUR EARLIER THAN THAT. WILL HAVE TO MONITOR TRENDS THROUGH THE
DAY...BUT EXPECT THAT VISIBILITY WILL DROP TO IFR AS THE SNOW
DEVELOPS OVERNIGHT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...WIND ADVISORY FROM NOON TODAY TO 10 PM CDT THIS EVENING FOR
NEZ040-041-047>049-062>064-075>077-085>087.
WIND ADVISORY UNTIL 10 PM CDT THIS EVENING FOR NEZ039-046-060-
061-072>074-082>084.
WINTER WEATHER ADVISORY FROM 11 AM TO 7PM CDT THIS EVENING FOR
NEZ060-039-046-072.
KS...WIND ADVISORY FROM NOON TODAY TO 10 PM CDT THIS EVENING FOR
KSZ007-019.
WIND ADVISORY UNTIL 10 PM CDT THIS EVENING FOR KSZ005-006-017-
018.
&&
$$
UPDATE...ZAPOTOCNY
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
619 PM EDT TUE MAR 18 2014
.SYNOPSIS...
A WARMING AND DRYING TREND IS EXPECTED THROUGH SATURDAY AS A LATE
WINTER STORM SYSTEM PULLS NORTHEAST AWAY FROM THE AREA AND HIGH
PRESSURE SETTLES INTO THE REGION. A COLD FRONT IS EXPECTED TO
CROSS THE COAST LATE IN THE WEEKEND...FOLLOWED BY BELOW NORMAL
TEMPERATURES EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 6 PM TUESDAY...FINAL PATCHES OF LIGHT DRIZZLE ARE FADING AS
THE MOVE SW ACROSS OUR NC COUNTIES. HAVE CAPPED POPS AT SLIGHT
CHANCE OR LOWER FOR THE REMAINDER OF THE OVERNIGHT PERIOD. MOST
PLACES WILL STAY DRY. NO OTHER CHANGES TO THE FORECAST WITH THE
LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS:
THE UPPER LEVEL LOW HAS MOVED WELL OFF SHORE THIS AFTERNOON AND
THE SURFACE LOW IS ABOUT 100 MILES SOUTHEAST OF THE CAPE FEAR.
WHAT THIS HAS DONE IS SCOUR OUT THE DRY AIR ALOFT AND NOW ONLY THE
MOISTURE SEEN ON RAP TIME HEIGHT CROSS SECTION WILL REMAIN
OVERNIGHT MAINLY BELOW 800 MB.
THE SYNOPTIC SETTING AT THE SURFACE SHOWS COLD AIR DAMMING AND
THIS WILL ALLOW NORTH TO NORTHEAST FLOW TO REMAIN OVER THE AREA
OVERNIGHT. WITH NO FORCING ALOFT AND ABUNDANT MOISTURE EXPECT
STRATUS CLOUDS TO REMAIN OVERNIGHT...WITH THE POSSIBILITY OF SOME
LIGHT DRIZZLE AND PATCHY FOG. CURRENT SATELLITE IS SHOWING A BREAK
ALONG THE SOUTHEAST NORTH CAROLINA COAST BUT AS LOW MOVES AWAY AND
SUBSIDENCE ON THE BACK SIDE WEAKENS EXPECT THE CLOUD COVER TO FILL
IN OVERNIGHT.
WITH TEMPERATURES STRUGGLING TO MAKE THE LOW TO MID 40S THIS
AFTERNOON WILL AGAIN LEAN TOWARD A COOLER SOLUTION AS SEEN IN THE
MET MOS GUIDANCE...WHICH MAY BE A BIT TO COLD. TEMPERATURES ARE
EXPECTED TO REMAIN IN THE MID 30S BUT WITH CLOUD COVER AND A NORTH
WIND THE EXPECTATION OF FROST IS NOT HIGH FOR THE OVERNIGHT.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...WESTERLY WIND FLOW IN A PARCHED AIR-MASS
PERCHED ABOVE 8000 FEET WILL COVER THE AREA BOTH WEDNESDAY AND
THURSDAY. PATCHY -RA/-DZ MAY LINGER OVER OUR FAR NE ZONES VERY
EARLY ON WEDNESDAY AROUND 12Z/8AM...AS A STORM SYSTEM CIRCULATION
THROWS MOISTURE OVER-TOP AN ERODING HIGH PRESSURE WEDGE. RESIDUAL
LOW-LEVEL MOISTURE AND WEAK SHORT-WAVE ENERGY FROM THE WNW MAY
ALSO AID IN LIGHT PCPN AROUND THIS TIME.
A WEAK COLD FRONT WEDNESDAY NIGHT WILL BRING A SECONDARY INCREASE
IN RELATIVE HUMIDITY UP THROUGH 800 MB BUT THIS LOOKS INADEQUATE
TO GENERATE ANY PCPN SO NO MENTIONABLE POP VALUES ARE PLANNED. NO
SIGNIFICANT COLD ADVECTION IS EXPECTED AND IN TERMS OF SENSIBLE
WEATHER...MAINLY LOW-LEVEL CLOUDS LATE WED/EARLY THU EXPECTED.
PLENTIFUL SUNSHINE WILL BE A STRUGGLE EARLY WEDNESDAY DUE TO THE
WEAKENING WEDGE AND LOW-LEVEL MOISTURE ON NE TRAJECTORIES...AND
AGAIN VERY EARLY ON THURSDAY WE MAY BE GREETED WITH CLOUDS. BREAKS
AND PERIODS OF AFTERNOON SUNSHINE HOWEVER SHOULD PERIODICALLY
PREVAIL...THIS MOST FAVORABLE THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...QUIET AND COOL CONDITIONS WILL KICK OFF THE
FORECAST PERIOD AS SFC HIGH PRESSURE OVER THE REGION GRADUALLY
TRANSITIONS OFF THE CAROLINA COAST LATE MORNING/EARLY AFTERNOON ON
FRIDAY. BEHIND THE EXITING SYSTEM SW FLOW WILL RETURN AT THE SFC
WHILE ZONAL WESTERLY FLOW ALOFT RESIDES...MAKING FOR OVERALL DRY
CONDITIONS TO PERSIST INTO SATURDAY MORNING. AN BROAD UPPER LEVEL
TROUGH WELL TO THE NORTH-NORTHWEST WILL AID IN THE FORWARD PUSHING
OF A COLD FRONT...WHICH WILL APPROACH OUR AREA ON SATURDAY.
ANTICIPATE CLOUD COVER TO SLOWLY INCREASE BEGINNING AS EARLY AS LATE
OVERNIGHT FRIDAY INTO EARLY SATURDAY MORNING PER LATEST FCST
SOUNDINGS. AS DRY CONDITIONS PERSIST ALOFT WITH WESTERLY
WINDS...WITH THE FRONTAL PASSAGE...ONLY AVAILABLE MOISTURE WILL BE
THAT INFILTRATED INTO THE AREA BY THE PREVIOUSLY MENTIONED SOUTHWEST
FLOW. THUS DO NOT ANTICIPATE MUCH IN THE WAY OF RAINFALL AMOUNTS
WITH THE SYSTEM.
INTO SUNDAY...CLOUDS WILL DISPERSE AND QUIET CONDITIONS RETURN AS
HIGH PRESSURE BUILDS BACK INTO THE AREA. THOUGH WILL NOTE MUCH
COOLER AIR INFILTRATES IN...ALLOWING FOR SLIGHTLY BELOW AVERAGE
TEMPS FOR SUNDAY THROUGH TUESDAY. WILL NEED TO MONITOR NEXT WEATHER
SYSTEM AS UNSETTLED WEATHER IS POSSIBLE MONDAY INTO TUESDAY AS
STALLED SYSTEM OFFSHORE SLOWLY RETROGRADES TOWARDS THE COAST.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...LOW PRESSURE CONTINUING TO TRACK UP THE EASTERN
SEABOARD WITH ABUNDANT WRAP AROUND LOW LEVEL MOISTURE. LOOK FOR IFR
CEILINGS TO BE PREDOMINATE ACROSS THE REGION THROUGH MUCH OF THE
FORECAST PERIOD. THERE MAY BE A BRIEF RISE TO MVFR AT THE NORTHERN
TERMINALS FOR A COUPLE OR HOURS THIS AFTERNOON...BUT THEY SHOULD GO
RIGHT BACK DOWN NEAR SUNSET. LIKEWISE THERE MAY BE BRIEF PERIODS OF
IFR DRIZZLE...MAINLY AT ILM. NORTHERLY FLOW IS FORECAST THROUGH THE
OVERNIGHT HOURS. WEDNESDAY...SLOWLY IMPROVING CONDITIONS WITH MVFR
EXPECTED AT MOST TERMINALS BY LATE MORNING...POSSIBLY SCATTERING BY
THE END OF THE FORECAST PERIOD.
EXTENDED OUTLOOK...BECOMING VFR WEDNESDAY AFTERNOON. EXPECT VFR
THURSDAY AND FRIDAY. LOW CONFIDENCE FOR POSSIBLE SHOWERS WITH A COLD
FRONT SATURDAY NIGHT INTO SUNDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 6 PM TUESDAY...SMALL CRAFT ADVISORY REMAINS IN PLACE WITH
LATEST OBS SHOWING GUSTY WINDS TO 25 KTS AND 4 TO 6 FT SEAS. NO
CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS
DISCUSSION FOLLOWS:
THE SURFACE LOW PRESSURE AREA ALONG THE STATIONARY FRONT IS NOW
LOCATED AROUND 100 MILES SOUTHEAST OF CAPE FEAR. WITH THE
TIGHTENED PRESSURE GRADIENT...THE WINDS OVER THE WATERS ARE
BECOMING MORE NORTHERLY AND ARE BLOWING AT 20 TO 25 KNOTS WITH
GUSTS NEAR 30 KNOTS. SEAS ARE RUNNING AT 7.5 FEET AT FRYING PAN
SHOALS AND 4.5 FEET AT BUOY 41110 OFF WRIGHTSVILLE BEACH. WINDS
ARE EXPECTED TO REMAIN FROM THE NORTH WITH THE LOW EXITING OFF TO
THE NORTHEAST AND COLD AIR DAMMING OVER THE CAROLINAS CONTINUING
OVERNIGHT. AS THE PRESSURE GRADIENT DECREASES OVERNIGHT...THE
WINDS AND SEAS WILL DECREASE. SO AT THE TIME WILL CONTINUE WITH A
SMALL CRAFT ADVISORY FOR ALL THE WATERS THROUGH MIDNIGHT AND NORTH
OF LITTLE RIVER INLET THROUGH 6 AM.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...OVERALL AN IMPROVED MARINE FORECAST AS WINDS
FALL OFF IN WAKE OF A DEPARTING STORM SYSTEM OFFSHORE. N WINDS
EARLY WEDNESDAY WILL EASE AND BECOME WSW LATER IN THE DAY AS LOWER
PRESSURE TO THE NE PULLS AWAY...AND ALLOWS THE LOW-LEVEL PRESSURE
GRADIENT TO LOOSEN CONSIDERABLY. WINDS WILL GO NW-N THURSDAY AFTN
AS A SURFACE HIGH MOVES IN FROM THE WEST. MODERATE NE WIND SHOULD
BE EXPECTED DAYBREAK FRIDAY PRIOR TO THE HIGH MOVING OVERHEAD OF
THE COASTAL WATERS MIDDAY FRIDAY. SEAS SPECTRUM WILL FEATURE NE
WAVE ENERGY ON THE WANE WEDNESDAY...FOLLOWED BY SMALLER BUT A
MYRIAD OF S-SE MINOR WAVE TRAINS OF DIFFERING WAVE PERIODS.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 3 PM TUESDAY...LIGHT WINDS WILL PREVAIL ON FRIDAY AS HIGH
PRESSURE REIGNS ACROSS THE WATERS AS SEAS REMAIN FAIRLY QUIET
THROUGHOUT THE DAY. INTO THE LATER AFTERNOON HOURS SEAS WILL BUILD TO
2-4 FT...WITH SOME POSSIBLE 5FOOTERS IN THE OUTER WATERS OF AMZ-252
AND 250...AS SOUTH WINDS INCREASE TO 10-12 KTS AND DECENT SWELL
ENERGY IS TAPPED INTO ACROSS THE WATERS. EXPECT CONDITIONS TO LAST
THROUGH SATURDAY AFTER AS A COLD FRONT PUSHES TOWARDS THE COAST FROM
THE NORTHWEST. CONDITIONS QUIET BACK DOWN BEHIND THE COLD FRONT AS
HIGH PRESSURE SETTLES IN WITH SEAS ON SUNDAY MAINLY 2-3 FT AND
MAINLY NORTH WINDS 10-14 KTS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR AMZ254-256.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR AMZ250-252.
&&
$$
SYNOPSIS...MJC
NEAR TERM...DRH/REK
SHORT TERM...MJC
LONG TERM...SGL
AVIATION...DL/DRH
MARINE...MJC/SGL/DRH/REK
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
531 PM EDT TUE MAR 18 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE NORTHEAST OFF THE COAST TONIGHT.
HIGH PRESSURE WILL BUILD IN FROM THE SOUTHWEST WEDNESDAY. A COLD
FRONT WILL PUSH THROUGH THE REGION THURSDAY MORNING. HIGH PRESSURE
BUILDS IN THURSDAY AND FRIDAY BEFORE ANOTHER COLD FRONT PUSHES
THROUGH THE AREA LATE SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 515 PM TUE...QUICK UPDATE TO ISSUE A COASTAL FLOOD ADV FOR
OBX DARE AND HYDE COUNTY AS HAVE GOTTEN SEVERAL REPORTS OF
SOUNDSIDE FLOODING ON HATTERAS ISLAND. WINDS CURRENTLY GUSTING
40-45 KT FROM THE N MOST OF THE WATERS. LATEST HRRR INDICATES
THESE STRONG WINDS DIMINISHING AROUND MID EVENING AND RUC 3 HRLY
PRES RISES DIMINISH QUITE RAPIDLY AS LOW OFFSHORE MIGRATES
EASTWARD. HAVE GALES AND COASTAL FLOOD ADVISORY ENDING AT 11 PM.
PREVIOUS DISCUSSION...AS OF 245 PM TUE...LATEST SFC ANALYSIS
SHOWS 1002MB LOW PRESSURE CENTERED OFF THE NC/SC COAST THIS
AFTERNOON...WHILE SHORTWAVE PUSHES OFF THE SE COAST AIDING IN SFC
CYCLOGENESIS. LIGHT TO MODERATE RAIN ONGOING THIS AFTERNOON...WITH
HEAVIEST ACTIVITY ALONG THE COAST. EXPECT RAIN TO TAPER OFF LATE
THIS AFTERNOON/EVENING AS LOW MOVES FURTHER OFFSHORE...AND
TRANSITION MORE TO LIGHT RAIN/AREAS OF DRIZZLE WITH STRONG LOW
LEVEL INVERSION OVERNIGHT. GUSTY N/NE WINDS WILL CONTINUE ALONG
THE COAST INTO THIS EVENING...WITH GUSTS 30-40MPH FOR THE OUTER
BANKS. OVERNIGHT LOWS IN THE UPPER 30S/MID 40S.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
AS OF 245 PM TUE...TEMPERATURES STILL LOOK TRICKY FOR WED...AS
INSITU DAMMING/WEDGE CONTINUES THROUGH MUCH OF THE DAY BEFORE
SOUTHERLY FLOW RETURNS HELPING TO SCOUR OUT LOW CLOUDS. WILL
CONTINUE TO FORECAST HIGHS IN THE MID 50S/LOWER 60S. STILL EXPECT
PATCHY DRIZZLE/LIGHT RAIN ACROSS THE AREA EARLY WED
MORNING...BECOMING MORE ISOLATED IN THE AFTERNOON.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
AS OF 300 PM TUESDAY...MODELS IN GENERAL AGREEMENT THAT BUILDING
HEIGHTS AND RETURN TO ZONAL FLOW WILL LEAD TO WARMING AND RELATIVELY
DRY PERIOD FOR THU-SAT...THEN UPPER TROFFING WILL LEAD TO ANOTHER
COLDER AND POSSIBLY WET PERIOD EARLY NEXT WEEK.
SHRT WV WILL PUSH A COLD FRONT THROUGH AREA WED NIGHT INTO EARLY
THU. SUPPORT FOR PRECIP IS WEAK AND CONTINUED WITH JUST 20% POPS FOR
NOW. MAIN EFFECT FROM COLD FRONTAL PASSAGE WILL BE TO SCOUR OUT
WEDGE AIR MASS...REPLACED BY MARITIME HIGH PRES FROM W FOR THU AND
FRIDAY WITH TEMPS BACK TO NEAR NORMAL.
NEXT SIGNIFICANT SHFT WV WILL PUSH IN ANOTHER ARCTIC FRONT LATE SAT
THROUGH SUNDAY. MSTR WILL BE LIMITED WITH GULF INFLOW CUT OFF ALOFT
AND HAVE KEPT POPS AT JUST 20%.
ARCTIC HIGH PRES WILL BUILD IN BEHIND THE FRONT FOR SUN NIGHT AND
MONDAY WITH MUCH BELOW NORMAL TEMPS. 12Z GFS AND ECMWF BOTH INDICATE
SFC LOW DEVELOPMENT ALONG STALLED BNDRY TO S OF AREA NEXT WEEK BUT
DIFFER ON TIMING WITH GFS ABOUT 12-24 HOURS FASTER. THIS WOULD
RESULT IN WINTER WX THREAT WITH COLD AIR MASS IN PLACE OVER ERN
NC...WHILE ECMWF IS SLOWER AND WARMER. LOW CONDIFIDENCE FCST AT THIS
TIME AND HAVE LEANED TO HPC MODEL BLEND AT THIS TIME AND JUST
INDICATING 30% POPS FOR RAIN ON TUE.
LEANED TO PREVIOUS FCST AND EURO MOS FOR MAX TEMPS THU AND FRI WITH
UPR 60S INLAND AROUND 60 OUTER BANKS. SAT LOOKS LIKE WARMEST DAY
WITH PRE-FRONTAL SW FLOW AND HIGHS IN LOWER 70S INLAND. MUCH COLDER
FOR REST OF PERIOD WITH HIGHS AROUND 60 SUNDAY...AND ONLY AROUND 50
MON AND TUE.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
SHORT TERM /THROUGH WEDNESDAY/...
AS OF 1240 PM...IFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD
WITH A FEW BRIEF MOMENTS OF LOW MVFR THIS AFTERNOON. MOS
GUIDANCE/FORECAST SOUNDING HAVE A GOOD AGREEMENT WITH CONDITIONS
REMAINING IFR WITHIN THE SHORT TERM. LOW LEVELS WILL REMAIN MOIST
AND STRONG INVERSION...CEILING CONDITIONS CAN LOWER TO LIFR FOR
DURING THE OVERNIGHT HOURS ALONG WITH VISIBILITY. CONDITIONS WILL
SLOWLY IMPROVE...BUT WILL REMAIN IFR FOR THE MORNING HOURS.
CONFIDENCE IS LOW WITH THE TIMING OF MVFR AS THE STRONG INVERSION
WILL REMAIN THROUGH TOMORROW MOST OF THE MORNING.
LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 300 PM TUESDAY...SUB VFR CONDITIONS MAY CONTINUE WED EVENING
BUT EXPECTED TO LIFT AS COLD FRONT MOVERS THROUGH OVERNIGHT. VFR
CONDITIONS WILL BE EXPECTED THU-SAT WITH DRY HIGH PRESSURE OVER THE
AREA. A COLD FRONT APPROACHING SATURDAY WILL BRING A THREAT OF
SHOWERS AND SUB VFR CONDITIONS AGAIN SAT NIGHT AND SUNDAY.
&&
.MARINE...
SHORT TERM /THROUGH WEDNESDAY/...
AS OF 515 PM TUE...UPGRADED ALL WATERS TO GALES AS CURRENT OBS
GUSTING 35-45 KT ALL WATERS. 3 HRLY PRES RISES MAXIMIZED THROUGH
EARLY EVENING WHEREAFTER WINDS SHOULD DIMINISH QUITE RAPIDLY AS
LOW PULLS AWAY AND FURTHER OFFSHORE THIS EVENING.
AS OF 245 PM TUE...GUSTY N/NE WINDS AND ELEVATED SEAS CONTINUE
THROUGH THE PERIOD. GALE WARNINGS IN EFFECT FOR WATERS NORTH OF
OCRACOKE AND STRONG SCA CONDITIONS ELSEWHERE. CURRENT OBS SHOW N
WINDS 20-30KT WITH SOME GUSTS TO 35KT...AND SEAS 10-15FT NORTH AND
7-10FT SOUTH. LOW PRESSURE CENTERED OFF THE NC/SC COAST WILL
CONTINUE TO LIFT NORTHWARD THIS EVENING...WITH WINDS PEAKING LATE
THIS AFTERNOON AND EVENING...THEN GRADUALLY DIMINISHING LATE
TONIGHT. N/NE WINDS 10-15KT EARLY WED...VEERING AND BECOMING SE
IN THE AFTERNOON GENERALLY LESS THAN 15KT. ELEVATED SEAS WILL
CONTINUE INTO WED.
LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 300 PM TUESDAY...SMALL CRAFT ADVISORY CONDITIONS...MAINLY FOR
SEAS AT OR ABOVE 6 FT...ARE EXPECTED OVER THE NORTH CAROLINA COASTAL
WATERS THROUGH MUCH OF THURSDAY SOUTHERN WATERS, AND THURSDAY NIGHT
FOR THE CENTRAL AND NORTHERN WATERS. WINDS WILL BE GENERALLY 10 TO
15 KT THROUGH FRIDAY. AS A COLD FRONT APPROACHES THE WATERS SATURDAY
SOUTHWEST WINDS WILL INCREASE TO 20 TO 25 KT IN THE
AFTERNOON...SHIFTING TO NRLY 15-20 KT WITH FRONTAL PASSAGE SAT NIGHT
AND SUNDAY. SEAS WILL BE BELOW 6 FT BRIEFLY FRI INTO EARLY
SAT...THEN BUILD AGAIN TO 5-7 FT FOR OUTER PORTIONS SAT NIGHT AND
SUNDAY.
&&
.TIDES/COASTAL FLOODING...
AS OF 515 PM TUE...ISSUED SHORT DURATION COASTAL FLOOD ADVISORY
FOR SOUND SIDE DARE/HYDE COUNTIES ON THE OBX AS SEVERAL REPORTS OF
FLOODING ON HATTERAS ISLAND. WINDS CURRENTLY GUSTING ABOVE 40 KT
WILL REMAIN THROUGH MID EVENING BEFORE WINDS DIMINISH RAPIDLY
LATER THIS EVENING. WILL MAINTAIN HIGH SURF ADVISORY FOR NORTHERN
OUTER BANKS AS LONG DURATION OF STRONG N/NE WINDS EXPECTED THROUGH
TONIGHT. BREAKING WAVES OF 8 TO 12 FEET EXPECTED WITH WAVE RUNUP
AND MINOR BEACH EROSION POSSIBLE. THERE COULD EVEN BE SOME MINOR
OCEAN OVERWASH IN MORE VULNERABLE AREAS ALONG HWY 12 DURING THE
TIMES OF HIGH TIDE...ALTHOUGH A CALL TO DARE CO 911 THIS AFTERNOON
INDICATED NO ISSUES AS OF YET ALONG THE NRN OBX OCEANFRONT. MINOR
WATER RISES OF A FOOT OR TWO WILL CONTINUE TO BE POSSIBLE ACROSS
THE SOUTHERN PORTION OF THE PAMLICO SOUND AS WELL.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...COASTAL FLOOD ADVISORY UNTIL 11 PM EDT THIS EVENING FOR NCZ103-
104.
HIGH SURF ADVISORY UNTIL 3 AM EDT WEDNESDAY FOR NCZ103.
MARINE...GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR AMZ130-135-150-
152-154-156-158.
&&
$$
SYNOPSIS...CQD/DAG
NEAR TERM...CQD/TL
SHORT TERM...CQD
LONG TERM...JME
AVIATION...JME/BM
MARINE...JME/CQD/TL
TIDES/COASTAL FLOODING...SK/CQD/TL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
308 PM EDT TUE MAR 18 2014
.SYNOPSIS...
A WARMING AND DRYING TREND IS EXPECTED THROUGH SATURDAY...AS A
LATE WINTER STORM SYSTEM PULLS NORTHEAST AWAY FROM THE AREA AND
HIGH PRESSURE SETTLES INTO THE REGION. A COLD FRONT IS EXPECTED
TO CROSS THE COAST LATE IN THE WEEKEND...FOLLOWED BY BELOW NORMAL
TEMPERATURES EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM TUESDAY...THE UPPER LEVEL LOW HAS MOVED WELL OFF SHORE
THIS AFTERNOON AND THE SURFACE LOW IS ABOUT 100 MILES SOUTHEAST OF
THE CAPE FEAR. WHAT THIS HAS DONE IS SCOUR OUT THE DRY AIR ALOFT AND
NOW ONLY THE MOISTURE SEEN ON RAP TIME HEIGHT CROSS SECTION WILL
REMAIN OVERNIGHT MAINLY BELOW 800 MB.
THE SYNOPTIC SETTING AT THE SURFACE SHOWS COLD AIR DAMMING AND
THIS WILL ALLOW NORTH TO NORTHEAST FLOW TO REMAIN OVER THE AREA
OVERNIGHT. WITH NO FORCING ALOFT AND ABUNDANT MOISTURE EXPECT
STRATUS CLOUDS TO REMAIN OVERNIGHT...WITH THE POSSIBILITY OF SOME
LIGHT DRIZZLE AND PATCHY FOG. CURRENT SATELLITE IS SHOWING A BREAK
ALONG THE SOUTHEAST NORTH CAROLINA COAST BUT AS LOW MOVES AWAY AND
SUBSIDENCE ON THE BACK SIDE WEAKENS EXPECT THE CLOUD COVER TO FILL
IN OVERNIGHT.
WITH TEMPERATURES STRUGGLING TO MAKE THE LOW TO MID 40S THIS
AFTERNOON WILL AGAIN LEAN TOWARD A COOLER SOLUTION AS SEEN IN THE
MET MOS GUIDANCE...WHICH MAY BE A BIT TO COLD. TEMPERATURES ARE
EXPECTED TO REMAIN IN THE MID 30S BUT WITH CLOUD COVER AND A NORTH
WIND THE EXPECTATION OF FROST IS NOT HIGH FOR THE OVERNIGHT.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...WESTERLY WIND FLOW IN A PARCHED AIR-MASS
PERCHED ABOVE 8000 FEET WILL COVER THE AREA BOTH WEDNESDAY AND
THURSDAY. PATCHY -RA/-DZ MAY LINGER OVER OUR FAR NE ZONES VERY
EARLY ON WEDNESDAY AROUND 12Z/8AM...AS A STORM SYSTEM CIRCULATION
THROWS MOISTURE OVER-TOP AN ERODING HIGH PRESSURE WEDGE. RESIDUAL
LOW-LEVEL MOISTURE AND WEAK SHORT-WAVE ENERGY FROM THE WNW MAY
ALSO AID IN LIGHT PCPN AROUND THIS TIME.
A WEAK COLD FRONT WEDNESDAY NIGHT WILL BRING A SECONDARY INCREASE
IN RELATIVE HUMIDITY UP THROUGH 800 MB BUT THIS LOOKS INADEQUATE
TO GENERATE ANY PCPN SO NO MENTIONABLE POP VALUES ARE PLANNED. NO
SIGNIFICANT COLD ADVECTION IS EXPECTED AND IN TERMS OF SENSIBLE
WEATHER...MAINLY LOW-LEVEL CLOUDS LATE WED/EARLY THU EXPECTED.
PLENTIFUL SUNSHINE WILL BE A STRUGGLE EARLY WEDNESDAY DUE TO THE
WEAKENING WEDGE AND LOW-LEVEL MOISTURE ON NE TRAJECTORIES...AND
AGAIN VERY EARLY ON THURSDAY WE MAY BE GREETED WITH CLOUDS. BREAKS
AND PERIODS OF AFTERNOON SUNSHINE HOWEVER SHOULD PERIODICALLY
PREVAIL...THIS MOST FAVORABLE THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...QUIET AND COOL CONDITIONS WILL KICK OFF THE
FORECAST PERIOD AS SFC HIGH PRESSURE OVER THE REGION GRADUALLY
TRANSITIONS OFF THE CAROLINA COAST LATE MORNING/EARLY AFTERNOON ON
FRIDAY. BEHIND THE EXITING SYSTEM SW FLOW WILL RETURN AT THE SFC
WHILE ZONAL WESTERLY FLOW ALOFT RESIDES...MAKING FOR OVERALL DRY
CONDITIONS TO PERSIST INTO SATURDAY MORNING. AN BROAD UPPER LEVEL
TROUGH WELL TO THE NORTH-NORTHWEST WILL AID IN THE FORWARD PUSHING
OF A COLD FRONT...WHICH WILL APPROACH OUR AREA ON SATURDAY.
ANTICIPATE CLOUD COVER TO SLOWLY INCREASE BEGINNING AS EARLY AS LATE
OVERNIGHT FRIDAY INTO EARLY SATURDAY MORNING PER LATEST FCST
SOUNDINGS. AS DRY CONDITIONS PERSIST ALOFT WITH WESTERLY
WINDS...WITH THE FRONTAL PASSAGE...ONLY AVAILABLE MOISTURE WILL BE
THAT INFILTRATED INTO THE AREA BY THE PREVIOUSLY MENTIONED SOUTHWEST
FLOW. THUS DO NOT ANTICIPATE MUCH IN THE WAY OF RAINFALL AMOUNTS
WITH THE SYSTEM.
INTO SUNDAY...CLOUDS WILL DISPERSE AND QUIET CONDITIONS RETURN AS
HIGH PRESSURE BUILDS BACK INTO THE AREA. THOUGH WILL NOTE MUCH
COOLER AIR INFILTRATES IN...ALLOWING FOR SLIGHTLY BELOW AVERAGE
TEMPS FOR SUNDAY THROUGH TUESDAY. WILL NEED TO MONITOR NEXT WEATHER
SYSTEM AS UNSETTLED WEATHER IS POSSIBLE MONDAY INTO TUESDAY AS
STALLED SYSTEM OFFSHORE SLOWLY RETROGRADES TOWARDS THE COAST.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...LOW PRESSURE CONTINUING TO TRACK UP THE EASTERN
SEABOARD WITH ABUNDANT WRAP AROUND LOW LEVEL MOISTURE. LOOK FOR IFR
CEILINGS TO BE PREDOMINATE ACROSS THE REGION THROUGH MUCH OF THE
FORECAST PERIOD. THERE MAY BE A BRIEF RISE TO MVFR AT THE NORTHERN
TERMINALS FOR A COUPLE OR HOURS THIS AFTERNOON...BUT THEY SHOULD GO
RIGHT BACK DOWN NEAR SUNSET. LIKEWISE THERE MAY BE BRIEF PERIODS OF
IFR DRIZZLE...MAINLY AT ILM. NORTHERLY FLOW IS FORECAST THROUGH THE
OVERNIGHT HOURS. WEDNESDAY...SLOWLY IMPROVING CONDITIONS WITH MVFR
EXPECTED AT MOST TERMINALS BY LATE MORNING...POSSIBLY SCATTERING BY
THE END OF THE FORECAST PERIOD.
EXTENDED OUTLOOK...BECOMING VFR WEDNESDAY AFTERNOON. EXPECT VFR
THURSDAY AND FRIDAY. LOW CONFIDENCE FOR POSSIBLE SHOWERS WITH A COLD
FRONT SATURDAY NIGHT INTO SUNDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM TUESDAY...THE SURFACE LOW PRESSURE AREA ALONG THE STATIONARY
FRONT IS NOW LOCATED AROUND 100 MILES SOUTHEAST OF CAPE FEAR. WITH
THE TIGHTENED PRESSURE GRADIENT...THE WINDS OVER THE WATERS ARE
BECOMING MORE NORTHERLY AND ARE BLOWING AT 20 TO 25 KNOTS WITH GUSTS
NEAR 30 KNOTS. SEAS ARE RUNNING AT 7.5 FEET AT FRYING PAN SHOALS AND
4.5 FEET AT BUOY 41110 OFF WRIGHTSVILLE BEACH. WINDS ARE EXPECTED TO
REMAIN FROM THE NORTH WITH THE LOW EXITING OFF TO THE NORTHEAST AND
COLD AIR DAMMING OVER THE CAROLINAS CONTINUING OVERNIGHT. AS THE
PRESSURE GRADIENT DECREASES OVERNIGHT...THE WINDS AND SEAS WILL
DECREASE. SO AT THE TIME WILL CONTINUE WITH A SMALL CRAFT ADVISORY
FOR ALL THE WATERS THROUGH MIDNIGHT AND NORTH OF LITTLE RIVER INLET
THROUGH 6 AM.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...OVERALL AN IMPROVED MARINE FORECAST AS WINDS
FALL OFF IN WAKE OF A DEPARTING STORM SYSTEM OFFSHORE. N WINDS
EARLY WEDNESDAY WILL EASE AND BECOME WSW LATER IN THE DAY AS LOWER
PRESSURE TO THE NE PULLS AWAY...AND ALLOWS THE LOW-LEVEL PRESSURE
GRADIENT TO LOOSEN CONSIDERABLY. WINDS WILL GO NW-N THURSDAY AFTN
AS A SURFACE HIGH MOVES IN FROM THE WEST. MODERATE NE WIND SHOULD
BE EXPECTED DAYBREAK FRIDAY PRIOR TO THE HIGH MOVING OVERHEAD OF
THE COASTAL WATERS MIDDAY FRIDAY. SEAS SPECTRUM WILL FEATURE NE
WAVE ENERGY ON THE WANE WEDNESDAY...FOLLOWED BY SMALLER BUT A
MYRIAD OF S-SE MINOR WAVE TRAINS OF DIFFERING WAVE PERIODS.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 3 PM TUESDAY...LIGHT WINDS WILL PREVAIL ON FRIDAY AS HIGH
PRESSURE REIGNS ACROSS THE WATERS AS SEAS REMAIN FAIRLY QUIET
THROUGHOUT THE DAY. INTO THE LATER AFTERNOON HOURS SEAS WILL BUILD TO
2-4 FT...WITH SOME POSSIBLE 5FOOTERS IN THE OUTER WATERS OF AMZ-252
AND 250...AS SOUTH WINDS INCREASE TO 10-12 KTS AND DECENT SWELL
ENERGY IS TAPPED INTO ACROSS THE WATERS. EXPECT CONDITIONS TO LAST
THROUGH SATURDAY AFTER AS A COLD FRONT PUSHES TOWARDS THE COAST FROM
THE NORTHWEST. CONDITIONS QUIET BACK DOWN BEHIND THE COLD FRONT AS
HIGH PRESSURE SETTLES IN WITH SEAS ON SUNDAY MAINLY 2-3 FT AND
MAINLY NORTH WINDS 10-14 KTS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR AMZ254-256.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT WEDNESDAY FOR AMZ250-252.
&&
$$
NEAR TERM...DRH
SHORT TERM...MJC
LONG TERM...SGL
AVIATION...DL/DRH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
255 PM CDT TUE MAR 18 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 255 PM CDT TUE MAR 18 2014
MAIN CONCERN IS WITH THE PRECIPITATION CHANCES TONIGHT INTO
WEDNESDAY.
WATER VAPOR SATELLITE THIS AFTERNOON SHOWING AN UPPER LEVEL LOW
OVER NEBRASKA AND KANSAS WITH NORTHERN STREAM SHORT WAVE TROUGHS
OVER NORTH DAKOTA AND MONTANA. THE 18.12Z MODELS ARE IN REASONABLY
GOOD AGREEMENT IN TAKING THE UPPER LEVEL LOW TOWARD THE EASTERN
GREAT LAKES TONIGHT THROUGH WEDNESDAY MORNING AS THE TWO NORTHERN
STREAM SHORT WAVE TROUGHS MOVE EAST/SOUTHEAST TOWARD THE NORTHERN
GREAT LAKES. THE 18.12Z GFS INDICATES THIS WILL PATTERN WILL TAKE
MODERATE PV ADVECTION IN THE 500-300 MB LAYER ACROSS THE SOUTHERN
SECTIONS OF THE FORECAST AREA TONIGHT AND THEN SWING MODERATE TO
STRONG PV ADVECTION ACROSS THE ENTIRE AREA WEDNESDAY MORNING. THIS
IS EXPECTED TO LEAD TO MODERATE QG CONVERGENCE IN THE 850-500 MB
LAYER THIS EVENING AND SOME LINGERING WEAK CONVERGENCE IN THE
500-300 MB LAYER THROUGH WEDNESDAY. AS THE SURFACE LOW TRACKS FROM
EASTERN KANSAS INTO NORTHERN LOWER MICHIGAN THROUGH WEDNESDAY
MORNING...A BAND OF WEAK FRONTOGENESIS ON THE NORTHWEST SIDE OF
THE LOW IS EXPECTED TO SET UP IN THE 850-500 MB LAYER. THE BEST
ISENTROPIC UP GLIDE WILL OCCUR TONIGHT AHEAD OF THE SURFACE LOW
WITH 2 TO 4 UBAR/S SHOWN BY THE GFS ON THE 285K SURFACE. ALL THIS
FORCING WILL BE MORE THAN SUFFICIENT TO PRODUCE PRECIPITATION
ACROSS THE ENTIRE AREA TONIGHT. CHANGES TO THE PRECIPITATION
CHANCES THAT WERE MADE WERE TO SLOW DOWN THE ARRIVAL OF THE
PRECIPITATION ACROSS THE EAST TO THE LATE EVENING HOURS...CARRYING
A 100 PERCENT CHANCE AFTER 06Z FOR THE ENTIRE AREA AND THEN HAVING
A SHARPER BACK EDGE AS THE PRECIPITATION DEPARTS WEDNESDAY WHICH
ENDS UP KEEPING MOST OF THE AREA WEST OF THE MISSISSIPPI RIVER DRY
FOR WEDNESDAY AFTERNOON.
THE MAIN CONCERN CONTINUES TO BE HOW MUCH WARM AIR WILL WRAP
AROUND THE BACK SIDE OF THE SURFACE LOW. THE 18.12Z NAM SHOWS A
WARMER SOLUTION THAN EITHER THE GFS OR 18.12Z ECMWF WITH THE 0C
LINE FROM NORTH CENTRAL IOWA INTO CENTRAL WISCONSIN WITH ABOUT -2C
OVER THE NORTHWEST SECTIONS. THE GFS HAS THE 0C LINE FARTHER
SOUTHEAST...JUST BARELY INTO THE SOUTHERN SECTIONS WITH ABOUT -3C
AIR OVER THE NORTHWEST. THE ECWMF IS SIMILAR TO THE GFS WITH THE
0C LINE BUT CLOSER TO THE NAM WITH -2C OVER THE NORTHWEST. ALL THE
MODELS THEN SHOW THIS WARM AIR ALOFT SLIDING OUT OF THE AREA
OVERNIGHT ONCE THE SURFACE LOW GOES BY. THE 18.18Z RAP LOOKS VERY
SIMILAR TO THE NAM THROUGH 06Z...SO CONCERNED THAT THE WARMER
SOLUTION MAY END UP BEING CORRECT. FOR NOW...SPLIT THE DIFFERENCE
BETWEEN THE SOLUTIONS...BUT WITH ALL OF THEM SHOWING SOME WARM AIR
ALOFT...THE LEADS TO THE CONCERN FOR SOME SLEET IN THE TRANSITION
BETWEEN THE RAIN TO SNOW AND HAVE ADDED THIS IN AS A POSSIBLE
WEATHER TYPE. WHERE IT WILL BE COLD ENOUGH FOR PREDOMINANTLY
SNOW...ACCUMULATIONS STILL LOOK TO BE 1 TO 2 INCHES ALONG AND
NORTH OF I90 WITH UP TO 3 INCHES IN TAYLOR COUNTY. THUS...NOT
PLANNING ANY CHANGES TO THE CURRENT WINTER WEATHER ADVISORY.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 255 PM CDT TUE MAR 18 2014
THE ACTIVE WEATHER PATTERN LOOKS LIKE IT WILL CONTINUE THROUGH
THIS PERIOD. THE NEXT SYSTEM WILL BE IN THE NORTHERN STREAM COMING
IN FROM SOUTHWEST CANADA. THE CURRENT INDICATIONS FROM THE GFS AND
ECMWF ARE THAT THIS SYSTEM WILL FLATTEN OUT AND MOVE ACROSS THE
NORTHERN PLAINS AND NORTHERN GREAT LAKES. THE INITIAL SURFACE LOW
IS EXPECTED TO BE CLOSE TO THE UPPER LEVEL SYSTEM BUT THEN SHIFT
SOUTH CLOSER TO THE EXISTING BAROCLINIC ZONE. THE MAIN CONCERN
WITH THIS SYSTEM LOOKS TO BE WHETHER SATURATION WILL OCCUR BEFORE
OR AFTER THE SURFACE LOW HAS PASSED BY THE REGION. THE ECMWF IS
THE QUICKEST TO BRING THE PRECIPITATION IN THURSDAY NIGHT AND
FRIDAY WHILE THE NAM AND GFS PRIMARILY KEEP THE AREA DRY ALLOWING
SATURATION TO OCCUR ONCE THE LOW IS PAST THE AREA. WILL SHOW A
SMALL CHANCE ACROSS THE WEST LATE THURSDAY NIGHT WITH A 30 TO 40
PERCENT CHANCE FOR MOST OF THE AREA FRIDAY. THE NEXT NORTHERN
STREAM SYSTEM IS THEN EXPECTED TO MOVE ACROSS THE UPPER MIDWEST
THURSDAY NIGHT AND FRIDAY. THIS SYSTEM COULD BE BATTLING SOME DRY
AIR IN THE LOW LEVELS AS BOTH THE GFS AND ECMWF SHOW HIGH PRESSURE
AT THE SURFACE OVER THE REGION...SO FOR NOW...THIS LEADS TO 30 TO
40 PERCENT CHANCES THURSDAY NIGHT THROUGH FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1150 AM CDT TUE MAR 18 2014
APPROACHING SYSTEM WILL LEAD TO RAIN/SNOW FOR THE TAF LOCATIONS
TONIGHT. INITIALLY WARM AIR IS IN PLACE TO KEEP PRECIP IN LIQUID
FORM. GFS COLDER SOLUTION SUGGESTS A CHANGE TO SNOW MUCH SOONER
BUT NAM/RAP AND OTHER SHORT TERM MESO MODELS SUGGESTING THE WARMER
SOLUTIONS ARE MOST LIKLEY. THUS EXPECT CHANGEOVER TO OCCUR JUST
PAST MIDNIGHT. COULD BE SOME ACCUMULATION...ESPECIALLY AT KRST
AND LOOKS LIKE IT WILL IMPACT THE AIRFIELDS DURING THE MORNING
FLIGHT TIMES. AS THE SYSTEM PASSES...EAST AND NORTHEAST WINDS
AROUND 10 KTS WILL SWITCH TO NORTH AND NORTHWEST AND BECOME RATHER
GUSTY. EXPECTING GUSTS OVER 20 KTS FOR THE MORNING AND AFTERNOON
HOURS OF WEDNESDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 1 PM CDT
WEDNESDAY FOR WIZ017.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...MW